Raise smtp_cmd_buffer_size to 16384.
[exim.git] / src / src / smtp_in.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
0a49a7a4 5/* Copyright (c) University of Cambridge 1995 - 2009 */
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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"
12
13
14/* Initialize for TCP wrappers if so configured. It appears that the macro
15HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before
16including that header, and restore its value afterwards. */
17
18#ifdef USE_TCP_WRAPPERS
19
20 #if HAVE_IPV6
21 #define EXIM_HAVE_IPV6
22 #endif
23 #undef HAVE_IPV6
24 #include <tcpd.h>
25 #undef HAVE_IPV6
26 #ifdef EXIM_HAVE_IPV6
27 #define HAVE_IPV6 TRUE
28 #endif
29
30int allow_severity = LOG_INFO;
31int deny_severity = LOG_NOTICE;
5dc43717 32uschar *tcp_wrappers_name;
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33#endif
34
35
8d67ada3
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36/* Size of buffer for reading SMTP commands. We used to use 512, as defined
37by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
38commands that accept arguments, and this in particular applies to AUTH, where
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39the data can be quite long. More recently this value was 2048 in Exim;
40however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients
41such as Thunderbird will send an AUTH with an initial-response for GSSAPI.
42The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and
43we need room to handle large base64-encoded AUTHs for GSSAPI.
44*/
45
46#define smtp_cmd_buffer_size 16384
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47
48/* Size of buffer for reading SMTP incoming packets */
49
50#define in_buffer_size 8192
51
52/* Structure for SMTP command list */
53
54typedef struct {
1ba28e2b 55 const char *name;
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56 int len;
57 short int cmd;
58 short int has_arg;
59 short int is_mail_cmd;
60} smtp_cmd_list;
61
62/* Codes for identifying commands. We order them so that those that come first
63are those for which synchronization is always required. Checking this can help
64block some spam. */
65
66enum {
67 /* These commands are required to be synchronized, i.e. to be the last in a
68 block of commands when pipelining. */
69
70 HELO_CMD, EHLO_CMD, DATA_CMD, /* These are listed in the pipelining */
71 VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */
72 ETRN_CMD, /* This by analogy with TURN from the RFC */
73 STARTTLS_CMD, /* Required by the STARTTLS RFC */
74
75 /* This is a dummy to identify the non-sync commands when pipelining */
76
77 NON_SYNC_CMD_PIPELINING,
78
79 /* These commands need not be synchronized when pipelining */
80
81 MAIL_CMD, RCPT_CMD, RSET_CMD,
82
83 /* This is a dummy to identify the non-sync commands when not pipelining */
84
85 NON_SYNC_CMD_NON_PIPELINING,
86
87 /* I have been unable to find a statement about the use of pipelining
88 with AUTH, so to be on the safe side it is here, though I kind of feel
89 it should be up there with the synchronized commands. */
90
91 AUTH_CMD,
92
93 /* I'm not sure about these, but I don't think they matter. */
94
95 QUIT_CMD, HELP_CMD,
96
97 /* These are specials that don't correspond to actual commands */
98
99 EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD,
100 TOO_MANY_NONMAIL_CMD };
101
102
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103/* This is a convenience macro for adding the identity of an SMTP command
104to the circular buffer that holds a list of the last n received. */
105
106#define HAD(n) \
107 smtp_connection_had[smtp_ch_index++] = n; \
108 if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
109
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110
111/*************************************************
112* Local static variables *
113*************************************************/
114
115static auth_instance *authenticated_by;
116static BOOL auth_advertised;
117#ifdef SUPPORT_TLS
118static BOOL tls_advertised;
119#endif
120static BOOL esmtp;
121static BOOL helo_required = FALSE;
122static BOOL helo_verify = FALSE;
123static BOOL helo_seen;
124static BOOL helo_accept_junk;
125static BOOL count_nonmail;
126static BOOL pipelining_advertised;
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127static BOOL rcpt_smtp_response_same;
128static BOOL rcpt_in_progress;
059ec3d9 129static int nonmail_command_count;
8f128379 130static BOOL smtp_exit_function_called = 0;
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131static int synprot_error_count;
132static int unknown_command_count;
133static int sync_cmd_limit;
134static int smtp_write_error = 0;
135
2679d413 136static uschar *rcpt_smtp_response;
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137static uschar *smtp_data_buffer;
138static uschar *smtp_cmd_data;
139
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140/* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
141final fields of all except AUTH are forced TRUE at the start of a new message
142setup, to allow one of each between messages that is not counted as a nonmail
143command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to
144allow a new EHLO after starting up TLS.
145
146AUTH is "falsely" labelled as a mail command initially, so that it doesn't get
147counted. However, the flag is changed when AUTH is received, so that multiple
148failing AUTHs will eventually hit the limit. After a successful AUTH, another
149AUTH is already forbidden. After a TLS session is started, AUTH's flag is again
150forced TRUE, to allow for the re-authentication that can happen at that point.
151
152QUIT is also "falsely" labelled as a mail command so that it doesn't up the
153count of non-mail commands and possibly provoke an error. */
154
155static smtp_cmd_list cmd_list[] = {
156 { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */
157 { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE },
158 { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE },
159 { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
160 #ifdef SUPPORT_TLS
161 { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
162 #endif
163
164/* If you change anything above here, also fix the definitions below. */
165
166 { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE },
167 { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE },
168 { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE },
169 { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE },
170 { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE },
171 { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE },
172 { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE },
173 { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE },
174 { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE }
175};
176
177static smtp_cmd_list *cmd_list_end =
178 cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list);
179
180#define CMD_LIST_RSET 0
181#define CMD_LIST_HELO 1
182#define CMD_LIST_EHLO 2
183#define CMD_LIST_AUTH 3
184#define CMD_LIST_STARTTLS 4
185
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186/* This list of names is used for performing the smtp_no_mail logging action.
187It must be kept in step with the SCH_xxx enumerations. */
188
189static uschar *smtp_names[] =
190 {
191 US"NONE", US"AUTH", US"DATA", US"EHLO", US"ETRN", US"EXPN", US"HELO",
192 US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET", US"STARTTLS",
193 US"VRFY" };
194
059ec3d9 195static uschar *protocols[] = {
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196 US"local-smtp", /* HELO */
197 US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
198 US"local-esmtp", /* EHLO */
199 US"local-esmtps", /* EHLO->STARTTLS->EHLO */
200 US"local-esmtpa", /* EHLO->AUTH */
201 US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
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202 };
203
204#define pnormal 0
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205#define pextend 2
206#define pcrpted 1 /* added to pextend or pnormal */
207#define pauthed 2 /* added to pextend */
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208#define pnlocal 6 /* offset to remove "local" */
209
210/* When reading SMTP from a remote host, we have to use our own versions of the
211C input-reading functions, in order to be able to flush the SMTP output only
212when about to read more data from the socket. This is the only way to get
213optimal performance when the client is using pipelining. Flushing for every
214command causes a separate packet and reply packet each time; saving all the
215responses up (when pipelining) combines them into one packet and one response.
216
217For simplicity, these functions are used for *all* SMTP input, not only when
218receiving over a socket. However, after setting up a secure socket (SSL), input
219is read via the OpenSSL library, and another set of functions is used instead
220(see tls.c).
221
222These functions are set in the receive_getc etc. variables and called with the
223same interface as the C functions. However, since there can only ever be
224one incoming SMTP call, we just use a single buffer and flags. There is no need
225to implement a complicated private FILE-like structure.*/
226
227static uschar *smtp_inbuffer;
228static uschar *smtp_inptr;
229static uschar *smtp_inend;
230static int smtp_had_eof;
231static int smtp_had_error;
232
233
234/*************************************************
235* SMTP version of getc() *
236*************************************************/
237
238/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
239it flushes the output, and refills the buffer, with a timeout. The signal
240handler is set appropriately by the calling function. This function is not used
241after a connection has negotated itself into an TLS/SSL state.
242
243Arguments: none
244Returns: the next character or EOF
245*/
246
247int
248smtp_getc(void)
249{
250if (smtp_inptr >= smtp_inend)
251 {
252 int rc, save_errno;
253 fflush(smtp_out);
254 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
255 rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size);
256 save_errno = errno;
257 alarm(0);
258 if (rc <= 0)
259 {
260 /* Must put the error text in fixed store, because this might be during
261 header reading, where it releases unused store above the header. */
262 if (rc < 0)
263 {
264 smtp_had_error = save_errno;
265 smtp_read_error = string_copy_malloc(
266 string_sprintf(" (error: %s)", strerror(save_errno)));
267 }
268 else smtp_had_eof = 1;
269 return EOF;
270 }
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271#ifndef DISABLE_DKIM
272 dkim_exim_verify_feed(smtp_inbuffer, rc);
273#endif
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274 smtp_inend = smtp_inbuffer + rc;
275 smtp_inptr = smtp_inbuffer;
276 }
277return *smtp_inptr++;
278}
279
280
281
282/*************************************************
283* SMTP version of ungetc() *
284*************************************************/
285
286/* Puts a character back in the input buffer. Only ever
287called once.
288
289Arguments:
290 ch the character
291
292Returns: the character
293*/
294
295int
296smtp_ungetc(int ch)
297{
298*(--smtp_inptr) = ch;
299return ch;
300}
301
302
303
304
305/*************************************************
306* SMTP version of feof() *
307*************************************************/
308
309/* Tests for a previous EOF
310
311Arguments: none
312Returns: non-zero if the eof flag is set
313*/
314
315int
316smtp_feof(void)
317{
318return smtp_had_eof;
319}
320
321
322
323
324/*************************************************
325* SMTP version of ferror() *
326*************************************************/
327
328/* Tests for a previous read error, and returns with errno
329restored to what it was when the error was detected.
330
331Arguments: none
332Returns: non-zero if the error flag is set
333*/
334
335int
336smtp_ferror(void)
337{
338errno = smtp_had_error;
339return smtp_had_error;
340}
341
342
343
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344/*************************************************
345* Test for characters in the SMTP buffer *
346*************************************************/
347
348/* Used at the end of a message
349
350Arguments: none
351Returns: TRUE/FALSE
352*/
353
354BOOL
355smtp_buffered(void)
356{
357return smtp_inptr < smtp_inend;
358}
359
360
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361
362/*************************************************
363* Write formatted string to SMTP channel *
364*************************************************/
365
366/* This is a separate function so that we don't have to repeat everything for
367TLS support or debugging. It is global so that the daemon and the
368authentication functions can use it. It does not return any error indication,
369because major problems such as dropped connections won't show up till an output
370flush for non-TLS connections. The smtp_fflush() function is available for
371checking that: for convenience, TLS output errors are remembered here so that
372they are also picked up later by smtp_fflush().
373
374Arguments:
375 format format string
376 ... optional arguments
377
378Returns: nothing
379*/
380
381void
1ba28e2b 382smtp_printf(const char *format, ...)
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383{
384va_list ap;
385
ce552449
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386va_start(ap, format);
387smtp_vprintf(format, ap);
388va_end(ap);
389}
390
391/* This is split off so that verify.c:respond_printf() can, in effect, call
392smtp_printf(), bearing in mind that in C a vararg function can't directly
fb08281f 393call another vararg function, only a function which accepts a va_list. */
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394
395void
1ba28e2b 396smtp_vprintf(const char *format, va_list ap)
ce552449 397{
fb08281f
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398BOOL yield;
399
400yield = string_vformat(big_buffer, big_buffer_size, format, ap);
ce552449 401
059ec3d9
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402DEBUG(D_receive)
403 {
fb08281f
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404 void *reset_point = store_get(0);
405 uschar *msg_copy, *cr, *end;
406 msg_copy = string_copy(big_buffer);
407 end = msg_copy + Ustrlen(msg_copy);
408 while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
409 memmove(cr, cr + 1, (end--) - cr);
410 debug_printf("SMTP>> %s", msg_copy);
411 store_reset(reset_point);
059ec3d9
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412 }
413
fb08281f 414if (!yield)
2679d413
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415 {
416 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
417 smtp_closedown(US"Unexpected error");
418 exim_exit(EXIT_FAILURE);
419 }
2679d413
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420
421/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
422have had the same. Note: this code is also present in smtp_respond(). It would
423be tidier to have it only in one place, but when it was added, it was easier to
424do it that way, so as not to have to mess with the code for the RCPT command,
425which sometimes uses smtp_printf() and sometimes smtp_respond(). */
426
427if (rcpt_in_progress)
428 {
429 if (rcpt_smtp_response == NULL)
430 rcpt_smtp_response = string_copy(big_buffer);
431 else if (rcpt_smtp_response_same &&
432 Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
433 rcpt_smtp_response_same = FALSE;
434 rcpt_in_progress = FALSE;
435 }
059ec3d9 436
2679d413 437/* Now write the string */
059ec3d9
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438
439#ifdef SUPPORT_TLS
440if (tls_active >= 0)
441 {
059ec3d9
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442 if (tls_write(big_buffer, Ustrlen(big_buffer)) < 0) smtp_write_error = -1;
443 }
444else
445#endif
446
2679d413 447if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1;
059ec3d9
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448}
449
450
451
452/*************************************************
453* Flush SMTP out and check for error *
454*************************************************/
455
456/* This function isn't currently used within Exim (it detects errors when it
457tries to read the next SMTP input), but is available for use in local_scan().
458For non-TLS connections, it flushes the output and checks for errors. For
459TLS-connections, it checks for a previously-detected TLS write error.
460
461Arguments: none
462Returns: 0 for no error; -1 after an error
463*/
464
465int
466smtp_fflush(void)
467{
468if (tls_active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
469return smtp_write_error;
470}
471
472
473
474/*************************************************
475* SMTP command read timeout *
476*************************************************/
477
478/* Signal handler for timing out incoming SMTP commands. This attempts to
479finish off tidily.
480
481Argument: signal number (SIGALRM)
482Returns: nothing
483*/
484
485static void
486command_timeout_handler(int sig)
487{
488sig = sig; /* Keep picky compilers happy */
489log_write(L_lost_incoming_connection,
490 LOG_MAIN, "SMTP command timeout on%s connection from %s",
491 (tls_active >= 0)? " TLS" : "",
492 host_and_ident(FALSE));
493if (smtp_batched_input)
494 moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
8f128379
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495smtp_notquit_exit(US"command-timeout", US"421",
496 US"%s: SMTP command timeout - closing connection", smtp_active_hostname);
059ec3d9
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497exim_exit(EXIT_FAILURE);
498}
499
500
501
502/*************************************************
503* SIGTERM received *
504*************************************************/
505
506/* Signal handler for handling SIGTERM. Again, try to finish tidily.
507
508Argument: signal number (SIGTERM)
509Returns: nothing
510*/
511
512static void
513command_sigterm_handler(int sig)
514{
515sig = sig; /* Keep picky compilers happy */
516log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
517if (smtp_batched_input)
518 moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
8f128379
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519smtp_notquit_exit(US"signal-exit", US"421",
520 US"%s: Service not available - closing connection", smtp_active_hostname);
059ec3d9
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521exim_exit(EXIT_FAILURE);
522}
523
524
525
a14e5636 526
059ec3d9
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527/*************************************************
528* Read one command line *
529*************************************************/
530
531/* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
532There are sites that don't do this, and in any case internal SMTP probably
533should check only for LF. Consequently, we check here for LF only. The line
534ends up with [CR]LF removed from its end. If we get an overlong line, treat as
3ee512ff
PH
535an unknown command. The command is read into the global smtp_cmd_buffer so that
536it is available via $smtp_command.
059ec3d9
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537
538The character reading routine sets up a timeout for each block actually read
539from the input (which may contain more than one command). We set up a special
540signal handler that closes down the session on a timeout. Control does not
541return when it runs.
542
543Arguments:
544 check_sync if TRUE, check synchronization rules if global option is TRUE
545
546Returns: a code identifying the command (enumerated above)
547*/
548
549static int
550smtp_read_command(BOOL check_sync)
551{
552int c;
553int ptr = 0;
554smtp_cmd_list *p;
555BOOL hadnull = FALSE;
556
557os_non_restarting_signal(SIGALRM, command_timeout_handler);
558
559while ((c = (receive_getc)()) != '\n' && c != EOF)
560 {
3ee512ff 561 if (ptr >= smtp_cmd_buffer_size)
059ec3d9
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562 {
563 os_non_restarting_signal(SIGALRM, sigalrm_handler);
564 return OTHER_CMD;
565 }
566 if (c == 0)
567 {
568 hadnull = TRUE;
569 c = '?';
570 }
3ee512ff 571 smtp_cmd_buffer[ptr++] = c;
059ec3d9
PH
572 }
573
574receive_linecount++; /* For BSMTP errors */
575os_non_restarting_signal(SIGALRM, sigalrm_handler);
576
577/* If hit end of file, return pseudo EOF command. Whether we have a
578part-line already read doesn't matter, since this is an error state. */
579
580if (c == EOF) return EOF_CMD;
581
582/* Remove any CR and white space at the end of the line, and terminate the
583string. */
584
3ee512ff
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585while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
586smtp_cmd_buffer[ptr] = 0;
059ec3d9 587
3ee512ff 588DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
059ec3d9
PH
589
590/* NULLs are not allowed in SMTP commands */
591
592if (hadnull) return BADCHAR_CMD;
593
594/* Scan command list and return identity, having set the data pointer
595to the start of the actual data characters. Check for SMTP synchronization
596if required. */
597
598for (p = cmd_list; p < cmd_list_end; p++)
599 {
084efe8d
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600 if (strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0 &&
601 (smtp_cmd_buffer[p->len-1] == ':' || /* "mail from:" or "rcpt to:" */
602 smtp_cmd_buffer[p->len] == 0 ||
603 smtp_cmd_buffer[p->len] == ' '))
059ec3d9
PH
604 {
605 if (smtp_inptr < smtp_inend && /* Outstanding input */
606 p->cmd < sync_cmd_limit && /* Command should sync */
607 check_sync && /* Local flag set */
608 smtp_enforce_sync && /* Global flag set */
609 sender_host_address != NULL && /* Not local input */
610 !sender_host_notsocket) /* Really is a socket */
611 return BADSYN_CMD;
612
ca86f471
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613 /* The variables $smtp_command and $smtp_command_argument point into the
614 unmodified input buffer. A copy of the latter is taken for actual
615 processing, so that it can be chopped up into separate parts if necessary,
616 for example, when processing a MAIL command options such as SIZE that can
617 follow the sender address. */
059ec3d9 618
3ee512ff 619 smtp_cmd_argument = smtp_cmd_buffer + p->len;
ca86f471
PH
620 while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
621 Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
622 smtp_cmd_data = smtp_data_buffer;
059ec3d9
PH
623
624 /* Count non-mail commands from those hosts that are controlled in this
625 way. The default is all hosts. We don't waste effort checking the list
626 until we get a non-mail command, but then cache the result to save checking
627 again. If there's a DEFER while checking the host, assume it's in the list.
628
629 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
630 start of each incoming message by fiddling with the value in the table. */
631
632 if (!p->is_mail_cmd)
633 {
634 if (count_nonmail == TRUE_UNSET) count_nonmail =
635 verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL;
636 if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail)
637 return TOO_MANY_NONMAIL_CMD;
638 }
639
ca86f471
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640 /* If there is data for a command that does not expect it, generate the
641 error here. */
059ec3d9 642
ca86f471 643 return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
059ec3d9
PH
644 }
645 }
646
647/* Enforce synchronization for unknown commands */
648
649if (smtp_inptr < smtp_inend && /* Outstanding input */
650 check_sync && /* Local flag set */
651 smtp_enforce_sync && /* Global flag set */
652 sender_host_address != NULL && /* Not local input */
653 !sender_host_notsocket) /* Really is a socket */
654 return BADSYN_CMD;
655
656return OTHER_CMD;
657}
658
659
660
661/*************************************************
a14e5636
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662* Recheck synchronization *
663*************************************************/
664
665/* Synchronization checks can never be perfect because a packet may be on its
666way but not arrived when the check is done. Such checks can in any case only be
667done when TLS is not in use. Normally, the checks happen when commands are
668read: Exim ensures that there is no more input in the input buffer. In normal
669cases, the response to the command will be fast, and there is no further check.
670
671However, for some commands an ACL is run, and that can include delays. In those
672cases, it is useful to do another check on the input just before sending the
673response. This also applies at the start of a connection. This function does
674that check by means of the select() function, as long as the facility is not
675disabled or inappropriate. A failure of select() is ignored.
676
677When there is unwanted input, we read it so that it appears in the log of the
678error.
679
680Arguments: none
681Returns: TRUE if all is well; FALSE if there is input pending
682*/
683
684static BOOL
685check_sync(void)
686{
687int fd, rc;
688fd_set fds;
689struct timeval tzero;
690
691if (!smtp_enforce_sync || sender_host_address == NULL ||
692 sender_host_notsocket || tls_active >= 0)
693 return TRUE;
694
695fd = fileno(smtp_in);
696FD_ZERO(&fds);
697FD_SET(fd, &fds);
698tzero.tv_sec = 0;
699tzero.tv_usec = 0;
700rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
701
702if (rc <= 0) return TRUE; /* Not ready to read */
703rc = smtp_getc();
704if (rc < 0) return TRUE; /* End of file or error */
705
706smtp_ungetc(rc);
707rc = smtp_inend - smtp_inptr;
708if (rc > 150) rc = 150;
709smtp_inptr[rc] = 0;
710return FALSE;
711}
712
713
714
715/*************************************************
059ec3d9
PH
716* Forced closedown of call *
717*************************************************/
718
719/* This function is called from log.c when Exim is dying because of a serious
720disaster, and also from some other places. If an incoming non-batched SMTP
721channel is open, it swallows the rest of the incoming message if in the DATA
722phase, sends the reply string, and gives an error to all subsequent commands
723except QUIT. The existence of an SMTP call is detected by the non-NULLness of
724smtp_in.
725
8f128379
PH
726Arguments:
727 message SMTP reply string to send, excluding the code
728
059ec3d9
PH
729Returns: nothing
730*/
731
732void
733smtp_closedown(uschar *message)
734{
735if (smtp_in == NULL || smtp_batched_input) return;
736receive_swallow_smtp();
737smtp_printf("421 %s\r\n", message);
738
739for (;;)
740 {
741 switch(smtp_read_command(FALSE))
742 {
743 case EOF_CMD:
744 return;
745
746 case QUIT_CMD:
747 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
748 mac_smtp_fflush();
749 return;
750
751 case RSET_CMD:
752 smtp_printf("250 Reset OK\r\n");
753 break;
754
755 default:
756 smtp_printf("421 %s\r\n", message);
757 break;
758 }
759 }
760}
761
762
763
764
765/*************************************************
766* Set up connection info for logging *
767*************************************************/
768
769/* This function is called when logging information about an SMTP connection.
770It sets up appropriate source information, depending on the type of connection.
dac79d3e
PH
771If sender_fullhost is NULL, we are at a very early stage of the connection;
772just use the IP address.
059ec3d9
PH
773
774Argument: none
775Returns: a string describing the connection
776*/
777
778uschar *
779smtp_get_connection_info(void)
780{
dac79d3e
PH
781uschar *hostname = (sender_fullhost == NULL)?
782 sender_host_address : sender_fullhost;
783
059ec3d9 784if (host_checking)
dac79d3e 785 return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
786
787if (sender_host_unknown || sender_host_notsocket)
788 return string_sprintf("SMTP connection from %s", sender_ident);
789
790if (is_inetd)
dac79d3e 791 return string_sprintf("SMTP connection from %s (via inetd)", hostname);
059ec3d9
PH
792
793if ((log_extra_selector & LX_incoming_interface) != 0 &&
794 interface_address != NULL)
dac79d3e 795 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
059ec3d9
PH
796 interface_address, interface_port);
797
dac79d3e 798return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
799}
800
801
802
803/*************************************************
b4ed4da0
PH
804* Log lack of MAIL if so configured *
805*************************************************/
806
807/* This function is called when an SMTP session ends. If the log selector
808smtp_no_mail is set, write a log line giving some details of what has happened
809in the SMTP session.
810
811Arguments: none
812Returns: nothing
813*/
814
815void
816smtp_log_no_mail(void)
817{
818int size, ptr, i;
819uschar *s, *sep;
820
821if (smtp_mailcmd_count > 0 || (log_extra_selector & LX_smtp_no_mail) == 0)
822 return;
823
824s = NULL;
825size = ptr = 0;
826
827if (sender_host_authenticated != NULL)
828 {
829 s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated);
830 if (authenticated_id != NULL)
831 s = string_append(s, &size, &ptr, 2, US":", authenticated_id);
832 }
833
834#ifdef SUPPORT_TLS
835if ((log_extra_selector & LX_tls_cipher) != 0 && tls_cipher != NULL)
836 s = string_append(s, &size, &ptr, 2, US" X=", tls_cipher);
837if ((log_extra_selector & LX_tls_certificate_verified) != 0 &&
838 tls_cipher != NULL)
839 s = string_append(s, &size, &ptr, 2, US" CV=",
840 tls_certificate_verified? "yes":"no");
841if ((log_extra_selector & LX_tls_peerdn) != 0 && tls_peerdn != NULL)
48ed62d9
PH
842 s = string_append(s, &size, &ptr, 3, US" DN=\"",
843 string_printing(tls_peerdn), US"\"");
b4ed4da0
PH
844#endif
845
846sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)?
847 US" C=..." : US" C=";
848for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
849 {
850 if (smtp_connection_had[i] != SCH_NONE)
851 {
852 s = string_append(s, &size, &ptr, 2, sep,
853 smtp_names[smtp_connection_had[i]]);
854 sep = US",";
855 }
856 }
857
858for (i = 0; i < smtp_ch_index; i++)
859 {
860 s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]);
861 sep = US",";
862 }
863
864if (s != NULL) s[ptr] = 0; else s = US"";
865log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s",
866 host_and_ident(FALSE),
867 readconf_printtime(time(NULL) - smtp_connection_start), s);
868}
869
870
871
872/*************************************************
059ec3d9
PH
873* Check HELO line and set sender_helo_name *
874*************************************************/
875
876/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
877the domain name of the sending host, or an ip literal in square brackets. The
878arrgument is placed in sender_helo_name, which is in malloc store, because it
879must persist over multiple incoming messages. If helo_accept_junk is set, this
880host is permitted to send any old junk (needed for some broken hosts).
881Otherwise, helo_allow_chars can be used for rogue characters in general
882(typically people want to let in underscores).
883
884Argument:
885 s the data portion of the line (already past any white space)
886
887Returns: TRUE or FALSE
888*/
889
890static BOOL
891check_helo(uschar *s)
892{
893uschar *start = s;
894uschar *end = s + Ustrlen(s);
895BOOL yield = helo_accept_junk;
896
897/* Discard any previous helo name */
898
899if (sender_helo_name != NULL)
900 {
901 store_free(sender_helo_name);
902 sender_helo_name = NULL;
903 }
904
905/* Skip tests if junk is permitted. */
906
907if (!yield)
908 {
909 /* Allow the new standard form for IPv6 address literals, namely,
910 [IPv6:....], and because someone is bound to use it, allow an equivalent
911 IPv4 form. Allow plain addresses as well. */
912
913 if (*s == '[')
914 {
915 if (end[-1] == ']')
916 {
917 end[-1] = 0;
918 if (strncmpic(s, US"[IPv6:", 6) == 0)
919 yield = (string_is_ip_address(s+6, NULL) == 6);
920 else if (strncmpic(s, US"[IPv4:", 6) == 0)
921 yield = (string_is_ip_address(s+6, NULL) == 4);
922 else
923 yield = (string_is_ip_address(s+1, NULL) != 0);
924 end[-1] = ']';
925 }
926 }
927
928 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
929 that have been configured (usually underscore - sigh). */
930
931 else if (*s != 0)
932 {
933 yield = TRUE;
934 while (*s != 0)
935 {
936 if (!isalnum(*s) && *s != '.' && *s != '-' &&
937 Ustrchr(helo_allow_chars, *s) == NULL)
938 {
939 yield = FALSE;
940 break;
941 }
942 s++;
943 }
944 }
945 }
946
947/* Save argument if OK */
948
949if (yield) sender_helo_name = string_copy_malloc(start);
950return yield;
951}
952
953
954
955
956
957/*************************************************
958* Extract SMTP command option *
959*************************************************/
960
ca86f471 961/* This function picks the next option setting off the end of smtp_cmd_data. It
059ec3d9
PH
962is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
963things that can appear there.
964
965Arguments:
966 name point this at the name
967 value point this at the data string
968
969Returns: TRUE if found an option
970*/
971
972static BOOL
973extract_option(uschar **name, uschar **value)
974{
975uschar *n;
ca86f471 976uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
059ec3d9
PH
977while (isspace(*v)) v--;
978v[1] = 0;
979
ca86f471 980while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) v--;
059ec3d9
PH
981if (*v != '=') return FALSE;
982
983n = v;
984while(isalpha(n[-1])) n--;
985
986if (n[-1] != ' ') return FALSE;
987
988n[-1] = 0;
989*name = n;
990*v++ = 0;
991*value = v;
992return TRUE;
993}
994
995
996
997
998
059ec3d9
PH
999/*************************************************
1000* Reset for new message *
1001*************************************************/
1002
1003/* This function is called whenever the SMTP session is reset from
1004within either of the setup functions.
1005
1006Argument: the stacking pool storage reset point
1007Returns: nothing
1008*/
1009
1010static void
1011smtp_reset(void *reset_point)
1012{
059ec3d9
PH
1013store_reset(reset_point);
1014recipients_list = NULL;
1015rcpt_count = rcpt_defer_count = rcpt_fail_count =
1016 raw_recipients_count = recipients_count = recipients_list_max = 0;
2e0c1448 1017message_linecount = 0;
059ec3d9 1018message_size = -1;
71fafd95 1019acl_added_headers = NULL;
059ec3d9 1020queue_only_policy = FALSE;
2679d413
PH
1021rcpt_smtp_response = NULL;
1022rcpt_smtp_response_same = TRUE;
1023rcpt_in_progress = FALSE;
69358f02 1024deliver_freeze = FALSE; /* Can be set by ACL */
6a3f1455 1025freeze_tell = freeze_tell_config; /* Can be set by ACL */
29aba418 1026fake_response = OK; /* Can be set by ACL */
6951ac6c 1027#ifdef WITH_CONTENT_SCAN
8523533c
TK
1028no_mbox_unspool = FALSE; /* Can be set by ACL */
1029#endif
69358f02 1030submission_mode = FALSE; /* Can be set by ACL */
8800895a 1031suppress_local_fixups = FALSE; /* Can be set by ACL */
69358f02
PH
1032active_local_from_check = local_from_check; /* Can be set by ACL */
1033active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
059ec3d9 1034sender_address = NULL;
2fe1a124 1035submission_name = NULL; /* Can be set by ACL */
059ec3d9
PH
1036raw_sender = NULL; /* After SMTP rewrite, before qualifying */
1037sender_address_unrewritten = NULL; /* Set only after verify rewrite */
1038sender_verified_list = NULL; /* No senders verified */
1039memset(sender_address_cache, 0, sizeof(sender_address_cache));
1040memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
1041authenticated_sender = NULL;
8523533c
TK
1042#ifdef EXPERIMENTAL_BRIGHTMAIL
1043bmi_run = 0;
1044bmi_verdicts = NULL;
1045#endif
80a47a2c 1046#ifndef DISABLE_DKIM
9e5d6b55 1047dkim_signers = NULL;
80a47a2c
TK
1048dkim_disable_verify = FALSE;
1049dkim_collect_input = FALSE;
f7572e5a 1050#endif
8523533c
TK
1051#ifdef EXPERIMENTAL_SPF
1052spf_header_comment = NULL;
1053spf_received = NULL;
8e669ac1 1054spf_result = NULL;
8523533c
TK
1055spf_smtp_comment = NULL;
1056#endif
059ec3d9
PH
1057body_linecount = body_zerocount = 0;
1058
870f6ba8
TF
1059sender_rate = sender_rate_limit = sender_rate_period = NULL;
1060ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
1061 /* Note that ratelimiters_conn persists across resets. */
1062
38a0a95f 1063/* Reset message ACL variables */
47ca6d6c 1064
38a0a95f 1065acl_var_m = NULL;
059ec3d9
PH
1066
1067/* The message body variables use malloc store. They may be set if this is
1068not the first message in an SMTP session and the previous message caused them
1069to be referenced in an ACL. */
1070
1071if (message_body != NULL)
1072 {
1073 store_free(message_body);
1074 message_body = NULL;
1075 }
1076
1077if (message_body_end != NULL)
1078 {
1079 store_free(message_body_end);
1080 message_body_end = NULL;
1081 }
1082
1083/* Warning log messages are also saved in malloc store. They are saved to avoid
1084repetition in the same message, but it seems right to repeat them for different
4e88a19f 1085messages. */
059ec3d9
PH
1086
1087while (acl_warn_logged != NULL)
1088 {
1089 string_item *this = acl_warn_logged;
1090 acl_warn_logged = acl_warn_logged->next;
1091 store_free(this);
1092 }
1093}
1094
1095
1096
1097
1098
1099/*************************************************
1100* Initialize for incoming batched SMTP message *
1101*************************************************/
1102
1103/* This function is called from smtp_setup_msg() in the case when
1104smtp_batched_input is true. This happens when -bS is used to pass a whole batch
1105of messages in one file with SMTP commands between them. All errors must be
1106reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
1107relevant. After an error on a sender, or an invalid recipient, the remainder
1108of the message is skipped. The value of received_protocol is already set.
1109
1110Argument: none
1111Returns: > 0 message successfully started (reached DATA)
1112 = 0 QUIT read or end of file reached
1113 < 0 should not occur
1114*/
1115
1116static int
1117smtp_setup_batch_msg(void)
1118{
1119int done = 0;
1120void *reset_point = store_get(0);
1121
1122/* Save the line count at the start of each transaction - single commands
1123like HELO and RSET count as whole transactions. */
1124
1125bsmtp_transaction_linecount = receive_linecount;
1126
1127if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
1128
1129smtp_reset(reset_point); /* Reset for start of message */
1130
1131/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
1132value. The values are 2 larger than the required yield of the function. */
1133
1134while (done <= 0)
1135 {
1136 uschar *errmess;
1137 uschar *recipient = NULL;
1138 int start, end, sender_domain, recipient_domain;
1139
1140 switch(smtp_read_command(FALSE))
1141 {
1142 /* The HELO/EHLO commands set sender_address_helo if they have
1143 valid data; otherwise they are ignored, except that they do
1144 a reset of the state. */
1145
1146 case HELO_CMD:
1147 case EHLO_CMD:
1148
ca86f471 1149 check_helo(smtp_cmd_data);
059ec3d9
PH
1150 /* Fall through */
1151
1152 case RSET_CMD:
1153 smtp_reset(reset_point);
1154 bsmtp_transaction_linecount = receive_linecount;
1155 break;
1156
1157
1158 /* The MAIL FROM command requires an address as an operand. All we
1159 do here is to parse it for syntactic correctness. The form "<>" is
1160 a special case which converts into an empty string. The start/end
1161 pointers in the original are not used further for this address, as
1162 it is the canonical extracted address which is all that is kept. */
1163
1164 case MAIL_CMD:
1165 if (sender_address != NULL)
1166 /* The function moan_smtp_batch() does not return. */
3ee512ff 1167 moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
059ec3d9 1168
ca86f471 1169 if (smtp_cmd_data[0] == 0)
059ec3d9 1170 /* The function moan_smtp_batch() does not return. */
3ee512ff 1171 moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
059ec3d9
PH
1172
1173 /* Reset to start of message */
1174
1175 smtp_reset(reset_point);
1176
1177 /* Apply SMTP rewrite */
1178
1179 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
1180 rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
1181 US"", global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
1182
1183 /* Extract the address; the TRUE flag allows <> as valid */
1184
1185 raw_sender =
1186 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
1187 TRUE);
1188
1189 if (raw_sender == NULL)
1190 /* The function moan_smtp_batch() does not return. */
3ee512ff 1191 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
1192
1193 sender_address = string_copy(raw_sender);
1194
1195 /* Qualify unqualified sender addresses if permitted to do so. */
1196
1197 if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@')
1198 {
1199 if (allow_unqualified_sender)
1200 {
1201 sender_address = rewrite_address_qualify(sender_address, FALSE);
1202 DEBUG(D_receive) debug_printf("unqualified address %s accepted "
1203 "and rewritten\n", raw_sender);
1204 }
1205 /* The function moan_smtp_batch() does not return. */
3ee512ff 1206 else moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
059ec3d9
PH
1207 "a domain");
1208 }
1209 break;
1210
1211
1212 /* The RCPT TO command requires an address as an operand. All we do
1213 here is to parse it for syntactic correctness. There may be any number
1214 of RCPT TO commands, specifying multiple senders. We build them all into
1215 a data structure that is in argc/argv format. The start/end values
1216 given by parse_extract_address are not used, as we keep only the
1217 extracted address. */
1218
1219 case RCPT_CMD:
1220 if (sender_address == NULL)
1221 /* The function moan_smtp_batch() does not return. */
3ee512ff 1222 moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
059ec3d9 1223
ca86f471 1224 if (smtp_cmd_data[0] == 0)
059ec3d9 1225 /* The function moan_smtp_batch() does not return. */
3ee512ff 1226 moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand");
059ec3d9
PH
1227
1228 /* Check maximum number allowed */
1229
1230 if (recipients_max > 0 && recipients_count + 1 > recipients_max)
1231 /* The function moan_smtp_batch() does not return. */
3ee512ff 1232 moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
059ec3d9
PH
1233 recipients_max_reject? "552": "452");
1234
1235 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
1236 recipient address */
1237
1238 recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
1239 rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
1240 global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
1241
1242 /* rfc821_domains = TRUE; << no longer needed */
1243 recipient = parse_extract_address(recipient, &errmess, &start, &end,
1244 &recipient_domain, FALSE);
1245 /* rfc821_domains = FALSE; << no longer needed */
1246
1247 if (recipient == NULL)
1248 /* The function moan_smtp_batch() does not return. */
3ee512ff 1249 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
1250
1251 /* If the recipient address is unqualified, qualify it if permitted. Then
1252 add it to the list of recipients. */
1253
1254 if (recipient_domain == 0)
1255 {
1256 if (allow_unqualified_recipient)
1257 {
1258 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
1259 recipient);
1260 recipient = rewrite_address_qualify(recipient, TRUE);
1261 }
1262 /* The function moan_smtp_batch() does not return. */
3ee512ff 1263 else moan_smtp_batch(smtp_cmd_buffer, "501 recipient address must contain "
059ec3d9
PH
1264 "a domain");
1265 }
1266 receive_add_recipient(recipient, -1);
1267 break;
1268
1269
1270 /* The DATA command is legal only if it follows successful MAIL FROM
1271 and RCPT TO commands. This function is complete when a valid DATA
1272 command is encountered. */
1273
1274 case DATA_CMD:
1275 if (sender_address == NULL || recipients_count <= 0)
1276 {
1277 /* The function moan_smtp_batch() does not return. */
1278 if (sender_address == NULL)
3ee512ff 1279 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
1280 "503 MAIL FROM:<sender> command must precede DATA");
1281 else
3ee512ff 1282 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
1283 "503 RCPT TO:<recipient> must precede DATA");
1284 }
1285 else
1286 {
1287 done = 3; /* DATA successfully achieved */
1288 message_ended = END_NOTENDED; /* Indicate in middle of message */
1289 }
1290 break;
1291
1292
1293 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
1294
1295 case VRFY_CMD:
1296 case EXPN_CMD:
1297 case HELP_CMD:
1298 case NOOP_CMD:
1299 case ETRN_CMD:
1300 bsmtp_transaction_linecount = receive_linecount;
1301 break;
1302
1303
1304 case EOF_CMD:
1305 case QUIT_CMD:
1306 done = 2;
1307 break;
1308
1309
1310 case BADARG_CMD:
1311 /* The function moan_smtp_batch() does not return. */
3ee512ff 1312 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
059ec3d9
PH
1313 break;
1314
1315
1316 case BADCHAR_CMD:
1317 /* The function moan_smtp_batch() does not return. */
3ee512ff 1318 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
059ec3d9
PH
1319 break;
1320
1321
1322 default:
1323 /* The function moan_smtp_batch() does not return. */
3ee512ff 1324 moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
059ec3d9
PH
1325 break;
1326 }
1327 }
1328
1329return done - 2; /* Convert yield values */
1330}
1331
1332
1333
1334
1335/*************************************************
1336* Start an SMTP session *
1337*************************************************/
1338
1339/* This function is called at the start of an SMTP session. Thereafter,
1340smtp_setup_msg() is called to initiate each separate message. This
1341function does host-specific testing, and outputs the banner line.
1342
1343Arguments: none
1344Returns: FALSE if the session can not continue; something has
1345 gone wrong, or the connection to the host is blocked
1346*/
1347
1348BOOL
1349smtp_start_session(void)
1350{
1351int size = 256;
4e88a19f
PH
1352int ptr, esclen;
1353uschar *user_msg, *log_msg;
1354uschar *code, *esc;
059ec3d9
PH
1355uschar *p, *s, *ss;
1356
b4ed4da0
PH
1357smtp_connection_start = time(NULL);
1358for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
1359 smtp_connection_had[smtp_ch_index] = SCH_NONE;
1360smtp_ch_index = 0;
1361
00f00ca5
PH
1362/* Default values for certain variables */
1363
059ec3d9 1364helo_seen = esmtp = helo_accept_junk = FALSE;
b4ed4da0 1365smtp_mailcmd_count = 0;
059ec3d9
PH
1366count_nonmail = TRUE_UNSET;
1367synprot_error_count = unknown_command_count = nonmail_command_count = 0;
1368smtp_delay_mail = smtp_rlm_base;
1369auth_advertised = FALSE;
1370pipelining_advertised = FALSE;
cf8b11a5 1371pipelining_enable = TRUE;
059ec3d9 1372sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
8f128379 1373smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
059ec3d9
PH
1374
1375memset(sender_host_cache, 0, sizeof(sender_host_cache));
1376
33d73e3b
PH
1377/* If receiving by -bs from a trusted user, or testing with -bh, we allow
1378authentication settings from -oMaa to remain in force. */
1379
1380if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL;
059ec3d9
PH
1381authenticated_by = NULL;
1382
1383#ifdef SUPPORT_TLS
1384tls_cipher = tls_peerdn = NULL;
1385tls_advertised = FALSE;
1386#endif
1387
1388/* Reset ACL connection variables */
1389
38a0a95f 1390acl_var_c = NULL;
059ec3d9 1391
ca86f471 1392/* Allow for trailing 0 in the command and data buffers. */
3ee512ff 1393
ca86f471 1394smtp_cmd_buffer = (uschar *)malloc(2*smtp_cmd_buffer_size + 2);
3ee512ff 1395if (smtp_cmd_buffer == NULL)
059ec3d9
PH
1396 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
1397 "malloc() failed for SMTP command buffer");
ca86f471 1398smtp_data_buffer = smtp_cmd_buffer + smtp_cmd_buffer_size + 1;
059ec3d9
PH
1399
1400/* For batched input, the protocol setting can be overridden from the
1401command line by a trusted caller. */
1402
1403if (smtp_batched_input)
1404 {
1405 if (received_protocol == NULL) received_protocol = US"local-bsmtp";
1406 }
1407
1408/* For non-batched SMTP input, the protocol setting is forced here. It will be
1409reset later if any of EHLO/AUTH/STARTTLS are received. */
1410
1411else
1412 received_protocol =
1413 protocols[pnormal] + ((sender_host_address != NULL)? pnlocal : 0);
1414
1415/* Set up the buffer for inputting using direct read() calls, and arrange to
1416call the local functions instead of the standard C ones. */
1417
1418smtp_inbuffer = (uschar *)malloc(in_buffer_size);
1419if (smtp_inbuffer == NULL)
1420 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
1421receive_getc = smtp_getc;
1422receive_ungetc = smtp_ungetc;
1423receive_feof = smtp_feof;
1424receive_ferror = smtp_ferror;
58eb016e 1425receive_smtp_buffered = smtp_buffered;
059ec3d9
PH
1426smtp_inptr = smtp_inend = smtp_inbuffer;
1427smtp_had_eof = smtp_had_error = 0;
1428
1429/* Set up the message size limit; this may be host-specific */
1430
d45b1de8
PH
1431thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
1432if (expand_string_message != NULL)
059ec3d9
PH
1433 {
1434 if (thismessage_size_limit == -1)
1435 log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
1436 "%s", expand_string_message);
1437 else
1438 log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: "
1439 "%s", expand_string_message);
1440 smtp_closedown(US"Temporary local problem - please try later");
1441 return FALSE;
1442 }
1443
1444/* When a message is input locally via the -bs or -bS options, sender_host_
1445unknown is set unless -oMa was used to force an IP address, in which case it
1446is checked like a real remote connection. When -bs is used from inetd, this
1447flag is not set, causing the sending host to be checked. The code that deals
1448with IP source routing (if configured) is never required for -bs or -bS and
1449the flag sender_host_notsocket is used to suppress it.
1450
1451If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
1452reserve for certain hosts and/or networks. */
1453
1454if (!sender_host_unknown)
1455 {
1456 int rc;
1457 BOOL reserved_host = FALSE;
1458
1459 /* Look up IP options (source routing info) on the socket if this is not an
1460 -oMa "host", and if any are found, log them and drop the connection.
1461
1462 Linux (and others now, see below) is different to everyone else, so there
1463 has to be some conditional compilation here. Versions of Linux before 2.1.15
1464 used a structure whose name was "options". Somebody finally realized that
1465 this name was silly, and it got changed to "ip_options". I use the
1466 newer name here, but there is a fudge in the script that sets up os.h
1467 to define a macro in older Linux systems.
1468
1469 Sigh. Linux is a fast-moving target. Another generation of Linux uses
1470 glibc 2, which has chosen ip_opts for the structure name. This is now
1471 really a glibc thing rather than a Linux thing, so the condition name
1472 has been changed to reflect this. It is relevant also to GNU/Hurd.
1473
1474 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
1475 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
1476 a special macro defined in the os.h file.
1477
1478 Some DGUX versions on older hardware appear not to support IP options at
1479 all, so there is now a general macro which can be set to cut out this
1480 support altogether.
1481
1482 How to do this properly in IPv6 is not yet known. */
1483
1484 #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
1485
1486 #ifdef GLIBC_IP_OPTIONS
1487 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
1488 #define OPTSTYLE 1
1489 #else
1490 #define OPTSTYLE 2
1491 #endif
1492 #elif defined DARWIN_IP_OPTIONS
1493 #define OPTSTYLE 2
1494 #else
1495 #define OPTSTYLE 3
1496 #endif
1497
1498 if (!host_checking && !sender_host_notsocket)
1499 {
1500 #if OPTSTYLE == 1
36a3b041 1501 EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
059ec3d9
PH
1502 struct ip_options *ipopt = store_get(optlen);
1503 #elif OPTSTYLE == 2
1504 struct ip_opts ipoptblock;
1505 struct ip_opts *ipopt = &ipoptblock;
36a3b041 1506 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
1507 #else
1508 struct ipoption ipoptblock;
1509 struct ipoption *ipopt = &ipoptblock;
36a3b041 1510 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
1511 #endif
1512
1513 /* Occasional genuine failures of getsockopt() have been seen - for
1514 example, "reset by peer". Therefore, just log and give up on this
1515 call, unless the error is ENOPROTOOPT. This error is given by systems
1516 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
1517 of writing. So for that error, carry on - we just can't do an IP options
1518 check. */
1519
1520 DEBUG(D_receive) debug_printf("checking for IP options\n");
1521
1522 if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt),
1523 &optlen) < 0)
1524 {
1525 if (errno != ENOPROTOOPT)
1526 {
1527 log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
1528 host_and_ident(FALSE), strerror(errno));
1529 smtp_printf("451 SMTP service not available\r\n");
1530 return FALSE;
1531 }
1532 }
1533
1534 /* Deal with any IP options that are set. On the systems I have looked at,
1535 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
1536 more logging data than will fit in big_buffer. Nevertheless, after somebody
1537 questioned this code, I've added in some paranoid checking. */
1538
1539 else if (optlen > 0)
1540 {
1541 uschar *p = big_buffer;
1542 uschar *pend = big_buffer + big_buffer_size;
1543 uschar *opt, *adptr;
1544 int optcount;
1545 struct in_addr addr;
1546
1547 #if OPTSTYLE == 1
1548 uschar *optstart = (uschar *)(ipopt->__data);
1549 #elif OPTSTYLE == 2
1550 uschar *optstart = (uschar *)(ipopt->ip_opts);
1551 #else
1552 uschar *optstart = (uschar *)(ipopt->ipopt_list);
1553 #endif
1554
1555 DEBUG(D_receive) debug_printf("IP options exist\n");
1556
1557 Ustrcpy(p, "IP options on incoming call:");
1558 p += Ustrlen(p);
1559
1560 for (opt = optstart; opt != NULL &&
1561 opt < (uschar *)(ipopt) + optlen;)
1562 {
1563 switch (*opt)
1564 {
1565 case IPOPT_EOL:
1566 opt = NULL;
1567 break;
1568
1569 case IPOPT_NOP:
1570 opt++;
1571 break;
1572
1573 case IPOPT_SSRR:
1574 case IPOPT_LSRR:
1575 if (!string_format(p, pend-p, " %s [@%s",
1576 (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
1577 #if OPTSTYLE == 1
1578 inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
1579 #elif OPTSTYLE == 2
1580 inet_ntoa(ipopt->ip_dst)))
1581 #else
1582 inet_ntoa(ipopt->ipopt_dst)))
1583 #endif
1584 {
1585 opt = NULL;
1586 break;
1587 }
1588
1589 p += Ustrlen(p);
1590 optcount = (opt[1] - 3) / sizeof(struct in_addr);
1591 adptr = opt + 3;
1592 while (optcount-- > 0)
1593 {
1594 memcpy(&addr, adptr, sizeof(addr));
1595 if (!string_format(p, pend - p - 1, "%s%s",
1596 (optcount == 0)? ":" : "@", inet_ntoa(addr)))
1597 {
1598 opt = NULL;
1599 break;
1600 }
1601 p += Ustrlen(p);
1602 adptr += sizeof(struct in_addr);
1603 }
1604 *p++ = ']';
1605 opt += opt[1];
1606 break;
1607
1608 default:
1609 {
1610 int i;
1611 if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
1612 Ustrcat(p, "[ ");
1613 p += 2;
1614 for (i = 0; i < opt[1]; i++)
1615 {
1616 sprintf(CS p, "%2.2x ", opt[i]);
1617 p += 3;
1618 }
1619 *p++ = ']';
1620 }
1621 opt += opt[1];
1622 break;
1623 }
1624 }
1625
1626 *p = 0;
1627 log_write(0, LOG_MAIN, "%s", big_buffer);
1628
1629 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
1630
1631 log_write(0, LOG_MAIN|LOG_REJECT,
1632 "connection from %s refused (IP options)", host_and_ident(FALSE));
1633
1634 smtp_printf("554 SMTP service not available\r\n");
1635 return FALSE;
1636 }
1637
1638 /* Length of options = 0 => there are no options */
1639
1640 else DEBUG(D_receive) debug_printf("no IP options found\n");
1641 }
1642 #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
1643
1644 /* Set keep-alive in socket options. The option is on by default. This
1645 setting is an attempt to get rid of some hanging connections that stick in
1646 read() when the remote end (usually a dialup) goes away. */
1647
1648 if (smtp_accept_keepalive && !sender_host_notsocket)
1649 ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
1650
1651 /* If the current host matches host_lookup, set the name by doing a
1652 reverse lookup. On failure, sender_host_name will be NULL and
1653 host_lookup_failed will be TRUE. This may or may not be serious - optional
1654 checks later. */
1655
1656 if (verify_check_host(&host_lookup) == OK)
1657 {
1658 (void)host_name_lookup();
1659 host_build_sender_fullhost();
1660 }
1661
1662 /* Delay this until we have the full name, if it is looked up. */
1663
1664 set_process_info("handling incoming connection from %s",
1665 host_and_ident(FALSE));
1666
1667 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
1668 smtps port for use with older style SSL MTAs. */
1669
1670 #ifdef SUPPORT_TLS
83da1223
PH
1671 if (tls_on_connect &&
1672 tls_server_start(tls_require_ciphers,
1673 gnutls_require_mac, gnutls_require_kx, gnutls_require_proto) != OK)
059ec3d9
PH
1674 return FALSE;
1675 #endif
1676
1677 /* Test for explicit connection rejection */
1678
1679 if (verify_check_host(&host_reject_connection) == OK)
1680 {
1681 log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
1682 "from %s (host_reject_connection)", host_and_ident(FALSE));
1683 smtp_printf("554 SMTP service not available\r\n");
1684 return FALSE;
1685 }
1686
afb3eaaf
PH
1687 /* Test with TCP Wrappers if so configured. There is a problem in that
1688 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
1689 such as disks dying. In these cases, it is desirable to reject with a 4xx
1690 error instead of a 5xx error. There isn't a "right" way to detect such
1691 problems. The following kludge is used: errno is zeroed before calling
1692 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
1693 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
1694 not exist). */
059ec3d9
PH
1695
1696 #ifdef USE_TCP_WRAPPERS
afb3eaaf 1697 errno = 0;
5dc43717
JJ
1698 tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name);
1699 if (tcp_wrappers_name == NULL)
1700 {
1701 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
1702 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
1703 expand_string_message);
1704 }
1705 if (!hosts_ctl(tcp_wrappers_name,
059ec3d9
PH
1706 (sender_host_name == NULL)? STRING_UNKNOWN : CS sender_host_name,
1707 (sender_host_address == NULL)? STRING_UNKNOWN : CS sender_host_address,
1708 (sender_ident == NULL)? STRING_UNKNOWN : CS sender_ident))
1709 {
afb3eaaf
PH
1710 if (errno == 0 || errno == ENOENT)
1711 {
1712 HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
1713 log_write(L_connection_reject,
1714 LOG_MAIN|LOG_REJECT, "refused connection from %s "
1715 "(tcp wrappers)", host_and_ident(FALSE));
1716 smtp_printf("554 SMTP service not available\r\n");
1717 }
1718 else
1719 {
1720 int save_errno = errno;
1721 HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
1722 "errno value %d\n", save_errno);
1723 log_write(L_connection_reject,
1724 LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
1725 "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
1726 smtp_printf("451 Temporary local problem - please try later\r\n");
1727 }
059ec3d9
PH
1728 return FALSE;
1729 }
1730 #endif
1731
b01dd148
PH
1732 /* Check for reserved slots. The value of smtp_accept_count has already been
1733 incremented to include this process. */
059ec3d9
PH
1734
1735 if (smtp_accept_max > 0 &&
b01dd148 1736 smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
059ec3d9
PH
1737 {
1738 if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
1739 {
1740 log_write(L_connection_reject,
1741 LOG_MAIN, "temporarily refused connection from %s: not in "
1742 "reserve list: connected=%d max=%d reserve=%d%s",
b01dd148 1743 host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
059ec3d9
PH
1744 smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
1745 smtp_printf("421 %s: Too many concurrent SMTP connections; "
1746 "please try again later\r\n", smtp_active_hostname);
1747 return FALSE;
1748 }
1749 reserved_host = TRUE;
1750 }
1751
1752 /* If a load level above which only messages from reserved hosts are
1753 accepted is set, check the load. For incoming calls via the daemon, the
1754 check is done in the superior process if there are no reserved hosts, to
1755 save a fork. In all cases, the load average will already be available
1756 in a global variable at this point. */
1757
1758 if (smtp_load_reserve >= 0 &&
1759 load_average > smtp_load_reserve &&
1760 !reserved_host &&
1761 verify_check_host(&smtp_reserve_hosts) != OK)
1762 {
1763 log_write(L_connection_reject,
1764 LOG_MAIN, "temporarily refused connection from %s: not in "
1765 "reserve list and load average = %.2f", host_and_ident(FALSE),
1766 (double)load_average/1000.0);
1767 smtp_printf("421 %s: Too much load; please try again later\r\n",
1768 smtp_active_hostname);
1769 return FALSE;
1770 }
1771
1772 /* Determine whether unqualified senders or recipients are permitted
1773 for this host. Unfortunately, we have to do this every time, in order to
1774 set the flags so that they can be inspected when considering qualifying
1775 addresses in the headers. For a site that permits no qualification, this
1776 won't take long, however. */
1777
1778 allow_unqualified_sender =
1779 verify_check_host(&sender_unqualified_hosts) == OK;
1780
1781 allow_unqualified_recipient =
1782 verify_check_host(&recipient_unqualified_hosts) == OK;
1783
1784 /* Determine whether HELO/EHLO is required for this host. The requirement
1785 can be hard or soft. */
1786
1787 helo_required = verify_check_host(&helo_verify_hosts) == OK;
1788 if (!helo_required)
1789 helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
1790
1791 /* Determine whether this hosts is permitted to send syntactic junk
1792 after a HELO or EHLO command. */
1793
1794 helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
1795 }
1796
1797/* For batch SMTP input we are now done. */
1798
1799if (smtp_batched_input) return TRUE;
1800
1801/* Run the ACL if it exists */
1802
4e88a19f 1803user_msg = NULL;
059ec3d9
PH
1804if (acl_smtp_connect != NULL)
1805 {
1806 int rc;
64ffc24f 1807 rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
059ec3d9
PH
1808 &log_msg);
1809 if (rc != OK)
1810 {
1811 (void)smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
1812 return FALSE;
1813 }
1814 }
1815
1816/* Output the initial message for a two-way SMTP connection. It may contain
1817newlines, which then cause a multi-line response to be given. */
1818
4e88a19f
PH
1819code = US"220"; /* Default status code */
1820esc = US""; /* Default extended status code */
1821esclen = 0; /* Length of esc */
1822
1823if (user_msg == NULL)
1824 {
1825 s = expand_string(smtp_banner);
1826 if (s == NULL)
1827 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
1828 "failed: %s", smtp_banner, expand_string_message);
1829 }
1830else
1831 {
1832 int codelen = 3;
1833 s = user_msg;
1834 smtp_message_code(&code, &codelen, &s, NULL);
d6a96edc 1835 if (codelen > 4)
4e88a19f
PH
1836 {
1837 esc = code + 4;
1838 esclen = codelen - 4;
1839 }
1840 }
059ec3d9
PH
1841
1842/* Remove any terminating newlines; might as well remove trailing space too */
1843
1844p = s + Ustrlen(s);
1845while (p > s && isspace(p[-1])) p--;
1846*p = 0;
1847
1848/* It seems that CC:Mail is braindead, and assumes that the greeting message
1849is all contained in a single IP packet. The original code wrote out the
1850greeting using several calls to fprint/fputc, and on busy servers this could
1851cause it to be split over more than one packet - which caused CC:Mail to fall
1852over when it got the second part of the greeting after sending its first
1853command. Sigh. To try to avoid this, build the complete greeting message
1854first, and output it in one fell swoop. This gives a better chance of it
1855ending up as a single packet. */
1856
1857ss = store_get(size);
1858ptr = 0;
1859
1860p = s;
1861do /* At least once, in case we have an empty string */
1862 {
1863 int len;
1864 uschar *linebreak = Ustrchr(p, '\n');
4e88a19f 1865 ss = string_cat(ss, &size, &ptr, code, 3);
059ec3d9
PH
1866 if (linebreak == NULL)
1867 {
1868 len = Ustrlen(p);
4e88a19f 1869 ss = string_cat(ss, &size, &ptr, US" ", 1);
059ec3d9
PH
1870 }
1871 else
1872 {
1873 len = linebreak - p;
4e88a19f 1874 ss = string_cat(ss, &size, &ptr, US"-", 1);
059ec3d9 1875 }
4e88a19f 1876 ss = string_cat(ss, &size, &ptr, esc, esclen);
059ec3d9
PH
1877 ss = string_cat(ss, &size, &ptr, p, len);
1878 ss = string_cat(ss, &size, &ptr, US"\r\n", 2);
1879 p += len;
1880 if (linebreak != NULL) p++;
1881 }
1882while (*p != 0);
1883
1884ss[ptr] = 0; /* string_cat leaves room for this */
1885
1886/* Before we write the banner, check that there is no input pending, unless
1887this synchronisation check is disabled. */
1888
a14e5636 1889if (!check_sync())
059ec3d9 1890 {
a14e5636
PH
1891 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
1892 "synchronization error (input sent without waiting for greeting): "
1893 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
1894 string_printing(smtp_inptr));
1895 smtp_printf("554 SMTP synchronization error\r\n");
1896 return FALSE;
059ec3d9
PH
1897 }
1898
1899/* Now output the banner */
1900
1901smtp_printf("%s", ss);
1902return TRUE;
1903}
1904
1905
1906
1907
1908
1909/*************************************************
1910* Handle SMTP syntax and protocol errors *
1911*************************************************/
1912
1913/* Write to the log for SMTP syntax errors in incoming commands, if configured
1914to do so. Then transmit the error response. The return value depends on the
1915number of syntax and protocol errors in this SMTP session.
1916
1917Arguments:
1918 type error type, given as a log flag bit
1919 code response code; <= 0 means don't send a response
1920 data data to reflect in the response (can be NULL)
1921 errmess the error message
1922
1923Returns: -1 limit of syntax/protocol errors NOT exceeded
1924 +1 limit of syntax/protocol errors IS exceeded
1925
1926These values fit in with the values of the "done" variable in the main
1927processing loop in smtp_setup_msg(). */
1928
1929static int
1930synprot_error(int type, int code, uschar *data, uschar *errmess)
1931{
1932int yield = -1;
1933
1934log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
1935 (type == L_smtp_syntax_error)? "syntax" : "protocol",
3ee512ff 1936 string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
059ec3d9
PH
1937
1938if (++synprot_error_count > smtp_max_synprot_errors)
1939 {
1940 yield = 1;
1941 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
1942 "syntax or protocol errors (last command was \"%s\")",
3ee512ff 1943 host_and_ident(FALSE), smtp_cmd_buffer);
059ec3d9
PH
1944 }
1945
1946if (code > 0)
1947 {
1948 smtp_printf("%d%c%s%s%s\r\n", code, (yield == 1)? '-' : ' ',
1949 (data == NULL)? US"" : data, (data == NULL)? US"" : US": ", errmess);
1950 if (yield == 1)
1951 smtp_printf("%d Too many syntax or protocol errors\r\n", code);
1952 }
1953
1954return yield;
1955}
1956
1957
1958
1959
1960/*************************************************
1961* Log incomplete transactions *
1962*************************************************/
1963
1964/* This function is called after a transaction has been aborted by RSET, QUIT,
1965connection drops or other errors. It logs the envelope information received
1966so far in order to preserve address verification attempts.
1967
1968Argument: string to indicate what aborted the transaction
1969Returns: nothing
1970*/
1971
1972static void
1973incomplete_transaction_log(uschar *what)
1974{
1975if (sender_address == NULL || /* No transaction in progress */
1976 (log_write_selector & L_smtp_incomplete_transaction) == 0 /* Not logging */
1977 ) return;
1978
1979/* Build list of recipients for logging */
1980
1981if (recipients_count > 0)
1982 {
1983 int i;
1984 raw_recipients = store_get(recipients_count * sizeof(uschar *));
1985 for (i = 0; i < recipients_count; i++)
1986 raw_recipients[i] = recipients_list[i].address;
1987 raw_recipients_count = recipients_count;
1988 }
1989
1990log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
1991 "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
1992}
1993
1994
1995
1996
1997/*************************************************
1998* Send SMTP response, possibly multiline *
1999*************************************************/
2000
2001/* There are, it seems, broken clients out there that cannot handle multiline
2002responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
2003output nothing for non-final calls, and only the first line for anything else.
2004
2005Arguments:
a5bd321b 2006 code SMTP code, may involve extended status codes
d6a96edc 2007 codelen length of smtp code; if > 4 there's an ESC
059ec3d9
PH
2008 final FALSE if the last line isn't the final line
2009 msg message text, possibly containing newlines
2010
2011Returns: nothing
2012*/
2013
2014void
a5bd321b 2015smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
059ec3d9 2016{
a5bd321b
PH
2017int esclen = 0;
2018uschar *esc = US"";
2019
059ec3d9
PH
2020if (!final && no_multiline_responses) return;
2021
d6a96edc 2022if (codelen > 4)
a5bd321b
PH
2023 {
2024 esc = code + 4;
2025 esclen = codelen - 4;
2026 }
2027
2679d413
PH
2028/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
2029have had the same. Note: this code is also present in smtp_printf(). It would
2030be tidier to have it only in one place, but when it was added, it was easier to
2031do it that way, so as not to have to mess with the code for the RCPT command,
2032which sometimes uses smtp_printf() and sometimes smtp_respond(). */
2033
2034if (rcpt_in_progress)
2035 {
2036 if (rcpt_smtp_response == NULL)
2037 rcpt_smtp_response = string_copy(msg);
2038 else if (rcpt_smtp_response_same &&
2039 Ustrcmp(rcpt_smtp_response, msg) != 0)
2040 rcpt_smtp_response_same = FALSE;
2041 rcpt_in_progress = FALSE;
2042 }
2043
2044/* Not output the message, splitting it up into multiple lines if necessary. */
2045
059ec3d9
PH
2046for (;;)
2047 {
2048 uschar *nl = Ustrchr(msg, '\n');
2049 if (nl == NULL)
2050 {
a5bd321b 2051 smtp_printf("%.3s%c%.*s%s\r\n", code, final? ' ':'-', esclen, esc, msg);
059ec3d9
PH
2052 return;
2053 }
2054 else if (nl[1] == 0 || no_multiline_responses)
2055 {
a5bd321b
PH
2056 smtp_printf("%.3s%c%.*s%.*s\r\n", code, final? ' ':'-', esclen, esc,
2057 (int)(nl - msg), msg);
059ec3d9
PH
2058 return;
2059 }
2060 else
2061 {
a5bd321b 2062 smtp_printf("%.3s-%.*s%.*s\r\n", code, esclen, esc, (int)(nl - msg), msg);
059ec3d9
PH
2063 msg = nl + 1;
2064 while (isspace(*msg)) msg++;
2065 }
2066 }
2067}
2068
2069
2070
2071
2072/*************************************************
4e88a19f
PH
2073* Parse user SMTP message *
2074*************************************************/
2075
2076/* This function allows for user messages overriding the response code details
2077by providing a suitable response code string at the start of the message
2078user_msg. Check the message for starting with a response code and optionally an
2079extended status code. If found, check that the first digit is valid, and if so,
2080change the code pointer and length to use the replacement. An invalid code
2081causes a panic log; in this case, if the log messages is the same as the user
2082message, we must also adjust the value of the log message to show the code that
2083is actually going to be used (the original one).
2084
2085This function is global because it is called from receive.c as well as within
2086this module.
2087
d6a96edc
PH
2088Note that the code length returned includes the terminating whitespace
2089character, which is always included in the regex match.
2090
4e88a19f
PH
2091Arguments:
2092 code SMTP code, may involve extended status codes
d6a96edc 2093 codelen length of smtp code; if > 4 there's an ESC
4e88a19f
PH
2094 msg message text
2095 log_msg optional log message, to be adjusted with the new SMTP code
2096
2097Returns: nothing
2098*/
2099
2100void
2101smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg)
2102{
2103int n;
2104int ovector[3];
2105
2106if (msg == NULL || *msg == NULL) return;
2107
2108n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
2109 PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int));
2110if (n < 0) return;
2111
2112if ((*msg)[0] != (*code)[0])
2113 {
2114 log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
2115 "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
2116 if (log_msg != NULL && *log_msg == *msg)
2117 *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
2118 }
2119else
2120 {
2121 *code = *msg;
2122 *codelen = ovector[1]; /* Includes final space */
2123 }
2124*msg += ovector[1]; /* Chop the code off the message */
2125return;
2126}
2127
2128
2129
2130
2131/*************************************************
059ec3d9
PH
2132* Handle an ACL failure *
2133*************************************************/
2134
2135/* This function is called when acl_check() fails. As well as calls from within
2136this module, it is called from receive.c for an ACL after DATA. It sorts out
2137logging the incident, and sets up the error response. A message containing
2138newlines is turned into a multiline SMTP response, but for logging, only the
2139first line is used.
2140
a5bd321b
PH
2141There's a table of default permanent failure response codes to use in
2142globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
2143defaults disabled in Exim. However, discussion in connection with RFC 821bis
2144(aka RFC 2821) has concluded that the response should be 252 in the disabled
2145state, because there are broken clients that try VRFY before RCPT. A 5xx
2146response should be given only when the address is positively known to be
2147undeliverable. Sigh. Also, for ETRN, 458 is given on refusal, and for AUTH,
2148503.
2149
2150From Exim 4.63, it is possible to override the response code details by
2151providing a suitable response code string at the start of the message provided
2152in user_msg. The code's first digit is checked for validity.
059ec3d9
PH
2153
2154Arguments:
2155 where where the ACL was called from
2156 rc the failure code
2157 user_msg a message that can be included in an SMTP response
2158 log_msg a message for logging
2159
2160Returns: 0 in most cases
2161 2 if the failure code was FAIL_DROP, in which case the
2162 SMTP connection should be dropped (this value fits with the
2163 "done" variable in smtp_setup_msg() below)
2164*/
2165
2166int
2167smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
2168{
059ec3d9 2169BOOL drop = rc == FAIL_DROP;
a5bd321b 2170int codelen = 3;
a5bd321b 2171uschar *smtp_code;
059ec3d9
PH
2172uschar *lognl;
2173uschar *sender_info = US"";
64ffc24f 2174uschar *what =
8523533c 2175#ifdef WITH_CONTENT_SCAN
64ffc24f 2176 (where == ACL_WHERE_MIME)? US"during MIME ACL checks" :
8e669ac1 2177#endif
64ffc24f
PH
2178 (where == ACL_WHERE_PREDATA)? US"DATA" :
2179 (where == ACL_WHERE_DATA)? US"after DATA" :
ca86f471 2180 (smtp_cmd_data == NULL)?
64ffc24f 2181 string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) :
ca86f471 2182 string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data);
059ec3d9
PH
2183
2184if (drop) rc = FAIL;
2185
4e88a19f 2186/* Set the default SMTP code, and allow a user message to change it. */
a5bd321b
PH
2187
2188smtp_code = (rc != FAIL)? US"451" : acl_wherecodes[where];
4e88a19f 2189smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg);
a5bd321b 2190
059ec3d9
PH
2191/* We used to have sender_address here; however, there was a bug that was not
2192updating sender_address after a rewrite during a verify. When this bug was
2193fixed, sender_address at this point became the rewritten address. I'm not sure
2194this is what should be logged, so I've changed to logging the unrewritten
2195address to retain backward compatibility. */
2196
8523533c 2197#ifndef WITH_CONTENT_SCAN
059ec3d9 2198if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
8523533c
TK
2199#else
2200if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
2201#endif
059ec3d9
PH
2202 {
2203 sender_info = string_sprintf("F=<%s> ", (sender_address_unrewritten != NULL)?
2204 sender_address_unrewritten : sender_address);
2205 }
2206
2207/* If there's been a sender verification failure with a specific message, and
2208we have not sent a response about it yet, do so now, as a preliminary line for
278c6e6c
PH
2209failures, but not defers. However, always log it for defer, and log it for fail
2210unless the sender_verify_fail log selector has been turned off. */
059ec3d9
PH
2211
2212if (sender_verified_failed != NULL &&
2213 !testflag(sender_verified_failed, af_sverify_told))
2214 {
2679d413
PH
2215 BOOL save_rcpt_in_progress = rcpt_in_progress;
2216 rcpt_in_progress = FALSE; /* So as not to treat these as the error */
2217
059ec3d9
PH
2218 setflag(sender_verified_failed, af_sverify_told);
2219
278c6e6c
PH
2220 if (rc != FAIL || (log_extra_selector & LX_sender_verify_fail) != 0)
2221 log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
2222 host_and_ident(TRUE),
2223 ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
2224 sender_verified_failed->address,
2225 (sender_verified_failed->message == NULL)? US"" :
2226 string_sprintf(": %s", sender_verified_failed->message));
059ec3d9
PH
2227
2228 if (rc == FAIL && sender_verified_failed->user_message != NULL)
a5bd321b 2229 smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
059ec3d9
PH
2230 testflag(sender_verified_failed, af_verify_pmfail)?
2231 "Postmaster verification failed while checking <%s>\n%s\n"
2232 "Several RFCs state that you are required to have a postmaster\n"
2233 "mailbox for each mail domain. This host does not accept mail\n"
2234 "from domains whose servers reject the postmaster address."
2235 :
2236 testflag(sender_verified_failed, af_verify_nsfail)?
2237 "Callback setup failed while verifying <%s>\n%s\n"
2238 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
2239 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
2240 "RFC requirements, and stops you from receiving standard bounce\n"
2241 "messages. This host does not accept mail from domains whose servers\n"
2242 "refuse bounces."
2243 :
2244 "Verification failed for <%s>\n%s",
2245 sender_verified_failed->address,
2246 sender_verified_failed->user_message));
2679d413
PH
2247
2248 rcpt_in_progress = save_rcpt_in_progress;
059ec3d9
PH
2249 }
2250
2251/* Sort out text for logging */
2252
2253log_msg = (log_msg == NULL)? US"" : string_sprintf(": %s", log_msg);
2254lognl = Ustrchr(log_msg, '\n');
2255if (lognl != NULL) *lognl = 0;
2256
2257/* Send permanent failure response to the command, but the code used isn't
2258always a 5xx one - see comments at the start of this function. If the original
2259rc was FAIL_DROP we drop the connection and yield 2. */
2260
a5bd321b 2261if (rc == FAIL) smtp_respond(smtp_code, codelen, TRUE, (user_msg == NULL)?
059ec3d9
PH
2262 US"Administrative prohibition" : user_msg);
2263
2264/* Send temporary failure response to the command. Don't give any details,
2265unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
2266verb, and for a header verify when smtp_return_error_details is set.
2267
2268This conditional logic is all somewhat of a mess because of the odd
2269interactions between temp_details and return_error_details. One day it should
2270be re-implemented in a tidier fashion. */
2271
2272else
2273 {
2274 if (acl_temp_details && user_msg != NULL)
2275 {
2276 if (smtp_return_error_details &&
2277 sender_verified_failed != NULL &&
2278 sender_verified_failed->message != NULL)
2279 {
a5bd321b 2280 smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
059ec3d9 2281 }
a5bd321b 2282 smtp_respond(smtp_code, codelen, TRUE, user_msg);
059ec3d9
PH
2283 }
2284 else
a5bd321b
PH
2285 smtp_respond(smtp_code, codelen, TRUE,
2286 US"Temporary local problem - please try later");
059ec3d9
PH
2287 }
2288
6ea85e9a
PH
2289/* Log the incident to the logs that are specified by log_reject_target
2290(default main, reject). This can be empty to suppress logging of rejections. If
2291the connection is not forcibly to be dropped, return 0. Otherwise, log why it
2292is closing if required and return 2. */
059ec3d9 2293
6ea85e9a
PH
2294if (log_reject_target != 0)
2295 log_write(0, log_reject_target, "%s %s%srejected %s%s",
2296 host_and_ident(TRUE),
2297 sender_info, (rc == FAIL)? US"" : US"temporarily ", what, log_msg);
059ec3d9
PH
2298
2299if (!drop) return 0;
2300
2301log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
2302 smtp_get_connection_info());
8f128379
PH
2303
2304/* Run the not-quit ACL, but without any custom messages. This should not be a
2305problem, because we get here only if some other ACL has issued "drop", and
2306in that case, *its* custom messages will have been used above. */
2307
2308smtp_notquit_exit(US"acl-drop", NULL, NULL);
059ec3d9
PH
2309return 2;
2310}
2311
2312
2313
2314
2315/*************************************************
8f128379
PH
2316* Handle SMTP exit when QUIT is not given *
2317*************************************************/
2318
2319/* This function provides a logging/statistics hook for when an SMTP connection
2320is dropped on the floor or the other end goes away. It's a global function
2321because it's called from receive.c as well as this module. As well as running
2322the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
2323response, either with a custom message from the ACL, or using a default. There
2324is one case, however, when no message is output - after "drop". In that case,
2325the ACL that obeyed "drop" has already supplied the custom message, and NULL is
2326passed to this function.
2327
2328In case things go wrong while processing this function, causing an error that
2329may re-enter this funtion, there is a recursion check.
2330
2331Arguments:
2332 reason What $smtp_notquit_reason will be set to in the ACL;
2333 if NULL, the ACL is not run
2334 code The error code to return as part of the response
2335 defaultrespond The default message if there's no user_msg
2336
2337Returns: Nothing
2338*/
2339
2340void
2341smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
2342{
2343int rc;
2344uschar *user_msg = NULL;
2345uschar *log_msg = NULL;
2346
2347/* Check for recursive acll */
2348
2349if (smtp_exit_function_called)
2350 {
2351 log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
2352 reason);
2353 return;
2354 }
2355smtp_exit_function_called = TRUE;
2356
2357/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
2358
2359if (acl_smtp_notquit != NULL && reason != NULL)
2360 {
2361 smtp_notquit_reason = reason;
2362 rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
2363 &log_msg);
2364 if (rc == ERROR)
2365 log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
2366 log_msg);
2367 }
2368
2369/* Write an SMTP response if we are expected to give one. As the default
2370responses are all internal, they should always fit in the buffer, but code a
2371warning, just in case. Note that string_vformat() still leaves a complete
2372string, even if it is incomplete. */
2373
2374if (code != NULL && defaultrespond != NULL)
2375 {
2376 if (user_msg == NULL)
2377 {
2378 uschar buffer[128];
2379 va_list ap;
2380 va_start(ap, defaultrespond);
2381 if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap))
2382 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()");
2383 smtp_printf("%s %s\r\n", code, buffer);
2384 va_end(ap);
2385 }
2386 else
2387 smtp_respond(code, 3, TRUE, user_msg);
2388 mac_smtp_fflush();
2389 }
2390}
2391
2392
2393
2394
2395/*************************************************
d7b47fd0
PH
2396* Verify HELO argument *
2397*************************************************/
2398
2399/* This function is called if helo_verify_hosts or helo_try_verify_hosts is
2400matched. It is also called from ACL processing if verify = helo is used and
2401verification was not previously tried (i.e. helo_try_verify_hosts was not
2402matched). The result of its processing is to set helo_verified and
2403helo_verify_failed. These variables should both be FALSE for this function to
2404be called.
2405
2406Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow
2407for IPv6 ::ffff: literals.
2408
2409Argument: none
2410Returns: TRUE if testing was completed;
2411 FALSE on a temporary failure
2412*/
2413
2414BOOL
2415smtp_verify_helo(void)
2416{
2417BOOL yield = TRUE;
2418
2419HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n",
2420 sender_helo_name);
2421
2422if (sender_helo_name == NULL)
2423 {
2424 HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n");
2425 }
2426
d1d5595c
PH
2427/* Deal with the case of -bs without an IP address */
2428
2429else if (sender_host_address == NULL)
2430 {
2431 HDEBUG(D_receive) debug_printf("no client IP address: assume success\n");
2432 helo_verified = TRUE;
2433 }
2434
2435/* Deal with the more common case when there is a sending IP address */
2436
d7b47fd0
PH
2437else if (sender_helo_name[0] == '[')
2438 {
2439 helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,
2440 Ustrlen(sender_host_address)) == 0;
2441
2442 #if HAVE_IPV6
2443 if (!helo_verified)
2444 {
2445 if (strncmpic(sender_host_address, US"::ffff:", 7) == 0)
2446 helo_verified = Ustrncmp(sender_helo_name + 1,
2447 sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0;
2448 }
2449 #endif
2450
2451 HDEBUG(D_receive)
2452 { if (helo_verified) debug_printf("matched host address\n"); }
2453 }
2454
2455/* Do a reverse lookup if one hasn't already given a positive or negative
2456response. If that fails, or the name doesn't match, try checking with a forward
2457lookup. */
2458
2459else
2460 {
2461 if (sender_host_name == NULL && !host_lookup_failed)
2462 yield = host_name_lookup() != DEFER;
2463
2464 /* If a host name is known, check it and all its aliases. */
2465
2466 if (sender_host_name != NULL)
2467 {
2468 helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0;
2469
2470 if (helo_verified)
2471 {
2472 HDEBUG(D_receive) debug_printf("matched host name\n");
2473 }
2474 else
2475 {
2476 uschar **aliases = sender_host_aliases;
2477 while (*aliases != NULL)
2478 {
2479 helo_verified = strcmpic(*aliases++, sender_helo_name) == 0;
2480 if (helo_verified) break;
2481 }
2482 HDEBUG(D_receive)
2483 {
2484 if (helo_verified)
2485 debug_printf("matched alias %s\n", *(--aliases));
2486 }
2487 }
2488 }
2489
2490 /* Final attempt: try a forward lookup of the helo name */
2491
2492 if (!helo_verified)
2493 {
2494 int rc;
2495 host_item h;
2496 h.name = sender_helo_name;
2497 h.address = NULL;
2498 h.mx = MX_NONE;
2499 h.next = NULL;
2500 HDEBUG(D_receive) debug_printf("getting IP address for %s\n",
2501 sender_helo_name);
322050c2 2502 rc = host_find_byname(&h, NULL, 0, NULL, TRUE);
d7b47fd0
PH
2503 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
2504 {
2505 host_item *hh = &h;
2506 while (hh != NULL)
2507 {
2508 if (Ustrcmp(hh->address, sender_host_address) == 0)
2509 {
2510 helo_verified = TRUE;
2511 HDEBUG(D_receive)
2512 debug_printf("IP address for %s matches calling address\n",
2513 sender_helo_name);
2514 break;
2515 }
2516 hh = hh->next;
2517 }
2518 }
2519 }
2520 }
2521
d1d5595c 2522if (!helo_verified) helo_verify_failed = TRUE; /* We've tried ... */
d7b47fd0
PH
2523return yield;
2524}
2525
2526
2527
2528
2529/*************************************************
4e88a19f
PH
2530* Send user response message *
2531*************************************************/
2532
2533/* This function is passed a default response code and a user message. It calls
2534smtp_message_code() to check and possibly modify the response code, and then
2535calls smtp_respond() to transmit the response. I put this into a function
2536just to avoid a lot of repetition.
2537
2538Arguments:
2539 code the response code
2540 user_msg the user message
2541
2542Returns: nothing
2543*/
2544
2545static void
2546smtp_user_msg(uschar *code, uschar *user_msg)
2547{
2548int len = 3;
2549smtp_message_code(&code, &len, &user_msg, NULL);
2550smtp_respond(code, len, TRUE, user_msg);
2551}
2552
2553
2554
2555
2556/*************************************************
059ec3d9
PH
2557* Initialize for SMTP incoming message *
2558*************************************************/
2559
2560/* This function conducts the initial dialogue at the start of an incoming SMTP
2561message, and builds a list of recipients. However, if the incoming message
2562is part of a batch (-bS option) a separate function is called since it would
2563be messy having tests splattered about all over this function. This function
2564therefore handles the case where interaction is occurring. The input and output
2565files are set up in smtp_in and smtp_out.
2566
2567The global recipients_list is set to point to a vector of recipient_item
2568blocks, whose number is given by recipients_count. This is extended by the
2569receive_add_recipient() function. The global variable sender_address is set to
2570the sender's address. The yield is +1 if a message has been successfully
2571started, 0 if a QUIT command was encountered or the connection was refused from
2572the particular host, or -1 if the connection was lost.
2573
2574Argument: none
2575
2576Returns: > 0 message successfully started (reached DATA)
2577 = 0 QUIT read or end of file reached or call refused
2578 < 0 lost connection
2579*/
2580
2581int
2582smtp_setup_msg(void)
2583{
2584int done = 0;
2585BOOL toomany = FALSE;
2586BOOL discarded = FALSE;
2587BOOL last_was_rej_mail = FALSE;
2588BOOL last_was_rcpt = FALSE;
2589void *reset_point = store_get(0);
2590
2591DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n");
2592
2593/* Reset for start of new message. We allow one RSET not to be counted as a
2594nonmail command, for those MTAs that insist on sending it between every
2595message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of
2596TLS between messages (an Exim client may do this if it has messages queued up
2597for the host). Note: we do NOT reset AUTH at this point. */
2598
2599smtp_reset(reset_point);
2600message_ended = END_NOTSTARTED;
2601
2602cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE;
2603cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE;
2604cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
2605#ifdef SUPPORT_TLS
2606cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE;
2607#endif
2608
2609/* Set the local signal handler for SIGTERM - it tries to end off tidily */
2610
2611os_non_restarting_signal(SIGTERM, command_sigterm_handler);
2612
2613/* Batched SMTP is handled in a different function. */
2614
2615if (smtp_batched_input) return smtp_setup_batch_msg();
2616
2617/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
2618value. The values are 2 larger than the required yield of the function. */
2619
2620while (done <= 0)
2621 {
2622 uschar **argv;
2623 uschar *etrn_command;
2624 uschar *etrn_serialize_key;
2625 uschar *errmess;
4e88a19f
PH
2626 uschar *log_msg, *smtp_code;
2627 uschar *user_msg = NULL;
059ec3d9
PH
2628 uschar *recipient = NULL;
2629 uschar *hello = NULL;
2630 uschar *set_id = NULL;
2631 uschar *s, *ss;
2632 BOOL was_rej_mail = FALSE;
2633 BOOL was_rcpt = FALSE;
2634 void (*oldsignal)(int);
2635 pid_t pid;
2636 int start, end, sender_domain, recipient_domain;
2637 int ptr, size, rc;
f78eb7c6 2638 int c, i;
059ec3d9
PH
2639 auth_instance *au;
2640
2641 switch(smtp_read_command(TRUE))
2642 {
2643 /* The AUTH command is not permitted to occur inside a transaction, and may
c46782ef
PH
2644 occur successfully only once per connection. Actually, that isn't quite
2645 true. When TLS is started, all previous information about a connection must
2646 be discarded, so a new AUTH is permitted at that time.
2647
2648 AUTH may only be used when it has been advertised. However, it seems that
2649 there are clients that send AUTH when it hasn't been advertised, some of
2650 them even doing this after HELO. And there are MTAs that accept this. Sigh.
2651 So there's a get-out that allows this to happen.
059ec3d9
PH
2652
2653 AUTH is initially labelled as a "nonmail command" so that one occurrence
2654 doesn't get counted. We change the label here so that multiple failing
2655 AUTHS will eventually hit the nonmail threshold. */
2656
2657 case AUTH_CMD:
b4ed4da0 2658 HAD(SCH_AUTH);
059ec3d9
PH
2659 authentication_failed = TRUE;
2660 cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
2661
c46782ef 2662 if (!auth_advertised && !allow_auth_unadvertised)
059ec3d9
PH
2663 {
2664 done = synprot_error(L_smtp_protocol_error, 503, NULL,
2665 US"AUTH command used when not advertised");
2666 break;
2667 }
2668 if (sender_host_authenticated != NULL)
2669 {
2670 done = synprot_error(L_smtp_protocol_error, 503, NULL,
2671 US"already authenticated");
2672 break;
2673 }
2674 if (sender_address != NULL)
2675 {
2676 done = synprot_error(L_smtp_protocol_error, 503, NULL,
2677 US"not permitted in mail transaction");
2678 break;
2679 }
2680
2681 /* Check the ACL */
2682
2683 if (acl_smtp_auth != NULL)
2684 {
64ffc24f 2685 rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, &user_msg, &log_msg);
059ec3d9
PH
2686 if (rc != OK)
2687 {
2688 done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
2689 break;
2690 }
2691 }
2692
2693 /* Find the name of the requested authentication mechanism. */
2694
ca86f471
PH
2695 s = smtp_cmd_data;
2696 while ((c = *smtp_cmd_data) != 0 && !isspace(c))
059ec3d9
PH
2697 {
2698 if (!isalnum(c) && c != '-' && c != '_')
2699 {
2700 done = synprot_error(L_smtp_syntax_error, 501, NULL,
2701 US"invalid character in authentication mechanism name");
2702 goto COMMAND_LOOP;
2703 }
ca86f471 2704 smtp_cmd_data++;
059ec3d9
PH
2705 }
2706
2707 /* If not at the end of the line, we must be at white space. Terminate the
2708 name and move the pointer on to any data that may be present. */
2709
ca86f471 2710 if (*smtp_cmd_data != 0)
059ec3d9 2711 {
ca86f471
PH
2712 *smtp_cmd_data++ = 0;
2713 while (isspace(*smtp_cmd_data)) smtp_cmd_data++;
059ec3d9
PH
2714 }
2715
2716 /* Search for an authentication mechanism which is configured for use
c46782ef
PH
2717 as a server and which has been advertised (unless, sigh, allow_auth_
2718 unadvertised is set). */
059ec3d9
PH
2719
2720 for (au = auths; au != NULL; au = au->next)
2721 {
2722 if (strcmpic(s, au->public_name) == 0 && au->server &&
c46782ef 2723 (au->advertised || allow_auth_unadvertised)) break;
059ec3d9
PH
2724 }
2725
2726 if (au == NULL)
2727 {
2728 done = synprot_error(L_smtp_protocol_error, 504, NULL,
2729 string_sprintf("%s authentication mechanism not supported", s));
2730 break;
2731 }
2732
f78eb7c6
PH
2733 /* Run the checking code, passing the remainder of the command line as
2734 data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
2735 it as the only set numerical variable. The authenticator may set $auth<n>
2736 and also set other numeric variables. The $auth<n> variables are preferred
2737 nowadays; the numerical variables remain for backwards compatibility.
059ec3d9 2738
f78eb7c6
PH
2739 Afterwards, have a go at expanding the set_id string, even if
2740 authentication failed - for bad passwords it can be useful to log the
2741 userid. On success, require set_id to expand and exist, and put it in
2742 authenticated_id. Save this in permanent store, as the working store gets
2743 reset at HELO, RSET, etc. */
2744
2745 for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
059ec3d9
PH
2746 expand_nmax = 0;
2747 expand_nlength[0] = 0; /* $0 contains nothing */
2748
ca86f471 2749 c = (au->info->servercode)(au, smtp_cmd_data);
059ec3d9
PH
2750 if (au->set_id != NULL) set_id = expand_string(au->set_id);
2751 expand_nmax = -1; /* Reset numeric variables */
f78eb7c6 2752 for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
059ec3d9 2753
0612b098
PH
2754 /* The value of authenticated_id is stored in the spool file and printed in
2755 log lines. It must not contain binary zeros or newline characters. In
2756 normal use, it never will, but when playing around or testing, this error
2757 can (did) happen. To guard against this, ensure that the id contains only
2758 printing characters. */
2759
2760 if (set_id != NULL) set_id = string_printing(set_id);
2761
059ec3d9
PH
2762 /* For the non-OK cases, set up additional logging data if set_id
2763 is not empty. */
2764
2765 if (c != OK)
2766 {
2767 if (set_id != NULL && *set_id != 0)
2768 set_id = string_sprintf(" (set_id=%s)", set_id);
2769 else set_id = US"";
2770 }
2771
2772 /* Switch on the result */
2773
2774 switch(c)
2775 {
2776 case OK:
2777 if (au->set_id == NULL || set_id != NULL) /* Complete success */
2778 {
2779 if (set_id != NULL) authenticated_id = string_copy_malloc(set_id);
2780 sender_host_authenticated = au->name;
2781 authentication_failed = FALSE;
2782 received_protocol =
2783 protocols[pextend + pauthed + ((tls_active >= 0)? pcrpted:0)] +
2784 ((sender_host_address != NULL)? pnlocal : 0);
2785 s = ss = US"235 Authentication succeeded";
2786 authenticated_by = au;
2787 break;
2788 }
2789
2790 /* Authentication succeeded, but we failed to expand the set_id string.
2791 Treat this as a temporary error. */
2792
2793 auth_defer_msg = expand_string_message;
2794 /* Fall through */
2795
2796 case DEFER:
2797 s = string_sprintf("435 Unable to authenticate at present%s",
2798 auth_defer_user_msg);
2799 ss = string_sprintf("435 Unable to authenticate at present%s: %s",
2800 set_id, auth_defer_msg);
2801 break;
2802
2803 case BAD64:
2804 s = ss = US"501 Invalid base64 data";
2805 break;
2806
2807 case CANCELLED:
2808 s = ss = US"501 Authentication cancelled";
2809 break;
2810
2811 case UNEXPECTED:
2812 s = ss = US"553 Initial data not expected";
2813 break;
2814
2815 case FAIL:
2816 s = US"535 Incorrect authentication data";
2817 ss = string_sprintf("535 Incorrect authentication data%s", set_id);
2818 break;
2819
2820 default:
2821 s = US"435 Internal error";
2822 ss = string_sprintf("435 Internal error%s: return %d from authentication "
2823 "check", set_id, c);
2824 break;
2825 }
2826
2827 smtp_printf("%s\r\n", s);
2828 if (c != OK)
2829 log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
2830 au->name, host_and_ident(FALSE), ss);
2831
2832 break; /* AUTH_CMD */
2833
2834 /* The HELO/EHLO commands are permitted to appear in the middle of a
2835 session as well as at the beginning. They have the effect of a reset in
2836 addition to their other functions. Their absence at the start cannot be
2837 taken to be an error.
2838
2839 RFC 2821 says:
2840
2841 If the EHLO command is not acceptable to the SMTP server, 501, 500,
2842 or 502 failure replies MUST be returned as appropriate. The SMTP
2843 server MUST stay in the same state after transmitting these replies
2844 that it was in before the EHLO was received.
2845
2846 Therefore, we do not do the reset until after checking the command for
2847 acceptability. This change was made for Exim release 4.11. Previously
2848 it did the reset first. */
2849
2850 case HELO_CMD:
b4ed4da0 2851 HAD(SCH_HELO);
059ec3d9
PH
2852 hello = US"HELO";
2853 esmtp = FALSE;
2854 goto HELO_EHLO;
2855
2856 case EHLO_CMD:
b4ed4da0 2857 HAD(SCH_EHLO);
059ec3d9
PH
2858 hello = US"EHLO";
2859 esmtp = TRUE;
2860
2861 HELO_EHLO: /* Common code for HELO and EHLO */
2862 cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE;
2863 cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE;
2864
2865 /* Reject the HELO if its argument was invalid or non-existent. A
2866 successful check causes the argument to be saved in malloc store. */
2867
ca86f471 2868 if (!check_helo(smtp_cmd_data))
059ec3d9
PH
2869 {
2870 smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello);
2871
2872 log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically "
2873 "invalid argument(s): %s", hello, host_and_ident(FALSE),
3ee512ff
PH
2874 (*smtp_cmd_argument == 0)? US"(no argument given)" :
2875 string_printing(smtp_cmd_argument));
059ec3d9
PH
2876
2877 if (++synprot_error_count > smtp_max_synprot_errors)
2878 {
2879 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
2880 "syntax or protocol errors (last command was \"%s\")",
3ee512ff 2881 host_and_ident(FALSE), smtp_cmd_buffer);
059ec3d9
PH
2882 done = 1;
2883 }
2884
2885 break;
2886 }
2887
2888 /* If sender_host_unknown is true, we have got here via the -bs interface,
2889 not called from inetd. Otherwise, we are running an IP connection and the
2890 host address will be set. If the helo name is the primary name of this
2891 host and we haven't done a reverse lookup, force one now. If helo_required
2892 is set, ensure that the HELO name matches the actual host. If helo_verify
2893 is set, do the same check, but softly. */
2894
2895 if (!sender_host_unknown)
2896 {
2897 BOOL old_helo_verified = helo_verified;
ca86f471 2898 uschar *p = smtp_cmd_data;
059ec3d9
PH
2899
2900 while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
2901 *p = 0;
2902
2903 /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
2904 because otherwise the log can be confusing. */
2905
2906 if (sender_host_name == NULL &&
2907 (deliver_domain = sender_helo_name, /* set $domain */
2908 match_isinlist(sender_helo_name, &helo_lookup_domains, 0,
2909 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL)) == OK)
2910 (void)host_name_lookup();
2911
2912 /* Rebuild the fullhost info to include the HELO name (and the real name
2913 if it was looked up.) */
2914
2915 host_build_sender_fullhost(); /* Rebuild */
2916 set_process_info("handling%s incoming connection from %s",
2917 (tls_active >= 0)? " TLS" : "", host_and_ident(FALSE));
2918
2919 /* Verify if configured. This doesn't give much security, but it does
d7b47fd0
PH
2920 make some people happy to be able to do it. If helo_required is set,
2921 (host matches helo_verify_hosts) failure forces rejection. If helo_verify
2922 is set (host matches helo_try_verify_hosts), it does not. This is perhaps
2923 now obsolescent, since the verification can now be requested selectively
2924 at ACL time. */
059ec3d9 2925
d7b47fd0 2926 helo_verified = helo_verify_failed = FALSE;
059ec3d9
PH
2927 if (helo_required || helo_verify)
2928 {
d7b47fd0 2929 BOOL tempfail = !smtp_verify_helo();
059ec3d9
PH
2930 if (!helo_verified)
2931 {
2932 if (helo_required)
2933 {
2934 smtp_printf("%d %s argument does not match calling host\r\n",
2935 tempfail? 451 : 550, hello);
2936 log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s",
2937 tempfail? "temporarily " : "",
2938 hello, sender_helo_name, host_and_ident(FALSE));
2939 helo_verified = old_helo_verified;
2940 break; /* End of HELO/EHLO processing */
2941 }
2942 HDEBUG(D_all) debug_printf("%s verification failed but host is in "
2943 "helo_try_verify_hosts\n", hello);
2944 }
2945 }
2946 }
2947
8523533c
TK
2948#ifdef EXPERIMENTAL_SPF
2949 /* set up SPF context */
2950 spf_init(sender_helo_name, sender_host_address);
2951#endif
2952
a14e5636
PH
2953 /* Apply an ACL check if one is defined; afterwards, recheck
2954 synchronization in case the client started sending in a delay. */
059ec3d9
PH
2955
2956 if (acl_smtp_helo != NULL)
2957 {
64ffc24f 2958 rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, &user_msg, &log_msg);
059ec3d9
PH
2959 if (rc != OK)
2960 {
2961 done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg);
2962 sender_helo_name = NULL;
2963 host_build_sender_fullhost(); /* Rebuild */
2964 break;
2965 }
a14e5636 2966 else if (!check_sync()) goto SYNC_FAILURE;
059ec3d9
PH
2967 }
2968
4e88a19f
PH
2969 /* Generate an OK reply. The default string includes the ident if present,
2970 and also the IP address if present. Reflecting back the ident is intended
2971 as a deterrent to mail forgers. For maximum efficiency, and also because
2972 some broken systems expect each response to be in a single packet, arrange
2973 that the entire reply is sent in one write(). */
059ec3d9
PH
2974
2975 auth_advertised = FALSE;
2976 pipelining_advertised = FALSE;
2977 #ifdef SUPPORT_TLS
2978 tls_advertised = FALSE;
2979 #endif
2980
d6a96edc 2981 smtp_code = US"250 "; /* Default response code plus space*/
4e88a19f
PH
2982 if (user_msg == NULL)
2983 {
2984 s = string_sprintf("%.3s %s Hello %s%s%s",
2985 smtp_code,
2986 smtp_active_hostname,
2987 (sender_ident == NULL)? US"" : sender_ident,
2988 (sender_ident == NULL)? US"" : US" at ",
2989 (sender_host_name == NULL)? sender_helo_name : sender_host_name);
2990
2991 ptr = Ustrlen(s);
2992 size = ptr + 1;
059ec3d9 2993
4e88a19f
PH
2994 if (sender_host_address != NULL)
2995 {
2996 s = string_cat(s, &size, &ptr, US" [", 2);
2997 s = string_cat(s, &size, &ptr, sender_host_address,
2998 Ustrlen(sender_host_address));
2999 s = string_cat(s, &size, &ptr, US"]", 1);
3000 }
3001 }
3002
d6a96edc
PH
3003 /* A user-supplied EHLO greeting may not contain more than one line. Note
3004 that the code returned by smtp_message_code() includes the terminating
3005 whitespace character. */
059ec3d9 3006
4e88a19f 3007 else
059ec3d9 3008 {
4e88a19f 3009 char *ss;
d6a96edc 3010 int codelen = 4;
4e88a19f 3011 smtp_message_code(&smtp_code, &codelen, &user_msg, NULL);
d6a96edc 3012 s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg);
4e88a19f
PH
3013 if ((ss = strpbrk(CS s, "\r\n")) != NULL)
3014 {
3015 log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain "
3016 "newlines: message truncated: %s", string_printing(s));
3017 *ss = 0;
3018 }
3019 ptr = Ustrlen(s);
3020 size = ptr + 1;
059ec3d9
PH
3021 }
3022
3023 s = string_cat(s, &size, &ptr, US"\r\n", 2);
3024
3025 /* If we received EHLO, we must create a multiline response which includes
3026 the functions supported. */
3027
3028 if (esmtp)
3029 {
3030 s[3] = '-';
3031
3032 /* I'm not entirely happy with this, as an MTA is supposed to check
3033 that it has enough room to accept a message of maximum size before
3034 it sends this. However, there seems little point in not sending it.
3035 The actual size check happens later at MAIL FROM time. By postponing it
3036 till then, VRFY and EXPN can be used after EHLO when space is short. */
3037
3038 if (thismessage_size_limit > 0)
3039 {
4e88a19f
PH
3040 sprintf(CS big_buffer, "%.3s-SIZE %d\r\n", smtp_code,
3041 thismessage_size_limit);
059ec3d9
PH
3042 s = string_cat(s, &size, &ptr, big_buffer, Ustrlen(big_buffer));
3043 }
3044 else
3045 {
4e88a19f
PH
3046 s = string_cat(s, &size, &ptr, smtp_code, 3);
3047 s = string_cat(s, &size, &ptr, US"-SIZE\r\n", 7);
059ec3d9
PH
3048 }
3049
3050 /* Exim does not do protocol conversion or data conversion. It is 8-bit
3051 clean; if it has an 8-bit character in its hand, it just sends it. It
3052 cannot therefore specify 8BITMIME and remain consistent with the RFCs.
3053 However, some users want this option simply in order to stop MUAs
3054 mangling messages that contain top-bit-set characters. It is therefore
3055 provided as an option. */
3056
3057 if (accept_8bitmime)
4e88a19f
PH
3058 {
3059 s = string_cat(s, &size, &ptr, smtp_code, 3);
3060 s = string_cat(s, &size, &ptr, US"-8BITMIME\r\n", 11);
3061 }
059ec3d9
PH
3062
3063 /* Advertise ETRN if there's an ACL checking whether a host is
3064 permitted to issue it; a check is made when any host actually tries. */
3065
3066 if (acl_smtp_etrn != NULL)
3067 {
4e88a19f
PH
3068 s = string_cat(s, &size, &ptr, smtp_code, 3);
3069 s = string_cat(s, &size, &ptr, US"-ETRN\r\n", 7);
059ec3d9
PH
3070 }
3071
3072 /* Advertise EXPN if there's an ACL checking whether a host is
3073 permitted to issue it; a check is made when any host actually tries. */
3074
3075 if (acl_smtp_expn != NULL)
3076 {
4e88a19f
PH
3077 s = string_cat(s, &size, &ptr, smtp_code, 3);
3078 s = string_cat(s, &size, &ptr, US"-EXPN\r\n", 7);
059ec3d9
PH
3079 }
3080
3081 /* Exim is quite happy with pipelining, so let the other end know that
3082 it is safe to use it, unless advertising is disabled. */
3083
cf8b11a5
PH
3084 if (pipelining_enable &&
3085 verify_check_host(&pipelining_advertise_hosts) == OK)
059ec3d9 3086 {
4e88a19f
PH
3087 s = string_cat(s, &size, &ptr, smtp_code, 3);
3088 s = string_cat(s, &size, &ptr, US"-PIPELINING\r\n", 13);
059ec3d9
PH
3089 sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
3090 pipelining_advertised = TRUE;
3091 }
3092
3093 /* If any server authentication mechanisms are configured, advertise
3094 them if the current host is in auth_advertise_hosts. The problem with
3095 advertising always is that some clients then require users to
3096 authenticate (and aren't configurable otherwise) even though it may not
3097 be necessary (e.g. if the host is in host_accept_relay).
3098
3099 RFC 2222 states that SASL mechanism names contain only upper case
3100 letters, so output the names in upper case, though we actually recognize
3101 them in either case in the AUTH command. */
3102
3103 if (auths != NULL)
3104 {
3105 if (verify_check_host(&auth_advertise_hosts) == OK)
3106 {
3107 auth_instance *au;
3108 BOOL first = TRUE;
3109 for (au = auths; au != NULL; au = au->next)
3110 {
3111 if (au->server && (au->advertise_condition == NULL ||
3112 expand_check_condition(au->advertise_condition, au->name,
3113 US"authenticator")))
3114 {
3115 int saveptr;
3116 if (first)
3117 {
4e88a19f
PH
3118 s = string_cat(s, &size, &ptr, smtp_code, 3);
3119 s = string_cat(s, &size, &ptr, US"-AUTH", 5);
059ec3d9
PH
3120 first = FALSE;
3121 auth_advertised = TRUE;
3122 }
3123 saveptr = ptr;
3124 s = string_cat(s, &size, &ptr, US" ", 1);
3125 s = string_cat(s, &size, &ptr, au->public_name,
3126 Ustrlen(au->public_name));
3127 while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]);
3128 au->advertised = TRUE;
3129 }
3130 else au->advertised = FALSE;
3131 }
3132 if (!first) s = string_cat(s, &size, &ptr, US"\r\n", 2);
3133 }
3134 }
3135
3136 /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
3137 if it has been included in the binary, and the host matches
3138 tls_advertise_hosts. We must *not* advertise if we are already in a
3139 secure connection. */
3140
3141 #ifdef SUPPORT_TLS
3142 if (tls_active < 0 &&
3143 verify_check_host(&tls_advertise_hosts) != FAIL)
3144 {
4e88a19f
PH
3145 s = string_cat(s, &size, &ptr, smtp_code, 3);
3146 s = string_cat(s, &size, &ptr, US"-STARTTLS\r\n", 11);
059ec3d9
PH
3147 tls_advertised = TRUE;
3148 }
3149 #endif
3150
3151 /* Finish off the multiline reply with one that is always available. */
3152
4e88a19f
PH
3153 s = string_cat(s, &size, &ptr, smtp_code, 3);
3154 s = string_cat(s, &size, &ptr, US" HELP\r\n", 7);
059ec3d9
PH
3155 }
3156
3157 /* Terminate the string (for debug), write it, and note that HELO/EHLO
3158 has been seen. */
3159
3160 s[ptr] = 0;
3161
3162 #ifdef SUPPORT_TLS
3163 if (tls_active >= 0) (void)tls_write(s, ptr); else
3164 #endif
3165
f1e894f3 3166 (void)fwrite(s, 1, ptr, smtp_out);
898d150f
PH
3167 DEBUG(D_receive)
3168 {
3169 uschar *cr;
3170 while ((cr = Ustrchr(s, '\r')) != NULL) /* lose CRs */
3171 memmove(cr, cr + 1, (ptr--) - (cr - s));
3172 debug_printf("SMTP>> %s", s);
3173 }
059ec3d9 3174 helo_seen = TRUE;
4e88a19f
PH
3175
3176 /* Reset the protocol and the state, abandoning any previous message. */
3177
3178 received_protocol = (esmtp?
3179 protocols[pextend +
3180 ((sender_host_authenticated != NULL)? pauthed : 0) +
3181 ((tls_active >= 0)? pcrpted : 0)]
3182 :
3183 protocols[pnormal + ((tls_active >= 0)? pcrpted : 0)])
3184 +
3185 ((sender_host_address != NULL)? pnlocal : 0);
3186
3187 smtp_reset(reset_point);
3188 toomany = FALSE;
059ec3d9
PH
3189 break; /* HELO/EHLO */
3190
3191
3192 /* The MAIL command requires an address as an operand. All we do
3193 here is to parse it for syntactic correctness. The form "<>" is
3194 a special case which converts into an empty string. The start/end
3195 pointers in the original are not used further for this address, as
3196 it is the canonical extracted address which is all that is kept. */
3197
3198 case MAIL_CMD:
b4ed4da0 3199 HAD(SCH_MAIL);
059ec3d9
PH
3200 smtp_mailcmd_count++; /* Count for limit and ratelimit */
3201 was_rej_mail = TRUE; /* Reset if accepted */
3202
3203 if (helo_required && !helo_seen)
3204 {
3205 smtp_printf("503 HELO or EHLO required\r\n");
3206 log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
3207 "HELO/EHLO given", host_and_ident(FALSE));
3208 break;
3209 }
3210
3211 if (sender_address != NULL)
3212 {
3213 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3214 US"sender already given");
3215 break;
3216 }
3217
ca86f471 3218 if (smtp_cmd_data[0] == 0)
059ec3d9
PH
3219 {
3220 done = synprot_error(L_smtp_protocol_error, 501, NULL,
3221 US"MAIL must have an address operand");
3222 break;
3223 }
3224
3225 /* Check to see if the limit for messages per connection would be
3226 exceeded by accepting further messages. */
3227
3228 if (smtp_accept_max_per_connection > 0 &&
3229 smtp_mailcmd_count > smtp_accept_max_per_connection)
3230 {
3231 smtp_printf("421 too many messages in this connection\r\n");
3232 log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many "
3233 "messages in one connection", host_and_ident(TRUE));
3234 break;
3235 }
3236
3237 /* Reset for start of message - even if this is going to fail, we
3238 obviously need to throw away any previous data. */
3239
3240 smtp_reset(reset_point);
3241 toomany = FALSE;
3242 sender_data = recipient_data = NULL;
3243
3244 /* Loop, checking for ESMTP additions to the MAIL FROM command. */
3245
3246 if (esmtp) for(;;)
3247 {
3248 uschar *name, *value, *end;
3249 unsigned long int size;
3250
3251 if (!extract_option(&name, &value)) break;
3252
3253 /* Handle SIZE= by reading the value. We don't do the check till later,
3254 in order to be able to log the sender address on failure. */
3255
3256 if (strcmpic(name, US"SIZE") == 0 &&
a4dc33a8 3257 ((size = Ustrtoul(value, &end, 10)), *end == 0))
059ec3d9
PH
3258 {
3259 if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
3260 size = INT_MAX;
3261 message_size = (int)size;
3262 }
3263
3264 /* If this session was initiated with EHLO and accept_8bitmime is set,
3265 Exim will have indicated that it supports the BODY=8BITMIME option. In
3266 fact, it does not support this according to the RFCs, in that it does not
3267 take any special action for forwarding messages containing 8-bit
3268 characters. That is why accept_8bitmime is not the default setting, but
3269 some sites want the action that is provided. We recognize both "8BITMIME"
3270 and "7BIT" as body types, but take no action. */
3271
3272 else if (accept_8bitmime && strcmpic(name, US"BODY") == 0 &&
3273 (strcmpic(value, US"8BITMIME") == 0 ||
3274 strcmpic(value, US"7BIT") == 0)) {}
3275
3276 /* Handle the AUTH extension. If the value given is not "<>" and either
3277 the ACL says "yes" or there is no ACL but the sending host is
3278 authenticated, we set it up as the authenticated sender. However, if the
3279 authenticator set a condition to be tested, we ignore AUTH on MAIL unless
3280 the condition is met. The value of AUTH is an xtext, which means that +,
3281 = and cntrl chars are coded in hex; however "<>" is unaffected by this
3282 coding. */
3283
3284 else if (strcmpic(name, US"AUTH") == 0)
3285 {
3286 if (Ustrcmp(value, "<>") != 0)
3287 {
3288 int rc;
3289 uschar *ignore_msg;
3290
3291 if (auth_xtextdecode(value, &authenticated_sender) < 0)
3292 {
3293 /* Put back terminator overrides for error message */
3294 name[-1] = ' ';
3295 value[-1] = '=';
3296 done = synprot_error(L_smtp_syntax_error, 501, NULL,
3297 US"invalid data for AUTH");
3298 goto COMMAND_LOOP;
3299 }
3300
3301 if (acl_smtp_mailauth == NULL)
3302 {
3303 ignore_msg = US"client not authenticated";
3304 rc = (sender_host_authenticated != NULL)? OK : FAIL;
3305 }
3306 else
3307 {
3308 ignore_msg = US"rejected by ACL";
3309 rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth,
3310 &user_msg, &log_msg);
3311 }
3312
3313 switch (rc)
3314 {
3315 case OK:
3316 if (authenticated_by == NULL ||
3317 authenticated_by->mail_auth_condition == NULL ||
3318 expand_check_condition(authenticated_by->mail_auth_condition,
3319 authenticated_by->name, US"authenticator"))
3320 break; /* Accept the AUTH */
3321
3322 ignore_msg = US"server_mail_auth_condition failed";
3323 if (authenticated_id != NULL)
3324 ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"",
3325 ignore_msg, authenticated_id);
3326
3327 /* Fall through */
3328
3329 case FAIL:
3330 authenticated_sender = NULL;
3331 log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)",
3332 value, host_and_ident(TRUE), ignore_msg);
3333 break;
3334
3335 /* Should only get DEFER or ERROR here. Put back terminator
3336 overrides for error message */
3337
3338 default:
3339 name[-1] = ' ';
3340 value[-1] = '=';
3341 (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg,
3342 log_msg);
3343 goto COMMAND_LOOP;
3344 }
3345 }
3346 }
3347
3348 /* Unknown option. Stick back the terminator characters and break
3349 the loop. An error for a malformed address will occur. */
3350
3351 else
3352 {
3353 name[-1] = ' ';
3354 value[-1] = '=';
3355 break;
3356 }
3357 }
3358
3359 /* If we have passed the threshold for rate limiting, apply the current
3360 delay, and update it for next time, provided this is a limited host. */
3361
3362 if (smtp_mailcmd_count > smtp_rlm_threshold &&
3363 verify_check_host(&smtp_ratelimit_hosts) == OK)
3364 {
3365 DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n",
3366 smtp_delay_mail/1000.0);
3367 millisleep((int)smtp_delay_mail);
3368 smtp_delay_mail *= smtp_rlm_factor;
3369 if (smtp_delay_mail > (double)smtp_rlm_limit)
3370 smtp_delay_mail = (double)smtp_rlm_limit;
3371 }
3372
3373 /* Now extract the address, first applying any SMTP-time rewriting. The
3374 TRUE flag allows "<>" as a sender address. */
3375
3376 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
3377 rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
3378 global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
3379
3380 /* rfc821_domains = TRUE; << no longer needed */
3381 raw_sender =
3382 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
3383 TRUE);
3384 /* rfc821_domains = FALSE; << no longer needed */
3385
3386 if (raw_sender == NULL)
3387 {
ca86f471 3388 done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);
059ec3d9
PH
3389 break;
3390 }
3391
3392 sender_address = raw_sender;
3393
3394 /* If there is a configured size limit for mail, check that this message
3395 doesn't exceed it. The check is postponed to this point so that the sender
3396 can be logged. */
3397
3398 if (thismessage_size_limit > 0 && message_size > thismessage_size_limit)
3399 {
3400 smtp_printf("552 Message size exceeds maximum permitted\r\n");
3401 log_write(L_size_reject,
3402 LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: "
3403 "message too big: size%s=%d max=%d",
3404 sender_address,
3405 host_and_ident(TRUE),
3406 (message_size == INT_MAX)? ">" : "",
3407 message_size,
3408 thismessage_size_limit);
3409 sender_address = NULL;
3410 break;
3411 }
3412
3413 /* Check there is enough space on the disk unless configured not to.
3414 When smtp_check_spool_space is set, the check is for thismessage_size_limit
3415 plus the current message - i.e. we accept the message only if it won't
3416 reduce the space below the threshold. Add 5000 to the size to allow for
3417 overheads such as the Received: line and storing of recipients, etc.
3418 By putting the check here, even when SIZE is not given, it allow VRFY
3419 and EXPN etc. to be used when space is short. */
3420
3421 if (!receive_check_fs(
3422 (smtp_check_spool_space && message_size >= 0)?
3423 message_size + 5000 : 0))
3424 {
3425 smtp_printf("452 Space shortage, please try later\r\n");
3426 sender_address = NULL;
3427 break;
3428 }
3429
3430 /* If sender_address is unqualified, reject it, unless this is a locally
3431 generated message, or the sending host or net is permitted to send
3432 unqualified addresses - typically local machines behaving as MUAs -
3433 in which case just qualify the address. The flag is set above at the start
3434 of the SMTP connection. */
3435
3436 if (sender_domain == 0 && sender_address[0] != 0)
3437 {
3438 if (allow_unqualified_sender)
3439 {
3440 sender_domain = Ustrlen(sender_address) + 1;
3441 sender_address = rewrite_address_qualify(sender_address, FALSE);
3442 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
3443 raw_sender);
3444 }
3445 else
3446 {
3447 smtp_printf("501 %s: sender address must contain a domain\r\n",
ca86f471 3448 smtp_cmd_data);
059ec3d9
PH
3449 log_write(L_smtp_syntax_error,
3450 LOG_MAIN|LOG_REJECT,
3451 "unqualified sender rejected: <%s> %s%s",
3452 raw_sender,
3453 host_and_ident(TRUE),
3454 host_lookup_msg);
3455 sender_address = NULL;
3456 break;
3457 }
3458 }
3459
a14e5636
PH
3460 /* Apply an ACL check if one is defined, before responding. Afterwards,
3461 when pipelining is not advertised, do another sync check in case the ACL
3462 delayed and the client started sending in the meantime. */
059ec3d9 3463
a14e5636
PH
3464 if (acl_smtp_mail == NULL) rc = OK; else
3465 {
3466 rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg);
3467 if (rc == OK && !pipelining_advertised && !check_sync())
3468 goto SYNC_FAILURE;
3469 }
059ec3d9
PH
3470
3471 if (rc == OK || rc == DISCARD)
3472 {
4e88a19f
PH
3473 if (user_msg == NULL) smtp_printf("250 OK\r\n");
3474 else smtp_user_msg(US"250", user_msg);
059ec3d9
PH
3475 smtp_delay_rcpt = smtp_rlr_base;
3476 recipients_discarded = (rc == DISCARD);
3477 was_rej_mail = FALSE;
3478 }
059ec3d9
PH
3479 else
3480 {
3481 done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg);
3482 sender_address = NULL;
3483 }
3484 break;
3485
3486
2679d413
PH
3487 /* The RCPT command requires an address as an operand. There may be any
3488 number of RCPT commands, specifying multiple recipients. We build them all
3489 into a data structure. The start/end values given by parse_extract_address
3490 are not used, as we keep only the extracted address. */
059ec3d9
PH
3491
3492 case RCPT_CMD:
b4ed4da0 3493 HAD(SCH_RCPT);
059ec3d9 3494 rcpt_count++;
2679d413 3495 was_rcpt = rcpt_in_progress = TRUE;
059ec3d9
PH
3496
3497 /* There must be a sender address; if the sender was rejected and
3498 pipelining was advertised, we assume the client was pipelining, and do not
3499 count this as a protocol error. Reset was_rej_mail so that further RCPTs
3500 get the same treatment. */
3501
3502 if (sender_address == NULL)
3503 {
3504 if (pipelining_advertised && last_was_rej_mail)
3505 {
3506 smtp_printf("503 sender not yet given\r\n");
3507 was_rej_mail = TRUE;
3508 }
3509 else
3510 {
3511 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3512 US"sender not yet given");
3513 was_rcpt = FALSE; /* Not a valid RCPT */
3514 }
3515 rcpt_fail_count++;
3516 break;
3517 }
3518
3519 /* Check for an operand */
3520
ca86f471 3521 if (smtp_cmd_data[0] == 0)
059ec3d9
PH
3522 {
3523 done = synprot_error(L_smtp_syntax_error, 501, NULL,
3524 US"RCPT must have an address operand");
3525 rcpt_fail_count++;
3526 break;
3527 }
3528
3529 /* Apply SMTP rewriting then extract the working address. Don't allow "<>"
3530 as a recipient address */
3531
3532 recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
3533 rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
3534 global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
3535
3536 /* rfc821_domains = TRUE; << no longer needed */
3537 recipient = parse_extract_address(recipient, &errmess, &start, &end,
3538 &recipient_domain, FALSE);
3539 /* rfc821_domains = FALSE; << no longer needed */
3540
3541 if (recipient == NULL)
3542 {
ca86f471 3543 done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess);
059ec3d9
PH
3544 rcpt_fail_count++;
3545 break;
3546 }
3547
3548 /* If the recipient address is unqualified, reject it, unless this is a
3549 locally generated message. However, unqualified addresses are permitted
3550 from a configured list of hosts and nets - typically when behaving as
3551 MUAs rather than MTAs. Sad that SMTP is used for both types of traffic,
3552 really. The flag is set at the start of the SMTP connection.
3553
3554 RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always
3555 assumed this meant "reserved local part", but the revision of RFC 821 and
3556 friends now makes it absolutely clear that it means *mailbox*. Consequently
3557 we must always qualify this address, regardless. */
3558
3559 if (recipient_domain == 0)
3560 {
3561 if (allow_unqualified_recipient ||
3562 strcmpic(recipient, US"postmaster") == 0)
3563 {
3564 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
3565 recipient);
3566 recipient_domain = Ustrlen(recipient) + 1;
3567 recipient = rewrite_address_qualify(recipient, TRUE);
3568 }
3569 else
3570 {
3571 rcpt_fail_count++;
3572 smtp_printf("501 %s: recipient address must contain a domain\r\n",
ca86f471 3573 smtp_cmd_data);
059ec3d9
PH
3574 log_write(L_smtp_syntax_error,
3575 LOG_MAIN|LOG_REJECT, "unqualified recipient rejected: "
3576 "<%s> %s%s", recipient, host_and_ident(TRUE),
3577 host_lookup_msg);
3578 break;
3579 }
3580 }
3581
3582 /* Check maximum allowed */
3583
3584 if (rcpt_count > recipients_max && recipients_max > 0)
3585 {
3586 if (recipients_max_reject)
3587 {
3588 rcpt_fail_count++;
3589 smtp_printf("552 too many recipients\r\n");
3590 if (!toomany)
3591 log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message "
3592 "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE));
3593 }
3594 else
3595 {
3596 rcpt_defer_count++;
3597 smtp_printf("452 too many recipients\r\n");
3598 if (!toomany)
3599 log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess "
3600 "temporarily rejected: sender=<%s> %s", sender_address,
3601 host_and_ident(TRUE));
3602 }
3603
3604 toomany = TRUE;
3605 break;
3606 }
3607
3608 /* If we have passed the threshold for rate limiting, apply the current
3609 delay, and update it for next time, provided this is a limited host. */
3610
3611 if (rcpt_count > smtp_rlr_threshold &&
3612 verify_check_host(&smtp_ratelimit_hosts) == OK)
3613 {
3614 DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n",
3615 smtp_delay_rcpt/1000.0);
3616 millisleep((int)smtp_delay_rcpt);
3617 smtp_delay_rcpt *= smtp_rlr_factor;
3618 if (smtp_delay_rcpt > (double)smtp_rlr_limit)
3619 smtp_delay_rcpt = (double)smtp_rlr_limit;
3620 }
3621
3622 /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
a14e5636
PH
3623 for them. Otherwise, check the access control list for this recipient. As
3624 there may be a delay in this, re-check for a synchronization error
3625 afterwards, unless pipelining was advertised. */
059ec3d9 3626
a14e5636
PH
3627 if (recipients_discarded) rc = DISCARD; else
3628 {
3629 rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg,
3630 &log_msg);
3631 if (rc == OK && !pipelining_advertised && !check_sync())
3632 goto SYNC_FAILURE;
3633 }
059ec3d9
PH
3634
3635 /* The ACL was happy */
3636
3637 if (rc == OK)
3638 {
4e88a19f
PH
3639 if (user_msg == NULL) smtp_printf("250 Accepted\r\n");
3640 else smtp_user_msg(US"250", user_msg);
059ec3d9
PH
3641 receive_add_recipient(recipient, -1);
3642 }
3643
3644 /* The recipient was discarded */
3645
3646 else if (rc == DISCARD)
3647 {
4e88a19f
PH
3648 if (user_msg == NULL) smtp_printf("250 Accepted\r\n");
3649 else smtp_user_msg(US"250", user_msg);
059ec3d9
PH
3650 rcpt_fail_count++;
3651 discarded = TRUE;
3652 log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> rejected RCPT %s: "
3653 "discarded by %s ACL%s%s", host_and_ident(TRUE),
3654 (sender_address_unrewritten != NULL)?
3655 sender_address_unrewritten : sender_address,
3ee512ff 3656 smtp_cmd_argument, recipients_discarded? "MAIL" : "RCPT",
059ec3d9
PH
3657 (log_msg == NULL)? US"" : US": ",
3658 (log_msg == NULL)? US"" : log_msg);
3659 }
3660
3661 /* Either the ACL failed the address, or it was deferred. */
3662
3663 else
3664 {
3665 if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++;
3666 done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg);
3667 }
3668 break;
3669
3670
3671 /* The DATA command is legal only if it follows successful MAIL FROM
3672 and RCPT TO commands. However, if pipelining is advertised, a bad DATA is
3673 not counted as a protocol error if it follows RCPT (which must have been
3674 rejected if there are no recipients.) This function is complete when a
3675 valid DATA command is encountered.
3676
3677 Note concerning the code used: RFC 2821 says this:
3678
3679 - If there was no MAIL, or no RCPT, command, or all such commands
3680 were rejected, the server MAY return a "command out of sequence"
3681 (503) or "no valid recipients" (554) reply in response to the
3682 DATA command.
3683
3684 The example in the pipelining RFC 2920 uses 554, but I use 503 here
2679d413
PH
3685 because it is the same whether pipelining is in use or not.
3686
3687 If all the RCPT commands that precede DATA provoked the same error message
3688 (often indicating some kind of system error), it is helpful to include it
3689 with the DATA rejection (an idea suggested by Tony Finch). */
059ec3d9
PH
3690
3691 case DATA_CMD:
b4ed4da0 3692 HAD(SCH_DATA);
059ec3d9
PH
3693 if (!discarded && recipients_count <= 0)
3694 {
2679d413
PH
3695 if (rcpt_smtp_response_same && rcpt_smtp_response != NULL)
3696 {
3697 uschar *code = US"503";
3698 int len = Ustrlen(rcpt_smtp_response);
3699 smtp_respond(code, 3, FALSE, US"All RCPT commands were rejected with "
3700 "this error:");
3701 /* Responses from smtp_printf() will have \r\n on the end */
3702 if (len > 2 && rcpt_smtp_response[len-2] == '\r')
3703 rcpt_smtp_response[len-2] = 0;
3704 smtp_respond(code, 3, FALSE, rcpt_smtp_response);
3705 }
059ec3d9 3706 if (pipelining_advertised && last_was_rcpt)
2679d413 3707 smtp_printf("503 Valid RCPT command must precede DATA\r\n");
059ec3d9
PH
3708 else
3709 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3710 US"valid RCPT command must precede DATA");
3711 break;
3712 }
3713
3714 if (toomany && recipients_max_reject)
3715 {
3716 sender_address = NULL; /* This will allow a new MAIL without RSET */
3717 sender_address_unrewritten = NULL;
3718 smtp_printf("554 Too many recipients\r\n");
3719 break;
3720 }
8e669ac1 3721
a14e5636
PH
3722 /* If there is an ACL, re-check the synchronization afterwards, since the
3723 ACL may have delayed. */
3724
5be20824 3725 if (acl_smtp_predata == NULL) rc = OK; else
8e669ac1 3726 {
5be20824 3727 enable_dollar_recipients = TRUE;
8e669ac1 3728 rc = acl_check(ACL_WHERE_PREDATA, NULL, acl_smtp_predata, &user_msg,
5be20824
PH
3729 &log_msg);
3730 enable_dollar_recipients = FALSE;
a14e5636 3731 if (rc == OK && !check_sync()) goto SYNC_FAILURE;
5be20824 3732 }
059ec3d9
PH
3733
3734 if (rc == OK)
3735 {
4e88a19f
PH
3736 if (user_msg == NULL)
3737 smtp_printf("354 Enter message, ending with \".\" on a line by itself\r\n");
3738 else smtp_user_msg(US"354", user_msg);
059ec3d9
PH
3739 done = 3;
3740 message_ended = END_NOTENDED; /* Indicate in middle of data */
3741 }
3742
3743 /* Either the ACL failed the address, or it was deferred. */
3744
3745 else
3746 done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg);
059ec3d9
PH
3747 break;
3748
3749
3750 case VRFY_CMD:
b4ed4da0 3751 HAD(SCH_VRFY);
64ffc24f 3752 rc = acl_check(ACL_WHERE_VRFY, NULL, acl_smtp_vrfy, &user_msg, &log_msg);
059ec3d9
PH
3753 if (rc != OK)
3754 done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg);
3755 else
3756 {
3757 uschar *address;
3758 uschar *s = NULL;
3759
3760 /* rfc821_domains = TRUE; << no longer needed */
ca86f471 3761 address = parse_extract_address(smtp_cmd_data, &errmess, &start, &end,
059ec3d9
PH
3762 &recipient_domain, FALSE);
3763 /* rfc821_domains = FALSE; << no longer needed */
3764
3765 if (address == NULL)
3766 s = string_sprintf("501 %s", errmess);
3767 else
3768 {
3769 address_item *addr = deliver_make_addr(address, FALSE);
3770 switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1,
4deaf07d 3771 -1, -1, NULL, NULL, NULL))
059ec3d9
PH
3772 {
3773 case OK:
3774 s = string_sprintf("250 <%s> is deliverable", address);
3775 break;
3776
3777 case DEFER:
81e509d7
PH
3778 s = (addr->user_message != NULL)?
3779 string_sprintf("451 <%s> %s", address, addr->user_message) :
059ec3d9
PH
3780 string_sprintf("451 Cannot resolve <%s> at this time", address);
3781 break;
3782
3783 case FAIL:
81e509d7
PH
3784 s = (addr->user_message != NULL)?
3785 string_sprintf("550 <%s> %s", address, addr->user_message) :
059ec3d9
PH
3786 string_sprintf("550 <%s> is not deliverable", address);
3787 log_write(0, LOG_MAIN, "VRFY failed for %s %s",
3ee512ff 3788 smtp_cmd_argument, host_and_ident(TRUE));
059ec3d9
PH
3789 break;
3790 }
3791 }
3792
3793 smtp_printf("%s\r\n", s);
3794 }
3795 break;
3796
3797
3798 case EXPN_CMD:
b4ed4da0 3799 HAD(SCH_EXPN);
64ffc24f 3800 rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg);
059ec3d9
PH
3801 if (rc != OK)
3802 done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg);
3803 else
3804 {
3805 BOOL save_log_testing_mode = log_testing_mode;
3806 address_test_mode = log_testing_mode = TRUE;
ca86f471 3807 (void) verify_address(deliver_make_addr(smtp_cmd_data, FALSE),
64ffc24f
PH
3808 smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1,
3809 NULL, NULL, NULL);
059ec3d9
PH
3810 address_test_mode = FALSE;
3811 log_testing_mode = save_log_testing_mode; /* true for -bh */
3812 }
3813 break;
3814
3815
3816 #ifdef SUPPORT_TLS
3817
3818 case STARTTLS_CMD:
b4ed4da0 3819 HAD(SCH_STARTTLS);
059ec3d9
PH
3820 if (!tls_advertised)
3821 {
3822 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3823 US"STARTTLS command used when not advertised");
3824 break;
3825 }
3826
3827 /* Apply an ACL check if one is defined */
3828
3829 if (acl_smtp_starttls != NULL)
3830 {
3831 rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls, &user_msg,
3832 &log_msg);
3833 if (rc != OK)
3834 {
3835 done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg);
3836 break;
3837 }
3838 }
3839
3840 /* RFC 2487 is not clear on when this command may be sent, though it
3841 does state that all information previously obtained from the client