Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
80fea873 | 5 | /* Copyright (c) University of Cambridge 1995 - 2016 */ |
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 | ||
47 | #define smtp_cmd_buffer_size 16384 | |
059ec3d9 PH |
48 | |
49 | /* Size of buffer for reading SMTP incoming packets */ | |
50 | ||
51 | #define in_buffer_size 8192 | |
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 */ |
18481de3 | 76 | BDAT_CMD, /* Implied by RFC3030 "After all MAIL and..." */ |
059ec3d9 PH |
77 | |
78 | /* This is a dummy to identify the non-sync commands when pipelining */ | |
79 | ||
80 | NON_SYNC_CMD_PIPELINING, | |
81 | ||
82 | /* These commands need not be synchronized when pipelining */ | |
83 | ||
84 | MAIL_CMD, RCPT_CMD, RSET_CMD, | |
85 | ||
86 | /* This is a dummy to identify the non-sync commands when not pipelining */ | |
87 | ||
88 | NON_SYNC_CMD_NON_PIPELINING, | |
89 | ||
90 | /* I have been unable to find a statement about the use of pipelining | |
91 | with AUTH, so to be on the safe side it is here, though I kind of feel | |
92 | it should be up there with the synchronized commands. */ | |
93 | ||
94 | AUTH_CMD, | |
95 | ||
96 | /* I'm not sure about these, but I don't think they matter. */ | |
97 | ||
98 | QUIT_CMD, HELP_CMD, | |
99 | ||
cee5f132 | 100 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
101 | PROXY_FAIL_IGNORE_CMD, |
102 | #endif | |
103 | ||
059ec3d9 PH |
104 | /* These are specials that don't correspond to actual commands */ |
105 | ||
106 | EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD, | |
107 | TOO_MANY_NONMAIL_CMD }; | |
108 | ||
109 | ||
b4ed4da0 PH |
110 | /* This is a convenience macro for adding the identity of an SMTP command |
111 | to the circular buffer that holds a list of the last n received. */ | |
112 | ||
113 | #define HAD(n) \ | |
114 | smtp_connection_had[smtp_ch_index++] = n; \ | |
115 | if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0 | |
116 | ||
059ec3d9 PH |
117 | |
118 | /************************************************* | |
119 | * Local static variables * | |
120 | *************************************************/ | |
121 | ||
122 | static auth_instance *authenticated_by; | |
123 | static BOOL auth_advertised; | |
124 | #ifdef SUPPORT_TLS | |
125 | static BOOL tls_advertised; | |
126 | #endif | |
6c1c3d1d | 127 | static BOOL dsn_advertised; |
059ec3d9 PH |
128 | static BOOL esmtp; |
129 | static BOOL helo_required = FALSE; | |
130 | static BOOL helo_verify = FALSE; | |
131 | static BOOL helo_seen; | |
132 | static BOOL helo_accept_junk; | |
133 | static BOOL count_nonmail; | |
134 | static BOOL pipelining_advertised; | |
2679d413 PH |
135 | static BOOL rcpt_smtp_response_same; |
136 | static BOOL rcpt_in_progress; | |
059ec3d9 | 137 | static int nonmail_command_count; |
8f128379 | 138 | static BOOL smtp_exit_function_called = 0; |
8c5d388a | 139 | #ifdef SUPPORT_I18N |
d1a13eea JH |
140 | static BOOL smtputf8_advertised; |
141 | #endif | |
059ec3d9 PH |
142 | static int synprot_error_count; |
143 | static int unknown_command_count; | |
144 | static int sync_cmd_limit; | |
145 | static int smtp_write_error = 0; | |
146 | ||
2679d413 | 147 | static uschar *rcpt_smtp_response; |
ca86f471 PH |
148 | static uschar *smtp_data_buffer; |
149 | static uschar *smtp_cmd_data; | |
150 | ||
059ec3d9 PH |
151 | /* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their |
152 | final fields of all except AUTH are forced TRUE at the start of a new message | |
153 | setup, to allow one of each between messages that is not counted as a nonmail | |
154 | command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to | |
155 | allow a new EHLO after starting up TLS. | |
156 | ||
157 | AUTH is "falsely" labelled as a mail command initially, so that it doesn't get | |
158 | counted. However, the flag is changed when AUTH is received, so that multiple | |
159 | failing AUTHs will eventually hit the limit. After a successful AUTH, another | |
160 | AUTH is already forbidden. After a TLS session is started, AUTH's flag is again | |
161 | forced TRUE, to allow for the re-authentication that can happen at that point. | |
162 | ||
163 | QUIT is also "falsely" labelled as a mail command so that it doesn't up the | |
2f460950 JH |
164 | count of non-mail commands and possibly provoke an error. |
165 | ||
166 | tls_auth is a pseudo-command, never expected in input. It is activated | |
167 | on TLS startup and looks for a tls authenticator. */ | |
059ec3d9 PH |
168 | |
169 | static smtp_cmd_list cmd_list[] = { | |
d1a13eea JH |
170 | /* name len cmd has_arg is_mail_cmd */ |
171 | ||
059ec3d9 PH |
172 | { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */ |
173 | { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE }, | |
174 | { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE }, | |
175 | { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE }, | |
176 | #ifdef SUPPORT_TLS | |
177 | { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE }, | |
b3ef41c9 | 178 | { "tls_auth", 0, TLS_AUTH_CMD, FALSE, TRUE }, |
059ec3d9 PH |
179 | #endif |
180 | ||
181 | /* If you change anything above here, also fix the definitions below. */ | |
182 | ||
183 | { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE }, | |
184 | { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE }, | |
185 | { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE }, | |
18481de3 | 186 | { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE }, |
059ec3d9 PH |
187 | { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE }, |
188 | { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE }, | |
189 | { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE }, | |
190 | { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE }, | |
191 | { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE }, | |
192 | { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE } | |
193 | }; | |
194 | ||
195 | static smtp_cmd_list *cmd_list_end = | |
196 | cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list); | |
197 | ||
198 | #define CMD_LIST_RSET 0 | |
199 | #define CMD_LIST_HELO 1 | |
200 | #define CMD_LIST_EHLO 2 | |
201 | #define CMD_LIST_AUTH 3 | |
202 | #define CMD_LIST_STARTTLS 4 | |
b3ef41c9 | 203 | #define CMD_LIST_TLS_AUTH 5 |
059ec3d9 | 204 | |
b4ed4da0 PH |
205 | /* This list of names is used for performing the smtp_no_mail logging action. |
206 | It must be kept in step with the SCH_xxx enumerations. */ | |
207 | ||
208 | static uschar *smtp_names[] = | |
209 | { | |
18481de3 JH |
210 | US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN", |
211 | US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET", | |
212 | US"STARTTLS", US"VRFY" }; | |
b4ed4da0 | 213 | |
e524074d | 214 | static uschar *protocols_local[] = { |
981756db PH |
215 | US"local-smtp", /* HELO */ |
216 | US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
217 | US"local-esmtp", /* EHLO */ | |
218 | US"local-esmtps", /* EHLO->STARTTLS->EHLO */ | |
219 | US"local-esmtpa", /* EHLO->AUTH */ | |
220 | US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
059ec3d9 | 221 | }; |
e524074d JH |
222 | static uschar *protocols[] = { |
223 | US"smtp", /* HELO */ | |
224 | US"smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
225 | US"esmtp", /* EHLO */ | |
226 | US"esmtps", /* EHLO->STARTTLS->EHLO */ | |
227 | US"esmtpa", /* EHLO->AUTH */ | |
228 | US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
229 | }; | |
059ec3d9 PH |
230 | |
231 | #define pnormal 0 | |
981756db PH |
232 | #define pextend 2 |
233 | #define pcrpted 1 /* added to pextend or pnormal */ | |
234 | #define pauthed 2 /* added to pextend */ | |
059ec3d9 | 235 | |
d27f98fe TL |
236 | /* Sanity check and validate optional args to MAIL FROM: envelope */ |
237 | enum { | |
2ef7ed08 | 238 | ENV_MAIL_OPT_NULL, |
d27f98fe | 239 | ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH, |
8ccd00b1 | 240 | #ifndef DISABLE_PRDR |
fd98a5c6 | 241 | ENV_MAIL_OPT_PRDR, |
6c1c3d1d | 242 | #endif |
6c1c3d1d | 243 | ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID, |
8c5d388a | 244 | #ifdef SUPPORT_I18N |
d1a13eea JH |
245 | ENV_MAIL_OPT_UTF8, |
246 | #endif | |
d27f98fe TL |
247 | }; |
248 | typedef struct { | |
249 | uschar * name; /* option requested during MAIL cmd */ | |
250 | int value; /* enum type */ | |
251 | BOOL need_value; /* TRUE requires value (name=value pair format) | |
252 | FALSE is a singleton */ | |
253 | } env_mail_type_t; | |
254 | static env_mail_type_t env_mail_type_list[] = { | |
255 | { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE }, | |
256 | { US"BODY", ENV_MAIL_OPT_BODY, TRUE }, | |
257 | { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE }, | |
8ccd00b1 | 258 | #ifndef DISABLE_PRDR |
fd98a5c6 | 259 | { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE }, |
6c1c3d1d | 260 | #endif |
6c1c3d1d WB |
261 | { US"RET", ENV_MAIL_OPT_RET, TRUE }, |
262 | { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE }, | |
8c5d388a | 263 | #ifdef SUPPORT_I18N |
d1a13eea JH |
264 | { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */ |
265 | #endif | |
2ef7ed08 HSHR |
266 | /* keep this the last entry */ |
267 | { US"NULL", ENV_MAIL_OPT_NULL, FALSE }, | |
d27f98fe TL |
268 | }; |
269 | ||
059ec3d9 PH |
270 | /* When reading SMTP from a remote host, we have to use our own versions of the |
271 | C input-reading functions, in order to be able to flush the SMTP output only | |
272 | when about to read more data from the socket. This is the only way to get | |
273 | optimal performance when the client is using pipelining. Flushing for every | |
274 | command causes a separate packet and reply packet each time; saving all the | |
275 | responses up (when pipelining) combines them into one packet and one response. | |
276 | ||
277 | For simplicity, these functions are used for *all* SMTP input, not only when | |
278 | receiving over a socket. However, after setting up a secure socket (SSL), input | |
279 | is read via the OpenSSL library, and another set of functions is used instead | |
280 | (see tls.c). | |
281 | ||
282 | These functions are set in the receive_getc etc. variables and called with the | |
283 | same interface as the C functions. However, since there can only ever be | |
284 | one incoming SMTP call, we just use a single buffer and flags. There is no need | |
285 | to implement a complicated private FILE-like structure.*/ | |
286 | ||
287 | static uschar *smtp_inbuffer; | |
288 | static uschar *smtp_inptr; | |
289 | static uschar *smtp_inend; | |
290 | static int smtp_had_eof; | |
291 | static int smtp_had_error; | |
292 | ||
293 | ||
7e3ce68e JH |
294 | /* forward declarations */ |
295 | int bdat_ungetc(int ch); | |
296 | static int smtp_read_command(BOOL check_sync); | |
297 | static int synprot_error(int type, int code, uschar *data, uschar *errmess); | |
298 | static void smtp_quit_handler(uschar **, uschar **); | |
299 | static void smtp_rset_handler(void); | |
300 | ||
059ec3d9 PH |
301 | /************************************************* |
302 | * SMTP version of getc() * | |
303 | *************************************************/ | |
304 | ||
305 | /* This gets the next byte from the SMTP input buffer. If the buffer is empty, | |
306 | it flushes the output, and refills the buffer, with a timeout. The signal | |
307 | handler is set appropriately by the calling function. This function is not used | |
308 | after a connection has negotated itself into an TLS/SSL state. | |
309 | ||
310 | Arguments: none | |
311 | Returns: the next character or EOF | |
312 | */ | |
313 | ||
314 | int | |
315 | smtp_getc(void) | |
316 | { | |
317 | if (smtp_inptr >= smtp_inend) | |
318 | { | |
319 | int rc, save_errno; | |
320 | fflush(smtp_out); | |
321 | if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); | |
322 | rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size); | |
323 | save_errno = errno; | |
324 | alarm(0); | |
325 | if (rc <= 0) | |
326 | { | |
327 | /* Must put the error text in fixed store, because this might be during | |
328 | header reading, where it releases unused store above the header. */ | |
329 | if (rc < 0) | |
330 | { | |
331 | smtp_had_error = save_errno; | |
332 | smtp_read_error = string_copy_malloc( | |
333 | string_sprintf(" (error: %s)", strerror(save_errno))); | |
334 | } | |
335 | else smtp_had_eof = 1; | |
336 | return EOF; | |
337 | } | |
80a47a2c TK |
338 | #ifndef DISABLE_DKIM |
339 | dkim_exim_verify_feed(smtp_inbuffer, rc); | |
340 | #endif | |
059ec3d9 PH |
341 | smtp_inend = smtp_inbuffer + rc; |
342 | smtp_inptr = smtp_inbuffer; | |
343 | } | |
344 | return *smtp_inptr++; | |
345 | } | |
346 | ||
347 | ||
348 | ||
7e3ce68e JH |
349 | /* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the |
350 | previous BDAT chunk and getting new ones when we run out. Uses the | |
351 | underlying smtp_getc or tls_getc both for that and for getting the | |
352 | (buffered) data byte. EOD signals (an expected) no further data. | |
353 | ERR signals a protocol error, and EOF a closed input stream. | |
354 | ||
355 | Called from read_bdat_smtp() in receive.c for the message body, but also | |
356 | by the headers read loop in receive_msg(); manipulates chunking_state | |
357 | to handle the BDAT command/response. | |
358 | Placed here due to the correlation with the above smtp_getc(), which it wraps, | |
359 | and also by the need to do smtp command/response handling. | |
360 | ||
361 | Arguments: none | |
362 | Returns: the next character or ERR, EOD or EOF | |
363 | */ | |
364 | ||
365 | int | |
366 | bdat_getc(void) | |
367 | { | |
368 | uschar * user_msg = NULL; | |
369 | uschar * log_msg; | |
370 | ||
371 | for(;;) | |
372 | { | |
373 | if (chunking_data_left-- > 0) | |
374 | return lwr_receive_getc(); | |
375 | ||
376 | receive_getc = lwr_receive_getc; | |
377 | receive_ungetc = lwr_receive_ungetc; | |
378 | ||
379 | /* If not the last, ack the received chunk. The last response is delayed | |
380 | until after the data ACL decides on it */ | |
381 | /*XXX find that "last response" and append the chunk size */ | |
382 | ||
383 | if (chunking_state == CHUNKING_LAST) | |
384 | return EOD; | |
385 | ||
386 | chunking_state = CHUNKING_OFFERED; | |
387 | smtp_printf("250 %u byte chunk received\r\n", chunking_datasize); | |
388 | ||
389 | /* Expect another BDAT cmd from input. RFC 3030 says nothing about | |
390 | QUIT, RSET or NOOP but handling them seems obvious */ | |
391 | ||
392 | next_cmd: | |
393 | switch(smtp_read_command(TRUE)) | |
394 | { | |
395 | default: | |
396 | (void) synprot_error(L_smtp_protocol_error, 503, NULL, | |
397 | US"only BDAT permissible after non-LAST BDAT"); | |
398 | ||
399 | repeat_until_rset: | |
400 | switch(smtp_read_command(TRUE)) | |
401 | { | |
402 | case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */ | |
403 | case EOF_CMD: return EOF; | |
404 | case RSET_CMD: smtp_rset_handler(); return ERR; | |
405 | default: if (synprot_error(L_smtp_protocol_error, 503, NULL, | |
406 | US"only RSET accepted now") > 0) | |
407 | return EOF; | |
408 | goto repeat_until_rset; | |
409 | } | |
410 | ||
411 | case QUIT_CMD: | |
412 | smtp_quit_handler(&user_msg, &log_msg); | |
413 | /*FALLTHROUGH*/ | |
414 | case EOF_CMD: | |
415 | return EOF; | |
416 | ||
417 | case RSET_CMD: | |
418 | smtp_rset_handler(); | |
419 | return ERR; | |
420 | ||
421 | case NOOP_CMD: | |
422 | HAD(SCH_NOOP); | |
423 | smtp_printf("250 OK\r\n"); | |
424 | goto next_cmd; | |
425 | ||
426 | case BDAT_CMD: | |
427 | { | |
428 | int n; | |
429 | ||
430 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) | |
431 | { | |
432 | (void) synprot_error(L_smtp_protocol_error, 501, NULL, | |
433 | US"missing size for BDAT command"); | |
434 | return ERR; | |
435 | } | |
436 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
437 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
438 | chunking_data_left = chunking_datasize; | |
439 | ||
440 | if (chunking_datasize == 0) | |
441 | if (chunking_state == CHUNKING_LAST) | |
442 | return EOD; | |
443 | else | |
444 | { | |
445 | (void) synprot_error(L_smtp_protocol_error, 504, NULL, | |
446 | US"zero size for BDAT command"); | |
447 | goto repeat_until_rset; | |
448 | } | |
449 | ||
450 | receive_getc = bdat_getc; | |
451 | receive_ungetc = bdat_ungetc; | |
452 | break; /* to top of main loop */ | |
453 | } | |
454 | } | |
455 | } | |
456 | } | |
457 | ||
458 | ||
459 | ||
460 | ||
059ec3d9 PH |
461 | /************************************************* |
462 | * SMTP version of ungetc() * | |
463 | *************************************************/ | |
464 | ||
465 | /* Puts a character back in the input buffer. Only ever | |
466 | called once. | |
467 | ||
468 | Arguments: | |
469 | ch the character | |
470 | ||
471 | Returns: the character | |
472 | */ | |
473 | ||
474 | int | |
475 | smtp_ungetc(int ch) | |
476 | { | |
7e3ce68e | 477 | *--smtp_inptr = ch; |
059ec3d9 PH |
478 | return ch; |
479 | } | |
480 | ||
481 | ||
7e3ce68e JH |
482 | int |
483 | bdat_ungetc(int ch) | |
484 | { | |
485 | chunking_data_left++; | |
486 | return lwr_receive_ungetc(ch); | |
487 | } | |
488 | ||
059ec3d9 PH |
489 | |
490 | ||
491 | /************************************************* | |
492 | * SMTP version of feof() * | |
493 | *************************************************/ | |
494 | ||
495 | /* Tests for a previous EOF | |
496 | ||
497 | Arguments: none | |
498 | Returns: non-zero if the eof flag is set | |
499 | */ | |
500 | ||
501 | int | |
502 | smtp_feof(void) | |
503 | { | |
504 | return smtp_had_eof; | |
505 | } | |
506 | ||
507 | ||
508 | ||
509 | ||
510 | /************************************************* | |
511 | * SMTP version of ferror() * | |
512 | *************************************************/ | |
513 | ||
514 | /* Tests for a previous read error, and returns with errno | |
515 | restored to what it was when the error was detected. | |
516 | ||
517 | Arguments: none | |
518 | Returns: non-zero if the error flag is set | |
519 | */ | |
520 | ||
521 | int | |
522 | smtp_ferror(void) | |
523 | { | |
524 | errno = smtp_had_error; | |
525 | return smtp_had_error; | |
526 | } | |
527 | ||
528 | ||
529 | ||
58eb016e PH |
530 | /************************************************* |
531 | * Test for characters in the SMTP buffer * | |
532 | *************************************************/ | |
533 | ||
534 | /* Used at the end of a message | |
535 | ||
536 | Arguments: none | |
537 | Returns: TRUE/FALSE | |
538 | */ | |
539 | ||
540 | BOOL | |
541 | smtp_buffered(void) | |
542 | { | |
543 | return smtp_inptr < smtp_inend; | |
544 | } | |
545 | ||
546 | ||
059ec3d9 PH |
547 | |
548 | /************************************************* | |
549 | * Write formatted string to SMTP channel * | |
550 | *************************************************/ | |
551 | ||
552 | /* This is a separate function so that we don't have to repeat everything for | |
553 | TLS support or debugging. It is global so that the daemon and the | |
554 | authentication functions can use it. It does not return any error indication, | |
555 | because major problems such as dropped connections won't show up till an output | |
556 | flush for non-TLS connections. The smtp_fflush() function is available for | |
557 | checking that: for convenience, TLS output errors are remembered here so that | |
558 | they are also picked up later by smtp_fflush(). | |
559 | ||
560 | Arguments: | |
561 | format format string | |
562 | ... optional arguments | |
563 | ||
564 | Returns: nothing | |
565 | */ | |
566 | ||
567 | void | |
1ba28e2b | 568 | smtp_printf(const char *format, ...) |
059ec3d9 PH |
569 | { |
570 | va_list ap; | |
571 | ||
ce552449 NM |
572 | va_start(ap, format); |
573 | smtp_vprintf(format, ap); | |
574 | va_end(ap); | |
575 | } | |
576 | ||
577 | /* This is split off so that verify.c:respond_printf() can, in effect, call | |
578 | smtp_printf(), bearing in mind that in C a vararg function can't directly | |
fb08281f | 579 | call another vararg function, only a function which accepts a va_list. */ |
ce552449 NM |
580 | |
581 | void | |
1ba28e2b | 582 | smtp_vprintf(const char *format, va_list ap) |
ce552449 | 583 | { |
fb08281f DW |
584 | BOOL yield; |
585 | ||
586 | yield = string_vformat(big_buffer, big_buffer_size, format, ap); | |
ce552449 | 587 | |
059ec3d9 PH |
588 | DEBUG(D_receive) |
589 | { | |
fb08281f DW |
590 | void *reset_point = store_get(0); |
591 | uschar *msg_copy, *cr, *end; | |
592 | msg_copy = string_copy(big_buffer); | |
593 | end = msg_copy + Ustrlen(msg_copy); | |
594 | while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */ | |
595 | memmove(cr, cr + 1, (end--) - cr); | |
596 | debug_printf("SMTP>> %s", msg_copy); | |
597 | store_reset(reset_point); | |
059ec3d9 PH |
598 | } |
599 | ||
fb08281f | 600 | if (!yield) |
2679d413 PH |
601 | { |
602 | log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()"); | |
603 | smtp_closedown(US"Unexpected error"); | |
604 | exim_exit(EXIT_FAILURE); | |
605 | } | |
2679d413 PH |
606 | |
607 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs | |
608 | have had the same. Note: this code is also present in smtp_respond(). It would | |
609 | be tidier to have it only in one place, but when it was added, it was easier to | |
610 | do it that way, so as not to have to mess with the code for the RCPT command, | |
611 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
612 | ||
613 | if (rcpt_in_progress) | |
614 | { | |
615 | if (rcpt_smtp_response == NULL) | |
616 | rcpt_smtp_response = string_copy(big_buffer); | |
617 | else if (rcpt_smtp_response_same && | |
618 | Ustrcmp(rcpt_smtp_response, big_buffer) != 0) | |
619 | rcpt_smtp_response_same = FALSE; | |
620 | rcpt_in_progress = FALSE; | |
621 | } | |
059ec3d9 | 622 | |
2679d413 | 623 | /* Now write the string */ |
059ec3d9 PH |
624 | |
625 | #ifdef SUPPORT_TLS | |
817d9f57 | 626 | if (tls_in.active >= 0) |
059ec3d9 | 627 | { |
817d9f57 JH |
628 | if (tls_write(TRUE, big_buffer, Ustrlen(big_buffer)) < 0) |
629 | smtp_write_error = -1; | |
059ec3d9 PH |
630 | } |
631 | else | |
632 | #endif | |
633 | ||
2679d413 | 634 | if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1; |
059ec3d9 PH |
635 | } |
636 | ||
637 | ||
638 | ||
639 | /************************************************* | |
640 | * Flush SMTP out and check for error * | |
641 | *************************************************/ | |
642 | ||
643 | /* This function isn't currently used within Exim (it detects errors when it | |
644 | tries to read the next SMTP input), but is available for use in local_scan(). | |
645 | For non-TLS connections, it flushes the output and checks for errors. For | |
646 | TLS-connections, it checks for a previously-detected TLS write error. | |
647 | ||
648 | Arguments: none | |
649 | Returns: 0 for no error; -1 after an error | |
650 | */ | |
651 | ||
652 | int | |
653 | smtp_fflush(void) | |
654 | { | |
817d9f57 | 655 | if (tls_in.active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1; |
059ec3d9 PH |
656 | return smtp_write_error; |
657 | } | |
658 | ||
659 | ||
660 | ||
661 | /************************************************* | |
662 | * SMTP command read timeout * | |
663 | *************************************************/ | |
664 | ||
665 | /* Signal handler for timing out incoming SMTP commands. This attempts to | |
666 | finish off tidily. | |
667 | ||
668 | Argument: signal number (SIGALRM) | |
669 | Returns: nothing | |
670 | */ | |
671 | ||
672 | static void | |
673 | command_timeout_handler(int sig) | |
674 | { | |
675 | sig = sig; /* Keep picky compilers happy */ | |
676 | log_write(L_lost_incoming_connection, | |
677 | LOG_MAIN, "SMTP command timeout on%s connection from %s", | |
817d9f57 | 678 | (tls_in.active >= 0)? " TLS" : "", |
059ec3d9 PH |
679 | host_and_ident(FALSE)); |
680 | if (smtp_batched_input) | |
681 | moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */ | |
8f128379 PH |
682 | smtp_notquit_exit(US"command-timeout", US"421", |
683 | US"%s: SMTP command timeout - closing connection", smtp_active_hostname); | |
059ec3d9 PH |
684 | exim_exit(EXIT_FAILURE); |
685 | } | |
686 | ||
687 | ||
688 | ||
689 | /************************************************* | |
690 | * SIGTERM received * | |
691 | *************************************************/ | |
692 | ||
693 | /* Signal handler for handling SIGTERM. Again, try to finish tidily. | |
694 | ||
695 | Argument: signal number (SIGTERM) | |
696 | Returns: nothing | |
697 | */ | |
698 | ||
699 | static void | |
700 | command_sigterm_handler(int sig) | |
701 | { | |
702 | sig = sig; /* Keep picky compilers happy */ | |
703 | log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info()); | |
704 | if (smtp_batched_input) | |
705 | moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */ | |
8f128379 PH |
706 | smtp_notquit_exit(US"signal-exit", US"421", |
707 | US"%s: Service not available - closing connection", smtp_active_hostname); | |
059ec3d9 PH |
708 | exim_exit(EXIT_FAILURE); |
709 | } | |
710 | ||
711 | ||
712 | ||
a14e5636 | 713 | |
cee5f132 | 714 | #ifdef SUPPORT_PROXY |
a3bddaa8 TL |
715 | /************************************************* |
716 | * Restore socket timeout to previous value * | |
717 | *************************************************/ | |
718 | /* If the previous value was successfully retrieved, restore | |
719 | it before returning control to the non-proxy routines | |
720 | ||
721 | Arguments: fd - File descriptor for input | |
722 | get_ok - Successfully retrieved previous values | |
723 | tvtmp - Time struct with previous values | |
724 | vslen - Length of time struct | |
725 | Returns: none | |
726 | */ | |
727 | static void | |
728 | restore_socket_timeout(int fd, int get_ok, struct timeval tvtmp, socklen_t vslen) | |
729 | { | |
730 | if (get_ok == 0) | |
731 | setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tvtmp, vslen); | |
732 | } | |
733 | ||
a3c86431 TL |
734 | /************************************************* |
735 | * Check if host is required proxy host * | |
736 | *************************************************/ | |
737 | /* The function determines if inbound host will be a regular smtp host | |
738 | or if it is configured that it must use Proxy Protocol. | |
739 | ||
740 | Arguments: none | |
741 | Returns: bool | |
742 | */ | |
743 | ||
744 | static BOOL | |
745 | check_proxy_protocol_host() | |
746 | { | |
747 | int rc; | |
748 | /* Cannot configure local connection as a proxy inbound */ | |
749 | if (sender_host_address == NULL) return proxy_session; | |
750 | ||
7a2fa0bc | 751 | rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL, |
a3c86431 TL |
752 | sender_host_address, NULL); |
753 | if (rc == OK) | |
754 | { | |
755 | DEBUG(D_receive) | |
756 | debug_printf("Detected proxy protocol configured host\n"); | |
757 | proxy_session = TRUE; | |
758 | } | |
759 | return proxy_session; | |
760 | } | |
761 | ||
762 | ||
a3c86431 TL |
763 | /************************************************* |
764 | * Setup host for proxy protocol * | |
765 | *************************************************/ | |
766 | /* The function configures the connection based on a header from the | |
767 | inbound host to use Proxy Protocol. The specification is very exact | |
768 | so exit with an error if do not find the exact required pieces. This | |
769 | includes an incorrect number of spaces separating args. | |
770 | ||
771 | Arguments: none | |
772 | Returns: int | |
773 | */ | |
774 | ||
775 | static BOOL | |
776 | setup_proxy_protocol_host() | |
777 | { | |
778 | union { | |
779 | struct { | |
780 | uschar line[108]; | |
781 | } v1; | |
782 | struct { | |
783 | uschar sig[12]; | |
36719342 TL |
784 | uint8_t ver_cmd; |
785 | uint8_t fam; | |
786 | uint16_t len; | |
a3c86431 TL |
787 | union { |
788 | struct { /* TCP/UDP over IPv4, len = 12 */ | |
789 | uint32_t src_addr; | |
790 | uint32_t dst_addr; | |
791 | uint16_t src_port; | |
792 | uint16_t dst_port; | |
793 | } ip4; | |
794 | struct { /* TCP/UDP over IPv6, len = 36 */ | |
795 | uint8_t src_addr[16]; | |
796 | uint8_t dst_addr[16]; | |
797 | uint16_t src_port; | |
798 | uint16_t dst_port; | |
799 | } ip6; | |
800 | struct { /* AF_UNIX sockets, len = 216 */ | |
801 | uschar src_addr[108]; | |
802 | uschar dst_addr[108]; | |
803 | } unx; | |
804 | } addr; | |
805 | } v2; | |
806 | } hdr; | |
807 | ||
eb57651e TL |
808 | /* Temp variables used in PPv2 address:port parsing */ |
809 | uint16_t tmpport; | |
810 | char tmpip[INET_ADDRSTRLEN]; | |
811 | struct sockaddr_in tmpaddr; | |
812 | char tmpip6[INET6_ADDRSTRLEN]; | |
813 | struct sockaddr_in6 tmpaddr6; | |
814 | ||
815 | int get_ok = 0; | |
a3c86431 | 816 | int size, ret, fd; |
36719342 | 817 | const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A"; |
a3c86431 TL |
818 | uschar *iptype; /* To display debug info */ |
819 | struct timeval tv; | |
a3bddaa8 TL |
820 | socklen_t vslen = 0; |
821 | struct timeval tvtmp; | |
822 | ||
823 | vslen = sizeof(struct timeval); | |
a3c86431 TL |
824 | |
825 | fd = fileno(smtp_in); | |
826 | ||
a3bddaa8 TL |
827 | /* Save current socket timeout values */ |
828 | get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tvtmp, | |
829 | &vslen); | |
830 | ||
a3c86431 TL |
831 | /* Proxy Protocol host must send header within a short time |
832 | (default 3 seconds) or it's considered invalid */ | |
833 | tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC; | |
834 | tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC; | |
835 | setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv, | |
836 | sizeof(struct timeval)); | |
a3bddaa8 | 837 | |
a3c86431 TL |
838 | do |
839 | { | |
eb57651e TL |
840 | /* The inbound host was declared to be a Proxy Protocol host, so |
841 | don't do a PEEK into the data, actually slurp it up. */ | |
842 | ret = recv(fd, &hdr, sizeof(hdr), 0); | |
a3c86431 TL |
843 | } |
844 | while (ret == -1 && errno == EINTR); | |
845 | ||
846 | if (ret == -1) | |
a3bddaa8 TL |
847 | { |
848 | restore_socket_timeout(fd, get_ok, tvtmp, vslen); | |
a3c86431 | 849 | return (errno == EAGAIN) ? 0 : ERRNO_PROXYFAIL; |
a3bddaa8 | 850 | } |
a3c86431 TL |
851 | |
852 | if (ret >= 16 && | |
36719342 | 853 | memcmp(&hdr.v2, v2sig, 12) == 0) |
a3c86431 | 854 | { |
36719342 TL |
855 | uint8_t ver, cmd; |
856 | ||
857 | /* May 2014: haproxy combined the version and command into one byte to | |
858 | allow two full bytes for the length field in order to proxy SSL | |
859 | connections. SSL Proxy is not supported in this version of Exim, but | |
860 | must still seperate values here. */ | |
861 | ver = (hdr.v2.ver_cmd & 0xf0) >> 4; | |
862 | cmd = (hdr.v2.ver_cmd & 0x0f); | |
863 | ||
864 | if (ver != 0x02) | |
865 | { | |
866 | DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver); | |
867 | goto proxyfail; | |
868 | } | |
a3c86431 | 869 | DEBUG(D_receive) debug_printf("Detected PROXYv2 header\n"); |
36719342 | 870 | /* The v2 header will always be 16 bytes per the spec. */ |
a3c86431 TL |
871 | size = 16 + hdr.v2.len; |
872 | if (ret < size) | |
873 | { | |
36719342 TL |
874 | DEBUG(D_receive) debug_printf("Truncated or too large PROXYv2 header (%d/%d)\n", |
875 | ret, size); | |
a3c86431 TL |
876 | goto proxyfail; |
877 | } | |
36719342 | 878 | switch (cmd) |
a3c86431 TL |
879 | { |
880 | case 0x01: /* PROXY command */ | |
881 | switch (hdr.v2.fam) | |
882 | { | |
eb57651e TL |
883 | case 0x11: /* TCPv4 address type */ |
884 | iptype = US"IPv4"; | |
885 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr; | |
886 | inet_ntop(AF_INET, &(tmpaddr.sin_addr), (char *)&tmpip, sizeof(tmpip)); | |
887 | if (!string_is_ip_address(US tmpip,NULL)) | |
888 | { | |
889 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
a3c86431 | 890 | return ERRNO_PROXYFAIL; |
eb57651e | 891 | } |
e6d2a989 | 892 | proxy_local_address = sender_host_address; |
eb57651e TL |
893 | sender_host_address = string_copy(US tmpip); |
894 | tmpport = ntohs(hdr.v2.addr.ip4.src_port); | |
e6d2a989 | 895 | proxy_local_port = sender_host_port; |
eb57651e TL |
896 | sender_host_port = tmpport; |
897 | /* Save dest ip/port */ | |
898 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr; | |
899 | inet_ntop(AF_INET, &(tmpaddr.sin_addr), (char *)&tmpip, sizeof(tmpip)); | |
900 | if (!string_is_ip_address(US tmpip,NULL)) | |
901 | { | |
902 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
903 | return ERRNO_PROXYFAIL; | |
904 | } | |
7a2fa0bc | 905 | proxy_external_address = string_copy(US tmpip); |
eb57651e | 906 | tmpport = ntohs(hdr.v2.addr.ip4.dst_port); |
7a2fa0bc | 907 | proxy_external_port = tmpport; |
a3c86431 | 908 | goto done; |
eb57651e TL |
909 | case 0x21: /* TCPv6 address type */ |
910 | iptype = US"IPv6"; | |
911 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16); | |
912 | inet_ntop(AF_INET6, &(tmpaddr6.sin6_addr), (char *)&tmpip6, sizeof(tmpip6)); | |
913 | if (!string_is_ip_address(US tmpip6,NULL)) | |
914 | { | |
915 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
916 | return ERRNO_PROXYFAIL; | |
917 | } | |
e6d2a989 | 918 | proxy_local_address = sender_host_address; |
eb57651e TL |
919 | sender_host_address = string_copy(US tmpip6); |
920 | tmpport = ntohs(hdr.v2.addr.ip6.src_port); | |
e6d2a989 | 921 | proxy_local_port = sender_host_port; |
eb57651e TL |
922 | sender_host_port = tmpport; |
923 | /* Save dest ip/port */ | |
924 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16); | |
925 | inet_ntop(AF_INET6, &(tmpaddr6.sin6_addr), (char *)&tmpip6, sizeof(tmpip6)); | |
926 | if (!string_is_ip_address(US tmpip6,NULL)) | |
927 | { | |
928 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
a3c86431 | 929 | return ERRNO_PROXYFAIL; |
eb57651e | 930 | } |
7a2fa0bc | 931 | proxy_external_address = string_copy(US tmpip6); |
eb57651e | 932 | tmpport = ntohs(hdr.v2.addr.ip6.dst_port); |
7a2fa0bc | 933 | proxy_external_port = tmpport; |
a3c86431 | 934 | goto done; |
eb57651e TL |
935 | default: |
936 | DEBUG(D_receive) | |
937 | debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n", | |
938 | hdr.v2.fam); | |
939 | goto proxyfail; | |
a3c86431 TL |
940 | } |
941 | /* Unsupported protocol, keep local connection address */ | |
942 | break; | |
943 | case 0x00: /* LOCAL command */ | |
944 | /* Keep local connection address for LOCAL */ | |
945 | break; | |
946 | default: | |
eb57651e | 947 | DEBUG(D_receive) |
36719342 | 948 | debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd); |
a3c86431 TL |
949 | goto proxyfail; |
950 | } | |
951 | } | |
952 | else if (ret >= 8 && | |
953 | memcmp(hdr.v1.line, "PROXY", 5) == 0) | |
954 | { | |
955 | uschar *p = string_copy(hdr.v1.line); | |
956 | uschar *end = memchr(p, '\r', ret - 1); | |
957 | uschar *sp; /* Utility variables follow */ | |
958 | int tmp_port; | |
959 | char *endc; | |
960 | ||
961 | if (!end || end[1] != '\n') | |
962 | { | |
963 | DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n"); | |
964 | goto proxyfail; | |
965 | } | |
966 | *end = '\0'; /* Terminate the string */ | |
967 | size = end + 2 - hdr.v1.line; /* Skip header + CRLF */ | |
968 | DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n"); | |
969 | /* Step through the string looking for the required fields. Ensure | |
970 | strict adherance to required formatting, exit for any error. */ | |
971 | p += 5; | |
972 | if (!isspace(*(p++))) | |
973 | { | |
974 | DEBUG(D_receive) debug_printf("Missing space after PROXY command\n"); | |
975 | goto proxyfail; | |
976 | } | |
977 | if (!Ustrncmp(p, CCS"TCP4", 4)) | |
978 | iptype = US"IPv4"; | |
979 | else if (!Ustrncmp(p,CCS"TCP6", 4)) | |
980 | iptype = US"IPv6"; | |
981 | else if (!Ustrncmp(p,CCS"UNKNOWN", 7)) | |
982 | { | |
983 | iptype = US"Unknown"; | |
984 | goto done; | |
985 | } | |
986 | else | |
987 | { | |
988 | DEBUG(D_receive) debug_printf("Invalid TCP type\n"); | |
989 | goto proxyfail; | |
990 | } | |
991 | ||
992 | p += Ustrlen(iptype); | |
993 | if (!isspace(*(p++))) | |
994 | { | |
995 | DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n"); | |
996 | goto proxyfail; | |
997 | } | |
998 | /* Find the end of the arg */ | |
999 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1000 | { | |
1001 | DEBUG(D_receive) | |
1002 | debug_printf("Did not find proxied src %s\n", iptype); | |
1003 | goto proxyfail; | |
1004 | } | |
1005 | *sp = '\0'; | |
1006 | if(!string_is_ip_address(p,NULL)) | |
1007 | { | |
1008 | DEBUG(D_receive) | |
1009 | debug_printf("Proxied src arg is not an %s address\n", iptype); | |
1010 | goto proxyfail; | |
1011 | } | |
e6d2a989 | 1012 | proxy_local_address = sender_host_address; |
a3c86431 TL |
1013 | sender_host_address = p; |
1014 | p = sp + 1; | |
1015 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1016 | { | |
1017 | DEBUG(D_receive) | |
1018 | debug_printf("Did not find proxy dest %s\n", iptype); | |
1019 | goto proxyfail; | |
1020 | } | |
1021 | *sp = '\0'; | |
1022 | if(!string_is_ip_address(p,NULL)) | |
1023 | { | |
1024 | DEBUG(D_receive) | |
1025 | debug_printf("Proxy dest arg is not an %s address\n", iptype); | |
1026 | goto proxyfail; | |
1027 | } | |
7a2fa0bc | 1028 | proxy_external_address = p; |
a3c86431 TL |
1029 | p = sp + 1; |
1030 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1031 | { | |
1032 | DEBUG(D_receive) debug_printf("Did not find proxied src port\n"); | |
1033 | goto proxyfail; | |
1034 | } | |
1035 | *sp = '\0'; | |
1036 | tmp_port = strtol(CCS p,&endc,10); | |
1037 | if (*endc || tmp_port == 0) | |
1038 | { | |
1039 | DEBUG(D_receive) | |
1040 | debug_printf("Proxied src port '%s' not an integer\n", p); | |
1041 | goto proxyfail; | |
1042 | } | |
e6d2a989 | 1043 | proxy_local_port = sender_host_port; |
a3c86431 TL |
1044 | sender_host_port = tmp_port; |
1045 | p = sp + 1; | |
1046 | if ((sp = Ustrchr(p, '\0')) == NULL) | |
1047 | { | |
1048 | DEBUG(D_receive) debug_printf("Did not find proxy dest port\n"); | |
1049 | goto proxyfail; | |
1050 | } | |
1051 | tmp_port = strtol(CCS p,&endc,10); | |
1052 | if (*endc || tmp_port == 0) | |
1053 | { | |
1054 | DEBUG(D_receive) | |
1055 | debug_printf("Proxy dest port '%s' not an integer\n", p); | |
1056 | goto proxyfail; | |
1057 | } | |
7a2fa0bc | 1058 | proxy_external_port = tmp_port; |
a3c86431 TL |
1059 | /* Already checked for /r /n above. Good V1 header received. */ |
1060 | goto done; | |
1061 | } | |
1062 | else | |
1063 | { | |
1064 | /* Wrong protocol */ | |
eb57651e | 1065 | DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n"); |
a3c86431 TL |
1066 | goto proxyfail; |
1067 | } | |
1068 | ||
1069 | proxyfail: | |
a3bddaa8 | 1070 | restore_socket_timeout(fd, get_ok, tvtmp, vslen); |
a3c86431 | 1071 | /* Don't flush any potential buffer contents. Any input should cause a |
eb57651e | 1072 | synchronization failure */ |
a3c86431 TL |
1073 | return FALSE; |
1074 | ||
1075 | done: | |
a3bddaa8 | 1076 | restore_socket_timeout(fd, get_ok, tvtmp, vslen); |
a3c86431 | 1077 | DEBUG(D_receive) |
eb57651e | 1078 | debug_printf("Valid %s sender from Proxy Protocol header\n", iptype); |
a3c86431 TL |
1079 | return proxy_session; |
1080 | } | |
1081 | #endif | |
1082 | ||
059ec3d9 PH |
1083 | /************************************************* |
1084 | * Read one command line * | |
1085 | *************************************************/ | |
1086 | ||
1087 | /* Strictly, SMTP commands coming over the net are supposed to end with CRLF. | |
1088 | There are sites that don't do this, and in any case internal SMTP probably | |
1089 | should check only for LF. Consequently, we check here for LF only. The line | |
1090 | ends up with [CR]LF removed from its end. If we get an overlong line, treat as | |
3ee512ff PH |
1091 | an unknown command. The command is read into the global smtp_cmd_buffer so that |
1092 | it is available via $smtp_command. | |
059ec3d9 PH |
1093 | |
1094 | The character reading routine sets up a timeout for each block actually read | |
1095 | from the input (which may contain more than one command). We set up a special | |
1096 | signal handler that closes down the session on a timeout. Control does not | |
1097 | return when it runs. | |
1098 | ||
1099 | Arguments: | |
1100 | check_sync if TRUE, check synchronization rules if global option is TRUE | |
1101 | ||
1102 | Returns: a code identifying the command (enumerated above) | |
1103 | */ | |
1104 | ||
1105 | static int | |
1106 | smtp_read_command(BOOL check_sync) | |
1107 | { | |
1108 | int c; | |
1109 | int ptr = 0; | |
1110 | smtp_cmd_list *p; | |
1111 | BOOL hadnull = FALSE; | |
1112 | ||
1113 | os_non_restarting_signal(SIGALRM, command_timeout_handler); | |
1114 | ||
1115 | while ((c = (receive_getc)()) != '\n' && c != EOF) | |
1116 | { | |
3ee512ff | 1117 | if (ptr >= smtp_cmd_buffer_size) |
059ec3d9 PH |
1118 | { |
1119 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1120 | return OTHER_CMD; | |
1121 | } | |
1122 | if (c == 0) | |
1123 | { | |
1124 | hadnull = TRUE; | |
1125 | c = '?'; | |
1126 | } | |
3ee512ff | 1127 | smtp_cmd_buffer[ptr++] = c; |
059ec3d9 PH |
1128 | } |
1129 | ||
1130 | receive_linecount++; /* For BSMTP errors */ | |
1131 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1132 | ||
1133 | /* If hit end of file, return pseudo EOF command. Whether we have a | |
1134 | part-line already read doesn't matter, since this is an error state. */ | |
1135 | ||
1136 | if (c == EOF) return EOF_CMD; | |
1137 | ||
1138 | /* Remove any CR and white space at the end of the line, and terminate the | |
1139 | string. */ | |
1140 | ||
3ee512ff PH |
1141 | while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--; |
1142 | smtp_cmd_buffer[ptr] = 0; | |
059ec3d9 | 1143 | |
3ee512ff | 1144 | DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer); |
059ec3d9 PH |
1145 | |
1146 | /* NULLs are not allowed in SMTP commands */ | |
1147 | ||
1148 | if (hadnull) return BADCHAR_CMD; | |
1149 | ||
1150 | /* Scan command list and return identity, having set the data pointer | |
1151 | to the start of the actual data characters. Check for SMTP synchronization | |
1152 | if required. */ | |
1153 | ||
1154 | for (p = cmd_list; p < cmd_list_end; p++) | |
1155 | { | |
cee5f132 | 1156 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
1157 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
1158 | if (proxy_session && proxy_session_failed) | |
1159 | { | |
1160 | if (p->cmd != QUIT_CMD) | |
1161 | continue; | |
1162 | } | |
1163 | #endif | |
2f460950 JH |
1164 | if ( p->len |
1165 | && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0 | |
1166 | && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */ | |
1167 | || smtp_cmd_buffer[p->len] == 0 | |
1168 | || smtp_cmd_buffer[p->len] == ' ' | |
1169 | ) ) | |
059ec3d9 PH |
1170 | { |
1171 | if (smtp_inptr < smtp_inend && /* Outstanding input */ | |
1172 | p->cmd < sync_cmd_limit && /* Command should sync */ | |
1173 | check_sync && /* Local flag set */ | |
1174 | smtp_enforce_sync && /* Global flag set */ | |
1175 | sender_host_address != NULL && /* Not local input */ | |
1176 | !sender_host_notsocket) /* Really is a socket */ | |
1177 | return BADSYN_CMD; | |
1178 | ||
ca86f471 PH |
1179 | /* The variables $smtp_command and $smtp_command_argument point into the |
1180 | unmodified input buffer. A copy of the latter is taken for actual | |
1181 | processing, so that it can be chopped up into separate parts if necessary, | |
1182 | for example, when processing a MAIL command options such as SIZE that can | |
1183 | follow the sender address. */ | |
059ec3d9 | 1184 | |
3ee512ff | 1185 | smtp_cmd_argument = smtp_cmd_buffer + p->len; |
ca86f471 PH |
1186 | while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++; |
1187 | Ustrcpy(smtp_data_buffer, smtp_cmd_argument); | |
1188 | smtp_cmd_data = smtp_data_buffer; | |
059ec3d9 PH |
1189 | |
1190 | /* Count non-mail commands from those hosts that are controlled in this | |
1191 | way. The default is all hosts. We don't waste effort checking the list | |
1192 | until we get a non-mail command, but then cache the result to save checking | |
1193 | again. If there's a DEFER while checking the host, assume it's in the list. | |
1194 | ||
1195 | Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the | |
1196 | start of each incoming message by fiddling with the value in the table. */ | |
1197 | ||
1198 | if (!p->is_mail_cmd) | |
1199 | { | |
1200 | if (count_nonmail == TRUE_UNSET) count_nonmail = | |
1201 | verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL; | |
1202 | if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail) | |
1203 | return TOO_MANY_NONMAIL_CMD; | |
1204 | } | |
1205 | ||
ca86f471 PH |
1206 | /* If there is data for a command that does not expect it, generate the |
1207 | error here. */ | |
059ec3d9 | 1208 | |
ca86f471 | 1209 | return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD; |
059ec3d9 PH |
1210 | } |
1211 | } | |
1212 | ||
cee5f132 | 1213 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
1214 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
1215 | if (proxy_session && proxy_session_failed) | |
1216 | return PROXY_FAIL_IGNORE_CMD; | |
1217 | #endif | |
1218 | ||
059ec3d9 PH |
1219 | /* Enforce synchronization for unknown commands */ |
1220 | ||
1221 | if (smtp_inptr < smtp_inend && /* Outstanding input */ | |
1222 | check_sync && /* Local flag set */ | |
1223 | smtp_enforce_sync && /* Global flag set */ | |
1224 | sender_host_address != NULL && /* Not local input */ | |
1225 | !sender_host_notsocket) /* Really is a socket */ | |
1226 | return BADSYN_CMD; | |
1227 | ||
1228 | return OTHER_CMD; | |
1229 | } | |
1230 | ||
1231 | ||
1232 | ||
a14e5636 PH |
1233 | /************************************************* |
1234 | * Recheck synchronization * | |
1235 | *************************************************/ | |
1236 | ||
1237 | /* Synchronization checks can never be perfect because a packet may be on its | |
1238 | way but not arrived when the check is done. Such checks can in any case only be | |
1239 | done when TLS is not in use. Normally, the checks happen when commands are | |
1240 | read: Exim ensures that there is no more input in the input buffer. In normal | |
1241 | cases, the response to the command will be fast, and there is no further check. | |
1242 | ||
1243 | However, for some commands an ACL is run, and that can include delays. In those | |
1244 | cases, it is useful to do another check on the input just before sending the | |
1245 | response. This also applies at the start of a connection. This function does | |
1246 | that check by means of the select() function, as long as the facility is not | |
1247 | disabled or inappropriate. A failure of select() is ignored. | |
1248 | ||
1249 | When there is unwanted input, we read it so that it appears in the log of the | |
1250 | error. | |
1251 | ||
1252 | Arguments: none | |
1253 | Returns: TRUE if all is well; FALSE if there is input pending | |
1254 | */ | |
1255 | ||
1256 | static BOOL | |
1257 | check_sync(void) | |
1258 | { | |
1259 | int fd, rc; | |
1260 | fd_set fds; | |
1261 | struct timeval tzero; | |
1262 | ||
1263 | if (!smtp_enforce_sync || sender_host_address == NULL || | |
817d9f57 | 1264 | sender_host_notsocket || tls_in.active >= 0) |
a14e5636 PH |
1265 | return TRUE; |
1266 | ||
1267 | fd = fileno(smtp_in); | |
1268 | FD_ZERO(&fds); | |
1269 | FD_SET(fd, &fds); | |
1270 | tzero.tv_sec = 0; | |
1271 | tzero.tv_usec = 0; | |
1272 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero); | |
1273 | ||
1274 | if (rc <= 0) return TRUE; /* Not ready to read */ | |
1275 | rc = smtp_getc(); | |
1276 | if (rc < 0) return TRUE; /* End of file or error */ | |
1277 | ||
1278 | smtp_ungetc(rc); | |
1279 | rc = smtp_inend - smtp_inptr; | |
1280 | if (rc > 150) rc = 150; | |
1281 | smtp_inptr[rc] = 0; | |
1282 | return FALSE; | |
1283 | } | |
1284 | ||
1285 | ||
1286 | ||
059ec3d9 PH |
1287 | /************************************************* |
1288 | * Forced closedown of call * | |
1289 | *************************************************/ | |
1290 | ||
1291 | /* This function is called from log.c when Exim is dying because of a serious | |
1292 | disaster, and also from some other places. If an incoming non-batched SMTP | |
1293 | channel is open, it swallows the rest of the incoming message if in the DATA | |
1294 | phase, sends the reply string, and gives an error to all subsequent commands | |
1295 | except QUIT. The existence of an SMTP call is detected by the non-NULLness of | |
1296 | smtp_in. | |
1297 | ||
8f128379 PH |
1298 | Arguments: |
1299 | message SMTP reply string to send, excluding the code | |
1300 | ||
059ec3d9 PH |
1301 | Returns: nothing |
1302 | */ | |
1303 | ||
1304 | void | |
1305 | smtp_closedown(uschar *message) | |
1306 | { | |
1307 | if (smtp_in == NULL || smtp_batched_input) return; | |
1308 | receive_swallow_smtp(); | |
1309 | smtp_printf("421 %s\r\n", message); | |
1310 | ||
1311 | for (;;) | |
1312 | { | |
1313 | switch(smtp_read_command(FALSE)) | |
1314 | { | |
1315 | case EOF_CMD: | |
1316 | return; | |
1317 | ||
1318 | case QUIT_CMD: | |
1319 | smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); | |
1320 | mac_smtp_fflush(); | |
1321 | return; | |
1322 | ||
1323 | case RSET_CMD: | |
1324 | smtp_printf("250 Reset OK\r\n"); | |
1325 | break; | |
1326 | ||
1327 | default: | |
1328 | smtp_printf("421 %s\r\n", message); | |
1329 | break; | |
1330 | } | |
1331 | } | |
1332 | } | |
1333 | ||
1334 | ||
1335 | ||
1336 | ||
1337 | /************************************************* | |
1338 | * Set up connection info for logging * | |
1339 | *************************************************/ | |
1340 | ||
1341 | /* This function is called when logging information about an SMTP connection. | |
1342 | It sets up appropriate source information, depending on the type of connection. | |
dac79d3e PH |
1343 | If sender_fullhost is NULL, we are at a very early stage of the connection; |
1344 | just use the IP address. | |
059ec3d9 PH |
1345 | |
1346 | Argument: none | |
1347 | Returns: a string describing the connection | |
1348 | */ | |
1349 | ||
1350 | uschar * | |
1351 | smtp_get_connection_info(void) | |
1352 | { | |
dac79d3e PH |
1353 | uschar *hostname = (sender_fullhost == NULL)? |
1354 | sender_host_address : sender_fullhost; | |
1355 | ||
059ec3d9 | 1356 | if (host_checking) |
dac79d3e | 1357 | return string_sprintf("SMTP connection from %s", hostname); |
059ec3d9 PH |
1358 | |
1359 | if (sender_host_unknown || sender_host_notsocket) | |
1360 | return string_sprintf("SMTP connection from %s", sender_ident); | |
1361 | ||
1362 | if (is_inetd) | |
dac79d3e | 1363 | return string_sprintf("SMTP connection from %s (via inetd)", hostname); |
059ec3d9 | 1364 | |
6c6d6e48 | 1365 | if (LOGGING(incoming_interface) && interface_address != NULL) |
dac79d3e | 1366 | return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname, |
059ec3d9 PH |
1367 | interface_address, interface_port); |
1368 | ||
dac79d3e | 1369 | return string_sprintf("SMTP connection from %s", hostname); |
059ec3d9 PH |
1370 | } |
1371 | ||
1372 | ||
1373 | ||
e45a1c37 | 1374 | #ifdef SUPPORT_TLS |
887291d2 JH |
1375 | /* Append TLS-related information to a log line |
1376 | ||
1377 | Arguments: | |
1378 | s String under construction: allocated string to extend, or NULL | |
1379 | sizep Pointer to current allocation size (update on return), or NULL | |
1380 | ptrp Pointer to index for new entries in string (update on return), or NULL | |
1381 | ||
1382 | Returns: Allocated string or NULL | |
1383 | */ | |
e45a1c37 JH |
1384 | static uschar * |
1385 | s_tlslog(uschar * s, int * sizep, int * ptrp) | |
1386 | { | |
1387 | int size = sizep ? *sizep : 0; | |
1388 | int ptr = ptrp ? *ptrp : 0; | |
1389 | ||
6c6d6e48 | 1390 | if (LOGGING(tls_cipher) && tls_in.cipher != NULL) |
e45a1c37 | 1391 | s = string_append(s, &size, &ptr, 2, US" X=", tls_in.cipher); |
6c6d6e48 | 1392 | if (LOGGING(tls_certificate_verified) && tls_in.cipher != NULL) |
e45a1c37 JH |
1393 | s = string_append(s, &size, &ptr, 2, US" CV=", |
1394 | tls_in.certificate_verified? "yes":"no"); | |
6c6d6e48 | 1395 | if (LOGGING(tls_peerdn) && tls_in.peerdn != NULL) |
e45a1c37 JH |
1396 | s = string_append(s, &size, &ptr, 3, US" DN=\"", |
1397 | string_printing(tls_in.peerdn), US"\""); | |
6c6d6e48 | 1398 | if (LOGGING(tls_sni) && tls_in.sni != NULL) |
e45a1c37 JH |
1399 | s = string_append(s, &size, &ptr, 3, US" SNI=\"", |
1400 | string_printing(tls_in.sni), US"\""); | |
1401 | ||
67d81c10 JH |
1402 | if (s) |
1403 | { | |
1404 | s[ptr] = '\0'; | |
1405 | if (sizep) *sizep = size; | |
1406 | if (ptrp) *ptrp = ptr; | |
1407 | } | |
e45a1c37 JH |
1408 | return s; |
1409 | } | |
1410 | #endif | |
1411 | ||
b4ed4da0 PH |
1412 | /************************************************* |
1413 | * Log lack of MAIL if so configured * | |
1414 | *************************************************/ | |
1415 | ||
1416 | /* This function is called when an SMTP session ends. If the log selector | |
1417 | smtp_no_mail is set, write a log line giving some details of what has happened | |
1418 | in the SMTP session. | |
1419 | ||
1420 | Arguments: none | |
1421 | Returns: nothing | |
1422 | */ | |
1423 | ||
1424 | void | |
1425 | smtp_log_no_mail(void) | |
1426 | { | |
1427 | int size, ptr, i; | |
1428 | uschar *s, *sep; | |
1429 | ||
6c6d6e48 | 1430 | if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail)) |
b4ed4da0 PH |
1431 | return; |
1432 | ||
1433 | s = NULL; | |
1434 | size = ptr = 0; | |
1435 | ||
1436 | if (sender_host_authenticated != NULL) | |
1437 | { | |
1438 | s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated); | |
1439 | if (authenticated_id != NULL) | |
1440 | s = string_append(s, &size, &ptr, 2, US":", authenticated_id); | |
1441 | } | |
1442 | ||
1443 | #ifdef SUPPORT_TLS | |
e45a1c37 | 1444 | s = s_tlslog(s, &size, &ptr); |
3f0945ff | 1445 | #endif |
b4ed4da0 PH |
1446 | |
1447 | sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)? | |
1448 | US" C=..." : US" C="; | |
1449 | for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++) | |
1450 | { | |
1451 | if (smtp_connection_had[i] != SCH_NONE) | |
1452 | { | |
1453 | s = string_append(s, &size, &ptr, 2, sep, | |
1454 | smtp_names[smtp_connection_had[i]]); | |
1455 | sep = US","; | |
1456 | } | |
1457 | } | |
1458 | ||
1459 | for (i = 0; i < smtp_ch_index; i++) | |
1460 | { | |
1461 | s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]); | |
1462 | sep = US","; | |
1463 | } | |
1464 | ||
1465 | if (s != NULL) s[ptr] = 0; else s = US""; | |
1466 | log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s", | |
1467 | host_and_ident(FALSE), | |
19050083 JH |
1468 | readconf_printtime( (int) ((long)time(NULL) - (long)smtp_connection_start)), |
1469 | s); | |
b4ed4da0 PH |
1470 | } |
1471 | ||
1472 | ||
1473 | ||
059ec3d9 PH |
1474 | /************************************************* |
1475 | * Check HELO line and set sender_helo_name * | |
1476 | *************************************************/ | |
1477 | ||
1478 | /* Check the format of a HELO line. The data for HELO/EHLO is supposed to be | |
1479 | the domain name of the sending host, or an ip literal in square brackets. The | |
1480 | arrgument is placed in sender_helo_name, which is in malloc store, because it | |
1481 | must persist over multiple incoming messages. If helo_accept_junk is set, this | |
1482 | host is permitted to send any old junk (needed for some broken hosts). | |
1483 | Otherwise, helo_allow_chars can be used for rogue characters in general | |
1484 | (typically people want to let in underscores). | |
1485 | ||
1486 | Argument: | |
1487 | s the data portion of the line (already past any white space) | |
1488 | ||
1489 | Returns: TRUE or FALSE | |
1490 | */ | |
1491 | ||
1492 | static BOOL | |
1493 | check_helo(uschar *s) | |
1494 | { | |
1495 | uschar *start = s; | |
1496 | uschar *end = s + Ustrlen(s); | |
1497 | BOOL yield = helo_accept_junk; | |
1498 | ||
1499 | /* Discard any previous helo name */ | |
1500 | ||
1501 | if (sender_helo_name != NULL) | |
1502 | { | |
1503 | store_free(sender_helo_name); | |
1504 | sender_helo_name = NULL; | |
1505 | } | |
1506 | ||
1507 | /* Skip tests if junk is permitted. */ | |
1508 | ||
1509 | if (!yield) | |
1510 | { | |
1511 | /* Allow the new standard form for IPv6 address literals, namely, | |
1512 | [IPv6:....], and because someone is bound to use it, allow an equivalent | |
1513 | IPv4 form. Allow plain addresses as well. */ | |
1514 | ||
1515 | if (*s == '[') | |
1516 | { | |
1517 | if (end[-1] == ']') | |
1518 | { | |
1519 | end[-1] = 0; | |
1520 | if (strncmpic(s, US"[IPv6:", 6) == 0) | |
1521 | yield = (string_is_ip_address(s+6, NULL) == 6); | |
1522 | else if (strncmpic(s, US"[IPv4:", 6) == 0) | |
1523 | yield = (string_is_ip_address(s+6, NULL) == 4); | |
1524 | else | |
1525 | yield = (string_is_ip_address(s+1, NULL) != 0); | |
1526 | end[-1] = ']'; | |
1527 | } | |
1528 | } | |
1529 | ||
1530 | /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars | |
1531 | that have been configured (usually underscore - sigh). */ | |
1532 | ||
1533 | else if (*s != 0) | |
1534 | { | |
1535 | yield = TRUE; | |
1536 | while (*s != 0) | |
1537 | { | |
1538 | if (!isalnum(*s) && *s != '.' && *s != '-' && | |
1539 | Ustrchr(helo_allow_chars, *s) == NULL) | |
1540 | { | |
1541 | yield = FALSE; | |
1542 | break; | |
1543 | } | |
1544 | s++; | |
1545 | } | |
1546 | } | |
1547 | } | |
1548 | ||
1549 | /* Save argument if OK */ | |
1550 | ||
1551 | if (yield) sender_helo_name = string_copy_malloc(start); | |
1552 | return yield; | |
1553 | } | |
1554 | ||
1555 | ||
1556 | ||
1557 | ||
1558 | ||
1559 | /************************************************* | |
1560 | * Extract SMTP command option * | |
1561 | *************************************************/ | |
1562 | ||
ca86f471 | 1563 | /* This function picks the next option setting off the end of smtp_cmd_data. It |
059ec3d9 PH |
1564 | is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP |
1565 | things that can appear there. | |
1566 | ||
1567 | Arguments: | |
1568 | name point this at the name | |
1569 | value point this at the data string | |
1570 | ||
1571 | Returns: TRUE if found an option | |
1572 | */ | |
1573 | ||
1574 | static BOOL | |
1575 | extract_option(uschar **name, uschar **value) | |
1576 | { | |
1577 | uschar *n; | |
ca86f471 | 1578 | uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1; |
059ec3d9 PH |
1579 | while (isspace(*v)) v--; |
1580 | v[1] = 0; | |
ca86f471 | 1581 | while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) v--; |
059ec3d9 PH |
1582 | |
1583 | n = v; | |
fd98a5c6 JH |
1584 | if (*v == '=') |
1585 | { | |
1586 | while(isalpha(n[-1])) n--; | |
1587 | /* RFC says SP, but TAB seen in wild and other major MTAs accept it */ | |
1588 | if (!isspace(n[-1])) return FALSE; | |
1589 | n[-1] = 0; | |
1590 | } | |
1591 | else | |
1592 | { | |
1593 | n++; | |
1594 | if (v == smtp_cmd_data) return FALSE; | |
1595 | } | |
059ec3d9 | 1596 | *v++ = 0; |
fd98a5c6 | 1597 | *name = n; |
059ec3d9 PH |
1598 | *value = v; |
1599 | return TRUE; | |
1600 | } | |
1601 | ||
1602 | ||
1603 | ||
1604 | ||
1605 | ||
059ec3d9 PH |
1606 | /************************************************* |
1607 | * Reset for new message * | |
1608 | *************************************************/ | |
1609 | ||
1610 | /* This function is called whenever the SMTP session is reset from | |
1611 | within either of the setup functions. | |
1612 | ||
1613 | Argument: the stacking pool storage reset point | |
1614 | Returns: nothing | |
1615 | */ | |
1616 | ||
1617 | static void | |
1618 | smtp_reset(void *reset_point) | |
1619 | { | |
059ec3d9 PH |
1620 | store_reset(reset_point); |
1621 | recipients_list = NULL; | |
1622 | rcpt_count = rcpt_defer_count = rcpt_fail_count = | |
1623 | raw_recipients_count = recipients_count = recipients_list_max = 0; | |
2e5b33cd | 1624 | cancel_cutthrough_connection("smtp reset"); |
2e0c1448 | 1625 | message_linecount = 0; |
059ec3d9 | 1626 | message_size = -1; |
71fafd95 | 1627 | acl_added_headers = NULL; |
e7568d51 | 1628 | acl_removed_headers = NULL; |
059ec3d9 | 1629 | queue_only_policy = FALSE; |
2679d413 PH |
1630 | rcpt_smtp_response = NULL; |
1631 | rcpt_smtp_response_same = TRUE; | |
1632 | rcpt_in_progress = FALSE; | |
69358f02 | 1633 | deliver_freeze = FALSE; /* Can be set by ACL */ |
6a3f1455 | 1634 | freeze_tell = freeze_tell_config; /* Can be set by ACL */ |
29aba418 | 1635 | fake_response = OK; /* Can be set by ACL */ |
6951ac6c | 1636 | #ifdef WITH_CONTENT_SCAN |
8523533c TK |
1637 | no_mbox_unspool = FALSE; /* Can be set by ACL */ |
1638 | #endif | |
69358f02 | 1639 | submission_mode = FALSE; /* Can be set by ACL */ |
f4ee74ac | 1640 | suppress_local_fixups = suppress_local_fixups_default; /* Can be set by ACL */ |
69358f02 PH |
1641 | active_local_from_check = local_from_check; /* Can be set by ACL */ |
1642 | active_local_sender_retain = local_sender_retain; /* Can be set by ACL */ | |
059ec3d9 | 1643 | sender_address = NULL; |
2fe1a124 | 1644 | submission_name = NULL; /* Can be set by ACL */ |
059ec3d9 PH |
1645 | raw_sender = NULL; /* After SMTP rewrite, before qualifying */ |
1646 | sender_address_unrewritten = NULL; /* Set only after verify rewrite */ | |
1647 | sender_verified_list = NULL; /* No senders verified */ | |
1648 | memset(sender_address_cache, 0, sizeof(sender_address_cache)); | |
1649 | memset(sender_domain_cache, 0, sizeof(sender_domain_cache)); | |
6c1c3d1d | 1650 | |
059ec3d9 | 1651 | authenticated_sender = NULL; |
8523533c TK |
1652 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
1653 | bmi_run = 0; | |
1654 | bmi_verdicts = NULL; | |
1655 | #endif | |
80a47a2c | 1656 | #ifndef DISABLE_DKIM |
9e5d6b55 | 1657 | dkim_signers = NULL; |
80a47a2c TK |
1658 | dkim_disable_verify = FALSE; |
1659 | dkim_collect_input = FALSE; | |
f7572e5a | 1660 | #endif |
aa368db3 JH |
1661 | dsn_ret = 0; |
1662 | dsn_envid = NULL; | |
1663 | #ifndef DISABLE_PRDR | |
1664 | prdr_requested = FALSE; | |
1665 | #endif | |
8523533c TK |
1666 | #ifdef EXPERIMENTAL_SPF |
1667 | spf_header_comment = NULL; | |
1668 | spf_received = NULL; | |
8e669ac1 | 1669 | spf_result = NULL; |
8523533c TK |
1670 | spf_smtp_comment = NULL; |
1671 | #endif | |
8c5d388a | 1672 | #ifdef SUPPORT_I18N |
d1a13eea JH |
1673 | message_smtputf8 = FALSE; |
1674 | #endif | |
059ec3d9 PH |
1675 | body_linecount = body_zerocount = 0; |
1676 | ||
870f6ba8 TF |
1677 | sender_rate = sender_rate_limit = sender_rate_period = NULL; |
1678 | ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */ | |
1679 | /* Note that ratelimiters_conn persists across resets. */ | |
1680 | ||
38a0a95f | 1681 | /* Reset message ACL variables */ |
47ca6d6c | 1682 | |
38a0a95f | 1683 | acl_var_m = NULL; |
059ec3d9 PH |
1684 | |
1685 | /* The message body variables use malloc store. They may be set if this is | |
1686 | not the first message in an SMTP session and the previous message caused them | |
1687 | to be referenced in an ACL. */ | |
1688 | ||
1689 | if (message_body != NULL) | |
1690 | { | |
1691 | store_free(message_body); | |
1692 | message_body = NULL; | |
1693 | } | |
1694 | ||
1695 | if (message_body_end != NULL) | |
1696 | { | |
1697 | store_free(message_body_end); | |
1698 | message_body_end = NULL; | |
1699 | } | |
1700 | ||
1701 | /* Warning log messages are also saved in malloc store. They are saved to avoid | |
1702 | repetition in the same message, but it seems right to repeat them for different | |
4e88a19f | 1703 | messages. */ |
059ec3d9 PH |
1704 | |
1705 | while (acl_warn_logged != NULL) | |
1706 | { | |
1707 | string_item *this = acl_warn_logged; | |
1708 | acl_warn_logged = acl_warn_logged->next; | |
1709 | store_free(this); | |
1710 | } | |
1711 | } | |
1712 | ||
1713 | ||
1714 | ||
1715 | ||
1716 | ||
1717 | /************************************************* | |
1718 | * Initialize for incoming batched SMTP message * | |
1719 | *************************************************/ | |
1720 | ||
1721 | /* This function is called from smtp_setup_msg() in the case when | |
1722 | smtp_batched_input is true. This happens when -bS is used to pass a whole batch | |
1723 | of messages in one file with SMTP commands between them. All errors must be | |
1724 | reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are | |
1725 | relevant. After an error on a sender, or an invalid recipient, the remainder | |
1726 | of the message is skipped. The value of received_protocol is already set. | |
1727 | ||
1728 | Argument: none | |
1729 | Returns: > 0 message successfully started (reached DATA) | |
1730 | = 0 QUIT read or end of file reached | |
1731 | < 0 should not occur | |
1732 | */ | |
1733 | ||
1734 | static int | |
1735 | smtp_setup_batch_msg(void) | |
1736 | { | |
1737 | int done = 0; | |
1738 | void *reset_point = store_get(0); | |
1739 | ||
1740 | /* Save the line count at the start of each transaction - single commands | |
1741 | like HELO and RSET count as whole transactions. */ | |
1742 | ||
1743 | bsmtp_transaction_linecount = receive_linecount; | |
1744 | ||
1745 | if ((receive_feof)()) return 0; /* Treat EOF as QUIT */ | |
1746 | ||
1747 | smtp_reset(reset_point); /* Reset for start of message */ | |
1748 | ||
1749 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
1750 | value. The values are 2 larger than the required yield of the function. */ | |
1751 | ||
1752 | while (done <= 0) | |
1753 | { | |
1754 | uschar *errmess; | |
1755 | uschar *recipient = NULL; | |
1756 | int start, end, sender_domain, recipient_domain; | |
1757 | ||
1758 | switch(smtp_read_command(FALSE)) | |
1759 | { | |
1760 | /* The HELO/EHLO commands set sender_address_helo if they have | |
1761 | valid data; otherwise they are ignored, except that they do | |
1762 | a reset of the state. */ | |
1763 | ||
1764 | case HELO_CMD: | |
1765 | case EHLO_CMD: | |
1766 | ||
ca86f471 | 1767 | check_helo(smtp_cmd_data); |
059ec3d9 PH |
1768 | /* Fall through */ |
1769 | ||
1770 | case RSET_CMD: | |
1771 | smtp_reset(reset_point); | |
1772 | bsmtp_transaction_linecount = receive_linecount; | |
1773 | break; | |
1774 | ||
1775 | ||
1776 | /* The MAIL FROM command requires an address as an operand. All we | |
1777 | do here is to parse it for syntactic correctness. The form "<>" is | |
1778 | a special case which converts into an empty string. The start/end | |
1779 | pointers in the original are not used further for this address, as | |
1780 | it is the canonical extracted address which is all that is kept. */ | |
1781 | ||
1782 | case MAIL_CMD: | |
474f71bf | 1783 | smtp_mailcmd_count++; /* Count for no-mail log */ |
059ec3d9 PH |
1784 | if (sender_address != NULL) |
1785 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1786 | moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given"); |
059ec3d9 | 1787 | |
ca86f471 | 1788 | if (smtp_cmd_data[0] == 0) |
059ec3d9 | 1789 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 1790 | moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand"); |
059ec3d9 PH |
1791 | |
1792 | /* Reset to start of message */ | |
1793 | ||
1794 | smtp_reset(reset_point); | |
1795 | ||
1796 | /* Apply SMTP rewrite */ | |
1797 | ||
1798 | raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)? | |
ca86f471 PH |
1799 | rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE, |
1800 | US"", global_rewrite_rules) : smtp_cmd_data; | |
059ec3d9 PH |
1801 | |
1802 | /* Extract the address; the TRUE flag allows <> as valid */ | |
1803 | ||
1804 | raw_sender = | |
1805 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
1806 | TRUE); | |
1807 | ||
1808 | if (raw_sender == NULL) | |
1809 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1810 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); |
059ec3d9 PH |
1811 | |
1812 | sender_address = string_copy(raw_sender); | |
1813 | ||
1814 | /* Qualify unqualified sender addresses if permitted to do so. */ | |
1815 | ||
1816 | if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@') | |
1817 | { | |
1818 | if (allow_unqualified_sender) | |
1819 | { | |
1820 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
1821 | DEBUG(D_receive) debug_printf("unqualified address %s accepted " | |
1822 | "and rewritten\n", raw_sender); | |
1823 | } | |
1824 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1825 | else moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain " |
059ec3d9 PH |
1826 | "a domain"); |
1827 | } | |
1828 | break; | |
1829 | ||
1830 | ||
1831 | /* The RCPT TO command requires an address as an operand. All we do | |
1832 | here is to parse it for syntactic correctness. There may be any number | |
1833 | of RCPT TO commands, specifying multiple senders. We build them all into | |
1834 | a data structure that is in argc/argv format. The start/end values | |
1835 | given by parse_extract_address are not used, as we keep only the | |
1836 | extracted address. */ | |
1837 | ||
1838 | case RCPT_CMD: | |
1839 | if (sender_address == NULL) | |
1840 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1841 | moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given"); |
059ec3d9 | 1842 | |
ca86f471 | 1843 | if (smtp_cmd_data[0] == 0) |
059ec3d9 | 1844 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 1845 | moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand"); |
059ec3d9 PH |
1846 | |
1847 | /* Check maximum number allowed */ | |
1848 | ||
1849 | if (recipients_max > 0 && recipients_count + 1 > recipients_max) | |
1850 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1851 | moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients", |
059ec3d9 PH |
1852 | recipients_max_reject? "552": "452"); |
1853 | ||
1854 | /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a | |
1855 | recipient address */ | |
1856 | ||
2685d6e0 JH |
1857 | recipient = rewrite_existflags & rewrite_smtp |
1858 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
1859 | global_rewrite_rules) | |
1860 | : smtp_cmd_data; | |
059ec3d9 | 1861 | |
059ec3d9 PH |
1862 | recipient = parse_extract_address(recipient, &errmess, &start, &end, |
1863 | &recipient_domain, FALSE); | |
059ec3d9 | 1864 | |
2685d6e0 | 1865 | if (!recipient) |
059ec3d9 | 1866 | /* The function moan_smtp_batch() does not return. */ |
3ee512ff | 1867 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); |
059ec3d9 PH |
1868 | |
1869 | /* If the recipient address is unqualified, qualify it if permitted. Then | |
1870 | add it to the list of recipients. */ | |
1871 | ||
1872 | if (recipient_domain == 0) | |
1873 | { | |
1874 | if (allow_unqualified_recipient) | |
1875 | { | |
1876 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
1877 | recipient); | |
1878 | recipient = rewrite_address_qualify(recipient, TRUE); | |
1879 | } | |
1880 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1881 | else moan_smtp_batch(smtp_cmd_buffer, "501 recipient address must contain " |
059ec3d9 PH |
1882 | "a domain"); |
1883 | } | |
1884 | receive_add_recipient(recipient, -1); | |
1885 | break; | |
1886 | ||
1887 | ||
1888 | /* The DATA command is legal only if it follows successful MAIL FROM | |
1889 | and RCPT TO commands. This function is complete when a valid DATA | |
1890 | command is encountered. */ | |
1891 | ||
1892 | case DATA_CMD: | |
1893 | if (sender_address == NULL || recipients_count <= 0) | |
1894 | { | |
1895 | /* The function moan_smtp_batch() does not return. */ | |
1896 | if (sender_address == NULL) | |
3ee512ff | 1897 | moan_smtp_batch(smtp_cmd_buffer, |
059ec3d9 PH |
1898 | "503 MAIL FROM:<sender> command must precede DATA"); |
1899 | else | |
3ee512ff | 1900 | moan_smtp_batch(smtp_cmd_buffer, |
059ec3d9 PH |
1901 | "503 RCPT TO:<recipient> must precede DATA"); |
1902 | } | |
1903 | else | |
1904 | { | |
1905 | done = 3; /* DATA successfully achieved */ | |
1906 | message_ended = END_NOTENDED; /* Indicate in middle of message */ | |
1907 | } | |
1908 | break; | |
1909 | ||
1910 | ||
1911 | /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */ | |
1912 | ||
1913 | case VRFY_CMD: | |
1914 | case EXPN_CMD: | |
1915 | case HELP_CMD: | |
1916 | case NOOP_CMD: | |
1917 | case ETRN_CMD: | |
1918 | bsmtp_transaction_linecount = receive_linecount; | |
1919 | break; | |
1920 | ||
1921 | ||
1922 | case EOF_CMD: | |
1923 | case QUIT_CMD: | |
1924 | done = 2; | |
1925 | break; | |
1926 | ||
1927 | ||
1928 | case BADARG_CMD: | |
1929 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1930 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data"); |
059ec3d9 PH |
1931 | break; |
1932 | ||
1933 | ||
1934 | case BADCHAR_CMD: | |
1935 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1936 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command"); |
059ec3d9 PH |
1937 | break; |
1938 | ||
1939 | ||
1940 | default: | |
1941 | /* The function moan_smtp_batch() does not return. */ | |
3ee512ff | 1942 | moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized"); |
059ec3d9 PH |
1943 | break; |
1944 | } | |
1945 | } | |
1946 | ||
1947 | return done - 2; /* Convert yield values */ | |
1948 | } | |
1949 | ||
1950 | ||
1951 | ||
1952 | ||
1953 | /************************************************* | |
1954 | * Start an SMTP session * | |
1955 | *************************************************/ | |
1956 | ||
1957 | /* This function is called at the start of an SMTP session. Thereafter, | |
1958 | smtp_setup_msg() is called to initiate each separate message. This | |
1959 | function does host-specific testing, and outputs the banner line. | |
1960 | ||
1961 | Arguments: none | |
1962 | Returns: FALSE if the session can not continue; something has | |
1963 | gone wrong, or the connection to the host is blocked | |
1964 | */ | |
1965 | ||
1966 | BOOL | |
1967 | smtp_start_session(void) | |
1968 | { | |
1969 | int size = 256; | |
4e88a19f PH |
1970 | int ptr, esclen; |
1971 | uschar *user_msg, *log_msg; | |
1972 | uschar *code, *esc; | |
059ec3d9 PH |
1973 | uschar *p, *s, *ss; |
1974 | ||
b4ed4da0 PH |
1975 | smtp_connection_start = time(NULL); |
1976 | for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++) | |
1977 | smtp_connection_had[smtp_ch_index] = SCH_NONE; | |
1978 | smtp_ch_index = 0; | |
1979 | ||
00f00ca5 PH |
1980 | /* Default values for certain variables */ |
1981 | ||
059ec3d9 | 1982 | helo_seen = esmtp = helo_accept_junk = FALSE; |
b4ed4da0 | 1983 | smtp_mailcmd_count = 0; |
059ec3d9 PH |
1984 | count_nonmail = TRUE_UNSET; |
1985 | synprot_error_count = unknown_command_count = nonmail_command_count = 0; | |
1986 | smtp_delay_mail = smtp_rlm_base; | |
1987 | auth_advertised = FALSE; | |
1988 | pipelining_advertised = FALSE; | |
cf8b11a5 | 1989 | pipelining_enable = TRUE; |
059ec3d9 | 1990 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; |
8f128379 | 1991 | smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */ |
059ec3d9 | 1992 | |
33d73e3b PH |
1993 | /* If receiving by -bs from a trusted user, or testing with -bh, we allow |
1994 | authentication settings from -oMaa to remain in force. */ | |
1995 | ||
1996 | if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL; | |
059ec3d9 PH |
1997 | authenticated_by = NULL; |
1998 | ||
1999 | #ifdef SUPPORT_TLS | |
817d9f57 | 2000 | tls_in.cipher = tls_in.peerdn = NULL; |
9d1c15ef JH |
2001 | tls_in.ourcert = tls_in.peercert = NULL; |
2002 | tls_in.sni = NULL; | |
44662487 | 2003 | tls_in.ocsp = OCSP_NOT_REQ; |
059ec3d9 PH |
2004 | tls_advertised = FALSE; |
2005 | #endif | |
6c1c3d1d | 2006 | dsn_advertised = FALSE; |
8c5d388a | 2007 | #ifdef SUPPORT_I18N |
d1a13eea JH |
2008 | smtputf8_advertised = FALSE; |
2009 | #endif | |
059ec3d9 PH |
2010 | |
2011 | /* Reset ACL connection variables */ | |
2012 | ||
38a0a95f | 2013 | acl_var_c = NULL; |
059ec3d9 | 2014 | |
ca86f471 | 2015 | /* Allow for trailing 0 in the command and data buffers. */ |
3ee512ff | 2016 | |
ca86f471 | 2017 | smtp_cmd_buffer = (uschar *)malloc(2*smtp_cmd_buffer_size + 2); |
3ee512ff | 2018 | if (smtp_cmd_buffer == NULL) |
059ec3d9 PH |
2019 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
2020 | "malloc() failed for SMTP command buffer"); | |
2416c261 | 2021 | smtp_cmd_buffer[0] = 0; |
ca86f471 | 2022 | smtp_data_buffer = smtp_cmd_buffer + smtp_cmd_buffer_size + 1; |
059ec3d9 PH |
2023 | |
2024 | /* For batched input, the protocol setting can be overridden from the | |
2025 | command line by a trusted caller. */ | |
2026 | ||
2027 | if (smtp_batched_input) | |
2028 | { | |
2029 | if (received_protocol == NULL) received_protocol = US"local-bsmtp"; | |
2030 | } | |
2031 | ||
2032 | /* For non-batched SMTP input, the protocol setting is forced here. It will be | |
2033 | reset later if any of EHLO/AUTH/STARTTLS are received. */ | |
2034 | ||
2035 | else | |
2036 | received_protocol = | |
e524074d | 2037 | (sender_host_address ? protocols : protocols_local) [pnormal]; |
059ec3d9 PH |
2038 | |
2039 | /* Set up the buffer for inputting using direct read() calls, and arrange to | |
2040 | call the local functions instead of the standard C ones. */ | |
2041 | ||
2042 | smtp_inbuffer = (uschar *)malloc(in_buffer_size); | |
2043 | if (smtp_inbuffer == NULL) | |
2044 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer"); | |
2045 | receive_getc = smtp_getc; | |
2046 | receive_ungetc = smtp_ungetc; | |
2047 | receive_feof = smtp_feof; | |
2048 | receive_ferror = smtp_ferror; | |
58eb016e | 2049 | receive_smtp_buffered = smtp_buffered; |
059ec3d9 PH |
2050 | smtp_inptr = smtp_inend = smtp_inbuffer; |
2051 | smtp_had_eof = smtp_had_error = 0; | |
2052 | ||
2053 | /* Set up the message size limit; this may be host-specific */ | |
2054 | ||
d45b1de8 PH |
2055 | thismessage_size_limit = expand_string_integer(message_size_limit, TRUE); |
2056 | if (expand_string_message != NULL) | |
059ec3d9 PH |
2057 | { |
2058 | if (thismessage_size_limit == -1) | |
2059 | log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: " | |
2060 | "%s", expand_string_message); | |
2061 | else | |
2062 | log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: " | |
2063 | "%s", expand_string_message); | |
2064 | smtp_closedown(US"Temporary local problem - please try later"); | |
2065 | return FALSE; | |
2066 | } | |
2067 | ||
2068 | /* When a message is input locally via the -bs or -bS options, sender_host_ | |
2069 | unknown is set unless -oMa was used to force an IP address, in which case it | |
2070 | is checked like a real remote connection. When -bs is used from inetd, this | |
2071 | flag is not set, causing the sending host to be checked. The code that deals | |
2072 | with IP source routing (if configured) is never required for -bs or -bS and | |
2073 | the flag sender_host_notsocket is used to suppress it. | |
2074 | ||
2075 | If smtp_accept_max and smtp_accept_reserve are set, keep some connections in | |
2076 | reserve for certain hosts and/or networks. */ | |
2077 | ||
2078 | if (!sender_host_unknown) | |
2079 | { | |
2080 | int rc; | |
2081 | BOOL reserved_host = FALSE; | |
2082 | ||
2083 | /* Look up IP options (source routing info) on the socket if this is not an | |
2084 | -oMa "host", and if any are found, log them and drop the connection. | |
2085 | ||
2086 | Linux (and others now, see below) is different to everyone else, so there | |
2087 | has to be some conditional compilation here. Versions of Linux before 2.1.15 | |
2088 | used a structure whose name was "options". Somebody finally realized that | |
2089 | this name was silly, and it got changed to "ip_options". I use the | |
2090 | newer name here, but there is a fudge in the script that sets up os.h | |
2091 | to define a macro in older Linux systems. | |
2092 | ||
2093 | Sigh. Linux is a fast-moving target. Another generation of Linux uses | |
2094 | glibc 2, which has chosen ip_opts for the structure name. This is now | |
2095 | really a glibc thing rather than a Linux thing, so the condition name | |
2096 | has been changed to reflect this. It is relevant also to GNU/Hurd. | |
2097 | ||
2098 | Mac OS 10.x (Darwin) is like the later glibc versions, but without the | |
2099 | setting of the __GLIBC__ macro, so we can't detect it automatically. There's | |
2100 | a special macro defined in the os.h file. | |
2101 | ||
2102 | Some DGUX versions on older hardware appear not to support IP options at | |
2103 | all, so there is now a general macro which can be set to cut out this | |
2104 | support altogether. | |
2105 | ||
2106 | How to do this properly in IPv6 is not yet known. */ | |
2107 | ||
2108 | #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS) | |
2109 | ||
2110 | #ifdef GLIBC_IP_OPTIONS | |
2111 | #if (!defined __GLIBC__) || (__GLIBC__ < 2) | |
2112 | #define OPTSTYLE 1 | |
2113 | #else | |
2114 | #define OPTSTYLE 2 | |
2115 | #endif | |
2116 | #elif defined DARWIN_IP_OPTIONS | |
2117 | #define OPTSTYLE 2 | |
2118 | #else | |
2119 | #define OPTSTYLE 3 | |
2120 | #endif | |
2121 | ||
2122 | if (!host_checking && !sender_host_notsocket) | |
2123 | { | |
2124 | #if OPTSTYLE == 1 | |
36a3b041 | 2125 | EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN; |
059ec3d9 PH |
2126 | struct ip_options *ipopt = store_get(optlen); |
2127 | #elif OPTSTYLE == 2 | |
2128 | struct ip_opts ipoptblock; | |
2129 | struct ip_opts *ipopt = &ipoptblock; | |
36a3b041 | 2130 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); |
059ec3d9 PH |
2131 | #else |
2132 | struct ipoption ipoptblock; | |
2133 | struct ipoption *ipopt = &ipoptblock; | |
36a3b041 | 2134 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); |
059ec3d9 PH |
2135 | #endif |
2136 | ||
2137 | /* Occasional genuine failures of getsockopt() have been seen - for | |
2138 | example, "reset by peer". Therefore, just log and give up on this | |
2139 | call, unless the error is ENOPROTOOPT. This error is given by systems | |
2140 | that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time | |
2141 | of writing. So for that error, carry on - we just can't do an IP options | |
2142 | check. */ | |
2143 | ||
2144 | DEBUG(D_receive) debug_printf("checking for IP options\n"); | |
2145 | ||
2146 | if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt), | |
2147 | &optlen) < 0) | |
2148 | { | |
2149 | if (errno != ENOPROTOOPT) | |
2150 | { | |
2151 | log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s", | |
2152 | host_and_ident(FALSE), strerror(errno)); | |
2153 | smtp_printf("451 SMTP service not available\r\n"); | |
2154 | return FALSE; | |
2155 | } | |
2156 | } | |
2157 | ||
2158 | /* Deal with any IP options that are set. On the systems I have looked at, | |
2159 | the value of MAX_IPOPTLEN has been 40, meaning that there should never be | |
2160 | more logging data than will fit in big_buffer. Nevertheless, after somebody | |
2161 | questioned this code, I've added in some paranoid checking. */ | |
2162 | ||
2163 | else if (optlen > 0) | |
2164 | { | |
2165 | uschar *p = big_buffer; | |
2166 | uschar *pend = big_buffer + big_buffer_size; | |
2167 | uschar *opt, *adptr; | |
2168 | int optcount; | |
2169 | struct in_addr addr; | |
2170 | ||
2171 | #if OPTSTYLE == 1 | |
2172 | uschar *optstart = (uschar *)(ipopt->__data); | |
2173 | #elif OPTSTYLE == 2 | |
2174 | uschar *optstart = (uschar *)(ipopt->ip_opts); | |
2175 | #else | |
2176 | uschar *optstart = (uschar *)(ipopt->ipopt_list); | |
2177 | #endif | |
2178 | ||
2179 | DEBUG(D_receive) debug_printf("IP options exist\n"); | |
2180 | ||
2181 | Ustrcpy(p, "IP options on incoming call:"); | |
2182 | p += Ustrlen(p); | |
2183 | ||
2184 | for (opt = optstart; opt != NULL && | |
2185 | opt < (uschar *)(ipopt) + optlen;) | |
2186 | { | |
2187 | switch (*opt) | |
2188 | { | |
2189 | case IPOPT_EOL: | |
2190 | opt = NULL; | |
2191 | break; | |
2192 | ||
2193 | case IPOPT_NOP: | |
2194 | opt++; | |
2195 | break; | |
2196 | ||
2197 | case IPOPT_SSRR: | |
2198 | case IPOPT_LSRR: | |
2199 | if (!string_format(p, pend-p, " %s [@%s", | |
2200 | (*opt == IPOPT_SSRR)? "SSRR" : "LSRR", | |
2201 | #if OPTSTYLE == 1 | |
2202 | inet_ntoa(*((struct in_addr *)(&(ipopt->faddr)))))) | |
2203 | #elif OPTSTYLE == 2 | |
2204 | inet_ntoa(ipopt->ip_dst))) | |
2205 | #else | |
2206 | inet_ntoa(ipopt->ipopt_dst))) | |
2207 | #endif | |
2208 | { | |
2209 | opt = NULL; | |
2210 | break; | |
2211 | } | |
2212 | ||
2213 | p += Ustrlen(p); | |
2214 | optcount = (opt[1] - 3) / sizeof(struct in_addr); | |
2215 | adptr = opt + 3; | |
2216 | while (optcount-- > 0) | |
2217 | { | |
2218 | memcpy(&addr, adptr, sizeof(addr)); | |
2219 | if (!string_format(p, pend - p - 1, "%s%s", | |
2220 | (optcount == 0)? ":" : "@", inet_ntoa(addr))) | |
2221 | { | |
2222 | opt = NULL; | |
2223 | break; | |
2224 | } | |
2225 | p += Ustrlen(p); | |
2226 | adptr += sizeof(struct in_addr); | |
2227 | } | |
2228 | *p++ = ']'; | |
2229 | opt += opt[1]; | |
2230 | break; | |
2231 | ||
2232 | default: | |
2233 | { | |
2234 | int i; | |
2235 | if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; } | |
2236 | Ustrcat(p, "[ "); | |
2237 | p += 2; | |
2238 | for (i = 0; i < opt[1]; i++) | |
2239 | { | |
2240 | sprintf(CS p, "%2.2x ", opt[i]); | |
2241 | p += 3; | |
2242 | } | |
2243 | *p++ = ']'; | |
2244 | } | |
2245 | opt += opt[1]; | |
2246 | break; | |
2247 | } | |
2248 | } | |
2249 | ||
2250 | *p = 0; | |
2251 | log_write(0, LOG_MAIN, "%s", big_buffer); | |
2252 | ||
2253 | /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */ | |
2254 | ||
2255 | log_write(0, LOG_MAIN|LOG_REJECT, | |
2256 | "connection from %s refused (IP options)", host_and_ident(FALSE)); | |
2257 | ||
2258 | smtp_printf("554 SMTP service not available\r\n"); | |
2259 | return FALSE; | |
2260 | } | |
2261 | ||
2262 | /* Length of options = 0 => there are no options */ | |
2263 | ||
2264 | else DEBUG(D_receive) debug_printf("no IP options found\n"); | |
2265 | } | |
2266 | #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */ | |
2267 | ||
2268 | /* Set keep-alive in socket options. The option is on by default. This | |
2269 | setting is an attempt to get rid of some hanging connections that stick in | |
2270 | read() when the remote end (usually a dialup) goes away. */ | |
2271 | ||
2272 | if (smtp_accept_keepalive && !sender_host_notsocket) | |
2273 | ip_keepalive(fileno(smtp_out), sender_host_address, FALSE); | |
2274 | ||
2275 | /* If the current host matches host_lookup, set the name by doing a | |
2276 | reverse lookup. On failure, sender_host_name will be NULL and | |
2277 | host_lookup_failed will be TRUE. This may or may not be serious - optional | |
2278 | checks later. */ | |
2279 | ||
2280 | if (verify_check_host(&host_lookup) == OK) | |
2281 | { | |
2282 | (void)host_name_lookup(); | |
2283 | host_build_sender_fullhost(); | |
2284 | } | |
2285 | ||
2286 | /* Delay this until we have the full name, if it is looked up. */ | |
2287 | ||
2288 | set_process_info("handling incoming connection from %s", | |
2289 | host_and_ident(FALSE)); | |
2290 | ||
1ad6489e JH |
2291 | /* Expand smtp_receive_timeout, if needed */ |
2292 | ||
2293 | if (smtp_receive_timeout_s) | |
2294 | { | |
2295 | uschar * exp; | |
2296 | if ( !(exp = expand_string(smtp_receive_timeout_s)) | |
2297 | || !(*exp) | |
2298 | || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0 | |
2299 | ) | |
2300 | log_write(0, LOG_MAIN|LOG_PANIC, | |
2301 | "bad value for smtp_receive_timeout: '%s'", exp ? exp : US""); | |
2302 | } | |
2303 | ||
059ec3d9 PH |
2304 | /* Start up TLS if tls_on_connect is set. This is for supporting the legacy |
2305 | smtps port for use with older style SSL MTAs. */ | |
2306 | ||
2307 | #ifdef SUPPORT_TLS | |
817d9f57 | 2308 | if (tls_in.on_connect && tls_server_start(tls_require_ciphers) != OK) |
059ec3d9 PH |
2309 | return FALSE; |
2310 | #endif | |
2311 | ||
2312 | /* Test for explicit connection rejection */ | |
2313 | ||
2314 | if (verify_check_host(&host_reject_connection) == OK) | |
2315 | { | |
2316 | log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection " | |
2317 | "from %s (host_reject_connection)", host_and_ident(FALSE)); | |
2318 | smtp_printf("554 SMTP service not available\r\n"); | |
2319 | return FALSE; | |
2320 | } | |
2321 | ||
afb3eaaf PH |
2322 | /* Test with TCP Wrappers if so configured. There is a problem in that |
2323 | hosts_ctl() returns 0 (deny) under a number of system failure circumstances, | |
2324 | such as disks dying. In these cases, it is desirable to reject with a 4xx | |
2325 | error instead of a 5xx error. There isn't a "right" way to detect such | |
2326 | problems. The following kludge is used: errno is zeroed before calling | |
2327 | hosts_ctl(). If the result is "reject", a 5xx error is given only if the | |
2328 | value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does | |
2329 | not exist). */ | |
059ec3d9 PH |
2330 | |
2331 | #ifdef USE_TCP_WRAPPERS | |
afb3eaaf | 2332 | errno = 0; |
5dc43717 JJ |
2333 | tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name); |
2334 | if (tcp_wrappers_name == NULL) | |
2335 | { | |
2336 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" " | |
2337 | "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name), | |
2338 | expand_string_message); | |
2339 | } | |
2340 | if (!hosts_ctl(tcp_wrappers_name, | |
059ec3d9 PH |
2341 | (sender_host_name == NULL)? STRING_UNKNOWN : CS sender_host_name, |
2342 | (sender_host_address == NULL)? STRING_UNKNOWN : CS sender_host_address, | |
2343 | (sender_ident == NULL)? STRING_UNKNOWN : CS sender_ident)) | |
2344 | { | |
afb3eaaf PH |
2345 | if (errno == 0 || errno == ENOENT) |
2346 | { | |
2347 | HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n"); | |
2348 | log_write(L_connection_reject, | |
2349 | LOG_MAIN|LOG_REJECT, "refused connection from %s " | |
2350 | "(tcp wrappers)", host_and_ident(FALSE)); | |
2351 | smtp_printf("554 SMTP service not available\r\n"); | |
2352 | } | |
2353 | else | |
2354 | { | |
2355 | int save_errno = errno; | |
2356 | HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected " | |
2357 | "errno value %d\n", save_errno); | |
2358 | log_write(L_connection_reject, | |
2359 | LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s " | |
2360 | "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno); | |
2361 | smtp_printf("451 Temporary local problem - please try later\r\n"); | |
2362 | } | |
059ec3d9 PH |
2363 | return FALSE; |
2364 | } | |
2365 | #endif | |
2366 | ||
b01dd148 PH |
2367 | /* Check for reserved slots. The value of smtp_accept_count has already been |
2368 | incremented to include this process. */ | |
059ec3d9 PH |
2369 | |
2370 | if (smtp_accept_max > 0 && | |
b01dd148 | 2371 | smtp_accept_count > smtp_accept_max - smtp_accept_reserve) |
059ec3d9 PH |
2372 | { |
2373 | if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK) | |
2374 | { | |
2375 | log_write(L_connection_reject, | |
2376 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2377 | "reserve list: connected=%d max=%d reserve=%d%s", | |
b01dd148 | 2378 | host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max, |
059ec3d9 PH |
2379 | smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : ""); |
2380 | smtp_printf("421 %s: Too many concurrent SMTP connections; " | |
2381 | "please try again later\r\n", smtp_active_hostname); | |
2382 | return FALSE; | |
2383 | } | |
2384 | reserved_host = TRUE; | |
2385 | } | |
2386 | ||
2387 | /* If a load level above which only messages from reserved hosts are | |
2388 | accepted is set, check the load. For incoming calls via the daemon, the | |
2389 | check is done in the superior process if there are no reserved hosts, to | |
2390 | save a fork. In all cases, the load average will already be available | |
2391 | in a global variable at this point. */ | |
2392 | ||
2393 | if (smtp_load_reserve >= 0 && | |
2394 | load_average > smtp_load_reserve && | |
2395 | !reserved_host && | |
2396 | verify_check_host(&smtp_reserve_hosts) != OK) | |
2397 | { | |
2398 | log_write(L_connection_reject, | |
2399 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2400 | "reserve list and load average = %.2f", host_and_ident(FALSE), | |
2401 | (double)load_average/1000.0); | |
2402 | smtp_printf("421 %s: Too much load; please try again later\r\n", | |
2403 | smtp_active_hostname); | |
2404 | return FALSE; | |
2405 | } | |
2406 | ||
2407 | /* Determine whether unqualified senders or recipients are permitted | |
2408 | for this host. Unfortunately, we have to do this every time, in order to | |
2409 | set the flags so that they can be inspected when considering qualifying | |
2410 | addresses in the headers. For a site that permits no qualification, this | |
2411 | won't take long, however. */ | |
2412 | ||
2413 | allow_unqualified_sender = | |
2414 | verify_check_host(&sender_unqualified_hosts) == OK; | |
2415 | ||
2416 | allow_unqualified_recipient = | |
2417 | verify_check_host(&recipient_unqualified_hosts) == OK; | |
2418 | ||
2419 | /* Determine whether HELO/EHLO is required for this host. The requirement | |
2420 | can be hard or soft. */ | |
2421 | ||
2422 | helo_required = verify_check_host(&helo_verify_hosts) == OK; | |
2423 | if (!helo_required) | |
2424 | helo_verify = verify_check_host(&helo_try_verify_hosts) == OK; | |
2425 | ||
2426 | /* Determine whether this hosts is permitted to send syntactic junk | |
2427 | after a HELO or EHLO command. */ | |
2428 | ||
2429 | helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK; | |
2430 | } | |
2431 | ||
2432 | /* For batch SMTP input we are now done. */ | |
2433 | ||
2434 | if (smtp_batched_input) return TRUE; | |
2435 | ||
cee5f132 | 2436 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
2437 | /* If valid Proxy Protocol source is connecting, set up session. |
2438 | * Failure will not allow any SMTP function other than QUIT. */ | |
2439 | proxy_session = FALSE; | |
2440 | proxy_session_failed = FALSE; | |
2441 | if (check_proxy_protocol_host()) | |
2442 | { | |
2443 | if (setup_proxy_protocol_host() == FALSE) | |
2444 | { | |
2445 | proxy_session_failed = TRUE; | |
2446 | DEBUG(D_receive) | |
2447 | debug_printf("Failure to extract proxied host, only QUIT allowed\n"); | |
2448 | } | |
2449 | else | |
2450 | { | |
2451 | sender_host_name = NULL; | |
2452 | (void)host_name_lookup(); | |
2453 | host_build_sender_fullhost(); | |
2454 | } | |
2455 | } | |
2456 | #endif | |
2457 | ||
059ec3d9 PH |
2458 | /* Run the ACL if it exists */ |
2459 | ||
4e88a19f | 2460 | user_msg = NULL; |
059ec3d9 PH |
2461 | if (acl_smtp_connect != NULL) |
2462 | { | |
2463 | int rc; | |
64ffc24f | 2464 | rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg, |
059ec3d9 PH |
2465 | &log_msg); |
2466 | if (rc != OK) | |
2467 | { | |
2468 | (void)smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg); | |
2469 | return FALSE; | |
2470 | } | |
2471 | } | |
2472 | ||
2473 | /* Output the initial message for a two-way SMTP connection. It may contain | |
2474 | newlines, which then cause a multi-line response to be given. */ | |
2475 | ||
4e88a19f PH |
2476 | code = US"220"; /* Default status code */ |
2477 | esc = US""; /* Default extended status code */ | |
2478 | esclen = 0; /* Length of esc */ | |
2479 | ||
d4ff61d1 | 2480 | if (!user_msg) |
4e88a19f | 2481 | { |
d4ff61d1 | 2482 | if (!(s = expand_string(smtp_banner))) |
4e88a19f PH |
2483 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) " |
2484 | "failed: %s", smtp_banner, expand_string_message); | |
2485 | } | |
2486 | else | |
2487 | { | |
2488 | int codelen = 3; | |
2489 | s = user_msg; | |
4f6ae5c3 | 2490 | smtp_message_code(&code, &codelen, &s, NULL, TRUE); |
d6a96edc | 2491 | if (codelen > 4) |
4e88a19f PH |
2492 | { |
2493 | esc = code + 4; | |
2494 | esclen = codelen - 4; | |
2495 | } | |
2496 | } | |
059ec3d9 PH |
2497 | |
2498 | /* Remove any terminating newlines; might as well remove trailing space too */ | |
2499 | ||
2500 | p = s + Ustrlen(s); | |
2501 | while (p > s && isspace(p[-1])) p--; | |
2502 | *p = 0; | |
2503 | ||
2504 | /* It seems that CC:Mail is braindead, and assumes that the greeting message | |
2505 | is all contained in a single IP packet. The original code wrote out the | |
2506 | greeting using several calls to fprint/fputc, and on busy servers this could | |
2507 | cause it to be split over more than one packet - which caused CC:Mail to fall | |
2508 | over when it got the second part of the greeting after sending its first | |
2509 | command. Sigh. To try to avoid this, build the complete greeting message | |
2510 | first, and output it in one fell swoop. This gives a better chance of it | |
2511 | ending up as a single packet. */ | |
2512 | ||
2513 | ss = store_get(size); | |
2514 | ptr = 0; | |
2515 | ||
2516 | p = s; | |
2517 | do /* At least once, in case we have an empty string */ | |
2518 | { | |
2519 | int len; | |
2520 | uschar *linebreak = Ustrchr(p, '\n'); | |
c2f669a4 | 2521 | ss = string_catn(ss, &size, &ptr, code, 3); |
059ec3d9 PH |
2522 | if (linebreak == NULL) |
2523 | { | |
2524 | len = Ustrlen(p); | |
c2f669a4 | 2525 | ss = string_catn(ss, &size, &ptr, US" ", 1); |
059ec3d9 PH |
2526 | } |
2527 | else | |
2528 | { | |
2529 | len = linebreak - p; | |
c2f669a4 | 2530 | ss = string_catn(ss, &size, &ptr, US"-", 1); |
059ec3d9 | 2531 | } |
c2f669a4 JH |
2532 | ss = string_catn(ss, &size, &ptr, esc, esclen); |
2533 | ss = string_catn(ss, &size, &ptr, p, len); | |
2534 | ss = string_catn(ss, &size, &ptr, US"\r\n", 2); | |
059ec3d9 PH |
2535 | p += len; |
2536 | if (linebreak != NULL) p++; | |
2537 | } | |
2538 | while (*p != 0); | |
2539 | ||
2540 | ss[ptr] = 0; /* string_cat leaves room for this */ | |
2541 | ||
2542 | /* Before we write the banner, check that there is no input pending, unless | |
2543 | this synchronisation check is disabled. */ | |
2544 | ||
a14e5636 | 2545 | if (!check_sync()) |
059ec3d9 | 2546 | { |
a14e5636 PH |
2547 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol " |
2548 | "synchronization error (input sent without waiting for greeting): " | |
2549 | "rejected connection from %s input=\"%s\"", host_and_ident(TRUE), | |
2550 | string_printing(smtp_inptr)); | |
2551 | smtp_printf("554 SMTP synchronization error\r\n"); | |
2552 | return FALSE; | |
059ec3d9 PH |
2553 | } |
2554 | ||
2555 | /* Now output the banner */ | |
2556 | ||
2557 | smtp_printf("%s", ss); | |
2558 | return TRUE; | |
2559 | } | |
2560 | ||
2561 | ||
2562 | ||
2563 | ||
2564 | ||
2565 | /************************************************* | |
2566 | * Handle SMTP syntax and protocol errors * | |
2567 | *************************************************/ | |
2568 | ||
2569 | /* Write to the log for SMTP syntax errors in incoming commands, if configured | |
2570 | to do so. Then transmit the error response. The return value depends on the | |
2571 | number of syntax and protocol errors in this SMTP session. | |
2572 | ||
2573 | Arguments: | |
2574 | type error type, given as a log flag bit | |
2575 | code response code; <= 0 means don't send a response | |
2576 | data data to reflect in the response (can be NULL) | |
2577 | errmess the error message | |
2578 | ||
2579 | Returns: -1 limit of syntax/protocol errors NOT exceeded | |
2580 | +1 limit of syntax/protocol errors IS exceeded | |
2581 | ||
2582 | These values fit in with the values of the "done" variable in the main | |
2583 | processing loop in smtp_setup_msg(). */ | |
2584 | ||
2585 | static int | |
2586 | synprot_error(int type, int code, uschar *data, uschar *errmess) | |
2587 | { | |
2588 | int yield = -1; | |
2589 | ||
2590 | log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s", | |
2591 | (type == L_smtp_syntax_error)? "syntax" : "protocol", | |
3ee512ff | 2592 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess); |
059ec3d9 PH |
2593 | |
2594 | if (++synprot_error_count > smtp_max_synprot_errors) | |
2595 | { | |
2596 | yield = 1; | |
2597 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
2598 | "syntax or protocol errors (last command was \"%s\")", | |
0ebc4d69 | 2599 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
2600 | } |
2601 | ||
2602 | if (code > 0) | |
2603 | { | |
2604 | smtp_printf("%d%c%s%s%s\r\n", code, (yield == 1)? '-' : ' ', | |
2605 | (data == NULL)? US"" : data, (data == NULL)? US"" : US": ", errmess); | |
2606 | if (yield == 1) | |
2607 | smtp_printf("%d Too many syntax or protocol errors\r\n", code); | |
2608 | } | |
2609 | ||
2610 | return yield; | |
2611 | } | |
2612 | ||
2613 | ||
2614 | ||
2615 | ||
2616 | /************************************************* | |
2617 | * Log incomplete transactions * | |
2618 | *************************************************/ | |
2619 | ||
2620 | /* This function is called after a transaction has been aborted by RSET, QUIT, | |
2621 | connection drops or other errors. It logs the envelope information received | |
2622 | so far in order to preserve address verification attempts. | |
2623 | ||
2624 | Argument: string to indicate what aborted the transaction | |
2625 | Returns: nothing | |
2626 | */ | |
2627 | ||
2628 | static void | |
2629 | incomplete_transaction_log(uschar *what) | |
2630 | { | |
2631 | if (sender_address == NULL || /* No transaction in progress */ | |
6c6d6e48 TF |
2632 | !LOGGING(smtp_incomplete_transaction)) |
2633 | return; | |
059ec3d9 PH |
2634 | |
2635 | /* Build list of recipients for logging */ | |
2636 | ||
2637 | if (recipients_count > 0) | |
2638 | { | |
2639 | int i; | |
2640 | raw_recipients = store_get(recipients_count * sizeof(uschar *)); | |
2641 | for (i = 0; i < recipients_count; i++) | |
2642 | raw_recipients[i] = recipients_list[i].address; | |
2643 | raw_recipients_count = recipients_count; | |
2644 | } | |
2645 | ||
2646 | log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS, | |
2647 | "%s incomplete transaction (%s)", host_and_ident(TRUE), what); | |
2648 | } | |
2649 | ||
2650 | ||
2651 | ||
2652 | ||
2653 | /************************************************* | |
2654 | * Send SMTP response, possibly multiline * | |
2655 | *************************************************/ | |
2656 | ||
2657 | /* There are, it seems, broken clients out there that cannot handle multiline | |
2658 | responses. If no_multiline_responses is TRUE (it can be set from an ACL), we | |
2659 | output nothing for non-final calls, and only the first line for anything else. | |
2660 | ||
2661 | Arguments: | |
a5bd321b | 2662 | code SMTP code, may involve extended status codes |
d6a96edc | 2663 | codelen length of smtp code; if > 4 there's an ESC |
059ec3d9 PH |
2664 | final FALSE if the last line isn't the final line |
2665 | msg message text, possibly containing newlines | |
2666 | ||
2667 | Returns: nothing | |
2668 | */ | |
2669 | ||
2670 | void | |
a5bd321b | 2671 | smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg) |
059ec3d9 | 2672 | { |
a5bd321b PH |
2673 | int esclen = 0; |
2674 | uschar *esc = US""; | |
2675 | ||
059ec3d9 PH |
2676 | if (!final && no_multiline_responses) return; |
2677 | ||
d6a96edc | 2678 | if (codelen > 4) |
a5bd321b PH |
2679 | { |
2680 | esc = code + 4; | |
2681 | esclen = codelen - 4; | |
2682 | } | |
2683 | ||
2679d413 PH |
2684 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs |
2685 | have had the same. Note: this code is also present in smtp_printf(). It would | |
2686 | be tidier to have it only in one place, but when it was added, it was easier to | |
2687 | do it that way, so as not to have to mess with the code for the RCPT command, | |
2688 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
2689 | ||
2690 | if (rcpt_in_progress) | |
2691 | { | |
2692 | if (rcpt_smtp_response == NULL) | |
2693 | rcpt_smtp_response = string_copy(msg); | |
2694 | else if (rcpt_smtp_response_same && | |
2695 | Ustrcmp(rcpt_smtp_response, msg) != 0) | |
2696 | rcpt_smtp_response_same = FALSE; | |
2697 | rcpt_in_progress = FALSE; | |
2698 | } | |
2699 | ||
2700 | /* Not output the message, splitting it up into multiple lines if necessary. */ | |
2701 | ||
059ec3d9 PH |
2702 | for (;;) |
2703 | { | |
2704 | uschar *nl = Ustrchr(msg, '\n'); | |
2705 | if (nl == NULL) | |
2706 | { | |
a5bd321b | 2707 | smtp_printf("%.3s%c%.*s%s\r\n", code, final? ' ':'-', esclen, esc, msg); |
059ec3d9 PH |
2708 | return; |
2709 | } | |
2710 | else if (nl[1] == 0 || no_multiline_responses) | |
2711 | { | |
a5bd321b PH |
2712 | smtp_printf("%.3s%c%.*s%.*s\r\n", code, final? ' ':'-', esclen, esc, |
2713 | (int)(nl - msg), msg); | |
059ec3d9 PH |
2714 | return; |
2715 | } | |
2716 | else | |
2717 | { | |
a5bd321b | 2718 | smtp_printf("%.3s-%.*s%.*s\r\n", code, esclen, esc, (int)(nl - msg), msg); |
059ec3d9 PH |
2719 | msg = nl + 1; |
2720 | while (isspace(*msg)) msg++; | |
2721 | } | |
2722 | } | |
2723 | } | |
2724 | ||
2725 | ||
2726 | ||
2727 | ||
4e88a19f PH |
2728 | /************************************************* |
2729 | * Parse user SMTP message * | |
2730 | *************************************************/ | |
2731 | ||
2732 | /* This function allows for user messages overriding the response code details | |
2733 | by providing a suitable response code string at the start of the message | |
2734 | user_msg. Check the message for starting with a response code and optionally an | |
2735 | extended status code. If found, check that the first digit is valid, and if so, | |
2736 | change the code pointer and length to use the replacement. An invalid code | |
2737 | causes a panic log; in this case, if the log messages is the same as the user | |
2738 | message, we must also adjust the value of the log message to show the code that | |
2739 | is actually going to be used (the original one). | |
2740 | ||
2741 | This function is global because it is called from receive.c as well as within | |
2742 | this module. | |
2743 | ||
d6a96edc PH |
2744 | Note that the code length returned includes the terminating whitespace |
2745 | character, which is always included in the regex match. | |
2746 | ||
4e88a19f PH |
2747 | Arguments: |
2748 | code SMTP code, may involve extended status codes | |
d6a96edc | 2749 | codelen length of smtp code; if > 4 there's an ESC |
4e88a19f PH |
2750 | msg message text |
2751 | log_msg optional log message, to be adjusted with the new SMTP code | |
4f6ae5c3 | 2752 | check_valid if true, verify the response code |
4e88a19f PH |
2753 | |
2754 | Returns: nothing | |
2755 | */ | |
2756 | ||
2757 | void | |
4f6ae5c3 JH |
2758 | smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg, |
2759 | BOOL check_valid) | |
4e88a19f PH |
2760 | { |
2761 | int n; | |
2762 | int ovector[3]; | |
2763 | ||
4f6ae5c3 | 2764 | if (!msg || !*msg) return; |
4e88a19f | 2765 | |
4f6ae5c3 JH |
2766 | if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0, |
2767 | PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return; | |
4e88a19f | 2768 | |
4f6ae5c3 | 2769 | if (check_valid && (*msg)[0] != (*code)[0]) |
4e88a19f PH |
2770 | { |
2771 | log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with " | |
2772 | "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg); | |
2773 | if (log_msg != NULL && *log_msg == *msg) | |
2774 | *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]); | |
2775 | } | |
2776 | else | |
2777 | { | |
2778 | *code = *msg; | |
2779 | *codelen = ovector[1]; /* Includes final space */ | |
2780 | } | |
2781 | *msg += ovector[1]; /* Chop the code off the message */ | |
2782 | return; | |
2783 | } | |
2784 | ||
2785 | ||
2786 | ||
2787 | ||
059ec3d9 PH |
2788 | /************************************************* |
2789 | * Handle an ACL failure * | |
2790 | *************************************************/ | |
2791 | ||
2792 | /* This function is called when acl_check() fails. As well as calls from within | |
2793 | this module, it is called from receive.c for an ACL after DATA. It sorts out | |
2794 | logging the incident, and sets up the error response. A message containing | |
2795 | newlines is turned into a multiline SMTP response, but for logging, only the | |
2796 | first line is used. | |
2797 | ||
a5bd321b PH |
2798 | There's a table of default permanent failure response codes to use in |
2799 | globals.c, along with the table of names. VFRY is special. Despite RFC1123 it | |
2800 | defaults disabled in Exim. However, discussion in connection with RFC 821bis | |
2801 | (aka RFC 2821) has concluded that the response should be 252 in the disabled | |
2802 | state, because there are broken clients that try VRFY before RCPT. A 5xx | |
2803 | response should be given only when the address is positively known to be | |
4f6ae5c3 JH |
2804 | undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides |
2805 | no explicit code, but if there is one we let it know best. | |
2806 | Also, for ETRN, 458 is given on refusal, and for AUTH, 503. | |
a5bd321b PH |
2807 | |
2808 | From Exim 4.63, it is possible to override the response code details by | |
2809 | providing a suitable response code string at the start of the message provided | |
2810 | in user_msg. The code's first digit is checked for validity. | |
059ec3d9 PH |
2811 | |
2812 | Arguments: | |
4f6ae5c3 JH |
2813 | where where the ACL was called from |
2814 | rc the failure code | |
2815 | user_msg a message that can be included in an SMTP response | |
2816 | log_msg a message for logging | |
059ec3d9 PH |
2817 | |
2818 | Returns: 0 in most cases | |
2819 | 2 if the failure code was FAIL_DROP, in which case the | |
2820 | SMTP connection should be dropped (this value fits with the | |
2821 | "done" variable in smtp_setup_msg() below) | |
2822 | */ | |
2823 | ||
2824 | int | |
2825 | smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg) | |
2826 | { | |
059ec3d9 | 2827 | BOOL drop = rc == FAIL_DROP; |
a5bd321b | 2828 | int codelen = 3; |
a5bd321b | 2829 | uschar *smtp_code; |
059ec3d9 PH |
2830 | uschar *lognl; |
2831 | uschar *sender_info = US""; | |
64ffc24f | 2832 | uschar *what = |
8523533c | 2833 | #ifdef WITH_CONTENT_SCAN |
64ffc24f | 2834 | (where == ACL_WHERE_MIME)? US"during MIME ACL checks" : |
8e669ac1 | 2835 | #endif |
64ffc24f PH |
2836 | (where == ACL_WHERE_PREDATA)? US"DATA" : |
2837 | (where == ACL_WHERE_DATA)? US"after DATA" : | |
8ccd00b1 | 2838 | #ifndef DISABLE_PRDR |
fd98a5c6 JH |
2839 | (where == ACL_WHERE_PRDR)? US"after DATA PRDR" : |
2840 | #endif | |
ca86f471 | 2841 | (smtp_cmd_data == NULL)? |
64ffc24f | 2842 | string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) : |
ca86f471 | 2843 | string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data); |
059ec3d9 PH |
2844 | |
2845 | if (drop) rc = FAIL; | |
2846 | ||
4e88a19f | 2847 | /* Set the default SMTP code, and allow a user message to change it. */ |
a5bd321b | 2848 | |
4f6ae5c3 JH |
2849 | smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451"; |
2850 | smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg, | |
2851 | where != ACL_WHERE_VRFY); | |
a5bd321b | 2852 | |
059ec3d9 PH |
2853 | /* We used to have sender_address here; however, there was a bug that was not |
2854 | updating sender_address after a rewrite during a verify. When this bug was | |
2855 | fixed, sender_address at this point became the rewritten address. I'm not sure | |
2856 | this is what should be logged, so I've changed to logging the unrewritten | |
2857 | address to retain backward compatibility. */ | |
2858 | ||
8523533c | 2859 | #ifndef WITH_CONTENT_SCAN |
059ec3d9 | 2860 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA) |
8523533c TK |
2861 | #else |
2862 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME) | |
2863 | #endif | |
059ec3d9 | 2864 | { |
b98bb9ac PP |
2865 | sender_info = string_sprintf("F=<%s>%s%s%s%s ", |
2866 | sender_address_unrewritten ? sender_address_unrewritten : sender_address, | |
2867 | sender_host_authenticated ? US" A=" : US"", | |
2868 | sender_host_authenticated ? sender_host_authenticated : US"", | |
2869 | sender_host_authenticated && authenticated_id ? US":" : US"", | |
2870 | sender_host_authenticated && authenticated_id ? authenticated_id : US"" | |
2871 | ); | |
059ec3d9 PH |
2872 | } |
2873 | ||
2874 | /* If there's been a sender verification failure with a specific message, and | |
2875 | we have not sent a response about it yet, do so now, as a preliminary line for | |
278c6e6c PH |
2876 | failures, but not defers. However, always log it for defer, and log it for fail |
2877 | unless the sender_verify_fail log selector has been turned off. */ | |
059ec3d9 PH |
2878 | |
2879 | if (sender_verified_failed != NULL && | |
2880 | !testflag(sender_verified_failed, af_sverify_told)) | |
2881 | { | |
2679d413 PH |
2882 | BOOL save_rcpt_in_progress = rcpt_in_progress; |
2883 | rcpt_in_progress = FALSE; /* So as not to treat these as the error */ | |
2884 | ||
059ec3d9 PH |
2885 | setflag(sender_verified_failed, af_sverify_told); |
2886 | ||
6c6d6e48 | 2887 | if (rc != FAIL || LOGGING(sender_verify_fail)) |
278c6e6c PH |
2888 | log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s", |
2889 | host_and_ident(TRUE), | |
2890 | ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail", | |
2891 | sender_verified_failed->address, | |
2892 | (sender_verified_failed->message == NULL)? US"" : | |
2893 | string_sprintf(": %s", sender_verified_failed->message)); | |
059ec3d9 PH |
2894 | |
2895 | if (rc == FAIL && sender_verified_failed->user_message != NULL) | |
a5bd321b | 2896 | smtp_respond(smtp_code, codelen, FALSE, string_sprintf( |
059ec3d9 PH |
2897 | testflag(sender_verified_failed, af_verify_pmfail)? |
2898 | "Postmaster verification failed while checking <%s>\n%s\n" | |
2899 | "Several RFCs state that you are required to have a postmaster\n" | |
2900 | "mailbox for each mail domain. This host does not accept mail\n" | |
2901 | "from domains whose servers reject the postmaster address." | |
2902 | : | |
2903 | testflag(sender_verified_failed, af_verify_nsfail)? | |
2904 | "Callback setup failed while verifying <%s>\n%s\n" | |
2905 | "The initial connection, or a HELO or MAIL FROM:<> command was\n" | |
2906 | "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n" | |
2907 | "RFC requirements, and stops you from receiving standard bounce\n" | |
2908 | "messages. This host does not accept mail from domains whose servers\n" | |
2909 | "refuse bounces." | |
2910 | : | |
2911 | "Verification failed for <%s>\n%s", | |
2912 | sender_verified_failed->address, | |
2913 | sender_verified_failed->user_message)); | |
2679d413 PH |
2914 | |
2915 | rcpt_in_progress = save_rcpt_in_progress; | |
059ec3d9 PH |
2916 | } |
2917 | ||
2918 | /* Sort out text for logging */ | |
2919 | ||
2920 | log_msg = (log_msg == NULL)? US"" : string_sprintf(": %s", log_msg); | |
2921 | lognl = Ustrchr(log_msg, '\n'); | |
2922 | if (lognl != NULL) *lognl = 0; | |
2923 | ||
2924 | /* Send permanent failure response to the command, but the code used isn't | |
2925 | always a 5xx one - see comments at the start of this function. If the original | |
2926 | rc was FAIL_DROP we drop the connection and yield 2. */ | |
2927 | ||
a5bd321b | 2928 | if (rc == FAIL) smtp_respond(smtp_code, codelen, TRUE, (user_msg == NULL)? |
059ec3d9 PH |
2929 | US"Administrative prohibition" : user_msg); |
2930 | ||
2931 | /* Send temporary failure response to the command. Don't give any details, | |
2932 | unless acl_temp_details is set. This is TRUE for a callout defer, a "defer" | |
2933 | verb, and for a header verify when smtp_return_error_details is set. | |
2934 | ||
2935 | This conditional logic is all somewhat of a mess because of the odd | |
2936 | interactions between temp_details and return_error_details. One day it should | |
2937 | be re-implemented in a tidier fashion. */ | |
2938 | ||
2939 | else | |
2940 | { | |
2941 | if (acl_temp_details && user_msg != NULL) | |
2942 | { | |
2943 | if (smtp_return_error_details && | |
2944 | sender_verified_failed != NULL && | |
2945 | sender_verified_failed->message != NULL) | |
2946 | { | |
a5bd321b | 2947 | smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message); |
059ec3d9 | 2948 | } |
a5bd321b | 2949 | smtp_respond(smtp_code, codelen, TRUE, user_msg); |
059ec3d9 PH |
2950 | } |
2951 | else | |
a5bd321b PH |
2952 | smtp_respond(smtp_code, codelen, TRUE, |
2953 | US"Temporary local problem - please try later"); | |
059ec3d9 PH |
2954 | } |
2955 | ||
6ea85e9a PH |
2956 | /* Log the incident to the logs that are specified by log_reject_target |
2957 | (default main, reject). This can be empty to suppress logging of rejections. If | |
2958 | the connection is not forcibly to be dropped, return 0. Otherwise, log why it | |
2959 | is closing if required and return 2. */ | |
059ec3d9 | 2960 | |
6ea85e9a | 2961 | if (log_reject_target != 0) |
887291d2 | 2962 | { |
e45a1c37 | 2963 | #ifdef SUPPORT_TLS |
fc16abb4 JH |
2964 | uschar * tls = s_tlslog(NULL, NULL, NULL); |
2965 | if (!tls) tls = US""; | |
e45a1c37 | 2966 | #else |
fc16abb4 | 2967 | uschar * tls = US""; |
e45a1c37 | 2968 | #endif |
fc16abb4 JH |
2969 | log_write(0, log_reject_target, "%s%s%s %s%srejected %s%s", |
2970 | LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"", | |
2971 | host_and_ident(TRUE), | |
2972 | tls, | |
2973 | sender_info, | |
2974 | rc == FAIL ? US"" : US"temporarily ", | |
2975 | what, log_msg); | |
887291d2 | 2976 | } |
059ec3d9 PH |
2977 | |
2978 | if (!drop) return 0; | |
2979 | ||
2980 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL", | |
2981 | smtp_get_connection_info()); | |
8f128379 PH |
2982 | |
2983 | /* Run the not-quit ACL, but without any custom messages. This should not be a | |
2984 | problem, because we get here only if some other ACL has issued "drop", and | |
2985 | in that case, *its* custom messages will have been used above. */ | |
2986 | ||
2987 | smtp_notquit_exit(US"acl-drop", NULL, NULL); | |
059ec3d9 PH |
2988 | return 2; |
2989 | } | |
2990 | ||
2991 | ||
2992 | ||
2993 | ||
8f128379 PH |
2994 | /************************************************* |
2995 | * Handle SMTP exit when QUIT is not given * | |
2996 | *************************************************/ | |
2997 | ||
2998 | /* This function provides a logging/statistics hook for when an SMTP connection | |
2999 | is dropped on the floor or the other end goes away. It's a global function | |
3000 | because it's called from receive.c as well as this module. As well as running | |
3001 | the NOTQUIT ACL, if there is one, this function also outputs a final SMTP | |
3002 | response, either with a custom message from the ACL, or using a default. There | |
3003 | is one case, however, when no message is output - after "drop". In that case, | |
3004 | the ACL that obeyed "drop" has already supplied the custom message, and NULL is | |
3005 | passed to this function. | |
3006 | ||
3007 | In case things go wrong while processing this function, causing an error that | |
3008 | may re-enter this funtion, there is a recursion check. | |
3009 | ||
3010 | Arguments: | |
3011 | reason What $smtp_notquit_reason will be set to in the ACL; | |
3012 | if NULL, the ACL is not run | |
3013 | code The error code to return as part of the response | |
3014 | defaultrespond The default message if there's no user_msg | |
3015 | ||
3016 | Returns: Nothing | |
3017 | */ | |
3018 | ||
3019 | void | |
3020 | smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...) | |
3021 | { | |
3022 | int rc; | |
3023 | uschar *user_msg = NULL; | |
3024 | uschar *log_msg = NULL; | |
3025 | ||
3026 | /* Check for recursive acll */ | |
3027 | ||
3028 | if (smtp_exit_function_called) | |
3029 | { | |
3030 | log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)", | |
3031 | reason); | |
3032 | return; | |
3033 | } | |
3034 | smtp_exit_function_called = TRUE; | |
3035 | ||
3036 | /* Call the not-QUIT ACL, if there is one, unless no reason is given. */ | |
3037 | ||
3038 | if (acl_smtp_notquit != NULL && reason != NULL) | |
3039 | { | |
3040 | smtp_notquit_reason = reason; | |
3041 | rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg, | |
3042 | &log_msg); | |
3043 | if (rc == ERROR) | |
3044 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s", | |
3045 | log_msg); | |
3046 | } | |
3047 | ||
3048 | /* Write an SMTP response if we are expected to give one. As the default | |
3049 | responses are all internal, they should always fit in the buffer, but code a | |
3050 | warning, just in case. Note that string_vformat() still leaves a complete | |
3051 | string, even if it is incomplete. */ | |
3052 | ||
3053 | if (code != NULL && defaultrespond != NULL) | |
3054 | { | |
3055 | if (user_msg == NULL) | |
3056 | { | |
3057 | uschar buffer[128]; | |
3058 | va_list ap; | |
3059 | va_start(ap, defaultrespond); | |
3060 | if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap)) | |
3061 | log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()"); | |
3062 | smtp_printf("%s %s\r\n", code, buffer); | |
3063 | va_end(ap); | |
3064 | } | |
3065 | else | |
3066 | smtp_respond(code, 3, TRUE, user_msg); | |
3067 | mac_smtp_fflush(); | |
3068 | } | |
3069 | } | |
3070 | ||
3071 | ||
3072 | ||
3073 | ||
d7b47fd0 PH |
3074 | /************************************************* |
3075 | * Verify HELO argument * | |
3076 | *************************************************/ | |
3077 | ||
3078 | /* This function is called if helo_verify_hosts or helo_try_verify_hosts is | |
3079 | matched. It is also called from ACL processing if verify = helo is used and | |
3080 | verification was not previously tried (i.e. helo_try_verify_hosts was not | |
3081 | matched). The result of its processing is to set helo_verified and | |
3082 | helo_verify_failed. These variables should both be FALSE for this function to | |
3083 | be called. | |
3084 | ||
3085 | Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow | |
3086 | for IPv6 ::ffff: literals. | |
3087 | ||
3088 | Argument: none | |
3089 | Returns: TRUE if testing was completed; | |
3090 | FALSE on a temporary failure | |
3091 | */ | |
3092 | ||
3093 | BOOL | |
3094 | smtp_verify_helo(void) | |
3095 | { | |
3096 | BOOL yield = TRUE; | |
3097 | ||
3098 | HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n", | |
3099 | sender_helo_name); | |
3100 | ||
3101 | if (sender_helo_name == NULL) | |
3102 | { | |
3103 | HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n"); | |
3104 | } | |
3105 | ||
d1d5595c PH |
3106 | /* Deal with the case of -bs without an IP address */ |
3107 | ||
3108 | else if (sender_host_address == NULL) | |
3109 | { | |
3110 | HDEBUG(D_receive) debug_printf("no client IP address: assume success\n"); | |
3111 | helo_verified = TRUE; | |
3112 | } | |
3113 | ||
3114 | /* Deal with the more common case when there is a sending IP address */ | |
3115 | ||
d7b47fd0 PH |
3116 | else if (sender_helo_name[0] == '[') |
3117 | { | |
3118 | helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address, | |
3119 | Ustrlen(sender_host_address)) == 0; | |
3120 | ||
3121 | #if HAVE_IPV6 | |
3122 | if (!helo_verified) | |
3123 | { | |
3124 | if (strncmpic(sender_host_address, US"::ffff:", 7) == 0) | |
3125 | helo_verified = Ustrncmp(sender_helo_name + 1, | |
3126 | sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0; | |
3127 | } | |
3128 | #endif | |
3129 | ||
3130 | HDEBUG(D_receive) | |
3131 | { if (helo_verified) debug_printf("matched host address\n"); } | |
3132 | } | |
3133 | ||
3134 | /* Do a reverse lookup if one hasn't already given a positive or negative | |
3135 | response. If that fails, or the name doesn't match, try checking with a forward | |
3136 | lookup. */ | |
3137 | ||
3138 | else | |
3139 | { | |
3140 | if (sender_host_name == NULL && !host_lookup_failed) | |
3141 | yield = host_name_lookup() != DEFER; | |
3142 | ||
3143 | /* If a host name is known, check it and all its aliases. */ | |
3144 | ||
1705dd20 JH |
3145 | if (sender_host_name) |
3146 | if ((helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0)) | |
d7b47fd0 | 3147 | { |
1705dd20 | 3148 | sender_helo_dnssec = sender_host_dnssec; |
d7b47fd0 PH |
3149 | HDEBUG(D_receive) debug_printf("matched host name\n"); |
3150 | } | |
3151 | else | |
3152 | { | |
3153 | uschar **aliases = sender_host_aliases; | |
1705dd20 JH |
3154 | while (*aliases) |
3155 | if ((helo_verified = strcmpic(*aliases++, sender_helo_name) == 0)) | |
3156 | { | |
3157 | sender_helo_dnssec = sender_host_dnssec; | |
3158 | break; | |
3159 | } | |
3160 | ||
3161 | HDEBUG(D_receive) if (helo_verified) | |
d7b47fd0 | 3162 | debug_printf("matched alias %s\n", *(--aliases)); |
d7b47fd0 | 3163 | } |
d7b47fd0 PH |
3164 | |
3165 | /* Final attempt: try a forward lookup of the helo name */ | |
3166 | ||
3167 | if (!helo_verified) | |
3168 | { | |
3169 | int rc; | |
3170 | host_item h; | |
1705dd20 JH |
3171 | dnssec_domains d; |
3172 | host_item *hh; | |
3173 | ||
d7b47fd0 PH |
3174 | h.name = sender_helo_name; |
3175 | h.address = NULL; | |
3176 | h.mx = MX_NONE; | |
3177 | h.next = NULL; | |
1705dd20 JH |
3178 | d.request = US"*"; |
3179 | d.require = US""; | |
3180 | ||
d7b47fd0 PH |
3181 | HDEBUG(D_receive) debug_printf("getting IP address for %s\n", |
3182 | sender_helo_name); | |
1705dd20 JH |
3183 | rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A, |
3184 | NULL, NULL, NULL, &d, NULL, NULL); | |
d7b47fd0 | 3185 | if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL) |
1705dd20 | 3186 | for (hh = &h; hh; hh = hh->next) |
d7b47fd0 PH |
3187 | if (Ustrcmp(hh->address, sender_host_address) == 0) |
3188 | { | |
3189 | helo_verified = TRUE; | |
1705dd20 | 3190 | if (h.dnssec == DS_YES) sender_helo_dnssec = TRUE; |
d7b47fd0 | 3191 | HDEBUG(D_receive) |
1705dd20 JH |
3192 | { |
3193 | debug_printf("IP address for %s matches calling address\n" | |
3194 | "Forward DNS security status: %sverified\n", | |
3195 | sender_helo_name, sender_helo_dnssec ? "" : "un"); | |
3196 | } | |
d7b47fd0 PH |
3197 | break; |
3198 | } | |
d7b47fd0 PH |
3199 | } |
3200 | } | |
3201 | ||
d1d5595c | 3202 | if (!helo_verified) helo_verify_failed = TRUE; /* We've tried ... */ |
d7b47fd0 PH |
3203 | return yield; |
3204 | } | |
3205 | ||
3206 | ||
3207 | ||
3208 | ||
4e88a19f PH |
3209 | /************************************************* |
3210 | * Send user response message * | |
3211 | *************************************************/ | |
3212 | ||
3213 | /* This function is passed a default response code and a user message. It calls | |
3214 | smtp_message_code() to check and possibly modify the response code, and then | |
3215 | calls smtp_respond() to transmit the response. I put this into a function | |
3216 | just to avoid a lot of repetition. | |
3217 | ||
3218 | Arguments: | |
3219 | code the response code | |
3220 | user_msg the user message | |
3221 | ||
3222 | Returns: nothing | |
3223 | */ | |
3224 | ||
3225 | static void | |
3226 | smtp_user_msg(uschar *code, uschar *user_msg) | |
3227 | { | |
3228 | int len = 3; | |
4f6ae5c3 | 3229 | smtp_message_code(&code, &len, &user_msg, NULL, TRUE); |
4e88a19f PH |
3230 | smtp_respond(code, len, TRUE, user_msg); |
3231 | } | |
3232 | ||
3233 | ||
3234 | ||
b3ef41c9 JH |
3235 | static int |
3236 | smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss) | |
3237 | { | |
3238 | const uschar *set_id = NULL; | |
3239 | int rc, i; | |
3240 | ||
3241 | /* Run the checking code, passing the remainder of the command line as | |
3242 | data. Initials the $auth<n> variables as empty. Initialize $0 empty and set | |
3243 | it as the only set numerical variable. The authenticator may set $auth<n> | |
3244 | and also set other numeric variables. The $auth<n> variables are preferred | |
3245 | nowadays; the numerical variables remain for backwards compatibility. | |
3246 | ||
3247 | Afterwards, have a go at expanding the set_id string, even if | |
3248 | authentication failed - for bad passwords it can be useful to log the | |
3249 | userid. On success, require set_id to expand and exist, and put it in | |
3250 | authenticated_id. Save this in permanent store, as the working store gets | |
3251 | reset at HELO, RSET, etc. */ | |
3252 | ||
3253 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; | |
3254 | expand_nmax = 0; | |
3255 | expand_nlength[0] = 0; /* $0 contains nothing */ | |
3256 | ||
3257 | rc = (au->info->servercode)(au, smtp_cmd_data); | |
3258 | if (au->set_id) set_id = expand_string(au->set_id); | |
3259 | expand_nmax = -1; /* Reset numeric variables */ | |
3260 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */ | |
3261 | ||
3262 | /* The value of authenticated_id is stored in the spool file and printed in | |
3263 | log lines. It must not contain binary zeros or newline characters. In | |
3264 | normal use, it never will, but when playing around or testing, this error | |
3265 | can (did) happen. To guard against this, ensure that the id contains only | |
3266 | printing characters. */ | |
3267 | ||
3268 | if (set_id) set_id = string_printing(set_id); | |
3269 | ||
3270 | /* For the non-OK cases, set up additional logging data if set_id | |
3271 | is not empty. */ | |
3272 | ||
3273 | if (rc != OK) | |
3274 | set_id = set_id && *set_id | |
3275 | ? string_sprintf(" (set_id=%s)", set_id) : US""; | |
3276 | ||
3277 | /* Switch on the result */ | |
3278 | ||
3279 | switch(rc) | |
3280 | { | |
3281 | case OK: | |
3282 | if (!au->set_id || set_id) /* Complete success */ | |
3283 | { | |
3284 | if (set_id) authenticated_id = string_copy_malloc(set_id); | |
3285 | sender_host_authenticated = au->name; | |
3286 | authentication_failed = FALSE; | |
3287 | authenticated_fail_id = NULL; /* Impossible to already be set? */ | |
3288 | ||
3289 | received_protocol = | |
3290 | (sender_host_address ? protocols : protocols_local) | |
3291 | [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)]; | |
3292 | *s = *ss = US"235 Authentication succeeded"; | |
3293 | authenticated_by = au; | |
3294 | break; | |
3295 | } | |
3296 | ||
3297 | /* Authentication succeeded, but we failed to expand the set_id string. | |
3298 | Treat this as a temporary error. */ | |
3299 | ||
3300 | auth_defer_msg = expand_string_message; | |
3301 | /* Fall through */ | |
3302 | ||
3303 | case DEFER: | |
3304 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3305 | *s = string_sprintf("435 Unable to authenticate at present%s", | |
3306 | auth_defer_user_msg); | |
3307 | *ss = string_sprintf("435 Unable to authenticate at present%s: %s", | |
3308 | set_id, auth_defer_msg); | |
3309 | break; | |
3310 | ||
3311 | case BAD64: | |
3312 | *s = *ss = US"501 Invalid base64 data"; | |
3313 | break; | |
3314 | ||
3315 | case CANCELLED: | |
3316 | *s = *ss = US"501 Authentication cancelled"; | |
3317 | break; | |
3318 | ||
3319 | case UNEXPECTED: | |
3320 | *s = *ss = US"553 Initial data not expected"; | |
3321 | break; | |
3322 | ||
3323 | case FAIL: | |
3324 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3325 | *s = US"535 Incorrect authentication data"; | |
3326 | *ss = string_sprintf("535 Incorrect authentication data%s", set_id); | |
3327 | break; | |
3328 | ||
3329 | default: | |
3330 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3331 | *s = US"435 Internal error"; | |
3332 | *ss = string_sprintf("435 Internal error%s: return %d from authentication " | |
3333 | "check", set_id, rc); | |
3334 | break; | |
3335 | } | |
3336 | ||
3337 | return rc; | |
3338 | } | |
3339 | ||
3340 | ||
3341 | ||
2685d6e0 JH |
3342 | |
3343 | ||
3344 | static int | |
3345 | qualify_recipient(uschar ** recipient, uschar * smtp_cmd_data, uschar * tag) | |
3346 | { | |
3347 | int rd; | |
3348 | if (allow_unqualified_recipient || strcmpic(*recipient, US"postmaster") == 0) | |
3349 | { | |
3350 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
3351 | *recipient); | |
3352 | rd = Ustrlen(recipient) + 1; | |
3353 | *recipient = rewrite_address_qualify(*recipient, TRUE); | |
3354 | return rd; | |
3355 | } | |
3356 | smtp_printf("501 %s: recipient address must contain a domain\r\n", | |
3357 | smtp_cmd_data); | |
3358 | log_write(L_smtp_syntax_error, | |
3359 | LOG_MAIN|LOG_REJECT, "unqualified %s rejected: <%s> %s%s", | |
3360 | tag, *recipient, host_and_ident(TRUE), host_lookup_msg); | |
3361 | return 0; | |
3362 | } | |
3363 | ||
3364 | ||
3365 | ||
3366 | ||
7e3ce68e JH |
3367 | static void |
3368 | smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp) | |
3369 | { | |
3370 | HAD(SCH_QUIT); | |
3371 | incomplete_transaction_log(US"QUIT"); | |
3372 | if (acl_smtp_quit != NULL) | |
3373 | { | |
3374 | int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp); | |
3375 | if (rc == ERROR) | |
3376 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
3377 | *log_msgp); | |
3378 | } | |
3379 | if (*user_msgp) | |
3380 | smtp_respond(US"221", 3, TRUE, *user_msgp); | |
3381 | else | |
3382 | smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); | |
3383 | ||
3384 | #ifdef SUPPORT_TLS | |
3385 | tls_close(TRUE, TRUE); | |
3386 | #endif | |
3387 | ||
3388 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", | |
3389 | smtp_get_connection_info()); | |
3390 | } | |
3391 | ||
3392 | ||
3393 | static void | |
3394 | smtp_rset_handler(void) | |
3395 | { | |
3396 | HAD(SCH_RSET); | |
3397 | incomplete_transaction_log(US"RSET"); | |
3398 | smtp_printf("250 Reset OK\r\n"); | |
3399 | cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE; | |
3400 | } | |
3401 | ||
3402 | ||
3403 | ||
059ec3d9 PH |
3404 | /************************************************* |
3405 | * Initialize for SMTP incoming message * | |
3406 | *************************************************/ | |
3407 | ||
3408 | /* This function conducts the initial dialogue at the start of an incoming SMTP | |
3409 | message, and builds a list of recipients. However, if the incoming message | |
3410 | is part of a batch (-bS option) a separate function is called since it would | |
3411 | be messy having tests splattered about all over this function. This function | |
3412 | therefore handles the case where interaction is occurring. The input and output | |
3413 | files are set up in smtp_in and smtp_out. | |
3414 | ||
3415 | The global recipients_list is set to point to a vector of recipient_item | |
3416 | blocks, whose number is given by recipients_count. This is extended by the | |
3417 | receive_add_recipient() function. The global variable sender_address is set to | |
3418 | the sender's address. The yield is +1 if a message has been successfully | |
3419 | started, 0 if a QUIT command was encountered or the connection was refused from | |
3420 | the particular host, or -1 if the connection was lost. | |
3421 | ||
3422 | Argument: none | |
3423 | ||
3424 | Returns: > 0 message successfully started (reached DATA) | |
3425 | = 0 QUIT read or end of file reached or call refused | |
3426 | < 0 lost connection | |
3427 | */ | |
3428 | ||
3429 | int | |
3430 | smtp_setup_msg(void) | |
3431 | { | |
3432 | int done = 0; | |
3433 | BOOL toomany = FALSE; | |
3434 | BOOL discarded = FALSE; | |
3435 | BOOL last_was_rej_mail = FALSE; | |
3436 | BOOL last_was_rcpt = FALSE; | |
3437 | void *reset_point = store_get(0); | |
3438 | ||
3439 | DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n"); | |
3440 | ||
3441 | /* Reset for start of new message. We allow one RSET not to be counted as a | |
3442 | nonmail command, for those MTAs that insist on sending it between every | |
3443 | message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of | |
3444 | TLS between messages (an Exim client may do this if it has messages queued up | |
3445 | for the host). Note: we do NOT reset AUTH at this point. */ | |
3446 | ||
3447 | smtp_reset(reset_point); | |
3448 | message_ended = END_NOTSTARTED; | |
3449 | ||
7e3ce68e JH |
3450 | chunking_state = chunking_offered ? CHUNKING_OFFERED : CHUNKING_NOT_OFFERED; |
3451 | ||
059ec3d9 PH |
3452 | cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE; |
3453 | cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE; | |
3454 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
3455 | #ifdef SUPPORT_TLS | |
3456 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE; | |
b3ef41c9 | 3457 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; |
059ec3d9 PH |
3458 | #endif |
3459 | ||
3460 | /* Set the local signal handler for SIGTERM - it tries to end off tidily */ | |
3461 | ||
3462 | os_non_restarting_signal(SIGTERM, command_sigterm_handler); | |
3463 | ||
3464 | /* Batched SMTP is handled in a different function. */ | |
3465 | ||
3466 | if (smtp_batched_input) return smtp_setup_batch_msg(); | |
3467 | ||
3468 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
3469 | value. The values are 2 larger than the required yield of the function. */ | |
3470 | ||
3471 | while (done <= 0) | |
3472 | { | |
55414b25 | 3473 | const uschar **argv; |
059ec3d9 PH |
3474 | uschar *etrn_command; |
3475 | uschar *etrn_serialize_key; | |
3476 | uschar *errmess; | |
4e88a19f PH |
3477 | uschar *log_msg, *smtp_code; |
3478 | uschar *user_msg = NULL; | |
059ec3d9 PH |
3479 | uschar *recipient = NULL; |
3480 | uschar *hello = NULL; | |
059ec3d9 PH |
3481 | uschar *s, *ss; |
3482 | BOOL was_rej_mail = FALSE; | |
3483 | BOOL was_rcpt = FALSE; | |
3484 | void (*oldsignal)(int); | |
3485 | pid_t pid; | |
3486 | int start, end, sender_domain, recipient_domain; | |
3487 | int ptr, size, rc; | |
aa7751be | 3488 | int c; |
059ec3d9 | 3489 | auth_instance *au; |
6c1c3d1d WB |
3490 | uschar *orcpt = NULL; |
3491 | int flags; | |
059ec3d9 | 3492 | |
b3ef41c9 JH |
3493 | #if defined(SUPPORT_TLS) && defined(AUTH_TLS) |
3494 | /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */ | |
3495 | if ( tls_in.active >= 0 | |
3496 | && tls_in.peercert | |
3497 | && tls_in.certificate_verified | |
3498 | && cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd | |
3499 | ) | |
3500 | { | |
3501 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = FALSE; | |
4f6ae5c3 JH |
3502 | if ( acl_smtp_auth |
3503 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
3504 | &user_msg, &log_msg)) != OK | |
3505 | ) | |
b3ef41c9 | 3506 | { |
4f6ae5c3 JH |
3507 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); |
3508 | continue; | |
b3ef41c9 JH |
3509 | } |
3510 | ||
3511 | for (au = auths; au; au = au->next) | |
3512 | if (strcmpic(US"tls", au->driver_name) == 0) | |
3513 | { | |
3514 | smtp_cmd_data = NULL; | |
3515 | ||
805bb5c3 | 3516 | if (smtp_in_auth(au, &s, &ss) == OK) |
cb570b5e | 3517 | { DEBUG(D_auth) debug_printf("tls auth succeeded\n"); } |
805bb5c3 | 3518 | else |
cb570b5e | 3519 | { DEBUG(D_auth) debug_printf("tls auth not succeeded\n"); } |
b3ef41c9 JH |
3520 | break; |
3521 | } | |
3522 | } | |
3523 | #endif | |
3524 | ||
059ec3d9 PH |
3525 | switch(smtp_read_command(TRUE)) |
3526 | { | |
3527 | /* The AUTH command is not permitted to occur inside a transaction, and may | |
c46782ef PH |
3528 | occur successfully only once per connection. Actually, that isn't quite |
3529 | true. When TLS is started, all previous information about a connection must | |
3530 | be discarded, so a new AUTH is permitted at that time. | |
3531 | ||
3532 | AUTH may only be used when it has been advertised. However, it seems that | |
3533 | there are clients that send AUTH when it hasn't been advertised, some of | |
3534 | them even doing this after HELO. And there are MTAs that accept this. Sigh. | |
3535 | So there's a get-out that allows this to happen. | |
059ec3d9 PH |
3536 | |
3537 | AUTH is initially labelled as a "nonmail command" so that one occurrence | |
3538 | doesn't get counted. We change the label here so that multiple failing | |
3539 | AUTHS will eventually hit the nonmail threshold. */ | |
3540 | ||
3541 | case AUTH_CMD: | |
b4ed4da0 | 3542 | HAD(SCH_AUTH); |
059ec3d9 PH |
3543 | authentication_failed = TRUE; |
3544 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE; | |
3545 | ||
c46782ef | 3546 | if (!auth_advertised && !allow_auth_unadvertised) |
059ec3d9 PH |
3547 | { |
3548 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3549 | US"AUTH command used when not advertised"); | |
3550 | break; | |
3551 | } | |
b3ef41c9 | 3552 | if (sender_host_authenticated) |
059ec3d9 PH |
3553 | { |
3554 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3555 | US"already authenticated"); | |
3556 | break; | |
3557 | } | |
b3ef41c9 | 3558 | if (sender_address) |
059ec3d9 PH |
3559 | { |
3560 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
3561 | US"not permitted in mail transaction"); | |
3562 | break; | |
3563 | } | |
3564 | ||
3565 | /* Check the ACL */ | |
3566 | ||
4f6ae5c3 JH |
3567 | if ( acl_smtp_auth |
3568 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
3569 | &user_msg, &log_msg)) != OK | |
3570 | ) | |
059ec3d9 | 3571 | { |
4f6ae5c3 JH |
3572 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); |
3573 | break; | |
059ec3d9 PH |
3574 | } |
3575 | ||
3576 | /* Find the name of the requested authentication mechanism. */ | |
3577 | ||
ca86f471 PH |
3578 | s = smtp_cmd_data; |
3579 | while ((c = *smtp_cmd_data) != 0 && !isspace(c)) | |
059ec3d9 PH |
3580 | { |
3581 | if (!isalnum(c) && c != '-' && c != '_') | |
3582 | { | |
3583 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
3584 | US"invalid character in authentication mechanism name"); | |
3585 | goto COMMAND_LOOP; | |
3586 | } | |
ca86f471 | 3587 | smtp_cmd_data++; |
059ec3d9 PH |
3588 | } |
3589 | ||
3590 | /* If not at the end of the line, we must be at white space. Terminate the | |
3591 | name and move the pointer on to any data that may be present. */ | |
3592 | ||
ca86f471 | 3593 | if (*smtp_cmd_data != 0) |
059ec3d9 | 3594 | { |
ca86f471 PH |
3595 | *smtp_cmd_data++ = 0; |
3596 | while (isspace(*smtp_cmd_data)) smtp_cmd_data++; | |
059ec3d9 PH |
3597 | } |
3598 | ||
3599 | /* Search for an authentication mechanism which is configured for use | |
c46782ef PH |
3600 | as a server and which has been advertised (unless, sigh, allow_auth_ |
3601 | unadvertised is set). */ | |
059ec3d9 | 3602 | |
b3ef41c9 | 3603 | for (au = auths; au; au = au->next) |
059ec3d9 | 3604 | if (strcmpic(s, au->public_name) == 0 && au->server && |
b3ef41c9 JH |
3605 | (au->advertised || allow_auth_unadvertised)) |
3606 | break; | |
059ec3d9 | 3607 | |
b3ef41c9 | 3608 | if (au) |
059ec3d9 | 3609 | { |
b3ef41c9 | 3610 | c = smtp_in_auth(au, &s, &ss); |
059ec3d9 | 3611 | |
b3ef41c9 JH |
3612 | smtp_printf("%s\r\n", s); |
3613 | if (c != OK) | |
3614 | log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s", | |
3615 | au->name, host_and_ident(FALSE), ss); | |
059ec3d9 | 3616 | } |
b3ef41c9 JH |
3617 | else |
3618 | done = synprot_error(L_smtp_protocol_error, 504, NULL, | |
3619 | string_sprintf("%s authentication mechanism not supported", s)); | |
059ec3d9 PH |
3620 | |
3621 | break; /* AUTH_CMD */ | |
3622 | ||
3623 | /* The HELO/EHLO commands are permitted to appear in the middle of a | |
3624 | session as well as at the beginning. They have the effect of a reset in | |
3625 | addition to their other functions. Their absence at the start cannot be | |
3626 | taken to be an error. | |
3627 | ||
3628 | RFC 2821 says: | |
3629 | ||
3630 | If the EHLO command is not acceptable to the SMTP server, 501, 500, | |
3631 | or 502 failure replies MUST be returned as appropriate. The SMTP | |
3632 | server MUST stay in the same state after transmitting these replies | |
3633 | that it was in before the EHLO was received. | |
3634 | ||
3635 | Therefore, we do not do the reset until after checking the command for | |
3636 | acceptability. This change was made for Exim release 4.11. Previously | |
3637 | it did the reset first. */ | |
3638 | ||
3639 | case HELO_CMD: | |
b4ed4da0 | 3640 | HAD(SCH_HELO); |
059ec3d9 PH |
3641 | hello = US"HELO"; |
3642 | esmtp = FALSE; | |
3643 | goto HELO_EHLO; | |
3644 | ||
3645 | case EHLO_CMD: | |
b4ed4da0 | 3646 | HAD(SCH_EHLO); |
059ec3d9 PH |
3647 | hello = US"EHLO"; |
3648 | esmtp = TRUE; | |
3649 | ||
3650 | HELO_EHLO: /* Common code for HELO and EHLO */ | |
3651 | cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE; | |
3652 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE; | |
3653 | ||
3654 | /* Reject the HELO if its argument was invalid or non-existent. A | |
3655 | successful check causes the argument to be saved in malloc store. */ | |
3656 | ||
ca86f471 | 3657 | if (!check_helo(smtp_cmd_data)) |
059ec3d9 PH |
3658 | { |
3659 | smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello); | |
3660 | ||
3661 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically " | |
3662 | "invalid argument(s): %s", hello, host_and_ident(FALSE), | |
3ee512ff PH |
3663 | (*smtp_cmd_argument == 0)? US"(no argument given)" : |
3664 | string_printing(smtp_cmd_argument)); | |
059ec3d9 PH |
3665 | |
3666 | if (++synprot_error_count > smtp_max_synprot_errors) | |
3667 | { | |
3668 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
3669 | "syntax or protocol errors (last command was \"%s\")", | |
0ebc4d69 | 3670 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
3671 | done = 1; |
3672 | } | |
3673 | ||
3674 | break; | |
3675 | } | |
3676 | ||
3677 | /* If sender_host_unknown is true, we have got here via the -bs interface, | |
3678 | not called from inetd. Otherwise, we are running an IP connection and the | |
3679 | host address will be set. If the helo name is the primary name of this | |
3680 | host and we haven't done a reverse lookup, force one now. If helo_required | |
3681 | is set, ensure that the HELO name matches the actual host. If helo_verify | |
3682 | is set, do the same check, but softly. */ | |
3683 | ||
3684 | if (!sender_host_unknown) | |
3685 | { | |
3686 | BOOL old_helo_verified = helo_verified; | |
ca86f471 | 3687 | uschar *p = smtp_cmd_data; |
059ec3d9 PH |
3688 | |
3689 | while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; } | |
3690 | *p = 0; | |
3691 | ||
3692 | /* Force a reverse lookup if HELO quoted something in helo_lookup_domains | |
3693 | because otherwise the log can be confusing. */ | |
3694 | ||
3695 | if (sender_host_name == NULL && | |
3696 | (deliver_domain = sender_helo_name, /* set $domain */ | |
55414b25 | 3697 | match_isinlist(sender_helo_name, CUSS &helo_lookup_domains, 0, |
059ec3d9 PH |
3698 | &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL)) == OK) |
3699 | (void)host_name_lookup(); | |
3700 | ||
3701 | /* Rebuild the fullhost info to include the HELO name (and the real name | |
3702 | if it was looked up.) */ | |
3703 | ||
3704 | host_build_sender_fullhost(); /* Rebuild */ | |
3705 | set_process_info("handling%s incoming connection from %s", | |
817d9f57 | 3706 | (tls_in.active >= 0)? " TLS" : "", host_and_ident(FALSE)); |
059ec3d9 PH |
3707 | |
3708 | /* Verify if configured. This doesn't give much security, but it does | |
d7b47fd0 PH |
3709 | make some people happy to be able to do it. If helo_required is set, |
3710 | (host matches helo_verify_hosts) failure forces rejection. If helo_verify | |
3711 | is set (host matches helo_try_verify_hosts), it does not. This is perhaps | |
3712 | now obsolescent, since the verification can now be requested selectively | |
3713 | at ACL time. */ | |
059ec3d9 | 3714 | |
1705dd20 | 3715 | helo_verified = helo_verify_failed = sender_helo_dnssec = FALSE; |
059ec3d9 PH |
3716 | if (helo_required || helo_verify) |
3717 | { | |
d7b47fd0 | 3718 | BOOL tempfail = !smtp_verify_helo(); |
059ec3d9 PH |
3719 | if (!helo_verified) |
3720 | { | |
3721 | if (helo_required) | |
3722 | { | |
3723 | smtp_printf("%d %s argument does not match calling host\r\n", | |
3724 | tempfail? 451 : 550, hello); | |
3725 | log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s", | |
3726 | tempfail? "temporarily " : "", | |
3727 | hello, sender_helo_name, host_and_ident(FALSE)); | |
3728 | helo_verified = old_helo_verified; | |
3729 | break; /* End of HELO/EHLO processing */ | |
3730 | } | |
3731 | HDEBUG(D_all) debug_printf("%s verification failed but host is in " | |
3732 | "helo_try_verify_hosts\n", hello); | |
3733 | } | |
3734 | } | |
3735 | } | |
3736 | ||
8523533c TK |
3737 | #ifdef EXPERIMENTAL_SPF |
3738 | /* set up SPF context */ | |
3739 | spf_init(sender_helo_name, sender_host_address); | |
3740 | #endif | |
3741 | ||
a14e5636 PH |
3742 | /* Apply an ACL check if one is defined; afterwards, recheck |
3743 | synchronization in case the client started sending in a delay. */ | |
059ec3d9 | 3744 | |
4f6ae5c3 JH |
3745 | if (acl_smtp_helo) |
3746 | if ((rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, | |
3747 | &user_msg, &log_msg)) != OK) | |
059ec3d9 PH |
3748 | { |
3749 | done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg); | |
3750 | sender_helo_name = NULL; | |
3751 | host_build_sender_fullhost(); /* Rebuild */ | |
3752 | break; | |
3753 | } | |
a14e5636 | 3754 | else if (!check_sync()) goto SYNC_FAILURE; |
059ec3d9 | 3755 | |
4e88a19f PH |
3756 | /* Generate an OK reply. The default string includes the ident if present, |
3757 | and also the IP address if present. Reflecting back the ident is intended | |
3758 | as a deterrent to mail forgers. For maximum efficiency, and also because | |
3759 | some broken systems expect each response to be in a single packet, arrange | |
3760 | that the entire reply is sent in one write(). */ | |
059ec3d9 PH |
3761 | |
3762 | auth_advertised = FALSE; | |
3763 | pipelining_advertised = FALSE; | |
d1a13eea | 3764 | #ifdef SUPPORT_TLS |
059ec3d9 | 3765 | tls_advertised = FALSE; |
d1a13eea | 3766 | #endif |
6c1c3d1d | 3767 | dsn_advertised = FALSE; |
8c5d388a | 3768 | #ifdef SUPPORT_I18N |
d1a13eea JH |
3769 | smtputf8_advertised = FALSE; |
3770 | #endif | |
059ec3d9 | 3771 | |
d6a96edc | 3772 | smtp_code = US"250 "; /* Default response code plus space*/ |
4e88a19f PH |
3773 | if (user_msg == NULL) |
3774 | { | |
3775 | s = string_sprintf("%.3s %s Hello %s%s%s", | |
3776 | smtp_code, | |
3777 | smtp_active_hostname, | |
3778 | (sender_ident == NULL)? US"" : sender_ident, | |
3779 | (sender_ident == NULL)? US"" : US" at ", | |
3780 | (sender_host_name == NULL)? sender_helo_name : sender_host_name); | |
3781 | ||
3782 | ptr = Ustrlen(s); | |
3783 | size = ptr + 1; | |
059ec3d9 | 3784 | |
4e88a19f PH |
3785 | if (sender_host_address != NULL) |
3786 | { | |
c2f669a4 JH |
3787 | s = string_catn(s, &size, &ptr, US" [", 2); |
3788 | s = string_cat (s, &size, &ptr, sender_host_address); | |
3789 | s = string_catn(s, &size, &ptr, US"]", 1); | |
4e88a19f PH |
3790 | } |
3791 | } | |
3792 | ||
d6a96edc PH |
3793 | /* A user-supplied EHLO greeting may not contain more than one line. Note |
3794 | that the code returned by smtp_message_code() includes the terminating | |
3795 | whitespace character. */ | |
059ec3d9 | 3796 | |
4e88a19f | 3797 | else |
059ec3d9 | 3798 | { |
4e88a19f | 3799 | char *ss; |
d6a96edc | 3800 | int codelen = 4; |
4f6ae5c3 | 3801 | smtp_message_code(&smtp_code, &codelen, &user_msg, NULL, TRUE); |
d6a96edc | 3802 | s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg); |
4e88a19f PH |
3803 | if ((ss = strpbrk(CS s, "\r\n")) != NULL) |
3804 | { | |
3805 | log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain " | |
3806 | "newlines: message truncated: %s", string_printing(s)); | |
3807 | *ss = 0; | |
3808 | } | |
3809 | ptr = Ustrlen(s); | |
3810 | size = ptr + 1; | |
059ec3d9 PH |
3811 | } |
3812 | ||
c2f669a4 | 3813 | s = string_catn(s, &size, &ptr, US"\r\n", 2); |
059ec3d9 PH |
3814 | |
3815 | /* If we received EHLO, we must create a multiline response which includes | |
3816 | the functions supported. */ | |
3817 | ||
3818 | if (esmtp) | |
3819 | { | |
3820 | s[3] = '-'; | |
3821 | ||
3822 | /* I'm not entirely happy with this, as an MTA is supposed to check | |
3823 | that it has enough room to accept a message of maximum size before | |
3824 | it sends this. However, there seems little point in not sending it. | |
3825 | The actual size check happens later at MAIL FROM time. By postponing it | |
3826 | till then, VRFY and EXPN can be used after EHLO when space is short. */ | |
3827 | ||
3828 | if (thismessage_size_limit > 0) | |
3829 | { | |
4e88a19f PH |
3830 | sprintf(CS big_buffer, "%.3s-SIZE %d\r\n", smtp_code, |
3831 | thismessage_size_limit); | |
c2f669a4 | 3832 | s = string_cat(s, &size, &ptr, big_buffer); |
059ec3d9 PH |
3833 | } |
3834 | else | |
3835 | { | |
c2f669a4 JH |
3836 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3837 | s = string_catn(s, &size, &ptr, US"-SIZE\r\n", 7); | |
059ec3d9 PH |
3838 | } |
3839 | ||
3840 | /* Exim does not do protocol conversion or data conversion. It is 8-bit | |
3841 | clean; if it has an 8-bit character in its hand, it just sends it. It | |
3842 | cannot therefore specify 8BITMIME and remain consistent with the RFCs. | |
3843 | However, some users want this option simply in order to stop MUAs | |
3844 | mangling messages that contain top-bit-set characters. It is therefore | |
3845 | provided as an option. */ | |
3846 | ||
3847 | if (accept_8bitmime) | |
4e88a19f | 3848 | { |
c2f669a4 JH |
3849 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3850 | s = string_catn(s, &size, &ptr, US"-8BITMIME\r\n", 11); | |
4e88a19f | 3851 | } |
059ec3d9 | 3852 | |
6c1c3d1d | 3853 | /* Advertise DSN support if configured to do so. */ |
94431adb | 3854 | if (verify_check_host(&dsn_advertise_hosts) != FAIL) |
6c1c3d1d | 3855 | { |
c2f669a4 JH |
3856 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3857 | s = string_catn(s, &size, &ptr, US"-DSN\r\n", 6); | |
6c1c3d1d WB |
3858 | dsn_advertised = TRUE; |
3859 | } | |
6c1c3d1d | 3860 | |
059ec3d9 PH |
3861 | /* Advertise ETRN if there's an ACL checking whether a host is |
3862 | permitted to issue it; a check is made when any host actually tries. */ | |
3863 | ||
3864 | if (acl_smtp_etrn != NULL) | |
3865 | { | |
c2f669a4 JH |
3866 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3867 | s = string_catn(s, &size, &ptr, US"-ETRN\r\n", 7); | |
059ec3d9 PH |
3868 | } |
3869 | ||
3870 | /* Advertise EXPN if there's an ACL checking whether a host is | |
3871 | permitted to issue it; a check is made when any host actually tries. */ | |
3872 | ||
3873 | if (acl_smtp_expn != NULL) | |
3874 | { | |
c2f669a4 JH |
3875 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3876 | s = string_catn(s, &size, &ptr, US"-EXPN\r\n", 7); | |
059ec3d9 PH |
3877 | } |
3878 | ||
3879 | /* Exim is quite happy with pipelining, so let the other end know that | |
3880 | it is safe to use it, unless advertising is disabled. */ | |
3881 | ||
cf8b11a5 PH |
3882 | if (pipelining_enable && |
3883 | verify_check_host(&pipelining_advertise_hosts) == OK) | |
059ec3d9 | 3884 | { |
c2f669a4 JH |
3885 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3886 | s = string_catn(s, &size, &ptr, US"-PIPELINING\r\n", 13); | |
059ec3d9 PH |
3887 | sync_cmd_limit = NON_SYNC_CMD_PIPELINING; |
3888 | pipelining_advertised = TRUE; | |
3889 | } | |
3890 | ||
fd98a5c6 | 3891 | |
059ec3d9 PH |
3892 | /* If any server authentication mechanisms are configured, advertise |
3893 | them if the current host is in auth_advertise_hosts. The problem with | |
3894 | advertising always is that some clients then require users to | |
3895 | authenticate (and aren't configurable otherwise) even though it may not | |
3896 | be necessary (e.g. if the host is in host_accept_relay). | |
3897 | ||
3898 | RFC 2222 states that SASL mechanism names contain only upper case | |
3899 | letters, so output the names in upper case, though we actually recognize | |
3900 | them in either case in the AUTH command. */ | |
3901 | ||
b3ef41c9 JH |
3902 | if ( auths |
3903 | #if defined(SUPPORT_TLS) && defined(AUTH_TLS) | |
3904 | && !sender_host_authenticated | |
3905 | #endif | |
3906 | && verify_check_host(&auth_advertise_hosts) == OK | |
3907 | ) | |
3908 | { | |
3909 | auth_instance *au; | |
3910 | BOOL first = TRUE; | |
3911 | for (au = auths; au; au = au->next) | |
3912 | if (au->server && (au->advertise_condition == NULL || | |
3913 | expand_check_condition(au->advertise_condition, au->name, | |
3914 | US"authenticator"))) | |
3915 | { | |
3916 | int saveptr; | |
3917 | if (first) | |
3918 | { | |
c2f669a4 JH |
3919 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3920 | s = string_catn(s, &size, &ptr, US"-AUTH", 5); | |
b3ef41c9 JH |
3921 | first = FALSE; |
3922 | auth_advertised = TRUE; | |
3923 | } | |
3924 | saveptr = ptr; | |
c2f669a4 JH |
3925 | s = string_catn(s, &size, &ptr, US" ", 1); |
3926 | s = string_cat (s, &size, &ptr, au->public_name); | |
b3ef41c9 JH |
3927 | while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]); |
3928 | au->advertised = TRUE; | |
3929 | } | |
3930 | else | |
3931 | au->advertised = FALSE; | |
3932 | ||
c2f669a4 | 3933 | if (!first) s = string_catn(s, &size, &ptr, US"\r\n", 2); |
b3ef41c9 | 3934 | } |
059ec3d9 | 3935 | |
18481de3 | 3936 | /* RFC 3030 CHUNKING */ |
059ec3d9 | 3937 | |
aa368db3 JH |
3938 | if (verify_check_host(&chunking_advertise_hosts) != FAIL) |
3939 | { | |
3940 | s = string_catn(s, &size, &ptr, smtp_code, 3); | |
3941 | s = string_catn(s, &size, &ptr, US"-CHUNKING\r\n", 11); | |
7e3ce68e | 3942 | chunking_offered = TRUE; |
18481de3 | 3943 | chunking_state = CHUNKING_OFFERED; |
aa368db3 JH |
3944 | } |
3945 | ||
18481de3 JH |
3946 | /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer) |
3947 | if it has been included in the binary, and the host matches | |
3948 | tls_advertise_hosts. We must *not* advertise if we are already in a | |
3949 | secure connection. */ | |
3950 | ||
d1a13eea | 3951 | #ifdef SUPPORT_TLS |
817d9f57 | 3952 | if (tls_in.active < 0 && |
059ec3d9 PH |
3953 | verify_check_host(&tls_advertise_hosts) != FAIL) |
3954 | { | |
c2f669a4 JH |
3955 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3956 | s = string_catn(s, &size, &ptr, US"-STARTTLS\r\n", 11); | |
059ec3d9 PH |
3957 | tls_advertised = TRUE; |
3958 | } | |
d1a13eea | 3959 | #endif |
059ec3d9 | 3960 | |
d1a13eea | 3961 | #ifndef DISABLE_PRDR |
fd98a5c6 | 3962 | /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */ |
8ccd00b1 JH |
3963 | if (prdr_enable) |
3964 | { | |
c2f669a4 JH |
3965 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3966 | s = string_catn(s, &size, &ptr, US"-PRDR\r\n", 7); | |
8ccd00b1 | 3967 | } |
d1a13eea JH |
3968 | #endif |
3969 | ||
8c5d388a | 3970 | #ifdef SUPPORT_I18N |
d1a13eea JH |
3971 | if ( accept_8bitmime |
3972 | && verify_check_host(&smtputf8_advertise_hosts) != FAIL) | |
3973 | { | |
c2f669a4 JH |
3974 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3975 | s = string_catn(s, &size, &ptr, US"-SMTPUTF8\r\n", 11); | |
d1a13eea JH |
3976 | smtputf8_advertised = TRUE; |
3977 | } | |
3978 | #endif | |
fd98a5c6 | 3979 | |
059ec3d9 PH |
3980 | /* Finish off the multiline reply with one that is always available. */ |
3981 | ||
c2f669a4 JH |
3982 | s = string_catn(s, &size, &ptr, smtp_code, 3); |
3983 | s = string_catn(s, &size, &ptr, US" HELP\r\n", 7); | |
059ec3d9 PH |
3984 | } |
3985 | ||
3986 | /* Terminate the string (for debug), write it, and note that HELO/EHLO | |
3987 | has been seen. */ | |
3988 | ||
3989 | s[ptr] = 0; | |
3990 | ||
d1a13eea | 3991 | #ifdef SUPPORT_TLS |
817d9f57 | 3992 | if (tls_in.active >= 0) (void)tls_write(TRUE, s, ptr); else |
d1a13eea | 3993 | #endif |
059ec3d9 | 3994 | |
1ac6b2e7 JH |
3995 | { |
3996 | int i = fwrite(s, 1, ptr, smtp_out); i = i; /* compiler quietening */ | |
3997 | } | |
898d150f PH |
3998 | DEBUG(D_receive) |
3999 | { | |
4000 | uschar *cr; | |
4001 | while ((cr = Ustrchr(s, '\r')) != NULL) /* lose CRs */ | |
4002 | memmove(cr, cr + 1, (ptr--) - (cr - s)); | |
4003 | debug_printf("SMTP>> %s", s); | |
4004 | } | |
059ec3d9 | 4005 | helo_seen = TRUE; |
4e88a19f PH |
4006 | |
4007 | /* Reset the protocol and the state, abandoning any previous message. */ | |
e524074d JH |
4008 | received_protocol = |
4009 | (sender_host_address ? protocols : protocols_local) | |
4010 | [ (esmtp | |
4011 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
4012 | : pnormal) | |
4013 | + (tls_in.active >= 0 ? pcrpted : 0) | |
4014 | ]; | |
4e88a19f PH |
4015 | smtp_reset(reset_point); |
4016 | toomany = FALSE; | |
059ec3d9 PH |
4017 | break; /* HELO/EHLO */ |
4018 | ||
4019 | ||
4020 | /* The MAIL command requires an address as an operand. All we do | |
4021 | here is to parse it for syntactic correctness. The form "<>" is | |
4022 | a special case which converts into an empty string. The start/end | |
4023 | pointers in the original are not used further for this address, as | |
4024 | it is the canonical extracted address which is all that is kept. */ | |
4025 | ||
4026 | case MAIL_CMD: | |
b4ed4da0 | 4027 | HAD(SCH_MAIL); |
059ec3d9 PH |
4028 | smtp_mailcmd_count++; /* Count for limit and ratelimit */ |
4029 | was_rej_mail = TRUE; /* Reset if accepted */ | |
d27f98fe | 4030 | env_mail_type_t * mail_args; /* Sanity check & validate args */ |
059ec3d9 PH |
4031 | |
4032 | if (helo_required && !helo_seen) | |
4033 | { | |
4034 | smtp_printf("503 HELO or EHLO required\r\n"); | |
4035 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no " | |
4036 | "HELO/EHLO given", host_and_ident(FALSE)); | |
4037 | break; | |
4038 | } | |
4039 | ||
4040 | if (sender_address != NULL) | |
4041 | { | |
4042 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4043 | US"sender already given"); | |
4044 | break; | |
4045 | } | |
4046 | ||
ca86f471 | 4047 | if (smtp_cmd_data[0] == 0) |
059ec3d9 PH |
4048 | { |
4049 | done = synprot_error(L_smtp_protocol_error, 501, NULL, | |
4050 | US"MAIL must have an address operand"); | |
4051 | break; | |
4052 | } | |
4053 | ||
4054 | /* Check to see if the limit for messages per connection would be | |
4055 | exceeded by accepting further messages. */ | |
4056 | ||
4057 | if (smtp_accept_max_per_connection > 0 && | |
4058 | smtp_mailcmd_count > smtp_accept_max_per_connection) | |
4059 | { | |
4060 | smtp_printf("421 too many messages in this connection\r\n"); | |
4061 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many " | |
4062 | "messages in one connection", host_and_ident(TRUE)); | |
4063 | break; | |
4064 | } | |
4065 | ||
4066 | /* Reset for start of message - even if this is going to fail, we | |
4067 | obviously need to throw away any previous data. */ | |
4068 | ||
4069 | smtp_reset(reset_point); | |
4070 | toomany = FALSE; | |
4071 | sender_data = recipient_data = NULL; | |
4072 | ||
4073 | /* Loop, checking for ESMTP additions to the MAIL FROM command. */ | |
4074 | ||
4075 | if (esmtp) for(;;) | |
4076 | { | |
4077 | uschar *name, *value, *end; | |
4078 | unsigned long int size; | |
d27f98fe | 4079 | BOOL arg_error = FALSE; |
059ec3d9 PH |
4080 | |
4081 | if (!extract_option(&name, &value)) break; | |
4082 | ||
d27f98fe | 4083 | for (mail_args = env_mail_type_list; |
2ef7ed08 | 4084 | mail_args->value != ENV_MAIL_OPT_NULL; |
d27f98fe TL |
4085 | mail_args++ |
4086 | ) | |
d27f98fe TL |
4087 | if (strcmpic(name, mail_args->name) == 0) |
4088 | break; | |
d27f98fe TL |
4089 | if (mail_args->need_value && strcmpic(value, US"") == 0) |
4090 | break; | |
059ec3d9 | 4091 | |
d27f98fe | 4092 | switch(mail_args->value) |
059ec3d9 | 4093 | { |
d27f98fe TL |
4094 | /* Handle SIZE= by reading the value. We don't do the check till later, |
4095 | in order to be able to log the sender address on failure. */ | |
4096 | case ENV_MAIL_OPT_SIZE: | |
d27f98fe | 4097 | if (((size = Ustrtoul(value, &end, 10)), *end == 0)) |
059ec3d9 | 4098 | { |
d27f98fe TL |
4099 | if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX) |
4100 | size = INT_MAX; | |
4101 | message_size = (int)size; | |
059ec3d9 PH |
4102 | } |
4103 | else | |
d27f98fe TL |
4104 | arg_error = TRUE; |
4105 | break; | |
059ec3d9 | 4106 | |
d27f98fe TL |
4107 | /* If this session was initiated with EHLO and accept_8bitmime is set, |
4108 | Exim will have indicated that it supports the BODY=8BITMIME option. In | |
4109 | fact, it does not support this according to the RFCs, in that it does not | |
4110 | take any special action for forwarding messages containing 8-bit | |
4111 | characters. That is why accept_8bitmime is not the default setting, but | |
4112 | some sites want the action that is provided. We recognize both "8BITMIME" | |
4113 | and "7BIT" as body types, but take no action. */ | |
4114 | case ENV_MAIL_OPT_BODY: | |
3c0a92dc | 4115 | if (accept_8bitmime) { |
9d4319df | 4116 | if (strcmpic(value, US"8BITMIME") == 0) |
3c0a92dc | 4117 | body_8bitmime = 8; |
9d4319df | 4118 | else if (strcmpic(value, US"7BIT") == 0) |
3c0a92dc | 4119 | body_8bitmime = 7; |
9d4319df JH |
4120 | else |
4121 | { | |
3c0a92dc JH |
4122 | body_8bitmime = 0; |
4123 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4124 | US"invalid data for BODY"); | |
4125 | goto COMMAND_LOOP; | |
9d4319df | 4126 | } |
3c0a92dc JH |
4127 | DEBUG(D_receive) debug_printf("8BITMIME: %d\n", body_8bitmime); |
4128 | break; | |
4129 | } | |
d27f98fe TL |
4130 | arg_error = TRUE; |
4131 | break; | |
059ec3d9 | 4132 | |
6c1c3d1d WB |
4133 | /* Handle the two DSN options, but only if configured to do so (which |
4134 | will have caused "DSN" to be given in the EHLO response). The code itself | |
4135 | is included only if configured in at build time. */ | |
4136 | ||
4137 | case ENV_MAIL_OPT_RET: | |
9d4319df JH |
4138 | if (dsn_advertised) |
4139 | { | |
6c1c3d1d | 4140 | /* Check if RET has already been set */ |
9d4319df JH |
4141 | if (dsn_ret > 0) |
4142 | { | |
6c1c3d1d WB |
4143 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4144 | US"RET can be specified once only"); | |
4145 | goto COMMAND_LOOP; | |
9d4319df JH |
4146 | } |
4147 | dsn_ret = strcmpic(value, US"HDRS") == 0 | |
4148 | ? dsn_ret_hdrs | |
4149 | : strcmpic(value, US"FULL") == 0 | |
4150 | ? dsn_ret_full | |
4151 | : 0; | |
6c1c3d1d WB |
4152 | DEBUG(D_receive) debug_printf("DSN_RET: %d\n", dsn_ret); |
4153 | /* Check for invalid invalid value, and exit with error */ | |
9d4319df JH |
4154 | if (dsn_ret == 0) |
4155 | { | |
6c1c3d1d WB |
4156 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4157 | US"Value for RET is invalid"); | |
4158 | goto COMMAND_LOOP; | |
9d4319df JH |
4159 | } |
4160 | } | |
6c1c3d1d WB |
4161 | break; |
4162 | case ENV_MAIL_OPT_ENVID: | |
9d4319df JH |
4163 | if (dsn_advertised) |
4164 | { | |
6c1c3d1d | 4165 | /* Check if the dsn envid has been already set */ |
9d4319df JH |
4166 | if (dsn_envid != NULL) |
4167 | { | |
6c1c3d1d WB |
4168 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4169 | US"ENVID can be specified once only"); | |
4170 | goto COMMAND_LOOP; | |
9d4319df | 4171 | } |
6c1c3d1d WB |
4172 | dsn_envid = string_copy(value); |
4173 | DEBUG(D_receive) debug_printf("DSN_ENVID: %s\n", dsn_envid); | |
9d4319df | 4174 | } |
6c1c3d1d | 4175 | break; |
6c1c3d1d | 4176 | |
d27f98fe TL |
4177 | /* Handle the AUTH extension. If the value given is not "<>" and either |
4178 | the ACL says "yes" or there is no ACL but the sending host is | |
4179 | authenticated, we set it up as the authenticated sender. However, if the | |
4180 | authenticator set a condition to be tested, we ignore AUTH on MAIL unless | |
4181 | the condition is met. The value of AUTH is an xtext, which means that +, | |
4182 | = and cntrl chars are coded in hex; however "<>" is unaffected by this | |
4183 | coding. */ | |
4184 | case ENV_MAIL_OPT_AUTH: | |
4185 | if (Ustrcmp(value, "<>") != 0) | |
4186 | { | |
4187 | int rc; | |
4188 | uschar *ignore_msg; | |
059ec3d9 | 4189 | |
d27f98fe TL |
4190 | if (auth_xtextdecode(value, &authenticated_sender) < 0) |
4191 | { | |
4192 | /* Put back terminator overrides for error message */ | |
d27f98fe | 4193 | value[-1] = '='; |
fd98a5c6 | 4194 | name[-1] = ' '; |
d27f98fe TL |
4195 | done = synprot_error(L_smtp_syntax_error, 501, NULL, |
4196 | US"invalid data for AUTH"); | |
4197 | goto COMMAND_LOOP; | |
4198 | } | |
4199 | if (acl_smtp_mailauth == NULL) | |
4200 | { | |
4201 | ignore_msg = US"client not authenticated"; | |
4202 | rc = (sender_host_authenticated != NULL)? OK : FAIL; | |
4203 | } | |
4204 | else | |
4205 | { | |
4206 | ignore_msg = US"rejected by ACL"; | |
4207 | rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth, | |
4208 | &user_msg, &log_msg); | |
4209 | } | |
94431adb | 4210 | |
d27f98fe TL |
4211 | switch (rc) |
4212 | { | |
4213 | case OK: | |
9d4319df JH |
4214 | if (authenticated_by == NULL || |
4215 | authenticated_by->mail_auth_condition == NULL || | |
4216 | expand_check_condition(authenticated_by->mail_auth_condition, | |
4217 | authenticated_by->name, US"authenticator")) | |
4218 | break; /* Accept the AUTH */ | |
94431adb | 4219 | |
9d4319df JH |
4220 | ignore_msg = US"server_mail_auth_condition failed"; |
4221 | if (authenticated_id != NULL) | |
4222 | ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"", | |
4223 | ignore_msg, authenticated_id); | |
94431adb | 4224 | |
d27f98fe | 4225 | /* Fall through */ |
94431adb | 4226 | |
d27f98fe | 4227 | case FAIL: |
9d4319df JH |
4228 | authenticated_sender = NULL; |
4229 | log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)", | |
4230 | value, host_and_ident(TRUE), ignore_msg); | |
4231 | break; | |
94431adb | 4232 | |
d27f98fe TL |
4233 | /* Should only get DEFER or ERROR here. Put back terminator |
4234 | overrides for error message */ | |
94431adb | 4235 | |
d27f98fe | 4236 | default: |
9d4319df JH |
4237 | value[-1] = '='; |
4238 | name[-1] = ' '; | |
4239 | (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg, | |
4240 | log_msg); | |
4241 | goto COMMAND_LOOP; | |
d27f98fe | 4242 | } |
059ec3d9 | 4243 | } |
d27f98fe | 4244 | break; |
fd98a5c6 | 4245 | |
8ccd00b1 | 4246 | #ifndef DISABLE_PRDR |
fd98a5c6 | 4247 | case ENV_MAIL_OPT_PRDR: |
8ccd00b1 | 4248 | if (prdr_enable) |
fd98a5c6 JH |
4249 | prdr_requested = TRUE; |
4250 | break; | |
4251 | #endif | |
4252 | ||
8c5d388a | 4253 | #ifdef SUPPORT_I18N |
d1a13eea JH |
4254 | case ENV_MAIL_OPT_UTF8: |
4255 | if (smtputf8_advertised) | |
e524074d JH |
4256 | { |
4257 | DEBUG(D_receive) debug_printf("smtputf8 requested\n"); | |
9d4319df | 4258 | message_smtputf8 = allow_utf8_domains = TRUE; |
5a886ce7 | 4259 | received_protocol = string_sprintf("utf8%s", received_protocol); |
e524074d | 4260 | } |
d1a13eea JH |
4261 | break; |
4262 | #endif | |
2ef7ed08 | 4263 | /* No valid option. Stick back the terminator characters and break |
fd98a5c6 | 4264 | the loop. Do the name-terminator second as extract_option sets |
2ef7ed08 HSHR |
4265 | value==name when it found no equal-sign. |
4266 | An error for a malformed address will occur. */ | |
4267 | case ENV_MAIL_OPT_NULL: | |
d27f98fe | 4268 | value[-1] = '='; |
fd98a5c6 JH |
4269 | name[-1] = ' '; |
4270 | arg_error = TRUE; | |
d27f98fe | 4271 | break; |
2ef7ed08 HSHR |
4272 | |
4273 | default: assert(0); | |
059ec3d9 | 4274 | } |
d27f98fe TL |
4275 | /* Break out of for loop if switch() had bad argument or |
4276 | when start of the email address is reached */ | |
4277 | if (arg_error) break; | |
059ec3d9 PH |
4278 | } |
4279 | ||
4280 | /* If we have passed the threshold for rate limiting, apply the current | |
4281 | delay, and update it for next time, provided this is a limited host. */ | |
4282 | ||
4283 | if (smtp_mailcmd_count > smtp_rlm_threshold && | |
4284 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
4285 | { | |
4286 | DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n", | |
4287 | smtp_delay_mail/1000.0); | |
4288 | millisleep((int)smtp_delay_mail); | |
4289 | smtp_delay_mail *= smtp_rlm_factor; | |
4290 | if (smtp_delay_mail > (double)smtp_rlm_limit) | |
4291 | smtp_delay_mail = (double)smtp_rlm_limit; | |
4292 | } | |
4293 | ||
4294 | /* Now extract the address, first applying any SMTP-time rewriting. The | |
4295 | TRUE flag allows "<>" as a sender address. */ | |
4296 | ||
9d4319df JH |
4297 | raw_sender = rewrite_existflags & rewrite_smtp |
4298 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
4299 | global_rewrite_rules) | |
4300 | : smtp_cmd_data; | |
059ec3d9 | 4301 | |
059ec3d9 PH |
4302 | raw_sender = |
4303 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
4304 | TRUE); | |
059ec3d9 | 4305 | |
2685d6e0 | 4306 | if (!raw_sender) |
059ec3d9 | 4307 | { |
ca86f471 | 4308 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); |
059ec3d9 PH |
4309 | break; |
4310 | } | |
4311 | ||
4312 | sender_address = raw_sender; | |
4313 | ||
4314 | /* If there is a configured size limit for mail, check that this message | |
4315 | doesn't exceed it. The check is postponed to this point so that the sender | |
4316 | can be logged. */ | |
4317 | ||
4318 | if (thismessage_size_limit > 0 && message_size > thismessage_size_limit) | |
4319 | { | |
4320 | smtp_printf("552 Message size exceeds maximum permitted\r\n"); | |
4321 | log_write(L_size_reject, | |
4322 | LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: " | |
4323 | "message too big: size%s=%d max=%d", | |
4324 | sender_address, | |
4325 | host_and_ident(TRUE), | |
4326 | (message_size == INT_MAX)? ">" : "", | |
4327 | message_size, | |
4328 | thismessage_size_limit); | |
4329 | sender_address = NULL; | |
4330 | break; | |
4331 | } | |
4332 | ||
4333 | /* Check there is enough space on the disk unless configured not to. | |
4334 | When smtp_check_spool_space is set, the check is for thismessage_size_limit | |
4335 | plus the current message - i.e. we accept the message only if it won't | |
4336 | reduce the space below the threshold. Add 5000 to the size to allow for | |
4337 | overheads such as the Received: line and storing of recipients, etc. | |
4338 | By putting the check here, even when SIZE is not given, it allow VRFY | |
4339 | and EXPN etc. to be used when space is short. */ | |
4340 | ||
4341 | if (!receive_check_fs( | |
4342 | (smtp_check_spool_space && message_size >= 0)? | |
4343 | message_size + 5000 : 0)) | |
4344 | { | |
4345 | smtp_printf("452 Space shortage, please try later\r\n"); | |
4346 | sender_address = NULL; | |
4347 | break; | |
4348 | } | |
4349 | ||
4350 | /* If sender_address is unqualified, reject it, unless this is a locally | |
4351 | generated message, or the sending host or net is permitted to send | |
4352 | unqualified addresses - typically local machines behaving as MUAs - | |
4353 | in which case just qualify the address. The flag is set above at the start | |
4354 | of the SMTP connection. */ | |
4355 | ||
4356 | if (sender_domain == 0 && sender_address[0] != 0) | |
4357 | { | |
4358 | if (allow_unqualified_sender) | |
4359 | { | |
4360 | sender_domain = Ustrlen(sender_address) + 1; | |
4361 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
4362 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
4363 | raw_sender); | |
4364 | } | |
4365 | else | |
4366 | { | |
4367 | smtp_printf("501 %s: sender address must contain a domain\r\n", | |
ca86f471 | 4368 | smtp_cmd_data); |
059ec3d9 PH |
4369 | log_write(L_smtp_syntax_error, |
4370 | LOG_MAIN|LOG_REJECT, | |
4371 | "unqualified sender rejected: <%s> %s%s", | |
4372 | raw_sender, | |
4373 | host_and_ident(TRUE), | |
4374 | host_lookup_msg); | |
4375 | sender_address = NULL; | |
4376 | break; | |
4377 | } | |
4378 | } | |
4379 | ||
a14e5636 PH |
4380 | /* Apply an ACL check if one is defined, before responding. Afterwards, |
4381 | when pipelining is not advertised, do another sync check in case the ACL | |
4382 | delayed and the client started sending in the meantime. */ | |
059ec3d9 | 4383 | |
8ccd00b1 | 4384 | if (acl_smtp_mail) |
a14e5636 PH |
4385 | { |
4386 | rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg); | |
4387 | if (rc == OK && !pipelining_advertised && !check_sync()) | |
4388 | goto SYNC_FAILURE; | |
4389 | } | |
8ccd00b1 JH |
4390 | else |
4391 | rc = OK; | |
059ec3d9 PH |
4392 | |
4393 | if (rc == OK || rc == DISCARD) | |
4394 | { | |
8ccd00b1 | 4395 | if (!user_msg) |
fd98a5c6 | 4396 | smtp_printf("%s%s%s", US"250 OK", |
8ccd00b1 JH |
4397 | #ifndef DISABLE_PRDR |
4398 | prdr_requested ? US", PRDR Requested" : US"", | |
4399 | #else | |
fd98a5c6 | 4400 | US"", |
8ccd00b1 | 4401 | #endif |
fd98a5c6 | 4402 | US"\r\n"); |
94431adb | 4403 | else |
fd98a5c6 | 4404 | { |
8ccd00b1 JH |
4405 | #ifndef DISABLE_PRDR |
4406 | if (prdr_requested) | |
fd98a5c6 JH |
4407 | user_msg = string_sprintf("%s%s", user_msg, US", PRDR Requested"); |
4408 | #endif | |
8ccd00b1 | 4409 | smtp_user_msg(US"250", user_msg); |
fd98a5c6 | 4410 | } |
059ec3d9 PH |
4411 | smtp_delay_rcpt = smtp_rlr_base; |
4412 | recipients_discarded = (rc == DISCARD); | |
4413 | was_rej_mail = FALSE; | |
4414 | } | |
059ec3d9 PH |
4415 | else |
4416 | { | |
4417 | done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg); | |
4418 | sender_address = NULL; | |
4419 | } | |
4420 | break; | |
4421 | ||
4422 | ||
2679d413 PH |
4423 | /* The RCPT command requires an address as an operand. There may be any |
4424 | number of RCPT commands, specifying multiple recipients. We build them all | |
4425 | into a data structure. The start/end values given by parse_extract_address | |
4426 | are not used, as we keep only the extracted address. */ | |
059ec3d9 PH |
4427 | |
4428 | case RCPT_CMD: | |
b4ed4da0 | 4429 | HAD(SCH_RCPT); |
059ec3d9 | 4430 | rcpt_count++; |
2679d413 | 4431 | was_rcpt = rcpt_in_progress = TRUE; |
059ec3d9 PH |
4432 | |
4433 | /* There must be a sender address; if the sender was rejected and | |
4434 | pipelining was advertised, we assume the client was pipelining, and do not | |
4435 | count this as a protocol error. Reset was_rej_mail so that further RCPTs | |
4436 | get the same treatment. */ | |
4437 | ||
4438 | if (sender_address == NULL) | |
4439 | { | |
4440 | if (pipelining_advertised && last_was_rej_mail) | |
4441 | { | |
4442 | smtp_printf("503 sender not yet given\r\n"); | |
4443 | was_rej_mail = TRUE; | |
4444 | } | |
4445 | else | |
4446 | { | |
4447 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4448 | US"sender not yet given"); | |
4449 | was_rcpt = FALSE; /* Not a valid RCPT */ | |
4450 | } | |
4451 | rcpt_fail_count++; | |
4452 | break; | |
4453 | } | |
4454 | ||
4455 | /* Check for an operand */ | |
4456 | ||
ca86f471 | 4457 | if (smtp_cmd_data[0] == 0) |
059ec3d9 PH |
4458 | { |
4459 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4460 | US"RCPT must have an address operand"); | |
4461 | rcpt_fail_count++; | |
4462 | break; | |
4463 | } | |
50dc7409 | 4464 | |
6c1c3d1d WB |
4465 | /* Set the DSN flags orcpt and dsn_flags from the session*/ |
4466 | orcpt = NULL; | |
4467 | flags = 0; | |
4468 | ||
4469 | if (esmtp) for(;;) | |
4470 | { | |
45500060 | 4471 | uschar *name, *value; |
6c1c3d1d WB |
4472 | |
4473 | if (!extract_option(&name, &value)) | |
6c1c3d1d | 4474 | break; |
6c1c3d1d WB |
4475 | |
4476 | if (dsn_advertised && strcmpic(name, US"ORCPT") == 0) | |
4477 | { | |
4478 | /* Check whether orcpt has been already set */ | |
45500060 JH |
4479 | if (orcpt) |
4480 | { | |
6c1c3d1d WB |
4481 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4482 | US"ORCPT can be specified once only"); | |
4483 | goto COMMAND_LOOP; | |
4484 | } | |
4485 | orcpt = string_copy(value); | |
4486 | DEBUG(D_receive) debug_printf("DSN orcpt: %s\n", orcpt); | |
4487 | } | |
4488 | ||
4489 | else if (dsn_advertised && strcmpic(name, US"NOTIFY") == 0) | |
4490 | { | |
4491 | /* Check if the notify flags have been already set */ | |
45500060 JH |
4492 | if (flags > 0) |
4493 | { | |
6c1c3d1d WB |
4494 | synprot_error(L_smtp_syntax_error, 501, NULL, |
4495 | US"NOTIFY can be specified once only"); | |
4496 | goto COMMAND_LOOP; | |
4497 | } | |
45500060 JH |
4498 | if (strcmpic(value, US"NEVER") == 0) |
4499 | flags |= rf_notify_never; | |
4500 | else | |
6c1c3d1d WB |
4501 | { |
4502 | uschar *p = value; | |
4503 | while (*p != 0) | |
4504 | { | |
4505 | uschar *pp = p; | |
4506 | while (*pp != 0 && *pp != ',') pp++; | |
45500060 JH |
4507 | if (*pp == ',') *pp++ = 0; |
4508 | if (strcmpic(p, US"SUCCESS") == 0) | |
4509 | { | |
4510 | DEBUG(D_receive) debug_printf("DSN: Setting notify success\n"); | |
4511 | flags |= rf_notify_success; | |
6c1c3d1d | 4512 | } |
45500060 JH |
4513 | else if (strcmpic(p, US"FAILURE") == 0) |
4514 | { | |
4515 | DEBUG(D_receive) debug_printf("DSN: Setting notify failure\n"); | |
4516 | flags |= rf_notify_failure; | |
6c1c3d1d | 4517 | } |
45500060 JH |
4518 | else if (strcmpic(p, US"DELAY") == 0) |
4519 | { | |
4520 | DEBUG(D_receive) debug_printf("DSN: Setting notify delay\n"); | |
4521 | flags |= rf_notify_delay; | |
6c1c3d1d | 4522 | } |
45500060 JH |
4523 | else |
4524 | { | |
6c1c3d1d WB |
4525 | /* Catch any strange values */ |
4526 | synprot_error(L_smtp_syntax_error, 501, NULL, | |
4527 | US"Invalid value for NOTIFY parameter"); | |
4528 | goto COMMAND_LOOP; | |
4529 | } | |
4530 | p = pp; | |
4531 | } | |
4532 | DEBUG(D_receive) debug_printf("DSN Flags: %x\n", flags); | |
4533 | } | |
4534 | } | |
4535 | ||
4536 | /* Unknown option. Stick back the terminator characters and break | |
4537 | the loop. An error for a malformed address will occur. */ | |
4538 | ||
4539 | else | |
4540 | { | |
4541 | DEBUG(D_receive) debug_printf("Invalid RCPT option: %s : %s\n", name, value); | |
4542 | name[-1] = ' '; | |
4543 | value[-1] = '='; | |
4544 | break; | |
4545 | } | |
4546 | } | |
059ec3d9 PH |
4547 | |
4548 | /* Apply SMTP rewriting then extract the working address. Don't allow "<>" | |
4549 | as a recipient address */ | |
4550 | ||
05392bbc JH |
4551 | recipient = rewrite_existflags & rewrite_smtp |
4552 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
4553 | global_rewrite_rules) | |
4554 | : smtp_cmd_data; | |
059ec3d9 | 4555 | |
2685d6e0 JH |
4556 | if (!(recipient = parse_extract_address(recipient, &errmess, &start, &end, |
4557 | &recipient_domain, FALSE))) | |
059ec3d9 | 4558 | { |
ca86f471 | 4559 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); |
059ec3d9 PH |
4560 | rcpt_fail_count++; |
4561 | break; | |
4562 | } | |
4563 | ||
4564 | /* If the recipient address is unqualified, reject it, unless this is a | |
4565 | locally generated message. However, unqualified addresses are permitted | |
4566 | from a configured list of hosts and nets - typically when behaving as | |
4567 | MUAs rather than MTAs. Sad that SMTP is used for both types of traffic, | |
4568 | really. The flag is set at the start of the SMTP connection. | |
4569 | ||
4570 | RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always | |
4571 | assumed this meant "reserved local part", but the revision of RFC 821 and | |
4572 | friends now makes it absolutely clear that it means *mailbox*. Consequently | |
4573 | we must always qualify this address, regardless. */ | |
4574 | ||
4575 | if (recipient_domain == 0) | |
2685d6e0 JH |
4576 | if (!(recipient_domain = qualify_recipient(&recipient, smtp_cmd_data, |
4577 | US"recipient"))) | |
059ec3d9 PH |
4578 | { |
4579 | rcpt_fail_count++; | |
059ec3d9 PH |
4580 | break; |
4581 | } | |
059ec3d9 PH |
4582 | |
4583 | /* Check maximum allowed */ | |
4584 | ||
4585 | if (rcpt_count > recipients_max && recipients_max > 0) | |
4586 | { | |
4587 | if (recipients_max_reject) | |
4588 | { | |
4589 | rcpt_fail_count++; | |
4590 | smtp_printf("552 too many recipients\r\n"); | |
4591 | if (!toomany) | |
4592 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message " | |
4593 | "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE)); | |
4594 | } | |
4595 | else | |
4596 | { | |
4597 | rcpt_defer_count++; | |
4598 | smtp_printf("452 too many recipients\r\n"); | |
4599 | if (!toomany) | |
4600 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess " | |
4601 | "temporarily rejected: sender=<%s> %s", sender_address, | |
4602 | host_and_ident(TRUE)); | |
4603 | } | |
4604 | ||
4605 | toomany = TRUE; | |
4606 | break; | |
4607 | } | |
4608 | ||
4609 | /* If we have passed the threshold for rate limiting, apply the current | |
4610 | delay, and update it for next time, provided this is a limited host. */ | |
4611 | ||
4612 | if (rcpt_count > smtp_rlr_threshold && | |
4613 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
4614 | { | |
4615 | DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n", | |
4616 | smtp_delay_rcpt/1000.0); | |
4617 | millisleep((int)smtp_delay_rcpt); | |
4618 | smtp_delay_rcpt *= smtp_rlr_factor; | |
4619 | if (smtp_delay_rcpt > (double)smtp_rlr_limit) | |
4620 | smtp_delay_rcpt = (double)smtp_rlr_limit; | |
4621 | } | |
4622 | ||
4623 | /* If the MAIL ACL discarded all the recipients, we bypass ACL checking | |
a14e5636 PH |
4624 | for them. Otherwise, check the access control list for this recipient. As |
4625 | there may be a delay in this, re-check for a synchronization error | |
4626 | afterwards, unless pipelining was advertised. */ | |
059ec3d9 | 4627 | |
a14e5636 PH |
4628 | if (recipients_discarded) rc = DISCARD; else |
4629 | { | |
4630 | rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg, | |
4631 | &log_msg); | |
4632 | if (rc == OK && !pipelining_advertised && !check_sync()) | |
4633 | goto SYNC_FAILURE; | |
4634 | } | |
059ec3d9 PH |
4635 | |
4636 | /* The ACL was happy */ | |
4637 | ||
4638 | if (rc == OK) | |
4639 | { | |
4e88a19f PH |
4640 | if (user_msg == NULL) smtp_printf("250 Accepted\r\n"); |
4641 | else smtp_user_msg(US"250", user_msg); | |
059ec3d9 | 4642 | receive_add_recipient(recipient, -1); |
94431adb | 4643 | |
6c1c3d1d | 4644 | /* Set the dsn flags in the recipients_list */ |
7ade712c JH |
4645 | recipients_list[recipients_count-1].orcpt = orcpt; |
4646 | recipients_list[recipients_count-1].dsn_flags = flags; | |
6c1c3d1d | 4647 | |
7ade712c JH |
4648 | DEBUG(D_receive) debug_printf("DSN: orcpt: %s flags: %d\n", |
4649 | recipients_list[recipients_count-1].orcpt, | |
4650 | recipients_list[recipients_count-1].dsn_flags); | |
059ec3d9 PH |
4651 | } |
4652 | ||
4653 | /* The recipient was discarded */ | |
4654 | ||
4655 | else if (rc == DISCARD) | |
4656 | { | |
4e88a19f PH |
4657 | if (user_msg == NULL) smtp_printf("250 Accepted\r\n"); |
4658 | else smtp_user_msg(US"250", user_msg); | |
059ec3d9 PH |
4659 | rcpt_fail_count++; |
4660 | discarded = TRUE; | |
1f12df4d | 4661 | log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> RCPT %s: " |
059ec3d9 | 4662 | "discarded by %s ACL%s%s", host_and_ident(TRUE), |
1f12df4d | 4663 | sender_address_unrewritten? sender_address_unrewritten : sender_address, |
3ee512ff | 4664 | smtp_cmd_argument, recipients_discarded? "MAIL" : "RCPT", |
1f12df4d | 4665 | log_msg ? US": " : US"", log_msg ? log_msg : US""); |
059ec3d9 PH |
4666 | } |
4667 | ||
4668 | /* Either the ACL failed the address, or it was deferred. */ | |
4669 | ||
4670 | else | |
4671 | { | |
4672 | if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++; | |
4673 | done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg); | |
4674 | } | |
4675 | break; | |
4676 | ||
4677 | ||
4678 | /* The DATA command is legal only if it follows successful MAIL FROM | |
4679 | and RCPT TO commands. However, if pipelining is advertised, a bad DATA is | |
4680 | not counted as a protocol error if it follows RCPT (which must have been | |
4681 | rejected if there are no recipients.) This function is complete when a | |
4682 | valid DATA command is encountered. | |
4683 | ||
4684 | Note concerning the code used: RFC 2821 says this: | |
4685 | ||
4686 | - If there was no MAIL, or no RCPT, command, or all such commands | |
4687 | were rejected, the server MAY return a "command out of sequence" | |
4688 | (503) or "no valid recipients" (554) reply in response to the | |
4689 | DATA command. | |
4690 | ||
4691 | The example in the pipelining RFC 2920 uses 554, but I use 503 here | |
2679d413 PH |
4692 | because it is the same whether pipelining is in use or not. |
4693 | ||
4694 | If all the RCPT commands that precede DATA provoked the same error message | |
4695 | (often indicating some kind of system error), it is helpful to include it | |
4696 | with the DATA rejection (an idea suggested by Tony Finch). */ | |
059ec3d9 | 4697 | |
18481de3 JH |
4698 | case BDAT_CMD: |
4699 | HAD(SCH_BDAT); | |
4700 | { | |
4701 | int n; | |
4702 | ||
4703 | if (chunking_state != CHUNKING_OFFERED) | |
4704 | { | |
4705 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4706 | US"BDAT command used when CHUNKING not advertised"); | |
4707 | break; | |
4708 | } | |
4709 | ||
4710 | /* grab size, endmarker */ | |
4711 | ||
4712 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) | |
4713 | { | |
7e3ce68e | 4714 | done = synprot_error(L_smtp_protocol_error, 501, NULL, |
18481de3 JH |
4715 | US"missing size for BDAT command"); |
4716 | break; | |
4717 | } | |
4718 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
4719 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
7e3ce68e JH |
4720 | chunking_data_left = chunking_datasize; |
4721 | ||
4722 | lwr_receive_getc = receive_getc; | |
4723 | lwr_receive_ungetc = receive_ungetc; | |
4724 | receive_getc = bdat_getc; | |
4725 | receive_ungetc = bdat_ungetc; | |
18481de3 JH |
4726 | |
4727 | DEBUG(D_any) | |
4728 | debug_printf("chunking state %d\n", (int)chunking_state); | |
4729 | goto DATA_BDAT; | |
4730 | } | |
4731 | ||
059ec3d9 | 4732 | case DATA_CMD: |
b4ed4da0 | 4733 | HAD(SCH_DATA); |
18481de3 JH |
4734 | |
4735 | DATA_BDAT: /* Common code for DATA and BDAT */ | |
059ec3d9 PH |
4736 | if (!discarded && recipients_count <= 0) |
4737 | { | |
2679d413 PH |
4738 | if (rcpt_smtp_response_same && rcpt_smtp_response != NULL) |
4739 | { | |
4740 | uschar *code = US"503"; | |
4741 | int len = Ustrlen(rcpt_smtp_response); | |
4742 | smtp_respond(code, 3, FALSE, US"All RCPT commands were rejected with " | |
4743 | "this error:"); | |
4744 | /* Responses from smtp_printf() will have \r\n on the end */ | |
4745 | if (len > 2 && rcpt_smtp_response[len-2] == '\r') | |
4746 | rcpt_smtp_response[len-2] = 0; | |
4747 | smtp_respond(code, 3, FALSE, rcpt_smtp_response); | |
4748 | } | |
059ec3d9 | 4749 | if (pipelining_advertised && last_was_rcpt) |
18481de3 JH |
4750 | smtp_printf("503 Valid RCPT command must precede %s\r\n", |
4751 | smtp_names[smtp_connection_had[smtp_ch_index-1]]); | |
059ec3d9 PH |
4752 | else |
4753 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
18481de3 JH |
4754 | smtp_connection_had[smtp_ch_index-1] == SCH_DATA |
4755 | ? US"valid RCPT command must precede DATA" | |
4756 | : US"valid RCPT command must precede BDAT"); | |
059ec3d9 PH |
4757 | break; |
4758 | } | |
4759 | ||
4760 | if (toomany && recipients_max_reject) | |
4761 | { | |
4762 | sender_address = NULL; /* This will allow a new MAIL without RSET */ | |
4763 | sender_address_unrewritten = NULL; | |
4764 | smtp_printf("554 Too many recipients\r\n"); | |
4765 | break; | |
4766 | } | |
8e669ac1 | 4767 | |
7e3ce68e JH |
4768 | if (chunking_state > CHUNKING_OFFERED) |
4769 | { /* No predata ACL or go-ahead output for BDAT */ | |
18481de3 | 4770 | rc = OK; |
18481de3 | 4771 | } |
18481de3 | 4772 | else |
8e669ac1 | 4773 | { |
7e3ce68e JH |
4774 | /* If there is an ACL, re-check the synchronization afterwards, since the |
4775 | ACL may have delayed. To handle cutthrough delivery enforce a dummy call | |
4776 | to get the DATA command sent. */ | |
059ec3d9 | 4777 | |
7e3ce68e JH |
4778 | if (acl_smtp_predata == NULL && cutthrough.fd < 0) |
4779 | rc = OK; | |
4780 | else | |
4781 | { | |
4782 | uschar * acl = acl_smtp_predata ? acl_smtp_predata : US"accept"; | |
4783 | enable_dollar_recipients = TRUE; | |
4784 | rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg, | |
4785 | &log_msg); | |
4786 | enable_dollar_recipients = FALSE; | |
4787 | if (rc == OK && !check_sync()) | |
4788 | goto SYNC_FAILURE; | |
4789 | ||
4790 | if (rc != OK) | |
4791 | { /* Either the ACL failed the address, or it was deferred. */ | |
4792 | done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg); | |
4793 | break; | |
4794 | } | |
4795 | } | |
4796 | ||
4797 | if (user_msg) | |
4798 | smtp_user_msg(US"354", user_msg); | |
4799 | else | |
4800 | smtp_printf( | |
4801 | "354 Enter message, ending with \".\" on a line by itself\r\n"); | |
059ec3d9 PH |
4802 | } |
4803 | ||
7e3ce68e JH |
4804 | done = 3; |
4805 | message_ended = END_NOTENDED; /* Indicate in middle of data */ | |
059ec3d9 | 4806 | |
059ec3d9 PH |
4807 | break; |
4808 | ||
4809 | ||
4810 | case VRFY_CMD: | |
059ec3d9 | 4811 | { |
4f6ae5c3 | 4812 | uschar * address; |
059ec3d9 | 4813 | |
4f6ae5c3 | 4814 | HAD(SCH_VRFY); |
059ec3d9 | 4815 | |
05392bbc JH |
4816 | if (!(address = parse_extract_address(smtp_cmd_data, &errmess, |
4817 | &start, &end, &recipient_domain, FALSE))) | |
4818 | { | |
4f6ae5c3 | 4819 | smtp_printf("501 %s\r\n", errmess); |
05392bbc JH |
4820 | break; |
4821 | } | |
4822 | ||
4823 | if (recipient_domain == 0) | |
2685d6e0 JH |
4824 | if (!(recipient_domain = qualify_recipient(&address, smtp_cmd_data, |
4825 | US"verify"))) | |
05392bbc | 4826 | break; |
4f6ae5c3 | 4827 | |
05392bbc | 4828 | if ((rc = acl_check(ACL_WHERE_VRFY, address, acl_smtp_vrfy, |
4f6ae5c3 JH |
4829 | &user_msg, &log_msg)) != OK) |
4830 | done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg); | |
059ec3d9 | 4831 | else |
4f6ae5c3 | 4832 | { |
05392bbc JH |
4833 | uschar * s = NULL; |
4834 | address_item * addr = deliver_make_addr(address, FALSE); | |
059ec3d9 | 4835 | |
4f6ae5c3 JH |
4836 | switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1, |
4837 | -1, -1, NULL, NULL, NULL)) | |
4838 | { | |
4839 | case OK: | |
4840 | s = string_sprintf("250 <%s> is deliverable", address); | |
4841 | break; | |
059ec3d9 | 4842 | |
4f6ae5c3 JH |
4843 | case DEFER: |
4844 | s = (addr->user_message != NULL)? | |
4845 | string_sprintf("451 <%s> %s", address, addr->user_message) : | |
4846 | string_sprintf("451 Cannot resolve <%s> at this time", address); | |
4847 | break; | |
059ec3d9 | 4848 | |
4f6ae5c3 JH |
4849 | case FAIL: |
4850 | s = (addr->user_message != NULL)? | |
4851 | string_sprintf("550 <%s> %s", address, addr->user_message) : | |
4852 | string_sprintf("550 <%s> is not deliverable", address); | |
4853 | log_write(0, LOG_MAIN, "VRFY failed for %s %s", | |
4854 | smtp_cmd_argument, host_and_ident(TRUE)); | |
4855 | break; | |
4856 | } | |
4857 | ||
4858 | smtp_printf("%s\r\n", s); | |
4859 | } | |
4860 | break; | |
059ec3d9 | 4861 | } |
059ec3d9 PH |
4862 | |
4863 | ||
4864 | case EXPN_CMD: | |
b4ed4da0 | 4865 | HAD(SCH_EXPN); |
64ffc24f | 4866 | rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg); |
059ec3d9 PH |
4867 | if (rc != OK) |
4868 | done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg); | |
4869 | else | |
4870 | { | |
4871 | BOOL save_log_testing_mode = log_testing_mode; | |
4872 | address_test_mode = log_testing_mode = TRUE; | |
ca86f471 | 4873 | (void) verify_address(deliver_make_addr(smtp_cmd_data, FALSE), |
64ffc24f PH |
4874 | smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1, |
4875 | NULL, NULL, NULL); | |
059ec3d9 PH |
4876 | address_test_mode = FALSE; |
4877 | log_testing_mode = save_log_testing_mode; /* true for -bh */ | |
4878 | } | |
4879 | break; | |
4880 | ||
4881 | ||
4882 | #ifdef SUPPORT_TLS | |
4883 | ||
4884 | case STARTTLS_CMD: | |
b4ed4da0 | 4885 | HAD(SCH_STARTTLS); |
059ec3d9 PH |
4886 | if (!tls_advertised) |
4887 | { | |
4888 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4889 | US"STARTTLS command used when not advertised"); | |
4890 | break; | |
4891 | } | |
4892 | ||
4893 | /* Apply an ACL check if one is defined */ | |
4894 | ||
4f6ae5c3 JH |
4895 | if ( acl_smtp_starttls |
4896 | && (rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls, | |
4897 | &user_msg, &log_msg)) != OK | |
4898 | ) | |
059ec3d9 | 4899 | { |
4f6ae5c3 JH |
4900 | done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg); |
4901 | break; | |
059ec3d9 PH |
4902 | } |
4903 | ||
4904 | /* RFC 2487 is not clear on when this command may be sent, though it | |
4905 | does state that all information previously obtained from the client | |
4906 | must be discarded if a TLS session is started. It seems reasonble to | |
4907 | do an implied RSET when STARTTLS is received. */ | |
4908 | ||
4909 | incomplete_transaction_log(US"STARTTLS"); | |
4910 | smtp_reset(reset_point); | |
4911 | toomany = FALSE; | |
4912 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = FALSE; | |
4913 | ||
da80c2a8 PP |
4914 | /* There's an attack where more data is read in past the STARTTLS command |
4915 | before TLS is negotiated, then assumed to be part of the secure session | |
4916 | when used afterwards; we use segregated input buffers, so are not | |
4917 | vulnerable, but we want to note when it happens and, for sheer paranoia, | |
4918 | ensure that the buffer is "wiped". | |
4919 | Pipelining sync checks will normally have protected us too, unless disabled | |
4920 | by configuration. */ | |
4921 | ||
4922 | if (receive_smtp_buffered()) | |
4923 | { | |
4924 | DEBUG(D_any) | |
18481de3 | 4925 | debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n"); |
817d9f57 | 4926 | if (tls_in.active < 0) |
da80c2a8 PP |
4927 | smtp_inend = smtp_inptr = smtp_inbuffer; |
4928 | /* and if TLS is already active, tls_server_start() should fail */ | |
4929 | } | |
4930 | ||
4e7ee012 PP |
4931 | /* There is nothing we value in the input buffer and if TLS is succesfully |
4932 | negotiated, we won't use this buffer again; if TLS fails, we'll just read | |
4933 | fresh content into it. The buffer contains arbitrary content from an | |
4934 | untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n | |
4935 | It seems safest to just wipe away the content rather than leave it as a | |
4936 | target to jump to. */ | |
4937 | ||
4938 | memset(smtp_inbuffer, 0, in_buffer_size); | |
4939 | ||
059ec3d9 PH |
4940 | /* Attempt to start up a TLS session, and if successful, discard all |
4941 | knowledge that was obtained previously. At least, that's what the RFC says, | |
4942 | and that's what happens by default. However, in order to work round YAEB, | |
4943 | there is an option to remember the esmtp state. Sigh. | |
4944 | ||
4945 | We must allow for an extra EHLO command and an extra AUTH command after | |
4946 | STARTTLS that don't add to the nonmail command count. */ | |
4947 | ||
17c76198 | 4948 | if ((rc = tls_server_start(tls_require_ciphers)) == OK) |
059ec3d9 PH |
4949 | { |
4950 | if (!tls_remember_esmtp) | |
4951 | helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE; | |
4952 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
4953 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE; | |
b3ef41c9 | 4954 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; |
059ec3d9 PH |
4955 | if (sender_helo_name != NULL) |
4956 | { | |
4957 | store_free(sender_helo_name); | |
4958 | sender_helo_name = NULL; | |
4959 | host_build_sender_fullhost(); /* Rebuild */ | |
4960 | set_process_info("handling incoming TLS connection from %s", | |
4961 | host_and_ident(FALSE)); | |
4962 | } | |
e524074d JH |
4963 | received_protocol = |
4964 | (sender_host_address ? protocols : protocols_local) | |
4965 | [ (esmtp | |
4966 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
4967 | : pnormal) | |
4968 | + (tls_in.active >= 0 ? pcrpted : 0) | |
4969 | ]; | |
059ec3d9 PH |
4970 | |
4971 | sender_host_authenticated = NULL; | |
4972 | authenticated_id = NULL; | |
4973 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; | |
4974 | DEBUG(D_tls) debug_printf("TLS active\n"); | |
4975 | break; /* Successful STARTTLS */ | |
4976 | } | |
4977 | ||
4978 | /* Some local configuration problem was discovered before actually trying | |
4979 | to do a TLS handshake; give a temporary error. */ | |
4980 | ||
4981 | else if (rc == DEFER) | |
4982 | { | |
4983 | smtp_printf("454 TLS currently unavailable\r\n"); | |
4984 | break; | |
4985 | } | |
4986 | ||
4987 | /* Hard failure. Reject everything except QUIT or closed connection. One | |
817d9f57 | 4988 | cause for failure is a nested STARTTLS, in which case tls_in.active remains |
059ec3d9 PH |
4989 | set, but we must still reject all incoming commands. */ |
4990 | ||
4991 | DEBUG(D_tls) debug_printf("TLS failed to start\n"); | |
4992 | while (done <= 0) | |
4993 | { | |
4994 | switch(smtp_read_command(FALSE)) | |
4995 | { | |
4996 | case EOF_CMD: | |
4997 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF", | |
4998 | smtp_get_connection_info()); | |
8f128379 | 4999 | smtp_notquit_exit(US"tls-failed", NULL, NULL); |
059ec3d9 PH |
5000 | done = 2; |
5001 | break; | |
5002 | ||
8f128379 | 5003 | /* It is perhaps arguable as to which exit ACL should be called here, |
24f66b4d | 5004 | but as it is probably a situation that almost never arises, it |
8f128379 PH |
5005 | probably doesn't matter. We choose to call the real QUIT ACL, which in |
5006 | some sense is perhaps "right". */ | |
5007 | ||
059ec3d9 | 5008 | case QUIT_CMD: |
8f128379 PH |
5009 | user_msg = NULL; |
5010 | if (acl_smtp_quit != NULL) | |
5011 | { | |
5012 | rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, | |
5013 | &log_msg); | |
5014 | if (rc == ERROR) | |
5015 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
5016 | log_msg); | |
5017 | } | |
5018 | if (user_msg == NULL) | |
5019 | smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); | |
5020 | else | |
5021 | smtp_respond(US"221", 3, TRUE, user_msg); | |
059ec3d9 PH |
5022 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", |
5023 | smtp_get_connection_info()); | |
5024 | done = 2; | |
5025 | break; | |
5026 | ||
5027 | default: | |
5028 | smtp_printf("554 Security failure\r\n"); | |
5029 | break; | |
5030 | } | |
5031 | } | |
817d9f57 | 5032 | tls_close(TRUE, TRUE); |
059ec3d9 PH |
5033 | break; |
5034 | #endif | |
5035 | ||
5036 | ||
5037 | /* The ACL for QUIT is provided for gathering statistical information or | |
5038 | similar; it does not affect the response code, but it can supply a custom | |
5039 | message. */ | |
5040 | ||
5041 | case QUIT_CMD: | |
7e3ce68e | 5042 | smtp_quit_handler(&user_msg, &log_msg); |
059ec3d9 | 5043 | done = 2; |
059ec3d9 PH |
5044 | break; |
5045 | ||
5046 | ||
5047 | case RSET_CMD: | |
7e3ce68e | 5048 | smtp_rset_handler(); |
059ec3d9 PH |
5049 | smtp_reset(reset_point); |
5050 | toomany = FALSE; | |
059ec3d9 PH |
5051 | break; |
5052 | ||
5053 | ||
5054 | case NOOP_CMD: | |
b4ed4da0 | 5055 | HAD(SCH_NOOP); |
059ec3d9 PH |
5056 | smtp_printf("250 OK\r\n"); |
5057 | break; | |
5058 | ||
5059 | ||
b43a74ea PH |
5060 | /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually |
5061 | used, a check will be done for permitted hosts. Show STARTTLS only if not | |
5062 | already in a TLS session and if it would be advertised in the EHLO | |
5063 | response. */ | |
059ec3d9 PH |
5064 | |
5065 | case HELP_CMD: | |
b4ed4da0 | 5066 | HAD(SCH_HELP); |
059ec3d9 PH |
5067 | smtp_printf("214-Commands supported:\r\n"); |
5068 | { | |
5069 | uschar buffer[256]; | |
5070 | buffer[0] = 0; | |
5071 | Ustrcat(buffer, " AUTH"); | |
5072 | #ifdef SUPPORT_TLS | |
817d9f57 | 5073 | if (tls_in.active < 0 && |
b43a74ea PH |
5074 | verify_check_host(&tls_advertise_hosts) != FAIL) |
5075 | Ustrcat(buffer, " STARTTLS"); | |
059ec3d9 | 5076 | #endif |
7e3ce68e | 5077 | Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA BDAT"); |
059ec3d9 PH |
5078 | Ustrcat(buffer, " NOOP QUIT RSET HELP"); |
5079 | if (acl_smtp_etrn != NULL) Ustrcat(buffer, " ETRN"); | |
5080 | if (acl_smtp_expn != NULL) Ustrcat(buffer, " EXPN"); | |
5081 | if (acl_smtp_vrfy != NULL) Ustrcat(buffer, " VRFY"); | |
5082 | smtp_printf("214%s\r\n", buffer); | |
5083 | } | |
5084 | break; | |
5085 | ||
5086 | ||
5087 | case EOF_CMD: | |
5088 | incomplete_transaction_log(US"connection lost"); | |
8f128379 PH |
5089 | smtp_notquit_exit(US"connection-lost", US"421", |
5090 | US"%s lost input connection", smtp_active_hostname); | |
059ec3d9 PH |
5091 | |
5092 | /* Don't log by default unless in the middle of a message, as some mailers | |
5093 | just drop the call rather than sending QUIT, and it clutters up the logs. | |
5094 | */ | |
5095 | ||
5096 | if (sender_address != NULL || recipients_count > 0) | |
5097 | log_write(L_lost_incoming_connection, | |
5098 | LOG_MAIN, | |
5099 | "unexpected %s while reading SMTP command from %s%s", | |
5100 | sender_host_unknown? "EOF" : "disconnection", | |
5101 | host_and_ident(FALSE), smtp_read_error); | |
5102 | ||
5103 | else log_write(L_smtp_connection, LOG_MAIN, "%s lost%s", | |
5104 | smtp_get_connection_info(), smtp_read_error); | |
5105 | ||
5106 | done = 1; | |
5107 | break; | |
5108 | ||
5109 | ||
5110 | case ETRN_CMD: | |
b4ed4da0 | 5111 | HAD(SCH_ETRN); |
059ec3d9 PH |
5112 | if (sender_address != NULL) |
5113 | { | |
5114 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5115 | US"ETRN is not permitted inside a transaction"); | |
5116 | break; | |
5117 | } | |
5118 | ||
3ee512ff | 5119 | log_write(L_etrn, LOG_MAIN, "ETRN %s received from %s", smtp_cmd_argument, |
059ec3d9 PH |
5120 | host_and_ident(FALSE)); |
5121 | ||
4f6ae5c3 JH |
5122 | if ((rc = acl_check(ACL_WHERE_ETRN, NULL, acl_smtp_etrn, |
5123 | &user_msg, &log_msg)) != OK) | |
059ec3d9 PH |
5124 | { |
5125 | done = smtp_handle_acl_fail(ACL_WHERE_ETRN, rc, user_msg, log_msg); | |
5126 | break; | |
5127 | } | |
5128 | ||
5129 | /* Compute the serialization key for this command. */ | |
5130 | ||
ca86f471 | 5131 | etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_cmd_data); |
059ec3d9 PH |
5132 | |
5133 | /* If a command has been specified for running as a result of ETRN, we | |
5134 | permit any argument to ETRN. If not, only the # standard form is permitted, | |
5135 | since that is strictly the only kind of ETRN that can be implemented | |
5136 | according to the RFC. */ | |
5137 | ||
5138 | if (smtp_etrn_command != NULL) | |
5139 | { | |
5140 | uschar *error; | |
5141 | BOOL rc; | |
5142 | etrn_command = smtp_etrn_command; | |
ca86f471 | 5143 | deliver_domain = smtp_cmd_data; |
059ec3d9 PH |
5144 | rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL, |
5145 | US"ETRN processing", &error); | |
5146 | deliver_domain = NULL; | |
5147 | if (!rc) | |
5148 | { | |
5149 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to set up ETRN command: %s", | |
5150 | error); | |
5151 | smtp_printf("458 Internal failure\r\n"); | |
5152 | break; | |
5153 | } | |
5154 | } | |
5155 | ||
5156 | /* Else set up to call Exim with the -R option. */ | |
5157 | ||
5158 | else | |
5159 | { | |
ca86f471 | 5160 | if (*smtp_cmd_data++ != '#') |
059ec3d9 PH |
5161 | { |
5162 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5163 | US"argument must begin with #"); | |
5164 | break; | |
5165 | } | |
5166 | etrn_command = US"exim -R"; | |
e37f8a84 JH |
5167 | argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, |
5168 | *queue_name ? 4 : 2, | |
5169 | US"-R", smtp_cmd_data, | |
5170 | US"-MCG", queue_name); | |
059ec3d9 PH |
5171 | } |
5172 | ||
5173 | /* If we are host-testing, don't actually do anything. */ | |
5174 | ||
5175 | if (host_checking) | |
5176 | { | |
5177 | HDEBUG(D_any) | |
5178 | { | |
5179 | debug_printf("ETRN command is: %s\n", etrn_command); | |
5180 | debug_printf("ETRN command execution skipped\n"); | |
5181 | } | |
4e88a19f PH |
5182 | if (user_msg == NULL) smtp_printf("250 OK\r\n"); |
5183 | else smtp_user_msg(US"250", user_msg); | |
059ec3d9 PH |
5184 | break; |
5185 | } | |
5186 | ||
5187 | ||
5188 | /* If ETRN queue runs are to be serialized, check the database to | |
5189 | ensure one isn't already running. */ | |
5190 | ||
e8ae7214 | 5191 | if (smtp_etrn_serialize && !enq_start(etrn_serialize_key, 1)) |
059ec3d9 | 5192 | { |
ca86f471 | 5193 | smtp_printf("458 Already processing %s\r\n", smtp_cmd_data); |
059ec3d9 PH |
5194 | break; |
5195 | } | |
5196 | ||
5197 | /* Fork a child process and run the command. We don't want to have to | |
5198 | wait for the process at any point, so set SIGCHLD to SIG_IGN before | |
5199 | forking. It should be set that way anyway for external incoming SMTP, | |
5200 | but we save and restore to be tidy. If serialization is required, we | |
5201 | actually run the command in yet another process, so we can wait for it | |
5202 | to complete and then remove the serialization lock. */ | |
5203 | ||
5204 | oldsignal = signal(SIGCHLD, SIG_IGN); | |
5205 | ||
5206 | if ((pid = fork()) == 0) | |
5207 | { | |
f1e894f3 PH |
5208 | smtp_input = FALSE; /* This process is not associated with the */ |
5209 | (void)fclose(smtp_in); /* SMTP call any more. */ | |
5210 | (void)fclose(smtp_out); | |
059ec3d9 PH |
5211 | |
5212 | signal(SIGCHLD, SIG_DFL); /* Want to catch child */ | |
5213 | ||
5214 | /* If not serializing, do the exec right away. Otherwise, fork down | |
5215 | into another process. */ | |
5216 | ||
5217 | if (!smtp_etrn_serialize || (pid = fork()) == 0) | |
5218 | { | |
5219 | DEBUG(D_exec) debug_print_argv(argv); | |
5220 | exim_nullstd(); /* Ensure std{in,out,err} exist */ | |
5221 | execv(CS argv[0], (char *const *)argv); | |
5222 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "exec of \"%s\" (ETRN) failed: %s", | |
5223 | etrn_command, strerror(errno)); | |
5224 | _exit(EXIT_FAILURE); /* paranoia */ | |
5225 | } | |
5226 | ||
5227 | /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That | |
5228 | is, we are in the first subprocess, after forking again. All we can do | |
5229 | for a failing fork is to log it. Otherwise, wait for the 2nd process to | |
5230 | complete, before removing the serialization. */ | |
5231 | ||
5232 | if (pid < 0) | |
5233 | log_write(0, LOG_MAIN|LOG_PANIC, "2nd fork for serialized ETRN " | |
5234 | "failed: %s", strerror(errno)); | |
5235 | else | |
5236 | { | |
5237 | int status; | |
5238 | DEBUG(D_any) debug_printf("waiting for serialized ETRN process %d\n", | |
5239 | (int)pid); | |
5240 | (void)wait(&status); | |
5241 | DEBUG(D_any) debug_printf("serialized ETRN process %d ended\n", | |
5242 | (int)pid); | |
5243 | } | |
5244 | ||
5245 | enq_end(etrn_serialize_key); | |
5246 | _exit(EXIT_SUCCESS); | |
5247 | } | |
5248 | ||
5249 | /* Back in the top level SMTP process. Check that we started a subprocess | |
5250 | and restore the signal state. */ | |
5251 | ||
5252 | if (pid < 0) | |
5253 | { | |
5254 | log_write(0, LOG_MAIN|LOG_PANIC, "fork of process for ETRN failed: %s", | |
5255 | strerror(errno)); | |
5256 | smtp_printf("458 Unable to fork process\r\n"); | |
5257 | if (smtp_etrn_serialize) enq_end(etrn_serialize_key); | |
5258 | } | |
4e88a19f PH |
5259 | else |
5260 | { | |
5261 | if (user_msg == NULL) smtp_printf("250 OK\r\n"); | |
5262 | else smtp_user_msg(US"250", user_msg); | |
5263 | } | |
059ec3d9 PH |
5264 | |
5265 | signal(SIGCHLD, oldsignal); | |
5266 | break; | |
5267 | ||
5268 | ||
5269 | case BADARG_CMD: | |
5270 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5271 | US"unexpected argument data"); | |
5272 | break; | |
5273 | ||
5274 | ||
5275 | /* This currently happens only for NULLs, but could be extended. */ | |
5276 | ||
5277 | case BADCHAR_CMD: | |
5278 | done = synprot_error(L_smtp_syntax_error, 0, NULL, /* Just logs */ | |
5279 | US"NULL character(s) present (shown as '?')"); | |
5280 | smtp_printf("501 NULL characters are not allowed in SMTP commands\r\n"); | |
5281 | break; | |
5282 | ||
5283 | ||
5284 | case BADSYN_CMD: | |
a14e5636 | 5285 | SYNC_FAILURE: |
059ec3d9 PH |
5286 | if (smtp_inend >= smtp_inbuffer + in_buffer_size) |
5287 | smtp_inend = smtp_inbuffer + in_buffer_size - 1; | |
5288 | c = smtp_inend - smtp_inptr; | |
5289 | if (c > 150) c = 150; | |
5290 | smtp_inptr[c] = 0; | |
5291 | incomplete_transaction_log(US"sync failure"); | |
3af76a81 | 5292 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error " |
059ec3d9 PH |
5293 | "(next input sent too soon: pipelining was%s advertised): " |
5294 | "rejected \"%s\" %s next input=\"%s\"", | |
5295 | pipelining_advertised? "" : " not", | |
3ee512ff | 5296 | smtp_cmd_buffer, host_and_ident(TRUE), |
059ec3d9 | 5297 | string_printing(smtp_inptr)); |
8f128379 PH |
5298 | smtp_notquit_exit(US"synchronization-error", US"554", |
5299 | US"SMTP synchronization error"); | |
059ec3d9 PH |
5300 | done = 1; /* Pretend eof - drops connection */ |
5301 | break; | |
5302 | ||
5303 | ||
5304 | case TOO_MANY_NONMAIL_CMD: | |
ca86f471 PH |
5305 | s = smtp_cmd_buffer; |
5306 | while (*s != 0 && !isspace(*s)) s++; | |
059ec3d9 PH |
5307 | incomplete_transaction_log(US"too many non-mail commands"); |
5308 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5309 | "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE), | |
6d9cfc47 | 5310 | (int)(s - smtp_cmd_buffer), smtp_cmd_buffer); |
8f128379 | 5311 | smtp_notquit_exit(US"bad-commands", US"554", US"Too many nonmail commands"); |
059ec3d9 PH |
5312 | done = 1; /* Pretend eof - drops connection */ |
5313 | break; | |
5314 | ||
cee5f132 | 5315 | #ifdef SUPPORT_PROXY |
a3c86431 TL |
5316 | case PROXY_FAIL_IGNORE_CMD: |
5317 | smtp_printf("503 Command refused, required Proxy negotiation failed\r\n"); | |
5318 | break; | |
cee5f132 | 5319 | #endif |
059ec3d9 PH |
5320 | |
5321 | default: | |
5322 | if (unknown_command_count++ >= smtp_max_unknown_commands) | |
5323 | { | |
5324 | log_write(L_smtp_syntax_error, LOG_MAIN, | |
5325 | "SMTP syntax error in \"%s\" %s %s", | |
3ee512ff | 5326 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), |
059ec3d9 PH |
5327 | US"unrecognized command"); |
5328 | incomplete_transaction_log(US"unrecognized command"); | |
8f128379 PH |
5329 | smtp_notquit_exit(US"bad-commands", US"500", |
5330 | US"Too many unrecognized commands"); | |
059ec3d9 PH |
5331 | done = 2; |
5332 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5333 | "unrecognized commands (last was \"%s\")", host_and_ident(FALSE), | |
0ebc4d69 | 5334 | string_printing(smtp_cmd_buffer)); |
059ec3d9 PH |
5335 | } |
5336 | else | |
5337 | done = synprot_error(L_smtp_syntax_error, 500, NULL, | |
5338 | US"unrecognized command"); | |
5339 | break; | |
5340 | } | |
5341 | ||
5342 | /* This label is used by goto's inside loops that want to break out to | |
5343 | the end of the command-processing loop. */ | |
5344 | ||
5345 | COMMAND_LOOP: | |
5346 | last_was_rej_mail = was_rej_mail; /* Remember some last commands for */ | |
5347 | last_was_rcpt = was_rcpt; /* protocol error handling */ | |
5348 | continue; | |
5349 | } | |
5350 | ||
5351 | return done - 2; /* Convert yield values */ | |
5352 | } | |
5353 | ||
e45a1c37 JH |
5354 | /* vi: aw ai sw=2 |
5355 | */ | |
059ec3d9 | 5356 | /* End of smtp_in.c */ |