Fix Proxy Protocol v2 handling
[exim.git] / src / src / smtp_in.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
bc338899 5/* Copyright (c) University of Cambridge 1995 - 2013 */
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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
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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
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97#ifdef EXPERIMENTAL_PROXY
98 PROXY_FAIL_IGNORE_CMD,
99#endif
100
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101 /* These are specials that don't correspond to actual commands */
102
103 EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD,
104 TOO_MANY_NONMAIL_CMD };
105
106
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107/* This is a convenience macro for adding the identity of an SMTP command
108to the circular buffer that holds a list of the last n received. */
109
110#define HAD(n) \
111 smtp_connection_had[smtp_ch_index++] = n; \
112 if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
113
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114
115/*************************************************
116* Local static variables *
117*************************************************/
118
119static auth_instance *authenticated_by;
120static BOOL auth_advertised;
121#ifdef SUPPORT_TLS
122static BOOL tls_advertised;
123#endif
124static BOOL esmtp;
125static BOOL helo_required = FALSE;
126static BOOL helo_verify = FALSE;
127static BOOL helo_seen;
128static BOOL helo_accept_junk;
129static BOOL count_nonmail;
130static BOOL pipelining_advertised;
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131static BOOL rcpt_smtp_response_same;
132static BOOL rcpt_in_progress;
059ec3d9 133static int nonmail_command_count;
8f128379 134static BOOL smtp_exit_function_called = 0;
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135static int synprot_error_count;
136static int unknown_command_count;
137static int sync_cmd_limit;
138static int smtp_write_error = 0;
139
2679d413 140static uschar *rcpt_smtp_response;
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141static uschar *smtp_data_buffer;
142static uschar *smtp_cmd_data;
143
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144/* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
145final fields of all except AUTH are forced TRUE at the start of a new message
146setup, to allow one of each between messages that is not counted as a nonmail
147command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to
148allow a new EHLO after starting up TLS.
149
150AUTH is "falsely" labelled as a mail command initially, so that it doesn't get
151counted. However, the flag is changed when AUTH is received, so that multiple
152failing AUTHs will eventually hit the limit. After a successful AUTH, another
153AUTH is already forbidden. After a TLS session is started, AUTH's flag is again
154forced TRUE, to allow for the re-authentication that can happen at that point.
155
156QUIT is also "falsely" labelled as a mail command so that it doesn't up the
157count of non-mail commands and possibly provoke an error. */
158
159static smtp_cmd_list cmd_list[] = {
160 { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */
161 { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE },
162 { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE },
163 { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
164 #ifdef SUPPORT_TLS
165 { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
166 #endif
167
168/* If you change anything above here, also fix the definitions below. */
169
170 { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE },
171 { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE },
172 { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE },
173 { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE },
174 { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE },
175 { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE },
176 { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE },
177 { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE },
178 { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE }
179};
180
181static smtp_cmd_list *cmd_list_end =
182 cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list);
183
184#define CMD_LIST_RSET 0
185#define CMD_LIST_HELO 1
186#define CMD_LIST_EHLO 2
187#define CMD_LIST_AUTH 3
188#define CMD_LIST_STARTTLS 4
189
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190/* This list of names is used for performing the smtp_no_mail logging action.
191It must be kept in step with the SCH_xxx enumerations. */
192
193static uschar *smtp_names[] =
194 {
195 US"NONE", US"AUTH", US"DATA", US"EHLO", US"ETRN", US"EXPN", US"HELO",
196 US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET", US"STARTTLS",
197 US"VRFY" };
198
059ec3d9 199static uschar *protocols[] = {
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200 US"local-smtp", /* HELO */
201 US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
202 US"local-esmtp", /* EHLO */
203 US"local-esmtps", /* EHLO->STARTTLS->EHLO */
204 US"local-esmtpa", /* EHLO->AUTH */
205 US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
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206 };
207
208#define pnormal 0
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209#define pextend 2
210#define pcrpted 1 /* added to pextend or pnormal */
211#define pauthed 2 /* added to pextend */
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212#define pnlocal 6 /* offset to remove "local" */
213
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214/* Sanity check and validate optional args to MAIL FROM: envelope */
215enum {
216 ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH,
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217#ifdef EXPERIMENTAL_PRDR
218 ENV_MAIL_OPT_PRDR,
219#endif
220 ENV_MAIL_OPT_NULL
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221 };
222typedef struct {
223 uschar * name; /* option requested during MAIL cmd */
224 int value; /* enum type */
225 BOOL need_value; /* TRUE requires value (name=value pair format)
226 FALSE is a singleton */
227 } env_mail_type_t;
228static env_mail_type_t env_mail_type_list[] = {
229 { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE },
230 { US"BODY", ENV_MAIL_OPT_BODY, TRUE },
231 { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE },
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232#ifdef EXPERIMENTAL_PRDR
233 { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE },
234#endif
235 { US"NULL", ENV_MAIL_OPT_NULL, FALSE }
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236 };
237
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238/* When reading SMTP from a remote host, we have to use our own versions of the
239C input-reading functions, in order to be able to flush the SMTP output only
240when about to read more data from the socket. This is the only way to get
241optimal performance when the client is using pipelining. Flushing for every
242command causes a separate packet and reply packet each time; saving all the
243responses up (when pipelining) combines them into one packet and one response.
244
245For simplicity, these functions are used for *all* SMTP input, not only when
246receiving over a socket. However, after setting up a secure socket (SSL), input
247is read via the OpenSSL library, and another set of functions is used instead
248(see tls.c).
249
250These functions are set in the receive_getc etc. variables and called with the
251same interface as the C functions. However, since there can only ever be
252one incoming SMTP call, we just use a single buffer and flags. There is no need
253to implement a complicated private FILE-like structure.*/
254
255static uschar *smtp_inbuffer;
256static uschar *smtp_inptr;
257static uschar *smtp_inend;
258static int smtp_had_eof;
259static int smtp_had_error;
260
261
262/*************************************************
263* SMTP version of getc() *
264*************************************************/
265
266/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
267it flushes the output, and refills the buffer, with a timeout. The signal
268handler is set appropriately by the calling function. This function is not used
269after a connection has negotated itself into an TLS/SSL state.
270
271Arguments: none
272Returns: the next character or EOF
273*/
274
275int
276smtp_getc(void)
277{
278if (smtp_inptr >= smtp_inend)
279 {
280 int rc, save_errno;
281 fflush(smtp_out);
282 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
283 rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size);
284 save_errno = errno;
285 alarm(0);
286 if (rc <= 0)
287 {
288 /* Must put the error text in fixed store, because this might be during
289 header reading, where it releases unused store above the header. */
290 if (rc < 0)
291 {
292 smtp_had_error = save_errno;
293 smtp_read_error = string_copy_malloc(
294 string_sprintf(" (error: %s)", strerror(save_errno)));
295 }
296 else smtp_had_eof = 1;
297 return EOF;
298 }
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299#ifndef DISABLE_DKIM
300 dkim_exim_verify_feed(smtp_inbuffer, rc);
301#endif
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302 smtp_inend = smtp_inbuffer + rc;
303 smtp_inptr = smtp_inbuffer;
304 }
305return *smtp_inptr++;
306}
307
308
309
310/*************************************************
311* SMTP version of ungetc() *
312*************************************************/
313
314/* Puts a character back in the input buffer. Only ever
315called once.
316
317Arguments:
318 ch the character
319
320Returns: the character
321*/
322
323int
324smtp_ungetc(int ch)
325{
326*(--smtp_inptr) = ch;
327return ch;
328}
329
330
331
332
333/*************************************************
334* SMTP version of feof() *
335*************************************************/
336
337/* Tests for a previous EOF
338
339Arguments: none
340Returns: non-zero if the eof flag is set
341*/
342
343int
344smtp_feof(void)
345{
346return smtp_had_eof;
347}
348
349
350
351
352/*************************************************
353* SMTP version of ferror() *
354*************************************************/
355
356/* Tests for a previous read error, and returns with errno
357restored to what it was when the error was detected.
358
359Arguments: none
360Returns: non-zero if the error flag is set
361*/
362
363int
364smtp_ferror(void)
365{
366errno = smtp_had_error;
367return smtp_had_error;
368}
369
370
371
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372/*************************************************
373* Test for characters in the SMTP buffer *
374*************************************************/
375
376/* Used at the end of a message
377
378Arguments: none
379Returns: TRUE/FALSE
380*/
381
382BOOL
383smtp_buffered(void)
384{
385return smtp_inptr < smtp_inend;
386}
387
388
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389
390/*************************************************
391* Write formatted string to SMTP channel *
392*************************************************/
393
394/* This is a separate function so that we don't have to repeat everything for
395TLS support or debugging. It is global so that the daemon and the
396authentication functions can use it. It does not return any error indication,
397because major problems such as dropped connections won't show up till an output
398flush for non-TLS connections. The smtp_fflush() function is available for
399checking that: for convenience, TLS output errors are remembered here so that
400they are also picked up later by smtp_fflush().
401
402Arguments:
403 format format string
404 ... optional arguments
405
406Returns: nothing
407*/
408
409void
1ba28e2b 410smtp_printf(const char *format, ...)
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411{
412va_list ap;
413
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414va_start(ap, format);
415smtp_vprintf(format, ap);
416va_end(ap);
417}
418
419/* This is split off so that verify.c:respond_printf() can, in effect, call
420smtp_printf(), bearing in mind that in C a vararg function can't directly
fb08281f 421call another vararg function, only a function which accepts a va_list. */
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422
423void
1ba28e2b 424smtp_vprintf(const char *format, va_list ap)
ce552449 425{
fb08281f
DW
426BOOL yield;
427
428yield = string_vformat(big_buffer, big_buffer_size, format, ap);
ce552449 429
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430DEBUG(D_receive)
431 {
fb08281f
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432 void *reset_point = store_get(0);
433 uschar *msg_copy, *cr, *end;
434 msg_copy = string_copy(big_buffer);
435 end = msg_copy + Ustrlen(msg_copy);
436 while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
437 memmove(cr, cr + 1, (end--) - cr);
438 debug_printf("SMTP>> %s", msg_copy);
439 store_reset(reset_point);
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440 }
441
fb08281f 442if (!yield)
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443 {
444 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
445 smtp_closedown(US"Unexpected error");
446 exim_exit(EXIT_FAILURE);
447 }
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PH
448
449/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
450have had the same. Note: this code is also present in smtp_respond(). It would
451be tidier to have it only in one place, but when it was added, it was easier to
452do it that way, so as not to have to mess with the code for the RCPT command,
453which sometimes uses smtp_printf() and sometimes smtp_respond(). */
454
455if (rcpt_in_progress)
456 {
457 if (rcpt_smtp_response == NULL)
458 rcpt_smtp_response = string_copy(big_buffer);
459 else if (rcpt_smtp_response_same &&
460 Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
461 rcpt_smtp_response_same = FALSE;
462 rcpt_in_progress = FALSE;
463 }
059ec3d9 464
2679d413 465/* Now write the string */
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466
467#ifdef SUPPORT_TLS
817d9f57 468if (tls_in.active >= 0)
059ec3d9 469 {
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JH
470 if (tls_write(TRUE, big_buffer, Ustrlen(big_buffer)) < 0)
471 smtp_write_error = -1;
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472 }
473else
474#endif
475
2679d413 476if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1;
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477}
478
479
480
481/*************************************************
482* Flush SMTP out and check for error *
483*************************************************/
484
485/* This function isn't currently used within Exim (it detects errors when it
486tries to read the next SMTP input), but is available for use in local_scan().
487For non-TLS connections, it flushes the output and checks for errors. For
488TLS-connections, it checks for a previously-detected TLS write error.
489
490Arguments: none
491Returns: 0 for no error; -1 after an error
492*/
493
494int
495smtp_fflush(void)
496{
817d9f57 497if (tls_in.active < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
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498return smtp_write_error;
499}
500
501
502
503/*************************************************
504* SMTP command read timeout *
505*************************************************/
506
507/* Signal handler for timing out incoming SMTP commands. This attempts to
508finish off tidily.
509
510Argument: signal number (SIGALRM)
511Returns: nothing
512*/
513
514static void
515command_timeout_handler(int sig)
516{
517sig = sig; /* Keep picky compilers happy */
518log_write(L_lost_incoming_connection,
519 LOG_MAIN, "SMTP command timeout on%s connection from %s",
817d9f57 520 (tls_in.active >= 0)? " TLS" : "",
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521 host_and_ident(FALSE));
522if (smtp_batched_input)
523 moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
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524smtp_notquit_exit(US"command-timeout", US"421",
525 US"%s: SMTP command timeout - closing connection", smtp_active_hostname);
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526exim_exit(EXIT_FAILURE);
527}
528
529
530
531/*************************************************
532* SIGTERM received *
533*************************************************/
534
535/* Signal handler for handling SIGTERM. Again, try to finish tidily.
536
537Argument: signal number (SIGTERM)
538Returns: nothing
539*/
540
541static void
542command_sigterm_handler(int sig)
543{
544sig = sig; /* Keep picky compilers happy */
545log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
546if (smtp_batched_input)
547 moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
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548smtp_notquit_exit(US"signal-exit", US"421",
549 US"%s: Service not available - closing connection", smtp_active_hostname);
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550exim_exit(EXIT_FAILURE);
551}
552
553
554
a14e5636 555
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556#ifdef EXPERIMENTAL_PROXY
557/*************************************************
a3bddaa8
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558* Restore socket timeout to previous value *
559*************************************************/
560/* If the previous value was successfully retrieved, restore
561it before returning control to the non-proxy routines
562
563Arguments: fd - File descriptor for input
564 get_ok - Successfully retrieved previous values
565 tvtmp - Time struct with previous values
566 vslen - Length of time struct
567Returns: none
568*/
569static void
570restore_socket_timeout(int fd, int get_ok, struct timeval tvtmp, socklen_t vslen)
571{
572if (get_ok == 0)
573 setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tvtmp, vslen);
574}
575
576/*************************************************
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577* Check if host is required proxy host *
578*************************************************/
579/* The function determines if inbound host will be a regular smtp host
580or if it is configured that it must use Proxy Protocol.
581
582Arguments: none
583Returns: bool
584*/
585
586static BOOL
587check_proxy_protocol_host()
588{
589int rc;
590/* Cannot configure local connection as a proxy inbound */
591if (sender_host_address == NULL) return proxy_session;
592
593rc = verify_check_this_host(&proxy_required_hosts, NULL, NULL,
594 sender_host_address, NULL);
595if (rc == OK)
596 {
597 DEBUG(D_receive)
598 debug_printf("Detected proxy protocol configured host\n");
599 proxy_session = TRUE;
600 }
601return proxy_session;
602}
603
604
605/*************************************************
a3c86431
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606* Setup host for proxy protocol *
607*************************************************/
608/* The function configures the connection based on a header from the
609inbound host to use Proxy Protocol. The specification is very exact
610so exit with an error if do not find the exact required pieces. This
611includes an incorrect number of spaces separating args.
612
613Arguments: none
614Returns: int
615*/
616
617static BOOL
618setup_proxy_protocol_host()
619{
620union {
621 struct {
622 uschar line[108];
623 } v1;
624 struct {
625 uschar sig[12];
626 uschar ver;
627 uschar cmd;
628 uschar fam;
629 uschar len;
630 union {
631 struct { /* TCP/UDP over IPv4, len = 12 */
632 uint32_t src_addr;
633 uint32_t dst_addr;
634 uint16_t src_port;
635 uint16_t dst_port;
636 } ip4;
637 struct { /* TCP/UDP over IPv6, len = 36 */
638 uint8_t src_addr[16];
639 uint8_t dst_addr[16];
640 uint16_t src_port;
641 uint16_t dst_port;
642 } ip6;
643 struct { /* AF_UNIX sockets, len = 216 */
644 uschar src_addr[108];
645 uschar dst_addr[108];
646 } unx;
647 } addr;
648 } v2;
649} hdr;
650
eb57651e
TL
651/* Temp variables used in PPv2 address:port parsing */
652uint16_t tmpport;
653char tmpip[INET_ADDRSTRLEN];
654struct sockaddr_in tmpaddr;
655char tmpip6[INET6_ADDRSTRLEN];
656struct sockaddr_in6 tmpaddr6;
657
658int get_ok = 0;
a3c86431 659int size, ret, fd;
a3c86431
TL
660const char v2sig[13] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A\x02";
661uschar *iptype; /* To display debug info */
662struct timeval tv;
a3bddaa8
TL
663socklen_t vslen = 0;
664struct timeval tvtmp;
665
666vslen = sizeof(struct timeval);
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TL
667
668fd = fileno(smtp_in);
669
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670/* Save current socket timeout values */
671get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tvtmp,
672 &vslen);
673
a3c86431
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674/* Proxy Protocol host must send header within a short time
675(default 3 seconds) or it's considered invalid */
676tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC;
677tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC;
678setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv,
679 sizeof(struct timeval));
a3bddaa8 680
a3c86431
TL
681do
682 {
eb57651e
TL
683 /* The inbound host was declared to be a Proxy Protocol host, so
684 don't do a PEEK into the data, actually slurp it up. */
685 ret = recv(fd, &hdr, sizeof(hdr), 0);
a3c86431
TL
686 }
687 while (ret == -1 && errno == EINTR);
688
689if (ret == -1)
a3bddaa8
TL
690 {
691 restore_socket_timeout(fd, get_ok, tvtmp, vslen);
a3c86431 692 return (errno == EAGAIN) ? 0 : ERRNO_PROXYFAIL;
a3bddaa8 693 }
a3c86431
TL
694
695if (ret >= 16 &&
696 memcmp(&hdr.v2, v2sig, 13) == 0)
697 {
698 DEBUG(D_receive) debug_printf("Detected PROXYv2 header\n");
699 size = 16 + hdr.v2.len;
700 if (ret < size)
701 {
702 DEBUG(D_receive) debug_printf("Truncated or too large PROXYv2 header\n");
703 goto proxyfail;
704 }
705 switch (hdr.v2.cmd)
706 {
707 case 0x01: /* PROXY command */
708 switch (hdr.v2.fam)
709 {
eb57651e
TL
710 case 0x11: /* TCPv4 address type */
711 iptype = US"IPv4";
712 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr;
713 inet_ntop(AF_INET, &(tmpaddr.sin_addr), (char *)&tmpip, sizeof(tmpip));
714 if (!string_is_ip_address(US tmpip,NULL))
715 {
716 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
a3c86431 717 return ERRNO_PROXYFAIL;
eb57651e
TL
718 }
719 proxy_host_address = sender_host_address;
720 sender_host_address = string_copy(US tmpip);
721 tmpport = ntohs(hdr.v2.addr.ip4.src_port);
722 proxy_host_port = sender_host_port;
723 sender_host_port = tmpport;
724 /* Save dest ip/port */
725 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr;
726 inet_ntop(AF_INET, &(tmpaddr.sin_addr), (char *)&tmpip, sizeof(tmpip));
727 if (!string_is_ip_address(US tmpip,NULL))
728 {
729 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
730 return ERRNO_PROXYFAIL;
731 }
732 proxy_target_address = string_copy(US tmpip);
733 tmpport = ntohs(hdr.v2.addr.ip4.dst_port);
734 proxy_target_port = tmpport;
a3c86431 735 goto done;
eb57651e
TL
736 case 0x21: /* TCPv6 address type */
737 iptype = US"IPv6";
738 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16);
739 inet_ntop(AF_INET6, &(tmpaddr6.sin6_addr), (char *)&tmpip6, sizeof(tmpip6));
740 if (!string_is_ip_address(US tmpip6,NULL))
741 {
742 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
743 return ERRNO_PROXYFAIL;
744 }
745 proxy_host_address = sender_host_address;
746 sender_host_address = string_copy(US tmpip6);
747 tmpport = ntohs(hdr.v2.addr.ip6.src_port);
748 proxy_host_port = sender_host_port;
749 sender_host_port = tmpport;
750 /* Save dest ip/port */
751 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16);
752 inet_ntop(AF_INET6, &(tmpaddr6.sin6_addr), (char *)&tmpip6, sizeof(tmpip6));
753 if (!string_is_ip_address(US tmpip6,NULL))
754 {
755 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
a3c86431 756 return ERRNO_PROXYFAIL;
eb57651e
TL
757 }
758 proxy_target_address = string_copy(US tmpip6);
759 tmpport = ntohs(hdr.v2.addr.ip6.dst_port);
760 proxy_target_port = tmpport;
a3c86431 761 goto done;
eb57651e
TL
762 default:
763 DEBUG(D_receive)
764 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
765 hdr.v2.fam);
766 goto proxyfail;
a3c86431
TL
767 }
768 /* Unsupported protocol, keep local connection address */
769 break;
770 case 0x00: /* LOCAL command */
771 /* Keep local connection address for LOCAL */
772 break;
773 default:
eb57651e
TL
774 DEBUG(D_receive)
775 debug_printf("Unsupported PROXYv2 command: 0x%02x\n",
776 hdr.v2.cmd);
a3c86431
TL
777 goto proxyfail;
778 }
779 }
780else if (ret >= 8 &&
781 memcmp(hdr.v1.line, "PROXY", 5) == 0)
782 {
783 uschar *p = string_copy(hdr.v1.line);
784 uschar *end = memchr(p, '\r', ret - 1);
785 uschar *sp; /* Utility variables follow */
786 int tmp_port;
787 char *endc;
788
789 if (!end || end[1] != '\n')
790 {
791 DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n");
792 goto proxyfail;
793 }
794 *end = '\0'; /* Terminate the string */
795 size = end + 2 - hdr.v1.line; /* Skip header + CRLF */
796 DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n");
797 /* Step through the string looking for the required fields. Ensure
798 strict adherance to required formatting, exit for any error. */
799 p += 5;
800 if (!isspace(*(p++)))
801 {
802 DEBUG(D_receive) debug_printf("Missing space after PROXY command\n");
803 goto proxyfail;
804 }
805 if (!Ustrncmp(p, CCS"TCP4", 4))
806 iptype = US"IPv4";
807 else if (!Ustrncmp(p,CCS"TCP6", 4))
808 iptype = US"IPv6";
809 else if (!Ustrncmp(p,CCS"UNKNOWN", 7))
810 {
811 iptype = US"Unknown";
812 goto done;
813 }
814 else
815 {
816 DEBUG(D_receive) debug_printf("Invalid TCP type\n");
817 goto proxyfail;
818 }
819
820 p += Ustrlen(iptype);
821 if (!isspace(*(p++)))
822 {
823 DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n");
824 goto proxyfail;
825 }
826 /* Find the end of the arg */
827 if ((sp = Ustrchr(p, ' ')) == NULL)
828 {
829 DEBUG(D_receive)
830 debug_printf("Did not find proxied src %s\n", iptype);
831 goto proxyfail;
832 }
833 *sp = '\0';
834 if(!string_is_ip_address(p,NULL))
835 {
836 DEBUG(D_receive)
837 debug_printf("Proxied src arg is not an %s address\n", iptype);
838 goto proxyfail;
839 }
a3bddaa8 840 proxy_host_address = sender_host_address;
a3c86431
TL
841 sender_host_address = p;
842 p = sp + 1;
843 if ((sp = Ustrchr(p, ' ')) == NULL)
844 {
845 DEBUG(D_receive)
846 debug_printf("Did not find proxy dest %s\n", iptype);
847 goto proxyfail;
848 }
849 *sp = '\0';
850 if(!string_is_ip_address(p,NULL))
851 {
852 DEBUG(D_receive)
853 debug_printf("Proxy dest arg is not an %s address\n", iptype);
854 goto proxyfail;
855 }
eb57651e 856 proxy_target_address = p;
a3c86431
TL
857 p = sp + 1;
858 if ((sp = Ustrchr(p, ' ')) == NULL)
859 {
860 DEBUG(D_receive) debug_printf("Did not find proxied src port\n");
861 goto proxyfail;
862 }
863 *sp = '\0';
864 tmp_port = strtol(CCS p,&endc,10);
865 if (*endc || tmp_port == 0)
866 {
867 DEBUG(D_receive)
868 debug_printf("Proxied src port '%s' not an integer\n", p);
869 goto proxyfail;
870 }
a3bddaa8 871 proxy_host_port = sender_host_port;
a3c86431
TL
872 sender_host_port = tmp_port;
873 p = sp + 1;
874 if ((sp = Ustrchr(p, '\0')) == NULL)
875 {
876 DEBUG(D_receive) debug_printf("Did not find proxy dest port\n");
877 goto proxyfail;
878 }
879 tmp_port = strtol(CCS p,&endc,10);
880 if (*endc || tmp_port == 0)
881 {
882 DEBUG(D_receive)
883 debug_printf("Proxy dest port '%s' not an integer\n", p);
884 goto proxyfail;
885 }
eb57651e 886 proxy_target_port = tmp_port;
a3c86431
TL
887 /* Already checked for /r /n above. Good V1 header received. */
888 goto done;
889 }
890else
891 {
892 /* Wrong protocol */
eb57651e 893 DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n");
a3c86431
TL
894 goto proxyfail;
895 }
896
897proxyfail:
a3bddaa8 898restore_socket_timeout(fd, get_ok, tvtmp, vslen);
a3c86431 899/* Don't flush any potential buffer contents. Any input should cause a
eb57651e 900 synchronization failure */
a3c86431
TL
901return FALSE;
902
903done:
a3bddaa8 904restore_socket_timeout(fd, get_ok, tvtmp, vslen);
a3c86431 905DEBUG(D_receive)
eb57651e 906 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype);
a3c86431
TL
907return proxy_session;
908}
909#endif
910
059ec3d9
PH
911/*************************************************
912* Read one command line *
913*************************************************/
914
915/* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
916There are sites that don't do this, and in any case internal SMTP probably
917should check only for LF. Consequently, we check here for LF only. The line
918ends up with [CR]LF removed from its end. If we get an overlong line, treat as
3ee512ff
PH
919an unknown command. The command is read into the global smtp_cmd_buffer so that
920it is available via $smtp_command.
059ec3d9
PH
921
922The character reading routine sets up a timeout for each block actually read
923from the input (which may contain more than one command). We set up a special
924signal handler that closes down the session on a timeout. Control does not
925return when it runs.
926
927Arguments:
928 check_sync if TRUE, check synchronization rules if global option is TRUE
929
930Returns: a code identifying the command (enumerated above)
931*/
932
933static int
934smtp_read_command(BOOL check_sync)
935{
936int c;
937int ptr = 0;
938smtp_cmd_list *p;
939BOOL hadnull = FALSE;
940
941os_non_restarting_signal(SIGALRM, command_timeout_handler);
942
943while ((c = (receive_getc)()) != '\n' && c != EOF)
944 {
3ee512ff 945 if (ptr >= smtp_cmd_buffer_size)
059ec3d9
PH
946 {
947 os_non_restarting_signal(SIGALRM, sigalrm_handler);
948 return OTHER_CMD;
949 }
950 if (c == 0)
951 {
952 hadnull = TRUE;
953 c = '?';
954 }
3ee512ff 955 smtp_cmd_buffer[ptr++] = c;
059ec3d9
PH
956 }
957
958receive_linecount++; /* For BSMTP errors */
959os_non_restarting_signal(SIGALRM, sigalrm_handler);
960
961/* If hit end of file, return pseudo EOF command. Whether we have a
962part-line already read doesn't matter, since this is an error state. */
963
964if (c == EOF) return EOF_CMD;
965
966/* Remove any CR and white space at the end of the line, and terminate the
967string. */
968
3ee512ff
PH
969while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
970smtp_cmd_buffer[ptr] = 0;
059ec3d9 971
3ee512ff 972DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
059ec3d9
PH
973
974/* NULLs are not allowed in SMTP commands */
975
976if (hadnull) return BADCHAR_CMD;
977
978/* Scan command list and return identity, having set the data pointer
979to the start of the actual data characters. Check for SMTP synchronization
980if required. */
981
982for (p = cmd_list; p < cmd_list_end; p++)
983 {
a3c86431
TL
984 #ifdef EXPERIMENTAL_PROXY
985 /* Only allow QUIT command if Proxy Protocol parsing failed */
986 if (proxy_session && proxy_session_failed)
987 {
988 if (p->cmd != QUIT_CMD)
989 continue;
990 }
991 #endif
084efe8d
PH
992 if (strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0 &&
993 (smtp_cmd_buffer[p->len-1] == ':' || /* "mail from:" or "rcpt to:" */
994 smtp_cmd_buffer[p->len] == 0 ||
995 smtp_cmd_buffer[p->len] == ' '))
059ec3d9
PH
996 {
997 if (smtp_inptr < smtp_inend && /* Outstanding input */
998 p->cmd < sync_cmd_limit && /* Command should sync */
999 check_sync && /* Local flag set */
1000 smtp_enforce_sync && /* Global flag set */
1001 sender_host_address != NULL && /* Not local input */
1002 !sender_host_notsocket) /* Really is a socket */
1003 return BADSYN_CMD;
1004
ca86f471
PH
1005 /* The variables $smtp_command and $smtp_command_argument point into the
1006 unmodified input buffer. A copy of the latter is taken for actual
1007 processing, so that it can be chopped up into separate parts if necessary,
1008 for example, when processing a MAIL command options such as SIZE that can
1009 follow the sender address. */
059ec3d9 1010
3ee512ff 1011 smtp_cmd_argument = smtp_cmd_buffer + p->len;
ca86f471
PH
1012 while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
1013 Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
1014 smtp_cmd_data = smtp_data_buffer;
059ec3d9
PH
1015
1016 /* Count non-mail commands from those hosts that are controlled in this
1017 way. The default is all hosts. We don't waste effort checking the list
1018 until we get a non-mail command, but then cache the result to save checking
1019 again. If there's a DEFER while checking the host, assume it's in the list.
1020
1021 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1022 start of each incoming message by fiddling with the value in the table. */
1023
1024 if (!p->is_mail_cmd)
1025 {
1026 if (count_nonmail == TRUE_UNSET) count_nonmail =
1027 verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL;
1028 if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail)
1029 return TOO_MANY_NONMAIL_CMD;
1030 }
1031
ca86f471
PH
1032 /* If there is data for a command that does not expect it, generate the
1033 error here. */
059ec3d9 1034
ca86f471 1035 return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
059ec3d9
PH
1036 }
1037 }
1038
a3c86431
TL
1039#ifdef EXPERIMENTAL_PROXY
1040/* Only allow QUIT command if Proxy Protocol parsing failed */
1041if (proxy_session && proxy_session_failed)
1042 return PROXY_FAIL_IGNORE_CMD;
1043#endif
1044
059ec3d9
PH
1045/* Enforce synchronization for unknown commands */
1046
1047if (smtp_inptr < smtp_inend && /* Outstanding input */
1048 check_sync && /* Local flag set */
1049 smtp_enforce_sync && /* Global flag set */
1050 sender_host_address != NULL && /* Not local input */
1051 !sender_host_notsocket) /* Really is a socket */
1052 return BADSYN_CMD;
1053
1054return OTHER_CMD;
1055}
1056
1057
1058
1059/*************************************************
a14e5636
PH
1060* Recheck synchronization *
1061*************************************************/
1062
1063/* Synchronization checks can never be perfect because a packet may be on its
1064way but not arrived when the check is done. Such checks can in any case only be
1065done when TLS is not in use. Normally, the checks happen when commands are
1066read: Exim ensures that there is no more input in the input buffer. In normal
1067cases, the response to the command will be fast, and there is no further check.
1068
1069However, for some commands an ACL is run, and that can include delays. In those
1070cases, it is useful to do another check on the input just before sending the
1071response. This also applies at the start of a connection. This function does
1072that check by means of the select() function, as long as the facility is not
1073disabled or inappropriate. A failure of select() is ignored.
1074
1075When there is unwanted input, we read it so that it appears in the log of the
1076error.
1077
1078Arguments: none
1079Returns: TRUE if all is well; FALSE if there is input pending
1080*/
1081
1082static BOOL
1083check_sync(void)
1084{
1085int fd, rc;
1086fd_set fds;
1087struct timeval tzero;
1088
1089if (!smtp_enforce_sync || sender_host_address == NULL ||
817d9f57 1090 sender_host_notsocket || tls_in.active >= 0)
a14e5636
PH
1091 return TRUE;
1092
1093fd = fileno(smtp_in);
1094FD_ZERO(&fds);
1095FD_SET(fd, &fds);
1096tzero.tv_sec = 0;
1097tzero.tv_usec = 0;
1098rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
1099
1100if (rc <= 0) return TRUE; /* Not ready to read */
1101rc = smtp_getc();
1102if (rc < 0) return TRUE; /* End of file or error */
1103
1104smtp_ungetc(rc);
1105rc = smtp_inend - smtp_inptr;
1106if (rc > 150) rc = 150;
1107smtp_inptr[rc] = 0;
1108return FALSE;
1109}
1110
1111
1112
1113/*************************************************
059ec3d9
PH
1114* Forced closedown of call *
1115*************************************************/
1116
1117/* This function is called from log.c when Exim is dying because of a serious
1118disaster, and also from some other places. If an incoming non-batched SMTP
1119channel is open, it swallows the rest of the incoming message if in the DATA
1120phase, sends the reply string, and gives an error to all subsequent commands
1121except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1122smtp_in.
1123
8f128379
PH
1124Arguments:
1125 message SMTP reply string to send, excluding the code
1126
059ec3d9
PH
1127Returns: nothing
1128*/
1129
1130void
1131smtp_closedown(uschar *message)
1132{
1133if (smtp_in == NULL || smtp_batched_input) return;
1134receive_swallow_smtp();
1135smtp_printf("421 %s\r\n", message);
1136
1137for (;;)
1138 {
1139 switch(smtp_read_command(FALSE))
1140 {
1141 case EOF_CMD:
1142 return;
1143
1144 case QUIT_CMD:
1145 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname);
1146 mac_smtp_fflush();
1147 return;
1148
1149 case RSET_CMD:
1150 smtp_printf("250 Reset OK\r\n");
1151 break;
1152
1153 default:
1154 smtp_printf("421 %s\r\n", message);
1155 break;
1156 }
1157 }
1158}
1159
1160
1161
1162
1163/*************************************************
1164* Set up connection info for logging *
1165*************************************************/
1166
1167/* This function is called when logging information about an SMTP connection.
1168It sets up appropriate source information, depending on the type of connection.
dac79d3e
PH
1169If sender_fullhost is NULL, we are at a very early stage of the connection;
1170just use the IP address.
059ec3d9
PH
1171
1172Argument: none
1173Returns: a string describing the connection
1174*/
1175
1176uschar *
1177smtp_get_connection_info(void)
1178{
dac79d3e
PH
1179uschar *hostname = (sender_fullhost == NULL)?
1180 sender_host_address : sender_fullhost;
1181
059ec3d9 1182if (host_checking)
dac79d3e 1183 return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1184
1185if (sender_host_unknown || sender_host_notsocket)
1186 return string_sprintf("SMTP connection from %s", sender_ident);
1187
1188if (is_inetd)
dac79d3e 1189 return string_sprintf("SMTP connection from %s (via inetd)", hostname);
059ec3d9
PH
1190
1191if ((log_extra_selector & LX_incoming_interface) != 0 &&
1192 interface_address != NULL)
dac79d3e 1193 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
059ec3d9
PH
1194 interface_address, interface_port);
1195
dac79d3e 1196return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1197}
1198
1199
1200
e45a1c37 1201#ifdef SUPPORT_TLS
887291d2
JH
1202/* Append TLS-related information to a log line
1203
1204Arguments:
1205 s String under construction: allocated string to extend, or NULL
1206 sizep Pointer to current allocation size (update on return), or NULL
1207 ptrp Pointer to index for new entries in string (update on return), or NULL
1208
1209Returns: Allocated string or NULL
1210*/
e45a1c37
JH
1211static uschar *
1212s_tlslog(uschar * s, int * sizep, int * ptrp)
1213{
1214 int size = sizep ? *sizep : 0;
1215 int ptr = ptrp ? *ptrp : 0;
1216
1217 if ((log_extra_selector & LX_tls_cipher) != 0 && tls_in.cipher != NULL)
1218 s = string_append(s, &size, &ptr, 2, US" X=", tls_in.cipher);
1219 if ((log_extra_selector & LX_tls_certificate_verified) != 0 &&
1220 tls_in.cipher != NULL)
1221 s = string_append(s, &size, &ptr, 2, US" CV=",
1222 tls_in.certificate_verified? "yes":"no");
1223 if ((log_extra_selector & LX_tls_peerdn) != 0 && tls_in.peerdn != NULL)
1224 s = string_append(s, &size, &ptr, 3, US" DN=\"",
1225 string_printing(tls_in.peerdn), US"\"");
1226 if ((log_extra_selector & LX_tls_sni) != 0 && tls_in.sni != NULL)
1227 s = string_append(s, &size, &ptr, 3, US" SNI=\"",
1228 string_printing(tls_in.sni), US"\"");
1229
67d81c10
JH
1230 if (s)
1231 {
1232 s[ptr] = '\0';
1233 if (sizep) *sizep = size;
1234 if (ptrp) *ptrp = ptr;
1235 }
e45a1c37
JH
1236 return s;
1237}
1238#endif
1239
059ec3d9 1240/*************************************************
b4ed4da0
PH
1241* Log lack of MAIL if so configured *
1242*************************************************/
1243
1244/* This function is called when an SMTP session ends. If the log selector
1245smtp_no_mail is set, write a log line giving some details of what has happened
1246in the SMTP session.
1247
1248Arguments: none
1249Returns: nothing
1250*/
1251
1252void
1253smtp_log_no_mail(void)
1254{
1255int size, ptr, i;
1256uschar *s, *sep;
1257
1258if (smtp_mailcmd_count > 0 || (log_extra_selector & LX_smtp_no_mail) == 0)
1259 return;
1260
1261s = NULL;
1262size = ptr = 0;
1263
1264if (sender_host_authenticated != NULL)
1265 {
1266 s = string_append(s, &size, &ptr, 2, US" A=", sender_host_authenticated);
1267 if (authenticated_id != NULL)
1268 s = string_append(s, &size, &ptr, 2, US":", authenticated_id);
1269 }
1270
1271#ifdef SUPPORT_TLS
e45a1c37 1272s = s_tlslog(s, &size, &ptr);
3f0945ff 1273#endif
b4ed4da0
PH
1274
1275sep = (smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE)?
1276 US" C=..." : US" C=";
1277for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
1278 {
1279 if (smtp_connection_had[i] != SCH_NONE)
1280 {
1281 s = string_append(s, &size, &ptr, 2, sep,
1282 smtp_names[smtp_connection_had[i]]);
1283 sep = US",";
1284 }
1285 }
1286
1287for (i = 0; i < smtp_ch_index; i++)
1288 {
1289 s = string_append(s, &size, &ptr, 2, sep, smtp_names[smtp_connection_had[i]]);
1290 sep = US",";
1291 }
1292
1293if (s != NULL) s[ptr] = 0; else s = US"";
1294log_write(0, LOG_MAIN, "no MAIL in SMTP connection from %s D=%s%s",
1295 host_and_ident(FALSE),
1296 readconf_printtime(time(NULL) - smtp_connection_start), s);
1297}
1298
1299
1300
1301/*************************************************
059ec3d9
PH
1302* Check HELO line and set sender_helo_name *
1303*************************************************/
1304
1305/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1306the domain name of the sending host, or an ip literal in square brackets. The
1307arrgument is placed in sender_helo_name, which is in malloc store, because it
1308must persist over multiple incoming messages. If helo_accept_junk is set, this
1309host is permitted to send any old junk (needed for some broken hosts).
1310Otherwise, helo_allow_chars can be used for rogue characters in general
1311(typically people want to let in underscores).
1312
1313Argument:
1314 s the data portion of the line (already past any white space)
1315
1316Returns: TRUE or FALSE
1317*/
1318
1319static BOOL
1320check_helo(uschar *s)
1321{
1322uschar *start = s;
1323uschar *end = s + Ustrlen(s);
1324BOOL yield = helo_accept_junk;
1325
1326/* Discard any previous helo name */
1327
1328if (sender_helo_name != NULL)
1329 {
1330 store_free(sender_helo_name);
1331 sender_helo_name = NULL;
1332 }
1333
1334/* Skip tests if junk is permitted. */
1335
1336if (!yield)
1337 {
1338 /* Allow the new standard form for IPv6 address literals, namely,
1339 [IPv6:....], and because someone is bound to use it, allow an equivalent
1340 IPv4 form. Allow plain addresses as well. */
1341
1342 if (*s == '[')
1343 {
1344 if (end[-1] == ']')
1345 {
1346 end[-1] = 0;
1347 if (strncmpic(s, US"[IPv6:", 6) == 0)
1348 yield = (string_is_ip_address(s+6, NULL) == 6);
1349 else if (strncmpic(s, US"[IPv4:", 6) == 0)
1350 yield = (string_is_ip_address(s+6, NULL) == 4);
1351 else
1352 yield = (string_is_ip_address(s+1, NULL) != 0);
1353 end[-1] = ']';
1354 }
1355 }
1356
1357 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1358 that have been configured (usually underscore - sigh). */
1359
1360 else if (*s != 0)
1361 {
1362 yield = TRUE;
1363 while (*s != 0)
1364 {
1365 if (!isalnum(*s) && *s != '.' && *s != '-' &&
1366 Ustrchr(helo_allow_chars, *s) == NULL)
1367 {
1368 yield = FALSE;
1369 break;
1370 }
1371 s++;
1372 }
1373 }
1374 }
1375
1376/* Save argument if OK */
1377
1378if (yield) sender_helo_name = string_copy_malloc(start);
1379return yield;
1380}
1381
1382
1383
1384
1385
1386/*************************************************
1387* Extract SMTP command option *
1388*************************************************/
1389
ca86f471 1390/* This function picks the next option setting off the end of smtp_cmd_data. It
059ec3d9
PH
1391is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1392things that can appear there.
1393
1394Arguments:
1395 name point this at the name
1396 value point this at the data string
1397
1398Returns: TRUE if found an option
1399*/
1400
1401static BOOL
1402extract_option(uschar **name, uschar **value)
1403{
1404uschar *n;
ca86f471 1405uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
059ec3d9
PH
1406while (isspace(*v)) v--;
1407v[1] = 0;
ca86f471 1408while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) v--;
059ec3d9
PH
1409
1410n = v;
fd98a5c6
JH
1411if (*v == '=')
1412{
1413 while(isalpha(n[-1])) n--;
1414 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
1415 if (!isspace(n[-1])) return FALSE;
1416 n[-1] = 0;
1417}
1418else
1419{
1420 n++;
1421 if (v == smtp_cmd_data) return FALSE;
1422}
059ec3d9 1423*v++ = 0;
fd98a5c6 1424*name = n;
059ec3d9
PH
1425*value = v;
1426return TRUE;
1427}
1428
1429
1430
1431
1432
059ec3d9
PH
1433/*************************************************
1434* Reset for new message *
1435*************************************************/
1436
1437/* This function is called whenever the SMTP session is reset from
1438within either of the setup functions.
1439
1440Argument: the stacking pool storage reset point
1441Returns: nothing
1442*/
1443
1444static void
1445smtp_reset(void *reset_point)
1446{
059ec3d9
PH
1447store_reset(reset_point);
1448recipients_list = NULL;
1449rcpt_count = rcpt_defer_count = rcpt_fail_count =
1450 raw_recipients_count = recipients_count = recipients_list_max = 0;
2e5b33cd 1451cancel_cutthrough_connection("smtp reset");
2e0c1448 1452message_linecount = 0;
059ec3d9 1453message_size = -1;
71fafd95 1454acl_added_headers = NULL;
e7568d51 1455acl_removed_headers = NULL;
059ec3d9 1456queue_only_policy = FALSE;
2679d413
PH
1457rcpt_smtp_response = NULL;
1458rcpt_smtp_response_same = TRUE;
1459rcpt_in_progress = FALSE;
69358f02 1460deliver_freeze = FALSE; /* Can be set by ACL */
6a3f1455 1461freeze_tell = freeze_tell_config; /* Can be set by ACL */
29aba418 1462fake_response = OK; /* Can be set by ACL */
6951ac6c 1463#ifdef WITH_CONTENT_SCAN
8523533c
TK
1464no_mbox_unspool = FALSE; /* Can be set by ACL */
1465#endif
69358f02 1466submission_mode = FALSE; /* Can be set by ACL */
f4ee74ac 1467suppress_local_fixups = suppress_local_fixups_default; /* Can be set by ACL */
69358f02
PH
1468active_local_from_check = local_from_check; /* Can be set by ACL */
1469active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
059ec3d9 1470sender_address = NULL;
2fe1a124 1471submission_name = NULL; /* Can be set by ACL */
059ec3d9
PH
1472raw_sender = NULL; /* After SMTP rewrite, before qualifying */
1473sender_address_unrewritten = NULL; /* Set only after verify rewrite */
1474sender_verified_list = NULL; /* No senders verified */
1475memset(sender_address_cache, 0, sizeof(sender_address_cache));
1476memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
1477authenticated_sender = NULL;
8523533c
TK
1478#ifdef EXPERIMENTAL_BRIGHTMAIL
1479bmi_run = 0;
1480bmi_verdicts = NULL;
1481#endif
80a47a2c 1482#ifndef DISABLE_DKIM
9e5d6b55 1483dkim_signers = NULL;
80a47a2c
TK
1484dkim_disable_verify = FALSE;
1485dkim_collect_input = FALSE;
f7572e5a 1486#endif
8523533c
TK
1487#ifdef EXPERIMENTAL_SPF
1488spf_header_comment = NULL;
1489spf_received = NULL;
8e669ac1 1490spf_result = NULL;
8523533c
TK
1491spf_smtp_comment = NULL;
1492#endif
059ec3d9
PH
1493body_linecount = body_zerocount = 0;
1494
870f6ba8
TF
1495sender_rate = sender_rate_limit = sender_rate_period = NULL;
1496ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
1497 /* Note that ratelimiters_conn persists across resets. */
1498
38a0a95f 1499/* Reset message ACL variables */
47ca6d6c 1500
38a0a95f 1501acl_var_m = NULL;
059ec3d9
PH
1502
1503/* The message body variables use malloc store. They may be set if this is
1504not the first message in an SMTP session and the previous message caused them
1505to be referenced in an ACL. */
1506
1507if (message_body != NULL)
1508 {
1509 store_free(message_body);
1510 message_body = NULL;
1511 }
1512
1513if (message_body_end != NULL)
1514 {
1515 store_free(message_body_end);
1516 message_body_end = NULL;
1517 }
1518
1519/* Warning log messages are also saved in malloc store. They are saved to avoid
1520repetition in the same message, but it seems right to repeat them for different
4e88a19f 1521messages. */
059ec3d9
PH
1522
1523while (acl_warn_logged != NULL)
1524 {
1525 string_item *this = acl_warn_logged;
1526 acl_warn_logged = acl_warn_logged->next;
1527 store_free(this);
1528 }
1529}
1530
1531
1532
1533
1534
1535/*************************************************
1536* Initialize for incoming batched SMTP message *
1537*************************************************/
1538
1539/* This function is called from smtp_setup_msg() in the case when
1540smtp_batched_input is true. This happens when -bS is used to pass a whole batch
1541of messages in one file with SMTP commands between them. All errors must be
1542reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
1543relevant. After an error on a sender, or an invalid recipient, the remainder
1544of the message is skipped. The value of received_protocol is already set.
1545
1546Argument: none
1547Returns: > 0 message successfully started (reached DATA)
1548 = 0 QUIT read or end of file reached
1549 < 0 should not occur
1550*/
1551
1552static int
1553smtp_setup_batch_msg(void)
1554{
1555int done = 0;
1556void *reset_point = store_get(0);
1557
1558/* Save the line count at the start of each transaction - single commands
1559like HELO and RSET count as whole transactions. */
1560
1561bsmtp_transaction_linecount = receive_linecount;
1562
1563if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
1564
1565smtp_reset(reset_point); /* Reset for start of message */
1566
1567/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
1568value. The values are 2 larger than the required yield of the function. */
1569
1570while (done <= 0)
1571 {
1572 uschar *errmess;
1573 uschar *recipient = NULL;
1574 int start, end, sender_domain, recipient_domain;
1575
1576 switch(smtp_read_command(FALSE))
1577 {
1578 /* The HELO/EHLO commands set sender_address_helo if they have
1579 valid data; otherwise they are ignored, except that they do
1580 a reset of the state. */
1581
1582 case HELO_CMD:
1583 case EHLO_CMD:
1584
ca86f471 1585 check_helo(smtp_cmd_data);
059ec3d9
PH
1586 /* Fall through */
1587
1588 case RSET_CMD:
1589 smtp_reset(reset_point);
1590 bsmtp_transaction_linecount = receive_linecount;
1591 break;
1592
1593
1594 /* The MAIL FROM command requires an address as an operand. All we
1595 do here is to parse it for syntactic correctness. The form "<>" is
1596 a special case which converts into an empty string. The start/end
1597 pointers in the original are not used further for this address, as
1598 it is the canonical extracted address which is all that is kept. */
1599
1600 case MAIL_CMD:
1601 if (sender_address != NULL)
1602 /* The function moan_smtp_batch() does not return. */
3ee512ff 1603 moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
059ec3d9 1604
ca86f471 1605 if (smtp_cmd_data[0] == 0)
059ec3d9 1606 /* The function moan_smtp_batch() does not return. */
3ee512ff 1607 moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
059ec3d9
PH
1608
1609 /* Reset to start of message */
1610
1611 smtp_reset(reset_point);
1612
1613 /* Apply SMTP rewrite */
1614
1615 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
1616 rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
1617 US"", global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
1618
1619 /* Extract the address; the TRUE flag allows <> as valid */
1620
1621 raw_sender =
1622 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
1623 TRUE);
1624
1625 if (raw_sender == NULL)
1626 /* The function moan_smtp_batch() does not return. */
3ee512ff 1627 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
1628
1629 sender_address = string_copy(raw_sender);
1630
1631 /* Qualify unqualified sender addresses if permitted to do so. */
1632
1633 if (sender_domain == 0 && sender_address[0] != 0 && sender_address[0] != '@')
1634 {
1635 if (allow_unqualified_sender)
1636 {
1637 sender_address = rewrite_address_qualify(sender_address, FALSE);
1638 DEBUG(D_receive) debug_printf("unqualified address %s accepted "
1639 "and rewritten\n", raw_sender);
1640 }
1641 /* The function moan_smtp_batch() does not return. */
3ee512ff 1642 else moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
059ec3d9
PH
1643 "a domain");
1644 }
1645 break;
1646
1647
1648 /* The RCPT TO command requires an address as an operand. All we do
1649 here is to parse it for syntactic correctness. There may be any number
1650 of RCPT TO commands, specifying multiple senders. We build them all into
1651 a data structure that is in argc/argv format. The start/end values
1652 given by parse_extract_address are not used, as we keep only the
1653 extracted address. */
1654
1655 case RCPT_CMD:
1656 if (sender_address == NULL)
1657 /* The function moan_smtp_batch() does not return. */
3ee512ff 1658 moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
059ec3d9 1659
ca86f471 1660 if (smtp_cmd_data[0] == 0)
059ec3d9 1661 /* The function moan_smtp_batch() does not return. */
3ee512ff 1662 moan_smtp_batch(smtp_cmd_buffer, "501 RCPT TO must have an address operand");
059ec3d9
PH
1663
1664 /* Check maximum number allowed */
1665
1666 if (recipients_max > 0 && recipients_count + 1 > recipients_max)
1667 /* The function moan_smtp_batch() does not return. */
3ee512ff 1668 moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
059ec3d9
PH
1669 recipients_max_reject? "552": "452");
1670
1671 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
1672 recipient address */
1673
1674 recipient = ((rewrite_existflags & rewrite_smtp) != 0)?
ca86f471
PH
1675 rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
1676 global_rewrite_rules) : smtp_cmd_data;
059ec3d9
PH
1677
1678 /* rfc821_domains = TRUE; << no longer needed */
1679 recipient = parse_extract_address(recipient, &errmess, &start, &end,
1680 &recipient_domain, FALSE);
1681 /* rfc821_domains = FALSE; << no longer needed */
1682
1683 if (recipient == NULL)
1684 /* The function moan_smtp_batch() does not return. */
3ee512ff 1685 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9
PH
1686
1687 /* If the recipient address is unqualified, qualify it if permitted. Then
1688 add it to the list of recipients. */
1689
1690 if (recipient_domain == 0)
1691 {
1692 if (allow_unqualified_recipient)
1693 {
1694 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
1695 recipient);
1696 recipient = rewrite_address_qualify(recipient, TRUE);
1697 }
1698 /* The function moan_smtp_batch() does not return. */
3ee512ff 1699 else moan_smtp_batch(smtp_cmd_buffer, "501 recipient address must contain "
059ec3d9
PH
1700 "a domain");
1701 }
1702 receive_add_recipient(recipient, -1);
1703 break;
1704
1705
1706 /* The DATA command is legal only if it follows successful MAIL FROM
1707 and RCPT TO commands. This function is complete when a valid DATA
1708 command is encountered. */
1709
1710 case DATA_CMD:
1711 if (sender_address == NULL || recipients_count <= 0)
1712 {
1713 /* The function moan_smtp_batch() does not return. */
1714 if (sender_address == NULL)
3ee512ff 1715 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
1716 "503 MAIL FROM:<sender> command must precede DATA");
1717 else
3ee512ff 1718 moan_smtp_batch(smtp_cmd_buffer,
059ec3d9
PH
1719 "503 RCPT TO:<recipient> must precede DATA");
1720 }
1721 else
1722 {
1723 done = 3; /* DATA successfully achieved */
1724 message_ended = END_NOTENDED; /* Indicate in middle of message */
1725 }
1726 break;
1727
1728
1729 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
1730
1731 case VRFY_CMD:
1732 case EXPN_CMD:
1733 case HELP_CMD:
1734 case NOOP_CMD:
1735 case ETRN_CMD:
1736 bsmtp_transaction_linecount = receive_linecount;
1737 break;
1738
1739
1740 case EOF_CMD:
1741 case QUIT_CMD:
1742 done = 2;
1743 break;
1744
1745
1746 case BADARG_CMD:
1747 /* The function moan_smtp_batch() does not return. */
3ee512ff 1748 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
059ec3d9
PH
1749 break;
1750
1751
1752 case BADCHAR_CMD:
1753 /* The function moan_smtp_batch() does not return. */
3ee512ff 1754 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
059ec3d9
PH
1755 break;
1756
1757
1758 default:
1759 /* The function moan_smtp_batch() does not return. */
3ee512ff 1760 moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
059ec3d9
PH
1761 break;
1762 }
1763 }
1764
1765return done - 2; /* Convert yield values */
1766}
1767
1768
1769
1770
1771/*************************************************
1772* Start an SMTP session *
1773*************************************************/
1774
1775/* This function is called at the start of an SMTP session. Thereafter,
1776smtp_setup_msg() is called to initiate each separate message. This
1777function does host-specific testing, and outputs the banner line.
1778
1779Arguments: none
1780Returns: FALSE if the session can not continue; something has
1781 gone wrong, or the connection to the host is blocked
1782*/
1783
1784BOOL
1785smtp_start_session(void)
1786{
1787int size = 256;
4e88a19f
PH
1788int ptr, esclen;
1789uschar *user_msg, *log_msg;
1790uschar *code, *esc;
059ec3d9
PH
1791uschar *p, *s, *ss;
1792
b4ed4da0
PH
1793smtp_connection_start = time(NULL);
1794for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
1795 smtp_connection_had[smtp_ch_index] = SCH_NONE;
1796smtp_ch_index = 0;
1797
00f00ca5
PH
1798/* Default values for certain variables */
1799
059ec3d9 1800helo_seen = esmtp = helo_accept_junk = FALSE;
b4ed4da0 1801smtp_mailcmd_count = 0;
059ec3d9
PH
1802count_nonmail = TRUE_UNSET;
1803synprot_error_count = unknown_command_count = nonmail_command_count = 0;
1804smtp_delay_mail = smtp_rlm_base;
1805auth_advertised = FALSE;
1806pipelining_advertised = FALSE;
cf8b11a5 1807pipelining_enable = TRUE;
059ec3d9 1808sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
8f128379 1809smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
059ec3d9
PH
1810
1811memset(sender_host_cache, 0, sizeof(sender_host_cache));
1812
33d73e3b
PH
1813/* If receiving by -bs from a trusted user, or testing with -bh, we allow
1814authentication settings from -oMaa to remain in force. */
1815
1816if (!host_checking && !sender_host_notsocket) sender_host_authenticated = NULL;
059ec3d9
PH
1817authenticated_by = NULL;
1818
1819#ifdef SUPPORT_TLS
817d9f57 1820tls_in.cipher = tls_in.peerdn = NULL;
059ec3d9
PH
1821tls_advertised = FALSE;
1822#endif
1823
1824/* Reset ACL connection variables */
1825
38a0a95f 1826acl_var_c = NULL;
059ec3d9 1827
ca86f471 1828/* Allow for trailing 0 in the command and data buffers. */
3ee512ff 1829
ca86f471 1830smtp_cmd_buffer = (uschar *)malloc(2*smtp_cmd_buffer_size + 2);
3ee512ff 1831if (smtp_cmd_buffer == NULL)
059ec3d9
PH
1832 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
1833 "malloc() failed for SMTP command buffer");
2416c261 1834smtp_cmd_buffer[0] = 0;
ca86f471 1835smtp_data_buffer = smtp_cmd_buffer + smtp_cmd_buffer_size + 1;
059ec3d9
PH
1836
1837/* For batched input, the protocol setting can be overridden from the
1838command line by a trusted caller. */
1839
1840if (smtp_batched_input)
1841 {
1842 if (received_protocol == NULL) received_protocol = US"local-bsmtp";
1843 }
1844
1845/* For non-batched SMTP input, the protocol setting is forced here. It will be
1846reset later if any of EHLO/AUTH/STARTTLS are received. */
1847
1848else
1849 received_protocol =
1850 protocols[pnormal] + ((sender_host_address != NULL)? pnlocal : 0);
1851
1852/* Set up the buffer for inputting using direct read() calls, and arrange to
1853call the local functions instead of the standard C ones. */
1854
1855smtp_inbuffer = (uschar *)malloc(in_buffer_size);
1856if (smtp_inbuffer == NULL)
1857 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
1858receive_getc = smtp_getc;
1859receive_ungetc = smtp_ungetc;
1860receive_feof = smtp_feof;
1861receive_ferror = smtp_ferror;
58eb016e 1862receive_smtp_buffered = smtp_buffered;
059ec3d9
PH
1863smtp_inptr = smtp_inend = smtp_inbuffer;
1864smtp_had_eof = smtp_had_error = 0;
1865
1866/* Set up the message size limit; this may be host-specific */
1867
d45b1de8
PH
1868thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
1869if (expand_string_message != NULL)
059ec3d9
PH
1870 {
1871 if (thismessage_size_limit == -1)
1872 log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
1873 "%s", expand_string_message);
1874 else
1875 log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: "
1876 "%s", expand_string_message);
1877 smtp_closedown(US"Temporary local problem - please try later");
1878 return FALSE;
1879 }
1880
1881/* When a message is input locally via the -bs or -bS options, sender_host_
1882unknown is set unless -oMa was used to force an IP address, in which case it
1883is checked like a real remote connection. When -bs is used from inetd, this
1884flag is not set, causing the sending host to be checked. The code that deals
1885with IP source routing (if configured) is never required for -bs or -bS and
1886the flag sender_host_notsocket is used to suppress it.
1887
1888If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
1889reserve for certain hosts and/or networks. */
1890
1891if (!sender_host_unknown)
1892 {
1893 int rc;
1894 BOOL reserved_host = FALSE;
1895
1896 /* Look up IP options (source routing info) on the socket if this is not an
1897 -oMa "host", and if any are found, log them and drop the connection.
1898
1899 Linux (and others now, see below) is different to everyone else, so there
1900 has to be some conditional compilation here. Versions of Linux before 2.1.15
1901 used a structure whose name was "options". Somebody finally realized that
1902 this name was silly, and it got changed to "ip_options". I use the
1903 newer name here, but there is a fudge in the script that sets up os.h
1904 to define a macro in older Linux systems.
1905
1906 Sigh. Linux is a fast-moving target. Another generation of Linux uses
1907 glibc 2, which has chosen ip_opts for the structure name. This is now
1908 really a glibc thing rather than a Linux thing, so the condition name
1909 has been changed to reflect this. It is relevant also to GNU/Hurd.
1910
1911 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
1912 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
1913 a special macro defined in the os.h file.
1914
1915 Some DGUX versions on older hardware appear not to support IP options at
1916 all, so there is now a general macro which can be set to cut out this
1917 support altogether.
1918
1919 How to do this properly in IPv6 is not yet known. */
1920
1921 #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
1922
1923 #ifdef GLIBC_IP_OPTIONS
1924 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
1925 #define OPTSTYLE 1
1926 #else
1927 #define OPTSTYLE 2
1928 #endif
1929 #elif defined DARWIN_IP_OPTIONS
1930 #define OPTSTYLE 2
1931 #else
1932 #define OPTSTYLE 3
1933 #endif
1934
1935 if (!host_checking && !sender_host_notsocket)
1936 {
1937 #if OPTSTYLE == 1
36a3b041 1938 EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
059ec3d9
PH
1939 struct ip_options *ipopt = store_get(optlen);
1940 #elif OPTSTYLE == 2
1941 struct ip_opts ipoptblock;
1942 struct ip_opts *ipopt = &ipoptblock;
36a3b041 1943 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
1944 #else
1945 struct ipoption ipoptblock;
1946 struct ipoption *ipopt = &ipoptblock;
36a3b041 1947 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
1948 #endif
1949
1950 /* Occasional genuine failures of getsockopt() have been seen - for
1951 example, "reset by peer". Therefore, just log and give up on this
1952 call, unless the error is ENOPROTOOPT. This error is given by systems
1953 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
1954 of writing. So for that error, carry on - we just can't do an IP options
1955 check. */
1956
1957 DEBUG(D_receive) debug_printf("checking for IP options\n");
1958
1959 if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, (uschar *)(ipopt),
1960 &optlen) < 0)
1961 {
1962 if (errno != ENOPROTOOPT)
1963 {
1964 log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
1965 host_and_ident(FALSE), strerror(errno));
1966 smtp_printf("451 SMTP service not available\r\n");
1967 return FALSE;
1968 }
1969 }
1970
1971 /* Deal with any IP options that are set. On the systems I have looked at,
1972 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
1973 more logging data than will fit in big_buffer. Nevertheless, after somebody
1974 questioned this code, I've added in some paranoid checking. */
1975
1976 else if (optlen > 0)
1977 {
1978 uschar *p = big_buffer;
1979 uschar *pend = big_buffer + big_buffer_size;
1980 uschar *opt, *adptr;
1981 int optcount;
1982 struct in_addr addr;
1983
1984 #if OPTSTYLE == 1
1985 uschar *optstart = (uschar *)(ipopt->__data);
1986 #elif OPTSTYLE == 2
1987 uschar *optstart = (uschar *)(ipopt->ip_opts);
1988 #else
1989 uschar *optstart = (uschar *)(ipopt->ipopt_list);
1990 #endif
1991
1992 DEBUG(D_receive) debug_printf("IP options exist\n");
1993
1994 Ustrcpy(p, "IP options on incoming call:");
1995 p += Ustrlen(p);
1996
1997 for (opt = optstart; opt != NULL &&
1998 opt < (uschar *)(ipopt) + optlen;)
1999 {
2000 switch (*opt)
2001 {
2002 case IPOPT_EOL:
2003 opt = NULL;
2004 break;
2005
2006 case IPOPT_NOP:
2007 opt++;
2008 break;
2009
2010 case IPOPT_SSRR:
2011 case IPOPT_LSRR:
2012 if (!string_format(p, pend-p, " %s [@%s",
2013 (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
2014 #if OPTSTYLE == 1
2015 inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
2016 #elif OPTSTYLE == 2
2017 inet_ntoa(ipopt->ip_dst)))
2018 #else
2019 inet_ntoa(ipopt->ipopt_dst)))
2020 #endif
2021 {
2022 opt = NULL;
2023 break;
2024 }
2025
2026 p += Ustrlen(p);
2027 optcount = (opt[1] - 3) / sizeof(struct in_addr);
2028 adptr = opt + 3;
2029 while (optcount-- > 0)
2030 {
2031 memcpy(&addr, adptr, sizeof(addr));
2032 if (!string_format(p, pend - p - 1, "%s%s",
2033 (optcount == 0)? ":" : "@", inet_ntoa(addr)))
2034 {
2035 opt = NULL;
2036 break;
2037 }
2038 p += Ustrlen(p);
2039 adptr += sizeof(struct in_addr);
2040 }
2041 *p++ = ']';
2042 opt += opt[1];
2043 break;
2044
2045 default:
2046 {
2047 int i;
2048 if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
2049 Ustrcat(p, "[ ");
2050 p += 2;
2051 for (i = 0; i < opt[1]; i++)
2052 {
2053 sprintf(CS p, "%2.2x ", opt[i]);
2054 p += 3;
2055 }
2056 *p++ = ']';
2057 }
2058 opt += opt[1];
2059 break;
2060 }
2061 }
2062
2063 *p = 0;
2064 log_write(0, LOG_MAIN, "%s", big_buffer);
2065
2066 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2067
2068 log_write(0, LOG_MAIN|LOG_REJECT,
2069 "connection from %s refused (IP options)", host_and_ident(FALSE));
2070
2071 smtp_printf("554 SMTP service not available\r\n");
2072 return FALSE;
2073 }
2074
2075 /* Length of options = 0 => there are no options */
2076
2077 else DEBUG(D_receive) debug_printf("no IP options found\n");
2078 }
2079 #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
2080
2081 /* Set keep-alive in socket options. The option is on by default. This
2082 setting is an attempt to get rid of some hanging connections that stick in
2083 read() when the remote end (usually a dialup) goes away. */
2084
2085 if (smtp_accept_keepalive && !sender_host_notsocket)
2086 ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
2087
2088 /* If the current host matches host_lookup, set the name by doing a
2089 reverse lookup. On failure, sender_host_name will be NULL and
2090 host_lookup_failed will be TRUE. This may or may not be serious - optional
2091 checks later. */
2092
2093 if (verify_check_host(&host_lookup) == OK)
2094 {
2095 (void)host_name_lookup();
2096 host_build_sender_fullhost();
2097 }
2098
2099 /* Delay this until we have the full name, if it is looked up. */
2100
2101 set_process_info("handling incoming connection from %s",
2102 host_and_ident(FALSE));
2103
2104 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2105 smtps port for use with older style SSL MTAs. */
2106
2107 #ifdef SUPPORT_TLS
817d9f57 2108 if (tls_in.on_connect && tls_server_start(tls_require_ciphers) != OK)
059ec3d9
PH
2109 return FALSE;
2110 #endif
2111
2112 /* Test for explicit connection rejection */
2113
2114 if (verify_check_host(&host_reject_connection) == OK)
2115 {
2116 log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
2117 "from %s (host_reject_connection)", host_and_ident(FALSE));
2118 smtp_printf("554 SMTP service not available\r\n");
2119 return FALSE;
2120 }
2121
afb3eaaf
PH
2122 /* Test with TCP Wrappers if so configured. There is a problem in that
2123 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2124 such as disks dying. In these cases, it is desirable to reject with a 4xx
2125 error instead of a 5xx error. There isn't a "right" way to detect such
2126 problems. The following kludge is used: errno is zeroed before calling
2127 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2128 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2129 not exist). */
059ec3d9
PH
2130
2131 #ifdef USE_TCP_WRAPPERS
afb3eaaf 2132 errno = 0;
5dc43717
JJ
2133 tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name);
2134 if (tcp_wrappers_name == NULL)
2135 {
2136 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
2137 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
2138 expand_string_message);
2139 }
2140 if (!hosts_ctl(tcp_wrappers_name,
059ec3d9
PH
2141 (sender_host_name == NULL)? STRING_UNKNOWN : CS sender_host_name,
2142 (sender_host_address == NULL)? STRING_UNKNOWN : CS sender_host_address,
2143 (sender_ident == NULL)? STRING_UNKNOWN : CS sender_ident))
2144 {
afb3eaaf
PH
2145 if (errno == 0 || errno == ENOENT)
2146 {
2147 HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
2148 log_write(L_connection_reject,
2149 LOG_MAIN|LOG_REJECT, "refused connection from %s "
2150 "(tcp wrappers)", host_and_ident(FALSE));
2151 smtp_printf("554 SMTP service not available\r\n");
2152 }
2153 else
2154 {
2155 int save_errno = errno;
2156 HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
2157 "errno value %d\n", save_errno);
2158 log_write(L_connection_reject,
2159 LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
2160 "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
2161 smtp_printf("451 Temporary local problem - please try later\r\n");
2162 }
059ec3d9
PH
2163 return FALSE;
2164 }
2165 #endif
2166
b01dd148
PH
2167 /* Check for reserved slots. The value of smtp_accept_count has already been
2168 incremented to include this process. */
059ec3d9
PH
2169
2170 if (smtp_accept_max > 0 &&
b01dd148 2171 smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
059ec3d9
PH
2172 {
2173 if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
2174 {
2175 log_write(L_connection_reject,
2176 LOG_MAIN, "temporarily refused connection from %s: not in "
2177 "reserve list: connected=%d max=%d reserve=%d%s",
b01dd148 2178 host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
059ec3d9
PH
2179 smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
2180 smtp_printf("421 %s: Too many concurrent SMTP connections; "
2181 "please try again later\r\n", smtp_active_hostname);
2182 return FALSE;
2183 }
2184 reserved_host = TRUE;
2185 }
2186
2187 /* If a load level above which only messages from reserved hosts are
2188 accepted is set, check the load. For incoming calls via the daemon, the
2189 check is done in the superior process if there are no reserved hosts, to
2190 save a fork. In all cases, the load average will already be available
2191 in a global variable at this point. */
2192
2193 if (smtp_load_reserve >= 0 &&
2194 load_average > smtp_load_reserve &&
2195 !reserved_host &&
2196 verify_check_host(&smtp_reserve_hosts) != OK)
2197 {
2198 log_write(L_connection_reject,
2199 LOG_MAIN, "temporarily refused connection from %s: not in "
2200 "reserve list and load average = %.2f", host_and_ident(FALSE),
2201 (double)load_average/1000.0);
2202 smtp_printf("421 %s: Too much load; please try again later\r\n",
2203 smtp_active_hostname);
2204 return FALSE;
2205 }
2206
2207 /* Determine whether unqualified senders or recipients are permitted
2208 for this host. Unfortunately, we have to do this every time, in order to
2209 set the flags so that they can be inspected when considering qualifying
2210 addresses in the headers. For a site that permits no qualification, this
2211 won't take long, however. */
2212
2213 allow_unqualified_sender =
2214 verify_check_host(&sender_unqualified_hosts) == OK;
2215
2216 allow_unqualified_recipient =
2217 verify_check_host(&recipient_unqualified_hosts) == OK;
2218
2219 /* Determine whether HELO/EHLO is required for this host. The requirement
2220 can be hard or soft. */
2221
2222 helo_required = verify_check_host(&helo_verify_hosts) == OK;
2223 if (!helo_required)
2224 helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
2225
2226 /* Determine whether this hosts is permitted to send syntactic junk
2227 after a HELO or EHLO command. */
2228
2229 helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
2230 }
2231
2232/* For batch SMTP input we are now done. */
2233
2234if (smtp_batched_input) return TRUE;
2235
a3c86431
TL
2236#ifdef EXPERIMENTAL_PROXY
2237/* If valid Proxy Protocol source is connecting, set up session.
2238 * Failure will not allow any SMTP function other than QUIT. */
2239proxy_session = FALSE;
2240proxy_session_failed = FALSE;
2241if (check_proxy_protocol_host())
2242 {
2243 if (setup_proxy_protocol_host() == FALSE)
2244 {
2245 proxy_session_failed = TRUE;
2246 DEBUG(D_receive)
2247 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
2248 }
2249 else
2250 {
2251 sender_host_name = NULL;
2252 (void)host_name_lookup();
2253 host_build_sender_fullhost();
2254 }
2255 }
2256#endif
2257
059ec3d9
PH
2258/* Run the ACL if it exists */
2259
4e88a19f 2260user_msg = NULL;
059ec3d9
PH
2261if (acl_smtp_connect != NULL)
2262 {
2263 int rc;
64ffc24f 2264 rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
059ec3d9
PH
2265 &log_msg);
2266 if (rc != OK)
2267 {
2268 (void)smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
2269 return FALSE;
2270 }
2271 }
2272
2273/* Output the initial message for a two-way SMTP connection. It may contain
2274newlines, which then cause a multi-line response to be given. */
2275
4e88a19f
PH
2276code = US"220"; /* Default status code */
2277esc = US""; /* Default extended status code */
2278esclen = 0; /* Length of esc */
2279
2280if (user_msg == NULL)
2281 {
2282 s = expand_string(smtp_banner);
2283 if (s == NULL)
2284 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
2285 "failed: %s", smtp_banner, expand_string_message);
2286 }
2287else
2288 {
2289 int codelen = 3;
2290 s = user_msg;
2291 smtp_message_code(&code, &codelen, &s, NULL);
d6a96edc 2292 if (codelen > 4)
4e88a19f
PH
2293 {
2294 esc = code + 4;
2295 esclen = codelen - 4;
2296 }
2297 }
059ec3d9
PH
2298
2299/* Remove any terminating newlines; might as well remove trailing space too */
2300
2301p = s + Ustrlen(s);
2302while (p > s && isspace(p[-1])) p--;
2303*p = 0;
2304
2305/* It seems that CC:Mail is braindead, and assumes that the greeting message
2306is all contained in a single IP packet. The original code wrote out the
2307greeting using several calls to fprint/fputc, and on busy servers this could
2308cause it to be split over more than one packet - which caused CC:Mail to fall
2309over when it got the second part of the greeting after sending its first
2310command. Sigh. To try to avoid this, build the complete greeting message
2311first, and output it in one fell swoop. This gives a better chance of it
2312ending up as a single packet. */
2313
2314ss = store_get(size);
2315ptr = 0;
2316
2317p = s;
2318do /* At least once, in case we have an empty string */
2319 {
2320 int len;
2321 uschar *linebreak = Ustrchr(p, '\n');
4e88a19f 2322 ss = string_cat(ss, &size, &ptr, code, 3);
059ec3d9
PH
2323 if (linebreak == NULL)
2324 {
2325 len = Ustrlen(p);
4e88a19f 2326 ss = string_cat(ss, &size, &ptr, US" ", 1);
059ec3d9
PH
2327 }
2328 else
2329 {
2330 len = linebreak - p;
4e88a19f 2331 ss = string_cat(ss, &size, &ptr, US"-", 1);
059ec3d9 2332 }
4e88a19f 2333 ss = string_cat(ss, &size, &ptr, esc, esclen);
059ec3d9
PH
2334 ss = string_cat(ss, &size, &ptr, p, len);
2335 ss = string_cat(ss, &size, &ptr, US"\r\n", 2);
2336 p += len;
2337 if (linebreak != NULL) p++;
2338 }
2339while (*p != 0);
2340
2341ss[ptr] = 0; /* string_cat leaves room for this */
2342
2343/* Before we write the banner, check that there is no input pending, unless
2344this synchronisation check is disabled. */
2345
a14e5636 2346if (!check_sync())
059ec3d9 2347 {
a14e5636
PH
2348 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
2349 "synchronization error (input sent without waiting for greeting): "
2350 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
2351 string_printing(smtp_inptr));
2352 smtp_printf("554 SMTP synchronization error\r\n");
2353 return FALSE;
059ec3d9
PH
2354 }
2355
2356/* Now output the banner */
2357
2358smtp_printf("%s", ss);
2359return TRUE;
2360}
2361
2362
2363
2364
2365
2366/*************************************************
2367* Handle SMTP syntax and protocol errors *
2368*************************************************/
2369
2370/* Write to the log for SMTP syntax errors in incoming commands, if configured
2371to do so. Then transmit the error response. The return value depends on the
2372number of syntax and protocol errors in this SMTP session.
2373
2374Arguments:
2375 type error type, given as a log flag bit
2376 code response code; <= 0 means don't send a response
2377 data data to reflect in the response (can be NULL)
2378 errmess the error message
2379
2380Returns: -1 limit of syntax/protocol errors NOT exceeded
2381 +1 limit of syntax/protocol errors IS exceeded
2382
2383These values fit in with the values of the "done" variable in the main
2384processing loop in smtp_setup_msg(). */
2385
2386static int
2387synprot_error(int type, int code, uschar *data, uschar *errmess)
2388{
2389int yield = -1;
2390
2391log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
2392 (type == L_smtp_syntax_error)? "syntax" : "protocol",
3ee512ff 2393 string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
059ec3d9
PH
2394
2395if (++synprot_error_count > smtp_max_synprot_errors)
2396 {
2397 yield = 1;
2398 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
2399 "syntax or protocol errors (last command was \"%s\")",
3ee512ff 2400 host_and_ident(FALSE), smtp_cmd_buffer);
059ec3d9
PH
2401 }
2402
2403if (code > 0)
2404 {
2405 smtp_printf("%d%c%s%s%s\r\n", code, (yield == 1)? '-' : ' ',
2406 (data == NULL)? US"" : data, (data == NULL)? US"" : US": ", errmess);
2407 if (yield == 1)
2408 smtp_printf("%d Too many syntax or protocol errors\r\n", code);
2409 }
2410
2411return yield;
2412}
2413
2414
2415
2416
2417/*************************************************
2418* Log incomplete transactions *
2419*************************************************/
2420
2421/* This function is called after a transaction has been aborted by RSET, QUIT,
2422connection drops or other errors. It logs the envelope information received
2423so far in order to preserve address verification attempts.
2424
2425Argument: string to indicate what aborted the transaction
2426Returns: nothing
2427*/
2428
2429static void
2430incomplete_transaction_log(uschar *what)
2431{
2432if (sender_address == NULL || /* No transaction in progress */
2433 (log_write_selector & L_smtp_incomplete_transaction) == 0 /* Not logging */
2434 ) return;
2435
2436/* Build list of recipients for logging */
2437
2438if (recipients_count > 0)
2439 {
2440 int i;
2441 raw_recipients = store_get(recipients_count * sizeof(uschar *));
2442 for (i = 0; i < recipients_count; i++)
2443 raw_recipients[i] = recipients_list[i].address;
2444 raw_recipients_count = recipients_count;
2445 }
2446
2447log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
2448 "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
2449}
2450
2451
2452
2453
2454/*************************************************
2455* Send SMTP response, possibly multiline *
2456*************************************************/
2457
2458/* There are, it seems, broken clients out there that cannot handle multiline
2459responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
2460output nothing for non-final calls, and only the first line for anything else.
2461
2462Arguments:
a5bd321b 2463 code SMTP code, may involve extended status codes
d6a96edc 2464 codelen length of smtp code; if > 4 there's an ESC
059ec3d9
PH
2465 final FALSE if the last line isn't the final line
2466 msg message text, possibly containing newlines
2467
2468Returns: nothing
2469*/
2470
2471void
a5bd321b 2472smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
059ec3d9 2473{
a5bd321b
PH
2474int esclen = 0;
2475uschar *esc = US"";
2476
059ec3d9
PH
2477if (!final && no_multiline_responses) return;
2478
d6a96edc 2479if (codelen > 4)
a5bd321b
PH
2480 {
2481 esc = code + 4;
2482 esclen = codelen - 4;
2483 }
2484
2679d413
PH
2485/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
2486have had the same. Note: this code is also present in smtp_printf(). It would
2487be tidier to have it only in one place, but when it was added, it was easier to
2488do it that way, so as not to have to mess with the code for the RCPT command,
2489which sometimes uses smtp_printf() and sometimes smtp_respond(). */
2490
2491if (rcpt_in_progress)
2492 {
2493 if (rcpt_smtp_response == NULL)
2494 rcpt_smtp_response = string_copy(msg);
2495 else if (rcpt_smtp_response_same &&
2496 Ustrcmp(rcpt_smtp_response, msg) != 0)
2497 rcpt_smtp_response_same = FALSE;
2498 rcpt_in_progress = FALSE;
2499 }
2500
2501/* Not output the message, splitting it up into multiple lines if necessary. */
2502
059ec3d9
PH
2503for (;;)
2504 {
2505 uschar *nl = Ustrchr(msg, '\n');
2506 if (nl == NULL)
2507 {
a5bd321b 2508 smtp_printf("%.3s%c%.*s%s\r\n", code, final? ' ':'-', esclen, esc, msg);
059ec3d9
PH
2509 return;
2510 }
2511 else if (nl[1] == 0 || no_multiline_responses)
2512 {
a5bd321b
PH
2513 smtp_printf("%.3s%c%.*s%.*s\r\n", code, final? ' ':'-', esclen, esc,
2514 (int)(nl - msg), msg);
059ec3d9
PH
2515 return;
2516 }
2517 else
2518 {
a5bd321b 2519 smtp_printf("%.3s-%.*s%.*s\r\n", code, esclen, esc, (int)(nl - msg), msg);
059ec3d9
PH
2520 msg = nl + 1;
2521 while (isspace(*msg)) msg++;
2522 }
2523 }
2524}
2525
2526
2527
2528
2529/*************************************************
4e88a19f
PH
2530* Parse user SMTP message *
2531*************************************************/
2532
2533/* This function allows for user messages overriding the response code details
2534by providing a suitable response code string at the start of the message
2535user_msg. Check the message for starting with a response code and optionally an
2536extended status code. If found, check that the first digit is valid, and if so,
2537change the code pointer and length to use the replacement. An invalid code
2538causes a panic log; in this case, if the log messages is the same as the user
2539message, we must also adjust the value of the log message to show the code that
2540is actually going to be used (the original one).
2541
2542This function is global because it is called from receive.c as well as within
2543this module.
2544
d6a96edc
PH
2545Note that the code length returned includes the terminating whitespace
2546character, which is always included in the regex match.
2547
4e88a19f
PH
2548Arguments:
2549 code SMTP code, may involve extended status codes
d6a96edc 2550 codelen length of smtp code; if > 4 there's an ESC
4e88a19f
PH
2551 msg message text
2552 log_msg optional log message, to be adjusted with the new SMTP code
2553
2554Returns: nothing
2555*/
2556
2557void
2558smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg)
2559{
2560int n;
2561int ovector[3];
2562
2563if (msg == NULL || *msg == NULL) return;
2564
2565n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
2566 PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int));
2567if (n < 0) return;
2568
2569if ((*msg)[0] != (*code)[0])
2570 {
2571 log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
2572 "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
2573 if (log_msg != NULL && *log_msg == *msg)
2574 *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
2575 }
2576else
2577 {
2578 *code = *msg;
2579 *codelen = ovector[1]; /* Includes final space */
2580 }
2581*msg += ovector[1]; /* Chop the code off the message */
2582return;
2583}
2584
2585
2586
2587
2588/*************************************************
059ec3d9
PH
2589* Handle an ACL failure *
2590*************************************************/
2591
2592/* This function is called when acl_check() fails. As well as calls from within
2593this module, it is called from receive.c for an ACL after DATA. It sorts out
2594logging the incident, and sets up the error response. A message containing
2595newlines is turned into a multiline SMTP response, but for logging, only the
2596first line is used.
2597
a5bd321b
PH
2598There's a table of default permanent failure response codes to use in
2599globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
2600defaults disabled in Exim. However, discussion in connection with RFC 821bis
2601(aka RFC 2821) has concluded that the response should be 252 in the disabled
2602state, because there are broken clients that try VRFY before RCPT. A 5xx
2603response should be given only when the address is positively known to be
2604undeliverable. Sigh. Also, for ETRN, 458 is given on refusal, and for AUTH,
2605503.
2606
2607From Exim 4.63, it is possible to override the response code details by
2608providing a suitable response code string at the start of the message provided
2609in user_msg. The code's first digit is checked for validity.
059ec3d9
PH
2610
2611Arguments:
2612 where where the ACL was called from
2613 rc the failure code
2614 user_msg a message that can be included in an SMTP response
2615 log_msg a message for logging
2616
2617Returns: 0 in most cases
2618 2 if the failure code was FAIL_DROP, in which case the
2619 SMTP connection should be dropped (this value fits with the
2620 "done" variable in smtp_setup_msg() below)
2621*/
2622
2623int
2624smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
2625{
059ec3d9 2626BOOL drop = rc == FAIL_DROP;
a5bd321b 2627int codelen = 3;
a5bd321b 2628uschar *smtp_code;
059ec3d9
PH
2629uschar *lognl;
2630uschar *sender_info = US"";
64ffc24f 2631uschar *what =
8523533c 2632#ifdef WITH_CONTENT_SCAN
64ffc24f 2633 (where == ACL_WHERE_MIME)? US"during MIME ACL checks" :
8e669ac1 2634#endif
64ffc24f
PH
2635 (where == ACL_WHERE_PREDATA)? US"DATA" :
2636 (where == ACL_WHERE_DATA)? US"after DATA" :
fd98a5c6
JH
2637#ifdef EXPERIMENTAL_PRDR
2638 (where == ACL_WHERE_PRDR)? US"after DATA PRDR" :
2639#endif
ca86f471 2640 (smtp_cmd_data == NULL)?
64ffc24f 2641 string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]) :
ca86f471 2642 string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data);
059ec3d9
PH
2643
2644if (drop) rc = FAIL;
2645
4e88a19f 2646/* Set the default SMTP code, and allow a user message to change it. */
a5bd321b
PH
2647
2648smtp_code = (rc != FAIL)? US"451" : acl_wherecodes[where];
4e88a19f 2649smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg);
a5bd321b 2650
059ec3d9
PH
2651/* We used to have sender_address here; however, there was a bug that was not
2652updating sender_address after a rewrite during a verify. When this bug was
2653fixed, sender_address at this point became the rewritten address. I'm not sure
2654this is what should be logged, so I've changed to logging the unrewritten
2655address to retain backward compatibility. */
2656
8523533c 2657#ifndef WITH_CONTENT_SCAN
059ec3d9 2658if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
8523533c
TK
2659#else
2660if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
2661#endif
059ec3d9 2662 {
b98bb9ac
PP
2663 sender_info = string_sprintf("F=<%s>%s%s%s%s ",
2664 sender_address_unrewritten ? sender_address_unrewritten : sender_address,
2665 sender_host_authenticated ? US" A=" : US"",
2666 sender_host_authenticated ? sender_host_authenticated : US"",
2667 sender_host_authenticated && authenticated_id ? US":" : US"",
2668 sender_host_authenticated && authenticated_id ? authenticated_id : US""
2669 );
059ec3d9
PH
2670 }
2671
2672/* If there's been a sender verification failure with a specific message, and
2673we have not sent a response about it yet, do so now, as a preliminary line for
278c6e6c
PH
2674failures, but not defers. However, always log it for defer, and log it for fail
2675unless the sender_verify_fail log selector has been turned off. */
059ec3d9
PH
2676
2677if (sender_verified_failed != NULL &&
2678 !testflag(sender_verified_failed, af_sverify_told))
2679 {
2679d413
PH
2680 BOOL save_rcpt_in_progress = rcpt_in_progress;
2681 rcpt_in_progress = FALSE; /* So as not to treat these as the error */
2682
059ec3d9
PH
2683 setflag(sender_verified_failed, af_sverify_told);
2684
278c6e6c
PH
2685 if (rc != FAIL || (log_extra_selector & LX_sender_verify_fail) != 0)
2686 log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
2687 host_and_ident(TRUE),
2688 ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
2689 sender_verified_failed->address,
2690 (sender_verified_failed->message == NULL)? US"" :
2691 string_sprintf(": %s", sender_verified_failed->message));
059ec3d9
PH
2692
2693 if (rc == FAIL && sender_verified_failed->user_message != NULL)
a5bd321b 2694 smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
059ec3d9
PH
2695 testflag(sender_verified_failed, af_verify_pmfail)?
2696 "Postmaster verification failed while checking <%s>\n%s\n"
2697 "Several RFCs state that you are required to have a postmaster\n"
2698 "mailbox for each mail domain. This host does not accept mail\n"
2699 "from domains whose servers reject the postmaster address."
2700 :
2701 testflag(sender_verified_failed, af_verify_nsfail)?
2702 "Callback setup failed while verifying <%s>\n%s\n"
2703 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
2704 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
2705 "RFC requirements, and stops you from receiving standard bounce\n"
2706 "messages. This host does not accept mail from domains whose servers\n"
2707 "refuse bounces."
2708 :
2709 "Verification failed for <%s>\n%s",
2710 sender_verified_failed->address,
2711 sender_verified_failed->user_message));
2679d413
PH
2712
2713 rcpt_in_progress = save_rcpt_in_progress;
059ec3d9
PH
2714 }
2715
2716/* Sort out text for logging */
2717
2718log_msg = (log_msg == NULL)? US"" : string_sprintf(": %s", log_msg);
2719lognl = Ustrchr(log_msg, '\n');
2720if (lognl != NULL) *lognl = 0;
2721
2722/* Send permanent failure response to the command, but the code used isn't
2723always a 5xx one - see comments at the start of this function. If the original
2724rc was FAIL_DROP we drop the connection and yield 2. */
2725
a5bd321b 2726if (rc == FAIL) smtp_respond(smtp_code, codelen, TRUE, (user_msg == NULL)?
059ec3d9
PH
2727 US"Administrative prohibition" : user_msg);
2728
2729/* Send temporary failure response to the command. Don't give any details,
2730unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
2731verb, and for a header verify when smtp_return_error_details is set.
2732
2733This conditional logic is all somewhat of a mess because of the odd
2734interactions between temp_details and return_error_details. One day it should
2735be re-implemented in a tidier fashion. */
2736
2737else
2738 {
2739 if (acl_temp_details && user_msg != NULL)
2740 {
2741 if (smtp_return_error_details &&
2742 sender_verified_failed != NULL &&
2743 sender_verified_failed->message != NULL)
2744 {
a5bd321b 2745 smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
059ec3d9 2746 }
a5bd321b 2747 smtp_respond(smtp_code, codelen, TRUE, user_msg);
059ec3d9
PH
2748 }
2749 else
a5bd321b
PH
2750 smtp_respond(smtp_code, codelen, TRUE,
2751 US"Temporary local problem - please try later");
059ec3d9
PH
2752 }
2753
6ea85e9a
PH
2754/* Log the incident to the logs that are specified by log_reject_target
2755(default main, reject). This can be empty to suppress logging of rejections. If
2756the connection is not forcibly to be dropped, return 0. Otherwise, log why it
2757is closing if required and return 2. */
059ec3d9 2758
6ea85e9a 2759if (log_reject_target != 0)
887291d2 2760 {
e45a1c37 2761#ifdef SUPPORT_TLS
887291d2
JH
2762 uschar * s = s_tlslog(NULL, NULL, NULL);
2763 if (!s) s = US"";
e45a1c37 2764#else
887291d2 2765 uschar * s = US"";
e45a1c37 2766#endif
887291d2
JH
2767 log_write(0, log_reject_target, "%s%s %s%srejected %s%s",
2768 host_and_ident(TRUE), s,
6ea85e9a 2769 sender_info, (rc == FAIL)? US"" : US"temporarily ", what, log_msg);
887291d2 2770 }
059ec3d9
PH
2771
2772if (!drop) return 0;
2773
2774log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
2775 smtp_get_connection_info());
8f128379
PH
2776
2777/* Run the not-quit ACL, but without any custom messages. This should not be a
2778problem, because we get here only if some other ACL has issued "drop", and
2779in that case, *its* custom messages will have been used above. */
2780
2781smtp_notquit_exit(US"acl-drop", NULL, NULL);
059ec3d9
PH
2782return 2;
2783}
2784
2785
2786
2787
2788/*************************************************
8f128379
PH
2789* Handle SMTP exit when QUIT is not given *
2790*************************************************/
2791
2792/* This function provides a logging/statistics hook for when an SMTP connection
2793is dropped on the floor or the other end goes away. It's a global function
2794because it's called from receive.c as well as this module. As well as running
2795the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
2796response, either with a custom message from the ACL, or using a default. There
2797is one case, however, when no message is output - after "drop". In that case,
2798the ACL that obeyed "drop" has already supplied the custom message, and NULL is
2799passed to this function.
2800
2801In case things go wrong while processing this function, causing an error that
2802may re-enter this funtion, there is a recursion check.
2803
2804Arguments:
2805 reason What $smtp_notquit_reason will be set to in the ACL;
2806 if NULL, the ACL is not run
2807 code The error code to return as part of the response
2808 defaultrespond The default message if there's no user_msg
2809
2810Returns: Nothing
2811*/
2812
2813void
2814smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
2815{
2816int rc;
2817uschar *user_msg = NULL;
2818uschar *log_msg = NULL;
2819
2820/* Check for recursive acll */
2821
2822if (smtp_exit_function_called)
2823 {
2824 log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
2825 reason);
2826 return;
2827 }
2828smtp_exit_function_called = TRUE;
2829
2830/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
2831
2832if (acl_smtp_notquit != NULL && reason != NULL)
2833 {
2834 smtp_notquit_reason = reason;
2835 rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
2836 &log_msg);
2837 if (rc == ERROR)
2838 log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
2839 log_msg);
2840 }
2841
2842/* Write an SMTP response if we are expected to give one. As the default
2843responses are all internal, they should always fit in the buffer, but code a
2844warning, just in case. Note that string_vformat() still leaves a complete
2845string, even if it is incomplete. */
2846
2847if (code != NULL && defaultrespond != NULL)
2848 {
2849 if (user_msg == NULL)
2850 {
2851 uschar buffer[128];
2852 va_list ap;
2853 va_start(ap, defaultrespond);
2854 if (!string_vformat(buffer, sizeof(buffer), CS defaultrespond, ap))
2855 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_notquit_exit()");
2856 smtp_printf("%s %s\r\n", code, buffer);
2857 va_end(ap);
2858 }
2859 else
2860 smtp_respond(code, 3, TRUE, user_msg);
2861 mac_smtp_fflush();
2862 }
2863}
2864
2865
2866
2867
2868/*************************************************
d7b47fd0
PH
2869* Verify HELO argument *
2870*************************************************/
2871
2872/* This function is called if helo_verify_hosts or helo_try_verify_hosts is
2873matched. It is also called from ACL processing if verify = helo is used and
2874verification was not previously tried (i.e. helo_try_verify_hosts was not
2875matched). The result of its processing is to set helo_verified and
2876helo_verify_failed. These variables should both be FALSE for this function to
2877be called.
2878
2879Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow
2880for IPv6 ::ffff: literals.
2881
2882Argument: none
2883Returns: TRUE if testing was completed;
2884 FALSE on a temporary failure
2885*/
2886
2887BOOL
2888smtp_verify_helo(void)
2889{
2890BOOL yield = TRUE;
2891
2892HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n",
2893 sender_helo_name);
2894
2895if (sender_helo_name == NULL)
2896 {
2897 HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n");
2898 }
2899
d1d5595c
PH
2900/* Deal with the case of -bs without an IP address */
2901
2902else if (sender_host_address == NULL)
2903 {
2904 HDEBUG(D_receive) debug_printf("no client IP address: assume success\n");
2905 helo_verified = TRUE;
2906 }
2907
2908/* Deal with the more common case when there is a sending IP address */
2909
d7b47fd0
PH
2910else if (sender_helo_name[0] == '[')
2911 {
2912 helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address,
2913 Ustrlen(sender_host_address)) == 0;
2914
2915 #if HAVE_IPV6
2916 if (!helo_verified)
2917 {
2918 if (strncmpic(sender_host_address, US"::ffff:", 7) == 0)
2919 helo_verified = Ustrncmp(sender_helo_name + 1,
2920 sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0;
2921 }
2922 #endif
2923
2924 HDEBUG(D_receive)
2925 { if (helo_verified) debug_printf("matched host address\n"); }
2926 }
2927
2928/* Do a reverse lookup if one hasn't already given a positive or negative
2929response. If that fails, or the name doesn't match, try checking with a forward
2930lookup. */
2931
2932else
2933 {
2934 if (sender_host_name == NULL && !host_lookup_failed)
2935 yield = host_name_lookup() != DEFER;
2936
2937 /* If a host name is known, check it and all its aliases. */
2938
2939 if (sender_host_name != NULL)
2940 {
2941 helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0;
2942
2943 if (helo_verified)
2944 {
2945 HDEBUG(D_receive) debug_printf("matched host name\n");
2946 }
2947 else
2948 {
2949 uschar **aliases = sender_host_aliases;
2950 while (*aliases != NULL)
2951 {
2952 helo_verified = strcmpic(*aliases++, sender_helo_name) == 0;
2953 if (helo_verified) break;
2954 }
2955 HDEBUG(D_receive)
2956 {
2957 if (helo_verified)
2958 debug_printf("matched alias %s\n", *(--aliases));
2959 }
2960 }
2961 }
2962
2963 /* Final attempt: try a forward lookup of the helo name */
2964
2965 if (!helo_verified)
2966 {
2967 int rc;
2968 host_item h;
2969 h.name = sender_helo_name;
2970 h.address = NULL;
2971 h.mx = MX_NONE;
2972 h.next = NULL;
2973 HDEBUG(D_receive) debug_printf("getting IP address for %s\n",
2974 sender_helo_name);
322050c2 2975 rc = host_find_byname(&h, NULL, 0, NULL, TRUE);
d7b47fd0
PH
2976 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
2977 {
2978 host_item *hh = &h;
2979 while (hh != NULL)
2980 {
2981 if (Ustrcmp(hh->address, sender_host_address) == 0)
2982 {
2983 helo_verified = TRUE;
2984 HDEBUG(D_receive)
2985 debug_printf("IP address for %s matches calling address\n",
2986 sender_helo_name);
2987 break;
2988 }
2989 hh = hh->next;
2990 }
2991 }
2992 }
2993 }
2994
d1d5595c 2995if (!helo_verified) helo_verify_failed = TRUE; /* We've tried ... */
d7b47fd0
PH
2996return yield;
2997}
2998
2999
3000
3001
3002/*************************************************
4e88a19f
PH
3003* Send user response message *
3004*************************************************/
3005
3006/* This function is passed a default response code and a user message. It calls
3007smtp_message_code() to check and possibly modify the response code, and then
3008calls smtp_respond() to transmit the response. I put this into a function
3009just to avoid a lot of repetition.
3010
3011Arguments:
3012 code the response code
3013 user_msg the user message
3014
3015Returns: nothing
3016*/
3017
3018static void
3019smtp_user_msg(uschar *code, uschar *user_msg)
3020{
3021int len = 3;
3022smtp_message_code(&code, &len, &user_msg, NULL);
3023smtp_respond(code, len, TRUE, user_msg);
3024}
3025
3026
3027
4e88a19f 3028/*************************************************
059ec3d9
PH
3029* Initialize for SMTP incoming message *
3030*************************************************/
3031
3032/* This function conducts the initial dialogue at the start of an incoming SMTP
3033message, and builds a list of recipients. However, if the incoming message
3034is part of a batch (-bS option) a separate function is called since it would
3035be messy having tests splattered about all over this function. This function
3036therefore handles the case where interaction is occurring. The input and output
3037files are set up in smtp_in and smtp_out.
3038
3039The global recipients_list is set to point to a vector of recipient_item
3040blocks, whose number is given by recipients_count. This is extended by the
3041receive_add_recipient() function. The global variable sender_address is set to
3042the sender's address. The yield is +1 if a message has been successfully
3043started, 0 if a QUIT command was encountered or the connection was refused from
3044the particular host, or -1 if the connection was lost.
3045
3046Argument: none
3047
3048Returns: > 0 message successfully started (reached DATA)
3049 = 0 QUIT read or end of file reached or call refused
3050 < 0 lost connection
3051*/
3052
3053int
3054smtp_setup_msg(void)
3055{
3056int done = 0;
3057BOOL toomany = FALSE;
3058BOOL discarded = FALSE;
3059BOOL last_was_rej_mail = FALSE;
3060BOOL last_was_rcpt = FALSE;
3061void *reset_point = store_get(0);
3062
3063DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n");
3064
3065/* Reset for start of new message. We allow one RSET not to be counted as a
3066nonmail command, for those MTAs that insist on sending it between every
3067message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of
3068TLS between messages (an Exim client may do this if it has messages queued up
3069for the host). Note: we do NOT reset AUTH at this point. */
3070
3071smtp_reset(reset_point);
3072message_ended = END_NOTSTARTED;
3073
3074cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE;
3075cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE;
3076cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
3077#ifdef SUPPORT_TLS
3078cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE;
3079#endif
3080
3081/* Set the local signal handler for SIGTERM - it tries to end off tidily */
3082
3083os_non_restarting_signal(SIGTERM, command_sigterm_handler);
3084
3085/* Batched SMTP is handled in a different function. */
3086
3087if (smtp_batched_input) return smtp_setup_batch_msg();
3088
3089/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
3090value. The values are 2 larger than the required yield of the function. */
3091
3092while (done <= 0)
3093 {
3094 uschar **argv;
3095 uschar *etrn_command;
3096 uschar *etrn_serialize_key;
3097 uschar *errmess;
4e88a19f
PH
3098 uschar *log_msg, *smtp_code;
3099 uschar *user_msg = NULL;
059ec3d9
PH
3100 uschar *recipient = NULL;
3101 uschar *hello = NULL;
3102 uschar *set_id = NULL;
3103 uschar *s, *ss;
3104 BOOL was_rej_mail = FALSE;
3105 BOOL was_rcpt = FALSE;
3106 void (*oldsignal)(int);
3107 pid_t pid;
3108 int start, end, sender_domain, recipient_domain;
3109 int ptr, size, rc;
f78eb7c6 3110 int c, i;
059ec3d9
PH
3111 auth_instance *au;
3112
3113 switch(smtp_read_command(TRUE))
3114 {
3115 /* The AUTH command is not permitted to occur inside a transaction, and may
c46782ef
PH
3116 occur successfully only once per connection. Actually, that isn't quite
3117 true. When TLS is started, all previous information about a connection must
3118 be discarded, so a new AUTH is permitted at that time.
3119
3120 AUTH may only be used when it has been advertised. However, it seems that
3121 there are clients that send AUTH when it hasn't been advertised, some of
3122 them even doing this after HELO. And there are MTAs that accept this. Sigh.
3123 So there's a get-out that allows this to happen.
059ec3d9
PH
3124
3125 AUTH is initially labelled as a "nonmail command" so that one occurrence
3126 doesn't get counted. We change the label here so that multiple failing
3127 AUTHS will eventually hit the nonmail threshold. */
3128
3129 case AUTH_CMD:
b4ed4da0 3130 HAD(SCH_AUTH);
059ec3d9
PH
3131 authentication_failed = TRUE;
3132 cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE;
3133
c46782ef 3134 if (!auth_advertised && !allow_auth_unadvertised)
059ec3d9
PH
3135 {
3136 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3137 US"AUTH command used when not advertised");
3138 break;
3139 }
3140 if (sender_host_authenticated != NULL)
3141 {
3142 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3143 US"already authenticated");
3144 break;
3145 }
3146 if (sender_address != NULL)
3147 {
3148 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3149 US"not permitted in mail transaction");
3150 break;
3151 }
3152
3153 /* Check the ACL */
3154
3155 if (acl_smtp_auth != NULL)
3156 {
64ffc24f 3157 rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, &user_msg, &log_msg);
059ec3d9
PH
3158 if (rc != OK)
3159 {
3160 done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
3161 break;
3162 }
3163 }
3164
3165 /* Find the name of the requested authentication mechanism. */
3166
ca86f471
PH
3167 s = smtp_cmd_data;
3168 while ((c = *smtp_cmd_data) != 0 && !isspace(c))
059ec3d9
PH
3169 {
3170 if (!isalnum(c) && c != '-' && c != '_')
3171 {
3172 done = synprot_error(L_smtp_syntax_error, 501, NULL,
3173 US"invalid character in authentication mechanism name");
3174 goto COMMAND_LOOP;
3175 }
ca86f471 3176 smtp_cmd_data++;
059ec3d9
PH
3177 }
3178
3179 /* If not at the end of the line, we must be at white space. Terminate the
3180 name and move the pointer on to any data that may be present. */
3181
ca86f471 3182 if (*smtp_cmd_data != 0)
059ec3d9 3183 {
ca86f471
PH
3184 *smtp_cmd_data++ = 0;
3185 while (isspace(*smtp_cmd_data)) smtp_cmd_data++;
059ec3d9
PH
3186 }
3187
3188 /* Search for an authentication mechanism which is configured for use
c46782ef
PH
3189 as a server and which has been advertised (unless, sigh, allow_auth_
3190 unadvertised is set). */
059ec3d9
PH
3191
3192 for (au = auths; au != NULL; au = au->next)
3193 {
3194 if (strcmpic(s, au->public_name) == 0 && au->server &&
c46782ef 3195 (au->advertised || allow_auth_unadvertised)) break;
059ec3d9
PH
3196 }
3197
3198 if (au == NULL)
3199 {
3200 done = synprot_error(L_smtp_protocol_error, 504, NULL,
3201 string_sprintf("%s authentication mechanism not supported", s));
3202 break;
3203 }
3204
f78eb7c6
PH
3205 /* Run the checking code, passing the remainder of the command line as
3206 data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
3207 it as the only set numerical variable. The authenticator may set $auth<n>
3208 and also set other numeric variables. The $auth<n> variables are preferred
3209 nowadays; the numerical variables remain for backwards compatibility.
059ec3d9 3210
f78eb7c6
PH
3211 Afterwards, have a go at expanding the set_id string, even if
3212 authentication failed - for bad passwords it can be useful to log the
3213 userid. On success, require set_id to expand and exist, and put it in
3214 authenticated_id. Save this in permanent store, as the working store gets
3215 reset at HELO, RSET, etc. */
3216
3217 for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
059ec3d9
PH
3218 expand_nmax = 0;
3219 expand_nlength[0] = 0; /* $0 contains nothing */
3220
ca86f471 3221 c = (au->info->servercode)(au, smtp_cmd_data);
059ec3d9
PH
3222 if (au->set_id != NULL) set_id = expand_string(au->set_id);
3223 expand_nmax = -1; /* Reset numeric variables */
f78eb7c6 3224 for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
059ec3d9 3225
0612b098
PH
3226 /* The value of authenticated_id is stored in the spool file and printed in
3227 log lines. It must not contain binary zeros or newline characters. In
3228 normal use, it never will, but when playing around or testing, this error
3229 can (did) happen. To guard against this, ensure that the id contains only
3230 printing characters. */
3231
3232 if (set_id != NULL) set_id = string_printing(set_id);
3233
059ec3d9
PH
3234 /* For the non-OK cases, set up additional logging data if set_id
3235 is not empty. */
3236
3237 if (c != OK)
3238 {
3239 if (set_id != NULL && *set_id != 0)
3240 set_id = string_sprintf(" (set_id=%s)", set_id);
3241 else set_id = US"";
3242 }
3243
3244 /* Switch on the result */
3245
3246 switch(c)
3247 {
3248 case OK:
3249 if (au->set_id == NULL || set_id != NULL) /* Complete success */
3250 {
3251 if (set_id != NULL) authenticated_id = string_copy_malloc(set_id);
3252 sender_host_authenticated = au->name;
3253 authentication_failed = FALSE;
2d07a215 3254 authenticated_fail_id = NULL; /* Impossible to already be set? */
059ec3d9 3255 received_protocol =
817d9f57 3256 protocols[pextend + pauthed + ((tls_in.active >= 0)? pcrpted:0)] +
059ec3d9
PH
3257 ((sender_host_address != NULL)? pnlocal : 0);
3258 s = ss = US"235 Authentication succeeded";
3259 authenticated_by = au;
3260 break;
3261 }
3262
3263 /* Authentication succeeded, but we failed to expand the set_id string.
3264 Treat this as a temporary error. */
3265
3266 auth_defer_msg = expand_string_message;
3267 /* Fall through */
3268
3269 case DEFER:
2d07a215 3270 if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
059ec3d9
PH
3271 s = string_sprintf("435 Unable to authenticate at present%s",
3272 auth_defer_user_msg);
3273 ss = string_sprintf("435 Unable to authenticate at present%s: %s",
3274 set_id, auth_defer_msg);
3275 break;
3276
3277 case BAD64:
3278 s = ss = US"501 Invalid base64 data";
3279 break;
3280
3281 case CANCELLED:
3282 s = ss = US"501 Authentication cancelled";
3283 break;
3284
3285 case UNEXPECTED:
3286 s = ss = US"553 Initial data not expected";
3287 break;
3288
3289 case FAIL:
2d07a215 3290 if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
059ec3d9
PH
3291 s = US"535 Incorrect authentication data";
3292 ss = string_sprintf("535 Incorrect authentication data%s", set_id);
3293 break;
3294
3295 default:
2d07a215 3296 if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
059ec3d9
PH
3297 s = US"435 Internal error";
3298 ss = string_sprintf("435 Internal error%s: return %d from authentication "
3299 "check", set_id, c);
3300 break;
3301 }
3302
3303 smtp_printf("%s\r\n", s);
3304 if (c != OK)
3305 log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
3306 au->name, host_and_ident(FALSE), ss);
3307
3308 break; /* AUTH_CMD */
3309
3310 /* The HELO/EHLO commands are permitted to appear in the middle of a
3311 session as well as at the beginning. They have the effect of a reset in
3312 addition to their other functions. Their absence at the start cannot be
3313 taken to be an error.
3314
3315 RFC 2821 says:
3316
3317 If the EHLO command is not acceptable to the SMTP server, 501, 500,
3318 or 502 failure replies MUST be returned as appropriate. The SMTP
3319 server MUST stay in the same state after transmitting these replies
3320 that it was in before the EHLO was received.
3321
3322 Therefore, we do not do the reset until after checking the command for
3323 acceptability. This change was made for Exim release 4.11. Previously
3324 it did the reset first. */
3325
3326 case HELO_CMD:
b4ed4da0 3327 HAD(SCH_HELO);
059ec3d9
PH
3328 hello = US"HELO";
3329 esmtp = FALSE;
3330 goto HELO_EHLO;
3331
3332 case EHLO_CMD:
b4ed4da0 3333 HAD(SCH_EHLO);
059ec3d9
PH
3334 hello = US"EHLO";
3335 esmtp = TRUE;
3336
3337 HELO_EHLO: /* Common code for HELO and EHLO */
3338 cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE;
3339 cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE;
3340
3341 /* Reject the HELO if its argument was invalid or non-existent. A
3342 successful check causes the argument to be saved in malloc store. */
3343
ca86f471 3344 if (!check_helo(smtp_cmd_data))
059ec3d9
PH
3345 {
3346 smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello);
3347
3348 log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically "
3349 "invalid argument(s): %s", hello, host_and_ident(FALSE),
3ee512ff
PH
3350 (*smtp_cmd_argument == 0)? US"(no argument given)" :
3351 string_printing(smtp_cmd_argument));
059ec3d9
PH
3352
3353 if (++synprot_error_count > smtp_max_synprot_errors)
3354 {
3355 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
3356 "syntax or protocol errors (last command was \"%s\")",
3ee512ff 3357 host_and_ident(FALSE), smtp_cmd_buffer);
059ec3d9
PH
3358 done = 1;
3359 }
3360
3361 break;
3362 }
3363
3364 /* If sender_host_unknown is true, we have got here via the -bs interface,
3365 not called from inetd. Otherwise, we are running an IP connection and the
3366 host address will be set. If the helo name is the primary name of this
3367 host and we haven't done a reverse lookup, force one now. If helo_required
3368 is set, ensure that the HELO name matches the actual host. If helo_verify
3369 is set, do the same check, but softly. */
3370
3371 if (!sender_host_unknown)
3372 {
3373 BOOL old_helo_verified = helo_verified;
ca86f471 3374 uschar *p = smtp_cmd_data;
059ec3d9
PH
3375
3376 while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; }
3377 *p = 0;
3378
3379 /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
3380 because otherwise the log can be confusing. */
3381
3382 if (sender_host_name == NULL &&
3383 (deliver_domain = sender_helo_name, /* set $domain */
3384 match_isinlist(sender_helo_name, &helo_lookup_domains, 0,
3385 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL)) == OK)
3386 (void)host_name_lookup();
3387
3388 /* Rebuild the fullhost info to include the HELO name (and the real name
3389 if it was looked up.) */
3390
3391 host_build_sender_fullhost(); /* Rebuild */
3392 set_process_info("handling%s incoming connection from %s",
817d9f57 3393 (tls_in.active >= 0)? " TLS" : "", host_and_ident(FALSE));
059ec3d9
PH
3394
3395 /* Verify if configured. This doesn't give much security, but it does
d7b47fd0
PH
3396 make some people happy to be able to do it. If helo_required is set,
3397 (host matches helo_verify_hosts) failure forces rejection. If helo_verify
3398 is set (host matches helo_try_verify_hosts), it does not. This is perhaps
3399 now obsolescent, since the verification can now be requested selectively
3400 at ACL time. */
059ec3d9 3401
d7b47fd0 3402 helo_verified = helo_verify_failed = FALSE;
059ec3d9
PH
3403 if (helo_required || helo_verify)
3404 {
d7b47fd0 3405 BOOL tempfail = !smtp_verify_helo();
059ec3d9
PH
3406 if (!helo_verified)
3407 {
3408 if (helo_required)
3409 {
3410 smtp_printf("%d %s argument does not match calling host\r\n",
3411 tempfail? 451 : 550, hello);
3412 log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s",
3413 tempfail? "temporarily " : "",
3414 hello, sender_helo_name, host_and_ident(FALSE));
3415 helo_verified = old_helo_verified;
3416 break; /* End of HELO/EHLO processing */
3417 }
3418 HDEBUG(D_all) debug_printf("%s verification failed but host is in "
3419 "helo_try_verify_hosts\n", hello);
3420 }
3421 }
3422 }
3423
8523533c
TK
3424#ifdef EXPERIMENTAL_SPF
3425 /* set up SPF context */
3426 spf_init(sender_helo_name, sender_host_address);
3427#endif
3428
a14e5636
PH
3429 /* Apply an ACL check if one is defined; afterwards, recheck
3430 synchronization in case the client started sending in a delay. */
059ec3d9
PH
3431
3432 if (acl_smtp_helo != NULL)
3433 {
64ffc24f 3434 rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, &user_msg, &log_msg);
059ec3d9
PH
3435 if (rc != OK)
3436 {
3437 done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg);
3438 sender_helo_name = NULL;
3439 host_build_sender_fullhost(); /* Rebuild */
3440 break;
3441 }
a14e5636 3442 else if (!check_sync()) goto SYNC_FAILURE;
059ec3d9
PH
3443 }
3444
4e88a19f
PH
3445 /* Generate an OK reply. The default string includes the ident if present,
3446 and also the IP address if present. Reflecting back the ident is intended
3447 as a deterrent to mail forgers. For maximum efficiency, and also because
3448 some broken systems expect each response to be in a single packet, arrange
3449 that the entire reply is sent in one write(). */
059ec3d9
PH
3450
3451 auth_advertised = FALSE;
3452 pipelining_advertised = FALSE;
3453 #ifdef SUPPORT_TLS
3454 tls_advertised = FALSE;
3455 #endif
3456
d6a96edc 3457 smtp_code = US"250 "; /* Default response code plus space*/
4e88a19f
PH
3458 if (user_msg == NULL)
3459 {
3460 s = string_sprintf("%.3s %s Hello %s%s%s",
3461 smtp_code,
3462 smtp_active_hostname,
3463 (sender_ident == NULL)? US"" : sender_ident,
3464 (sender_ident == NULL)? US"" : US" at ",
3465 (sender_host_name == NULL)? sender_helo_name : sender_host_name);
3466
3467 ptr = Ustrlen(s);
3468 size = ptr + 1;
059ec3d9 3469
4e88a19f
PH
3470 if (sender_host_address != NULL)
3471 {
3472 s = string_cat(s, &size, &ptr, US" [", 2);
3473 s = string_cat(s, &size, &ptr, sender_host_address,
3474 Ustrlen(sender_host_address));
3475 s = string_cat(s, &size, &ptr, US"]", 1);
3476 }
3477 }
3478
d6a96edc
PH
3479 /* A user-supplied EHLO greeting may not contain more than one line. Note
3480 that the code returned by smtp_message_code() includes the terminating
3481 whitespace character. */
059ec3d9 3482
4e88a19f 3483 else
059ec3d9 3484 {
4e88a19f 3485 char *ss;
d6a96edc 3486 int codelen = 4;
4e88a19f 3487 smtp_message_code(&smtp_code, &codelen, &user_msg, NULL);
d6a96edc 3488 s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg);
4e88a19f
PH
3489 if ((ss = strpbrk(CS s, "\r\n")) != NULL)
3490 {
3491 log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain "
3492 "newlines: message truncated: %s", string_printing(s));
3493 *ss = 0;
3494 }
3495 ptr = Ustrlen(s);
3496 size = ptr + 1;
059ec3d9
PH
3497 }
3498
3499 s = string_cat(s, &size, &ptr, US"\r\n", 2);
3500
3501 /* If we received EHLO, we must create a multiline response which includes
3502 the functions supported. */
3503
3504 if (esmtp)
3505 {
3506 s[3] = '-';
3507
3508 /* I'm not entirely happy with this, as an MTA is supposed to check
3509 that it has enough room to accept a message of maximum size before
3510 it sends this. However, there seems little point in not sending it.
3511 The actual size check happens later at MAIL FROM time. By postponing it
3512 till then, VRFY and EXPN can be used after EHLO when space is short. */
3513
3514 if (thismessage_size_limit > 0)
3515 {
4e88a19f
PH
3516 sprintf(CS big_buffer, "%.3s-SIZE %d\r\n", smtp_code,
3517 thismessage_size_limit);
059ec3d9
PH
3518 s = string_cat(s, &size, &ptr, big_buffer, Ustrlen(big_buffer));
3519 }
3520 else
3521 {
4e88a19f
PH
3522 s = string_cat(s, &size, &ptr, smtp_code, 3);
3523 s = string_cat(s, &size, &ptr, US"-SIZE\r\n", 7);
059ec3d9
PH
3524 }
3525
3526 /* Exim does not do protocol conversion or data conversion. It is 8-bit
3527 clean; if it has an 8-bit character in its hand, it just sends it. It
3528 cannot therefore specify 8BITMIME and remain consistent with the RFCs.
3529 However, some users want this option simply in order to stop MUAs
3530 mangling messages that contain top-bit-set characters. It is therefore
3531 provided as an option. */
3532
3533 if (accept_8bitmime)
4e88a19f
PH
3534 {
3535 s = string_cat(s, &size, &ptr, smtp_code, 3);
3536 s = string_cat(s, &size, &ptr, US"-8BITMIME\r\n", 11);
3537 }
059ec3d9
PH
3538
3539 /* Advertise ETRN if there's an ACL checking whether a host is
3540 permitted to issue it; a check is made when any host actually tries. */
3541
3542 if (acl_smtp_etrn != NULL)
3543 {
4e88a19f
PH
3544 s = string_cat(s, &size, &ptr, smtp_code, 3);
3545 s = string_cat(s, &size, &ptr, US"-ETRN\r\n", 7);
059ec3d9
PH
3546 }
3547
3548 /* Advertise EXPN if there's an ACL checking whether a host is
3549 permitted to issue it; a check is made when any host actually tries. */
3550
3551 if (acl_smtp_expn != NULL)
3552 {
4e88a19f
PH
3553 s = string_cat(s, &size, &ptr, smtp_code, 3);
3554 s = string_cat(s, &size, &ptr, US"-EXPN\r\n", 7);
059ec3d9
PH
3555 }
3556
3557 /* Exim is quite happy with pipelining, so let the other end know that
3558 it is safe to use it, unless advertising is disabled. */
3559
cf8b11a5
PH
3560 if (pipelining_enable &&
3561 verify_check_host(&pipelining_advertise_hosts) == OK)
059ec3d9 3562 {
4e88a19f
PH
3563 s = string_cat(s, &size, &ptr, smtp_code, 3);
3564 s = string_cat(s, &size, &ptr, US"-PIPELINING\r\n", 13);
059ec3d9
PH
3565 sync_cmd_limit = NON_SYNC_CMD_PIPELINING;
3566 pipelining_advertised = TRUE;
3567 }
3568
fd98a5c6 3569
059ec3d9
PH
3570 /* If any server authentication mechanisms are configured, advertise
3571 them if the current host is in auth_advertise_hosts. The problem with
3572 advertising always is that some clients then require users to
3573 authenticate (and aren't configurable otherwise) even though it may not
3574 be necessary (e.g. if the host is in host_accept_relay).
3575
3576 RFC 2222 states that SASL mechanism names contain only upper case
3577 letters, so output the names in upper case, though we actually recognize
3578 them in either case in the AUTH command. */
3579
3580 if (auths != NULL)
3581 {
3582 if (verify_check_host(&auth_advertise_hosts) == OK)
3583 {
3584 auth_instance *au;
3585 BOOL first = TRUE;
3586 for (au = auths; au != NULL; au = au->next)
3587 {
3588 if (au->server && (au->advertise_condition == NULL ||
3589 expand_check_condition(au->advertise_condition, au->name,
3590 US"authenticator")))
3591 {
3592 int saveptr;
3593 if (first)
3594 {
4e88a19f
PH
3595 s = string_cat(s, &size, &ptr, smtp_code, 3);
3596 s = string_cat(s, &size, &ptr, US"-AUTH", 5);
059ec3d9
PH
3597 first = FALSE;
3598 auth_advertised = TRUE;
3599 }
3600 saveptr = ptr;
3601 s = string_cat(s, &size, &ptr, US" ", 1);
3602 s = string_cat(s, &size, &ptr, au->public_name,
3603 Ustrlen(au->public_name));
3604 while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]);
3605 au->advertised = TRUE;
3606 }
3607 else au->advertised = FALSE;
3608 }
3609 if (!first) s = string_cat(s, &size, &ptr, US"\r\n", 2);
3610 }
3611 }
3612
3613 /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
3614 if it has been included in the binary, and the host matches
3615 tls_advertise_hosts. We must *not* advertise if we are already in a
3616 secure connection. */
3617
3618 #ifdef SUPPORT_TLS
817d9f57 3619 if (tls_in.active < 0 &&
059ec3d9
PH
3620 verify_check_host(&tls_advertise_hosts) != FAIL)
3621 {
4e88a19f
PH
3622 s = string_cat(s, &size, &ptr, smtp_code, 3);
3623 s = string_cat(s, &size, &ptr, US"-STARTTLS\r\n", 11);
059ec3d9
PH
3624 tls_advertised = TRUE;
3625 }
3626 #endif
3627
fd98a5c6
JH
3628 #ifdef EXPERIMENTAL_PRDR
3629 /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */
3630 if (prdr_enable) {
3631 s = string_cat(s, &size, &ptr, smtp_code, 3);
3632 s = string_cat(s, &size, &ptr, US"-PRDR\r\n", 7);
3633 }
3634 #endif
3635
059ec3d9
PH
3636 /* Finish off the multiline reply with one that is always available. */
3637
4e88a19f
PH
3638 s = string_cat(s, &size, &ptr, smtp_code, 3);
3639 s = string_cat(s, &size, &ptr, US" HELP\r\n", 7);
059ec3d9
PH
3640 }
3641
3642 /* Terminate the string (for debug), write it, and note that HELO/EHLO
3643 has been seen. */
3644
3645 s[ptr] = 0;
3646
3647 #ifdef SUPPORT_TLS
817d9f57 3648 if (tls_in.active >= 0) (void)tls_write(TRUE, s, ptr); else
059ec3d9
PH
3649 #endif
3650
1ac6b2e7
JH
3651 {
3652 int i = fwrite(s, 1, ptr, smtp_out); i = i; /* compiler quietening */
3653 }
898d150f
PH
3654 DEBUG(D_receive)
3655 {
3656 uschar *cr;
3657 while ((cr = Ustrchr(s, '\r')) != NULL) /* lose CRs */
3658 memmove(cr, cr + 1, (ptr--) - (cr - s));
3659 debug_printf("SMTP>> %s", s);
3660 }
059ec3d9 3661 helo_seen = TRUE;
4e88a19f
PH
3662
3663 /* Reset the protocol and the state, abandoning any previous message. */
3664
3665 received_protocol = (esmtp?
3666 protocols[pextend +
3667 ((sender_host_authenticated != NULL)? pauthed : 0) +
817d9f57 3668 ((tls_in.active >= 0)? pcrpted : 0)]
4e88a19f 3669 :
817d9f57 3670 protocols[pnormal + ((tls_in.active >= 0)? pcrpted : 0)])
4e88a19f
PH
3671 +
3672 ((sender_host_address != NULL)? pnlocal : 0);
3673
3674 smtp_reset(reset_point);
3675 toomany = FALSE;
059ec3d9
PH
3676 break; /* HELO/EHLO */
3677
3678
3679 /* The MAIL command requires an address as an operand. All we do
3680 here is to parse it for syntactic correctness. The form "<>" is
3681 a special case which converts into an empty string. The start/end
3682 pointers in the original are not used further for this address, as
3683 it is the canonical extracted address which is all that is kept. */
3684
3685 case MAIL_CMD:
b4ed4da0 3686 HAD(SCH_MAIL);
059ec3d9
PH
3687 smtp_mailcmd_count++; /* Count for limit and ratelimit */
3688 was_rej_mail = TRUE; /* Reset if accepted */
d27f98fe 3689 env_mail_type_t * mail_args; /* Sanity check & validate args */
059ec3d9
PH
3690
3691 if (helo_required && !helo_seen)
3692 {
3693 smtp_printf("503 HELO or EHLO required\r\n");
3694 log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no "
3695 "HELO/EHLO given", host_and_ident(FALSE));
3696 break;
3697 }
3698
3699 if (sender_address != NULL)
3700 {
3701 done = synprot_error(L_smtp_protocol_error, 503, NULL,
3702 US"sender already given");
3703 break;
3704 }
3705
ca86f471 3706 if (smtp_cmd_data[0] == 0)
059ec3d9
PH
3707 {
3708 done = synprot_error(L_smtp_protocol_error, 501, NULL,
3709 US"MAIL must have an address operand");
3710 break;
3711 }
3712
3713 /* Check to see if the limit for messages per connection would be
3714 exceeded by accepting further messages. */
3715
3716 if (smtp_accept_max_per_connection > 0 &&
3717 smtp_mailcmd_count > smtp_accept_max_per_connection)
3718 {
3719 smtp_printf("421 too many messages in this connection\r\n");
3720 log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many "
3721 "messages in one connection", host_and_ident(TRUE));
3722 break;
3723 }
3724
3725 /* Reset for start of message - even if this is going to fail, we
3726 obviously need to throw away any previous data. */
3727
3728 smtp_reset(reset_point);
3729 toomany = FALSE;
3730 sender_data = recipient_data = NULL;
3731
3732 /* Loop, checking for ESMTP additions to the MAIL FROM command. */
3733
3734 if (esmtp) for(;;)
3735 {
3736 uschar *name, *value, *end;
3737 unsigned long int size;
d27f98fe 3738 BOOL arg_error = FALSE;
059ec3d9
PH
3739
3740 if (!extract_option(&name, &value)) break;
3741
d27f98fe
TL
3742 for (mail_args = env_mail_type_list;
3743 (char *)mail_args < (char *)env_mail_type_list + sizeof(env_mail_type_list);
3744 mail_args++
3745 )
059ec3d9 3746 {
d27f98fe
TL
3747 if (strcmpic(name, mail_args->name) == 0)
3748 break;
059ec3d9 3749 }
d27f98fe
TL
3750 if (mail_args->need_value && strcmpic(value, US"") == 0)
3751 break;
059ec3d9 3752
d27f98fe 3753 switch(mail_args->value)
059ec3d9 3754 {
d27f98fe
TL
3755 /* Handle SIZE= by reading the value. We don't do the check till later,
3756 in order to be able to log the sender address on failure. */
3757 case ENV_MAIL_OPT_SIZE:
d27f98fe 3758 if (((size = Ustrtoul(value, &end, 10)), *end == 0))
059ec3d9 3759 {
d27f98fe
TL
3760 if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX)
3761 size = INT_MAX;
3762 message_size = (int)size;
059ec3d9
PH
3763 }
3764 else
d27f98fe
TL
3765 arg_error = TRUE;
3766 break;
059ec3d9 3767
d27f98fe
TL
3768 /* If this session was initiated with EHLO and accept_8bitmime is set,
3769 Exim will have indicated that it supports the BODY=8BITMIME option. In
3770 fact, it does not support this according to the RFCs, in that it does not
3771 take any special action for forwarding messages containing 8-bit
3772 characters. That is why accept_8bitmime is not the default setting, but
3773 some sites want the action that is provided. We recognize both "8BITMIME"
3774 and "7BIT" as body types, but take no action. */
3775 case ENV_MAIL_OPT_BODY:
3c0a92dc
JH
3776 if (accept_8bitmime) {
3777 if (strcmpic(value, US"8BITMIME") == 0) {
3778 body_8bitmime = 8;
3779 } else if (strcmpic(value, US"7BIT") == 0) {
3780 body_8bitmime = 7;
3781 } else {
3782 body_8bitmime = 0;
3783 done = synprot_error(L_smtp_syntax_error, 501, NULL,
3784 US"invalid data for BODY");
3785 goto COMMAND_LOOP;
3786 }
3787 DEBUG(D_receive) debug_printf("8BITMIME: %d\n", body_8bitmime);
3788 break;
3789 }
d27f98fe
TL
3790 arg_error = TRUE;
3791 break;
059ec3d9 3792
d27f98fe
TL
3793 /* Handle the AUTH extension. If the value given is not "<>" and either
3794 the ACL says "yes" or there is no ACL but the sending host is
3795 authenticated, we set it up as the authenticated sender. However, if the
3796 authenticator set a condition to be tested, we ignore AUTH on MAIL unless
3797 the condition is met. The value of AUTH is an xtext, which means that +,
3798 = and cntrl chars are coded in hex; however "<>" is unaffected by this
3799 coding. */
3800 case ENV_MAIL_OPT_AUTH:
3801 if (Ustrcmp(value, "<>") != 0)
3802 {
3803 int rc;
3804 uschar *ignore_msg;
059ec3d9 3805
d27f98fe
TL
3806 if (auth_xtextdecode(value, &authenticated_sender) < 0)
3807 {
3808 /* Put back terminator overrides for error message */
d27f98fe 3809 value[-1] = '=';
fd98a5c6 3810 name[-1] = ' ';
d27f98fe
TL
3811 done = synprot_error(L_smtp_syntax_error, 501, NULL,
3812 US"invalid data for AUTH");
3813 goto COMMAND_LOOP;
3814 }
3815 if (acl_smtp_mailauth == NULL)
3816 {
3817 ignore_msg = US"client not authenticated";
3818 rc = (sender_host_authenticated != NULL)? OK : FAIL;
3819 }
3820 else
3821 {
3822 ignore_msg = US"rejected by ACL";