Add $smtp_command_history variable
[exim.git] / src / src / smtp_in.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
d4e5e70b 5/* Copyright (c) University of Cambridge 1995 - 2017 */
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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>
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13
14
15/* Initialize for TCP wrappers if so configured. It appears that the macro
16HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before
17including 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
31int allow_severity = LOG_INFO;
32int deny_severity = LOG_NOTICE;
5dc43717 33uschar *tcp_wrappers_name;
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34#endif
35
36
8d67ada3
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37/* Size of buffer for reading SMTP commands. We used to use 512, as defined
38by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
39commands that accept arguments, and this in particular applies to AUTH, where
94431adb 40the data can be quite long. More recently this value was 2048 in Exim;
e2ca7082 41however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients
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42such as Thunderbird will send an AUTH with an initial-response for GSSAPI.
43The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and
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44we need room to handle large base64-encoded AUTHs for GSSAPI.
45*/
46
bd8fbe36 47#define SMTP_CMD_BUFFER_SIZE 16384
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48
49/* Size of buffer for reading SMTP incoming packets */
50
bd8fbe36 51#define IN_BUFFER_SIZE 8192
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52
53/* Structure for SMTP command list */
54
55typedef struct {
1ba28e2b 56 const char *name;
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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
64are those for which synchronization is always required. Checking this can help
65block some spam. */
66
67enum {
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 */
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76
77 /* This is a dummy to identify the non-sync commands when pipelining */
78
79 NON_SYNC_CMD_PIPELINING,
80
81 /* These commands need not be synchronized when pipelining */
82
83 MAIL_CMD, RCPT_CMD, RSET_CMD,
84
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85 /* This is a dummy to identify the non-sync commands when not pipelining */
86
87 NON_SYNC_CMD_NON_PIPELINING,
88
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89 /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and
90 processed the message is sent using a series of BDAT commands"
91 implies that BDAT should be synchronized. However, we see Google, at least,
92 sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for
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93 processing of the RCPT response(s). We shall do the same, and not require
94 synch for BDAT. Worse, as the chunk may (very likely will) follow the
95 command-header in the same packet we cannot do the usual "is there any
4c04137d 96 follow-on data after the command line" even for non-pipeline mode.
f4630439 97 So we'll need an explicit check after reading the expected chunk amount
4c04137d 98 when non-pipe, before sending the ACK. */
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99
100 BDAT_CMD,
101
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102 /* I have been unable to find a statement about the use of pipelining
103 with AUTH, so to be on the safe side it is here, though I kind of feel
104 it should be up there with the synchronized commands. */
105
106 AUTH_CMD,
107
108 /* I'm not sure about these, but I don't think they matter. */
109
110 QUIT_CMD, HELP_CMD,
111
cee5f132 112#ifdef SUPPORT_PROXY
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113 PROXY_FAIL_IGNORE_CMD,
114#endif
115
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116 /* These are specials that don't correspond to actual commands */
117
118 EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD,
119 TOO_MANY_NONMAIL_CMD };
120
121
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122/* This is a convenience macro for adding the identity of an SMTP command
123to the circular buffer that holds a list of the last n received. */
124
125#define HAD(n) \
126 smtp_connection_had[smtp_ch_index++] = n; \
127 if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
128
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129
130/*************************************************
131* Local static variables *
132*************************************************/
133
134static auth_instance *authenticated_by;
135static BOOL auth_advertised;
136#ifdef SUPPORT_TLS
137static BOOL tls_advertised;
138#endif
6c1c3d1d 139static BOOL dsn_advertised;
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140static BOOL esmtp;
141static BOOL helo_required = FALSE;
142static BOOL helo_verify = FALSE;
143static BOOL helo_seen;
144static BOOL helo_accept_junk;
145static BOOL count_nonmail;
146static BOOL pipelining_advertised;
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147static BOOL rcpt_smtp_response_same;
148static BOOL rcpt_in_progress;
059ec3d9 149static int nonmail_command_count;
8f128379 150static BOOL smtp_exit_function_called = 0;
8c5d388a 151#ifdef SUPPORT_I18N
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152static BOOL smtputf8_advertised;
153#endif
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154static int synprot_error_count;
155static int unknown_command_count;
156static int sync_cmd_limit;
157static int smtp_write_error = 0;
158
2679d413 159static uschar *rcpt_smtp_response;
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160static uschar *smtp_data_buffer;
161static uschar *smtp_cmd_data;
162
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163/* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
164final fields of all except AUTH are forced TRUE at the start of a new message
165setup, to allow one of each between messages that is not counted as a nonmail
166command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to
167allow a new EHLO after starting up TLS.
168
169AUTH is "falsely" labelled as a mail command initially, so that it doesn't get
170counted. However, the flag is changed when AUTH is received, so that multiple
171failing AUTHs will eventually hit the limit. After a successful AUTH, another
172AUTH is already forbidden. After a TLS session is started, AUTH's flag is again
173forced TRUE, to allow for the re-authentication that can happen at that point.
174
175QUIT is also "falsely" labelled as a mail command so that it doesn't up the
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176count of non-mail commands and possibly provoke an error.
177
178tls_auth is a pseudo-command, never expected in input. It is activated
179on TLS startup and looks for a tls authenticator. */
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180
181static smtp_cmd_list cmd_list[] = {
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182 /* name len cmd has_arg is_mail_cmd */
183
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184 { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */
185 { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE },
186 { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE },
187 { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
188 #ifdef SUPPORT_TLS
189 { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
b3ef41c9 190 { "tls_auth", 0, TLS_AUTH_CMD, FALSE, TRUE },
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191 #endif
192
193/* If you change anything above here, also fix the definitions below. */
194
195 { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE },
196 { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE },
197 { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE },
18481de3 198 { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE },
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199 { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE },
200 { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE },
201 { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE },
202 { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE },
203 { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE },
204 { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE }
205};
206
207static smtp_cmd_list *cmd_list_end =
208 cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list);
209
210#define CMD_LIST_RSET 0
211#define CMD_LIST_HELO 1
212#define CMD_LIST_EHLO 2
213#define CMD_LIST_AUTH 3
214#define CMD_LIST_STARTTLS 4
b3ef41c9 215#define CMD_LIST_TLS_AUTH 5
059ec3d9 216
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217/* This list of names is used for performing the smtp_no_mail logging action.
218It must be kept in step with the SCH_xxx enumerations. */
219
220static uschar *smtp_names[] =
221 {
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222 US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN",
223 US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET",
224 US"STARTTLS", US"VRFY" };
b4ed4da0 225
e524074d 226static uschar *protocols_local[] = {
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227 US"local-smtp", /* HELO */
228 US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
229 US"local-esmtp", /* EHLO */
230 US"local-esmtps", /* EHLO->STARTTLS->EHLO */
231 US"local-esmtpa", /* EHLO->AUTH */
232 US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
059ec3d9 233 };
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234static uschar *protocols[] = {
235 US"smtp", /* HELO */
236 US"smtps", /* The rare case EHLO->STARTTLS->HELO */
237 US"esmtp", /* EHLO */
238 US"esmtps", /* EHLO->STARTTLS->EHLO */
239 US"esmtpa", /* EHLO->AUTH */
240 US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
241 };
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242
243#define pnormal 0
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244#define pextend 2
245#define pcrpted 1 /* added to pextend or pnormal */
246#define pauthed 2 /* added to pextend */
059ec3d9 247
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248/* Sanity check and validate optional args to MAIL FROM: envelope */
249enum {
2ef7ed08 250 ENV_MAIL_OPT_NULL,
d27f98fe 251 ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH,
8ccd00b1 252#ifndef DISABLE_PRDR
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253 ENV_MAIL_OPT_PRDR,
254#endif
6c1c3d1d 255 ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID,
8c5d388a 256#ifdef SUPPORT_I18N
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257 ENV_MAIL_OPT_UTF8,
258#endif
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259 };
260typedef struct {
261 uschar * name; /* option requested during MAIL cmd */
262 int value; /* enum type */
263 BOOL need_value; /* TRUE requires value (name=value pair format)
264 FALSE is a singleton */
265 } env_mail_type_t;
266static env_mail_type_t env_mail_type_list[] = {
267 { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE },
268 { US"BODY", ENV_MAIL_OPT_BODY, TRUE },
269 { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE },
8ccd00b1 270#ifndef DISABLE_PRDR
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271 { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE },
272#endif
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273 { US"RET", ENV_MAIL_OPT_RET, TRUE },
274 { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE },
8c5d388a 275#ifdef SUPPORT_I18N
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276 { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */
277#endif
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278 /* keep this the last entry */
279 { US"NULL", ENV_MAIL_OPT_NULL, FALSE },
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280 };
281
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282/* When reading SMTP from a remote host, we have to use our own versions of the
283C input-reading functions, in order to be able to flush the SMTP output only
284when about to read more data from the socket. This is the only way to get
285optimal performance when the client is using pipelining. Flushing for every
286command causes a separate packet and reply packet each time; saving all the
287responses up (when pipelining) combines them into one packet and one response.
288
289For simplicity, these functions are used for *all* SMTP input, not only when
290receiving over a socket. However, after setting up a secure socket (SSL), input
291is read via the OpenSSL library, and another set of functions is used instead
292(see tls.c).
293
294These functions are set in the receive_getc etc. variables and called with the
295same interface as the C functions. However, since there can only ever be
296one incoming SMTP call, we just use a single buffer and flags. There is no need
297to implement a complicated private FILE-like structure.*/
298
299static uschar *smtp_inbuffer;
300static uschar *smtp_inptr;
301static uschar *smtp_inend;
302static int smtp_had_eof;
303static int smtp_had_error;
304
305
7e3ce68e 306/* forward declarations */
bd8fbe36 307static int smtp_read_command(BOOL check_sync, unsigned buffer_lim);
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308static int synprot_error(int type, int code, uschar *data, uschar *errmess);
309static void smtp_quit_handler(uschar **, uschar **);
310static void smtp_rset_handler(void);
311
059ec3d9 312/*************************************************
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313* Recheck synchronization *
314*************************************************/
315
316/* Synchronization checks can never be perfect because a packet may be on its
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317way but not arrived when the check is done. Normally, the checks happen when
318commands are read: Exim ensures that there is no more input in the input buffer.
319In normal cases, the response to the command will be fast, and there is no
320further check.
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321
322However, for some commands an ACL is run, and that can include delays. In those
323cases, it is useful to do another check on the input just before sending the
324response. This also applies at the start of a connection. This function does
325that check by means of the select() function, as long as the facility is not
326disabled or inappropriate. A failure of select() is ignored.
327
328When there is unwanted input, we read it so that it appears in the log of the
329error.
330
331Arguments: none
332Returns: TRUE if all is well; FALSE if there is input pending
333*/
334
335static BOOL
925ac8e4 336wouldblock_reading(void)
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337{
338int fd, rc;
339fd_set fds;
340struct timeval tzero;
341
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342if (tls_in.active >= 0)
343 return !tls_could_read();
f4630439 344
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345if (smtp_inptr < smtp_inend)
346 return FALSE;
347
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348fd = fileno(smtp_in);
349FD_ZERO(&fds);
350FD_SET(fd, &fds);
351tzero.tv_sec = 0;
352tzero.tv_usec = 0;
353rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
354
355if (rc <= 0) return TRUE; /* Not ready to read */
bd8fbe36 356rc = smtp_getc(GETC_BUFFER_UNLIMITED);
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357if (rc < 0) return TRUE; /* End of file or error */
358
359smtp_ungetc(rc);
360rc = smtp_inend - smtp_inptr;
361if (rc > 150) rc = 150;
362smtp_inptr[rc] = 0;
363return FALSE;
364}
365
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366static BOOL
367check_sync(void)
368{
369if (!smtp_enforce_sync || sender_host_address == NULL || sender_host_notsocket)
370 return TRUE;
371
372return wouldblock_reading();
373}
374
375
376/* If there's input waiting (and we're doing pipelineing) then we can pipeline
377a reponse with the one following. */
378
379static BOOL
380pipeline_response(void)
381{
382if ( !smtp_enforce_sync || !sender_host_address
383 || sender_host_notsocket || !pipelining_advertised)
384 return FALSE;
385
386return !wouldblock_reading();
387}
388
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389
390
391/*************************************************
392* Log incomplete transactions *
393*************************************************/
394
395/* This function is called after a transaction has been aborted by RSET, QUIT,
396connection drops or other errors. It logs the envelope information received
397so far in order to preserve address verification attempts.
398
399Argument: string to indicate what aborted the transaction
400Returns: nothing
401*/
402
403static void
404incomplete_transaction_log(uschar *what)
405{
406if (sender_address == NULL || /* No transaction in progress */
407 !LOGGING(smtp_incomplete_transaction))
408 return;
409
410/* Build list of recipients for logging */
411
412if (recipients_count > 0)
413 {
414 int i;
415 raw_recipients = store_get(recipients_count * sizeof(uschar *));
416 for (i = 0; i < recipients_count; i++)
417 raw_recipients[i] = recipients_list[i].address;
418 raw_recipients_count = recipients_count;
419 }
420
421log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
422 "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
423}
424
425
426
427
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428/* Refill the buffer, and notify DKIM verification code.
429Return false for error or EOF.
430*/
431
432static BOOL
433smtp_refill(unsigned lim)
434{
435int rc, save_errno;
436if (!smtp_out) return FALSE;
437fflush(smtp_out);
438if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
439
440/* Limit amount read, so non-message data is not fed to DKIM */
441
442rc = read(fileno(smtp_in), smtp_inbuffer, MIN(IN_BUFFER_SIZE, lim));
443save_errno = errno;
444alarm(0);
445if (rc <= 0)
446 {
447 /* Must put the error text in fixed store, because this might be during
448 header reading, where it releases unused store above the header. */
449 if (rc < 0)
450 {
451 smtp_had_error = save_errno;
452 smtp_read_error = string_copy_malloc(
453 string_sprintf(" (error: %s)", strerror(save_errno)));
454 }
455 else smtp_had_eof = 1;
456 return FALSE;
457 }
458#ifndef DISABLE_DKIM
459dkim_exim_verify_feed(smtp_inbuffer, rc);
460#endif
461smtp_inend = smtp_inbuffer + rc;
462smtp_inptr = smtp_inbuffer;
463return TRUE;
464}
465
f4630439 466/*************************************************
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467* SMTP version of getc() *
468*************************************************/
469
470/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
471it flushes the output, and refills the buffer, with a timeout. The signal
472handler is set appropriately by the calling function. This function is not used
4c04137d 473after a connection has negotiated itself into an TLS/SSL state.
059ec3d9 474
bd8fbe36 475Arguments: lim Maximum amount to read/buffer
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476Returns: the next character or EOF
477*/
478
479int
bd8fbe36 480smtp_getc(unsigned lim)
059ec3d9
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481{
482if (smtp_inptr >= smtp_inend)
0d81dabc 483 if (!smtp_refill(lim))
059ec3d9 484 return EOF;
059ec3d9
PH
485return *smtp_inptr++;
486}
487
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JH
488uschar *
489smtp_getbuf(unsigned * len)
490{
491unsigned size;
492uschar * buf;
493
494if (smtp_inptr >= smtp_inend)
495 if (!smtp_refill(*len))
496 { *len = 0; return NULL; }
497
498if ((size = smtp_inend - smtp_inptr) > *len) size = *len;
499buf = smtp_inptr;
500smtp_inptr += size;
501*len = size;
502return buf;
503}
504
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505void
506smtp_get_cache(void)
507{
9960d1e5 508#ifndef DISABLE_DKIM
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509int n = smtp_inend - smtp_inptr;
510if (n > 0)
511 dkim_exim_verify_feed(smtp_inptr, n);
584e96c6 512#endif
9960d1e5 513}
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514
515
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516/* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the
517previous BDAT chunk and getting new ones when we run out. Uses the
518underlying smtp_getc or tls_getc both for that and for getting the
519(buffered) data byte. EOD signals (an expected) no further data.
520ERR signals a protocol error, and EOF a closed input stream.
521
522Called from read_bdat_smtp() in receive.c for the message body, but also
523by the headers read loop in receive_msg(); manipulates chunking_state
524to handle the BDAT command/response.
525Placed here due to the correlation with the above smtp_getc(), which it wraps,
526and also by the need to do smtp command/response handling.
527
bd8fbe36 528Arguments: lim (ignored)
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529Returns: the next character or ERR, EOD or EOF
530*/
531
532int
bd8fbe36 533bdat_getc(unsigned lim)
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534{
535uschar * user_msg = NULL;
536uschar * log_msg;
537
538for(;;)
539 {
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540#ifndef DISABLE_DKIM
541 BOOL dkim_save;
542#endif
543
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544 if (chunking_data_left > 0)
545 return lwr_receive_getc(chunking_data_left--);
7e3ce68e
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546
547 receive_getc = lwr_receive_getc;
0d81dabc 548 receive_getbuf = lwr_receive_getbuf;
7e3ce68e 549 receive_ungetc = lwr_receive_ungetc;
bd8fbe36 550#ifndef DISABLE_DKIM
79de4f37 551 dkim_save = dkim_collect_input;
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JH
552 dkim_collect_input = FALSE;
553#endif
7e3ce68e 554
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555 /* Unless PIPELINING was offered, there should be no next command
556 until after we ack that chunk */
557
558 if (!pipelining_advertised && !check_sync())
559 {
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560 unsigned n = smtp_inend - smtp_inptr;
561 if (n > 32) n = 32;
562
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563 incomplete_transaction_log(US"sync failure");
564 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error "
565 "(next input sent too soon: pipelining was not advertised): "
566 "rejected \"%s\" %s next input=\"%s\"",
567 smtp_cmd_buffer, host_and_ident(TRUE),
40525d07 568 string_printing(string_copyn(smtp_inptr, n)));
f4630439
JH
569 (void) synprot_error(L_smtp_protocol_error, 554, NULL,
570 US"SMTP synchronization error");
571 goto repeat_until_rset;
572 }
573
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574 /* If not the last, ack the received chunk. The last response is delayed
575 until after the data ACL decides on it */
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576
577 if (chunking_state == CHUNKING_LAST)
584e96c6
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578 {
579#ifndef DISABLE_DKIM
e983e85a 580 dkim_exim_verify_feed(NULL, 0); /* notify EOD */
584e96c6 581#endif
7e3ce68e 582 return EOD;
584e96c6 583 }
7e3ce68e 584
925ac8e4 585 smtp_printf("250 %u byte chunk received\r\n", FALSE, chunking_datasize);
bd8fbe36
JH
586 chunking_state = CHUNKING_OFFERED;
587 DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
7e3ce68e
JH
588
589 /* Expect another BDAT cmd from input. RFC 3030 says nothing about
590 QUIT, RSET or NOOP but handling them seems obvious */
591
592next_cmd:
bd8fbe36 593 switch(smtp_read_command(TRUE, 1))
7e3ce68e
JH
594 {
595 default:
596 (void) synprot_error(L_smtp_protocol_error, 503, NULL,
597 US"only BDAT permissible after non-LAST BDAT");
598
599 repeat_until_rset:
bd8fbe36 600 switch(smtp_read_command(TRUE, 1))
7e3ce68e
JH
601 {
602 case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */
603 case EOF_CMD: return EOF;
604 case RSET_CMD: smtp_rset_handler(); return ERR;
605 default: if (synprot_error(L_smtp_protocol_error, 503, NULL,
606 US"only RSET accepted now") > 0)
607 return EOF;
608 goto repeat_until_rset;
609 }
610
611 case QUIT_CMD:
612 smtp_quit_handler(&user_msg, &log_msg);
613 /*FALLTHROUGH*/
614 case EOF_CMD:
615 return EOF;
616
617 case RSET_CMD:
618 smtp_rset_handler();
619 return ERR;
620
621 case NOOP_CMD:
622 HAD(SCH_NOOP);
925ac8e4 623 smtp_printf("250 OK\r\n", FALSE);
7e3ce68e
JH
624 goto next_cmd;
625
626 case BDAT_CMD:
627 {
628 int n;
629
630 if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1)
631 {
632 (void) synprot_error(L_smtp_protocol_error, 501, NULL,
633 US"missing size for BDAT command");
634 return ERR;
635 }
636 chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0
637 ? CHUNKING_LAST : CHUNKING_ACTIVE;
638 chunking_data_left = chunking_datasize;
bd8fbe36
JH
639 DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n",
640 (int)chunking_state, chunking_data_left);
7e3ce68e
JH
641
642 if (chunking_datasize == 0)
643 if (chunking_state == CHUNKING_LAST)
644 return EOD;
645 else
646 {
647 (void) synprot_error(L_smtp_protocol_error, 504, NULL,
648 US"zero size for BDAT command");
649 goto repeat_until_rset;
650 }
651
652 receive_getc = bdat_getc;
0d81dabc 653 receive_getbuf = bdat_getbuf;
7e3ce68e 654 receive_ungetc = bdat_ungetc;
bd8fbe36 655#ifndef DISABLE_DKIM
79de4f37 656 dkim_collect_input = dkim_save;
bd8fbe36 657#endif
7e3ce68e
JH
658 break; /* to top of main loop */
659 }
660 }
661 }
662}
663
0d81dabc
JH
664uschar *
665bdat_getbuf(unsigned * len)
666{
667uschar * buf;
668
669if (chunking_data_left <= 0)
670 { *len = 0; return NULL; }
671
672if (*len > chunking_data_left) *len = chunking_data_left;
673buf = lwr_receive_getbuf(len); /* Either smtp_getbuf or tls_getbuf */
674chunking_data_left -= *len;
675return buf;
676}
677
1ebe15c3 678void
45bd315d
JH
679bdat_flush_data(void)
680{
0d81dabc
JH
681unsigned n = chunking_data_left;
682(void) bdat_getbuf(&n);
45bd315d
JH
683
684receive_getc = lwr_receive_getc;
0d81dabc 685receive_getbuf = lwr_receive_getbuf;
45bd315d
JH
686receive_ungetc = lwr_receive_ungetc;
687
688if (chunking_state != CHUNKING_LAST)
bd8fbe36 689 {
45bd315d 690 chunking_state = CHUNKING_OFFERED;
bd8fbe36
JH
691 DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
692 }
45bd315d
JH
693}
694
7e3ce68e
JH
695
696
697
059ec3d9
PH
698/*************************************************
699* SMTP version of ungetc() *
700*************************************************/
701
702/* Puts a character back in the input buffer. Only ever
703called once.
704
705Arguments:
706 ch the character
707
708Returns: the character
709*/
710
711int
712smtp_ungetc(int ch)
713{
7e3ce68e 714*--smtp_inptr = ch;
059ec3d9
PH
715return ch;
716}
717
718
7e3ce68e
JH
719int
720bdat_ungetc(int ch)
721{
722chunking_data_left++;
723return lwr_receive_ungetc(ch);
724}
725
059ec3d9
PH
726
727
728/*************************************************
729* SMTP version of feof() *
730*************************************************/
731
732/* Tests for a previous EOF
733
734Arguments: none
735Returns: non-zero if the eof flag is set
736*/
737
738int
739smtp_feof(void)
740{
741return smtp_had_eof;
742}
743
744
745
746
747/*************************************************
748* SMTP version of ferror() *
749*************************************************/
750
751/* Tests for a previous read error, and returns with errno
752restored to what it was when the error was detected.
753
754Arguments: none
755Returns: non-zero if the error flag is set
756*/
757
758int
759smtp_ferror(void)
760{
761errno = smtp_had_error;
762return smtp_had_error;
763}
764
765
766
58eb016e
PH
767/*************************************************
768* Test for characters in the SMTP buffer *
769*************************************************/
770
771/* Used at the end of a message
772
773Arguments: none
774Returns: TRUE/FALSE
775*/
776
777BOOL
778smtp_buffered(void)
779{
780return smtp_inptr < smtp_inend;
781}
782
783
059ec3d9
PH
784
785/*************************************************
786* Write formatted string to SMTP channel *
787*************************************************/
788
789/* This is a separate function so that we don't have to repeat everything for
790TLS support or debugging. It is global so that the daemon and the
791authentication functions can use it. It does not return any error indication,
792because major problems such as dropped connections won't show up till an output
793flush for non-TLS connections. The smtp_fflush() function is available for
794checking that: for convenience, TLS output errors are remembered here so that
795they are also picked up later by smtp_fflush().
796
797Arguments:
798 format format string
925ac8e4 799 more further data expected
059ec3d9
PH
800 ... optional arguments
801
802Returns: nothing
803*/
804
805void
925ac8e4 806smtp_printf(const char *format, BOOL more, ...)
059ec3d9
PH
807{
808va_list ap;
809
925ac8e4
JH
810va_start(ap, more);
811smtp_vprintf(format, more, ap);
ce552449
NM
812va_end(ap);
813}
814
815/* This is split off so that verify.c:respond_printf() can, in effect, call
816smtp_printf(), bearing in mind that in C a vararg function can't directly
fb08281f 817call another vararg function, only a function which accepts a va_list. */
ce552449
NM
818
819void
925ac8e4 820smtp_vprintf(const char *format, BOOL more, va_list ap)
ce552449 821{
fb08281f
DW
822BOOL yield;
823
824yield = string_vformat(big_buffer, big_buffer_size, format, ap);
ce552449 825
059ec3d9
PH
826DEBUG(D_receive)
827 {
fb08281f
DW
828 void *reset_point = store_get(0);
829 uschar *msg_copy, *cr, *end;
830 msg_copy = string_copy(big_buffer);
831 end = msg_copy + Ustrlen(msg_copy);
832 while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
833 memmove(cr, cr + 1, (end--) - cr);
834 debug_printf("SMTP>> %s", msg_copy);
835 store_reset(reset_point);
059ec3d9
PH
836 }
837
fb08281f 838if (!yield)
2679d413
PH
839 {
840 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
841 smtp_closedown(US"Unexpected error");
842 exim_exit(EXIT_FAILURE);
843 }
2679d413
PH
844
845/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
846have had the same. Note: this code is also present in smtp_respond(). It would
847be tidier to have it only in one place, but when it was added, it was easier to
848do it that way, so as not to have to mess with the code for the RCPT command,
849which sometimes uses smtp_printf() and sometimes smtp_respond(). */
850
851if (rcpt_in_progress)
852 {
853 if (rcpt_smtp_response == NULL)
854 rcpt_smtp_response = string_copy(big_buffer);
855 else if (rcpt_smtp_response_same &&
856 Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
857 rcpt_smtp_response_same = FALSE;
858 rcpt_in_progress = FALSE;
859 }
059ec3d9 860
2679d413 861/* Now write the string */
059ec3d9
PH
862
863#ifdef SUPPORT_TLS
817d9f57 864if (tls_in.active >= 0)
059ec3d9 865 {
925ac8e4 866 if (tls_write(TRUE, big_buffer, Ustrlen(big_buffer), more) < 0)
817d9f57 867 smtp_write_error = -1;
059ec3d9
PH
868 }
869else
870#endif
871
2679d413 872if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1;
059ec3d9
PH
873}
874
875
876
877/*************************************************
878* Flush SMTP out and check for error *
879*************************************************/
880
881/* This function isn't currently used within Exim (it detects errors when it
882tries to read the next SMTP input), but is available for use in local_scan().
883For non-TLS connections, it flushes the output and checks for errors. For
884TLS-connections, it checks for a previously-detected TLS write error.
885
886Arguments: none
887Returns: 0 for no error; -1 after an error
888*/
889
890int
891smtp_fflush(void)
892{
817d9f57 893if (tls_in.active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
059ec3d9
PH
894return smtp_write_error;
895}
896
897
898
899/*************************************************
900* SMTP command read timeout *
901*************************************************/
902
903/* Signal handler for timing out incoming SMTP commands. This attempts to
904finish off tidily.
905
906Argument: signal number (SIGALRM)
907Returns: nothing
908*/
909
910static void
911command_timeout_handler(int sig)
912{
913sig = sig; /* Keep picky compilers happy */
914log_write(L_lost_incoming_connection,
915 LOG_MAIN, "SMTP command timeout on%s connection from %s",
817d9f57 916 (tls_in.active >= 0)? " TLS" : "",
059ec3d9
PH
917 host_and_ident(FALSE));
918if (smtp_batched_input)
919 moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
8f128379
PH
920smtp_notquit_exit(US"command-timeout", US"421",
921 US"%s: SMTP command timeout - closing connection", smtp_active_hostname);
059ec3d9
PH
922exim_exit(EXIT_FAILURE);
923}
924
925
926
927/*************************************************
928* SIGTERM received *
929*************************************************/
930
931/* Signal handler for handling SIGTERM. Again, try to finish tidily.
932
933Argument: signal number (SIGTERM)
934Returns: nothing
935*/
936
937static void
938command_sigterm_handler(int sig)
939{
940sig = sig; /* Keep picky compilers happy */
941log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
942if (smtp_batched_input)
943 moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
8f128379
PH
944smtp_notquit_exit(US"signal-exit", US"421",
945 US"%s: Service not available - closing connection", smtp_active_hostname);
059ec3d9
PH
946exim_exit(EXIT_FAILURE);
947}
948
949
950
a14e5636 951
cee5f132 952#ifdef SUPPORT_PROXY
a3c86431 953/*************************************************
a3bddaa8
TL
954* Restore socket timeout to previous value *
955*************************************************/
956/* If the previous value was successfully retrieved, restore
957it before returning control to the non-proxy routines
958
959Arguments: fd - File descriptor for input
960 get_ok - Successfully retrieved previous values
961 tvtmp - Time struct with previous values
962 vslen - Length of time struct
963Returns: none
964*/
965static void
f267271d 966restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen)
a3bddaa8
TL
967{
968if (get_ok == 0)
f267271d 969 (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen);
a3bddaa8
TL
970}
971
972/*************************************************
a3c86431
TL
973* Check if host is required proxy host *
974*************************************************/
975/* The function determines if inbound host will be a regular smtp host
1811cb4c
JH
976or if it is configured that it must use Proxy Protocol. A local
977connection cannot.
a3c86431
TL
978
979Arguments: none
980Returns: bool
981*/
982
983static BOOL
984check_proxy_protocol_host()
985{
986int rc;
a3c86431 987
1811cb4c
JH
988if ( sender_host_address
989 && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL,
990 sender_host_address, NULL)) == OK)
a3c86431
TL
991 {
992 DEBUG(D_receive)
993 debug_printf("Detected proxy protocol configured host\n");
994 proxy_session = TRUE;
995 }
996return proxy_session;
997}
998
999
1000/*************************************************
3f251b3c
PP
1001* Read data until newline or end of buffer *
1002*************************************************/
1003/* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't
1004read an entire buffer and assume there will be nothing past a proxy protocol
1005header. Our approach normally is to use stdio, but again that relies upon
1006"STARTTLS\r\n" and a server response before the client starts TLS handshake, or
1007reading _nothing_ before client TLS handshake. So we don't want to use the
1008usual buffering reads which may read enough to block TLS starting.
1009
1010So unfortunately we're down to "read one byte at a time, with a syscall each,
1011and expect a little overhead", for all proxy-opened connections which are v1,
1012just to handle the TLS-on-connect case. Since SSL functions wrap the
1013underlying fd, we can't assume that we can feed them any already-read content.
1014
1015We need to know where to read to, the max capacity, and we'll read until we
1016get a CR and one more character. Let the caller scream if it's CR+!LF.
1017
1018Return the amount read.
1019*/
1020
1021static int
da88acae 1022swallow_until_crlf(int fd, uschar *base, int already, int capacity)
3f251b3c 1023{
2c0f3ea1
JH
1024uschar *to = base + already;
1025uschar *cr;
1026int have = 0;
1027int ret;
1028int last = 0;
1029
1030/* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read
1031up through the \r; for the _normal_ case, we haven't yet seen the \r. */
da88acae 1032
2c0f3ea1
JH
1033cr = memchr(base, '\r', already);
1034if (cr != NULL)
1035 {
1036 if ((cr - base) < already - 1)
da88acae 1037 {
2c0f3ea1
JH
1038 /* \r and presumed \n already within what we have; probably not
1039 actually proxy protocol, but abort cleanly. */
1040 return 0;
da88acae 1041 }
2c0f3ea1
JH
1042 /* \r is last character read, just need one more. */
1043 last = 1;
1044 }
1045
1046while (capacity > 0)
1047 {
1048 do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR);
1049 if (ret == -1)
1050 return -1;
1051 have++;
1052 if (last)
1053 return have;
1054 if (*to == '\r')
1055 last = 1;
1056 capacity--;
1057 to++;
1058 }
1059
1060/* reached end without having room for a final newline, abort */
1061errno = EOVERFLOW;
1062return -1;
3f251b3c
PP
1063}
1064
1065/*************************************************
a3c86431
TL
1066* Setup host for proxy protocol *
1067*************************************************/
1068/* The function configures the connection based on a header from the
1069inbound host to use Proxy Protocol. The specification is very exact
1070so exit with an error if do not find the exact required pieces. This
1071includes an incorrect number of spaces separating args.
1072
1073Arguments: none
f267271d 1074Returns: Boolean success
a3c86431
TL
1075*/
1076
1811cb4c 1077static void
a3c86431
TL
1078setup_proxy_protocol_host()
1079{
1080union {
1081 struct {
1082 uschar line[108];
1083 } v1;
1084 struct {
1085 uschar sig[12];
36719342
TL
1086 uint8_t ver_cmd;
1087 uint8_t fam;
1088 uint16_t len;
a3c86431
TL
1089 union {
1090 struct { /* TCP/UDP over IPv4, len = 12 */
1091 uint32_t src_addr;
1092 uint32_t dst_addr;
1093 uint16_t src_port;
1094 uint16_t dst_port;
1095 } ip4;
1096 struct { /* TCP/UDP over IPv6, len = 36 */
1097 uint8_t src_addr[16];
1098 uint8_t dst_addr[16];
1099 uint16_t src_port;
1100 uint16_t dst_port;
1101 } ip6;
1102 struct { /* AF_UNIX sockets, len = 216 */
1103 uschar src_addr[108];
1104 uschar dst_addr[108];
1105 } unx;
1106 } addr;
1107 } v2;
1108} hdr;
1109
eb57651e
TL
1110/* Temp variables used in PPv2 address:port parsing */
1111uint16_t tmpport;
1112char tmpip[INET_ADDRSTRLEN];
1113struct sockaddr_in tmpaddr;
1114char tmpip6[INET6_ADDRSTRLEN];
1115struct sockaddr_in6 tmpaddr6;
1116
da88acae
PP
1117/* We can't read "all data until end" because while SMTP is
1118server-speaks-first, the TLS handshake is client-speaks-first, so for
1119TLS-on-connect ports the proxy protocol header will usually be immediately
1120followed by a TLS handshake, and with N TLS libraries, we can't reliably
1121reinject data for reading by those. So instead we first read "enough to be
1122safely read within the header, and figure out how much more to read".
1123For v1 we will later read to the end-of-line, for v2 we will read based upon
1124the stated length.
1125
1126The v2 sig is 12 octets, and another 4 gets us the length, so we know how much
1127data is needed total. For v1, where the line looks like:
1128PROXY TCPn L3src L3dest SrcPort DestPort \r\n
1129
1130However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets.
1131We seem to support that. So, if we read 14 octets then we can tell if we're
1132v2 or v1. If we're v1, we can continue reading as normal.
1133
1134If we're v2, we can't slurp up the entire header. We need the length in the
113515th & 16th octets, then to read everything after that.
1136
1137So to safely handle v1 and v2, with client-sent-first supported correctly,
1138we have to do a minimum of 3 read calls, not 1. Eww.
1139*/
1140
1141#define PROXY_INITIAL_READ 14
1142#define PROXY_V2_HEADER_SIZE 16
1143#if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE
1144# error Code bug in sizes of data to read for proxy usage
1145#endif
1146
eb57651e 1147int get_ok = 0;
f267271d
JH
1148int size, ret;
1149int fd = fileno(smtp_in);
36719342 1150const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
9e7e0f6a 1151uschar * iptype; /* To display debug info */
a3c86431 1152struct timeval tv;
a3bddaa8 1153struct timeval tvtmp;
f267271d 1154socklen_t vslen = sizeof(struct timeval);
1811cb4c 1155BOOL yield = FALSE;
a3c86431 1156
a3bddaa8 1157/* Save current socket timeout values */
f267271d 1158get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen);
a3bddaa8 1159
a3c86431
TL
1160/* Proxy Protocol host must send header within a short time
1161(default 3 seconds) or it's considered invalid */
1162tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC;
1163tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC;
f267271d 1164if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0)
1811cb4c 1165 goto bad;
a3bddaa8 1166
a3c86431
TL
1167do
1168 {
eb57651e 1169 /* The inbound host was declared to be a Proxy Protocol host, so
2c0f3ea1
JH
1170 don't do a PEEK into the data, actually slurp up enough to be
1171 "safe". Can't take it all because TLS-on-connect clients follow
1172 immediately with TLS handshake. */
3f251b3c 1173 ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0);
a3c86431
TL
1174 }
1175 while (ret == -1 && errno == EINTR);
1176
1177if (ret == -1)
f267271d 1178 goto proxyfail;
a3c86431 1179
da88acae
PP
1180/* For v2, handle reading the length, and then the rest. */
1181if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0))
a3c86431 1182 {
da88acae
PP
1183 int retmore;
1184 uint8_t ver;
1185
1186 /* First get the length fields. */
1187 do
1188 {
1189 retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0);
1190 } while (retmore == -1 && errno == EINTR);
1191 if (retmore == -1)
3f251b3c 1192 goto proxyfail;
da88acae 1193 ret += retmore;
3f251b3c
PP
1194
1195 ver = (hdr.v2.ver_cmd & 0xf0) >> 4;
36719342
TL
1196
1197 /* May 2014: haproxy combined the version and command into one byte to
2c0f3ea1
JH
1198 allow two full bytes for the length field in order to proxy SSL
1199 connections. SSL Proxy is not supported in this version of Exim, but
1200 must still separate values here. */
36719342
TL
1201
1202 if (ver != 0x02)
1203 {
1204 DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver);
1205 goto proxyfail;
1206 }
da88acae 1207
36719342 1208 /* The v2 header will always be 16 bytes per the spec. */
5d036699 1209 size = 16 + ntohs(hdr.v2.len);
da88acae
PP
1210 DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n",
1211 size, (int)sizeof(hdr));
1212
1213 /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total
1214 amount that we need. Double-check that the size is not unreasonable, then
1215 get the rest. */
1216 if (size > sizeof(hdr))
a3c86431 1217 {
da88acae 1218 DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n");
a3c86431
TL
1219 goto proxyfail;
1220 }
da88acae
PP
1221
1222 do
1223 {
1224 do
1225 {
1226 retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0);
1227 } while (retmore == -1 && errno == EINTR);
1228 if (retmore == -1)
1229 goto proxyfail;
1230 ret += retmore;
1231 DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size);
1232 } while (ret < size);
1233
1234 } /* end scope for getting rest of data for v2 */
1235
1236/* At this point: if PROXYv2, we've read the exact size required for all data;
1237if PROXYv1 then we've read "less than required for any valid line" and should
1238read the rest". */
1239
1240if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0)
1241 {
1242 uint8_t cmd = (hdr.v2.ver_cmd & 0x0f);
1243
36719342 1244 switch (cmd)
a3c86431
TL
1245 {
1246 case 0x01: /* PROXY command */
1247 switch (hdr.v2.fam)
1248 {
eb57651e
TL
1249 case 0x11: /* TCPv4 address type */
1250 iptype = US"IPv4";
1251 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr;
5d036699
JH
1252 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1253 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1254 {
1255 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1256 goto proxyfail;
eb57651e 1257 }
e6d2a989 1258 proxy_local_address = sender_host_address;
eb57651e
TL
1259 sender_host_address = string_copy(US tmpip);
1260 tmpport = ntohs(hdr.v2.addr.ip4.src_port);
e6d2a989 1261 proxy_local_port = sender_host_port;
eb57651e
TL
1262 sender_host_port = tmpport;
1263 /* Save dest ip/port */
1264 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr;
5d036699
JH
1265 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1266 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1267 {
1268 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1269 goto proxyfail;
eb57651e 1270 }
7a2fa0bc 1271 proxy_external_address = string_copy(US tmpip);
eb57651e 1272 tmpport = ntohs(hdr.v2.addr.ip4.dst_port);
7a2fa0bc 1273 proxy_external_port = tmpport;
a3c86431 1274 goto done;
eb57651e
TL
1275 case 0x21: /* TCPv6 address type */
1276 iptype = US"IPv6";
1277 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16);
5d036699
JH
1278 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1279 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1280 {
1281 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1282 goto proxyfail;
eb57651e 1283 }
e6d2a989 1284 proxy_local_address = sender_host_address;
eb57651e
TL
1285 sender_host_address = string_copy(US tmpip6);
1286 tmpport = ntohs(hdr.v2.addr.ip6.src_port);
e6d2a989 1287 proxy_local_port = sender_host_port;
eb57651e
TL
1288 sender_host_port = tmpport;
1289 /* Save dest ip/port */
1290 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16);
5d036699
JH
1291 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1292 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1293 {
1294 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1295 goto proxyfail;
eb57651e 1296 }
7a2fa0bc 1297 proxy_external_address = string_copy(US tmpip6);
eb57651e 1298 tmpport = ntohs(hdr.v2.addr.ip6.dst_port);
7a2fa0bc 1299 proxy_external_port = tmpport;
a3c86431 1300 goto done;
eb57651e
TL
1301 default:
1302 DEBUG(D_receive)
1303 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
1304 hdr.v2.fam);
1305 goto proxyfail;
a3c86431
TL
1306 }
1307 /* Unsupported protocol, keep local connection address */
1308 break;
1309 case 0x00: /* LOCAL command */
1310 /* Keep local connection address for LOCAL */
9e7e0f6a 1311 iptype = US"local";
a3c86431
TL
1312 break;
1313 default:
eb57651e 1314 DEBUG(D_receive)
36719342 1315 debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd);
a3c86431
TL
1316 goto proxyfail;
1317 }
1318 }
5d036699 1319else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0)
a3c86431 1320 {
3f251b3c
PP
1321 uschar *p;
1322 uschar *end;
a3c86431
TL
1323 uschar *sp; /* Utility variables follow */
1324 int tmp_port;
3f251b3c 1325 int r2;
a3c86431
TL
1326 char *endc;
1327
3f251b3c 1328 /* get the rest of the line */
da88acae 1329 r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
3f251b3c
PP
1330 if (r2 == -1)
1331 goto proxyfail;
1332 ret += r2;
1333
1334 p = string_copy(hdr.v1.line);
1335 end = memchr(p, '\r', ret - 1);
1336
da88acae 1337 if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n')
a3c86431
TL
1338 {
1339 DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n");
1340 goto proxyfail;
1341 }
1342 *end = '\0'; /* Terminate the string */
a5d4db40 1343 size = end + 2 - p; /* Skip header + CRLF */
a3c86431 1344 DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n");
3f251b3c 1345 DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size);
a3c86431 1346 /* Step through the string looking for the required fields. Ensure
2c0f3ea1 1347 strict adherence to required formatting, exit for any error. */
a3c86431
TL
1348 p += 5;
1349 if (!isspace(*(p++)))
1350 {
1351 DEBUG(D_receive) debug_printf("Missing space after PROXY command\n");
1352 goto proxyfail;
1353 }
1354 if (!Ustrncmp(p, CCS"TCP4", 4))
1355 iptype = US"IPv4";
1356 else if (!Ustrncmp(p,CCS"TCP6", 4))
1357 iptype = US"IPv6";
1358 else if (!Ustrncmp(p,CCS"UNKNOWN", 7))
1359 {
1360 iptype = US"Unknown";
1361 goto done;
1362 }
1363 else
1364 {
1365 DEBUG(D_receive) debug_printf("Invalid TCP type\n");
1366 goto proxyfail;
1367 }
1368
1369 p += Ustrlen(iptype);
1370 if (!isspace(*(p++)))
1371 {
1372 DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n");
1373 goto proxyfail;
1374 }
1375 /* Find the end of the arg */
1376 if ((sp = Ustrchr(p, ' ')) == NULL)
1377 {
1378 DEBUG(D_receive)
1379 debug_printf("Did not find proxied src %s\n", iptype);
1380 goto proxyfail;
1381 }
1382 *sp = '\0';
5d036699 1383 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1384 {
1385 DEBUG(D_receive)
1386 debug_printf("Proxied src arg is not an %s address\n", iptype);
1387 goto proxyfail;
1388 }
e6d2a989 1389 proxy_local_address = sender_host_address;
a3c86431
TL
1390 sender_host_address = p;
1391 p = sp + 1;
1392 if ((sp = Ustrchr(p, ' ')) == NULL)
1393 {
1394 DEBUG(D_receive)
1395 debug_printf("Did not find proxy dest %s\n", iptype);
1396 goto proxyfail;
1397 }
1398 *sp = '\0';
5d036699 1399 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1400 {
1401 DEBUG(D_receive)
1402 debug_printf("Proxy dest arg is not an %s address\n", iptype);
1403 goto proxyfail;
1404 }
7a2fa0bc 1405 proxy_external_address = p;
a3c86431
TL
1406 p = sp + 1;
1407 if ((sp = Ustrchr(p, ' ')) == NULL)
1408 {
1409 DEBUG(D_receive) debug_printf("Did not find proxied src port\n");
1410 goto proxyfail;
1411 }
1412 *sp = '\0';
5d036699 1413 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1414 if (*endc || tmp_port == 0)
1415 {
1416 DEBUG(D_receive)
1417 debug_printf("Proxied src port '%s' not an integer\n", p);
1418 goto proxyfail;
1419 }
e6d2a989 1420 proxy_local_port = sender_host_port;
a3c86431
TL
1421 sender_host_port = tmp_port;
1422 p = sp + 1;
1423 if ((sp = Ustrchr(p, '\0')) == NULL)
1424 {
1425 DEBUG(D_receive) debug_printf("Did not find proxy dest port\n");
1426 goto proxyfail;
1427 }
5d036699 1428 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1429 if (*endc || tmp_port == 0)
1430 {
1431 DEBUG(D_receive)
1432 debug_printf("Proxy dest port '%s' not an integer\n", p);
1433 goto proxyfail;
1434 }
7a2fa0bc 1435 proxy_external_port = tmp_port;
a3c86431 1436 /* Already checked for /r /n above. Good V1 header received. */
a3c86431
TL
1437 }
1438else
1439 {
1440 /* Wrong protocol */
eb57651e 1441 DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n");
da88acae 1442 (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
a3c86431
TL
1443 goto proxyfail;
1444 }
1445
1811cb4c
JH
1446done:
1447 DEBUG(D_receive)
1448 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype);
1449 yield = proxy_session;
1450
1451/* Don't flush any potential buffer contents. Any input on proxyfail
1452should cause a synchronization failure */
1453
a3c86431 1454proxyfail:
1811cb4c 1455 restore_socket_timeout(fd, get_ok, &tvtmp, vslen);
a3c86431 1456
1811cb4c
JH
1457bad:
1458 if (yield)
1459 {
1460 sender_host_name = NULL;
1461 (void) host_name_lookup();
1462 host_build_sender_fullhost();
1463 }
1464 else
1465 {
1466 proxy_session_failed = TRUE;
1467 DEBUG(D_receive)
1468 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
1469 }
1470
1471return;
a3c86431
TL
1472}
1473#endif
1474
059ec3d9
PH
1475/*************************************************
1476* Read one command line *
1477*************************************************/
1478
1479/* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
1480There are sites that don't do this, and in any case internal SMTP probably
1481should check only for LF. Consequently, we check here for LF only. The line
1482ends up with [CR]LF removed from its end. If we get an overlong line, treat as
3ee512ff
PH
1483an unknown command. The command is read into the global smtp_cmd_buffer so that
1484it is available via $smtp_command.
059ec3d9
PH
1485
1486The character reading routine sets up a timeout for each block actually read
1487from the input (which may contain more than one command). We set up a special
1488signal handler that closes down the session on a timeout. Control does not
1489return when it runs.
1490
1491Arguments:
bd8fbe36
JH
1492 check_sync if TRUE, check synchronization rules if global option is TRUE
1493 buffer_lim maximum to buffer in lower layer
059ec3d9
PH
1494
1495Returns: a code identifying the command (enumerated above)
1496*/
1497
1498static int
bd8fbe36 1499smtp_read_command(BOOL check_sync, unsigned buffer_lim)
059ec3d9
PH
1500{
1501int c;
1502int ptr = 0;
1503smtp_cmd_list *p;
1504BOOL hadnull = FALSE;
1505
1506os_non_restarting_signal(SIGALRM, command_timeout_handler);
1507
bd8fbe36 1508while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF)
059ec3d9 1509 {
bd8fbe36 1510 if (ptr >= SMTP_CMD_BUFFER_SIZE)
059ec3d9
PH
1511 {
1512 os_non_restarting_signal(SIGALRM, sigalrm_handler);
1513 return OTHER_CMD;
1514 }
1515 if (c == 0)
1516 {
1517 hadnull = TRUE;
1518 c = '?';
1519 }
3ee512ff 1520 smtp_cmd_buffer[ptr++] = c;
059ec3d9
PH
1521 }
1522
1523receive_linecount++; /* For BSMTP errors */
1524os_non_restarting_signal(SIGALRM, sigalrm_handler);
1525
1526/* If hit end of file, return pseudo EOF command. Whether we have a
1527part-line already read doesn't matter, since this is an error state. */
1528
1529if (c == EOF) return EOF_CMD;
1530
1531/* Remove any CR and white space at the end of the line, and terminate the
1532string. */
1533
3ee512ff
PH
1534while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
1535smtp_cmd_buffer[ptr] = 0;
059ec3d9 1536
3ee512ff 1537DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
059ec3d9
PH
1538
1539/* NULLs are not allowed in SMTP commands */
1540
1541if (hadnull) return BADCHAR_CMD;
1542
1543/* Scan command list and return identity, having set the data pointer
1544to the start of the actual data characters. Check for SMTP synchronization
1545if required. */
1546
1547for (p = cmd_list; p < cmd_list_end; p++)
1548 {
1811cb4c 1549#ifdef SUPPORT_PROXY
a3c86431 1550 /* Only allow QUIT command if Proxy Protocol parsing failed */
1811cb4c
JH
1551 if (proxy_session && proxy_session_failed && p->cmd != QUIT_CMD)
1552 continue;
1553#endif
2f460950
JH
1554 if ( p->len
1555 && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0
1556 && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */
1557 || smtp_cmd_buffer[p->len] == 0
1558 || smtp_cmd_buffer[p->len] == ' '
1559 ) )
059ec3d9
PH
1560 {
1561 if (smtp_inptr < smtp_inend && /* Outstanding input */
1562 p->cmd < sync_cmd_limit && /* Command should sync */
1563 check_sync && /* Local flag set */
1564 smtp_enforce_sync && /* Global flag set */
1565 sender_host_address != NULL && /* Not local input */
1566 !sender_host_notsocket) /* Really is a socket */
1567 return BADSYN_CMD;
1568
ca86f471
PH
1569 /* The variables $smtp_command and $smtp_command_argument point into the
1570 unmodified input buffer. A copy of the latter is taken for actual
1571 processing, so that it can be chopped up into separate parts if necessary,
1572 for example, when processing a MAIL command options such as SIZE that can
1573 follow the sender address. */
059ec3d9 1574
3ee512ff 1575 smtp_cmd_argument = smtp_cmd_buffer + p->len;
ca86f471
PH
1576 while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
1577 Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
1578 smtp_cmd_data = smtp_data_buffer;
059ec3d9
PH
1579
1580 /* Count non-mail commands from those hosts that are controlled in this
1581 way. The default is all hosts. We don't waste effort checking the list
1582 until we get a non-mail command, but then cache the result to save checking
1583 again. If there's a DEFER while checking the host, assume it's in the list.
1584
1585 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1586 start of each incoming message by fiddling with the value in the table. */
1587
1588 if (!p->is_mail_cmd)
1589 {
1590 if (count_nonmail == TRUE_UNSET) count_nonmail =
1591 verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL;
1592 if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail)
1593 return TOO_MANY_NONMAIL_CMD;
1594 }
1595
ca86f471
PH
1596 /* If there is data for a command that does not expect it, generate the
1597 error here. */
059ec3d9 1598
ca86f471 1599 return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
059ec3d9
PH
1600 }
1601 }
1602
cee5f132 1603#ifdef SUPPORT_PROXY
a3c86431
TL
1604/* Only allow QUIT command if Proxy Protocol parsing failed */
1605if (proxy_session && proxy_session_failed)
1606 return PROXY_FAIL_IGNORE_CMD;
1607#endif
1608
059ec3d9
PH
1609/* Enforce synchronization for unknown commands */
1610
1611if (smtp_inptr < smtp_inend && /* Outstanding input */
1612 check_sync && /* Local flag set */
1613 smtp_enforce_sync && /* Global flag set */
1614 sender_host_address != NULL && /* Not local input */
1615 !sender_host_notsocket) /* Really is a socket */
1616 return BADSYN_CMD;
1617
1618return OTHER_CMD;
1619}
1620
1621
1622
1623/*************************************************
1624* Forced closedown of call *
1625*************************************************/
1626
1627/* This function is called from log.c when Exim is dying because of a serious
1628disaster, and also from some other places. If an incoming non-batched SMTP
1629channel is open, it swallows the rest of the incoming message if in the DATA
1630phase, sends the reply string, and gives an error to all subsequent commands
1631except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1632smtp_in.
1633
8f128379
PH
1634Arguments:
1635 message SMTP reply string to send, excluding the code
1636
059ec3d9
PH
1637Returns: nothing
1638*/
1639
1640void
1641smtp_closedown(uschar *message)
1642{
1643if (smtp_in == NULL || smtp_batched_input) return;
1644receive_swallow_smtp();
925ac8e4 1645smtp_printf("421 %s\r\n", FALSE, message);
059ec3d9 1646
bd8fbe36 1647for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9 1648 {
60d10ce7
JH
1649 case EOF_CMD:
1650 return;
059ec3d9 1651
60d10ce7 1652 case QUIT_CMD:
925ac8e4 1653 smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
60d10ce7
JH
1654 mac_smtp_fflush();
1655 return;
059ec3d9 1656
60d10ce7 1657 case RSET_CMD:
925ac8e4 1658 smtp_printf("250 Reset OK\r\n", FALSE);
60d10ce7 1659 break;
059ec3d9 1660
60d10ce7 1661 default:
925ac8e4 1662 smtp_printf("421 %s\r\n", FALSE, message);
60d10ce7 1663 break;
059ec3d9
PH
1664 }
1665}
1666
1667
1668
1669
1670/*************************************************
1671* Set up connection info for logging *
1672*************************************************/
1673
1674/* This function is called when logging information about an SMTP connection.
1675It sets up appropriate source information, depending on the type of connection.
dac79d3e
PH
1676If sender_fullhost is NULL, we are at a very early stage of the connection;
1677just use the IP address.
059ec3d9
PH
1678
1679Argument: none
1680Returns: a string describing the connection
1681*/
1682
1683uschar *
1684smtp_get_connection_info(void)
1685{
f5d25c2b
JH
1686const uschar * hostname = sender_fullhost
1687 ? sender_fullhost : sender_host_address;
dac79d3e 1688
059ec3d9 1689if (host_checking)
dac79d3e 1690 return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1691
1692if (sender_host_unknown || sender_host_notsocket)
1693 return string_sprintf("SMTP connection from %s", sender_ident);
1694
1695if (is_inetd)
dac79d3e 1696 return string_sprintf("SMTP connection from %s (via inetd)", hostname);
059ec3d9 1697
6c6d6e48 1698if (LOGGING(incoming_interface) && interface_address != NULL)
dac79d3e 1699 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
059ec3d9
PH
1700 interface_address, interface_port);
1701
dac79d3e 1702return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1703}
1704
1705
1706
e45a1c37 1707#ifdef SUPPORT_TLS
887291d2
JH
1708/* Append TLS-related information to a log line
1709
1710Arguments:
1711 s String under construction: allocated string to extend, or NULL
1712 sizep Pointer to current allocation size (update on return), or NULL
1713 ptrp Pointer to index for new entries in string (update on return), or NULL
1714
1715Returns: Allocated string or NULL
1716*/
e45a1c37
JH
1717static uschar *
1718s_tlslog(uschar * s, int * sizep, int * ptrp)
1719{
1720 int size = sizep ? *sizep : 0;
1721 int ptr = ptrp ? *ptrp : 0;
1722
6c6d6e48 1723 if (LOGGING(tls_cipher) && tls_in.cipher != NULL)
e45a1c37 1724 s = string_append(s, &size, &ptr, 2, US" X=", tls_in.cipher);
6c6d6e48 1725 if (LOGGING(tls_certificate_verified) && tls_in.cipher != NULL)
e45a1c37
JH
1726 s = string_append(s, &size, &ptr, 2, US" CV=",
1727 tls_in.certificate_verified? "yes":"no");
6c6d6e48 1728 if (LOGGING(tls_peerdn) && tls_in.peerdn != NULL)
e45a1c37
JH
1729 s = string_append(s, &size, &ptr, 3, US" DN=\"",
1730 string_printing(tls_in.peerdn), US"\"");
6c6d6e48 1731 if (LOGGING(tls_sni) && tls_in.sni != NULL)
e45a1c37
JH
1732 s = string_append(s, &size, &ptr, 3, US" SNI=\"",
1733 string_printing(tls_in.sni), US"\"");
1734
67d81c10
JH
1735 if (s)
1736 {
1737 s[ptr] = '\0';
1738 if (sizep) *sizep = size;
1739 if (ptrp) *ptrp = ptr;
1740 }
e45a1c37
JH
1741 return s;
1742}
1743#endif
1744
059ec3d9 1745/*************************************************
b4ed4da0
PH
1746* Log lack of MAIL if so configured *
1747*************************************************/
1748
1749/* This function is called when an SMTP session ends. If the log selector
1750smtp_no_mail is set, write a log line giving some details of what has happened
1751in the SMTP session.
1752
1753Arguments: none
1754Returns: nothing
1755*/
1756
1757void
1758smtp_log_no_mail(void)
1759{
1760int size, ptr, i;
1761uschar *s, *sep;
1762
6c6d6e48 1763if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail))
b4ed4da0
PH
1764 return;
1765
1766s = NULL;
1767size = ptr = 0;
1768
1769if (sender_host_authenticated != NULL)
1770 {
1771 s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated);
1772 if (authenticated_id != NULL)
1773 s = string_append(s, &size, &ptr, 2, US":", authenticated_id);
1774 }
1775
1776#ifdef SUPPORT_TLS
e45a1c37 1777s = s_tlslog(s, &size, &ptr);
3f0945ff 1778#endif
b4ed4da0
PH
1779
1780sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)?
1781 US" C=..." : US" C=";
1782for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
1783 {
1784 if (smtp_connection_had[i] != SCH_NONE)
1785 {
1786 s = string_append(s, &size, &ptr, 2, sep,
1787 smtp_names[smtp_connection_had[i]]);
1788 sep = US",";
1789 }
1790 }
1791
1792for (i = 0; i < smtp_ch_index; i++)
1793 {
1794 s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]);
1795 sep = US",";
1796 }
1797
a09f2942 1798if (s) s[ptr] = 0; else s = US"";
b4ed4da0
PH
1799log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s",
1800 host_and_ident(FALSE),
19050083
JH
1801 readconf_printtime( (int) ((long)time(NULL) - (long)smtp_connection_start)),
1802 s);
b4ed4da0
PH
1803}
1804
1805
a09f2942
JH
1806/* Return list of recent smtp commands */
1807
1808uschar *
1809smtp_cmd_hist(void)
1810{
1811uschar * list = NULL;
1812int size = 0, len = 0, i;
1813
1814for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
1815 if (smtp_connection_had[i] != SCH_NONE)
1816 list = string_append_listele(list, &size, &len, ',',
1817 smtp_names[smtp_connection_had[i]]);
1818for (i = 0; i < smtp_ch_index; i++)
1819 list = string_append_listele(list, &size, &len, ',',
1820 smtp_names[smtp_connection_had[i]]);
1821return list ? list : US"";
1822}
1823
1824
1825
b4ed4da0
PH
1826
1827/*************************************************
059ec3d9
PH
1828* Check HELO line and set sender_helo_name *
1829*************************************************/
1830
1831/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1832the domain name of the sending host, or an ip literal in square brackets. The
4c04137d 1833argument is placed in sender_helo_name, which is in malloc store, because it
059ec3d9
PH
1834must persist over multiple incoming messages. If helo_accept_junk is set, this
1835host is permitted to send any old junk (needed for some broken hosts).
1836Otherwise, helo_allow_chars can be used for rogue characters in general
1837(typically people want to let in underscores).
1838
1839Argument:
1840 s the data portion of the line (already past any white space)
1841
1842Returns: TRUE or FALSE
1843*/
1844
1845static BOOL
1846check_helo(uschar *s)
1847{
1848uschar *start = s;
1849uschar *end = s + Ustrlen(s);
1850BOOL yield = helo_accept_junk;
1851
1852/* Discard any previous helo name */
1853
1854if (sender_helo_name != NULL)
1855 {
1856 store_free(sender_helo_name);
1857 sender_helo_name = NULL;
1858 }
1859
1860/* Skip tests if junk is permitted. */
1861
1862if (!yield)
1863 {
1864 /* Allow the new standard form for IPv6 address literals, namely,
1865 [IPv6:....], and because someone is bound to use it, allow an equivalent
1866 IPv4 form. Allow plain addresses as well. */
1867
1868 if (*s == '[')
1869 {
1870 if (end[-1] == ']')
1871 {
1872 end[-1] = 0;
1873 if (strncmpic(s, US"[IPv6:", 6) == 0)
1874 yield = (string_is_ip_address(s+6, NULL) == 6);
1875 else if (strncmpic(s, US"[IPv4:", 6) == 0)
1876 yield = (string_is_ip_address(s+6, NULL) == 4);
1877 else
1878 yield = (string_is_ip_address(s+1, NULL) != 0);
1879 end[-1] = ']';
1880 }
1881 }
1882
1883 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1884 that have been configured (usually underscore - sigh). */
1885
1886 else if (*s != 0)
1887 {
1888 yield = TRUE;
1889 while (*s != 0)
1890 {
1891 if (!isalnum(*s) && *s != '.' && *s != '-' &&
1892 Ustrchr(helo_allow_chars, *s) == NULL)
1893 {
1894 yield = FALSE;
1895 break;
1896 }
1897 s++;
1898 }
1899 }
1900 }
1901
1902/* Save argument if OK */
1903
1904if (yield) sender_helo_name = string_copy_malloc(start);
1905return yield;
1906}
1907
1908
1909
1910
1911
1912/*************************************************
1913* Extract SMTP command option *
1914*************************************************/
1915
ca86f471 1916/* This function picks the next option setting off the end of smtp_cmd_data. It
059ec3d9
PH
1917is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1918things that can appear there.
1919
1920Arguments:
1921 name point this at the name
1922 value point this at the data string
1923
1924Returns: TRUE if found an option
1925*/
1926
1927static BOOL
1928extract_option(uschar **name, uschar **value)
1929{
1930uschar *n;
ca86f471 1931uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
059ec3d9
PH
1932while (isspace(*v)) v--;
1933v[1] = 0;
d7a2c833
JH
1934while (v > smtp_cmd_data && *v != '=' && !isspace(*v))
1935 {
1936 /* Take care to not stop at a space embedded in a quoted local-part */
1937
1938 if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1);
1939 v--;
1940 }
059ec3d9
PH
1941
1942n = v;
fd98a5c6
JH
1943if (*v == '=')
1944{
1945 while(isalpha(n[-1])) n--;
1946 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
1947 if (!isspace(n[-1])) return FALSE;
1948 n[-1] = 0;
1949}
1950else
1951{
1952 n++;
1953 if (v == smtp_cmd_data) return FALSE;
1954}
059ec3d9 1955*v++ = 0;
fd98a5c6 1956*name = n;
059ec3d9
PH
1957*value = v;
1958return TRUE;
1959}
1960
1961
1962
1963
1964
059ec3d9
PH
1965/*************************************************
1966* Reset for new message *
1967*************************************************/
1968
1969/* This function is called whenever the SMTP session is reset from
1970within either of the setup functions.
1971
1972Argument: the stacking pool storage reset point
1973Returns: nothing
1974*/
1975
1976static void
1977smtp_reset(void *reset_point)
1978{
059ec3d9
PH
1979recipients_list = NULL;
1980rcpt_count = rcpt_defer_count = rcpt_fail_count =
1981 raw_recipients_count = recipients_count = recipients_list_max = 0;
2e0c1448 1982message_linecount = 0;
059ec3d9 1983message_size = -1;
71fafd95 1984acl_added_headers = NULL;
e7568d51 1985acl_removed_headers = NULL;
059ec3d9 1986queue_only_policy = FALSE;
2679d413
PH
1987rcpt_smtp_response = NULL;
1988rcpt_smtp_response_same = TRUE;
1989rcpt_in_progress = FALSE;
69358f02 1990deliver_freeze = FALSE; /* Can be set by ACL */
6a3f1455 1991freeze_tell = freeze_tell_config; /* Can be set by ACL */
29aba418 1992fake_response = OK; /* Can be set by ACL */
6951ac6c 1993#ifdef WITH_CONTENT_SCAN
8523533c
TK
1994no_mbox_unspool = FALSE; /* Can be set by ACL */
1995#endif
69358f02 1996submission_mode = FALSE; /* Can be set by ACL */
f4ee74ac 1997suppress_local_fixups = suppress_local_fixups_default; /* Can be set by ACL */
69358f02
PH
1998active_local_from_check = local_from_check; /* Can be set by ACL */
1999active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
90341c71
JH
2000sending_ip_address = NULL;
2001return_path = sender_address = NULL;
2002sender_data = NULL; /* Can be set by ACL */
2003deliver_localpart_orig = NULL;
2004deliver_domain_orig = NULL;
2005callout_address = NULL;
2fe1a124 2006submission_name = NULL; /* Can be set by ACL */
059ec3d9
PH
2007raw_sender = NULL; /* After SMTP rewrite, before qualifying */
2008sender_address_unrewritten = NULL; /* Set only after verify rewrite */
2009sender_verified_list = NULL; /* No senders verified */
2010memset(sender_address_cache, 0, sizeof(sender_address_cache));
2011memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
6c1c3d1d 2012
059ec3d9 2013authenticated_sender = NULL;
8523533c
TK
2014#ifdef EXPERIMENTAL_BRIGHTMAIL
2015bmi_run = 0;
2016bmi_verdicts = NULL;
2017#endif
90341c71 2018dnslist_domain = dnslist_matched = NULL;
80a47a2c 2019#ifndef DISABLE_DKIM
9e5d6b55 2020dkim_signers = NULL;
80a47a2c
TK
2021dkim_disable_verify = FALSE;
2022dkim_collect_input = FALSE;
f7572e5a 2023#endif
aa368db3
JH
2024dsn_ret = 0;
2025dsn_envid = NULL;
90341c71 2026deliver_host = deliver_host_address = NULL; /* Can be set by ACL */
aa368db3
JH
2027#ifndef DISABLE_PRDR
2028prdr_requested = FALSE;
2029#endif
8523533c
TK
2030#ifdef EXPERIMENTAL_SPF
2031spf_header_comment = NULL;
2032spf_received = NULL;
8e669ac1 2033spf_result = NULL;
8523533c
TK
2034spf_smtp_comment = NULL;
2035#endif
8c5d388a 2036#ifdef SUPPORT_I18N
d1a13eea
JH
2037message_smtputf8 = FALSE;
2038#endif
059ec3d9
PH
2039body_linecount = body_zerocount = 0;
2040
870f6ba8
TF
2041sender_rate = sender_rate_limit = sender_rate_period = NULL;
2042ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
2043 /* Note that ratelimiters_conn persists across resets. */
2044
38a0a95f 2045/* Reset message ACL variables */
47ca6d6c 2046
38a0a95f 2047acl_var_m = NULL;
059ec3d9
PH
2048
2049/* The message body variables use malloc store. They may be set if this is
2050not the first message in an SMTP session and the previous message caused them
2051to be referenced in an ACL. */
2052
90341c71 2053if (message_body)
059ec3d9
PH
2054 {
2055 store_free(message_body);
2056 message_body = NULL;
2057 }
2058
90341c71 2059if (message_body_end)
059ec3d9
PH
2060 {
2061 store_free(message_body_end);
2062 message_body_end = NULL;
2063 }
2064
2065/* Warning log messages are also saved in malloc store. They are saved to avoid
2066repetition in the same message, but it seems right to repeat them for different
4e88a19f 2067messages. */
059ec3d9 2068
90341c71 2069while (acl_warn_logged)
059ec3d9
PH
2070 {
2071 string_item *this = acl_warn_logged;
2072 acl_warn_logged = acl_warn_logged->next;
2073 store_free(this);
2074 }
90341c71 2075store_reset(reset_point);
059ec3d9
PH
2076}
2077
2078
2079
2080
2081
2082/*************************************************
2083* Initialize for incoming batched SMTP message *
2084*************************************************/
2085
2086/* This function is called from smtp_setup_msg() in the case when
2087smtp_batched_input is true. This happens when -bS is used to pass a whole batch
2088of messages in one file with SMTP commands between them. All errors must be
2089reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
2090relevant. After an error on a sender, or an invalid recipient, the remainder
2091of the message is skipped. The value of received_protocol is already set.
2092
2093Argument: none
2094Returns: > 0 message successfully started (reached DATA)
2095 = 0 QUIT read or end of file reached
2096 < 0 should not occur
2097*/
2098
2099static int
2100smtp_setup_batch_msg(void)
2101{
2102int done = 0;
2103void *reset_point = store_get(0);
2104
2105/* Save the line count at the start of each transaction - single commands
2106like HELO and RSET count as whole transactions. */
2107
2108bsmtp_transaction_linecount = receive_linecount;
2109
2110if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
2111
57cc2785 2112cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg");
059ec3d9
PH
2113smtp_reset(reset_point); /* Reset for start of message */
2114
2115/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
2116value. The values are 2 larger than the required yield of the function. */
2117
2118while (done <= 0)
2119 {
2120 uschar *errmess;
2121 uschar *recipient = NULL;
2122 int start, end, sender_domain, recipient_domain;
2123
bd8fbe36 2124 switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9
PH
2125 {
2126 /* The HELO/EHLO commands set sender_address_helo if they have
2127 valid data; otherwise they are ignored, except that they do
2128 a reset of the state. */
2129
2130 case HELO_CMD:
2131 case EHLO_CMD:
2132
ca86f471 2133 check_helo(smtp_cmd_data);
059ec3d9
PH
2134 /* Fall through */
2135
2136 case RSET_CMD:
57cc2785 2137 cancel_cutthrough_connection(TRUE, US"RSET received");
059ec3d9
PH
2138 smtp_reset(reset_point);
2139 bsmtp_transaction_linecount = receive_linecount;
2140 break;
2141
2142
2143 /* The MAIL FROM command requires an address as an operand. All we
2144 do here is to parse it for syntactic correctness. The form "<>" is
2145 a special case which converts into an empty string. The start/end
2146 pointers in the original are not used further for this address, as
2147 it is the canonical extracted address which is all that is kept. */
2148
2149 case MAIL_CMD:
474f71bf 2150 smtp_mailcmd_count++; /* Count for no-mail log */
059ec3d9
PH
2151 if (sender_address != NULL)
2152 /* The function moan_smtp_batch() does not return. */
3ee512ff 2153 moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
059ec3d9 2154
ca86f471 2155 if (smtp_cmd_data[0] == 0)
059ec3d9 2156 /* The function moan_smtp_batch() does not return. */
3ee512ff 2157 moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
059ec3d9
PH
2158
2159 /* Reset to start of message */
2160
57cc2785 2161 cancel_cutthrough_connection(TRUE, US"MAIL received");
059ec3d9
PH
2162 smtp_reset(reset_point);
2163
2164 /* Apply SMTP rewrite */
2165
2166 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
2167 rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
2168 US"", global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
2169
2170 /* Extract the address; the TRUE flag allows <> as valid */
2171
2172 raw_sender =
2173 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
2174 TRUE);
2175
2176 if (raw_sender == NULL)
2177 /* The function moan_smtp_batch() does not return. */
3ee512ff 2178 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
2179
2180 sender_address = string_copy(raw_sender);
2181
2182 /* Qualify unqualified sender addresses if permitted to do so. */
2183
2184 if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@')
2185 {
2186 if (allow_unqualified_sender)
2187 {
2188 sender_address = rewrite_address_qualify(sender_address, FALSE);
2189 DEBUG(D_receive) debug_printf("unqualified address %s accepted "
2190 "and rewritten\n", raw_sender);
2191 }
2192 /* The function moan_smtp_batch() does not return. */
3ee512ff 2193 else moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
059ec3d9
PH
2194 "a domain");
2195 }
2196 break;
2197
2198
2199 /* The RCPT TO command requires an address as an operand. All we do
2200 here is to parse it for syntactic correctness. There may be any number
2201 of RCPT TO commands, specifying multiple senders. We build them all into
2202 a data structure that is in argc/argv format. The start/end values
2203 given by parse_extract_address are not used, as we keep only the
2204 extracted address. */
2205
2206 case RCPT_CMD:
2207 if (sender_address == NULL)
2208 /* The function moan_smtp_batch() does not return. */
3ee512ff 2209 moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
059ec3d9 2210
ca86f471 2211 if (smtp_cmd_data[0] == 0)
059ec3d9 2212 /* The function moan_smtp_batch() does not return. */
3ee512ff 2213 moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand");
059ec3d9
PH
2214
2215 /* Check maximum number allowed */
2216
2217 if (recipients_max > 0 && recipients_count + 1 > recipients_max)
2218 /* The function moan_smtp_batch() does not return. */
3ee512ff 2219 moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
059ec3d9
PH
2220 recipients_max_reject? "552": "452");
2221
2222 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
2223 recipient address */
2224
2685d6e0
JH
2225 recipient = rewrite_existflags & rewrite_smtp
2226 ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
2227 global_rewrite_rules)
2228 : smtp_cmd_data;
059ec3d9 2229
059ec3d9
PH
2230 recipient = parse_extract_address(recipient, &errmess, &start, &end,
2231 &recipient_domain, FALSE);
059ec3d9 2232
2685d6e0 2233 if (!recipient)
059ec3d9 2234 /* The function moan_smtp_batch() does not return. */
3ee512ff 2235 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
2236
2237 /* If the recipient address is unqualified, qualify it if permitted. Then
2238 add it to the list of recipients. */
2239
2240 if (recipient_domain == 0)
2241 {
2242 if (allow_unqualified_recipient)
2243 {
2244 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
2245 recipient);
2246 recipient = rewrite_address_qualify(recipient, TRUE);
2247 }
2248 /* The function moan_smtp_batch() does not return. */
3ee512ff 2249 else moan_smtp_batch(smtp_cmd_buffer, "501 recipient address must contain "
059ec3d9
PH
2250 "a domain");
2251 }
2252 receive_add_recipient(recipient, -1);
2253 break;
2254
2255
2256 /* The DATA command is legal only if it follows successful MAIL FROM
2257 and RCPT TO commands. This function is complete when a valid DATA
2258 command is encountered. */
2259
2260 case DATA_CMD:
2261 if (sender_address == NULL || recipients_count <= 0)
2262 {
2263 /* The function moan_smtp_batch() does not return. */
2264 if (sender_address == NULL)
3ee512ff 2265 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
2266 "503 MAIL FROM:<sender> command must precede DATA");
2267 else
3ee512ff 2268 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
2269 "503 RCPT TO:<recipient> must precede DATA");
2270 }
2271 else
2272 {
2273 done = 3; /* DATA successfully achieved */
2274 message_ended = END_NOTENDED; /* Indicate in middle of message */
2275 }
2276 break;
2277
2278
2279 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
2280
2281 case VRFY_CMD:
2282 case EXPN_CMD:
2283 case HELP_CMD:
2284 case NOOP_CMD:
2285 case ETRN_CMD:
2286 bsmtp_transaction_linecount = receive_linecount;
2287 break;
2288
2289
2290 case EOF_CMD:
2291 case QUIT_CMD:
2292 done = 2;
2293 break;
2294
2295
2296 case BADARG_CMD:
2297 /* The function moan_smtp_batch() does not return. */
3ee512ff 2298 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
059ec3d9
PH
2299 break;
2300
2301
2302 case BADCHAR_CMD:
2303 /* The function moan_smtp_batch() does not return. */
3ee512ff 2304 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
059ec3d9
PH
2305 break;
2306
2307
2308 default:
2309 /* The function moan_smtp_batch() does not return. */
3ee512ff 2310 moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
059ec3d9
PH
2311 break;
2312 }
2313 }
2314
2315return done - 2; /* Convert yield values */
2316}
2317
2318
2319
2320
cf0c6164
JH
2321static BOOL
2322smtp_log_tls_fail(uschar * errstr)
2323{
2324uschar * conn_info = smtp_get_connection_info();
2325
2326if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
2327/* I'd like to get separated H= here, but too hard for now */
2328
2329log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
2330return FALSE;
2331}
2332
2333
059ec3d9
PH
2334/*************************************************
2335* Start an SMTP session *
2336*************************************************/
2337
2338/* This function is called at the start of an SMTP session. Thereafter,
2339smtp_setup_msg() is called to initiate each separate message. This
2340function does host-specific testing, and outputs the banner line.
2341
2342Arguments: none
2343Returns: FALSE if the session can not continue; something has
2344 gone wrong, or the connection to the host is blocked
2345*/
2346
2347BOOL
2348smtp_start_session(void)
2349{
2350int size = 256;
4e88a19f
PH
2351int ptr, esclen;
2352uschar *user_msg, *log_msg;
2353uschar *code, *esc;
059ec3d9
PH
2354uschar *p, *s, *ss;
2355
b4ed4da0
PH
2356smtp_connection_start = time(NULL);
2357for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
2358 smtp_connection_had[smtp_ch_index] = SCH_NONE;
2359smtp_ch_index = 0;
2360
00f00ca5
PH
2361/* Default values for certain variables */
2362
059ec3d9 2363helo_seen = esmtp = helo_accept_junk = FALSE;
b4ed4da0 2364smtp_mailcmd_count = 0;
059ec3d9
PH
2365count_nonmail = TRUE_UNSET;
2366synprot_error_count = unknown_command_count = nonmail_command_count = 0;
2367smtp_delay_mail = smtp_rlm_base;
2368auth_advertised = FALSE;
2369pipelining_advertised = FALSE;
cf8b11a5 2370pipelining_enable = TRUE;
059ec3d9 2371sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
8f128379 2372smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
059ec3d9 2373
33d73e3b
PH
2374/* If receiving by -bs from a trusted user, or testing with -bh, we allow
2375authentication settings from -oMaa to remain in force. */
2376
2377if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL;
059ec3d9
PH
2378authenticated_by = NULL;
2379
2380#ifdef SUPPORT_TLS
817d9f57 2381tls_in.cipher = tls_in.peerdn = NULL;
9d1c15ef
JH
2382tls_in.ourcert = tls_in.peercert = NULL;
2383tls_in.sni = NULL;
44662487 2384tls_in.ocsp = OCSP_NOT_REQ;
059ec3d9
PH
2385tls_advertised = FALSE;
2386#endif
6c1c3d1d 2387dsn_advertised = FALSE;
8c5d388a 2388#ifdef SUPPORT_I18N
d1a13eea
JH
2389smtputf8_advertised = FALSE;
2390#endif
059ec3d9
PH
2391
2392/* Reset ACL connection variables */
2393
38a0a95f 2394acl_var_c = NULL;
059ec3d9 2395
ca86f471 2396/* Allow for trailing 0 in the command and data buffers. */
3ee512ff 2397
bd8fbe36 2398if (!(smtp_cmd_buffer = US malloc(2*SMTP_CMD_BUFFER_SIZE + 2)))
059ec3d9
PH
2399 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2400 "malloc() failed for SMTP command buffer");
40c90bca 2401
2416c261 2402smtp_cmd_buffer[0] = 0;
bd8fbe36 2403smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1;
059ec3d9
PH
2404
2405/* For batched input, the protocol setting can be overridden from the
2406command line by a trusted caller. */
2407
2408if (smtp_batched_input)
2409 {
40c90bca 2410 if (!received_protocol) received_protocol = US"local-bsmtp";
059ec3d9
PH
2411 }
2412
2413/* For non-batched SMTP input, the protocol setting is forced here. It will be
2414reset later if any of EHLO/AUTH/STARTTLS are received. */
2415
2416else
2417 received_protocol =
e524074d 2418 (sender_host_address ? protocols : protocols_local) [pnormal];
059ec3d9
PH
2419
2420/* Set up the buffer for inputting using direct read() calls, and arrange to
2421call the local functions instead of the standard C ones. */
2422
bd8fbe36 2423if (!(smtp_inbuffer = (uschar *)malloc(IN_BUFFER_SIZE)))
059ec3d9 2424 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
40c90bca 2425
059ec3d9 2426receive_getc = smtp_getc;
0d81dabc 2427receive_getbuf = smtp_getbuf;
584e96c6 2428receive_get_cache = smtp_get_cache;
059ec3d9
PH
2429receive_ungetc = smtp_ungetc;
2430receive_feof = smtp_feof;
2431receive_ferror = smtp_ferror;
58eb016e 2432receive_smtp_buffered = smtp_buffered;
059ec3d9
PH
2433smtp_inptr = smtp_inend = smtp_inbuffer;
2434smtp_had_eof = smtp_had_error = 0;
2435
2436/* Set up the message size limit; this may be host-specific */
2437
d45b1de8
PH
2438thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
2439if (expand_string_message != NULL)
059ec3d9
PH
2440 {
2441 if (thismessage_size_limit == -1)
2442 log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
2443 "%s", expand_string_message);
2444 else
2445 log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: "
2446 "%s", expand_string_message);
2447 smtp_closedown(US"Temporary local problem - please try later");
2448 return FALSE;
2449 }
2450
2451/* When a message is input locally via the -bs or -bS options, sender_host_
2452unknown is set unless -oMa was used to force an IP address, in which case it
2453is checked like a real remote connection. When -bs is used from inetd, this
2454flag is not set, causing the sending host to be checked. The code that deals
2455with IP source routing (if configured) is never required for -bs or -bS and
2456the flag sender_host_notsocket is used to suppress it.
2457
2458If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
2459reserve for certain hosts and/or networks. */
2460
2461if (!sender_host_unknown)
2462 {
2463 int rc;
2464 BOOL reserved_host = FALSE;
2465
2466 /* Look up IP options (source routing info) on the socket if this is not an
2467 -oMa "host", and if any are found, log them and drop the connection.
2468
2469 Linux (and others now, see below) is different to everyone else, so there
2470 has to be some conditional compilation here. Versions of Linux before 2.1.15
2471 used a structure whose name was "options". Somebody finally realized that
2472 this name was silly, and it got changed to "ip_options". I use the
2473 newer name here, but there is a fudge in the script that sets up os.h
2474 to define a macro in older Linux systems.
2475
2476 Sigh. Linux is a fast-moving target. Another generation of Linux uses
2477 glibc 2, which has chosen ip_opts for the structure name. This is now
2478 really a glibc thing rather than a Linux thing, so the condition name
2479 has been changed to reflect this. It is relevant also to GNU/Hurd.
2480
2481 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
2482 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
2483 a special macro defined in the os.h file.
2484
2485 Some DGUX versions on older hardware appear not to support IP options at
2486 all, so there is now a general macro which can be set to cut out this
2487 support altogether.
2488
2489 How to do this properly in IPv6 is not yet known. */
2490
2491 #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
2492
2493 #ifdef GLIBC_IP_OPTIONS
2494 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
2495 #define OPTSTYLE 1
2496 #else
2497 #define OPTSTYLE 2
2498 #endif
2499 #elif defined DARWIN_IP_OPTIONS
2500 #define OPTSTYLE 2
2501 #else
2502 #define OPTSTYLE 3
2503 #endif
2504
2505 if (!host_checking && !sender_host_notsocket)
2506 {
2507 #if OPTSTYLE == 1
36a3b041 2508 EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
059ec3d9
PH
2509 struct ip_options *ipopt = store_get(optlen);
2510 #elif OPTSTYLE == 2
2511 struct ip_opts ipoptblock;
2512 struct ip_opts *ipopt = &ipoptblock;
36a3b041 2513 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2514 #else
2515 struct ipoption ipoptblock;
2516 struct ipoption *ipopt = &ipoptblock;
36a3b041 2517 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2518 #endif
2519
2520 /* Occasional genuine failures of getsockopt() have been seen - for
2521 example, "reset by peer". Therefore, just log and give up on this
2522 call, unless the error is ENOPROTOOPT. This error is given by systems
2523 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
2524 of writing. So for that error, carry on - we just can't do an IP options
2525 check. */
2526
2527 DEBUG(D_receive) debug_printf("checking for IP options\n");
2528
2529 if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt),
2530 &optlen) < 0)
2531 {
2532 if (errno != ENOPROTOOPT)
2533 {
2534 log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
2535 host_and_ident(FALSE), strerror(errno));
925ac8e4 2536 smtp_printf("451 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2537 return FALSE;
2538 }
2539 }
2540
2541 /* Deal with any IP options that are set. On the systems I have looked at,
2542 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
2543 more logging data than will fit in big_buffer. Nevertheless, after somebody
2544 questioned this code, I've added in some paranoid checking. */
2545
2546 else if (optlen > 0)
2547 {
2548 uschar *p = big_buffer;
2549 uschar *pend = big_buffer + big_buffer_size;
2550 uschar *opt, *adptr;
2551 int optcount;
2552 struct in_addr addr;
2553
2554 #if OPTSTYLE == 1
2555 uschar *optstart = (uschar *)(ipopt->__data);
2556 #elif OPTSTYLE == 2
2557 uschar *optstart = (uschar *)(ipopt->ip_opts);
2558 #else
2559 uschar *optstart = (uschar *)(ipopt->ipopt_list);
2560 #endif
2561
2562 DEBUG(D_receive) debug_printf("IP options exist\n");
2563
2564 Ustrcpy(p, "IP options on incoming call:");
2565 p += Ustrlen(p);
2566
2567 for (opt = optstart; opt != NULL &&
2568 opt < (uschar *)(ipopt) + optlen;)
2569 {
2570 switch (*opt)
2571 {
2572 case IPOPT_EOL:
2573 opt = NULL;
2574 break;
2575
2576 case IPOPT_NOP:
2577 opt++;
2578 break;
2579
2580 case IPOPT_SSRR:
2581 case IPOPT_LSRR:
2582 if (!string_format(p, pend-p, " %s [@%s",
2583 (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
2584 #if OPTSTYLE == 1
2585 inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
2586 #elif OPTSTYLE == 2
2587 inet_ntoa(ipopt->ip_dst)))
2588 #else
2589 inet_ntoa(ipopt->ipopt_dst)))
2590 #endif
2591 {
2592 opt = NULL;
2593 break;
2594 }
2595
2596 p += Ustrlen(p);
2597 optcount = (opt[1] - 3) / sizeof(struct in_addr);
2598 adptr = opt + 3;
2599 while (optcount-- > 0)
2600 {
2601 memcpy(&addr, adptr, sizeof(addr));
2602 if (!string_format(p, pend - p - 1, "%s%s",
2603 (optcount == 0)? ":" : "@", inet_ntoa(addr)))
2604 {
2605 opt = NULL;
2606 break;
2607 }
2608 p += Ustrlen(p);
2609 adptr += sizeof(struct in_addr);
2610 }
2611 *p++ = ']';
2612 opt += opt[1];
2613 break;
2614
2615 default:
2616 {
2617 int i;
2618 if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
2619 Ustrcat(p, "[ ");
2620 p += 2;
2621 for (i = 0; i < opt[1]; i++)
2622 {
2623 sprintf(CS p, "%2.2x ", opt[i]);
2624 p += 3;
2625 }
2626 *p++ = ']';
2627 }
2628 opt += opt[1];
2629 break;
2630 }
2631 }
2632
2633 *p = 0;
2634 log_write(0, LOG_MAIN, "%s", big_buffer);
2635
2636 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2637
2638 log_write(0, LOG_MAIN|LOG_REJECT,
2639 "connection from %s refused (IP options)", host_and_ident(FALSE));
2640
925ac8e4 2641 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2642 return FALSE;
2643 }
2644
2645 /* Length of options = 0 => there are no options */
2646
2647 else DEBUG(D_receive) debug_printf("no IP options found\n");
2648 }
2649 #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
2650
2651 /* Set keep-alive in socket options. The option is on by default. This
2652 setting is an attempt to get rid of some hanging connections that stick in
2653 read() when the remote end (usually a dialup) goes away. */
2654
2655 if (smtp_accept_keepalive && !sender_host_notsocket)
2656 ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
2657
2658 /* If the current host matches host_lookup, set the name by doing a
2659 reverse lookup. On failure, sender_host_name will be NULL and
2660 host_lookup_failed will be TRUE. This may or may not be serious - optional
2661 checks later. */
2662
2663 if (verify_check_host(&host_lookup) == OK)
2664 {
2665 (void)host_name_lookup();
2666 host_build_sender_fullhost();
2667 }
2668
2669 /* Delay this until we have the full name, if it is looked up. */
2670
2671 set_process_info("handling incoming connection from %s",
2672 host_and_ident(FALSE));
2673
1ad6489e
JH
2674 /* Expand smtp_receive_timeout, if needed */
2675
2676 if (smtp_receive_timeout_s)
2677 {
2678 uschar * exp;
2679 if ( !(exp = expand_string(smtp_receive_timeout_s))
2680 || !(*exp)
2681 || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0
2682 )
2683 log_write(0, LOG_MAIN|LOG_PANIC,
2684 "bad value for smtp_receive_timeout: '%s'", exp ? exp : US"");
2685 }
2686
059ec3d9
PH
2687 /* Test for explicit connection rejection */
2688
2689 if (verify_check_host(&host_reject_connection) == OK)
2690 {
2691 log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
2692 "from %s (host_reject_connection)", host_and_ident(FALSE));
925ac8e4 2693 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2694 return FALSE;
2695 }
2696
afb3eaaf
PH
2697 /* Test with TCP Wrappers if so configured. There is a problem in that
2698 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2699 such as disks dying. In these cases, it is desirable to reject with a 4xx
2700 error instead of a 5xx error. There isn't a "right" way to detect such
2701 problems. The following kludge is used: errno is zeroed before calling
2702 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2703 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2704 not exist). */
059ec3d9 2705
1811cb4c 2706#ifdef USE_TCP_WRAPPERS
afb3eaaf 2707 errno = 0;
1811cb4c 2708 if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name)))
5dc43717
JJ
2709 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
2710 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
2711 expand_string_message);
1811cb4c 2712
5dc43717 2713 if (!hosts_ctl(tcp_wrappers_name,
1811cb4c
JH
2714 sender_host_name ? CS sender_host_name : STRING_UNKNOWN,
2715 sender_host_address ? CS sender_host_address : STRING_UNKNOWN,
2716 sender_ident ? CS sender_ident : STRING_UNKNOWN))
059ec3d9 2717 {
afb3eaaf
PH
2718 if (errno == 0 || errno == ENOENT)
2719 {
2720 HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
2721 log_write(L_connection_reject,
2722 LOG_MAIN|LOG_REJECT, "refused connection from %s "
2723 "(tcp wrappers)", host_and_ident(FALSE));
925ac8e4 2724 smtp_printf("554 SMTP service not available\r\n", FALSE);
afb3eaaf
PH
2725 }
2726 else
2727 {
2728 int save_errno = errno;
2729 HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
2730 "errno value %d\n", save_errno);
2731 log_write(L_connection_reject,
2732 LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
2733 "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
925ac8e4 2734 smtp_printf("451 Temporary local problem - please try later\r\n", FALSE);
afb3eaaf 2735 }
059ec3d9
PH
2736 return FALSE;
2737 }
1811cb4c 2738#endif
059ec3d9 2739
b01dd148
PH
2740 /* Check for reserved slots. The value of smtp_accept_count has already been
2741 incremented to include this process. */
059ec3d9
PH
2742
2743 if (smtp_accept_max > 0 &&
b01dd148 2744 smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
059ec3d9
PH
2745 {
2746 if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
2747 {
2748 log_write(L_connection_reject,
2749 LOG_MAIN, "temporarily refused connection from %s: not in "
2750 "reserve list: connected=%d max=%d reserve=%d%s",
b01dd148 2751 host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
059ec3d9
PH
2752 smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
2753 smtp_printf("421 %s: Too many concurrent SMTP connections; "
925ac8e4 2754 "please try again later\r\n", FALSE, smtp_active_hostname);
059ec3d9
PH
2755 return FALSE;
2756 }
2757 reserved_host = TRUE;
2758 }
2759
2760 /* If a load level above which only messages from reserved hosts are
2761 accepted is set, check the load. For incoming calls via the daemon, the
2762 check is done in the superior process if there are no reserved hosts, to
2763 save a fork. In all cases, the load average will already be available
2764 in a global variable at this point. */
2765
2766 if (smtp_load_reserve >= 0 &&
2767 load_average > smtp_load_reserve &&
2768 !reserved_host &&
2769 verify_check_host(&smtp_reserve_hosts) != OK)
2770 {
2771 log_write(L_connection_reject,
2772 LOG_MAIN, "temporarily refused connection from %s: not in "
2773 "reserve list and load average = %.2f", host_and_ident(FALSE),
2774 (double)load_average/1000.0);
925ac8e4 2775 smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE,
059ec3d9
PH
2776 smtp_active_hostname);
2777 return FALSE;
2778 }
2779
2780 /* Determine whether unqualified senders or recipients are permitted
2781 for this host. Unfortunately, we have to do this every time, in order to
2782 set the flags so that they can be inspected when considering qualifying
2783 addresses in the headers. For a site that permits no qualification, this
2784 won't take long, however. */
2785
2786 allow_unqualified_sender =
2787 verify_check_host(&sender_unqualified_hosts) == OK;
2788
2789 allow_unqualified_recipient =
2790 verify_check_host(&recipient_unqualified_hosts) == OK;
2791
2792 /* Determine whether HELO/EHLO is required for this host. The requirement
2793 can be hard or soft. */
2794
2795 helo_required = verify_check_host(&helo_verify_hosts) == OK;
2796 if (!helo_required)
2797 helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
2798
2799 /* Determine whether this hosts is permitted to send syntactic junk
2800 after a HELO or EHLO command. */
2801
2802 helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
2803 }
2804
2805/* For batch SMTP input we are now done. */
2806
2807if (smtp_batched_input) return TRUE;
2808
a3c86431
TL
2809/* If valid Proxy Protocol source is connecting, set up session.
2810 * Failure will not allow any SMTP function other than QUIT. */
1811cb4c
JH
2811
2812#ifdef SUPPORT_PROXY
a3c86431
TL
2813proxy_session = FALSE;
2814proxy_session_failed = FALSE;
2815if (check_proxy_protocol_host())
1811cb4c
JH
2816 setup_proxy_protocol_host();
2817#endif
2818
2819 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2820 smtps port for use with older style SSL MTAs. */
2821
2822#ifdef SUPPORT_TLS
cf0c6164
JH
2823 if (tls_in.on_connect && tls_server_start(tls_require_ciphers, &user_msg) != OK)
2824 return smtp_log_tls_fail(user_msg);
a3c86431
TL
2825#endif
2826
1811cb4c 2827/* Run the connect ACL if it exists */
059ec3d9 2828
4e88a19f 2829user_msg = NULL;
3cc3f762 2830if (acl_smtp_connect)
059ec3d9
PH
2831 {
2832 int rc;
3cc3f762
JH
2833 if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
2834 &log_msg)) != OK)
059ec3d9 2835 {
3cc3f762 2836 (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
059ec3d9
PH
2837 return FALSE;
2838 }
2839 }
2840
2841/* Output the initial message for a two-way SMTP connection. It may contain
2842newlines, which then cause a multi-line response to be given. */
2843
4e88a19f
PH
2844code = US"220"; /* Default status code */
2845esc = US""; /* Default extended status code */
2846esclen = 0; /* Length of esc */
2847
d4ff61d1 2848if (!user_msg)
4e88a19f 2849 {
d4ff61d1 2850 if (!(s = expand_string(smtp_banner)))
4e88a19f
PH
2851 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
2852 "failed: %s", smtp_banner, expand_string_message);
2853 }
2854else
2855 {
2856 int codelen = 3;
2857 s = user_msg;
4f6ae5c3 2858 smtp_message_code(&code, &codelen, &s, NULL, TRUE);
d6a96edc 2859 if (codelen > 4)
4e88a19f
PH
2860 {
2861 esc = code + 4;
2862 esclen = codelen - 4;
2863 }
2864 }
059ec3d9
PH
2865
2866/* Remove any terminating newlines; might as well remove trailing space too */
2867
2868p = s + Ustrlen(s);
2869while (p > s && isspace(p[-1])) p--;
2870*p = 0;
2871
2872/* It seems that CC:Mail is braindead, and assumes that the greeting message
2873is all contained in a single IP packet. The original code wrote out the
2874greeting using several calls to fprint/fputc, and on busy servers this could
2875cause it to be split over more than one packet - which caused CC:Mail to fall
2876over when it got the second part of the greeting after sending its first
2877command. Sigh. To try to avoid this, build the complete greeting message
2878first, and output it in one fell swoop. This gives a better chance of it
2879ending up as a single packet. */
2880
2881ss = store_get(size);
2882ptr = 0;
2883
2884p = s;
2885do /* At least once, in case we have an empty string */
2886 {
2887 int len;
2888 uschar *linebreak = Ustrchr(p, '\n');
c2f669a4 2889 ss = string_catn(ss, &size, &ptr, code, 3);
059ec3d9
PH
2890 if (linebreak == NULL)
2891 {
2892 len = Ustrlen(p);
c2f669a4 2893 ss = string_catn(ss, &size, &ptr, US" ", 1);
059ec3d9
PH
2894 }
2895 else
2896 {
2897 len = linebreak - p;
c2f669a4 2898 ss = string_catn(ss, &size, &ptr, US"-", 1);
059ec3d9 2899 }
c2f669a4
JH
2900 ss = string_catn(ss, &size, &ptr, esc, esclen);
2901 ss = string_catn(ss, &size, &ptr, p, len);
2902 ss = string_catn(ss, &size, &ptr, US"\r\n", 2);
059ec3d9
PH
2903 p += len;
2904 if (linebreak != NULL) p++;
2905 }
2906while (*p != 0);
2907
2908ss[ptr] = 0; /* string_cat leaves room for this */
2909
2910/* Before we write the banner, check that there is no input pending, unless
2911this synchronisation check is disabled. */
2912
a14e5636 2913if (!check_sync())
059ec3d9 2914 {
40525d07
JH
2915 unsigned n = smtp_inend - smtp_inptr;
2916 if (n > 32) n = 32;
2917
a14e5636
PH
2918 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
2919 "synchronization error (input sent without waiting for greeting): "
2920 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
40525d07 2921 string_printing(string_copyn(smtp_inptr, n)));
925ac8e4 2922 smtp_printf("554 SMTP synchronization error\r\n", FALSE);
a14e5636 2923 return FALSE;
059ec3d9
PH
2924 }
2925
2926/* Now output the banner */
2927
925ac8e4 2928smtp_printf("%s", FALSE, ss);
059ec3d9
PH
2929return TRUE;
2930}
2931
2932
2933
2934
2935
2936/*************************************************
2937* Handle SMTP syntax and protocol errors *
2938*************************************************/
2939
2940/* Write to the log for SMTP syntax errors in incoming commands, if configured
2941to do so. Then transmit the error response. The return value depends on the
2942number of syntax and protocol errors in this SMTP session.
2943
2944Arguments:
2945 type error type, given as a log flag bit
2946 code response code; <= 0 means don't send a response
2947 data data to reflect in the response (can be NULL)
2948 errmess the error message
2949
2950Returns: -1 limit of syntax/protocol errors NOT exceeded
2951 +1 limit of syntax/protocol errors IS exceeded
2952
2953These values fit in with the values of the "done" variable in the main
2954processing loop in smtp_setup_msg(). */
2955
2956static int
2957synprot_error(int type, int code, uschar *data, uschar *errmess)
2958{
2959int yield = -1;
2960
2961log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
2962 (type == L_smtp_syntax_error)? "syntax" : "protocol",
3ee512ff 2963 string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
059ec3d9
PH
2964
2965if (++synprot_error_count > smtp_max_synprot_errors)
2966 {
2967 yield = 1;
2968 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
2969 "syntax or protocol errors (last command was \"%s\")",
0ebc4d69 2970 host_and_ident(FALSE), string_printing(smtp_cmd_buffer));
059ec3d9
PH
2971 }
2972
2973if (code > 0)
2974 {
925ac8e4
JH
2975 smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ',
2976 data ? data : US"", data ? US": " : US"", errmess);
059ec3d9 2977 if (yield == 1)
925ac8e4 2978 smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code);
059ec3d9
PH
2979 }
2980
2981return yield;
2982}
2983
2984
2985
2986
2987/*************************************************
059ec3d9
PH
2988* Send SMTP response, possibly multiline *
2989*************************************************/
2990
2991/* There are, it seems, broken clients out there that cannot handle multiline
2992responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
2993output nothing for non-final calls, and only the first line for anything else.
2994
2995Arguments:
a5bd321b 2996 code SMTP code, may involve extended status codes
d6a96edc 2997 codelen length of smtp code; if > 4 there's an ESC
059ec3d9
PH
2998 final FALSE if the last line isn't the final line
2999 msg message text, possibly containing newlines
3000
3001Returns: nothing
3002*/
3003
3004void
a5bd321b 3005smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
059ec3d9 3006{
a5bd321b
PH
3007int esclen = 0;
3008uschar *esc = US"";
3009
059ec3d9
PH
3010if (!final && no_multiline_responses) return;
3011
d6a96edc 3012if (codelen > 4)
a5bd321b
PH
3013 {
3014 esc = code + 4;
3015 esclen = codelen - 4;
3016 }
3017
2679d413
PH
3018/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
3019have had the same. Note: this code is also present in smtp_printf(). It would
3020be tidier to have it only in one place, but when it was added, it was easier to
3021do it that way, so as not to have to mess with the code for the RCPT command,
3022which sometimes uses smtp_printf() and sometimes smtp_respond(). */
3023
3024if (rcpt_in_progress)
3025 {
3026 if (rcpt_smtp_response == NULL)
3027 rcpt_smtp_response = string_copy(msg);
3028 else if (rcpt_smtp_response_same &&
3029 Ustrcmp(rcpt_smtp_response, msg) != 0)
3030 rcpt_smtp_response_same = FALSE;
3031 rcpt_in_progress = FALSE;
3032 }
3033
e5de01f0 3034/* Now output the message, splitting it up into multiple lines if necessary.
925ac8e4
JH
3035We only handle pipelining these responses as far as nonfinal/final groups,
3036not the whole MAIL/RCPT/DATA response set. */
2679d413 3037
059ec3d9
PH
3038for (;;)
3039 {
3040 uschar *nl = Ustrchr(msg, '\n');
3041 if (nl == NULL)
3042 {
925ac8e4 3043 smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg);
059ec3d9
PH
3044 return;
3045 }
3046 else if (nl[1] == 0 || no_multiline_responses)
3047 {
925ac8e4 3048 smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc,
a5bd321b 3049 (int)(nl - msg), msg);
059ec3d9
PH
3050 return;
3051 }
3052 else
3053 {
925ac8e4 3054 smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg);
059ec3d9
PH
3055 msg = nl + 1;
3056 while (isspace(*msg)) msg++;
3057 }
3058 }
3059}
3060
3061
3062
3063
3064/*************************************************
4e88a19f
PH
3065* Parse user SMTP message *
3066*************************************************/
3067
3068/* This function allows for user messages overriding the response code details
3069by providing a suitable response code string at the start of the message
3070user_msg. Check the message for starting with a response code and optionally an
3071extended status code. If found, check that the first digit is valid, and if so,
3072change the code pointer and length to use the replacement. An invalid code
3073causes a panic log; in this case, if the log messages is the same as the user
3074message, we must also adjust the value of the log message to show the code that
3075is actually going to be used (the original one).
3076
3077This function is global because it is called from receive.c as well as within
3078this module.
3079
d6a96edc
PH
3080Note that the code length returned includes the terminating whitespace
3081character, which is always included in the regex match.
3082
4e88a19f
PH
3083Arguments:
3084 code SMTP code, may involve extended status codes
d6a96edc 3085 codelen length of smtp code; if > 4 there's an ESC
4e88a19f
PH
3086 msg message text
3087 log_msg optional log message, to be adjusted with the new SMTP code
4f6ae5c3 3088 check_valid if true, verify the response code
4e88a19f
PH
3089
3090Returns: nothing
3091*/
3092
3093void
4f6ae5c3
JH
3094smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg,
3095 BOOL check_valid)
4e88a19f
PH
3096{
3097int n;
3098int ovector[3];
3099
4f6ae5c3 3100if (!msg || !*msg) return;
4e88a19f 3101
4f6ae5c3
JH
3102if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
3103 PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return;
4e88a19f 3104
4f6ae5c3 3105if (check_valid && (*msg)[0] != (*code)[0])
4e88a19f
PH
3106 {
3107 log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
3108 "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
3109 if (log_msg != NULL && *log_msg == *msg)
3110 *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
3111 }
3112else
3113 {
3114 *code = *msg;
3115 *codelen = ovector[1]; /* Includes final space */
3116 }
3117*msg += ovector[1]; /* Chop the code off the message */
3118return;
3119}
3120
3121
3122
3123
3124/*************************************************
059ec3d9
PH
3125* Handle an ACL failure *
3126*************************************************/
3127
3128/* This function is called when acl_check() fails. As well as calls from within
3129this module, it is called from receive.c for an ACL after DATA. It sorts out
3130logging the incident, and sets up the error response. A message containing
3131newlines is turned into a multiline SMTP response, but for logging, only the
3132first line is used.
3133
a5bd321b
PH
3134There's a table of default permanent failure response codes to use in
3135globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
3136defaults disabled in Exim. However, discussion in connection with RFC 821bis
3137(aka RFC 2821) has concluded that the response should be 252 in the disabled
3138state, because there are broken clients that try VRFY before RCPT. A 5xx
3139response should be given only when the address is positively known to be
4f6ae5c3
JH
3140undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
3141no explicit code, but if there is one we let it know best.
3142Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
a5bd321b
PH
3143
3144From Exim 4.63, it is possible to override the response code details by
3145providing a suitable response code string at the start of the message provided
3146in user_msg. The code's first digit is checked for validity.
059ec3d9
PH
3147
3148Arguments:
4f6ae5c3
JH
3149 where where the ACL was called from
3150 rc the failure code
3151 user_msg a message that can be included in an SMTP response
3152 log_msg a message for logging
059ec3d9
PH
3153
3154Returns: 0 in most cases
3155 2 if the failure code was FAIL_DROP, in which case the
3156 SMTP connection should be dropped (this value fits with the
3157 "done" variable in smtp_setup_msg() below)
3158*/
3159
3160int
3161smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
3162{
059ec3d9 3163BOOL drop = rc == FAIL_DROP;
a5bd321b 3164int codelen = 3;
a5bd321b 3165uschar *smtp_code;
059ec3d9
PH
3166uschar *lognl;
3167uschar *sender_info = US"";
64ffc24f 3168uschar *what =
8523533c 3169#ifdef WITH_CONTENT_SCAN
3cc3f762 3170 where == ACL_WHERE_MIME ? US"during MIME ACL checks" :
8e669ac1 3171#endif
3cc3f762
JH
3172 where == ACL_WHERE_PREDATA ? US"DATA" :
3173 where == ACL_WHERE_DATA ? US"after DATA" :
8ccd00b1 3174#ifndef DISABLE_PRDR
3cc3f762 3175 where == ACL_WHERE_PRDR ? US"after DATA PRDR" :
fd98a5c6 3176#endif
3cc3f762
JH
3177 smtp_cmd_data ?
3178 string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) :
3179 string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]);
059ec3d9
PH
3180
3181if (drop) rc = FAIL;
3182
4e88a19f 3183/* Set the default SMTP code, and allow a user message to change it. */
a5bd321b 3184
4f6ae5c3
JH
3185smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451";
3186smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg,
3187 where != ACL_WHERE_VRFY);
a5bd321b 3188
059ec3d9
PH
3189/* We used to have sender_address here; however, there was a bug that was not
3190updating sender_address after a rewrite during a verify. When this bug was
3191fixed, sender_address at this point became the rewritten address. I'm not sure
3192this is what should be logged, so I've changed to logging the unrewritten
3193address to retain backward compatibility. */
3194
8523533c 3195#ifndef WITH_CONTENT_SCAN
059ec3d9 3196if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
8523533c
TK
3197#else
3198if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
3199#endif
059ec3d9 3200 {
b98bb9ac
PP
3201 sender_info = string_sprintf("F=<%s>%s%s%s%s ",
3202 sender_address_unrewritten ? sender_address_unrewritten : sender_address,
3203 sender_host_authenticated ? US" A=" : US"",
3204 sender_host_authenticated ? sender_host_authenticated : US"",
3205 sender_host_authenticated && authenticated_id ? US":" : US"",
3206 sender_host_authenticated && authenticated_id ? authenticated_id : US""
3207 );
059ec3d9
PH
3208 }
3209
3210/* If there's been a sender verification failure with a specific message, and
3211we have not sent a response about it yet, do so now, as a preliminary line for
278c6e6c
PH
3212failures, but not defers. However, always log it for defer, and log it for fail
3213unless the sender_verify_fail log selector has been turned off. */
059ec3d9 3214
02b41d71 3215if (sender_verified_failed &&
059ec3d9
PH
3216 !testflag(sender_verified_failed, af_sverify_told))
3217 {
2679d413
PH
3218 BOOL save_rcpt_in_progress = rcpt_in_progress;
3219 rcpt_in_progress = FALSE; /* So as not to treat these as the error */
3220
059ec3d9
PH
3221 setflag(sender_verified_failed, af_sverify_told);
3222
6c6d6e48 3223 if (rc != FAIL || LOGGING(sender_verify_fail))
278c6e6c
PH
3224 log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
3225 host_and_ident(TRUE),
3226 ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
3227 sender_verified_failed->address,
3228 (sender_verified_failed->message == NULL)? US"" :
3229 string_sprintf(": %s", sender_verified_failed->message));
059ec3d9 3230
02b41d71 3231 if (rc == FAIL && sender_verified_failed->user_message)
a5bd321b 3232 smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
059ec3d9
PH
3233 testflag(sender_verified_failed, af_verify_pmfail)?
3234 "Postmaster verification failed while checking <%s>\n%s\n"
3235 "Several RFCs state that you are required to have a postmaster\n"
3236 "mailbox for each mail domain. This host does not accept mail\n"
3237 "from domains whose servers reject the postmaster address."
3238 :
3239 testflag(sender_verified_failed, af_verify_nsfail)?
3240 "Callback setup failed while verifying <%s>\n%s\n"
3241 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
3242 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
3243 "RFC requirements, and stops you from receiving standard bounce\n"
3244 "messages. This host does not accept mail from domains whose servers\n"
3245 "refuse bounces."
3246 :
3247 "Verification failed for <%s>\n%s",
3248 sender_verified_failed->address,
3249 sender_verified_failed->user_message));
2679d413
PH
3250
3251 rcpt_in_progress = save_rcpt_in_progress;
059ec3d9
PH
3252 }
3253
3254/* Sort out text for logging */
3255
3cc3f762
JH
3256log_msg = log_msg ? string_sprintf(": %s", log_msg) : US"";
3257if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0;
059ec3d9
PH
3258
3259/* Send permanent failure response to the command, but the code used isn't
3260always a 5xx one - see comments at the start of this function. If the original
3261rc was FAIL_DROP we drop the connection and yield 2. */
3262
ff5929e3
JH
3263if (rc == FAIL)
3264 smtp_respond(smtp_code, codelen, TRUE,
3265 user_msg ? user_msg : US"Administrative prohibition");
059ec3d9
PH
3266
3267/* Send temporary failure response to the command. Don't give any details,
3268unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
3269verb, and for a header verify when smtp_return_error_details is set.
3270
3271This conditional logic is all somewhat of a mess because of the odd
3272interactions between temp_details and return_error_details. One day it should
3273be re-implemented in a tidier fashion. */
3274
3275else
ff5929e3 3276 if (acl_temp_details && user_msg)
059ec3d9 3277 {
ff5929e3
JH
3278 if ( smtp_return_error_details
3279 && sender_verified_failed
3280 && sender_verified_failed->message
3281 )
a5bd321b 3282 smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
ff5929e3 3283
a5bd321b 3284 smtp_respond(smtp_code, codelen, TRUE, user_msg);
059ec3d9
PH
3285 }
3286 else
a5bd321b
PH
3287 smtp_respond(smtp_code, codelen, TRUE,
3288 US"Temporary local problem - please try later");
059ec3d9 3289
6ea85e9a
PH
3290/* Log the incident to the logs that are specified by log_reject_target
3291(default main, reject). This can be empty to suppress logging of rejections. If
3292the connection is not forcibly to be dropped, return 0. Otherwise, log why it
3293is closing if required and return 2. */
059ec3d9 3294
6ea85e9a 3295if (log_reject_target != 0)
887291d2 3296 {
e45a1c37 3297#ifdef SUPPORT_TLS
fc16abb4
JH
3298 uschar * tls = s_tlslog(NULL, NULL, NULL);
3299 if (!tls) tls = US"";
e45a1c37 3300#else
fc16abb4 3301 uschar * tls = US"";
e45a1c37 3302#endif
3cc3f762
JH
3303 log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0,
3304 log_reject_target, "%s%s%s %s%srejected %s%s",
fc16abb4
JH
3305 LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"",
3306 host_and_ident(TRUE),
3307 tls,
3308 sender_info,
3309 rc == FAIL ? US"" : US"temporarily ",
3310 what, log_msg);
887291d2 3311 }
059ec3d9
PH
3312
3313if (!drop) return 0;
3314
3315log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
3316 smtp_get_connection_info());
8f128379
PH
3317
3318/* Run the not-quit ACL, but without any custom messages. This should not be a
3319problem, because we get here only if some other ACL has issued "drop", and
3320in that case, *its* custom messages will have been used above. */
3321
3322smtp_notquit_exit(US"acl-drop", NULL, NULL);
059ec3d9
PH
3323return 2;
3324}
3325
3326
3327
3328
3329/*************************************************
8f128379
PH
3330* Handle SMTP exit when QUIT is not given *
3331*************************************************/
3332
3333/* This function provides a logging/statistics hook for when an SMTP connection
3334is dropped on the floor or the other end goes away. It's a global function
3335because it's called from receive.c as well as this module. As well as running
3336the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
3337response, either with a custom message from the ACL, or using a default. There
3338is one case, however, when no message is output - after "drop". In that case,
3339the ACL that obeyed "drop" has already supplied the custom message, and NULL is
3340passed to this function.
3341
3342In case things go wrong while processing this function, causing an error that
4c04137d 3343may re-enter this function, there is a recursion check.
8f128379
PH
3344
3345Arguments:
3346 reason What $smtp_notquit_reason will be set to in the ACL;
3347 if NULL, the ACL is not run
3348 code The error code to return as part of the response
3349 defaultrespond The default message if there's no user_msg
3350
3351Returns: Nothing
3352*/
3353
3354void
3355smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
3356{
3357int rc;
3358uschar *user_msg = NULL;
3359uschar *log_msg = NULL;
3360
3361/* Check for recursive acll */
3362
3363if (smtp_exit_function_called)
3364 {
3365 log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
3366 reason);
3367 return;
3368 }
3369smtp_exit_function_called = TRUE;
3370
3371/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
3372
eea0defe 3373if (acl_smtp_notquit && reason)
8f128379
PH
3374 {
3375 smtp_notquit_reason = reason;
eea0defe
JB
3376 if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
3377 &log_msg)) == ERROR)
8f128379
PH
3378 log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
3379 log_msg);
3380 }
3381
3382/* Write an SMTP response if we are expected to give one. As the default
3383responses are all internal, they should always fit in the buffer, but code a
3384warning, just in case. Note that string_vformat() still leaves a complete
3385string, even if it is incomplete. */
3386
eea0defe 3387if (code && defaultrespond)
8f128379 3388 {
eea0defe
JB
3389 if (user_msg)
3390 smtp_respond(code, 3, TRUE, user_msg);
3391 else
8f128379
PH
3392 {
3393 uschar buffer[128];
3394 va_list ap;
3395 va_start(ap, defaultrespond);
3396 if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap))
3397 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()");
925ac8e4 3398 smtp_printf("%s %s\r\n", FALSE, code, buffer);
8f128379
PH
3399 va_end(ap);
3400 }
8f128379
PH
3401 mac_smtp_fflush();
3402 }
3403}
3404
3405
3406
3407
3408/*************************************************
d7b47fd0
PH
3409* Verify HELO argument *
3410*************************************************/
3411
3412/* This function is called if helo_verify_hosts or helo_try_verify_hosts is
3413matched. It is also called from ACL processing if verify = helo is used and
3414verification was not previously tried (i.e. helo_try_verify_hosts was not
3415matched). The result of its processing is to set helo_verified and
3416helo_verify_failed. These variables should both be FALSE for this function to
3417be called.
3418
3419Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow
3420for IPv6 ::ffff: literals.
3421
3422Argument: none
3423Returns: TRUE if testing was completed;
3424 FALSE on a temporary failure
3425*/
3426
3427BOOL
3428smtp_verify_helo(void)
3429{
3430BOOL yield = TRUE;
3431
3432HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n",
3433 sender_helo_name);
3434
3435if (sender_helo_name == NULL)
3436 {
3437 HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n");
3438 }
3439
d1d5595c
PH
3440/* Deal with the case of -bs without an IP address */
3441
3442else if (sender_host_address == NULL)
3443 {
3444 HDEBUG(D_receive) debug_printf("no client IP address: assume success\n");
3445 helo_verified = TRUE;
3446 }
3447
3448/* Deal with the more common case when there is a sending IP address */
3449
d7b47fd0
PH
3450else if (sender_helo_name[0] == '[')
3451 {
3452 helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,
3453 Ustrlen(sender_host_address)) == 0;
3454
3455 #if HAVE_IPV6
3456 if (!helo_verified)
3457 {
3458 if (strncmpic(sender_host_address, US"::ffff:", 7) == 0)
3459 helo_verified = Ustrncmp(sender_helo_name + 1,
3460 sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0;
3461 }
3462 #endif
3463
3464 HDEBUG(D_receive)
3465 { if (helo_verified) debug_printf("matched host address\n"); }
3466 }
3467
3468/* Do a reverse lookup if one hasn't already given a positive or negative
3469response. If that fails, or the name doesn't match, try checking with a forward
3470lookup. */
3471
3472else
3473 {
3474 if (sender_host_name == NULL && !host_lookup_failed)
3475 yield = host_name_lookup() != DEFER;
3476
3477 /* If a host name is known, check it and all its aliases. */
3478
1705dd20
JH
3479 if (sender_host_name)
3480 if ((helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0))
d7b47fd0 3481 {
1705dd20 3482 sender_helo_dnssec = sender_host_dnssec;
d7b47fd0
PH
3483 HDEBUG(D_receive) debug_printf("matched host name\n");
3484 }
3485 else
3486 {
3487 uschar **aliases = sender_host_aliases;
1705dd20
JH
3488 while (*aliases)
3489 if ((helo_verified = strcmpic(*aliases++, sender_helo_name) == 0))
3490 {
3491 sender_helo_dnssec = sender_host_dnssec;
3492 break;
3493 }
3494
3495 HDEBUG(D_receive) if (helo_verified)
d7b47fd0 3496 debug_printf("matched alias %s\n", *(--aliases));
d7b47fd0 3497 }
d7b47fd0
PH
3498
3499 /* Final attempt: try a forward lookup of the helo name */
3500
3501 if (!helo_verified)
3502 {
3503 int rc;
3504 host_item h;
1705dd20
JH
3505 dnssec_domains d;
3506 host_item *hh;
3507
d7b47fd0
PH
3508 h.name = sender_helo_name;
3509 h.address = NULL;
3510 h.mx = MX_NONE;
3511 h.next = NULL;
1705dd20
JH
3512 d.request = US"*";
3513 d.require = US"";
3514
d7b47fd0
PH
3515 HDEBUG(D_receive) debug_printf("getting IP address for %s\n",
3516 sender_helo_name);
1705dd20
JH
3517 rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A,
3518 NULL, NULL, NULL, &d, NULL, NULL);
d7b47fd0 3519 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
1705dd20 3520 for (hh = &h; hh; hh = hh->next)
d7b47fd0
PH
3521 if (Ustrcmp(hh->address, sender_host_address) == 0)
3522 {
3523 helo_verified = TRUE;
1705dd20 3524 if (h.dnssec == DS_YES) sender_helo_dnssec = TRUE;
d7b47fd0 3525 HDEBUG(D_receive)
1705dd20
JH
3526 {
3527 debug_printf("IP address for %s matches calling address\n"
3528 "Forward DNS security status: %sverified\n",
3529 sender_helo_name, sender_helo_dnssec ? "" : "un");
3530 }
d7b47fd0
PH
3531 break;
3532 }
d7b47fd0
PH
3533 }
3534 }
3535
d1d5595c 3536if (!helo_verified) helo_verify_failed = TRUE; /* We've tried ... */
d7b47fd0
PH
3537return yield;
3538}
3539
3540
3541
3542
3543/*************************************************
4e88a19f
PH
3544* Send user response message *
3545*************************************************/
3546
3547/* This function is passed a default response code and a user message. It calls
3548smtp_message_code() to check and possibly modify the response code, and then
3549calls smtp_respond() to transmit the response. I put this into a function
3550just to avoid a lot of repetition.
3551
3552Arguments:
3553 code the response code
3554 user_msg the user message
3555
3556Returns: nothing
3557*/
3558
3559static void
3560smtp_user_msg(uschar *code, uschar *user_msg)
3561{
3562int len = 3;
4f6ae5c3 3563smtp_message_code(&code, &len, &user_msg, NULL, TRUE);
4e88a19f
PH
3564smtp_respond(code, len, TRUE, user_msg);
3565}
3566
3567
3568
b3ef41c9
JH
3569static int
3570smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss)
3571{
3572const uschar *set_id = NULL;
3573int rc, i;
3574
3575/* Run the checking code, passing the remainder of the command line as
3576data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
3577it as the only set numerical variable. The authenticator may set $auth<n>
3578and also set other numeric variables. The $auth<n> variables are preferred
3579nowadays; the numerical variables remain for backwards compatibility.
3580
3581Afterwards, have a go at expanding the set_id string, even if
3582authentication failed - for bad passwords it can be useful to log the
3583userid. On success, require set_id to expand and exist, and put it in
3584authenticated_id. Save this in permanent store, as the working store gets
3585reset at HELO, RSET, etc. */
3586
3587for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
3588expand_nmax = 0;
3589expand_nlength[0] = 0; /* $0 contains nothing */
3590
3591rc = (au->info->servercode)(au, smtp_cmd_data);
3592if (au->set_id) set_id = expand_string(au->set_id);
3593expand_nmax = -1; /* Reset numeric variables */
3594for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
3595
3596/* The value of authenticated_id is stored in the spool file and printed in
3597log lines. It must not contain binary zeros or newline characters. In
3598normal use, it never will, but when playing around or testing, this error
3599can (did) happen. To guard against this, ensure that the id contains only
3600printing characters. */
3601
3602if (set_id) set_id = string_printing(set_id);
3603
3604/* For the non-OK cases, set up additional logging data if set_id
3605is not empty. */
3606
3607if (rc != OK)
3608 set_id = set_id && *set_id
3609 ? string_sprintf(" (set_id=%s)", set_id) : US"";
3610
3611/* Switch on the result */
3612
3613switch(rc)
3614 {
3615 case OK:
3616 if (!au->set_id || set_id) /* Complete success */
3617 {
3618 if (set_id) authenticated_id = string_copy_malloc(set_id);
3619 sender_host_authenticated = au->name;
3620 authentication_failed = FALSE;
3621 authenticated_fail_id = NULL; /* Impossible to already be set? */
3622
3623 received_protocol =
3624 (sender_host_address ? protocols : protocols_local)
3625 [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)];
3626 *s = *ss = US"235 Authentication succeeded";
3627 authenticated_by = au;
3628 break;
3629 }
3630
3631 /* Authentication succeeded, but we failed to expand the set_id string.
3632 Treat this as a temporary error. */
3633
3634 auth_defer_msg = expand_string_message;
3635 /* Fall through */
3636
3637 case DEFER:
3638 if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
3639 *s = string_sprintf("435 Unable to authenticate at present%s",
3640 auth_defer_user_msg);
3641 *ss = string_sprintf("435 Unable to authenticate at present%s: %s",
3642 set_id, auth_defer_msg);