Fix build on FreeBSD 11
[exim.git] / src / src / smtp_in.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
f9ba5e22 5/* Copyright (c) University of Cambridge 1995 - 2018 */
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6/* See the file NOTICE for conditions of use and distribution. */
7
8/* Functions for handling an incoming SMTP call. */
9
10
11#include "exim.h"
2ef7ed08 12#include <assert.h>
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13
14
15/* Initialize for TCP wrappers if so configured. It appears that the macro
16HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before
17including that header, and restore its value afterwards. */
18
19#ifdef USE_TCP_WRAPPERS
20
21 #if HAVE_IPV6
22 #define EXIM_HAVE_IPV6
23 #endif
24 #undef HAVE_IPV6
25 #include <tcpd.h>
26 #undef HAVE_IPV6
27 #ifdef EXIM_HAVE_IPV6
28 #define HAVE_IPV6 TRUE
29 #endif
30
31int allow_severity = LOG_INFO;
32int deny_severity = LOG_NOTICE;
5dc43717 33uschar *tcp_wrappers_name;
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34#endif
35
36
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37/* Size of buffer for reading SMTP commands. We used to use 512, as defined
38by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
39commands that accept arguments, and this in particular applies to AUTH, where
94431adb 40the data can be quite long. More recently this value was 2048 in Exim;
e2ca7082 41however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients
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42such as Thunderbird will send an AUTH with an initial-response for GSSAPI.
43The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and
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44we need room to handle large base64-encoded AUTHs for GSSAPI.
45*/
46
bd8fbe36 47#define SMTP_CMD_BUFFER_SIZE 16384
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48
49/* Size of buffer for reading SMTP incoming packets */
50
bd8fbe36 51#define IN_BUFFER_SIZE 8192
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52
53/* Structure for SMTP command list */
54
55typedef struct {
1ba28e2b 56 const char *name;
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57 int len;
58 short int cmd;
59 short int has_arg;
60 short int is_mail_cmd;
61} smtp_cmd_list;
62
63/* Codes for identifying commands. We order them so that those that come first
64are those for which synchronization is always required. Checking this can help
65block some spam. */
66
67enum {
68 /* These commands are required to be synchronized, i.e. to be the last in a
69 block of commands when pipelining. */
70
71 HELO_CMD, EHLO_CMD, DATA_CMD, /* These are listed in the pipelining */
72 VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */
73 ETRN_CMD, /* This by analogy with TURN from the RFC */
74 STARTTLS_CMD, /* Required by the STARTTLS RFC */
b3ef41c9 75 TLS_AUTH_CMD, /* auto-command at start of SSL */
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76
77 /* This is a dummy to identify the non-sync commands when pipelining */
78
79 NON_SYNC_CMD_PIPELINING,
80
81 /* These commands need not be synchronized when pipelining */
82
83 MAIL_CMD, RCPT_CMD, RSET_CMD,
84
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85 /* This is a dummy to identify the non-sync commands when not pipelining */
86
87 NON_SYNC_CMD_NON_PIPELINING,
88
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89 /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and
90 processed the message is sent using a series of BDAT commands"
91 implies that BDAT should be synchronized. However, we see Google, at least,
92 sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for
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93 processing of the RCPT response(s). We shall do the same, and not require
94 synch for BDAT. Worse, as the chunk may (very likely will) follow the
95 command-header in the same packet we cannot do the usual "is there any
4c04137d 96 follow-on data after the command line" even for non-pipeline mode.
f4630439 97 So we'll need an explicit check after reading the expected chunk amount
4c04137d 98 when non-pipe, before sending the ACK. */
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99
100 BDAT_CMD,
101
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102 /* I have been unable to find a statement about the use of pipelining
103 with AUTH, so to be on the safe side it is here, though I kind of feel
104 it should be up there with the synchronized commands. */
105
106 AUTH_CMD,
107
108 /* I'm not sure about these, but I don't think they matter. */
109
110 QUIT_CMD, HELP_CMD,
111
cee5f132 112#ifdef SUPPORT_PROXY
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113 PROXY_FAIL_IGNORE_CMD,
114#endif
115
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116 /* These are specials that don't correspond to actual commands */
117
118 EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD,
119 TOO_MANY_NONMAIL_CMD };
120
121
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122/* This is a convenience macro for adding the identity of an SMTP command
123to the circular buffer that holds a list of the last n received. */
124
125#define HAD(n) \
126 smtp_connection_had[smtp_ch_index++] = n; \
127 if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
128
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129
130/*************************************************
131* Local static variables *
132*************************************************/
133
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134static struct {
135 BOOL auth_advertised :1;
059ec3d9 136#ifdef SUPPORT_TLS
88752192 137 BOOL tls_advertised :1;
8ac90765 138# ifdef EXPERIMENTAL_REQUIRETLS
88752192 139 BOOL requiretls_advertised :1;
8ac90765 140# endif
059ec3d9 141#endif
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142 BOOL dsn_advertised :1;
143 BOOL esmtp :1;
144 BOOL helo_required :1;
145 BOOL helo_verify :1;
146 BOOL helo_seen :1;
147 BOOL helo_accept_junk :1;
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148#ifdef EXPERIMENTAL_PIPE_CONNECT
149 BOOL pipe_connect_acceptable :1;
150#endif
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151 BOOL rcpt_smtp_response_same :1;
152 BOOL rcpt_in_progress :1;
153 BOOL smtp_exit_function_called :1;
8c5d388a 154#ifdef SUPPORT_I18N
88752192 155 BOOL smtputf8_advertised :1;
d1a13eea 156#endif
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157} fl = {
158 .helo_required = FALSE,
159 .helo_verify = FALSE,
160 .smtp_exit_function_called = FALSE,
161};
162
163static auth_instance *authenticated_by;
164static int count_nonmail;
165static int nonmail_command_count;
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166static int synprot_error_count;
167static int unknown_command_count;
168static int sync_cmd_limit;
169static int smtp_write_error = 0;
170
2679d413 171static uschar *rcpt_smtp_response;
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172static uschar *smtp_data_buffer;
173static uschar *smtp_cmd_data;
174
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175/* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
176final fields of all except AUTH are forced TRUE at the start of a new message
177setup, to allow one of each between messages that is not counted as a nonmail
178command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to
179allow a new EHLO after starting up TLS.
180
181AUTH is "falsely" labelled as a mail command initially, so that it doesn't get
182counted. However, the flag is changed when AUTH is received, so that multiple
183failing AUTHs will eventually hit the limit. After a successful AUTH, another
184AUTH is already forbidden. After a TLS session is started, AUTH's flag is again
185forced TRUE, to allow for the re-authentication that can happen at that point.
186
187QUIT is also "falsely" labelled as a mail command so that it doesn't up the
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188count of non-mail commands and possibly provoke an error.
189
190tls_auth is a pseudo-command, never expected in input. It is activated
191on TLS startup and looks for a tls authenticator. */
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192
193static smtp_cmd_list cmd_list[] = {
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194 /* name len cmd has_arg is_mail_cmd */
195
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196 { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */
197 { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE },
198 { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE },
199 { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
e0574cb5 200#ifdef SUPPORT_TLS
059ec3d9 201 { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
69d8eed7 202 { "tls_auth", 0, TLS_AUTH_CMD, FALSE, FALSE },
e0574cb5 203#endif
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204
205/* If you change anything above here, also fix the definitions below. */
206
207 { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE },
208 { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE },
209 { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE },
18481de3 210 { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE },
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211 { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE },
212 { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE },
213 { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE },
214 { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE },
215 { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE },
216 { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE }
217};
218
219static smtp_cmd_list *cmd_list_end =
220 cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list);
221
222#define CMD_LIST_RSET 0
223#define CMD_LIST_HELO 1
224#define CMD_LIST_EHLO 2
225#define CMD_LIST_AUTH 3
226#define CMD_LIST_STARTTLS 4
b3ef41c9 227#define CMD_LIST_TLS_AUTH 5
059ec3d9 228
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229/* This list of names is used for performing the smtp_no_mail logging action.
230It must be kept in step with the SCH_xxx enumerations. */
231
232static uschar *smtp_names[] =
233 {
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234 US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN",
235 US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET",
236 US"STARTTLS", US"VRFY" };
b4ed4da0 237
e524074d 238static uschar *protocols_local[] = {
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239 US"local-smtp", /* HELO */
240 US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
241 US"local-esmtp", /* EHLO */
242 US"local-esmtps", /* EHLO->STARTTLS->EHLO */
243 US"local-esmtpa", /* EHLO->AUTH */
244 US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
059ec3d9 245 };
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246static uschar *protocols[] = {
247 US"smtp", /* HELO */
248 US"smtps", /* The rare case EHLO->STARTTLS->HELO */
249 US"esmtp", /* EHLO */
250 US"esmtps", /* EHLO->STARTTLS->EHLO */
251 US"esmtpa", /* EHLO->AUTH */
252 US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
253 };
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254
255#define pnormal 0
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256#define pextend 2
257#define pcrpted 1 /* added to pextend or pnormal */
258#define pauthed 2 /* added to pextend */
059ec3d9 259
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260/* Sanity check and validate optional args to MAIL FROM: envelope */
261enum {
2ef7ed08 262 ENV_MAIL_OPT_NULL,
d27f98fe 263 ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH,
8ccd00b1 264#ifndef DISABLE_PRDR
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265 ENV_MAIL_OPT_PRDR,
266#endif
6c1c3d1d 267 ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID,
8c5d388a 268#ifdef SUPPORT_I18N
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269 ENV_MAIL_OPT_UTF8,
270#endif
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271#ifdef EXPERIMENTAL_REQUIRETLS
272 ENV_MAIL_OPT_REQTLS,
273#endif
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274 };
275typedef struct {
276 uschar * name; /* option requested during MAIL cmd */
277 int value; /* enum type */
278 BOOL need_value; /* TRUE requires value (name=value pair format)
279 FALSE is a singleton */
280 } env_mail_type_t;
281static env_mail_type_t env_mail_type_list[] = {
282 { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE },
283 { US"BODY", ENV_MAIL_OPT_BODY, TRUE },
284 { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE },
8ccd00b1 285#ifndef DISABLE_PRDR
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286 { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE },
287#endif
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288 { US"RET", ENV_MAIL_OPT_RET, TRUE },
289 { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE },
8c5d388a 290#ifdef SUPPORT_I18N
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291 { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */
292#endif
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293#ifdef EXPERIMENTAL_REQUIRETLS
294 /* https://tools.ietf.org/html/draft-ietf-uta-smtp-require-tls-03 */
295 { US"REQUIRETLS",ENV_MAIL_OPT_REQTLS, FALSE },
296#endif
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297 /* keep this the last entry */
298 { US"NULL", ENV_MAIL_OPT_NULL, FALSE },
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299 };
300
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301/* When reading SMTP from a remote host, we have to use our own versions of the
302C input-reading functions, in order to be able to flush the SMTP output only
303when about to read more data from the socket. This is the only way to get
304optimal performance when the client is using pipelining. Flushing for every
305command causes a separate packet and reply packet each time; saving all the
306responses up (when pipelining) combines them into one packet and one response.
307
308For simplicity, these functions are used for *all* SMTP input, not only when
309receiving over a socket. However, after setting up a secure socket (SSL), input
310is read via the OpenSSL library, and another set of functions is used instead
311(see tls.c).
312
313These functions are set in the receive_getc etc. variables and called with the
314same interface as the C functions. However, since there can only ever be
315one incoming SMTP call, we just use a single buffer and flags. There is no need
316to implement a complicated private FILE-like structure.*/
317
318static uschar *smtp_inbuffer;
319static uschar *smtp_inptr;
320static uschar *smtp_inend;
321static int smtp_had_eof;
322static int smtp_had_error;
323
324
7e3ce68e 325/* forward declarations */
bd8fbe36 326static int smtp_read_command(BOOL check_sync, unsigned buffer_lim);
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327static int synprot_error(int type, int code, uschar *data, uschar *errmess);
328static void smtp_quit_handler(uschar **, uschar **);
329static void smtp_rset_handler(void);
330
059ec3d9 331/*************************************************
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332* Recheck synchronization *
333*************************************************/
334
335/* Synchronization checks can never be perfect because a packet may be on its
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336way but not arrived when the check is done. Normally, the checks happen when
337commands are read: Exim ensures that there is no more input in the input buffer.
338In normal cases, the response to the command will be fast, and there is no
339further check.
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340
341However, for some commands an ACL is run, and that can include delays. In those
342cases, it is useful to do another check on the input just before sending the
343response. This also applies at the start of a connection. This function does
344that check by means of the select() function, as long as the facility is not
345disabled or inappropriate. A failure of select() is ignored.
346
347When there is unwanted input, we read it so that it appears in the log of the
348error.
349
350Arguments: none
351Returns: TRUE if all is well; FALSE if there is input pending
352*/
353
354static BOOL
925ac8e4 355wouldblock_reading(void)
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356{
357int fd, rc;
358fd_set fds;
359struct timeval tzero;
360
9067f574 361#ifdef SUPPORT_TLS
74f1a423 362if (tls_in.active.sock >= 0)
e5de01f0 363 return !tls_could_read();
9067f574 364#endif
f4630439 365
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366if (smtp_inptr < smtp_inend)
367 return FALSE;
368
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369fd = fileno(smtp_in);
370FD_ZERO(&fds);
371FD_SET(fd, &fds);
372tzero.tv_sec = 0;
373tzero.tv_usec = 0;
374rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero);
375
376if (rc <= 0) return TRUE; /* Not ready to read */
bd8fbe36 377rc = smtp_getc(GETC_BUFFER_UNLIMITED);
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378if (rc < 0) return TRUE; /* End of file or error */
379
380smtp_ungetc(rc);
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381return FALSE;
382}
383
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384static BOOL
385check_sync(void)
386{
8768d548 387if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket)
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388 return TRUE;
389
390return wouldblock_reading();
391}
392
393
394/* If there's input waiting (and we're doing pipelineing) then we can pipeline
395a reponse with the one following. */
396
397static BOOL
398pipeline_response(void)
399{
400if ( !smtp_enforce_sync || !sender_host_address
8768d548 401 || f.sender_host_notsocket || !f.smtp_in_pipelining_advertised)
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402 return FALSE;
403
3fc73bdc 404if (wouldblock_reading()) return FALSE;
8768d548 405f.smtp_in_pipelining_used = TRUE;
3fc73bdc 406return TRUE;
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407}
408
f4630439 409
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410#ifdef EXPERIMENTAL_PIPE_CONNECT
411static BOOL
412pipeline_connect_sends(void)
413{
414if (!sender_host_address || f.sender_host_notsocket || !fl.pipe_connect_acceptable)
415 return FALSE;
416
417if (wouldblock_reading()) return FALSE;
418f.smtp_in_early_pipe_used = TRUE;
419return TRUE;
420}
421#endif
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422
423/*************************************************
424* Log incomplete transactions *
425*************************************************/
426
427/* This function is called after a transaction has been aborted by RSET, QUIT,
428connection drops or other errors. It logs the envelope information received
429so far in order to preserve address verification attempts.
430
431Argument: string to indicate what aborted the transaction
432Returns: nothing
433*/
434
435static void
436incomplete_transaction_log(uschar *what)
437{
438if (sender_address == NULL || /* No transaction in progress */
439 !LOGGING(smtp_incomplete_transaction))
440 return;
441
442/* Build list of recipients for logging */
443
444if (recipients_count > 0)
445 {
446 int i;
447 raw_recipients = store_get(recipients_count * sizeof(uschar *));
448 for (i = 0; i < recipients_count; i++)
449 raw_recipients[i] = recipients_list[i].address;
450 raw_recipients_count = recipients_count;
451 }
452
453log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS,
454 "%s incomplete transaction (%s)", host_and_ident(TRUE), what);
455}
456
457
458
459
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460void
461smtp_command_timeout_exit(void)
462{
463log_write(L_lost_incoming_connection,
464 LOG_MAIN, "SMTP command timeout on%s connection from %s",
74f1a423 465 tls_in.active.sock >= 0 ? " TLS" : "", host_and_ident(FALSE));
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466if (smtp_batched_input)
467 moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */
468smtp_notquit_exit(US"command-timeout", US"421",
469 US"%s: SMTP command timeout - closing connection",
470 smtp_active_hostname);
471exim_exit(EXIT_FAILURE, US"receiving");
472}
473
474void
475smtp_command_sigterm_exit(void)
476{
477log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info());
478if (smtp_batched_input)
479 moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */
480smtp_notquit_exit(US"signal-exit", US"421",
481 US"%s: Service not available - closing connection", smtp_active_hostname);
482exim_exit(EXIT_FAILURE, US"receiving");
483}
484
485void
486smtp_data_timeout_exit(void)
487{
488log_write(L_lost_incoming_connection,
489 LOG_MAIN, "SMTP data timeout (message abandoned) on connection from %s F=<%s>",
490 sender_fullhost ? sender_fullhost : US"local process", sender_address);
491receive_bomb_out(US"data-timeout", US"SMTP incoming data timeout");
492/* Does not return */
493}
494
495void
496smtp_data_sigint_exit(void)
497{
498log_write(0, LOG_MAIN, "%s closed after %s",
499 smtp_get_connection_info(), had_data_sigint == SIGTERM ? "SIGTERM":"SIGINT");
500receive_bomb_out(US"signal-exit",
501 US"Service not available - SIGTERM or SIGINT received");
502/* Does not return */
503}
504
505
506
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507/* Refill the buffer, and notify DKIM verification code.
508Return false for error or EOF.
509*/
510
511static BOOL
512smtp_refill(unsigned lim)
513{
514int rc, save_errno;
515if (!smtp_out) return FALSE;
516fflush(smtp_out);
c2a1bba0 517if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
0d81dabc 518
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519/* Limit amount read, so non-message data is not fed to DKIM.
520Take care to not touch the safety NUL at the end of the buffer. */
0d81dabc 521
ecce6d9a 522rc = read(fileno(smtp_in), smtp_inbuffer, MIN(IN_BUFFER_SIZE-1, lim));
0d81dabc 523save_errno = errno;
c2a1bba0 524if (smtp_receive_timeout > 0) ALARM_CLR(0);
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525if (rc <= 0)
526 {
527 /* Must put the error text in fixed store, because this might be during
528 header reading, where it releases unused store above the header. */
529 if (rc < 0)
530 {
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531 if (had_command_timeout) /* set by signal handler */
532 smtp_command_timeout_exit(); /* does not return */
533 if (had_command_sigterm)
534 smtp_command_sigterm_exit();
535 if (had_data_timeout)
536 smtp_data_timeout_exit();
537 if (had_data_sigint)
538 smtp_data_sigint_exit();
539
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540 smtp_had_error = save_errno;
541 smtp_read_error = string_copy_malloc(
542 string_sprintf(" (error: %s)", strerror(save_errno)));
543 }
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544 else
545 smtp_had_eof = 1;
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546 return FALSE;
547 }
548#ifndef DISABLE_DKIM
549dkim_exim_verify_feed(smtp_inbuffer, rc);
550#endif
551smtp_inend = smtp_inbuffer + rc;
552smtp_inptr = smtp_inbuffer;
553return TRUE;
554}
555
f4630439 556/*************************************************
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557* SMTP version of getc() *
558*************************************************/
559
560/* This gets the next byte from the SMTP input buffer. If the buffer is empty,
561it flushes the output, and refills the buffer, with a timeout. The signal
562handler is set appropriately by the calling function. This function is not used
4c04137d 563after a connection has negotiated itself into an TLS/SSL state.
059ec3d9 564
bd8fbe36 565Arguments: lim Maximum amount to read/buffer
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566Returns: the next character or EOF
567*/
568
569int
bd8fbe36 570smtp_getc(unsigned lim)
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571{
572if (smtp_inptr >= smtp_inend)
0d81dabc 573 if (!smtp_refill(lim))
059ec3d9 574 return EOF;
059ec3d9
PH
575return *smtp_inptr++;
576}
577
0d81dabc
JH
578uschar *
579smtp_getbuf(unsigned * len)
580{
581unsigned size;
582uschar * buf;
583
584if (smtp_inptr >= smtp_inend)
585 if (!smtp_refill(*len))
586 { *len = 0; return NULL; }
587
588if ((size = smtp_inend - smtp_inptr) > *len) size = *len;
589buf = smtp_inptr;
590smtp_inptr += size;
591*len = size;
592return buf;
593}
594
584e96c6
JH
595void
596smtp_get_cache(void)
597{
9960d1e5 598#ifndef DISABLE_DKIM
584e96c6
JH
599int n = smtp_inend - smtp_inptr;
600if (n > 0)
601 dkim_exim_verify_feed(smtp_inptr, n);
584e96c6 602#endif
9960d1e5 603}
059ec3d9
PH
604
605
7e3ce68e
JH
606/* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the
607previous BDAT chunk and getting new ones when we run out. Uses the
608underlying smtp_getc or tls_getc both for that and for getting the
609(buffered) data byte. EOD signals (an expected) no further data.
610ERR signals a protocol error, and EOF a closed input stream.
611
612Called from read_bdat_smtp() in receive.c for the message body, but also
613by the headers read loop in receive_msg(); manipulates chunking_state
614to handle the BDAT command/response.
615Placed here due to the correlation with the above smtp_getc(), which it wraps,
616and also by the need to do smtp command/response handling.
617
bd8fbe36 618Arguments: lim (ignored)
7e3ce68e
JH
619Returns: the next character or ERR, EOD or EOF
620*/
621
622int
bd8fbe36 623bdat_getc(unsigned lim)
7e3ce68e
JH
624{
625uschar * user_msg = NULL;
626uschar * log_msg;
627
628for(;;)
629 {
79de4f37 630#ifndef DISABLE_DKIM
64b67b65 631 unsigned dkim_save;
79de4f37
JH
632#endif
633
bd8fbe36
JH
634 if (chunking_data_left > 0)
635 return lwr_receive_getc(chunking_data_left--);
7e3ce68e
JH
636
637 receive_getc = lwr_receive_getc;
0d81dabc 638 receive_getbuf = lwr_receive_getbuf;
7e3ce68e 639 receive_ungetc = lwr_receive_ungetc;
bd8fbe36 640#ifndef DISABLE_DKIM
79de4f37 641 dkim_save = dkim_collect_input;
64b67b65 642 dkim_collect_input = 0;
bd8fbe36 643#endif
7e3ce68e 644
f4630439
JH
645 /* Unless PIPELINING was offered, there should be no next command
646 until after we ack that chunk */
647
8768d548 648 if (!f.smtp_in_pipelining_advertised && !check_sync())
f4630439 649 {
40525d07
JH
650 unsigned n = smtp_inend - smtp_inptr;
651 if (n > 32) n = 32;
652
f4630439
JH
653 incomplete_transaction_log(US"sync failure");
654 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error "
655 "(next input sent too soon: pipelining was not advertised): "
9e0ed81f 656 "rejected \"%s\" %s next input=\"%s\"%s",
f4630439 657 smtp_cmd_buffer, host_and_ident(TRUE),
9e0ed81f
JH
658 string_printing(string_copyn(smtp_inptr, n)),
659 smtp_inend - smtp_inptr > n ? "..." : "");
660 (void) synprot_error(L_smtp_protocol_error, 554, NULL,
661 US"SMTP synchronization error");
f4630439
JH
662 goto repeat_until_rset;
663 }
664
7e3ce68e
JH
665 /* If not the last, ack the received chunk. The last response is delayed
666 until after the data ACL decides on it */
7e3ce68e
JH
667
668 if (chunking_state == CHUNKING_LAST)
584e96c6
JH
669 {
670#ifndef DISABLE_DKIM
e983e85a 671 dkim_exim_verify_feed(NULL, 0); /* notify EOD */
584e96c6 672#endif
7e3ce68e 673 return EOD;
584e96c6 674 }
7e3ce68e 675
925ac8e4 676 smtp_printf("250 %u byte chunk received\r\n", FALSE, chunking_datasize);
bd8fbe36
JH
677 chunking_state = CHUNKING_OFFERED;
678 DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
7e3ce68e
JH
679
680 /* Expect another BDAT cmd from input. RFC 3030 says nothing about
681 QUIT, RSET or NOOP but handling them seems obvious */
682
683next_cmd:
bd8fbe36 684 switch(smtp_read_command(TRUE, 1))
7e3ce68e
JH
685 {
686 default:
687 (void) synprot_error(L_smtp_protocol_error, 503, NULL,
688 US"only BDAT permissible after non-LAST BDAT");
689
690 repeat_until_rset:
bd8fbe36 691 switch(smtp_read_command(TRUE, 1))
7e3ce68e
JH
692 {
693 case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */
694 case EOF_CMD: return EOF;
695 case RSET_CMD: smtp_rset_handler(); return ERR;
696 default: if (synprot_error(L_smtp_protocol_error, 503, NULL,
697 US"only RSET accepted now") > 0)
698 return EOF;
699 goto repeat_until_rset;
700 }
701
702 case QUIT_CMD:
703 smtp_quit_handler(&user_msg, &log_msg);
704 /*FALLTHROUGH*/
705 case EOF_CMD:
706 return EOF;
707
708 case RSET_CMD:
709 smtp_rset_handler();
710 return ERR;
711
712 case NOOP_CMD:
713 HAD(SCH_NOOP);
925ac8e4 714 smtp_printf("250 OK\r\n", FALSE);
7e3ce68e
JH
715 goto next_cmd;
716
717 case BDAT_CMD:
718 {
719 int n;
720
721 if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1)
722 {
723 (void) synprot_error(L_smtp_protocol_error, 501, NULL,
724 US"missing size for BDAT command");
725 return ERR;
726 }
727 chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0
728 ? CHUNKING_LAST : CHUNKING_ACTIVE;
729 chunking_data_left = chunking_datasize;
bd8fbe36
JH
730 DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n",
731 (int)chunking_state, chunking_data_left);
7e3ce68e
JH
732
733 if (chunking_datasize == 0)
734 if (chunking_state == CHUNKING_LAST)
735 return EOD;
736 else
737 {
738 (void) synprot_error(L_smtp_protocol_error, 504, NULL,
739 US"zero size for BDAT command");
740 goto repeat_until_rset;
741 }
742
743 receive_getc = bdat_getc;
8b77d27a 744 receive_getbuf = bdat_getbuf; /* r~getbuf is never actually used */
7e3ce68e 745 receive_ungetc = bdat_ungetc;
bd8fbe36 746#ifndef DISABLE_DKIM
79de4f37 747 dkim_collect_input = dkim_save;
bd8fbe36 748#endif
7e3ce68e
JH
749 break; /* to top of main loop */
750 }
751 }
752 }
753}
754
0d81dabc
JH
755uschar *
756bdat_getbuf(unsigned * len)
757{
758uschar * buf;
759
760if (chunking_data_left <= 0)
761 { *len = 0; return NULL; }
762
763if (*len > chunking_data_left) *len = chunking_data_left;
764buf = lwr_receive_getbuf(len); /* Either smtp_getbuf or tls_getbuf */
765chunking_data_left -= *len;
766return buf;
767}
768
1ebe15c3 769void
45bd315d
JH
770bdat_flush_data(void)
771{
e99a3a6c 772while (chunking_data_left)
db57e575 773 {
e99a3a6c 774 unsigned n = chunking_data_left;
8b77d27a 775 if (!bdat_getbuf(&n)) break;
db57e575 776 }
45bd315d
JH
777
778receive_getc = lwr_receive_getc;
0d81dabc 779receive_getbuf = lwr_receive_getbuf;
45bd315d
JH
780receive_ungetc = lwr_receive_ungetc;
781
782if (chunking_state != CHUNKING_LAST)
bd8fbe36 783 {
45bd315d 784 chunking_state = CHUNKING_OFFERED;
bd8fbe36
JH
785 DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state);
786 }
45bd315d
JH
787}
788
7e3ce68e
JH
789
790
791
059ec3d9
PH
792/*************************************************
793* SMTP version of ungetc() *
794*************************************************/
795
796/* Puts a character back in the input buffer. Only ever
797called once.
798
799Arguments:
800 ch the character
801
802Returns: the character
803*/
804
805int
806smtp_ungetc(int ch)
807{
7e3ce68e 808*--smtp_inptr = ch;
059ec3d9
PH
809return ch;
810}
811
812
7e3ce68e
JH
813int
814bdat_ungetc(int ch)
815{
816chunking_data_left++;
817return lwr_receive_ungetc(ch);
818}
819
059ec3d9
PH
820
821
822/*************************************************
823* SMTP version of feof() *
824*************************************************/
825
826/* Tests for a previous EOF
827
828Arguments: none
829Returns: non-zero if the eof flag is set
830*/
831
832int
833smtp_feof(void)
834{
835return smtp_had_eof;
836}
837
838
839
840
841/*************************************************
842* SMTP version of ferror() *
843*************************************************/
844
845/* Tests for a previous read error, and returns with errno
846restored to what it was when the error was detected.
847
848Arguments: none
849Returns: non-zero if the error flag is set
850*/
851
852int
853smtp_ferror(void)
854{
855errno = smtp_had_error;
856return smtp_had_error;
857}
858
859
860
58eb016e
PH
861/*************************************************
862* Test for characters in the SMTP buffer *
863*************************************************/
864
865/* Used at the end of a message
866
867Arguments: none
868Returns: TRUE/FALSE
869*/
870
871BOOL
872smtp_buffered(void)
873{
874return smtp_inptr < smtp_inend;
875}
876
877
059ec3d9
PH
878
879/*************************************************
880* Write formatted string to SMTP channel *
881*************************************************/
882
883/* This is a separate function so that we don't have to repeat everything for
884TLS support or debugging. It is global so that the daemon and the
885authentication functions can use it. It does not return any error indication,
886because major problems such as dropped connections won't show up till an output
887flush for non-TLS connections. The smtp_fflush() function is available for
888checking that: for convenience, TLS output errors are remembered here so that
889they are also picked up later by smtp_fflush().
890
891Arguments:
892 format format string
925ac8e4 893 more further data expected
059ec3d9
PH
894 ... optional arguments
895
896Returns: nothing
897*/
898
899void
925ac8e4 900smtp_printf(const char *format, BOOL more, ...)
059ec3d9
PH
901{
902va_list ap;
903
925ac8e4
JH
904va_start(ap, more);
905smtp_vprintf(format, more, ap);
ce552449
NM
906va_end(ap);
907}
908
909/* This is split off so that verify.c:respond_printf() can, in effect, call
910smtp_printf(), bearing in mind that in C a vararg function can't directly
fb08281f 911call another vararg function, only a function which accepts a va_list. */
ce552449
NM
912
913void
925ac8e4 914smtp_vprintf(const char *format, BOOL more, va_list ap)
ce552449 915{
fb08281f
DW
916BOOL yield;
917
918yield = string_vformat(big_buffer, big_buffer_size, format, ap);
ce552449 919
059ec3d9
PH
920DEBUG(D_receive)
921 {
fb08281f
DW
922 void *reset_point = store_get(0);
923 uschar *msg_copy, *cr, *end;
924 msg_copy = string_copy(big_buffer);
925 end = msg_copy + Ustrlen(msg_copy);
926 while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
927 memmove(cr, cr + 1, (end--) - cr);
928 debug_printf("SMTP>> %s", msg_copy);
929 store_reset(reset_point);
059ec3d9
PH
930 }
931
fb08281f 932if (!yield)
2679d413
PH
933 {
934 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
935 smtp_closedown(US"Unexpected error");
9bfb7e1b 936 exim_exit(EXIT_FAILURE, NULL);
2679d413 937 }
2679d413
PH
938
939/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
940have had the same. Note: this code is also present in smtp_respond(). It would
941be tidier to have it only in one place, but when it was added, it was easier to
942do it that way, so as not to have to mess with the code for the RCPT command,
943which sometimes uses smtp_printf() and sometimes smtp_respond(). */
944
88752192 945if (fl.rcpt_in_progress)
2679d413
PH
946 {
947 if (rcpt_smtp_response == NULL)
948 rcpt_smtp_response = string_copy(big_buffer);
88752192 949 else if (fl.rcpt_smtp_response_same &&
2679d413 950 Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
88752192
JH
951 fl.rcpt_smtp_response_same = FALSE;
952 fl.rcpt_in_progress = FALSE;
2679d413 953 }
059ec3d9 954
2679d413 955/* Now write the string */
059ec3d9
PH
956
957#ifdef SUPPORT_TLS
74f1a423 958if (tls_in.active.sock >= 0)
059ec3d9 959 {
74f1a423 960 if (tls_write(NULL, big_buffer, Ustrlen(big_buffer), more) < 0)
817d9f57 961 smtp_write_error = -1;
059ec3d9
PH
962 }
963else
964#endif
965
2679d413 966if (fprintf(smtp_out, "%s", big_buffer) < 0) smtp_write_error = -1;
059ec3d9
PH
967}
968
969
970
971/*************************************************
972* Flush SMTP out and check for error *
973*************************************************/
974
975/* This function isn't currently used within Exim (it detects errors when it
976tries to read the next SMTP input), but is available for use in local_scan().
977For non-TLS connections, it flushes the output and checks for errors. For
978TLS-connections, it checks for a previously-detected TLS write error.
979
980Arguments: none
981Returns: 0 for no error; -1 after an error
982*/
983
984int
985smtp_fflush(void)
986{
74f1a423 987if (tls_in.active.sock < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
059ec3d9
PH
988return smtp_write_error;
989}
990
991
992
993/*************************************************
994* SMTP command read timeout *
995*************************************************/
996
997/* Signal handler for timing out incoming SMTP commands. This attempts to
998finish off tidily.
999
1000Argument: signal number (SIGALRM)
1001Returns: nothing
1002*/
1003
1004static void
1005command_timeout_handler(int sig)
1006{
9723f966 1007had_command_timeout = sig;
059ec3d9
PH
1008}
1009
1010
1011
1012/*************************************************
1013* SIGTERM received *
1014*************************************************/
1015
1016/* Signal handler for handling SIGTERM. Again, try to finish tidily.
1017
1018Argument: signal number (SIGTERM)
1019Returns: nothing
1020*/
1021
1022static void
1023command_sigterm_handler(int sig)
1024{
9723f966 1025had_command_sigterm = sig;
059ec3d9
PH
1026}
1027
1028
1029
a14e5636 1030
cee5f132 1031#ifdef SUPPORT_PROXY
a3c86431 1032/*************************************************
a3bddaa8
TL
1033* Restore socket timeout to previous value *
1034*************************************************/
1035/* If the previous value was successfully retrieved, restore
1036it before returning control to the non-proxy routines
1037
1038Arguments: fd - File descriptor for input
1039 get_ok - Successfully retrieved previous values
1040 tvtmp - Time struct with previous values
1041 vslen - Length of time struct
1042Returns: none
1043*/
1044static void
f267271d 1045restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen)
a3bddaa8
TL
1046{
1047if (get_ok == 0)
f267271d 1048 (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen);
a3bddaa8
TL
1049}
1050
1051/*************************************************
a3c86431
TL
1052* Check if host is required proxy host *
1053*************************************************/
1054/* The function determines if inbound host will be a regular smtp host
1811cb4c
JH
1055or if it is configured that it must use Proxy Protocol. A local
1056connection cannot.
a3c86431
TL
1057
1058Arguments: none
1059Returns: bool
1060*/
1061
1062static BOOL
1063check_proxy_protocol_host()
1064{
1065int rc;
a3c86431 1066
1811cb4c
JH
1067if ( sender_host_address
1068 && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL,
1069 sender_host_address, NULL)) == OK)
a3c86431
TL
1070 {
1071 DEBUG(D_receive)
1072 debug_printf("Detected proxy protocol configured host\n");
1073 proxy_session = TRUE;
1074 }
1075return proxy_session;
1076}
1077
1078
1079/*************************************************
3f251b3c
PP
1080* Read data until newline or end of buffer *
1081*************************************************/
1082/* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't
1083read an entire buffer and assume there will be nothing past a proxy protocol
1084header. Our approach normally is to use stdio, but again that relies upon
1085"STARTTLS\r\n" and a server response before the client starts TLS handshake, or
1086reading _nothing_ before client TLS handshake. So we don't want to use the
1087usual buffering reads which may read enough to block TLS starting.
1088
1089So unfortunately we're down to "read one byte at a time, with a syscall each,
1090and expect a little overhead", for all proxy-opened connections which are v1,
1091just to handle the TLS-on-connect case. Since SSL functions wrap the
1092underlying fd, we can't assume that we can feed them any already-read content.
1093
1094We need to know where to read to, the max capacity, and we'll read until we
1095get a CR and one more character. Let the caller scream if it's CR+!LF.
1096
1097Return the amount read.
1098*/
1099
1100static int
da88acae 1101swallow_until_crlf(int fd, uschar *base, int already, int capacity)
3f251b3c 1102{
2c0f3ea1
JH
1103uschar *to = base + already;
1104uschar *cr;
1105int have = 0;
1106int ret;
1107int last = 0;
1108
1109/* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read
1110up through the \r; for the _normal_ case, we haven't yet seen the \r. */
da88acae 1111
2c0f3ea1
JH
1112cr = memchr(base, '\r', already);
1113if (cr != NULL)
1114 {
1115 if ((cr - base) < already - 1)
da88acae 1116 {
2c0f3ea1
JH
1117 /* \r and presumed \n already within what we have; probably not
1118 actually proxy protocol, but abort cleanly. */
1119 return 0;
da88acae 1120 }
2c0f3ea1
JH
1121 /* \r is last character read, just need one more. */
1122 last = 1;
1123 }
1124
1125while (capacity > 0)
1126 {
1127 do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR);
1128 if (ret == -1)
1129 return -1;
1130 have++;
1131 if (last)
1132 return have;
1133 if (*to == '\r')
1134 last = 1;
1135 capacity--;
1136 to++;
1137 }
1138
1139/* reached end without having room for a final newline, abort */
1140errno = EOVERFLOW;
1141return -1;
3f251b3c
PP
1142}
1143
1144/*************************************************
a3c86431
TL
1145* Setup host for proxy protocol *
1146*************************************************/
1147/* The function configures the connection based on a header from the
1148inbound host to use Proxy Protocol. The specification is very exact
1149so exit with an error if do not find the exact required pieces. This
1150includes an incorrect number of spaces separating args.
1151
1152Arguments: none
f267271d 1153Returns: Boolean success
a3c86431
TL
1154*/
1155
1811cb4c 1156static void
a3c86431
TL
1157setup_proxy_protocol_host()
1158{
1159union {
1160 struct {
1161 uschar line[108];
1162 } v1;
1163 struct {
1164 uschar sig[12];
36719342
TL
1165 uint8_t ver_cmd;
1166 uint8_t fam;
1167 uint16_t len;
a3c86431
TL
1168 union {
1169 struct { /* TCP/UDP over IPv4, len = 12 */
1170 uint32_t src_addr;
1171 uint32_t dst_addr;
1172 uint16_t src_port;
1173 uint16_t dst_port;
1174 } ip4;
1175 struct { /* TCP/UDP over IPv6, len = 36 */
1176 uint8_t src_addr[16];
1177 uint8_t dst_addr[16];
1178 uint16_t src_port;
1179 uint16_t dst_port;
1180 } ip6;
1181 struct { /* AF_UNIX sockets, len = 216 */
1182 uschar src_addr[108];
1183 uschar dst_addr[108];
1184 } unx;
1185 } addr;
1186 } v2;
1187} hdr;
1188
eb57651e
TL
1189/* Temp variables used in PPv2 address:port parsing */
1190uint16_t tmpport;
1191char tmpip[INET_ADDRSTRLEN];
1192struct sockaddr_in tmpaddr;
1193char tmpip6[INET6_ADDRSTRLEN];
1194struct sockaddr_in6 tmpaddr6;
1195
da88acae
PP
1196/* We can't read "all data until end" because while SMTP is
1197server-speaks-first, the TLS handshake is client-speaks-first, so for
1198TLS-on-connect ports the proxy protocol header will usually be immediately
1199followed by a TLS handshake, and with N TLS libraries, we can't reliably
1200reinject data for reading by those. So instead we first read "enough to be
1201safely read within the header, and figure out how much more to read".
1202For v1 we will later read to the end-of-line, for v2 we will read based upon
1203the stated length.
1204
1205The v2 sig is 12 octets, and another 4 gets us the length, so we know how much
1206data is needed total. For v1, where the line looks like:
1207PROXY TCPn L3src L3dest SrcPort DestPort \r\n
1208
1209However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets.
1210We seem to support that. So, if we read 14 octets then we can tell if we're
1211v2 or v1. If we're v1, we can continue reading as normal.
1212
1213If we're v2, we can't slurp up the entire header. We need the length in the
121415th & 16th octets, then to read everything after that.
1215
1216So to safely handle v1 and v2, with client-sent-first supported correctly,
1217we have to do a minimum of 3 read calls, not 1. Eww.
1218*/
1219
1220#define PROXY_INITIAL_READ 14
1221#define PROXY_V2_HEADER_SIZE 16
1222#if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE
1223# error Code bug in sizes of data to read for proxy usage
1224#endif
1225
eb57651e 1226int get_ok = 0;
f267271d
JH
1227int size, ret;
1228int fd = fileno(smtp_in);
36719342 1229const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
9e7e0f6a 1230uschar * iptype; /* To display debug info */
a3c86431 1231struct timeval tv;
a3bddaa8 1232struct timeval tvtmp;
f267271d 1233socklen_t vslen = sizeof(struct timeval);
1811cb4c 1234BOOL yield = FALSE;
a3c86431 1235
a3bddaa8 1236/* Save current socket timeout values */
f267271d 1237get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen);
a3bddaa8 1238
a3c86431
TL
1239/* Proxy Protocol host must send header within a short time
1240(default 3 seconds) or it's considered invalid */
1241tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC;
1242tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC;
f267271d 1243if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0)
1811cb4c 1244 goto bad;
a3bddaa8 1245
a3c86431
TL
1246do
1247 {
eb57651e 1248 /* The inbound host was declared to be a Proxy Protocol host, so
2c0f3ea1
JH
1249 don't do a PEEK into the data, actually slurp up enough to be
1250 "safe". Can't take it all because TLS-on-connect clients follow
1251 immediately with TLS handshake. */
3f251b3c 1252 ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0);
a3c86431
TL
1253 }
1254 while (ret == -1 && errno == EINTR);
1255
1256if (ret == -1)
f267271d 1257 goto proxyfail;
a3c86431 1258
da88acae
PP
1259/* For v2, handle reading the length, and then the rest. */
1260if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0))
a3c86431 1261 {
da88acae
PP
1262 int retmore;
1263 uint8_t ver;
1264
1265 /* First get the length fields. */
1266 do
1267 {
1268 retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0);
1269 } while (retmore == -1 && errno == EINTR);
1270 if (retmore == -1)
3f251b3c 1271 goto proxyfail;
da88acae 1272 ret += retmore;
3f251b3c
PP
1273
1274 ver = (hdr.v2.ver_cmd & 0xf0) >> 4;
36719342
TL
1275
1276 /* May 2014: haproxy combined the version and command into one byte to
2c0f3ea1
JH
1277 allow two full bytes for the length field in order to proxy SSL
1278 connections. SSL Proxy is not supported in this version of Exim, but
1279 must still separate values here. */
36719342
TL
1280
1281 if (ver != 0x02)
1282 {
1283 DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver);
1284 goto proxyfail;
1285 }
da88acae 1286
36719342 1287 /* The v2 header will always be 16 bytes per the spec. */
5d036699 1288 size = 16 + ntohs(hdr.v2.len);
da88acae
PP
1289 DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n",
1290 size, (int)sizeof(hdr));
1291
1292 /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total
1293 amount that we need. Double-check that the size is not unreasonable, then
1294 get the rest. */
1295 if (size > sizeof(hdr))
a3c86431 1296 {
da88acae 1297 DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n");
a3c86431
TL
1298 goto proxyfail;
1299 }
da88acae
PP
1300
1301 do
1302 {
1303 do
1304 {
1305 retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0);
1306 } while (retmore == -1 && errno == EINTR);
1307 if (retmore == -1)
1308 goto proxyfail;
1309 ret += retmore;
1310 DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size);
1311 } while (ret < size);
1312
1313 } /* end scope for getting rest of data for v2 */
1314
1315/* At this point: if PROXYv2, we've read the exact size required for all data;
1316if PROXYv1 then we've read "less than required for any valid line" and should
1317read the rest". */
1318
1319if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0)
1320 {
1321 uint8_t cmd = (hdr.v2.ver_cmd & 0x0f);
1322
36719342 1323 switch (cmd)
a3c86431
TL
1324 {
1325 case 0x01: /* PROXY command */
1326 switch (hdr.v2.fam)
1327 {
eb57651e
TL
1328 case 0x11: /* TCPv4 address type */
1329 iptype = US"IPv4";
1330 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr;
5d036699
JH
1331 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1332 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1333 {
1334 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1335 goto proxyfail;
eb57651e 1336 }
e6d2a989 1337 proxy_local_address = sender_host_address;
eb57651e
TL
1338 sender_host_address = string_copy(US tmpip);
1339 tmpport = ntohs(hdr.v2.addr.ip4.src_port);
e6d2a989 1340 proxy_local_port = sender_host_port;
eb57651e
TL
1341 sender_host_port = tmpport;
1342 /* Save dest ip/port */
1343 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr;
5d036699
JH
1344 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1345 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1346 {
1347 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1348 goto proxyfail;
eb57651e 1349 }
7a2fa0bc 1350 proxy_external_address = string_copy(US tmpip);
eb57651e 1351 tmpport = ntohs(hdr.v2.addr.ip4.dst_port);
7a2fa0bc 1352 proxy_external_port = tmpport;
a3c86431 1353 goto done;
eb57651e
TL
1354 case 0x21: /* TCPv6 address type */
1355 iptype = US"IPv6";
1356 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16);
5d036699
JH
1357 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1358 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1359 {
1360 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1361 goto proxyfail;
eb57651e 1362 }
e6d2a989 1363 proxy_local_address = sender_host_address;
eb57651e
TL
1364 sender_host_address = string_copy(US tmpip6);
1365 tmpport = ntohs(hdr.v2.addr.ip6.src_port);
e6d2a989 1366 proxy_local_port = sender_host_port;
eb57651e
TL
1367 sender_host_port = tmpport;
1368 /* Save dest ip/port */
1369 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16);
5d036699
JH
1370 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1371 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1372 {
1373 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1374 goto proxyfail;
eb57651e 1375 }
7a2fa0bc 1376 proxy_external_address = string_copy(US tmpip6);
eb57651e 1377 tmpport = ntohs(hdr.v2.addr.ip6.dst_port);
7a2fa0bc 1378 proxy_external_port = tmpport;
a3c86431 1379 goto done;
eb57651e
TL
1380 default:
1381 DEBUG(D_receive)
1382 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
1383 hdr.v2.fam);
1384 goto proxyfail;
a3c86431
TL
1385 }
1386 /* Unsupported protocol, keep local connection address */
1387 break;
1388 case 0x00: /* LOCAL command */
1389 /* Keep local connection address for LOCAL */
9e7e0f6a 1390 iptype = US"local";
a3c86431
TL
1391 break;
1392 default:
eb57651e 1393 DEBUG(D_receive)
36719342 1394 debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd);
a3c86431
TL
1395 goto proxyfail;
1396 }
1397 }
5d036699 1398else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0)
a3c86431 1399 {
3f251b3c
PP
1400 uschar *p;
1401 uschar *end;
a3c86431
TL
1402 uschar *sp; /* Utility variables follow */
1403 int tmp_port;
3f251b3c 1404 int r2;
a3c86431
TL
1405 char *endc;
1406
3f251b3c 1407 /* get the rest of the line */
da88acae 1408 r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
3f251b3c
PP
1409 if (r2 == -1)
1410 goto proxyfail;
1411 ret += r2;
1412
1413 p = string_copy(hdr.v1.line);
1414 end = memchr(p, '\r', ret - 1);
1415
da88acae 1416 if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n')
a3c86431
TL
1417 {
1418 DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n");
1419 goto proxyfail;
1420 }
1421 *end = '\0'; /* Terminate the string */
a5d4db40 1422 size = end + 2 - p; /* Skip header + CRLF */
a3c86431 1423 DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n");
3f251b3c 1424 DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size);
a3c86431 1425 /* Step through the string looking for the required fields. Ensure
2c0f3ea1 1426 strict adherence to required formatting, exit for any error. */
a3c86431
TL
1427 p += 5;
1428 if (!isspace(*(p++)))
1429 {
1430 DEBUG(D_receive) debug_printf("Missing space after PROXY command\n");
1431 goto proxyfail;
1432 }
1433 if (!Ustrncmp(p, CCS"TCP4", 4))
1434 iptype = US"IPv4";
1435 else if (!Ustrncmp(p,CCS"TCP6", 4))
1436 iptype = US"IPv6";
1437 else if (!Ustrncmp(p,CCS"UNKNOWN", 7))
1438 {
1439 iptype = US"Unknown";
1440 goto done;
1441 }
1442 else
1443 {
1444 DEBUG(D_receive) debug_printf("Invalid TCP type\n");
1445 goto proxyfail;
1446 }
1447
1448 p += Ustrlen(iptype);
1449 if (!isspace(*(p++)))
1450 {
1451 DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n");
1452 goto proxyfail;
1453 }
1454 /* Find the end of the arg */
1455 if ((sp = Ustrchr(p, ' ')) == NULL)
1456 {
1457 DEBUG(D_receive)
1458 debug_printf("Did not find proxied src %s\n", iptype);
1459 goto proxyfail;
1460 }
1461 *sp = '\0';
5d036699 1462 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1463 {
1464 DEBUG(D_receive)
1465 debug_printf("Proxied src arg is not an %s address\n", iptype);
1466 goto proxyfail;
1467 }
e6d2a989 1468 proxy_local_address = sender_host_address;
a3c86431
TL
1469 sender_host_address = p;
1470 p = sp + 1;
1471 if ((sp = Ustrchr(p, ' ')) == NULL)
1472 {
1473 DEBUG(D_receive)
1474 debug_printf("Did not find proxy dest %s\n", iptype);
1475 goto proxyfail;
1476 }
1477 *sp = '\0';
5d036699 1478 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1479 {
1480 DEBUG(D_receive)
1481 debug_printf("Proxy dest arg is not an %s address\n", iptype);
1482 goto proxyfail;
1483 }
7a2fa0bc 1484 proxy_external_address = p;
a3c86431
TL
1485 p = sp + 1;
1486 if ((sp = Ustrchr(p, ' ')) == NULL)
1487 {
1488 DEBUG(D_receive) debug_printf("Did not find proxied src port\n");
1489 goto proxyfail;
1490 }
1491 *sp = '\0';
5d036699 1492 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1493 if (*endc || tmp_port == 0)
1494 {
1495 DEBUG(D_receive)
1496 debug_printf("Proxied src port '%s' not an integer\n", p);
1497 goto proxyfail;
1498 }
e6d2a989 1499 proxy_local_port = sender_host_port;
a3c86431
TL
1500 sender_host_port = tmp_port;
1501 p = sp + 1;
1502 if ((sp = Ustrchr(p, '\0')) == NULL)
1503 {
1504 DEBUG(D_receive) debug_printf("Did not find proxy dest port\n");
1505 goto proxyfail;
1506 }
5d036699 1507 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1508 if (*endc || tmp_port == 0)
1509 {
1510 DEBUG(D_receive)
1511 debug_printf("Proxy dest port '%s' not an integer\n", p);
1512 goto proxyfail;
1513 }
7a2fa0bc 1514 proxy_external_port = tmp_port;
a3c86431 1515 /* Already checked for /r /n above. Good V1 header received. */
a3c86431
TL
1516 }
1517else
1518 {
1519 /* Wrong protocol */
eb57651e 1520 DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n");
da88acae 1521 (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
a3c86431
TL
1522 goto proxyfail;
1523 }
1524
1811cb4c
JH
1525done:
1526 DEBUG(D_receive)
1527 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype);
1528 yield = proxy_session;
1529
1530/* Don't flush any potential buffer contents. Any input on proxyfail
1531should cause a synchronization failure */
1532
a3c86431 1533proxyfail:
1811cb4c 1534 restore_socket_timeout(fd, get_ok, &tvtmp, vslen);
a3c86431 1535
1811cb4c
JH
1536bad:
1537 if (yield)
1538 {
1539 sender_host_name = NULL;
1540 (void) host_name_lookup();
1541 host_build_sender_fullhost();
1542 }
1543 else
1544 {
8768d548 1545 f.proxy_session_failed = TRUE;
1811cb4c
JH
1546 DEBUG(D_receive)
1547 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
1548 }
1549
1550return;
a3c86431
TL
1551}
1552#endif
1553
059ec3d9
PH
1554/*************************************************
1555* Read one command line *
1556*************************************************/
1557
1558/* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
1559There are sites that don't do this, and in any case internal SMTP probably
1560should check only for LF. Consequently, we check here for LF only. The line
1561ends up with [CR]LF removed from its end. If we get an overlong line, treat as
3ee512ff
PH
1562an unknown command. The command is read into the global smtp_cmd_buffer so that
1563it is available via $smtp_command.
059ec3d9
PH
1564
1565The character reading routine sets up a timeout for each block actually read
1566from the input (which may contain more than one command). We set up a special
1567signal handler that closes down the session on a timeout. Control does not
1568return when it runs.
1569
1570Arguments:
bd8fbe36
JH
1571 check_sync if TRUE, check synchronization rules if global option is TRUE
1572 buffer_lim maximum to buffer in lower layer
059ec3d9
PH
1573
1574Returns: a code identifying the command (enumerated above)
1575*/
1576
1577static int
bd8fbe36 1578smtp_read_command(BOOL check_sync, unsigned buffer_lim)
059ec3d9
PH
1579{
1580int c;
1581int ptr = 0;
1582smtp_cmd_list *p;
1583BOOL hadnull = FALSE;
1584
9723f966 1585had_command_timeout = 0;
059ec3d9
PH
1586os_non_restarting_signal(SIGALRM, command_timeout_handler);
1587
bd8fbe36 1588while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF)
059ec3d9 1589 {
bd8fbe36 1590 if (ptr >= SMTP_CMD_BUFFER_SIZE)
059ec3d9
PH
1591 {
1592 os_non_restarting_signal(SIGALRM, sigalrm_handler);
1593 return OTHER_CMD;
1594 }
1595 if (c == 0)
1596 {
1597 hadnull = TRUE;
1598 c = '?';
1599 }
3ee512ff 1600 smtp_cmd_buffer[ptr++] = c;
059ec3d9
PH
1601 }
1602
1603receive_linecount++; /* For BSMTP errors */
1604os_non_restarting_signal(SIGALRM, sigalrm_handler);
1605
1606/* If hit end of file, return pseudo EOF command. Whether we have a
1607part-line already read doesn't matter, since this is an error state. */
1608
1609if (c == EOF) return EOF_CMD;
1610
1611/* Remove any CR and white space at the end of the line, and terminate the
1612string. */
1613
3ee512ff
PH
1614while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
1615smtp_cmd_buffer[ptr] = 0;
059ec3d9 1616
3ee512ff 1617DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
059ec3d9
PH
1618
1619/* NULLs are not allowed in SMTP commands */
1620
1621if (hadnull) return BADCHAR_CMD;
1622
1623/* Scan command list and return identity, having set the data pointer
1624to the start of the actual data characters. Check for SMTP synchronization
1625if required. */
1626
1627for (p = cmd_list; p < cmd_list_end; p++)
1628 {
1811cb4c 1629#ifdef SUPPORT_PROXY
a3c86431 1630 /* Only allow QUIT command if Proxy Protocol parsing failed */
8768d548 1631 if (proxy_session && f.proxy_session_failed && p->cmd != QUIT_CMD)
1811cb4c
JH
1632 continue;
1633#endif
2f460950
JH
1634 if ( p->len
1635 && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0
1636 && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */
1637 || smtp_cmd_buffer[p->len] == 0
1638 || smtp_cmd_buffer[p->len] == ' '
1639 ) )
059ec3d9
PH
1640 {
1641 if (smtp_inptr < smtp_inend && /* Outstanding input */
1642 p->cmd < sync_cmd_limit && /* Command should sync */
1643 check_sync && /* Local flag set */
1644 smtp_enforce_sync && /* Global flag set */
1645 sender_host_address != NULL && /* Not local input */
8768d548 1646 !f.sender_host_notsocket) /* Really is a socket */
059ec3d9
PH
1647 return BADSYN_CMD;
1648
ca86f471
PH
1649 /* The variables $smtp_command and $smtp_command_argument point into the
1650 unmodified input buffer. A copy of the latter is taken for actual
1651 processing, so that it can be chopped up into separate parts if necessary,
1652 for example, when processing a MAIL command options such as SIZE that can
1653 follow the sender address. */
059ec3d9 1654
3ee512ff 1655 smtp_cmd_argument = smtp_cmd_buffer + p->len;
ca86f471
PH
1656 while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
1657 Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
1658 smtp_cmd_data = smtp_data_buffer;
059ec3d9
PH
1659
1660 /* Count non-mail commands from those hosts that are controlled in this
1661 way. The default is all hosts. We don't waste effort checking the list
1662 until we get a non-mail command, but then cache the result to save checking
1663 again. If there's a DEFER while checking the host, assume it's in the list.
1664
1665 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1666 start of each incoming message by fiddling with the value in the table. */
1667
1668 if (!p->is_mail_cmd)
1669 {
1670 if (count_nonmail == TRUE_UNSET) count_nonmail =
1671 verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL;
1672 if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail)
1673 return TOO_MANY_NONMAIL_CMD;
1674 }
1675
ca86f471
PH
1676 /* If there is data for a command that does not expect it, generate the
1677 error here. */
059ec3d9 1678
ca86f471 1679 return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
059ec3d9
PH
1680 }
1681 }
1682
cee5f132 1683#ifdef SUPPORT_PROXY
a3c86431 1684/* Only allow QUIT command if Proxy Protocol parsing failed */
8768d548 1685if (proxy_session && f.proxy_session_failed)
a3c86431
TL
1686 return PROXY_FAIL_IGNORE_CMD;
1687#endif
1688
059ec3d9
PH
1689/* Enforce synchronization for unknown commands */
1690
ecce6d9a
JH
1691if ( smtp_inptr < smtp_inend /* Outstanding input */
1692 && check_sync /* Local flag set */
1693 && smtp_enforce_sync /* Global flag set */
1694 && sender_host_address /* Not local input */
8768d548 1695 && !f.sender_host_notsocket) /* Really is a socket */
059ec3d9
PH
1696 return BADSYN_CMD;
1697
1698return OTHER_CMD;
1699}
1700
1701
1702
1703/*************************************************
1704* Forced closedown of call *
1705*************************************************/
1706
1707/* This function is called from log.c when Exim is dying because of a serious
1708disaster, and also from some other places. If an incoming non-batched SMTP
1709channel is open, it swallows the rest of the incoming message if in the DATA
1710phase, sends the reply string, and gives an error to all subsequent commands
1711except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1712smtp_in.
1713
8f128379
PH
1714Arguments:
1715 message SMTP reply string to send, excluding the code
1716
059ec3d9
PH
1717Returns: nothing
1718*/
1719
1720void
1721smtp_closedown(uschar *message)
1722{
db57e575 1723if (!smtp_in || smtp_batched_input) return;
059ec3d9 1724receive_swallow_smtp();
925ac8e4 1725smtp_printf("421 %s\r\n", FALSE, message);
059ec3d9 1726
bd8fbe36 1727for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9 1728 {
60d10ce7 1729 case EOF_CMD:
db57e575 1730 return;
059ec3d9 1731
60d10ce7 1732 case QUIT_CMD:
db57e575
JH
1733 smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
1734 mac_smtp_fflush();
1735 return;
059ec3d9 1736
60d10ce7 1737 case RSET_CMD:
db57e575
JH
1738 smtp_printf("250 Reset OK\r\n", FALSE);
1739 break;
059ec3d9 1740
60d10ce7 1741 default:
db57e575
JH
1742 smtp_printf("421 %s\r\n", FALSE, message);
1743 break;
059ec3d9
PH
1744 }
1745}
1746
1747
1748
1749
1750/*************************************************
1751* Set up connection info for logging *
1752*************************************************/
1753
1754/* This function is called when logging information about an SMTP connection.
1755It sets up appropriate source information, depending on the type of connection.
dac79d3e
PH
1756If sender_fullhost is NULL, we are at a very early stage of the connection;
1757just use the IP address.
059ec3d9
PH
1758
1759Argument: none
1760Returns: a string describing the connection
1761*/
1762
1763uschar *
1764smtp_get_connection_info(void)
1765{
f5d25c2b
JH
1766const uschar * hostname = sender_fullhost
1767 ? sender_fullhost : sender_host_address;
dac79d3e 1768
059ec3d9 1769if (host_checking)
dac79d3e 1770 return string_sprintf("SMTP connection from %s", hostname);
059ec3d9 1771
8768d548 1772if (f.sender_host_unknown || f.sender_host_notsocket)
059ec3d9
PH
1773 return string_sprintf("SMTP connection from %s", sender_ident);
1774
8768d548 1775if (f.is_inetd)
dac79d3e 1776 return string_sprintf("SMTP connection from %s (via inetd)", hostname);
059ec3d9 1777
6c6d6e48 1778if (LOGGING(incoming_interface) && interface_address != NULL)
dac79d3e 1779 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
059ec3d9
PH
1780 interface_address, interface_port);
1781
dac79d3e 1782return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1783}
1784
1785
1786
e45a1c37 1787#ifdef SUPPORT_TLS
887291d2
JH
1788/* Append TLS-related information to a log line
1789
1790Arguments:
acec9514 1791 g String under construction: allocated string to extend, or NULL
887291d2
JH
1792
1793Returns: Allocated string or NULL
1794*/
acec9514
JH
1795static gstring *
1796s_tlslog(gstring * g)
e45a1c37 1797{
acec9514
JH
1798if (LOGGING(tls_cipher) && tls_in.cipher)
1799 g = string_append(g, 2, US" X=", tls_in.cipher);
1800if (LOGGING(tls_certificate_verified) && tls_in.cipher)
1801 g = string_append(g, 2, US" CV=", tls_in.certificate_verified? "yes":"no");
1802if (LOGGING(tls_peerdn) && tls_in.peerdn)
1803 g = string_append(g, 3, US" DN=\"", string_printing(tls_in.peerdn), US"\"");
1804if (LOGGING(tls_sni) && tls_in.sni)
1805 g = string_append(g, 3, US" SNI=\"", string_printing(tls_in.sni), US"\"");
1806return g;
e45a1c37
JH
1807}
1808#endif
1809
059ec3d9 1810/*************************************************
b4ed4da0
PH
1811* Log lack of MAIL if so configured *
1812*************************************************/
1813
1814/* This function is called when an SMTP session ends. If the log selector
1815smtp_no_mail is set, write a log line giving some details of what has happened
1816in the SMTP session.
1817
1818Arguments: none
1819Returns: nothing
1820*/
1821
1822void
1823smtp_log_no_mail(void)
1824{
acec9514
JH
1825int i;
1826uschar * sep, * s;
1827gstring * g = NULL;
b4ed4da0 1828
6c6d6e48 1829if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail))
b4ed4da0
PH
1830 return;
1831
db57e575 1832if (sender_host_authenticated)
b4ed4da0 1833 {
acec9514
JH
1834 g = string_append(g, 2, US" A=", sender_host_authenticated);
1835 if (authenticated_id) g = string_append(g, 2, US":", authenticated_id);
b4ed4da0
PH
1836 }
1837
1838#ifdef SUPPORT_TLS
acec9514 1839g = s_tlslog(g);
3f0945ff 1840#endif
b4ed4da0 1841
acec9514
JH
1842sep = smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE ? US" C=..." : US" C=";
1843
b4ed4da0 1844for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
b4ed4da0
PH
1845 if (smtp_connection_had[i] != SCH_NONE)
1846 {
acec9514 1847 g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
b4ed4da0
PH
1848 sep = US",";
1849 }
b4ed4da0
PH
1850
1851for (i = 0; i < smtp_ch_index; i++)
1852 {
acec9514 1853 g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
b4ed4da0
PH
1854 sep = US",";
1855 }
1856
acec9514
JH
1857if (!(s = string_from_gstring(g))) s = US"";
1858
a2673768 1859log_write(0, LOG_MAIN, "no MAIL in %sSMTP connection from %s D=%s%s",
ee8b8090 1860 f.tcp_in_fastopen ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO " : US"",
0f1a8658 1861 host_and_ident(FALSE), string_timesince(&smtp_connection_start), s);
b4ed4da0
PH
1862}
1863
1864
a09f2942
JH
1865/* Return list of recent smtp commands */
1866
1867uschar *
1868smtp_cmd_hist(void)
1869{
acec9514
JH
1870int i;
1871gstring * list = NULL;
1872uschar * s;
a09f2942
JH
1873
1874for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
1875 if (smtp_connection_had[i] != SCH_NONE)
acec9514
JH
1876 list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
1877
a09f2942 1878for (i = 0; i < smtp_ch_index; i++)
acec9514
JH
1879 list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
1880
1881s = string_from_gstring(list);
1882return s ? s : US"";
a09f2942
JH
1883}
1884
1885
1886
b4ed4da0
PH
1887
1888/*************************************************
059ec3d9
PH
1889* Check HELO line and set sender_helo_name *
1890*************************************************/
1891
1892/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1893the domain name of the sending host, or an ip literal in square brackets. The
4c04137d 1894argument is placed in sender_helo_name, which is in malloc store, because it
059ec3d9
PH
1895must persist over multiple incoming messages. If helo_accept_junk is set, this
1896host is permitted to send any old junk (needed for some broken hosts).
1897Otherwise, helo_allow_chars can be used for rogue characters in general
1898(typically people want to let in underscores).
1899
1900Argument:
1901 s the data portion of the line (already past any white space)
1902
1903Returns: TRUE or FALSE
1904*/
1905
1906static BOOL
1907check_helo(uschar *s)
1908{
1909uschar *start = s;
1910uschar *end = s + Ustrlen(s);
88752192 1911BOOL yield = fl.helo_accept_junk;
059ec3d9
PH
1912
1913/* Discard any previous helo name */
1914
2d0dc929 1915if (sender_helo_name)
059ec3d9
PH
1916 {
1917 store_free(sender_helo_name);
1918 sender_helo_name = NULL;
1919 }
1920
1921/* Skip tests if junk is permitted. */
1922
1923if (!yield)
db57e575 1924
059ec3d9
PH
1925 /* Allow the new standard form for IPv6 address literals, namely,
1926 [IPv6:....], and because someone is bound to use it, allow an equivalent
1927 IPv4 form. Allow plain addresses as well. */
1928
1929 if (*s == '[')
1930 {
1931 if (end[-1] == ']')
1932 {
1933 end[-1] = 0;
1934 if (strncmpic(s, US"[IPv6:", 6) == 0)
1935 yield = (string_is_ip_address(s+6, NULL) == 6);
1936 else if (strncmpic(s, US"[IPv4:", 6) == 0)
1937 yield = (string_is_ip_address(s+6, NULL) == 4);
1938 else
1939 yield = (string_is_ip_address(s+1, NULL) != 0);
1940 end[-1] = ']';
1941 }
1942 }
1943
1944 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1945 that have been configured (usually underscore - sigh). */
1946
db57e575
JH
1947 else if (*s)
1948 for (yield = TRUE; *s; s++)
059ec3d9
PH
1949 if (!isalnum(*s) && *s != '.' && *s != '-' &&
1950 Ustrchr(helo_allow_chars, *s) == NULL)
1951 {
1952 yield = FALSE;
1953 break;
1954 }
059ec3d9
PH
1955
1956/* Save argument if OK */
1957
1958if (yield) sender_helo_name = string_copy_malloc(start);
1959return yield;
1960}
1961
1962
1963
1964
1965
1966/*************************************************
1967* Extract SMTP command option *
1968*************************************************/
1969
ca86f471 1970/* This function picks the next option setting off the end of smtp_cmd_data. It
059ec3d9
PH
1971is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1972things that can appear there.
1973
1974Arguments:
1975 name point this at the name
1976 value point this at the data string
1977
1978Returns: TRUE if found an option
1979*/
1980
1981static BOOL
1982extract_option(uschar **name, uschar **value)
1983{
1984uschar *n;
ca86f471 1985uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
059ec3d9
PH
1986while (isspace(*v)) v--;
1987v[1] = 0;
d7a2c833
JH
1988while (v > smtp_cmd_data && *v != '=' && !isspace(*v))
1989 {
1990 /* Take care to not stop at a space embedded in a quoted local-part */
1991
1992 if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1);
1993 v--;
1994 }
059ec3d9
PH
1995
1996n = v;
fd98a5c6 1997if (*v == '=')
a2673768 1998 {
fd98a5c6
JH
1999 while(isalpha(n[-1])) n--;
2000 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
2001 if (!isspace(n[-1])) return FALSE;
2002 n[-1] = 0;
a2673768 2003 }
fd98a5c6 2004else
a2673768 2005 {
fd98a5c6
JH
2006 n++;
2007 if (v == smtp_cmd_data) return FALSE;
a2673768 2008 }
059ec3d9 2009*v++ = 0;
fd98a5c6 2010*name = n;
059ec3d9
PH
2011*value = v;
2012return TRUE;
2013}
2014
2015
2016
2017
2018
059ec3d9
PH
2019/*************************************************
2020* Reset for new message *
2021*************************************************/
2022
2023/* This function is called whenever the SMTP session is reset from
e04bfa34 2024within either of the setup functions; also from the daemon loop.
059ec3d9
PH
2025
2026Argument: the stacking pool storage reset point
2027Returns: nothing
2028*/
2029
e04bfa34 2030void
059ec3d9
PH
2031smtp_reset(void *reset_point)
2032{
059ec3d9
PH
2033recipients_list = NULL;
2034rcpt_count = rcpt_defer_count = rcpt_fail_count =
2035 raw_recipients_count = recipients_count = recipients_list_max = 0;
2e0c1448 2036message_linecount = 0;
059ec3d9 2037message_size = -1;
71fafd95 2038acl_added_headers = NULL;
e7568d51 2039acl_removed_headers = NULL;
8768d548 2040f.queue_only_policy = FALSE;
2679d413 2041rcpt_smtp_response = NULL;
88752192
JH
2042fl.rcpt_smtp_response_same = TRUE;
2043fl.rcpt_in_progress = FALSE;
8768d548 2044f.deliver_freeze = FALSE; /* Can be set by ACL */
6a3f1455 2045freeze_tell = freeze_tell_config; /* Can be set by ACL */
29aba418 2046fake_response = OK; /* Can be set by ACL */
6951ac6c 2047#ifdef WITH_CONTENT_SCAN
8768d548 2048f.no_mbox_unspool = FALSE; /* Can be set by ACL */
8523533c 2049#endif
8768d548
JH
2050f.submission_mode = FALSE; /* Can be set by ACL */
2051f.suppress_local_fixups = f.suppress_local_fixups_default; /* Can be set by ACL */
2052f.active_local_from_check = local_from_check; /* Can be set by ACL */
2053f.active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
90341c71
JH
2054sending_ip_address = NULL;
2055return_path = sender_address = NULL;
2056sender_data = NULL; /* Can be set by ACL */
c679ee08
JH
2057deliver_localpart_parent = deliver_localpart_orig = NULL;
2058deliver_domain_parent = deliver_domain_orig = NULL;
90341c71 2059callout_address = NULL;
2fe1a124 2060submission_name = NULL; /* Can be set by ACL */
059ec3d9
PH
2061raw_sender = NULL; /* After SMTP rewrite, before qualifying */
2062sender_address_unrewritten = NULL; /* Set only after verify rewrite */
2063sender_verified_list = NULL; /* No senders verified */
2064memset(sender_address_cache, 0, sizeof(sender_address_cache));
2065memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
6c1c3d1d 2066
059ec3d9 2067authenticated_sender = NULL;
8523533c
TK
2068#ifdef EXPERIMENTAL_BRIGHTMAIL
2069bmi_run = 0;
2070bmi_verdicts = NULL;
2071#endif
90341c71 2072dnslist_domain = dnslist_matched = NULL;
01067968
JH
2073#ifdef SUPPORT_SPF
2074spf_header_comment = spf_received = spf_result = spf_smtp_comment = NULL;
2075spf_result_guessed = FALSE;
2076#endif
80a47a2c 2077#ifndef DISABLE_DKIM
d342446f 2078dkim_cur_signer = dkim_signers =
b4757e36 2079dkim_signing_domain = dkim_signing_selector = dkim_signatures = NULL;
d342446f 2080dkim_cur_signer = dkim_signers = dkim_signing_domain = dkim_signing_selector = NULL;
8768d548 2081f.dkim_disable_verify = FALSE;
64b67b65 2082dkim_collect_input = 0;
d342446f
JH
2083dkim_verify_overall = dkim_verify_status = dkim_verify_reason = NULL;
2084dkim_key_length = 0;
2085dkim_verify_signers = US"$dkim_signers";
f7572e5a 2086#endif
b4757e36 2087#ifdef EXPERIMENTAL_DMARC
8768d548 2088f.dmarc_has_been_checked = f.dmarc_disable_verify = f.dmarc_enable_forensic = FALSE;
8aeef98a 2089dmarc_domain_policy = dmarc_status = dmarc_status_text =
6372d4c9 2090dmarc_used_domain = NULL;
f7572e5a 2091#endif
01067968
JH
2092#ifdef EXPERIMENTAL_ARC
2093arc_state = arc_state_reason = NULL;
b4757e36 2094#endif
aa368db3
JH
2095dsn_ret = 0;
2096dsn_envid = NULL;
90341c71 2097deliver_host = deliver_host_address = NULL; /* Can be set by ACL */
aa368db3
JH
2098#ifndef DISABLE_PRDR
2099prdr_requested = FALSE;
2100#endif
8c5d388a 2101#ifdef SUPPORT_I18N
d1a13eea
JH
2102message_smtputf8 = FALSE;
2103#endif
059ec3d9
PH
2104body_linecount = body_zerocount = 0;
2105
870f6ba8
TF
2106sender_rate = sender_rate_limit = sender_rate_period = NULL;
2107ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
2108 /* Note that ratelimiters_conn persists across resets. */
2109
38a0a95f 2110/* Reset message ACL variables */
47ca6d6c 2111
38a0a95f 2112acl_var_m = NULL;
059ec3d9
PH
2113
2114/* The message body variables use malloc store. They may be set if this is
2115not the first message in an SMTP session and the previous message caused them
2116to be referenced in an ACL. */
2117
90341c71 2118if (message_body)
059ec3d9
PH
2119 {
2120 store_free(message_body);
2121 message_body = NULL;
2122 }
2123
90341c71 2124if (message_body_end)
059ec3d9
PH
2125 {
2126 store_free(message_body_end);
2127 message_body_end = NULL;
2128 }
2129
2130/* Warning log messages are also saved in malloc store. They are saved to avoid
2131repetition in the same message, but it seems right to repeat them for different
4e88a19f 2132messages. */
059ec3d9 2133
90341c71 2134while (acl_warn_logged)
059ec3d9
PH
2135 {
2136 string_item *this = acl_warn_logged;
2137 acl_warn_logged = acl_warn_logged->next;
2138 store_free(this);
2139 }
90341c71 2140store_reset(reset_point);
059ec3d9
PH
2141}
2142
2143
2144
2145
2146
2147/*************************************************
2148* Initialize for incoming batched SMTP message *
2149*************************************************/
2150
2151/* This function is called from smtp_setup_msg() in the case when
2152smtp_batched_input is true. This happens when -bS is used to pass a whole batch
2153of messages in one file with SMTP commands between them. All errors must be
2154reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
2155relevant. After an error on a sender, or an invalid recipient, the remainder
2156of the message is skipped. The value of received_protocol is already set.
2157
2158Argument: none
2159Returns: > 0 message successfully started (reached DATA)
2160 = 0 QUIT read or end of file reached
2161 < 0 should not occur
2162*/
2163
2164static int
2165smtp_setup_batch_msg(void)
2166{
2167int done = 0;
2168void *reset_point = store_get(0);
2169
2170/* Save the line count at the start of each transaction - single commands
2171like HELO and RSET count as whole transactions. */
2172
2173bsmtp_transaction_linecount = receive_linecount;
2174
2175if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
2176
57cc2785 2177cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg");
059ec3d9
PH
2178smtp_reset(reset_point); /* Reset for start of message */
2179
2180/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
2181value. The values are 2 larger than the required yield of the function. */
2182
2183while (done <= 0)
2184 {
2185 uschar *errmess;
2186 uschar *recipient = NULL;
2187 int start, end, sender_domain, recipient_domain;
2188
bd8fbe36 2189 switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9
PH
2190 {
2191 /* The HELO/EHLO commands set sender_address_helo if they have
2192 valid data; otherwise they are ignored, except that they do
2193 a reset of the state. */
2194
2195 case HELO_CMD:
2196 case EHLO_CMD:
2197
db57e575
JH
2198 check_helo(smtp_cmd_data);
2199 /* Fall through */
059ec3d9
PH
2200
2201 case RSET_CMD:
db57e575
JH
2202 cancel_cutthrough_connection(TRUE, US"RSET received");
2203 smtp_reset(reset_point);
2204 bsmtp_transaction_linecount = receive_linecount;
2205 break;
059ec3d9
PH
2206
2207
2208 /* The MAIL FROM command requires an address as an operand. All we
2209 do here is to parse it for syntactic correctness. The form "<>" is
2210 a special case which converts into an empty string. The start/end
2211 pointers in the original are not used further for this address, as
2212 it is the canonical extracted address which is all that is kept. */
2213
2214 case MAIL_CMD:
db57e575
JH
2215 smtp_mailcmd_count++; /* Count for no-mail log */
2216 if (sender_address != NULL)
2217 /* The function moan_smtp_batch() does not return. */
2218 moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
059ec3d9 2219
db57e575
JH
2220 if (smtp_cmd_data[0] == 0)
2221 /* The function moan_smtp_batch() does not return. */
2222 moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
059ec3d9 2223
db57e575 2224 /* Reset to start of message */
059ec3d9 2225
db57e575
JH
2226 cancel_cutthrough_connection(TRUE, US"MAIL received");
2227 smtp_reset(reset_point);
059ec3d9 2228
db57e575 2229 /* Apply SMTP rewrite */
059ec3d9 2230
db57e575
JH
2231 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
2232 rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
2233 US"", global_rewrite_rules) : smtp_cmd_data;
059ec3d9 2234
db57e575 2235 /* Extract the address; the TRUE flag allows <> as valid */
059ec3d9 2236
db57e575
JH
2237 raw_sender =
2238 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
2239 TRUE);
059ec3d9 2240
db57e575
JH
2241 if (!raw_sender)
2242 /* The function moan_smtp_batch() does not return. */
2243 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9 2244
db57e575 2245 sender_address = string_copy(raw_sender);
059ec3d9 2246
db57e575 2247 /* Qualify unqualified sender addresses if permitted to do so. */
059ec3d9 2248
db57e575
JH
2249 if ( !sender_domain
2250 && sender_address[0] != 0 && sender_address[0] != '@')
8768d548 2251 if (f.allow_unqualified_sender)
db57e575
JH
2252 {
2253 sender_address = rewrite_address_qualify(sender_address, FALSE);
2254 DEBUG(D_receive) debug_printf("unqualified address %s accepted "
2255 "and rewritten\n", raw_sender);
2256 }
2257 /* The function moan_smtp_batch() does not return. */
2258 else
2259 moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
2260 "a domain");
2261 break;
059ec3d9
PH
2262
2263
2264 /* The RCPT TO command requires an address as an operand. All we do
2265 here is to parse it for syntactic correctness. There may be any number
2266 of RCPT TO commands, specifying multiple senders. We build them all into
2267 a data structure that is in argc/argv format. The start/end values
2268 given by parse_extract_address are not used, as we keep only the
2269 extracted address. */
2270
2271 case RCPT_CMD:
db57e575
JH
2272 if (!sender_address)
2273 /* The function moan_smtp_batch() does not return. */
2274 moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
059ec3d9 2275
db57e575
JH
2276 if (smtp_cmd_data[0] == 0)
2277 /* The function moan_smtp_batch() does not return. */
2278 moan_smtp_batch(smtp_cmd_buffer,
2279 "501 RCPT TO must have an address operand");
059ec3d9 2280
db57e575 2281 /* Check maximum number allowed */
059ec3d9 2282
db57e575
JH
2283 if (recipients_max > 0 && recipients_count + 1 > recipients_max)
2284 /* The function moan_smtp_batch() does not return. */
2285 moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
2286 recipients_max_reject? "552": "452");
059ec3d9 2287
db57e575
JH
2288 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
2289 recipient address */
059ec3d9 2290
db57e575
JH
2291 recipient = rewrite_existflags & rewrite_smtp
2292 ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
2293 global_rewrite_rules)
2294 : smtp_cmd_data;
059ec3d9 2295
db57e575
JH
2296 recipient = parse_extract_address(recipient, &errmess, &start, &end,
2297 &recipient_domain, FALSE);
059ec3d9 2298
db57e575
JH
2299 if (!recipient)
2300 /* The function moan_smtp_batch() does not return. */
2301 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9 2302
db57e575
JH
2303 /* If the recipient address is unqualified, qualify it if permitted. Then
2304 add it to the list of recipients. */
059ec3d9 2305
db57e575 2306 if (!recipient_domain)
8768d548 2307 if (f.allow_unqualified_recipient)
db57e575
JH
2308 {
2309 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
2310 recipient);
2311 recipient = rewrite_address_qualify(recipient, TRUE);
2312 }
2313 /* The function moan_smtp_batch() does not return. */
2314 else
2315 moan_smtp_batch(smtp_cmd_buffer,
2316 "501 recipient address must contain a domain");
2317
2318 receive_add_recipient(recipient, -1);
2319 break;
059ec3d9
PH
2320
2321
2322 /* The DATA command is legal only if it follows successful MAIL FROM
2323 and RCPT TO commands. This function is complete when a valid DATA
2324 command is encountered. */
2325
2326 case DATA_CMD:
db57e575
JH
2327 if (!sender_address || recipients_count <= 0)
2328 /* The function moan_smtp_batch() does not return. */
2329 if (!sender_address)
2330 moan_smtp_batch(smtp_cmd_buffer,
2331 "503 MAIL FROM:<sender> command must precede DATA");
2332 else
2333 moan_smtp_batch(smtp_cmd_buffer,
2334 "503 RCPT TO:<recipient> must precede DATA");
059ec3d9 2335 else
db57e575
JH
2336 {
2337 done = 3; /* DATA successfully achieved */
2338 message_ended = END_NOTENDED; /* Indicate in middle of message */
2339 }
2340 break;
059ec3d9
PH
2341
2342
2343 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
2344
2345 case VRFY_CMD:
2346 case EXPN_CMD:
2347 case HELP_CMD:
2348 case NOOP_CMD:
2349 case ETRN_CMD:
db57e575
JH
2350 bsmtp_transaction_linecount = receive_linecount;
2351 break;
059ec3d9
PH
2352
2353
2354 case EOF_CMD:
2355 case QUIT_CMD:
db57e575
JH
2356 done = 2;
2357 break;
059ec3d9
PH
2358
2359
2360 case BADARG_CMD:
db57e575
JH
2361 /* The function moan_smtp_batch() does not return. */
2362 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
2363 break;
059ec3d9
PH
2364
2365
2366 case BADCHAR_CMD:
db57e575
JH
2367 /* The function moan_smtp_batch() does not return. */
2368 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
2369 break;
059ec3d9
PH
2370
2371
2372 default:
db57e575
JH
2373 /* The function moan_smtp_batch() does not return. */
2374 moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
2375 break;
059ec3d9
PH
2376 }
2377 }
2378
2379return done - 2; /* Convert yield values */
2380}
2381
2382
2383
2384
13c7874e 2385#ifdef SUPPORT_TLS
cf0c6164
JH
2386static BOOL
2387smtp_log_tls_fail(uschar * errstr)
2388{
2389uschar * conn_info = smtp_get_connection_info();
2390
2391if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
2392/* I'd like to get separated H= here, but too hard for now */
2393
2394log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
2395return FALSE;
2396}
13c7874e 2397#endif
cf0c6164
JH
2398
2399
a2673768
JH
2400
2401
2402#ifdef TCP_FASTOPEN
2403static void
2404tfo_in_check(void)
2405{
2406# ifdef TCP_INFO
2407struct tcp_info tinfo;
2408socklen_t len = sizeof(tinfo);
2409
ee8b8090 2410if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
dbcb6d0a 2411#ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11 does not seem to have this yet */
ee8b8090
JH
2412 if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA)
2413 {
2414 DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
2415 f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE;
2416 }
dbcb6d0a
JH
2417 else
2418#endif
2419 if (tinfo.tcpi_state == TCP_SYN_RECV)
ee8b8090
JH
2420 {
2421 DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
2422 f.tcp_in_fastopen = TRUE;
2423 }
a2673768
JH
2424# endif
2425}
2426#endif
2427
2428
059ec3d9
PH
2429/*************************************************
2430* Start an SMTP session *
2431*************************************************/
2432
2433/* This function is called at the start of an SMTP session. Thereafter,
2434smtp_setup_msg() is called to initiate each separate message. This
2435function does host-specific testing, and outputs the banner line.
2436
2437Arguments: none
2438Returns: FALSE if the session can not continue; something has
2439 gone wrong, or the connection to the host is blocked
2440*/
2441
2442BOOL
2443smtp_start_session(void)
2444{
acec9514 2445int esclen;
4e88a19f
PH
2446uschar *user_msg, *log_msg;
2447uschar *code, *esc;
acec9514
JH
2448uschar *p, *s;
2449gstring * ss;
059ec3d9 2450
0f1a8658 2451gettimeofday(&smtp_connection_start, NULL);
b4ed4da0
PH
2452for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
2453 smtp_connection_had[smtp_ch_index] = SCH_NONE;
2454smtp_ch_index = 0;
2455
00f00ca5
PH
2456/* Default values for certain variables */
2457
88752192 2458fl.helo_seen = fl.esmtp = fl.helo_accept_junk = FALSE;
b4ed4da0 2459smtp_mailcmd_count = 0;
059ec3d9
PH
2460count_nonmail = TRUE_UNSET;
2461synprot_error_count = unknown_command_count = nonmail_command_count = 0;
2462smtp_delay_mail = smtp_rlm_base;
88752192 2463fl.auth_advertised = FALSE;
8768d548
JH
2464f.smtp_in_pipelining_advertised = f.smtp_in_pipelining_used = FALSE;
2465f.pipelining_enable = TRUE;
059ec3d9 2466sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
88752192 2467fl.smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
059ec3d9 2468
33d73e3b
PH
2469/* If receiving by -bs from a trusted user, or testing with -bh, we allow
2470authentication settings from -oMaa to remain in force. */
2471
8768d548 2472if (!host_checking && !f.sender_host_notsocket)
c44ff8be 2473 sender_host_auth_pubname = sender_host_authenticated = NULL;
059ec3d9
PH
2474authenticated_by = NULL;
2475
2476#ifdef SUPPORT_TLS
817d9f57 2477tls_in.cipher = tls_in.peerdn = NULL;
9d1c15ef
JH
2478tls_in.ourcert = tls_in.peercert = NULL;
2479tls_in.sni = NULL;
44662487 2480tls_in.ocsp = OCSP_NOT_REQ;
88752192 2481fl.tls_advertised = FALSE;
8ac90765 2482# ifdef EXPERIMENTAL_REQUIRETLS
88752192 2483fl.requiretls_advertised = FALSE;
8ac90765 2484# endif
059ec3d9 2485#endif
88752192 2486fl.dsn_advertised = FALSE;
8c5d388a 2487#ifdef SUPPORT_I18N
88752192 2488fl.smtputf8_advertised = FALSE;
d1a13eea 2489#endif
059ec3d9
PH
2490
2491/* Reset ACL connection variables */
2492
38a0a95f 2493acl_var_c = NULL;
059ec3d9 2494
ca86f471 2495/* Allow for trailing 0 in the command and data buffers. */
3ee512ff 2496
bd8fbe36 2497if (!(smtp_cmd_buffer = US malloc(2*SMTP_CMD_BUFFER_SIZE + 2)))
059ec3d9
PH
2498 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2499 "malloc() failed for SMTP command buffer");
40c90bca 2500
2416c261 2501smtp_cmd_buffer[0] = 0;
bd8fbe36 2502smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1;
059ec3d9
PH
2503
2504/* For batched input, the protocol setting can be overridden from the
2505command line by a trusted caller. */
2506
2507if (smtp_batched_input)
2508 {
40c90bca 2509 if (!received_protocol) received_protocol = US"local-bsmtp";
059ec3d9
PH
2510 }
2511
2512/* For non-batched SMTP input, the protocol setting is forced here. It will be
2513reset later if any of EHLO/AUTH/STARTTLS are received. */
2514
2515else
2516 received_protocol =
e524074d 2517 (sender_host_address ? protocols : protocols_local) [pnormal];
059ec3d9
PH
2518
2519/* Set up the buffer for inputting using direct read() calls, and arrange to
ecce6d9a
JH
2520call the local functions instead of the standard C ones. Place a NUL at the
2521end of the buffer to safety-stop C-string reads from it. */
059ec3d9 2522
5903c6ff 2523if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE)))
059ec3d9 2524 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
ecce6d9a 2525smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0';
40c90bca 2526
059ec3d9 2527receive_getc = smtp_getc;
0d81dabc 2528receive_getbuf = smtp_getbuf;
584e96c6 2529receive_get_cache = smtp_get_cache;
059ec3d9
PH
2530receive_ungetc = smtp_ungetc;
2531receive_feof = smtp_feof;
2532receive_ferror = smtp_ferror;
58eb016e 2533receive_smtp_buffered = smtp_buffered;
059ec3d9
PH
2534smtp_inptr = smtp_inend = smtp_inbuffer;
2535smtp_had_eof = smtp_had_error = 0;
2536
2537/* Set up the message size limit; this may be host-specific */
2538
d45b1de8 2539thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
db57e575 2540if (expand_string_message)
059ec3d9
PH
2541 {
2542 if (thismessage_size_limit == -1)
2543 log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
2544 "%s", expand_string_message);
2545 else
2546 log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: "
2547 "%s", expand_string_message);
2548 smtp_closedown(US"Temporary local problem - please try later");
2549 return FALSE;
2550 }
2551
2552/* When a message is input locally via the -bs or -bS options, sender_host_
2553unknown is set unless -oMa was used to force an IP address, in which case it
2554is checked like a real remote connection. When -bs is used from inetd, this
2555flag is not set, causing the sending host to be checked. The code that deals
2556with IP source routing (if configured) is never required for -bs or -bS and
2557the flag sender_host_notsocket is used to suppress it.
2558
2559If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
2560reserve for certain hosts and/or networks. */
2561
8768d548 2562if (!f.sender_host_unknown)
059ec3d9
PH
2563 {
2564 int rc;
2565 BOOL reserved_host = FALSE;
2566
2567 /* Look up IP options (source routing info) on the socket if this is not an
2568 -oMa "host", and if any are found, log them and drop the connection.
2569
2570 Linux (and others now, see below) is different to everyone else, so there
2571 has to be some conditional compilation here. Versions of Linux before 2.1.15
2572 used a structure whose name was "options". Somebody finally realized that
2573 this name was silly, and it got changed to "ip_options". I use the
2574 newer name here, but there is a fudge in the script that sets up os.h
2575 to define a macro in older Linux systems.
2576
2577 Sigh. Linux is a fast-moving target. Another generation of Linux uses
2578 glibc 2, which has chosen ip_opts for the structure name. This is now
2579 really a glibc thing rather than a Linux thing, so the condition name
2580 has been changed to reflect this. It is relevant also to GNU/Hurd.
2581
2582 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
2583 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
2584 a special macro defined in the os.h file.
2585
2586 Some DGUX versions on older hardware appear not to support IP options at
2587 all, so there is now a general macro which can be set to cut out this
2588 support altogether.
2589
2590 How to do this properly in IPv6 is not yet known. */
2591
e0574cb5 2592#if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
059ec3d9
PH
2593
2594 #ifdef GLIBC_IP_OPTIONS
2595 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
2596 #define OPTSTYLE 1
2597 #else
2598 #define OPTSTYLE 2
2599 #endif
2600 #elif defined DARWIN_IP_OPTIONS
2601 #define OPTSTYLE 2
2602 #else
2603 #define OPTSTYLE 3
2604 #endif
2605
8768d548 2606 if (!host_checking && !f.sender_host_notsocket)
059ec3d9
PH
2607 {
2608 #if OPTSTYLE == 1
36a3b041 2609 EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
059ec3d9
PH
2610 struct ip_options *ipopt = store_get(optlen);
2611 #elif OPTSTYLE == 2
2612 struct ip_opts ipoptblock;
2613 struct ip_opts *ipopt = &ipoptblock;
36a3b041 2614 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2615 #else
2616 struct ipoption ipoptblock;
2617 struct ipoption *ipopt = &ipoptblock;
36a3b041 2618 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2619 #endif
2620
2621 /* Occasional genuine failures of getsockopt() have been seen - for
2622 example, "reset by peer". Therefore, just log and give up on this
2623 call, unless the error is ENOPROTOOPT. This error is given by systems
2624 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
2625 of writing. So for that error, carry on - we just can't do an IP options
2626 check. */
2627
2628 DEBUG(D_receive) debug_printf("checking for IP options\n");
2629
5903c6ff 2630 if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, US (ipopt),
059ec3d9
PH
2631 &optlen) < 0)
2632 {
2633 if (errno != ENOPROTOOPT)
2634 {
2635 log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
2636 host_and_ident(FALSE), strerror(errno));
925ac8e4 2637 smtp_printf("451 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2638 return FALSE;
2639 }
2640 }
2641
2642 /* Deal with any IP options that are set. On the systems I have looked at,
2643 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
2644 more logging data than will fit in big_buffer. Nevertheless, after somebody
2645 questioned this code, I've added in some paranoid checking. */
2646
2647 else if (optlen > 0)
2648 {
2649 uschar *p = big_buffer;
2650 uschar *pend = big_buffer + big_buffer_size;
2651 uschar *opt, *adptr;
2652 int optcount;
2653 struct in_addr addr;
2654
2655 #if OPTSTYLE == 1
5903c6ff 2656 uschar *optstart = US (ipopt->__data);
059ec3d9 2657 #elif OPTSTYLE == 2
5903c6ff 2658 uschar *optstart = US (ipopt->ip_opts);
059ec3d9 2659 #else
5903c6ff 2660 uschar *optstart = US (ipopt->ipopt_list);
059ec3d9
PH
2661 #endif
2662
2663 DEBUG(D_receive) debug_printf("IP options exist\n");
2664
2665 Ustrcpy(p, "IP options on incoming call:");
2666 p += Ustrlen(p);
2667
2668 for (opt = optstart; opt != NULL &&
5903c6ff 2669 opt < US (ipopt) + optlen;)
059ec3d9
PH
2670 {
2671 switch (*opt)
2672 {
2673 case IPOPT_EOL:
2674 opt = NULL;
2675 break;
2676
2677 case IPOPT_NOP:
2678 opt++;
2679 break;
2680
2681 case IPOPT_SSRR:
2682 case IPOPT_LSRR:
2683 if (!string_format(p, pend-p, " %s [@%s",
2684 (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
2685 #if OPTSTYLE == 1
2686 inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
2687 #elif OPTSTYLE == 2
2688 inet_ntoa(ipopt->ip_dst)))
2689 #else
2690 inet_ntoa(ipopt->ipopt_dst)))
2691 #endif
2692 {
2693 opt = NULL;
2694 break;
2695 }
2696
2697 p += Ustrlen(p);
2698 optcount = (opt[1] - 3) / sizeof(struct in_addr);
2699 adptr = opt + 3;
2700 while (optcount-- > 0)
2701 {
2702 memcpy(&addr, adptr, sizeof(addr));
2703 if (!string_format(p, pend - p - 1, "%s%s",
2704 (optcount == 0)? ":" : "@", inet_ntoa(addr)))
2705 {
2706 opt = NULL;
2707 break;
2708 }
2709 p += Ustrlen(p);
2710 adptr += sizeof(struct in_addr);
2711 }
2712 *p++ = ']';
2713 opt += opt[1];
2714 break;
2715
2716 default:
2717 {
2718 int i;
2719 if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
2720 Ustrcat(p, "[ ");
2721 p += 2;
2722 for (i = 0; i < opt[1]; i++)
5976eb99 2723 p += sprintf(CS p, "%2.2x ", opt[i]);
059ec3d9
PH
2724 *p++ = ']';
2725 }
2726 opt += opt[1];
2727 break;
2728 }
2729 }
2730
2731 *p = 0;
2732 log_write(0, LOG_MAIN, "%s", big_buffer);
2733
2734 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2735
2736 log_write(0, LOG_MAIN|LOG_REJECT,
2737 "connection from %s refused (IP options)", host_and_ident(FALSE));
2738
925ac8e4 2739 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2740 return FALSE;
2741 }
2742
2743 /* Length of options = 0 => there are no options */
2744
2745 else DEBUG(D_receive) debug_printf("no IP options found\n");
2746 }
e0574cb5 2747#endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
059ec3d9
PH
2748
2749 /* Set keep-alive in socket options. The option is on by default. This
2750 setting is an attempt to get rid of some hanging connections that stick in
2751 read() when the remote end (usually a dialup) goes away. */
2752
8768d548 2753 if (smtp_accept_keepalive && !f.sender_host_notsocket)
059ec3d9
PH
2754 ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
2755
2756 /* If the current host matches host_lookup, set the name by doing a
2757 reverse lookup. On failure, sender_host_name will be NULL and
2758 host_lookup_failed will be TRUE. This may or may not be serious - optional
2759 checks later. */
2760
2761 if (verify_check_host(&host_lookup) == OK)
2762 {
2763 (void)host_name_lookup();
2764 host_build_sender_fullhost();
2765 }
2766
2767 /* Delay this until we have the full name, if it is looked up. */
2768
2769 set_process_info("handling incoming connection from %s",
2770 host_and_ident(FALSE));
2771
1ad6489e
JH
2772 /* Expand smtp_receive_timeout, if needed */
2773
2774 if (smtp_receive_timeout_s)
2775 {
2776 uschar * exp;
2777 if ( !(exp = expand_string(smtp_receive_timeout_s))
2778 || !(*exp)
2779 || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0
2780 )
2781 log_write(0, LOG_MAIN|LOG_PANIC,
2782 "bad value for smtp_receive_timeout: '%s'", exp ? exp : US"");
2783 }
2784
059ec3d9
PH
2785 /* Test for explicit connection rejection */
2786
2787 if (verify_check_host(&host_reject_connection) == OK)
2788 {
2789 log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
2790 "from %s (host_reject_connection)", host_and_ident(FALSE));
925ac8e4 2791 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2792 return FALSE;
2793 }
2794
afb3eaaf
PH
2795 /* Test with TCP Wrappers if so configured. There is a problem in that
2796 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2797 such as disks dying. In these cases, it is desirable to reject with a 4xx
2798 error instead of a 5xx error. There isn't a "right" way to detect such
2799 problems. The following kludge is used: errno is zeroed before calling
2800 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2801 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2802 not exist). */
059ec3d9 2803
1811cb4c 2804#ifdef USE_TCP_WRAPPERS
afb3eaaf 2805 errno = 0;
1811cb4c 2806 if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name)))
5dc43717
JJ
2807 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
2808 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
2809 expand_string_message);
1811cb4c 2810
5dc43717 2811 if (!hosts_ctl(tcp_wrappers_name,
1811cb4c
JH
2812 sender_host_name ? CS sender_host_name : STRING_UNKNOWN,
2813 sender_host_address ? CS sender_host_address : STRING_UNKNOWN,
2814 sender_ident ? CS sender_ident : STRING_UNKNOWN))
059ec3d9 2815 {
afb3eaaf
PH
2816 if (errno == 0 || errno == ENOENT)
2817 {
2818 HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
2819 log_write(L_connection_reject,
2820 LOG_MAIN|LOG_REJECT, "refused connection from %s "
2821 "(tcp wrappers)", host_and_ident(FALSE));
925ac8e4 2822 smtp_printf("554 SMTP service not available\r\n", FALSE);
afb3eaaf
PH
2823 }
2824 else
2825 {
2826 int save_errno = errno;
2827 HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
2828 "errno value %d\n", save_errno);
2829 log_write(L_connection_reject,
2830 LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
2831 "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
925ac8e4 2832 smtp_printf("451 Temporary local problem - please try later\r\n", FALSE);
afb3eaaf 2833 }
059ec3d9
PH
2834 return FALSE;
2835 }
1811cb4c 2836#endif
059ec3d9 2837
b01dd148
PH
2838 /* Check for reserved slots. The value of smtp_accept_count has already been
2839 incremented to include this process. */
059ec3d9
PH
2840
2841 if (smtp_accept_max > 0 &&
b01dd148 2842 smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
059ec3d9
PH
2843 {
2844 if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
2845 {
2846 log_write(L_connection_reject,
2847 LOG_MAIN, "temporarily refused connection from %s: not in "
2848 "reserve list: connected=%d max=%d reserve=%d%s",
b01dd148 2849 host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
059ec3d9
PH
2850 smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
2851 smtp_printf("421 %s: Too many concurrent SMTP connections; "
925ac8e4 2852 "please try again later\r\n", FALSE, smtp_active_hostname);
059ec3d9
PH
2853 return FALSE;
2854 }
2855 reserved_host = TRUE;
2856 }
2857
2858 /* If a load level above which only messages from reserved hosts are
2859 accepted is set, check the load. For incoming calls via the daemon, the
2860 check is done in the superior process if there are no reserved hosts, to
2861 save a fork. In all cases, the load average will already be available
2862 in a global variable at this point. */
2863
2864 if (smtp_load_reserve >= 0 &&
2865 load_average > smtp_load_reserve &&
2866 !reserved_host &&
2867 verify_check_host(&smtp_reserve_hosts) != OK)
2868 {
2869 log_write(L_connection_reject,
2870 LOG_MAIN, "temporarily refused connection from %s: not in "
2871 "reserve list and load average = %.2f", host_and_ident(FALSE),
2872 (double)load_average/1000.0);
925ac8e4 2873 smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE,
059ec3d9
PH
2874 smtp_active_hostname);
2875 return FALSE;
2876 }
2877
2878 /* Determine whether unqualified senders or recipients are permitted
2879 for this host. Unfortunately, we have to do this every time, in order to
2880 set the flags so that they can be inspected when considering qualifying
2881 addresses in the headers. For a site that permits no qualification, this
2882 won't take long, however. */
2883
8768d548 2884 f.allow_unqualified_sender =
059ec3d9
PH
2885 verify_check_host(&sender_unqualified_hosts) == OK;
2886
8768d548 2887 f.allow_unqualified_recipient =
059ec3d9
PH
2888 verify_check_host(&recipient_unqualified_hosts) == OK;
2889
2890 /* Determine whether HELO/EHLO is required for this host. The requirement
2891 can be hard or soft. */
2892
88752192
JH
2893 fl.helo_required = verify_check_host(&helo_verify_hosts) == OK;
2894 if (!fl.helo_required)
2895 fl.helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
059ec3d9
PH
2896
2897 /* Determine whether this hosts is permitted to send syntactic junk
2898 after a HELO or EHLO command. */
2899
88752192 2900 fl.helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
059ec3d9
PH
2901 }
2902
2903/* For batch SMTP input we are now done. */
2904
2905if (smtp_batched_input) return TRUE;
2906
a3c86431
TL
2907/* If valid Proxy Protocol source is connecting, set up session.
2908 * Failure will not allow any SMTP function other than QUIT. */
1811cb4c
JH
2909
2910#ifdef SUPPORT_PROXY
a3c86431 2911proxy_session = FALSE;
8768d548 2912f.proxy_session_failed = FALSE;
a3c86431 2913if (check_proxy_protocol_host())
1811cb4c
JH
2914 setup_proxy_protocol_host();
2915#endif
2916
2917 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2918 smtps port for use with older style SSL MTAs. */
2919
2920#ifdef SUPPORT_TLS
69d8eed7
JH
2921 if (tls_in.on_connect)
2922 {
2923 if (tls_server_start(tls_require_ciphers, &user_msg) != OK)
2924 return smtp_log_tls_fail(user_msg);
2925 cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
2926 }
a3c86431
TL
2927#endif
2928
1811cb4c 2929/* Run the connect ACL if it exists */
059ec3d9 2930
4e88a19f 2931user_msg = NULL;
3cc3f762 2932if (acl_smtp_connect)
059ec3d9
PH
2933 {
2934 int rc;
3cc3f762
JH
2935 if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
2936 &log_msg)) != OK)
059ec3d9 2937 {
3cc3f762 2938 (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
059ec3d9
PH
2939 return FALSE;
2940 }
2941 }
2942
2943/* Output the initial message for a two-way SMTP connection. It may contain
2944newlines, which then cause a multi-line response to be given. */
2945
4e88a19f
PH
2946code = US"220"; /* Default status code */
2947esc = US""; /* Default extended status code */
2948esclen = 0; /* Length of esc */
2949
d4ff61d1 2950if (!user_msg)
4e88a19f 2951 {
d4ff61d1 2952 if (!(s = expand_string(smtp_banner)))
4e88a19f
PH
2953 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
2954 "failed: %s", smtp_banner, expand_string_message);
2955 }
2956else
2957 {
2958 int codelen = 3;
2959 s = user_msg;
4f6ae5c3 2960 smtp_message_code(&code, &codelen, &s, NULL, TRUE);
d6a96edc 2961 if (codelen > 4)
4e88a19f
PH
2962 {
2963 esc = code + 4;
2964 esclen = codelen - 4;
2965 }
2966 }
059ec3d9
PH
2967
2968/* Remove any terminating newlines; might as well remove trailing space too */
2969
2970p = s + Ustrlen(s);
2971while (p > s && isspace(p[-1])) p--;
2972*p = 0;
2973
2974/* It seems that CC:Mail is braindead, and assumes that the greeting message
2975is all contained in a single IP packet. The original code wrote out the
2976greeting using several calls to fprint/fputc, and on busy servers this could
2977cause it to be split over more than one packet - which caused CC:Mail to fall
2978over when it got the second part of the greeting after sending its first
2979command. Sigh. To try to avoid this, build the complete greeting message
2980first, and output it in one fell swoop. This gives a better chance of it
2981ending up as a single packet. */
2982
acec9514 2983ss = string_get(256);
059ec3d9
PH
2984
2985p = s;
2986do /* At least once, in case we have an empty string */
2987 {
2988 int len;
2989 uschar *linebreak = Ustrchr(p, '\n');
acec9514 2990 ss = string_catn(ss, code, 3);
db57e575 2991 if (!linebreak)
059ec3d9
PH
2992 {
2993 len = Ustrlen(p);
acec9514 2994 ss = string_catn(ss, US" ", 1);
059ec3d9
PH
2995 }
2996 else
2997 {
2998 len = linebreak - p;
acec9514 2999 ss = string_catn(ss, US"-", 1);
059ec3d9 3000 }
acec9514
JH
3001 ss = string_catn(ss, esc, esclen);
3002 ss = string_catn(ss, p, len);
3003 ss = string_catn(ss, US"\r\n", 2);
059ec3d9 3004 p += len;
db57e575 3005 if (linebreak) p++;
059ec3d9 3006 }
db57e575 3007while (*p);
059ec3d9 3008
059ec3d9
PH
3009/* Before we write the banner, check that there is no input pending, unless
3010this synchronisation check is disabled. */
3011
ee8b8090
JH
3012#ifdef EXPERIMENTAL_PIPE_CONNECT
3013fl.pipe_connect_acceptable =
3014 sender_host_address && verify_check_host(&pipe_connect_advertise_hosts) == OK;
3015
a14e5636 3016if (!check_sync())
ee8b8090
JH
3017 if (fl.pipe_connect_acceptable)
3018 f.smtp_in_early_pipe_used = TRUE;
3019 else
3020#else
3021if (!check_sync())
3022#endif
3023 {
3024 unsigned n = smtp_inend - smtp_inptr;
3025 if (n > 32) n = 32;
3026
3027 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
3028 "synchronization error (input sent without waiting for greeting): "
3029 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
3030 string_printing(string_copyn(smtp_inptr, n)));
3031 smtp_printf("554 SMTP synchronization error\r\n", FALSE);
3032 return FALSE;
3033 }
059ec3d9
PH
3034
3035/* Now output the banner */
ee8b8090 3036/*XXX the ehlo-resp code does its own tls/nontls bit. Maybe subroutine that? */
059ec3d9 3037
ee8b8090
JH
3038smtp_printf("%s",
3039#ifdef EXPERIMENTAL_PIPE_CONNECT
3040 fl.pipe_connect_acceptable && pipeline_connect_sends(),
3041#else
3042 FALSE,
3043#endif
3044 string_from_gstring(ss));
a2673768
JH
3045
3046/* Attempt to see if we sent the banner before the last ACK of the 3-way
3047handshake arrived. If so we must have managed a TFO. */
3048
3049#ifdef TCP_FASTOPEN
3050tfo_in_check();
3051#endif
3052
059ec3d9
PH
3053return TRUE;
3054}
3055
3056
3057
3058
3059
3060/*************************************************
3061* Handle SMTP syntax and protocol errors *
3062*************************************************/
3063
3064/* Write to the log for SMTP syntax errors in incoming commands, if configured
3065to do so. Then transmit the error response. The return value depends on the
3066number of syntax and protocol errors in this SMTP session.
3067
3068Arguments:
3069 type error type, given as a log flag bit
3070 code response code; <= 0 means don't send a response
3071 data data to reflect in the response (can be NULL)
3072 errmess the error message
3073
3074Returns: -1 limit of syntax/protocol errors NOT exceeded
3075 +1 limit of syntax/protocol errors IS exceeded
3076
3077These values fit in with the values of the "done" variable in the main
3078processing loop in smtp_setup_msg(). */
3079
3080static int
3081synprot_error(int type, int code, uschar *data, uschar *errmess)
3082{
3083int yield = -1;
3084
3085log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
3086 (type == L_smtp_syntax_error)? "syntax" : "protocol",
3ee512ff 3087 string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
059ec3d9
PH
3088
3089if (++synprot_error_count > smtp_max_synprot_errors)
3090 {
3091 yield = 1;
3092 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
3093 "syntax or protocol errors (last command was \"%s\")",
0ebc4d69 3094 host_and_ident(FALSE), string_printing(smtp_cmd_buffer));
059ec3d9
PH
3095 }
3096
3097if (code > 0)
3098 {
925ac8e4
JH
3099 smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ',
3100 data ? data : US"", data ? US": " : US"", errmess);
059ec3d9 3101 if (yield == 1)
925ac8e4 3102 smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code);
059ec3d9
PH
3103 }
3104
3105return yield;
3106}
3107
3108
3109
3110
3111/*************************************************
059ec3d9
PH
3112* Send SMTP response, possibly multiline *
3113*************************************************/
3114
3115/* There are, it seems, broken clients out there that cannot handle multiline
3116responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
3117output nothing for non-final calls, and only the first line for anything else.
3118
3119Arguments:
a5bd321b 3120 code SMTP code, may involve extended status codes
d6a96edc 3121 codelen length of smtp code; if > 4 there's an ESC
059ec3d9
PH
3122 final FALSE if the last line isn't the final line
3123 msg message text, possibly containing newlines
3124
3125Returns: nothing
3126*/
3127
3128void
a5bd321b 3129smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
059ec3d9 3130{
a5bd321b
PH
3131int esclen = 0;
3132uschar *esc = US"";
3133
8768d548 3134if (!final && f.no_multiline_responses) return;
059ec3d9 3135
d6a96edc 3136if (codelen > 4)
a5bd321b
PH
3137 {
3138 esc = code + 4;
3139 esclen = codelen - 4;
3140 }
3141
2679d413
PH
3142/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
3143have had the same. Note: this code is also present in smtp_printf(). It would
3144be tidier to have it only in one place, but when it was added, it was easier to
3145do it that way, so as not to have to mess with the code for the RCPT command,
3146which sometimes uses smtp_printf() and sometimes smtp_respond(). */
3147
88752192 3148if (fl.rcpt_in_progress)
2679d413
PH
3149 {
3150 if (rcpt_smtp_response == NULL)
3151 rcpt_smtp_response = string_copy(msg);
88752192 3152 else if (fl.rcpt_smtp_response_same &&
2679d413 3153 Ustrcmp(rcpt_smtp_response, msg) != 0)
88752192
JH
3154 fl.rcpt_smtp_response_same = FALSE;
3155 fl.rcpt_in_progress = FALSE;
2679d413
PH
3156 }
3157
e5de01f0 3158/* Now output the message, splitting it up into multiple lines if necessary.
925ac8e4
JH
3159We only handle pipelining these responses as far as nonfinal/final groups,
3160not the whole MAIL/RCPT/DATA response set. */
2679d413 3161
059ec3d9
PH
3162for (;;)
3163 {
3164 uschar *nl = Ustrchr(msg, '\n');
3165 if (nl == NULL)
3166 {
925ac8e4 3167 smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg);
059ec3d9
PH
3168 return;
3169 }
8768d548 3170 else if (nl[1] == 0 || f.no_multiline_responses)
059ec3d9 3171 {
925ac8e4 3172 smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc,
a5bd321b 3173 (int)(nl - msg), msg);
059ec3d9
PH
3174 return;
3175 }
3176 else
3177 {
925ac8e4 3178 smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg);
059ec3d9
PH
3179 msg = nl + 1;
3180 while (isspace(*msg)) msg++;
3181 }
3182 }
3183}
3184
3185
3186
3187
3188/*************************************************
4e88a19f
PH
3189* Parse user SMTP message *
3190*************************************************/
3191
3192/* This function allows for user messages overriding the response code details
3193by providing a suitable response code string at the start of the message
3194user_msg. Check the message for starting with a response code and optionally an
3195extended status code. If found, check that the first digit is valid, and if so,
3196change the code pointer and length to use the replacement. An invalid code
3197causes a panic log; in this case, if the log messages is the same as the user
3198message, we must also adjust the value of the log message to show the code that
3199is actually going to be used (the original one).
3200
3201This function is global because it is called from receive.c as well as within
3202this module.
3203
d6a96edc
PH
3204Note that the code length returned includes the terminating whitespace
3205character, which is always included in the regex match.
3206
4e88a19f
PH
3207Arguments:
3208 code SMTP code, may involve extended status codes
d6a96edc 3209 codelen length of smtp code; if > 4 there's an ESC
4e88a19f
PH
3210 msg message text
3211 log_msg optional log message, to be adjusted with the new SMTP code
4f6ae5c3 3212 check_valid if true, verify the response code
4e88a19f
PH
3213
3214Returns: nothing
3215*/
3216
3217void
4f6ae5c3
JH
3218smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg,
3219 BOOL check_valid)
4e88a19f
PH
3220{
3221int n;
3222int ovector[3];
3223
4f6ae5c3 3224if (!msg || !*msg) return;
4e88a19f 3225
4f6ae5c3
JH
3226if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
3227 PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return;
4e88a19f 3228
4f6ae5c3 3229if (check_valid && (*msg)[0] != (*code)[0])
4e88a19f
PH
3230 {
3231 log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
3232 "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
3233 if (log_msg != NULL && *log_msg == *msg)
3234 *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
3235 }
3236else
3237 {
3238 *code = *msg;
3239 *codelen = ovector[1]; /* Includes final space */
3240 }
3241*msg += ovector[1]; /* Chop the code off the message */
3242return;
3243}
3244
3245
3246
3247
3248/*************************************************
059ec3d9
PH
3249* Handle an ACL failure *
3250*************************************************/
3251
3252/* This function is called when acl_check() fails. As well as calls from within
3253this module, it is called from receive.c for an ACL after DATA. It sorts out
5b6f7658 3254logging the incident, and sends the error response. A message containing
059ec3d9
PH
3255newlines is turned into a multiline SMTP response, but for logging, only the
3256first line is used.
3257
a5bd321b
PH
3258There's a table of default permanent failure response codes to use in
3259globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
3260defaults disabled in Exim. However, discussion in connection with RFC 821bis
3261(aka RFC 2821) has concluded that the response should be 252 in the disabled
3262state, because there are broken clients that try VRFY before RCPT. A 5xx
3263response should be given only when the address is positively known to be
4f6ae5c3
JH
3264undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
3265no explicit code, but if there is one we let it know best.
3266Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
a5bd321b
PH
3267
3268From Exim 4.63, it is possible to override the response code details by
3269providing a suitable response code string at the start of the message provided
3270in user_msg. The code's first digit is checked for validity.
059ec3d9
PH
3271
3272Arguments:
4f6ae5c3
JH
3273 where where the ACL was called from
3274 rc the failure code
3275 user_msg a message that can be included in an SMTP response
3276 log_msg a message for logging
059ec3d9
PH
3277
3278Returns: 0 in most cases
3279 2 if the failure code was FAIL_DROP, in which case the
3280 SMTP connection should be dropped (this value fits with the
3281 "done" variable in smtp_setup_msg() below)
3282*/
3283
3284int
3285smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
3286{
059ec3d9 3287BOOL drop = rc == FAIL_DROP;
a5bd321b 3288int codelen = 3;
a5bd321b 3289uschar *smtp_code;
059ec3d9
PH
3290uschar *lognl;
3291uschar *sender_info = US"";
64ffc24f 3292uschar *what =
8523533c 3293#ifdef WITH_CONTENT_SCAN
3cc3f762 3294 where == ACL_WHERE_MIME ? US"during MIME ACL checks" :
8e669ac1 3295#endif
3cc3f762
JH
3296 where == ACL_WHERE_PREDATA ? US"DATA" :
3297 where == ACL_WHERE_DATA ? US"after DATA" :
8ccd00b1 3298#ifndef DISABLE_PRDR
3cc3f762 3299 where == ACL_WHERE_PRDR ? US"after DATA PRDR" :
fd98a5c6 3300#endif
3cc3f762
JH
3301 smtp_cmd_data ?
3302 string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) :
3303 string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]);
059ec3d9
PH
3304
3305if (drop) rc = FAIL;
3306
4e88a19f 3307/* Set the default SMTP code, and allow a user message to change it. */
a5bd321b 3308
4f6ae5c3
JH
3309smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451";
3310smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg,
3311 where != ACL_WHERE_VRFY);
a5bd321b 3312
059ec3d9
PH
3313/* We used to have sender_address here; however, there was a bug that was not
3314updating sender_address after a rewrite during a verify. When this bug was
3315fixed, sender_address at this point became the rewritten address. I'm not sure
3316this is what should be logged, so I've changed to logging the unrewritten
3317address to retain backward compatibility. */
3318
8523533c 3319#ifndef WITH_CONTENT_SCAN
059ec3d9 3320if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
8523533c
TK
3321#else
3322if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
3323#endif
059ec3d9 3324 {
b98bb9ac
PP
3325 sender_info = string_sprintf("F=<%s>%s%s%s%s ",
3326 sender_address_unrewritten ? sender_address_unrewritten : sender_address,
3327 sender_host_authenticated ? US" A=" : US"",
3328 sender_host_authenticated ? sender_host_authenticated : US"",
3329 sender_host_authenticated && authenticated_id ? US":" : US"",
3330 sender_host_authenticated && authenticated_id ? authenticated_id : US""
3331 );
059ec3d9
PH
3332 }
3333
3334/* If there's been a sender verification failure with a specific message, and
3335we have not sent a response about it yet, do so now, as a preliminary line for
278c6e6c
PH
3336failures, but not defers. However, always log it for defer, and log it for fail
3337unless the sender_verify_fail log selector has been turned off. */
059ec3d9 3338
02b41d71 3339if (sender_verified_failed &&
059ec3d9
PH
3340 !testflag(sender_verified_failed, af_sverify_told))
3341 {
88752192
JH
3342 BOOL save_rcpt_in_progress = fl.rcpt_in_progress;
3343 fl.rcpt_in_progress = FALSE; /* So as not to treat these as the error */
2679d413 3344
059ec3d9
PH
3345 setflag(sender_verified_failed, af_sverify_told);
3346
6c6d6e48 3347 if (rc != FAIL || LOGGING(sender_verify_fail))
278c6e6c
PH
3348 log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
3349 host_and_ident(TRUE),
3350 ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
3351 sender_verified_failed->address,
3352 (sender_verified_failed->message == NULL)? US"" :
3353 string_sprintf(": %s", sender_verified_failed->message));
059ec3d9 3354
02b41d71 3355 if (rc == FAIL && sender_verified_failed->user_message)
a5bd321b 3356 smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
059ec3d9
PH
3357 testflag(sender_verified_failed, af_verify_pmfail)?
3358 "Postmaster verification failed while checking <%s>\n%s\n"
3359 "Several RFCs state that you are required to have a postmaster\n"
3360 "mailbox for each mail domain. This host does not accept mail\n"
3361 "from domains whose servers reject the postmaster address."
3362 :
3363 testflag(sender_verified_failed, af_verify_nsfail)?
3364 "Callback setup failed while verifying <%s>\n%s\n"
3365 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
3366 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
3367 "RFC requirements, and stops you from receiving standard bounce\n"
3368 "messages. This host does not accept mail from domains whose servers\n"
3369 "refuse bounces."
3370 :
3371 "Verification failed for <%s>\n%s",
3372 sender_verified_failed->address,
3373 sender_verified_failed->user_message));
2679d413 3374
88752192 3375 fl.rcpt_in_progress = save_rcpt_in_progress;
059ec3d9
PH
3376 }
3377
3378/* Sort out text for logging */
3379
3cc3f762
JH
3380log_msg = log_msg ? string_sprintf(": %s", log_msg) : US"";
3381if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0;
059ec3d9
PH
3382
3383/* Send permanent failure response to the command, but the code used isn't
3384always a 5xx one - see comments at the start of this function. If the original
3385rc was FAIL_DROP we drop the connection and yield 2. */
3386
ff5929e3
JH
3387if (rc == FAIL)
3388 smtp_respond(smtp_code, codelen, TRUE,
3389 user_msg ? user_msg : US"Administrative prohibition");
059ec3d9
PH
3390
3391/* Send temporary failure response to the command. Don't give any details,
3392unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
3393verb, and for a header verify when smtp_return_error_details is set.
3394
3395This conditional logic is all somewhat of a mess because of the odd
3396interactions between temp_details and return_error_details. One day it should
3397be re-implemented in a tidier fashion. */
3398
3399else
8768d548 3400 if (f.acl_temp_details && user_msg)
059ec3d9 3401 {
ff5929e3
JH
3402 if ( smtp_return_error_details
3403 && sender_verified_failed
3404 && sender_verified_failed->message
3405 )
a5bd321b 3406 smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
ff5929e3 3407
a5bd321b 3408 smtp_respond(smtp_code, codelen, TRUE, user_msg);
059ec3d9
PH
3409 }
3410 else
a5bd321b
PH
3411 smtp_respond(smtp_code, codelen, TRUE,
3412 US"Temporary local problem - please try later");
059ec3d9 3413
6ea85e9a
PH
3414/* Log the incident to the logs that are specified by log_reject_target
3415(default main, reject). This can be empty to suppress logging of rejections. If
3416the connection is not forcibly to be dropped, return 0. Otherwise, log why it
3417is closing if required and return 2. */
059ec3d9 3418
6ea85e9a 3419if (log_reject_target != 0)
887291d2 3420 {
e45a1c37 3421#ifdef SUPPORT_TLS
acec9514
JH
3422 gstring * g = s_tlslog(NULL);
3423 uschar * tls = string_from_gstring(g);
fc16abb4 3424 if (!tls) tls = US"";
e45a1c37 3425#else
fc16abb4 3426 uschar * tls = US"";
e45a1c37 3427#endif
3cc3f762
JH
3428 log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0,
3429 log_reject_target, "%s%s%s %s%srejected %s%s",
fc16abb4
JH
3430 LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"",
3431 host_and_ident(TRUE),
3432 tls,
3433 sender_info,
3434 rc == FAIL ? US"" : US"temporarily ",
3435 what, log_msg);
887291d2 3436 }
059ec3d9
PH
3437
3438if (!drop) return 0;
3439
3440log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
3441 smtp_get_connection_info());
8f128379
PH
3442
3443/* Run the not-quit ACL, but without any custom messages. This should not be a
3444problem, because we get here only if some other ACL has issued "drop", and
3445in that case, *its* custom messages will have been used above. */
3446
3447smtp_notquit_exit(US"acl-drop", NULL, NULL);
059ec3d9
PH
3448return 2;
3449}
3450
3451
3452
3453
3454/*************************************************
8f128379
PH
3455* Handle SMTP exit when QUIT is not given *
3456*************************************************/
3457
3458/* This function provides a logging/statistics hook for when an SMTP connection
3459is dropped on the floor or the other end goes away. It's a global function
3460because it's called from receive.c as well as this module. As well as running
3461the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
3462response, either with a custom message from the ACL, or using a default. There
3463is one case, however, when no message is output - after "drop". In that case,
3464the ACL that obeyed "drop" has already supplied the custom message, and NULL is
3465passed to this function.
3466
3467In case things go wrong while processing this function, causing an error that
4c04137d 3468may re-enter this function, there is a recursion check.
8f128379
PH
3469
3470Arguments:
3471 reason What $smtp_notquit_reason will be set to in the ACL;
3472 if NULL, the ACL is not run
3473 code The error code to return as part of the response
3474 defaultrespond The default message if there's no user_msg
3475
3476Returns: Nothing
3477*/
3478
3479void
3480smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
3481{
3482int rc;
3483uschar *user_msg = NULL;
3484uschar *log_msg = NULL;
3485
3486/* Check for recursive acll */
3487
88752192 3488if (fl.smtp_exit_function_called)
8f128379
PH
3489 {
3490 log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
3491 reason);
3492 return;
3493 }
88752192 3494fl.smtp_exit_function_called = TRUE;
8f128379
PH
3495
3496/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
3497
eea0defe 3498if (acl_smtp_notquit && reason)
8f128379
PH
3499 {
3500 smtp_notquit_reason = reason;
eea0defe
JB
3501 if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
3502 &log_msg)) == ERROR)
8f128379
PH
3503 log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s",
3504 log_msg);
3505 }
3506
58c09a7f
JH
3507/* If the connection was dropped, we certainly are no longer talking TLS */
3508tls_in.active.sock = -1;
3509