Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
80fea873 | 5 | /* Copyright (c) University of Cambridge 1995 - 2016 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* A number of functions for driving outgoing SMTP calls. */ | |
9 | ||
10 | ||
11 | #include "exim.h" | |
7eb6c37c | 12 | #include "transports/smtp.h" |
059ec3d9 PH |
13 | |
14 | ||
15 | ||
16 | /************************************************* | |
17 | * Find an outgoing interface * | |
18 | *************************************************/ | |
19 | ||
20 | /* This function is called from the smtp transport and also from the callout | |
21 | code in verify.c. Its job is to expand a string to get a list of interfaces, | |
22 | and choose a suitable one (IPv4 or IPv6) for the outgoing address. | |
23 | ||
24 | Arguments: | |
25 | istring string interface setting, may be NULL, meaning "any", in | |
26 | which case the function does nothing | |
27 | host_af AF_INET or AF_INET6 for the outgoing IP address | |
28 | addr the mail address being handled (for setting errors) | |
059ec3d9 PH |
29 | interface point this to the interface |
30 | msg to add to any error message | |
31 | ||
32 | Returns: TRUE on success, FALSE on failure, with error message | |
33 | set in addr and transport_return set to PANIC | |
34 | */ | |
35 | ||
36 | BOOL | |
37 | smtp_get_interface(uschar *istring, int host_af, address_item *addr, | |
6f6dedcc | 38 | uschar **interface, uschar *msg) |
059ec3d9 | 39 | { |
55414b25 | 40 | const uschar * expint; |
059ec3d9 PH |
41 | uschar *iface; |
42 | int sep = 0; | |
43 | ||
fb05276a | 44 | if (!istring) return TRUE; |
059ec3d9 | 45 | |
fb05276a | 46 | if (!(expint = expand_string(istring))) |
059ec3d9 PH |
47 | { |
48 | if (expand_string_forcedfail) return TRUE; | |
49 | addr->transport_return = PANIC; | |
50 | addr->message = string_sprintf("failed to expand \"interface\" " | |
51 | "option for %s: %s", msg, expand_string_message); | |
52 | return FALSE; | |
53 | } | |
54 | ||
059ec3d9 PH |
55 | while (isspace(*expint)) expint++; |
56 | if (*expint == 0) return TRUE; | |
57 | ||
58 | while ((iface = string_nextinlist(&expint, &sep, big_buffer, | |
fb05276a | 59 | big_buffer_size))) |
059ec3d9 PH |
60 | { |
61 | if (string_is_ip_address(iface, NULL) == 0) | |
62 | { | |
63 | addr->transport_return = PANIC; | |
64 | addr->message = string_sprintf("\"%s\" is not a valid IP " | |
65 | "address for the \"interface\" option for %s", | |
66 | iface, msg); | |
67 | return FALSE; | |
68 | } | |
69 | ||
70 | if (((Ustrchr(iface, ':') == NULL)? AF_INET:AF_INET6) == host_af) | |
71 | break; | |
72 | } | |
73 | ||
fb05276a | 74 | if (iface) *interface = string_copy(iface); |
059ec3d9 PH |
75 | return TRUE; |
76 | } | |
77 | ||
78 | ||
79 | ||
80 | /************************************************* | |
81 | * Find an outgoing port * | |
82 | *************************************************/ | |
83 | ||
84 | /* This function is called from the smtp transport and also from the callout | |
85 | code in verify.c. Its job is to find a port number. Note that getservbyname() | |
86 | produces the number in network byte order. | |
87 | ||
88 | Arguments: | |
89 | rstring raw (unexpanded) string representation of the port | |
90 | addr the mail address being handled (for setting errors) | |
91 | port stick the port in here | |
92 | msg for adding to error message | |
93 | ||
94 | Returns: TRUE on success, FALSE on failure, with error message set | |
95 | in addr, and transport_return set to PANIC | |
96 | */ | |
97 | ||
98 | BOOL | |
99 | smtp_get_port(uschar *rstring, address_item *addr, int *port, uschar *msg) | |
100 | { | |
101 | uschar *pstring = expand_string(rstring); | |
102 | ||
00580051 | 103 | if (!pstring) |
059ec3d9 PH |
104 | { |
105 | addr->transport_return = PANIC; | |
106 | addr->message = string_sprintf("failed to expand \"%s\" (\"port\" option) " | |
107 | "for %s: %s", rstring, msg, expand_string_message); | |
108 | return FALSE; | |
109 | } | |
110 | ||
111 | if (isdigit(*pstring)) | |
112 | { | |
113 | uschar *end; | |
114 | *port = Ustrtol(pstring, &end, 0); | |
115 | if (end != pstring + Ustrlen(pstring)) | |
116 | { | |
117 | addr->transport_return = PANIC; | |
118 | addr->message = string_sprintf("invalid port number for %s: %s", msg, | |
119 | pstring); | |
120 | return FALSE; | |
121 | } | |
122 | } | |
123 | ||
124 | else | |
125 | { | |
126 | struct servent *smtp_service = getservbyname(CS pstring, "tcp"); | |
00580051 | 127 | if (!smtp_service) |
059ec3d9 PH |
128 | { |
129 | addr->transport_return = PANIC; | |
130 | addr->message = string_sprintf("TCP port \"%s\" is not defined for %s", | |
131 | pstring, msg); | |
132 | return FALSE; | |
133 | } | |
134 | *port = ntohs(smtp_service->s_port); | |
135 | } | |
136 | ||
137 | return TRUE; | |
138 | } | |
139 | ||
140 | ||
141 | ||
142 | ||
059ec3d9 | 143 | int |
7eb6c37c JH |
144 | smtp_sock_connect(host_item * host, int host_af, int port, uschar * interface, |
145 | transport_instance * tb, int timeout) | |
059ec3d9 | 146 | { |
7eb6c37c JH |
147 | smtp_transport_options_block * ob = |
148 | (smtp_transport_options_block *)tb->options_block; | |
149 | const uschar * dscp = ob->dscp; | |
9e4f5962 PP |
150 | int dscp_value; |
151 | int dscp_level; | |
152 | int dscp_option; | |
059ec3d9 | 153 | int sock; |
7eb6c37c | 154 | int save_errno = 0; |
fb05276a | 155 | BOOL fastopen = FALSE; |
059ec3d9 | 156 | |
0cbf2b82 | 157 | #ifndef DISABLE_EVENT |
7eb6c37c JH |
158 | deliver_host_address = host->address; |
159 | deliver_host_port = port; | |
160 | if (event_raise(tb->event_action, US"tcp:connect", NULL)) return -1; | |
a7538db1 JH |
161 | #endif |
162 | ||
059ec3d9 PH |
163 | if ((sock = ip_socket(SOCK_STREAM, host_af)) < 0) return -1; |
164 | ||
165 | /* Set TCP_NODELAY; Exim does its own buffering. */ | |
166 | ||
d4ff61d1 JH |
167 | if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, US &on, sizeof(on))) |
168 | HDEBUG(D_transport|D_acl|D_v) | |
e1d04f48 | 169 | debug_printf_indent("failed to set NODELAY: %s ", strerror(errno)); |
059ec3d9 | 170 | |
9e4f5962 PP |
171 | /* Set DSCP value, if we can. For now, if we fail to set the value, we don't |
172 | bomb out, just log it and continue in default traffic class. */ | |
173 | ||
174 | if (dscp && dscp_lookup(dscp, host_af, &dscp_level, &dscp_option, &dscp_value)) | |
175 | { | |
176 | HDEBUG(D_transport|D_acl|D_v) | |
e1d04f48 | 177 | debug_printf_indent("DSCP \"%s\"=%x ", dscp, dscp_value); |
9e4f5962 PP |
178 | if (setsockopt(sock, dscp_level, dscp_option, &dscp_value, sizeof(dscp_value)) < 0) |
179 | HDEBUG(D_transport|D_acl|D_v) | |
e1d04f48 | 180 | debug_printf_indent("failed to set DSCP: %s ", strerror(errno)); |
9e4f5962 PP |
181 | /* If the kernel supports IPv4 and IPv6 on an IPv6 socket, we need to set the |
182 | option for both; ignore failures here */ | |
183 | if (host_af == AF_INET6 && | |
184 | dscp_lookup(dscp, AF_INET, &dscp_level, &dscp_option, &dscp_value)) | |
9e4f5962 | 185 | (void) setsockopt(sock, dscp_level, dscp_option, &dscp_value, sizeof(dscp_value)); |
9e4f5962 PP |
186 | } |
187 | ||
fb05276a JH |
188 | #ifdef TCP_FASTOPEN |
189 | if (verify_check_given_host (&ob->hosts_try_fastopen, host) == OK) fastopen = TRUE; | |
190 | #endif | |
191 | ||
059ec3d9 PH |
192 | /* Bind to a specific interface if requested. Caller must ensure the interface |
193 | is the same type (IPv4 or IPv6) as the outgoing address. */ | |
194 | ||
7eb6c37c | 195 | if (interface && ip_bind(sock, host_af, interface, 0) < 0) |
059ec3d9 PH |
196 | { |
197 | save_errno = errno; | |
198 | HDEBUG(D_transport|D_acl|D_v) | |
e1d04f48 | 199 | debug_printf_indent("unable to bind outgoing SMTP call to %s: %s", interface, |
059ec3d9 PH |
200 | strerror(errno)); |
201 | } | |
202 | ||
203 | /* Connect to the remote host, and add keepalive to the socket before returning | |
204 | it, if requested. */ | |
205 | ||
fb05276a | 206 | else if (ip_connect(sock, host_af, host->address, port, timeout, fastopen) < 0) |
059ec3d9 PH |
207 | save_errno = errno; |
208 | ||
209 | /* Either bind() or connect() failed */ | |
210 | ||
211 | if (save_errno != 0) | |
212 | { | |
8e669ac1 | 213 | HDEBUG(D_transport|D_acl|D_v) |
4deaf07d | 214 | { |
e1d04f48 | 215 | debug_printf_indent("failed: %s", CUstrerror(save_errno)); |
8e669ac1 | 216 | if (save_errno == ETIMEDOUT) |
4deaf07d | 217 | debug_printf(" (timeout=%s)", readconf_printtime(timeout)); |
8e669ac1 PH |
218 | debug_printf("\n"); |
219 | } | |
f1e894f3 | 220 | (void)close(sock); |
059ec3d9 PH |
221 | errno = save_errno; |
222 | return -1; | |
223 | } | |
224 | ||
225 | /* Both bind() and connect() succeeded */ | |
226 | ||
227 | else | |
228 | { | |
41c7c167 PH |
229 | union sockaddr_46 interface_sock; |
230 | EXIM_SOCKLEN_T size = sizeof(interface_sock); | |
e1d04f48 | 231 | HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("connected\n"); |
41c7c167 PH |
232 | if (getsockname(sock, (struct sockaddr *)(&interface_sock), &size) == 0) |
233 | sending_ip_address = host_ntoa(-1, &interface_sock, NULL, &sending_port); | |
234 | else | |
235 | { | |
236 | log_write(0, LOG_MAIN | ((errno == ECONNRESET)? 0 : LOG_PANIC), | |
237 | "getsockname() failed: %s", strerror(errno)); | |
238 | close(sock); | |
239 | return -1; | |
240 | } | |
7eb6c37c | 241 | if (ob->keepalive) ip_keepalive(sock, host->address, TRUE); |
059ec3d9 PH |
242 | return sock; |
243 | } | |
244 | } | |
245 | ||
58c30e47 JH |
246 | |
247 | ||
248 | ||
249 | ||
250 | void | |
251 | smtp_port_for_connect(host_item * host, int port) | |
252 | { | |
253 | if (host->port != PORT_NONE) | |
254 | { | |
255 | HDEBUG(D_transport|D_acl|D_v) | |
256 | debug_printf_indent("Transport port=%d replaced by host-specific port=%d\n", port, | |
257 | host->port); | |
258 | port = host->port; | |
259 | } | |
260 | else host->port = port; /* Set the port actually used */ | |
261 | } | |
262 | ||
263 | ||
7eb6c37c JH |
264 | /************************************************* |
265 | * Connect to remote host * | |
266 | *************************************************/ | |
267 | ||
268 | /* Create a socket, and connect it to a remote host. IPv6 addresses are | |
269 | detected by checking for a colon in the address. AF_INET6 is defined even on | |
270 | non-IPv6 systems, to enable the code to be less messy. However, on such systems | |
271 | host->address will always be an IPv4 address. | |
272 | ||
7eb6c37c | 273 | Arguments: |
58c30e47 | 274 | host host item containing name and address and port |
7eb6c37c | 275 | host_af AF_INET or AF_INET6 |
7eb6c37c JH |
276 | interface outgoing interface address or NULL |
277 | timeout timeout value or 0 | |
278 | tb transport | |
279 | ||
280 | Returns: connected socket number, or -1 with errno set | |
281 | */ | |
282 | ||
283 | int | |
58c30e47 | 284 | smtp_connect(host_item *host, int host_af, uschar *interface, |
7eb6c37c JH |
285 | int timeout, transport_instance * tb) |
286 | { | |
58c30e47 | 287 | int port = host->port; |
f0989ec0 | 288 | #ifdef SUPPORT_SOCKS |
7eb6c37c JH |
289 | smtp_transport_options_block * ob = |
290 | (smtp_transport_options_block *)tb->options_block; | |
0539a19d | 291 | #endif |
7eb6c37c | 292 | |
055e2cb4 JH |
293 | callout_address = string_sprintf("[%s]:%d", host->address, port); |
294 | ||
7eb6c37c JH |
295 | HDEBUG(D_transport|D_acl|D_v) |
296 | { | |
297 | uschar * s = US" "; | |
298 | if (interface) s = string_sprintf(" from %s ", interface); | |
f0989ec0 | 299 | #ifdef SUPPORT_SOCKS |
7eb6c37c JH |
300 | if (ob->socks_proxy) s = string_sprintf("%svia proxy ", s); |
301 | #endif | |
e1d04f48 | 302 | debug_printf_indent("Connecting to %s %s%s... ", host->name, callout_address, s); |
7eb6c37c JH |
303 | } |
304 | ||
305 | /* Create and connect the socket */ | |
306 | ||
f0989ec0 | 307 | #ifdef SUPPORT_SOCKS |
7eb6c37c JH |
308 | if (ob->socks_proxy) |
309 | return socks_sock_connect(host, host_af, port, interface, tb, timeout); | |
310 | #endif | |
311 | ||
312 | return smtp_sock_connect(host, host_af, port, interface, tb, timeout); | |
313 | } | |
314 | ||
059ec3d9 PH |
315 | |
316 | /************************************************* | |
317 | * Flush outgoing command buffer * | |
318 | *************************************************/ | |
319 | ||
320 | /* This function is called only from smtp_write_command() below. It flushes | |
321 | the buffer of outgoing commands. There is more than one in the buffer only when | |
322 | pipelining. | |
323 | ||
324 | Argument: | |
325 | outblock the SMTP output block | |
925ac8e4 | 326 | mode further data expected, or plain |
059ec3d9 PH |
327 | |
328 | Returns: TRUE if OK, FALSE on error, with errno set | |
329 | */ | |
330 | ||
331 | static BOOL | |
4e910c01 | 332 | flush_buffer(smtp_outblock * outblock, int mode) |
059ec3d9 PH |
333 | { |
334 | int rc; | |
58fc5fb2 | 335 | int n = outblock->ptr - outblock->buffer; |
925ac8e4 | 336 | BOOL more = mode == SCMD_MORE; |
059ec3d9 | 337 | |
4e910c01 | 338 | HDEBUG(D_transport|D_acl) debug_printf_indent("cmd buf flush %d bytes%s\n", n, |
925ac8e4 | 339 | more ? " (more expected)" : ""); |
4e910c01 | 340 | |
059ec3d9 | 341 | #ifdef SUPPORT_TLS |
817d9f57 | 342 | if (tls_out.active == outblock->sock) |
925ac8e4 | 343 | rc = tls_write(FALSE, outblock->buffer, n, more); |
059ec3d9 PH |
344 | else |
345 | #endif | |
4e910c01 JH |
346 | rc = send(outblock->sock, outblock->buffer, n, |
347 | #ifdef MSG_MORE | |
925ac8e4 | 348 | more ? MSG_MORE : 0 |
4e910c01 JH |
349 | #else |
350 | 0 | |
351 | #endif | |
352 | ); | |
059ec3d9 | 353 | |
059ec3d9 PH |
354 | if (rc <= 0) |
355 | { | |
e1d04f48 | 356 | HDEBUG(D_transport|D_acl) debug_printf_indent("send failed: %s\n", strerror(errno)); |
059ec3d9 PH |
357 | return FALSE; |
358 | } | |
359 | ||
360 | outblock->ptr = outblock->buffer; | |
361 | outblock->cmd_count = 0; | |
362 | return TRUE; | |
363 | } | |
364 | ||
365 | ||
366 | ||
367 | /************************************************* | |
368 | * Write SMTP command * | |
369 | *************************************************/ | |
370 | ||
371 | /* The formatted command is left in big_buffer so that it can be reflected in | |
372 | any error message. | |
373 | ||
374 | Arguments: | |
375 | outblock contains buffer for pipelining, and socket | |
4e910c01 | 376 | mode buffer, write-with-more-likely, write |
059ec3d9 PH |
377 | format a format, starting with one of |
378 | of HELO, MAIL FROM, RCPT TO, DATA, ".", or QUIT. | |
6d5c916c | 379 | If NULL, flush pipeline buffer only. |
059ec3d9 PH |
380 | ... data for the format |
381 | ||
382 | Returns: 0 if command added to pipelining buffer, with nothing transmitted | |
383 | +n if n commands transmitted (may still have buffered the new one) | |
384 | -1 on error, with errno set | |
385 | */ | |
386 | ||
387 | int | |
4e910c01 | 388 | smtp_write_command(smtp_outblock * outblock, int mode, const char *format, ...) |
059ec3d9 PH |
389 | { |
390 | int count; | |
391 | int rc = 0; | |
392 | va_list ap; | |
393 | ||
6d5c916c | 394 | if (format) |
059ec3d9 | 395 | { |
6d5c916c JH |
396 | va_start(ap, format); |
397 | if (!string_vformat(big_buffer, big_buffer_size, CS format, ap)) | |
398 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing " | |
399 | "SMTP"); | |
400 | va_end(ap); | |
401 | count = Ustrlen(big_buffer); | |
402 | ||
403 | if (count > outblock->buffersize) | |
404 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong write_command in outgoing " | |
405 | "SMTP"); | |
406 | ||
407 | if (count > outblock->buffersize - (outblock->ptr - outblock->buffer)) | |
408 | { | |
409 | rc = outblock->cmd_count; /* flush resets */ | |
4e910c01 | 410 | if (!flush_buffer(outblock, SCMD_FLUSH)) return -1; |
6d5c916c | 411 | } |
059ec3d9 | 412 | |
6d5c916c JH |
413 | Ustrncpy(CS outblock->ptr, big_buffer, count); |
414 | outblock->ptr += count; | |
415 | outblock->cmd_count++; | |
416 | count -= 2; | |
417 | big_buffer[count] = 0; /* remove \r\n for error message */ | |
059ec3d9 | 418 | |
6d5c916c JH |
419 | /* We want to hide the actual data sent in AUTH transactions from reflections |
420 | and logs. While authenticating, a flag is set in the outblock to enable this. | |
421 | The AUTH command itself gets any data flattened. Other lines are flattened | |
422 | completely. */ | |
059ec3d9 | 423 | |
6d5c916c | 424 | if (outblock->authenticating) |
059ec3d9 | 425 | { |
6d5c916c JH |
426 | uschar *p = big_buffer; |
427 | if (Ustrncmp(big_buffer, "AUTH ", 5) == 0) | |
428 | { | |
429 | p += 5; | |
430 | while (isspace(*p)) p++; | |
431 | while (!isspace(*p)) p++; | |
432 | while (isspace(*p)) p++; | |
433 | } | |
434 | while (*p != 0) *p++ = '*'; | |
059ec3d9 | 435 | } |
059ec3d9 | 436 | |
e1d04f48 | 437 | HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP>> %s\n", big_buffer); |
6d5c916c | 438 | } |
059ec3d9 | 439 | |
4e910c01 | 440 | if (mode != SCMD_BUFFER) |
059ec3d9 PH |
441 | { |
442 | rc += outblock->cmd_count; /* flush resets */ | |
4e910c01 | 443 | if (!flush_buffer(outblock, mode)) return -1; |
059ec3d9 PH |
444 | } |
445 | ||
446 | return rc; | |
447 | } | |
448 | ||
449 | ||
450 | ||
451 | /************************************************* | |
452 | * Read one line of SMTP response * | |
453 | *************************************************/ | |
454 | ||
455 | /* This function reads one line of SMTP response from the server host. This may | |
456 | not be a complete response - it could be just part of a multiline response. We | |
457 | have to use a buffer for incoming packets, because when pipelining or using | |
458 | LMTP, there may well be more than one response in a single packet. This | |
459 | function is called only from the one that follows. | |
460 | ||
461 | Arguments: | |
462 | inblock the SMTP input block (contains holding buffer, socket, etc.) | |
463 | buffer where to put the line | |
464 | size space available for the line | |
465 | timeout the timeout to use when reading a packet | |
466 | ||
467 | Returns: length of a line that has been put in the buffer | |
468 | -1 otherwise, with errno set | |
469 | */ | |
470 | ||
471 | static int | |
472 | read_response_line(smtp_inblock *inblock, uschar *buffer, int size, int timeout) | |
473 | { | |
474 | uschar *p = buffer; | |
475 | uschar *ptr = inblock->ptr; | |
476 | uschar *ptrend = inblock->ptrend; | |
477 | int sock = inblock->sock; | |
478 | ||
479 | /* Loop for reading multiple packets or reading another packet after emptying | |
480 | a previously-read one. */ | |
481 | ||
482 | for (;;) | |
483 | { | |
484 | int rc; | |
485 | ||
486 | /* If there is data in the input buffer left over from last time, copy | |
487 | characters from it until the end of a line, at which point we can return, | |
488 | having removed any whitespace (which will include CR) at the end of the line. | |
489 | The rules for SMTP say that lines end in CRLF, but there are have been cases | |
490 | of hosts using just LF, and other MTAs are reported to handle this, so we | |
491 | just look for LF. If we run out of characters before the end of a line, | |
492 | carry on to read the next incoming packet. */ | |
493 | ||
494 | while (ptr < ptrend) | |
495 | { | |
496 | int c = *ptr++; | |
497 | if (c == '\n') | |
498 | { | |
499 | while (p > buffer && isspace(p[-1])) p--; | |
500 | *p = 0; | |
501 | inblock->ptr = ptr; | |
502 | return p - buffer; | |
503 | } | |
504 | *p++ = c; | |
505 | if (--size < 4) | |
506 | { | |
507 | *p = 0; /* Leave malformed line for error message */ | |
508 | errno = ERRNO_SMTPFORMAT; | |
509 | return -1; | |
510 | } | |
511 | } | |
512 | ||
513 | /* Need to read a new input packet. */ | |
514 | ||
de6273b4 JH |
515 | if((rc = ip_recv(sock, inblock->buffer, inblock->buffersize, timeout)) <= 0) |
516 | { | |
170f4904 JH |
517 | DEBUG(D_deliver|D_transport|D_acl) |
518 | debug_printf_indent(errno ? " SMTP(%s)<<\n" : " SMTP(closed)<<\n", | |
519 | strerror(errno)); | |
de6273b4 JH |
520 | break; |
521 | } | |
059ec3d9 PH |
522 | |
523 | /* Another block of data has been successfully read. Set up the pointers | |
524 | and let the loop continue. */ | |
525 | ||
526 | ptrend = inblock->ptrend = inblock->buffer + rc; | |
527 | ptr = inblock->buffer; | |
e1d04f48 | 528 | DEBUG(D_transport|D_acl) debug_printf_indent("read response data: size=%d\n", rc); |
059ec3d9 PH |
529 | } |
530 | ||
531 | /* Get here if there has been some kind of recv() error; errno is set, but we | |
532 | ensure that the result buffer is empty before returning. */ | |
533 | ||
534 | *buffer = 0; | |
535 | return -1; | |
536 | } | |
537 | ||
538 | ||
539 | ||
540 | ||
541 | ||
542 | /************************************************* | |
543 | * Read SMTP response * | |
544 | *************************************************/ | |
545 | ||
546 | /* This function reads an SMTP response with a timeout, and returns the | |
547 | response in the given buffer, as a string. A multiline response will contain | |
548 | newline characters between the lines. The function also analyzes the first | |
549 | digit of the reply code and returns FALSE if it is not acceptable. FALSE is | |
550 | also returned after a reading error. In this case buffer[0] will be zero, and | |
551 | the error code will be in errno. | |
552 | ||
553 | Arguments: | |
554 | inblock the SMTP input block (contains holding buffer, socket, etc.) | |
555 | buffer where to put the response | |
556 | size the size of the buffer | |
557 | okdigit the expected first digit of the response | |
2760b518 | 558 | timeout the timeout to use, in seconds |
059ec3d9 PH |
559 | |
560 | Returns: TRUE if a valid, non-error response was received; else FALSE | |
561 | */ | |
562 | ||
563 | BOOL | |
564 | smtp_read_response(smtp_inblock *inblock, uschar *buffer, int size, int okdigit, | |
565 | int timeout) | |
566 | { | |
567 | uschar *ptr = buffer; | |
568 | int count; | |
569 | ||
570 | errno = 0; /* Ensure errno starts out zero */ | |
571 | ||
4c04137d | 572 | /* This is a loop to read and concatenate the lines that make up a multi-line |
059ec3d9 PH |
573 | response. */ |
574 | ||
575 | for (;;) | |
576 | { | |
577 | if ((count = read_response_line(inblock, ptr, size, timeout)) < 0) | |
578 | return FALSE; | |
579 | ||
580 | HDEBUG(D_transport|D_acl|D_v) | |
e1d04f48 | 581 | debug_printf_indent(" %s %s\n", (ptr == buffer)? "SMTP<<" : " ", ptr); |
059ec3d9 PH |
582 | |
583 | /* Check the format of the response: it must start with three digits; if | |
584 | these are followed by a space or end of line, the response is complete. If | |
585 | they are followed by '-' this is a multi-line response and we must look for | |
586 | another line until the final line is reached. The only use made of multi-line | |
587 | responses is to pass them back as error messages. We therefore just | |
588 | concatenate them all within the buffer, which should be large enough to | |
589 | accept any reasonable number of lines. */ | |
590 | ||
591 | if (count < 3 || | |
592 | !isdigit(ptr[0]) || | |
593 | !isdigit(ptr[1]) || | |
594 | !isdigit(ptr[2]) || | |
595 | (ptr[3] != '-' && ptr[3] != ' ' && ptr[3] != 0)) | |
596 | { | |
597 | errno = ERRNO_SMTPFORMAT; /* format error */ | |
598 | return FALSE; | |
599 | } | |
600 | ||
601 | /* If the line we have just read is a terminal line, line, we are done. | |
602 | Otherwise more data has to be read. */ | |
603 | ||
604 | if (ptr[3] != '-') break; | |
605 | ||
606 | /* Move the reading pointer upwards in the buffer and insert \n between the | |
607 | components of a multiline response. Space is left for this by read_response_ | |
608 | line(). */ | |
609 | ||
610 | ptr += count; | |
611 | *ptr++ = '\n'; | |
612 | size -= count + 1; | |
613 | } | |
614 | ||
615 | /* Return a value that depends on the SMTP return code. On some systems a | |
616 | non-zero value of errno has been seen at this point, so ensure it is zero, | |
617 | because the caller of this function looks at errno when FALSE is returned, to | |
618 | distinguish between an unexpected return code and other errors such as | |
619 | timeouts, lost connections, etc. */ | |
620 | ||
621 | errno = 0; | |
622 | return buffer[0] == okdigit; | |
623 | } | |
624 | ||
625 | /* End of smtp_out.c */ | |
7eb6c37c JH |
626 | /* vi: aw ai sw=2 |
627 | */ |