Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
d4e5e70b | 5 | /* Copyright (c) University of Cambridge 1995 - 2017 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* Functions for handling an incoming SMTP call. */ | |
9 | ||
10 | ||
11 | #include "exim.h" | |
2ef7ed08 | 12 | #include <assert.h> |
059ec3d9 PH |
13 | |
14 | ||
15 | /* Initialize for TCP wrappers if so configured. It appears that the macro | |
16 | HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before | |
17 | including that header, and restore its value afterwards. */ | |
18 | ||
19 | #ifdef USE_TCP_WRAPPERS | |
20 | ||
21 | #if HAVE_IPV6 | |
22 | #define EXIM_HAVE_IPV6 | |
23 | #endif | |
24 | #undef HAVE_IPV6 | |
25 | #include <tcpd.h> | |
26 | #undef HAVE_IPV6 | |
27 | #ifdef EXIM_HAVE_IPV6 | |
28 | #define HAVE_IPV6 TRUE | |
29 | #endif | |
30 | ||
31 | int allow_severity = LOG_INFO; | |
32 | int deny_severity = LOG_NOTICE; | |
5dc43717 | 33 | uschar *tcp_wrappers_name; |
059ec3d9 PH |
34 | #endif |
35 | ||
36 | ||
8d67ada3 PH |
37 | /* Size of buffer for reading SMTP commands. We used to use 512, as defined |
38 | by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP | |
39 | commands that accept arguments, and this in particular applies to AUTH, where | |
94431adb | 40 | the data can be quite long. More recently this value was 2048 in Exim; |
e2ca7082 | 41 | however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients |
94431adb HSHR |
42 | such as Thunderbird will send an AUTH with an initial-response for GSSAPI. |
43 | The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and | |
e2ca7082 PP |
44 | we need room to handle large base64-encoded AUTHs for GSSAPI. |
45 | */ | |
46 | ||
bd8fbe36 | 47 | #define SMTP_CMD_BUFFER_SIZE 16384 |
059ec3d9 PH |
48 | |
49 | /* Size of buffer for reading SMTP incoming packets */ | |
50 | ||
bd8fbe36 | 51 | #define IN_BUFFER_SIZE 8192 |
059ec3d9 PH |
52 | |
53 | /* Structure for SMTP command list */ | |
54 | ||
55 | typedef struct { | |
1ba28e2b | 56 | const char *name; |
059ec3d9 PH |
57 | int len; |
58 | short int cmd; | |
59 | short int has_arg; | |
60 | short int is_mail_cmd; | |
61 | } smtp_cmd_list; | |
62 | ||
63 | /* Codes for identifying commands. We order them so that those that come first | |
64 | are those for which synchronization is always required. Checking this can help | |
65 | block some spam. */ | |
66 | ||
67 | enum { | |
68 | /* These commands are required to be synchronized, i.e. to be the last in a | |
69 | block of commands when pipelining. */ | |
70 | ||
71 | HELO_CMD, EHLO_CMD, DATA_CMD, /* These are listed in the pipelining */ | |
72 | VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */ | |
73 | ETRN_CMD, /* This by analogy with TURN from the RFC */ | |
74 | STARTTLS_CMD, /* Required by the STARTTLS RFC */ | |
b3ef41c9 | 75 | TLS_AUTH_CMD, /* auto-command at start of SSL */ |
059ec3d9 PH |
76 | |
77 | /* This is a dummy to identify the non-sync commands when pipelining */ | |
78 | ||
79 | NON_SYNC_CMD_PIPELINING, | |
80 | ||
81 | /* These commands need not be synchronized when pipelining */ | |
82 | ||
83 | MAIL_CMD, RCPT_CMD, RSET_CMD, | |
84 | ||
f4630439 JH |
85 | /* This is a dummy to identify the non-sync commands when not pipelining */ |
86 | ||
87 | NON_SYNC_CMD_NON_PIPELINING, | |
88 | ||
6d5c916c JH |
89 | /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and |
90 | processed the message is sent using a series of BDAT commands" | |
91 | implies that BDAT should be synchronized. However, we see Google, at least, | |
92 | sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for | |
f4630439 JH |
93 | processing of the RCPT response(s). We shall do the same, and not require |
94 | synch for BDAT. Worse, as the chunk may (very likely will) follow the | |
95 | command-header in the same packet we cannot do the usual "is there any | |
4c04137d | 96 | follow-on data after the command line" even for non-pipeline mode. |
f4630439 | 97 | So we'll need an explicit check after reading the expected chunk amount |
4c04137d | 98 | when non-pipe, before sending the ACK. */ |
6d5c916c JH |
99 | |
100 | BDAT_CMD, | |
101 | ||
059ec3d9 PH |
102 | /* I have been unable to find a statement about the use of pipelining |
103 | with AUTH, so to be on the safe side it is here, though I kind of feel | |
104 | it should be up there with the synchronized commands. */ | |
105 | ||
106 | AUTH_CMD, | |
107 | ||
108 | /* I'm not sure about these, but I don't think they matter. */ | |
109 | ||
110 | QUIT_CMD, HELP_CMD, | |
111 | ||
cee5f132 | 112 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
113 | PROXY_FAIL_IGNORE_CMD, |
114 | #endif | |
115 | ||
059ec3d9 PH |
116 | /* These are specials that don't correspond to actual commands */ |
117 | ||
118 | EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD, | |
119 | TOO_MANY_NONMAIL_CMD }; | |
120 | ||
121 | ||
b4ed4da0 PH |
122 | /* This is a convenience macro for adding the identity of an SMTP command |
123 | to the circular buffer that holds a list of the last n received. */ | |
124 | ||
125 | #define HAD(n) \ | |
126 | smtp_connection_had[smtp_ch_index++] = n; \ | |
127 | if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0 | |
128 | ||
059ec3d9 PH |
129 | |
130 | /************************************************* | |
131 | * Local static variables * | |
132 | *************************************************/ | |
133 | ||
134 | static auth_instance *authenticated_by; | |
135 | static BOOL auth_advertised; | |
136 | #ifdef SUPPORT_TLS | |
137 | static BOOL tls_advertised; | |
138 | #endif | |
6c1c3d1d | 139 | static BOOL dsn_advertised; |
059ec3d9 PH |
140 | static BOOL esmtp; |
141 | static BOOL helo_required = FALSE; | |
142 | static BOOL helo_verify = FALSE; | |
143 | static BOOL helo_seen; | |
144 | static BOOL helo_accept_junk; | |
145 | static BOOL count_nonmail; | |
146 | static BOOL pipelining_advertised; | |
2679d413 PH |
147 | static BOOL rcpt_smtp_response_same; |
148 | static BOOL rcpt_in_progress; | |
059ec3d9 | 149 | static int nonmail_command_count; |
8f128379 | 150 | static BOOL smtp_exit_function_called = 0; |
8c5d388a | 151 | #ifdef SUPPORT_I18N |
d1a13eea JH |
152 | static BOOL smtputf8_advertised; |
153 | #endif | |
059ec3d9 PH |
154 | static int synprot_error_count; |
155 | static int unknown_command_count; | |
156 | static int sync_cmd_limit; | |
157 | static int smtp_write_error = 0; | |
158 | ||
2679d413 | 159 | static uschar *rcpt_smtp_response; |
ca86f471 PH |
160 | static uschar *smtp_data_buffer; |
161 | static uschar *smtp_cmd_data; | |
162 | ||
059ec3d9 PH |
163 | /* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their |
164 | final fields of all except AUTH are forced TRUE at the start of a new message | |
165 | setup, to allow one of each between messages that is not counted as a nonmail | |
166 | command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to | |
167 | allow a new EHLO after starting up TLS. | |
168 | ||
169 | AUTH is "falsely" labelled as a mail command initially, so that it doesn't get | |
170 | counted. However, the flag is changed when AUTH is received, so that multiple | |
171 | failing AUTHs will eventually hit the limit. After a successful AUTH, another | |
172 | AUTH is already forbidden. After a TLS session is started, AUTH's flag is again | |
173 | forced TRUE, to allow for the re-authentication that can happen at that point. | |
174 | ||
175 | QUIT is also "falsely" labelled as a mail command so that it doesn't up the | |
2f460950 JH |
176 | count of non-mail commands and possibly provoke an error. |
177 | ||
178 | tls_auth is a pseudo-command, never expected in input. It is activated | |
179 | on TLS startup and looks for a tls authenticator. */ | |
059ec3d9 PH |
180 | |
181 | static smtp_cmd_list cmd_list[] = { | |
d1a13eea JH |
182 | /* name len cmd has_arg is_mail_cmd */ |
183 | ||
059ec3d9 PH |
184 | { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */ |
185 | { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE }, | |
186 | { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE }, | |
187 | { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE }, | |
188 | #ifdef SUPPORT_TLS | |
189 | { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE }, | |
b3ef41c9 | 190 | { "tls_auth", 0, TLS_AUTH_CMD, FALSE, TRUE }, |
059ec3d9 PH |
191 | #endif |
192 | ||
193 | /* If you change anything above here, also fix the definitions below. */ | |
194 | ||
195 | { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE }, | |
196 | { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE }, | |
197 | { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE }, | |
18481de3 | 198 | { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE }, |
059ec3d9 PH |
199 | { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE }, |
200 | { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE }, | |
201 | { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE }, | |
202 | { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE }, | |
203 | { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE }, | |
204 | { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE } | |
205 | }; | |
206 | ||
207 | static smtp_cmd_list *cmd_list_end = | |
208 | cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list); | |
209 | ||
210 | #define CMD_LIST_RSET 0 | |
211 | #define CMD_LIST_HELO 1 | |
212 | #define CMD_LIST_EHLO 2 | |
213 | #define CMD_LIST_AUTH 3 | |
214 | #define CMD_LIST_STARTTLS 4 | |
b3ef41c9 | 215 | #define CMD_LIST_TLS_AUTH 5 |
059ec3d9 | 216 | |
b4ed4da0 PH |
217 | /* This list of names is used for performing the smtp_no_mail logging action. |
218 | It must be kept in step with the SCH_xxx enumerations. */ | |
219 | ||
220 | static uschar *smtp_names[] = | |
221 | { | |
18481de3 JH |
222 | US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN", |
223 | US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET", | |
224 | US"STARTTLS", US"VRFY" }; | |
b4ed4da0 | 225 | |
e524074d | 226 | static uschar *protocols_local[] = { |
981756db PH |
227 | US"local-smtp", /* HELO */ |
228 | US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
229 | US"local-esmtp", /* EHLO */ | |
230 | US"local-esmtps", /* EHLO->STARTTLS->EHLO */ | |
231 | US"local-esmtpa", /* EHLO->AUTH */ | |
232 | US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
059ec3d9 | 233 | }; |
e524074d JH |
234 | static uschar *protocols[] = { |
235 | US"smtp", /* HELO */ | |
236 | US"smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
237 | US"esmtp", /* EHLO */ | |
238 | US"esmtps", /* EHLO->STARTTLS->EHLO */ | |
239 | US"esmtpa", /* EHLO->AUTH */ | |
240 | US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
241 | }; | |
059ec3d9 PH |
242 | |
243 | #define pnormal 0 | |
981756db PH |
244 | #define pextend 2 |
245 | #define pcrpted 1 /* added to pextend or pnormal */ | |
246 | #define pauthed 2 /* added to pextend */ | |
059ec3d9 | 247 | |
d27f98fe TL |
248 | /* Sanity check and validate optional args to MAIL FROM: envelope */ |
249 | enum { | |
2ef7ed08 | 250 | ENV_MAIL_OPT_NULL, |
d27f98fe | 251 | ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH, |
8ccd00b1 | 252 | #ifndef DISABLE_PRDR |
fd98a5c6 | 253 | ENV_MAIL_OPT_PRDR, |
6c1c3d1d | 254 | #endif |
6c1c3d1d | 255 | ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID, |
8c5d388a | 256 | #ifdef SUPPORT_I18N |
d1a13eea JH |
257 | ENV_MAIL_OPT_UTF8, |
258 | #endif | |
d27f98fe TL |
259 | }; |
260 | typedef struct { | |
261 | uschar * name; /* option requested during MAIL cmd */ | |
262 | int value; /* enum type */ | |
263 | BOOL need_value; /* TRUE requires value (name=value pair format) | |
264 | FALSE is a singleton */ | |
265 | } env_mail_type_t; | |
266 | static env_mail_type_t env_mail_type_list[] = { | |
267 | { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE }, | |
268 | { US"BODY", ENV_MAIL_OPT_BODY, TRUE }, | |
269 | { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE }, | |
8ccd00b1 | 270 | #ifndef DISABLE_PRDR |
fd98a5c6 | 271 | { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE }, |
6c1c3d1d | 272 | #endif |
6c1c3d1d WB |
273 | { US"RET", ENV_MAIL_OPT_RET, TRUE }, |
274 | { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE }, | |
8c5d388a | 275 | #ifdef SUPPORT_I18N |
d1a13eea JH |
276 | { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */ |
277 | #endif | |
2ef7ed08 HSHR |
278 | /* keep this the last entry */ |
279 | { US"NULL", ENV_MAIL_OPT_NULL, FALSE }, | |
d27f98fe TL |
280 | }; |
281 | ||
059ec3d9 PH |
282 | /* When reading SMTP from a remote host, we have to use our own versions of the |
283 | C input-reading functions, in order to be able to flush the SMTP output only | |
284 | when about to read more data from the socket. This is the only way to get | |
285 | optimal performance when the client is using pipelining. Flushing for every | |
286 | command causes a separate packet and reply packet each time; saving all the | |
287 | responses up (when pipelining) combines them into one packet and one response. | |
288 | ||
289 | For simplicity, these functions are used for *all* SMTP input, not only when | |
290 | receiving over a socket. However, after setting up a secure socket (SSL), input | |
291 | is read via the OpenSSL library, and another set of functions is used instead | |
292 | (see tls.c). | |
293 | ||
294 | These functions are set in the receive_getc etc. variables and called with the | |
295 | same interface as the C functions. However, since there can only ever be | |
296 | one incoming SMTP call, we just use a single buffer and flags. There is no need | |
297 | to implement a complicated private FILE-like structure.*/ | |
298 | ||
299 | static uschar *smtp_inbuffer; | |
300 | static uschar *smtp_inptr; | |
301 | static uschar *smtp_inend; | |
302 | static int smtp_had_eof; | |
303 | static int smtp_had_error; | |
304 | ||
305 | ||
7e3ce68e | 306 | /* forward declarations */ |
bd8fbe36 | 307 | static int smtp_read_command(BOOL check_sync, unsigned buffer_lim); |
7e3ce68e JH |
308 | static int synprot_error(int type, int code, uschar *data, uschar *errmess); |
309 | static void smtp_quit_handler(uschar **, uschar **); | |
310 | static void smtp_rset_handler(void); | |
311 | ||
f4630439 JH |
312 | /************************************************* |
313 | * Recheck synchronization * | |
314 | *************************************************/ | |
315 | ||
316 | /* Synchronization checks can never be perfect because a packet may be on its | |
925ac8e4 JH |
317 | way but not arrived when the check is done. Normally, the checks happen when |
318 | commands are read: Exim ensures that there is no more input in the input buffer. | |
319 | In normal cases, the response to the command will be fast, and there is no | |
320 | further check. | |
f4630439 JH |
321 | |
322 | However, for some commands an ACL is run, and that can include delays. In those | |
323 | cases, it is useful to do another check on the input just before sending the | |
324 | response. This also applies at the start of a connection. This function does | |
325 | that check by means of the select() function, as long as the facility is not | |
326 | disabled or inappropriate. A failure of select() is ignored. | |
327 | ||
328 | When there is unwanted input, we read it so that it appears in the log of the | |
329 | error. | |
330 | ||
331 | Arguments: none | |
332 | Returns: TRUE if all is well; FALSE if there is input pending | |
333 | */ | |
334 | ||
335 | static BOOL | |
925ac8e4 | 336 | wouldblock_reading(void) |
f4630439 JH |
337 | { |
338 | int fd, rc; | |
339 | fd_set fds; | |
340 | struct timeval tzero; | |
341 | ||
925ac8e4 JH |
342 | if (tls_in.active >= 0 && tls_could_read()) |
343 | return FALSE; | |
f4630439 | 344 | |
40525d07 JH |
345 | if (smtp_inptr < smtp_inend) |
346 | return FALSE; | |
347 | ||
f4630439 JH |
348 | fd = fileno(smtp_in); |
349 | FD_ZERO(&fds); | |
350 | FD_SET(fd, &fds); | |
351 | tzero.tv_sec = 0; | |
352 | tzero.tv_usec = 0; | |
353 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero); | |
354 | ||
355 | if (rc <= 0) return TRUE; /* Not ready to read */ | |
bd8fbe36 | 356 | rc = smtp_getc(GETC_BUFFER_UNLIMITED); |
f4630439 JH |
357 | if (rc < 0) return TRUE; /* End of file or error */ |
358 | ||
359 | smtp_ungetc(rc); | |
360 | rc = smtp_inend - smtp_inptr; | |
361 | if (rc > 150) rc = 150; | |
362 | smtp_inptr[rc] = 0; | |
363 | return FALSE; | |
364 | } | |
365 | ||
925ac8e4 JH |
366 | static BOOL |
367 | check_sync(void) | |
368 | { | |
369 | if (!smtp_enforce_sync || sender_host_address == NULL || sender_host_notsocket) | |
370 | return TRUE; | |
371 | ||
372 | return wouldblock_reading(); | |
373 | } | |
374 | ||
375 | ||
376 | /* If there's input waiting (and we're doing pipelineing) then we can pipeline | |
377 | a reponse with the one following. */ | |
378 | ||
379 | static BOOL | |
380 | pipeline_response(void) | |
381 | { | |
382 | if ( !smtp_enforce_sync || !sender_host_address | |
383 | || sender_host_notsocket || !pipelining_advertised) | |
384 | return FALSE; | |
385 | ||
386 | return !wouldblock_reading(); | |
387 | } | |
388 | ||
f4630439 JH |
389 | |
390 | ||
391 | /************************************************* | |
392 | * Log incomplete transactions * | |
393 | *************************************************/ | |
394 | ||
395 | /* This function is called after a transaction has been aborted by RSET, QUIT, | |
396 | connection drops or other errors. It logs the envelope information received | |
397 | so far in order to preserve address verification attempts. | |
398 | ||
399 | Argument: string to indicate what aborted the transaction | |
400 | Returns: nothing | |
401 | */ | |
402 | ||
403 | static void | |
404 | incomplete_transaction_log(uschar *what) | |
405 | { | |
406 | if (sender_address == NULL || /* No transaction in progress */ | |
407 | !LOGGING(smtp_incomplete_transaction)) | |
408 | return; | |
409 | ||
410 | /* Build list of recipients for logging */ | |
411 | ||
412 | if (recipients_count > 0) | |
413 | { | |
414 | int i; | |
415 | raw_recipients = store_get(recipients_count * sizeof(uschar *)); | |
416 | for (i = 0; i < recipients_count; i++) | |
417 | raw_recipients[i] = recipients_list[i].address; | |
418 | raw_recipients_count = recipients_count; | |
419 | } | |
420 | ||
421 | log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS, | |
422 | "%s incomplete transaction (%s)", host_and_ident(TRUE), what); | |
423 | } | |
424 | ||
425 | ||
426 | ||
427 | ||
0d81dabc JH |
428 | /* Refill the buffer, and notify DKIM verification code. |
429 | Return false for error or EOF. | |
430 | */ | |
431 | ||
432 | static BOOL | |
433 | smtp_refill(unsigned lim) | |
434 | { | |
435 | int rc, save_errno; | |
436 | if (!smtp_out) return FALSE; | |
437 | fflush(smtp_out); | |
438 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
439 | ||
440 | /* Limit amount read, so non-message data is not fed to DKIM */ | |
441 | ||
442 | rc = read(fileno(smtp_in), smtp_inbuffer, MIN(IN_BUFFER_SIZE, lim)); | |
443 | save_errno = errno; | |
444 | alarm(0); | |
445 | if (rc <= 0) | |
446 | { | |
447 | /* Must put the error text in fixed store, because this might be during | |
448 | header reading, where it releases unused store above the header. */ | |
449 | if (rc < 0) | |
450 | { | |
451 | smtp_had_error = save_errno; | |
452 | smtp_read_error = string_copy_malloc( | |
453 | string_sprintf(" (error: %s)", strerror(save_errno))); | |
454 | } | |
455 | else smtp_had_eof = 1; | |
456 | return FALSE; | |
457 | } | |
458 | #ifndef DISABLE_DKIM | |
459 | dkim_exim_verify_feed(smtp_inbuffer, rc); | |
460 | #endif | |
461 | smtp_inend = smtp_inbuffer + rc; | |
462 | smtp_inptr = smtp_inbuffer; | |
463 | return TRUE; | |
464 | } | |
465 | ||
059ec3d9 PH |
466 | /************************************************* |
467 | * SMTP version of getc() * | |
468 | *************************************************/ | |
469 | ||
470 | /* This gets the next byte from the SMTP input buffer. If the buffer is empty, | |
471 | it flushes the output, and refills the buffer, with a timeout. The signal | |
472 | handler is set appropriately by the calling function. This function is not used | |
4c04137d | 473 | after a connection has negotiated itself into an TLS/SSL state. |
059ec3d9 | 474 | |
bd8fbe36 | 475 | Arguments: lim Maximum amount to read/buffer |
059ec3d9 PH |
476 | Returns: the next character or EOF |
477 | */ | |
478 | ||
479 | int | |
bd8fbe36 | 480 | smtp_getc(unsigned lim) |
059ec3d9 PH |
481 | { |
482 | if (smtp_inptr >= smtp_inend) | |
0d81dabc | 483 | if (!smtp_refill(lim)) |
059ec3d9 | 484 | return EOF; |
059ec3d9 PH |
485 | return *smtp_inptr++; |
486 | } | |
487 | ||
0d81dabc JH |
488 | uschar * |
489 | smtp_getbuf(unsigned * len) | |
490 | { | |
491 | unsigned size; | |
492 | uschar * buf; | |
493 | ||
494 | if (smtp_inptr >= smtp_inend) | |
495 | if (!smtp_refill(*len)) | |
496 | { *len = 0; return NULL; } | |
497 | ||
498 | if ((size = smtp_inend - smtp_inptr) > *len) size = *len; | |
499 | buf = smtp_inptr; | |
500 | smtp_inptr += size; | |
501 | *len = size; | |
502 | return buf; | |
503 | } | |
504 | ||
584e96c6 JH |
505 | void |
506 | smtp_get_cache(void) | |
507 | { | |
9960d1e5 | 508 | #ifndef DISABLE_DKIM |
584e96c6 JH |
509 | int n = smtp_inend - smtp_inptr; |
510 | if (n > 0) | |
511 | dkim_exim_verify_feed(smtp_inptr, n); | |
584e96c6 | 512 | #endif |
9960d1e5 | 513 | } |
059ec3d9 PH |
514 | |
515 | ||
7e3ce68e JH |
516 | /* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the |
517 | previous BDAT chunk and getting new ones when we run out. Uses the | |
518 | underlying smtp_getc or tls_getc both for that and for getting the | |
519 | (buffered) data byte. EOD signals (an expected) no further data. | |
520 | ERR signals a protocol error, and EOF a closed input stream. | |
521 | ||
522 | Called from read_bdat_smtp() in receive.c for the message body, but also | |
523 | by the headers read loop in receive_msg(); manipulates chunking_state | |
524 | to handle the BDAT command/response. | |
525 | Placed here due to the correlation with the above smtp_getc(), which it wraps, | |
526 | and also by the need to do smtp command/response handling. | |
527 | ||
bd8fbe36 | 528 | Arguments: lim (ignored) |
7e3ce68e JH |
529 | Returns: the next character or ERR, EOD or EOF |
530 | */ | |
531 | ||
532 | int | |
bd8fbe36 | 533 | bdat_getc(unsigned lim) |
7e3ce68e JH |
534 | { |
535 | uschar * user_msg = NULL; | |
536 | uschar * log_msg; | |
537 | ||
538 | for(;;) | |
539 | { | |
79de4f37 JH |
540 | #ifndef DISABLE_DKIM |
541 | BOOL dkim_save; | |
542 | #endif | |
543 | ||
bd8fbe36 JH |
544 | if (chunking_data_left > 0) |
545 | return lwr_receive_getc(chunking_data_left--); | |
7e3ce68e JH |
546 | |
547 | receive_getc = lwr_receive_getc; | |
0d81dabc | 548 | receive_getbuf = lwr_receive_getbuf; |
7e3ce68e | 549 | receive_ungetc = lwr_receive_ungetc; |
bd8fbe36 | 550 | #ifndef DISABLE_DKIM |
79de4f37 | 551 | dkim_save = dkim_collect_input; |
bd8fbe36 JH |
552 | dkim_collect_input = FALSE; |
553 | #endif | |
7e3ce68e | 554 | |
f4630439 JH |
555 | /* Unless PIPELINING was offered, there should be no next command |
556 | until after we ack that chunk */ | |
557 | ||
558 | if (!pipelining_advertised && !check_sync()) | |
559 | { | |
40525d07 JH |
560 | unsigned n = smtp_inend - smtp_inptr; |
561 | if (n > 32) n = 32; | |
562 | ||
f4630439 JH |
563 | incomplete_transaction_log(US"sync failure"); |
564 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error " | |
565 | "(next input sent too soon: pipelining was not advertised): " | |
566 | "rejected \"%s\" %s next input=\"%s\"", | |
567 | smtp_cmd_buffer, host_and_ident(TRUE), | |
40525d07 | 568 | string_printing(string_copyn(smtp_inptr, n))); |
f4630439 JH |
569 | (void) synprot_error(L_smtp_protocol_error, 554, NULL, |
570 | US"SMTP synchronization error"); | |
571 | goto repeat_until_rset; | |
572 | } | |
573 | ||
7e3ce68e JH |
574 | /* If not the last, ack the received chunk. The last response is delayed |
575 | until after the data ACL decides on it */ | |
7e3ce68e JH |
576 | |
577 | if (chunking_state == CHUNKING_LAST) | |
584e96c6 JH |
578 | { |
579 | #ifndef DISABLE_DKIM | |
e983e85a | 580 | dkim_exim_verify_feed(NULL, 0); /* notify EOD */ |
584e96c6 | 581 | #endif |
7e3ce68e | 582 | return EOD; |
584e96c6 | 583 | } |
7e3ce68e | 584 | |
925ac8e4 | 585 | smtp_printf("250 %u byte chunk received\r\n", FALSE, chunking_datasize); |
bd8fbe36 JH |
586 | chunking_state = CHUNKING_OFFERED; |
587 | DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state); | |
7e3ce68e JH |
588 | |
589 | /* Expect another BDAT cmd from input. RFC 3030 says nothing about | |
590 | QUIT, RSET or NOOP but handling them seems obvious */ | |
591 | ||
592 | next_cmd: | |
bd8fbe36 | 593 | switch(smtp_read_command(TRUE, 1)) |
7e3ce68e JH |
594 | { |
595 | default: | |
596 | (void) synprot_error(L_smtp_protocol_error, 503, NULL, | |
597 | US"only BDAT permissible after non-LAST BDAT"); | |
598 | ||
599 | repeat_until_rset: | |
bd8fbe36 | 600 | switch(smtp_read_command(TRUE, 1)) |
7e3ce68e JH |
601 | { |
602 | case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */ | |
603 | case EOF_CMD: return EOF; | |
604 | case RSET_CMD: smtp_rset_handler(); return ERR; | |
605 | default: if (synprot_error(L_smtp_protocol_error, 503, NULL, | |
606 | US"only RSET accepted now") > 0) | |
607 | return EOF; | |
608 | goto repeat_until_rset; | |
609 | } | |
610 | ||
611 | case QUIT_CMD: | |
612 | smtp_quit_handler(&user_msg, &log_msg); | |
613 | /*FALLTHROUGH*/ | |
614 | case EOF_CMD: | |
615 | return EOF; | |
616 | ||
617 | case RSET_CMD: | |
618 | smtp_rset_handler(); | |
619 | return ERR; | |
620 | ||
621 | case NOOP_CMD: | |
622 | HAD(SCH_NOOP); | |
925ac8e4 | 623 | smtp_printf("250 OK\r\n", FALSE); |
7e3ce68e JH |
624 | goto next_cmd; |
625 | ||
626 | case BDAT_CMD: | |
627 | { | |
628 | int n; | |
629 | ||
630 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) | |
631 | { | |
632 | (void) synprot_error(L_smtp_protocol_error, 501, NULL, | |
633 | US"missing size for BDAT command"); | |
634 | return ERR; | |
635 | } | |
636 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
637 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
638 | chunking_data_left = chunking_datasize; | |
bd8fbe36 JH |
639 | DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n", |
640 | (int)chunking_state, chunking_data_left); | |
7e3ce68e JH |
641 | |
642 | if (chunking_datasize == 0) | |
643 | if (chunking_state == CHUNKING_LAST) | |
644 | return EOD; | |
645 | else | |
646 | { | |
647 | (void) synprot_error(L_smtp_protocol_error, 504, NULL, | |
648 | US"zero size for BDAT command"); | |
649 | goto repeat_until_rset; | |
650 | } | |
651 | ||
652 | receive_getc = bdat_getc; | |
0d81dabc | 653 | receive_getbuf = bdat_getbuf; |
7e3ce68e | 654 | receive_ungetc = bdat_ungetc; |
bd8fbe36 | 655 | #ifndef DISABLE_DKIM |
79de4f37 | 656 | dkim_collect_input = dkim_save; |
bd8fbe36 | 657 | #endif |
7e3ce68e JH |
658 | break; /* to top of main loop */ |
659 | } | |
660 | } | |
661 | } | |
662 | } | |
663 | ||
0d81dabc JH |
664 | uschar * |
665 | bdat_getbuf(unsigned * len) | |
666 | { | |
667 | uschar * buf; | |
668 | ||
669 | if (chunking_data_left <= 0) | |
670 | { *len = 0; return NULL; } | |
671 | ||
672 | if (*len > chunking_data_left) *len = chunking_data_left; | |
673 | buf = lwr_receive_getbuf(len); /* Either smtp_getbuf or tls_getbuf */ | |
674 | chunking_data_left -= *len; | |
675 | return buf; | |
676 | } | |
677 | ||
1ebe15c3 | 678 | void |
45bd315d JH |
679 | bdat_flush_data(void) |
680 | { | |
0d81dabc JH |
681 | unsigned n = chunking_data_left; |
682 | (void) bdat_getbuf(&n); | |
45bd315d JH |
683 | |
684 | receive_getc = lwr_receive_getc; | |
0d81dabc | 685 | receive_getbuf = lwr_receive_getbuf; |
45bd315d JH |
686 | receive_ungetc = lwr_receive_ungetc; |
687 | ||
688 | if (chunking_state != CHUNKING_LAST) | |
bd8fbe36 | 689 | { |
45bd315d | 690 | chunking_state = CHUNKING_OFFERED; |
bd8fbe36 JH |
691 | DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state); |
692 | } | |
45bd315d JH |
693 | } |
694 | ||
7e3ce68e JH |
695 | |
696 | ||
697 | ||
059ec3d9 PH |
698 | /************************************************* |
699 | * SMTP version of ungetc() * | |
700 | *************************************************/ | |
701 | ||
702 | /* Puts a character back in the input buffer. Only ever | |
703 | called once. | |
704 | ||
705 | Arguments: | |
706 | ch the character | |
707 | ||
708 | Returns: the character | |
709 | */ | |
710 | ||
711 | int | |
712 | smtp_ungetc(int ch) | |
713 | { | |
7e3ce68e | 714 | *--smtp_inptr = ch; |
059ec3d9 PH |
715 | return ch; |
716 | } | |
717 | ||
718 | ||
7e3ce68e JH |
719 | int |
720 | bdat_ungetc(int ch) | |
721 | { | |
722 | chunking_data_left++; | |
723 | return lwr_receive_ungetc(ch); | |
724 | } | |
725 | ||
059ec3d9 PH |
726 | |
727 | ||
728 | /************************************************* | |
729 | * SMTP version of feof() * | |
730 | *************************************************/ | |
731 | ||
732 | /* Tests for a previous EOF | |
733 | ||
734 | Arguments: none | |
735 | Returns: non-zero if the eof flag is set | |
736 | */ | |
737 | ||
738 | int | |
739 | smtp_feof(void) | |
740 | { | |
741 | return smtp_had_eof; | |
742 | } | |
743 | ||
744 | ||
745 | ||
746 | ||
747 | /************************************************* | |
748 | * SMTP version of ferror() * | |
749 | *************************************************/ | |
750 | ||
751 | /* Tests for a previous read error, and returns with errno | |
752 | restored to what it was when the error was detected. | |
753 | ||
754 | Arguments: none | |
755 | Returns: non-zero if the error flag is set | |
756 | */ | |
757 | ||
758 | int | |
759 | smtp_ferror(void) | |
760 | { | |
761 | errno = smtp_had_error; | |
762 | return smtp_had_error; | |
763 | } | |
764 | ||
765 | ||
766 | ||
58eb016e PH |
767 | /************************************************* |
768 | * Test for characters in the SMTP buffer * | |
769 | *************************************************/ | |
770 | ||
771 | /* Used at the end of a message | |
772 | ||
773 | Arguments: none | |
774 | Returns: TRUE/FALSE | |
775 | */ | |
776 | ||
777 | BOOL | |
778 | smtp_buffered(void) | |
779 | { | |
780 | return smtp_inptr < smtp_inend; | |
781 | } | |
782 | ||
783 | ||
059ec3d9 PH |
784 | |
785 | /************************************************* | |
786 | * Write formatted string to SMTP channel * | |
787 | *************************************************/ | |
788 | ||
789 | /* This is a separate function so that we don't have to repeat everything for | |
790 | TLS support or debugging. It is global so that the daemon and the | |
791 | authentication functions can use it. It does not return any error indication, | |
792 | because major problems such as dropped connections won't show up till an output | |
793 | flush for non-TLS connections. The smtp_fflush() function is available for | |
794 | checking that: for convenience, TLS output errors are remembered here so that | |
795 | they are also picked up later by smtp_fflush(). | |
796 | ||
797 | Arguments: | |
798 | format format string | |
925ac8e4 | 799 | more further data expected |
059ec3d9 PH |
800 | ... optional arguments |
801 | ||
802 | Returns: nothing | |
803 | */ | |
804 | ||
805 | void | |
925ac8e4 | 806 | smtp_printf(const char *format, BOOL more, ...) |
059ec3d9 PH |
807 | { |
808 | va_list ap; | |
809 | ||
925ac8e4 JH |
810 | va_start(ap, more); |
811 | smtp_vprintf(format, more, ap); | |
ce552449 NM |
812 | va_end(ap); |
813 | } | |
814 | ||
815 | /* This is split off so that verify.c:respond_printf() can, in effect, call | |
816 | smtp_printf(), bearing in mind that in C a vararg function can't directly | |
fb08281f | 817 | call another vararg function, only a function which accepts a va_list. */ |
ce552449 NM |
818 | |
819 | void | |
925ac8e4 | 820 | smtp_vprintf(const char *format, BOOL more, va_list ap) |
ce552449 | 821 | { |
fb08281f DW |
822 | BOOL yield; |
823 | ||
824 | yield = string_vformat(big_buffer, big_buffer_size, format, ap); | |
ce552449 | 825 | |
059ec3d9 PH |
826 | DEBUG(D_receive) |
827 | { | |
fb08281f DW |
828 | void *reset_point = store_get(0); |
829 | uschar *msg_copy, *cr, *end; | |
830 | msg_copy = string_copy(big_buffer); | |
831 | end = msg_copy + Ustrlen(msg_copy); | |
832 | while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */ | |
833 | memmove(cr, cr + 1, (end--) - cr); | |
834 | debug_printf("SMTP>> %s", msg_copy); | |
835 | store_reset(reset_point); | |
059ec3d9 PH |
836 | } |
837 | ||
fb08281f | 838 | if (!yield) |
2679d413 PH |
839 | { |
840 | log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()"); | |
841 | smtp_closedown(US"Unexpected error"); | |
842 | exim_exit(EXIT_FAILURE); | |
843 | } | |
2679d413 PH |
844 | |
845 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs | |
846 | have had the same. Note: this code is also present in smtp_respond(). It would | |
847 | be tidier to have it only in one place, but when it was added, it was easier to | |
848 | do it that way, so as not to have to mess with the code for the RCPT command, | |
849 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
850 | ||
851 | if (rcpt_in_progress) | |
852 | { | |
853 | if (rcpt_smtp_response == NULL) | |
854 | rcpt_smtp_response = string_copy(big_buffer); | |
855 | else if (rcpt_smtp_response_same && | |
856 | Ustrcmp(rcpt_smtp_response, big_buffer) != 0) | |
857 | rcpt_smtp_response_same = FALSE; | |
858 | rcpt_in_progress = FALSE; | |
859 | } | |
059ec3d9 | 860 | |
2679d413 | 861 | /* Now write the string */ |
059ec3d9 PH |
862 | |
863 | #ifdef SUPPORT_TLS | |
817d9f57 | 864 | if (tls_in.active >= 0) |
059ec3d9 | 865 | { |
925ac8e4 | 866 | if (tls_write(TRUE, big_buffer, Ustrlen(big_buffer), more) < 0) |
817d9f57 | 867 | smtp_write_error = -1; |
059ec3d9 PH |
868 | } |
869 | else | |
870 | #endif | |
871 | ||
2679d413 | 872 | if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1; |
059ec3d9 PH |
873 | } |
874 | ||
875 | ||
876 | ||
877 | /************************************************* | |
878 | * Flush SMTP out and check for error * | |
879 | *************************************************/ | |
880 | ||
881 | /* This function isn't currently used within Exim (it detects errors when it | |
882 | tries to read the next SMTP input), but is available for use in local_scan(). | |
883 | For non-TLS connections, it flushes the output and checks for errors. For | |
884 | TLS-connections, it checks for a previously-detected TLS write error. | |
885 | ||
886 | Arguments: none | |
887 | Returns: 0 for no error; -1 after an error | |
888 | */ | |
889 | ||
890 | int | |
891 | smtp_fflush(void) | |
892 | { | |
817d9f57 | 893 | if (tls_in.active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1; |
059ec3d9 PH |
894 | return smtp_write_error; |
895 | } | |
896 | ||
897 | ||
898 | ||
899 | /************************************************* | |
900 | * SMTP command read timeout * | |
901 | *************************************************/ | |
902 | ||
903 | /* Signal handler for timing out incoming SMTP commands. This attempts to | |
904 | finish off tidily. | |
905 | ||
906 | Argument: signal number (SIGALRM) | |
907 | Returns: nothing | |
908 | */ | |
909 | ||
910 | static void | |
911 | command_timeout_handler(int sig) | |
912 | { | |
913 | sig = sig; /* Keep picky compilers happy */ | |
914 | log_write(L_lost_incoming_connection, | |
915 | LOG_MAIN, "SMTP command timeout on%s connection from %s", | |
817d9f57 | 916 | (tls_in.active >= 0)? " TLS" : "", |
059ec3d9 PH |
917 | host_and_ident(FALSE)); |
918 | if (smtp_batched_input) | |
919 | moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */ | |
8f128379 PH |
920 | smtp_notquit_exit(US"command-timeout", US"421", |
921 | US"%s: SMTP command timeout - closing connection", smtp_active_hostname); | |
059ec3d9 PH |
922 | exim_exit(EXIT_FAILURE); |
923 | } | |
924 | ||
925 | ||
926 | ||
927 | /************************************************* | |
928 | * SIGTERM received * | |
929 | *************************************************/ | |
930 | ||
931 | /* Signal handler for handling SIGTERM. Again, try to finish tidily. | |
932 | ||
933 | Argument: signal number (SIGTERM) | |
934 | Returns: nothing | |
935 | */ | |
936 | ||
937 | static void | |
938 | command_sigterm_handler(int sig) | |
939 | { | |
940 | sig = sig; /* Keep picky compilers happy */ | |
941 | log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info()); | |
942 | if (smtp_batched_input) | |
943 | moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */ | |
8f128379 PH |
944 | smtp_notquit_exit(US"signal-exit", US"421", |
945 | US"%s: Service not available - closing connection", smtp_active_hostname); | |
059ec3d9 PH |
946 | exim_exit(EXIT_FAILURE); |
947 | } | |
948 | ||
949 | ||
950 | ||
a14e5636 | 951 | |
cee5f132 | 952 | #ifdef SUPPORT_PROXY |
a3bddaa8 TL |
953 | /************************************************* |
954 | * Restore socket timeout to previous value * | |
955 | *************************************************/ | |
956 | /* If the previous value was successfully retrieved, restore | |
957 | it before returning control to the non-proxy routines | |
958 | ||
959 | Arguments: fd - File descriptor for input | |
960 | get_ok - Successfully retrieved previous values | |
961 | tvtmp - Time struct with previous values | |
962 | vslen - Length of time struct | |
963 | Returns: none | |
964 | */ | |
965 | static void | |
f267271d | 966 | restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen) |
a3bddaa8 TL |
967 | { |
968 | if (get_ok == 0) | |
f267271d | 969 | (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen); |
a3bddaa8 TL |
970 | } |
971 | ||
a3c86431 TL |
972 | /************************************************* |
973 | * Check if host is required proxy host * | |
974 | *************************************************/ | |
975 | /* The function determines if inbound host will be a regular smtp host | |
1811cb4c JH |
976 | or if it is configured that it must use Proxy Protocol. A local |
977 | connection cannot. | |
a3c86431 TL |
978 | |
979 | Arguments: none | |
980 | Returns: bool | |
981 | */ | |
982 | ||
983 | static BOOL | |
984 | check_proxy_protocol_host() | |
985 | { | |
986 | int rc; | |
a3c86431 | 987 | |
1811cb4c JH |
988 | if ( sender_host_address |
989 | && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL, | |
990 | sender_host_address, NULL)) == OK) | |
a3c86431 TL |
991 | { |
992 | DEBUG(D_receive) | |
993 | debug_printf("Detected proxy protocol configured host\n"); | |
994 | proxy_session = TRUE; | |
995 | } | |
996 | return proxy_session; | |
997 | } | |
998 | ||
999 | ||
3f251b3c PP |
1000 | /************************************************* |
1001 | * Read data until newline or end of buffer * | |
1002 | *************************************************/ | |
1003 | /* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't | |
1004 | read an entire buffer and assume there will be nothing past a proxy protocol | |
1005 | header. Our approach normally is to use stdio, but again that relies upon | |
1006 | "STARTTLS\r\n" and a server response before the client starts TLS handshake, or | |
1007 | reading _nothing_ before client TLS handshake. So we don't want to use the | |
1008 | usual buffering reads which may read enough to block TLS starting. | |
1009 | ||
1010 | So unfortunately we're down to "read one byte at a time, with a syscall each, | |
1011 | and expect a little overhead", for all proxy-opened connections which are v1, | |
1012 | just to handle the TLS-on-connect case. Since SSL functions wrap the | |
1013 | underlying fd, we can't assume that we can feed them any already-read content. | |
1014 | ||
1015 | We need to know where to read to, the max capacity, and we'll read until we | |
1016 | get a CR and one more character. Let the caller scream if it's CR+!LF. | |
1017 | ||
1018 | Return the amount read. | |
1019 | */ | |
1020 | ||
1021 | static int | |
da88acae | 1022 | swallow_until_crlf(int fd, uschar *base, int already, int capacity) |
3f251b3c | 1023 | { |
2c0f3ea1 JH |
1024 | uschar *to = base + already; |
1025 | uschar *cr; | |
1026 | int have = 0; | |
1027 | int ret; | |
1028 | int last = 0; | |
1029 | ||
1030 | /* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read | |
1031 | up through the \r; for the _normal_ case, we haven't yet seen the \r. */ | |
da88acae | 1032 | |
2c0f3ea1 JH |
1033 | cr = memchr(base, '\r', already); |
1034 | if (cr != NULL) | |
1035 | { | |
1036 | if ((cr - base) < already - 1) | |
da88acae | 1037 | { |
2c0f3ea1 JH |
1038 | /* \r and presumed \n already within what we have; probably not |
1039 | actually proxy protocol, but abort cleanly. */ | |
1040 | return 0; | |
da88acae | 1041 | } |
2c0f3ea1 JH |
1042 | /* \r is last character read, just need one more. */ |
1043 | last = 1; | |
1044 | } | |
1045 | ||
1046 | while (capacity > 0) | |
1047 | { | |
1048 | do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR); | |
1049 | if (ret == -1) | |
1050 | return -1; | |
1051 | have++; | |
1052 | if (last) | |
1053 | return have; | |
1054 | if (*to == '\r') | |
1055 | last = 1; | |
1056 | capacity--; | |
1057 | to++; | |
1058 | } | |
1059 | ||
1060 | /* reached end without having room for a final newline, abort */ | |
1061 | errno = EOVERFLOW; | |
1062 | return -1; | |
3f251b3c PP |
1063 | } |
1064 | ||
a3c86431 TL |
1065 | /************************************************* |
1066 | * Setup host for proxy protocol * | |
1067 | *************************************************/ | |
1068 | /* The function configures the connection based on a header from the | |
1069 | inbound host to use Proxy Protocol. The specification is very exact | |
1070 | so exit with an error if do not find the exact required pieces. This | |
1071 | includes an incorrect number of spaces separating args. | |
1072 | ||
1073 | Arguments: none | |
f267271d | 1074 | Returns: Boolean success |
a3c86431 TL |
1075 | */ |
1076 | ||
1811cb4c | 1077 | static void |
a3c86431 TL |
1078 | setup_proxy_protocol_host() |
1079 | { | |
1080 | union { | |
1081 | struct { | |
1082 | uschar line[108]; | |
1083 | } v1; | |
1084 | struct { | |
1085 | uschar sig[12]; | |
36719342 TL |
1086 | uint8_t ver_cmd; |
1087 | uint8_t fam; | |
1088 | uint16_t len; | |
a3c86431 TL |
1089 | union { |
1090 | struct { /* TCP/UDP over IPv4, len = 12 */ | |
1091 | uint32_t src_addr; | |
1092 | uint32_t dst_addr; | |
1093 | uint16_t src_port; | |
1094 | uint16_t dst_port; | |
1095 | } ip4; | |
1096 | struct { /* TCP/UDP over IPv6, len = 36 */ | |
1097 | uint8_t src_addr[16]; | |
1098 | uint8_t dst_addr[16]; | |
1099 | uint16_t src_port; | |
1100 | uint16_t dst_port; | |
1101 | } ip6; | |
1102 | struct { /* AF_UNIX sockets, len = 216 */ | |
1103 | uschar src_addr[108]; | |
1104 | uschar dst_addr[108]; | |
1105 | } unx; | |
1106 | } addr; | |
1107 | } v2; | |
1108 | } hdr; | |
1109 | ||
eb57651e TL |
1110 | /* Temp variables used in PPv2 address:port parsing */ |
1111 | uint16_t tmpport; | |
1112 | char tmpip[INET_ADDRSTRLEN]; | |
1113 | struct sockaddr_in tmpaddr; | |
1114 | char tmpip6[INET6_ADDRSTRLEN]; | |
1115 | struct sockaddr_in6 tmpaddr6; | |
1116 | ||
da88acae PP |
1117 | /* We can't read "all data until end" because while SMTP is |
1118 | server-speaks-first, the TLS handshake is client-speaks-first, so for | |
1119 | TLS-on-connect ports the proxy protocol header will usually be immediately | |
1120 | followed by a TLS handshake, and with N TLS libraries, we can't reliably | |
1121 | reinject data for reading by those. So instead we first read "enough to be | |
1122 | safely read within the header, and figure out how much more to read". | |
1123 | For v1 we will later read to the end-of-line, for v2 we will read based upon | |
1124 | the stated length. | |
1125 | ||
1126 | The v2 sig is 12 octets, and another 4 gets us the length, so we know how much | |
1127 | data is needed total. For v1, where the line looks like: | |
1128 | PROXY TCPn L3src L3dest SrcPort DestPort \r\n | |
1129 | ||
1130 | However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets. | |
1131 | We seem to support that. So, if we read 14 octets then we can tell if we're | |
1132 | v2 or v1. If we're v1, we can continue reading as normal. | |
1133 | ||
1134 | If we're v2, we can't slurp up the entire header. We need the length in the | |
1135 | 15th & 16th octets, then to read everything after that. | |
1136 | ||
1137 | So to safely handle v1 and v2, with client-sent-first supported correctly, | |
1138 | we have to do a minimum of 3 read calls, not 1. Eww. | |
1139 | */ | |
1140 | ||
1141 | #define PROXY_INITIAL_READ 14 | |
1142 | #define PROXY_V2_HEADER_SIZE 16 | |
1143 | #if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE | |
1144 | # error Code bug in sizes of data to read for proxy usage | |
1145 | #endif | |
1146 | ||
eb57651e | 1147 | int get_ok = 0; |
f267271d JH |
1148 | int size, ret; |
1149 | int fd = fileno(smtp_in); | |
36719342 | 1150 | const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A"; |
9e7e0f6a | 1151 | uschar * iptype; /* To display debug info */ |
a3c86431 | 1152 | struct timeval tv; |
a3bddaa8 | 1153 | struct timeval tvtmp; |
f267271d | 1154 | socklen_t vslen = sizeof(struct timeval); |
1811cb4c | 1155 | BOOL yield = FALSE; |
a3c86431 | 1156 | |
a3bddaa8 | 1157 | /* Save current socket timeout values */ |
f267271d | 1158 | get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen); |
a3bddaa8 | 1159 | |
a3c86431 TL |
1160 | /* Proxy Protocol host must send header within a short time |
1161 | (default 3 seconds) or it's considered invalid */ | |
1162 | tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC; | |
1163 | tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC; | |
f267271d | 1164 | if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0) |
1811cb4c | 1165 | goto bad; |
a3bddaa8 | 1166 | |
a3c86431 TL |
1167 | do |
1168 | { | |
eb57651e | 1169 | /* The inbound host was declared to be a Proxy Protocol host, so |
2c0f3ea1 JH |
1170 | don't do a PEEK into the data, actually slurp up enough to be |
1171 | "safe". Can't take it all because TLS-on-connect clients follow | |
1172 | immediately with TLS handshake. */ | |
3f251b3c | 1173 | ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0); |
a3c86431 TL |
1174 | } |
1175 | while (ret == -1 && errno == EINTR); | |
1176 | ||
1177 | if (ret == -1) | |
f267271d | 1178 | goto proxyfail; |
a3c86431 | 1179 | |
da88acae PP |
1180 | /* For v2, handle reading the length, and then the rest. */ |
1181 | if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0)) | |
a3c86431 | 1182 | { |
da88acae PP |
1183 | int retmore; |
1184 | uint8_t ver; | |
1185 | ||
1186 | /* First get the length fields. */ | |
1187 | do | |
1188 | { | |
1189 | retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0); | |
1190 | } while (retmore == -1 && errno == EINTR); | |
1191 | if (retmore == -1) | |
3f251b3c | 1192 | goto proxyfail; |
da88acae | 1193 | ret += retmore; |
3f251b3c PP |
1194 | |
1195 | ver = (hdr.v2.ver_cmd & 0xf0) >> 4; | |
36719342 TL |
1196 | |
1197 | /* May 2014: haproxy combined the version and command into one byte to | |
2c0f3ea1 JH |
1198 | allow two full bytes for the length field in order to proxy SSL |
1199 | connections. SSL Proxy is not supported in this version of Exim, but | |
1200 | must still separate values here. */ | |
36719342 TL |
1201 | |
1202 | if (ver != 0x02) | |
1203 | { | |
1204 | DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver); | |
1205 | goto proxyfail; | |
1206 | } | |
da88acae | 1207 | |
36719342 | 1208 | /* The v2 header will always be 16 bytes per the spec. */ |
5d036699 | 1209 | size = 16 + ntohs(hdr.v2.len); |
da88acae PP |
1210 | DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n", |
1211 | size, (int)sizeof(hdr)); | |
1212 | ||
1213 | /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total | |
1214 | amount that we need. Double-check that the size is not unreasonable, then | |
1215 | get the rest. */ | |
1216 | if (size > sizeof(hdr)) | |
a3c86431 | 1217 | { |
da88acae | 1218 | DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n"); |
a3c86431 TL |
1219 | goto proxyfail; |
1220 | } | |
da88acae PP |
1221 | |
1222 | do | |
1223 | { | |
1224 | do | |
1225 | { | |
1226 | retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0); | |
1227 | } while (retmore == -1 && errno == EINTR); | |
1228 | if (retmore == -1) | |
1229 | goto proxyfail; | |
1230 | ret += retmore; | |
1231 | DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size); | |
1232 | } while (ret < size); | |
1233 | ||
1234 | } /* end scope for getting rest of data for v2 */ | |
1235 | ||
1236 | /* At this point: if PROXYv2, we've read the exact size required for all data; | |
1237 | if PROXYv1 then we've read "less than required for any valid line" and should | |
1238 | read the rest". */ | |
1239 | ||
1240 | if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0) | |
1241 | { | |
1242 | uint8_t cmd = (hdr.v2.ver_cmd & 0x0f); | |
1243 | ||
36719342 | 1244 | switch (cmd) |
a3c86431 TL |
1245 | { |
1246 | case 0x01: /* PROXY command */ | |
1247 | switch (hdr.v2.fam) | |
1248 | { | |
eb57651e TL |
1249 | case 0x11: /* TCPv4 address type */ |
1250 | iptype = US"IPv4"; | |
1251 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr; | |
5d036699 JH |
1252 | inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip)); |
1253 | if (!string_is_ip_address(US tmpip, NULL)) | |
eb57651e TL |
1254 | { |
1255 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
f267271d | 1256 | goto proxyfail; |
eb57651e | 1257 | } |
e6d2a989 | 1258 | proxy_local_address = sender_host_address; |
eb57651e TL |
1259 | sender_host_address = string_copy(US tmpip); |
1260 | tmpport = ntohs(hdr.v2.addr.ip4.src_port); | |
e6d2a989 | 1261 | proxy_local_port = sender_host_port; |
eb57651e TL |
1262 | sender_host_port = tmpport; |
1263 | /* Save dest ip/port */ | |
1264 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr; | |
5d036699 JH |
1265 | inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip)); |
1266 | if (!string_is_ip_address(US tmpip, NULL)) | |
eb57651e TL |
1267 | { |
1268 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
f267271d | 1269 | goto proxyfail; |
eb57651e | 1270 | } |
7a2fa0bc | 1271 | proxy_external_address = string_copy(US tmpip); |
eb57651e | 1272 | tmpport = ntohs(hdr.v2.addr.ip4.dst_port); |
7a2fa0bc | 1273 | proxy_external_port = tmpport; |
a3c86431 | 1274 | goto done; |
eb57651e TL |
1275 | case 0x21: /* TCPv6 address type */ |
1276 | iptype = US"IPv6"; | |
1277 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16); | |
5d036699 JH |
1278 | inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6)); |
1279 | if (!string_is_ip_address(US tmpip6, NULL)) | |
eb57651e TL |
1280 | { |
1281 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
f267271d | 1282 | goto proxyfail; |
eb57651e | 1283 | } |
e6d2a989 | 1284 | proxy_local_address = sender_host_address; |
eb57651e TL |
1285 | sender_host_address = string_copy(US tmpip6); |
1286 | tmpport = ntohs(hdr.v2.addr.ip6.src_port); | |
e6d2a989 | 1287 | proxy_local_port = sender_host_port; |
eb57651e TL |
1288 | sender_host_port = tmpport; |
1289 | /* Save dest ip/port */ | |
1290 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16); | |
5d036699 JH |
1291 | inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6)); |
1292 | if (!string_is_ip_address(US tmpip6, NULL)) | |
eb57651e TL |
1293 | { |
1294 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
f267271d | 1295 | goto proxyfail; |
eb57651e | 1296 | } |
7a2fa0bc | 1297 | proxy_external_address = string_copy(US tmpip6); |
eb57651e | 1298 | tmpport = ntohs(hdr.v2.addr.ip6.dst_port); |
7a2fa0bc | 1299 | proxy_external_port = tmpport; |
a3c86431 | 1300 | goto done; |
eb57651e TL |
1301 | default: |
1302 | DEBUG(D_receive) | |
1303 | debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n", | |
1304 | hdr.v2.fam); | |
1305 | goto proxyfail; | |
a3c86431 TL |
1306 | } |
1307 | /* Unsupported protocol, keep local connection address */ | |
1308 | break; | |
1309 | case 0x00: /* LOCAL command */ | |
1310 | /* Keep local connection address for LOCAL */ | |
9e7e0f6a | 1311 | iptype = US"local"; |
a3c86431 TL |
1312 | break; |
1313 | default: | |
eb57651e | 1314 | DEBUG(D_receive) |
36719342 | 1315 | debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd); |
a3c86431 TL |
1316 | goto proxyfail; |
1317 | } | |
1318 | } | |
5d036699 | 1319 | else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0) |
a3c86431 | 1320 | { |
3f251b3c PP |
1321 | uschar *p; |
1322 | uschar *end; | |
a3c86431 TL |
1323 | uschar *sp; /* Utility variables follow */ |
1324 | int tmp_port; | |
3f251b3c | 1325 | int r2; |
a3c86431 TL |
1326 | char *endc; |
1327 | ||
3f251b3c | 1328 | /* get the rest of the line */ |
da88acae | 1329 | r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret); |
3f251b3c PP |
1330 | if (r2 == -1) |
1331 | goto proxyfail; | |
1332 | ret += r2; | |
1333 | ||
1334 | p = string_copy(hdr.v1.line); | |
1335 | end = memchr(p, '\r', ret - 1); | |
1336 | ||
da88acae | 1337 | if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n') |
a3c86431 TL |
1338 | { |
1339 | DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n"); | |
1340 | goto proxyfail; | |
1341 | } | |
1342 | *end = '\0'; /* Terminate the string */ | |
a5d4db40 | 1343 | size = end + 2 - p; /* Skip header + CRLF */ |
a3c86431 | 1344 | DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n"); |
3f251b3c | 1345 | DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size); |
a3c86431 | 1346 | /* Step through the string looking for the required fields. Ensure |
2c0f3ea1 | 1347 | strict adherence to required formatting, exit for any error. */ |
a3c86431 TL |
1348 | p += 5; |
1349 | if (!isspace(*(p++))) | |
1350 | { | |
1351 | DEBUG(D_receive) debug_printf("Missing space after PROXY command\n"); | |
1352 | goto proxyfail; | |
1353 | } | |
1354 | if (!Ustrncmp(p, CCS"TCP4", 4)) | |
1355 | iptype = US"IPv4"; | |
1356 | else if (!Ustrncmp(p,CCS"TCP6", 4)) | |
1357 | iptype = US"IPv6"; | |
1358 | else if (!Ustrncmp(p,CCS"UNKNOWN", 7)) | |
1359 | { | |
1360 | iptype = US"Unknown"; | |
1361 | goto done; | |
1362 | } | |
1363 | else | |
1364 | { | |
1365 | DEBUG(D_receive) debug_printf("Invalid TCP type\n"); | |
1366 | goto proxyfail; | |
1367 | } | |
1368 | ||
1369 | p += Ustrlen(iptype); | |
1370 | if (!isspace(*(p++))) | |
1371 | { | |
1372 | DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n"); | |
1373 | goto proxyfail; | |
1374 | } | |
1375 | /* Find the end of the arg */ | |
1376 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1377 | { | |
1378 | DEBUG(D_receive) | |
1379 | debug_printf("Did not find proxied src %s\n", iptype); | |
1380 | goto proxyfail; | |
1381 | } | |
1382 | *sp = '\0'; | |
5d036699 | 1383 | if(!string_is_ip_address(p, NULL)) |
a3c86431 TL |
1384 | { |
1385 | DEBUG(D_receive) | |
1386 | debug_printf("Proxied src arg is not an %s address\n", iptype); | |
1387 | goto proxyfail; | |
1388 | } | |
e6d2a989 | 1389 | proxy_local_address = sender_host_address; |
a3c86431 TL |
1390 | sender_host_address = p; |
1391 | p = sp + 1; | |
1392 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1393 | { | |
1394 | DEBUG(D_receive) | |
1395 | debug_printf("Did not find proxy dest %s\n", iptype); | |
1396 | goto proxyfail; | |
1397 | } | |
1398 | *sp = '\0'; | |
5d036699 | 1399 | if(!string_is_ip_address(p, NULL)) |
a3c86431 TL |
1400 | { |
1401 | DEBUG(D_receive) | |
1402 | debug_printf("Proxy dest arg is not an %s address\n", iptype); | |
1403 | goto proxyfail; | |
1404 | } | |
7a2fa0bc | 1405 | proxy_external_address = p; |
a3c86431 TL |
1406 | p = sp + 1; |
1407 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1408 | { | |
1409 | DEBUG(D_receive) debug_printf("Did not find proxied src port\n"); | |
1410 | goto proxyfail; | |
1411 | } | |
1412 | *sp = '\0'; | |
5d036699 | 1413 | tmp_port = strtol(CCS p, &endc, 10); |
a3c86431 TL |
1414 | if (*endc || tmp_port == 0) |
1415 | { | |
1416 | DEBUG(D_receive) | |
1417 | debug_printf("Proxied src port '%s' not an integer\n", p); | |
1418 | goto proxyfail; | |
1419 | } | |
e6d2a989 | 1420 | proxy_local_port = sender_host_port; |
a3c86431 TL |
1421 | sender_host_port = tmp_port; |
1422 | p = sp + 1; | |
1423 | if ((sp = Ustrchr(p, '\0')) == NULL) | |
1424 | { | |
1425 | DEBUG(D_receive) debug_printf("Did not find proxy dest port\n"); | |
1426 | goto proxyfail; | |
1427 | } | |
5d036699 | 1428 | tmp_port = strtol(CCS p, &endc, 10); |
a3c86431 TL |
1429 | if (*endc || tmp_port == 0) |
1430 | { | |
1431 | DEBUG(D_receive) | |
1432 | debug_printf("Proxy dest port '%s' not an integer\n", p); | |
1433 | goto proxyfail; | |
1434 | } | |
7a2fa0bc | 1435 | proxy_external_port = tmp_port; |
a3c86431 | 1436 | /* Already checked for /r /n above. Good V1 header received. */ |
a3c86431 TL |
1437 | } |
1438 | else | |
1439 | { | |
1440 | /* Wrong protocol */ | |
eb57651e | 1441 | DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n"); |
da88acae | 1442 | (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret); |
a3c86431 TL |
1443 | goto proxyfail; |
1444 | } | |
1445 | ||
1811cb4c JH |
1446 | done: |
1447 | DEBUG(D_receive) | |
1448 | debug_printf("Valid %s sender from Proxy Protocol header\n", iptype); | |
1449 | yield = proxy_session; | |
1450 | ||
1451 | /* Don't flush any potential buffer contents. Any input on proxyfail | |
1452 | should cause a synchronization failure */ | |
1453 | ||
a3c86431 | 1454 | proxyfail: |
1811cb4c | 1455 | restore_socket_timeout(fd, get_ok, &tvtmp, vslen); |
a3c86431 | 1456 | |
1811cb4c JH |
1457 | bad: |
1458 | if (yield) | |
1459 | { | |
1460 | sender_host_name = NULL; | |
1461 | (void) host_name_lookup(); | |
1462 | host_build_sender_fullhost(); | |
1463 | } | |
1464 | else | |
1465 | { | |
1466 | proxy_session_failed = TRUE; | |
1467 | DEBUG(D_receive) | |
1468 | debug_printf("Failure to extract proxied host, only QUIT allowed\n"); | |
1469 | } | |
1470 | ||
1471 | return; | |
a3c86431 TL |
1472 | } |
1473 | #endif | |
1474 | ||
059ec3d9 PH |
1475 | /************************************************* |
1476 | * Read one command line * | |
1477 | *************************************************/ | |
1478 | ||
1479 | /* Strictly, SMTP commands coming over the net are supposed to end with CRLF. | |
1480 | There are sites that don't do this, and in any case internal SMTP probably | |
1481 | should check only for LF. Consequently, we check here for LF only. The line | |
1482 | ends up with [CR]LF removed from its end. If we get an overlong line, treat as | |
3ee512ff PH |
1483 | an unknown command. The command is read into the global smtp_cmd_buffer so that |
1484 | it is available via $smtp_command. | |
059ec3d9 PH |
1485 | |
1486 | The character reading routine sets up a timeout for each block actually read | |
1487 | from the input (which may contain more than one command). We set up a special | |
1488 | signal handler that closes down the session on a timeout. Control does not | |
1489 | return when it runs. | |
1490 | ||
1491 | Arguments: | |
bd8fbe36 JH |
1492 | check_sync if TRUE, check synchronization rules if global option is TRUE |
1493 | buffer_lim maximum to buffer in lower layer | |
059ec3d9 PH |
1494 | |
1495 | Returns: a code identifying the command (enumerated above) | |
1496 | */ | |
1497 | ||
1498 | static int | |
bd8fbe36 | 1499 | smtp_read_command(BOOL check_sync, unsigned buffer_lim) |
059ec3d9 PH |
1500 | { |
1501 | int c; | |
1502 | int ptr = 0; | |
1503 | smtp_cmd_list *p; | |
1504 | BOOL hadnull = FALSE; | |
1505 | ||
1506 | os_non_restarting_signal(SIGALRM, command_timeout_handler); | |
1507 | ||
bd8fbe36 | 1508 | while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF) |
059ec3d9 | 1509 | { |
bd8fbe36 | 1510 | if (ptr >= SMTP_CMD_BUFFER_SIZE) |
059ec3d9 PH |
1511 | { |
1512 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1513 | return OTHER_CMD; | |
1514 | } | |
1515 | if (c == 0) | |
1516 | { | |
1517 | hadnull = TRUE; | |
1518 | c = '?'; | |
1519 | } | |
3ee512ff | 1520 | smtp_cmd_buffer[ptr++] = c; |
059ec3d9 PH |
1521 | } |
1522 | ||
1523 | receive_linecount++; /* For BSMTP errors */ | |
1524 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1525 | ||
1526 | /* If hit end of file, return pseudo EOF command. Whether we have a | |
1527 | part-line already read doesn't matter, since this is an error state. */ | |
1528 | ||
1529 | if (c == EOF) return EOF_CMD; | |
1530 | ||
1531 | /* Remove any CR and white space at the end of the line, and terminate the | |
1532 | string. */ | |
1533 | ||
3ee512ff PH |
1534 | while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--; |
1535 | smtp_cmd_buffer[ptr] = 0; | |
059ec3d9 | 1536 | |
3ee512ff | 1537 | DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer); |
059ec3d9 PH |
1538 | |
1539 | /* NULLs are not allowed in SMTP commands */ | |
1540 | ||
1541 | if (hadnull) return BADCHAR_CMD; | |
1542 | ||
1543 | /* Scan command list and return identity, having set the data pointer | |
1544 | to the start of the actual data characters. Check for SMTP synchronization | |
1545 | if required. */ | |
1546 | ||
1547 | for (p = cmd_list; p < cmd_list_end; p++) | |
1548 | { | |
1811cb4c | 1549 | #ifdef SUPPORT_PROXY |
a3c86431 | 1550 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
1811cb4c JH |
1551 | if (proxy_session && proxy_session_failed && p->cmd != QUIT_CMD) |
1552 | continue; | |
1553 | #endif | |
2f460950 JH |
1554 | if ( p->len |
1555 | && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0 | |
1556 | && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */ | |
1557 | || smtp_cmd_buffer[p->len] == 0 | |
1558 | || smtp_cmd_buffer[p->len] == ' ' | |
1559 | ) ) | |
059ec3d9 PH |
1560 | { |
1561 | if (smtp_inptr < smtp_inend && /* Outstanding input */ | |
1562 | p->cmd < sync_cmd_limit && /* Command should sync */ | |
1563 | check_sync && /* Local flag set */ | |
1564 | smtp_enforce_sync && /* Global flag set */ | |
1565 | sender_host_address != NULL && /* Not local input */ | |
1566 | !sender_host_notsocket) /* Really is a socket */ | |
1567 | return BADSYN_CMD; | |
1568 | ||
ca86f471 PH |
1569 | /* The variables $smtp_command and $smtp_command_argument point into the |
1570 | unmodified input buffer. A copy of the latter is taken for actual | |
1571 | processing, so that it can be chopped up into separate parts if necessary, | |
1572 | for example, when processing a MAIL command options such as SIZE that can | |
1573 | follow the sender address. */ | |
059ec3d9 | 1574 | |
3ee512ff | 1575 | smtp_cmd_argument = smtp_cmd_buffer + p->len; |
ca86f471 PH |
1576 | while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++; |
1577 | Ustrcpy(smtp_data_buffer, smtp_cmd_argument); | |
1578 | smtp_cmd_data = smtp_data_buffer; | |
059ec3d9 PH |
1579 | |
1580 | /* Count non-mail commands from those hosts that are controlled in this | |
1581 | way. The default is all hosts. We don't waste effort checking the list | |
1582 | until we get a non-mail command, but then cache the result to save checking | |
1583 | again. If there's a DEFER while checking the host, assume it's in the list. | |
1584 | ||
1585 | Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the | |
1586 | start of each incoming message by fiddling with the value in the table. */ | |
1587 | ||
1588 | if (!p->is_mail_cmd) | |
1589 | { | |
1590 | if (count_nonmail == TRUE_UNSET) count_nonmail = | |
1591 | verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL; | |
1592 | if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail) | |
1593 | return TOO_MANY_NONMAIL_CMD; | |
1594 | } | |
1595 | ||
ca86f471 PH |
1596 | /* If there is data for a command that does not expect it, generate the |
1597 | error here. */ | |
059ec3d9 | 1598 | |
ca86f471 | 1599 | return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD; |
059ec3d9 PH |
1600 | } |
1601 | } | |
1602 | ||
cee5f132 | 1603 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
1604 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
1605 | if (proxy_session && proxy_session_failed) | |
1606 | return PROXY_FAIL_IGNORE_CMD; | |
1607 | #endif | |
1608 | ||
059ec3d9 PH |
1609 | /* Enforce synchronization for unknown commands */ |
1610 | ||
1611 | if (smtp_inptr < smtp_inend && /* Outstanding input */ | |
1612 | check_sync && /* Local flag set */ | |
1613 | smtp_enforce_sync && /* Global flag set */ | |
1614 | sender_host_address != NULL && /* Not local input */ | |
1615 | !sender_host_notsocket) /* Really is a socket */ | |
1616 | return BADSYN_CMD; | |
1617 | ||
1618 | return OTHER_CMD; | |
1619 | } | |
1620 | ||
1621 | ||
1622 | ||
1623 | /************************************************* | |
1624 | * Forced closedown of call * | |
1625 | *************************************************/ | |
1626 | ||
1627 | /* This function is called from log.c when Exim is dying because of a serious | |
1628 | disaster, and also from some other places. If an incoming non-batched SMTP | |
1629 | channel is open, it swallows the rest of the incoming message if in the DATA | |
1630 | phase, sends the reply string, and gives an error to all subsequent commands | |
1631 | except QUIT. The existence of an SMTP call is detected by the non-NULLness of | |
1632 | smtp_in. | |
1633 | ||
8f128379 PH |
1634 | Arguments: |
1635 | message SMTP reply string to send, excluding the code | |
1636 | ||
059ec3d9 PH |
1637 | Returns: nothing |
1638 | */ | |
1639 | ||
1640 | void | |
1641 | smtp_closedown(uschar *message) | |
1642 | { | |
1643 | if (smtp_in == NULL || smtp_batched_input) return; | |
1644 | receive_swallow_smtp(); | |
925ac8e4 | 1645 | smtp_printf("421 %s\r\n", FALSE, message); |
059ec3d9 | 1646 | |
bd8fbe36 | 1647 | for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) |
059ec3d9 | 1648 | { |
60d10ce7 JH |
1649 | case EOF_CMD: |
1650 | return; | |
059ec3d9 | 1651 | |
60d10ce7 | 1652 | case QUIT_CMD: |
925ac8e4 | 1653 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); |
60d10ce7 JH |
1654 | mac_smtp_fflush(); |
1655 | return; | |
059ec3d9 | 1656 | |
60d10ce7 | 1657 | case RSET_CMD: |
925ac8e4 | 1658 | smtp_printf("250 Reset OK\r\n", FALSE); |
60d10ce7 | 1659 | break; |
059ec3d9 | 1660 | |
60d10ce7 | 1661 | default: |
925ac8e4 | 1662 | smtp_printf("421 %s\r\n", FALSE, message); |
60d10ce7 | 1663 | break; |
059ec3d9 PH |
1664 | } |
1665 | } | |
1666 | ||
1667 | ||
1668 | ||
1669 | ||
1670 | /************************************************* | |
1671 | * Set up connection info for logging * | |
1672 | *************************************************/ | |
1673 | ||
1674 | /* This function is called when logging information about an SMTP connection. | |
1675 | It sets up appropriate source information, depending on the type of connection. | |
dac79d3e PH |
1676 | If sender_fullhost is NULL, we are at a very early stage of the connection; |
1677 | just use the IP address. | |
059ec3d9 PH |
1678 | |
1679 | Argument: none | |
1680 | Returns: a string describing the connection | |
1681 | */ | |
1682 | ||
1683 | uschar * | |
1684 | smtp_get_connection_info(void) | |
1685 | { | |
f5d25c2b JH |
1686 | const uschar * hostname = sender_fullhost |
1687 | ? sender_fullhost : sender_host_address; | |
dac79d3e | 1688 | |
059ec3d9 | 1689 | if (host_checking) |
dac79d3e | 1690 | return string_sprintf("SMTP connection from %s", hostname); |
059ec3d9 PH |
1691 | |
1692 | if (sender_host_unknown || sender_host_notsocket) | |
1693 | return string_sprintf("SMTP connection from %s", sender_ident); | |
1694 | ||
1695 | if (is_inetd) | |
dac79d3e | 1696 | return string_sprintf("SMTP connection from %s (via inetd)", hostname); |
059ec3d9 | 1697 | |
6c6d6e48 | 1698 | if (LOGGING(incoming_interface) && interface_address != NULL) |
dac79d3e | 1699 | return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname, |
059ec3d9 PH |
1700 | interface_address, interface_port); |
1701 | ||
dac79d3e | 1702 | return string_sprintf("SMTP connection from %s", hostname); |
059ec3d9 PH |
1703 | } |
1704 | ||
1705 | ||
1706 | ||
e45a1c37 | 1707 | #ifdef SUPPORT_TLS |
887291d2 JH |
1708 | /* Append TLS-related information to a log line |
1709 | ||
1710 | Arguments: | |
1711 | s String under construction: allocated string to extend, or NULL | |
1712 | sizep Pointer to current allocation size (update on return), or NULL | |
1713 | ptrp Pointer to index for new entries in string (update on return), or NULL | |
1714 | ||
1715 | Returns: Allocated string or NULL | |
1716 | */ | |
e45a1c37 JH |
1717 | static uschar * |
1718 | s_tlslog(uschar * s, int * sizep, int * ptrp) | |
1719 | { | |
1720 | int size = sizep ? *sizep : 0; | |
1721 | int ptr = ptrp ? *ptrp : 0; | |
1722 | ||
6c6d6e48 | 1723 | if (LOGGING(tls_cipher) && tls_in.cipher != NULL) |
e45a1c37 | 1724 | s = string_append(s, &size, &ptr, 2, US" X=", tls_in.cipher); |
6c6d6e48 | 1725 | if (LOGGING(tls_certificate_verified) && tls_in.cipher != NULL) |
e45a1c37 JH |
1726 | s = string_append(s, &size, &ptr, 2, US" CV=", |
1727 | tls_in.certificate_verified? "yes":"no"); | |
6c6d6e48 | 1728 | if (LOGGING(tls_peerdn) && tls_in.peerdn != NULL) |
e45a1c37 JH |
1729 | s = string_append(s, &size, &ptr, 3, US" DN=\"", |
1730 | string_printing(tls_in.peerdn), US"\""); | |
6c6d6e48 | 1731 | if (LOGGING(tls_sni) && tls_in.sni != NULL) |
e45a1c37 JH |
1732 | s = string_append(s, &size, &ptr, 3, US" SNI=\"", |
1733 | string_printing(tls_in.sni), US"\""); | |
1734 | ||
67d81c10 JH |
1735 | if (s) |
1736 | { | |
1737 | s[ptr] = '\0'; | |
1738 | if (sizep) *sizep = size; | |
1739 | if (ptrp) *ptrp = ptr; | |
1740 | } | |
e45a1c37 JH |
1741 | return s; |
1742 | } | |
1743 | #endif | |
1744 | ||
b4ed4da0 PH |
1745 | /************************************************* |
1746 | * Log lack of MAIL if so configured * | |
1747 | *************************************************/ | |
1748 | ||
1749 | /* This function is called when an SMTP session ends. If the log selector | |
1750 | smtp_no_mail is set, write a log line giving some details of what has happened | |
1751 | in the SMTP session. | |
1752 | ||
1753 | Arguments: none | |
1754 | Returns: nothing | |
1755 | */ | |
1756 | ||
1757 | void | |
1758 | smtp_log_no_mail(void) | |
1759 | { | |
1760 | int size, ptr, i; | |
1761 | uschar *s, *sep; | |
1762 | ||
6c6d6e48 | 1763 | if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail)) |
b4ed4da0 PH |
1764 | return; |
1765 | ||
1766 | s = NULL; | |
1767 | size = ptr = 0; | |
1768 | ||
1769 | if (sender_host_authenticated != NULL) | |
1770 | { | |
1771 | s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated); | |
1772 | if (authenticated_id != NULL) | |
1773 | s = string_append(s, &size, &ptr, 2, US":", authenticated_id); | |
1774 | } | |
1775 | ||
1776 | #ifdef SUPPORT_TLS | |
e45a1c37 | 1777 | s = s_tlslog(s, &size, &ptr); |
3f0945ff | 1778 | #endif |
b4ed4da0 PH |
1779 | |
1780 | sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)? | |
1781 | US" C=..." : US" C="; | |
1782 | for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++) | |
1783 | { | |
1784 | if (smtp_connection_had[i] != SCH_NONE) | |
1785 | { | |
1786 | s = string_append(s, &size, &ptr, 2, sep, | |
1787 | smtp_names[smtp_connection_had[i]]); | |
1788 | sep = US","; | |
1789 | } | |
1790 | } | |
1791 | ||
1792 | for (i = 0; i < smtp_ch_index; i++) | |
1793 | { | |
1794 | s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]); | |
1795 | sep = US","; | |
1796 | } | |
1797 | ||
1798 | if (s != NULL) s[ptr] = 0; else s = US""; | |
1799 | log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s", | |
1800 | host_and_ident(FALSE), | |
19050083 JH |
1801 | readconf_printtime( (int) ((long)time(NULL) - (long)smtp_connection_start)), |
1802 | s); | |
b4ed4da0 PH |
1803 | } |
1804 | ||
1805 | ||
1806 | ||
059ec3d9 PH |
1807 | /************************************************* |
1808 | * Check HELO line and set sender_helo_name * | |
1809 | *************************************************/ | |
1810 | ||
1811 | /* Check the format of a HELO line. The data for HELO/EHLO is supposed to be | |
1812 | the domain name of the sending host, or an ip literal in square brackets. The | |
4c04137d | 1813 | argument is placed in sender_helo_name, which is in malloc store, because it |
059ec3d9 PH |
1814 | must persist over multiple incoming messages. If helo_accept_junk is set, this |
1815 | host is permitted to send any old junk (needed for some broken hosts). | |
1816 | Otherwise, helo_allow_chars can be used for rogue characters in general | |
1817 | (typically people want to let in underscores). | |
1818 | ||
1819 | Argument: | |
1820 | s the data portion of the line (already past any white space) | |
1821 | ||
1822 | Returns: TRUE or FALSE | |
1823 | */ | |
1824 | ||
1825 | static BOOL | |
1826 | check_helo(uschar *s) | |
1827 | { | |
1828 | uschar *start = s; | |
1829 | uschar *end = s + Ustrlen(s); | |
1830 | BOOL yield = helo_accept_junk; | |
1831 | ||
1832 | /* Discard any previous helo name */ | |
1833 | ||
1834 | if (sender_helo_name != NULL) | |
1835 | { | |
1836 | store_free(sender_helo_name); | |
1837 | sender_helo_name = NULL; | |
1838 | } | |
1839 | ||
1840 | /* Skip tests if junk is permitted. */ | |
1841 | ||
1842 | if (!yield) | |
1843 | { | |
1844 | /* Allow the new standard form for IPv6 address literals, namely, | |
1845 | [IPv6:....], and because someone is bound to use it, allow an equivalent | |
1846 | IPv4 form. Allow plain addresses as well. */ | |
1847 | ||
1848 | if (*s == '[') | |
1849 | { | |
1850 | if (end[-1] == ']') | |
1851 | { | |
1852 | end[-1] = 0; | |
1853 | if (strncmpic(s, US"[IPv6:", 6) == 0) | |
1854 | yield = (string_is_ip_address(s+6, NULL) == 6); | |
1855 | else if (strncmpic(s, US"[IPv4:", 6) == 0) | |
1856 | yield = (string_is_ip_address(s+6, NULL) == 4); | |
1857 | else | |
1858 | yield = (string_is_ip_address(s+1, NULL) != 0); | |
1859 | end[-1] = ']'; | |
1860 | } | |
1861 | } | |
1862 | ||
1863 | /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars | |
1864 | that have been configured (usually underscore - sigh). */ | |
1865 | ||
1866 | else if (*s != 0) | |
1867 | { | |
1868 | yield = TRUE; | |
1869 | while (*s != 0) | |
1870 | { | |
1871 | if (!isalnum(*s) && *s != '.' && *s != '-' && | |
1872 | Ustrchr(helo_allow_chars, *s) == NULL) | |
1873 | { | |
1874 | yield = FALSE; | |
1875 | break; | |
1876 | } | |
1877 | s++; | |
1878 | } | |
1879 | } | |
1880 | } | |
1881 | ||
1882 | /* Save argument if OK */ | |
1883 | ||
1884 | if (yield) sender_helo_name = string_copy_malloc(start); | |
1885 | return yield; | |
1886 | } | |
1887 | ||
1888 | ||
1889 | ||
1890 | ||
1891 | ||
1892 | /************************************************* | |
1893 | * Extract SMTP command option * | |
1894 | *************************************************/ | |
1895 | ||
ca86f471 | 1896 | /* This function picks the next option setting off the end of smtp_cmd_data. It |
059ec3d9 PH |
1897 | is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP |
1898 | things that can appear there. | |
1899 | ||
1900 | Arguments: | |
1901 | name point this at the name | |
1902 | value point this at the data string | |
1903 | ||
1904 | Returns: TRUE if found an option | |
1905 | */ | |
1906 | ||
1907 | static BOOL | |
1908 | extract_option(uschar **name, uschar **value) | |
1909 | { | |
1910 | uschar *n; | |
ca86f471 | 1911 | uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1; |
059ec3d9 PH |
1912 | while (isspace(*v)) v--; |
1913 | v[1] = 0; | |
d7a2c833 JH |
1914 | while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) |
1915 | { | |
1916 | /* Take care to not stop at a space embedded in a quoted local-part */ | |
1917 | ||
1918 | if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1); | |
1919 | v--; | |
1920 | } | |
059ec3d9 PH |
1921 | |
1922 | n = v; | |
fd98a5c6 JH |
1923 | if (*v == '=') |
1924 | { | |
1925 | while(isalpha(n[-1])) n--; | |
1926 | /* RFC says SP, but TAB seen in wild and other major MTAs accept it */ | |
1927 | if (!isspace(n[-1])) return FALSE; | |
1928 | n[-1] = 0; | |
1929 | } | |
1930 | else | |
1931 | { | |
1932 | n++; | |
1933 | if (v == smtp_cmd_data) return FALSE; | |
1934 | } | |
059ec3d9 | 1935 | *v++ = 0; |
fd98a5c6 | 1936 | *name = n; |
059ec3d9 PH |
1937 | *value = v; |
1938 | return TRUE; | |
1939 | } | |
1940 | ||
1941 | ||
1942 | ||
1943 | ||
1944 | ||
059ec3d9 PH |
1945 | /************************************************* |
1946 | * Reset for new message * | |
1947 | *************************************************/ | |
1948 | ||
1949 | /* This function is called whenever the SMTP session is reset from | |
1950 | within either of the setup functions. | |
1951 | ||
1952 | Argument: the stacking pool storage reset point | |
1953 | Returns: nothing | |
1954 | */ | |
1955 | ||
1956 | static void | |
1957 | smtp_reset(void *reset_point) | |
1958 | { | |
059ec3d9 PH |
1959 | recipients_list = NULL; |
1960 | rcpt_count = rcpt_defer_count = rcpt_fail_count = | |
1961 | raw_recipients_count = recipients_count = recipients_list_max = 0; | |
2e0c1448 | 1962 | message_linecount = 0; |
059ec3d9 | 1963 | message_size = -1; |
71fafd95 | 1964 | acl_added_headers = NULL; |
e7568d51 | 1965 | acl_removed_headers = NULL; |
059ec3d9 | 1966 | queue_only_policy = FALSE; |
2679d413 PH |
1967 | rcpt_smtp_response = NULL; |
1968 | rcpt_smtp_response_same = TRUE; | |
1969 | rcpt_in_progress = FALSE; | |
69358f02 | 1970 | deliver_freeze = FALSE; /* Can be set by ACL */ |
6a3f1455 | 1971 | freeze_tell = freeze_tell_config; /* Can be set by ACL */ |
29aba418 | 1972 | fake_response = OK; /* Can be set by ACL */ |
6951ac6c | 1973 | #ifdef WITH_CONTENT_SCAN |
8523533c TK |
1974 | no_mbox_unspool = FALSE; /* Can be set by ACL */ |
1975 | #endif | |
69358f02 | 1976 | submission_mode = FALSE; /* Can be set by ACL */ |
f4ee74ac | 1977 | suppress_local_fixups = suppress_local_fixups_default; /* Can be set by ACL */ |
69358f02 PH |
1978 | active_local_from_check = local_from_check; /* Can be set by ACL */ |
1979 | active_local_sender_retain = local_sender_retain; /* Can be set by ACL */ | |
90341c71 JH |
1980 | sending_ip_address = NULL; |
1981 | return_path = sender_address = NULL; | |
1982 | sender_data = NULL; /* Can be set by ACL */ | |
1983 | deliver_localpart_orig = NULL; | |
1984 | deliver_domain_orig = NULL; | |
1985 | callout_address = NULL; | |
2fe1a124 | 1986 | submission_name = NULL; /* Can be set by ACL */ |
059ec3d9 PH |
1987 | raw_sender = NULL; /* After SMTP rewrite, before qualifying */ |
1988 | sender_address_unrewritten = NULL; /* Set only after verify rewrite */ | |
1989 | sender_verified_list = NULL; /* No senders verified */ | |
1990 | memset(sender_address_cache, 0, sizeof(sender_address_cache)); | |
1991 | memset(sender_domain_cache, 0, sizeof(sender_domain_cache)); | |
6c1c3d1d | 1992 | |
059ec3d9 | 1993 | authenticated_sender = NULL; |
8523533c TK |
1994 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
1995 | bmi_run = 0; | |
1996 | bmi_verdicts = NULL; | |
1997 | #endif | |
90341c71 | 1998 | dnslist_domain = dnslist_matched = NULL; |
80a47a2c | 1999 | #ifndef DISABLE_DKIM |
9e5d6b55 | 2000 | dkim_signers = NULL; |
80a47a2c TK |
2001 | dkim_disable_verify = FALSE; |
2002 | dkim_collect_input = FALSE; | |
f7572e5a | 2003 | #endif |
aa368db3 JH |
2004 | dsn_ret = 0; |
2005 | dsn_envid = NULL; | |
90341c71 | 2006 | deliver_host = deliver_host_address = NULL; /* Can be set by ACL */ |
aa368db3 JH |
2007 | #ifndef DISABLE_PRDR |
2008 | prdr_requested = FALSE; | |
2009 | #endif | |
8523533c TK |
2010 | #ifdef EXPERIMENTAL_SPF |
2011 | spf_header_comment = NULL; | |
2012 | spf_received = NULL; | |
8e669ac1 | 2013 | spf_result = NULL; |
8523533c TK |
2014 | spf_smtp_comment = NULL; |
2015 | #endif | |
8c5d388a | 2016 | #ifdef SUPPORT_I18N |
d1a13eea JH |
2017 | message_smtputf8 = FALSE; |
2018 | #endif | |
059ec3d9 PH |
2019 | body_linecount = body_zerocount = 0; |
2020 | ||
870f6ba8 TF |
2021 | sender_rate = sender_rate_limit = sender_rate_period = NULL; |
2022 | ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */ | |
2023 | /* Note that ratelimiters_conn persists across resets. */ | |
2024 | ||
38a0a95f | 2025 | /* Reset message ACL variables */ |
47ca6d6c | 2026 | |
38a0a95f | 2027 | acl_var_m = NULL; |
059ec3d9 PH |
2028 | |
2029 | /* The message body variables use malloc store. They may be set if this is | |
2030 | not the first message in an SMTP session and the previous message caused them | |
2031 | to be referenced in an ACL. */ | |
2032 | ||
90341c71 | 2033 | if (message_body) |
059ec3d9 PH |
2034 | { |
2035 | store_free(message_body); | |
2036 | message_body = NULL; | |
2037 | } | |
2038 | ||
90341c71 | 2039 | if (message_body_end) |
059ec3d9 PH |
2040 | { |
2041 | store_free(message_body_end); | |
2042 | message_body_end = NULL; | |
2043 | } | |
2044 | ||
2045 | /* Warning log messages are also saved in malloc store. They are saved to avoid | |
2046 | repetition in the same message, but it seems right to repeat them for different | |
4e88a19f | 2047 | messages. */ |
059ec3d9 | 2048 | |
90341c71 | 2049 | while (acl_warn_logged) |
059ec3d9 PH |
2050 | { |
2051 | string_item *this = acl_warn_logged; | |
2052 | acl_warn_logged = acl_warn_logged->next; | |
2053 | store_free(this); | |
2054 | } | |
90341c71 | 2055 | store_reset(reset_point); |
059ec3d9 PH |
2056 | } |
2057 | ||
2058 | ||
2059 | ||
2060 | ||
2061 | ||
2062 | /************************************************* | |
2063 | * Initialize for incoming batched SMTP message * | |
2064 | *************************************************/ | |
2065 | ||
2066 | /* This function is called from smtp_setup_msg() in the case when | |
2067 | smtp_batched_input is true. This happens when -bS is used to pass a whole batch | |
2068 | of messages in one file with SMTP commands between them. All errors must be | |
2069 | reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are | |
2070 | relevant. After an error on a sender, or an invalid recipient, the remainder | |
2071 | of the message is skipped. The value of received_protocol is already set. | |
2072 | ||
2073 | Argument: none | |
2074 | Returns: > 0 message successfully started (reached DATA) | |
2075 | = 0 QUIT read or end of file reached | |
2076 | < 0 should not occur | |
2077 | */ | |
2078 | ||
2079 | static int | |
2080 | smtp_setup_batch_msg(void) | |
2081 | { | |
2082 | int done = 0; | |
2083 | void *reset_point = store_get(0); | |
2084 | ||
2085 | /* Save the line count at the start of each transaction - single commands | |
2086 | like HELO and RSET count as whole transactions. */ | |
2087 | ||
2088 | bsmtp_transaction_linecount = receive_linecount; | |
2089 | ||
2090 | if ((receive_feof)()) return 0; /* Treat EOF as QUIT */ | |
2091 | ||
57cc2785 | 2092 | cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg"); |
059ec3d9 PH |
2093 | smtp_reset(reset_point); /* Reset for start of message */ |
2094 | ||
2095 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
2096 | value. The values are 2 larger than the required yield of the function. */ | |
2097 | ||
2098 | while (done <= 0) | |
2099 | { | |
2100 | uschar *errmess; | |
2101 | uschar *recipient = NULL; | |
2102 | int start, end, sender_domain, recipient_domain; | |
2103 | ||
bd8fbe36 | 2104 | switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) |
059ec3d9 PH |
2105 | { |
2106 | /* The HELO/EHLO commands set sender_address_helo if they have | |
2107 | valid data; otherwise they are ignored, except that they do | |
2108 | a reset of the state. */ | |
2109 | ||
2110 | case HELO_CMD: | |
2111 | case EHLO_CMD: | |
2112 | ||
ca86f471 | 2113 | check_helo(smtp_cmd_data); |
059ec3d9 PH |
2114 | /* Fall through */ |
2115 | ||
2116 | case RSET_CMD: | |
57cc2785 | 2117 | cancel_cutthrough_connection(TRUE, US"RSET received"); |
059ec3d9 PH |
2118 | smtp_reset(reset_point); |
2119 | bsmtp_transaction_linecount = receive_linecount; | |
2120 | break; | |
2121 | ||
2122 | ||
2123 | /* The MAIL FROM command requires an address as an operand. All we | |
2124 | do here is to parse it for syntactic correctness. The form "<>" is | |
2125 | a special case which converts into an empty string. The start/end | |
2126 | pointers in the original are not used further for this address, as | |
2127 | it is the canonical extracted address which is all that is kept. */ | |
2128 | ||
2129 | case MAIL_CMD: | |
474f71bf | 2130 | smtp_mailcmd_count++; /* Count for no-mail log */ |
059ec3d9 PH |
2131 | if (sender_address != NULL) |
2132 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2133 | moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given"); |
059ec3d9 | 2134 | |
ca86f471 | 2135 | if (smtp_cmd_data[0] == 0) |
059ec3d9 | 2136 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 2137 | moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand"); |
059ec3d9 PH |
2138 | |
2139 | /* Reset to start of message */ | |
2140 | ||
57cc2785 | 2141 | cancel_cutthrough_connection(TRUE, US"MAIL received"); |
059ec3d9 PH |
2142 | smtp_reset(reset_point); |
2143 | ||
2144 | /* Apply SMTP rewrite */ | |
2145 | ||
2146 | raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)? | |
ca86f471 PH |
2147 | rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE, |
2148 | US"", global_rewrite_rules) : smtp_cmd_data; | |
059ec3d9 PH |
2149 | |
2150 | /* Extract the address; the TRUE flag allows <> as valid */ | |
2151 | ||
2152 | raw_sender = | |
2153 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
2154 | TRUE); | |
2155 | ||
2156 | if (raw_sender == NULL) | |
2157 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2158 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); |
059ec3d9 PH |
2159 | |
2160 | sender_address = string_copy(raw_sender); | |
2161 | ||
2162 | /* Qualify unqualified sender addresses if permitted to do so. */ | |
2163 | ||
2164 | if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@') | |
2165 | { | |
2166 | if (allow_unqualified_sender) | |
2167 | { | |
2168 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
2169 | DEBUG(D_receive) debug_printf("unqualified address %s accepted " | |
2170 | "and rewritten\n", raw_sender); | |
2171 | } | |
2172 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2173 | else moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain " |
059ec3d9 PH |
2174 | "a domain"); |
2175 | } | |
2176 | break; | |
2177 | ||
2178 | ||
2179 | /* The RCPT TO command requires an address as an operand. All we do | |
2180 | here is to parse it for syntactic correctness. There may be any number | |
2181 | of RCPT TO commands, specifying multiple senders. We build them all into | |
2182 | a data structure that is in argc/argv format. The start/end values | |
2183 | given by parse_extract_address are not used, as we keep only the | |
2184 | extracted address. */ | |
2185 | ||
2186 | case RCPT_CMD: | |
2187 | if (sender_address == NULL) | |
2188 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2189 | moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given"); |
059ec3d9 | 2190 | |
ca86f471 | 2191 | if (smtp_cmd_data[0] == 0) |
059ec3d9 | 2192 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 2193 | moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand"); |
059ec3d9 PH |
2194 | |
2195 | /* Check maximum number allowed */ | |
2196 | ||
2197 | if (recipients_max > 0 && recipients_count + 1 > recipients_max) | |
2198 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2199 | moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients", |
059ec3d9 PH |
2200 | recipients_max_reject? "552": "452"); |
2201 | ||
2202 | /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a | |
2203 | recipient address */ | |
2204 | ||
2685d6e0 JH |
2205 | recipient = rewrite_existflags & rewrite_smtp |
2206 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
2207 | global_rewrite_rules) | |
2208 | : smtp_cmd_data; | |
059ec3d9 | 2209 | |
059ec3d9 PH |
2210 | recipient = parse_extract_address(recipient, &errmess, &start, &end, |
2211 | &recipient_domain, FALSE); | |
059ec3d9 | 2212 | |
2685d6e0 | 2213 | if (!recipient) |
059ec3d9 | 2214 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 2215 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); |
059ec3d9 PH |
2216 | |
2217 | /* If the recipient address is unqualified, qualify it if permitted. Then | |
2218 | add it to the list of recipients. */ | |
2219 | ||
2220 | if (recipient_domain == 0) | |
2221 | { | |
2222 | if (allow_unqualified_recipient) | |
2223 | { | |
2224 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
2225 | recipient); | |
2226 | recipient = rewrite_address_qualify(recipient, TRUE); | |
2227 | } | |
2228 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2229 | else moan_smtp_batch(smtp_cmd_buffer, "501 recipient address must contain " |
059ec3d9 PH |
2230 | "a domain"); |
2231 | } | |
2232 | receive_add_recipient(recipient, -1); | |
2233 | break; | |
2234 | ||
2235 | ||
2236 | /* The DATA command is legal only if it follows successful MAIL FROM | |
2237 | and RCPT TO commands. This function is complete when a valid DATA | |
2238 | command is encountered. */ | |
2239 | ||
2240 | case DATA_CMD: | |
2241 | if (sender_address == NULL || recipients_count <= 0) | |
2242 | { | |
2243 | /* The function moan_smtp_batch() does not return. */ | |
2244 | if (sender_address == NULL) | |
3ee512ff | 2245 | moan_smtp_batch(smtp_cmd_buffer, |
059ec3d9 PH |
2246 | "503 MAIL FROM:<sender> command must precede DATA"); |
2247 | else | |
3ee512ff | 2248 | moan_smtp_batch(smtp_cmd_buffer, |
059ec3d9 PH |
2249 | "503 RCPT TO:<recipient> must precede DATA"); |
2250 | } | |
2251 | else | |
2252 | { | |
2253 | done = 3; /* DATA successfully achieved */ | |
2254 | message_ended = END_NOTENDED; /* Indicate in middle of message */ | |
2255 | } | |
2256 | break; | |
2257 | ||
2258 | ||
2259 | /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */ | |
2260 | ||
2261 | case VRFY_CMD: | |
2262 | case EXPN_CMD: | |
2263 | case HELP_CMD: | |
2264 | case NOOP_CMD: | |
2265 | case ETRN_CMD: | |
2266 | bsmtp_transaction_linecount = receive_linecount; | |
2267 | break; | |
2268 | ||
2269 | ||
2270 | case EOF_CMD: | |
2271 | case QUIT_CMD: | |
2272 | done = 2; | |
2273 | break; | |
2274 | ||
2275 | ||
2276 | case BADARG_CMD: | |
2277 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2278 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data"); |
059ec3d9 PH |
2279 | break; |
2280 | ||
2281 | ||
2282 | case BADCHAR_CMD: | |
2283 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2284 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command"); |
059ec3d9 PH |
2285 | break; |
2286 | ||
2287 | ||
2288 | default: | |
2289 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 2290 | moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized"); |
059ec3d9 PH |
2291 | break; |
2292 | } | |
2293 | } | |
2294 | ||
2295 | return done - 2; /* Convert yield values */ | |
2296 | } | |
2297 | ||
2298 | ||
2299 | ||
2300 | ||
cf0c6164 JH |
2301 | static BOOL |
2302 | smtp_log_tls_fail(uschar * errstr) | |
2303 | { | |
2304 | uschar * conn_info = smtp_get_connection_info(); | |
2305 | ||
2306 | if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5; | |
2307 | /* I'd like to get separated H= here, but too hard for now */ | |
2308 | ||
2309 | log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr); | |
2310 | return FALSE; | |
2311 | } | |
2312 | ||
2313 | ||
059ec3d9 PH |
2314 | /************************************************* |
2315 | * Start an SMTP session * | |
2316 | *************************************************/ | |
2317 | ||
2318 | /* This function is called at the start of an SMTP session. Thereafter, | |
2319 | smtp_setup_msg() is called to initiate each separate message. This | |
2320 | function does host-specific testing, and outputs the banner line. | |
2321 | ||
2322 | Arguments: none | |
2323 | Returns: FALSE if the session can not continue; something has | |
2324 | gone wrong, or the connection to the host is blocked | |
2325 | */ | |
2326 | ||
2327 | BOOL | |
2328 | smtp_start_session(void) | |
2329 | { | |
2330 | int size = 256; | |
4e88a19f PH |
2331 | int ptr, esclen; |
2332 | uschar *user_msg, *log_msg; | |
2333 | uschar *code, *esc; | |
059ec3d9 PH |
2334 | uschar *p, *s, *ss; |
2335 | ||
b4ed4da0 PH |
2336 | smtp_connection_start = time(NULL); |
2337 | for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++) | |
2338 | smtp_connection_had[smtp_ch_index] = SCH_NONE; | |
2339 | smtp_ch_index = 0; | |
2340 | ||
00f00ca5 PH |
2341 | /* Default values for certain variables */ |
2342 | ||
059ec3d9 | 2343 | helo_seen = esmtp = helo_accept_junk = FALSE; |
b4ed4da0 | 2344 | smtp_mailcmd_count = 0; |
059ec3d9 PH |
2345 | count_nonmail = TRUE_UNSET; |
2346 | synprot_error_count = unknown_command_count = nonmail_command_count = 0; | |
2347 | smtp_delay_mail = smtp_rlm_base; | |
2348 | auth_advertised = FALSE; | |
2349 | pipelining_advertised = FALSE; | |
cf8b11a5 | 2350 | pipelining_enable = TRUE; |
059ec3d9 | 2351 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; |
8f128379 | 2352 | smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */ |
059ec3d9 | 2353 | |
33d73e3b PH |
2354 | /* If receiving by -bs from a trusted user, or testing with -bh, we allow |
2355 | authentication settings from -oMaa to remain in force. */ | |
2356 | ||
2357 | if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL; | |
059ec3d9 PH |
2358 | authenticated_by = NULL; |
2359 | ||
2360 | #ifdef SUPPORT_TLS | |
817d9f57 | 2361 | tls_in.cipher = tls_in.peerdn = NULL; |
9d1c15ef JH |
2362 | tls_in.ourcert = tls_in.peercert = NULL; |
2363 | tls_in.sni = NULL; | |
44662487 | 2364 | tls_in.ocsp = OCSP_NOT_REQ; |
059ec3d9 PH |
2365 | tls_advertised = FALSE; |
2366 | #endif | |
6c1c3d1d | 2367 | dsn_advertised = FALSE; |
8c5d388a | 2368 | #ifdef SUPPORT_I18N |
d1a13eea JH |
2369 | smtputf8_advertised = FALSE; |
2370 | #endif | |
059ec3d9 PH |
2371 | |
2372 | /* Reset ACL connection variables */ | |
2373 | ||
38a0a95f | 2374 | acl_var_c = NULL; |
059ec3d9 | 2375 | |
ca86f471 | 2376 | /* Allow for trailing 0 in the command and data buffers. */ |
3ee512ff | 2377 | |
bd8fbe36 | 2378 | if (!(smtp_cmd_buffer = US malloc(2*SMTP_CMD_BUFFER_SIZE + 2))) |
059ec3d9 PH |
2379 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
2380 | "malloc() failed for SMTP command buffer"); | |
40c90bca | 2381 | |
2416c261 | 2382 | smtp_cmd_buffer[0] = 0; |
bd8fbe36 | 2383 | smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1; |
059ec3d9 PH |
2384 | |
2385 | /* For batched input, the protocol setting can be overridden from the | |
2386 | command line by a trusted caller. */ | |
2387 | ||
2388 | if (smtp_batched_input) | |
2389 | { | |
40c90bca | 2390 | if (!received_protocol) received_protocol = US"local-bsmtp"; |
059ec3d9 PH |
2391 | } |
2392 | ||
2393 | /* For non-batched SMTP input, the protocol setting is forced here. It will be | |
2394 | reset later if any of EHLO/AUTH/STARTTLS are received. */ | |
2395 | ||
2396 | else | |
2397 | received_protocol = | |
e524074d | 2398 | (sender_host_address ? protocols : protocols_local) [pnormal]; |
059ec3d9 PH |
2399 | |
2400 | /* Set up the buffer for inputting using direct read() calls, and arrange to | |
2401 | call the local functions instead of the standard C ones. */ | |
2402 | ||
bd8fbe36 | 2403 | if (!(smtp_inbuffer = (uschar *)malloc(IN_BUFFER_SIZE))) |
059ec3d9 | 2404 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer"); |
40c90bca | 2405 | |
059ec3d9 | 2406 | receive_getc = smtp_getc; |
0d81dabc | 2407 | receive_getbuf = smtp_getbuf; |
584e96c6 | 2408 | receive_get_cache = smtp_get_cache; |
059ec3d9 PH |
2409 | receive_ungetc = smtp_ungetc; |
2410 | receive_feof = smtp_feof; | |
2411 | receive_ferror = smtp_ferror; | |
58eb016e | 2412 | receive_smtp_buffered = smtp_buffered; |
059ec3d9 PH |
2413 | smtp_inptr = smtp_inend = smtp_inbuffer; |
2414 | smtp_had_eof = smtp_had_error = 0; | |
2415 | ||
2416 | /* Set up the message size limit; this may be host-specific */ | |
2417 | ||
d45b1de8 PH |
2418 | thismessage_size_limit = expand_string_integer(message_size_limit, TRUE); |
2419 | if (expand_string_message != NULL) | |
059ec3d9 PH |
2420 | { |
2421 | if (thismessage_size_limit == -1) | |
2422 | log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: " | |
2423 | "%s", expand_string_message); | |
2424 | else | |
2425 | log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: " | |
2426 | "%s", expand_string_message); | |
2427 | smtp_closedown(US"Temporary local problem - please try later"); | |
2428 | return FALSE; | |
2429 | } | |
2430 | ||
2431 | /* When a message is input locally via the -bs or -bS options, sender_host_ | |
2432 | unknown is set unless -oMa was used to force an IP address, in which case it | |
2433 | is checked like a real remote connection. When -bs is used from inetd, this | |
2434 | flag is not set, causing the sending host to be checked. The code that deals | |
2435 | with IP source routing (if configured) is never required for -bs or -bS and | |
2436 | the flag sender_host_notsocket is used to suppress it. | |
2437 | ||
2438 | If smtp_accept_max and smtp_accept_reserve are set, keep some connections in | |
2439 | reserve for certain hosts and/or networks. */ | |
2440 | ||
2441 | if (!sender_host_unknown) | |
2442 | { | |
2443 | int rc; | |
2444 | BOOL reserved_host = FALSE; | |
2445 | ||
2446 | /* Look up IP options (source routing info) on the socket if this is not an | |
2447 | -oMa "host", and if any are found, log them and drop the connection. | |
2448 | ||
2449 | Linux (and others now, see below) is different to everyone else, so there | |
2450 | has to be some conditional compilation here. Versions of Linux before 2.1.15 | |
2451 | used a structure whose name was "options". Somebody finally realized that | |
2452 | this name was silly, and it got changed to "ip_options". I use the | |
2453 | newer name here, but there is a fudge in the script that sets up os.h | |
2454 | to define a macro in older Linux systems. | |
2455 | ||
2456 | Sigh. Linux is a fast-moving target. Another generation of Linux uses | |
2457 | glibc 2, which has chosen ip_opts for the structure name. This is now | |
2458 | really a glibc thing rather than a Linux thing, so the condition name | |
2459 | has been changed to reflect this. It is relevant also to GNU/Hurd. | |
2460 | ||
2461 | Mac OS 10.x (Darwin) is like the later glibc versions, but without the | |
2462 | setting of the __GLIBC__ macro, so we can't detect it automatically. There's | |
2463 | a special macro defined in the os.h file. | |
2464 | ||
2465 | Some DGUX versions on older hardware appear not to support IP options at | |
2466 | all, so there is now a general macro which can be set to cut out this | |
2467 | support altogether. | |
2468 | ||
2469 | How to do this properly in IPv6 is not yet known. */ | |
2470 | ||
2471 | #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS) | |
2472 | ||
2473 | #ifdef GLIBC_IP_OPTIONS | |
2474 | #if (!defined __GLIBC__) || (__GLIBC__ < 2) | |
2475 | #define OPTSTYLE 1 | |
2476 | #else | |
2477 | #define OPTSTYLE 2 | |
2478 | #endif | |
2479 | #elif defined DARWIN_IP_OPTIONS | |
2480 | #define OPTSTYLE 2 | |
2481 | #else | |
2482 | #define OPTSTYLE 3 | |
2483 | #endif | |
2484 | ||
2485 | if (!host_checking && !sender_host_notsocket) | |
2486 | { | |
2487 | #if OPTSTYLE == 1 | |
36a3b041 | 2488 | EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN; |
059ec3d9 PH |
2489 | struct ip_options *ipopt = store_get(optlen); |
2490 | #elif OPTSTYLE == 2 | |
2491 | struct ip_opts ipoptblock; | |
2492 | struct ip_opts *ipopt = &ipoptblock; | |
36a3b041 | 2493 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); |
059ec3d9 PH |
2494 | #else |
2495 | struct ipoption ipoptblock; | |
2496 | struct ipoption *ipopt = &ipoptblock; | |
36a3b041 | 2497 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); |
059ec3d9 PH |
2498 | #endif |
2499 | ||
2500 | /* Occasional genuine failures of getsockopt() have been seen - for | |
2501 | example, "reset by peer". Therefore, just log and give up on this | |
2502 | call, unless the error is ENOPROTOOPT. This error is given by systems | |
2503 | that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time | |
2504 | of writing. So for that error, carry on - we just can't do an IP options | |
2505 | check. */ | |
2506 | ||
2507 | DEBUG(D_receive) debug_printf("checking for IP options\n"); | |
2508 | ||
2509 | if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt), | |
2510 | &optlen) < 0) | |
2511 | { | |
2512 | if (errno != ENOPROTOOPT) | |
2513 | { | |
2514 | log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s", | |
2515 | host_and_ident(FALSE), strerror(errno)); | |
925ac8e4 | 2516 | smtp_printf("451 SMTP service not available\r\n", FALSE); |
059ec3d9 PH |
2517 | return FALSE; |
2518 | } | |
2519 | } | |
2520 | ||
2521 | /* Deal with any IP options that are set. On the systems I have looked at, | |
2522 | the value of MAX_IPOPTLEN has been 40, meaning that there should never be | |
2523 | more logging data than will fit in big_buffer. Nevertheless, after somebody | |
2524 | questioned this code, I've added in some paranoid checking. */ | |
2525 | ||
2526 | else if (optlen > 0) | |
2527 | { | |
2528 | uschar *p = big_buffer; | |
2529 | uschar *pend = big_buffer + big_buffer_size; | |
2530 | uschar *opt, *adptr; | |
2531 | int optcount; | |
2532 | struct in_addr addr; | |
2533 | ||
2534 | #if OPTSTYLE == 1 | |
2535 | uschar *optstart = (uschar *)(ipopt->__data); | |
2536 | #elif OPTSTYLE == 2 | |
2537 | uschar *optstart = (uschar *)(ipopt->ip_opts); | |
2538 | #else | |
2539 | uschar *optstart = (uschar *)(ipopt->ipopt_list); | |
2540 | #endif | |
2541 | ||
2542 | DEBUG(D_receive) debug_printf("IP options exist\n"); | |
2543 | ||
2544 | Ustrcpy(p, "IP options on incoming call:"); | |
2545 | p += Ustrlen(p); | |
2546 | ||
2547 | for (opt = optstart; opt != NULL && | |
2548 | opt < (uschar *)(ipopt) + optlen;) | |
2549 | { | |
2550 | switch (*opt) | |
2551 | { | |
2552 | case IPOPT_EOL: | |
2553 | opt = NULL; | |
2554 | break; | |
2555 | ||
2556 | case IPOPT_NOP: | |
2557 | opt++; | |
2558 | break; | |
2559 | ||
2560 | case IPOPT_SSRR: | |
2561 | case IPOPT_LSRR: | |
2562 | if (!string_format(p, pend-p, " %s [@%s", | |
2563 | (*opt == IPOPT_SSRR)? "SSRR" : "LSRR", | |
2564 | #if OPTSTYLE == 1 | |
2565 | inet_ntoa(*((struct in_addr *)(&(ipopt->faddr)))))) | |
2566 | #elif OPTSTYLE == 2 | |
2567 | inet_ntoa(ipopt->ip_dst))) | |
2568 | #else | |
2569 | inet_ntoa(ipopt->ipopt_dst))) | |
2570 | #endif | |
2571 | { | |
2572 | opt = NULL; | |
2573 | break; | |
2574 | } | |
2575 | ||
2576 | p += Ustrlen(p); | |
2577 | optcount = (opt[1] - 3) / sizeof(struct in_addr); | |
2578 | adptr = opt + 3; | |
2579 | while (optcount-- > 0) | |
2580 | { | |
2581 | memcpy(&addr, adptr, sizeof(addr)); | |
2582 | if (!string_format(p, pend - p - 1, "%s%s", | |
2583 | (optcount == 0)? ":" : "@", inet_ntoa(addr))) | |
2584 | { | |
2585 | opt = NULL; | |
2586 | break; | |
2587 | } | |
2588 | p += Ustrlen(p); | |
2589 | adptr += sizeof(struct in_addr); | |
2590 | } | |
2591 | *p++ = ']'; | |
2592 | opt += opt[1]; | |
2593 | break; | |
2594 | ||
2595 | default: | |
2596 | { | |
2597 | int i; | |
2598 | if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; } | |
2599 | Ustrcat(p, "[ "); | |
2600 | p += 2; | |
2601 | for (i = 0; i < opt[1]; i++) | |
2602 | { | |
2603 | sprintf(CS p, "%2.2x ", opt[i]); | |
2604 | p += 3; | |
2605 | } | |
2606 | *p++ = ']'; | |
2607 | } | |
2608 | opt += opt[1]; | |
2609 | break; | |
2610 | } | |
2611 | } | |
2612 | ||
2613 | *p = 0; | |
2614 | log_write(0, LOG_MAIN, "%s", big_buffer); | |
2615 | ||
2616 | /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */ | |
2617 | ||
2618 | log_write(0, LOG_MAIN|LOG_REJECT, | |
2619 | "connection from %s refused (IP options)", host_and_ident(FALSE)); | |
2620 | ||
925ac8e4 | 2621 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
059ec3d9 PH |
2622 | return FALSE; |
2623 | } | |
2624 | ||
2625 | /* Length of options = 0 => there are no options */ | |
2626 | ||
2627 | else DEBUG(D_receive) debug_printf("no IP options found\n"); | |
2628 | } | |
2629 | #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */ | |
2630 | ||
2631 | /* Set keep-alive in socket options. The option is on by default. This | |
2632 | setting is an attempt to get rid of some hanging connections that stick in | |
2633 | read() when the remote end (usually a dialup) goes away. */ | |
2634 | ||
2635 | if (smtp_accept_keepalive && !sender_host_notsocket) | |
2636 | ip_keepalive(fileno(smtp_out), sender_host_address, FALSE); | |
2637 | ||
2638 | /* If the current host matches host_lookup, set the name by doing a | |
2639 | reverse lookup. On failure, sender_host_name will be NULL and | |
2640 | host_lookup_failed will be TRUE. This may or may not be serious - optional | |
2641 | checks later. */ | |
2642 | ||
2643 | if (verify_check_host(&host_lookup) == OK) | |
2644 | { | |
2645 | (void)host_name_lookup(); | |
2646 | host_build_sender_fullhost(); | |
2647 | } | |
2648 | ||
2649 | /* Delay this until we have the full name, if it is looked up. */ | |
2650 | ||
2651 | set_process_info("handling incoming connection from %s", | |
2652 | host_and_ident(FALSE)); | |
2653 | ||
1ad6489e JH |
2654 | /* Expand smtp_receive_timeout, if needed */ |
2655 | ||
2656 | if (smtp_receive_timeout_s) | |
2657 | { | |
2658 | uschar * exp; | |
2659 | if ( !(exp = expand_string(smtp_receive_timeout_s)) | |
2660 | || !(*exp) | |
2661 | || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0 | |
2662 | ) | |
2663 | log_write(0, LOG_MAIN|LOG_PANIC, | |
2664 | "bad value for smtp_receive_timeout: '%s'", exp ? exp : US""); | |
2665 | } | |
2666 | ||
059ec3d9 PH |
2667 | /* Test for explicit connection rejection */ |
2668 | ||
2669 | if (verify_check_host(&host_reject_connection) == OK) | |
2670 | { | |
2671 | log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection " | |
2672 | "from %s (host_reject_connection)", host_and_ident(FALSE)); | |
925ac8e4 | 2673 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
059ec3d9 PH |
2674 | return FALSE; |
2675 | } | |
2676 | ||
afb3eaaf PH |
2677 | /* Test with TCP Wrappers if so configured. There is a problem in that |
2678 | hosts_ctl() returns 0 (deny) under a number of system failure circumstances, | |
2679 | such as disks dying. In these cases, it is desirable to reject with a 4xx | |
2680 | error instead of a 5xx error. There isn't a "right" way to detect such | |
2681 | problems. The following kludge is used: errno is zeroed before calling | |
2682 | hosts_ctl(). If the result is "reject", a 5xx error is given only if the | |
2683 | value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does | |
2684 | not exist). */ | |
059ec3d9 | 2685 | |
1811cb4c | 2686 | #ifdef USE_TCP_WRAPPERS |
afb3eaaf | 2687 | errno = 0; |
1811cb4c | 2688 | if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name))) |
5dc43717 JJ |
2689 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" " |
2690 | "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name), | |
2691 | expand_string_message); | |
1811cb4c | 2692 | |
5dc43717 | 2693 | if (!hosts_ctl(tcp_wrappers_name, |
1811cb4c JH |
2694 | sender_host_name ? CS sender_host_name : STRING_UNKNOWN, |
2695 | sender_host_address ? CS sender_host_address : STRING_UNKNOWN, | |
2696 | sender_ident ? CS sender_ident : STRING_UNKNOWN)) | |
059ec3d9 | 2697 | { |
afb3eaaf PH |
2698 | if (errno == 0 || errno == ENOENT) |
2699 | { | |
2700 | HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n"); | |
2701 | log_write(L_connection_reject, | |
2702 | LOG_MAIN|LOG_REJECT, "refused connection from %s " | |
2703 | "(tcp wrappers)", host_and_ident(FALSE)); | |
925ac8e4 | 2704 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
afb3eaaf PH |
2705 | } |
2706 | else | |
2707 | { | |
2708 | int save_errno = errno; | |
2709 | HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected " | |
2710 | "errno value %d\n", save_errno); | |
2711 | log_write(L_connection_reject, | |
2712 | LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s " | |
2713 | "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno); | |
925ac8e4 | 2714 | smtp_printf("451 Temporary local problem - please try later\r\n", FALSE); |
afb3eaaf | 2715 | } |
059ec3d9 PH |
2716 | return FALSE; |
2717 | } | |
1811cb4c | 2718 | #endif |
059ec3d9 | 2719 | |
b01dd148 PH |
2720 | /* Check for reserved slots. The value of smtp_accept_count has already been |
2721 | incremented to include this process. */ | |
059ec3d9 PH |
2722 | |
2723 | if (smtp_accept_max > 0 && | |
b01dd148 | 2724 | smtp_accept_count > smtp_accept_max - smtp_accept_reserve) |
059ec3d9 PH |
2725 | { |
2726 | if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK) | |
2727 | { | |
2728 | log_write(L_connection_reject, | |
2729 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2730 | "reserve list: connected=%d max=%d reserve=%d%s", | |
b01dd148 | 2731 | host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max, |
059ec3d9 PH |
2732 | smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : ""); |
2733 | smtp_printf("421 %s: Too many concurrent SMTP connections; " | |
925ac8e4 | 2734 | "please try again later\r\n", FALSE, smtp_active_hostname); |
059ec3d9 PH |
2735 | return FALSE; |
2736 | } | |
2737 | reserved_host = TRUE; | |
2738 | } | |
2739 | ||
2740 | /* If a load level above which only messages from reserved hosts are | |
2741 | accepted is set, check the load. For incoming calls via the daemon, the | |
2742 | check is done in the superior process if there are no reserved hosts, to | |
2743 | save a fork. In all cases, the load average will already be available | |
2744 | in a global variable at this point. */ | |
2745 | ||
2746 | if (smtp_load_reserve >= 0 && | |
2747 | load_average > smtp_load_reserve && | |
2748 | !reserved_host && | |
2749 | verify_check_host(&smtp_reserve_hosts) != OK) | |
2750 | { | |
2751 | log_write(L_connection_reject, | |
2752 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2753 | "reserve list and load average = %.2f", host_and_ident(FALSE), | |
2754 | (double)load_average/1000.0); | |
925ac8e4 | 2755 | smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE, |
059ec3d9 PH |
2756 | smtp_active_hostname); |
2757 | return FALSE; | |
2758 | } | |
2759 | ||
2760 | /* Determine whether unqualified senders or recipients are permitted | |
2761 | for this host. Unfortunately, we have to do this every time, in order to | |
2762 | set the flags so that they can be inspected when considering qualifying | |
2763 | addresses in the headers. For a site that permits no qualification, this | |
2764 | won't take long, however. */ | |
2765 | ||
2766 | allow_unqualified_sender = | |
2767 | verify_check_host(&sender_unqualified_hosts) == OK; | |
2768 | ||
2769 | allow_unqualified_recipient = | |
2770 | verify_check_host(&recipient_unqualified_hosts) == OK; | |
2771 | ||
2772 | /* Determine whether HELO/EHLO is required for this host. The requirement | |
2773 | can be hard or soft. */ | |
2774 | ||
2775 | helo_required = verify_check_host(&helo_verify_hosts) == OK; | |
2776 | if (!helo_required) | |
2777 | helo_verify = verify_check_host(&helo_try_verify_hosts) == OK; | |
2778 | ||
2779 | /* Determine whether this hosts is permitted to send syntactic junk | |
2780 | after a HELO or EHLO command. */ | |
2781 | ||
2782 | helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK; | |
2783 | } | |
2784 | ||
2785 | /* For batch SMTP input we are now done. */ | |
2786 | ||
2787 | if (smtp_batched_input) return TRUE; | |
2788 | ||
a3c86431 TL |
2789 | /* If valid Proxy Protocol source is connecting, set up session. |
2790 | * Failure will not allow any SMTP function other than QUIT. */ | |
1811cb4c JH |
2791 | |
2792 | #ifdef SUPPORT_PROXY | |
a3c86431 TL |
2793 | proxy_session = FALSE; |
2794 | proxy_session_failed = FALSE; | |
2795 | if (check_proxy_protocol_host()) | |
1811cb4c JH |
2796 | setup_proxy_protocol_host(); |
2797 | #endif | |
2798 | ||
2799 | /* Start up TLS if tls_on_connect is set. This is for supporting the legacy | |
2800 | smtps port for use with older style SSL MTAs. */ | |
2801 | ||
2802 | #ifdef SUPPORT_TLS | |
cf0c6164 JH |
2803 | if (tls_in.on_connect && tls_server_start(tls_require_ciphers, &user_msg) != OK) |
2804 | return smtp_log_tls_fail(user_msg); | |
a3c86431 TL |
2805 | #endif |
2806 | ||
1811cb4c | 2807 | /* Run the connect ACL if it exists */ |
059ec3d9 | 2808 | |
4e88a19f | 2809 | user_msg = NULL; |
3cc3f762 | 2810 | if (acl_smtp_connect) |
059ec3d9 PH |
2811 | { |
2812 | int rc; | |
3cc3f762 JH |
2813 | if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg, |
2814 | &log_msg)) != OK) | |
059ec3d9 | 2815 | { |
3cc3f762 | 2816 | (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg); |
059ec3d9 PH |
2817 | return FALSE; |
2818 | } | |
2819 | } | |
2820 | ||
2821 | /* Output the initial message for a two-way SMTP connection. It may contain | |
2822 | newlines, which then cause a multi-line response to be given. */ | |
2823 | ||
4e88a19f PH |
2824 | code = US"220"; /* Default status code */ |
2825 | esc = US""; /* Default extended status code */ | |
2826 | esclen = 0; /* Length of esc */ | |
2827 | ||
d4ff61d1 | 2828 | if (!user_msg) |
4e88a19f | 2829 | { |
d4ff61d1 | 2830 | if (!(s = expand_string(smtp_banner))) |
4e88a19f PH |
2831 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) " |
2832 | "failed: %s", smtp_banner, expand_string_message); | |
2833 | } | |
2834 | else | |
2835 | { | |
2836 | int codelen = 3; | |
2837 | s = user_msg; | |
4f6ae5c3 | 2838 | smtp_message_code(&code, &codelen, &s, NULL, TRUE); |
d6a96edc | 2839 | if (codelen > 4) |
4e88a19f PH |
2840 | { |
2841 | esc = code + 4; | |
2842 | esclen = codelen - 4; | |
2843 | } | |
2844 | } | |
059ec3d9 PH |
2845 | |
2846 | /* Remove any terminating newlines; might as well remove trailing space too */ | |
2847 | ||
2848 | p = s + Ustrlen(s); | |
2849 | while (p > s && isspace(p[-1])) p--; | |
2850 | *p = 0; | |
2851 | ||
2852 | /* It seems that CC:Mail is braindead, and assumes that the greeting message | |
2853 | is all contained in a single IP packet. The original code wrote out the | |
2854 | greeting using several calls to fprint/fputc, and on busy servers this could | |
2855 | cause it to be split over more than one packet - which caused CC:Mail to fall | |
2856 | over when it got the second part of the greeting after sending its first | |
2857 | command. Sigh. To try to avoid this, build the complete greeting message | |
2858 | first, and output it in one fell swoop. This gives a better chance of it | |
2859 | ending up as a single packet. */ | |
2860 | ||
2861 | ss = store_get(size); | |
2862 | ptr = 0; | |
2863 | ||
2864 | p = s; | |
2865 | do /* At least once, in case we have an empty string */ | |
2866 | { | |
2867 | int len; | |
2868 | uschar *linebreak = Ustrchr(p, '\n'); | |
c2f669a4 | 2869 | ss = string_catn(ss, &size, &ptr, code, 3); |
059ec3d9 PH |
2870 | if (linebreak == NULL) |
2871 | { | |
2872 | len = Ustrlen(p); | |
c2f669a4 | 2873 | ss = string_catn(ss, &size, &ptr, US" ", 1); |
059ec3d9 PH |
2874 | } |
2875 | else | |
2876 | { | |
2877 | len = linebreak - p; | |
c2f669a4 | 2878 | ss = string_catn(ss, &size, &ptr, US"-", 1); |
059ec3d9 | 2879 | } |
c2f669a4 JH |
2880 | ss = string_catn(ss, &size, &ptr, esc, esclen); |
2881 | ss = string_catn(ss, &size, &ptr, p, len); | |
2882 | ss = string_catn(ss, &size, &ptr, US"\r\n", 2); | |
059ec3d9 PH |
2883 | p += len; |
2884 | if (linebreak != NULL) p++; | |
2885 | } | |
2886 | while (*p != 0); | |
2887 | ||
2888 | ss[ptr] = 0; /* string_cat leaves room for this */ | |
2889 | ||
2890 | /* Before we write the banner, check that there is no input pending, unless | |
2891 | this synchronisation check is disabled. */ | |
2892 | ||
a14e5636 | 2893 | if (!check_sync()) |
059ec3d9 | 2894 | { |
40525d07 JH |
2895 | unsigned n = smtp_inend - smtp_inptr; |
2896 | if (n > 32) n = 32; | |
2897 | ||
a14e5636 PH |
2898 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol " |
2899 | "synchronization error (input sent without waiting for greeting): " | |
2900 | "rejected connection from %s input=\"%s\"", host_and_ident(TRUE), | |
40525d07 | 2901 | string_printing(string_copyn(smtp_inptr, n))); |
925ac8e4 | 2902 | smtp_printf("554 SMTP synchronization error\r\n", FALSE); |
a14e5636 | 2903 | return FALSE; |
059ec3d9 PH |
2904 | } |
2905 | ||
2906 | /* Now output the banner */ | |
2907 | ||
925ac8e4 | 2908 | smtp_printf("%s", FALSE, ss); |
059ec3d9 PH |
2909 | return TRUE; |
2910 | } | |
2911 | ||
2912 | ||
2913 | ||
2914 | ||
2915 | ||
2916 | /************************************************* | |
2917 | * Handle SMTP syntax and protocol errors * | |
2918 | *************************************************/ | |
2919 | ||
2920 | /* Write to the log for SMTP syntax errors in incoming commands, if configured | |
2921 | to do so. Then transmit the error response. The return value depends on the | |
2922 | number of syntax and protocol errors in this SMTP session. | |
2923 | ||
2924 | Arguments: | |
2925 | type error type, given as a log flag bit | |
2926 | code response code; <= 0 means don't send a response | |
2927 | data data to reflect in the response (can be NULL) | |
2928 | errmess the error message | |
2929 | ||
2930 | Returns: -1 limit of syntax/protocol errors NOT exceeded | |
2931 | +1 limit of syntax/protocol errors IS exceeded | |
2932 | ||
2933 | These values fit in with the values of the "done" variable in the main | |
2934 | processing loop in smtp_setup_msg(). */ | |
2935 | ||
2936 | static int | |
2937 | synprot_error(int type, int code, uschar *data, uschar *errmess) | |
2938 | { | |
2939 | int yield = -1; | |
2940 | ||
2941 | log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s", | |
2942 | (type == L_smtp_syntax_error)? "syntax" : "protocol", | |
3ee512ff | 2943 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess); |
059ec3d9 PH |
2944 | |
2945 | if (++synprot_error_count > smtp_max_synprot_errors) | |
2946 | { | |
2947 | yield = 1; | |
2948 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
2949 | "syntax or protocol errors (last command was \"%s\")", | |
0ebc4d69 | 2950 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
2951 | } |
2952 | ||
2953 | if (code > 0) | |
2954 | { | |
925ac8e4 JH |
2955 | smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ', |
2956 | data ? data : US"", data ? US": " : US"", errmess); | |
059ec3d9 | 2957 | if (yield == 1) |
925ac8e4 | 2958 | smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code); |
059ec3d9 PH |
2959 | } |
2960 | ||
2961 | return yield; | |
2962 | } | |
2963 | ||
2964 | ||
2965 | ||
2966 | ||
059ec3d9 PH |
2967 | /************************************************* |
2968 | * Send SMTP response, possibly multiline * | |
2969 | *************************************************/ | |
2970 | ||
2971 | /* There are, it seems, broken clients out there that cannot handle multiline | |
2972 | responses. If no_multiline_responses is TRUE (it can be set from an ACL), we | |
2973 | output nothing for non-final calls, and only the first line for anything else. | |
2974 | ||
2975 | Arguments: | |
a5bd321b | 2976 | code SMTP code, may involve extended status codes |
d6a96edc | 2977 | codelen length of smtp code; if > 4 there's an ESC |
059ec3d9 PH |
2978 | final FALSE if the last line isn't the final line |
2979 | msg message text, possibly containing newlines | |
2980 | ||
2981 | Returns: nothing | |
2982 | */ | |
2983 | ||
2984 | void | |
a5bd321b | 2985 | smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg) |
059ec3d9 | 2986 | { |
a5bd321b PH |
2987 | int esclen = 0; |
2988 | uschar *esc = US""; | |
2989 | ||
059ec3d9 PH |
2990 | if (!final && no_multiline_responses) return; |
2991 | ||
d6a96edc | 2992 | if (codelen > 4) |
a5bd321b PH |
2993 | { |
2994 | esc = code + 4; | |
2995 | esclen = codelen - 4; | |
2996 | } | |
2997 | ||
2679d413 PH |
2998 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs |
2999 | have had the same. Note: this code is also present in smtp_printf(). It would | |
3000 | be tidier to have it only in one place, but when it was added, it was easier to | |
3001 | do it that way, so as not to have to mess with the code for the RCPT command, | |
3002 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
3003 | ||
3004 | if (rcpt_in_progress) | |
3005 | { | |
3006 | if (rcpt_smtp_response == NULL) | |
3007 | rcpt_smtp_response = string_copy(msg); | |
3008 | else if (rcpt_smtp_response_same && | |
3009 | Ustrcmp(rcpt_smtp_response, msg) != 0) | |
3010 | rcpt_smtp_response_same = FALSE; | |
3011 | rcpt_in_progress = FALSE; | |
3012 | } | |
3013 | ||
925ac8e4 JH |
3014 | /* Not output the message, splitting it up into multiple lines if necessary. |
3015 | We only handle pipelining these responses as far as nonfinal/final groups, | |
3016 | not the whole MAIL/RCPT/DATA response set. */ | |
2679d413 | 3017 | |
059ec3d9 PH |
3018 | for (;;) |
3019 | { | |
3020 | uschar *nl = Ustrchr(msg, '\n'); | |
3021 | if (nl == NULL) | |
3022 | { | |
925ac8e4 | 3023 | smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg); |
059ec3d9 PH |
3024 | return; |
3025 | } | |
3026 | else if (nl[1] == 0 || no_multiline_responses) | |
3027 | { | |
925ac8e4 | 3028 | smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc, |
a5bd321b | 3029 | (int)(nl - msg), msg); |
059ec3d9 PH |
3030 | return; |
3031 | } | |
3032 | else | |
3033 | { | |
925ac8e4 | 3034 | smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg); |
059ec3d9 PH |
3035 | msg = nl + 1; |
3036 | while (isspace(*msg)) msg++; | |
3037 | } | |
3038 | } | |
3039 | } | |
3040 | ||
3041 | ||
3042 | ||
3043 | ||
4e88a19f PH |
3044 | /************************************************* |
3045 | * Parse user SMTP message * | |
3046 | *************************************************/ | |
3047 | ||
3048 | /* This function allows for user messages overriding the response code details | |
3049 | by providing a suitable response code string at the start of the message | |
3050 | user_msg. Check the message for starting with a response code and optionally an | |
3051 | extended status code. If found, check that the first digit is valid, and if so, | |
3052 | change the code pointer and length to use the replacement. An invalid code | |
3053 | causes a panic log; in this case, if the log messages is the same as the user | |
3054 | message, we must also adjust the value of the log message to show the code that | |
3055 | is actually going to be used (the original one). | |
3056 | ||
3057 | This function is global because it is called from receive.c as well as within | |
3058 | this module. | |
3059 | ||
d6a96edc PH |
3060 | Note that the code length returned includes the terminating whitespace |
3061 | character, which is always included in the regex match. | |
3062 | ||
4e88a19f PH |
3063 | Arguments: |
3064 | code SMTP code, may involve extended status codes | |
d6a96edc | 3065 | codelen length of smtp code; if > 4 there's an ESC |
4e88a19f PH |
3066 | msg message text |
3067 | log_msg optional log message, to be adjusted with the new SMTP code | |
4f6ae5c3 | 3068 | check_valid if true, verify the response code |
4e88a19f PH |
3069 | |
3070 | Returns: nothing | |
3071 | */ | |
3072 | ||
3073 | void | |
4f6ae5c3 JH |
3074 | smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg, |
3075 | BOOL check_valid) | |
4e88a19f PH |
3076 | { |
3077 | int n; | |
3078 | int ovector[3]; | |
3079 | ||
4f6ae5c3 | 3080 | if (!msg || !*msg) return; |
4e88a19f | 3081 | |
4f6ae5c3 JH |
3082 | if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0, |
3083 | PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return; | |
4e88a19f | 3084 | |
4f6ae5c3 | 3085 | if (check_valid && (*msg)[0] != (*code)[0]) |
4e88a19f PH |
3086 | { |
3087 | log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with " | |
3088 | "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg); | |
3089 | if (log_msg != NULL && *log_msg == *msg) | |
3090 | *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]); | |
3091 | } | |
3092 | else | |
3093 | { | |
3094 | *code = *msg; | |
3095 | *codelen = ovector[1]; /* Includes final space */ | |
3096 | } | |
3097 | *msg += ovector[1]; /* Chop the code off the message */ | |
3098 | return; | |
3099 | } | |
3100 | ||
3101 | ||
3102 | ||
3103 | ||
059ec3d9 PH |
3104 | /************************************************* |
3105 | * Handle an ACL failure * | |
3106 | *************************************************/ | |
3107 | ||
3108 | /* This function is called when acl_check() fails. As well as calls from within | |
3109 | this module, it is called from receive.c for an ACL after DATA. It sorts out | |
3110 | logging the incident, and sets up the error response. A message containing | |
3111 | newlines is turned into a multiline SMTP response, but for logging, only the | |
3112 | first line is used. | |
3113 | ||
a5bd321b PH |
3114 | There's a table of default permanent failure response codes to use in |
3115 | globals.c, along with the table of names. VFRY is special. Despite RFC1123 it | |
3116 | defaults disabled in Exim. However, discussion in connection with RFC 821bis | |
3117 | (aka RFC 2821) has concluded that the response should be 252 in the disabled | |
3118 | state, because there are broken clients that try VRFY before RCPT. A 5xx | |
3119 | response should be given only when the address is positively known to be | |
4f6ae5c3 JH |
3120 | undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides |
3121 | no explicit code, but if there is one we let it know best. | |
3122 | Also, for ETRN, 458 is given on refusal, and for AUTH, 503. | |
a5bd321b PH |
3123 | |
3124 | From Exim 4.63, it is possible to override the response code details by | |
3125 | providing a suitable response code string at the start of the message provided | |
3126 | in user_msg. The code's first digit is checked for validity. | |
059ec3d9 PH |
3127 | |
3128 | Arguments: | |
4f6ae5c3 JH |
3129 | where where the ACL was called from |
3130 | rc the failure code | |
3131 | user_msg a message that can be included in an SMTP response | |
3132 | log_msg a message for logging | |
059ec3d9 PH |
3133 | |
3134 | Returns: 0 in most cases | |
3135 | 2 if the failure code was FAIL_DROP, in which case the | |
3136 | SMTP connection should be dropped (this value fits with the | |
3137 | "done" variable in smtp_setup_msg() below) | |
3138 | */ | |
3139 | ||
3140 | int | |
3141 | smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg) | |
3142 | { | |
059ec3d9 | 3143 | BOOL drop = rc == FAIL_DROP; |
a5bd321b | 3144 | int codelen = 3; |
a5bd321b | 3145 | uschar *smtp_code; |
059ec3d9 PH |
3146 | uschar *lognl; |
3147 | uschar *sender_info = US""; | |
64ffc24f | 3148 | uschar *what = |
8523533c | 3149 | #ifdef WITH_CONTENT_SCAN |
3cc3f762 | 3150 | where == ACL_WHERE_MIME ? US"during MIME ACL checks" : |
8e669ac1 | 3151 | #endif |
3cc3f762 JH |
3152 | where == ACL_WHERE_PREDATA ? US"DATA" : |
3153 | where == ACL_WHERE_DATA ? US"after DATA" : | |
8ccd00b1 | 3154 | #ifndef DISABLE_PRDR |
3cc3f762 | 3155 | where == ACL_WHERE_PRDR ? US"after DATA PRDR" : |
fd98a5c6 | 3156 | #endif |
3cc3f762 JH |
3157 | smtp_cmd_data ? |
3158 | string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) : | |
3159 | string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]); | |
059ec3d9 PH |
3160 | |
3161 | if (drop) rc = FAIL; | |
3162 | ||
4e88a19f | 3163 | /* Set the default SMTP code, and allow a user message to change it. */ |
a5bd321b | 3164 | |
4f6ae5c3 JH |
3165 | smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451"; |
3166 | smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg, | |
3167 | where != ACL_WHERE_VRFY); | |
a5bd321b | 3168 | |
059ec3d9 PH |
3169 | /* We used to have sender_address here; however, there was a bug that was not |
3170 | updating sender_address after a rewrite during a verify. When this bug was | |
3171 | fixed, sender_address at this point became the rewritten address. I'm not sure | |
3172 | this is what should be logged, so I've changed to logging the unrewritten | |
3173 | address to retain backward compatibility. */ | |
3174 | ||
8523533c | 3175 | #ifndef WITH_CONTENT_SCAN |
059ec3d9 | 3176 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA) |
8523533c TK |
3177 | #else |
3178 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME) | |
3179 | #endif | |
059ec3d9 | 3180 | { |
b98bb9ac PP |
3181 | sender_info = string_sprintf("F=<%s>%s%s%s%s ", |
3182 | sender_address_unrewritten ? sender_address_unrewritten : sender_address, | |
3183 | sender_host_authenticated ? US" A=" : US"", | |
3184 | sender_host_authenticated ? sender_host_authenticated : US"", | |
3185 | sender_host_authenticated && authenticated_id ? US":" : US"", | |
3186 | sender_host_authenticated && authenticated_id ? authenticated_id : US"" | |
3187 | ); | |
059ec3d9 PH |
3188 | } |
3189 | ||
3190 | /* If there's been a sender verification failure with a specific message, and | |
3191 | we have not sent a response about it yet, do so now, as a preliminary line for | |
278c6e6c PH |
3192 | failures, but not defers. However, always log it for defer, and log it for fail |
3193 | unless the sender_verify_fail log selector has been turned off. */ | |
059ec3d9 | 3194 | |
02b41d71 | 3195 | if (sender_verified_failed && |
059ec3d9 PH |
3196 | !testflag(sender_verified_failed, af_sverify_told)) |
3197 | { | |
2679d413 PH |
3198 | BOOL save_rcpt_in_progress = rcpt_in_progress; |
3199 | rcpt_in_progress = FALSE; /* So as not to treat these as the error */ | |
3200 | ||
059ec3d9 PH |
3201 | setflag(sender_verified_failed, af_sverify_told); |
3202 | ||
6c6d6e48 | 3203 | if (rc != FAIL || LOGGING(sender_verify_fail)) |
278c6e6c PH |
3204 | log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s", |
3205 | host_and_ident(TRUE), | |
3206 | ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail", | |
3207 | sender_verified_failed->address, | |
3208 | (sender_verified_failed->message == NULL)? US"" : | |
3209 | string_sprintf(": %s", sender_verified_failed->message)); | |
059ec3d9 | 3210 | |
02b41d71 | 3211 | if (rc == FAIL && sender_verified_failed->user_message) |
a5bd321b | 3212 | smtp_respond(smtp_code, codelen, FALSE, string_sprintf( |
059ec3d9 PH |
3213 | testflag(sender_verified_failed, af_verify_pmfail)? |
3214 | "Postmaster verification failed while checking <%s>\n%s\n" | |
3215 | "Several RFCs state that you are required to have a postmaster\n" | |
3216 | "mailbox for each mail domain. This host does not accept mail\n" | |
3217 | "from domains whose servers reject the postmaster address." | |
3218 | : | |
3219 | testflag(sender_verified_failed, af_verify_nsfail)? | |
3220 | "Callback setup failed while verifying <%s>\n%s\n" | |
3221 | "The initial connection, or a HELO or MAIL FROM:<> command was\n" | |
3222 | "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n" | |
3223 | "RFC requirements, and stops you from receiving standard bounce\n" | |
3224 | "messages. This host does not accept mail from domains whose servers\n" | |
3225 | "refuse bounces." | |
3226 | : | |
3227 | "Verification failed for <%s>\n%s", | |
3228 | sender_verified_failed->address, | |
3229 | sender_verified_failed->user_message)); | |
2679d413 PH |
3230 | |
3231 | rcpt_in_progress = save_rcpt_in_progress; | |
059ec3d9 PH |
3232 | } |
3233 | ||
3234 | /* Sort out text for logging */ | |
3235 | ||
3cc3f762 JH |
3236 | log_msg = log_msg ? string_sprintf(": %s", log_msg) : US""; |
3237 | if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0; | |
059ec3d9 PH |
3238 | |
3239 | /* Send permanent failure response to the command, but the code used isn't | |
3240 | always a 5xx one - see comments at the start of this function. If the original | |
3241 | rc was FAIL_DROP we drop the connection and yield 2. */ | |
3242 | ||
ff5929e3 JH |
3243 | if (rc == FAIL) |
3244 | smtp_respond(smtp_code, codelen, TRUE, | |
3245 | user_msg ? user_msg : US"Administrative prohibition"); | |
059ec3d9 PH |
3246 | |
3247 | /* Send temporary failure response to the command. Don't give any details, | |
3248 | unless acl_temp_details is set. This is TRUE for a callout defer, a "defer" | |
3249 | verb, and for a header verify when smtp_return_error_details is set. | |
3250 | ||
3251 | This conditional logic is all somewhat of a mess because of the odd | |
3252 | interactions between temp_details and return_error_details. One day it should | |
3253 | be re-implemented in a tidier fashion. */ | |
3254 | ||
3255 | else | |
ff5929e3 | 3256 | if (acl_temp_details && user_msg) |
059ec3d9 | 3257 | { |
ff5929e3 JH |
3258 | if ( smtp_return_error_details |
3259 | && sender_verified_failed | |
3260 | && sender_verified_failed->message | |
3261 | ) | |
a5bd321b | 3262 | smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message); |
ff5929e3 | 3263 | |
a5bd321b | 3264 | smtp_respond(smtp_code, codelen, TRUE, user_msg); |
059ec3d9 PH |
3265 | } |
3266 | else | |
a5bd321b PH |
3267 | smtp_respond(smtp_code, codelen, TRUE, |
3268 | US"Temporary local problem - please try later"); | |
059ec3d9 | 3269 | |
6ea85e9a PH |
3270 | /* Log the incident to the logs that are specified by log_reject_target |
3271 | (default main, reject). This can be empty to suppress logging of rejections. If | |
3272 | the connection is not forcibly to be dropped, return 0. Otherwise, log why it | |
3273 | is closing if required and return 2. */ | |
059ec3d9 | 3274 | |
6ea85e9a | 3275 | if (log_reject_target != 0) |
887291d2 | 3276 | { |
e45a1c37 | 3277 | #ifdef SUPPORT_TLS |
fc16abb4 JH |
3278 | uschar * tls = s_tlslog(NULL, NULL, NULL); |
3279 | if (!tls) tls = US""; | |
e45a1c37 | 3280 | #else |
fc16abb4 | 3281 | uschar * tls = US""; |
e45a1c37 | 3282 | #endif |
3cc3f762 JH |
3283 | log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0, |
3284 | log_reject_target, "%s%s%s %s%srejected %s%s", | |
fc16abb4 JH |
3285 | LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"", |
3286 | host_and_ident(TRUE), | |
3287 | tls, | |
3288 | sender_info, | |
3289 | rc == FAIL ? US"" : US"temporarily ", | |
3290 | what, log_msg); | |
887291d2 | 3291 | } |
059ec3d9 PH |
3292 | |
3293 | if (!drop) return 0; | |
3294 | ||
3295 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL", | |
3296 | smtp_get_connection_info()); | |
8f128379 PH |
3297 | |
3298 | /* Run the not-quit ACL, but without any custom messages. This should not be a | |
3299 | problem, because we get here only if some other ACL has issued "drop", and | |
3300 | in that case, *its* custom messages will have been used above. */ | |
3301 | ||
3302 | smtp_notquit_exit(US"acl-drop", NULL, NULL); | |
059ec3d9 PH |
3303 | return 2; |
3304 | } | |
3305 | ||
3306 | ||
3307 | ||
3308 | ||
8f128379 PH |
3309 | /************************************************* |
3310 | * Handle SMTP exit when QUIT is not given * | |
3311 | *************************************************/ | |
3312 | ||
3313 | /* This function provides a logging/statistics hook for when an SMTP connection | |
3314 | is dropped on the floor or the other end goes away. It's a global function | |
3315 | because it's called from receive.c as well as this module. As well as running | |
3316 | the NOTQUIT ACL, if there is one, this function also outputs a final SMTP | |
3317 | response, either with a custom message from the ACL, or using a default. There | |
3318 | is one case, however, when no message is output - after "drop". In that case, | |
3319 | the ACL that obeyed "drop" has already supplied the custom message, and NULL is | |
3320 | passed to this function. | |
3321 | ||
3322 | In case things go wrong while processing this function, causing an error that | |
4c04137d | 3323 | may re-enter this function, there is a recursion check. |
8f128379 PH |
3324 | |
3325 | Arguments: | |
3326 | reason What $smtp_notquit_reason will be set to in the ACL; | |
3327 | if NULL, the ACL is not run | |
3328 | code The error code to return as part of the response | |
3329 | defaultrespond The default message if there's no user_msg | |
3330 | ||
3331 | Returns: Nothing | |
3332 | */ | |
3333 | ||
3334 | void | |
3335 | smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...) | |
3336 | { | |
3337 | int rc; | |
3338 | uschar *user_msg = NULL; | |
3339 | uschar *log_msg = NULL; | |
3340 | ||
3341 | /* Check for recursive acll */ | |
3342 | ||
3343 | if (smtp_exit_function_called) | |
3344 | { | |
3345 | log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)", | |
3346 | reason); | |
3347 | return; | |
3348 | } | |
3349 | smtp_exit_function_called = TRUE; | |
3350 | ||
3351 | /* Call the not-QUIT ACL, if there is one, unless no reason is given. */ | |
3352 | ||
eea0defe | 3353 | if (acl_smtp_notquit && reason) |
8f128379 PH |
3354 | { |
3355 | smtp_notquit_reason = reason; | |
eea0defe JB |
3356 | if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg, |
3357 | &log_msg)) == ERROR) | |
8f128379 PH |
3358 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s", |
3359 | log_msg); | |
3360 | } | |
3361 | ||
3362 | /* Write an SMTP response if we are expected to give one. As the default | |
3363 | responses are all internal, they should always fit in the buffer, but code a | |
3364 | warning, just in case. Note that string_vformat() still leaves a complete | |
3365 | string, even if it is incomplete. */ | |
3366 | ||
eea0defe | 3367 | if (code && defaultrespond) |
8f128379 | 3368 | { |
eea0defe JB |
3369 | if (user_msg) |
3370 | smtp_respond(code, 3, TRUE, user_msg); | |
3371 | else | |
8f128379 PH |
3372 | { |
3373 | uschar buffer[128]; | |
3374 | va_list ap; | |
3375 | va_start(ap, defaultrespond); | |
3376 | if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap)) | |
3377 | log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()"); | |
925ac8e4 | 3378 | smtp_printf("%s %s\r\n", FALSE, code, buffer); |
8f128379 PH |
3379 | va_end(ap); |
3380 | } | |
8f128379 PH |
3381 | mac_smtp_fflush(); |
3382 | } | |
3383 | } | |
3384 | ||
3385 | ||
3386 | ||
3387 | ||
d7b47fd0 PH |
3388 | /************************************************* |
3389 | * Verify HELO argument * | |
3390 | *************************************************/ | |
3391 | ||
3392 | /* This function is called if helo_verify_hosts or helo_try_verify_hosts is | |
3393 | matched. It is also called from ACL processing if verify = helo is used and | |
3394 | verification was not previously tried (i.e. helo_try_verify_hosts was not | |
3395 | matched). The result of its processing is to set helo_verified and | |
3396 | helo_verify_failed. These variables should both be FALSE for this function to | |
3397 | be called. | |
3398 | ||
3399 | Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow | |
3400 | for IPv6 ::ffff: literals. | |
3401 | ||
3402 | Argument: none | |
3403 | Returns: TRUE if testing was completed; | |
3404 | FALSE on a temporary failure | |
3405 | */ | |
3406 | ||
3407 | BOOL | |
3408 | smtp_verify_helo(void) | |
3409 | { | |
3410 | BOOL yield = TRUE; | |
3411 | ||
3412 | HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n", | |
3413 | sender_helo_name); | |
3414 | ||
3415 | if (sender_helo_name == NULL) | |
3416 | { | |
3417 | HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n"); | |
3418 | } | |
3419 | ||
d1d5595c PH |
3420 | /* Deal with the case of -bs without an IP address */ |
3421 | ||
3422 | else if (sender_host_address == NULL) | |
3423 | { | |
3424 | HDEBUG(D_receive) debug_printf("no client IP address: assume success\n"); | |
3425 | helo_verified = TRUE; | |
3426 | } | |
3427 | ||
3428 | /* Deal with the more common case when there is a sending IP address */ | |
3429 | ||
d7b47fd0 PH |
3430 | else if (sender_helo_name[0] == '[') |
3431 | { | |
3432 | helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address, | |
3433 | Ustrlen(sender_host_address)) == 0; | |
3434 | ||
3435 | #if HAVE_IPV6 | |
3436 | if (!helo_verified) | |
3437 | { | |
3438 | if (strncmpic(sender_host_address, US"::ffff:", 7) == 0) | |
3439 | helo_verified = Ustrncmp(sender_helo_name + 1, | |
3440 | sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0; | |
3441 | } | |
3442 | #endif | |
3443 | ||
3444 | HDEBUG(D_receive) | |
3445 | { if (helo_verified) debug_printf("matched host address\n"); } | |
3446 | } | |
3447 | ||
3448 | /* Do a reverse lookup if one hasn't already given a positive or negative | |
3449 | response. If that fails, or the name doesn't match, try checking with a forward | |
3450 | lookup. */ | |
3451 | ||
3452 | else | |
3453 | { | |
3454 | if (sender_host_name == NULL && !host_lookup_failed) | |
3455 | yield = host_name_lookup() != DEFER; | |
3456 | ||
3457 | /* If a host name is known, check it and all its aliases. */ | |
3458 | ||
1705dd20 JH |
3459 | if (sender_host_name) |
3460 | if ((helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0)) | |
d7b47fd0 | 3461 | { |
1705dd20 | 3462 | sender_helo_dnssec = sender_host_dnssec; |
d7b47fd0 PH |
3463 | HDEBUG(D_receive) debug_printf("matched host name\n"); |
3464 | } | |
3465 | else | |
3466 | { | |
3467 | uschar **aliases = sender_host_aliases; | |
1705dd20 JH |
3468 | while (*aliases) |
3469 | if ((helo_verified = strcmpic(*aliases++, sender_helo_name) == 0)) | |
3470 | { | |
3471 | sender_helo_dnssec = sender_host_dnssec; | |
3472 | break; | |
3473 | } | |
3474 | ||
3475 | HDEBUG(D_receive) if (helo_verified) | |
d7b47fd0 | 3476 | debug_printf("matched alias %s\n", *(--aliases)); |
d7b47fd0 | 3477 | } |
d7b47fd0 PH |
3478 | |
3479 | /* Final attempt: try a forward lookup of the helo name */ | |
3480 | ||
3481 | if (!helo_verified) | |
3482 | { | |
3483 | int rc; | |
3484 | host_item h; | |
1705dd20 JH |
3485 | dnssec_domains d; |
3486 | host_item *hh; | |
3487 | ||
d7b47fd0 PH |
3488 | h.name = sender_helo_name; |
3489 | h.address = NULL; | |
3490 | h.mx = MX_NONE; | |
3491 | h.next = NULL; | |
1705dd20 JH |
3492 | d.request = US"*"; |
3493 | d.require = US""; | |
3494 | ||
d7b47fd0 PH |
3495 | HDEBUG(D_receive) debug_printf("getting IP address for %s\n", |
3496 | sender_helo_name); | |
1705dd20 JH |
3497 | rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A, |
3498 | NULL, NULL, NULL, &d, NULL, NULL); | |
d7b47fd0 | 3499 | if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL) |
1705dd20 | 3500 | for (hh = &h; hh; hh = hh->next) |
d7b47fd0 PH |
3501 | if (Ustrcmp(hh->address, sender_host_address) == 0) |
3502 | { | |
3503 | helo_verified = TRUE; | |
1705dd20 | 3504 | if (h.dnssec == DS_YES) sender_helo_dnssec = TRUE; |
d7b47fd0 | 3505 | HDEBUG(D_receive) |
1705dd20 JH |
3506 | { |
3507 | debug_printf("IP address for %s matches calling address\n" | |
3508 | "Forward DNS security status: %sverified\n", | |
3509 | sender_helo_name, sender_helo_dnssec ? "" : "un"); | |
3510 | } | |
d7b47fd0 PH |
3511 | break; |
3512 | } | |
d7b47fd0 PH |
3513 | } |
3514 | } | |
3515 | ||
d1d5595c | 3516 | if (!helo_verified) helo_verify_failed = TRUE; /* We've tried ... */ |
d7b47fd0 PH |
3517 | return yield; |
3518 | } | |
3519 | ||
3520 | ||
3521 | ||
3522 | ||
4e88a19f PH |
3523 | /************************************************* |
3524 | * Send user response message * | |
3525 | *************************************************/ | |
3526 | ||
3527 | /* This function is passed a default response code and a user message. It calls | |
3528 | smtp_message_code() to check and possibly modify the response code, and then | |
3529 | calls smtp_respond() to transmit the response. I put this into a function | |
3530 | just to avoid a lot of repetition. | |
3531 | ||
3532 | Arguments: | |
3533 | code the response code | |
3534 | user_msg the user message | |
3535 | ||
3536 | Returns: nothing | |
3537 | */ | |
3538 | ||
3539 | static void | |
3540 | smtp_user_msg(uschar *code, uschar *user_msg) | |
3541 | { | |
3542 | int len = 3; | |
4f6ae5c3 | 3543 | smtp_message_code(&code, &len, &user_msg, NULL, TRUE); |
4e88a19f PH |
3544 | smtp_respond(code, len, TRUE, user_msg); |
3545 | } | |
3546 | ||
3547 | ||
3548 | ||
b3ef41c9 JH |
3549 | static int |
3550 | smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss) | |
3551 | { | |
3552 | const uschar *set_id = NULL; | |
3553 | int rc, i; | |
3554 | ||
3555 | /* Run the checking code, passing the remainder of the command line as | |
3556 | data. Initials the $auth<n> variables as empty. Initialize $0 empty and set | |
3557 | it as the only set numerical variable. The authenticator may set $auth<n> | |
3558 | and also set other numeric variables. The $auth<n> variables are preferred | |
3559 | nowadays; the numerical variables remain for backwards compatibility. | |
3560 | ||
3561 | Afterwards, have a go at expanding the set_id string, even if | |
3562 | authentication failed - for bad passwords it can be useful to log the | |
3563 | userid. On success, require set_id to expand and exist, and put it in | |
3564 | authenticated_id. Save this in permanent store, as the working store gets | |
3565 | reset at HELO, RSET, etc. */ | |
3566 | ||
3567 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; | |
3568 | expand_nmax = 0; | |
3569 | expand_nlength[0] = 0; /* $0 contains nothing */ | |
3570 | ||
3571 | rc = (au->info->servercode)(au, smtp_cmd_data); | |
3572 | if (au->set_id) set_id = expand_string(au->set_id); | |
3573 | expand_nmax = -1; /* Reset numeric variables */ | |
3574 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */ | |
3575 | ||
3576 | /* The value of authenticated_id is stored in the spool file and printed in | |
3577 | log lines. It must not contain binary zeros or newline characters. In | |
3578 | normal use, it never will, but when playing around or testing, this error | |
3579 | can (did) happen. To guard against this, ensure that the id contains only | |
3580 | printing characters. */ | |
3581 | ||
3582 | if (set_id) set_id = string_printing(set_id); | |
3583 | ||
3584 | /* For the non-OK cases, set up additional logging data if set_id | |
3585 | is not empty. */ | |
3586 | ||
3587 | if (rc != OK) | |
3588 | set_id = set_id && *set_id | |
3589 | ? string_sprintf(" (set_id=%s)", set_id) : US""; | |
3590 | ||
3591 | /* Switch on the result */ | |
3592 | ||
3593 | switch(rc) | |
3594 | { | |
3595 | case OK: | |
3596 | if (!au->set_id || set_id) /* Complete success */ | |
3597 | { | |
3598 | if (set_id) authenticated_id = string_copy_malloc(set_id); | |
3599 | sender_host_authenticated = au->name; | |
3600 | authentication_failed = FALSE; | |
3601 | authenticated_fail_id = NULL; /* Impossible to already be set? */ | |
3602 | ||
3603 | received_protocol = | |
3604 | (sender_host_address ? protocols : protocols_local) | |
3605 | [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)]; | |
3606 | *s = *ss = US"235 Authentication succeeded"; | |
3607 | authenticated_by = au; | |
3608 | break; | |
3609 | } | |
3610 | ||
3611 | /* Authentication succeeded, but we failed to expand the set_id string. | |
3612 | Treat this as a temporary error. */ | |
3613 | ||
3614 | auth_defer_msg = expand_string_message; | |
3615 | /* Fall through */ | |
3616 | ||
3617 | case DEFER: | |
3618 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3619 | *s = string_sprintf("435 Unable to authenticate at present%s", | |
3620 | auth_defer_user_msg); | |
3621 | *ss = string_sprintf("435 Unable to authenticate at present%s: %s", | |
3622 | set_id, auth_defer_msg); | |
3623 | break; | |
3624 | ||
3625 | case BAD64: | |
3626 | *s = *ss = US"501 Invalid base64 data"; | |
3627 | break; | |
3628 | ||
3629 | case CANCELLED: | |
3630 | *s = *ss = US"501 Authentication cancelled"; | |
3631 | break; | |
3632 | ||
3633 | case UNEXPECTED: | |
3634 | *s = *ss = US"553 Initial data not expected"; | |
3635 | break; | |
3636 | ||
3637 | case FAIL: | |
3638 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3639 | *s = US"535 Incorrect authentication data"; | |
3640 | *ss = string_sprintf("535 Incorrect authentication data%s", set_id); | |
3641 | break; | |
3642 | ||
3643 | default: | |
3644 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3645 | *s = US"435 Internal error"; | |
3646 | *ss = string_sprintf("435 Internal error%s: return %d from authentication " | |
3647 | "check", set_id, rc); | |
3648 | break; | |
3649 | } | |
3650 | ||
3651 | return rc; | |
3652 | } | |
3653 | ||
3654 | ||
3655 | ||
2685d6e0 JH |
3656 | |
3657 | ||
3658 | static int | |
3659 | qualify_recipient(uschar ** recipient, uschar * smtp_cmd_data, uschar * tag) | |
3660 | { | |
3661 | int rd; | |
3662 | if (allow_unqualified_recipient || strcmpic(*recipient, US"postmaster") == 0) | |
3663 | { | |
3664 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
3665 | *recipient); | |
3666 | rd = Ustrlen(recipient) + 1; | |
3667 | *recipient = rewrite_address_qualify(*recipient, TRUE); | |
3668 | return rd; | |
3669 | } | |
925ac8e4 | 3670 | smtp_printf("501 %s: recipient address must contain a domain\r\n", FALSE, |
2685d6e0 JH |
3671 | smtp_cmd_data); |
3672 | log_write(L_smtp_syntax_error, | |
3673 | LOG_MAIN|LOG_REJECT, "unqualified %s rejected: <%s> %s%s", | |
3674 | tag, *recipient, host_and_ident(TRUE), host_lookup_msg); | |
3675 | return 0; | |
3676 | } | |
3677 | ||
3678 | ||
3679 | ||
3680 | ||
7e3ce68e JH |
3681 | static void |
3682 | smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp) | |
3683 | { | |
3684 | HAD(SCH_QUIT); | |
3685 | incomplete_transaction_log(US"QUIT"); | |
60d10ce7 | 3686 | if (acl_smtp_quit) |
7e3ce68e JH |
3687 | { |
3688 | int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp); | |
3689 | if (rc == ERROR) | |
3690 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
3691 | *log_msgp); | |
3692 | } | |
3693 | if (*user_msgp) | |
3694 | smtp_respond(US"221", 3, TRUE, *user_msgp); | |
3695 | else | |
925ac8e4 | 3696 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); |
7e3ce68e JH |
3697 | |
3698 | #ifdef SUPPORT_TLS | |
3699 | tls_close(TRUE, TRUE); | |
3700 | #endif | |
3701 | ||
3702 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", | |
3703 | smtp_get_connection_info()); | |
3704 | } | |
3705 | ||
3706 | ||
3707 | static void | |
3708 | smtp_rset_handler(void) | |
3709 | { | |
3710 | HAD(SCH_RSET); | |
3711 | incomplete_transaction_log(US"RSET"); | |
925ac8e4 | 3712 | smtp_printf("250 Reset OK\r\n", FALSE); |
7e3ce68e JH |
3713 | cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE; |
3714 | } | |
3715 | ||
3716 | ||
3717 | ||
059ec3d9 PH |
3718 | /************************************************* |
3719 | * Initialize for SMTP incoming message * | |
3720 | *************************************************/ | |
3721 | ||
3722 | /* This function conducts the initial dialogue at the start of an incoming SMTP | |
3723 | message, and builds a list of recipients. However, if the incoming message | |
3724 | is part of a batch (-bS option) a separate function is called since it would | |
3725 | be messy having tests splattered about all over this function. This function | |
3726 | therefore handles the case where interaction is occurring. The input and output | |
3727 | files are set up in smtp_in and smtp_out. | |
3728 | ||
3729 | The global recipients_list is set to point to a vector of recipient_item | |
3730 | blocks, whose number is given by recipients_count. This is extended by the | |
3731 | receive_add_recipient() function. The global variable sender_address is set to | |
3732 | the sender's address. The yield is +1 if a message has been successfully | |
3733 | started, 0 if a QUIT command was encountered or the connection was refused from | |
3734 | the particular host, or -1 if the connection was lost. | |
3735 | ||
3736 | Argument: none | |
3737 | ||
3738 | Returns: > 0 message successfully started (reached DATA) | |
3739 | = 0 QUIT read or end of file reached or call refused | |
3740 | < 0 lost connection | |
3741 | */ | |
3742 | ||
3743 | int | |
3744 | smtp_setup_msg(void) | |
3745 | { | |
3746 | int done = 0; | |
3747 | BOOL toomany = FALSE; | |
3748 | BOOL discarded = FALSE; | |
3749 | BOOL last_was_rej_mail = FALSE; | |
3750 | BOOL last_was_rcpt = FALSE; | |
3751 | void *reset_point = store_get(0); | |
3752 | ||
3753 | DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n"); | |
3754 | ||
3755 | /* Reset for start of new message. We allow one RSET not to be counted as a | |
3756 | nonmail command, for those MTAs that insist on sending it between every | |
3757 | message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of | |
3758 | TLS between messages (an Exim client may do this if it has messages queued up | |
3759 | for the host). Note: we do NOT reset AUTH at this point. */ | |
3760 | ||
3761 | smtp_reset(reset_point); | |
3762 | message_ended = END_NOTSTARTED; | |
3763 | ||
7e3ce68e JH |
3764 | chunking_state = chunking_offered ? CHUNKING_OFFERED : CHUNKING_NOT_OFFERED; |
3765 | ||
059ec3d9 PH |
3766 | cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE; |
3767 | cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE; | |
3768 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
3769 | #ifdef SUPPORT_TLS | |
3770 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE; | |
b3ef41c9 | 3771 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; |
059ec3d9 PH |
3772 | #endif |
3773 | ||
3774 | /* Set the local signal handler for SIGTERM - it tries to end off tidily */ | |
3775 | ||
3776 | os_non_restarting_signal(SIGTERM, command_sigterm_handler); | |
3777 | ||
3778 | /* Batched SMTP is handled in a different function. */ | |
3779 | ||
3780 | if (smtp_batched_input) return smtp_setup_batch_msg(); | |
3781 | ||
3782 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
3783 | value. The values are 2 larger than the required yield of the function. */ | |
3784 | ||
3785 | while (done <= 0) | |
3786 | { | |
55414b25 | 3787 | const uschar **argv; |
059ec3d9 PH |
3788 | uschar *etrn_command; |
3789 | uschar *etrn_serialize_key; | |
3790 | uschar *errmess; | |
4e88a19f PH |
3791 | uschar *log_msg, *smtp_code; |
3792 | uschar *user_msg = NULL; | |
059ec3d9 PH |
3793 | uschar *recipient = NULL; |
3794 | uschar *hello = NULL; | |
059ec3d9 PH |
3795 | uschar *s, *ss; |
3796 | BOOL was_rej_mail = FALSE; | |
3797 | BOOL was_rcpt = FALSE; | |
3798 | void (*oldsignal)(int); | |
3799 | pid_t pid; | |
3800 | int start, end, sender_domain, recipient_domain; | |
3801 | int ptr, size, rc; | |
aa7751be | 3802 | int c; |
059ec3d9 | 3803 | auth_instance *au; |
6c1c3d1d WB |
3804 | uschar *orcpt = NULL; |
3805 | int flags; | |
059ec3d9 | 3806 | |
16be7f11 | 3807 | #ifdef AUTH_TLS |
b3ef41c9 JH |
3808 | /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */ |
3809 | if ( tls_in.active >= 0 | |
3810 | && tls_in.peercert | |
3811 | && tls_in.certificate_verified | |
3812 | && cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd | |
3813 | ) | |
3814 | { | |
3815 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = FALSE; | |
4f6ae5c3 JH |
3816 | if ( acl_smtp_auth |
3817 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
3818 | &user_msg, &log_msg)) != OK | |
3819 | ) | |
b3ef41c9 | 3820 | { |
4f6ae5c3 JH |
3821 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); |
3822 | continue; | |
b3ef41c9 JH |
3823 | } |
3824 | ||
3825 | for (au = auths; au; au = au->next) | |
3826 | if (strcmpic(US"tls", au->driver_name) == 0) | |
3827 | { | |
3828 | smtp_cmd_data = NULL; | |
3829 | ||
805bb5c3 | 3830 | if (smtp_in_auth(au, &s, &ss) == OK) |
cb570b5e | 3831 | { DEBUG(D_auth) debug_printf("tls auth succeeded\n"); } |
805bb5c3 | 3832 | else |
cb570b5e | 3833 | { DEBUG(D_auth) debug_printf("tls auth not succeeded\n"); } |
b3ef41c9 JH |
3834 | break; |
3835 | } | |
3836 | } | |
3837 | #endif | |
3838 | ||
8d330698 JH |
3839 | #ifdef TCP_QUICKACK |
3840 | if (smtp_in) /* Avoid pure-ACKs while in cmd pingpong phase */ | |
3841 | (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK, | |
3842 | US &off, sizeof(off)); | |
3843 | #endif | |
3844 | ||
bd8fbe36 | 3845 | switch(smtp_read_command(TRUE, GETC_BUFFER_UNLIMITED)) |
059ec3d9 PH |
3846 | { |
3847 | /* The AUTH command is not permitted to occur inside a transaction, and may | |
c46782ef PH |
3848 | occur successfully only once per connection. Actually, that isn't quite |
3849 | true. When TLS is started, all previous information about a connection must | |
3850 | be discarded, so a new AUTH is permitted at that time. | |
3851 | ||
3852 | AUTH may only be used when it has been advertised. However, it seems that | |
3853 | there are clients that send AUTH when it hasn't been advertised, some of | |
3854 | them even doing this after HELO. And there are MTAs that accept this. Sigh. | |
3855 | So there's a get-out that allows this to happen. | |
059ec3d9 PH |
3856 | |
3857 | AUTH is initially labelled as a "nonmail command" so that one occurrence | |
3858 | doesn't get counted. We change the label here so that multiple failing | |
3859 | AUTHS will eventually hit the nonmail threshold. */ | |
3860 | ||
3861 | case AUTH_CMD: | |
b4ed4da0 | 3862 | HAD(SCH_AUTH); |
059ec3d9 PH |
3863 | authentication_failed = TRUE; |
3864 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE; | |
3865 | ||
c46782ef | 3866 | if (!auth_advertised && !allow_auth_unadvertised) |
059ec3d9 PH |
3867 | { |
3868 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3869 | US"AUTH command used when not advertised"); | |
3870 | break; | |
3871 | } | |
b3ef41c9 | 3872 | if (sender_host_authenticated) |
059ec3d9 PH |
3873 | { |
3874 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3875 | US"already authenticated"); | |
3876 | break; | |
3877 | } | |
b3ef41c9 | 3878 | if (sender_address) |
059ec3d9 PH |
3879 | { |
3880 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3881 | US"not permitted in mail transaction"); | |
3882 | break; | |
3883 | } | |
3884 | ||
3885 | /* Check the ACL */ | |
3886 | ||
4f6ae5c3 JH |
3887 | if ( acl_smtp_auth |
3888 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
3889 | &user_msg, &log_msg)) != OK | |
3890 | ) | |
059ec3d9 | 3891 | { |
4f6ae5c3 JH |
3892 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); |
3893 | break; | |
059ec3d9 PH |
3894 | } |
3895 | ||
3896 | /* Find the name of the requested authentication mechanism. */ | |
3897 | ||
ca86f471 PH |
3898 | s = smtp_cmd_data; |
3899 | while ((c = *smtp_cmd_data) != 0 && !isspace(c)) | |
059ec3d9 PH |
3900 | { |
3901 | if (!isalnum(c) && c != '-' && c != '_') | |
3902 | { | |
3903 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
3904 | US"invalid character in authentication mechanism name"); | |
3905 | goto COMMAND_LOOP; | |
3906 | } | |
ca86f471 | 3907 | smtp_cmd_data++; |
059ec3d9 PH |
3908 | } |
3909 | ||
3910 | /* If not at the end of the line, we must be at white space. Terminate the | |
3911 | name and move the pointer on to any data that may be present. */ | |
3912 | ||
ca86f471 | 3913 | if (*smtp_cmd_data != 0) |
059ec3d9 | 3914 | { |
ca86f471 PH |
3915 | *smtp_cmd_data++ = 0; |
3916 | while (isspace(*smtp_cmd_data)) smtp_cmd_data++; | |
059ec3d9 PH |
3917 | } |
3918 | ||
3919 | /* Search for an authentication mechanism which is configured for use | |
c46782ef PH |
3920 | as a server and which has been advertised (unless, sigh, allow_auth_ |
3921 | unadvertised is set). */ | |
059ec3d9 | 3922 | |
b3ef41c9 | 3923 | for (au = auths; au; au = au->next) |
059ec3d9 | 3924 | if (strcmpic(s, au->public_name) == 0 && au->server && |
b3ef41c9 JH |
3925 | (au->advertised || allow_auth_unadvertised)) |
3926 | break; | |
059ec3d9 | 3927 | |
b3ef41c9 | 3928 | if (au) |
059ec3d9 | 3929 | { |
b3ef41c9 | 3930 | c = smtp_in_auth(au, &s, &ss); |
059ec3d9 | 3931 | |
925ac8e4 | 3932 | smtp_printf("%s\r\n", FALSE, s); |
b3ef41c9 JH |
3933 | if (c != OK) |
3934 | log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s", | |
3935 | au->name, host_and_ident(FALSE), ss); | |
059ec3d9 | 3936 | } |
b3ef41c9 JH |
3937 | else |
3938 | done = synprot_error(L_smtp_protocol_error, 504, NULL, | |
3939 | string_sprintf("%s authentication mechanism not supported", s)); | |
059ec3d9 PH |
3940 | |
3941 | break; /* AUTH_CMD */ | |
3942 | ||
3943 | /* The HELO/EHLO commands are permitted to appear in the middle of a | |
3944 | session as well as at the beginning. They have the effect of a reset in | |
3945 | addition to their other functions. Their absence at the start cannot be | |
3946 | taken to be an error. | |
3947 | ||
3948 | RFC 2821 says: | |
3949 | ||
3950 | If the EHLO command is not acceptable to the SMTP server, 501, 500, | |
3951 | or 502 failure replies MUST be returned as appropriate. The SMTP | |
3952 | server MUST stay in the same state after transmitting these replies | |
3953 | that it was in before the EHLO was received. | |
3954 | ||
3955 | Therefore, we do not do the reset until after checking the command for | |
3956 | acceptability. This change was made for Exim release 4.11. Previously | |
3957 | it did the reset first. */ | |
3958 | ||
3959 | case HELO_CMD: | |
b4ed4da0 | 3960 | HAD(SCH_HELO); |
059ec3d9 PH |
3961 | hello = US"HELO"; |
3962 | esmtp = FALSE; | |
3963 | goto HELO_EHLO; | |
3964 | ||
3965 | case EHLO_CMD: | |
b4ed4da0 | 3966 | HAD(SCH_EHLO); |
059ec3d9 PH |
3967 | hello = US"EHLO"; |
3968 | esmtp = TRUE; | |
3969 | ||
3970 | HELO_EHLO: /* Common code for HELO and EHLO */ | |
3971 | cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE; | |
3972 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE; | |
3973 | ||
3974 | /* Reject the HELO if its argument was invalid or non-existent. A | |
3975 | successful check causes the argument to be saved in malloc store. */ | |
3976 | ||
ca86f471 | 3977 | if (!check_helo(smtp_cmd_data)) |
059ec3d9 | 3978 | { |
925ac8e4 | 3979 | smtp_printf("501 Syntactically invalid %s argument(s)\r\n", FALSE, hello); |
059ec3d9 PH |
3980 | |
3981 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically " | |
3982 | "invalid argument(s): %s", hello, host_and_ident(FALSE), | |
3ee512ff PH |
3983 | (*smtp_cmd_argument == 0)? US"(no argument given)" : |
3984 | string_printing(smtp_cmd_argument)); | |
059ec3d9 PH |
3985 | |
3986 | if (++synprot_error_count > smtp_max_synprot_errors) | |
3987 | { | |
3988 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
3989 | "syntax or protocol errors (last command was \"%s\")", | |
0ebc4d69 | 3990 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
3991 | done = 1; |
3992 | } | |
3993 | ||
3994 | break; | |
3995 | } | |
3996 | ||
3997 | /* If sender_host_unknown is true, we have got here via the -bs interface, | |
3998 | not called from inetd. Otherwise, we are running an IP connection and the | |
3999 | host address will be set. If the helo name is the primary name of this | |
4000 | host and we haven't done a reverse lookup, force one now. If helo_required | |
4001 | is set, ensure that the HELO name matches the actual host. If helo_verify | |
4002 | is set, do the same check, but softly. */ | |
4003 | ||
4004 | if (!sender_host_unknown) | |
4005 | { | |
4006 | BOOL old_helo_verified = helo_verified; | |
ca86f471 | 4007 | uschar *p = smtp_cmd_data; |
059ec3d9 PH |
4008 | |
4009 | while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; } | |
4010 | *p = 0; | |
4011 | ||
4012 | /* Force a reverse lookup if HELO quoted something in helo_lookup_domains | |
4013 | because otherwise the log can be confusing. */ | |
4014 | ||
4015 | if (sender_host_name == NULL && | |
4016 | (deliver_domain = sender_helo_name, /* set $domain */ | |
55414b25 | 4017 | match_isinlist(sender_helo_name, CUSS &helo_lookup_domains, 0, |
059ec3d9 PH |
4018 | &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL)) == OK) |
4019 | (void)host_name_lookup(); | |
4020 | ||
4021 | /* Rebuild the fullhost info to include the HELO name (and the real name | |
4022 | if it was looked up.) */ | |
4023 | ||
4024 | host_build_sender_fullhost(); /* Rebuild */ | |
4025 | set_process_info("handling%s incoming connection from %s", | |
817d9f57 | 4026 | (tls_in.active >= 0)? " TLS" : "", host_and_ident(FALSE)); |
059ec3d9 PH |
4027 | |
4028 | /* Verify if configured. This doesn't give much security, but it does | |
d7b47fd0 PH |
4029 | make some people happy to be able to do it. If helo_required is set, |
4030 | (host matches helo_verify_hosts) failure forces rejection. If helo_verify | |
4031 | is set (host matches helo_try_verify_hosts), it does not. This is perhaps | |
4032 | now obsolescent, since the verification can now be requested selectively | |
4033 | at ACL time. */ | |
059ec3d9 | 4034 | |
1705dd20 | 4035 | helo_verified = helo_verify_failed = sender_helo_dnssec = FALSE; |
059ec3d9 PH |
4036 | if (helo_required || helo_verify) |
4037 | { | |
d7b47fd0 | 4038 | BOOL tempfail = !smtp_verify_helo(); |
059ec3d9 PH |
4039 | if (!helo_verified) |
4040 | { | |
4041 | if (helo_required) | |
4042 | { | |
925ac8e4 | 4043 | smtp_printf("%d %s argument does not match calling host\r\n", FALSE, |
059ec3d9 PH |
4044 | tempfail? 451 : 550, hello); |
4045 | log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s", | |
4046 | tempfail? "temporarily " : "", | |
4047 | hello, sender_helo_name, host_and_ident(FALSE)); | |
4048 | helo_verified = old_helo_verified; | |
4049 | break; /* End of HELO/EHLO processing */ | |
4050 | } | |
4051 | HDEBUG(D_all) debug_printf("%s verification failed but host is in " | |
4052 | "helo_try_verify_hosts\n", hello); | |
4053 | } | |
4054 | } | |
4055 | } | |
4056 | ||
8523533c TK |
4057 | #ifdef EXPERIMENTAL_SPF |
4058 | /* set up SPF context */ | |
4059 | spf_init(sender_helo_name, sender_host_address); | |
4060 | #endif | |
4061 | ||
a14e5636 PH |
4062 | /* Apply an ACL check if one is defined; afterwards, recheck |
4063 | synchronization in case the client started sending in a delay. */ | |
059ec3d9 | 4064 | |
4f6ae5c3 JH |
4065 | if (acl_smtp_helo) |
4066 | if ((rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, | |
4067 | &user_msg, &log_msg)) != OK) | |
059ec3d9 PH |
4068 | { |
4069 | done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg); | |
4070 | sender_helo_name = NULL; | |
4071 | host_build_sender_fullhost(); /* Rebuild */ | |
4072 | break; | |
4073 | } | |
a14e5636 | 4074 | else if (!check_sync()) goto SYNC_FAILURE; |
059ec3d9 | 4075 | |
4e88a19f PH |
4076 | /* Generate an OK reply. The default string includes the ident if present, |
4077 | and also the IP address if present. Reflecting back the ident is intended | |
4078 | as a deterrent to mail forgers. For maximum efficiency, and also because | |
4079 | some broken systems expect each response to be in a single packet, arrange | |
4080 | that the entire reply is sent in one write(). */ | |
059ec3d9 PH |
4081 | |
4082 | auth_advertised = FALSE; | |
4083 | pipelining_advertised = FALSE; | |
d1a13eea | 4084 | #ifdef SUPPORT_TLS |
059ec3d9 | 4085 | tls_advertised = FALSE; |
d1a13eea | 4086 | #endif |
6c1c3d1d | 4087 | dsn_advertised = FALSE; |
8c5d388a | 4088 | #ifdef SUPPORT_I18N |
d1a13eea JH |
4089 | smtputf8_advertised = FALSE; |
4090 | #endif | |
059ec3d9 | 4091 | |
d6a96edc | 4092 | smtp_code = US"250 "; /* Default response code plus space*/ |
00580051 | 4093 | if (!user_msg) |
4e88a19f PH |
4094 | { |
4095 | s = string_sprintf("%.3s %s Hello %s%s%s", | |
4096 | smtp_code, | |
4097 | smtp_active_hostname, | |
00580051 JH |
4098 | sender_ident ? sender_ident : US"", |
4099 | sender_ident ? US" at " : US"", | |
4100 | sender_host_name ? sender_host_name : sender_helo_name); | |
4e88a19f PH |
4101 | |
4102 | ptr = Ustrlen(s); | |
4103 | size = ptr + 1; | |
059ec3d9 | 4104 | |
00580051 | 4105 | if (sender_host_address) |
4e88a19f | 4106 | { |
c2f669a4 JH |
4107 | s = string_catn(s, &size, &ptr, US" [", 2); |
4108 | s = string_cat (s, &size, &ptr, sender_host_address); | |
4109 | s = string_catn(s, &size, &ptr, US"]", 1); | |
4e88a19f PH |
4110 | } |
4111 | } | |
4112 | ||
d6a96edc PH |
4113 | /* A user-supplied EHLO greeting may not contain more than one line. Note |
4114 | that the code returned by smtp_message_code() includes the terminating | |
4115 | whitespace character. */ | |
059ec3d9 | 4116 | |
4e88a19f | 4117 | else |
059ec3d9 | 4118 | { |
4e88a19f | 4119 | char *ss; |
d6a96edc | 4120 | int codelen = 4; |
4f6ae5c3 | 4121 | smtp_message_code(&smtp_code, &codelen, &user_msg, NULL, TRUE); |
d6a96edc | 4122 | s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg); |
4e88a19f PH |
4123 | if ((ss = strpbrk(CS s, "\r\n")) != NULL) |
4124 | { | |
4125 | log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain " | |
4126 | "newlines: message truncated: %s", string_printing(s)); | |
4127 | *ss = 0; | |
4128 | } | |
4129 | ptr = Ustrlen(s); | |
4130 | size = ptr + 1; | |
059ec3d9 PH |
4131 | } |
4132 | ||
c2f669a4 | 4133 | s = string_catn(s, &size, &ptr, US"\r\n", 2); |
059ec3d9 PH |
4134 | |
4135 | /* If we received EHLO, we must create a multiline response which includes | |
4136 | the functions supported. */ | |
4137 | ||
4138 | if (esmtp) | |
4139 | { | |
4140 | s[3] = '-'; | |
4141 | ||
4142 | /* I'm not entirely happy with this, as an MTA is supposed to check | |
4143 | that it has enough room to accept a message of maximum size before | |
4144 | it sends this. However, there seems little point in not sending it. | |
4145 | The actual size check happens later at MAIL FROM time. By postponing it | |
4146 | till then, VRFY and EXPN can be used after EHLO when space is short. */ | |
4147 | ||
4148 | if (thismessage_size_limit > 0) | |
4149 | { | |
4e88a19f PH |
4150 | sprintf(CS big_buffer, "%.3s-SIZE %d\r\n", smtp_code, |
4151 | thismessage_size_limit); | |
c2f669a4 | 4152 | s = string_cat(s, &size, &ptr, big_buffer); |
059ec3d9 PH |
4153 | } |
4154 | else | |
4155 | { | |
c2f669a4 JH |
4156 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4157 | s = string_catn(s, &size, &ptr, US"-SIZE\r\n", 7); | |
059ec3d9 PH |
4158 | } |
4159 | ||
4160 | /* Exim does not do protocol conversion or data conversion. It is 8-bit | |
4161 | clean; if it has an 8-bit character in its hand, it just sends it. It | |
4162 | cannot therefore specify 8BITMIME and remain consistent with the RFCs. | |
4163 | However, some users want this option simply in order to stop MUAs | |
4164 | mangling messages that contain top-bit-set characters. It is therefore | |
4165 | provided as an option. */ | |
4166 | ||
4167 | if (accept_8bitmime) | |
4e88a19f | 4168 | { |
c2f669a4 JH |
4169 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4170 | s = string_catn(s, &size, &ptr, US"-8BITMIME\r\n", 11); | |
4e88a19f | 4171 | } |
059ec3d9 | 4172 | |
6c1c3d1d | 4173 | /* Advertise DSN support if configured to do so. */ |
94431adb | 4174 | if (verify_check_host(&dsn_advertise_hosts) != FAIL) |
6c1c3d1d | 4175 | { |
c2f669a4 JH |
4176 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4177 | s = string_catn(s, &size, &ptr, US"-DSN\r\n", 6); | |
6c1c3d1d WB |
4178 | dsn_advertised = TRUE; |
4179 | } | |
6c1c3d1d | 4180 | |
bbc8ed07 JH |
4181 | /* Advertise ETRN/VRFY/EXPN if there's are ACL checking whether a host is |
4182 | permitted to issue them; a check is made when any host actually tries. */ | |
059ec3d9 | 4183 | |
bbc8ed07 | 4184 | if (acl_smtp_etrn) |
059ec3d9 | 4185 | { |
c2f669a4 JH |
4186 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4187 | s = string_catn(s, &size, &ptr, US"-ETRN\r\n", 7); | |
059ec3d9 | 4188 | } |
bbc8ed07 JH |
4189 | if (acl_smtp_vrfy) |
4190 | { | |
4191 | s = string_catn(s, &size, &ptr, smtp_code, 3); | |
4192 | s = string_catn(s, &size, &ptr, US"-VRFY\r\n", 7); | |
4193 | } | |
4194 | if (acl_smtp_expn) | |
059ec3d9 | 4195 | { |
c2f669a4 JH |
4196 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4197 | s = string_catn(s, &size, &ptr, US"-EXPN\r\n", 7); | |
059ec3d9 PH |
4198 | } |
4199 | ||
4200 | /* Exim is quite happy with pipelining, so let the other end know that | |
4201 | it is safe to use it, unless advertising is disabled. */ | |
4202 | ||
cf8b11a5 PH |
4203 | if (pipelining_enable && |
4204 | verify_check_host(&pipelining_advertise_hosts) == OK) | |
059ec3d9 | 4205 | { |
c2f669a4 JH |
4206 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4207 | s = string_catn(s, &size, &ptr, US"-PIPELINING\r\n", 13); | |
059ec3d9 PH |
4208 | sync_cmd_limit = NON_SYNC_CMD_PIPELINING; |
4209 | pipelining_advertised = TRUE; | |
4210 | } | |
4211 | ||
fd98a5c6 | 4212 | |
059ec3d9 PH |
4213 | /* If any server authentication mechanisms are configured, advertise |
4214 | them if the current host is in auth_advertise_hosts. The problem with | |
4215 | advertising always is that some clients then require users to | |
4216 | authenticate (and aren't configurable otherwise) even though it may not | |
4217 | be necessary (e.g. if the host is in host_accept_relay). | |
4218 | ||
4219 | RFC 2222 states that SASL mechanism names contain only upper case | |
4220 | letters, so output the names in upper case, though we actually recognize | |
4221 | them in either case in the AUTH command. */ | |
4222 | ||
b3ef41c9 | 4223 | if ( auths |
16be7f11 | 4224 | #ifdef AUTH_TLS |
b3ef41c9 JH |
4225 | && !sender_host_authenticated |
4226 | #endif | |
4227 | && verify_check_host(&auth_advertise_hosts) == OK | |
4228 | ) | |
4229 | { | |
4230 | auth_instance *au; | |
4231 | BOOL first = TRUE; | |
4232 | for (au = auths; au; au = au->next) | |
8b6b06fe JH |
4233 | { |
4234 | au->advertised = FALSE; | |
4235 | if (au->server) | |
b3ef41c9 | 4236 | { |
8b6b06fe JH |
4237 | DEBUG(D_auth+D_expand) debug_printf_indent( |
4238 | "Evaluating advertise_condition for %s athenticator\n", | |
4239 | au->public_name); | |
4240 | if ( !au->advertise_condition | |
4241 | || expand_check_condition(au->advertise_condition, au->name, | |
4242 | US"authenticator") | |
4243 | ) | |
b3ef41c9 | 4244 | { |
8b6b06fe JH |
4245 | int saveptr; |
4246 | if (first) | |
4247 | { | |
4248 | s = string_catn(s, &size, &ptr, smtp_code, 3); | |
4249 | s = string_catn(s, &size, &ptr, US"-AUTH", 5); | |
4250 | first = FALSE; | |
4251 | auth_advertised = TRUE; | |
4252 | } | |
4253 | saveptr = ptr; | |
4254 | s = string_catn(s, &size, &ptr, US" ", 1); | |
4255 | s = string_cat (s, &size, &ptr, au->public_name); | |
4256 | while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]); | |
4257 | au->advertised = TRUE; | |
b3ef41c9 | 4258 | } |
b3ef41c9 | 4259 | } |
8b6b06fe | 4260 | } |
b3ef41c9 | 4261 | |
c2f669a4 | 4262 | if (!first) s = string_catn(s, &size, &ptr, US"\r\n", 2); |
b3ef41c9 | 4263 | } |
059ec3d9 | 4264 | |
18481de3 | 4265 | /* RFC 3030 CHUNKING */ |
059ec3d9 | 4266 | |
aa368db3 JH |
4267 | if (verify_check_host(&chunking_advertise_hosts) != FAIL) |
4268 | { | |
4269 | s = string_catn(s, &size, &ptr, smtp_code, 3); | |
4270 | s = string_catn(s, &size, &ptr, US"-CHUNKING\r\n", 11); | |
7e3ce68e | 4271 | chunking_offered = TRUE; |
18481de3 | 4272 | chunking_state = CHUNKING_OFFERED; |
aa368db3 JH |
4273 | } |
4274 | ||
18481de3 JH |
4275 | /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer) |
4276 | if it has been included in the binary, and the host matches | |
4277 | tls_advertise_hosts. We must *not* advertise if we are already in a | |
4278 | secure connection. */ | |
4279 | ||
d1a13eea | 4280 | #ifdef SUPPORT_TLS |
817d9f57 | 4281 | if (tls_in.active < 0 && |
059ec3d9 PH |
4282 | verify_check_host(&tls_advertise_hosts) != FAIL) |
4283 | { | |
c2f669a4 JH |
4284 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4285 | s = string_catn(s, &size, &ptr, US"-STARTTLS\r\n", 11); | |
059ec3d9 PH |
4286 | tls_advertised = TRUE; |
4287 | } | |
d1a13eea | 4288 | #endif |
059ec3d9 | 4289 | |
d1a13eea | 4290 | #ifndef DISABLE_PRDR |
fd98a5c6 | 4291 | /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */ |
8ccd00b1 JH |
4292 | if (prdr_enable) |
4293 | { | |
c2f669a4 JH |
4294 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4295 | s = string_catn(s, &size, &ptr, US"-PRDR\r\n", 7); | |
8ccd00b1 | 4296 | } |
d1a13eea JH |
4297 | #endif |
4298 | ||
8c5d388a | 4299 | #ifdef SUPPORT_I18N |
d1a13eea JH |
4300 | if ( accept_8bitmime |
4301 | && verify_check_host(&smtputf8_advertise_hosts) != FAIL) | |
4302 | { | |
c2f669a4 JH |
4303 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4304 | s = string_catn(s, &size, &ptr, US"-SMTPUTF8\r\n", 11); | |
d1a13eea JH |
4305 | smtputf8_advertised = TRUE; |
4306 | } | |
4307 | #endif | |
fd98a5c6 | 4308 | |
059ec3d9 PH |
4309 | /* Finish off the multiline reply with one that is always available. */ |
4310 | ||
c2f669a4 JH |
4311 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
4312 | s = string_catn(s, &size, &ptr, US" HELP\r\n", 7); | |
059ec3d9 PH |
4313 | } |
4314 | ||
4315 | /* Terminate the string (for debug), write it, and note that HELO/EHLO | |
4316 | has been seen. */ | |
4317 | ||
4318 | s[ptr] = 0; | |
4319 | ||
d1a13eea | 4320 | #ifdef SUPPORT_TLS |
925ac8e4 | 4321 | if (tls_in.active >= 0) (void)tls_write(TRUE, s, ptr, FALSE); else |
d1a13eea | 4322 | #endif |
059ec3d9 | 4323 | |
1ac6b2e7 JH |
4324 | { |
4325 | int i = fwrite(s, 1, ptr, smtp_out); i = i; /* compiler quietening */ | |
4326 | } | |
898d150f PH |
4327 | DEBUG(D_receive) |
4328 | { | |
4329 | uschar *cr; | |
4330 | while ((cr = Ustrchr(s, '\r')) != NULL) /* lose CRs */ | |
4331 | memmove(cr, cr + 1, (ptr--) - (cr - s)); | |
4332 | debug_printf("SMTP>> %s", s); | |
4333 | } | |
059ec3d9 | 4334 | helo_seen = TRUE; |
4e88a19f PH |
4335 | |
4336 | /* Reset the protocol and the state, abandoning any previous message. */ | |
e524074d JH |
4337 | received_protocol = |
4338 | (sender_host_address ? protocols : protocols_local) | |
4339 | [ (esmtp | |
4340 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
4341 | : pnormal) | |
4342 | + (tls_in.active >= 0 ? pcrpted : 0) | |
4343 | ]; | |
57cc2785 | 4344 | cancel_cutthrough_connection(TRUE, US"sent EHLO response"); |
4e88a19f PH |
4345 | smtp_reset(reset_point); |
4346 | toomany = FALSE; | |
059ec3d9 PH |
4347 | break; /* HELO/EHLO */ |
4348 | ||
4349 | ||
4350 | /* The MAIL command requires an address as an operand. All we do | |
4351 | here is to parse it for syntactic correctness. The form "<>" is | |
4352 | a special case which converts into an empty string. The start/end | |
4353 | pointers in the original are not used further for this address, as | |
4354 | it is the canonical extracted address which is all that is kept. */ | |
4355 | ||
4356 | case MAIL_CMD: | |
b4ed4da0 | 4357 | HAD(SCH_MAIL); |
059ec3d9 PH |
4358 | smtp_mailcmd_count++; /* Count for limit and ratelimit */ |
4359 | was_rej_mail = TRUE; /* Reset if accepted */ | |
d27f98fe | 4360 | env_mail_type_t * mail_args; /* Sanity check & validate args */ |
059ec3d9 PH |
4361 | |
4362 | if (helo_required && !helo_seen) | |
4363 | { | |
925ac8e4 | 4364 | smtp_printf("503 HELO or EHLO required\r\n", FALSE); |
059ec3d9 PH |
4365 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no " |
4366 | "HELO/EHLO given", host_and_ident(FALSE)); | |
4367 | break; | |
4368 | } | |
4369 | ||
4370 | if (sender_address != NULL) | |
4371 | { | |
4372 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4373 | US"sender already given"); | |
4374 | break; | |
4375 | } | |
4376 | ||
ca86f471 | 4377 | if (smtp_cmd_data[0] == 0) |
059ec3d9 PH |
4378 | { |
4379 | done = synprot_error(L_smtp_protocol_error, 501, NULL, | |
4380 | US"MAIL must have an address operand"); | |
4381 | break; | |
4382 | } | |
4383 | ||
4384 | /* Check to see if the limit for messages per connection would be | |
4385 | exceeded by accepting further messages. */ | |
4386 | ||
4387 | if (smtp_accept_max_per_connection > 0 && | |
4388 | smtp_mailcmd_count > smtp_accept_max_per_connection) | |
4389 | { | |
925ac8e4 | 4390 | smtp_printf("421 too many messages in this connection\r\n", FALSE); |
059ec3d9 PH |
4391 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many " |
4392 | "messages in one connection", host_and_ident(TRUE)); | |
4393 | break; | |
4394 | } | |
4395 | ||
4396 | /* Reset for start of message - even if this is going to fail, we | |
4397 | obviously need to throw away any previous data. */ | |
4398 | ||
57cc2785 | 4399 | cancel_cutthrough_connection(TRUE, US"MAIL received"); |
059ec3d9 PH |
4400 | smtp_reset(reset_point); |
4401 | toomany = FALSE; | |
4402 | sender_data = recipient_data = NULL; | |
4403 | ||
4404 | /* Loop, checking for ESMTP additions to the MAIL FROM command. */ | |
4405 | ||
4406 | if (esmtp) for(;;) | |
4407 | { | |
4408 | uschar *name, *value, *end; | |
4409 | unsigned long int size; | |
d27f98fe | 4410 | BOOL arg_error = FALSE; |
059ec3d9 PH |
4411 | |
4412 | if (!extract_option(&name, &value)) break; | |
4413 | ||
d27f98fe | 4414 | for (mail_args = env_mail_type_list; |
2ef7ed08 | 4415 | mail_args->value != ENV_MAIL_OPT_NULL; |
d27f98fe TL |
4416 | mail_args++ |
4417 | ) | |
d27f98fe TL |
4418 | if (strcmpic(name, mail_args->name) == 0) |
4419 | break; | |
d27f98fe TL |
4420 | if (mail_args->need_value && strcmpic(value, US"") == 0) |
4421 | break; | |
059ec3d9 | 4422 | |
d27f98fe | 4423 | switch(mail_args->value) |
059ec3d9 | 4424 | { |
d27f98fe TL |
4425 | /* Handle SIZE= by reading the value. We don't do the check till later, |
4426 | in order to be able to log the sender address on failure. */ | |
4427 | case ENV_MAIL_OPT_SIZE: | |
d27f98fe | 4428 | if (((size = Ustrtoul(value, &end, 10)), *end == 0)) |
059ec3d9 | 4429 | { |
d27f98fe TL |
4430 | if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX) |
4431 | size = INT_MAX; | |
4432 | message_size = (int)size; | |
059ec3d9 PH |
4433 | } |
4434 | else | |
d27f98fe TL |
4435 | arg_error = TRUE; |
4436 | break; | |
059ec3d9 | 4437 | |
d27f98fe TL |
4438 | /* If this session was initiated with EHLO and accept_8bitmime is set, |
4439 | Exim will have indicated that it supports the BODY=8BITMIME option. In | |
4440 | fact, it does not support this according to the RFCs, in that it does not | |
4441 | take any special action for forwarding messages containing 8-bit | |
4442 | characters. That is why accept_8bitmime is not the default setting, but | |
4443 | some sites want the action that is provided. We recognize both "8BITMIME" | |
4444 | and "7BIT" as body types, but take no action. */ | |
4445 | case ENV_MAIL_OPT_BODY: | |
3c0a92dc | 4446 | if (accept_8bitmime) { |
9d4319df | 4447 | if (strcmpic(value, US"8BITMIME") == 0) |
3c0a92dc | 4448 | body_8bitmime = 8; |
9d4319df | 4449 | else if (strcmpic(value, US"7BIT") == 0) |
3c0a92dc | 4450 | body_8bitmime = 7; |
9d4319df JH |
4451 | else |
4452 | { | |
3c0a92dc JH |
4453 | body_8bitmime = 0; |
4454 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4455 | US"invalid data for BODY"); | |
4456 | goto COMMAND_LOOP; | |
9d4319df | 4457 | } |
3c0a92dc JH |
4458 | DEBUG(D_receive) debug_printf("8BITMIME: %d\n", body_8bitmime); |
4459 | break; | |
4460 | } | |
d27f98fe TL |
4461 | arg_error = TRUE; |
4462 | break; | |
059ec3d9 | 4463 | |
6c1c3d1d WB |
4464 | /* Handle the two DSN options, but only if configured to do so (which |
4465 | will have caused "DSN" to be given in the EHLO response). The code itself | |
4466 | is included only if configured in at build time. */ | |
4467 | ||
4468 | case ENV_MAIL_OPT_RET: | |
9d4319df JH |
4469 | if (dsn_advertised) |
4470 | { | |
6c1c3d1d | 4471 | /* Check if RET has already been set */ |
9d4319df JH |
4472 | if (dsn_ret > 0) |
4473 | { | |
6c1c3d1d WB |
4474 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4475 | US"RET can be specified once only"); | |
4476 | goto COMMAND_LOOP; | |
9d4319df JH |
4477 | } |
4478 | dsn_ret = strcmpic(value, US"HDRS") == 0 | |
4479 | ? dsn_ret_hdrs | |
4480 | : strcmpic(value, US"FULL") == 0 | |
4481 | ? dsn_ret_full | |
4482 | : 0; | |
6c1c3d1d WB |
4483 | DEBUG(D_receive) debug_printf("DSN_RET: %d\n", dsn_ret); |
4484 | /* Check for invalid invalid value, and exit with error */ | |
9d4319df JH |
4485 | if (dsn_ret == 0) |
4486 | { | |
6c1c3d1d WB |
4487 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4488 | US"Value for RET is invalid"); | |
4489 | goto COMMAND_LOOP; | |
9d4319df JH |
4490 | } |
4491 | } | |
6c1c3d1d WB |
4492 | break; |
4493 | case ENV_MAIL_OPT_ENVID: | |
9d4319df JH |
4494 | if (dsn_advertised) |
4495 | { | |
6c1c3d1d | 4496 | /* Check if the dsn envid has been already set */ |
9d4319df JH |
4497 | if (dsn_envid != NULL) |
4498 | { | |
6c1c3d1d WB |
4499 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4500 | US"ENVID can be specified once only"); | |
4501 | goto COMMAND_LOOP; | |
9d4319df | 4502 | } |
6c1c3d1d WB |
4503 | dsn_envid = string_copy(value); |
4504 | DEBUG(D_receive) debug_printf("DSN_ENVID: %s\n", dsn_envid); | |
9d4319df | 4505 | } |
6c1c3d1d | 4506 | break; |
6c1c3d1d | 4507 | |
d27f98fe TL |
4508 | /* Handle the AUTH extension. If the value given is not "<>" and either |
4509 | the ACL says "yes" or there is no ACL but the sending host is | |
4510 | authenticated, we set it up as the authenticated sender. However, if the | |
4511 | authenticator set a condition to be tested, we ignore AUTH on MAIL unless | |
4512 | the condition is met. The value of AUTH is an xtext, which means that +, | |
4513 | = and cntrl chars are coded in hex; however "<>" is unaffected by this | |
4514 | coding. */ | |
4515 | case ENV_MAIL_OPT_AUTH: | |
4516 | if (Ustrcmp(value, "<>") != 0) | |
4517 | { | |
4518 | int rc; | |
4519 | uschar *ignore_msg; | |
059ec3d9 | 4520 | |
d27f98fe TL |
4521 | if (auth_xtextdecode(value, &authenticated_sender) < 0) |
4522 | { | |
4523 | /* Put back terminator overrides for error message */ | |
d27f98fe | 4524 | value[-1] = '='; |
fd98a5c6 | 4525 | name[-1] = ' '; |
d27f98fe TL |
4526 | done = synprot_error(L_smtp_syntax_error, 501, NULL, |
4527 | US"invalid data for AUTH"); | |
4528 | goto COMMAND_LOOP; | |
4529 | } | |
4530 | if (acl_smtp_mailauth == NULL) | |
4531 | { | |
4532 | ignore_msg = US"client not authenticated"; | |
4533 | rc = (sender_host_authenticated != NULL)? OK : FAIL; | |
4534 | } | |
4535 | else | |
4536 | { | |
4537 | ignore_msg = US"rejected by ACL"; | |
4538 | rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth, | |
4539 | &user_msg, &log_msg); | |
4540 | } | |
94431adb | 4541 | |
d27f98fe TL |
4542 | switch (rc) |
4543 | { | |
4544 | case OK: | |
9d4319df JH |
4545 | if (authenticated_by == NULL || |
4546 | authenticated_by->mail_auth_condition == NULL || | |
4547 | expand_check_condition(authenticated_by->mail_auth_condition, | |
4548 | authenticated_by->name, US"authenticator")) | |
4549 | break; /* Accept the AUTH */ | |
94431adb | 4550 | |
9d4319df JH |
4551 | ignore_msg = US"server_mail_auth_condition failed"; |
4552 | if (authenticated_id != NULL) | |
4553 | ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"", | |
4554 | ignore_msg, authenticated_id); | |
94431adb | 4555 | |
d27f98fe | 4556 | /* Fall through */ |
94431adb | 4557 | |
d27f98fe | 4558 | case FAIL: |
9d4319df JH |
4559 | authenticated_sender = NULL; |
4560 | log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)", | |
4561 | value, host_and_ident(TRUE), ignore_msg); | |
4562 | break; | |
94431adb | 4563 | |
d27f98fe TL |
4564 | /* Should only get DEFER or ERROR here. Put back terminator |
4565 | overrides for error message */ | |
94431adb | 4566 | |
d27f98fe | 4567 | default: |
9d4319df JH |
4568 | value[-1] = '='; |
4569 | name[-1] = ' '; | |
4570 | (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg, | |
4571 | log_msg); | |
4572 | goto COMMAND_LOOP; | |
d27f98fe | 4573 | } |
059ec3d9 | 4574 | } |
d27f98fe | 4575 | break; |
fd98a5c6 | 4576 | |
8ccd00b1 | 4577 | #ifndef DISABLE_PRDR |
fd98a5c6 | 4578 | case ENV_MAIL_OPT_PRDR: |
8ccd00b1 | 4579 | if (prdr_enable) |
fd98a5c6 JH |
4580 | prdr_requested = TRUE; |
4581 | break; | |
4582 | #endif | |
4583 | ||
8c5d388a | 4584 | #ifdef SUPPORT_I18N |
d1a13eea JH |
4585 | case ENV_MAIL_OPT_UTF8: |
4586 | if (smtputf8_advertised) | |
e524074d | 4587 | { |
90341c71 JH |
4588 | int old_pool = store_pool; |
4589 | ||
e524074d | 4590 | DEBUG(D_receive) debug_printf("smtputf8 requested\n"); |
9d4319df | 4591 | message_smtputf8 = allow_utf8_domains = TRUE; |
90341c71 | 4592 | store_pool = POOL_PERM; |
5a886ce7 | 4593 | received_protocol = string_sprintf("utf8%s", received_protocol); |
90341c71 | 4594 | store_pool = old_pool; |
e524074d | 4595 | } |
d1a13eea JH |
4596 | break; |
4597 | #endif | |
2ef7ed08 | 4598 | /* No valid option. Stick back the terminator characters and break |
fd98a5c6 | 4599 | the loop. Do the name-terminator second as extract_option sets |
2ef7ed08 HSHR |
4600 | value==name when it found no equal-sign. |
4601 | An error for a malformed address will occur. */ | |
4602 | case ENV_MAIL_OPT_NULL: | |
d27f98fe | 4603 | value[-1] = '='; |
fd98a5c6 JH |
4604 | name[-1] = ' '; |
4605 | arg_error = TRUE; | |
d27f98fe | 4606 | break; |
2ef7ed08 HSHR |
4607 | |
4608 | default: assert(0); | |
059ec3d9 | 4609 | } |
d27f98fe TL |
4610 | /* Break out of for loop if switch() had bad argument or |
4611 | when start of the email address is reached */ | |
4612 | if (arg_error) break; | |
059ec3d9 PH |
4613 | } |
4614 | ||
4615 | /* If we have passed the threshold for rate limiting, apply the current | |
4616 | delay, and update it for next time, provided this is a limited host. */ | |
4617 | ||
4618 | if (smtp_mailcmd_count > smtp_rlm_threshold && | |
4619 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
4620 | { | |
4621 | DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n", | |
4622 | smtp_delay_mail/1000.0); | |
4623 | millisleep((int)smtp_delay_mail); | |
4624 | smtp_delay_mail *= smtp_rlm_factor; | |
4625 | if (smtp_delay_mail > (double)smtp_rlm_limit) | |
4626 | smtp_delay_mail = (double)smtp_rlm_limit; | |
4627 | } | |
4628 | ||
4629 | /* Now extract the address, first applying any SMTP-time rewriting. The | |
4630 | TRUE flag allows "<>" as a sender address. */ | |
4631 | ||
9d4319df JH |
4632 | raw_sender = rewrite_existflags & rewrite_smtp |
4633 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
4634 | global_rewrite_rules) | |
4635 | : smtp_cmd_data; | |
059ec3d9 | 4636 | |
059ec3d9 PH |
4637 | raw_sender = |
4638 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
4639 | TRUE); | |
059ec3d9 | 4640 | |
2685d6e0 | 4641 | if (!raw_sender) |
059ec3d9 | 4642 | { |
ca86f471 | 4643 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); |
059ec3d9 PH |
4644 | break; |
4645 | } | |
4646 | ||
4647 | sender_address = raw_sender; | |
4648 | ||
4649 | /* If there is a configured size limit for mail, check that this message | |
4650 | doesn't exceed it. The check is postponed to this point so that the sender | |
4651 | can be logged. */ | |
4652 | ||
4653 | if (thismessage_size_limit > 0 && message_size > thismessage_size_limit) | |
4654 | { | |
925ac8e4 | 4655 | smtp_printf("552 Message size exceeds maximum permitted\r\n", FALSE); |
059ec3d9 PH |
4656 | log_write(L_size_reject, |
4657 | LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: " | |
4658 | "message too big: size%s=%d max=%d", | |
4659 | sender_address, | |
4660 | host_and_ident(TRUE), | |
4661 | (message_size == INT_MAX)? ">" : "", | |
4662 | message_size, | |
4663 | thismessage_size_limit); | |
4664 | sender_address = NULL; | |
4665 | break; | |
4666 | } | |
4667 | ||
4668 | /* Check there is enough space on the disk unless configured not to. | |
4669 | When smtp_check_spool_space is set, the check is for thismessage_size_limit | |
4670 | plus the current message - i.e. we accept the message only if it won't | |
4671 | reduce the space below the threshold. Add 5000 to the size to allow for | |
4672 | overheads such as the Received: line and storing of recipients, etc. | |
4673 | By putting the check here, even when SIZE is not given, it allow VRFY | |
4674 | and EXPN etc. to be used when space is short. */ | |
4675 | ||
4676 | if (!receive_check_fs( | |
4677 | (smtp_check_spool_space && message_size >= 0)? | |
4678 | message_size + 5000 : 0)) | |
4679 | { | |
925ac8e4 | 4680 | smtp_printf("452 Space shortage, please try later\r\n", FALSE); |
059ec3d9 PH |
4681 | sender_address = NULL; |
4682 | break; | |
4683 | } | |
4684 | ||
4685 | /* If sender_address is unqualified, reject it, unless this is a locally | |
4686 | generated message, or the sending host or net is permitted to send | |
4687 | unqualified addresses - typically local machines behaving as MUAs - | |
4688 | in which case just qualify the address. The flag is set above at the start | |
4689 | of the SMTP connection. */ | |
4690 | ||
4691 | if (sender_domain == 0 && sender_address[0] != 0) | |
4692 | { | |
4693 | if (allow_unqualified_sender) | |
4694 | { | |
4695 | sender_domain = Ustrlen(sender_address) + 1; | |
4696 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
4697 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
4698 | raw_sender); | |
4699 | } | |
4700 | else | |
4701 | { | |
925ac8e4 | 4702 | smtp_printf("501 %s: sender address must contain a domain\r\n", FALSE, |
ca86f471 | 4703 | smtp_cmd_data); |
059ec3d9 PH |
4704 | log_write(L_smtp_syntax_error, |
4705 | LOG_MAIN|LOG_REJECT, | |
4706 | "unqualified sender rejected: <%s> %s%s", | |
4707 | raw_sender, | |
4708 | host_and_ident(TRUE), | |
4709 | host_lookup_msg); | |
4710 | sender_address = NULL; | |
4711 | break; | |
4712 | } | |
4713 | } | |
4714 | ||
a14e5636 PH |
4715 | /* Apply an ACL check if one is defined, before responding. Afterwards, |
4716 | when pipelining is not advertised, do another sync check in case the ACL | |
4717 | delayed and the client started sending in the meantime. */ | |
059ec3d9 | 4718 | |
8ccd00b1 | 4719 | if (acl_smtp_mail) |
a14e5636 PH |
4720 | { |
4721 | rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg); | |
4722 | if (rc == OK && !pipelining_advertised && !check_sync()) | |
4723 | goto SYNC_FAILURE; | |
4724 | } | |
8ccd00b1 JH |
4725 | else |
4726 | rc = OK; | |
059ec3d9 PH |
4727 | |
4728 | if (rc == OK || rc == DISCARD) | |
4729 | { | |
925ac8e4 JH |
4730 | BOOL more = pipeline_response(); |
4731 | ||
8ccd00b1 | 4732 | if (!user_msg) |
925ac8e4 | 4733 | smtp_printf("%s%s%s", more, US"250 OK", |
8ccd00b1 JH |
4734 | #ifndef DISABLE_PRDR |
4735 | prdr_requested ? US", PRDR Requested" : US"", | |
4736 | #else | |
fd98a5c6 | 4737 | US"", |
8ccd00b1 | 4738 | #endif |
fd98a5c6 | 4739 | US"\r\n"); |
94431adb | 4740 | else |
fd98a5c6 | 4741 | { |
8ccd00b1 JH |
4742 | #ifndef DISABLE_PRDR |
4743 | if (prdr_requested) | |
fd98a5c6 JH |
4744 | user_msg = string_sprintf("%s%s", user_msg, US", PRDR Requested"); |
4745 | #endif | |
8ccd00b1 | 4746 | smtp_user_msg(US"250", user_msg); |
fd98a5c6 | 4747 | } |
059ec3d9 PH |
4748 | smtp_delay_rcpt = smtp_rlr_base; |
4749 | recipients_discarded = (rc == DISCARD); | |
4750 | was_rej_mail = FALSE; | |
4751 | } | |
059ec3d9 PH |
4752 | else |
4753 | { | |
4754 | done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg); | |
4755 | sender_address = NULL; | |
4756 | } | |
4757 | break; | |
4758 | ||
4759 | ||
2679d413 PH |
4760 | /* The RCPT command requires an address as an operand. There may be any |
4761 | number of RCPT commands, specifying multiple recipients. We build them all | |
4762 | into a data structure. The start/end values given by parse_extract_address | |
4763 | are not used, as we keep only the extracted address. */ | |
059ec3d9 PH |
4764 | |
4765 | case RCPT_CMD: | |
b4ed4da0 | 4766 | HAD(SCH_RCPT); |
059ec3d9 | 4767 | rcpt_count++; |
2679d413 | 4768 | was_rcpt = rcpt_in_progress = TRUE; |
059ec3d9 PH |
4769 | |
4770 | /* There must be a sender address; if the sender was rejected and | |
4771 | pipelining was advertised, we assume the client was pipelining, and do not | |
4772 | count this as a protocol error. Reset was_rej_mail so that further RCPTs | |
4773 | get the same treatment. */ | |
4774 | ||
4775 | if (sender_address == NULL) | |
4776 | { | |
4777 | if (pipelining_advertised && last_was_rej_mail) | |
4778 | { | |
925ac8e4 | 4779 | smtp_printf("503 sender not yet given\r\n", FALSE); |
059ec3d9 PH |
4780 | was_rej_mail = TRUE; |
4781 | } | |
4782 | else | |
4783 | { | |
4784 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4785 | US"sender not yet given"); | |
4786 | was_rcpt = FALSE; /* Not a valid RCPT */ | |
4787 | } | |
4788 | rcpt_fail_count++; | |
4789 | break; | |
4790 | } | |
4791 | ||
4792 | /* Check for an operand */ | |
4793 | ||
ca86f471 | 4794 | if (smtp_cmd_data[0] == 0) |
059ec3d9 PH |
4795 | { |
4796 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4797 | US"RCPT must have an address operand"); | |
4798 | rcpt_fail_count++; | |
4799 | break; | |
4800 | } | |
50dc7409 | 4801 | |
6c1c3d1d WB |
4802 | /* Set the DSN flags orcpt and dsn_flags from the session*/ |
4803 | orcpt = NULL; | |
4804 | flags = 0; | |
4805 | ||
4806 | if (esmtp) for(;;) | |
4807 | { | |
45500060 | 4808 | uschar *name, *value; |
6c1c3d1d WB |
4809 | |
4810 | if (!extract_option(&name, &value)) | |
6c1c3d1d | 4811 | break; |
6c1c3d1d WB |
4812 | |
4813 | if (dsn_advertised && strcmpic(name, US"ORCPT") == 0) | |
4814 | { | |
4815 | /* Check whether orcpt has been already set */ | |
45500060 JH |
4816 | if (orcpt) |
4817 | { | |
6c1c3d1d WB |
4818 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4819 | US"ORCPT can be specified once only"); | |
4820 | goto COMMAND_LOOP; | |
4821 | } | |
4822 | orcpt = string_copy(value); | |
4823 | DEBUG(D_receive) debug_printf("DSN orcpt: %s\n", orcpt); | |
4824 | } | |
4825 | ||
4826 | else if (dsn_advertised && strcmpic(name, US"NOTIFY") == 0) | |
4827 | { | |
4828 | /* Check if the notify flags have been already set */ | |
45500060 JH |
4829 | if (flags > 0) |
4830 | { | |
6c1c3d1d WB |
4831 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4832 | US"NOTIFY can be specified once only"); | |
4833 | goto COMMAND_LOOP; | |
4834 | } | |
45500060 JH |
4835 | if (strcmpic(value, US"NEVER") == 0) |
4836 | flags |= rf_notify_never; | |
4837 | else | |
6c1c3d1d WB |
4838 | { |
4839 | uschar *p = value; | |
4840 | while (*p != 0) | |
4841 | { | |
4842 | uschar *pp = p; | |
4843 | while (*pp != 0 && *pp != ',') pp++; | |
45500060 JH |
4844 | if (*pp == ',') *pp++ = 0; |
4845 | if (strcmpic(p, US"SUCCESS") == 0) | |
4846 | { | |
4847 | DEBUG(D_receive) debug_printf("DSN: Setting notify success\n"); | |
4848 | flags |= rf_notify_success; | |
6c1c3d1d | 4849 | } |
45500060 JH |
4850 | else if (strcmpic(p, US"FAILURE") == 0) |
4851 | { | |
4852 | DEBUG(D_receive) debug_printf("DSN: Setting notify failure\n"); | |
4853 | flags |= rf_notify_failure; | |
6c1c3d1d | 4854 | } |
45500060 JH |
4855 | else if (strcmpic(p, US"DELAY") == 0) |
4856 | { | |
4857 | DEBUG(D_receive) debug_printf("DSN: Setting notify delay\n"); | |
4858 | flags |= rf_notify_delay; | |
6c1c3d1d | 4859 | } |
45500060 JH |
4860 | else |
4861 | { | |
6c1c3d1d WB |
4862 | /* Catch any strange values */ |
4863 | synprot_error(L_smtp_syntax_error, 501, NULL, | |
4864 | US"Invalid value for NOTIFY parameter"); | |
4865 | goto COMMAND_LOOP; | |
4866 | } | |
4867 | p = pp; | |
4868 | } | |
4869 | DEBUG(D_receive) debug_printf("DSN Flags: %x\n", flags); | |
4870 | } | |
4871 | } | |
4872 | ||
4873 | /* Unknown option. Stick back the terminator characters and break | |
4874 | the loop. An error for a malformed address will occur. */ | |
4875 | ||
4876 | else | |
4877 | { | |
4878 | DEBUG(D_receive) debug_printf("Invalid RCPT option: %s : %s\n", name, value); | |
4879 | name[-1] = ' '; | |
4880 | value[-1] = '='; | |
4881 | break; | |
4882 | } | |
4883 | } | |
059ec3d9 PH |
4884 | |
4885 | /* Apply SMTP rewriting then extract the working address. Don't allow "<>" | |
4886 | as a recipient address */ | |
4887 | ||
05392bbc JH |
4888 | recipient = rewrite_existflags & rewrite_smtp |
4889 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
4890 | global_rewrite_rules) | |
4891 | : smtp_cmd_data; | |
059ec3d9 | 4892 | |
2685d6e0 JH |
4893 | if (!(recipient = parse_extract_address(recipient, &errmess, &start, &end, |
4894 | &recipient_domain, FALSE))) | |
059ec3d9 | 4895 | { |
ca86f471 | 4896 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); |
059ec3d9 PH |
4897 | rcpt_fail_count++; |
4898 | break; | |
4899 | } | |
4900 | ||
4901 | /* If the recipient address is unqualified, reject it, unless this is a | |
4902 | locally generated message. However, unqualified addresses are permitted | |
4903 | from a configured list of hosts and nets - typically when behaving as | |
4904 | MUAs rather than MTAs. Sad that SMTP is used for both types of traffic, | |
4905 | really. The flag is set at the start of the SMTP connection. | |
4906 | ||
4907 | RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always | |
4908 | assumed this meant "reserved local part", but the revision of RFC 821 and | |
4909 | friends now makes it absolutely clear that it means *mailbox*. Consequently | |
4910 | we must always qualify this address, regardless. */ | |
4911 | ||
c39b93a6 | 4912 | if (!recipient_domain) |
2685d6e0 JH |
4913 | if (!(recipient_domain = qualify_recipient(&recipient, smtp_cmd_data, |
4914 | US"recipient"))) | |
059ec3d9 PH |
4915 | { |
4916 | rcpt_fail_count++; | |
059ec3d9 PH |
4917 | break; |
4918 | } | |
059ec3d9 PH |
4919 | |
4920 | /* Check maximum allowed */ | |
4921 | ||
4922 | if (rcpt_count > recipients_max && recipients_max > 0) | |
4923 | { | |
4924 | if (recipients_max_reject) | |
4925 | { | |
4926 | rcpt_fail_count++; | |
925ac8e4 | 4927 | smtp_printf("552 too many recipients\r\n", FALSE); |
059ec3d9 PH |
4928 | if (!toomany) |
4929 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message " | |
4930 | "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE)); | |
4931 | } | |
4932 | else | |
4933 | { | |
4934 | rcpt_defer_count++; | |
925ac8e4 | 4935 | smtp_printf("452 too many recipients\r\n", FALSE); |
059ec3d9 PH |
4936 | if (!toomany) |
4937 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess " | |
4938 | "temporarily rejected: sender=<%s> %s", sender_address, | |
4939 | host_and_ident(TRUE)); | |
4940 | } | |
4941 | ||
4942 | toomany = TRUE; | |
4943 | break; | |
4944 | } | |
4945 | ||
4946 | /* If we have passed the threshold for rate limiting, apply the current | |
4947 | delay, and update it for next time, provided this is a limited host. */ | |
4948 | ||
4949 | if (rcpt_count > smtp_rlr_threshold && | |
4950 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
4951 | { | |
4952 | DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n", | |
4953 | smtp_delay_rcpt/1000.0); | |
4954 | millisleep((int)smtp_delay_rcpt); | |
4955 | smtp_delay_rcpt *= smtp_rlr_factor; | |
4956 | if (smtp_delay_rcpt > (double)smtp_rlr_limit) | |
4957 | smtp_delay_rcpt = (double)smtp_rlr_limit; | |
4958 | } | |
4959 | ||
4960 | /* If the MAIL ACL discarded all the recipients, we bypass ACL checking | |
a14e5636 PH |
4961 | for them. Otherwise, check the access control list for this recipient. As |
4962 | there may be a delay in this, re-check for a synchronization error | |
4963 | afterwards, unless pipelining was advertised. */ | |
059ec3d9 | 4964 | |
a23ff3b4 JH |
4965 | if (recipients_discarded) |
4966 | rc = DISCARD; | |
4967 | else | |
4968 | if ( (rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg, | |
4969 | &log_msg)) == OK | |
4970 | && !pipelining_advertised && !check_sync()) | |
a14e5636 | 4971 | goto SYNC_FAILURE; |
059ec3d9 PH |
4972 | |
4973 | /* The ACL was happy */ | |
4974 | ||
4975 | if (rc == OK) | |
4976 | { | |
925ac8e4 JH |
4977 | BOOL more = pipeline_response(); |
4978 | ||
a23ff3b4 JH |
4979 | if (user_msg) |
4980 | smtp_user_msg(US"250", user_msg); | |
4981 | else | |
925ac8e4 | 4982 | smtp_printf("250 Accepted\r\n", more); |
059ec3d9 | 4983 | receive_add_recipient(recipient, -1); |
94431adb | 4984 | |
6c1c3d1d | 4985 | /* Set the dsn flags in the recipients_list */ |
7ade712c JH |
4986 | recipients_list[recipients_count-1].orcpt = orcpt; |
4987 | recipients_list[recipients_count-1].dsn_flags = flags; | |
6c1c3d1d | 4988 | |
7ade712c JH |
4989 | DEBUG(D_receive) debug_printf("DSN: orcpt: %s flags: %d\n", |
4990 | recipients_list[recipients_count-1].orcpt, | |
4991 | recipients_list[recipients_count-1].dsn_flags); | |
059ec3d9 PH |
4992 | } |
4993 | ||
4994 | /* The recipient was discarded */ | |
4995 | ||
4996 | else if (rc == DISCARD) | |
4997 | { | |
a23ff3b4 JH |
4998 | if (user_msg) |
4999 | smtp_user_msg(US"250", user_msg); | |
5000 | else | |
925ac8e4 | 5001 | smtp_printf("250 Accepted\r\n", FALSE); |
059ec3d9 PH |
5002 | rcpt_fail_count++; |
5003 | discarded = TRUE; | |
1f12df4d | 5004 | log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> RCPT %s: " |
059ec3d9 | 5005 | "discarded by %s ACL%s%s", host_and_ident(TRUE), |
1f12df4d | 5006 | sender_address_unrewritten? sender_address_unrewritten : sender_address, |
3ee512ff | 5007 | smtp_cmd_argument, recipients_discarded? "MAIL" : "RCPT", |
1f12df4d | 5008 | log_msg ? US": " : US"", log_msg ? log_msg : US""); |
059ec3d9 PH |
5009 | } |
5010 | ||
5011 | /* Either the ACL failed the address, or it was deferred. */ | |
5012 | ||
5013 | else | |
5014 | { | |
5015 | if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++; | |
5016 | done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg); | |
5017 | } | |
5018 | break; | |
5019 | ||
5020 | ||
5021 | /* The DATA command is legal only if it follows successful MAIL FROM | |
5022 | and RCPT TO commands. However, if pipelining is advertised, a bad DATA is | |
5023 | not counted as a protocol error if it follows RCPT (which must have been | |
5024 | rejected if there are no recipients.) This function is complete when a | |
5025 | valid DATA command is encountered. | |
5026 | ||
5027 | Note concerning the code used: RFC 2821 says this: | |
5028 | ||
5029 | - If there was no MAIL, or no RCPT, command, or all such commands | |
5030 | were rejected, the server MAY return a "command out of sequence" | |
5031 | (503) or "no valid recipients" (554) reply in response to the | |
5032 | DATA command. | |
5033 | ||
5034 | The example in the pipelining RFC 2920 uses 554, but I use 503 here | |
2679d413 PH |
5035 | because it is the same whether pipelining is in use or not. |
5036 | ||
5037 | If all the RCPT commands that precede DATA provoked the same error message | |
5038 | (often indicating some kind of system error), it is helpful to include it | |
5039 | with the DATA rejection (an idea suggested by Tony Finch). */ | |
059ec3d9 | 5040 | |
18481de3 JH |
5041 | case BDAT_CMD: |
5042 | HAD(SCH_BDAT); | |
5043 | { | |
5044 | int n; | |
5045 | ||
5046 | if (chunking_state != CHUNKING_OFFERED) | |
5047 | { | |
5048 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5049 | US"BDAT command used when CHUNKING not advertised"); | |
5050 | break; | |
5051 | } | |
5052 | ||
5053 | /* grab size, endmarker */ | |
5054 | ||
5055 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) | |
5056 | { | |
7e3ce68e | 5057 | done = synprot_error(L_smtp_protocol_error, 501, NULL, |
18481de3 JH |
5058 | US"missing size for BDAT command"); |
5059 | break; | |
5060 | } | |
5061 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
5062 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
7e3ce68e | 5063 | chunking_data_left = chunking_datasize; |
bd8fbe36 JH |
5064 | DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n", |
5065 | (int)chunking_state, chunking_data_left); | |
7e3ce68e JH |
5066 | |
5067 | lwr_receive_getc = receive_getc; | |
0d81dabc | 5068 | lwr_receive_getbuf = receive_getbuf; |
7e3ce68e JH |
5069 | lwr_receive_ungetc = receive_ungetc; |
5070 | receive_getc = bdat_getc; | |
5071 | receive_ungetc = bdat_ungetc; | |
18481de3 | 5072 | |
18481de3 JH |
5073 | goto DATA_BDAT; |
5074 | } | |
5075 | ||
059ec3d9 | 5076 | case DATA_CMD: |
b4ed4da0 | 5077 | HAD(SCH_DATA); |
18481de3 JH |
5078 | |
5079 | DATA_BDAT: /* Common code for DATA and BDAT */ | |
059ec3d9 PH |
5080 | if (!discarded && recipients_count <= 0) |
5081 | { | |
2679d413 PH |
5082 | if (rcpt_smtp_response_same && rcpt_smtp_response != NULL) |
5083 | { | |
5084 | uschar *code = US"503"; | |
5085 | int len = Ustrlen(rcpt_smtp_response); | |
5086 | smtp_respond(code, 3, FALSE, US"All RCPT commands were rejected with " | |
5087 | "this error:"); | |
5088 | /* Responses from smtp_printf() will have \r\n on the end */ | |
5089 | if (len > 2 && rcpt_smtp_response[len-2] == '\r') | |
5090 | rcpt_smtp_response[len-2] = 0; | |
5091 | smtp_respond(code, 3, FALSE, rcpt_smtp_response); | |
5092 | } | |
059ec3d9 | 5093 | if (pipelining_advertised && last_was_rcpt) |
925ac8e4 | 5094 | smtp_printf("503 Valid RCPT command must precede %s\r\n", FALSE, |
18481de3 | 5095 | smtp_names[smtp_connection_had[smtp_ch_index-1]]); |
059ec3d9 PH |
5096 | else |
5097 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
18481de3 JH |
5098 | smtp_connection_had[smtp_ch_index-1] == SCH_DATA |
5099 | ? US"valid RCPT command must precede DATA" | |
5100 | : US"valid RCPT command must precede BDAT"); | |
45bd315d JH |
5101 | |
5102 | if (chunking_state > CHUNKING_OFFERED) | |
5103 | bdat_flush_data(); | |
059ec3d9 PH |
5104 | break; |
5105 | } | |
5106 | ||
5107 | if (toomany && recipients_max_reject) | |
5108 | { | |
5109 | sender_address = NULL; /* This will allow a new MAIL without RSET */ | |
5110 | sender_address_unrewritten = NULL; | |
925ac8e4 | 5111 | smtp_printf("554 Too many recipients\r\n", FALSE); |
059ec3d9 PH |
5112 | break; |
5113 | } | |
8e669ac1 | 5114 | |
7e3ce68e | 5115 | if (chunking_state > CHUNKING_OFFERED) |
a23ff3b4 | 5116 | rc = OK; /* No predata ACL or go-ahead output for BDAT */ |
18481de3 | 5117 | else |
8e669ac1 | 5118 | { |
7e3ce68e JH |
5119 | /* If there is an ACL, re-check the synchronization afterwards, since the |
5120 | ACL may have delayed. To handle cutthrough delivery enforce a dummy call | |
5121 | to get the DATA command sent. */ | |
059ec3d9 | 5122 | |
7e3ce68e JH |
5123 | if (acl_smtp_predata == NULL && cutthrough.fd < 0) |
5124 | rc = OK; | |
5125 | else | |
5126 | { | |
5127 | uschar * acl = acl_smtp_predata ? acl_smtp_predata : US"accept"; | |
5128 | enable_dollar_recipients = TRUE; | |
5129 | rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg, | |
5130 | &log_msg); | |
5131 | enable_dollar_recipients = FALSE; | |
5132 | if (rc == OK && !check_sync()) | |
5133 | goto SYNC_FAILURE; | |
5134 | ||
5135 | if (rc != OK) | |
5136 | { /* Either the ACL failed the address, or it was deferred. */ | |
5137 | done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg); | |
5138 | break; | |
5139 | } | |
5140 | } | |
5141 | ||
5142 | if (user_msg) | |
5143 | smtp_user_msg(US"354", user_msg); | |
5144 | else | |
5145 | smtp_printf( | |
925ac8e4 | 5146 | "354 Enter message, ending with \".\" on a line by itself\r\n", FALSE); |
059ec3d9 PH |
5147 | } |
5148 | ||
8d330698 JH |
5149 | #ifdef TCP_QUICKACK |
5150 | if (smtp_in) /* all ACKs needed to ramp window up for bulk data */ | |
5151 | (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK, | |
5152 | US &on, sizeof(on)); | |
5153 | #endif | |
7e3ce68e JH |
5154 | done = 3; |
5155 | message_ended = END_NOTENDED; /* Indicate in middle of data */ | |
059ec3d9 | 5156 | |
059ec3d9 PH |
5157 | break; |
5158 | ||
5159 | ||
5160 | case VRFY_CMD: | |
059ec3d9 | 5161 | { |
4f6ae5c3 | 5162 | uschar * address; |
059ec3d9 | 5163 | |
4f6ae5c3 | 5164 | HAD(SCH_VRFY); |
059ec3d9 | 5165 | |
05392bbc JH |
5166 | if (!(address = parse_extract_address(smtp_cmd_data, &errmess, |
5167 | &start, &end, &recipient_domain, FALSE))) | |
5168 | { | |
925ac8e4 | 5169 | smtp_printf("501 %s\r\n", FALSE, errmess); |
05392bbc JH |
5170 | break; |
5171 | } | |
5172 | ||
c39b93a6 | 5173 | if (!recipient_domain) |
2685d6e0 JH |
5174 | if (!(recipient_domain = qualify_recipient(&address, smtp_cmd_data, |
5175 | US"verify"))) | |
05392bbc | 5176 | break; |
4f6ae5c3 | 5177 | |
05392bbc | 5178 | if ((rc = acl_check(ACL_WHERE_VRFY, address, acl_smtp_vrfy, |
4f6ae5c3 JH |
5179 | &user_msg, &log_msg)) != OK) |
5180 | done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg); | |
059ec3d9 | 5181 | else |
4f6ae5c3 | 5182 | { |
05392bbc JH |
5183 | uschar * s = NULL; |
5184 | address_item * addr = deliver_make_addr(address, FALSE); | |
059ec3d9 | 5185 | |
4f6ae5c3 JH |
5186 | switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1, |
5187 | -1, -1, NULL, NULL, NULL)) | |
5188 | { | |
5189 | case OK: | |
5190 | s = string_sprintf("250 <%s> is deliverable", address); | |
5191 | break; | |
059ec3d9 | 5192 | |
4f6ae5c3 JH |
5193 | case DEFER: |
5194 | s = (addr->user_message != NULL)? | |
5195 | string_sprintf("451 <%s> %s", address, addr->user_message) : | |
5196 | string_sprintf("451 Cannot resolve <%s> at this time", address); | |
5197 | break; | |
059ec3d9 | 5198 | |
4f6ae5c3 JH |
5199 | case FAIL: |
5200 | s = (addr->user_message != NULL)? | |
5201 | string_sprintf("550 <%s> %s", address, addr->user_message) : | |
5202 | string_sprintf("550 <%s> is not deliverable", address); | |
5203 | log_write(0, LOG_MAIN, "VRFY failed for %s %s", | |
5204 | smtp_cmd_argument, host_and_ident(TRUE)); | |
5205 | break; | |
5206 | } | |
5207 | ||
925ac8e4 | 5208 | smtp_printf("%s\r\n", FALSE, s); |
4f6ae5c3 JH |
5209 | } |
5210 | break; | |
059ec3d9 | 5211 | } |
059ec3d9 PH |
5212 | |
5213 | ||
5214 | case EXPN_CMD: | |
b4ed4da0 | 5215 | HAD(SCH_EXPN); |
64ffc24f | 5216 | rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg); |
059ec3d9 PH |
5217 | if (rc != OK) |
5218 | done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg); | |
5219 | else | |
5220 | { | |
5221 | BOOL save_log_testing_mode = log_testing_mode; | |
5222 | address_test_mode = log_testing_mode = TRUE; | |
ca86f471 | 5223 | (void) verify_address(deliver_make_addr(smtp_cmd_data, FALSE), |
64ffc24f PH |
5224 | smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1, |
5225 | NULL, NULL, NULL); | |
059ec3d9 PH |
5226 | address_test_mode = FALSE; |
5227 | log_testing_mode = save_log_testing_mode; /* true for -bh */ | |
5228 | } | |
5229 | break; | |
5230 | ||
5231 | ||
5232 | #ifdef SUPPORT_TLS | |
5233 | ||
5234 | case STARTTLS_CMD: | |
b4ed4da0 | 5235 | HAD(SCH_STARTTLS); |
059ec3d9 PH |
5236 | if (!tls_advertised) |
5237 | { | |
5238 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5239 | US"STARTTLS command used when not advertised"); | |
5240 | break; | |
5241 | } | |
5242 | ||
5243 | /* Apply an ACL check if one is defined */ | |
5244 | ||
4f6ae5c3 JH |
5245 | if ( acl_smtp_starttls |
5246 | && (rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls, | |
5247 | &user_msg, &log_msg)) != OK | |
5248 | ) | |
059ec3d9 | 5249 | { |
4f6ae5c3 JH |
5250 | done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg); |
5251 | break; | |
059ec3d9 PH |
5252 | } |
5253 | ||
5254 | /* RFC 2487 is not clear on when this command may be sent, though it | |
5255 | does state that all information previously obtained from the client | |
4c04137d | 5256 | must be discarded if a TLS session is started. It seems reasonable to |
059ec3d9 PH |
5257 | do an implied RSET when STARTTLS is received. */ |
5258 | ||
5259 | incomplete_transaction_log(US"STARTTLS"); | |
57cc2785 | 5260 | cancel_cutthrough_connection(TRUE, US"STARTTLS received"); |
059ec3d9 PH |
5261 | smtp_reset(reset_point); |
5262 | toomany = FALSE; | |
5263 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = FALSE; | |
5264 | ||
da80c2a8 PP |
5265 | /* There's an attack where more data is read in past the STARTTLS command |
5266 | before TLS is negotiated, then assumed to be part of the secure session | |
5267 | when used afterwards; we use segregated input buffers, so are not | |
5268 | vulnerable, but we want to note when it happens and, for sheer paranoia, | |
5269 | ensure that the buffer is "wiped". | |
5270 | Pipelining sync checks will normally have protected us too, unless disabled | |
5271 | by configuration. */ | |
5272 | ||
5273 | if (receive_smtp_buffered()) | |
5274 | { | |
5275 | DEBUG(D_any) | |
18481de3 | 5276 | debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n"); |
817d9f57 | 5277 | if (tls_in.active < 0) |
da80c2a8 PP |
5278 | smtp_inend = smtp_inptr = smtp_inbuffer; |
5279 | /* and if TLS is already active, tls_server_start() should fail */ | |
5280 | } | |
5281 | ||
4c04137d | 5282 | /* There is nothing we value in the input buffer and if TLS is successfully |
4e7ee012 PP |
5283 | negotiated, we won't use this buffer again; if TLS fails, we'll just read |
5284 | fresh content into it. The buffer contains arbitrary content from an | |
5285 | untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n | |
5286 | It seems safest to just wipe away the content rather than leave it as a | |
5287 | target to jump to. */ | |
5288 | ||
bd8fbe36 | 5289 | memset(smtp_inbuffer, 0, IN_BUFFER_SIZE); |
4e7ee012 | 5290 | |
059ec3d9 PH |
5291 | /* Attempt to start up a TLS session, and if successful, discard all |
5292 | knowledge that was obtained previously. At least, that's what the RFC says, | |
5293 | and that's what happens by default. However, in order to work round YAEB, | |
5294 | there is an option to remember the esmtp state. Sigh. | |
5295 | ||
5296 | We must allow for an extra EHLO command and an extra AUTH command after | |
5297 | STARTTLS that don't add to the nonmail command count. */ | |
5298 | ||
cf0c6164 JH |
5299 | s = NULL; |
5300 | if ((rc = tls_server_start(tls_require_ciphers, &s)) == OK) | |
059ec3d9 PH |
5301 | { |
5302 | if (!tls_remember_esmtp) | |
5303 | helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE; | |
5304 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
5305 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE; | |
b3ef41c9 | 5306 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; |
059ec3d9 PH |
5307 | if (sender_helo_name != NULL) |
5308 | { | |
5309 | store_free(sender_helo_name); | |
5310 | sender_helo_name = NULL; | |
5311 | host_build_sender_fullhost(); /* Rebuild */ | |
5312 | set_process_info("handling incoming TLS connection from %s", | |
5313 | host_and_ident(FALSE)); | |
5314 | } | |
e524074d JH |
5315 | received_protocol = |
5316 | (sender_host_address ? protocols : protocols_local) | |
5317 | [ (esmtp | |
5318 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
5319 | : pnormal) | |
5320 | + (tls_in.active >= 0 ? pcrpted : 0) | |
5321 | ]; | |
059ec3d9 PH |
5322 | |
5323 | sender_host_authenticated = NULL; | |
5324 | authenticated_id = NULL; | |
5325 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; | |
5326 | DEBUG(D_tls) debug_printf("TLS active\n"); | |
5327 | break; /* Successful STARTTLS */ | |
5328 | } | |
cf0c6164 JH |
5329 | else |
5330 | (void) smtp_log_tls_fail(s); | |
059ec3d9 PH |
5331 | |
5332 | /* Some local configuration problem was discovered before actually trying | |
5333 | to do a TLS handshake; give a temporary error. */ | |
5334 | ||
cf0c6164 | 5335 | if (rc == DEFER) |
059ec3d9 | 5336 | { |
925ac8e4 | 5337 | smtp_printf("454 TLS currently unavailable\r\n", FALSE); |
059ec3d9 PH |
5338 | break; |
5339 | } | |
5340 | ||
5341 | /* Hard failure. Reject everything except QUIT or closed connection. One | |
817d9f57 | 5342 | cause for failure is a nested STARTTLS, in which case tls_in.active remains |
059ec3d9 PH |
5343 | set, but we must still reject all incoming commands. */ |
5344 | ||
5345 | DEBUG(D_tls) debug_printf("TLS failed to start\n"); | |
bd8fbe36 | 5346 | while (done <= 0) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) |
059ec3d9 | 5347 | { |
60d10ce7 JH |
5348 | case EOF_CMD: |
5349 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF", | |
5350 | smtp_get_connection_info()); | |
5351 | smtp_notquit_exit(US"tls-failed", NULL, NULL); | |
5352 | done = 2; | |
5353 | break; | |
8f128379 | 5354 | |
60d10ce7 JH |
5355 | /* It is perhaps arguable as to which exit ACL should be called here, |
5356 | but as it is probably a situation that almost never arises, it | |
5357 | probably doesn't matter. We choose to call the real QUIT ACL, which in | |
5358 | some sense is perhaps "right". */ | |
5359 | ||
5360 | case QUIT_CMD: | |
5361 | user_msg = NULL; | |
5362 | if ( acl_smtp_quit | |
5363 | && ((rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, | |
5364 | &log_msg)) == ERROR)) | |
5365 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
5366 | log_msg); | |
5367 | if (user_msg) | |
5368 | smtp_respond(US"221", 3, TRUE, user_msg); | |
5369 | else | |
925ac8e4 | 5370 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); |
60d10ce7 JH |
5371 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", |
5372 | smtp_get_connection_info()); | |
5373 | done = 2; | |
5374 | break; | |
059ec3d9 | 5375 | |
60d10ce7 | 5376 | default: |
925ac8e4 | 5377 | smtp_printf("554 Security failure\r\n", FALSE); |
60d10ce7 | 5378 | break; |
059ec3d9 | 5379 | } |
817d9f57 | 5380 | tls_close(TRUE, TRUE); |
059ec3d9 PH |
5381 | break; |
5382 | #endif | |
5383 | ||
5384 | ||
5385 | /* The ACL for QUIT is provided for gathering statistical information or | |
5386 | similar; it does not affect the response code, but it can supply a custom | |
5387 | message. */ | |
5388 | ||
5389 | case QUIT_CMD: | |
7e3ce68e | 5390 | smtp_quit_handler(&user_msg, &log_msg); |
059ec3d9 | 5391 | done = 2; |
059ec3d9 PH |
5392 | break; |
5393 | ||
5394 | ||
5395 | case RSET_CMD: | |
7e3ce68e | 5396 | smtp_rset_handler(); |
57cc2785 | 5397 | cancel_cutthrough_connection(TRUE, US"RSET received"); |
059ec3d9 PH |
5398 | smtp_reset(reset_point); |
5399 | toomany = FALSE; | |
059ec3d9 PH |
5400 | break; |
5401 | ||
5402 | ||
5403 | case NOOP_CMD: | |
b4ed4da0 | 5404 | HAD(SCH_NOOP); |
925ac8e4 | 5405 | smtp_printf("250 OK\r\n", FALSE); |
059ec3d9 PH |
5406 | break; |
5407 | ||
5408 | ||
b43a74ea PH |
5409 | /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually |
5410 | used, a check will be done for permitted hosts. Show STARTTLS only if not | |
5411 | already in a TLS session and if it would be advertised in the EHLO | |
5412 | response. */ | |
059ec3d9 PH |
5413 | |
5414 | case HELP_CMD: | |
b4ed4da0 | 5415 | HAD(SCH_HELP); |
925ac8e4 | 5416 | smtp_printf("214-Commands supported:\r\n", TRUE); |
059ec3d9 PH |
5417 | { |
5418 | uschar buffer[256]; | |
5419 | buffer[0] = 0; | |
5420 | Ustrcat(buffer, " AUTH"); | |
5421 | #ifdef SUPPORT_TLS | |
817d9f57 | 5422 | if (tls_in.active < 0 && |
b43a74ea PH |
5423 | verify_check_host(&tls_advertise_hosts) != FAIL) |
5424 | Ustrcat(buffer, " STARTTLS"); | |
059ec3d9 | 5425 | #endif |
7e3ce68e | 5426 | Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA BDAT"); |
059ec3d9 PH |
5427 | Ustrcat(buffer, " NOOP QUIT RSET HELP"); |
5428 | if (acl_smtp_etrn != NULL) Ustrcat(buffer, " ETRN"); | |
5429 | if (acl_smtp_expn != NULL) Ustrcat(buffer, " EXPN"); | |
5430 | if (acl_smtp_vrfy != NULL) Ustrcat(buffer, " VRFY"); | |
925ac8e4 | 5431 | smtp_printf("214%s\r\n", FALSE, buffer); |
059ec3d9 PH |
5432 | } |
5433 | break; | |
5434 | ||
5435 | ||
5436 | case EOF_CMD: | |
5437 | incomplete_transaction_log(US"connection lost"); | |
8f128379 PH |
5438 | smtp_notquit_exit(US"connection-lost", US"421", |
5439 | US"%s lost input connection", smtp_active_hostname); | |
059ec3d9 PH |
5440 | |
5441 | /* Don't log by default unless in the middle of a message, as some mailers | |
5442 | just drop the call rather than sending QUIT, and it clutters up the logs. | |
5443 | */ | |
5444 | ||
5445 | if (sender_address != NULL || recipients_count > 0) | |
5446 | log_write(L_lost_incoming_connection, | |
5447 | LOG_MAIN, | |
5448 | "unexpected %s while reading SMTP command from %s%s", | |
5449 | sender_host_unknown? "EOF" : "disconnection", | |
5450 | host_and_ident(FALSE), smtp_read_error); | |
5451 | ||
5452 | else log_write(L_smtp_connection, LOG_MAIN, "%s lost%s", | |
5453 | smtp_get_connection_info(), smtp_read_error); | |
5454 | ||
5455 | done = 1; | |
5456 | break; | |
5457 | ||
5458 | ||
5459 | case ETRN_CMD: | |
b4ed4da0 | 5460 | HAD(SCH_ETRN); |
059ec3d9 PH |
5461 | if (sender_address != NULL) |
5462 | { | |
5463 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5464 | US"ETRN is not permitted inside a transaction"); | |
5465 | break; | |
5466 | } | |
5467 | ||
3ee512ff | 5468 | log_write(L_etrn, LOG_MAIN, "ETRN %s received from %s", smtp_cmd_argument, |
059ec3d9 PH |
5469 | host_and_ident(FALSE)); |
5470 | ||
4f6ae5c3 JH |
5471 | if ((rc = acl_check(ACL_WHERE_ETRN, NULL, acl_smtp_etrn, |
5472 | &user_msg, &log_msg)) != OK) | |
059ec3d9 PH |
5473 | { |
5474 | done = smtp_handle_acl_fail(ACL_WHERE_ETRN, rc, user_msg, log_msg); | |
5475 | break; | |
5476 | } | |
5477 | ||
5478 | /* Compute the serialization key for this command. */ | |
5479 | ||
ca86f471 | 5480 | etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_cmd_data); |
059ec3d9 PH |
5481 | |
5482 | /* If a command has been specified for running as a result of ETRN, we | |
5483 | permit any argument to ETRN. If not, only the # standard form is permitted, | |
5484 | since that is strictly the only kind of ETRN that can be implemented | |
5485 | according to the RFC. */ | |
5486 | ||
5487 | if (smtp_etrn_command != NULL) | |
5488 | { | |
5489 | uschar *error; | |
5490 | BOOL rc; | |
5491 | etrn_command = smtp_etrn_command; | |
ca86f471 | 5492 | deliver_domain = smtp_cmd_data; |
059ec3d9 PH |
5493 | rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL, |
5494 | US"ETRN processing", &error); | |
5495 | deliver_domain = NULL; | |
5496 | if (!rc) | |
5497 | { | |
5498 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to set up ETRN command: %s", | |
5499 | error); | |
925ac8e4 | 5500 | smtp_printf("458 Internal failure\r\n", FALSE); |
059ec3d9 PH |
5501 | break; |
5502 | } | |
5503 | } | |
5504 | ||
5505 | /* Else set up to call Exim with the -R option. */ | |
5506 | ||
5507 | else | |
5508 | { | |
ca86f471 | 5509 | if (*smtp_cmd_data++ != '#') |
059ec3d9 PH |
5510 | { |
5511 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5512 | US"argument must begin with #"); | |
5513 | break; | |
5514 | } | |
5515 | etrn_command = US"exim -R"; | |
e37f8a84 JH |
5516 | argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, |
5517 | *queue_name ? 4 : 2, | |
5518 | US"-R", smtp_cmd_data, | |
5519 | US"-MCG", queue_name); | |
059ec3d9 PH |
5520 | } |
5521 | ||
5522 | /* If we are host-testing, don't actually do anything. */ | |
5523 | ||
5524 | if (host_checking) | |
5525 | { | |
5526 | HDEBUG(D_any) | |
5527 | { | |
5528 | debug_printf("ETRN command is: %s\n", etrn_command); | |
5529 | debug_printf("ETRN command execution skipped\n"); | |
5530 | } | |
925ac8e4 | 5531 | if (user_msg == NULL) smtp_printf("250 OK\r\n", FALSE); |
4e88a19f | 5532 | else smtp_user_msg(US"250", user_msg); |
059ec3d9 PH |
5533 | break; |
5534 | } | |
5535 | ||
5536 | ||
5537 | /* If ETRN queue runs are to be serialized, check the database to | |
5538 | ensure one isn't already running. */ | |
5539 | ||
e8ae7214 | 5540 | if (smtp_etrn_serialize && !enq_start(etrn_serialize_key, 1)) |
059ec3d9 | 5541 | { |
925ac8e4 | 5542 | smtp_printf("458 Already processing %s\r\n", FALSE, smtp_cmd_data); |
059ec3d9 PH |
5543 | break; |
5544 | } | |
5545 | ||
5546 | /* Fork a child process and run the command. We don't want to have to | |
5547 | wait for the process at any point, so set SIGCHLD to SIG_IGN before | |
5548 | forking. It should be set that way anyway for external incoming SMTP, | |
5549 | but we save and restore to be tidy. If serialization is required, we | |
5550 | actually run the command in yet another process, so we can wait for it | |
5551 | to complete and then remove the serialization lock. */ | |
5552 | ||
5553 | oldsignal = signal(SIGCHLD, SIG_IGN); | |
5554 | ||
5555 | if ((pid = fork()) == 0) | |
5556 | { | |
f1e894f3 PH |
5557 | smtp_input = FALSE; /* This process is not associated with the */ |
5558 | (void)fclose(smtp_in); /* SMTP call any more. */ | |
5559 | (void)fclose(smtp_out); | |
059ec3d9 PH |
5560 | |
5561 | signal(SIGCHLD, SIG_DFL); /* Want to catch child */ | |
5562 | ||
5563 | /* If not serializing, do the exec right away. Otherwise, fork down | |
5564 | into another process. */ | |
5565 | ||
5566 | if (!smtp_etrn_serialize || (pid = fork()) == 0) | |
5567 | { | |
5568 | DEBUG(D_exec) debug_print_argv(argv); | |
5569 | exim_nullstd(); /* Ensure std{in,out,err} exist */ | |
5570 | execv(CS argv[0], (char *const *)argv); | |
5571 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "exec of \"%s\" (ETRN) failed: %s", | |
5572 | etrn_command, strerror(errno)); | |
5573 | _exit(EXIT_FAILURE); /* paranoia */ | |
5574 | } | |
5575 | ||
5576 | /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That | |
5577 | is, we are in the first subprocess, after forking again. All we can do | |
5578 | for a failing fork is to log it. Otherwise, wait for the 2nd process to | |
5579 | complete, before removing the serialization. */ | |
5580 | ||
5581 | if (pid < 0) | |
5582 | log_write(0, LOG_MAIN|LOG_PANIC, "2nd fork for serialized ETRN " | |
5583 | "failed: %s", strerror(errno)); | |
5584 | else | |
5585 | { | |
5586 | int status; | |
5587 | DEBUG(D_any) debug_printf("waiting for serialized ETRN process %d\n", | |
5588 | (int)pid); | |
5589 | (void)wait(&status); | |
5590 | DEBUG(D_any) debug_printf("serialized ETRN process %d ended\n", | |
5591 | (int)pid); | |
5592 | } | |
5593 | ||
5594 | enq_end(etrn_serialize_key); | |
5595 | _exit(EXIT_SUCCESS); | |
5596 | } | |
5597 | ||
5598 | /* Back in the top level SMTP process. Check that we started a subprocess | |
5599 | and restore the signal state. */ | |
5600 | ||
5601 | if (pid < 0) | |
5602 | { | |
5603 | log_write(0, LOG_MAIN|LOG_PANIC, "fork of process for ETRN failed: %s", | |
5604 | strerror(errno)); | |
925ac8e4 | 5605 | smtp_printf("458 Unable to fork process\r\n", FALSE); |
059ec3d9 PH |
5606 | if (smtp_etrn_serialize) enq_end(etrn_serialize_key); |
5607 | } | |
4e88a19f PH |
5608 | else |
5609 | { | |
925ac8e4 | 5610 | if (user_msg == NULL) smtp_printf("250 OK\r\n", FALSE); |
4e88a19f PH |
5611 | else smtp_user_msg(US"250", user_msg); |
5612 | } | |
059ec3d9 PH |
5613 | |
5614 | signal(SIGCHLD, oldsignal); | |
5615 | break; | |
5616 | ||
5617 | ||
5618 | case BADARG_CMD: | |
5619 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5620 | US"unexpected argument data"); | |
5621 | break; | |
5622 | ||
5623 | ||
5624 | /* This currently happens only for NULLs, but could be extended. */ | |
5625 | ||
5626 | case BADCHAR_CMD: | |
5627 | done = synprot_error(L_smtp_syntax_error, 0, NULL, /* Just logs */ | |
5628 | US"NULL character(s) present (shown as '?')"); | |
925ac8e4 | 5629 | smtp_printf("501 NULL characters are not allowed in SMTP commands\r\n", FALSE); |
059ec3d9 PH |
5630 | break; |
5631 | ||
5632 | ||
5633 | case BADSYN_CMD: | |
a14e5636 | 5634 | SYNC_FAILURE: |
bd8fbe36 JH |
5635 | if (smtp_inend >= smtp_inbuffer + IN_BUFFER_SIZE) |
5636 | smtp_inend = smtp_inbuffer + IN_BUFFER_SIZE - 1; | |
059ec3d9 PH |
5637 | c = smtp_inend - smtp_inptr; |
5638 | if (c > 150) c = 150; | |
5639 | smtp_inptr[c] = 0; | |
5640 | incomplete_transaction_log(US"sync failure"); | |
3af76a81 | 5641 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error " |
059ec3d9 PH |
5642 | "(next input sent too soon: pipelining was%s advertised): " |
5643 | "rejected \"%s\" %s next input=\"%s\"", | |
5644 | pipelining_advertised? "" : " not", | |
3ee512ff | 5645 | smtp_cmd_buffer, host_and_ident(TRUE), |
059ec3d9 | 5646 | string_printing(smtp_inptr)); |
8f128379 PH |
5647 | smtp_notquit_exit(US"synchronization-error", US"554", |
5648 | US"SMTP synchronization error"); | |
059ec3d9 PH |
5649 | done = 1; /* Pretend eof - drops connection */ |
5650 | break; | |
5651 | ||
5652 | ||
5653 | case TOO_MANY_NONMAIL_CMD: | |
ca86f471 PH |
5654 | s = smtp_cmd_buffer; |
5655 | while (*s != 0 && !isspace(*s)) s++; | |
059ec3d9 PH |
5656 | incomplete_transaction_log(US"too many non-mail commands"); |
5657 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5658 | "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE), | |
6d9cfc47 | 5659 | (int)(s - smtp_cmd_buffer), smtp_cmd_buffer); |
8f128379 | 5660 | smtp_notquit_exit(US"bad-commands", US"554", US"Too many nonmail commands"); |
059ec3d9 PH |
5661 | done = 1; /* Pretend eof - drops connection */ |
5662 | break; | |
5663 | ||
cee5f132 | 5664 | #ifdef SUPPORT_PROXY |
a3c86431 | 5665 | case PROXY_FAIL_IGNORE_CMD: |
925ac8e4 | 5666 | smtp_printf("503 Command refused, required Proxy negotiation failed\r\n", FALSE); |
a3c86431 | 5667 | break; |
cee5f132 | 5668 | #endif |
059ec3d9 PH |
5669 | |
5670 | default: | |
5671 | if (unknown_command_count++ >= smtp_max_unknown_commands) | |
5672 | { | |
5673 | log_write(L_smtp_syntax_error, LOG_MAIN, | |
5674 | "SMTP syntax error in \"%s\" %s %s", | |
3ee512ff | 5675 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), |
059ec3d9 PH |
5676 | US"unrecognized command"); |
5677 | incomplete_transaction_log(US"unrecognized command"); | |
8f128379 PH |
5678 | smtp_notquit_exit(US"bad-commands", US"500", |
5679 | US"Too many unrecognized commands"); | |
059ec3d9 PH |
5680 | done = 2; |
5681 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5682 | "unrecognized commands (last was \"%s\")", host_and_ident(FALSE), | |
0ebc4d69 | 5683 | string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
5684 | } |
5685 | else | |
5686 | done = synprot_error(L_smtp_syntax_error, 500, NULL, | |
5687 | US"unrecognized command"); | |
5688 | break; | |
5689 | } | |
5690 | ||
5691 | /* This label is used by goto's inside loops that want to break out to | |
5692 | the end of the command-processing loop. */ | |
5693 | ||
5694 | COMMAND_LOOP: | |
5695 | last_was_rej_mail = was_rej_mail; /* Remember some last commands for */ | |
5696 | last_was_rcpt = was_rcpt; /* protocol error handling */ | |
5697 | continue; | |
5698 | } | |
5699 | ||
5700 | return done - 2; /* Convert yield values */ | |
5701 | } | |
5702 | ||
e45a1c37 JH |
5703 | /* vi: aw ai sw=2 |
5704 | */ | |
059ec3d9 | 5705 | /* End of smtp_in.c */ |