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
)
328 if (!smtp_out
) return EOF
;
330 if (smtp_receive_timeout
> 0) alarm(smtp_receive_timeout
);
331 rc
= read(fileno(smtp_in
), smtp_inbuffer
, in_buffer_size
);
336 /* Must put the error text in fixed store, because this might be during
337 header reading, where it releases unused store above the header. */
340 smtp_had_error
= save_errno
;
341 smtp_read_error
= string_copy_malloc(
342 string_sprintf(" (error: %s)", strerror(save_errno
)));
344 else smtp_had_eof
= 1;
348 dkim_exim_verify_feed(smtp_inbuffer
, rc
);
350 smtp_inend
= smtp_inbuffer
+ rc
;
351 smtp_inptr
= smtp_inbuffer
;
353 return *smtp_inptr
++;
360 int n
= smtp_inend
- smtp_inptr
;
362 dkim_exim_verify_feed(smtp_inptr
, n
);
367 /* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the
368 previous BDAT chunk and getting new ones when we run out. Uses the
369 underlying smtp_getc or tls_getc both for that and for getting the
370 (buffered) data byte. EOD signals (an expected) no further data.
371 ERR signals a protocol error, and EOF a closed input stream.
373 Called from read_bdat_smtp() in receive.c for the message body, but also
374 by the headers read loop in receive_msg(); manipulates chunking_state
375 to handle the BDAT command/response.
376 Placed here due to the correlation with the above smtp_getc(), which it wraps,
377 and also by the need to do smtp command/response handling.
380 Returns: the next character or ERR, EOD or EOF
386 uschar
* user_msg
= NULL
;
391 if (chunking_data_left
-- > 0)
392 return lwr_receive_getc();
394 receive_getc
= lwr_receive_getc
;
395 receive_ungetc
= lwr_receive_ungetc
;
397 /* If not the last, ack the received chunk. The last response is delayed
398 until after the data ACL decides on it */
400 if (chunking_state
== CHUNKING_LAST
)
403 dkim_exim_verify_feed(NULL
, 0); /* notify EOD */
408 chunking_state
= CHUNKING_OFFERED
;
409 smtp_printf("250 %u byte chunk received\r\n", chunking_datasize
);
411 /* Expect another BDAT cmd from input. RFC 3030 says nothing about
412 QUIT, RSET or NOOP but handling them seems obvious */
415 switch(smtp_read_command(TRUE
))
418 (void) synprot_error(L_smtp_protocol_error
, 503, NULL
,
419 US
"only BDAT permissible after non-LAST BDAT");
422 switch(smtp_read_command(TRUE
))
424 case QUIT_CMD
: smtp_quit_handler(&user_msg
, &log_msg
); /*FALLTHROUGH */
425 case EOF_CMD
: return EOF
;
426 case RSET_CMD
: smtp_rset_handler(); return ERR
;
427 default: if (synprot_error(L_smtp_protocol_error
, 503, NULL
,
428 US
"only RSET accepted now") > 0)
430 goto repeat_until_rset
;
434 smtp_quit_handler(&user_msg
, &log_msg
);
445 smtp_printf("250 OK\r\n");
452 if (sscanf(CS smtp_cmd_data
, "%u %n", &chunking_datasize
, &n
) < 1)
454 (void) synprot_error(L_smtp_protocol_error
, 501, NULL
,
455 US
"missing size for BDAT command");
458 chunking_state
= strcmpic(smtp_cmd_data
+n
, US
"LAST") == 0
459 ? CHUNKING_LAST
: CHUNKING_ACTIVE
;
460 chunking_data_left
= chunking_datasize
;
462 if (chunking_datasize
== 0)
463 if (chunking_state
== CHUNKING_LAST
)
467 (void) synprot_error(L_smtp_protocol_error
, 504, NULL
,
468 US
"zero size for BDAT command");
469 goto repeat_until_rset
;
472 receive_getc
= bdat_getc
;
473 receive_ungetc
= bdat_ungetc
;
474 break; /* to top of main loop */
481 bdat_flush_data(void)
483 while (chunking_data_left
-- > 0)
484 if (lwr_receive_getc() < 0)
487 receive_getc
= lwr_receive_getc
;
488 receive_ungetc
= lwr_receive_ungetc
;
490 if (chunking_state
!= CHUNKING_LAST
)
491 chunking_state
= CHUNKING_OFFERED
;
497 /*************************************************
498 * SMTP version of ungetc() *
499 *************************************************/
501 /* Puts a character back in the input buffer. Only ever
507 Returns: the character
521 chunking_data_left
++;
522 return lwr_receive_ungetc(ch
);
527 /*************************************************
528 * SMTP version of feof() *
529 *************************************************/
531 /* Tests for a previous EOF
534 Returns: non-zero if the eof flag is set
546 /*************************************************
547 * SMTP version of ferror() *
548 *************************************************/
550 /* Tests for a previous read error, and returns with errno
551 restored to what it was when the error was detected.
554 Returns: non-zero if the error flag is set
560 errno
= smtp_had_error
;
561 return smtp_had_error
;
566 /*************************************************
567 * Test for characters in the SMTP buffer *
568 *************************************************/
570 /* Used at the end of a message
579 return smtp_inptr
< smtp_inend
;
584 /*************************************************
585 * Write formatted string to SMTP channel *
586 *************************************************/
588 /* This is a separate function so that we don't have to repeat everything for
589 TLS support or debugging. It is global so that the daemon and the
590 authentication functions can use it. It does not return any error indication,
591 because major problems such as dropped connections won't show up till an output
592 flush for non-TLS connections. The smtp_fflush() function is available for
593 checking that: for convenience, TLS output errors are remembered here so that
594 they are also picked up later by smtp_fflush().
598 ... optional arguments
604 smtp_printf(const char *format
, ...)
608 va_start(ap
, format
);
609 smtp_vprintf(format
, ap
);
613 /* This is split off so that verify.c:respond_printf() can, in effect, call
614 smtp_printf(), bearing in mind that in C a vararg function can't directly
615 call another vararg function, only a function which accepts a va_list. */
618 smtp_vprintf(const char *format
, va_list ap
)
622 yield
= string_vformat(big_buffer
, big_buffer_size
, format
, ap
);
626 void *reset_point
= store_get(0);
627 uschar
*msg_copy
, *cr
, *end
;
628 msg_copy
= string_copy(big_buffer
);
629 end
= msg_copy
+ Ustrlen(msg_copy
);
630 while ((cr
= Ustrchr(msg_copy
, '\r')) != NULL
) /* lose CRs */
631 memmove(cr
, cr
+ 1, (end
--) - cr
);
632 debug_printf("SMTP>> %s", msg_copy
);
633 store_reset(reset_point
);
638 log_write(0, LOG_MAIN
|LOG_PANIC
, "string too large in smtp_printf()");
639 smtp_closedown(US
"Unexpected error");
640 exim_exit(EXIT_FAILURE
);
643 /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
644 have had the same. Note: this code is also present in smtp_respond(). It would
645 be tidier to have it only in one place, but when it was added, it was easier to
646 do it that way, so as not to have to mess with the code for the RCPT command,
647 which sometimes uses smtp_printf() and sometimes smtp_respond(). */
649 if (rcpt_in_progress
)
651 if (rcpt_smtp_response
== NULL
)
652 rcpt_smtp_response
= string_copy(big_buffer
);
653 else if (rcpt_smtp_response_same
&&
654 Ustrcmp(rcpt_smtp_response
, big_buffer
) != 0)
655 rcpt_smtp_response_same
= FALSE
;
656 rcpt_in_progress
= FALSE
;
659 /* Now write the string */
662 if (tls_in
.active
>= 0)
664 if (tls_write(TRUE
, big_buffer
, Ustrlen(big_buffer
)) < 0)
665 smtp_write_error
= -1;
670 if (fprintf(smtp_out
, "%s", big_buffer
) < 0) smtp_write_error
= -1;
675 /*************************************************
676 * Flush SMTP out and check for error *
677 *************************************************/
679 /* This function isn't currently used within Exim (it detects errors when it
680 tries to read the next SMTP input), but is available for use in local_scan().
681 For non-TLS connections, it flushes the output and checks for errors. For
682 TLS-connections, it checks for a previously-detected TLS write error.
685 Returns: 0 for no error; -1 after an error
691 if (tls_in
.active
< 0 && fflush(smtp_out
) != 0) smtp_write_error
= -1;
692 return smtp_write_error
;
697 /*************************************************
698 * SMTP command read timeout *
699 *************************************************/
701 /* Signal handler for timing out incoming SMTP commands. This attempts to
704 Argument: signal number (SIGALRM)
709 command_timeout_handler(int sig
)
711 sig
= sig
; /* Keep picky compilers happy */
712 log_write(L_lost_incoming_connection
,
713 LOG_MAIN
, "SMTP command timeout on%s connection from %s",
714 (tls_in
.active
>= 0)? " TLS" : "",
715 host_and_ident(FALSE
));
716 if (smtp_batched_input
)
717 moan_smtp_batch(NULL
, "421 SMTP command timeout"); /* Does not return */
718 smtp_notquit_exit(US
"command-timeout", US
"421",
719 US
"%s: SMTP command timeout - closing connection", smtp_active_hostname
);
720 exim_exit(EXIT_FAILURE
);
725 /*************************************************
727 *************************************************/
729 /* Signal handler for handling SIGTERM. Again, try to finish tidily.
731 Argument: signal number (SIGTERM)
736 command_sigterm_handler(int sig
)
738 sig
= sig
; /* Keep picky compilers happy */
739 log_write(0, LOG_MAIN
, "%s closed after SIGTERM", smtp_get_connection_info());
740 if (smtp_batched_input
)
741 moan_smtp_batch(NULL
, "421 SIGTERM received"); /* Does not return */
742 smtp_notquit_exit(US
"signal-exit", US
"421",
743 US
"%s: Service not available - closing connection", smtp_active_hostname
);
744 exim_exit(EXIT_FAILURE
);
751 /*************************************************
752 * Restore socket timeout to previous value *
753 *************************************************/
754 /* If the previous value was successfully retrieved, restore
755 it before returning control to the non-proxy routines
757 Arguments: fd - File descriptor for input
758 get_ok - Successfully retrieved previous values
759 tvtmp - Time struct with previous values
760 vslen - Length of time struct
764 restore_socket_timeout(int fd
, int get_ok
, struct timeval tvtmp
, socklen_t vslen
)
767 setsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tvtmp
, vslen
);
770 /*************************************************
771 * Check if host is required proxy host *
772 *************************************************/
773 /* The function determines if inbound host will be a regular smtp host
774 or if it is configured that it must use Proxy Protocol.
781 check_proxy_protocol_host()
784 /* Cannot configure local connection as a proxy inbound */
785 if (sender_host_address
== NULL
) return proxy_session
;
787 rc
= verify_check_this_host(CUSS
&hosts_proxy
, NULL
, NULL
,
788 sender_host_address
, NULL
);
792 debug_printf("Detected proxy protocol configured host\n");
793 proxy_session
= TRUE
;
795 return proxy_session
;
799 /*************************************************
800 * Setup host for proxy protocol *
801 *************************************************/
802 /* The function configures the connection based on a header from the
803 inbound host to use Proxy Protocol. The specification is very exact
804 so exit with an error if do not find the exact required pieces. This
805 includes an incorrect number of spaces separating args.
812 setup_proxy_protocol_host()
824 struct { /* TCP/UDP over IPv4, len = 12 */
830 struct { /* TCP/UDP over IPv6, len = 36 */
831 uint8_t src_addr
[16];
832 uint8_t dst_addr
[16];
836 struct { /* AF_UNIX sockets, len = 216 */
837 uschar src_addr
[108];
838 uschar dst_addr
[108];
844 /* Temp variables used in PPv2 address:port parsing */
846 char tmpip
[INET_ADDRSTRLEN
];
847 struct sockaddr_in tmpaddr
;
848 char tmpip6
[INET6_ADDRSTRLEN
];
849 struct sockaddr_in6 tmpaddr6
;
853 const char v2sig
[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
854 uschar
*iptype
; /* To display debug info */
857 struct timeval tvtmp
;
859 vslen
= sizeof(struct timeval
);
861 fd
= fileno(smtp_in
);
863 /* Save current socket timeout values */
864 get_ok
= getsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tvtmp
,
867 /* Proxy Protocol host must send header within a short time
868 (default 3 seconds) or it's considered invalid */
869 tv
.tv_sec
= PROXY_NEGOTIATION_TIMEOUT_SEC
;
870 tv
.tv_usec
= PROXY_NEGOTIATION_TIMEOUT_USEC
;
871 setsockopt(fd
, SOL_SOCKET
, SO_RCVTIMEO
, (char *)&tv
,
872 sizeof(struct timeval
));
876 /* The inbound host was declared to be a Proxy Protocol host, so
877 don't do a PEEK into the data, actually slurp it up. */
878 ret
= recv(fd
, &hdr
, sizeof(hdr
), 0);
880 while (ret
== -1 && errno
== EINTR
);
884 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
885 return (errno
== EAGAIN
) ? 0 : ERRNO_PROXYFAIL
;
889 memcmp(&hdr
.v2
, v2sig
, 12) == 0)
893 /* May 2014: haproxy combined the version and command into one byte to
894 allow two full bytes for the length field in order to proxy SSL
895 connections. SSL Proxy is not supported in this version of Exim, but
896 must still seperate values here. */
897 ver
= (hdr
.v2
.ver_cmd
& 0xf0) >> 4;
898 cmd
= (hdr
.v2
.ver_cmd
& 0x0f);
902 DEBUG(D_receive
) debug_printf("Invalid Proxy Protocol version: %d\n", ver
);
905 DEBUG(D_receive
) debug_printf("Detected PROXYv2 header\n");
906 /* The v2 header will always be 16 bytes per the spec. */
907 size
= 16 + hdr
.v2
.len
;
910 DEBUG(D_receive
) debug_printf("Truncated or too large PROXYv2 header (%d/%d)\n",
916 case 0x01: /* PROXY command */
919 case 0x11: /* TCPv4 address type */
921 tmpaddr
.sin_addr
.s_addr
= hdr
.v2
.addr
.ip4
.src_addr
;
922 inet_ntop(AF_INET
, &(tmpaddr
.sin_addr
), (char *)&tmpip
, sizeof(tmpip
));
923 if (!string_is_ip_address(US tmpip
,NULL
))
925 DEBUG(D_receive
) debug_printf("Invalid %s source IP\n", iptype
);
926 return ERRNO_PROXYFAIL
;
928 proxy_local_address
= sender_host_address
;
929 sender_host_address
= string_copy(US tmpip
);
930 tmpport
= ntohs(hdr
.v2
.addr
.ip4
.src_port
);
931 proxy_local_port
= sender_host_port
;
932 sender_host_port
= tmpport
;
933 /* Save dest ip/port */
934 tmpaddr
.sin_addr
.s_addr
= hdr
.v2
.addr
.ip4
.dst_addr
;
935 inet_ntop(AF_INET
, &(tmpaddr
.sin_addr
), (char *)&tmpip
, sizeof(tmpip
));
936 if (!string_is_ip_address(US tmpip
,NULL
))
938 DEBUG(D_receive
) debug_printf("Invalid %s dest port\n", iptype
);
939 return ERRNO_PROXYFAIL
;
941 proxy_external_address
= string_copy(US tmpip
);
942 tmpport
= ntohs(hdr
.v2
.addr
.ip4
.dst_port
);
943 proxy_external_port
= tmpport
;
945 case 0x21: /* TCPv6 address type */
947 memmove(tmpaddr6
.sin6_addr
.s6_addr
, hdr
.v2
.addr
.ip6
.src_addr
, 16);
948 inet_ntop(AF_INET6
, &(tmpaddr6
.sin6_addr
), (char *)&tmpip6
, sizeof(tmpip6
));
949 if (!string_is_ip_address(US tmpip6
,NULL
))
951 DEBUG(D_receive
) debug_printf("Invalid %s source IP\n", iptype
);
952 return ERRNO_PROXYFAIL
;
954 proxy_local_address
= sender_host_address
;
955 sender_host_address
= string_copy(US tmpip6
);
956 tmpport
= ntohs(hdr
.v2
.addr
.ip6
.src_port
);
957 proxy_local_port
= sender_host_port
;
958 sender_host_port
= tmpport
;
959 /* Save dest ip/port */
960 memmove(tmpaddr6
.sin6_addr
.s6_addr
, hdr
.v2
.addr
.ip6
.dst_addr
, 16);
961 inet_ntop(AF_INET6
, &(tmpaddr6
.sin6_addr
), (char *)&tmpip6
, sizeof(tmpip6
));
962 if (!string_is_ip_address(US tmpip6
,NULL
))
964 DEBUG(D_receive
) debug_printf("Invalid %s dest port\n", iptype
);
965 return ERRNO_PROXYFAIL
;
967 proxy_external_address
= string_copy(US tmpip6
);
968 tmpport
= ntohs(hdr
.v2
.addr
.ip6
.dst_port
);
969 proxy_external_port
= tmpport
;
973 debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n",
977 /* Unsupported protocol, keep local connection address */
979 case 0x00: /* LOCAL command */
980 /* Keep local connection address for LOCAL */
984 debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd
);
989 memcmp(hdr
.v1
.line
, "PROXY", 5) == 0)
991 uschar
*p
= string_copy(hdr
.v1
.line
);
992 uschar
*end
= memchr(p
, '\r', ret
- 1);
993 uschar
*sp
; /* Utility variables follow */
997 if (!end
|| end
[1] != '\n')
999 DEBUG(D_receive
) debug_printf("Partial or invalid PROXY header\n");
1002 *end
= '\0'; /* Terminate the string */
1003 size
= end
+ 2 - hdr
.v1
.line
; /* Skip header + CRLF */
1004 DEBUG(D_receive
) debug_printf("Detected PROXYv1 header\n");
1005 /* Step through the string looking for the required fields. Ensure
1006 strict adherance to required formatting, exit for any error. */
1008 if (!isspace(*(p
++)))
1010 DEBUG(D_receive
) debug_printf("Missing space after PROXY command\n");
1013 if (!Ustrncmp(p
, CCS
"TCP4", 4))
1015 else if (!Ustrncmp(p
,CCS
"TCP6", 4))
1017 else if (!Ustrncmp(p
,CCS
"UNKNOWN", 7))
1019 iptype
= US
"Unknown";
1024 DEBUG(D_receive
) debug_printf("Invalid TCP type\n");
1028 p
+= Ustrlen(iptype
);
1029 if (!isspace(*(p
++)))
1031 DEBUG(D_receive
) debug_printf("Missing space after TCP4/6 command\n");
1034 /* Find the end of the arg */
1035 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1038 debug_printf("Did not find proxied src %s\n", iptype
);
1042 if(!string_is_ip_address(p
,NULL
))
1045 debug_printf("Proxied src arg is not an %s address\n", iptype
);
1048 proxy_local_address
= sender_host_address
;
1049 sender_host_address
= p
;
1051 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1054 debug_printf("Did not find proxy dest %s\n", iptype
);
1058 if(!string_is_ip_address(p
,NULL
))
1061 debug_printf("Proxy dest arg is not an %s address\n", iptype
);
1064 proxy_external_address
= p
;
1066 if ((sp
= Ustrchr(p
, ' ')) == NULL
)
1068 DEBUG(D_receive
) debug_printf("Did not find proxied src port\n");
1072 tmp_port
= strtol(CCS p
,&endc
,10);
1073 if (*endc
|| tmp_port
== 0)
1076 debug_printf("Proxied src port '%s' not an integer\n", p
);
1079 proxy_local_port
= sender_host_port
;
1080 sender_host_port
= tmp_port
;
1082 if ((sp
= Ustrchr(p
, '\0')) == NULL
)
1084 DEBUG(D_receive
) debug_printf("Did not find proxy dest port\n");
1087 tmp_port
= strtol(CCS p
,&endc
,10);
1088 if (*endc
|| tmp_port
== 0)
1091 debug_printf("Proxy dest port '%s' not an integer\n", p
);
1094 proxy_external_port
= tmp_port
;
1095 /* Already checked for /r /n above. Good V1 header received. */
1100 /* Wrong protocol */
1101 DEBUG(D_receive
) debug_printf("Invalid proxy protocol version negotiation\n");
1106 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
1107 /* Don't flush any potential buffer contents. Any input should cause a
1108 synchronization failure */
1112 restore_socket_timeout(fd
, get_ok
, tvtmp
, vslen
);
1114 debug_printf("Valid %s sender from Proxy Protocol header\n", iptype
);
1115 return proxy_session
;
1119 /*************************************************
1120 * Read one command line *
1121 *************************************************/
1123 /* Strictly, SMTP commands coming over the net are supposed to end with CRLF.
1124 There are sites that don't do this, and in any case internal SMTP probably
1125 should check only for LF. Consequently, we check here for LF only. The line
1126 ends up with [CR]LF removed from its end. If we get an overlong line, treat as
1127 an unknown command. The command is read into the global smtp_cmd_buffer so that
1128 it is available via $smtp_command.
1130 The character reading routine sets up a timeout for each block actually read
1131 from the input (which may contain more than one command). We set up a special
1132 signal handler that closes down the session on a timeout. Control does not
1133 return when it runs.
1136 check_sync if TRUE, check synchronization rules if global option is TRUE
1138 Returns: a code identifying the command (enumerated above)
1142 smtp_read_command(BOOL check_sync
)
1147 BOOL hadnull
= FALSE
;
1149 os_non_restarting_signal(SIGALRM
, command_timeout_handler
);
1151 while ((c
= (receive_getc
)()) != '\n' && c
!= EOF
)
1153 if (ptr
>= smtp_cmd_buffer_size
)
1155 os_non_restarting_signal(SIGALRM
, sigalrm_handler
);
1163 smtp_cmd_buffer
[ptr
++] = c
;
1166 receive_linecount
++; /* For BSMTP errors */
1167 os_non_restarting_signal(SIGALRM
, sigalrm_handler
);
1169 /* If hit end of file, return pseudo EOF command. Whether we have a
1170 part-line already read doesn't matter, since this is an error state. */
1172 if (c
== EOF
) return EOF_CMD
;
1174 /* Remove any CR and white space at the end of the line, and terminate the
1177 while (ptr
> 0 && isspace(smtp_cmd_buffer
[ptr
-1])) ptr
--;
1178 smtp_cmd_buffer
[ptr
] = 0;
1180 DEBUG(D_receive
) debug_printf("SMTP<< %s\n", smtp_cmd_buffer
);
1182 /* NULLs are not allowed in SMTP commands */
1184 if (hadnull
) return BADCHAR_CMD
;
1186 /* Scan command list and return identity, having set the data pointer
1187 to the start of the actual data characters. Check for SMTP synchronization
1190 for (p
= cmd_list
; p
< cmd_list_end
; p
++)
1192 #ifdef SUPPORT_PROXY
1193 /* Only allow QUIT command if Proxy Protocol parsing failed */
1194 if (proxy_session
&& proxy_session_failed
)
1196 if (p
->cmd
!= QUIT_CMD
)
1201 && strncmpic(smtp_cmd_buffer
, US p
->name
, p
->len
) == 0
1202 && ( smtp_cmd_buffer
[p
->len
-1] == ':' /* "mail from:" or "rcpt to:" */
1203 || smtp_cmd_buffer
[p
->len
] == 0
1204 || smtp_cmd_buffer
[p
->len
] == ' '
1207 if (smtp_inptr
< smtp_inend
&& /* Outstanding input */
1208 p
->cmd
< sync_cmd_limit
&& /* Command should sync */
1209 check_sync
&& /* Local flag set */
1210 smtp_enforce_sync
&& /* Global flag set */
1211 sender_host_address
!= NULL
&& /* Not local input */
1212 !sender_host_notsocket
) /* Really is a socket */
1215 /* The variables $smtp_command and $smtp_command_argument point into the
1216 unmodified input buffer. A copy of the latter is taken for actual
1217 processing, so that it can be chopped up into separate parts if necessary,
1218 for example, when processing a MAIL command options such as SIZE that can
1219 follow the sender address. */
1221 smtp_cmd_argument
= smtp_cmd_buffer
+ p
->len
;
1222 while (isspace(*smtp_cmd_argument
)) smtp_cmd_argument
++;
1223 Ustrcpy(smtp_data_buffer
, smtp_cmd_argument
);
1224 smtp_cmd_data
= smtp_data_buffer
;
1226 /* Count non-mail commands from those hosts that are controlled in this
1227 way. The default is all hosts. We don't waste effort checking the list
1228 until we get a non-mail command, but then cache the result to save checking
1229 again. If there's a DEFER while checking the host, assume it's in the list.
1231 Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the
1232 start of each incoming message by fiddling with the value in the table. */
1234 if (!p
->is_mail_cmd
)
1236 if (count_nonmail
== TRUE_UNSET
) count_nonmail
=
1237 verify_check_host(&smtp_accept_max_nonmail_hosts
) != FAIL
;
1238 if (count_nonmail
&& ++nonmail_command_count
> smtp_accept_max_nonmail
)
1239 return TOO_MANY_NONMAIL_CMD
;
1242 /* If there is data for a command that does not expect it, generate the
1245 return (p
->has_arg
|| *smtp_cmd_data
== 0)? p
->cmd
: BADARG_CMD
;
1249 #ifdef SUPPORT_PROXY
1250 /* Only allow QUIT command if Proxy Protocol parsing failed */
1251 if (proxy_session
&& proxy_session_failed
)
1252 return PROXY_FAIL_IGNORE_CMD
;
1255 /* Enforce synchronization for unknown commands */
1257 if (smtp_inptr
< smtp_inend
&& /* Outstanding input */
1258 check_sync
&& /* Local flag set */
1259 smtp_enforce_sync
&& /* Global flag set */
1260 sender_host_address
!= NULL
&& /* Not local input */
1261 !sender_host_notsocket
) /* Really is a socket */
1269 /*************************************************
1270 * Recheck synchronization *
1271 *************************************************/
1273 /* Synchronization checks can never be perfect because a packet may be on its
1274 way but not arrived when the check is done. Such checks can in any case only be
1275 done when TLS is not in use. Normally, the checks happen when commands are
1276 read: Exim ensures that there is no more input in the input buffer. In normal
1277 cases, the response to the command will be fast, and there is no further check.
1279 However, for some commands an ACL is run, and that can include delays. In those
1280 cases, it is useful to do another check on the input just before sending the
1281 response. This also applies at the start of a connection. This function does
1282 that check by means of the select() function, as long as the facility is not
1283 disabled or inappropriate. A failure of select() is ignored.
1285 When there is unwanted input, we read it so that it appears in the log of the
1289 Returns: TRUE if all is well; FALSE if there is input pending
1297 struct timeval tzero
;
1299 if (!smtp_enforce_sync
|| sender_host_address
== NULL
||
1300 sender_host_notsocket
|| tls_in
.active
>= 0)
1303 fd
= fileno(smtp_in
);
1308 rc
= select(fd
+ 1, (SELECT_ARG2_TYPE
*)&fds
, NULL
, NULL
, &tzero
);
1310 if (rc
<= 0) return TRUE
; /* Not ready to read */
1312 if (rc
< 0) return TRUE
; /* End of file or error */
1315 rc
= smtp_inend
- smtp_inptr
;
1316 if (rc
> 150) rc
= 150;
1323 /*************************************************
1324 * Forced closedown of call *
1325 *************************************************/
1327 /* This function is called from log.c when Exim is dying because of a serious
1328 disaster, and also from some other places. If an incoming non-batched SMTP
1329 channel is open, it swallows the rest of the incoming message if in the DATA
1330 phase, sends the reply string, and gives an error to all subsequent commands
1331 except QUIT. The existence of an SMTP call is detected by the non-NULLness of
1335 message SMTP reply string to send, excluding the code
1341 smtp_closedown(uschar
*message
)
1343 if (smtp_in
== NULL
|| smtp_batched_input
) return;
1344 receive_swallow_smtp();
1345 smtp_printf("421 %s\r\n", message
);
1347 for (;;) switch(smtp_read_command(FALSE
))
1353 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
1358 smtp_printf("250 Reset OK\r\n");
1362 smtp_printf("421 %s\r\n", message
);
1370 /*************************************************
1371 * Set up connection info for logging *
1372 *************************************************/
1374 /* This function is called when logging information about an SMTP connection.
1375 It sets up appropriate source information, depending on the type of connection.
1376 If sender_fullhost is NULL, we are at a very early stage of the connection;
1377 just use the IP address.
1380 Returns: a string describing the connection
1384 smtp_get_connection_info(void)
1386 uschar
*hostname
= (sender_fullhost
== NULL
)?
1387 sender_host_address
: sender_fullhost
;
1390 return string_sprintf("SMTP connection from %s", hostname
);
1392 if (sender_host_unknown
|| sender_host_notsocket
)
1393 return string_sprintf("SMTP connection from %s", sender_ident
);
1396 return string_sprintf("SMTP connection from %s (via inetd)", hostname
);
1398 if (LOGGING(incoming_interface
) && interface_address
!= NULL
)
1399 return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname
,
1400 interface_address
, interface_port
);
1402 return string_sprintf("SMTP connection from %s", hostname
);
1408 /* Append TLS-related information to a log line
1411 s String under construction: allocated string to extend, or NULL
1412 sizep Pointer to current allocation size (update on return), or NULL
1413 ptrp Pointer to index for new entries in string (update on return), or NULL
1415 Returns: Allocated string or NULL
1418 s_tlslog(uschar
* s
, int * sizep
, int * ptrp
)
1420 int size
= sizep
? *sizep
: 0;
1421 int ptr
= ptrp
? *ptrp
: 0;
1423 if (LOGGING(tls_cipher
) && tls_in
.cipher
!= NULL
)
1424 s
= string_append(s
, &size
, &ptr
, 2, US
" X=", tls_in
.cipher
);
1425 if (LOGGING(tls_certificate_verified
) && tls_in
.cipher
!= NULL
)
1426 s
= string_append(s
, &size
, &ptr
, 2, US
" CV=",
1427 tls_in
.certificate_verified
? "yes":"no");
1428 if (LOGGING(tls_peerdn
) && tls_in
.peerdn
!= NULL
)
1429 s
= string_append(s
, &size
, &ptr
, 3, US
" DN=\"",
1430 string_printing(tls_in
.peerdn
), US
"\"");
1431 if (LOGGING(tls_sni
) && tls_in
.sni
!= NULL
)
1432 s
= string_append(s
, &size
, &ptr
, 3, US
" SNI=\"",
1433 string_printing(tls_in
.sni
), US
"\"");
1438 if (sizep
) *sizep
= size
;
1439 if (ptrp
) *ptrp
= ptr
;
1445 /*************************************************
1446 * Log lack of MAIL if so configured *
1447 *************************************************/
1449 /* This function is called when an SMTP session ends. If the log selector
1450 smtp_no_mail is set, write a log line giving some details of what has happened
1451 in the SMTP session.
1458 smtp_log_no_mail(void)
1463 if (smtp_mailcmd_count
> 0 || !LOGGING(smtp_no_mail
))
1469 if (sender_host_authenticated
!= NULL
)
1471 s
= string_append(s
, &size
, &ptr
, 2, US
" A=", sender_host_authenticated
);
1472 if (authenticated_id
!= NULL
)
1473 s
= string_append(s
, &size
, &ptr
, 2, US
":", authenticated_id
);
1477 s
= s_tlslog(s
, &size
, &ptr
);
1480 sep
= (smtp_connection_had
[SMTP_HBUFF_SIZE
-1] != SCH_NONE
)?
1481 US
" C=..." : US
" C=";
1482 for (i
= smtp_ch_index
; i
< SMTP_HBUFF_SIZE
; i
++)
1484 if (smtp_connection_had
[i
] != SCH_NONE
)
1486 s
= string_append(s
, &size
, &ptr
, 2, sep
,
1487 smtp_names
[smtp_connection_had
[i
]]);
1492 for (i
= 0; i
< smtp_ch_index
; i
++)
1494 s
= string_append(s
, &size
, &ptr
, 2, sep
, smtp_names
[smtp_connection_had
[i
]]);
1498 if (s
!= NULL
) s
[ptr
] = 0; else s
= US
"";
1499 log_write(0, LOG_MAIN
, "no MAIL in SMTP connection from %s D=%s%s",
1500 host_and_ident(FALSE
),
1501 readconf_printtime( (int) ((long)time(NULL
) - (long)smtp_connection_start
)),
1507 /*************************************************
1508 * Check HELO line and set sender_helo_name *
1509 *************************************************/
1511 /* Check the format of a HELO line. The data for HELO/EHLO is supposed to be
1512 the domain name of the sending host, or an ip literal in square brackets. The
1513 arrgument is placed in sender_helo_name, which is in malloc store, because it
1514 must persist over multiple incoming messages. If helo_accept_junk is set, this
1515 host is permitted to send any old junk (needed for some broken hosts).
1516 Otherwise, helo_allow_chars can be used for rogue characters in general
1517 (typically people want to let in underscores).
1520 s the data portion of the line (already past any white space)
1522 Returns: TRUE or FALSE
1526 check_helo(uschar
*s
)
1529 uschar
*end
= s
+ Ustrlen(s
);
1530 BOOL yield
= helo_accept_junk
;
1532 /* Discard any previous helo name */
1534 if (sender_helo_name
!= NULL
)
1536 store_free(sender_helo_name
);
1537 sender_helo_name
= NULL
;
1540 /* Skip tests if junk is permitted. */
1544 /* Allow the new standard form for IPv6 address literals, namely,
1545 [IPv6:....], and because someone is bound to use it, allow an equivalent
1546 IPv4 form. Allow plain addresses as well. */
1553 if (strncmpic(s
, US
"[IPv6:", 6) == 0)
1554 yield
= (string_is_ip_address(s
+6, NULL
) == 6);
1555 else if (strncmpic(s
, US
"[IPv4:", 6) == 0)
1556 yield
= (string_is_ip_address(s
+6, NULL
) == 4);
1558 yield
= (string_is_ip_address(s
+1, NULL
) != 0);
1563 /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars
1564 that have been configured (usually underscore - sigh). */
1571 if (!isalnum(*s
) && *s
!= '.' && *s
!= '-' &&
1572 Ustrchr(helo_allow_chars
, *s
) == NULL
)
1582 /* Save argument if OK */
1584 if (yield
) sender_helo_name
= string_copy_malloc(start
);
1592 /*************************************************
1593 * Extract SMTP command option *
1594 *************************************************/
1596 /* This function picks the next option setting off the end of smtp_cmd_data. It
1597 is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP
1598 things that can appear there.
1601 name point this at the name
1602 value point this at the data string
1604 Returns: TRUE if found an option
1608 extract_option(uschar
**name
, uschar
**value
)
1611 uschar
*v
= smtp_cmd_data
+ Ustrlen(smtp_cmd_data
) - 1;
1612 while (isspace(*v
)) v
--;
1614 while (v
> smtp_cmd_data
&& *v
!= '=' && !isspace(*v
)) v
--;
1619 while(isalpha(n
[-1])) n
--;
1620 /* RFC says SP, but TAB seen in wild and other major MTAs accept it */
1621 if (!isspace(n
[-1])) return FALSE
;
1627 if (v
== smtp_cmd_data
) return FALSE
;
1639 /*************************************************
1640 * Reset for new message *
1641 *************************************************/
1643 /* This function is called whenever the SMTP session is reset from
1644 within either of the setup functions.
1646 Argument: the stacking pool storage reset point
1651 smtp_reset(void *reset_point
)
1653 store_reset(reset_point
);
1654 recipients_list
= NULL
;
1655 rcpt_count
= rcpt_defer_count
= rcpt_fail_count
=
1656 raw_recipients_count
= recipients_count
= recipients_list_max
= 0;
1657 cancel_cutthrough_connection("smtp reset");
1658 message_linecount
= 0;
1660 acl_added_headers
= NULL
;
1661 acl_removed_headers
= NULL
;
1662 queue_only_policy
= FALSE
;
1663 rcpt_smtp_response
= NULL
;
1664 rcpt_smtp_response_same
= TRUE
;
1665 rcpt_in_progress
= FALSE
;
1666 deliver_freeze
= FALSE
; /* Can be set by ACL */
1667 freeze_tell
= freeze_tell_config
; /* Can be set by ACL */
1668 fake_response
= OK
; /* Can be set by ACL */
1669 #ifdef WITH_CONTENT_SCAN
1670 no_mbox_unspool
= FALSE
; /* Can be set by ACL */
1672 submission_mode
= FALSE
; /* Can be set by ACL */
1673 suppress_local_fixups
= suppress_local_fixups_default
; /* Can be set by ACL */
1674 active_local_from_check
= local_from_check
; /* Can be set by ACL */
1675 active_local_sender_retain
= local_sender_retain
; /* Can be set by ACL */
1676 sender_address
= NULL
;
1677 submission_name
= NULL
; /* Can be set by ACL */
1678 raw_sender
= NULL
; /* After SMTP rewrite, before qualifying */
1679 sender_address_unrewritten
= NULL
; /* Set only after verify rewrite */
1680 sender_verified_list
= NULL
; /* No senders verified */
1681 memset(sender_address_cache
, 0, sizeof(sender_address_cache
));
1682 memset(sender_domain_cache
, 0, sizeof(sender_domain_cache
));
1684 authenticated_sender
= NULL
;
1685 #ifdef EXPERIMENTAL_BRIGHTMAIL
1687 bmi_verdicts
= NULL
;
1689 #ifndef DISABLE_DKIM
1690 dkim_signers
= NULL
;
1691 dkim_disable_verify
= FALSE
;
1692 dkim_collect_input
= FALSE
;
1696 #ifndef DISABLE_PRDR
1697 prdr_requested
= FALSE
;
1699 #ifdef EXPERIMENTAL_SPF
1700 spf_header_comment
= NULL
;
1701 spf_received
= NULL
;
1703 spf_smtp_comment
= NULL
;
1706 message_smtputf8
= FALSE
;
1708 body_linecount
= body_zerocount
= 0;
1710 sender_rate
= sender_rate_limit
= sender_rate_period
= NULL
;
1711 ratelimiters_mail
= NULL
; /* Updated by ratelimit ACL condition */
1712 /* Note that ratelimiters_conn persists across resets. */
1714 /* Reset message ACL variables */
1718 /* The message body variables use malloc store. They may be set if this is
1719 not the first message in an SMTP session and the previous message caused them
1720 to be referenced in an ACL. */
1722 if (message_body
!= NULL
)
1724 store_free(message_body
);
1725 message_body
= NULL
;
1728 if (message_body_end
!= NULL
)
1730 store_free(message_body_end
);
1731 message_body_end
= NULL
;
1734 /* Warning log messages are also saved in malloc store. They are saved to avoid
1735 repetition in the same message, but it seems right to repeat them for different
1738 while (acl_warn_logged
!= NULL
)
1740 string_item
*this = acl_warn_logged
;
1741 acl_warn_logged
= acl_warn_logged
->next
;
1750 /*************************************************
1751 * Initialize for incoming batched SMTP message *
1752 *************************************************/
1754 /* This function is called from smtp_setup_msg() in the case when
1755 smtp_batched_input is true. This happens when -bS is used to pass a whole batch
1756 of messages in one file with SMTP commands between them. All errors must be
1757 reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are
1758 relevant. After an error on a sender, or an invalid recipient, the remainder
1759 of the message is skipped. The value of received_protocol is already set.
1762 Returns: > 0 message successfully started (reached DATA)
1763 = 0 QUIT read or end of file reached
1764 < 0 should not occur
1768 smtp_setup_batch_msg(void)
1771 void *reset_point
= store_get(0);
1773 /* Save the line count at the start of each transaction - single commands
1774 like HELO and RSET count as whole transactions. */
1776 bsmtp_transaction_linecount
= receive_linecount
;
1778 if ((receive_feof
)()) return 0; /* Treat EOF as QUIT */
1780 smtp_reset(reset_point
); /* Reset for start of message */
1782 /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
1783 value. The values are 2 larger than the required yield of the function. */
1788 uschar
*recipient
= NULL
;
1789 int start
, end
, sender_domain
, recipient_domain
;
1791 switch(smtp_read_command(FALSE
))
1793 /* The HELO/EHLO commands set sender_address_helo if they have
1794 valid data; otherwise they are ignored, except that they do
1795 a reset of the state. */
1800 check_helo(smtp_cmd_data
);
1804 smtp_reset(reset_point
);
1805 bsmtp_transaction_linecount
= receive_linecount
;
1809 /* The MAIL FROM command requires an address as an operand. All we
1810 do here is to parse it for syntactic correctness. The form "<>" is
1811 a special case which converts into an empty string. The start/end
1812 pointers in the original are not used further for this address, as
1813 it is the canonical extracted address which is all that is kept. */
1816 smtp_mailcmd_count
++; /* Count for no-mail log */
1817 if (sender_address
!= NULL
)
1818 /* The function moan_smtp_batch() does not return. */
1819 moan_smtp_batch(smtp_cmd_buffer
, "503 Sender already given");
1821 if (smtp_cmd_data
[0] == 0)
1822 /* The function moan_smtp_batch() does not return. */
1823 moan_smtp_batch(smtp_cmd_buffer
, "501 MAIL FROM must have an address operand");
1825 /* Reset to start of message */
1827 smtp_reset(reset_point
);
1829 /* Apply SMTP rewrite */
1831 raw_sender
= ((rewrite_existflags
& rewrite_smtp
) != 0)?
1832 rewrite_one(smtp_cmd_data
, rewrite_smtp
|rewrite_smtp_sender
, NULL
, FALSE
,
1833 US
"", global_rewrite_rules
) : smtp_cmd_data
;
1835 /* Extract the address; the TRUE flag allows <> as valid */
1838 parse_extract_address(raw_sender
, &errmess
, &start
, &end
, &sender_domain
,
1841 if (raw_sender
== NULL
)
1842 /* The function moan_smtp_batch() does not return. */
1843 moan_smtp_batch(smtp_cmd_buffer
, "501 %s", errmess
);
1845 sender_address
= string_copy(raw_sender
);
1847 /* Qualify unqualified sender addresses if permitted to do so. */
1849 if (sender_domain
== 0 && sender_address
[0] != 0 && sender_address
[0] != '@')
1851 if (allow_unqualified_sender
)
1853 sender_address
= rewrite_address_qualify(sender_address
, FALSE
);
1854 DEBUG(D_receive
) debug_printf("unqualified address %s accepted "
1855 "and rewritten\n", raw_sender
);
1857 /* The function moan_smtp_batch() does not return. */
1858 else moan_smtp_batch(smtp_cmd_buffer
, "501 sender address must contain "
1864 /* The RCPT TO command requires an address as an operand. All we do
1865 here is to parse it for syntactic correctness. There may be any number
1866 of RCPT TO commands, specifying multiple senders. We build them all into
1867 a data structure that is in argc/argv format. The start/end values
1868 given by parse_extract_address are not used, as we keep only the
1869 extracted address. */
1872 if (sender_address
== NULL
)
1873 /* The function moan_smtp_batch() does not return. */
1874 moan_smtp_batch(smtp_cmd_buffer
, "503 No sender yet given");
1876 if (smtp_cmd_data
[0] == 0)
1877 /* The function moan_smtp_batch() does not return. */
1878 moan_smtp_batch(smtp_cmd_buffer
, "501 RCPT TO must have an address operand");
1880 /* Check maximum number allowed */
1882 if (recipients_max
> 0 && recipients_count
+ 1 > recipients_max
)
1883 /* The function moan_smtp_batch() does not return. */
1884 moan_smtp_batch(smtp_cmd_buffer
, "%s too many recipients",
1885 recipients_max_reject
? "552": "452");
1887 /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a
1888 recipient address */
1890 recipient
= rewrite_existflags
& rewrite_smtp
1891 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
1892 global_rewrite_rules
)
1895 recipient
= parse_extract_address(recipient
, &errmess
, &start
, &end
,
1896 &recipient_domain
, FALSE
);
1899 /* The function moan_smtp_batch() does not return. */
1900 moan_smtp_batch(smtp_cmd_buffer
, "501 %s", errmess
);
1902 /* If the recipient address is unqualified, qualify it if permitted. Then
1903 add it to the list of recipients. */
1905 if (recipient_domain
== 0)
1907 if (allow_unqualified_recipient
)
1909 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
1911 recipient
= rewrite_address_qualify(recipient
, TRUE
);
1913 /* The function moan_smtp_batch() does not return. */
1914 else moan_smtp_batch(smtp_cmd_buffer
, "501 recipient address must contain "
1917 receive_add_recipient(recipient
, -1);
1921 /* The DATA command is legal only if it follows successful MAIL FROM
1922 and RCPT TO commands. This function is complete when a valid DATA
1923 command is encountered. */
1926 if (sender_address
== NULL
|| recipients_count
<= 0)
1928 /* The function moan_smtp_batch() does not return. */
1929 if (sender_address
== NULL
)
1930 moan_smtp_batch(smtp_cmd_buffer
,
1931 "503 MAIL FROM:<sender> command must precede DATA");
1933 moan_smtp_batch(smtp_cmd_buffer
,
1934 "503 RCPT TO:<recipient> must precede DATA");
1938 done
= 3; /* DATA successfully achieved */
1939 message_ended
= END_NOTENDED
; /* Indicate in middle of message */
1944 /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */
1951 bsmtp_transaction_linecount
= receive_linecount
;
1962 /* The function moan_smtp_batch() does not return. */
1963 moan_smtp_batch(smtp_cmd_buffer
, "501 Unexpected argument data");
1968 /* The function moan_smtp_batch() does not return. */
1969 moan_smtp_batch(smtp_cmd_buffer
, "501 Unexpected NULL in SMTP command");
1974 /* The function moan_smtp_batch() does not return. */
1975 moan_smtp_batch(smtp_cmd_buffer
, "500 Command unrecognized");
1980 return done
- 2; /* Convert yield values */
1986 /*************************************************
1987 * Start an SMTP session *
1988 *************************************************/
1990 /* This function is called at the start of an SMTP session. Thereafter,
1991 smtp_setup_msg() is called to initiate each separate message. This
1992 function does host-specific testing, and outputs the banner line.
1995 Returns: FALSE if the session can not continue; something has
1996 gone wrong, or the connection to the host is blocked
2000 smtp_start_session(void)
2004 uschar
*user_msg
, *log_msg
;
2008 smtp_connection_start
= time(NULL
);
2009 for (smtp_ch_index
= 0; smtp_ch_index
< SMTP_HBUFF_SIZE
; smtp_ch_index
++)
2010 smtp_connection_had
[smtp_ch_index
] = SCH_NONE
;
2013 /* Default values for certain variables */
2015 helo_seen
= esmtp
= helo_accept_junk
= FALSE
;
2016 smtp_mailcmd_count
= 0;
2017 count_nonmail
= TRUE_UNSET
;
2018 synprot_error_count
= unknown_command_count
= nonmail_command_count
= 0;
2019 smtp_delay_mail
= smtp_rlm_base
;
2020 auth_advertised
= FALSE
;
2021 pipelining_advertised
= FALSE
;
2022 pipelining_enable
= TRUE
;
2023 sync_cmd_limit
= NON_SYNC_CMD_NON_PIPELINING
;
2024 smtp_exit_function_called
= FALSE
; /* For avoiding loop in not-quit exit */
2026 /* If receiving by -bs from a trusted user, or testing with -bh, we allow
2027 authentication settings from -oMaa to remain in force. */
2029 if (!host_checking
&& !sender_host_notsocket
) sender_host_authenticated
= NULL
;
2030 authenticated_by
= NULL
;
2033 tls_in
.cipher
= tls_in
.peerdn
= NULL
;
2034 tls_in
.ourcert
= tls_in
.peercert
= NULL
;
2036 tls_in
.ocsp
= OCSP_NOT_REQ
;
2037 tls_advertised
= FALSE
;
2039 dsn_advertised
= FALSE
;
2041 smtputf8_advertised
= FALSE
;
2044 /* Reset ACL connection variables */
2048 /* Allow for trailing 0 in the command and data buffers. */
2050 if (!(smtp_cmd_buffer
= US
malloc(2*smtp_cmd_buffer_size
+ 2)))
2051 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
,
2052 "malloc() failed for SMTP command buffer");
2054 smtp_cmd_buffer
[0] = 0;
2055 smtp_data_buffer
= smtp_cmd_buffer
+ smtp_cmd_buffer_size
+ 1;
2057 /* For batched input, the protocol setting can be overridden from the
2058 command line by a trusted caller. */
2060 if (smtp_batched_input
)
2062 if (!received_protocol
) received_protocol
= US
"local-bsmtp";
2065 /* For non-batched SMTP input, the protocol setting is forced here. It will be
2066 reset later if any of EHLO/AUTH/STARTTLS are received. */
2070 (sender_host_address
? protocols
: protocols_local
) [pnormal
];
2072 /* Set up the buffer for inputting using direct read() calls, and arrange to
2073 call the local functions instead of the standard C ones. */
2075 if (!(smtp_inbuffer
= (uschar
*)malloc(in_buffer_size
)))
2076 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "malloc() failed for SMTP input buffer");
2078 receive_getc
= smtp_getc
;
2079 receive_get_cache
= smtp_get_cache
;
2080 receive_ungetc
= smtp_ungetc
;
2081 receive_feof
= smtp_feof
;
2082 receive_ferror
= smtp_ferror
;
2083 receive_smtp_buffered
= smtp_buffered
;
2084 smtp_inptr
= smtp_inend
= smtp_inbuffer
;
2085 smtp_had_eof
= smtp_had_error
= 0;
2087 /* Set up the message size limit; this may be host-specific */
2089 thismessage_size_limit
= expand_string_integer(message_size_limit
, TRUE
);
2090 if (expand_string_message
!= NULL
)
2092 if (thismessage_size_limit
== -1)
2093 log_write(0, LOG_MAIN
|LOG_PANIC
, "unable to expand message_size_limit: "
2094 "%s", expand_string_message
);
2096 log_write(0, LOG_MAIN
|LOG_PANIC
, "invalid message_size_limit: "
2097 "%s", expand_string_message
);
2098 smtp_closedown(US
"Temporary local problem - please try later");
2102 /* When a message is input locally via the -bs or -bS options, sender_host_
2103 unknown is set unless -oMa was used to force an IP address, in which case it
2104 is checked like a real remote connection. When -bs is used from inetd, this
2105 flag is not set, causing the sending host to be checked. The code that deals
2106 with IP source routing (if configured) is never required for -bs or -bS and
2107 the flag sender_host_notsocket is used to suppress it.
2109 If smtp_accept_max and smtp_accept_reserve are set, keep some connections in
2110 reserve for certain hosts and/or networks. */
2112 if (!sender_host_unknown
)
2115 BOOL reserved_host
= FALSE
;
2117 /* Look up IP options (source routing info) on the socket if this is not an
2118 -oMa "host", and if any are found, log them and drop the connection.
2120 Linux (and others now, see below) is different to everyone else, so there
2121 has to be some conditional compilation here. Versions of Linux before 2.1.15
2122 used a structure whose name was "options". Somebody finally realized that
2123 this name was silly, and it got changed to "ip_options". I use the
2124 newer name here, but there is a fudge in the script that sets up os.h
2125 to define a macro in older Linux systems.
2127 Sigh. Linux is a fast-moving target. Another generation of Linux uses
2128 glibc 2, which has chosen ip_opts for the structure name. This is now
2129 really a glibc thing rather than a Linux thing, so the condition name
2130 has been changed to reflect this. It is relevant also to GNU/Hurd.
2132 Mac OS 10.x (Darwin) is like the later glibc versions, but without the
2133 setting of the __GLIBC__ macro, so we can't detect it automatically. There's
2134 a special macro defined in the os.h file.
2136 Some DGUX versions on older hardware appear not to support IP options at
2137 all, so there is now a general macro which can be set to cut out this
2140 How to do this properly in IPv6 is not yet known. */
2142 #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS)
2144 #ifdef GLIBC_IP_OPTIONS
2145 #if (!defined __GLIBC__) || (__GLIBC__ < 2)
2150 #elif defined DARWIN_IP_OPTIONS
2156 if (!host_checking
&& !sender_host_notsocket
)
2159 EXIM_SOCKLEN_T optlen
= sizeof(struct ip_options
) + MAX_IPOPTLEN
;
2160 struct ip_options
*ipopt
= store_get(optlen
);
2162 struct ip_opts ipoptblock
;
2163 struct ip_opts
*ipopt
= &ipoptblock
;
2164 EXIM_SOCKLEN_T optlen
= sizeof(ipoptblock
);
2166 struct ipoption ipoptblock
;
2167 struct ipoption
*ipopt
= &ipoptblock
;
2168 EXIM_SOCKLEN_T optlen
= sizeof(ipoptblock
);
2171 /* Occasional genuine failures of getsockopt() have been seen - for
2172 example, "reset by peer". Therefore, just log and give up on this
2173 call, unless the error is ENOPROTOOPT. This error is given by systems
2174 that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time
2175 of writing. So for that error, carry on - we just can't do an IP options
2178 DEBUG(D_receive
) debug_printf("checking for IP options\n");
2180 if (getsockopt(fileno(smtp_out
), IPPROTO_IP
, IP_OPTIONS
, (uschar
*)(ipopt
),
2183 if (errno
!= ENOPROTOOPT
)
2185 log_write(0, LOG_MAIN
, "getsockopt() failed from %s: %s",
2186 host_and_ident(FALSE
), strerror(errno
));
2187 smtp_printf("451 SMTP service not available\r\n");
2192 /* Deal with any IP options that are set. On the systems I have looked at,
2193 the value of MAX_IPOPTLEN has been 40, meaning that there should never be
2194 more logging data than will fit in big_buffer. Nevertheless, after somebody
2195 questioned this code, I've added in some paranoid checking. */
2197 else if (optlen
> 0)
2199 uschar
*p
= big_buffer
;
2200 uschar
*pend
= big_buffer
+ big_buffer_size
;
2201 uschar
*opt
, *adptr
;
2203 struct in_addr addr
;
2206 uschar
*optstart
= (uschar
*)(ipopt
->__data
);
2208 uschar
*optstart
= (uschar
*)(ipopt
->ip_opts
);
2210 uschar
*optstart
= (uschar
*)(ipopt
->ipopt_list
);
2213 DEBUG(D_receive
) debug_printf("IP options exist\n");
2215 Ustrcpy(p
, "IP options on incoming call:");
2218 for (opt
= optstart
; opt
!= NULL
&&
2219 opt
< (uschar
*)(ipopt
) + optlen
;)
2233 if (!string_format(p
, pend
-p
, " %s [@%s",
2234 (*opt
== IPOPT_SSRR
)? "SSRR" : "LSRR",
2236 inet_ntoa(*((struct in_addr
*)(&(ipopt
->faddr
))))))
2238 inet_ntoa(ipopt
->ip_dst
)))
2240 inet_ntoa(ipopt
->ipopt_dst
)))
2248 optcount
= (opt
[1] - 3) / sizeof(struct in_addr
);
2250 while (optcount
-- > 0)
2252 memcpy(&addr
, adptr
, sizeof(addr
));
2253 if (!string_format(p
, pend
- p
- 1, "%s%s",
2254 (optcount
== 0)? ":" : "@", inet_ntoa(addr
)))
2260 adptr
+= sizeof(struct in_addr
);
2269 if (pend
- p
< 4 + 3*opt
[1]) { opt
= NULL
; break; }
2272 for (i
= 0; i
< opt
[1]; i
++)
2274 sprintf(CS p
, "%2.2x ", opt
[i
]);
2285 log_write(0, LOG_MAIN
, "%s", big_buffer
);
2287 /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */
2289 log_write(0, LOG_MAIN
|LOG_REJECT
,
2290 "connection from %s refused (IP options)", host_and_ident(FALSE
));
2292 smtp_printf("554 SMTP service not available\r\n");
2296 /* Length of options = 0 => there are no options */
2298 else DEBUG(D_receive
) debug_printf("no IP options found\n");
2300 #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */
2302 /* Set keep-alive in socket options. The option is on by default. This
2303 setting is an attempt to get rid of some hanging connections that stick in
2304 read() when the remote end (usually a dialup) goes away. */
2306 if (smtp_accept_keepalive
&& !sender_host_notsocket
)
2307 ip_keepalive(fileno(smtp_out
), sender_host_address
, FALSE
);
2309 /* If the current host matches host_lookup, set the name by doing a
2310 reverse lookup. On failure, sender_host_name will be NULL and
2311 host_lookup_failed will be TRUE. This may or may not be serious - optional
2314 if (verify_check_host(&host_lookup
) == OK
)
2316 (void)host_name_lookup();
2317 host_build_sender_fullhost();
2320 /* Delay this until we have the full name, if it is looked up. */
2322 set_process_info("handling incoming connection from %s",
2323 host_and_ident(FALSE
));
2325 /* Expand smtp_receive_timeout, if needed */
2327 if (smtp_receive_timeout_s
)
2330 if ( !(exp
= expand_string(smtp_receive_timeout_s
))
2332 || (smtp_receive_timeout
= readconf_readtime(exp
, 0, FALSE
)) < 0
2334 log_write(0, LOG_MAIN
|LOG_PANIC
,
2335 "bad value for smtp_receive_timeout: '%s'", exp
? exp
: US
"");
2338 /* Start up TLS if tls_on_connect is set. This is for supporting the legacy
2339 smtps port for use with older style SSL MTAs. */
2342 if (tls_in
.on_connect
&& tls_server_start(tls_require_ciphers
) != OK
)
2346 /* Test for explicit connection rejection */
2348 if (verify_check_host(&host_reject_connection
) == OK
)
2350 log_write(L_connection_reject
, LOG_MAIN
|LOG_REJECT
, "refused connection "
2351 "from %s (host_reject_connection)", host_and_ident(FALSE
));
2352 smtp_printf("554 SMTP service not available\r\n");
2356 /* Test with TCP Wrappers if so configured. There is a problem in that
2357 hosts_ctl() returns 0 (deny) under a number of system failure circumstances,
2358 such as disks dying. In these cases, it is desirable to reject with a 4xx
2359 error instead of a 5xx error. There isn't a "right" way to detect such
2360 problems. The following kludge is used: errno is zeroed before calling
2361 hosts_ctl(). If the result is "reject", a 5xx error is given only if the
2362 value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does
2365 #ifdef USE_TCP_WRAPPERS
2367 tcp_wrappers_name
= expand_string(tcp_wrappers_daemon_name
);
2368 if (tcp_wrappers_name
== NULL
)
2370 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "Expansion of \"%s\" "
2371 "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name
),
2372 expand_string_message
);
2374 if (!hosts_ctl(tcp_wrappers_name
,
2375 (sender_host_name
== NULL
)? STRING_UNKNOWN
: CS sender_host_name
,
2376 (sender_host_address
== NULL
)? STRING_UNKNOWN
: CS sender_host_address
,
2377 (sender_ident
== NULL
)? STRING_UNKNOWN
: CS sender_ident
))
2379 if (errno
== 0 || errno
== ENOENT
)
2381 HDEBUG(D_receive
) debug_printf("tcp wrappers rejection\n");
2382 log_write(L_connection_reject
,
2383 LOG_MAIN
|LOG_REJECT
, "refused connection from %s "
2384 "(tcp wrappers)", host_and_ident(FALSE
));
2385 smtp_printf("554 SMTP service not available\r\n");
2389 int save_errno
= errno
;
2390 HDEBUG(D_receive
) debug_printf("tcp wrappers rejected with unexpected "
2391 "errno value %d\n", save_errno
);
2392 log_write(L_connection_reject
,
2393 LOG_MAIN
|LOG_REJECT
, "temporarily refused connection from %s "
2394 "(tcp wrappers errno=%d)", host_and_ident(FALSE
), save_errno
);
2395 smtp_printf("451 Temporary local problem - please try later\r\n");
2401 /* Check for reserved slots. The value of smtp_accept_count has already been
2402 incremented to include this process. */
2404 if (smtp_accept_max
> 0 &&
2405 smtp_accept_count
> smtp_accept_max
- smtp_accept_reserve
)
2407 if ((rc
= verify_check_host(&smtp_reserve_hosts
)) != OK
)
2409 log_write(L_connection_reject
,
2410 LOG_MAIN
, "temporarily refused connection from %s: not in "
2411 "reserve list: connected=%d max=%d reserve=%d%s",
2412 host_and_ident(FALSE
), smtp_accept_count
- 1, smtp_accept_max
,
2413 smtp_accept_reserve
, (rc
== DEFER
)? " (lookup deferred)" : "");
2414 smtp_printf("421 %s: Too many concurrent SMTP connections; "
2415 "please try again later\r\n", smtp_active_hostname
);
2418 reserved_host
= TRUE
;
2421 /* If a load level above which only messages from reserved hosts are
2422 accepted is set, check the load. For incoming calls via the daemon, the
2423 check is done in the superior process if there are no reserved hosts, to
2424 save a fork. In all cases, the load average will already be available
2425 in a global variable at this point. */
2427 if (smtp_load_reserve
>= 0 &&
2428 load_average
> smtp_load_reserve
&&
2430 verify_check_host(&smtp_reserve_hosts
) != OK
)
2432 log_write(L_connection_reject
,
2433 LOG_MAIN
, "temporarily refused connection from %s: not in "
2434 "reserve list and load average = %.2f", host_and_ident(FALSE
),
2435 (double)load_average
/1000.0);
2436 smtp_printf("421 %s: Too much load; please try again later\r\n",
2437 smtp_active_hostname
);
2441 /* Determine whether unqualified senders or recipients are permitted
2442 for this host. Unfortunately, we have to do this every time, in order to
2443 set the flags so that they can be inspected when considering qualifying
2444 addresses in the headers. For a site that permits no qualification, this
2445 won't take long, however. */
2447 allow_unqualified_sender
=
2448 verify_check_host(&sender_unqualified_hosts
) == OK
;
2450 allow_unqualified_recipient
=
2451 verify_check_host(&recipient_unqualified_hosts
) == OK
;
2453 /* Determine whether HELO/EHLO is required for this host. The requirement
2454 can be hard or soft. */
2456 helo_required
= verify_check_host(&helo_verify_hosts
) == OK
;
2458 helo_verify
= verify_check_host(&helo_try_verify_hosts
) == OK
;
2460 /* Determine whether this hosts is permitted to send syntactic junk
2461 after a HELO or EHLO command. */
2463 helo_accept_junk
= verify_check_host(&helo_accept_junk_hosts
) == OK
;
2466 /* For batch SMTP input we are now done. */
2468 if (smtp_batched_input
) return TRUE
;
2470 #ifdef SUPPORT_PROXY
2471 /* If valid Proxy Protocol source is connecting, set up session.
2472 * Failure will not allow any SMTP function other than QUIT. */
2473 proxy_session
= FALSE
;
2474 proxy_session_failed
= FALSE
;
2475 if (check_proxy_protocol_host())
2476 if (setup_proxy_protocol_host() == FALSE
)
2478 proxy_session_failed
= TRUE
;
2480 debug_printf("Failure to extract proxied host, only QUIT allowed\n");
2484 sender_host_name
= NULL
;
2485 (void)host_name_lookup();
2486 host_build_sender_fullhost();
2490 /* Run the ACL if it exists */
2493 if (acl_smtp_connect
)
2496 if ((rc
= acl_check(ACL_WHERE_CONNECT
, NULL
, acl_smtp_connect
, &user_msg
,
2499 (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT
, rc
, user_msg
, log_msg
);
2504 /* Output the initial message for a two-way SMTP connection. It may contain
2505 newlines, which then cause a multi-line response to be given. */
2507 code
= US
"220"; /* Default status code */
2508 esc
= US
""; /* Default extended status code */
2509 esclen
= 0; /* Length of esc */
2513 if (!(s
= expand_string(smtp_banner
)))
2514 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "Expansion of \"%s\" (smtp_banner) "
2515 "failed: %s", smtp_banner
, expand_string_message
);
2521 smtp_message_code(&code
, &codelen
, &s
, NULL
, TRUE
);
2525 esclen
= codelen
- 4;
2529 /* Remove any terminating newlines; might as well remove trailing space too */
2532 while (p
> s
&& isspace(p
[-1])) p
--;
2535 /* It seems that CC:Mail is braindead, and assumes that the greeting message
2536 is all contained in a single IP packet. The original code wrote out the
2537 greeting using several calls to fprint/fputc, and on busy servers this could
2538 cause it to be split over more than one packet - which caused CC:Mail to fall
2539 over when it got the second part of the greeting after sending its first
2540 command. Sigh. To try to avoid this, build the complete greeting message
2541 first, and output it in one fell swoop. This gives a better chance of it
2542 ending up as a single packet. */
2544 ss
= store_get(size
);
2548 do /* At least once, in case we have an empty string */
2551 uschar
*linebreak
= Ustrchr(p
, '\n');
2552 ss
= string_catn(ss
, &size
, &ptr
, code
, 3);
2553 if (linebreak
== NULL
)
2556 ss
= string_catn(ss
, &size
, &ptr
, US
" ", 1);
2560 len
= linebreak
- p
;
2561 ss
= string_catn(ss
, &size
, &ptr
, US
"-", 1);
2563 ss
= string_catn(ss
, &size
, &ptr
, esc
, esclen
);
2564 ss
= string_catn(ss
, &size
, &ptr
, p
, len
);
2565 ss
= string_catn(ss
, &size
, &ptr
, US
"\r\n", 2);
2567 if (linebreak
!= NULL
) p
++;
2571 ss
[ptr
] = 0; /* string_cat leaves room for this */
2573 /* Before we write the banner, check that there is no input pending, unless
2574 this synchronisation check is disabled. */
2578 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP protocol "
2579 "synchronization error (input sent without waiting for greeting): "
2580 "rejected connection from %s input=\"%s\"", host_and_ident(TRUE
),
2581 string_printing(smtp_inptr
));
2582 smtp_printf("554 SMTP synchronization error\r\n");
2586 /* Now output the banner */
2588 smtp_printf("%s", ss
);
2596 /*************************************************
2597 * Handle SMTP syntax and protocol errors *
2598 *************************************************/
2600 /* Write to the log for SMTP syntax errors in incoming commands, if configured
2601 to do so. Then transmit the error response. The return value depends on the
2602 number of syntax and protocol errors in this SMTP session.
2605 type error type, given as a log flag bit
2606 code response code; <= 0 means don't send a response
2607 data data to reflect in the response (can be NULL)
2608 errmess the error message
2610 Returns: -1 limit of syntax/protocol errors NOT exceeded
2611 +1 limit of syntax/protocol errors IS exceeded
2613 These values fit in with the values of the "done" variable in the main
2614 processing loop in smtp_setup_msg(). */
2617 synprot_error(int type
, int code
, uschar
*data
, uschar
*errmess
)
2621 log_write(type
, LOG_MAIN
, "SMTP %s error in \"%s\" %s %s",
2622 (type
== L_smtp_syntax_error
)? "syntax" : "protocol",
2623 string_printing(smtp_cmd_buffer
), host_and_ident(TRUE
), errmess
);
2625 if (++synprot_error_count
> smtp_max_synprot_errors
)
2628 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
2629 "syntax or protocol errors (last command was \"%s\")",
2630 host_and_ident(FALSE
), string_printing(smtp_cmd_buffer
));
2635 smtp_printf("%d%c%s%s%s\r\n", code
, (yield
== 1)? '-' : ' ',
2636 (data
== NULL
)? US
"" : data
, (data
== NULL
)? US
"" : US
": ", errmess
);
2638 smtp_printf("%d Too many syntax or protocol errors\r\n", code
);
2647 /*************************************************
2648 * Log incomplete transactions *
2649 *************************************************/
2651 /* This function is called after a transaction has been aborted by RSET, QUIT,
2652 connection drops or other errors. It logs the envelope information received
2653 so far in order to preserve address verification attempts.
2655 Argument: string to indicate what aborted the transaction
2660 incomplete_transaction_log(uschar
*what
)
2662 if (sender_address
== NULL
|| /* No transaction in progress */
2663 !LOGGING(smtp_incomplete_transaction
))
2666 /* Build list of recipients for logging */
2668 if (recipients_count
> 0)
2671 raw_recipients
= store_get(recipients_count
* sizeof(uschar
*));
2672 for (i
= 0; i
< recipients_count
; i
++)
2673 raw_recipients
[i
] = recipients_list
[i
].address
;
2674 raw_recipients_count
= recipients_count
;
2677 log_write(L_smtp_incomplete_transaction
, LOG_MAIN
|LOG_SENDER
|LOG_RECIPIENTS
,
2678 "%s incomplete transaction (%s)", host_and_ident(TRUE
), what
);
2684 /*************************************************
2685 * Send SMTP response, possibly multiline *
2686 *************************************************/
2688 /* There are, it seems, broken clients out there that cannot handle multiline
2689 responses. If no_multiline_responses is TRUE (it can be set from an ACL), we
2690 output nothing for non-final calls, and only the first line for anything else.
2693 code SMTP code, may involve extended status codes
2694 codelen length of smtp code; if > 4 there's an ESC
2695 final FALSE if the last line isn't the final line
2696 msg message text, possibly containing newlines
2702 smtp_respond(uschar
* code
, int codelen
, BOOL final
, uschar
*msg
)
2707 if (!final
&& no_multiline_responses
) return;
2712 esclen
= codelen
- 4;
2715 /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs
2716 have had the same. Note: this code is also present in smtp_printf(). It would
2717 be tidier to have it only in one place, but when it was added, it was easier to
2718 do it that way, so as not to have to mess with the code for the RCPT command,
2719 which sometimes uses smtp_printf() and sometimes smtp_respond(). */
2721 if (rcpt_in_progress
)
2723 if (rcpt_smtp_response
== NULL
)
2724 rcpt_smtp_response
= string_copy(msg
);
2725 else if (rcpt_smtp_response_same
&&
2726 Ustrcmp(rcpt_smtp_response
, msg
) != 0)
2727 rcpt_smtp_response_same
= FALSE
;
2728 rcpt_in_progress
= FALSE
;
2731 /* Not output the message, splitting it up into multiple lines if necessary. */
2735 uschar
*nl
= Ustrchr(msg
, '\n');
2738 smtp_printf("%.3s%c%.*s%s\r\n", code
, final
? ' ':'-', esclen
, esc
, msg
);
2741 else if (nl
[1] == 0 || no_multiline_responses
)
2743 smtp_printf("%.3s%c%.*s%.*s\r\n", code
, final
? ' ':'-', esclen
, esc
,
2744 (int)(nl
- msg
), msg
);
2749 smtp_printf("%.3s-%.*s%.*s\r\n", code
, esclen
, esc
, (int)(nl
- msg
), msg
);
2751 while (isspace(*msg
)) msg
++;
2759 /*************************************************
2760 * Parse user SMTP message *
2761 *************************************************/
2763 /* This function allows for user messages overriding the response code details
2764 by providing a suitable response code string at the start of the message
2765 user_msg. Check the message for starting with a response code and optionally an
2766 extended status code. If found, check that the first digit is valid, and if so,
2767 change the code pointer and length to use the replacement. An invalid code
2768 causes a panic log; in this case, if the log messages is the same as the user
2769 message, we must also adjust the value of the log message to show the code that
2770 is actually going to be used (the original one).
2772 This function is global because it is called from receive.c as well as within
2775 Note that the code length returned includes the terminating whitespace
2776 character, which is always included in the regex match.
2779 code SMTP code, may involve extended status codes
2780 codelen length of smtp code; if > 4 there's an ESC
2782 log_msg optional log message, to be adjusted with the new SMTP code
2783 check_valid if true, verify the response code
2789 smtp_message_code(uschar
**code
, int *codelen
, uschar
**msg
, uschar
**log_msg
,
2795 if (!msg
|| !*msg
) return;
2797 if ((n
= pcre_exec(regex_smtp_code
, NULL
, CS
*msg
, Ustrlen(*msg
), 0,
2798 PCRE_EOPT
, ovector
, sizeof(ovector
)/sizeof(int))) < 0) return;
2800 if (check_valid
&& (*msg
)[0] != (*code
)[0])
2802 log_write(0, LOG_MAIN
|LOG_PANIC
, "configured error code starts with "
2803 "incorrect digit (expected %c) in \"%s\"", (*code
)[0], *msg
);
2804 if (log_msg
!= NULL
&& *log_msg
== *msg
)
2805 *log_msg
= string_sprintf("%s %s", *code
, *log_msg
+ ovector
[1]);
2810 *codelen
= ovector
[1]; /* Includes final space */
2812 *msg
+= ovector
[1]; /* Chop the code off the message */
2819 /*************************************************
2820 * Handle an ACL failure *
2821 *************************************************/
2823 /* This function is called when acl_check() fails. As well as calls from within
2824 this module, it is called from receive.c for an ACL after DATA. It sorts out
2825 logging the incident, and sets up the error response. A message containing
2826 newlines is turned into a multiline SMTP response, but for logging, only the
2829 There's a table of default permanent failure response codes to use in
2830 globals.c, along with the table of names. VFRY is special. Despite RFC1123 it
2831 defaults disabled in Exim. However, discussion in connection with RFC 821bis
2832 (aka RFC 2821) has concluded that the response should be 252 in the disabled
2833 state, because there are broken clients that try VRFY before RCPT. A 5xx
2834 response should be given only when the address is positively known to be
2835 undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides
2836 no explicit code, but if there is one we let it know best.
2837 Also, for ETRN, 458 is given on refusal, and for AUTH, 503.
2839 From Exim 4.63, it is possible to override the response code details by
2840 providing a suitable response code string at the start of the message provided
2841 in user_msg. The code's first digit is checked for validity.
2844 where where the ACL was called from
2846 user_msg a message that can be included in an SMTP response
2847 log_msg a message for logging
2849 Returns: 0 in most cases
2850 2 if the failure code was FAIL_DROP, in which case the
2851 SMTP connection should be dropped (this value fits with the
2852 "done" variable in smtp_setup_msg() below)
2856 smtp_handle_acl_fail(int where
, int rc
, uschar
*user_msg
, uschar
*log_msg
)
2858 BOOL drop
= rc
== FAIL_DROP
;
2862 uschar
*sender_info
= US
"";
2864 #ifdef WITH_CONTENT_SCAN
2865 where
== ACL_WHERE_MIME
? US
"during MIME ACL checks" :
2867 where
== ACL_WHERE_PREDATA
? US
"DATA" :
2868 where
== ACL_WHERE_DATA
? US
"after DATA" :
2869 #ifndef DISABLE_PRDR
2870 where
== ACL_WHERE_PRDR
? US
"after DATA PRDR" :
2873 string_sprintf("%s %s", acl_wherenames
[where
], smtp_cmd_data
) :
2874 string_sprintf("%s in \"connect\" ACL", acl_wherenames
[where
]);
2876 if (drop
) rc
= FAIL
;
2878 /* Set the default SMTP code, and allow a user message to change it. */
2880 smtp_code
= rc
== FAIL
? acl_wherecodes
[where
] : US
"451";
2881 smtp_message_code(&smtp_code
, &codelen
, &user_msg
, &log_msg
,
2882 where
!= ACL_WHERE_VRFY
);
2884 /* We used to have sender_address here; however, there was a bug that was not
2885 updating sender_address after a rewrite during a verify. When this bug was
2886 fixed, sender_address at this point became the rewritten address. I'm not sure
2887 this is what should be logged, so I've changed to logging the unrewritten
2888 address to retain backward compatibility. */
2890 #ifndef WITH_CONTENT_SCAN
2891 if (where
== ACL_WHERE_RCPT
|| where
== ACL_WHERE_DATA
)
2893 if (where
== ACL_WHERE_RCPT
|| where
== ACL_WHERE_DATA
|| where
== ACL_WHERE_MIME
)
2896 sender_info
= string_sprintf("F=<%s>%s%s%s%s ",
2897 sender_address_unrewritten
? sender_address_unrewritten
: sender_address
,
2898 sender_host_authenticated
? US
" A=" : US
"",
2899 sender_host_authenticated
? sender_host_authenticated
: US
"",
2900 sender_host_authenticated
&& authenticated_id
? US
":" : US
"",
2901 sender_host_authenticated
&& authenticated_id
? authenticated_id
: US
""
2905 /* If there's been a sender verification failure with a specific message, and
2906 we have not sent a response about it yet, do so now, as a preliminary line for
2907 failures, but not defers. However, always log it for defer, and log it for fail
2908 unless the sender_verify_fail log selector has been turned off. */
2910 if (sender_verified_failed
!= NULL
&&
2911 !testflag(sender_verified_failed
, af_sverify_told
))
2913 BOOL save_rcpt_in_progress
= rcpt_in_progress
;
2914 rcpt_in_progress
= FALSE
; /* So as not to treat these as the error */
2916 setflag(sender_verified_failed
, af_sverify_told
);
2918 if (rc
!= FAIL
|| LOGGING(sender_verify_fail
))
2919 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s sender verify %s for <%s>%s",
2920 host_and_ident(TRUE
),
2921 ((sender_verified_failed
->special_action
& 255) == DEFER
)? "defer":"fail",
2922 sender_verified_failed
->address
,
2923 (sender_verified_failed
->message
== NULL
)? US
"" :
2924 string_sprintf(": %s", sender_verified_failed
->message
));
2926 if (rc
== FAIL
&& sender_verified_failed
->user_message
!= NULL
)
2927 smtp_respond(smtp_code
, codelen
, FALSE
, string_sprintf(
2928 testflag(sender_verified_failed
, af_verify_pmfail
)?
2929 "Postmaster verification failed while checking <%s>\n%s\n"
2930 "Several RFCs state that you are required to have a postmaster\n"
2931 "mailbox for each mail domain. This host does not accept mail\n"
2932 "from domains whose servers reject the postmaster address."
2934 testflag(sender_verified_failed
, af_verify_nsfail
)?
2935 "Callback setup failed while verifying <%s>\n%s\n"
2936 "The initial connection, or a HELO or MAIL FROM:<> command was\n"
2937 "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n"
2938 "RFC requirements, and stops you from receiving standard bounce\n"
2939 "messages. This host does not accept mail from domains whose servers\n"
2942 "Verification failed for <%s>\n%s",
2943 sender_verified_failed
->address
,
2944 sender_verified_failed
->user_message
));
2946 rcpt_in_progress
= save_rcpt_in_progress
;
2949 /* Sort out text for logging */
2951 log_msg
= log_msg
? string_sprintf(": %s", log_msg
) : US
"";
2952 if ((lognl
= Ustrchr(log_msg
, '\n'))) *lognl
= 0;
2954 /* Send permanent failure response to the command, but the code used isn't
2955 always a 5xx one - see comments at the start of this function. If the original
2956 rc was FAIL_DROP we drop the connection and yield 2. */
2959 smtp_respond(smtp_code
, codelen
, TRUE
,
2960 user_msg
? user_msg
: US
"Administrative prohibition");
2962 /* Send temporary failure response to the command. Don't give any details,
2963 unless acl_temp_details is set. This is TRUE for a callout defer, a "defer"
2964 verb, and for a header verify when smtp_return_error_details is set.
2966 This conditional logic is all somewhat of a mess because of the odd
2967 interactions between temp_details and return_error_details. One day it should
2968 be re-implemented in a tidier fashion. */
2971 if (acl_temp_details
&& user_msg
)
2973 if ( smtp_return_error_details
2974 && sender_verified_failed
2975 && sender_verified_failed
->message
2977 smtp_respond(smtp_code
, codelen
, FALSE
, sender_verified_failed
->message
);
2979 smtp_respond(smtp_code
, codelen
, TRUE
, user_msg
);
2982 smtp_respond(smtp_code
, codelen
, TRUE
,
2983 US
"Temporary local problem - please try later");
2985 /* Log the incident to the logs that are specified by log_reject_target
2986 (default main, reject). This can be empty to suppress logging of rejections. If
2987 the connection is not forcibly to be dropped, return 0. Otherwise, log why it
2988 is closing if required and return 2. */
2990 if (log_reject_target
!= 0)
2993 uschar
* tls
= s_tlslog(NULL
, NULL
, NULL
);
2994 if (!tls
) tls
= US
"";
2996 uschar
* tls
= US
"";
2998 log_write(where
== ACL_WHERE_CONNECT
? L_connection_reject
: 0,
2999 log_reject_target
, "%s%s%s %s%srejected %s%s",
3000 LOGGING(dnssec
) && sender_host_dnssec
? US
" DS" : US
"",
3001 host_and_ident(TRUE
),
3004 rc
== FAIL
? US
"" : US
"temporarily ",
3008 if (!drop
) return 0;
3010 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by DROP in ACL",
3011 smtp_get_connection_info());
3013 /* Run the not-quit ACL, but without any custom messages. This should not be a
3014 problem, because we get here only if some other ACL has issued "drop", and
3015 in that case, *its* custom messages will have been used above. */
3017 smtp_notquit_exit(US
"acl-drop", NULL
, NULL
);
3024 /*************************************************
3025 * Handle SMTP exit when QUIT is not given *
3026 *************************************************/
3028 /* This function provides a logging/statistics hook for when an SMTP connection
3029 is dropped on the floor or the other end goes away. It's a global function
3030 because it's called from receive.c as well as this module. As well as running
3031 the NOTQUIT ACL, if there is one, this function also outputs a final SMTP
3032 response, either with a custom message from the ACL, or using a default. There
3033 is one case, however, when no message is output - after "drop". In that case,
3034 the ACL that obeyed "drop" has already supplied the custom message, and NULL is
3035 passed to this function.
3037 In case things go wrong while processing this function, causing an error that
3038 may re-enter this funtion, there is a recursion check.
3041 reason What $smtp_notquit_reason will be set to in the ACL;
3042 if NULL, the ACL is not run
3043 code The error code to return as part of the response
3044 defaultrespond The default message if there's no user_msg
3050 smtp_notquit_exit(uschar
*reason
, uschar
*code
, uschar
*defaultrespond
, ...)
3053 uschar
*user_msg
= NULL
;
3054 uschar
*log_msg
= NULL
;
3056 /* Check for recursive acll */
3058 if (smtp_exit_function_called
)
3060 log_write(0, LOG_PANIC
, "smtp_notquit_exit() called more than once (%s)",
3064 smtp_exit_function_called
= TRUE
;
3066 /* Call the not-QUIT ACL, if there is one, unless no reason is given. */
3068 if (acl_smtp_notquit
&& reason
)
3070 smtp_notquit_reason
= reason
;
3071 if ((rc
= acl_check(ACL_WHERE_NOTQUIT
, NULL
, acl_smtp_notquit
, &user_msg
,
3072 &log_msg
)) == ERROR
)
3073 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for not-QUIT returned ERROR: %s",
3077 /* Write an SMTP response if we are expected to give one. As the default
3078 responses are all internal, they should always fit in the buffer, but code a
3079 warning, just in case. Note that string_vformat() still leaves a complete
3080 string, even if it is incomplete. */
3082 if (code
&& defaultrespond
)
3085 smtp_respond(code
, 3, TRUE
, user_msg
);
3090 va_start(ap
, defaultrespond
);
3091 if (!string_vformat(buffer
, sizeof(buffer
), CS defaultrespond
, ap
))
3092 log_write(0, LOG_MAIN
|LOG_PANIC
, "string too large in smtp_notquit_exit()");
3093 smtp_printf("%s %s\r\n", code
, buffer
);
3103 /*************************************************
3104 * Verify HELO argument *
3105 *************************************************/
3107 /* This function is called if helo_verify_hosts or helo_try_verify_hosts is
3108 matched. It is also called from ACL processing if verify = helo is used and
3109 verification was not previously tried (i.e. helo_try_verify_hosts was not
3110 matched). The result of its processing is to set helo_verified and
3111 helo_verify_failed. These variables should both be FALSE for this function to
3114 Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow
3115 for IPv6 ::ffff: literals.
3118 Returns: TRUE if testing was completed;
3119 FALSE on a temporary failure
3123 smtp_verify_helo(void)
3127 HDEBUG(D_receive
) debug_printf("verifying EHLO/HELO argument \"%s\"\n",
3130 if (sender_helo_name
== NULL
)
3132 HDEBUG(D_receive
) debug_printf("no EHLO/HELO command was issued\n");
3135 /* Deal with the case of -bs without an IP address */
3137 else if (sender_host_address
== NULL
)
3139 HDEBUG(D_receive
) debug_printf("no client IP address: assume success\n");
3140 helo_verified
= TRUE
;
3143 /* Deal with the more common case when there is a sending IP address */
3145 else if (sender_helo_name
[0] == '[')
3147 helo_verified
= Ustrncmp(sender_helo_name
+1, sender_host_address
,
3148 Ustrlen(sender_host_address
)) == 0;
3153 if (strncmpic(sender_host_address
, US
"::ffff:", 7) == 0)
3154 helo_verified
= Ustrncmp(sender_helo_name
+ 1,
3155 sender_host_address
+ 7, Ustrlen(sender_host_address
) - 7) == 0;
3160 { if (helo_verified
) debug_printf("matched host address\n"); }
3163 /* Do a reverse lookup if one hasn't already given a positive or negative
3164 response. If that fails, or the name doesn't match, try checking with a forward
3169 if (sender_host_name
== NULL
&& !host_lookup_failed
)
3170 yield
= host_name_lookup() != DEFER
;
3172 /* If a host name is known, check it and all its aliases. */
3174 if (sender_host_name
)
3175 if ((helo_verified
= strcmpic(sender_host_name
, sender_helo_name
) == 0))
3177 sender_helo_dnssec
= sender_host_dnssec
;
3178 HDEBUG(D_receive
) debug_printf("matched host name\n");
3182 uschar
**aliases
= sender_host_aliases
;
3184 if ((helo_verified
= strcmpic(*aliases
++, sender_helo_name
) == 0))
3186 sender_helo_dnssec
= sender_host_dnssec
;
3190 HDEBUG(D_receive
) if (helo_verified
)
3191 debug_printf("matched alias %s\n", *(--aliases
));
3194 /* Final attempt: try a forward lookup of the helo name */
3203 h
.name
= sender_helo_name
;
3210 HDEBUG(D_receive
) debug_printf("getting IP address for %s\n",
3212 rc
= host_find_bydns(&h
, NULL
, HOST_FIND_BY_A
,
3213 NULL
, NULL
, NULL
, &d
, NULL
, NULL
);
3214 if (rc
== HOST_FOUND
|| rc
== HOST_FOUND_LOCAL
)
3215 for (hh
= &h
; hh
; hh
= hh
->next
)
3216 if (Ustrcmp(hh
->address
, sender_host_address
) == 0)
3218 helo_verified
= TRUE
;
3219 if (h
.dnssec
== DS_YES
) sender_helo_dnssec
= TRUE
;
3222 debug_printf("IP address for %s matches calling address\n"
3223 "Forward DNS security status: %sverified\n",
3224 sender_helo_name
, sender_helo_dnssec
? "" : "un");
3231 if (!helo_verified
) helo_verify_failed
= TRUE
; /* We've tried ... */
3238 /*************************************************
3239 * Send user response message *
3240 *************************************************/
3242 /* This function is passed a default response code and a user message. It calls
3243 smtp_message_code() to check and possibly modify the response code, and then
3244 calls smtp_respond() to transmit the response. I put this into a function
3245 just to avoid a lot of repetition.
3248 code the response code
3249 user_msg the user message
3255 smtp_user_msg(uschar
*code
, uschar
*user_msg
)
3258 smtp_message_code(&code
, &len
, &user_msg
, NULL
, TRUE
);
3259 smtp_respond(code
, len
, TRUE
, user_msg
);
3265 smtp_in_auth(auth_instance
*au
, uschar
** s
, uschar
** ss
)
3267 const uschar
*set_id
= NULL
;
3270 /* Run the checking code, passing the remainder of the command line as
3271 data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
3272 it as the only set numerical variable. The authenticator may set $auth<n>
3273 and also set other numeric variables. The $auth<n> variables are preferred
3274 nowadays; the numerical variables remain for backwards compatibility.
3276 Afterwards, have a go at expanding the set_id string, even if
3277 authentication failed - for bad passwords it can be useful to log the
3278 userid. On success, require set_id to expand and exist, and put it in
3279 authenticated_id. Save this in permanent store, as the working store gets
3280 reset at HELO, RSET, etc. */
3282 for (i
= 0; i
< AUTH_VARS
; i
++) auth_vars
[i
] = NULL
;
3284 expand_nlength
[0] = 0; /* $0 contains nothing */
3286 rc
= (au
->info
->servercode
)(au
, smtp_cmd_data
);
3287 if (au
->set_id
) set_id
= expand_string(au
->set_id
);
3288 expand_nmax
= -1; /* Reset numeric variables */
3289 for (i
= 0; i
< AUTH_VARS
; i
++) auth_vars
[i
] = NULL
; /* Reset $auth<n> */
3291 /* The value of authenticated_id is stored in the spool file and printed in
3292 log lines. It must not contain binary zeros or newline characters. In
3293 normal use, it never will, but when playing around or testing, this error
3294 can (did) happen. To guard against this, ensure that the id contains only
3295 printing characters. */
3297 if (set_id
) set_id
= string_printing(set_id
);
3299 /* For the non-OK cases, set up additional logging data if set_id
3303 set_id
= set_id
&& *set_id
3304 ? string_sprintf(" (set_id=%s)", set_id
) : US
"";
3306 /* Switch on the result */
3311 if (!au
->set_id
|| set_id
) /* Complete success */
3313 if (set_id
) authenticated_id
= string_copy_malloc(set_id
);
3314 sender_host_authenticated
= au
->name
;
3315 authentication_failed
= FALSE
;
3316 authenticated_fail_id
= NULL
; /* Impossible to already be set? */
3319 (sender_host_address
? protocols
: protocols_local
)
3320 [pextend
+ pauthed
+ (tls_in
.active
>= 0 ? pcrpted
:0)];
3321 *s
= *ss
= US
"235 Authentication succeeded";
3322 authenticated_by
= au
;
3326 /* Authentication succeeded, but we failed to expand the set_id string.
3327 Treat this as a temporary error. */
3329 auth_defer_msg
= expand_string_message
;
3333 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3334 *s
= string_sprintf("435 Unable to authenticate at present%s",
3335 auth_defer_user_msg
);
3336 *ss
= string_sprintf("435 Unable to authenticate at present%s: %s",
3337 set_id
, auth_defer_msg
);
3341 *s
= *ss
= US
"501 Invalid base64 data";
3345 *s
= *ss
= US
"501 Authentication cancelled";
3349 *s
= *ss
= US
"553 Initial data not expected";
3353 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3354 *s
= US
"535 Incorrect authentication data";
3355 *ss
= string_sprintf("535 Incorrect authentication data%s", set_id
);
3359 if (set_id
) authenticated_fail_id
= string_copy_malloc(set_id
);
3360 *s
= US
"435 Internal error";
3361 *ss
= string_sprintf("435 Internal error%s: return %d from authentication "
3362 "check", set_id
, rc
);
3374 qualify_recipient(uschar
** recipient
, uschar
* smtp_cmd_data
, uschar
* tag
)
3377 if (allow_unqualified_recipient
|| strcmpic(*recipient
, US
"postmaster") == 0)
3379 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
3381 rd
= Ustrlen(recipient
) + 1;
3382 *recipient
= rewrite_address_qualify(*recipient
, TRUE
);
3385 smtp_printf("501 %s: recipient address must contain a domain\r\n",
3387 log_write(L_smtp_syntax_error
,
3388 LOG_MAIN
|LOG_REJECT
, "unqualified %s rejected: <%s> %s%s",
3389 tag
, *recipient
, host_and_ident(TRUE
), host_lookup_msg
);
3397 smtp_quit_handler(uschar
** user_msgp
, uschar
** log_msgp
)
3400 incomplete_transaction_log(US
"QUIT");
3403 int rc
= acl_check(ACL_WHERE_QUIT
, NULL
, acl_smtp_quit
, user_msgp
, log_msgp
);
3405 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for QUIT returned ERROR: %s",
3409 smtp_respond(US
"221", 3, TRUE
, *user_msgp
);
3411 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
3414 tls_close(TRUE
, TRUE
);
3417 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by QUIT",
3418 smtp_get_connection_info());
3423 smtp_rset_handler(void)
3426 incomplete_transaction_log(US
"RSET");
3427 smtp_printf("250 Reset OK\r\n");
3428 cmd_list
[CMD_LIST_RSET
].is_mail_cmd
= FALSE
;
3433 /*************************************************
3434 * Initialize for SMTP incoming message *
3435 *************************************************/
3437 /* This function conducts the initial dialogue at the start of an incoming SMTP
3438 message, and builds a list of recipients. However, if the incoming message
3439 is part of a batch (-bS option) a separate function is called since it would
3440 be messy having tests splattered about all over this function. This function
3441 therefore handles the case where interaction is occurring. The input and output
3442 files are set up in smtp_in and smtp_out.
3444 The global recipients_list is set to point to a vector of recipient_item
3445 blocks, whose number is given by recipients_count. This is extended by the
3446 receive_add_recipient() function. The global variable sender_address is set to
3447 the sender's address. The yield is +1 if a message has been successfully
3448 started, 0 if a QUIT command was encountered or the connection was refused from
3449 the particular host, or -1 if the connection was lost.
3453 Returns: > 0 message successfully started (reached DATA)
3454 = 0 QUIT read or end of file reached or call refused
3459 smtp_setup_msg(void)
3462 BOOL toomany
= FALSE
;
3463 BOOL discarded
= FALSE
;
3464 BOOL last_was_rej_mail
= FALSE
;
3465 BOOL last_was_rcpt
= FALSE
;
3466 void *reset_point
= store_get(0);
3468 DEBUG(D_receive
) debug_printf("smtp_setup_msg entered\n");
3470 /* Reset for start of new message. We allow one RSET not to be counted as a
3471 nonmail command, for those MTAs that insist on sending it between every
3472 message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of
3473 TLS between messages (an Exim client may do this if it has messages queued up
3474 for the host). Note: we do NOT reset AUTH at this point. */
3476 smtp_reset(reset_point
);
3477 message_ended
= END_NOTSTARTED
;
3479 chunking_state
= chunking_offered
? CHUNKING_OFFERED
: CHUNKING_NOT_OFFERED
;
3481 cmd_list
[CMD_LIST_RSET
].is_mail_cmd
= TRUE
;
3482 cmd_list
[CMD_LIST_HELO
].is_mail_cmd
= TRUE
;
3483 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= TRUE
;
3485 cmd_list
[CMD_LIST_STARTTLS
].is_mail_cmd
= TRUE
;
3486 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= TRUE
;
3489 /* Set the local signal handler for SIGTERM - it tries to end off tidily */
3491 os_non_restarting_signal(SIGTERM
, command_sigterm_handler
);
3493 /* Batched SMTP is handled in a different function. */
3495 if (smtp_batched_input
) return smtp_setup_batch_msg();
3497 /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE
3498 value. The values are 2 larger than the required yield of the function. */
3502 const uschar
**argv
;
3503 uschar
*etrn_command
;
3504 uschar
*etrn_serialize_key
;
3506 uschar
*log_msg
, *smtp_code
;
3507 uschar
*user_msg
= NULL
;
3508 uschar
*recipient
= NULL
;
3509 uschar
*hello
= NULL
;
3511 BOOL was_rej_mail
= FALSE
;
3512 BOOL was_rcpt
= FALSE
;
3513 void (*oldsignal
)(int);
3515 int start
, end
, sender_domain
, recipient_domain
;
3519 uschar
*orcpt
= NULL
;
3522 #if defined(SUPPORT_TLS) && defined(AUTH_TLS)
3523 /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */
3524 if ( tls_in
.active
>= 0
3526 && tls_in
.certificate_verified
3527 && cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
3530 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= FALSE
;
3532 && (rc
= acl_check(ACL_WHERE_AUTH
, NULL
, acl_smtp_auth
,
3533 &user_msg
, &log_msg
)) != OK
3536 done
= smtp_handle_acl_fail(ACL_WHERE_AUTH
, rc
, user_msg
, log_msg
);
3540 for (au
= auths
; au
; au
= au
->next
)
3541 if (strcmpic(US
"tls", au
->driver_name
) == 0)
3543 smtp_cmd_data
= NULL
;
3545 if (smtp_in_auth(au
, &s
, &ss
) == OK
)
3546 { DEBUG(D_auth
) debug_printf("tls auth succeeded\n"); }
3548 { DEBUG(D_auth
) debug_printf("tls auth not succeeded\n"); }
3554 switch(smtp_read_command(TRUE
))
3556 /* The AUTH command is not permitted to occur inside a transaction, and may
3557 occur successfully only once per connection. Actually, that isn't quite
3558 true. When TLS is started, all previous information about a connection must
3559 be discarded, so a new AUTH is permitted at that time.
3561 AUTH may only be used when it has been advertised. However, it seems that
3562 there are clients that send AUTH when it hasn't been advertised, some of
3563 them even doing this after HELO. And there are MTAs that accept this. Sigh.
3564 So there's a get-out that allows this to happen.
3566 AUTH is initially labelled as a "nonmail command" so that one occurrence
3567 doesn't get counted. We change the label here so that multiple failing
3568 AUTHS will eventually hit the nonmail threshold. */
3572 authentication_failed
= TRUE
;
3573 cmd_list
[CMD_LIST_AUTH
].is_mail_cmd
= FALSE
;
3575 if (!auth_advertised
&& !allow_auth_unadvertised
)
3577 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3578 US
"AUTH command used when not advertised");
3581 if (sender_host_authenticated
)
3583 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3584 US
"already authenticated");
3589 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
3590 US
"not permitted in mail transaction");
3597 && (rc
= acl_check(ACL_WHERE_AUTH
, NULL
, acl_smtp_auth
,
3598 &user_msg
, &log_msg
)) != OK
3601 done
= smtp_handle_acl_fail(ACL_WHERE_AUTH
, rc
, user_msg
, log_msg
);
3605 /* Find the name of the requested authentication mechanism. */
3608 while ((c
= *smtp_cmd_data
) != 0 && !isspace(c
))
3610 if (!isalnum(c
) && c
!= '-' && c
!= '_')
3612 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
3613 US
"invalid character in authentication mechanism name");
3619 /* If not at the end of the line, we must be at white space. Terminate the
3620 name and move the pointer on to any data that may be present. */
3622 if (*smtp_cmd_data
!= 0)
3624 *smtp_cmd_data
++ = 0;
3625 while (isspace(*smtp_cmd_data
)) smtp_cmd_data
++;
3628 /* Search for an authentication mechanism which is configured for use
3629 as a server and which has been advertised (unless, sigh, allow_auth_
3630 unadvertised is set). */
3632 for (au
= auths
; au
; au
= au
->next
)
3633 if (strcmpic(s
, au
->public_name
) == 0 && au
->server
&&
3634 (au
->advertised
|| allow_auth_unadvertised
))
3639 c
= smtp_in_auth(au
, &s
, &ss
);
3641 smtp_printf("%s\r\n", s
);
3643 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s authenticator failed for %s: %s",
3644 au
->name
, host_and_ident(FALSE
), ss
);
3647 done
= synprot_error(L_smtp_protocol_error
, 504, NULL
,
3648 string_sprintf("%s authentication mechanism not supported", s
));
3650 break; /* AUTH_CMD */
3652 /* The HELO/EHLO commands are permitted to appear in the middle of a
3653 session as well as at the beginning. They have the effect of a reset in
3654 addition to their other functions. Their absence at the start cannot be
3655 taken to be an error.
3659 If the EHLO command is not acceptable to the SMTP server, 501, 500,
3660 or 502 failure replies MUST be returned as appropriate. The SMTP
3661 server MUST stay in the same state after transmitting these replies
3662 that it was in before the EHLO was received.
3664 Therefore, we do not do the reset until after checking the command for
3665 acceptability. This change was made for Exim release 4.11. Previously
3666 it did the reset first. */
3679 HELO_EHLO
: /* Common code for HELO and EHLO */
3680 cmd_list
[CMD_LIST_HELO
].is_mail_cmd
= FALSE
;
3681 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= FALSE
;
3683 /* Reject the HELO if its argument was invalid or non-existent. A
3684 successful check causes the argument to be saved in malloc store. */
3686 if (!check_helo(smtp_cmd_data
))
3688 smtp_printf("501 Syntactically invalid %s argument(s)\r\n", hello
);
3690 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected %s from %s: syntactically "
3691 "invalid argument(s): %s", hello
, host_and_ident(FALSE
),
3692 (*smtp_cmd_argument
== 0)? US
"(no argument given)" :
3693 string_printing(smtp_cmd_argument
));
3695 if (++synprot_error_count
> smtp_max_synprot_errors
)
3697 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
3698 "syntax or protocol errors (last command was \"%s\")",
3699 host_and_ident(FALSE
), string_printing(smtp_cmd_buffer
));
3706 /* If sender_host_unknown is true, we have got here via the -bs interface,
3707 not called from inetd. Otherwise, we are running an IP connection and the
3708 host address will be set. If the helo name is the primary name of this
3709 host and we haven't done a reverse lookup, force one now. If helo_required
3710 is set, ensure that the HELO name matches the actual host. If helo_verify
3711 is set, do the same check, but softly. */
3713 if (!sender_host_unknown
)
3715 BOOL old_helo_verified
= helo_verified
;
3716 uschar
*p
= smtp_cmd_data
;
3718 while (*p
!= 0 && !isspace(*p
)) { *p
= tolower(*p
); p
++; }
3721 /* Force a reverse lookup if HELO quoted something in helo_lookup_domains
3722 because otherwise the log can be confusing. */
3724 if (sender_host_name
== NULL
&&
3725 (deliver_domain
= sender_helo_name
, /* set $domain */
3726 match_isinlist(sender_helo_name
, CUSS
&helo_lookup_domains
, 0,
3727 &domainlist_anchor
, NULL
, MCL_DOMAIN
, TRUE
, NULL
)) == OK
)
3728 (void)host_name_lookup();
3730 /* Rebuild the fullhost info to include the HELO name (and the real name
3731 if it was looked up.) */
3733 host_build_sender_fullhost(); /* Rebuild */
3734 set_process_info("handling%s incoming connection from %s",
3735 (tls_in
.active
>= 0)? " TLS" : "", host_and_ident(FALSE
));
3737 /* Verify if configured. This doesn't give much security, but it does
3738 make some people happy to be able to do it. If helo_required is set,
3739 (host matches helo_verify_hosts) failure forces rejection. If helo_verify
3740 is set (host matches helo_try_verify_hosts), it does not. This is perhaps
3741 now obsolescent, since the verification can now be requested selectively
3744 helo_verified
= helo_verify_failed
= sender_helo_dnssec
= FALSE
;
3745 if (helo_required
|| helo_verify
)
3747 BOOL tempfail
= !smtp_verify_helo();
3752 smtp_printf("%d %s argument does not match calling host\r\n",
3753 tempfail
? 451 : 550, hello
);
3754 log_write(0, LOG_MAIN
|LOG_REJECT
, "%srejected \"%s %s\" from %s",
3755 tempfail
? "temporarily " : "",
3756 hello
, sender_helo_name
, host_and_ident(FALSE
));
3757 helo_verified
= old_helo_verified
;
3758 break; /* End of HELO/EHLO processing */
3760 HDEBUG(D_all
) debug_printf("%s verification failed but host is in "
3761 "helo_try_verify_hosts\n", hello
);
3766 #ifdef EXPERIMENTAL_SPF
3767 /* set up SPF context */
3768 spf_init(sender_helo_name
, sender_host_address
);
3771 /* Apply an ACL check if one is defined; afterwards, recheck
3772 synchronization in case the client started sending in a delay. */
3775 if ((rc
= acl_check(ACL_WHERE_HELO
, NULL
, acl_smtp_helo
,
3776 &user_msg
, &log_msg
)) != OK
)
3778 done
= smtp_handle_acl_fail(ACL_WHERE_HELO
, rc
, user_msg
, log_msg
);
3779 sender_helo_name
= NULL
;
3780 host_build_sender_fullhost(); /* Rebuild */
3783 else if (!check_sync()) goto SYNC_FAILURE
;
3785 /* Generate an OK reply. The default string includes the ident if present,
3786 and also the IP address if present. Reflecting back the ident is intended
3787 as a deterrent to mail forgers. For maximum efficiency, and also because
3788 some broken systems expect each response to be in a single packet, arrange
3789 that the entire reply is sent in one write(). */
3791 auth_advertised
= FALSE
;
3792 pipelining_advertised
= FALSE
;
3794 tls_advertised
= FALSE
;
3796 dsn_advertised
= FALSE
;
3798 smtputf8_advertised
= FALSE
;
3801 smtp_code
= US
"250 "; /* Default response code plus space*/
3802 if (user_msg
== NULL
)
3804 s
= string_sprintf("%.3s %s Hello %s%s%s",
3806 smtp_active_hostname
,
3807 (sender_ident
== NULL
)? US
"" : sender_ident
,
3808 (sender_ident
== NULL
)? US
"" : US
" at ",
3809 (sender_host_name
== NULL
)? sender_helo_name
: sender_host_name
);
3814 if (sender_host_address
!= NULL
)
3816 s
= string_catn(s
, &size
, &ptr
, US
" [", 2);
3817 s
= string_cat (s
, &size
, &ptr
, sender_host_address
);
3818 s
= string_catn(s
, &size
, &ptr
, US
"]", 1);
3822 /* A user-supplied EHLO greeting may not contain more than one line. Note
3823 that the code returned by smtp_message_code() includes the terminating
3824 whitespace character. */
3830 smtp_message_code(&smtp_code
, &codelen
, &user_msg
, NULL
, TRUE
);
3831 s
= string_sprintf("%.*s%s", codelen
, smtp_code
, user_msg
);
3832 if ((ss
= strpbrk(CS s
, "\r\n")) != NULL
)
3834 log_write(0, LOG_MAIN
|LOG_PANIC
, "EHLO/HELO response must not contain "
3835 "newlines: message truncated: %s", string_printing(s
));
3842 s
= string_catn(s
, &size
, &ptr
, US
"\r\n", 2);
3844 /* If we received EHLO, we must create a multiline response which includes
3845 the functions supported. */
3851 /* I'm not entirely happy with this, as an MTA is supposed to check
3852 that it has enough room to accept a message of maximum size before
3853 it sends this. However, there seems little point in not sending it.
3854 The actual size check happens later at MAIL FROM time. By postponing it
3855 till then, VRFY and EXPN can be used after EHLO when space is short. */
3857 if (thismessage_size_limit
> 0)
3859 sprintf(CS big_buffer
, "%.3s-SIZE %d\r\n", smtp_code
,
3860 thismessage_size_limit
);
3861 s
= string_cat(s
, &size
, &ptr
, big_buffer
);
3865 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3866 s
= string_catn(s
, &size
, &ptr
, US
"-SIZE\r\n", 7);
3869 /* Exim does not do protocol conversion or data conversion. It is 8-bit
3870 clean; if it has an 8-bit character in its hand, it just sends it. It
3871 cannot therefore specify 8BITMIME and remain consistent with the RFCs.
3872 However, some users want this option simply in order to stop MUAs
3873 mangling messages that contain top-bit-set characters. It is therefore
3874 provided as an option. */
3876 if (accept_8bitmime
)
3878 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3879 s
= string_catn(s
, &size
, &ptr
, US
"-8BITMIME\r\n", 11);
3882 /* Advertise DSN support if configured to do so. */
3883 if (verify_check_host(&dsn_advertise_hosts
) != FAIL
)
3885 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3886 s
= string_catn(s
, &size
, &ptr
, US
"-DSN\r\n", 6);
3887 dsn_advertised
= TRUE
;
3890 /* Advertise ETRN if there's an ACL checking whether a host is
3891 permitted to issue it; a check is made when any host actually tries. */
3893 if (acl_smtp_etrn
!= NULL
)
3895 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3896 s
= string_catn(s
, &size
, &ptr
, US
"-ETRN\r\n", 7);
3899 /* Advertise EXPN if there's an ACL checking whether a host is
3900 permitted to issue it; a check is made when any host actually tries. */
3902 if (acl_smtp_expn
!= NULL
)
3904 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3905 s
= string_catn(s
, &size
, &ptr
, US
"-EXPN\r\n", 7);
3908 /* Exim is quite happy with pipelining, so let the other end know that
3909 it is safe to use it, unless advertising is disabled. */
3911 if (pipelining_enable
&&
3912 verify_check_host(&pipelining_advertise_hosts
) == OK
)
3914 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3915 s
= string_catn(s
, &size
, &ptr
, US
"-PIPELINING\r\n", 13);
3916 sync_cmd_limit
= NON_SYNC_CMD_PIPELINING
;
3917 pipelining_advertised
= TRUE
;
3921 /* If any server authentication mechanisms are configured, advertise
3922 them if the current host is in auth_advertise_hosts. The problem with
3923 advertising always is that some clients then require users to
3924 authenticate (and aren't configurable otherwise) even though it may not
3925 be necessary (e.g. if the host is in host_accept_relay).
3927 RFC 2222 states that SASL mechanism names contain only upper case
3928 letters, so output the names in upper case, though we actually recognize
3929 them in either case in the AUTH command. */
3932 #if defined(SUPPORT_TLS) && defined(AUTH_TLS)
3933 && !sender_host_authenticated
3935 && verify_check_host(&auth_advertise_hosts
) == OK
3940 for (au
= auths
; au
; au
= au
->next
)
3941 if (au
->server
&& (au
->advertise_condition
== NULL
||
3942 expand_check_condition(au
->advertise_condition
, au
->name
,
3943 US
"authenticator")))
3948 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3949 s
= string_catn(s
, &size
, &ptr
, US
"-AUTH", 5);
3951 auth_advertised
= TRUE
;
3954 s
= string_catn(s
, &size
, &ptr
, US
" ", 1);
3955 s
= string_cat (s
, &size
, &ptr
, au
->public_name
);
3956 while (++saveptr
< ptr
) s
[saveptr
] = toupper(s
[saveptr
]);
3957 au
->advertised
= TRUE
;
3960 au
->advertised
= FALSE
;
3962 if (!first
) s
= string_catn(s
, &size
, &ptr
, US
"\r\n", 2);
3965 /* RFC 3030 CHUNKING */
3967 if (verify_check_host(&chunking_advertise_hosts
) != FAIL
)
3969 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3970 s
= string_catn(s
, &size
, &ptr
, US
"-CHUNKING\r\n", 11);
3971 chunking_offered
= TRUE
;
3972 chunking_state
= CHUNKING_OFFERED
;
3975 /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
3976 if it has been included in the binary, and the host matches
3977 tls_advertise_hosts. We must *not* advertise if we are already in a
3978 secure connection. */
3981 if (tls_in
.active
< 0 &&
3982 verify_check_host(&tls_advertise_hosts
) != FAIL
)
3984 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3985 s
= string_catn(s
, &size
, &ptr
, US
"-STARTTLS\r\n", 11);
3986 tls_advertised
= TRUE
;
3990 #ifndef DISABLE_PRDR
3991 /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */
3994 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
3995 s
= string_catn(s
, &size
, &ptr
, US
"-PRDR\r\n", 7);
4000 if ( accept_8bitmime
4001 && verify_check_host(&smtputf8_advertise_hosts
) != FAIL
)
4003 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
4004 s
= string_catn(s
, &size
, &ptr
, US
"-SMTPUTF8\r\n", 11);
4005 smtputf8_advertised
= TRUE
;
4009 /* Finish off the multiline reply with one that is always available. */
4011 s
= string_catn(s
, &size
, &ptr
, smtp_code
, 3);
4012 s
= string_catn(s
, &size
, &ptr
, US
" HELP\r\n", 7);
4015 /* Terminate the string (for debug), write it, and note that HELO/EHLO
4021 if (tls_in
.active
>= 0) (void)tls_write(TRUE
, s
, ptr
); else
4025 int i
= fwrite(s
, 1, ptr
, smtp_out
); i
= i
; /* compiler quietening */
4030 while ((cr
= Ustrchr(s
, '\r')) != NULL
) /* lose CRs */
4031 memmove(cr
, cr
+ 1, (ptr
--) - (cr
- s
));
4032 debug_printf("SMTP>> %s", s
);
4036 /* Reset the protocol and the state, abandoning any previous message. */
4038 (sender_host_address
? protocols
: protocols_local
)
4040 ? pextend
+ (sender_host_authenticated
? pauthed
: 0)
4042 + (tls_in
.active
>= 0 ? pcrpted
: 0)
4044 smtp_reset(reset_point
);
4046 break; /* HELO/EHLO */
4049 /* The MAIL command requires an address as an operand. All we do
4050 here is to parse it for syntactic correctness. The form "<>" is
4051 a special case which converts into an empty string. The start/end
4052 pointers in the original are not used further for this address, as
4053 it is the canonical extracted address which is all that is kept. */
4057 smtp_mailcmd_count
++; /* Count for limit and ratelimit */
4058 was_rej_mail
= TRUE
; /* Reset if accepted */
4059 env_mail_type_t
* mail_args
; /* Sanity check & validate args */
4061 if (helo_required
&& !helo_seen
)
4063 smtp_printf("503 HELO or EHLO required\r\n");
4064 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected MAIL from %s: no "
4065 "HELO/EHLO given", host_and_ident(FALSE
));
4069 if (sender_address
!= NULL
)
4071 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4072 US
"sender already given");
4076 if (smtp_cmd_data
[0] == 0)
4078 done
= synprot_error(L_smtp_protocol_error
, 501, NULL
,
4079 US
"MAIL must have an address operand");
4083 /* Check to see if the limit for messages per connection would be
4084 exceeded by accepting further messages. */
4086 if (smtp_accept_max_per_connection
> 0 &&
4087 smtp_mailcmd_count
> smtp_accept_max_per_connection
)
4089 smtp_printf("421 too many messages in this connection\r\n");
4090 log_write(0, LOG_MAIN
|LOG_REJECT
, "rejected MAIL command %s: too many "
4091 "messages in one connection", host_and_ident(TRUE
));
4095 /* Reset for start of message - even if this is going to fail, we
4096 obviously need to throw away any previous data. */
4098 smtp_reset(reset_point
);
4100 sender_data
= recipient_data
= NULL
;
4102 /* Loop, checking for ESMTP additions to the MAIL FROM command. */
4106 uschar
*name
, *value
, *end
;
4107 unsigned long int size
;
4108 BOOL arg_error
= FALSE
;
4110 if (!extract_option(&name
, &value
)) break;
4112 for (mail_args
= env_mail_type_list
;
4113 mail_args
->value
!= ENV_MAIL_OPT_NULL
;
4116 if (strcmpic(name
, mail_args
->name
) == 0)
4118 if (mail_args
->need_value
&& strcmpic(value
, US
"") == 0)
4121 switch(mail_args
->value
)
4123 /* Handle SIZE= by reading the value. We don't do the check till later,
4124 in order to be able to log the sender address on failure. */
4125 case ENV_MAIL_OPT_SIZE
:
4126 if (((size
= Ustrtoul(value
, &end
, 10)), *end
== 0))
4128 if ((size
== ULONG_MAX
&& errno
== ERANGE
) || size
> INT_MAX
)
4130 message_size
= (int)size
;
4136 /* If this session was initiated with EHLO and accept_8bitmime is set,
4137 Exim will have indicated that it supports the BODY=8BITMIME option. In
4138 fact, it does not support this according to the RFCs, in that it does not
4139 take any special action for forwarding messages containing 8-bit
4140 characters. That is why accept_8bitmime is not the default setting, but
4141 some sites want the action that is provided. We recognize both "8BITMIME"
4142 and "7BIT" as body types, but take no action. */
4143 case ENV_MAIL_OPT_BODY
:
4144 if (accept_8bitmime
) {
4145 if (strcmpic(value
, US
"8BITMIME") == 0)
4147 else if (strcmpic(value
, US
"7BIT") == 0)
4152 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4153 US
"invalid data for BODY");
4156 DEBUG(D_receive
) debug_printf("8BITMIME: %d\n", body_8bitmime
);
4162 /* Handle the two DSN options, but only if configured to do so (which
4163 will have caused "DSN" to be given in the EHLO response). The code itself
4164 is included only if configured in at build time. */
4166 case ENV_MAIL_OPT_RET
:
4169 /* Check if RET has already been set */
4172 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4173 US
"RET can be specified once only");
4176 dsn_ret
= strcmpic(value
, US
"HDRS") == 0
4178 : strcmpic(value
, US
"FULL") == 0
4181 DEBUG(D_receive
) debug_printf("DSN_RET: %d\n", dsn_ret
);
4182 /* Check for invalid invalid value, and exit with error */
4185 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4186 US
"Value for RET is invalid");
4191 case ENV_MAIL_OPT_ENVID
:
4194 /* Check if the dsn envid has been already set */
4195 if (dsn_envid
!= NULL
)
4197 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4198 US
"ENVID can be specified once only");
4201 dsn_envid
= string_copy(value
);
4202 DEBUG(D_receive
) debug_printf("DSN_ENVID: %s\n", dsn_envid
);
4206 /* Handle the AUTH extension. If the value given is not "<>" and either
4207 the ACL says "yes" or there is no ACL but the sending host is
4208 authenticated, we set it up as the authenticated sender. However, if the
4209 authenticator set a condition to be tested, we ignore AUTH on MAIL unless
4210 the condition is met. The value of AUTH is an xtext, which means that +,
4211 = and cntrl chars are coded in hex; however "<>" is unaffected by this
4213 case ENV_MAIL_OPT_AUTH
:
4214 if (Ustrcmp(value
, "<>") != 0)
4219 if (auth_xtextdecode(value
, &authenticated_sender
) < 0)
4221 /* Put back terminator overrides for error message */
4224 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4225 US
"invalid data for AUTH");
4228 if (acl_smtp_mailauth
== NULL
)
4230 ignore_msg
= US
"client not authenticated";
4231 rc
= (sender_host_authenticated
!= NULL
)? OK
: FAIL
;
4235 ignore_msg
= US
"rejected by ACL";
4236 rc
= acl_check(ACL_WHERE_MAILAUTH
, NULL
, acl_smtp_mailauth
,
4237 &user_msg
, &log_msg
);
4243 if (authenticated_by
== NULL
||
4244 authenticated_by
->mail_auth_condition
== NULL
||
4245 expand_check_condition(authenticated_by
->mail_auth_condition
,
4246 authenticated_by
->name
, US
"authenticator"))
4247 break; /* Accept the AUTH */
4249 ignore_msg
= US
"server_mail_auth_condition failed";
4250 if (authenticated_id
!= NULL
)
4251 ignore_msg
= string_sprintf("%s: authenticated ID=\"%s\"",
4252 ignore_msg
, authenticated_id
);
4257 authenticated_sender
= NULL
;
4258 log_write(0, LOG_MAIN
, "ignoring AUTH=%s from %s (%s)",
4259 value
, host_and_ident(TRUE
), ignore_msg
);
4262 /* Should only get DEFER or ERROR here. Put back terminator
4263 overrides for error message */
4268 (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH
, rc
, user_msg
,
4275 #ifndef DISABLE_PRDR
4276 case ENV_MAIL_OPT_PRDR
:
4278 prdr_requested
= TRUE
;
4283 case ENV_MAIL_OPT_UTF8
:
4284 if (smtputf8_advertised
)
4286 DEBUG(D_receive
) debug_printf("smtputf8 requested\n");
4287 message_smtputf8
= allow_utf8_domains
= TRUE
;
4288 received_protocol
= string_sprintf("utf8%s", received_protocol
);
4292 /* No valid option. Stick back the terminator characters and break
4293 the loop. Do the name-terminator second as extract_option sets
4294 value==name when it found no equal-sign.
4295 An error for a malformed address will occur. */
4296 case ENV_MAIL_OPT_NULL
:
4304 /* Break out of for loop if switch() had bad argument or
4305 when start of the email address is reached */
4306 if (arg_error
) break;
4309 /* If we have passed the threshold for rate limiting, apply the current
4310 delay, and update it for next time, provided this is a limited host. */
4312 if (smtp_mailcmd_count
> smtp_rlm_threshold
&&
4313 verify_check_host(&smtp_ratelimit_hosts
) == OK
)
4315 DEBUG(D_receive
) debug_printf("rate limit MAIL: delay %.3g sec\n",
4316 smtp_delay_mail
/1000.0);
4317 millisleep((int)smtp_delay_mail
);
4318 smtp_delay_mail
*= smtp_rlm_factor
;
4319 if (smtp_delay_mail
> (double)smtp_rlm_limit
)
4320 smtp_delay_mail
= (double)smtp_rlm_limit
;
4323 /* Now extract the address, first applying any SMTP-time rewriting. The
4324 TRUE flag allows "<>" as a sender address. */
4326 raw_sender
= rewrite_existflags
& rewrite_smtp
4327 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
4328 global_rewrite_rules
)
4332 parse_extract_address(raw_sender
, &errmess
, &start
, &end
, &sender_domain
,
4337 done
= synprot_error(L_smtp_syntax_error
, 501, smtp_cmd_data
, errmess
);
4341 sender_address
= raw_sender
;
4343 /* If there is a configured size limit for mail, check that this message
4344 doesn't exceed it. The check is postponed to this point so that the sender
4347 if (thismessage_size_limit
> 0 && message_size
> thismessage_size_limit
)
4349 smtp_printf("552 Message size exceeds maximum permitted\r\n");
4350 log_write(L_size_reject
,
4351 LOG_MAIN
|LOG_REJECT
, "rejected MAIL FROM:<%s> %s: "
4352 "message too big: size%s=%d max=%d",
4354 host_and_ident(TRUE
),
4355 (message_size
== INT_MAX
)? ">" : "",
4357 thismessage_size_limit
);
4358 sender_address
= NULL
;
4362 /* Check there is enough space on the disk unless configured not to.
4363 When smtp_check_spool_space is set, the check is for thismessage_size_limit
4364 plus the current message - i.e. we accept the message only if it won't
4365 reduce the space below the threshold. Add 5000 to the size to allow for
4366 overheads such as the Received: line and storing of recipients, etc.
4367 By putting the check here, even when SIZE is not given, it allow VRFY
4368 and EXPN etc. to be used when space is short. */
4370 if (!receive_check_fs(
4371 (smtp_check_spool_space
&& message_size
>= 0)?
4372 message_size
+ 5000 : 0))
4374 smtp_printf("452 Space shortage, please try later\r\n");
4375 sender_address
= NULL
;
4379 /* If sender_address is unqualified, reject it, unless this is a locally
4380 generated message, or the sending host or net is permitted to send
4381 unqualified addresses - typically local machines behaving as MUAs -
4382 in which case just qualify the address. The flag is set above at the start
4383 of the SMTP connection. */
4385 if (sender_domain
== 0 && sender_address
[0] != 0)
4387 if (allow_unqualified_sender
)
4389 sender_domain
= Ustrlen(sender_address
) + 1;
4390 sender_address
= rewrite_address_qualify(sender_address
, FALSE
);
4391 DEBUG(D_receive
) debug_printf("unqualified address %s accepted\n",
4396 smtp_printf("501 %s: sender address must contain a domain\r\n",
4398 log_write(L_smtp_syntax_error
,
4399 LOG_MAIN
|LOG_REJECT
,
4400 "unqualified sender rejected: <%s> %s%s",
4402 host_and_ident(TRUE
),
4404 sender_address
= NULL
;
4409 /* Apply an ACL check if one is defined, before responding. Afterwards,
4410 when pipelining is not advertised, do another sync check in case the ACL
4411 delayed and the client started sending in the meantime. */
4415 rc
= acl_check(ACL_WHERE_MAIL
, NULL
, acl_smtp_mail
, &user_msg
, &log_msg
);
4416 if (rc
== OK
&& !pipelining_advertised
&& !check_sync())
4422 if (rc
== OK
|| rc
== DISCARD
)
4425 smtp_printf("%s%s%s", US
"250 OK",
4426 #ifndef DISABLE_PRDR
4427 prdr_requested
? US
", PRDR Requested" : US
"",
4434 #ifndef DISABLE_PRDR
4436 user_msg
= string_sprintf("%s%s", user_msg
, US
", PRDR Requested");
4438 smtp_user_msg(US
"250", user_msg
);
4440 smtp_delay_rcpt
= smtp_rlr_base
;
4441 recipients_discarded
= (rc
== DISCARD
);
4442 was_rej_mail
= FALSE
;
4446 done
= smtp_handle_acl_fail(ACL_WHERE_MAIL
, rc
, user_msg
, log_msg
);
4447 sender_address
= NULL
;
4452 /* The RCPT command requires an address as an operand. There may be any
4453 number of RCPT commands, specifying multiple recipients. We build them all
4454 into a data structure. The start/end values given by parse_extract_address
4455 are not used, as we keep only the extracted address. */
4460 was_rcpt
= rcpt_in_progress
= TRUE
;
4462 /* There must be a sender address; if the sender was rejected and
4463 pipelining was advertised, we assume the client was pipelining, and do not
4464 count this as a protocol error. Reset was_rej_mail so that further RCPTs
4465 get the same treatment. */
4467 if (sender_address
== NULL
)
4469 if (pipelining_advertised
&& last_was_rej_mail
)
4471 smtp_printf("503 sender not yet given\r\n");
4472 was_rej_mail
= TRUE
;
4476 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4477 US
"sender not yet given");
4478 was_rcpt
= FALSE
; /* Not a valid RCPT */
4484 /* Check for an operand */
4486 if (smtp_cmd_data
[0] == 0)
4488 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
4489 US
"RCPT must have an address operand");
4494 /* Set the DSN flags orcpt and dsn_flags from the session*/
4500 uschar
*name
, *value
;
4502 if (!extract_option(&name
, &value
))
4505 if (dsn_advertised
&& strcmpic(name
, US
"ORCPT") == 0)
4507 /* Check whether orcpt has been already set */
4510 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4511 US
"ORCPT can be specified once only");
4514 orcpt
= string_copy(value
);
4515 DEBUG(D_receive
) debug_printf("DSN orcpt: %s\n", orcpt
);
4518 else if (dsn_advertised
&& strcmpic(name
, US
"NOTIFY") == 0)
4520 /* Check if the notify flags have been already set */
4523 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4524 US
"NOTIFY can be specified once only");
4527 if (strcmpic(value
, US
"NEVER") == 0)
4528 flags
|= rf_notify_never
;
4535 while (*pp
!= 0 && *pp
!= ',') pp
++;
4536 if (*pp
== ',') *pp
++ = 0;
4537 if (strcmpic(p
, US
"SUCCESS") == 0)
4539 DEBUG(D_receive
) debug_printf("DSN: Setting notify success\n");
4540 flags
|= rf_notify_success
;
4542 else if (strcmpic(p
, US
"FAILURE") == 0)
4544 DEBUG(D_receive
) debug_printf("DSN: Setting notify failure\n");
4545 flags
|= rf_notify_failure
;
4547 else if (strcmpic(p
, US
"DELAY") == 0)
4549 DEBUG(D_receive
) debug_printf("DSN: Setting notify delay\n");
4550 flags
|= rf_notify_delay
;
4554 /* Catch any strange values */
4555 synprot_error(L_smtp_syntax_error
, 501, NULL
,
4556 US
"Invalid value for NOTIFY parameter");
4561 DEBUG(D_receive
) debug_printf("DSN Flags: %x\n", flags
);
4565 /* Unknown option. Stick back the terminator characters and break
4566 the loop. An error for a malformed address will occur. */
4570 DEBUG(D_receive
) debug_printf("Invalid RCPT option: %s : %s\n", name
, value
);
4577 /* Apply SMTP rewriting then extract the working address. Don't allow "<>"
4578 as a recipient address */
4580 recipient
= rewrite_existflags
& rewrite_smtp
4581 ? rewrite_one(smtp_cmd_data
, rewrite_smtp
, NULL
, FALSE
, US
"",
4582 global_rewrite_rules
)
4585 if (!(recipient
= parse_extract_address(recipient
, &errmess
, &start
, &end
,
4586 &recipient_domain
, FALSE
)))
4588 done
= synprot_error(L_smtp_syntax_error
, 501, smtp_cmd_data
, errmess
);
4593 /* If the recipient address is unqualified, reject it, unless this is a
4594 locally generated message. However, unqualified addresses are permitted
4595 from a configured list of hosts and nets - typically when behaving as
4596 MUAs rather than MTAs. Sad that SMTP is used for both types of traffic,
4597 really. The flag is set at the start of the SMTP connection.
4599 RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always
4600 assumed this meant "reserved local part", but the revision of RFC 821 and
4601 friends now makes it absolutely clear that it means *mailbox*. Consequently
4602 we must always qualify this address, regardless. */
4604 if (recipient_domain
== 0)
4605 if (!(recipient_domain
= qualify_recipient(&recipient
, smtp_cmd_data
,
4612 /* Check maximum allowed */
4614 if (rcpt_count
> recipients_max
&& recipients_max
> 0)
4616 if (recipients_max_reject
)
4619 smtp_printf("552 too many recipients\r\n");
4621 log_write(0, LOG_MAIN
|LOG_REJECT
, "too many recipients: message "
4622 "rejected: sender=<%s> %s", sender_address
, host_and_ident(TRUE
));
4627 smtp_printf("452 too many recipients\r\n");
4629 log_write(0, LOG_MAIN
|LOG_REJECT
, "too many recipients: excess "
4630 "temporarily rejected: sender=<%s> %s", sender_address
,
4631 host_and_ident(TRUE
));
4638 /* If we have passed the threshold for rate limiting, apply the current
4639 delay, and update it for next time, provided this is a limited host. */
4641 if (rcpt_count
> smtp_rlr_threshold
&&
4642 verify_check_host(&smtp_ratelimit_hosts
) == OK
)
4644 DEBUG(D_receive
) debug_printf("rate limit RCPT: delay %.3g sec\n",
4645 smtp_delay_rcpt
/1000.0);
4646 millisleep((int)smtp_delay_rcpt
);
4647 smtp_delay_rcpt
*= smtp_rlr_factor
;
4648 if (smtp_delay_rcpt
> (double)smtp_rlr_limit
)
4649 smtp_delay_rcpt
= (double)smtp_rlr_limit
;
4652 /* If the MAIL ACL discarded all the recipients, we bypass ACL checking
4653 for them. Otherwise, check the access control list for this recipient. As
4654 there may be a delay in this, re-check for a synchronization error
4655 afterwards, unless pipelining was advertised. */
4657 if (recipients_discarded
) rc
= DISCARD
; else
4659 rc
= acl_check(ACL_WHERE_RCPT
, recipient
, acl_smtp_rcpt
, &user_msg
,
4661 if (rc
== OK
&& !pipelining_advertised
&& !check_sync())
4665 /* The ACL was happy */
4669 if (user_msg
== NULL
) smtp_printf("250 Accepted\r\n");
4670 else smtp_user_msg(US
"250", user_msg
);
4671 receive_add_recipient(recipient
, -1);
4673 /* Set the dsn flags in the recipients_list */
4674 recipients_list
[recipients_count
-1].orcpt
= orcpt
;
4675 recipients_list
[recipients_count
-1].dsn_flags
= flags
;
4677 DEBUG(D_receive
) debug_printf("DSN: orcpt: %s flags: %d\n",
4678 recipients_list
[recipients_count
-1].orcpt
,
4679 recipients_list
[recipients_count
-1].dsn_flags
);
4682 /* The recipient was discarded */
4684 else if (rc
== DISCARD
)
4686 if (user_msg
== NULL
) smtp_printf("250 Accepted\r\n");
4687 else smtp_user_msg(US
"250", user_msg
);
4690 log_write(0, LOG_MAIN
|LOG_REJECT
, "%s F=<%s> RCPT %s: "
4691 "discarded by %s ACL%s%s", host_and_ident(TRUE
),
4692 sender_address_unrewritten
? sender_address_unrewritten
: sender_address
,
4693 smtp_cmd_argument
, recipients_discarded
? "MAIL" : "RCPT",
4694 log_msg
? US
": " : US
"", log_msg
? log_msg
: US
"");
4697 /* Either the ACL failed the address, or it was deferred. */
4701 if (rc
== FAIL
) rcpt_fail_count
++; else rcpt_defer_count
++;
4702 done
= smtp_handle_acl_fail(ACL_WHERE_RCPT
, rc
, user_msg
, log_msg
);
4707 /* The DATA command is legal only if it follows successful MAIL FROM
4708 and RCPT TO commands. However, if pipelining is advertised, a bad DATA is
4709 not counted as a protocol error if it follows RCPT (which must have been
4710 rejected if there are no recipients.) This function is complete when a
4711 valid DATA command is encountered.
4713 Note concerning the code used: RFC 2821 says this:
4715 - If there was no MAIL, or no RCPT, command, or all such commands
4716 were rejected, the server MAY return a "command out of sequence"
4717 (503) or "no valid recipients" (554) reply in response to the
4720 The example in the pipelining RFC 2920 uses 554, but I use 503 here
4721 because it is the same whether pipelining is in use or not.
4723 If all the RCPT commands that precede DATA provoked the same error message
4724 (often indicating some kind of system error), it is helpful to include it
4725 with the DATA rejection (an idea suggested by Tony Finch). */
4732 if (chunking_state
!= CHUNKING_OFFERED
)
4734 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4735 US
"BDAT command used when CHUNKING not advertised");
4739 /* grab size, endmarker */
4741 if (sscanf(CS smtp_cmd_data
, "%u %n", &chunking_datasize
, &n
) < 1)
4743 done
= synprot_error(L_smtp_protocol_error
, 501, NULL
,
4744 US
"missing size for BDAT command");
4747 chunking_state
= strcmpic(smtp_cmd_data
+n
, US
"LAST") == 0
4748 ? CHUNKING_LAST
: CHUNKING_ACTIVE
;
4749 chunking_data_left
= chunking_datasize
;
4751 lwr_receive_getc
= receive_getc
;
4752 lwr_receive_ungetc
= receive_ungetc
;
4753 receive_getc
= bdat_getc
;
4754 receive_ungetc
= bdat_ungetc
;
4757 debug_printf("chunking state %d\n", (int)chunking_state
);
4764 DATA_BDAT
: /* Common code for DATA and BDAT */
4765 if (!discarded
&& recipients_count
<= 0)
4767 if (rcpt_smtp_response_same
&& rcpt_smtp_response
!= NULL
)
4769 uschar
*code
= US
"503";
4770 int len
= Ustrlen(rcpt_smtp_response
);
4771 smtp_respond(code
, 3, FALSE
, US
"All RCPT commands were rejected with "
4773 /* Responses from smtp_printf() will have \r\n on the end */
4774 if (len
> 2 && rcpt_smtp_response
[len
-2] == '\r')
4775 rcpt_smtp_response
[len
-2] = 0;
4776 smtp_respond(code
, 3, FALSE
, rcpt_smtp_response
);
4778 if (pipelining_advertised
&& last_was_rcpt
)
4779 smtp_printf("503 Valid RCPT command must precede %s\r\n",
4780 smtp_names
[smtp_connection_had
[smtp_ch_index
-1]]);
4782 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4783 smtp_connection_had
[smtp_ch_index
-1] == SCH_DATA
4784 ? US
"valid RCPT command must precede DATA"
4785 : US
"valid RCPT command must precede BDAT");
4787 if (chunking_state
> CHUNKING_OFFERED
)
4792 if (toomany
&& recipients_max_reject
)
4794 sender_address
= NULL
; /* This will allow a new MAIL without RSET */
4795 sender_address_unrewritten
= NULL
;
4796 smtp_printf("554 Too many recipients\r\n");
4800 if (chunking_state
> CHUNKING_OFFERED
)
4801 { /* No predata ACL or go-ahead output for BDAT */
4806 /* If there is an ACL, re-check the synchronization afterwards, since the
4807 ACL may have delayed. To handle cutthrough delivery enforce a dummy call
4808 to get the DATA command sent. */
4810 if (acl_smtp_predata
== NULL
&& cutthrough
.fd
< 0)
4814 uschar
* acl
= acl_smtp_predata
? acl_smtp_predata
: US
"accept";
4815 enable_dollar_recipients
= TRUE
;
4816 rc
= acl_check(ACL_WHERE_PREDATA
, NULL
, acl
, &user_msg
,
4818 enable_dollar_recipients
= FALSE
;
4819 if (rc
== OK
&& !check_sync())
4823 { /* Either the ACL failed the address, or it was deferred. */
4824 done
= smtp_handle_acl_fail(ACL_WHERE_PREDATA
, rc
, user_msg
, log_msg
);
4830 smtp_user_msg(US
"354", user_msg
);
4833 "354 Enter message, ending with \".\" on a line by itself\r\n");
4837 message_ended
= END_NOTENDED
; /* Indicate in middle of data */
4848 if (!(address
= parse_extract_address(smtp_cmd_data
, &errmess
,
4849 &start
, &end
, &recipient_domain
, FALSE
)))
4851 smtp_printf("501 %s\r\n", errmess
);
4855 if (recipient_domain
== 0)
4856 if (!(recipient_domain
= qualify_recipient(&address
, smtp_cmd_data
,
4860 if ((rc
= acl_check(ACL_WHERE_VRFY
, address
, acl_smtp_vrfy
,
4861 &user_msg
, &log_msg
)) != OK
)
4862 done
= smtp_handle_acl_fail(ACL_WHERE_VRFY
, rc
, user_msg
, log_msg
);
4866 address_item
* addr
= deliver_make_addr(address
, FALSE
);
4868 switch(verify_address(addr
, NULL
, vopt_is_recipient
| vopt_qualify
, -1,
4869 -1, -1, NULL
, NULL
, NULL
))
4872 s
= string_sprintf("250 <%s> is deliverable", address
);
4876 s
= (addr
->user_message
!= NULL
)?
4877 string_sprintf("451 <%s> %s", address
, addr
->user_message
) :
4878 string_sprintf("451 Cannot resolve <%s> at this time", address
);
4882 s
= (addr
->user_message
!= NULL
)?
4883 string_sprintf("550 <%s> %s", address
, addr
->user_message
) :
4884 string_sprintf("550 <%s> is not deliverable", address
);
4885 log_write(0, LOG_MAIN
, "VRFY failed for %s %s",
4886 smtp_cmd_argument
, host_and_ident(TRUE
));
4890 smtp_printf("%s\r\n", s
);
4898 rc
= acl_check(ACL_WHERE_EXPN
, NULL
, acl_smtp_expn
, &user_msg
, &log_msg
);
4900 done
= smtp_handle_acl_fail(ACL_WHERE_EXPN
, rc
, user_msg
, log_msg
);
4903 BOOL save_log_testing_mode
= log_testing_mode
;
4904 address_test_mode
= log_testing_mode
= TRUE
;
4905 (void) verify_address(deliver_make_addr(smtp_cmd_data
, FALSE
),
4906 smtp_out
, vopt_is_recipient
| vopt_qualify
| vopt_expn
, -1, -1, -1,
4908 address_test_mode
= FALSE
;
4909 log_testing_mode
= save_log_testing_mode
; /* true for -bh */
4918 if (!tls_advertised
)
4920 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
4921 US
"STARTTLS command used when not advertised");
4925 /* Apply an ACL check if one is defined */
4927 if ( acl_smtp_starttls
4928 && (rc
= acl_check(ACL_WHERE_STARTTLS
, NULL
, acl_smtp_starttls
,
4929 &user_msg
, &log_msg
)) != OK
4932 done
= smtp_handle_acl_fail(ACL_WHERE_STARTTLS
, rc
, user_msg
, log_msg
);
4936 /* RFC 2487 is not clear on when this command may be sent, though it
4937 does state that all information previously obtained from the client
4938 must be discarded if a TLS session is started. It seems reasonble to
4939 do an implied RSET when STARTTLS is received. */
4941 incomplete_transaction_log(US
"STARTTLS");
4942 smtp_reset(reset_point
);
4944 cmd_list
[CMD_LIST_STARTTLS
].is_mail_cmd
= FALSE
;
4946 /* There's an attack where more data is read in past the STARTTLS command
4947 before TLS is negotiated, then assumed to be part of the secure session
4948 when used afterwards; we use segregated input buffers, so are not
4949 vulnerable, but we want to note when it happens and, for sheer paranoia,
4950 ensure that the buffer is "wiped".
4951 Pipelining sync checks will normally have protected us too, unless disabled
4952 by configuration. */
4954 if (receive_smtp_buffered())
4957 debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n");
4958 if (tls_in
.active
< 0)
4959 smtp_inend
= smtp_inptr
= smtp_inbuffer
;
4960 /* and if TLS is already active, tls_server_start() should fail */
4963 /* There is nothing we value in the input buffer and if TLS is succesfully
4964 negotiated, we won't use this buffer again; if TLS fails, we'll just read
4965 fresh content into it. The buffer contains arbitrary content from an
4966 untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n
4967 It seems safest to just wipe away the content rather than leave it as a
4968 target to jump to. */
4970 memset(smtp_inbuffer
, 0, in_buffer_size
);
4972 /* Attempt to start up a TLS session, and if successful, discard all
4973 knowledge that was obtained previously. At least, that's what the RFC says,
4974 and that's what happens by default. However, in order to work round YAEB,
4975 there is an option to remember the esmtp state. Sigh.
4977 We must allow for an extra EHLO command and an extra AUTH command after
4978 STARTTLS that don't add to the nonmail command count. */
4980 if ((rc
= tls_server_start(tls_require_ciphers
)) == OK
)
4982 if (!tls_remember_esmtp
)
4983 helo_seen
= esmtp
= auth_advertised
= pipelining_advertised
= FALSE
;
4984 cmd_list
[CMD_LIST_EHLO
].is_mail_cmd
= TRUE
;
4985 cmd_list
[CMD_LIST_AUTH
].is_mail_cmd
= TRUE
;
4986 cmd_list
[CMD_LIST_TLS_AUTH
].is_mail_cmd
= TRUE
;
4987 if (sender_helo_name
!= NULL
)
4989 store_free(sender_helo_name
);
4990 sender_helo_name
= NULL
;
4991 host_build_sender_fullhost(); /* Rebuild */
4992 set_process_info("handling incoming TLS connection from %s",
4993 host_and_ident(FALSE
));
4996 (sender_host_address
? protocols
: protocols_local
)
4998 ? pextend
+ (sender_host_authenticated
? pauthed
: 0)
5000 + (tls_in
.active
>= 0 ? pcrpted
: 0)
5003 sender_host_authenticated
= NULL
;
5004 authenticated_id
= NULL
;
5005 sync_cmd_limit
= NON_SYNC_CMD_NON_PIPELINING
;
5006 DEBUG(D_tls
) debug_printf("TLS active\n");
5007 break; /* Successful STARTTLS */
5010 /* Some local configuration problem was discovered before actually trying
5011 to do a TLS handshake; give a temporary error. */
5013 else if (rc
== DEFER
)
5015 smtp_printf("454 TLS currently unavailable\r\n");
5019 /* Hard failure. Reject everything except QUIT or closed connection. One
5020 cause for failure is a nested STARTTLS, in which case tls_in.active remains
5021 set, but we must still reject all incoming commands. */
5023 DEBUG(D_tls
) debug_printf("TLS failed to start\n");
5024 while (done
<= 0) switch(smtp_read_command(FALSE
))
5027 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by EOF",
5028 smtp_get_connection_info());
5029 smtp_notquit_exit(US
"tls-failed", NULL
, NULL
);
5033 /* It is perhaps arguable as to which exit ACL should be called here,
5034 but as it is probably a situation that almost never arises, it
5035 probably doesn't matter. We choose to call the real QUIT ACL, which in
5036 some sense is perhaps "right". */
5041 && ((rc
= acl_check(ACL_WHERE_QUIT
, NULL
, acl_smtp_quit
, &user_msg
,
5042 &log_msg
)) == ERROR
))
5043 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL for QUIT returned ERROR: %s",
5046 smtp_respond(US
"221", 3, TRUE
, user_msg
);
5048 smtp_printf("221 %s closing connection\r\n", smtp_active_hostname
);
5049 log_write(L_smtp_connection
, LOG_MAIN
, "%s closed by QUIT",
5050 smtp_get_connection_info());
5055 smtp_printf("554 Security failure\r\n");
5058 tls_close(TRUE
, TRUE
);
5063 /* The ACL for QUIT is provided for gathering statistical information or
5064 similar; it does not affect the response code, but it can supply a custom
5068 smtp_quit_handler(&user_msg
, &log_msg
);
5074 smtp_rset_handler();
5075 smtp_reset(reset_point
);
5082 smtp_printf("250 OK\r\n");
5086 /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually
5087 used, a check will be done for permitted hosts. Show STARTTLS only if not
5088 already in a TLS session and if it would be advertised in the EHLO
5093 smtp_printf("214-Commands supported:\r\n");
5097 Ustrcat(buffer
, " AUTH");
5099 if (tls_in
.active
< 0 &&
5100 verify_check_host(&tls_advertise_hosts
) != FAIL
)
5101 Ustrcat(buffer
, " STARTTLS");
5103 Ustrcat(buffer
, " HELO EHLO MAIL RCPT DATA BDAT");
5104 Ustrcat(buffer
, " NOOP QUIT RSET HELP");
5105 if (acl_smtp_etrn
!= NULL
) Ustrcat(buffer
, " ETRN");
5106 if (acl_smtp_expn
!= NULL
) Ustrcat(buffer
, " EXPN");
5107 if (acl_smtp_vrfy
!= NULL
) Ustrcat(buffer
, " VRFY");
5108 smtp_printf("214%s\r\n", buffer
);
5114 incomplete_transaction_log(US
"connection lost");
5115 smtp_notquit_exit(US
"connection-lost", US
"421",
5116 US
"%s lost input connection", smtp_active_hostname
);
5118 /* Don't log by default unless in the middle of a message, as some mailers
5119 just drop the call rather than sending QUIT, and it clutters up the logs.
5122 if (sender_address
!= NULL
|| recipients_count
> 0)
5123 log_write(L_lost_incoming_connection
,
5125 "unexpected %s while reading SMTP command from %s%s",
5126 sender_host_unknown
? "EOF" : "disconnection",
5127 host_and_ident(FALSE
), smtp_read_error
);
5129 else log_write(L_smtp_connection
, LOG_MAIN
, "%s lost%s",
5130 smtp_get_connection_info(), smtp_read_error
);
5138 if (sender_address
!= NULL
)
5140 done
= synprot_error(L_smtp_protocol_error
, 503, NULL
,
5141 US
"ETRN is not permitted inside a transaction");
5145 log_write(L_etrn
, LOG_MAIN
, "ETRN %s received from %s", smtp_cmd_argument
,
5146 host_and_ident(FALSE
));
5148 if ((rc
= acl_check(ACL_WHERE_ETRN
, NULL
, acl_smtp_etrn
,
5149 &user_msg
, &log_msg
)) != OK
)
5151 done
= smtp_handle_acl_fail(ACL_WHERE_ETRN
, rc
, user_msg
, log_msg
);
5155 /* Compute the serialization key for this command. */
5157 etrn_serialize_key
= string_sprintf("etrn-%s\n", smtp_cmd_data
);
5159 /* If a command has been specified for running as a result of ETRN, we
5160 permit any argument to ETRN. If not, only the # standard form is permitted,
5161 since that is strictly the only kind of ETRN that can be implemented
5162 according to the RFC. */
5164 if (smtp_etrn_command
!= NULL
)
5168 etrn_command
= smtp_etrn_command
;
5169 deliver_domain
= smtp_cmd_data
;
5170 rc
= transport_set_up_command(&argv
, smtp_etrn_command
, TRUE
, 0, NULL
,
5171 US
"ETRN processing", &error
);
5172 deliver_domain
= NULL
;
5175 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to set up ETRN command: %s",
5177 smtp_printf("458 Internal failure\r\n");
5182 /* Else set up to call Exim with the -R option. */
5186 if (*smtp_cmd_data
++ != '#')
5188 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
5189 US
"argument must begin with #");
5192 etrn_command
= US
"exim -R";
5193 argv
= CUSS
child_exec_exim(CEE_RETURN_ARGV
, TRUE
, NULL
, TRUE
,
5194 *queue_name
? 4 : 2,
5195 US
"-R", smtp_cmd_data
,
5196 US
"-MCG", queue_name
);
5199 /* If we are host-testing, don't actually do anything. */
5205 debug_printf("ETRN command is: %s\n", etrn_command
);
5206 debug_printf("ETRN command execution skipped\n");
5208 if (user_msg
== NULL
) smtp_printf("250 OK\r\n");
5209 else smtp_user_msg(US
"250", user_msg
);
5214 /* If ETRN queue runs are to be serialized, check the database to
5215 ensure one isn't already running. */
5217 if (smtp_etrn_serialize
&& !enq_start(etrn_serialize_key
, 1))
5219 smtp_printf("458 Already processing %s\r\n", smtp_cmd_data
);
5223 /* Fork a child process and run the command. We don't want to have to
5224 wait for the process at any point, so set SIGCHLD to SIG_IGN before
5225 forking. It should be set that way anyway for external incoming SMTP,
5226 but we save and restore to be tidy. If serialization is required, we
5227 actually run the command in yet another process, so we can wait for it
5228 to complete and then remove the serialization lock. */
5230 oldsignal
= signal(SIGCHLD
, SIG_IGN
);
5232 if ((pid
= fork()) == 0)
5234 smtp_input
= FALSE
; /* This process is not associated with the */
5235 (void)fclose(smtp_in
); /* SMTP call any more. */
5236 (void)fclose(smtp_out
);
5238 signal(SIGCHLD
, SIG_DFL
); /* Want to catch child */
5240 /* If not serializing, do the exec right away. Otherwise, fork down
5241 into another process. */
5243 if (!smtp_etrn_serialize
|| (pid
= fork()) == 0)
5245 DEBUG(D_exec
) debug_print_argv(argv
);
5246 exim_nullstd(); /* Ensure std{in,out,err} exist */
5247 execv(CS argv
[0], (char *const *)argv
);
5248 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "exec of \"%s\" (ETRN) failed: %s",
5249 etrn_command
, strerror(errno
));
5250 _exit(EXIT_FAILURE
); /* paranoia */
5253 /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That
5254 is, we are in the first subprocess, after forking again. All we can do
5255 for a failing fork is to log it. Otherwise, wait for the 2nd process to
5256 complete, before removing the serialization. */
5259 log_write(0, LOG_MAIN
|LOG_PANIC
, "2nd fork for serialized ETRN "
5260 "failed: %s", strerror(errno
));
5264 DEBUG(D_any
) debug_printf("waiting for serialized ETRN process %d\n",
5266 (void)wait(&status
);
5267 DEBUG(D_any
) debug_printf("serialized ETRN process %d ended\n",
5271 enq_end(etrn_serialize_key
);
5272 _exit(EXIT_SUCCESS
);
5275 /* Back in the top level SMTP process. Check that we started a subprocess
5276 and restore the signal state. */
5280 log_write(0, LOG_MAIN
|LOG_PANIC
, "fork of process for ETRN failed: %s",
5282 smtp_printf("458 Unable to fork process\r\n");
5283 if (smtp_etrn_serialize
) enq_end(etrn_serialize_key
);
5287 if (user_msg
== NULL
) smtp_printf("250 OK\r\n");
5288 else smtp_user_msg(US
"250", user_msg
);
5291 signal(SIGCHLD
, oldsignal
);
5296 done
= synprot_error(L_smtp_syntax_error
, 501, NULL
,
5297 US
"unexpected argument data");
5301 /* This currently happens only for NULLs, but could be extended. */
5304 done
= synprot_error(L_smtp_syntax_error
, 0, NULL
, /* Just logs */
5305 US
"NULL character(s) present (shown as '?')");
5306 smtp_printf("501 NULL characters are not allowed in SMTP commands\r\n");
5312 if (smtp_inend
>= smtp_inbuffer
+ in_buffer_size
)
5313 smtp_inend
= smtp_inbuffer
+ in_buffer_size
- 1;
5314 c
= smtp_inend
- smtp_inptr
;
5315 if (c
> 150) c
= 150;
5317 incomplete_transaction_log(US
"sync failure");
5318 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP protocol synchronization error "
5319 "(next input sent too soon: pipelining was%s advertised): "
5320 "rejected \"%s\" %s next input=\"%s\"",
5321 pipelining_advertised
? "" : " not",
5322 smtp_cmd_buffer
, host_and_ident(TRUE
),
5323 string_printing(smtp_inptr
));
5324 smtp_notquit_exit(US
"synchronization-error", US
"554",
5325 US
"SMTP synchronization error");
5326 done
= 1; /* Pretend eof - drops connection */
5330 case TOO_MANY_NONMAIL_CMD
:
5331 s
= smtp_cmd_buffer
;
5332 while (*s
!= 0 && !isspace(*s
)) s
++;
5333 incomplete_transaction_log(US
"too many non-mail commands");
5334 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
5335 "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE
),
5336 (int)(s
- smtp_cmd_buffer
), smtp_cmd_buffer
);
5337 smtp_notquit_exit(US
"bad-commands", US
"554", US
"Too many nonmail commands");
5338 done
= 1; /* Pretend eof - drops connection */
5341 #ifdef SUPPORT_PROXY
5342 case PROXY_FAIL_IGNORE_CMD
:
5343 smtp_printf("503 Command refused, required Proxy negotiation failed\r\n");
5348 if (unknown_command_count
++ >= smtp_max_unknown_commands
)
5350 log_write(L_smtp_syntax_error
, LOG_MAIN
,
5351 "SMTP syntax error in \"%s\" %s %s",
5352 string_printing(smtp_cmd_buffer
), host_and_ident(TRUE
),
5353 US
"unrecognized command");
5354 incomplete_transaction_log(US
"unrecognized command");
5355 smtp_notquit_exit(US
"bad-commands", US
"500",
5356 US
"Too many unrecognized commands");
5358 log_write(0, LOG_MAIN
|LOG_REJECT
, "SMTP call from %s dropped: too many "
5359 "unrecognized commands (last was \"%s\")", host_and_ident(FALSE
),
5360 string_printing(smtp_cmd_buffer
));
5363 done
= synprot_error(L_smtp_syntax_error
, 500, NULL
,
5364 US
"unrecognized command");
5368 /* This label is used by goto's inside loops that want to break out to
5369 the end of the command-processing loop. */
5372 last_was_rej_mail
= was_rej_mail
; /* Remember some last commands for */
5373 last_was_rcpt
= was_rcpt
; /* protocol error handling */
5377 return done
- 2; /* Convert yield values */
5382 /* End of smtp_in.c */