Avoid leaving $domain live with bogus info, during server connection startup
[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{
d12746bc 916gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer };
fb08281f
DW
917BOOL yield;
918
d12746bc
JH
919yield = !! string_vformat(&gs, FALSE, format, ap);
920string_from_gstring(&gs);
ce552449 921
059ec3d9
PH
922DEBUG(D_receive)
923 {
fb08281f
DW
924 void *reset_point = store_get(0);
925 uschar *msg_copy, *cr, *end;
d12746bc
JH
926 msg_copy = string_copy(gs.s);
927 end = msg_copy + gs.ptr;
fb08281f 928 while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */
d12746bc 929 memmove(cr, cr + 1, (end--) - cr);
fb08281f
DW
930 debug_printf("SMTP>> %s", msg_copy);
931 store_reset(reset_point);
059ec3d9
PH
932 }
933
fb08281f 934if (!yield)
2679d413
PH
935 {
936 log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()");
937 smtp_closedown(US"Unexpected error");
9bfb7e1b 938 exim_exit(EXIT_FAILURE, NULL);
2679d413 939 }
2679d413
PH
940
941/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
942have had the same. Note: this code is also present in smtp_respond(). It would
943be tidier to have it only in one place, but when it was added, it was easier to
944do it that way, so as not to have to mess with the code for the RCPT command,
945which sometimes uses smtp_printf() and sometimes smtp_respond(). */
946
88752192 947if (fl.rcpt_in_progress)
2679d413
PH
948 {
949 if (rcpt_smtp_response == NULL)
950 rcpt_smtp_response = string_copy(big_buffer);
88752192 951 else if (fl.rcpt_smtp_response_same &&
2679d413 952 Ustrcmp(rcpt_smtp_response, big_buffer) != 0)
88752192
JH
953 fl.rcpt_smtp_response_same = FALSE;
954 fl.rcpt_in_progress = FALSE;
2679d413 955 }
059ec3d9 956
2679d413 957/* Now write the string */
059ec3d9
PH
958
959#ifdef SUPPORT_TLS
74f1a423 960if (tls_in.active.sock >= 0)
059ec3d9 961 {
d12746bc 962 if (tls_write(NULL, gs.s, gs.ptr, more) < 0)
817d9f57 963 smtp_write_error = -1;
059ec3d9
PH
964 }
965else
966#endif
967
d12746bc 968if (fprintf(smtp_out, "%s", gs.s) < 0) smtp_write_error = -1;
059ec3d9
PH
969}
970
971
972
973/*************************************************
974* Flush SMTP out and check for error *
975*************************************************/
976
977/* This function isn't currently used within Exim (it detects errors when it
978tries to read the next SMTP input), but is available for use in local_scan().
979For non-TLS connections, it flushes the output and checks for errors. For
980TLS-connections, it checks for a previously-detected TLS write error.
981
982Arguments: none
983Returns: 0 for no error; -1 after an error
984*/
985
986int
987smtp_fflush(void)
988{
74f1a423 989if (tls_in.active.sock < 0 && fflush(smtp_out) != 0) smtp_write_error = -1;
059ec3d9
PH
990return smtp_write_error;
991}
992
993
994
995/*************************************************
996* SMTP command read timeout *
997*************************************************/
998
999/* Signal handler for timing out incoming SMTP commands. This attempts to
1000finish off tidily.
1001
1002Argument: signal number (SIGALRM)
1003Returns: nothing
1004*/
1005
1006static void
1007command_timeout_handler(int sig)
1008{
9723f966 1009had_command_timeout = sig;
059ec3d9
PH
1010}
1011
1012
1013
1014/*************************************************
1015* SIGTERM received *
1016*************************************************/
1017
1018/* Signal handler for handling SIGTERM. Again, try to finish tidily.
1019
1020Argument: signal number (SIGTERM)
1021Returns: nothing
1022*/
1023
1024static void
1025command_sigterm_handler(int sig)
1026{
9723f966 1027had_command_sigterm = sig;
059ec3d9
PH
1028}
1029
1030
1031
a14e5636 1032
cee5f132 1033#ifdef SUPPORT_PROXY
a3c86431 1034/*************************************************
a3bddaa8
TL
1035* Restore socket timeout to previous value *
1036*************************************************/
1037/* If the previous value was successfully retrieved, restore
1038it before returning control to the non-proxy routines
1039
1040Arguments: fd - File descriptor for input
1041 get_ok - Successfully retrieved previous values
1042 tvtmp - Time struct with previous values
1043 vslen - Length of time struct
1044Returns: none
1045*/
1046static void
f267271d 1047restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen)
a3bddaa8
TL
1048{
1049if (get_ok == 0)
f267271d 1050 (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen);
a3bddaa8
TL
1051}
1052
1053/*************************************************
a3c86431
TL
1054* Check if host is required proxy host *
1055*************************************************/
1056/* The function determines if inbound host will be a regular smtp host
1811cb4c
JH
1057or if it is configured that it must use Proxy Protocol. A local
1058connection cannot.
a3c86431
TL
1059
1060Arguments: none
1061Returns: bool
1062*/
1063
1064static BOOL
1065check_proxy_protocol_host()
1066{
1067int rc;
a3c86431 1068
1811cb4c
JH
1069if ( sender_host_address
1070 && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL,
1071 sender_host_address, NULL)) == OK)
a3c86431
TL
1072 {
1073 DEBUG(D_receive)
1074 debug_printf("Detected proxy protocol configured host\n");
1075 proxy_session = TRUE;
1076 }
1077return proxy_session;
1078}
1079
1080
1081/*************************************************
3f251b3c
PP
1082* Read data until newline or end of buffer *
1083*************************************************/
1084/* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't
1085read an entire buffer and assume there will be nothing past a proxy protocol
1086header. Our approach normally is to use stdio, but again that relies upon
1087"STARTTLS\r\n" and a server response before the client starts TLS handshake, or
1088reading _nothing_ before client TLS handshake. So we don't want to use the
1089usual buffering reads which may read enough to block TLS starting.
1090
1091So unfortunately we're down to "read one byte at a time, with a syscall each,
1092and expect a little overhead", for all proxy-opened connections which are v1,
1093just to handle the TLS-on-connect case. Since SSL functions wrap the
1094underlying fd, we can't assume that we can feed them any already-read content.
1095
1096We need to know where to read to, the max capacity, and we'll read until we
1097get a CR and one more character. Let the caller scream if it's CR+!LF.
1098
1099Return the amount read.
1100*/
1101
1102static int
da88acae 1103swallow_until_crlf(int fd, uschar *base, int already, int capacity)
3f251b3c 1104{
2c0f3ea1
JH
1105uschar *to = base + already;
1106uschar *cr;
1107int have = 0;
1108int ret;
1109int last = 0;
1110
1111/* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read
1112up through the \r; for the _normal_ case, we haven't yet seen the \r. */
da88acae 1113
2c0f3ea1
JH
1114cr = memchr(base, '\r', already);
1115if (cr != NULL)
1116 {
1117 if ((cr - base) < already - 1)
da88acae 1118 {
2c0f3ea1
JH
1119 /* \r and presumed \n already within what we have; probably not
1120 actually proxy protocol, but abort cleanly. */
1121 return 0;
da88acae 1122 }
2c0f3ea1
JH
1123 /* \r is last character read, just need one more. */
1124 last = 1;
1125 }
1126
1127while (capacity > 0)
1128 {
1129 do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR);
1130 if (ret == -1)
1131 return -1;
1132 have++;
1133 if (last)
1134 return have;
1135 if (*to == '\r')
1136 last = 1;
1137 capacity--;
1138 to++;
1139 }
1140
1141/* reached end without having room for a final newline, abort */
1142errno = EOVERFLOW;
1143return -1;
3f251b3c
PP
1144}
1145
1146/*************************************************
a3c86431
TL
1147* Setup host for proxy protocol *
1148*************************************************/
1149/* The function configures the connection based on a header from the
1150inbound host to use Proxy Protocol. The specification is very exact
1151so exit with an error if do not find the exact required pieces. This
1152includes an incorrect number of spaces separating args.
1153
1154Arguments: none
f267271d 1155Returns: Boolean success
a3c86431
TL
1156*/
1157
1811cb4c 1158static void
a3c86431
TL
1159setup_proxy_protocol_host()
1160{
1161union {
1162 struct {
1163 uschar line[108];
1164 } v1;
1165 struct {
1166 uschar sig[12];
36719342
TL
1167 uint8_t ver_cmd;
1168 uint8_t fam;
1169 uint16_t len;
a3c86431
TL
1170 union {
1171 struct { /* TCP/UDP over IPv4, len = 12 */
1172 uint32_t src_addr;
1173 uint32_t dst_addr;
1174 uint16_t src_port;
1175 uint16_t dst_port;
1176 } ip4;
1177 struct { /* TCP/UDP over IPv6, len = 36 */
1178 uint8_t src_addr[16];
1179 uint8_t dst_addr[16];
1180 uint16_t src_port;
1181 uint16_t dst_port;
1182 } ip6;
1183 struct { /* AF_UNIX sockets, len = 216 */
1184 uschar src_addr[108];
1185 uschar dst_addr[108];
1186 } unx;
1187 } addr;
1188 } v2;
1189} hdr;
1190
eb57651e
TL
1191/* Temp variables used in PPv2 address:port parsing */
1192uint16_t tmpport;
1193char tmpip[INET_ADDRSTRLEN];
1194struct sockaddr_in tmpaddr;
1195char tmpip6[INET6_ADDRSTRLEN];
1196struct sockaddr_in6 tmpaddr6;
1197
da88acae
PP
1198/* We can't read "all data until end" because while SMTP is
1199server-speaks-first, the TLS handshake is client-speaks-first, so for
1200TLS-on-connect ports the proxy protocol header will usually be immediately
1201followed by a TLS handshake, and with N TLS libraries, we can't reliably
1202reinject data for reading by those. So instead we first read "enough to be
1203safely read within the header, and figure out how much more to read".
1204For v1 we will later read to the end-of-line, for v2 we will read based upon
1205the stated length.
1206
1207The v2 sig is 12 octets, and another 4 gets us the length, so we know how much
1208data is needed total. For v1, where the line looks like:
1209PROXY TCPn L3src L3dest SrcPort DestPort \r\n
1210
1211However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets.
1212We seem to support that. So, if we read 14 octets then we can tell if we're
1213v2 or v1. If we're v1, we can continue reading as normal.
1214
1215If we're v2, we can't slurp up the entire header. We need the length in the
121615th & 16th octets, then to read everything after that.
1217
1218So to safely handle v1 and v2, with client-sent-first supported correctly,
1219we have to do a minimum of 3 read calls, not 1. Eww.
1220*/
1221
1222#define PROXY_INITIAL_READ 14
1223#define PROXY_V2_HEADER_SIZE 16
1224#if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE
1225# error Code bug in sizes of data to read for proxy usage
1226#endif
1227
eb57651e 1228int get_ok = 0;
f267271d
JH
1229int size, ret;
1230int fd = fileno(smtp_in);
36719342 1231const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
9e7e0f6a 1232uschar * iptype; /* To display debug info */
a3c86431 1233struct timeval tv;
a3bddaa8 1234struct timeval tvtmp;
f267271d 1235socklen_t vslen = sizeof(struct timeval);
1811cb4c 1236BOOL yield = FALSE;
a3c86431 1237
a3bddaa8 1238/* Save current socket timeout values */
f267271d 1239get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen);
a3bddaa8 1240
a3c86431
TL
1241/* Proxy Protocol host must send header within a short time
1242(default 3 seconds) or it's considered invalid */
1243tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC;
1244tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC;
f267271d 1245if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0)
1811cb4c 1246 goto bad;
a3bddaa8 1247
a3c86431
TL
1248do
1249 {
eb57651e 1250 /* The inbound host was declared to be a Proxy Protocol host, so
2c0f3ea1
JH
1251 don't do a PEEK into the data, actually slurp up enough to be
1252 "safe". Can't take it all because TLS-on-connect clients follow
1253 immediately with TLS handshake. */
3f251b3c 1254 ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0);
a3c86431
TL
1255 }
1256 while (ret == -1 && errno == EINTR);
1257
1258if (ret == -1)
f267271d 1259 goto proxyfail;
a3c86431 1260
da88acae
PP
1261/* For v2, handle reading the length, and then the rest. */
1262if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0))
a3c86431 1263 {
da88acae
PP
1264 int retmore;
1265 uint8_t ver;
1266
1267 /* First get the length fields. */
1268 do
1269 {
1270 retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0);
1271 } while (retmore == -1 && errno == EINTR);
1272 if (retmore == -1)
3f251b3c 1273 goto proxyfail;
da88acae 1274 ret += retmore;
3f251b3c
PP
1275
1276 ver = (hdr.v2.ver_cmd & 0xf0) >> 4;
36719342
TL
1277
1278 /* May 2014: haproxy combined the version and command into one byte to
2c0f3ea1
JH
1279 allow two full bytes for the length field in order to proxy SSL
1280 connections. SSL Proxy is not supported in this version of Exim, but
1281 must still separate values here. */
36719342
TL
1282
1283 if (ver != 0x02)
1284 {
1285 DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver);
1286 goto proxyfail;
1287 }
da88acae 1288
36719342 1289 /* The v2 header will always be 16 bytes per the spec. */
5d036699 1290 size = 16 + ntohs(hdr.v2.len);
da88acae
PP
1291 DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n",
1292 size, (int)sizeof(hdr));
1293
1294 /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total
1295 amount that we need. Double-check that the size is not unreasonable, then
1296 get the rest. */
1297 if (size > sizeof(hdr))
a3c86431 1298 {
da88acae 1299 DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n");
a3c86431
TL
1300 goto proxyfail;
1301 }
da88acae
PP
1302
1303 do
1304 {
1305 do
1306 {
1307 retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0);
1308 } while (retmore == -1 && errno == EINTR);
1309 if (retmore == -1)
1310 goto proxyfail;
1311 ret += retmore;
1312 DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size);
1313 } while (ret < size);
1314
1315 } /* end scope for getting rest of data for v2 */
1316
1317/* At this point: if PROXYv2, we've read the exact size required for all data;
1318if PROXYv1 then we've read "less than required for any valid line" and should
1319read the rest". */
1320
1321if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0)
1322 {
1323 uint8_t cmd = (hdr.v2.ver_cmd & 0x0f);
1324
36719342 1325 switch (cmd)
a3c86431
TL
1326 {
1327 case 0x01: /* PROXY command */
1328 switch (hdr.v2.fam)
1329 {
eb57651e
TL
1330 case 0x11: /* TCPv4 address type */
1331 iptype = US"IPv4";
1332 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr;
5d036699
JH
1333 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1334 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1335 {
1336 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1337 goto proxyfail;
eb57651e 1338 }
e6d2a989 1339 proxy_local_address = sender_host_address;
eb57651e
TL
1340 sender_host_address = string_copy(US tmpip);
1341 tmpport = ntohs(hdr.v2.addr.ip4.src_port);
e6d2a989 1342 proxy_local_port = sender_host_port;
eb57651e
TL
1343 sender_host_port = tmpport;
1344 /* Save dest ip/port */
1345 tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr;
5d036699
JH
1346 inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip));
1347 if (!string_is_ip_address(US tmpip, NULL))
eb57651e
TL
1348 {
1349 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1350 goto proxyfail;
eb57651e 1351 }
7a2fa0bc 1352 proxy_external_address = string_copy(US tmpip);
eb57651e 1353 tmpport = ntohs(hdr.v2.addr.ip4.dst_port);
7a2fa0bc 1354 proxy_external_port = tmpport;
a3c86431 1355 goto done;
eb57651e
TL
1356 case 0x21: /* TCPv6 address type */
1357 iptype = US"IPv6";
1358 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16);
5d036699
JH
1359 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1360 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1361 {
1362 DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype);
f267271d 1363 goto proxyfail;
eb57651e 1364 }
e6d2a989 1365 proxy_local_address = sender_host_address;
eb57651e
TL
1366 sender_host_address = string_copy(US tmpip6);
1367 tmpport = ntohs(hdr.v2.addr.ip6.src_port);
e6d2a989 1368 proxy_local_port = sender_host_port;
eb57651e
TL
1369 sender_host_port = tmpport;
1370 /* Save dest ip/port */
1371 memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16);
5d036699
JH
1372 inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6));
1373 if (!string_is_ip_address(US tmpip6, NULL))
eb57651e
TL
1374 {
1375 DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype);
f267271d 1376 goto proxyfail;
eb57651e 1377 }
7a2fa0bc 1378 proxy_external_address = string_copy(US tmpip6);
eb57651e 1379 tmpport = ntohs(hdr.v2.addr.ip6.dst_port);
7a2fa0bc 1380 proxy_external_port = tmpport;
a3c86431 1381 goto done;
eb57651e
TL
1382 default:
1383 DEBUG(D_receive)
1384 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
1385 hdr.v2.fam);
1386 goto proxyfail;
a3c86431
TL
1387 }
1388 /* Unsupported protocol, keep local connection address */
1389 break;
1390 case 0x00: /* LOCAL command */
1391 /* Keep local connection address for LOCAL */
9e7e0f6a 1392 iptype = US"local";
a3c86431
TL
1393 break;
1394 default:
eb57651e 1395 DEBUG(D_receive)
36719342 1396 debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd);
a3c86431
TL
1397 goto proxyfail;
1398 }
1399 }
5d036699 1400else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0)
a3c86431 1401 {
3f251b3c
PP
1402 uschar *p;
1403 uschar *end;
a3c86431
TL
1404 uschar *sp; /* Utility variables follow */
1405 int tmp_port;
3f251b3c 1406 int r2;
a3c86431
TL
1407 char *endc;
1408
3f251b3c 1409 /* get the rest of the line */
da88acae 1410 r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
3f251b3c
PP
1411 if (r2 == -1)
1412 goto proxyfail;
1413 ret += r2;
1414
1415 p = string_copy(hdr.v1.line);
1416 end = memchr(p, '\r', ret - 1);
1417
da88acae 1418 if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n')
a3c86431
TL
1419 {
1420 DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n");
1421 goto proxyfail;
1422 }
1423 *end = '\0'; /* Terminate the string */
a5d4db40 1424 size = end + 2 - p; /* Skip header + CRLF */
a3c86431 1425 DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n");
3f251b3c 1426 DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size);
a3c86431 1427 /* Step through the string looking for the required fields. Ensure
2c0f3ea1 1428 strict adherence to required formatting, exit for any error. */
a3c86431
TL
1429 p += 5;
1430 if (!isspace(*(p++)))
1431 {
1432 DEBUG(D_receive) debug_printf("Missing space after PROXY command\n");
1433 goto proxyfail;
1434 }
1435 if (!Ustrncmp(p, CCS"TCP4", 4))
1436 iptype = US"IPv4";
1437 else if (!Ustrncmp(p,CCS"TCP6", 4))
1438 iptype = US"IPv6";
1439 else if (!Ustrncmp(p,CCS"UNKNOWN", 7))
1440 {
1441 iptype = US"Unknown";
1442 goto done;
1443 }
1444 else
1445 {
1446 DEBUG(D_receive) debug_printf("Invalid TCP type\n");
1447 goto proxyfail;
1448 }
1449
1450 p += Ustrlen(iptype);
1451 if (!isspace(*(p++)))
1452 {
1453 DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n");
1454 goto proxyfail;
1455 }
1456 /* Find the end of the arg */
1457 if ((sp = Ustrchr(p, ' ')) == NULL)
1458 {
1459 DEBUG(D_receive)
1460 debug_printf("Did not find proxied src %s\n", iptype);
1461 goto proxyfail;
1462 }
1463 *sp = '\0';
5d036699 1464 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1465 {
1466 DEBUG(D_receive)
1467 debug_printf("Proxied src arg is not an %s address\n", iptype);
1468 goto proxyfail;
1469 }
e6d2a989 1470 proxy_local_address = sender_host_address;
a3c86431
TL
1471 sender_host_address = p;
1472 p = sp + 1;
1473 if ((sp = Ustrchr(p, ' ')) == NULL)
1474 {
1475 DEBUG(D_receive)
1476 debug_printf("Did not find proxy dest %s\n", iptype);
1477 goto proxyfail;
1478 }
1479 *sp = '\0';
5d036699 1480 if(!string_is_ip_address(p, NULL))
a3c86431
TL
1481 {
1482 DEBUG(D_receive)
1483 debug_printf("Proxy dest arg is not an %s address\n", iptype);
1484 goto proxyfail;
1485 }
7a2fa0bc 1486 proxy_external_address = p;
a3c86431
TL
1487 p = sp + 1;
1488 if ((sp = Ustrchr(p, ' ')) == NULL)
1489 {
1490 DEBUG(D_receive) debug_printf("Did not find proxied src port\n");
1491 goto proxyfail;
1492 }
1493 *sp = '\0';
5d036699 1494 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1495 if (*endc || tmp_port == 0)
1496 {
1497 DEBUG(D_receive)
1498 debug_printf("Proxied src port '%s' not an integer\n", p);
1499 goto proxyfail;
1500 }
e6d2a989 1501 proxy_local_port = sender_host_port;
a3c86431
TL
1502 sender_host_port = tmp_port;
1503 p = sp + 1;
1504 if ((sp = Ustrchr(p, '\0')) == NULL)
1505 {
1506 DEBUG(D_receive) debug_printf("Did not find proxy dest port\n");
1507 goto proxyfail;
1508 }
5d036699 1509 tmp_port = strtol(CCS p, &endc, 10);
a3c86431
TL
1510 if (*endc || tmp_port == 0)
1511 {
1512 DEBUG(D_receive)
1513 debug_printf("Proxy dest port '%s' not an integer\n", p);
1514 goto proxyfail;
1515 }
7a2fa0bc 1516 proxy_external_port = tmp_port;
a3c86431 1517 /* Already checked for /r /n above. Good V1 header received. */
a3c86431
TL
1518 }
1519else
1520 {
1521 /* Wrong protocol */
eb57651e 1522 DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n");
da88acae 1523 (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret);
a3c86431
TL
1524 goto proxyfail;
1525 }
1526
1811cb4c
JH
1527done:
1528 DEBUG(D_receive)
1529 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype);
1530 yield = proxy_session;
1531
1532/* Don't flush any potential buffer contents. Any input on proxyfail
1533should cause a synchronization failure */
1534
a3c86431 1535proxyfail:
1811cb4c 1536 restore_socket_timeout(fd, get_ok, &tvtmp, vslen);
a3c86431 1537
1811cb4c
JH
1538bad:
1539 if (yield)
1540 {
1541 sender_host_name = NULL;
1542 (void) host_name_lookup();
1543 host_build_sender_fullhost();
1544 }
1545 else
1546 {
8768d548 1547 f.proxy_session_failed = TRUE;
1811cb4c
JH
1548 DEBUG(D_receive)
1549 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
1550 }
1551
1552return;
a3c86431
TL
1553}
1554#endif
1555
059ec3d9
PH
1556/*************************************************
1557* Read one command line *
1558*************************************************/
1559
1560/* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
1561There are sites that don't do this, and in any case internal SMTP probably
1562should check only for LF. Consequently, we check here for LF only. The line
1563ends up with [CR]LF removed from its end. If we get an overlong line, treat as
3ee512ff
PH
1564an unknown command. The command is read into the global smtp_cmd_buffer so that
1565it is available via $smtp_command.
059ec3d9
PH
1566
1567The character reading routine sets up a timeout for each block actually read
1568from the input (which may contain more than one command). We set up a special
1569signal handler that closes down the session on a timeout. Control does not
1570return when it runs.
1571
1572Arguments:
bd8fbe36
JH
1573 check_sync if TRUE, check synchronization rules if global option is TRUE
1574 buffer_lim maximum to buffer in lower layer
059ec3d9
PH
1575
1576Returns: a code identifying the command (enumerated above)
1577*/
1578
1579static int
bd8fbe36 1580smtp_read_command(BOOL check_sync, unsigned buffer_lim)
059ec3d9
PH
1581{
1582int c;
1583int ptr = 0;
1584smtp_cmd_list *p;
1585BOOL hadnull = FALSE;
1586
9723f966 1587had_command_timeout = 0;
059ec3d9
PH
1588os_non_restarting_signal(SIGALRM, command_timeout_handler);
1589
bd8fbe36 1590while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF)
059ec3d9 1591 {
bd8fbe36 1592 if (ptr >= SMTP_CMD_BUFFER_SIZE)
059ec3d9
PH
1593 {
1594 os_non_restarting_signal(SIGALRM, sigalrm_handler);
1595 return OTHER_CMD;
1596 }
1597 if (c == 0)
1598 {
1599 hadnull = TRUE;
1600 c = '?';
1601 }
3ee512ff 1602 smtp_cmd_buffer[ptr++] = c;
059ec3d9
PH
1603 }
1604
1605receive_linecount++; /* For BSMTP errors */
1606os_non_restarting_signal(SIGALRM, sigalrm_handler);
1607
1608/* If hit end of file, return pseudo EOF command. Whether we have a
1609part-line already read doesn't matter, since this is an error state. */
1610
1611if (c == EOF) return EOF_CMD;
1612
1613/* Remove any CR and white space at the end of the line, and terminate the
1614string. */
1615
3ee512ff
PH
1616while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--;
1617smtp_cmd_buffer[ptr] = 0;
059ec3d9 1618
3ee512ff 1619DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer);
059ec3d9
PH
1620
1621/* NULLs are not allowed in SMTP commands */
1622
1623if (hadnull) return BADCHAR_CMD;
1624
1625/* Scan command list and return identity, having set the data pointer
1626to the start of the actual data characters. Check for SMTP synchronization
1627if required. */
1628
1629for (p = cmd_list; p < cmd_list_end; p++)
1630 {
1811cb4c 1631#ifdef SUPPORT_PROXY
a3c86431 1632 /* Only allow QUIT command if Proxy Protocol parsing failed */
8768d548 1633 if (proxy_session && f.proxy_session_failed && p->cmd != QUIT_CMD)
1811cb4c
JH
1634 continue;
1635#endif
2f460950
JH
1636 if ( p->len
1637 && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0
1638 && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */
1639 || smtp_cmd_buffer[p->len] == 0
1640 || smtp_cmd_buffer[p->len] == ' '
1641 ) )
059ec3d9
PH
1642 {
1643 if (smtp_inptr < smtp_inend && /* Outstanding input */
1644 p->cmd < sync_cmd_limit && /* Command should sync */
1645 check_sync && /* Local flag set */
1646 smtp_enforce_sync && /* Global flag set */
1647 sender_host_address != NULL && /* Not local input */
8768d548 1648 !f.sender_host_notsocket) /* Really is a socket */
059ec3d9
PH
1649 return BADSYN_CMD;
1650
ca86f471
PH
1651 /* The variables $smtp_command and $smtp_command_argument point into the
1652 unmodified input buffer. A copy of the latter is taken for actual
1653 processing, so that it can be chopped up into separate parts if necessary,
1654 for example, when processing a MAIL command options such as SIZE that can
1655 follow the sender address. */
059ec3d9 1656
3ee512ff 1657 smtp_cmd_argument = smtp_cmd_buffer + p->len;
ca86f471
PH
1658 while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++;
1659 Ustrcpy(smtp_data_buffer, smtp_cmd_argument);
1660 smtp_cmd_data = smtp_data_buffer;
059ec3d9
PH
1661
1662 /* Count non-mail commands from those hosts that are controlled in this
1663 way. The default is all hosts. We don't waste effort checking the list
1664 until we get a non-mail command, but then cache the result to save checking
1665 again. If there's a DEFER while checking the host, assume it's in the list.
1666
1667 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1668 start of each incoming message by fiddling with the value in the table. */
1669
1670 if (!p->is_mail_cmd)
1671 {
1672 if (count_nonmail == TRUE_UNSET) count_nonmail =
1673 verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL;
1674 if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail)
1675 return TOO_MANY_NONMAIL_CMD;
1676 }
1677
ca86f471
PH
1678 /* If there is data for a command that does not expect it, generate the
1679 error here. */
059ec3d9 1680
ca86f471 1681 return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD;
059ec3d9
PH
1682 }
1683 }
1684
cee5f132 1685#ifdef SUPPORT_PROXY
a3c86431 1686/* Only allow QUIT command if Proxy Protocol parsing failed */
8768d548 1687if (proxy_session && f.proxy_session_failed)
a3c86431
TL
1688 return PROXY_FAIL_IGNORE_CMD;
1689#endif
1690
059ec3d9
PH
1691/* Enforce synchronization for unknown commands */
1692
ecce6d9a
JH
1693if ( smtp_inptr < smtp_inend /* Outstanding input */
1694 && check_sync /* Local flag set */
1695 && smtp_enforce_sync /* Global flag set */
1696 && sender_host_address /* Not local input */
8768d548 1697 && !f.sender_host_notsocket) /* Really is a socket */
059ec3d9
PH
1698 return BADSYN_CMD;
1699
1700return OTHER_CMD;
1701}
1702
1703
1704
1705/*************************************************
1706* Forced closedown of call *
1707*************************************************/
1708
1709/* This function is called from log.c when Exim is dying because of a serious
1710disaster, and also from some other places. If an incoming non-batched SMTP
1711channel is open, it swallows the rest of the incoming message if in the DATA
1712phase, sends the reply string, and gives an error to all subsequent commands
1713except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1714smtp_in.
1715
8f128379
PH
1716Arguments:
1717 message SMTP reply string to send, excluding the code
1718
059ec3d9
PH
1719Returns: nothing
1720*/
1721
1722void
1723smtp_closedown(uschar *message)
1724{
db57e575 1725if (!smtp_in || smtp_batched_input) return;
059ec3d9 1726receive_swallow_smtp();
925ac8e4 1727smtp_printf("421 %s\r\n", FALSE, message);
059ec3d9 1728
bd8fbe36 1729for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9 1730 {
60d10ce7 1731 case EOF_CMD:
db57e575 1732 return;
059ec3d9 1733
60d10ce7 1734 case QUIT_CMD:
db57e575
JH
1735 smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname);
1736 mac_smtp_fflush();
1737 return;
059ec3d9 1738
60d10ce7 1739 case RSET_CMD:
db57e575
JH
1740 smtp_printf("250 Reset OK\r\n", FALSE);
1741 break;
059ec3d9 1742
60d10ce7 1743 default:
db57e575
JH
1744 smtp_printf("421 %s\r\n", FALSE, message);
1745 break;
059ec3d9
PH
1746 }
1747}
1748
1749
1750
1751
1752/*************************************************
1753* Set up connection info for logging *
1754*************************************************/
1755
1756/* This function is called when logging information about an SMTP connection.
1757It sets up appropriate source information, depending on the type of connection.
dac79d3e
PH
1758If sender_fullhost is NULL, we are at a very early stage of the connection;
1759just use the IP address.
059ec3d9
PH
1760
1761Argument: none
1762Returns: a string describing the connection
1763*/
1764
1765uschar *
1766smtp_get_connection_info(void)
1767{
f5d25c2b
JH
1768const uschar * hostname = sender_fullhost
1769 ? sender_fullhost : sender_host_address;
dac79d3e 1770
059ec3d9 1771if (host_checking)
dac79d3e 1772 return string_sprintf("SMTP connection from %s", hostname);
059ec3d9 1773
8768d548 1774if (f.sender_host_unknown || f.sender_host_notsocket)
059ec3d9
PH
1775 return string_sprintf("SMTP connection from %s", sender_ident);
1776
8768d548 1777if (f.is_inetd)
dac79d3e 1778 return string_sprintf("SMTP connection from %s (via inetd)", hostname);
059ec3d9 1779
52f12a7c 1780if (LOGGING(incoming_interface) && interface_address)
dac79d3e 1781 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname,
059ec3d9
PH
1782 interface_address, interface_port);
1783
dac79d3e 1784return string_sprintf("SMTP connection from %s", hostname);
059ec3d9
PH
1785}
1786
1787
1788
e45a1c37 1789#ifdef SUPPORT_TLS
887291d2
JH
1790/* Append TLS-related information to a log line
1791
1792Arguments:
acec9514 1793 g String under construction: allocated string to extend, or NULL
887291d2
JH
1794
1795Returns: Allocated string or NULL
1796*/
acec9514
JH
1797static gstring *
1798s_tlslog(gstring * g)
e45a1c37 1799{
acec9514
JH
1800if (LOGGING(tls_cipher) && tls_in.cipher)
1801 g = string_append(g, 2, US" X=", tls_in.cipher);
1802if (LOGGING(tls_certificate_verified) && tls_in.cipher)
1803 g = string_append(g, 2, US" CV=", tls_in.certificate_verified? "yes":"no");
1804if (LOGGING(tls_peerdn) && tls_in.peerdn)
1805 g = string_append(g, 3, US" DN=\"", string_printing(tls_in.peerdn), US"\"");
1806if (LOGGING(tls_sni) && tls_in.sni)
1807 g = string_append(g, 3, US" SNI=\"", string_printing(tls_in.sni), US"\"");
1808return g;
e45a1c37
JH
1809}
1810#endif
1811
059ec3d9 1812/*************************************************
b4ed4da0
PH
1813* Log lack of MAIL if so configured *
1814*************************************************/
1815
1816/* This function is called when an SMTP session ends. If the log selector
1817smtp_no_mail is set, write a log line giving some details of what has happened
1818in the SMTP session.
1819
1820Arguments: none
1821Returns: nothing
1822*/
1823
1824void
1825smtp_log_no_mail(void)
1826{
acec9514
JH
1827int i;
1828uschar * sep, * s;
1829gstring * g = NULL;
b4ed4da0 1830
6c6d6e48 1831if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail))
b4ed4da0
PH
1832 return;
1833
db57e575 1834if (sender_host_authenticated)
b4ed4da0 1835 {
acec9514
JH
1836 g = string_append(g, 2, US" A=", sender_host_authenticated);
1837 if (authenticated_id) g = string_append(g, 2, US":", authenticated_id);
b4ed4da0
PH
1838 }
1839
1840#ifdef SUPPORT_TLS
acec9514 1841g = s_tlslog(g);
3f0945ff 1842#endif
b4ed4da0 1843
acec9514
JH
1844sep = smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE ? US" C=..." : US" C=";
1845
b4ed4da0 1846for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
b4ed4da0
PH
1847 if (smtp_connection_had[i] != SCH_NONE)
1848 {
acec9514 1849 g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
b4ed4da0
PH
1850 sep = US",";
1851 }
b4ed4da0
PH
1852
1853for (i = 0; i < smtp_ch_index; i++)
1854 {
acec9514 1855 g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]);
b4ed4da0
PH
1856 sep = US",";
1857 }
1858
acec9514
JH
1859if (!(s = string_from_gstring(g))) s = US"";
1860
a2673768 1861log_write(0, LOG_MAIN, "no MAIL in %sSMTP connection from %s D=%s%s",
ee8b8090 1862 f.tcp_in_fastopen ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO " : US"",
0f1a8658 1863 host_and_ident(FALSE), string_timesince(&smtp_connection_start), s);
b4ed4da0
PH
1864}
1865
1866
a09f2942
JH
1867/* Return list of recent smtp commands */
1868
1869uschar *
1870smtp_cmd_hist(void)
1871{
acec9514
JH
1872int i;
1873gstring * list = NULL;
1874uschar * s;
a09f2942
JH
1875
1876for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++)
1877 if (smtp_connection_had[i] != SCH_NONE)
acec9514
JH
1878 list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
1879
a09f2942 1880for (i = 0; i < smtp_ch_index; i++)
acec9514
JH
1881 list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]);
1882
1883s = string_from_gstring(list);
1884return s ? s : US"";
a09f2942
JH
1885}
1886
1887
1888
b4ed4da0
PH
1889
1890/*************************************************
059ec3d9
PH
1891* Check HELO line and set sender_helo_name *
1892*************************************************/
1893
1894/* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1895the domain name of the sending host, or an ip literal in square brackets. The
4c04137d 1896argument is placed in sender_helo_name, which is in malloc store, because it
059ec3d9
PH
1897must persist over multiple incoming messages. If helo_accept_junk is set, this
1898host is permitted to send any old junk (needed for some broken hosts).
1899Otherwise, helo_allow_chars can be used for rogue characters in general
1900(typically people want to let in underscores).
1901
1902Argument:
1903 s the data portion of the line (already past any white space)
1904
1905Returns: TRUE or FALSE
1906*/
1907
1908static BOOL
1909check_helo(uschar *s)
1910{
1911uschar *start = s;
1912uschar *end = s + Ustrlen(s);
88752192 1913BOOL yield = fl.helo_accept_junk;
059ec3d9
PH
1914
1915/* Discard any previous helo name */
1916
2d0dc929 1917if (sender_helo_name)
059ec3d9
PH
1918 {
1919 store_free(sender_helo_name);
1920 sender_helo_name = NULL;
1921 }
1922
1923/* Skip tests if junk is permitted. */
1924
1925if (!yield)
db57e575 1926
059ec3d9
PH
1927 /* Allow the new standard form for IPv6 address literals, namely,
1928 [IPv6:....], and because someone is bound to use it, allow an equivalent
1929 IPv4 form. Allow plain addresses as well. */
1930
1931 if (*s == '[')
1932 {
1933 if (end[-1] == ']')
1934 {
1935 end[-1] = 0;
1936 if (strncmpic(s, US"[IPv6:", 6) == 0)
1937 yield = (string_is_ip_address(s+6, NULL) == 6);
1938 else if (strncmpic(s, US"[IPv4:", 6) == 0)
1939 yield = (string_is_ip_address(s+6, NULL) == 4);
1940 else
1941 yield = (string_is_ip_address(s+1, NULL) != 0);
1942 end[-1] = ']';
1943 }
1944 }
1945
1946 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1947 that have been configured (usually underscore - sigh). */
1948
db57e575
JH
1949 else if (*s)
1950 for (yield = TRUE; *s; s++)
059ec3d9
PH
1951 if (!isalnum(*s) && *s != '.' && *s != '-' &&
1952 Ustrchr(helo_allow_chars, *s) == NULL)
1953 {
1954 yield = FALSE;
1955 break;
1956 }
059ec3d9
PH
1957
1958/* Save argument if OK */
1959
1960if (yield) sender_helo_name = string_copy_malloc(start);
1961return yield;
1962}
1963
1964
1965
1966
1967
1968/*************************************************
1969* Extract SMTP command option *
1970*************************************************/
1971
ca86f471 1972/* This function picks the next option setting off the end of smtp_cmd_data. It
059ec3d9
PH
1973is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1974things that can appear there.
1975
1976Arguments:
1977 name point this at the name
1978 value point this at the data string
1979
1980Returns: TRUE if found an option
1981*/
1982
1983static BOOL
1984extract_option(uschar **name, uschar **value)
1985{
1986uschar *n;
ca86f471 1987uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1;
059ec3d9
PH
1988while (isspace(*v)) v--;
1989v[1] = 0;
d7a2c833
JH
1990while (v > smtp_cmd_data && *v != '=' && !isspace(*v))
1991 {
1992 /* Take care to not stop at a space embedded in a quoted local-part */
1993
1994 if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1);
1995 v--;
1996 }
059ec3d9
PH
1997
1998n = v;
fd98a5c6 1999if (*v == '=')
a2673768 2000 {
fd98a5c6
JH
2001 while(isalpha(n[-1])) n--;
2002 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
2003 if (!isspace(n[-1])) return FALSE;
2004 n[-1] = 0;
a2673768 2005 }
fd98a5c6 2006else
a2673768 2007 {
fd98a5c6
JH
2008 n++;
2009 if (v == smtp_cmd_data) return FALSE;
a2673768 2010 }
059ec3d9 2011*v++ = 0;
fd98a5c6 2012*name = n;
059ec3d9
PH
2013*value = v;
2014return TRUE;
2015}
2016
2017
2018
2019
2020
059ec3d9
PH
2021/*************************************************
2022* Reset for new message *
2023*************************************************/
2024
2025/* This function is called whenever the SMTP session is reset from
e04bfa34 2026within either of the setup functions; also from the daemon loop.
059ec3d9
PH
2027
2028Argument: the stacking pool storage reset point
2029Returns: nothing
2030*/
2031
e04bfa34 2032void
059ec3d9
PH
2033smtp_reset(void *reset_point)
2034{
059ec3d9
PH
2035recipients_list = NULL;
2036rcpt_count = rcpt_defer_count = rcpt_fail_count =
2037 raw_recipients_count = recipients_count = recipients_list_max = 0;
2e0c1448 2038message_linecount = 0;
059ec3d9 2039message_size = -1;
71fafd95 2040acl_added_headers = NULL;
e7568d51 2041acl_removed_headers = NULL;
8768d548 2042f.queue_only_policy = FALSE;
2679d413 2043rcpt_smtp_response = NULL;
88752192
JH
2044fl.rcpt_smtp_response_same = TRUE;
2045fl.rcpt_in_progress = FALSE;
8768d548 2046f.deliver_freeze = FALSE; /* Can be set by ACL */
6a3f1455 2047freeze_tell = freeze_tell_config; /* Can be set by ACL */
29aba418 2048fake_response = OK; /* Can be set by ACL */
6951ac6c 2049#ifdef WITH_CONTENT_SCAN
8768d548 2050f.no_mbox_unspool = FALSE; /* Can be set by ACL */
8523533c 2051#endif
8768d548
JH
2052f.submission_mode = FALSE; /* Can be set by ACL */
2053f.suppress_local_fixups = f.suppress_local_fixups_default; /* Can be set by ACL */
2054f.active_local_from_check = local_from_check; /* Can be set by ACL */
2055f.active_local_sender_retain = local_sender_retain; /* Can be set by ACL */
90341c71
JH
2056sending_ip_address = NULL;
2057return_path = sender_address = NULL;
2058sender_data = NULL; /* Can be set by ACL */
c679ee08
JH
2059deliver_localpart_parent = deliver_localpart_orig = NULL;
2060deliver_domain_parent = deliver_domain_orig = NULL;
90341c71 2061callout_address = NULL;
2fe1a124 2062submission_name = NULL; /* Can be set by ACL */
059ec3d9
PH
2063raw_sender = NULL; /* After SMTP rewrite, before qualifying */
2064sender_address_unrewritten = NULL; /* Set only after verify rewrite */
2065sender_verified_list = NULL; /* No senders verified */
2066memset(sender_address_cache, 0, sizeof(sender_address_cache));
2067memset(sender_domain_cache, 0, sizeof(sender_domain_cache));
6c1c3d1d 2068
059ec3d9 2069authenticated_sender = NULL;
8523533c
TK
2070#ifdef EXPERIMENTAL_BRIGHTMAIL
2071bmi_run = 0;
2072bmi_verdicts = NULL;
2073#endif
90341c71 2074dnslist_domain = dnslist_matched = NULL;
01067968
JH
2075#ifdef SUPPORT_SPF
2076spf_header_comment = spf_received = spf_result = spf_smtp_comment = NULL;
2077spf_result_guessed = FALSE;
2078#endif
80a47a2c 2079#ifndef DISABLE_DKIM
d342446f 2080dkim_cur_signer = dkim_signers =
b4757e36 2081dkim_signing_domain = dkim_signing_selector = dkim_signatures = NULL;
d342446f 2082dkim_cur_signer = dkim_signers = dkim_signing_domain = dkim_signing_selector = NULL;
8768d548 2083f.dkim_disable_verify = FALSE;
64b67b65 2084dkim_collect_input = 0;
d342446f
JH
2085dkim_verify_overall = dkim_verify_status = dkim_verify_reason = NULL;
2086dkim_key_length = 0;
2087dkim_verify_signers = US"$dkim_signers";
f7572e5a 2088#endif
b4757e36 2089#ifdef EXPERIMENTAL_DMARC
8768d548 2090f.dmarc_has_been_checked = f.dmarc_disable_verify = f.dmarc_enable_forensic = FALSE;
8aeef98a 2091dmarc_domain_policy = dmarc_status = dmarc_status_text =
6372d4c9 2092dmarc_used_domain = NULL;
f7572e5a 2093#endif
01067968
JH
2094#ifdef EXPERIMENTAL_ARC
2095arc_state = arc_state_reason = NULL;
b4757e36 2096#endif
aa368db3
JH
2097dsn_ret = 0;
2098dsn_envid = NULL;
90341c71 2099deliver_host = deliver_host_address = NULL; /* Can be set by ACL */
aa368db3
JH
2100#ifndef DISABLE_PRDR
2101prdr_requested = FALSE;
2102#endif
8c5d388a 2103#ifdef SUPPORT_I18N
d1a13eea
JH
2104message_smtputf8 = FALSE;
2105#endif
059ec3d9
PH
2106body_linecount = body_zerocount = 0;
2107
870f6ba8
TF
2108sender_rate = sender_rate_limit = sender_rate_period = NULL;
2109ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */
2110 /* Note that ratelimiters_conn persists across resets. */
2111
38a0a95f 2112/* Reset message ACL variables */
47ca6d6c 2113
38a0a95f 2114acl_var_m = NULL;
059ec3d9
PH
2115
2116/* The message body variables use malloc store. They may be set if this is
2117not the first message in an SMTP session and the previous message caused them
2118to be referenced in an ACL. */
2119
90341c71 2120if (message_body)
059ec3d9
PH
2121 {
2122 store_free(message_body);
2123 message_body = NULL;
2124 }
2125
90341c71 2126if (message_body_end)
059ec3d9
PH
2127 {
2128 store_free(message_body_end);
2129 message_body_end = NULL;
2130 }
2131
2132/* Warning log messages are also saved in malloc store. They are saved to avoid
2133repetition in the same message, but it seems right to repeat them for different
4e88a19f 2134messages. */
059ec3d9 2135
90341c71 2136while (acl_warn_logged)
059ec3d9
PH
2137 {
2138 string_item *this = acl_warn_logged;
2139 acl_warn_logged = acl_warn_logged->next;
2140 store_free(this);
2141 }
90341c71 2142store_reset(reset_point);
059ec3d9
PH
2143}
2144
2145
2146
2147
2148
2149/*************************************************
2150* Initialize for incoming batched SMTP message *
2151*************************************************/
2152
2153/* This function is called from smtp_setup_msg() in the case when
2154smtp_batched_input is true. This happens when -bS is used to pass a whole batch
2155of messages in one file with SMTP commands between them. All errors must be
2156reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
2157relevant. After an error on a sender, or an invalid recipient, the remainder
2158of the message is skipped. The value of received_protocol is already set.
2159
2160Argument: none
2161Returns: > 0 message successfully started (reached DATA)
2162 = 0 QUIT read or end of file reached
2163 < 0 should not occur
2164*/
2165
2166static int
2167smtp_setup_batch_msg(void)
2168{
2169int done = 0;
2170void *reset_point = store_get(0);
2171
2172/* Save the line count at the start of each transaction - single commands
2173like HELO and RSET count as whole transactions. */
2174
2175bsmtp_transaction_linecount = receive_linecount;
2176
2177if ((receive_feof)()) return 0; /* Treat EOF as QUIT */
2178
57cc2785 2179cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg");
059ec3d9
PH
2180smtp_reset(reset_point); /* Reset for start of message */
2181
2182/* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
2183value. The values are 2 larger than the required yield of the function. */
2184
2185while (done <= 0)
2186 {
2187 uschar *errmess;
2188 uschar *recipient = NULL;
2189 int start, end, sender_domain, recipient_domain;
2190
bd8fbe36 2191 switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED))
059ec3d9
PH
2192 {
2193 /* The HELO/EHLO commands set sender_address_helo if they have
2194 valid data; otherwise they are ignored, except that they do
2195 a reset of the state. */
2196
2197 case HELO_CMD:
2198 case EHLO_CMD:
2199
db57e575
JH
2200 check_helo(smtp_cmd_data);
2201 /* Fall through */
059ec3d9
PH
2202
2203 case RSET_CMD:
db57e575
JH
2204 cancel_cutthrough_connection(TRUE, US"RSET received");
2205 smtp_reset(reset_point);
2206 bsmtp_transaction_linecount = receive_linecount;
2207 break;
059ec3d9
PH
2208
2209
2210 /* The MAIL FROM command requires an address as an operand. All we
2211 do here is to parse it for syntactic correctness. The form "<>" is
2212 a special case which converts into an empty string. The start/end
2213 pointers in the original are not used further for this address, as
2214 it is the canonical extracted address which is all that is kept. */
2215
2216 case MAIL_CMD:
db57e575
JH
2217 smtp_mailcmd_count++; /* Count for no-mail log */
2218 if (sender_address != NULL)
2219 /* The function moan_smtp_batch() does not return. */
2220 moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given");
059ec3d9 2221
db57e575
JH
2222 if (smtp_cmd_data[0] == 0)
2223 /* The function moan_smtp_batch() does not return. */
2224 moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand");
059ec3d9 2225
db57e575 2226 /* Reset to start of message */
059ec3d9 2227
db57e575
JH
2228 cancel_cutthrough_connection(TRUE, US"MAIL received");
2229 smtp_reset(reset_point);
059ec3d9 2230
db57e575 2231 /* Apply SMTP rewrite */
059ec3d9 2232
db57e575
JH
2233 raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)?
2234 rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE,
2235 US"", global_rewrite_rules) : smtp_cmd_data;
059ec3d9 2236
db57e575 2237 /* Extract the address; the TRUE flag allows <> as valid */
059ec3d9 2238
db57e575
JH
2239 raw_sender =
2240 parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain,
2241 TRUE);
059ec3d9 2242
db57e575
JH
2243 if (!raw_sender)
2244 /* The function moan_smtp_batch() does not return. */
2245 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9 2246
db57e575 2247 sender_address = string_copy(raw_sender);
059ec3d9 2248
db57e575 2249 /* Qualify unqualified sender addresses if permitted to do so. */
059ec3d9 2250
db57e575
JH
2251 if ( !sender_domain
2252 && sender_address[0] != 0 && sender_address[0] != '@')
8768d548 2253 if (f.allow_unqualified_sender)
db57e575
JH
2254 {
2255 sender_address = rewrite_address_qualify(sender_address, FALSE);
2256 DEBUG(D_receive) debug_printf("unqualified address %s accepted "
2257 "and rewritten\n", raw_sender);
2258 }
2259 /* The function moan_smtp_batch() does not return. */
2260 else
2261 moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain "
2262 "a domain");
2263 break;
059ec3d9
PH
2264
2265
2266 /* The RCPT TO command requires an address as an operand. All we do
2267 here is to parse it for syntactic correctness. There may be any number
2268 of RCPT TO commands, specifying multiple senders. We build them all into
2269 a data structure that is in argc/argv format. The start/end values
2270 given by parse_extract_address are not used, as we keep only the
2271 extracted address. */
2272
2273 case RCPT_CMD:
db57e575
JH
2274 if (!sender_address)
2275 /* The function moan_smtp_batch() does not return. */
2276 moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given");
059ec3d9 2277
db57e575
JH
2278 if (smtp_cmd_data[0] == 0)
2279 /* The function moan_smtp_batch() does not return. */
2280 moan_smtp_batch(smtp_cmd_buffer,
2281 "501 RCPT TO must have an address operand");
059ec3d9 2282
db57e575 2283 /* Check maximum number allowed */
059ec3d9 2284
db57e575
JH
2285 if (recipients_max > 0 && recipients_count + 1 > recipients_max)
2286 /* The function moan_smtp_batch() does not return. */
2287 moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients",
2288 recipients_max_reject? "552": "452");
059ec3d9 2289
db57e575
JH
2290 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
2291 recipient address */
059ec3d9 2292
db57e575
JH
2293 recipient = rewrite_existflags & rewrite_smtp
2294 ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"",
2295 global_rewrite_rules)
2296 : smtp_cmd_data;
059ec3d9 2297
db57e575
JH
2298 recipient = parse_extract_address(recipient, &errmess, &start, &end,
2299 &recipient_domain, FALSE);
059ec3d9 2300
db57e575
JH
2301 if (!recipient)
2302 /* The function moan_smtp_batch() does not return. */
2303 moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess);
059ec3d9 2304
db57e575
JH
2305 /* If the recipient address is unqualified, qualify it if permitted. Then
2306 add it to the list of recipients. */
059ec3d9 2307
db57e575 2308 if (!recipient_domain)
8768d548 2309 if (f.allow_unqualified_recipient)
db57e575
JH
2310 {
2311 DEBUG(D_receive) debug_printf("unqualified address %s accepted\n",
2312 recipient);
2313 recipient = rewrite_address_qualify(recipient, TRUE);
2314 }
2315 /* The function moan_smtp_batch() does not return. */
2316 else
2317 moan_smtp_batch(smtp_cmd_buffer,
2318 "501 recipient address must contain a domain");
2319
2320 receive_add_recipient(recipient, -1);
2321 break;
059ec3d9
PH
2322
2323
2324 /* The DATA command is legal only if it follows successful MAIL FROM
2325 and RCPT TO commands. This function is complete when a valid DATA
2326 command is encountered. */
2327
2328 case DATA_CMD:
db57e575
JH
2329 if (!sender_address || recipients_count <= 0)
2330 /* The function moan_smtp_batch() does not return. */
2331 if (!sender_address)
2332 moan_smtp_batch(smtp_cmd_buffer,
2333 "503 MAIL FROM:<sender> command must precede DATA");
2334 else
2335 moan_smtp_batch(smtp_cmd_buffer,
2336 "503 RCPT TO:<recipient> must precede DATA");
059ec3d9 2337 else
db57e575
JH
2338 {
2339 done = 3; /* DATA successfully achieved */
2340 message_ended = END_NOTENDED; /* Indicate in middle of message */
2341 }
2342 break;
059ec3d9
PH
2343
2344
2345 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
2346
2347 case VRFY_CMD:
2348 case EXPN_CMD:
2349 case HELP_CMD:
2350 case NOOP_CMD:
2351 case ETRN_CMD:
db57e575
JH
2352 bsmtp_transaction_linecount = receive_linecount;
2353 break;
059ec3d9
PH
2354
2355
2356 case EOF_CMD:
2357 case QUIT_CMD:
db57e575
JH
2358 done = 2;
2359 break;
059ec3d9
PH
2360
2361
2362 case BADARG_CMD:
db57e575
JH
2363 /* The function moan_smtp_batch() does not return. */
2364 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data");
2365 break;
059ec3d9
PH
2366
2367
2368 case BADCHAR_CMD:
db57e575
JH
2369 /* The function moan_smtp_batch() does not return. */
2370 moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command");
2371 break;
059ec3d9
PH
2372
2373
2374 default:
db57e575
JH
2375 /* The function moan_smtp_batch() does not return. */
2376 moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized");
2377 break;
059ec3d9
PH
2378 }
2379 }
2380
2381return done - 2; /* Convert yield values */
2382}
2383
2384
2385
2386
13c7874e 2387#ifdef SUPPORT_TLS
cf0c6164
JH
2388static BOOL
2389smtp_log_tls_fail(uschar * errstr)
2390{
2391uschar * conn_info = smtp_get_connection_info();
2392
2393if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
2394/* I'd like to get separated H= here, but too hard for now */
2395
2396log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
2397return FALSE;
2398}
13c7874e 2399#endif
cf0c6164
JH
2400
2401
a2673768
JH
2402
2403
2404#ifdef TCP_FASTOPEN
2405static void
2406tfo_in_check(void)
2407{
2408# ifdef TCP_INFO
2409struct tcp_info tinfo;
2410socklen_t len = sizeof(tinfo);
2411
ee8b8090 2412if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
dbcb6d0a 2413#ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11 does not seem to have this yet */
ee8b8090
JH
2414 if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA)
2415 {
2416 DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
2417 f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE;
2418 }
dbcb6d0a
JH
2419 else
2420#endif
2421 if (tinfo.tcpi_state == TCP_SYN_RECV)
ee8b8090
JH
2422 {
2423 DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
2424 f.tcp_in_fastopen = TRUE;
2425 }
a2673768
JH
2426# endif
2427}
2428#endif
2429
2430
059ec3d9
PH
2431/*************************************************
2432* Start an SMTP session *
2433*************************************************/
2434
2435/* This function is called at the start of an SMTP session. Thereafter,
2436smtp_setup_msg() is called to initiate each separate message. This
2437function does host-specific testing, and outputs the banner line.
2438
2439Arguments: none
2440Returns: FALSE if the session can not continue; something has
2441 gone wrong, or the connection to the host is blocked
2442*/
2443
2444BOOL
2445smtp_start_session(void)
2446{
acec9514 2447int esclen;
4e88a19f
PH
2448uschar *user_msg, *log_msg;
2449uschar *code, *esc;
acec9514
JH
2450uschar *p, *s;
2451gstring * ss;
059ec3d9 2452
0f1a8658 2453gettimeofday(&smtp_connection_start, NULL);
b4ed4da0
PH
2454for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++)
2455 smtp_connection_had[smtp_ch_index] = SCH_NONE;
2456smtp_ch_index = 0;
2457
00f00ca5
PH
2458/* Default values for certain variables */
2459
88752192 2460fl.helo_seen = fl.esmtp = fl.helo_accept_junk = FALSE;
b4ed4da0 2461smtp_mailcmd_count = 0;
059ec3d9
PH
2462count_nonmail = TRUE_UNSET;
2463synprot_error_count = unknown_command_count = nonmail_command_count = 0;
2464smtp_delay_mail = smtp_rlm_base;
88752192 2465fl.auth_advertised = FALSE;
8768d548
JH
2466f.smtp_in_pipelining_advertised = f.smtp_in_pipelining_used = FALSE;
2467f.pipelining_enable = TRUE;
059ec3d9 2468sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING;
88752192 2469fl.smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */
059ec3d9 2470
33d73e3b
PH
2471/* If receiving by -bs from a trusted user, or testing with -bh, we allow
2472authentication settings from -oMaa to remain in force. */
2473
8768d548 2474if (!host_checking && !f.sender_host_notsocket)
c44ff8be 2475 sender_host_auth_pubname = sender_host_authenticated = NULL;
059ec3d9
PH
2476authenticated_by = NULL;
2477
2478#ifdef SUPPORT_TLS
817d9f57 2479tls_in.cipher = tls_in.peerdn = NULL;
9d1c15ef
JH
2480tls_in.ourcert = tls_in.peercert = NULL;
2481tls_in.sni = NULL;
44662487 2482tls_in.ocsp = OCSP_NOT_REQ;
88752192 2483fl.tls_advertised = FALSE;
8ac90765 2484# ifdef EXPERIMENTAL_REQUIRETLS
88752192 2485fl.requiretls_advertised = FALSE;
8ac90765 2486# endif
059ec3d9 2487#endif
88752192 2488fl.dsn_advertised = FALSE;
8c5d388a 2489#ifdef SUPPORT_I18N
88752192 2490fl.smtputf8_advertised = FALSE;
d1a13eea 2491#endif
059ec3d9
PH
2492
2493/* Reset ACL connection variables */
2494
38a0a95f 2495acl_var_c = NULL;
059ec3d9 2496
ca86f471 2497/* Allow for trailing 0 in the command and data buffers. */
3ee512ff 2498
bd8fbe36 2499if (!(smtp_cmd_buffer = US malloc(2*SMTP_CMD_BUFFER_SIZE + 2)))
059ec3d9
PH
2500 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2501 "malloc() failed for SMTP command buffer");
40c90bca 2502
2416c261 2503smtp_cmd_buffer[0] = 0;
bd8fbe36 2504smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1;
059ec3d9
PH
2505
2506/* For batched input, the protocol setting can be overridden from the
2507command line by a trusted caller. */
2508
2509if (smtp_batched_input)
2510 {
40c90bca 2511 if (!received_protocol) received_protocol = US"local-bsmtp";
059ec3d9
PH
2512 }
2513
2514/* For non-batched SMTP input, the protocol setting is forced here. It will be
2515reset later if any of EHLO/AUTH/STARTTLS are received. */
2516
2517else
2518 received_protocol =
e524074d 2519 (sender_host_address ? protocols : protocols_local) [pnormal];
059ec3d9
PH
2520
2521/* Set up the buffer for inputting using direct read() calls, and arrange to
ecce6d9a
JH
2522call the local functions instead of the standard C ones. Place a NUL at the
2523end of the buffer to safety-stop C-string reads from it. */
059ec3d9 2524
5903c6ff 2525if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE)))
059ec3d9 2526 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer");
ecce6d9a 2527smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0';
40c90bca 2528
059ec3d9 2529receive_getc = smtp_getc;
0d81dabc 2530receive_getbuf = smtp_getbuf;
584e96c6 2531receive_get_cache = smtp_get_cache;
059ec3d9
PH
2532receive_ungetc = smtp_ungetc;
2533receive_feof = smtp_feof;
2534receive_ferror = smtp_ferror;
58eb016e 2535receive_smtp_buffered = smtp_buffered;
059ec3d9
PH
2536smtp_inptr = smtp_inend = smtp_inbuffer;
2537smtp_had_eof = smtp_had_error = 0;
2538
2539/* Set up the message size limit; this may be host-specific */
2540
d45b1de8 2541thismessage_size_limit = expand_string_integer(message_size_limit, TRUE);
db57e575 2542if (expand_string_message)
059ec3d9
PH
2543 {
2544 if (thismessage_size_limit == -1)
2545 log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: "
2546 "%s", expand_string_message);
2547 else
2548 log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: "
2549 "%s", expand_string_message);
2550 smtp_closedown(US"Temporary local problem - please try later");
2551 return FALSE;
2552 }
2553
2554/* When a message is input locally via the -bs or -bS options, sender_host_
2555unknown is set unless -oMa was used to force an IP address, in which case it
2556is checked like a real remote connection. When -bs is used from inetd, this
2557flag is not set, causing the sending host to be checked. The code that deals
2558with IP source routing (if configured) is never required for -bs or -bS and
2559the flag sender_host_notsocket is used to suppress it.
2560
2561If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
2562reserve for certain hosts and/or networks. */
2563
8768d548 2564if (!f.sender_host_unknown)
059ec3d9
PH
2565 {
2566 int rc;
2567 BOOL reserved_host = FALSE;
2568
2569 /* Look up IP options (source routing info) on the socket if this is not an
2570 -oMa "host", and if any are found, log them and drop the connection.
2571
2572 Linux (and others now, see below) is different to everyone else, so there
2573 has to be some conditional compilation here. Versions of Linux before 2.1.15
2574 used a structure whose name was "options". Somebody finally realized that
2575 this name was silly, and it got changed to "ip_options". I use the
2576 newer name here, but there is a fudge in the script that sets up os.h
2577 to define a macro in older Linux systems.
2578
2579 Sigh. Linux is a fast-moving target. Another generation of Linux uses
2580 glibc 2, which has chosen ip_opts for the structure name. This is now
2581 really a glibc thing rather than a Linux thing, so the condition name
2582 has been changed to reflect this. It is relevant also to GNU/Hurd.
2583
2584 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
2585 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
2586 a special macro defined in the os.h file.
2587
2588 Some DGUX versions on older hardware appear not to support IP options at
2589 all, so there is now a general macro which can be set to cut out this
2590 support altogether.
2591
2592 How to do this properly in IPv6 is not yet known. */
2593
e0574cb5 2594#if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
059ec3d9
PH
2595
2596 #ifdef GLIBC_IP_OPTIONS
2597 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
2598 #define OPTSTYLE 1
2599 #else
2600 #define OPTSTYLE 2
2601 #endif
2602 #elif defined DARWIN_IP_OPTIONS
2603 #define OPTSTYLE 2
2604 #else
2605 #define OPTSTYLE 3
2606 #endif
2607
8768d548 2608 if (!host_checking && !f.sender_host_notsocket)
059ec3d9
PH
2609 {
2610 #if OPTSTYLE == 1
36a3b041 2611 EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN;
059ec3d9
PH
2612 struct ip_options *ipopt = store_get(optlen);
2613 #elif OPTSTYLE == 2
2614 struct ip_opts ipoptblock;
2615 struct ip_opts *ipopt = &ipoptblock;
36a3b041 2616 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2617 #else
2618 struct ipoption ipoptblock;
2619 struct ipoption *ipopt = &ipoptblock;
36a3b041 2620 EXIM_SOCKLEN_T optlen = sizeof(ipoptblock);
059ec3d9
PH
2621 #endif
2622
2623 /* Occasional genuine failures of getsockopt() have been seen - for
2624 example, "reset by peer". Therefore, just log and give up on this
2625 call, unless the error is ENOPROTOOPT. This error is given by systems
2626 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
2627 of writing. So for that error, carry on - we just can't do an IP options
2628 check. */
2629
2630 DEBUG(D_receive) debug_printf("checking for IP options\n");
2631
5903c6ff 2632 if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, US (ipopt),
059ec3d9
PH
2633 &optlen) < 0)
2634 {
2635 if (errno != ENOPROTOOPT)
2636 {
2637 log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s",
2638 host_and_ident(FALSE), strerror(errno));
925ac8e4 2639 smtp_printf("451 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2640 return FALSE;
2641 }
2642 }
2643
2644 /* Deal with any IP options that are set. On the systems I have looked at,
2645 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
2646 more logging data than will fit in big_buffer. Nevertheless, after somebody
2647 questioned this code, I've added in some paranoid checking. */
2648
2649 else if (optlen > 0)
2650 {
2651 uschar *p = big_buffer;
2652 uschar *pend = big_buffer + big_buffer_size;
2653 uschar *opt, *adptr;
2654 int optcount;
2655 struct in_addr addr;
2656
2657 #if OPTSTYLE == 1
5903c6ff 2658 uschar *optstart = US (ipopt->__data);
059ec3d9 2659 #elif OPTSTYLE == 2
5903c6ff 2660 uschar *optstart = US (ipopt->ip_opts);
059ec3d9 2661 #else
5903c6ff 2662 uschar *optstart = US (ipopt->ipopt_list);
059ec3d9
PH
2663 #endif
2664
2665 DEBUG(D_receive) debug_printf("IP options exist\n");
2666
2667 Ustrcpy(p, "IP options on incoming call:");
2668 p += Ustrlen(p);
2669
2670 for (opt = optstart; opt != NULL &&
5903c6ff 2671 opt < US (ipopt) + optlen;)
059ec3d9
PH
2672 {
2673 switch (*opt)
2674 {
2675 case IPOPT_EOL:
2676 opt = NULL;
2677 break;
2678
2679 case IPOPT_NOP:
2680 opt++;
2681 break;
2682
2683 case IPOPT_SSRR:
2684 case IPOPT_LSRR:
2685 if (!string_format(p, pend-p, " %s [@%s",
2686 (*opt == IPOPT_SSRR)? "SSRR" : "LSRR",
2687 #if OPTSTYLE == 1
2688 inet_ntoa(*((struct in_addr *)(&(ipopt->faddr))))))
2689 #elif OPTSTYLE == 2
2690 inet_ntoa(ipopt->ip_dst)))
2691 #else
2692 inet_ntoa(ipopt->ipopt_dst)))
2693 #endif
2694 {
2695 opt = NULL;
2696 break;
2697 }
2698
2699 p += Ustrlen(p);
2700 optcount = (opt[1] - 3) / sizeof(struct in_addr);
2701 adptr = opt + 3;
2702 while (optcount-- > 0)
2703 {
2704 memcpy(&addr, adptr, sizeof(addr));
2705 if (!string_format(p, pend - p - 1, "%s%s",
2706 (optcount == 0)? ":" : "@", inet_ntoa(addr)))
2707 {
2708 opt = NULL;
2709 break;
2710 }
2711 p += Ustrlen(p);
2712 adptr += sizeof(struct in_addr);
2713 }
2714 *p++ = ']';
2715 opt += opt[1];
2716 break;
2717
2718 default:
2719 {
2720 int i;
2721 if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; }
2722 Ustrcat(p, "[ ");
2723 p += 2;
2724 for (i = 0; i < opt[1]; i++)
5976eb99 2725 p += sprintf(CS p, "%2.2x ", opt[i]);
059ec3d9
PH
2726 *p++ = ']';
2727 }
2728 opt += opt[1];
2729 break;
2730 }
2731 }
2732
2733 *p = 0;
2734 log_write(0, LOG_MAIN, "%s", big_buffer);
2735
2736 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2737
2738 log_write(0, LOG_MAIN|LOG_REJECT,
2739 "connection from %s refused (IP options)", host_and_ident(FALSE));
2740
925ac8e4 2741 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2742 return FALSE;
2743 }
2744
2745 /* Length of options = 0 => there are no options */
2746
2747 else DEBUG(D_receive) debug_printf("no IP options found\n");
2748 }
e0574cb5 2749#endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
059ec3d9
PH
2750
2751 /* Set keep-alive in socket options. The option is on by default. This
2752 setting is an attempt to get rid of some hanging connections that stick in
2753 read() when the remote end (usually a dialup) goes away. */
2754
8768d548 2755 if (smtp_accept_keepalive && !f.sender_host_notsocket)
059ec3d9
PH
2756 ip_keepalive(fileno(smtp_out), sender_host_address, FALSE);
2757
2758 /* If the current host matches host_lookup, set the name by doing a
2759 reverse lookup. On failure, sender_host_name will be NULL and
2760 host_lookup_failed will be TRUE. This may or may not be serious - optional
2761 checks later. */
2762
2763 if (verify_check_host(&host_lookup) == OK)
2764 {
2765 (void)host_name_lookup();
2766 host_build_sender_fullhost();
2767 }
2768
2769 /* Delay this until we have the full name, if it is looked up. */
2770
2771 set_process_info("handling incoming connection from %s",
2772 host_and_ident(FALSE));
2773
1ad6489e
JH
2774 /* Expand smtp_receive_timeout, if needed */
2775
2776 if (smtp_receive_timeout_s)
2777 {
2778 uschar * exp;
2779 if ( !(exp = expand_string(smtp_receive_timeout_s))
2780 || !(*exp)
2781 || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0
2782 )
2783 log_write(0, LOG_MAIN|LOG_PANIC,
2784 "bad value for smtp_receive_timeout: '%s'", exp ? exp : US"");
2785 }
2786
059ec3d9
PH
2787 /* Test for explicit connection rejection */
2788
2789 if (verify_check_host(&host_reject_connection) == OK)
2790 {
2791 log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection "
2792 "from %s (host_reject_connection)", host_and_ident(FALSE));
925ac8e4 2793 smtp_printf("554 SMTP service not available\r\n", FALSE);
059ec3d9
PH
2794 return FALSE;
2795 }
2796
afb3eaaf
PH
2797 /* Test with TCP Wrappers if so configured. There is a problem in that
2798 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2799 such as disks dying. In these cases, it is desirable to reject with a 4xx
2800 error instead of a 5xx error. There isn't a "right" way to detect such
2801 problems. The following kludge is used: errno is zeroed before calling
2802 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2803 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2804 not exist). */
059ec3d9 2805
1811cb4c 2806#ifdef USE_TCP_WRAPPERS
afb3eaaf 2807 errno = 0;
1811cb4c 2808 if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name)))
5dc43717
JJ
2809 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
2810 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name),
2811 expand_string_message);
1811cb4c 2812
5dc43717 2813 if (!hosts_ctl(tcp_wrappers_name,
1811cb4c
JH
2814 sender_host_name ? CS sender_host_name : STRING_UNKNOWN,
2815 sender_host_address ? CS sender_host_address : STRING_UNKNOWN,
2816 sender_ident ? CS sender_ident : STRING_UNKNOWN))
059ec3d9 2817 {
afb3eaaf
PH
2818 if (errno == 0 || errno == ENOENT)
2819 {
2820 HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n");
2821 log_write(L_connection_reject,
2822 LOG_MAIN|LOG_REJECT, "refused connection from %s "
2823 "(tcp wrappers)", host_and_ident(FALSE));
925ac8e4 2824 smtp_printf("554 SMTP service not available\r\n", FALSE);
afb3eaaf
PH
2825 }
2826 else
2827 {
2828 int save_errno = errno;
2829 HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected "
2830 "errno value %d\n", save_errno);
2831 log_write(L_connection_reject,
2832 LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s "
2833 "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno);
925ac8e4 2834 smtp_printf("451 Temporary local problem - please try later\r\n", FALSE);
afb3eaaf 2835 }
059ec3d9
PH
2836 return FALSE;
2837 }
1811cb4c 2838#endif
059ec3d9 2839
b01dd148
PH
2840 /* Check for reserved slots. The value of smtp_accept_count has already been
2841 incremented to include this process. */
059ec3d9
PH
2842
2843 if (smtp_accept_max > 0 &&
b01dd148 2844 smtp_accept_count > smtp_accept_max - smtp_accept_reserve)
059ec3d9
PH
2845 {
2846 if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK)
2847 {
2848 log_write(L_connection_reject,
2849 LOG_MAIN, "temporarily refused connection from %s: not in "
2850 "reserve list: connected=%d max=%d reserve=%d%s",
b01dd148 2851 host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max,
059ec3d9
PH
2852 smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : "");
2853 smtp_printf("421 %s: Too many concurrent SMTP connections; "
925ac8e4 2854 "please try again later\r\n", FALSE, smtp_active_hostname);
059ec3d9
PH
2855 return FALSE;
2856 }
2857 reserved_host = TRUE;
2858 }
2859
2860 /* If a load level above which only messages from reserved hosts are
2861 accepted is set, check the load. For incoming calls via the daemon, the
2862 check is done in the superior process if there are no reserved hosts, to
2863 save a fork. In all cases, the load average will already be available
2864 in a global variable at this point. */
2865
2866 if (smtp_load_reserve >= 0 &&
2867 load_average > smtp_load_reserve &&
2868 !reserved_host &&
2869 verify_check_host(&smtp_reserve_hosts) != OK)
2870 {
2871 log_write(L_connection_reject,
2872 LOG_MAIN, "temporarily refused connection from %s: not in "
2873 "reserve list and load average = %.2f", host_and_ident(FALSE),
2874 (double)load_average/1000.0);
925ac8e4 2875 smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE,
059ec3d9
PH
2876 smtp_active_hostname);
2877 return FALSE;
2878 }
2879
2880 /* Determine whether unqualified senders or recipients are permitted
2881 for this host. Unfortunately, we have to do this every time, in order to
2882 set the flags so that they can be inspected when considering qualifying
2883 addresses in the headers. For a site that permits no qualification, this
2884 won't take long, however. */
2885
8768d548 2886 f.allow_unqualified_sender =
059ec3d9
PH
2887 verify_check_host(&sender_unqualified_hosts) == OK;
2888
8768d548 2889 f.allow_unqualified_recipient =
059ec3d9
PH
2890 verify_check_host(&recipient_unqualified_hosts) == OK;
2891
2892 /* Determine whether HELO/EHLO is required for this host. The requirement
2893 can be hard or soft. */
2894
88752192
JH
2895 fl.helo_required = verify_check_host(&helo_verify_hosts) == OK;
2896 if (!fl.helo_required)
2897 fl.helo_verify = verify_check_host(&helo_try_verify_hosts) == OK;
059ec3d9
PH
2898
2899 /* Determine whether this hosts is permitted to send syntactic junk
2900 after a HELO or EHLO command. */
2901
88752192 2902 fl.helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK;
059ec3d9
PH
2903 }
2904
2905/* For batch SMTP input we are now done. */
2906
2907if (smtp_batched_input) return TRUE;
2908
a3c86431
TL
2909/* If valid Proxy Protocol source is connecting, set up session.
2910 * Failure will not allow any SMTP function other than QUIT. */
1811cb4c
JH
2911
2912#ifdef SUPPORT_PROXY
a3c86431 2913proxy_session = FALSE;
8768d548 2914f.proxy_session_failed = FALSE;
a3c86431 2915if (check_proxy_protocol_host())
1811cb4c
JH
2916 setup_proxy_protocol_host();
2917#endif
2918
2919 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2920 smtps port for use with older style SSL MTAs. */
2921
2922#ifdef SUPPORT_TLS
69d8eed7
JH
2923 if (tls_in.on_connect)
2924 {
2925 if (tls_server_start(tls_require_ciphers, &user_msg) != OK)
2926 return smtp_log_tls_fail(user_msg);
2927 cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
2928 }
a3c86431
TL
2929#endif
2930
1811cb4c 2931/* Run the connect ACL if it exists */
059ec3d9 2932
4e88a19f 2933user_msg = NULL;
3cc3f762 2934if (acl_smtp_connect)
059ec3d9
PH
2935 {
2936 int rc;
3cc3f762
JH
2937 if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg,
2938 &log_msg)) != OK)
059ec3d9 2939 {
3cc3f762 2940 (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg);
059ec3d9
PH
2941 return FALSE;
2942 }
2943 }
2944
2945/* Output the initial message for a two-way SMTP connection. It may contain
2946newlines, which then cause a multi-line response to be given. */
2947
4e88a19f
PH
2948code = US"220"; /* Default status code */
2949esc = US""; /* Default extended status code */
2950esclen = 0; /* Length of esc */
2951
d4ff61d1 2952if (!user_msg)
4e88a19f 2953 {
d4ff61d1 2954 if (!(s = expand_string(smtp_banner)))
4e88a19f
PH
2955 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) "
2956 "failed: %s", smtp_banner, expand_string_message);
2957 }
2958else
2959 {
2960 int codelen = 3;
2961 s = user_msg;
4f6ae5c3 2962 smtp_message_code(&code, &codelen, &s, NULL, TRUE);
d6a96edc 2963 if (codelen > 4)
4e88a19f
PH
2964 {
2965 esc = code + 4;
2966 esclen = codelen - 4;
2967 }
2968 }
059ec3d9
PH
2969
2970/* Remove any terminating newlines; might as well remove trailing space too */
2971
2972p = s + Ustrlen(s);
2973while (p > s && isspace(p[-1])) p--;
2974*p = 0;
2975
2976/* It seems that CC:Mail is braindead, and assumes that the greeting message
2977is all contained in a single IP packet. The original code wrote out the
2978greeting using several calls to fprint/fputc, and on busy servers this could
2979cause it to be split over more than one packet - which caused CC:Mail to fall
2980over when it got the second part of the greeting after sending its first
2981command. Sigh. To try to avoid this, build the complete greeting message
2982first, and output it in one fell swoop. This gives a better chance of it
2983ending up as a single packet. */
2984
acec9514 2985ss = string_get(256);
059ec3d9
PH
2986
2987p = s;
2988do /* At least once, in case we have an empty string */
2989 {
2990 int len;
2991 uschar *linebreak = Ustrchr(p, '\n');
acec9514 2992 ss = string_catn(ss, code, 3);
db57e575 2993 if (!linebreak)
059ec3d9
PH
2994 {
2995 len = Ustrlen(p);
acec9514 2996 ss = string_catn(ss, US" ", 1);
059ec3d9
PH
2997 }
2998 else
2999 {
3000 len = linebreak - p;
acec9514 3001 ss = string_catn(ss, US"-", 1);
059ec3d9 3002 }
acec9514
JH
3003 ss = string_catn(ss, esc, esclen);
3004 ss = string_catn(ss, p, len);
3005 ss = string_catn(ss, US"\r\n", 2);
059ec3d9 3006 p += len;
db57e575 3007 if (linebreak) p++;
059ec3d9 3008 }
db57e575 3009while (*p);
059ec3d9 3010
059ec3d9
PH
3011/* Before we write the banner, check that there is no input pending, unless
3012this synchronisation check is disabled. */
3013
ee8b8090
JH
3014#ifdef EXPERIMENTAL_PIPE_CONNECT
3015fl.pipe_connect_acceptable =
3016 sender_host_address && verify_check_host(&pipe_connect_advertise_hosts) == OK;
3017
a14e5636 3018if (!check_sync())
ee8b8090
JH
3019 if (fl.pipe_connect_acceptable)
3020 f.smtp_in_early_pipe_used = TRUE;
3021 else
3022#else
3023if (!check_sync())
3024#endif
3025 {
3026 unsigned n = smtp_inend - smtp_inptr;
3027 if (n > 32) n = 32;
3028
3029 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol "
3030 "synchronization error (input sent without waiting for greeting): "
3031 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE),
3032 string_printing(string_copyn(smtp_inptr, n)));
3033 smtp_printf("554 SMTP synchronization error\r\n", FALSE);
3034 return FALSE;
3035 }
059ec3d9
PH
3036
3037/* Now output the banner */
ee8b8090 3038/*XXX the ehlo-resp code does its own tls/nontls bit. Maybe subroutine that? */
059ec3d9 3039
ee8b8090
JH
3040smtp_printf("%s",
3041#ifdef EXPERIMENTAL_PIPE_CONNECT
3042 fl.pipe_connect_acceptable && pipeline_connect_sends(),
3043#else
3044 FALSE,
3045#endif
3046 string_from_gstring(ss));
a2673768
JH
3047
3048/* Attempt to see if we sent the banner before the last ACK of the 3-way
3049handshake arrived. If so we must have managed a TFO. */
3050
3051#ifdef TCP_FASTOPEN
3052tfo_in_check();
3053#endif
3054
059ec3d9
PH
3055return TRUE;
3056}
3057
3058
3059
3060
3061
3062/*************************************************
3063* Handle SMTP syntax and protocol errors *
3064*************************************************/
3065
3066/* Write to the log for SMTP syntax errors in incoming commands, if configured
3067to do so. Then transmit the error response. The return value depends on the
3068number of syntax and protocol errors in this SMTP session.
3069
3070Arguments:
3071 type error type, given as a log flag bit
3072 code response code; <= 0 means don't send a response
3073 data data to reflect in the response (can be NULL)
3074 errmess the error message
3075
3076Returns: -1 limit of syntax/protocol errors NOT exceeded
3077 +1 limit of syntax/protocol errors IS exceeded
3078
3079These values fit in with the values of the "done" variable in the main
3080processing loop in smtp_setup_msg(). */
3081
3082static int
3083synprot_error(int type, int code, uschar *data, uschar *errmess)
3084{
3085int yield = -1;
3086
3087log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s",
3088 (type == L_smtp_syntax_error)? "syntax" : "protocol",
3ee512ff 3089 string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess);
059ec3d9
PH
3090
3091if (++synprot_error_count > smtp_max_synprot_errors)
3092 {
3093 yield = 1;
3094 log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many "
3095 "syntax or protocol errors (last command was \"%s\")",
0ebc4d69 3096 host_and_ident(FALSE), string_printing(smtp_cmd_buffer));
059ec3d9
PH
3097 }
3098
3099if (code > 0)
3100 {
925ac8e4
JH
3101 smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ',
3102 data ? data : US"", data ? US": " : US"", errmess);
059ec3d9 3103 if (yield == 1)
925ac8e4 3104 smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code);
059ec3d9
PH
3105 }
3106
3107return yield;
3108}
3109
3110
3111
3112
3113/*************************************************
059ec3d9
PH
3114* Send SMTP response, possibly multiline *
3115*************************************************/
3116
3117/* There are, it seems, broken clients out there that cannot handle multiline
3118responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
3119output nothing for non-final calls, and only the first line for anything else.
3120
3121Arguments:
a5bd321b 3122 code SMTP code, may involve extended status codes
d6a96edc 3123 codelen length of smtp code; if > 4 there's an ESC
059ec3d9
PH
3124 final FALSE if the last line isn't the final line
3125 msg message text, possibly containing newlines
3126
3127Returns: nothing
3128*/
3129
3130void
a5bd321b 3131smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg)
059ec3d9 3132{
a5bd321b
PH
3133int esclen = 0;
3134uschar *esc = US"";
3135
8768d548 3136if (!final && f.no_multiline_responses) return;
059ec3d9 3137
d6a96edc 3138if (codelen > 4)
a5bd321b
PH
3139 {
3140 esc = code + 4;
3141 esclen = codelen - 4;
3142 }
3143
2679d413
PH
3144/* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
3145have had the same. Note: this code is also present in smtp_printf(). It would
3146be tidier to have it only in one place, but when it was added, it was easier to
3147do it that way, so as not to have to mess with the code for the RCPT command,
3148which sometimes uses smtp_printf() and sometimes smtp_respond(). */
3149
88752192 3150if (fl.rcpt_in_progress)
2679d413
PH
3151 {
3152 if (rcpt_smtp_response == NULL)
3153 rcpt_smtp_response = string_copy(msg);
88752192 3154 else if (fl.rcpt_smtp_response_same &&
2679d413 3155 Ustrcmp(rcpt_smtp_response, msg) != 0)
88752192
JH
3156 fl.rcpt_smtp_response_same = FALSE;
3157 fl.rcpt_in_progress = FALSE;
2679d413
PH
3158 }
3159
e5de01f0 3160/* Now output the message, splitting it up into multiple lines if necessary.
925ac8e4
JH
3161We only handle pipelining these responses as far as nonfinal/final groups,
3162not the whole MAIL/RCPT/DATA response set. */
2679d413 3163
059ec3d9
PH
3164for (;;)
3165 {
3166 uschar *nl = Ustrchr(msg, '\n');
3167 if (nl == NULL)
3168 {
925ac8e4 3169 smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg);
059ec3d9
PH
3170 return;
3171 }
8768d548 3172 else if (nl[1] == 0 || f.no_multiline_responses)
059ec3d9 3173 {
925ac8e4 3174 smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc,
a5bd321b 3175 (int)(nl - msg), msg);
059ec3d9
PH
3176 return;
3177 }
3178 else
3179 {
925ac8e4 3180 smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg);
059ec3d9
PH
3181 msg = nl + 1;
3182 while (isspace(*msg)) msg++;
3183 }
3184 }
3185}
3186
3187
3188
3189
3190/*************************************************
4e88a19f
PH
3191* Parse user SMTP message *
3192*************************************************/
3193
3194/* This function allows for user messages overriding the response code details
3195by providing a suitable response code string at the start of the message
3196user_msg. Check the message for starting with a response code and optionally an
3197extended status code. If found, check that the first digit is valid, and if so,
3198change the code pointer and length to use the replacement. An invalid code
3199causes a panic log; in this case, if the log messages is the same as the user
3200message, we must also adjust the value of the log message to show the code that
3201is actually going to be used (the original one).
3202
3203This function is global because it is called from receive.c as well as within
3204this module.
3205
d6a96edc
PH
3206Note that the code length returned includes the terminating whitespace
3207character, which is always included in the regex match.
3208
4e88a19f
PH
3209Arguments:
3210 code SMTP code, may involve extended status codes
d6a96edc 3211 codelen length of smtp code; if > 4 there's an ESC
4e88a19f
PH
3212 msg message text
3213 log_msg optional log message, to be adjusted with the new SMTP code
4f6ae5c3 3214 check_valid if true, verify the response code
4e88a19f
PH
3215
3216Returns: nothing
3217*/
3218
3219void
4f6ae5c3
JH
3220smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg,
3221 BOOL check_valid)
4e88a19f
PH
3222{
3223int n;
3224int ovector[3];
3225
4f6ae5c3 3226if (!msg || !*msg) return;
4e88a19f 3227
4f6ae5c3
JH
3228if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0,
3229 PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return;
4e88a19f 3230
4f6ae5c3 3231if (check_valid && (*msg)[0] != (*code)[0])
4e88a19f
PH
3232 {
3233 log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with "
3234 "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg);
3235 if (log_msg != NULL && *log_msg == *msg)
3236 *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]);
3237 }
3238else
3239 {
3240 *code = *msg;
3241 *codelen = ovector[1]; /* Includes final space */
3242 }
3243*msg += ovector[1]; /* Chop the code off the message */
3244return;
3245}
3246
3247
3248
3249
3250/*************************************************
059ec3d9
PH
3251* Handle an ACL failure *
3252*************************************************/
3253
3254/* This function is called when acl_check() fails. As well as calls from within
3255this module, it is called from receive.c for an ACL after DATA. It sorts out
5b6f7658 3256logging the incident, and sends the error response. A message containing
059ec3d9
PH
3257newlines is turned into a multiline SMTP response, but for logging, only the
3258first line is used.
3259
a5bd321b
PH
3260There's a table of default permanent failure response codes to use in
3261globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
3262defaults disabled in Exim. However, discussion in connection with RFC 821bis
3263(aka RFC 2821) has concluded that the response should be 252 in the disabled
3264state, because there are broken clients that try VRFY before RCPT. A 5xx
3265response should be given only when the address is positively known to be
4f6ae5c3
JH
3266undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
3267no explicit code, but if there is one we let it know best.
3268Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
a5bd321b
PH
3269
3270From Exim 4.63, it is possible to override the response code details by
3271providing a suitable response code string at the start of the message provided
3272in user_msg. The code's first digit is checked for validity.
059ec3d9
PH
3273
3274Arguments:
4f6ae5c3
JH
3275 where where the ACL was called from
3276 rc the failure code
3277 user_msg a message that can be included in an SMTP response
3278 log_msg a message for logging
059ec3d9
PH
3279
3280Returns: 0 in most cases
3281 2 if the failure code was FAIL_DROP, in which case the
3282 SMTP connection should be dropped (this value fits with the
3283 "done" variable in smtp_setup_msg() below)
3284*/
3285
3286int
3287smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg)
3288{
059ec3d9 3289BOOL drop = rc == FAIL_DROP;
a5bd321b 3290int codelen = 3;
a5bd321b 3291uschar *smtp_code;
059ec3d9
PH
3292uschar *lognl;
3293uschar *sender_info = US"";
64ffc24f 3294uschar *what =
8523533c 3295#ifdef WITH_CONTENT_SCAN
3cc3f762 3296 where == ACL_WHERE_MIME ? US"during MIME ACL checks" :
8e669ac1 3297#endif
3cc3f762
JH
3298 where == ACL_WHERE_PREDATA ? US"DATA" :
3299 where == ACL_WHERE_DATA ? US"after DATA" :
8ccd00b1 3300#ifndef DISABLE_PRDR
3cc3f762 3301 where == ACL_WHERE_PRDR ? US"after DATA PRDR" :
fd98a5c6 3302#endif
3cc3f762
JH
3303 smtp_cmd_data ?
3304 string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) :
3305 string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]);
059ec3d9
PH
3306
3307if (drop) rc = FAIL;
3308
4e88a19f 3309/* Set the default SMTP code, and allow a user message to change it. */
a5bd321b 3310
4f6ae5c3
JH
3311smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451";
3312smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg,
3313 where != ACL_WHERE_VRFY);
a5bd321b 3314
059ec3d9
PH
3315/* We used to have sender_address here; however, there was a bug that was not
3316updating sender_address after a rewrite during a verify. When this bug was
3317fixed, sender_address at this point became the rewritten address. I'm not sure
3318this is what should be logged, so I've changed to logging the unrewritten
3319address to retain backward compatibility. */
3320
8523533c 3321#ifndef WITH_CONTENT_SCAN
059ec3d9 3322if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA)
8523533c
TK
3323#else
3324if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME)
3325#endif
059ec3d9 3326 {
b98bb9ac
PP
3327 sender_info = string_sprintf("F=<%s>%s%s%s%s ",
3328 sender_address_unrewritten ? sender_address_unrewritten : sender_address,
3329 sender_host_authenticated ? US" A=" : US"",
3330 sender_host_authenticated ? sender_host_authenticated : US"",
3331 sender_host_authenticated && authenticated_id ? US":" : US"",
3332 sender_host_authenticated && authenticated_id ? authenticated_id : US""
3333 );
059ec3d9
PH
3334 }
3335
3336/* If there's been a sender verification failure with a specific message, and
3337we have not sent a response about it yet, do so now, as a preliminary line for
278c6e6c
PH
3338failures, but not defers. However, always log it for defer, and log it for fail
3339unless the sender_verify_fail log selector has been turned off. */
059ec3d9 3340
02b41d71 3341if (sender_verified_failed &&
059ec3d9
PH
3342 !testflag(sender_verified_failed, af_sverify_told))
3343 {
88752192
JH
3344 BOOL save_rcpt_in_progress = fl.rcpt_in_progress;
3345 fl.rcpt_in_progress = FALSE; /* So as not to treat these as the error */
2679d413 3346
059ec3d9
PH
3347 setflag(sender_verified_failed, af_sverify_told);
3348
6c6d6e48 3349 if (rc != FAIL || LOGGING(sender_verify_fail))
278c6e6c
PH
3350 log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s",
3351 host_and_ident(TRUE),
3352 ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail",
3353 sender_verified_failed->address,
3354 (sender_verified_failed->message == NULL)? US"" :
3355 string_sprintf(": %s", sender_verified_failed->message));
059ec3d9 3356
02b41d71 3357 if (rc == FAIL && sender_verified_failed->user_message)
a5bd321b 3358 smtp_respond(smtp_code, codelen, FALSE, string_sprintf(
059ec3d9
PH
3359 testflag(sender_verified_failed, af_verify_pmfail)?
3360 "Postmaster verification failed while checking <%s>\n%s\n"
3361 "Several RFCs state that you are required to have a postmaster\n"
3362 "mailbox for each mail domain. This host does not accept mail\n"
3363 "from domains whose servers reject the postmaster address."
3364 :
3365 testflag(sender_verified_failed, af_verify_nsfail)?
3366 "Callback setup failed while verifying <%s>\n%s\n"
3367 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
3368 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
3369 "RFC requirements, and stops you from receiving standard bounce\n"
3370 "messages. This host does not accept mail from domains whose servers\n"
3371 "refuse bounces."
3372 :
3373 "Verification failed for <%s>\n%s",
3374 sender_verified_failed->address,
3375 sender_verified_failed->user_message));
2679d413 3376
88752192 3377 fl.rcpt_in_progress = save_rcpt_in_progress;
059ec3d9
PH
3378 }
3379
3380/* Sort out text for logging */
3381
3cc3f762
JH
3382log_msg = log_msg ? string_sprintf(": %s", log_msg) : US"";
3383if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0;
059ec3d9
PH
3384
3385/* Send permanent failure response to the command, but the code used isn't
3386always a 5xx one - see comments at the start of this function. If the original
3387rc was FAIL_DROP we drop the connection and yield 2. */
3388
ff5929e3
JH
3389if (rc == FAIL)
3390 smtp_respond(smtp_code, codelen, TRUE,
3391 user_msg ? user_msg : US"Administrative prohibition");
059ec3d9
PH
3392
3393/* Send temporary failure response to the command. Don't give any details,
3394unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
3395verb, and for a header verify when smtp_return_error_details is set.
3396
3397This conditional logic is all somewhat of a mess because of the odd
3398interactions between temp_details and return_error_details. One day it should
3399be re-implemented in a tidier fashion. */
3400
3401else
8768d548 3402 if (f.acl_temp_details && user_msg)
059ec3d9 3403 {
ff5929e3
JH
3404 if ( smtp_return_error_details
3405 && sender_verified_failed
3406 && sender_verified_failed->message
3407 )
a5bd321b 3408 smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message);
ff5929e3 3409
a5bd321b 3410 smtp_respond(smtp_code, codelen, TRUE, user_msg);
059ec3d9
PH
3411 }
3412 else
a5bd321b
PH
3413 smtp_respond(smtp_code, codelen, TRUE,
3414 US"Temporary local problem - please try later");
059ec3d9 3415
6ea85e9a
PH
3416/* Log the incident to the logs that are specified by log_reject_target
3417(default main, reject). This can be empty to suppress logging of rejections. If
3418the connection is not forcibly to be dropped, return 0. Otherwise, log why it
3419is closing if required and return 2. */
059ec3d9 3420
6ea85e9a 3421if (log_reject_target != 0)
887291d2 3422 {
e45a1c37 3423#ifdef SUPPORT_TLS
acec9514
JH
3424 gstring * g = s_tlslog(NULL);
3425 uschar * tls = string_from_gstring(g);
fc16abb4 3426 if (!tls) tls = US"";
e45a1c37 3427#else
fc16abb4 3428 uschar * tls = US"";
e45a1c37 3429#endif
3cc3f762
JH
3430 log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0,
3431 log_reject_target, "%s%s%s %s%srejected %s%s",
fc16abb4
JH
3432 LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"",
3433 host_and_ident(TRUE),
3434 tls,
3435 sender_info,
3436 rc == FAIL ? US"" : US"temporarily ",
3437 what, log_msg);
887291d2 3438 }
059ec3d9
PH
3439
3440if (!drop) return 0;
3441
3442log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL",
3443 smtp_get_connection_info());
8f128379
PH
3444
3445/* Run the not-quit ACL, but without any custom messages. This should not be a
3446problem, because we get here only if some other ACL has issued "drop", and
3447in that case, *its* custom messages will have been used above. */
3448
3449smtp_notquit_exit(US"acl-drop", NULL, NULL);
059ec3d9
PH
3450return 2;
3451}
3452
3453
3454
3455
3456/*************************************************
8f128379
PH
3457* Handle SMTP exit when QUIT is not given *
3458*************************************************/
3459
3460/* This function provides a logging/statistics hook for when an SMTP connection
3461is dropped on the floor or the other end goes away. It's a global function
3462because it's called from receive.c as well as this module. As well as running
3463the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
3464response, either with a custom message from the ACL, or using a default. There
3465is one case, however, when no message is output - after "drop". In that case,
3466the ACL that obeyed "drop" has already supplied the custom message, and NULL is
3467passed to this function.
3468
3469In case things go wrong while processing this function, causing an error that
4c04137d 3470may re-enter this function, there is a recursion check.
8f128379
PH
3471
3472Arguments:
3473 reason What $smtp_notquit_reason will be set to in the ACL;
3474 if NULL, the ACL is not run
3475 code The error code to return as part of the response
3476 defaultrespond The default message if there's no user_msg
3477
3478Returns: Nothing
3479*/
3480
3481void
3482smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...)
3483{
3484int rc;
3485uschar *user_msg = NULL;
3486uschar *log_msg = NULL;
3487
8c513105 3488/* Check for recursive call */
8f128379 3489
88752192 3490if (fl.smtp_exit_function_called)
8f128379
PH
3491 {
3492 log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)",
3493 reason);
3494 return;
3495 }
88752192 3496fl.smtp_exit_function_called = TRUE;
8f128379
PH
3497
3498/* Call the not-QUIT ACL, if there is one, unless no reason is given. */
3499
eea0defe 3500if (acl_smtp_notquit && reason)
8f128379
PH
3501 {
3502 smtp_notquit_reason = reason;
eea0defe
JB
3503 if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg,
3504 &log_msg)) == ERROR)
8f128379