1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Functions for handling an incoming SMTP call. */
15 /* Initialize for TCP wrappers if so configured. It appears that the macro
16 HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before
17 including that header, and restore its value afterwards. */
19 #ifdef USE_TCP_WRAPPERS
22 #define EXIM_HAVE_IPV6
28 #define HAVE_IPV6 TRUE
31 int allow_severity
= LOG_INFO
;
32 int deny_severity
= LOG_NOTICE
;
33 uschar
*tcp_wrappers_name
;
37 /* Size of buffer for reading SMTP commands. We used to use 512, as defined
38 by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
39 commands that accept arguments, and this in particular applies to AUTH, where
40 the data can be quite long. More recently this value was 2048 in Exim;
41 however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients
42 such as Thunderbird will send an AUTH with an initial-response for GSSAPI.
43 The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and
44 we need room to handle large base64-encoded AUTHs for GSSAPI.
47 #define smtp_cmd_buffer_size 16384
49 /* Size of buffer for reading SMTP incoming packets */
51 #define in_buffer_size 8192
53 /* Structure for SMTP command list */
60 short int is_mail_cmd
;
63 /* Codes for identifying commands. We order them so that those that come first
64 are those for which synchronization is always required. Checking this can help
68 /* These commands are required to be synchronized, i.e. to be the last in a
69 block of commands when pipelining. */
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 */
75 TLS_AUTH_CMD
, /* auto-command at start of SSL */
77 /* This is a dummy to identify the non-sync commands when pipelining */
79 NON_SYNC_CMD_PIPELINING
,
81 /* These commands need not be synchronized when pipelining */
83 MAIL_CMD
, RCPT_CMD
, RSET_CMD
,
85 /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and
86 processed the message is sent using a series of BDAT commands"
87 implies that BDAT should be synchronized. However, we see Google, at least,
88 sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for
89 processing of the RPCT response(s). We shall do the same, and not require
94 /* This is a dummy to identify the non-sync commands when not pipelining */
96 NON_SYNC_CMD_NON_PIPELINING
,
98 /* I have been unable to find a statement about the use of pipelining
99 with AUTH, so to be on the safe side it is here, though I kind of feel
100 it should be up there with the synchronized commands. */
104 /* I'm not sure about these, but I don't think they matter. */
109 PROXY_FAIL_IGNORE_CMD
,
112 /* These are specials that don't correspond to actual commands */
114 EOF_CMD
, OTHER_CMD
, BADARG_CMD
, BADCHAR_CMD
, BADSYN_CMD
,
115 TOO_MANY_NONMAIL_CMD
};
118 /* This is a convenience macro for adding the identity of an SMTP command
119 to the circular buffer that holds a list of the last n received. */
122 smtp_connection_had[smtp_ch_index++] = n; \
123 if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0
126 /*************************************************
127 * Local static variables *
128 *************************************************/
130 static auth_instance
*authenticated_by
;
131 static BOOL auth_advertised
;
133 static BOOL tls_advertised
;
135 static BOOL dsn_advertised
;
137 static BOOL helo_required
= FALSE
;
138 static BOOL helo_verify
= FALSE
;
139 static BOOL helo_seen
;
140 static BOOL helo_accept_junk
;
141 static BOOL count_nonmail
;
142 static BOOL pipelining_advertised
;
143 static BOOL rcpt_smtp_response_same
;
144 static BOOL rcpt_in_progress
;
145 static int nonmail_command_count
;
146 static BOOL smtp_exit_function_called
= 0;
148 static BOOL smtputf8_advertised
;
150 static int synprot_error_count
;
151 static int unknown_command_count
;
152 static int sync_cmd_limit
;
153 static int smtp_write_error
= 0;
155 static uschar
*rcpt_smtp_response
;
156 static uschar
*smtp_data_buffer
;
157 static uschar
*smtp_cmd_data
;
159 /* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their
160 final fields of all except AUTH are forced TRUE at the start of a new message
161 setup, to allow one of each between messages that is not counted as a nonmail
162 command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to
163 allow a new EHLO after starting up TLS.
165 AUTH is "falsely" labelled as a mail command initially, so that it doesn't get
166 counted. However, the flag is changed when AUTH is received, so that multiple
167 failing AUTHs will eventually hit the limit. After a successful AUTH, another
168 AUTH is already forbidden. After a TLS session is started, AUTH's flag is again
169 forced TRUE, to allow for the re-authentication that can happen at that point.
171 QUIT is also "falsely" labelled as a mail command so that it doesn't up the
172 count of non-mail commands and possibly provoke an error.
174 tls_auth is a pseudo-command, never expected in input. It is activated
175 on TLS startup and looks for a tls authenticator. */
177 static smtp_cmd_list cmd_list
[] = {
178 /* name len cmd has_arg is_mail_cmd */
180 { "rset", sizeof("rset")-1, RSET_CMD
, FALSE
, FALSE
}, /* First */
181 { "helo", sizeof("helo")-1, HELO_CMD
, TRUE
, FALSE
},
182 { "ehlo", sizeof("ehlo")-1, EHLO_CMD
, TRUE
, FALSE
},
183 { "auth", sizeof("auth")-1, AUTH_CMD
, TRUE
, TRUE
},
185 { "starttls", sizeof("starttls")-1, STARTTLS_CMD
, FALSE
, FALSE
},
186 { "tls_auth", 0, TLS_AUTH_CMD
, FALSE
, TRUE
},
189 /* If you change anything above here, also fix the definitions below. */
191 { "mail from:", sizeof("mail from:")-1, MAIL_CMD
, TRUE
, TRUE
},
192 { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD
, TRUE
, TRUE
},
193 { "data", sizeof("data")-1, DATA_CMD
, FALSE
, TRUE
},
194 { "bdat", sizeof("bdat")-1, BDAT_CMD
, TRUE
, TRUE
},
195 { "quit", sizeof("quit")-1, QUIT_CMD
, FALSE
, TRUE
},
196 { "noop", sizeof("noop")-1, NOOP_CMD
, TRUE
, FALSE
},
197 { "etrn", sizeof("etrn")-1, ETRN_CMD
, TRUE
, FALSE
},
198 { "vrfy", sizeof("vrfy")-1, VRFY_CMD
, TRUE
, FALSE
},
199 { "expn", sizeof("expn")-1, EXPN_CMD
, TRUE
, FALSE
},
200 { "help", sizeof("help")-1, HELP_CMD
, TRUE
, FALSE
}
203 static smtp_cmd_list
*cmd_list_end
=
204 cmd_list
+ sizeof(cmd_list
)/sizeof(smtp_cmd_list
);
206 #define CMD_LIST_RSET 0
207 #define CMD_LIST_HELO 1
208 #define CMD_LIST_EHLO 2
209 #define CMD_LIST_AUTH 3
210 #define CMD_LIST_STARTTLS 4
211 #define CMD_LIST_TLS_AUTH 5
213 /* This list of names is used for performing the smtp_no_mail logging action.
214 It must be kept in step with the SCH_xxx enumerations. */
216 static uschar
*smtp_names
[] =
218 US
"NONE", US
"AUTH", US
"DATA", US
"BDAT", US
"EHLO", US
"ETRN", US
"EXPN",
219 US
"HELO", US
"HELP", US
"MAIL", US
"NOOP", US
"QUIT", US
"RCPT", US
"RSET",
220 US
"STARTTLS", US
"VRFY" };
222 static uschar
*protocols_local
[] = {
223 US
"local-smtp", /* HELO */
224 US
"local-smtps", /* The rare case EHLO->STARTTLS->HELO */
225 US
"local-esmtp", /* EHLO */
226 US
"local-esmtps", /* EHLO->STARTTLS->EHLO */
227 US
"local-esmtpa", /* EHLO->AUTH */
228 US
"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
230 static uschar
*protocols
[] = {
232 US
"smtps", /* The rare case EHLO->STARTTLS->HELO */
233 US
"esmtp", /* EHLO */
234 US
"esmtps", /* EHLO->STARTTLS->EHLO */
235 US
"esmtpa", /* EHLO->AUTH */
236 US
"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */
241 #define pcrpted 1 /* added to pextend or pnormal */
242 #define pauthed 2 /* added to pextend */
244 /* Sanity check and validate optional args to MAIL FROM: envelope */
247 ENV_MAIL_OPT_SIZE
, ENV_MAIL_OPT_BODY
, ENV_MAIL_OPT_AUTH
,
251 ENV_MAIL_OPT_RET
, ENV_MAIL_OPT_ENVID
,
257 uschar
* name
; /* option requested during MAIL cmd */
258 int value
; /* enum type */
259 BOOL need_value
; /* TRUE requires value (name=value pair format)
260 FALSE is a singleton */
262 static env_mail_type_t env_mail_type_list
[] = {
263 { US
"SIZE", ENV_MAIL_OPT_SIZE
, TRUE
},
264 { US
"BODY", ENV_MAIL_OPT_BODY
, TRUE
},
265 { US
"AUTH", ENV_MAIL_OPT_AUTH
, TRUE
},
267 { US
"PRDR", ENV_MAIL_OPT_PRDR
, FALSE
},
269 { US
"RET", ENV_MAIL_OPT_RET
, TRUE
},
270 { US
"ENVID", ENV_MAIL_OPT_ENVID
, TRUE
},
272 { US
"SMTPUTF8",ENV_MAIL_OPT_UTF8
, FALSE
}, /* rfc6531 */
274 /* keep this the last entry */
275 { US
"NULL", ENV_MAIL_OPT_NULL
, FALSE
},
278 /* When reading SMTP from a remote host, we have to use our own versions of the
279 C input-reading functions, in order to be able to flush the SMTP output only
280 when about to read more data from the socket. This is the only way to get
281 optimal performance when the client is using pipelining. Flushing for every
282 command causes a separate packet and reply packet each time; saving all the
283 responses up (when pipelining) combines them into one packet and one response.
285 For simplicity, these functions are used for *all* SMTP input, not only when
286 receiving over a socket. However, after setting up a secure socket (SSL), input
287 is read via the OpenSSL library, and another set of functions is used instead
290 These functions are set in the receive_getc etc. variables and called with the
291 same interface as the C functions. However, since there can only ever be
292 one incoming SMTP call, we just use a single buffer and flags. There is no need
293 to implement a complicated private FILE-like structure.*/
295 static uschar
*smtp_inbuffer
;
296 static uschar
*smtp_inptr
;
297 static uschar
*smtp_inend
;
298 static int smtp_had_eof
;
299 static int smtp_had_error
;
302 /* forward declarations */
303 int bdat_ungetc(int ch
);
304 static int smtp_read_command(BOOL check_sync
);
305 static int synprot_error(int type
, int code
, uschar
*data
, uschar
*errmess
);
306 static void smtp_quit_handler(uschar
**, uschar
**);
307 static void smtp_rset_handler(void);
309 /*************************************************
310 * SMTP version of getc() *
311 *************************************************/
313 /* This gets the next byte from the SMTP input buffer. If the buffer is empty,
314 it flushes the output, and refills the buffer, with a timeout. The signal
315 handler is set appropriately by the calling function. This function is not used
316 after a connection has negotated itself into an TLS/SSL state.
319 Returns: the next character or EOF
325 if (smtp_inptr
>= smtp_inend
)
329 if (smtp_receive_timeout
> 0) alarm(smtp_receive_timeout
);
330 rc
= read(fileno(smtp_in
), smtp_inbuffer
, in_buffer_size
);
335 /* Must put the error text in fixed store, because this might be during
336 header reading, where it releases unused store above the header. */
339 smtp_had_error
= save_errno
;
340 smtp_read_error
= string_copy_malloc(
341 string_sprintf(" (error: %s)", strerror(save_errno
)));
343 else smtp_had_eof
= 1;
347 dkim_exim_verify_feed(smtp_inbuffer
, rc
);
349 smtp_inend
= smtp_inbuffer
+ rc
;
350 smtp_inptr
= smtp_inbuffer
;
352 return *smtp_inptr
++;
359 int n
= smtp_inend
- smtp_inptr
;
361 dkim_exim_verify_feed(smtp_inptr
, n
);
366 /* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the
367 previous BDAT chunk and getting new ones when we run out. Uses the
368 underlying smtp_getc or tls_getc both for that and for getting the
369 (buffered) data byte. EOD signals (an expected) no further data.
370 ERR signals a protocol error, and EOF a closed input stream.
372 Called from read_bdat_smtp() in receive.c for the message body, but also
373 by the headers read loop in receive_msg(); manipulates chunking_state
374 to handle the BDAT command/response.
375 Placed here due to the correlation with the above smtp_getc(), which it wraps,
376 and also by the need to do smtp command/response handling.
379 Returns: the next character or ERR, EOD or EOF
385 uschar
* user_msg
= NULL
;
390 if (chunking_data_left
-- > 0)
391 return lwr_receive_getc();
393 receive_getc
= lwr_receive_getc
;
394 receive_ungetc
= lwr_receive_ungetc
;
396 /* If not the last, ack the received chunk. The last response is delayed
397 until after the data ACL decides on it */
399 if (chunking_state
== CHUNKING_LAST
)
402 dkim_exim_verify_feed(NULL
, 0); /* notify EOD */
407 chunking_state
= CHUNKING_OFFERED
;
408 smtp_printf("250 %u byte chunk received\r\n", chunking_datasize
);
410 /* Expect another BDAT cmd from input. RFC 3030 says nothing about
411 QUIT, RSET or NOOP but handling them seems obvious */
414 switch(smtp_read_command(TRUE
))
417 (void) synprot_error(L_smtp_protocol_error
, 503, NULL
,
418 US
"only BDAT permissible after non-LAST BDAT");
421 switch(smtp_read_command(TRUE
))
423 case QUIT_CMD
: smtp_quit_handler(&user_msg
, &log_msg
); /*FALLTHROUGH */
424 case EOF_CMD
: return EOF
;
425 case RSET_CMD
: smtp_rset_handler(); return ERR
;
426 default: if (synprot_error(L_smtp_protocol_error
, 503, NULL
,
427 US
"only RSET accepted now") > 0)
429 goto repeat_until_rset
;
433 smtp_quit_handler(&user_msg
, &log_msg
);
444 smtp_printf("250 OK\r\n");
451 if (sscanf(CS smtp_cmd_data
, "%u %n", &chunking_datasize
, &n
) < 1)
453 (void) synprot_error(L_smtp_protocol_error
, 501, NULL
,
454 US
"missing size for BDAT command");
457 chunking_state
= strcmpic(smtp_cmd_data
+n
, US
"LAST") == 0
458 ? CHUNKING_LAST
: CHUNKING_ACTIVE
;
459 chunking_data_left
= chunking_datasize
;
461 if (chunking_datasize
== 0)
462 if (chunking_state
== CHUNKING_LAST
)
466 (void) synprot_error(L_smtp_protocol_error
, 504, NULL
,
467 US
"zero size for BDAT command");
468 goto repeat_until_rset
;
471 receive_getc
= bdat_getc
;
472 receive_ungetc
= bdat_ungetc
;
473 break; /* to top of main loop */
480 bdat_flush_data(void)
482 while (chunking_data_left
-- > 0)
483 if (lwr_receive_getc() < 0)
486 receive_getc
= lwr_receive_getc
;
487 receive_ungetc
= lwr_receive_ungetc
;
489 if (chunking_state
!= CHUNKING_LAST
)
490 chunking_state
= CHUNKING_OFFERED
;
496 /*************************************************
497 * SMTP version of ungetc() *
498 *************************************************/
500 /* Puts a character back in the input buffer. Only ever
506 Returns: the character
520 chunking_data_left
++;
521 return lwr_receive_ungetc(ch
);
526 /*************************************************
527 * SMTP version of feof() *
528 *************************************************/
530 /* Tests for a previous EOF
533 Returns: non-zero if the eof flag is set
545 /*************************************************
546 * SMTP version of ferror() *
547 *************************************************/
549 /* Tests for a previous read error, and returns with errno
550 restored to what it was when the error was detected.
553 Returns: non-zero if the error flag is set
559 errno
= smtp_had_error
;
560 return smtp_had_error
;
565 /*************************************************
566 * Test for characters in the SMTP buffer *
567 *************************************************/
569 /* Used at the end of a message
578 return smtp_inptr
< smtp_inend
;
583 /*************************************************
584 * Write formatted string to SMTP channel *
585 *************************************************/
587 /* This is a separate function so that we don't have to repeat everything for
588 TLS support or debugging. It is global so that the daemon and the
589 authentication functions can use it. It does not return any error indication,
590 because major problems such as dropped connections won't show up till an output
591 flush for non-TLS connections. The smtp_fflush() function is available for
592 checking that: for convenience, TLS output errors are remembered here so that
593 they are also picked up later by smtp_fflush().
597 ... optional arguments
603 smtp_printf(const char *format
, ...)
607 va_start(ap
, format
);
608 smtp_vprintf(format
, ap
);
612 /* This is split off so that verify.c:respond_printf() can, in effect, call
613 smtp_printf(), bearing in mind that in C a vararg function can't directly
614 call another vararg function, only a function which accepts a va_list. */
617 smtp_vprintf(const char *format
, va_list ap
)
621 yield
= string_vformat(big_buffer
, big_buffer_size
, format
, ap
);
625 void *reset_point
= store_get(0);
626 uschar
*msg_copy
, *cr
, *end
;
627 msg_copy
= string_copy(big_buffer
);
628 end
= msg_copy
+ Ustrlen(msg_copy
);
629 while ((cr
= Ustrchr(msg_copy
, '\r')) != NULL
) /* lose CRs */
630 memmove(cr
, cr
+ 1, (end
--) - cr
);
631 debug_printf("SMTP>> %s", msg_copy
);
632 store_reset(reset_point
);
637 log_write(0, LOG_MAIN
|LOG_PANIC
, "string too large in smtp_printf()");
638 smtp_closedown(US
"Unexpected error");
639 exim_exit(EXIT_FAILURE
);
642 /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
643 have had the same. Note: this code is also present in smtp_respond(). It would
644 be tidier to have it only in one place, but when it was added, it was easier to
645 do it that way, so as not to have to mess with the code for the RCPT command,
646 which sometimes uses smtp_printf() and sometimes smtp_respond(). */
648 if (rcpt_in_progress
)
650 if (rcpt_smtp_response
== NULL
)
651 rcpt_smtp_response
= string_copy(big_buffer
);
652 else if (rcpt_smtp_response_same
&&
653 Ustrcmp(rcpt_smtp_response
, big_buffer
) != 0)
654 rcpt_smtp_response_same
= FALSE
;
655 rcpt_in_progress
= FALSE
;
658 /* Now write the string */
661 if (tls_in
.active
>= 0)
663 if (tls_write(TRUE
, big_buffer
, Ustrlen(big_buffer
)) < 0)
664 smtp_write_error
= -1;
669 if (fprintf(smtp_out
, "%s", big_buffer
) < 0) smtp_write_error
= -1;
674 /*************************************************
675 * Flush SMTP out and check for error *
676 *************************************************/
678 /* This function isn't currently used within Exim (it detects errors when it
679 tries to read the next SMTP input), but is available for use in local_scan().
680 For non-TLS connections, it flushes the output and checks for errors. For
681 TLS-connections, it checks for a previously-detected TLS write error.
684 Returns: 0 for no error; -1 after an error
690 if (tls_in
.active
< 0 && fflush(smtp_out
) != 0) smtp_write_error
= -1;
691 return smtp_write_error
;
696 /*************************************************
697 * SMTP command read timeout *
698 *************************************************/
700 /* Signal handler for timing out incoming SMTP commands. This attempts to
703 Argument: signal number (SIGALRM)
708 command_timeout_handler(int sig
)
710 sig
= sig
; /* Keep picky compilers happy */
711 log_write(L_lost_incoming_connection
,
712 LOG_MAIN
, "SMTP command timeout on%s connection from %s",
713 (tls_in
.active
>= 0)? " TLS" : "",
714 host_and_ident(FALSE
));
715 if (smtp_batched_input
)
716 moan_smtp_batch(NULL
, "421 SMTP command timeout"); /* Does not return */
717 smtp_notquit_exit(US
"command-timeout", US
"421",
718 US
"%s: SMTP command timeout - closing connection", smtp_active_hostname
);
719 exim_exit(EXIT_FAILURE
);
724 /*************************************************
726 *************************************************/
728 /* Signal handler for handling SIGTERM. Again, try to finish tidily.
730 Argument: signal number (SIGTERM)
735 command_sigterm_handler(int sig
)
737 sig
= sig
; /* Keep picky compilers happy */
738 log_write(0, LOG_MAIN
, "%s closed after SIGTERM", smtp_get_connection_info());
739 if (smtp_batched_input
)
740 moan_smtp_batch(NULL
, "421 SIGTERM received"); /* Does not return */
741 smtp_notquit_exit(US
"signal-exit", US
"421",
742 US
"%s: Service not available - closing connection", smtp_active_hostname
);
743 exim_exit(EXIT_FAILURE
);
750 /*************************************************
751 * Restore socket timeout to previous value *
752 *************************************************/
753 /* If the previous value was successfully retrieved, restore
754 it before returning control to the non-proxy routines
756 Arguments: fd - File descriptor for input
757 get_ok - Successfully retrieved previous values
758 tvtmp - Time struct with previous values
759 vslen - Length of time struct
763 restore_socket_timeout(int fd
, int get_ok
, struct timeval tvtmp
, socklen_t vslen
)
766 setsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tvtmp
, vslen
);
769 /*************************************************
770 * Check if host is required proxy host *
771 *************************************************/
772 /* The function determines if inbound host will be a regular smtp host
773 or if it is configured that it must use Proxy Protocol.
780 check_proxy_protocol_host()
783 /* Cannot configure local connection as a proxy inbound */
784 if (sender_host_address
== NULL
) return proxy_session
;
786 rc
= verify_check_this_host(CUSS
&hosts_proxy
, NULL
, NULL
,
787 sender_host_address
, NULL
);
791 debug_printf("Detected proxy protocol configured host\n");
792 proxy_session
= TRUE
;
794 return proxy_session
;
798 /*************************************************
799 * Setup host for proxy protocol *
800 *************************************************/
801 /* The function configures the connection based on a header from the
802 inbound host to use Proxy Protocol. The specification is very exact
803 so exit with an error if do not find the exact required pieces. This
804 includes an incorrect number of spaces separating args.
811 setup_proxy_protocol_host()
823 struct { /* TCP/UDP over IPv4, len = 12 */
829 struct { /* TCP/UDP over IPv6, len = 36 */
830 uint8_t src_addr
[16];
831 uint8_t dst_addr
[16];
835 struct { /* AF_UNIX sockets, len = 216 */
836 uschar src_addr
[108];
837 uschar dst_addr
[108];
843 /* Temp variables used in PPv2 address:port parsing */
845 char tmpip
[INET_ADDRSTRLEN
];
846 struct sockaddr_in tmpaddr
;
847 char tmpip6
[INET6_ADDRSTRLEN
];
848 struct sockaddr_in6 tmpaddr6
;
852 const char v2sig
[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
853 uschar
*iptype
; /* To display debug info */
856 struct timeval tvtmp
;
858 vslen
= sizeof(struct timeval
);
860 fd
= fileno(smtp_in
);
862 /* Save current socket timeout values */
863 get_ok
= getsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tvtmp
,
866 /* Proxy Protocol host must send header within a short time
867 (default 3 seconds) or it's considered invalid */
868 tv
.tv_sec
= PROXY_NEGOTIATION_TIMEOUT_SEC
;
869 tv
.tv_usec
= PROXY_NEGOTIATION_TIMEOUT_USEC
;
870 setsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tv
,
871 sizeof(struct timeval
));
875 /* The inbound host was declared to be a Proxy Protocol host, so
876 don't do a PEEK into the data, actually slurp it up. */
877 ret
= recv(fd
, &hdr
, sizeof(hdr
), 0);
879 while (ret
== -1 && errno
== EINTR
);
883 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
884 return (errno
== EAGAIN
) ? 0 : ERRNO_PROXYFAIL
;
888 memcmp(&hdr
.v2
, v2sig
, 12) == 0)
892 /* May 2014: haproxy combined the version and command into one byte to
893 allow two full bytes for the length field in order to proxy SSL
894 connections. SSL Proxy is not supported in this version of Exim, but
895 must still seperate values here. */
896 ver
= (hdr
.v2
.ver_cmd
& 0xf0) >> 4;
897 cmd
= (hdr
.v2
.ver_cmd
& 0x0f);
901 DEBUG(D_receive
) debug_printf("Invalid Proxy Protocol version: %d\n", ver
);
904 DEBUG(D_receive
) debug_printf("Detected PROXYv2 header\n");
905 /* The v2 header will always be 16 bytes per the spec. */
906 size
= 16 + hdr
.v2
.len
;
909 DEBUG(D_receive
) debug_printf("Truncated or too large PROXYv2 header (%d/%d)\n",
915 case 0x01: /* PROXY command */
918 case 0x11: /* TCPv4 address type */
920 tmpaddr
.sin_addr
.s_addr
= hdr
.v2
.addr
.ip4
.src_addr
;
921 inet_ntop(AF_INET
, &(tmpaddr
.sin_addr
), (char *)&tmpip
, sizeof(tmpip
));
922 if (!string_is_ip_address(US tmpip
,NULL
))
924 DEBUG(D_receive
) debug_printf("Invalid %s source IP\n", iptype
);
925 return ERRNO_PROXYFAIL
;
927 proxy_local_address
= sender_host_address
;
928 sender_host_address
= string_copy(US tmpip
);
929 tmpport
= ntohs(hdr
.v2
.addr
.ip4
.src_port
);
930 proxy_local_port
= sender_host_port
;
931 sender_host_port
= tmpport
;
932 /* Save dest ip/port */
933 tmpaddr
.sin_addr
.s_addr
= hdr
.v2
.addr
.ip4
.dst_addr
;
934 inet_ntop(AF_INET
, &(tmpaddr
.sin_addr
), (char *)&tmpip
, sizeof(tmpip
));
935 if (!string_is_ip_address(US tmpip
,NULL
))
937 DEBUG(D_receive
) debug_printf("Invalid %s dest port\n", iptype
);
938 return ERRNO_PROXYFAIL
;
940 proxy_external_address
= string_copy(US tmpip
);
941 tmpport
= ntohs(hdr
.v2
.addr
.ip4
.dst_port
);
942 proxy_external_port
= tmpport
;
944 case 0x21: /* TCPv6 address type */
946 memmove(tmpaddr6
.sin6_addr
.s6_addr
, hdr
.v2
.addr
.ip6
.src_addr
, 16);
947 inet_ntop(AF_INET6
, &(tmpaddr6
.sin6_addr
), (char *)&tmpip6
, sizeof(tmpip6
));
948 if (!string_is_ip_address(US tmpip6
,NULL
))
950 DEBUG(D_receive
) debug_printf("Invalid %s source IP\n", iptype
);
951 return ERRNO_PROXYFAIL
;
953 proxy_local_address
= sender_host_address
;
954 sender_host_address
= string_copy(US tmpip6
);
955 tmpport
= ntohs(hdr
.v2
.addr
.ip6
.src_port
);
956 proxy_local_port
= sender_host_port
;
957 sender_host_port
= tmpport
;
958 /* Save dest ip/port */
959 memmove(tmpaddr6
.sin6_addr
.s6_addr
, hdr
.v2
.addr
.ip6
.dst_addr
, 16);
960 inet_ntop(AF_INET6
, &(tmpaddr6
.sin6_addr
), (char *)&tmpip6
, sizeof(tmpip6
));
961 if (!string_is_ip_address(US tmpip6
,NULL
))
963 DEBUG(D_receive
) debug_printf("Invalid %s dest port\n", iptype
);
964 return ERRNO_PROXYFAIL
;
966 proxy_external_address
= string_copy(US tmpip6
);
967 tmpport
= ntohs(hdr
.v2
.addr
.ip6
.dst_port
);
968 proxy_external_port
= tmpport
;
972 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
976 /* Unsupported protocol, keep local connection address */
978 case 0x00: /* LOCAL command */
979 /* Keep local connection address for LOCAL */
983 debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd
);
988 memcmp(hdr
.v1
.line
, "PROXY", 5) == 0)
990 uschar
*p
= string_copy(hdr
.v1
.line
);
991 uschar
*end
= memchr(p
, '\r', ret
- 1);
992 uschar
*sp
; /* Utility variables follow */
996 if (!end
|| end
[1] != '\n')
998 DEBUG(D_receive
) debug_printf("Partial or invalid PROXY header\n");
1001 *end
= '\0'; /* Terminate the string */
1002 size
= end
+ 2 - hdr
.v1
.line
; /* Skip header + CRLF */
1003 DEBUG(D_receive
) debug_printf("Detected PROXYv1 header\n");
1004 /* Step through the string looking for the required fields. Ensure
1005 strict adherance to required formatting, exit for any error. */
1007 if (!isspace(*(p
++)))
1009 DEBUG(D_receive
) debug_printf("Missing space after PROXY command\n");
1012 if (!Ustrncmp(p
, CCS
"TCP4", 4))
1014 else if (!Ustrncmp(p
,CCS
"TCP6", 4))
1016 else if (!Ustrncmp(p
,CCS
"UNKNOWN", 7))
1018 iptype
= US
"Unknown";
1023 DEBUG(D_receive
) debug_printf("Invalid TCP type\n");
1027 p
+= Ustrlen(iptype
);
1028 if (!isspace(*(p
++)))
1030 DEBUG(D_receive
) debug_printf("Missing space after TCP4/6 command\n");
1033 /* Find the end of the arg */
1034 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1037 debug_printf("Did not find proxied src %s\n", iptype
);
1041 if(!string_is_ip_address(p
,NULL
))
1044 debug_printf("Proxied src arg is not an %s address\n", iptype
);
1047 proxy_local_address
= sender_host_address
;
1048 sender_host_address
= p
;
1050 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1053 debug_printf("Did not find proxy dest %s\n", iptype
);
1057 if(!string_is_ip_address(p
,NULL
))
1060 debug_printf("Proxy dest arg is not an %s address\n", iptype
);
1063 proxy_external_address
= p
;
1065 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1067 DEBUG(D_receive
) debug_printf("Did not find proxied src port\n");
1071 tmp_port
= strtol(CCS p
,&endc
,10);
1072 if (*endc
|| tmp_port
== 0)
1075 debug_printf("Proxied src port '%s' not an integer\n", p
);
1078 proxy_local_port
= sender_host_port
;
1079 sender_host_port
= tmp_port
;
1081 if ((sp
= Ustrchr(p
, '\0')) == NULL
)
1083 DEBUG(D_receive
) debug_printf("Did not find proxy dest port\n");
1086 tmp_port
= strtol(CCS p
,&endc
,10);
1087 if (*endc
|| tmp_port
== 0)
1090 debug_printf("Proxy dest port '%s' not an integer\n", p
);
1093 proxy_external_port
= tmp_port
;
1094 /* Already checked for /r /n above. Good V1 header received. */
1099 /* Wrong protocol */
1100 DEBUG(D_receive
) debug_printf("Invalid proxy protocol version negotiation\n");
1105 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
1106 /* Don't flush any potential buffer contents. Any input should cause a
1107 synchronization failure */
1111 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
1113 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype
);
1114 return proxy_session
;
1118 /*************************************************
1119 * Read one command line *
1120 *************************************************/
1122 /* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
1123 There are sites that don't do this, and in any case internal SMTP probably
1124 should check only for LF. Consequently, we check here for LF only. The line
1125 ends up with [CR]LF removed from its end. If we get an overlong line, treat as
1126 an unknown command. The command is read into the global smtp_cmd_buffer so that
1127 it is available via $smtp_command.
1129 The character reading routine sets up a timeout for each block actually read
1130 from the input (which may contain more than one command). We set up a special
1131 signal handler that closes down the session on a timeout. Control does not
1132 return when it runs.
1135 check_sync if TRUE, check synchronization rules if global option is TRUE
1137 Returns: a code identifying the command (enumerated above)
1141 smtp_read_command(BOOL check_sync
)
1146 BOOL hadnull
= FALSE
;
1148 os_non_restarting_signal(SIGALRM
, command_timeout_handler
);
1150 while ((c
= (receive_getc
)()) != '\n' && c
!= EOF
)
1152 if (ptr
>= smtp_cmd_buffer_size
)
1154 os_non_restarting_signal(SIGALRM
, sigalrm_handler
);
1162 smtp_cmd_buffer
[ptr
++] = c
;
1165 receive_linecount
++; /* For BSMTP errors */
1166 os_non_restarting_signal(SIGALRM
, sigalrm_handler
);
1168 /* If hit end of file, return pseudo EOF command. Whether we have a
1169 part-line already read doesn't matter, since this is an error state. */
1171 if (c
== EOF
) return EOF_CMD
;
1173 /* Remove any CR and white space at the end of the line, and terminate the
1176 while (ptr
> 0 && isspace(smtp_cmd_buffer
[ptr
-1])) ptr
--;
1177 smtp_cmd_buffer
[ptr
] = 0;
1179 DEBUG(D_receive
) debug_printf("SMTP<< %s\n", smtp_cmd_buffer
);
1181 /* NULLs are not allowed in SMTP commands */
1183 if (hadnull
) return BADCHAR_CMD
;
1185 /* Scan command list and return identity, having set the data pointer
1186 to the start of the actual data characters. Check for SMTP synchronization
1189 for (p
= cmd_list
; p
< cmd_list_end
; p
++)
1191 #ifdef SUPPORT_PROXY
1192 /* Only allow QUIT command if Proxy Protocol parsing failed */
1193 if (proxy_session
&& proxy_session_failed
)
1195 if (p
->cmd
!= QUIT_CMD
)
1200 && strncmpic(smtp_cmd_buffer
, US p
->name
, p
->len
) == 0
1201 && ( smtp_cmd_buffer
[p
->len
-1] == ':' /* "mail from:" or "rcpt to:" */
1202 || smtp_cmd_buffer
[p
->len
] == 0
1203 || smtp_cmd_buffer
[p
->len
] == ' '
1206 if (smtp_inptr
< smtp_inend
&& /* Outstanding input */
1207 p
->cmd
< sync_cmd_limit
&& /* Command should sync */
1208 check_sync
&& /* Local flag set */
1209 smtp_enforce_sync
&& /* Global flag set */
1210 sender_host_address
!= NULL
&& /* Not local input */
1211 !sender_host_notsocket
) /* Really is a socket */
1214 /* The variables $smtp_command and $smtp_command_argument point into the
1215 unmodified input buffer. A copy of the latter is taken for actual
1216 processing, so that it can be chopped up into separate parts if necessary,
1217 for example, when processing a MAIL command options such as SIZE that can
1218 follow the sender address. */
1220 smtp_cmd_argument
= smtp_cmd_buffer
+ p
->len
;
1221 while (isspace(*smtp_cmd_argument
)) smtp_cmd_argument
++;
1222 Ustrcpy(smtp_data_buffer
, smtp_cmd_argument
);
1223 smtp_cmd_data
= smtp_data_buffer
;
1225 /* Count non-mail commands from those hosts that are controlled in this
1226 way. The default is all hosts. We don't waste effort checking the list
1227 until we get a non-mail command, but then cache the result to save checking
1228 again. If there's a DEFER while checking the host, assume it's in the list.
1230 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1231 start of each incoming message by fiddling with the value in the table. */
1233 if (!p
->is_mail_cmd
)
1235 if (count_nonmail
== TRUE_UNSET
) count_nonmail
=
1236 verify_check_host(&smtp_accept_max_nonmail_hosts
) != FAIL
;
1237 if (count_nonmail
&& ++nonmail_command_count
> smtp_accept_max_nonmail
)
1238 return TOO_MANY_NONMAIL_CMD
;
1241 /* If there is data for a command that does not expect it, generate the
1244 return (p
->has_arg
|| *smtp_cmd_data
== 0)? p
->cmd
: BADARG_CMD
;
1248 #ifdef SUPPORT_PROXY
1249 /* Only allow QUIT command if Proxy Protocol parsing failed */
1250 if (proxy_session
&& proxy_session_failed
)
1251 return PROXY_FAIL_IGNORE_CMD
;
1254 /* Enforce synchronization for unknown commands */
1256 if (smtp_inptr
< smtp_inend
&& /* Outstanding input */
1257 check_sync
&& /* Local flag set */
1258 smtp_enforce_sync
&& /* Global flag set */
1259 sender_host_address
!= NULL
&& /* Not local input */
1260 !sender_host_notsocket
) /* Really is a socket */
1268 /*************************************************
1269 * Recheck synchronization *
1270 *************************************************/
1272 /* Synchronization checks can never be perfect because a packet may be on its
1273 way but not arrived when the check is done. Such checks can in any case only be
1274 done when TLS is not in use. Normally, the checks happen when commands are
1275 read: Exim ensures that there is no more input in the input buffer. In normal
1276 cases, the response to the command will be fast, and there is no further check.
1278 However, for some commands an ACL is run, and that can include delays. In those
1279 cases, it is useful to do another check on the input just before sending the
1280 response. This also applies at the start of a connection. This function does
1281 that check by means of the select() function, as long as the facility is not
1282 disabled or inappropriate. A failure of select() is ignored.
1284 When there is unwanted input, we read it so that it appears in the log of the
1288 Returns: TRUE if all is well; FALSE if there is input pending
1296 struct timeval tzero
;
1298 if (!smtp_enforce_sync
|| sender_host_address
== NULL
||
1299 sender_host_notsocket
|| tls_in
.active
>= 0)
1302 fd
= fileno(smtp_in
);
1307 rc
= select(fd
+ 1, (SELECT_ARG2_TYPE
*)&fds
, NULL
, NULL
, &tzero
);
1309 if (rc
<= 0) return TRUE
; /* Not ready to read */
1311 if (rc
< 0) return TRUE
; /* End of file or error */
1314 rc
= smtp_inend
- smtp_inptr
;
1315 if (rc
> 150) rc
= 150;
1322 /*************************************************
1323 * Forced closedown of call *
1324 *************************************************/
1326 /* This function is called from log.c when Exim is dying because of a serious
1327 disaster, and also from some other places. If an incoming non-batched SMTP
1328 channel is open, it swallows the rest of the incoming message if in the DATA
1329 phase, sends the reply string, and gives an error to all subsequent commands
1330 except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1334 message SMTP reply string to send, excluding the code
1340 smtp_closedown(uschar
*message
)
1342 if (smtp_in
== NULL
|| smtp_batched_input
) return;
1343 receive_swallow_smtp();
1344 smtp_printf("421 %s\r\n", message
);
1348 switch(smtp_read_command(FALSE
))
1354 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
1359 smtp_printf("250 Reset OK\r\n");
1363 smtp_printf("421 %s\r\n", message
);
1372 /*************************************************
1373 * Set up connection info for logging *
1374 *************************************************/
1376 /* This function is called when logging information about an SMTP connection.
1377 It sets up appropriate source information, depending on the type of connection.
1378 If sender_fullhost is NULL, we are at a very early stage of the connection;
1379 just use the IP address.
1382 Returns: a string describing the connection
1386 smtp_get_connection_info(void)
1388 uschar
*hostname
= (sender_fullhost
== NULL
)?
1389 sender_host_address
: sender_fullhost
;
1392 return string_sprintf("SMTP connection from %s", hostname
);
1394 if (sender_host_unknown
|| sender_host_notsocket
)
1395 return string_sprintf("SMTP connection from %s", sender_ident
);
1398 return string_sprintf("SMTP connection from %s (via inetd)", hostname
);
1400 if (LOGGING(incoming_interface
) && interface_address
!= NULL
)
1401 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname
,
1402 interface_address
, interface_port
);
1404 return string_sprintf("SMTP connection from %s", hostname
);
1410 /* Append TLS-related information to a log line
1413 s String under construction: allocated string to extend, or NULL
1414 sizep Pointer to current allocation size (update on return), or NULL
1415 ptrp Pointer to index for new entries in string (update on return), or NULL
1417 Returns: Allocated string or NULL
1420 s_tlslog(uschar
* s
, int * sizep
, int * ptrp
)
1422 int size
= sizep
? *sizep
: 0;
1423 int ptr
= ptrp
? *ptrp
: 0;
1425 if (LOGGING(tls_cipher
) && tls_in
.cipher
!= NULL
)
1426 s
= string_append(s
, &size
, &ptr
, 2, US
" X=", tls_in
.cipher
);
1427 if (LOGGING(tls_certificate_verified
) && tls_in
.cipher
!= NULL
)
1428 s
= string_append(s
, &size
, &ptr
, 2, US
" CV=",
1429 tls_in
.certificate_verified
? "yes":"no");
1430 if (LOGGING(tls_peerdn
) && tls_in
.peerdn
!= NULL
)
1431 s
= string_append(s
, &size
, &ptr
, 3, US
" DN=\"",
1432 string_printing(tls_in
.peerdn
), US
"\"");
1433 if (LOGGING(tls_sni
) && tls_in
.sni
!= NULL
)
1434 s
= string_append(s
, &size
, &ptr
, 3, US
" SNI=\"",
1435 string_printing(tls_in
.sni
), US
"\"");
1440 if (sizep
) *sizep
= size
;
1441 if (ptrp
) *ptrp
= ptr
;
1447 /*************************************************
1448 * Log lack of MAIL if so configured *
1449 *************************************************/
1451 /* This function is called when an SMTP session ends. If the log selector
1452 smtp_no_mail is set, write a log line giving some details of what has happened
1453 in the SMTP session.
1460 smtp_log_no_mail(void)
1465 if (smtp_mailcmd_count
> 0 || !LOGGING(smtp_no_mail
))
1471 if (sender_host_authenticated
!= NULL
)
1473 s
= string_append(s
, &size
, &ptr
, 2, US
" A=", sender_host_authenticated
);
1474 if (authenticated_id
!= NULL
)
1475 s
= string_append(s
, &size
, &ptr
, 2, US
":", authenticated_id
);
1479 s
= s_tlslog(s
, &size
, &ptr
);
1482 sep
= (smtp_connection_had
[SMTP_HBUFF_SIZE
-1] != SCH_NONE
)?
1483 US
" C=..." : US
" C=";
1484 for (i
= smtp_ch_index
; i
< SMTP_HBUFF_SIZE
; i
++)
1486 if (smtp_connection_had
[i
] != SCH_NONE
)
1488 s
= string_append(s
, &size
, &ptr
, 2, sep
,
1489 smtp_names
[smtp_connection_had
[i
]]);
1494 for (i
= 0; i
< smtp_ch_index
; i
++)
1496 s
= string_append(s
, &size
, &ptr
, 2, sep
, smtp_names
[smtp_connection_had
[i
]]);
1500 if (s
!= NULL
) s
[ptr
] = 0; else s
= US
"";
1501 log_write(0, LOG_MAIN
, "no MAIL in SMTP connection from %s D=%s%s",
1502 host_and_ident(FALSE
),
1503 readconf_printtime( (int) ((long)time(NULL
) - (long)smtp_connection_start
)),
1509 /*************************************************
1510 * Check HELO line and set sender_helo_name *
1511 *************************************************/
1513 /* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1514 the domain name of the sending host, or an ip literal in square brackets. The
1515 arrgument is placed in sender_helo_name, which is in malloc store, because it
1516 must persist over multiple incoming messages. If helo_accept_junk is set, this
1517 host is permitted to send any old junk (needed for some broken hosts).
1518 Otherwise, helo_allow_chars can be used for rogue characters in general
1519 (typically people want to let in underscores).
1522 s the data portion of the line (already past any white space)
1524 Returns: TRUE or FALSE
1528 check_helo(uschar
*s
)
1531 uschar
*end
= s
+ Ustrlen(s
);
1532 BOOL yield
= helo_accept_junk
;
1534 /* Discard any previous helo name */
1536 if (sender_helo_name
!= NULL
)
1538 store_free(sender_helo_name
);
1539 sender_helo_name
= NULL
;
1542 /* Skip tests if junk is permitted. */
1546 /* Allow the new standard form for IPv6 address literals, namely,
1547 [IPv6:....], and because someone is bound to use it, allow an equivalent
1548 IPv4 form. Allow plain addresses as well. */
1555 if (strncmpic(s
, US
"[IPv6:", 6) == 0)
1556 yield
= (string_is_ip_address(s
+6, NULL
) == 6);
1557 else if (strncmpic(s
, US
"[IPv4:", 6) == 0)
1558 yield
= (string_is_ip_address(s
+6, NULL
) == 4);
1560 yield
= (string_is_ip_address(s
+1, NULL
) != 0);
1565 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1566 that have been configured (usually underscore - sigh). */
1573 if (!isalnum(*s
) && *s
!= '.' && *s
!= '-' &&
1574 Ustrchr(helo_allow_chars
, *s
) == NULL
)
1584 /* Save argument if OK */
1586 if (yield
) sender_helo_name
= string_copy_malloc(start
);
1594 /*************************************************
1595 * Extract SMTP command option *
1596 *************************************************/
1598 /* This function picks the next option setting off the end of smtp_cmd_data. It
1599 is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1600 things that can appear there.
1603 name point this at the name
1604 value point this at the data string
1606 Returns: TRUE if found an option
1610 extract_option(uschar
**name
, uschar
**value
)
1613 uschar
*v
= smtp_cmd_data
+ Ustrlen(smtp_cmd_data
) - 1;
1614 while (isspace(*v
)) v
--;
1616 while (v
> smtp_cmd_data
&& *v
!= '=' && !isspace(*v
)) v
--;
1621 while(isalpha(n
[-1])) n
--;
1622 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
1623 if (!isspace(n
[-1])) return FALSE
;
1629 if (v
== smtp_cmd_data
) return FALSE
;
1641 /*************************************************
1642 * Reset for new message *
1643 *************************************************/
1645 /* This function is called whenever the SMTP session is reset from
1646 within either of the setup functions.
1648 Argument: the stacking pool storage reset point
1653 smtp_reset(void *reset_point
)
1655 store_reset(reset_point
);
1656 recipients_list
= NULL
;
1657 rcpt_count
= rcpt_defer_count
= rcpt_fail_count
=
1658 raw_recipients_count
= recipients_count
= recipients_list_max
= 0;
1659 cancel_cutthrough_connection("smtp reset");
1660 message_linecount
= 0;
1662 acl_added_headers
= NULL
;
1663 acl_removed_headers
= NULL
;
1664 queue_only_policy
= FALSE
;
1665 rcpt_smtp_response
= NULL
;
1666 rcpt_smtp_response_same
= TRUE
;
1667 rcpt_in_progress
= FALSE
;
1668 deliver_freeze
= FALSE
; /* Can be set by ACL */
1669 freeze_tell
= freeze_tell_config
; /* Can be set by ACL */
1670 fake_response
= OK
; /* Can be set by ACL */
1671 #ifdef WITH_CONTENT_SCAN
1672 no_mbox_unspool
= FALSE
; /* Can be set by ACL */
1674 submission_mode
= FALSE
; /* Can be set by ACL */
1675 suppress_local_fixups
= suppress_local_fixups_default
; /* Can be set by ACL */
1676 active_local_from_check
= local_from_check
; /* Can be set by ACL */
1677 active_local_sender_retain
= local_sender_retain
; /* Can be set by ACL */
1678 sender_address
= NULL
;
1679 submission_name
= NULL
; /* Can be set by ACL */
1680 raw_sender
= NULL
; /* After SMTP rewrite, before qualifying */
1681 sender_address_unrewritten
= NULL
; /* Set only after verify rewrite */
1682 sender_verified_list
= NULL
; /* No senders verified */
1683 memset(sender_address_cache
, 0, sizeof(sender_address_cache
));
1684 memset(sender_domain_cache
, 0, sizeof(sender_domain_cache
));
1686 authenticated_sender
= NULL
;
1687 #ifdef EXPERIMENTAL_BRIGHTMAIL
1689 bmi_verdicts
= NULL
;
1691 #ifndef DISABLE_DKIM
1692 dkim_signers
= NULL
;
1693 dkim_disable_verify
= FALSE
;
1694 dkim_collect_input
= FALSE
;
1698 #ifndef DISABLE_PRDR
1699 prdr_requested
= FALSE
;
1701 #ifdef EXPERIMENTAL_SPF
1702 spf_header_comment
= NULL
;
1703 spf_received
= NULL
;
1705 spf_smtp_comment
= NULL
;
1708 message_smtputf8
= FALSE
;
1710 body_linecount
= body_zerocount
= 0;
1712 sender_rate
= sender_rate_limit
= sender_rate_period
= NULL
;
1713 ratelimiters_mail
= NULL
; /* Updated by ratelimit ACL condition */
1714 /* Note that ratelimiters_conn persists across resets. */
1716 /* Reset message ACL variables */
1720 /* The message body variables use malloc store. They may be set if this is
1721 not the first message in an SMTP session and the previous message caused them
1722 to be referenced in an ACL. */
1724 if (message_body
!= NULL
)
1726 store_free(message_body
);
1727 message_body
= NULL
;
1730 if (message_body_end
!= NULL
)
1732 store_free(message_body_end
);
1733 message_body_end
= NULL
;
1736 /* Warning log messages are also saved in malloc store. They are saved to avoid
1737 repetition in the same message, but it seems right to repeat them for different
1740 while (acl_warn_logged
!= NULL
)
1742 string_item
*this = acl_warn_logged
;
1743 acl_warn_logged
= acl_warn_logged
->next
;
1752 /*************************************************
1753 * Initialize for incoming batched SMTP message *
1754 *************************************************/
1756 /* This function is called from smtp_setup_msg() in the case when
1757 smtp_batched_input is true. This happens when -bS is used to pass a whole batch
1758 of messages in one file with SMTP commands between them. All errors must be
1759 reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
1760 relevant. After an error on a sender, or an invalid recipient, the remainder
1761 of the message is skipped. The value of received_protocol is already set.
1764 Returns: > 0 message successfully started (reached DATA)
1765 = 0 QUIT read or end of file reached
1766 < 0 should not occur
1770 smtp_setup_batch_msg(void)
1773 void *reset_point
= store_get(0);
1775 /* Save the line count at the start of each transaction - single commands
1776 like HELO and RSET count as whole transactions. */
1778 bsmtp_transaction_linecount
= receive_linecount
;
1780 if ((receive_feof
)()) return 0; /* Treat EOF as QUIT */
1782 smtp_reset(reset_point
); /* Reset for start of message */
1784 /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
1785 value. The values are 2 larger than the required yield of the function. */
1790 uschar
*recipient
= NULL
;
1791 int start
, end
, sender_domain
, recipient_domain
;
1793 switch(smtp_read_command(FALSE
))
1795 /* The HELO/EHLO commands set sender_address_helo if they have
1796 valid data; otherwise they are ignored, except that they do
1797 a reset of the state. */
1802 check_helo(smtp_cmd_data
);
1806 smtp_reset(reset_point
);
1807 bsmtp_transaction_linecount
= receive_linecount
;
1811 /* The MAIL FROM command requires an address as an operand. All we
1812 do here is to parse it for syntactic correctness. The form "<>" is
1813 a special case which converts into an empty string. The start/end
1814 pointers in the original are not used further for this address, as
1815 it is the canonical extracted address which is all that is kept. */
1818 smtp_mailcmd_count
++; /* Count for no-mail log */
1819 if (sender_address
!= NULL
)
1820 /* The function moan_smtp_batch() does not return. */
1821 moan_smtp_batch(smtp_cmd_buffer
, "503 Sender already given");
1823 if (smtp_cmd_data
[0] == 0)
1824 /* The function moan_smtp_batch() does not return. */
1825 moan_smtp_batch(smtp_cmd_buffer
, "501 MAIL FROM must have an address operand");
1827 /* Reset to start of message */
1829 smtp_reset(reset_point
);
1831 /* Apply SMTP rewrite */
1833 raw_sender
= ((rewrite_existflags
& rewrite_smtp
) != 0)?
1834 rewrite_one(smtp_cmd_data
, rewrite_smtp
|rewrite_smtp_sender
, NULL
, FALSE
,
1835 US
"", global_rewrite_rules
) : smtp_cmd_data
;
1837 /* Extract the address; the TRUE flag allows <> as valid */
1840 parse_extract_address(raw_sender
, &errmess
, &start
, &end
, &sender_domain
,
1843 if (raw_sender
== NULL
)
1844 /* The function moan_smtp_batch() does not return. */
1845 moan_smtp_batch(smtp_cmd_buffer
, "501 %s", errmess
);
1847 sender_address
= string_copy(raw_sender
);
1849 /* Qualify unqualified sender addresses if permitted to do so. */
1851 if (sender_domain
== 0 && sender_address
[0] != 0 && sender_address
[0] != '@')
1853 if (allow_unqualified_sender
)
1855 sender_address
= rewrite_address_qualify(sender_address
, FALSE
);
1856 DEBUG(D_receive
) debug_printf("unqualified address %s accepted "
1857 "and rewritten\n", raw_sender
);
1859 /* The function moan_smtp_batch() does not return. */
1860 else moan_smtp_batch(smtp_cmd_buffer
, "501 sender address must contain "
1866 /* The RCPT TO command requires an address as an operand. All we do
1867 here is to parse it for syntactic correctness. There may be any number
1868 of RCPT TO commands, specifying multiple senders. We build them all into
1869 a data structure that is in argc/argv format. The start/end values
1870 given by parse_extract_address are not used, as we keep only the
1871 extracted address. */
1874 if (sender_address
== NULL
)
1875 /* The function moan_smtp_batch() does not return. */
1876 moan_smtp_batch(smtp_cmd_buffer
, "503 No sender yet given");
1878 if (smtp_cmd_data
[0] == 0)
1879 /* The function moan_smtp_batch() does not return. */
1880 moan_smtp_batch(smtp_cmd_buffer
, "501 RCPT TO must have an address operand");
1882 /* Check maximum number allowed */
1884 if (recipients_max
> 0 && recipients_count
+ 1 > recipients_max
)
1885 /* The function moan_smtp_batch() does not return. */
1886 moan_smtp_batch(smtp_cmd_buffer
, "%s too many recipients",
1887 recipients_max_reject
? "552": "452");
1889 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
1890 recipient address */
1892 recipient
= rewrite_existflags
& rewrite_smtp
1893 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
1894 global_rewrite_rules
)
1897 recipient
= parse_extract_address(recipient
, &errmess
, &start
, &end
,
1898 &recipient_domain
, FALSE
);
1901 /* The function moan_smtp_batch() does not return. */
1902 moan_smtp_batch(smtp_cmd_buffer
, "501 %s", errmess
);
1904 /* If the recipient address is unqualified, qualify it if permitted. Then
1905 add it to the list of recipients. */
1907 if (recipient_domain
== 0)
1909 if (allow_unqualified_recipient
)
1911 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
1913 recipient
= rewrite_address_qualify(recipient
, TRUE
);
1915 /* The function moan_smtp_batch() does not return. */
1916 else moan_smtp_batch(smtp_cmd_buffer
, "501 recipient address must contain "
1919 receive_add_recipient(recipient
, -1);
1923 /* The DATA command is legal only if it follows successful MAIL FROM
1924 and RCPT TO commands. This function is complete when a valid DATA
1925 command is encountered. */
1928 if (sender_address
== NULL
|| recipients_count
<= 0)
1930 /* The function moan_smtp_batch() does not return. */
1931 if (sender_address
== NULL
)
1932 moan_smtp_batch(smtp_cmd_buffer
,
1933 "503 MAIL FROM:<sender> command must precede DATA");
1935 moan_smtp_batch(smtp_cmd_buffer
,
1936 "503 RCPT TO:<recipient> must precede DATA");
1940 done
= 3; /* DATA successfully achieved */
1941 message_ended
= END_NOTENDED
; /* Indicate in middle of message */
1946 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
1953 bsmtp_transaction_linecount
= receive_linecount
;
1964 /* The function moan_smtp_batch() does not return. */
1965 moan_smtp_batch(smtp_cmd_buffer
, "501 Unexpected argument data");
1970 /* The function moan_smtp_batch() does not return. */
1971 moan_smtp_batch(smtp_cmd_buffer
, "501 Unexpected NULL in SMTP command");
1976 /* The function moan_smtp_batch() does not return. */
1977 moan_smtp_batch(smtp_cmd_buffer
, "500 Command unrecognized");
1982 return done
- 2; /* Convert yield values */
1988 /*************************************************
1989 * Start an SMTP session *
1990 *************************************************/
1992 /* This function is called at the start of an SMTP session. Thereafter,
1993 smtp_setup_msg() is called to initiate each separate message. This
1994 function does host-specific testing, and outputs the banner line.
1997 Returns: FALSE if the session can not continue; something has
1998 gone wrong, or the connection to the host is blocked
2002 smtp_start_session(void)
2006 uschar
*user_msg
, *log_msg
;
2010 smtp_connection_start
= time(NULL
);
2011 for (smtp_ch_index
= 0; smtp_ch_index
< SMTP_HBUFF_SIZE
; smtp_ch_index
++)
2012 smtp_connection_had
[smtp_ch_index
] = SCH_NONE
;
2015 /* Default values for certain variables */
2017 helo_seen
= esmtp
= helo_accept_junk
= FALSE
;
2018 smtp_mailcmd_count
= 0;
2019 count_nonmail
= TRUE_UNSET
;
2020 synprot_error_count
= unknown_command_count
= nonmail_command_count
= 0;
2021 smtp_delay_mail
= smtp_rlm_base
;
2022 auth_advertised
= FALSE
;
2023 pipelining_advertised
= FALSE
;
2024 pipelining_enable
= TRUE
;
2025 sync_cmd_limit
= NON_SYNC_CMD_NON_PIPELINING
;
2026 smtp_exit_function_called
= FALSE
; /* For avoiding loop in not-quit exit */
2028 /* If receiving by -bs from a trusted user, or testing with -bh, we allow
2029 authentication settings from -oMaa to remain in force. */
2031 if (!host_checking
&& !sender_host_notsocket
) sender_host_authenticated
= NULL
;
2032 authenticated_by
= NULL
;
2035 tls_in
.cipher
= tls_in
.peerdn
= NULL
;
2036 tls_in
.ourcert
= tls_in
.peercert
= NULL
;
2038 tls_in
.ocsp
= OCSP_NOT_REQ
;
2039 tls_advertised
= FALSE
;
2041 dsn_advertised
= FALSE
;
2043 smtputf8_advertised
= FALSE
;
2046 /* Reset ACL connection variables */
2050 /* Allow for trailing 0 in the command and data buffers. */
2052 smtp_cmd_buffer
= (uschar
*)malloc(2*smtp_cmd_buffer_size
+ 2);
2053 if (smtp_cmd_buffer
== NULL
)
2054 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
,
2055 "malloc() failed for SMTP command buffer");
2056 smtp_cmd_buffer
[0] = 0;
2057 smtp_data_buffer
= smtp_cmd_buffer
+ smtp_cmd_buffer_size
+ 1;
2059 /* For batched input, the protocol setting can be overridden from the
2060 command line by a trusted caller. */
2062 if (smtp_batched_input
)
2064 if (received_protocol
== NULL
) received_protocol
= US
"local-bsmtp";
2067 /* For non-batched SMTP input, the protocol setting is forced here. It will be
2068 reset later if any of EHLO/AUTH/STARTTLS are received. */
2072 (sender_host_address
? protocols
: protocols_local
) [pnormal
];
2074 /* Set up the buffer for inputting using direct read() calls, and arrange to
2075 call the local functions instead of the standard C ones. */
2077 smtp_inbuffer
= (uschar
*)malloc(in_buffer_size
);
2078 if (smtp_inbuffer
== NULL
)
2079 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "malloc() failed for SMTP input buffer");
2080 receive_getc
= smtp_getc
;
2081 receive_get_cache
= smtp_get_cache
;
2082 receive_ungetc
= smtp_ungetc
;
2083 receive_feof
= smtp_feof
;
2084 receive_ferror
= smtp_ferror
;
2085 receive_smtp_buffered
= smtp_buffered
;
2086 smtp_inptr
= smtp_inend
= smtp_inbuffer
;
2087 smtp_had_eof
= smtp_had_error
= 0;
2089 /* Set up the message size limit; this may be host-specific */
2091 thismessage_size_limit
= expand_string_integer(message_size_limit
, TRUE
);
2092 if (expand_string_message
!= NULL
)
2094 if (thismessage_size_limit
== -1)
2095 log_write(0, LOG_MAIN
|LOG_PANIC
, "unable to expand message_size_limit: "
2096 "%s", expand_string_message
);
2098 log_write(0, LOG_MAIN
|LOG_PANIC
, "invalid message_size_limit: "
2099 "%s", expand_string_message
);
2100 smtp_closedown(US
"Temporary local problem - please try later");
2104 /* When a message is input locally via the -bs or -bS options, sender_host_
2105 unknown is set unless -oMa was used to force an IP address, in which case it
2106 is checked like a real remote connection. When -bs is used from inetd, this
2107 flag is not set, causing the sending host to be checked. The code that deals
2108 with IP source routing (if configured) is never required for -bs or -bS and
2109 the flag sender_host_notsocket is used to suppress it.
2111 If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
2112 reserve for certain hosts and/or networks. */
2114 if (!sender_host_unknown
)
2117 BOOL reserved_host
= FALSE
;
2119 /* Look up IP options (source routing info) on the socket if this is not an
2120 -oMa "host", and if any are found, log them and drop the connection.
2122 Linux (and others now, see below) is different to everyone else, so there
2123 has to be some conditional compilation here. Versions of Linux before 2.1.15
2124 used a structure whose name was "options". Somebody finally realized that
2125 this name was silly, and it got changed to "ip_options". I use the
2126 newer name here, but there is a fudge in the script that sets up os.h
2127 to define a macro in older Linux systems.
2129 Sigh. Linux is a fast-moving target. Another generation of Linux uses
2130 glibc 2, which has chosen ip_opts for the structure name. This is now
2131 really a glibc thing rather than a Linux thing, so the condition name
2132 has been changed to reflect this. It is relevant also to GNU/Hurd.
2134 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
2135 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
2136 a special macro defined in the os.h file.
2138 Some DGUX versions on older hardware appear not to support IP options at
2139 all, so there is now a general macro which can be set to cut out this
2142 How to do this properly in IPv6 is not yet known. */
2144 #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
2146 #ifdef GLIBC_IP_OPTIONS
2147 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
2152 #elif defined DARWIN_IP_OPTIONS
2158 if (!host_checking
&& !sender_host_notsocket
)
2161 EXIM_SOCKLEN_T optlen
= sizeof(struct ip_options
) + MAX_IPOPTLEN
;
2162 struct ip_options
*ipopt
= store_get(optlen
);
2164 struct ip_opts ipoptblock
;
2165 struct ip_opts
*ipopt
= &ipoptblock
;
2166 EXIM_SOCKLEN_T optlen
= sizeof(ipoptblock
);
2168 struct ipoption ipoptblock
;
2169 struct ipoption
*ipopt
= &ipoptblock
;
2170 EXIM_SOCKLEN_T optlen
= sizeof(ipoptblock
);
2173 /* Occasional genuine failures of getsockopt() have been seen - for
2174 example, "reset by peer". Therefore, just log and give up on this
2175 call, unless the error is ENOPROTOOPT. This error is given by systems
2176 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
2177 of writing. So for that error, carry on - we just can't do an IP options
2180 DEBUG(D_receive
) debug_printf("checking for IP options\n");
2182 if (getsockopt(fileno(smtp_out
), IPPROTO_IP
, IP_OPTIONS
, (uschar
*)(ipopt
),
2185 if (errno
!= ENOPROTOOPT
)
2187 log_write(0, LOG_MAIN
, "getsockopt() failed from %s: %s",
2188 host_and_ident(FALSE
), strerror(errno
));
2189 smtp_printf("451 SMTP service not available\r\n");
2194 /* Deal with any IP options that are set. On the systems I have looked at,
2195 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
2196 more logging data than will fit in big_buffer. Nevertheless, after somebody
2197 questioned this code, I've added in some paranoid checking. */
2199 else if (optlen
> 0)
2201 uschar
*p
= big_buffer
;
2202 uschar
*pend
= big_buffer
+ big_buffer_size
;
2203 uschar
*opt
, *adptr
;
2205 struct in_addr addr
;
2208 uschar
*optstart
= (uschar
*)(ipopt
->__data
);
2210 uschar
*optstart
= (uschar
*)(ipopt
->ip_opts
);
2212 uschar
*optstart
= (uschar
*)(ipopt
->ipopt_list
);
2215 DEBUG(D_receive
) debug_printf("IP options exist\n");
2217 Ustrcpy(p
, "IP options on incoming call:");
2220 for (opt
= optstart
; opt
!= NULL
&&
2221 opt
< (uschar
*)(ipopt
) + optlen
;)
2235 if (!string_format(p
, pend
-p
, " %s [@%s",
2236 (*opt
== IPOPT_SSRR
)? "SSRR" : "LSRR",
2238 inet_ntoa(*((struct in_addr
*)(&(ipopt
->faddr
))))))
2240 inet_ntoa(ipopt
->ip_dst
)))
2242 inet_ntoa(ipopt
->ipopt_dst
)))
2250 optcount
= (opt
[1] - 3) / sizeof(struct in_addr
);
2252 while (optcount
-- > 0)
2254 memcpy(&addr
, adptr
, sizeof(addr
));
2255 if (!string_format(p
, pend
- p
- 1, "%s%s",
2256 (optcount
== 0)? ":" : "@", inet_ntoa(addr
)))
2262 adptr
+= sizeof(struct in_addr
);
2271 if (pend
- p
< 4 + 3*opt
[1]) { opt
= NULL
; break; }
2274 for (i
= 0; i
< opt
[1]; i
++)
2276 sprintf(CS p
, "%2.2x ", opt
[i
]);
2287 log_write(0, LOG_MAIN
, "%s", big_buffer
);
2289 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2291 log_write(0, LOG_MAIN
|LOG_REJECT
,
2292 "connection from %s refused (IP options)", host_and_ident(FALSE
));
2294 smtp_printf("554 SMTP service not available\r\n");
2298 /* Length of options = 0 => there are no options */
2300 else DEBUG(D_receive
) debug_printf("no IP options found\n");
2302 #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
2304 /* Set keep-alive in socket options. The option is on by default. This
2305 setting is an attempt to get rid of some hanging connections that stick in
2306 read() when the remote end (usually a dialup) goes away. */
2308 if (smtp_accept_keepalive
&& !sender_host_notsocket
)
2309 ip_keepalive(fileno(smtp_out
), sender_host_address
, FALSE
);
2311 /* If the current host matches host_lookup, set the name by doing a
2312 reverse lookup. On failure, sender_host_name will be NULL and
2313 host_lookup_failed will be TRUE. This may or may not be serious - optional
2316 if (verify_check_host(&host_lookup
) == OK
)
2318 (void)host_name_lookup();
2319 host_build_sender_fullhost();
2322 /* Delay this until we have the full name, if it is looked up. */
2324 set_process_info("handling incoming connection from %s",
2325 host_and_ident(FALSE
));
2327 /* Expand smtp_receive_timeout, if needed */
2329 if (smtp_receive_timeout_s
)
2332 if ( !(exp
= expand_string(smtp_receive_timeout_s
))
2334 || (smtp_receive_timeout
= readconf_readtime(exp
, 0, FALSE
)) < 0
2336 log_write(0, LOG_MAIN
|LOG_PANIC
,
2337 "bad value for smtp_receive_timeout: '%s'", exp
? exp
: US
"");
2340 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2341 smtps port for use with older style SSL MTAs. */
2344 if (tls_in
.on_connect
&& tls_server_start(tls_require_ciphers
) != OK
)
2348 /* Test for explicit connection rejection */
2350 if (verify_check_host(&host_reject_connection
) == OK
)
2352 log_write(L_connection_reject
, LOG_MAIN
|LOG_REJECT
, "refused connection "
2353 "from %s (host_reject_connection)", host_and_ident(FALSE
));
2354 smtp_printf("554 SMTP service not available\r\n");
2358 /* Test with TCP Wrappers if so configured. There is a problem in that
2359 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2360 such as disks dying. In these cases, it is desirable to reject with a 4xx
2361 error instead of a 5xx error. There isn't a "right" way to detect such
2362 problems. The following kludge is used: errno is zeroed before calling
2363 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2364 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2367 #ifdef USE_TCP_WRAPPERS
2369 tcp_wrappers_name
= expand_string(tcp_wrappers_daemon_name
);
2370 if (tcp_wrappers_name
== NULL
)
2372 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "Expansion of \"%s\" "
2373 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name
),
2374 expand_string_message
);
2376 if (!hosts_ctl(tcp_wrappers_name
,
2377 (sender_host_name
== NULL
)? STRING_UNKNOWN
: CS sender_host_name
,
2378 (sender_host_address
== NULL
)? STRING_UNKNOWN
: CS sender_host_address
,
2379 (sender_ident
== NULL
)? STRING_UNKNOWN
: CS sender_ident
))
2381 if (errno
== 0 || errno
== ENOENT
)
2383 HDEBUG(D_receive
) debug_printf("tcp wrappers rejection\n");
2384 log_write(L_connection_reject
,
2385 LOG_MAIN
|LOG_REJECT
, "refused connection from %s "
2386 "(tcp wrappers)", host_and_ident(FALSE
));
2387 smtp_printf("554 SMTP service not available\r\n");
2391 int save_errno
= errno
;
2392 HDEBUG(D_receive
) debug_printf("tcp wrappers rejected with unexpected "
2393 "errno value %d\n", save_errno
);
2394 log_write(L_connection_reject
,
2395 LOG_MAIN
|LOG_REJECT
, "temporarily refused connection from %s "
2396 "(tcp wrappers errno=%d)", host_and_ident(FALSE
), save_errno
);
2397 smtp_printf("451 Temporary local problem - please try later\r\n");
2403 /* Check for reserved slots. The value of smtp_accept_count has already been
2404 incremented to include this process. */
2406 if (smtp_accept_max
> 0 &&
2407 smtp_accept_count
> smtp_accept_max
- smtp_accept_reserve
)
2409 if ((rc
= verify_check_host(&smtp_reserve_hosts
)) != OK
)
2411 log_write(L_connection_reject
,
2412 LOG_MAIN
, "temporarily refused connection from %s: not in "
2413 "reserve list: connected=%d max=%d reserve=%d%s",
2414 host_and_ident(FALSE
), smtp_accept_count
- 1, smtp_accept_max
,
2415 smtp_accept_reserve
, (rc
== DEFER
)? " (lookup deferred)" : "");
2416 smtp_printf("421 %s: Too many concurrent SMTP connections; "
2417 "please try again later\r\n", smtp_active_hostname
);
2420 reserved_host
= TRUE
;
2423 /* If a load level above which only messages from reserved hosts are
2424 accepted is set, check the load. For incoming calls via the daemon, the
2425 check is done in the superior process if there are no reserved hosts, to
2426 save a fork. In all cases, the load average will already be available
2427 in a global variable at this point. */
2429 if (smtp_load_reserve
>= 0 &&
2430 load_average
> smtp_load_reserve
&&
2432 verify_check_host(&smtp_reserve_hosts
) != OK
)
2434 log_write(L_connection_reject
,
2435 LOG_MAIN
, "temporarily refused connection from %s: not in "
2436 "reserve list and load average = %.2f", host_and_ident(FALSE
),
2437 (double)load_average
/1000.0);
2438 smtp_printf("421 %s: Too much load; please try again later\r\n",
2439 smtp_active_hostname
);
2443 /* Determine whether unqualified senders or recipients are permitted
2444 for this host. Unfortunately, we have to do this every time, in order to
2445 set the flags so that they can be inspected when considering qualifying
2446 addresses in the headers. For a site that permits no qualification, this
2447 won't take long, however. */
2449 allow_unqualified_sender
=
2450 verify_check_host(&sender_unqualified_hosts
) == OK
;
2452 allow_unqualified_recipient
=
2453 verify_check_host(&recipient_unqualified_hosts
) == OK
;
2455 /* Determine whether HELO/EHLO is required for this host. The requirement
2456 can be hard or soft. */
2458 helo_required
= verify_check_host(&helo_verify_hosts
) == OK
;
2460 helo_verify
= verify_check_host(&helo_try_verify_hosts
) == OK
;
2462 /* Determine whether this hosts is permitted to send syntactic junk
2463 after a HELO or EHLO command. */
2465 helo_accept_junk
= verify_check_host(&helo_accept_junk_hosts
) == OK
;
2468 /* For batch SMTP input we are now done. */
2470 if (smtp_batched_input
) return TRUE
;
2472 #ifdef SUPPORT_PROXY
2473 /* If valid Proxy Protocol source is connecting, set up session.
2474 * Failure will not allow any SMTP function other than QUIT. */
2475 proxy_session
= FALSE
;
2476 proxy_session_failed
= FALSE
;
2477 if (check_proxy_protocol_host())
2479 if (setup_proxy_protocol_host() == FALSE
)
2481 proxy_session_failed
= TRUE
;
2483 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
2487 sender_host_name
= NULL
;
2488 (void)host_name_lookup();
2489 host_build_sender_fullhost();
2494 /* Run the ACL if it exists */
2497 if (acl_smtp_connect
!= NULL
)
2500 rc
= acl_check(ACL_WHERE_CONNECT
, NULL
, acl_smtp_connect
, &user_msg
,
2504 (void)smtp_handle_acl_fail(ACL_WHERE_CONNECT
, rc
, user_msg
, log_msg
);
2509 /* Output the initial message for a two-way SMTP connection. It may contain
2510 newlines, which then cause a multi-line response to be given. */
2512 code
= US
"220"; /* Default status code */
2513 esc
= US
""; /* Default extended status code */
2514 esclen
= 0; /* Length of esc */
2518 if (!(s
= expand_string(smtp_banner
)))
2519 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "Expansion of \"%s\" (smtp_banner) "
2520 "failed: %s", smtp_banner
, expand_string_message
);
2526 smtp_message_code(&code
, &codelen
, &s
, NULL
, TRUE
);
2530 esclen
= codelen
- 4;
2534 /* Remove any terminating newlines; might as well remove trailing space too */
2537 while (p
> s
&& isspace(p
[-1])) p
--;
2540 /* It seems that CC:Mail is braindead, and assumes that the greeting message
2541 is all contained in a single IP packet. The original code wrote out the
2542 greeting using several calls to fprint/fputc, and on busy servers this could
2543 cause it to be split over more than one packet - which caused CC:Mail to fall
2544 over when it got the second part of the greeting after sending its first
2545 command. Sigh. To try to avoid this, build the complete greeting message
2546 first, and output it in one fell swoop. This gives a better chance of it
2547 ending up as a single packet. */
2549 ss
= store_get(size
);
2553 do /* At least once, in case we have an empty string */
2556 uschar
*linebreak
= Ustrchr(p
, '\n');
2557 ss
= string_catn(ss
, &size
, &ptr
, code
, 3);
2558 if (linebreak
== NULL
)
2561 ss
= string_catn(ss
, &size
, &ptr
, US
" ", 1);
2565 len
= linebreak
- p
;
2566 ss
= string_catn(ss
, &size
, &ptr
, US
"-", 1);
2568 ss
= string_catn(ss
, &size
, &ptr
, esc
, esclen
);
2569 ss
= string_catn(ss
, &size
, &ptr
, p
, len
);
2570 ss
= string_catn(ss
, &size
, &ptr
, US
"\r\n", 2);
2572 if (linebreak
!= NULL
) p
++;
2576 ss
[ptr
] = 0; /* string_cat leaves room for this */
2578 /* Before we write the banner, check that there is no input pending, unless
2579 this synchronisation check is disabled. */
2583 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP protocol "
2584 "synchronization error (input sent without waiting for greeting): "
2585 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE
),
2586 string_printing(smtp_inptr
));
2587 smtp_printf("554 SMTP synchronization error\r\n");
2591 /* Now output the banner */
2593 smtp_printf("%s", ss
);
2601 /*************************************************
2602 * Handle SMTP syntax and protocol errors *
2603 *************************************************/
2605 /* Write to the log for SMTP syntax errors in incoming commands, if configured
2606 to do so. Then transmit the error response. The return value depends on the
2607 number of syntax and protocol errors in this SMTP session.
2610 type error type, given as a log flag bit
2611 code response code; <= 0 means don't send a response
2612 data data to reflect in the response (can be NULL)
2613 errmess the error message
2615 Returns: -1 limit of syntax/protocol errors NOT exceeded
2616 +1 limit of syntax/protocol errors IS exceeded
2618 These values fit in with the values of the "done" variable in the main
2619 processing loop in smtp_setup_msg(). */
2622 synprot_error(int type
, int code
, uschar
*data
, uschar
*errmess
)
2626 log_write(type
, LOG_MAIN
, "SMTP %s error in \"%s\" %s %s",
2627 (type
== L_smtp_syntax_error
)? "syntax" : "protocol",
2628 string_printing(smtp_cmd_buffer
), host_and_ident(TRUE
), errmess
);
2630 if (++synprot_error_count
> smtp_max_synprot_errors
)
2633 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
2634 "syntax or protocol errors (last command was \"%s\")",
2635 host_and_ident(FALSE
), string_printing(smtp_cmd_buffer
));
2640 smtp_printf("%d%c%s%s%s\r\n", code
, (yield
== 1)? '-' : ' ',
2641 (data
== NULL
)? US
"" : data
, (data
== NULL
)? US
"" : US
": ", errmess
);
2643 smtp_printf("%d Too many syntax or protocol errors\r\n", code
);
2652 /*************************************************
2653 * Log incomplete transactions *
2654 *************************************************/
2656 /* This function is called after a transaction has been aborted by RSET, QUIT,
2657 connection drops or other errors. It logs the envelope information received
2658 so far in order to preserve address verification attempts.
2660 Argument: string to indicate what aborted the transaction
2665 incomplete_transaction_log(uschar
*what
)
2667 if (sender_address
== NULL
|| /* No transaction in progress */
2668 !LOGGING(smtp_incomplete_transaction
))
2671 /* Build list of recipients for logging */
2673 if (recipients_count
> 0)
2676 raw_recipients
= store_get(recipients_count
* sizeof(uschar
*));
2677 for (i
= 0; i
< recipients_count
; i
++)
2678 raw_recipients
[i
] = recipients_list
[i
].address
;
2679 raw_recipients_count
= recipients_count
;
2682 log_write(L_smtp_incomplete_transaction
, LOG_MAIN
|LOG_SENDER
|LOG_RECIPIENTS
,
2683 "%s incomplete transaction (%s)", host_and_ident(TRUE
), what
);
2689 /*************************************************
2690 * Send SMTP response, possibly multiline *
2691 *************************************************/
2693 /* There are, it seems, broken clients out there that cannot handle multiline
2694 responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
2695 output nothing for non-final calls, and only the first line for anything else.
2698 code SMTP code, may involve extended status codes
2699 codelen length of smtp code; if > 4 there's an ESC
2700 final FALSE if the last line isn't the final line
2701 msg message text, possibly containing newlines
2707 smtp_respond(uschar
* code
, int codelen
, BOOL final
, uschar
*msg
)
2712 if (!final
&& no_multiline_responses
) return;
2717 esclen
= codelen
- 4;
2720 /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
2721 have had the same. Note: this code is also present in smtp_printf(). It would
2722 be tidier to have it only in one place, but when it was added, it was easier to
2723 do it that way, so as not to have to mess with the code for the RCPT command,
2724 which sometimes uses smtp_printf() and sometimes smtp_respond(). */
2726 if (rcpt_in_progress
)
2728 if (rcpt_smtp_response
== NULL
)
2729 rcpt_smtp_response
= string_copy(msg
);
2730 else if (rcpt_smtp_response_same
&&
2731 Ustrcmp(rcpt_smtp_response
, msg
) != 0)
2732 rcpt_smtp_response_same
= FALSE
;
2733 rcpt_in_progress
= FALSE
;
2736 /* Not output the message, splitting it up into multiple lines if necessary. */
2740 uschar
*nl
= Ustrchr(msg
, '\n');
2743 smtp_printf("%.3s%c%.*s%s\r\n", code
, final
? ' ':'-', esclen
, esc
, msg
);
2746 else if (nl
[1] == 0 || no_multiline_responses
)
2748 smtp_printf("%.3s%c%.*s%.*s\r\n", code
, final
? ' ':'-', esclen
, esc
,
2749 (int)(nl
- msg
), msg
);
2754 smtp_printf("%.3s-%.*s%.*s\r\n", code
, esclen
, esc
, (int)(nl
- msg
), msg
);
2756 while (isspace(*msg
)) msg
++;
2764 /*************************************************
2765 * Parse user SMTP message *
2766 *************************************************/
2768 /* This function allows for user messages overriding the response code details
2769 by providing a suitable response code string at the start of the message
2770 user_msg. Check the message for starting with a response code and optionally an
2771 extended status code. If found, check that the first digit is valid, and if so,
2772 change the code pointer and length to use the replacement. An invalid code
2773 causes a panic log; in this case, if the log messages is the same as the user
2774 message, we must also adjust the value of the log message to show the code that
2775 is actually going to be used (the original one).
2777 This function is global because it is called from receive.c as well as within
2780 Note that the code length returned includes the terminating whitespace
2781 character, which is always included in the regex match.
2784 code SMTP code, may involve extended status codes
2785 codelen length of smtp code; if > 4 there's an ESC
2787 log_msg optional log message, to be adjusted with the new SMTP code
2788 check_valid if true, verify the response code
2794 smtp_message_code(uschar
**code
, int *codelen
, uschar
**msg
, uschar
**log_msg
,
2800 if (!msg
|| !*msg
) return;
2802 if ((n
= pcre_exec(regex_smtp_code
, NULL
, CS
*msg
, Ustrlen(*msg
), 0,
2803 PCRE_EOPT
, ovector
, sizeof(ovector
)/sizeof(int))) < 0) return;
2805 if (check_valid
&& (*msg
)[0] != (*code
)[0])
2807 log_write(0, LOG_MAIN
|LOG_PANIC
, "configured error code starts with "
2808 "incorrect digit (expected %c) in \"%s\"", (*code
)[0], *msg
);
2809 if (log_msg
!= NULL
&& *log_msg
== *msg
)
2810 *log_msg
= string_sprintf("%s %s", *code
, *log_msg
+ ovector
[1]);
2815 *codelen
= ovector
[1]; /* Includes final space */
2817 *msg
+= ovector
[1]; /* Chop the code off the message */
2824 /*************************************************
2825 * Handle an ACL failure *
2826 *************************************************/
2828 /* This function is called when acl_check() fails. As well as calls from within
2829 this module, it is called from receive.c for an ACL after DATA. It sorts out
2830 logging the incident, and sets up the error response. A message containing
2831 newlines is turned into a multiline SMTP response, but for logging, only the
2834 There's a table of default permanent failure response codes to use in
2835 globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
2836 defaults disabled in Exim. However, discussion in connection with RFC 821bis
2837 (aka RFC 2821) has concluded that the response should be 252 in the disabled
2838 state, because there are broken clients that try VRFY before RCPT. A 5xx
2839 response should be given only when the address is positively known to be
2840 undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
2841 no explicit code, but if there is one we let it know best.
2842 Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
2844 From Exim 4.63, it is possible to override the response code details by
2845 providing a suitable response code string at the start of the message provided
2846 in user_msg. The code's first digit is checked for validity.
2849 where where the ACL was called from
2851 user_msg a message that can be included in an SMTP response
2852 log_msg a message for logging
2854 Returns: 0 in most cases
2855 2 if the failure code was FAIL_DROP, in which case the
2856 SMTP connection should be dropped (this value fits with the
2857 "done" variable in smtp_setup_msg() below)
2861 smtp_handle_acl_fail(int where
, int rc
, uschar
*user_msg
, uschar
*log_msg
)
2863 BOOL drop
= rc
== FAIL_DROP
;
2867 uschar
*sender_info
= US
"";
2869 #ifdef WITH_CONTENT_SCAN
2870 (where
== ACL_WHERE_MIME
)? US
"during MIME ACL checks" :
2872 (where
== ACL_WHERE_PREDATA
)? US
"DATA" :
2873 (where
== ACL_WHERE_DATA
)? US
"after DATA" :
2874 #ifndef DISABLE_PRDR
2875 (where
== ACL_WHERE_PRDR
)? US
"after DATA PRDR" :
2877 (smtp_cmd_data
== NULL
)?
2878 string_sprintf("%s in \"connect\" ACL", acl_wherenames
[where
]) :
2879 string_sprintf("%s %s", acl_wherenames
[where
], smtp_cmd_data
);
2881 if (drop
) rc
= FAIL
;
2883 /* Set the default SMTP code, and allow a user message to change it. */
2885 smtp_code
= rc
== FAIL
? acl_wherecodes
[where
] : US
"451";
2886 smtp_message_code(&smtp_code
, &codelen
, &user_msg
, &log_msg
,
2887 where
!= ACL_WHERE_VRFY
);
2889 /* We used to have sender_address here; however, there was a bug that was not
2890 updating sender_address after a rewrite during a verify. When this bug was
2891 fixed, sender_address at this point became the rewritten address. I'm not sure
2892 this is what should be logged, so I've changed to logging the unrewritten
2893 address to retain backward compatibility. */
2895 #ifndef WITH_CONTENT_SCAN
2896 if (where
== ACL_WHERE_RCPT
|| where
== ACL_WHERE_DATA
)
2898 if (where
== ACL_WHERE_RCPT
|| where
== ACL_WHERE_DATA
|| where
== ACL_WHERE_MIME
)
2901 sender_info
= string_sprintf("F=<%s>%s%s%s%s ",
2902 sender_address_unrewritten
? sender_address_unrewritten
: sender_address
,
2903 sender_host_authenticated
? US
" A=" : US
"",
2904 sender_host_authenticated
? sender_host_authenticated
: US
"",
2905 sender_host_authenticated
&& authenticated_id
? US
":" : US
"",
2906 sender_host_authenticated
&& authenticated_id
? authenticated_id
: US
""
2910 /* If there's been a sender verification failure with a specific message, and
2911 we have not sent a response about it yet, do so now, as a preliminary line for
2912 failures, but not defers. However, always log it for defer, and log it for fail
2913 unless the sender_verify_fail log selector has been turned off. */
2915 if (sender_verified_failed
!= NULL
&&
2916 !testflag(sender_verified_failed
, af_sverify_told
))
2918 BOOL save_rcpt_in_progress
= rcpt_in_progress
;
2919 rcpt_in_progress
= FALSE
; /* So as not to treat these as the error */
2921 setflag(sender_verified_failed
, af_sverify_told
);
2923 if (rc
!= FAIL
|| LOGGING(sender_verify_fail
))
2924 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s sender verify %s for <%s>%s",
2925 host_and_ident(TRUE
),
2926 ((sender_verified_failed
->special_action
& 255) == DEFER
)? "defer":"fail",
2927 sender_verified_failed
->address
,
2928 (sender_verified_failed
->message
== NULL
)? US
"" :
2929 string_sprintf(": %s", sender_verified_failed
->message
));
2931 if (rc
== FAIL
&& sender_verified_failed
->user_message
!= NULL
)
2932 smtp_respond(smtp_code
, codelen
, FALSE
, string_sprintf(
2933 testflag(sender_verified_failed
, af_verify_pmfail
)?
2934 "Postmaster verification failed while checking <%s>\n%s\n"
2935 "Several RFCs state that you are required to have a postmaster\n"
2936 "mailbox for each mail domain. This host does not accept mail\n"
2937 "from domains whose servers reject the postmaster address."
2939 testflag(sender_verified_failed
, af_verify_nsfail
)?
2940 "Callback setup failed while verifying <%s>\n%s\n"
2941 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
2942 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
2943 "RFC requirements, and stops you from receiving standard bounce\n"
2944 "messages. This host does not accept mail from domains whose servers\n"
2947 "Verification failed for <%s>\n%s",
2948 sender_verified_failed
->address
,
2949 sender_verified_failed
->user_message
));
2951 rcpt_in_progress
= save_rcpt_in_progress
;
2954 /* Sort out text for logging */
2956 log_msg
= (log_msg
== NULL
)? US
"" : string_sprintf(": %s", log_msg
);
2957 lognl
= Ustrchr(log_msg
, '\n');
2958 if (lognl
!= NULL
) *lognl
= 0;
2960 /* Send permanent failure response to the command, but the code used isn't
2961 always a 5xx one - see comments at the start of this function. If the original
2962 rc was FAIL_DROP we drop the connection and yield 2. */
2964 if (rc
== FAIL
) smtp_respond(smtp_code
, codelen
, TRUE
, (user_msg
== NULL
)?
2965 US
"Administrative prohibition" : user_msg
);
2967 /* Send temporary failure response to the command. Don't give any details,
2968 unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
2969 verb, and for a header verify when smtp_return_error_details is set.
2971 This conditional logic is all somewhat of a mess because of the odd
2972 interactions between temp_details and return_error_details. One day it should
2973 be re-implemented in a tidier fashion. */
2977 if (acl_temp_details
&& user_msg
!= NULL
)
2979 if (smtp_return_error_details
&&
2980 sender_verified_failed
!= NULL
&&
2981 sender_verified_failed
->message
!= NULL
)
2983 smtp_respond(smtp_code
, codelen
, FALSE
, sender_verified_failed
->message
);
2985 smtp_respond(smtp_code
, codelen
, TRUE
, user_msg
);
2988 smtp_respond(smtp_code
, codelen
, TRUE
,
2989 US
"Temporary local problem - please try later");
2992 /* Log the incident to the logs that are specified by log_reject_target
2993 (default main, reject). This can be empty to suppress logging of rejections. If
2994 the connection is not forcibly to be dropped, return 0. Otherwise, log why it
2995 is closing if required and return 2. */
2997 if (log_reject_target
!= 0)
3000 uschar
* tls
= s_tlslog(NULL
, NULL
, NULL
);
3001 if (!tls
) tls
= US
"";
3003 uschar
* tls
= US
"";
3005 log_write(0, log_reject_target
, "%s%s%s %s%srejected %s%s",
3006 LOGGING(dnssec
) && sender_host_dnssec
? US
" DS" : US
"",
3007 host_and_ident(TRUE
),
3010 rc
== FAIL
? US
"" : US
"temporarily ",
3014 if (!drop
) return 0;
3016 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by DROP in ACL",
3017 smtp_get_connection_info());
3019 /* Run the not-quit ACL, but without any custom messages. This should not be a
3020 problem, because we get here only if some other ACL has issued "drop", and
3021 in that case, *its* custom messages will have been used above. */
3023 smtp_notquit_exit(US
"acl-drop", NULL
, NULL
);
3030 /*************************************************
3031 * Handle SMTP exit when QUIT is not given *
3032 *************************************************/
3034 /* This function provides a logging/statistics hook for when an SMTP connection
3035 is dropped on the floor or the other end goes away. It's a global function
3036 because it's called from receive.c as well as this module. As well as running
3037 the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
3038 response, either with a custom message from the ACL, or using a default. There
3039 is one case, however, when no message is output - after "drop". In that case,
3040 the ACL that obeyed "drop" has already supplied the custom message, and NULL is
3041 passed to this function.
3043 In case things go wrong while processing this function, causing an error that
3044 may re-enter this funtion, there is a recursion check.
3047 reason What $smtp_notquit_reason will be set to in the ACL;
3048 if NULL, the ACL is not run
3049 code The error code to return as part of the response
3050 defaultrespond The default message if there's no user_msg
3056 smtp_notquit_exit(uschar
*reason
, uschar
*code
, uschar
*defaultrespond
, ...)
3059 uschar
*user_msg
= NULL
;
3060 uschar
*log_msg
= NULL
;
3062 /* Check for recursive acll */
3064 if (smtp_exit_function_called
)
3066 log_write(0, LOG_PANIC
, "smtp_notquit_exit() called more than once (%s)",
3070 smtp_exit_function_called
= TRUE
;
3072 /* Call the not-QUIT ACL, if there is one, unless no reason is given. */
3074 if (acl_smtp_notquit
&& reason
)
3076 smtp_notquit_reason
= reason
;
3077 if ((rc
= acl_check(ACL_WHERE_NOTQUIT
, NULL
, acl_smtp_notquit
, &user_msg
,
3078 &log_msg
)) == ERROR
)
3079 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for not-QUIT returned ERROR: %s",
3083 /* Write an SMTP response if we are expected to give one. As the default
3084 responses are all internal, they should always fit in the buffer, but code a
3085 warning, just in case. Note that string_vformat() still leaves a complete
3086 string, even if it is incomplete. */
3088 if (code
&& defaultrespond
)
3091 smtp_respond(code
, 3, TRUE
, user_msg
);
3096 va_start(ap
, defaultrespond
);
3097 if (!string_vformat(buffer
, sizeof(buffer
), CS defaultrespond
, ap
))
3098 log_write(0, LOG_MAIN
|LOG_PANIC
, "string too large in smtp_notquit_exit()");
3099 smtp_printf("%s %s\r\n", code
, buffer
);
3109 /*************************************************
3110 * Verify HELO argument *
3111 *************************************************/
3113 /* This function is called if helo_verify_hosts or helo_try_verify_hosts is
3114 matched. It is also called from ACL processing if verify = helo is used and
3115 verification was not previously tried (i.e. helo_try_verify_hosts was not
3116 matched). The result of its processing is to set helo_verified and
3117 helo_verify_failed. These variables should both be FALSE for this function to
3120 Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow
3121 for IPv6 ::ffff: literals.
3124 Returns: TRUE if testing was completed;
3125 FALSE on a temporary failure
3129 smtp_verify_helo(void)
3133 HDEBUG(D_receive
) debug_printf("verifying EHLO/HELO argument \"%s\"\n",
3136 if (sender_helo_name
== NULL
)
3138 HDEBUG(D_receive
) debug_printf("no EHLO/HELO command was issued\n");
3141 /* Deal with the case of -bs without an IP address */
3143 else if (sender_host_address
== NULL
)
3145 HDEBUG(D_receive
) debug_printf("no client IP address: assume success\n");
3146 helo_verified
= TRUE
;
3149 /* Deal with the more common case when there is a sending IP address */
3151 else if (sender_helo_name
[0] == '[')
3153 helo_verified
= Ustrncmp(sender_helo_name
+1, sender_host_address
,
3154 Ustrlen(sender_host_address
)) == 0;
3159 if (strncmpic(sender_host_address
, US
"::ffff:", 7) == 0)
3160 helo_verified
= Ustrncmp(sender_helo_name
+ 1,
3161 sender_host_address
+ 7, Ustrlen(sender_host_address
) - 7) == 0;
3166 { if (helo_verified
) debug_printf("matched host address\n"); }
3169 /* Do a reverse lookup if one hasn't already given a positive or negative
3170 response. If that fails, or the name doesn't match, try checking with a forward
3175 if (sender_host_name
== NULL
&& !host_lookup_failed
)
3176 yield
= host_name_lookup() != DEFER
;
3178 /* If a host name is known, check it and all its aliases. */
3180 if (sender_host_name
)
3181 if ((helo_verified
= strcmpic(sender_host_name
, sender_helo_name
) == 0))
3183 sender_helo_dnssec
= sender_host_dnssec
;
3184 HDEBUG(D_receive
) debug_printf("matched host name\n");
3188 uschar
**aliases
= sender_host_aliases
;
3190 if ((helo_verified
= strcmpic(*aliases
++, sender_helo_name
) == 0))
3192 sender_helo_dnssec
= sender_host_dnssec
;
3196 HDEBUG(D_receive
) if (helo_verified
)
3197 debug_printf("matched alias %s\n", *(--aliases
));
3200 /* Final attempt: try a forward lookup of the helo name */
3209 h
.name
= sender_helo_name
;
3216 HDEBUG(D_receive
) debug_printf("getting IP address for %s\n",
3218 rc
= host_find_bydns(&h
, NULL
, HOST_FIND_BY_A
,
3219 NULL
, NULL
, NULL
, &d
, NULL
, NULL
);
3220 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
3221 for (hh
= &h
; hh
; hh
= hh
->next
)
3222 if (Ustrcmp(hh
->address
, sender_host_address
) == 0)
3224 helo_verified
= TRUE
;
3225 if (h
.dnssec
== DS_YES
) sender_helo_dnssec
= TRUE
;
3228 debug_printf("IP address for %s matches calling address\n"
3229 "Forward DNS security status: %sverified\n",
3230 sender_helo_name
, sender_helo_dnssec
? "" : "un");
3237 if (!helo_verified
) helo_verify_failed
= TRUE
; /* We've tried ... */
3244 /*************************************************
3245 * Send user response message *
3246 *************************************************/
3248 /* This function is passed a default response code and a user message. It calls
3249 smtp_message_code() to check and possibly modify the response code, and then
3250 calls smtp_respond() to transmit the response. I put this into a function
3251 just to avoid a lot of repetition.
3254 code the response code
3255 user_msg the user message
3261 smtp_user_msg(uschar
*code
, uschar
*user_msg
)
3264 smtp_message_code(&code
, &len
, &user_msg
, NULL
, TRUE
);
3265 smtp_respond(code
, len
, TRUE
, user_msg
);
3271 smtp_in_auth(auth_instance
*au
, uschar
** s
, uschar
** ss
)
3273 const uschar
*set_id
= NULL
;
3276 /* Run the checking code, passing the remainder of the command line as
3277 data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
3278 it as the only set numerical variable. The authenticator may set $auth<n>
3279 and also set other numeric variables. The $auth<n> variables are preferred
3280 nowadays; the numerical variables remain for backwards compatibility.
3282 Afterwards, have a go at expanding the set_id string, even if
3283 authentication failed - for bad passwords it can be useful to log the
3284 userid. On success, require set_id to expand and exist, and put it in
3285 authenticated_id. Save this in permanent store, as the working store gets
3286 reset at HELO, RSET, etc. */
3288 for (i
= 0; i
< AUTH_VARS
; i
++) auth_vars
[i
] = NULL
;
3290 expand_nlength
[0] = 0; /* $0 contains nothing */
3292 rc
= (au
->info
->servercode
)(au
, smtp_cmd_data
);
3293 if (au
->set_id
) set_id
= expand_string(au
->set_id
);
3294 expand_nmax
= -1; /* Reset numeric variables */
3295 for (i
= 0; i
< AUTH_VARS
; i
++) auth_vars
[i
] = NULL
; /* Reset $auth<n> */
3297 /* The value of authenticated_id is stored in the spool file and printed in
3298 log lines. It must not contain binary zeros or newline characters. In
3299 normal use, it never will, but when playing around or testing, this error
3300 can (did) happen. To guard against this, ensure that the id contains only
3301 printing characters. */
3303 if (set_id
) set_id
= string_printing(set_id
);
3305 /* For the non-OK cases, set up additional logging data if set_id
3309 set_id
= set_id
&& *set_id
3310 ? string_sprintf(" (set_id=%s)", set_id
) : US
"";
3312 /* Switch on the result */
3317 if (!au
->set_id
|| set_id
) /* Complete success */
3319 if (set_id
) authenticated_id
= string_copy_malloc(set_id
);
3320 sender_host_authenticated
= au
->name
;
3321 authentication_failed
= FALSE
;
3322 authenticated_fail_id
= NULL
; /* Impossible to already be set? */
3325 (sender_host_address
? protocols
: protocols_local
)
3326 [pextend
+ pauthed
+ (tls_in
.active
>= 0 ? pcrpted
:0)];
3327 *s
= *ss
= US
"235 Authentication succeeded";
3328 authenticated_by
= au
;
3332 /* Authentication succeeded, but we failed to expand the set_id string.
3333 Treat this as a temporary error. */
3335 auth_defer_msg
= expand_string_message
;
3339 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3340 *s
= string_sprintf("435 Unable to authenticate at present%s",
3341 auth_defer_user_msg
);
3342 *ss
= string_sprintf("435 Unable to authenticate at present%s: %s",
3343 set_id
, auth_defer_msg
);
3347 *s
= *ss
= US
"501 Invalid base64 data";
3351 *s
= *ss
= US
"501 Authentication cancelled";
3355 *s
= *ss
= US
"553 Initial data not expected";
3359 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3360 *s
= US
"535 Incorrect authentication data";
3361 *ss
= string_sprintf("535 Incorrect authentication data%s", set_id
);
3365 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3366 *s
= US
"435 Internal error";
3367 *ss
= string_sprintf("435 Internal error%s: return %d from authentication "
3368 "check", set_id
, rc
);
3380 qualify_recipient(uschar
** recipient
, uschar
* smtp_cmd_data
, uschar
* tag
)
3383 if (allow_unqualified_recipient
|| strcmpic(*recipient
, US
"postmaster") == 0)
3385 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
3387 rd
= Ustrlen(recipient
) + 1;
3388 *recipient
= rewrite_address_qualify(*recipient
, TRUE
);
3391 smtp_printf("501 %s: recipient address must contain a domain\r\n",
3393 log_write(L_smtp_syntax_error
,
3394 LOG_MAIN
|LOG_REJECT
, "unqualified %s rejected: <%s> %s%s",
3395 tag
, *recipient
, host_and_ident(TRUE
), host_lookup_msg
);
3403 smtp_quit_handler(uschar
** user_msgp
, uschar
** log_msgp
)
3406 incomplete_transaction_log(US
"QUIT");
3407 if (acl_smtp_quit
!= NULL
)
3409 int rc
= acl_check(ACL_WHERE_QUIT
, NULL
, acl_smtp_quit
, user_msgp
, log_msgp
);
3411 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for QUIT returned ERROR: %s",
3415 smtp_respond(US
"221", 3, TRUE
, *user_msgp
);
3417 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
3420 tls_close(TRUE
, TRUE
);
3423 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by QUIT",
3424 smtp_get_connection_info());
3429 smtp_rset_handler(void)
3432 incomplete_transaction_log(US
"RSET");
3433 smtp_printf("250 Reset OK\r\n");
3434 cmd_list
[CMD_LIST_RSET
].is_mail_cmd
= FALSE
;
3439 /*************************************************
3440 * Initialize for SMTP incoming message *
3441 *************************************************/
3443 /* This function conducts the initial dialogue at the start of an incoming SMTP
3444 message, and builds a list of recipients. However, if the incoming message
3445 is part of a batch (-bS option) a separate function is called since it would
3446 be messy having tests splattered about all over this function. This function
3447 therefore handles the case where interaction is occurring. The input and output
3448 files are set up in smtp_in and smtp_out.
3450 The global recipients_list is set to point to a vector of recipient_item
3451 blocks, whose number is given by recipients_count. This is extended by the
3452 receive_add_recipient() function. The global variable sender_address is set to
3453 the sender's address. The yield is +1 if a message has been successfully
3454 started, 0 if a QUIT command was encountered or the connection was refused from
3455 the particular host, or -1 if the connection was lost.
3459 Returns: > 0 message successfully started (reached DATA)
3460 = 0 QUIT read or end of file reached or call refused
3465 smtp_setup_msg(void)
3468 BOOL toomany
= FALSE
;
3469 BOOL discarded
= FALSE
;
3470 BOOL last_was_rej_mail
= FALSE
;
3471 BOOL last_was_rcpt
= FALSE
;
3472 void *reset_point
= store_get(0);
3474 DEBUG(D_receive
) debug_printf("smtp_setup_msg entered\n");
3476 /* Reset for start of new message. We allow one RSET not to be counted as a
3477 nonmail command, for those MTAs that insist on sending it between every
3478 message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of
3479 TLS between messages (an Exim client may do this if it has messages queued up
3480 for the host). Note: we do NOT reset AUTH at this point. */
3482 smtp_reset(reset_point
);
3483 message_ended
= END_NOTSTARTED
;
3485 chunking_state
= chunking_offered
? CHUNKING_OFFERED
: CHUNKING_NOT_OFFERED
;
3487 cmd_list
[CMD_LIST_RSET
].is_mail_cmd
= TRUE
;
3488 cmd_list
[CMD_LIST_HELO
].is_mail_cmd
= TRUE
;
3489 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= TRUE
;
3491 cmd_list
[CMD_LIST_STARTTLS
].is_mail_cmd
= TRUE
;
3492 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= TRUE
;
3495 /* Set the local signal handler for SIGTERM - it tries to end off tidily */
3497 os_non_restarting_signal(SIGTERM
, command_sigterm_handler
);
3499 /* Batched SMTP is handled in a different function. */
3501 if (smtp_batched_input
) return smtp_setup_batch_msg();
3503 /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
3504 value. The values are 2 larger than the required yield of the function. */
3508 const uschar
**argv
;
3509 uschar
*etrn_command
;
3510 uschar
*etrn_serialize_key
;
3512 uschar
*log_msg
, *smtp_code
;
3513 uschar
*user_msg
= NULL
;
3514 uschar
*recipient
= NULL
;
3515 uschar
*hello
= NULL
;
3517 BOOL was_rej_mail
= FALSE
;
3518 BOOL was_rcpt
= FALSE
;
3519 void (*oldsignal
)(int);
3521 int start
, end
, sender_domain
, recipient_domain
;
3525 uschar
*orcpt
= NULL
;
3528 #if defined(SUPPORT_TLS) && defined(AUTH_TLS)
3529 /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */
3530 if ( tls_in
.active
>= 0
3532 && tls_in
.certificate_verified
3533 && cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
3536 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= FALSE
;
3538 && (rc
= acl_check(ACL_WHERE_AUTH
, NULL
, acl_smtp_auth
,
3539 &user_msg
, &log_msg
)) != OK
3542 done
= smtp_handle_acl_fail(ACL_WHERE_AUTH
, rc
, user_msg
, log_msg
);
3546 for (au
= auths
; au
; au
= au
->next
)
3547 if (strcmpic(US
"tls", au
->driver_name
) == 0)
3549 smtp_cmd_data
= NULL
;
3551 if (smtp_in_auth(au
, &s
, &ss
) == OK
)
3552 { DEBUG(D_auth
) debug_printf("tls auth succeeded\n"); }
3554 { DEBUG(D_auth
) debug_printf("tls auth not succeeded\n"); }
3560 switch(smtp_read_command(TRUE
))
3562 /* The AUTH command is not permitted to occur inside a transaction, and may
3563 occur successfully only once per connection. Actually, that isn't quite
3564 true. When TLS is started, all previous information about a connection must
3565 be discarded, so a new AUTH is permitted at that time.
3567 AUTH may only be used when it has been advertised. However, it seems that
3568 there are clients that send AUTH when it hasn't been advertised, some of
3569 them even doing this after HELO. And there are MTAs that accept this. Sigh.
3570 So there's a get-out that allows this to happen.
3572 AUTH is initially labelled as a "nonmail command" so that one occurrence
3573 doesn't get counted. We change the label here so that multiple failing
3574 AUTHS will eventually hit the nonmail threshold. */
3578 authentication_failed
= TRUE
;
3579 cmd_list
[CMD_LIST_AUTH
].is_mail_cmd
= FALSE
;
3581 if (!auth_advertised
&& !allow_auth_unadvertised
)
3583 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3584 US
"AUTH command used when not advertised");
3587 if (sender_host_authenticated
)
3589 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3590 US
"already authenticated");
3595 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3596 US
"not permitted in mail transaction");
3603 && (rc
= acl_check(ACL_WHERE_AUTH
, NULL
, acl_smtp_auth
,
3604 &user_msg
, &log_msg
)) != OK
3607 done
= smtp_handle_acl_fail(ACL_WHERE_AUTH
, rc
, user_msg
, log_msg
);
3611 /* Find the name of the requested authentication mechanism. */
3614 while ((c
= *smtp_cmd_data
) != 0 && !isspace(c
))
3616 if (!isalnum(c
) && c
!= '-' && c
!= '_')
3618 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
3619 US
"invalid character in authentication mechanism name");
3625 /* If not at the end of the line, we must be at white space. Terminate the
3626 name and move the pointer on to any data that may be present. */
3628 if (*smtp_cmd_data
!= 0)
3630 *smtp_cmd_data
++ = 0;
3631 while (isspace(*smtp_cmd_data
)) smtp_cmd_data
++;
3634 /* Search for an authentication mechanism which is configured for use
3635 as a server and which has been advertised (unless, sigh, allow_auth_
3636 unadvertised is set). */
3638 for (au
= auths
; au
; au
= au
->next
)
3639 if (strcmpic(s
, au
->public_name
) == 0 && au
->server
&&
3640 (au
->advertised
|| allow_auth_unadvertised
))
3645 c
= smtp_in_auth(au
, &s
, &ss
);
3647 smtp_printf("%s\r\n", s
);
3649 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s authenticator failed for %s: %s",
3650 au
->name
, host_and_ident(FALSE
), ss
);
3653 done
= synprot_error(L_smtp_protocol_error
, 504, NULL
,
3654 string_sprintf("%s authentication mechanism not supported", s
));
3656 break; /* AUTH_CMD */
3658 /* The HELO/EHLO commands are permitted to appear in the middle of a
3659 session as well as at the beginning. They have the effect of a reset in
3660 addition to their other functions. Their absence at the start cannot be
3661 taken to be an error.
3665 If the EHLO command is not acceptable to the SMTP server, 501, 500,
3666 or 502 failure replies MUST be returned as appropriate. The SMTP
3667 server MUST stay in the same state after transmitting these replies
3668 that it was in before the EHLO was received.
3670 Therefore, we do not do the reset until after checking the command for
3671 acceptability. This change was made for Exim release 4.11. Previously
3672 it did the reset first. */
3685 HELO_EHLO
: /* Common code for HELO and EHLO */
3686 cmd_list
[CMD_LIST_HELO
].is_mail_cmd
= FALSE
;
3687 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= FALSE
;
3689 /* Reject the HELO if its argument was invalid or non-existent. A
3690 successful check causes the argument to be saved in malloc store. */
3692 if (!check_helo(smtp_cmd_data
))
3694 smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello
);
3696 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected %s from %s: syntactically "
3697 "invalid argument(s): %s", hello
, host_and_ident(FALSE
),
3698 (*smtp_cmd_argument
== 0)? US
"(no argument given)" :
3699 string_printing(smtp_cmd_argument
));
3701 if (++synprot_error_count
> smtp_max_synprot_errors
)
3703 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
3704 "syntax or protocol errors (last command was \"%s\")",
3705 host_and_ident(FALSE
), string_printing(smtp_cmd_buffer
));
3712 /* If sender_host_unknown is true, we have got here via the -bs interface,
3713 not called from inetd. Otherwise, we are running an IP connection and the
3714 host address will be set. If the helo name is the primary name of this
3715 host and we haven't done a reverse lookup, force one now. If helo_required
3716 is set, ensure that the HELO name matches the actual host. If helo_verify
3717 is set, do the same check, but softly. */
3719 if (!sender_host_unknown
)
3721 BOOL old_helo_verified
= helo_verified
;
3722 uschar
*p
= smtp_cmd_data
;
3724 while (*p
!= 0 && !isspace(*p
)) { *p
= tolower(*p
); p
++; }
3727 /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
3728 because otherwise the log can be confusing. */
3730 if (sender_host_name
== NULL
&&
3731 (deliver_domain
= sender_helo_name
, /* set $domain */
3732 match_isinlist(sender_helo_name
, CUSS
&helo_lookup_domains
, 0,
3733 &domainlist_anchor
, NULL
, MCL_DOMAIN
, TRUE
, NULL
)) == OK
)
3734 (void)host_name_lookup();
3736 /* Rebuild the fullhost info to include the HELO name (and the real name
3737 if it was looked up.) */
3739 host_build_sender_fullhost(); /* Rebuild */
3740 set_process_info("handling%s incoming connection from %s",
3741 (tls_in
.active
>= 0)? " TLS" : "", host_and_ident(FALSE
));
3743 /* Verify if configured. This doesn't give much security, but it does
3744 make some people happy to be able to do it. If helo_required is set,
3745 (host matches helo_verify_hosts) failure forces rejection. If helo_verify
3746 is set (host matches helo_try_verify_hosts), it does not. This is perhaps
3747 now obsolescent, since the verification can now be requested selectively
3750 helo_verified
= helo_verify_failed
= sender_helo_dnssec
= FALSE
;
3751 if (helo_required
|| helo_verify
)
3753 BOOL tempfail
= !smtp_verify_helo();
3758 smtp_printf("%d %s argument does not match calling host\r\n",
3759 tempfail
? 451 : 550, hello
);
3760 log_write(0, LOG_MAIN
|LOG_REJECT
, "%srejected \"%s %s\" from %s",
3761 tempfail
? "temporarily " : "",
3762 hello
, sender_helo_name
, host_and_ident(FALSE
));
3763 helo_verified
= old_helo_verified
;
3764 break; /* End of HELO/EHLO processing */
3766 HDEBUG(D_all
) debug_printf("%s verification failed but host is in "
3767 "helo_try_verify_hosts\n", hello
);
3772 #ifdef EXPERIMENTAL_SPF
3773 /* set up SPF context */
3774 spf_init(sender_helo_name
, sender_host_address
);
3777 /* Apply an ACL check if one is defined; afterwards, recheck
3778 synchronization in case the client started sending in a delay. */
3781 if ((rc
= acl_check(ACL_WHERE_HELO
, NULL
, acl_smtp_helo
,
3782 &user_msg
, &log_msg
)) != OK
)
3784 done
= smtp_handle_acl_fail(ACL_WHERE_HELO
, rc
, user_msg
, log_msg
);
3785 sender_helo_name
= NULL
;
3786 host_build_sender_fullhost(); /* Rebuild */
3789 else if (!check_sync()) goto SYNC_FAILURE
;
3791 /* Generate an OK reply. The default string includes the ident if present,
3792 and also the IP address if present. Reflecting back the ident is intended
3793 as a deterrent to mail forgers. For maximum efficiency, and also because
3794 some broken systems expect each response to be in a single packet, arrange
3795 that the entire reply is sent in one write(). */
3797 auth_advertised
= FALSE
;
3798 pipelining_advertised
= FALSE
;
3800 tls_advertised
= FALSE
;
3802 dsn_advertised
= FALSE
;
3804 smtputf8_advertised
= FALSE
;
3807 smtp_code
= US
"250 "; /* Default response code plus space*/
3808 if (user_msg
== NULL
)
3810 s
= string_sprintf("%.3s %s Hello %s%s%s",
3812 smtp_active_hostname
,
3813 (sender_ident
== NULL
)? US
"" : sender_ident
,
3814 (sender_ident
== NULL
)? US
"" : US
" at ",
3815 (sender_host_name
== NULL
)? sender_helo_name
: sender_host_name
);
3820 if (sender_host_address
!= NULL
)
3822 s
= string_catn(s
, &size
, &ptr
, US
" [", 2);
3823 s
= string_cat (s
, &size
, &ptr
, sender_host_address
);
3824 s
= string_catn(s
, &size
, &ptr
, US
"]", 1);
3828 /* A user-supplied EHLO greeting may not contain more than one line. Note
3829 that the code returned by smtp_message_code() includes the terminating
3830 whitespace character. */
3836 smtp_message_code(&smtp_code
, &codelen
, &user_msg
, NULL
, TRUE
);
3837 s
= string_sprintf("%.*s%s", codelen
, smtp_code
, user_msg
);
3838 if ((ss
= strpbrk(CS s
, "\r\n")) != NULL
)
3840 log_write(0, LOG_MAIN
|LOG_PANIC
, "EHLO/HELO response must not contain "
3841 "newlines: message truncated: %s", string_printing(s
));
3848 s
= string_catn(s
, &size
, &ptr
, US
"\r\n", 2);
3850 /* If we received EHLO, we must create a multiline response which includes
3851 the functions supported. */
3857 /* I'm not entirely happy with this, as an MTA is supposed to check
3858 that it has enough room to accept a message of maximum size before
3859 it sends this. However, there seems little point in not sending it.
3860 The actual size check happens later at MAIL FROM time. By postponing it
3861 till then, VRFY and EXPN can be used after EHLO when space is short. */
3863 if (thismessage_size_limit
> 0)
3865 sprintf(CS big_buffer
, "%.3s-SIZE %d\r\n", smtp_code
,
3866 thismessage_size_limit
);
3867 s
= string_cat(s
, &size
, &ptr
, big_buffer
);
3871 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3872 s
= string_catn(s
, &size
, &ptr
, US
"-SIZE\r\n", 7);
3875 /* Exim does not do protocol conversion or data conversion. It is 8-bit
3876 clean; if it has an 8-bit character in its hand, it just sends it. It
3877 cannot therefore specify 8BITMIME and remain consistent with the RFCs.
3878 However, some users want this option simply in order to stop MUAs
3879 mangling messages that contain top-bit-set characters. It is therefore
3880 provided as an option. */
3882 if (accept_8bitmime
)
3884 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3885 s
= string_catn(s
, &size
, &ptr
, US
"-8BITMIME\r\n", 11);
3888 /* Advertise DSN support if configured to do so. */
3889 if (verify_check_host(&dsn_advertise_hosts
) != FAIL
)
3891 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3892 s
= string_catn(s
, &size
, &ptr
, US
"-DSN\r\n", 6);
3893 dsn_advertised
= TRUE
;
3896 /* Advertise ETRN if there's an ACL checking whether a host is
3897 permitted to issue it; a check is made when any host actually tries. */
3899 if (acl_smtp_etrn
!= NULL
)
3901 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3902 s
= string_catn(s
, &size
, &ptr
, US
"-ETRN\r\n", 7);
3905 /* Advertise EXPN if there's an ACL checking whether a host is
3906 permitted to issue it; a check is made when any host actually tries. */
3908 if (acl_smtp_expn
!= NULL
)
3910 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3911 s
= string_catn(s
, &size
, &ptr
, US
"-EXPN\r\n", 7);
3914 /* Exim is quite happy with pipelining, so let the other end know that
3915 it is safe to use it, unless advertising is disabled. */
3917 if (pipelining_enable
&&
3918 verify_check_host(&pipelining_advertise_hosts
) == OK
)
3920 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3921 s
= string_catn(s
, &size
, &ptr
, US
"-PIPELINING\r\n", 13);
3922 sync_cmd_limit
= NON_SYNC_CMD_PIPELINING
;
3923 pipelining_advertised
= TRUE
;
3927 /* If any server authentication mechanisms are configured, advertise
3928 them if the current host is in auth_advertise_hosts. The problem with
3929 advertising always is that some clients then require users to
3930 authenticate (and aren't configurable otherwise) even though it may not
3931 be necessary (e.g. if the host is in host_accept_relay).
3933 RFC 2222 states that SASL mechanism names contain only upper case
3934 letters, so output the names in upper case, though we actually recognize
3935 them in either case in the AUTH command. */
3938 #if defined(SUPPORT_TLS) && defined(AUTH_TLS)
3939 && !sender_host_authenticated
3941 && verify_check_host(&auth_advertise_hosts
) == OK
3946 for (au
= auths
; au
; au
= au
->next
)
3947 if (au
->server
&& (au
->advertise_condition
== NULL
||
3948 expand_check_condition(au
->advertise_condition
, au
->name
,
3949 US
"authenticator")))
3954 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3955 s
= string_catn(s
, &size
, &ptr
, US
"-AUTH", 5);
3957 auth_advertised
= TRUE
;
3960 s
= string_catn(s
, &size
, &ptr
, US
" ", 1);
3961 s
= string_cat (s
, &size
, &ptr
, au
->public_name
);
3962 while (++saveptr
< ptr
) s
[saveptr
] = toupper(s
[saveptr
]);
3963 au
->advertised
= TRUE
;
3966 au
->advertised
= FALSE
;
3968 if (!first
) s
= string_catn(s
, &size
, &ptr
, US
"\r\n", 2);
3971 /* RFC 3030 CHUNKING */
3973 if (verify_check_host(&chunking_advertise_hosts
) != FAIL
)
3975 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3976 s
= string_catn(s
, &size
, &ptr
, US
"-CHUNKING\r\n", 11);
3977 chunking_offered
= TRUE
;
3978 chunking_state
= CHUNKING_OFFERED
;
3981 /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
3982 if it has been included in the binary, and the host matches
3983 tls_advertise_hosts. We must *not* advertise if we are already in a
3984 secure connection. */
3987 if (tls_in
.active
< 0 &&
3988 verify_check_host(&tls_advertise_hosts
) != FAIL
)
3990 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3991 s
= string_catn(s
, &size
, &ptr
, US
"-STARTTLS\r\n", 11);
3992 tls_advertised
= TRUE
;
3996 #ifndef DISABLE_PRDR
3997 /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */
4000 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
4001 s
= string_catn(s
, &size
, &ptr
, US
"-PRDR\r\n", 7);
4006 if ( accept_8bitmime
4007 && verify_check_host(&smtputf8_advertise_hosts
) != FAIL
)
4009 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
4010 s
= string_catn(s
, &size
, &ptr
, US
"-SMTPUTF8\r\n", 11);
4011 smtputf8_advertised
= TRUE
;
4015 /* Finish off the multiline reply with one that is always available. */
4017 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
4018 s
= string_catn(s
, &size
, &ptr
, US
" HELP\r\n", 7);
4021 /* Terminate the string (for debug), write it, and note that HELO/EHLO
4027 if (tls_in
.active
>= 0) (void)tls_write(TRUE
, s
, ptr
); else
4031 int i
= fwrite(s
, 1, ptr
, smtp_out
); i
= i
; /* compiler quietening */
4036 while ((cr
= Ustrchr(s
, '\r')) != NULL
) /* lose CRs */
4037 memmove(cr
, cr
+ 1, (ptr
--) - (cr
- s
));
4038 debug_printf("SMTP>> %s", s
);
4042 /* Reset the protocol and the state, abandoning any previous message. */
4044 (sender_host_address
? protocols
: protocols_local
)
4046 ? pextend
+ (sender_host_authenticated
? pauthed
: 0)
4048 + (tls_in
.active
>= 0 ? pcrpted
: 0)
4050 smtp_reset(reset_point
);
4052 break; /* HELO/EHLO */
4055 /* The MAIL command requires an address as an operand. All we do
4056 here is to parse it for syntactic correctness. The form "<>" is
4057 a special case which converts into an empty string. The start/end
4058 pointers in the original are not used further for this address, as
4059 it is the canonical extracted address which is all that is kept. */
4063 smtp_mailcmd_count
++; /* Count for limit and ratelimit */
4064 was_rej_mail
= TRUE
; /* Reset if accepted */
4065 env_mail_type_t
* mail_args
; /* Sanity check & validate args */
4067 if (helo_required
&& !helo_seen
)
4069 smtp_printf("503 HELO or EHLO required\r\n");
4070 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected MAIL from %s: no "
4071 "HELO/EHLO given", host_and_ident(FALSE
));
4075 if (sender_address
!= NULL
)
4077 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4078 US
"sender already given");
4082 if (smtp_cmd_data
[0] == 0)
4084 done
= synprot_error(L_smtp_protocol_error
, 501, NULL
,
4085 US
"MAIL must have an address operand");
4089 /* Check to see if the limit for messages per connection would be
4090 exceeded by accepting further messages. */
4092 if (smtp_accept_max_per_connection
> 0 &&
4093 smtp_mailcmd_count
> smtp_accept_max_per_connection
)
4095 smtp_printf("421 too many messages in this connection\r\n");
4096 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected MAIL command %s: too many "
4097 "messages in one connection", host_and_ident(TRUE
));
4101 /* Reset for start of message - even if this is going to fail, we
4102 obviously need to throw away any previous data. */
4104 smtp_reset(reset_point
);
4106 sender_data
= recipient_data
= NULL
;
4108 /* Loop, checking for ESMTP additions to the MAIL FROM command. */
4112 uschar
*name
, *value
, *end
;
4113 unsigned long int size
;
4114 BOOL arg_error
= FALSE
;
4116 if (!extract_option(&name
, &value
)) break;
4118 for (mail_args
= env_mail_type_list
;
4119 mail_args
->value
!= ENV_MAIL_OPT_NULL
;
4122 if (strcmpic(name
, mail_args
->name
) == 0)
4124 if (mail_args
->need_value
&& strcmpic(value
, US
"") == 0)
4127 switch(mail_args
->value
)
4129 /* Handle SIZE= by reading the value. We don't do the check till later,
4130 in order to be able to log the sender address on failure. */
4131 case ENV_MAIL_OPT_SIZE
:
4132 if (((size
= Ustrtoul(value
, &end
, 10)), *end
== 0))
4134 if ((size
== ULONG_MAX
&& errno
== ERANGE
) || size
> INT_MAX
)
4136 message_size
= (int)size
;
4142 /* If this session was initiated with EHLO and accept_8bitmime is set,
4143 Exim will have indicated that it supports the BODY=8BITMIME option. In
4144 fact, it does not support this according to the RFCs, in that it does not
4145 take any special action for forwarding messages containing 8-bit
4146 characters. That is why accept_8bitmime is not the default setting, but
4147 some sites want the action that is provided. We recognize both "8BITMIME"
4148 and "7BIT" as body types, but take no action. */
4149 case ENV_MAIL_OPT_BODY
:
4150 if (accept_8bitmime
) {
4151 if (strcmpic(value
, US
"8BITMIME") == 0)
4153 else if (strcmpic(value
, US
"7BIT") == 0)
4158 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4159 US
"invalid data for BODY");
4162 DEBUG(D_receive
) debug_printf("8BITMIME: %d\n", body_8bitmime
);
4168 /* Handle the two DSN options, but only if configured to do so (which
4169 will have caused "DSN" to be given in the EHLO response). The code itself
4170 is included only if configured in at build time. */
4172 case ENV_MAIL_OPT_RET
:
4175 /* Check if RET has already been set */
4178 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4179 US
"RET can be specified once only");
4182 dsn_ret
= strcmpic(value
, US
"HDRS") == 0
4184 : strcmpic(value
, US
"FULL") == 0
4187 DEBUG(D_receive
) debug_printf("DSN_RET: %d\n", dsn_ret
);
4188 /* Check for invalid invalid value, and exit with error */
4191 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4192 US
"Value for RET is invalid");
4197 case ENV_MAIL_OPT_ENVID
:
4200 /* Check if the dsn envid has been already set */
4201 if (dsn_envid
!= NULL
)
4203 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4204 US
"ENVID can be specified once only");
4207 dsn_envid
= string_copy(value
);
4208 DEBUG(D_receive
) debug_printf("DSN_ENVID: %s\n", dsn_envid
);
4212 /* Handle the AUTH extension. If the value given is not "<>" and either
4213 the ACL says "yes" or there is no ACL but the sending host is
4214 authenticated, we set it up as the authenticated sender. However, if the
4215 authenticator set a condition to be tested, we ignore AUTH on MAIL unless
4216 the condition is met. The value of AUTH is an xtext, which means that +,
4217 = and cntrl chars are coded in hex; however "<>" is unaffected by this
4219 case ENV_MAIL_OPT_AUTH
:
4220 if (Ustrcmp(value
, "<>") != 0)
4225 if (auth_xtextdecode(value
, &authenticated_sender
) < 0)
4227 /* Put back terminator overrides for error message */
4230 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4231 US
"invalid data for AUTH");
4234 if (acl_smtp_mailauth
== NULL
)
4236 ignore_msg
= US
"client not authenticated";
4237 rc
= (sender_host_authenticated
!= NULL
)? OK
: FAIL
;
4241 ignore_msg
= US
"rejected by ACL";
4242 rc
= acl_check(ACL_WHERE_MAILAUTH
, NULL
, acl_smtp_mailauth
,
4243 &user_msg
, &log_msg
);
4249 if (authenticated_by
== NULL
||
4250 authenticated_by
->mail_auth_condition
== NULL
||
4251 expand_check_condition(authenticated_by
->mail_auth_condition
,
4252 authenticated_by
->name
, US
"authenticator"))
4253 break; /* Accept the AUTH */
4255 ignore_msg
= US
"server_mail_auth_condition failed";
4256 if (authenticated_id
!= NULL
)
4257 ignore_msg
= string_sprintf("%s: authenticated ID=\"%s\"",
4258 ignore_msg
, authenticated_id
);
4263 authenticated_sender
= NULL
;
4264 log_write(0, LOG_MAIN
, "ignoring AUTH=%s from %s (%s)",
4265 value
, host_and_ident(TRUE
), ignore_msg
);
4268 /* Should only get DEFER or ERROR here. Put back terminator
4269 overrides for error message */
4274 (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH
, rc
, user_msg
,
4281 #ifndef DISABLE_PRDR
4282 case ENV_MAIL_OPT_PRDR
:
4284 prdr_requested
= TRUE
;
4289 case ENV_MAIL_OPT_UTF8
:
4290 if (smtputf8_advertised
)
4292 DEBUG(D_receive
) debug_printf("smtputf8 requested\n");
4293 message_smtputf8
= allow_utf8_domains
= TRUE
;
4294 received_protocol
= string_sprintf("utf8%s", received_protocol
);
4298 /* No valid option. Stick back the terminator characters and break
4299 the loop. Do the name-terminator second as extract_option sets
4300 value==name when it found no equal-sign.
4301 An error for a malformed address will occur. */
4302 case ENV_MAIL_OPT_NULL
:
4310 /* Break out of for loop if switch() had bad argument or
4311 when start of the email address is reached */
4312 if (arg_error
) break;
4315 /* If we have passed the threshold for rate limiting, apply the current
4316 delay, and update it for next time, provided this is a limited host. */
4318 if (smtp_mailcmd_count
> smtp_rlm_threshold
&&
4319 verify_check_host(&smtp_ratelimit_hosts
) == OK
)
4321 DEBUG(D_receive
) debug_printf("rate limit MAIL: delay %.3g sec\n",
4322 smtp_delay_mail
/1000.0);
4323 millisleep((int)smtp_delay_mail
);
4324 smtp_delay_mail
*= smtp_rlm_factor
;
4325 if (smtp_delay_mail
> (double)smtp_rlm_limit
)
4326 smtp_delay_mail
= (double)smtp_rlm_limit
;
4329 /* Now extract the address, first applying any SMTP-time rewriting. The
4330 TRUE flag allows "<>" as a sender address. */
4332 raw_sender
= rewrite_existflags
& rewrite_smtp
4333 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
4334 global_rewrite_rules
)
4338 parse_extract_address(raw_sender
, &errmess
, &start
, &end
, &sender_domain
,
4343 done
= synprot_error(L_smtp_syntax_error
, 501, smtp_cmd_data
, errmess
);
4347 sender_address
= raw_sender
;
4349 /* If there is a configured size limit for mail, check that this message
4350 doesn't exceed it. The check is postponed to this point so that the sender
4353 if (thismessage_size_limit
> 0 && message_size
> thismessage_size_limit
)
4355 smtp_printf("552 Message size exceeds maximum permitted\r\n");
4356 log_write(L_size_reject
,
4357 LOG_MAIN
|LOG_REJECT
, "rejected MAIL FROM:<%s> %s: "
4358 "message too big: size%s=%d max=%d",
4360 host_and_ident(TRUE
),
4361 (message_size
== INT_MAX
)? ">" : "",
4363 thismessage_size_limit
);
4364 sender_address
= NULL
;
4368 /* Check there is enough space on the disk unless configured not to.
4369 When smtp_check_spool_space is set, the check is for thismessage_size_limit
4370 plus the current message - i.e. we accept the message only if it won't
4371 reduce the space below the threshold. Add 5000 to the size to allow for
4372 overheads such as the Received: line and storing of recipients, etc.
4373 By putting the check here, even when SIZE is not given, it allow VRFY
4374 and EXPN etc. to be used when space is short. */
4376 if (!receive_check_fs(
4377 (smtp_check_spool_space
&& message_size
>= 0)?
4378 message_size
+ 5000 : 0))
4380 smtp_printf("452 Space shortage, please try later\r\n");
4381 sender_address
= NULL
;
4385 /* If sender_address is unqualified, reject it, unless this is a locally
4386 generated message, or the sending host or net is permitted to send
4387 unqualified addresses - typically local machines behaving as MUAs -
4388 in which case just qualify the address. The flag is set above at the start
4389 of the SMTP connection. */
4391 if (sender_domain
== 0 && sender_address
[0] != 0)
4393 if (allow_unqualified_sender
)
4395 sender_domain
= Ustrlen(sender_address
) + 1;
4396 sender_address
= rewrite_address_qualify(sender_address
, FALSE
);
4397 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
4402 smtp_printf("501 %s: sender address must contain a domain\r\n",
4404 log_write(L_smtp_syntax_error
,
4405 LOG_MAIN
|LOG_REJECT
,
4406 "unqualified sender rejected: <%s> %s%s",
4408 host_and_ident(TRUE
),
4410 sender_address
= NULL
;
4415 /* Apply an ACL check if one is defined, before responding. Afterwards,
4416 when pipelining is not advertised, do another sync check in case the ACL
4417 delayed and the client started sending in the meantime. */
4421 rc
= acl_check(ACL_WHERE_MAIL
, NULL
, acl_smtp_mail
, &user_msg
, &log_msg
);
4422 if (rc
== OK
&& !pipelining_advertised
&& !check_sync())
4428 if (rc
== OK
|| rc
== DISCARD
)
4431 smtp_printf("%s%s%s", US
"250 OK",
4432 #ifndef DISABLE_PRDR
4433 prdr_requested
? US
", PRDR Requested" : US
"",
4440 #ifndef DISABLE_PRDR
4442 user_msg
= string_sprintf("%s%s", user_msg
, US
", PRDR Requested");
4444 smtp_user_msg(US
"250", user_msg
);
4446 smtp_delay_rcpt
= smtp_rlr_base
;
4447 recipients_discarded
= (rc
== DISCARD
);
4448 was_rej_mail
= FALSE
;
4452 done
= smtp_handle_acl_fail(ACL_WHERE_MAIL
, rc
, user_msg
, log_msg
);
4453 sender_address
= NULL
;
4458 /* The RCPT command requires an address as an operand. There may be any
4459 number of RCPT commands, specifying multiple recipients. We build them all
4460 into a data structure. The start/end values given by parse_extract_address
4461 are not used, as we keep only the extracted address. */
4466 was_rcpt
= rcpt_in_progress
= TRUE
;
4468 /* There must be a sender address; if the sender was rejected and
4469 pipelining was advertised, we assume the client was pipelining, and do not
4470 count this as a protocol error. Reset was_rej_mail so that further RCPTs
4471 get the same treatment. */
4473 if (sender_address
== NULL
)
4475 if (pipelining_advertised
&& last_was_rej_mail
)
4477 smtp_printf("503 sender not yet given\r\n");
4478 was_rej_mail
= TRUE
;
4482 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4483 US
"sender not yet given");
4484 was_rcpt
= FALSE
; /* Not a valid RCPT */
4490 /* Check for an operand */
4492 if (smtp_cmd_data
[0] == 0)
4494 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4495 US
"RCPT must have an address operand");
4500 /* Set the DSN flags orcpt and dsn_flags from the session*/
4506 uschar
*name
, *value
;
4508 if (!extract_option(&name
, &value
))
4511 if (dsn_advertised
&& strcmpic(name
, US
"ORCPT") == 0)
4513 /* Check whether orcpt has been already set */
4516 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4517 US
"ORCPT can be specified once only");
4520 orcpt
= string_copy(value
);
4521 DEBUG(D_receive
) debug_printf("DSN orcpt: %s\n", orcpt
);
4524 else if (dsn_advertised
&& strcmpic(name
, US
"NOTIFY") == 0)
4526 /* Check if the notify flags have been already set */
4529 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4530 US
"NOTIFY can be specified once only");
4533 if (strcmpic(value
, US
"NEVER") == 0)
4534 flags
|= rf_notify_never
;
4541 while (*pp
!= 0 && *pp
!= ',') pp
++;
4542 if (*pp
== ',') *pp
++ = 0;
4543 if (strcmpic(p
, US
"SUCCESS") == 0)
4545 DEBUG(D_receive
) debug_printf("DSN: Setting notify success\n");
4546 flags
|= rf_notify_success
;
4548 else if (strcmpic(p
, US
"FAILURE") == 0)
4550 DEBUG(D_receive
) debug_printf("DSN: Setting notify failure\n");
4551 flags
|= rf_notify_failure
;
4553 else if (strcmpic(p
, US
"DELAY") == 0)
4555 DEBUG(D_receive
) debug_printf("DSN: Setting notify delay\n");
4556 flags
|= rf_notify_delay
;
4560 /* Catch any strange values */
4561 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4562 US
"Invalid value for NOTIFY parameter");
4567 DEBUG(D_receive
) debug_printf("DSN Flags: %x\n", flags
);
4571 /* Unknown option. Stick back the terminator characters and break
4572 the loop. An error for a malformed address will occur. */
4576 DEBUG(D_receive
) debug_printf("Invalid RCPT option: %s : %s\n", name
, value
);
4583 /* Apply SMTP rewriting then extract the working address. Don't allow "<>"
4584 as a recipient address */
4586 recipient
= rewrite_existflags
& rewrite_smtp
4587 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
4588 global_rewrite_rules
)
4591 if (!(recipient
= parse_extract_address(recipient
, &errmess
, &start
, &end
,
4592 &recipient_domain
, FALSE
)))
4594 done
= synprot_error(L_smtp_syntax_error
, 501, smtp_cmd_data
, errmess
);
4599 /* If the recipient address is unqualified, reject it, unless this is a
4600 locally generated message. However, unqualified addresses are permitted
4601 from a configured list of hosts and nets - typically when behaving as
4602 MUAs rather than MTAs. Sad that SMTP is used for both types of traffic,
4603 really. The flag is set at the start of the SMTP connection.
4605 RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always
4606 assumed this meant "reserved local part", but the revision of RFC 821 and
4607 friends now makes it absolutely clear that it means *mailbox*. Consequently
4608 we must always qualify this address, regardless. */
4610 if (recipient_domain
== 0)
4611 if (!(recipient_domain
= qualify_recipient(&recipient
, smtp_cmd_data
,
4618 /* Check maximum allowed */
4620 if (rcpt_count
> recipients_max
&& recipients_max
> 0)
4622 if (recipients_max_reject
)
4625 smtp_printf("552 too many recipients\r\n");
4627 log_write(0, LOG_MAIN
|LOG_REJECT
, "too many recipients: message "
4628 "rejected: sender=<%s> %s", sender_address
, host_and_ident(TRUE
));
4633 smtp_printf("452 too many recipients\r\n");
4635 log_write(0, LOG_MAIN
|LOG_REJECT
, "too many recipients: excess "
4636 "temporarily rejected: sender=<%s> %s", sender_address
,
4637 host_and_ident(TRUE
));
4644 /* If we have passed the threshold for rate limiting, apply the current
4645 delay, and update it for next time, provided this is a limited host. */
4647 if (rcpt_count
> smtp_rlr_threshold
&&
4648 verify_check_host(&smtp_ratelimit_hosts
) == OK
)
4650 DEBUG(D_receive
) debug_printf("rate limit RCPT: delay %.3g sec\n",
4651 smtp_delay_rcpt
/1000.0);
4652 millisleep((int)smtp_delay_rcpt
);
4653 smtp_delay_rcpt
*= smtp_rlr_factor
;
4654 if (smtp_delay_rcpt
> (double)smtp_rlr_limit
)
4655 smtp_delay_rcpt
= (double)smtp_rlr_limit
;
4658 /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
4659 for them. Otherwise, check the access control list for this recipient. As
4660 there may be a delay in this, re-check for a synchronization error
4661 afterwards, unless pipelining was advertised. */
4663 if (recipients_discarded
) rc
= DISCARD
; else
4665 rc
= acl_check(ACL_WHERE_RCPT
, recipient
, acl_smtp_rcpt
, &user_msg
,
4667 if (rc
== OK
&& !pipelining_advertised
&& !check_sync())
4671 /* The ACL was happy */
4675 if (user_msg
== NULL
) smtp_printf("250 Accepted\r\n");
4676 else smtp_user_msg(US
"250", user_msg
);
4677 receive_add_recipient(recipient
, -1);
4679 /* Set the dsn flags in the recipients_list */
4680 recipients_list
[recipients_count
-1].orcpt
= orcpt
;
4681 recipients_list
[recipients_count
-1].dsn_flags
= flags
;
4683 DEBUG(D_receive
) debug_printf("DSN: orcpt: %s flags: %d\n",
4684 recipients_list
[recipients_count
-1].orcpt
,
4685 recipients_list
[recipients_count
-1].dsn_flags
);
4688 /* The recipient was discarded */
4690 else if (rc
== DISCARD
)
4692 if (user_msg
== NULL
) smtp_printf("250 Accepted\r\n");
4693 else smtp_user_msg(US
"250", user_msg
);
4696 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s F=<%s> RCPT %s: "
4697 "discarded by %s ACL%s%s", host_and_ident(TRUE
),
4698 sender_address_unrewritten
? sender_address_unrewritten
: sender_address
,
4699 smtp_cmd_argument
, recipients_discarded
? "MAIL" : "RCPT",
4700 log_msg
? US
": " : US
"", log_msg
? log_msg
: US
"");
4703 /* Either the ACL failed the address, or it was deferred. */
4707 if (rc
== FAIL
) rcpt_fail_count
++; else rcpt_defer_count
++;
4708 done
= smtp_handle_acl_fail(ACL_WHERE_RCPT
, rc
, user_msg
, log_msg
);
4713 /* The DATA command is legal only if it follows successful MAIL FROM
4714 and RCPT TO commands. However, if pipelining is advertised, a bad DATA is
4715 not counted as a protocol error if it follows RCPT (which must have been
4716 rejected if there are no recipients.) This function is complete when a
4717 valid DATA command is encountered.
4719 Note concerning the code used: RFC 2821 says this:
4721 - If there was no MAIL, or no RCPT, command, or all such commands
4722 were rejected, the server MAY return a "command out of sequence"
4723 (503) or "no valid recipients" (554) reply in response to the
4726 The example in the pipelining RFC 2920 uses 554, but I use 503 here
4727 because it is the same whether pipelining is in use or not.
4729 If all the RCPT commands that precede DATA provoked the same error message
4730 (often indicating some kind of system error), it is helpful to include it
4731 with the DATA rejection (an idea suggested by Tony Finch). */
4738 if (chunking_state
!= CHUNKING_OFFERED
)
4740 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4741 US
"BDAT command used when CHUNKING not advertised");
4745 /* grab size, endmarker */
4747 if (sscanf(CS smtp_cmd_data
, "%u %n", &chunking_datasize
, &n
) < 1)
4749 done
= synprot_error(L_smtp_protocol_error
, 501, NULL
,
4750 US
"missing size for BDAT command");
4753 chunking_state
= strcmpic(smtp_cmd_data
+n
, US
"LAST") == 0
4754 ? CHUNKING_LAST
: CHUNKING_ACTIVE
;
4755 chunking_data_left
= chunking_datasize
;
4757 lwr_receive_getc
= receive_getc
;
4758 lwr_receive_ungetc
= receive_ungetc
;
4759 receive_getc
= bdat_getc
;
4760 receive_ungetc
= bdat_ungetc
;
4763 debug_printf("chunking state %d\n", (int)chunking_state
);
4770 DATA_BDAT
: /* Common code for DATA and BDAT */
4771 if (!discarded
&& recipients_count
<= 0)
4773 if (rcpt_smtp_response_same
&& rcpt_smtp_response
!= NULL
)
4775 uschar
*code
= US
"503";
4776 int len
= Ustrlen(rcpt_smtp_response
);
4777 smtp_respond(code
, 3, FALSE
, US
"All RCPT commands were rejected with "
4779 /* Responses from smtp_printf() will have \r\n on the end */
4780 if (len
> 2 && rcpt_smtp_response
[len
-2] == '\r')
4781 rcpt_smtp_response
[len
-2] = 0;
4782 smtp_respond(code
, 3, FALSE
, rcpt_smtp_response
);
4784 if (pipelining_advertised
&& last_was_rcpt
)
4785 smtp_printf("503 Valid RCPT command must precede %s\r\n",
4786 smtp_names
[smtp_connection_had
[smtp_ch_index
-1]]);
4788 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4789 smtp_connection_had
[smtp_ch_index
-1] == SCH_DATA
4790 ? US
"valid RCPT command must precede DATA"
4791 : US
"valid RCPT command must precede BDAT");
4793 if (chunking_state
> CHUNKING_OFFERED
)
4798 if (toomany
&& recipients_max_reject
)
4800 sender_address
= NULL
; /* This will allow a new MAIL without RSET */
4801 sender_address_unrewritten
= NULL
;
4802 smtp_printf("554 Too many recipients\r\n");
4806 if (chunking_state
> CHUNKING_OFFERED
)
4807 { /* No predata ACL or go-ahead output for BDAT */
4812 /* If there is an ACL, re-check the synchronization afterwards, since the
4813 ACL may have delayed. To handle cutthrough delivery enforce a dummy call
4814 to get the DATA command sent. */
4816 if (acl_smtp_predata
== NULL
&& cutthrough
.fd
< 0)
4820 uschar
* acl
= acl_smtp_predata
? acl_smtp_predata
: US
"accept";
4821 enable_dollar_recipients
= TRUE
;
4822 rc
= acl_check(ACL_WHERE_PREDATA
, NULL
, acl
, &user_msg
,
4824 enable_dollar_recipients
= FALSE
;
4825 if (rc
== OK
&& !check_sync())
4829 { /* Either the ACL failed the address, or it was deferred. */
4830 done
= smtp_handle_acl_fail(ACL_WHERE_PREDATA
, rc
, user_msg
, log_msg
);
4836 smtp_user_msg(US
"354", user_msg
);
4839 "354 Enter message, ending with \".\" on a line by itself\r\n");
4843 message_ended
= END_NOTENDED
; /* Indicate in middle of data */
4854 if (!(address
= parse_extract_address(smtp_cmd_data
, &errmess
,
4855 &start
, &end
, &recipient_domain
, FALSE
)))
4857 smtp_printf("501 %s\r\n", errmess
);
4861 if (recipient_domain
== 0)
4862 if (!(recipient_domain
= qualify_recipient(&address
, smtp_cmd_data
,
4866 if ((rc
= acl_check(ACL_WHERE_VRFY
, address
, acl_smtp_vrfy
,
4867 &user_msg
, &log_msg
)) != OK
)
4868 done
= smtp_handle_acl_fail(ACL_WHERE_VRFY
, rc
, user_msg
, log_msg
);
4872 address_item
* addr
= deliver_make_addr(address
, FALSE
);
4874 switch(verify_address(addr
, NULL
, vopt_is_recipient
| vopt_qualify
, -1,
4875 -1, -1, NULL
, NULL
, NULL
))
4878 s
= string_sprintf("250 <%s> is deliverable", address
);
4882 s
= (addr
->user_message
!= NULL
)?
4883 string_sprintf("451 <%s> %s", address
, addr
->user_message
) :
4884 string_sprintf("451 Cannot resolve <%s> at this time", address
);
4888 s
= (addr
->user_message
!= NULL
)?
4889 string_sprintf("550 <%s> %s", address
, addr
->user_message
) :
4890 string_sprintf("550 <%s> is not deliverable", address
);
4891 log_write(0, LOG_MAIN
, "VRFY failed for %s %s",
4892 smtp_cmd_argument
, host_and_ident(TRUE
));
4896 smtp_printf("%s\r\n", s
);
4904 rc
= acl_check(ACL_WHERE_EXPN
, NULL
, acl_smtp_expn
, &user_msg
, &log_msg
);
4906 done
= smtp_handle_acl_fail(ACL_WHERE_EXPN
, rc
, user_msg
, log_msg
);
4909 BOOL save_log_testing_mode
= log_testing_mode
;
4910 address_test_mode
= log_testing_mode
= TRUE
;
4911 (void) verify_address(deliver_make_addr(smtp_cmd_data
, FALSE
),
4912 smtp_out
, vopt_is_recipient
| vopt_qualify
| vopt_expn
, -1, -1, -1,
4914 address_test_mode
= FALSE
;
4915 log_testing_mode
= save_log_testing_mode
; /* true for -bh */
4924 if (!tls_advertised
)
4926 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4927 US
"STARTTLS command used when not advertised");
4931 /* Apply an ACL check if one is defined */
4933 if ( acl_smtp_starttls
4934 && (rc
= acl_check(ACL_WHERE_STARTTLS
, NULL
, acl_smtp_starttls
,
4935 &user_msg
, &log_msg
)) != OK
4938 done
= smtp_handle_acl_fail(ACL_WHERE_STARTTLS
, rc
, user_msg
, log_msg
);
4942 /* RFC 2487 is not clear on when this command may be sent, though it
4943 does state that all information previously obtained from the client
4944 must be discarded if a TLS session is started. It seems reasonble to
4945 do an implied RSET when STARTTLS is received. */
4947 incomplete_transaction_log(US
"STARTTLS");
4948 smtp_reset(reset_point
);
4950 cmd_list
[CMD_LIST_STARTTLS
].is_mail_cmd
= FALSE
;
4952 /* There's an attack where more data is read in past the STARTTLS command
4953 before TLS is negotiated, then assumed to be part of the secure session
4954 when used afterwards; we use segregated input buffers, so are not
4955 vulnerable, but we want to note when it happens and, for sheer paranoia,
4956 ensure that the buffer is "wiped".
4957 Pipelining sync checks will normally have protected us too, unless disabled
4958 by configuration. */
4960 if (receive_smtp_buffered())
4963 debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n");
4964 if (tls_in
.active
< 0)
4965 smtp_inend
= smtp_inptr
= smtp_inbuffer
;
4966 /* and if TLS is already active, tls_server_start() should fail */
4969 /* There is nothing we value in the input buffer and if TLS is succesfully
4970 negotiated, we won't use this buffer again; if TLS fails, we'll just read
4971 fresh content into it. The buffer contains arbitrary content from an
4972 untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n
4973 It seems safest to just wipe away the content rather than leave it as a
4974 target to jump to. */
4976 memset(smtp_inbuffer
, 0, in_buffer_size
);
4978 /* Attempt to start up a TLS session, and if successful, discard all
4979 knowledge that was obtained previously. At least, that's what the RFC says,
4980 and that's what happens by default. However, in order to work round YAEB,
4981 there is an option to remember the esmtp state. Sigh.
4983 We must allow for an extra EHLO command and an extra AUTH command after
4984 STARTTLS that don't add to the nonmail command count. */
4986 if ((rc
= tls_server_start(tls_require_ciphers
)) == OK
)
4988 if (!tls_remember_esmtp
)
4989 helo_seen
= esmtp
= auth_advertised
= pipelining_advertised
= FALSE
;
4990 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= TRUE
;
4991 cmd_list
[CMD_LIST_AUTH
].is_mail_cmd
= TRUE
;
4992 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= TRUE
;
4993 if (sender_helo_name
!= NULL
)
4995 store_free(sender_helo_name
);
4996 sender_helo_name
= NULL
;
4997 host_build_sender_fullhost(); /* Rebuild */
4998 set_process_info("handling incoming TLS connection from %s",
4999 host_and_ident(FALSE
));
5002 (sender_host_address
? protocols
: protocols_local
)
5004 ? pextend
+ (sender_host_authenticated
? pauthed
: 0)
5006 + (tls_in
.active
>= 0 ? pcrpted
: 0)
5009 sender_host_authenticated
= NULL
;
5010 authenticated_id
= NULL
;
5011 sync_cmd_limit
= NON_SYNC_CMD_NON_PIPELINING
;
5012 DEBUG(D_tls
) debug_printf("TLS active\n");
5013 break; /* Successful STARTTLS */
5016 /* Some local configuration problem was discovered before actually trying
5017 to do a TLS handshake; give a temporary error. */
5019 else if (rc
== DEFER
)
5021 smtp_printf("454 TLS currently unavailable\r\n");
5025 /* Hard failure. Reject everything except QUIT or closed connection. One
5026 cause for failure is a nested STARTTLS, in which case tls_in.active remains
5027 set, but we must still reject all incoming commands. */
5029 DEBUG(D_tls
) debug_printf("TLS failed to start\n");
5032 switch(smtp_read_command(FALSE
))
5035 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by EOF",
5036 smtp_get_connection_info());
5037 smtp_notquit_exit(US
"tls-failed", NULL
, NULL
);
5041 /* It is perhaps arguable as to which exit ACL should be called here,
5042 but as it is probably a situation that almost never arises, it
5043 probably doesn't matter. We choose to call the real QUIT ACL, which in
5044 some sense is perhaps "right". */
5048 if (acl_smtp_quit
!= NULL
)
5050 rc
= acl_check(ACL_WHERE_QUIT
, NULL
, acl_smtp_quit
, &user_msg
,
5053 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for QUIT returned ERROR: %s",
5056 if (user_msg
== NULL
)
5057 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
5059 smtp_respond(US
"221", 3, TRUE
, user_msg
);
5060 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by QUIT",
5061 smtp_get_connection_info());
5066 smtp_printf("554 Security failure\r\n");
5070 tls_close(TRUE
, TRUE
);
5075 /* The ACL for QUIT is provided for gathering statistical information or
5076 similar; it does not affect the response code, but it can supply a custom
5080 smtp_quit_handler(&user_msg
, &log_msg
);
5086 smtp_rset_handler();
5087 smtp_reset(reset_point
);
5094 smtp_printf("250 OK\r\n");
5098 /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually
5099 used, a check will be done for permitted hosts. Show STARTTLS only if not
5100 already in a TLS session and if it would be advertised in the EHLO
5105 smtp_printf("214-Commands supported:\r\n");
5109 Ustrcat(buffer
, " AUTH");
5111 if (tls_in
.active
< 0 &&
5112 verify_check_host(&tls_advertise_hosts
) != FAIL
)
5113 Ustrcat(buffer
, " STARTTLS");
5115 Ustrcat(buffer
, " HELO EHLO MAIL RCPT DATA BDAT");
5116 Ustrcat(buffer
, " NOOP QUIT RSET HELP");
5117 if (acl_smtp_etrn
!= NULL
) Ustrcat(buffer
, " ETRN");
5118 if (acl_smtp_expn
!= NULL
) Ustrcat(buffer
, " EXPN");
5119 if (acl_smtp_vrfy
!= NULL
) Ustrcat(buffer
, " VRFY");
5120 smtp_printf("214%s\r\n", buffer
);
5126 incomplete_transaction_log(US
"connection lost");
5127 smtp_notquit_exit(US
"connection-lost", US
"421",
5128 US
"%s lost input connection", smtp_active_hostname
);
5130 /* Don't log by default unless in the middle of a message, as some mailers
5131 just drop the call rather than sending QUIT, and it clutters up the logs.
5134 if (sender_address
!= NULL
|| recipients_count
> 0)
5135 log_write(L_lost_incoming_connection
,
5137 "unexpected %s while reading SMTP command from %s%s",
5138 sender_host_unknown
? "EOF" : "disconnection",
5139 host_and_ident(FALSE
), smtp_read_error
);
5141 else log_write(L_smtp_connection
, LOG_MAIN
, "%s lost%s",
5142 smtp_get_connection_info(), smtp_read_error
);
5150 if (sender_address
!= NULL
)
5152 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
5153 US
"ETRN is not permitted inside a transaction");
5157 log_write(L_etrn
, LOG_MAIN
, "ETRN %s received from %s", smtp_cmd_argument
,
5158 host_and_ident(FALSE
));
5160 if ((rc
= acl_check(ACL_WHERE_ETRN
, NULL
, acl_smtp_etrn
,
5161 &user_msg
, &log_msg
)) != OK
)
5163 done
= smtp_handle_acl_fail(ACL_WHERE_ETRN
, rc
, user_msg
, log_msg
);
5167 /* Compute the serialization key for this command. */
5169 etrn_serialize_key
= string_sprintf("etrn-%s\n", smtp_cmd_data
);
5171 /* If a command has been specified for running as a result of ETRN, we
5172 permit any argument to ETRN. If not, only the # standard form is permitted,
5173 since that is strictly the only kind of ETRN that can be implemented
5174 according to the RFC. */
5176 if (smtp_etrn_command
!= NULL
)
5180 etrn_command
= smtp_etrn_command
;
5181 deliver_domain
= smtp_cmd_data
;
5182 rc
= transport_set_up_command(&argv
, smtp_etrn_command
, TRUE
, 0, NULL
,
5183 US
"ETRN processing", &error
);
5184 deliver_domain
= NULL
;
5187 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to set up ETRN command: %s",
5189 smtp_printf("458 Internal failure\r\n");
5194 /* Else set up to call Exim with the -R option. */
5198 if (*smtp_cmd_data
++ != '#')
5200 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
5201 US
"argument must begin with #");
5204 etrn_command
= US
"exim -R";
5205 argv
= CUSS
child_exec_exim(CEE_RETURN_ARGV
, TRUE
, NULL
, TRUE
,
5206 *queue_name
? 4 : 2,
5207 US
"-R", smtp_cmd_data
,
5208 US
"-MCG", queue_name
);
5211 /* If we are host-testing, don't actually do anything. */
5217 debug_printf("ETRN command is: %s\n", etrn_command
);
5218 debug_printf("ETRN command execution skipped\n");
5220 if (user_msg
== NULL
) smtp_printf("250 OK\r\n");
5221 else smtp_user_msg(US
"250", user_msg
);
5226 /* If ETRN queue runs are to be serialized, check the database to
5227 ensure one isn't already running. */
5229 if (smtp_etrn_serialize
&& !enq_start(etrn_serialize_key
, 1))
5231 smtp_printf("458 Already processing %s\r\n", smtp_cmd_data
);
5235 /* Fork a child process and run the command. We don't want to have to
5236 wait for the process at any point, so set SIGCHLD to SIG_IGN before
5237 forking. It should be set that way anyway for external incoming SMTP,
5238 but we save and restore to be tidy. If serialization is required, we
5239 actually run the command in yet another process, so we can wait for it
5240 to complete and then remove the serialization lock. */
5242 oldsignal
= signal(SIGCHLD
, SIG_IGN
);
5244 if ((pid
= fork()) == 0)
5246 smtp_input
= FALSE
; /* This process is not associated with the */
5247 (void)fclose(smtp_in
); /* SMTP call any more. */
5248 (void)fclose(smtp_out
);
5250 signal(SIGCHLD
, SIG_DFL
); /* Want to catch child */
5252 /* If not serializing, do the exec right away. Otherwise, fork down
5253 into another process. */
5255 if (!smtp_etrn_serialize
|| (pid
= fork()) == 0)
5257 DEBUG(D_exec
) debug_print_argv(argv
);
5258 exim_nullstd(); /* Ensure std{in,out,err} exist */
5259 execv(CS argv
[0], (char *const *)argv
);
5260 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "exec of \"%s\" (ETRN) failed: %s",
5261 etrn_command
, strerror(errno
));
5262 _exit(EXIT_FAILURE
); /* paranoia */
5265 /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That
5266 is, we are in the first subprocess, after forking again. All we can do
5267 for a failing fork is to log it. Otherwise, wait for the 2nd process to
5268 complete, before removing the serialization. */
5271 log_write(0, LOG_MAIN
|LOG_PANIC
, "2nd fork for serialized ETRN "
5272 "failed: %s", strerror(errno
));
5276 DEBUG(D_any
) debug_printf("waiting for serialized ETRN process %d\n",
5278 (void)wait(&status
);
5279 DEBUG(D_any
) debug_printf("serialized ETRN process %d ended\n",
5283 enq_end(etrn_serialize_key
);
5284 _exit(EXIT_SUCCESS
);
5287 /* Back in the top level SMTP process. Check that we started a subprocess
5288 and restore the signal state. */
5292 log_write(0, LOG_MAIN
|LOG_PANIC
, "fork of process for ETRN failed: %s",
5294 smtp_printf("458 Unable to fork process\r\n");
5295 if (smtp_etrn_serialize
) enq_end(etrn_serialize_key
);
5299 if (user_msg
== NULL
) smtp_printf("250 OK\r\n");
5300 else smtp_user_msg(US
"250", user_msg
);
5303 signal(SIGCHLD
, oldsignal
);
5308 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
5309 US
"unexpected argument data");
5313 /* This currently happens only for NULLs, but could be extended. */
5316 done
= synprot_error(L_smtp_syntax_error
, 0, NULL
, /* Just logs */
5317 US
"NULL character(s) present (shown as '?')");
5318 smtp_printf("501 NULL characters are not allowed in SMTP commands\r\n");
5324 if (smtp_inend
>= smtp_inbuffer
+ in_buffer_size
)
5325 smtp_inend
= smtp_inbuffer
+ in_buffer_size
- 1;
5326 c
= smtp_inend
- smtp_inptr
;
5327 if (c
> 150) c
= 150;
5329 incomplete_transaction_log(US
"sync failure");
5330 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP protocol synchronization error "
5331 "(next input sent too soon: pipelining was%s advertised): "
5332 "rejected \"%s\" %s next input=\"%s\"",
5333 pipelining_advertised
? "" : " not",
5334 smtp_cmd_buffer
, host_and_ident(TRUE
),
5335 string_printing(smtp_inptr
));
5336 smtp_notquit_exit(US
"synchronization-error", US
"554",
5337 US
"SMTP synchronization error");
5338 done
= 1; /* Pretend eof - drops connection */
5342 case TOO_MANY_NONMAIL_CMD
:
5343 s
= smtp_cmd_buffer
;
5344 while (*s
!= 0 && !isspace(*s
)) s
++;
5345 incomplete_transaction_log(US
"too many non-mail commands");
5346 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
5347 "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE
),
5348 (int)(s
- smtp_cmd_buffer
), smtp_cmd_buffer
);
5349 smtp_notquit_exit(US
"bad-commands", US
"554", US
"Too many nonmail commands");
5350 done
= 1; /* Pretend eof - drops connection */
5353 #ifdef SUPPORT_PROXY
5354 case PROXY_FAIL_IGNORE_CMD
:
5355 smtp_printf("503 Command refused, required Proxy negotiation failed\r\n");
5360 if (unknown_command_count
++ >= smtp_max_unknown_commands
)
5362 log_write(L_smtp_syntax_error
, LOG_MAIN
,
5363 "SMTP syntax error in \"%s\" %s %s",
5364 string_printing(smtp_cmd_buffer
), host_and_ident(TRUE
),
5365 US
"unrecognized command");
5366 incomplete_transaction_log(US
"unrecognized command");
5367 smtp_notquit_exit(US
"bad-commands", US
"500",
5368 US
"Too many unrecognized commands");
5370 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
5371 "unrecognized commands (last was \"%s\")", host_and_ident(FALSE
),
5372 string_printing(smtp_cmd_buffer
));
5375 done
= synprot_error(L_smtp_syntax_error
, 500, NULL
,
5376 US
"unrecognized command");
5380 /* This label is used by goto's inside loops that want to break out to
5381 the end of the command-processing loop. */
5384 last_was_rej_mail
= was_rej_mail
; /* Remember some last commands for */
5385 last_was_rcpt
= was_rcpt
; /* protocol error handling */
5389 return done
- 2; /* Convert yield values */
5394 /* End of smtp_in.c */