Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
f9ba5e22 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
1e1ddfac | 6 | /* Copyright (c) The Exim Maintainers 2020 */ |
059ec3d9 PH |
7 | /* See the file NOTICE for conditions of use and distribution. */ |
8 | ||
9 | /* Functions concerned with running Exim as a daemon */ | |
10 | ||
11 | ||
12 | #include "exim.h" | |
13 | ||
14 | ||
15 | /* Structure for holding data for each SMTP connection */ | |
16 | ||
17 | typedef struct smtp_slot { | |
18 | pid_t pid; /* pid of the spawned reception process */ | |
19 | uschar *host_address; /* address of the client host */ | |
20 | } smtp_slot; | |
21 | ||
22 | /* An empty slot for initializing (Standard C does not allow constructor | |
4c04137d | 23 | expressions in assignments except as initializers in declarations). */ |
059ec3d9 | 24 | |
f2ed27cf | 25 | static smtp_slot empty_smtp_slot = { .pid = 0, .host_address = NULL }; |
059ec3d9 PH |
26 | |
27 | ||
28 | ||
29 | /************************************************* | |
30 | * Local static variables * | |
31 | *************************************************/ | |
32 | ||
cd59ab18 PP |
33 | static SIGNAL_BOOL sigchld_seen; |
34 | static SIGNAL_BOOL sighup_seen; | |
01446a56 | 35 | static SIGNAL_BOOL sigterm_seen; |
059ec3d9 PH |
36 | |
37 | static int accept_retry_count = 0; | |
38 | static int accept_retry_errno; | |
39 | static BOOL accept_retry_select_failed; | |
40 | ||
41 | static int queue_run_count = 0; | |
bb6e88ff PH |
42 | static pid_t *queue_pid_slots = NULL; |
43 | static smtp_slot *smtp_slots = NULL; | |
059ec3d9 PH |
44 | |
45 | static BOOL write_pid = TRUE; | |
46 | ||
47 | ||
48 | ||
49 | /************************************************* | |
50 | * SIGHUP Handler * | |
51 | *************************************************/ | |
52 | ||
53 | /* All this handler does is to set a flag and re-enable the signal. | |
54 | ||
55 | Argument: the signal number | |
56 | Returns: nothing | |
57 | */ | |
58 | ||
59 | static void | |
60 | sighup_handler(int sig) | |
61 | { | |
62 | sig = sig; /* Keep picky compilers happy */ | |
63 | sighup_seen = TRUE; | |
64 | signal(SIGHUP, sighup_handler); | |
65 | } | |
66 | ||
67 | ||
68 | ||
69 | /************************************************* | |
70 | * SIGCHLD handler for main daemon process * | |
71 | *************************************************/ | |
72 | ||
73 | /* Don't re-enable the handler here, since we aren't doing the | |
74 | waiting here. If the signal is re-enabled, there will just be an | |
75 | infinite sequence of calls to this handler. The SIGCHLD signal is | |
76 | used just as a means of waking up the daemon so that it notices | |
77 | terminated subprocesses as soon as possible. | |
78 | ||
79 | Argument: the signal number | |
80 | Returns: nothing | |
81 | */ | |
82 | ||
83 | static void | |
84 | main_sigchld_handler(int sig) | |
85 | { | |
86 | sig = sig; /* Keep picky compilers happy */ | |
7d468ab8 | 87 | os_non_restarting_signal(SIGCHLD, SIG_DFL); |
059ec3d9 | 88 | sigchld_seen = TRUE; |
059ec3d9 PH |
89 | } |
90 | ||
91 | ||
01446a56 JH |
92 | /* SIGTERM handler. Try to get the damon pif file removed |
93 | before exiting. */ | |
94 | ||
95 | static void | |
96 | main_sigterm_handler(int sig) | |
97 | { | |
98 | sigterm_seen = TRUE; | |
99 | } | |
100 | ||
101 | ||
059ec3d9 PH |
102 | |
103 | ||
104 | /************************************************* | |
105 | * Unexpected errors in SMTP calls * | |
106 | *************************************************/ | |
107 | ||
108 | /* This function just saves a bit of repetitious coding. | |
109 | ||
110 | Arguments: | |
111 | log_msg Text of message to be logged | |
112 | smtp_msg Text of SMTP error message | |
113 | was_errno The failing errno | |
114 | ||
115 | Returns: nothing | |
116 | */ | |
117 | ||
118 | static void | |
119 | never_error(uschar *log_msg, uschar *smtp_msg, int was_errno) | |
120 | { | |
52f12a7c JH |
121 | uschar *emsg = was_errno <= 0 |
122 | ? US"" : string_sprintf(": %s", strerror(was_errno)); | |
059ec3d9 | 123 | log_write(0, LOG_MAIN|LOG_PANIC, "%s%s", log_msg, emsg); |
52f12a7c | 124 | if (smtp_out) smtp_printf("421 %s\r\n", FALSE, smtp_msg); |
059ec3d9 PH |
125 | } |
126 | ||
127 | ||
128 | ||
129 | ||
8cfc4d82 JH |
130 | /************************************************* |
131 | *************************************************/ | |
132 | ||
133 | static void | |
134 | close_daemon_sockets(int daemon_notifier_fd, | |
135 | int * listen_sockets, int listen_socket_count) | |
136 | { | |
137 | if (daemon_notifier_fd >= 0) (void) close(daemon_notifier_fd); | |
138 | for (int i = 0; i < listen_socket_count; i++) (void) close(listen_sockets[i]); | |
139 | } | |
140 | ||
141 | ||
059ec3d9 PH |
142 | /************************************************* |
143 | * Handle a connected SMTP call * | |
144 | *************************************************/ | |
145 | ||
146 | /* This function is called when an SMTP connection has been accepted. | |
147 | If there are too many, give an error message and close down. Otherwise | |
148 | spin off a sub-process to handle the call. The list of listening sockets | |
149 | is required so that they can be closed in the sub-process. Take care not to | |
150 | leak store in this process - reset the stacking pool at the end. | |
151 | ||
152 | Arguments: | |
153 | listen_sockets sockets which are listening for incoming calls | |
154 | listen_socket_count count of listening sockets | |
155 | accept_socket socket of the current accepted call | |
156 | accepted socket information about the current call | |
157 | ||
158 | Returns: nothing | |
159 | */ | |
160 | ||
161 | static void | |
162 | handle_smtp_call(int *listen_sockets, int listen_socket_count, | |
163 | int accept_socket, struct sockaddr *accepted) | |
164 | { | |
165 | pid_t pid; | |
166 | union sockaddr_46 interface_sockaddr; | |
36a3b041 | 167 | EXIM_SOCKLEN_T ifsize = sizeof(interface_sockaddr); |
059ec3d9 PH |
168 | int dup_accept_socket = -1; |
169 | int max_for_this_host = 0; | |
6c6d6e48 | 170 | int save_log_selector = *log_selector; |
b2bcdd35 | 171 | gstring * whofrom; |
059ec3d9 | 172 | |
f3ebb786 | 173 | rmark reset_point = store_mark(); |
059ec3d9 PH |
174 | |
175 | /* Make the address available in ASCII representation, and also fish out | |
176 | the remote port. */ | |
177 | ||
178 | sender_host_address = host_ntoa(-1, accepted, NULL, &sender_host_port); | |
179 | DEBUG(D_any) debug_printf("Connection request from %s port %d\n", | |
180 | sender_host_address, sender_host_port); | |
181 | ||
182 | /* Set up the output stream, check the socket has duplicated, and set up the | |
183 | input stream. These operations fail only the exceptional circumstances. Note | |
184 | that never_error() won't use smtp_out if it is NULL. */ | |
185 | ||
f5d25c2b | 186 | if (!(smtp_out = fdopen(accept_socket, "wb"))) |
059ec3d9 PH |
187 | { |
188 | never_error(US"daemon: fdopen() for smtp_out failed", US"", errno); | |
189 | goto ERROR_RETURN; | |
190 | } | |
191 | ||
f5d25c2b | 192 | if ((dup_accept_socket = dup(accept_socket)) < 0) |
059ec3d9 PH |
193 | { |
194 | never_error(US"daemon: couldn't dup socket descriptor", | |
195 | US"Connection setup failed", errno); | |
196 | goto ERROR_RETURN; | |
197 | } | |
198 | ||
f5d25c2b | 199 | if (!(smtp_in = fdopen(dup_accept_socket, "rb"))) |
059ec3d9 PH |
200 | { |
201 | never_error(US"daemon: fdopen() for smtp_in failed", | |
202 | US"Connection setup failed", errno); | |
203 | goto ERROR_RETURN; | |
204 | } | |
205 | ||
520de300 PH |
206 | /* Get the data for the local interface address. Panic for most errors, but |
207 | "connection reset by peer" just means the connection went away. */ | |
059ec3d9 PH |
208 | |
209 | if (getsockname(accept_socket, (struct sockaddr *)(&interface_sockaddr), | |
210 | &ifsize) < 0) | |
211 | { | |
520de300 PH |
212 | log_write(0, LOG_MAIN | ((errno == ECONNRESET)? 0 : LOG_PANIC), |
213 | "getsockname() failed: %s", strerror(errno)); | |
925ac8e4 | 214 | smtp_printf("421 Local problem: getsockname() failed; please try again later\r\n", FALSE); |
059ec3d9 PH |
215 | goto ERROR_RETURN; |
216 | } | |
217 | ||
218 | interface_address = host_ntoa(-1, &interface_sockaddr, NULL, &interface_port); | |
219 | DEBUG(D_interface) debug_printf("interface address=%s port=%d\n", | |
220 | interface_address, interface_port); | |
221 | ||
222 | /* Build a string identifying the remote host and, if requested, the port and | |
223 | the local interface data. This is for logging; at the end of this function the | |
224 | memory is reclaimed. */ | |
225 | ||
b2bcdd35 | 226 | whofrom = string_append(NULL, 3, "[", sender_host_address, "]"); |
059ec3d9 | 227 | |
6c6d6e48 | 228 | if (LOGGING(incoming_port)) |
52f12a7c | 229 | whofrom = string_fmt_append(whofrom, ":%d", sender_host_port); |
059ec3d9 | 230 | |
6c6d6e48 | 231 | if (LOGGING(incoming_interface)) |
52f12a7c JH |
232 | whofrom = string_fmt_append(whofrom, " I=[%s]:%d", |
233 | interface_address, interface_port); | |
059ec3d9 | 234 | |
acec9514 | 235 | (void) string_from_gstring(whofrom); /* Terminate the newly-built string */ |
059ec3d9 PH |
236 | |
237 | /* Check maximum number of connections. We do not check for reserved | |
238 | connections or unacceptable hosts here. That is done in the subprocess because | |
239 | it might take some time. */ | |
240 | ||
241 | if (smtp_accept_max > 0 && smtp_accept_count >= smtp_accept_max) | |
242 | { | |
243 | DEBUG(D_any) debug_printf("rejecting SMTP connection: count=%d max=%d\n", | |
244 | smtp_accept_count, smtp_accept_max); | |
245 | smtp_printf("421 Too many concurrent SMTP connections; " | |
925ac8e4 | 246 | "please try again later.\r\n", FALSE); |
059ec3d9 PH |
247 | log_write(L_connection_reject, |
248 | LOG_MAIN, "Connection from %s refused: too many connections", | |
acec9514 | 249 | whofrom->s); |
059ec3d9 PH |
250 | goto ERROR_RETURN; |
251 | } | |
252 | ||
253 | /* If a load limit above which only reserved hosts are acceptable is defined, | |
254 | get the load average here, and if there are in fact no reserved hosts, do | |
255 | the test right away (saves a fork). If there are hosts, do the check in the | |
256 | subprocess because it might take time. */ | |
257 | ||
258 | if (smtp_load_reserve >= 0) | |
259 | { | |
8669f003 | 260 | load_average = OS_GETLOADAVG(); |
059ec3d9 PH |
261 | if (smtp_reserve_hosts == NULL && load_average > smtp_load_reserve) |
262 | { | |
263 | DEBUG(D_any) debug_printf("rejecting SMTP connection: load average = %.2f\n", | |
264 | (double)load_average/1000.0); | |
925ac8e4 | 265 | smtp_printf("421 Too much load; please try again later.\r\n", FALSE); |
059ec3d9 PH |
266 | log_write(L_connection_reject, |
267 | LOG_MAIN, "Connection from %s refused: load average = %.2f", | |
acec9514 | 268 | whofrom->s, (double)load_average/1000.0); |
059ec3d9 PH |
269 | goto ERROR_RETURN; |
270 | } | |
271 | } | |
272 | ||
273 | /* Check that one specific host (strictly, IP address) is not hogging | |
274 | resources. This is done here to prevent a denial of service attack by someone | |
275 | forcing you to fork lots of times before denying service. The value of | |
276 | smtp_accept_max_per_host is a string which is expanded. This makes it possible | |
277 | to provide host-specific limits according to $sender_host address, but because | |
278 | this is in the daemon mainline, only fast expansions (such as inline address | |
279 | checks) should be used. The documentation is full of warnings. */ | |
280 | ||
281 | if (smtp_accept_max_per_host != NULL) | |
282 | { | |
283 | uschar *expanded = expand_string(smtp_accept_max_per_host); | |
284 | if (expanded == NULL) | |
285 | { | |
8768d548 | 286 | if (!f.expand_string_forcedfail) |
059ec3d9 | 287 | log_write(0, LOG_MAIN|LOG_PANIC, "expansion of smtp_accept_max_per_host " |
acec9514 | 288 | "failed for %s: %s", whofrom->s, expand_string_message); |
059ec3d9 PH |
289 | } |
290 | /* For speed, interpret a decimal number inline here */ | |
291 | else | |
292 | { | |
293 | uschar *s = expanded; | |
294 | while (isdigit(*s)) | |
295 | max_for_this_host = max_for_this_host * 10 + *s++ - '0'; | |
296 | if (*s != 0) | |
297 | log_write(0, LOG_MAIN|LOG_PANIC, "expansion of smtp_accept_max_per_host " | |
acec9514 | 298 | "for %s contains non-digit: %s", whofrom->s, expanded); |
059ec3d9 PH |
299 | } |
300 | } | |
301 | ||
302 | /* If we have fewer connections than max_for_this_host, we can skip the tedious | |
303 | per host_address checks. Note that at this stage smtp_accept_count contains the | |
304 | count of *other* connections, not including this one. */ | |
305 | ||
306 | if ((max_for_this_host > 0) && | |
307 | (smtp_accept_count >= max_for_this_host)) | |
308 | { | |
059ec3d9 PH |
309 | int host_accept_count = 0; |
310 | int other_host_count = 0; /* keep a count of non matches to optimise */ | |
311 | ||
d7978c0f | 312 | for (int i = 0; i < smtp_accept_max; ++i) |
8cfd0f7b | 313 | if (smtp_slots[i].host_address) |
059ec3d9 PH |
314 | { |
315 | if (Ustrcmp(sender_host_address, smtp_slots[i].host_address) == 0) | |
316 | host_accept_count++; | |
317 | else | |
318 | other_host_count++; | |
319 | ||
320 | /* Testing all these strings is expensive - see if we can drop out | |
321 | early, either by hitting the target, or finding there are not enough | |
322 | connections left to make the target. */ | |
323 | ||
324 | if ((host_accept_count >= max_for_this_host) || | |
325 | ((smtp_accept_count - other_host_count) < max_for_this_host)) | |
326 | break; | |
327 | } | |
059ec3d9 PH |
328 | |
329 | if (host_accept_count >= max_for_this_host) | |
330 | { | |
331 | DEBUG(D_any) debug_printf("rejecting SMTP connection: too many from this " | |
332 | "IP address: count=%d max=%d\n", | |
333 | host_accept_count, max_for_this_host); | |
334 | smtp_printf("421 Too many concurrent SMTP connections " | |
925ac8e4 | 335 | "from this IP address; please try again later.\r\n", FALSE); |
059ec3d9 PH |
336 | log_write(L_connection_reject, |
337 | LOG_MAIN, "Connection from %s refused: too many connections " | |
acec9514 | 338 | "from that IP address", whofrom->s); |
059ec3d9 PH |
339 | goto ERROR_RETURN; |
340 | } | |
341 | } | |
342 | ||
343 | /* OK, the connection count checks have been passed. Before we can fork the | |
344 | accepting process, we must first log the connection if requested. This logging | |
345 | used to happen in the subprocess, but doing that means that the value of | |
346 | smtp_accept_count can be out of step by the time it is logged. So we have to do | |
347 | the logging here and accept the performance cost. Note that smtp_accept_count | |
348 | hasn't yet been incremented to take account of this connection. | |
349 | ||
350 | In order to minimize the cost (because this is going to happen for every | |
351 | connection), do a preliminary selector test here. This saves ploughing through | |
352 | the generalized logging code each time when the selector is false. If the | |
353 | selector is set, check whether the host is on the list for logging. If not, | |
354 | arrange to unset the selector in the subprocess. */ | |
355 | ||
6c6d6e48 | 356 | if (LOGGING(smtp_connection)) |
059ec3d9 PH |
357 | { |
358 | uschar *list = hosts_connection_nolog; | |
ce325893 | 359 | memset(sender_host_cache, 0, sizeof(sender_host_cache)); |
059ec3d9 | 360 | if (list != NULL && verify_check_host(&list) == OK) |
6c6d6e48 | 361 | save_log_selector &= ~L_smtp_connection; |
059ec3d9 PH |
362 | else |
363 | log_write(L_smtp_connection, LOG_MAIN, "SMTP connection from %s " | |
acec9514 | 364 | "(TCP/IP connection count = %d)", whofrom->s, smtp_accept_count + 1); |
059ec3d9 PH |
365 | } |
366 | ||
367 | /* Now we can fork the accepting process; do a lookup tidy, just in case any | |
368 | expansion above did a lookup. */ | |
369 | ||
370 | search_tidyup(); | |
81022793 | 371 | pid = exim_fork(US"daemon-accept"); |
059ec3d9 PH |
372 | |
373 | /* Handle the child process */ | |
374 | ||
375 | if (pid == 0) | |
376 | { | |
059ec3d9 PH |
377 | int queue_only_reason = 0; |
378 | int old_pool = store_pool; | |
8e669ac1 | 379 | int save_debug_selector = debug_selector; |
059ec3d9 | 380 | BOOL local_queue_only; |
8669f003 | 381 | BOOL session_local_queue_only; |
059ec3d9 PH |
382 | #ifdef SA_NOCLDWAIT |
383 | struct sigaction act; | |
384 | #endif | |
385 | ||
b01dd148 PH |
386 | smtp_accept_count++; /* So that it includes this process */ |
387 | ||
059ec3d9 PH |
388 | /* May have been modified for the subprocess */ |
389 | ||
6c6d6e48 | 390 | *log_selector = save_log_selector; |
059ec3d9 PH |
391 | |
392 | /* Get the local interface address into permanent store */ | |
393 | ||
394 | store_pool = POOL_PERM; | |
395 | interface_address = string_copy(interface_address); | |
396 | store_pool = old_pool; | |
397 | ||
398 | /* Check for a tls-on-connect port */ | |
399 | ||
817d9f57 | 400 | if (host_is_tls_on_connect_port(interface_port)) tls_in.on_connect = TRUE; |
059ec3d9 PH |
401 | |
402 | /* Expand smtp_active_hostname if required. We do not do this any earlier, | |
403 | because it may depend on the local interface address (indeed, that is most | |
404 | likely what it depends on.) */ | |
405 | ||
406 | smtp_active_hostname = primary_hostname; | |
ad7fc6eb | 407 | if (raw_active_hostname) |
059ec3d9 | 408 | { |
ad7fc6eb JH |
409 | uschar * nah = expand_string(raw_active_hostname); |
410 | if (!nah) | |
059ec3d9 | 411 | { |
8768d548 | 412 | if (!f.expand_string_forcedfail) |
059ec3d9 PH |
413 | { |
414 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand \"%s\" " | |
415 | "(smtp_active_hostname): %s", raw_active_hostname, | |
416 | expand_string_message); | |
417 | smtp_printf("421 Local configuration error; " | |
925ac8e4 | 418 | "please try again later.\r\n", FALSE); |
059ec3d9 PH |
419 | mac_smtp_fflush(); |
420 | search_tidyup(); | |
81022793 | 421 | exim_underbar_exit(EXIT_FAILURE); |
059ec3d9 PH |
422 | } |
423 | } | |
ad7fc6eb | 424 | else if (*nah) smtp_active_hostname = nah; |
059ec3d9 PH |
425 | } |
426 | ||
427 | /* Initialize the queueing flags */ | |
428 | ||
429 | queue_check_only(); | |
8669f003 | 430 | session_local_queue_only = queue_only; |
059ec3d9 PH |
431 | |
432 | /* Close the listening sockets, and set the SIGCHLD handler to SIG_IGN. | |
433 | We also attempt to set things up so that children are automatically reaped, | |
434 | but just in case this isn't available, there's a paranoid waitpid() in the | |
435 | loop too (except for systems where we are sure it isn't needed). See the more | |
436 | extensive comment before the reception loop in exim.c for a fuller | |
437 | explanation of this logic. */ | |
438 | ||
8cfc4d82 | 439 | close_daemon_sockets(daemon_notifier_fd, listen_sockets, listen_socket_count); |
059ec3d9 | 440 | |
fa32850b DW |
441 | /* Set FD_CLOEXEC on the SMTP socket. We don't want any rogue child processes |
442 | to be able to communicate with them, under any circumstances. */ | |
443 | (void)fcntl(accept_socket, F_SETFD, | |
444 | fcntl(accept_socket, F_GETFD) | FD_CLOEXEC); | |
445 | (void)fcntl(dup_accept_socket, F_SETFD, | |
446 | fcntl(dup_accept_socket, F_GETFD) | FD_CLOEXEC); | |
447 | ||
059ec3d9 PH |
448 | #ifdef SA_NOCLDWAIT |
449 | act.sa_handler = SIG_IGN; | |
450 | sigemptyset(&(act.sa_mask)); | |
451 | act.sa_flags = SA_NOCLDWAIT; | |
452 | sigaction(SIGCHLD, &act, NULL); | |
453 | #else | |
454 | signal(SIGCHLD, SIG_IGN); | |
455 | #endif | |
01446a56 | 456 | signal(SIGTERM, SIG_DFL); |
059ec3d9 PH |
457 | |
458 | /* Attempt to get an id from the sending machine via the RFC 1413 | |
459 | protocol. We do this in the sub-process in order not to hold up the | |
460 | main process if there is any delay. Then set up the fullhost information | |
8e669ac1 PH |
461 | in case there is no HELO/EHLO. |
462 | ||
463 | If debugging is enabled only for the daemon, we must turn if off while | |
464 | finding the id, but turn it on again afterwards so that information about the | |
3d235903 | 465 | incoming connection is output. */ |
8e669ac1 | 466 | |
8768d548 | 467 | if (f.debug_daemon) debug_selector = 0; |
059ec3d9 PH |
468 | verify_get_ident(IDENT_PORT); |
469 | host_build_sender_fullhost(); | |
8e669ac1 | 470 | debug_selector = save_debug_selector; |
059ec3d9 PH |
471 | |
472 | DEBUG(D_any) | |
473 | debug_printf("Process %d is handling incoming connection from %s\n", | |
474 | (int)getpid(), sender_fullhost); | |
475 | ||
3d235903 PH |
476 | /* Now disable debugging permanently if it's required only for the daemon |
477 | process. */ | |
478 | ||
8768d548 | 479 | if (f.debug_daemon) debug_selector = 0; |
3d235903 | 480 | |
059ec3d9 | 481 | /* If there are too many child processes for immediate delivery, |
8669f003 | 482 | set the session_local_queue_only flag, which is initialized from the |
059ec3d9 | 483 | configured value and may therefore already be TRUE. Leave logging |
8669f003 PH |
484 | till later so it will have a message id attached. Note that there is no |
485 | possibility of re-calculating this per-message, because the value of | |
486 | smtp_accept_count does not change in this subprocess. */ | |
059ec3d9 | 487 | |
b01dd148 | 488 | if (smtp_accept_queue > 0 && smtp_accept_count > smtp_accept_queue) |
059ec3d9 | 489 | { |
8669f003 | 490 | session_local_queue_only = TRUE; |
059ec3d9 PH |
491 | queue_only_reason = 1; |
492 | } | |
493 | ||
494 | /* Handle the start of the SMTP session, then loop, accepting incoming | |
495 | messages from the SMTP connection. The end will come at the QUIT command, | |
496 | when smtp_setup_msg() returns 0. A break in the connection causes the | |
24796b8d PH |
497 | process to die (see accept.c). |
498 | ||
499 | NOTE: We do *not* call smtp_log_no_mail() if smtp_start_session() fails, | |
500 | because a log line has already been written for all its failure exists | |
501 | (usually "connection refused: <reason>") and writing another one is | |
502 | unnecessary clutter. */ | |
059ec3d9 PH |
503 | |
504 | if (!smtp_start_session()) | |
505 | { | |
506 | mac_smtp_fflush(); | |
507 | search_tidyup(); | |
81022793 | 508 | exim_underbar_exit(EXIT_SUCCESS); |
059ec3d9 PH |
509 | } |
510 | ||
511 | for (;;) | |
512 | { | |
513 | int rc; | |
514 | message_id[0] = 0; /* Clear out any previous message_id */ | |
f3ebb786 | 515 | reset_point = store_mark(); /* Save current store high water point */ |
059ec3d9 PH |
516 | |
517 | DEBUG(D_any) | |
518 | debug_printf("Process %d is ready for new message\n", (int)getpid()); | |
519 | ||
520 | /* Smtp_setup_msg() returns 0 on QUIT or if the call is from an | |
521 | unacceptable host or if an ACL "drop" command was triggered, -1 on | |
522 | connection lost, and +1 on validly reaching DATA. Receive_msg() almost | |
523 | always returns TRUE when smtp_input is true; just retry if no message was | |
524 | accepted (can happen for invalid message parameters). However, it can yield | |
525 | FALSE if the connection was forcibly dropped by the DATA ACL. */ | |
526 | ||
527 | if ((rc = smtp_setup_msg()) > 0) | |
528 | { | |
529 | BOOL ok = receive_msg(FALSE); | |
530 | search_tidyup(); /* Close cached databases */ | |
531 | if (!ok) /* Connection was dropped */ | |
532 | { | |
57cc2785 | 533 | cancel_cutthrough_connection(TRUE, US"receive dropped"); |
059ec3d9 | 534 | mac_smtp_fflush(); |
b4ed4da0 | 535 | smtp_log_no_mail(); /* Log no mail if configured */ |
81022793 | 536 | exim_underbar_exit(EXIT_SUCCESS); |
059ec3d9 PH |
537 | } |
538 | if (message_id[0] == 0) continue; /* No message was accepted */ | |
539 | } | |
540 | else | |
541 | { | |
ad7fc6eb JH |
542 | if (smtp_out) |
543 | { | |
d7978c0f | 544 | int fd = fileno(smtp_in); |
ad7fc6eb JH |
545 | uschar buf[128]; |
546 | ||
547 | mac_smtp_fflush(); | |
548 | /* drain socket, for clean TCP FINs */ | |
5ddc9771 | 549 | if (fcntl(fd, F_SETFL, O_NONBLOCK) == 0) |
d7978c0f | 550 | for(int i = 16; read(fd, buf, sizeof(buf)) > 0 && i > 0; ) i--; |
ad7fc6eb | 551 | } |
57cc2785 | 552 | cancel_cutthrough_connection(TRUE, US"message setup dropped"); |
059ec3d9 | 553 | search_tidyup(); |
b4ed4da0 | 554 | smtp_log_no_mail(); /* Log no mail if configured */ |
60d10ce7 JH |
555 | |
556 | /*XXX should we pause briefly, hoping that the client will be the | |
557 | active TCP closer hence get the TCP_WAIT endpoint? */ | |
558 | DEBUG(D_receive) debug_printf("SMTP>>(close on process exit)\n"); | |
81022793 | 559 | exim_underbar_exit(rc ? EXIT_FAILURE : EXIT_SUCCESS); |
059ec3d9 PH |
560 | } |
561 | ||
562 | /* Show the recipients when debugging */ | |
563 | ||
564 | DEBUG(D_receive) | |
565 | { | |
2c0f3ea1 | 566 | if (sender_address) |
059ec3d9 | 567 | debug_printf("Sender: %s\n", sender_address); |
2c0f3ea1 | 568 | if (recipients_list) |
059ec3d9 PH |
569 | { |
570 | debug_printf("Recipients:\n"); | |
d7978c0f | 571 | for (int i = 0; i < recipients_count; i++) |
059ec3d9 PH |
572 | debug_printf(" %s\n", recipients_list[i].address); |
573 | } | |
574 | } | |
575 | ||
576 | /* A message has been accepted. Clean up any previous delivery processes | |
577 | that have completed and are defunct, on systems where they don't go away | |
578 | by themselves (see comments when setting SIG_IGN above). On such systems | |
579 | (if any) these delivery processes hang around after termination until | |
580 | the next message is received. */ | |
581 | ||
582 | #ifndef SIG_IGN_WORKS | |
583 | while (waitpid(-1, NULL, WNOHANG) > 0); | |
584 | #endif | |
585 | ||
586 | /* Reclaim up the store used in accepting this message */ | |
587 | ||
e04bfa34 JH |
588 | { |
589 | int r = receive_messagecount; | |
8768d548 | 590 | BOOL q = f.queue_only_policy; |
e04bfa34 | 591 | smtp_reset(reset_point); |
f3ebb786 | 592 | reset_point = NULL; |
8768d548 | 593 | f.queue_only_policy = q; |
e04bfa34 JH |
594 | receive_messagecount = r; |
595 | } | |
059ec3d9 PH |
596 | |
597 | /* If queue_only is set or if there are too many incoming connections in | |
8669f003 PH |
598 | existence, session_local_queue_only will be TRUE. If it is not, check |
599 | whether we have received too many messages in this session for immediate | |
600 | delivery. */ | |
601 | ||
602 | if (!session_local_queue_only && | |
603 | smtp_accept_queue_per_connection > 0 && | |
604 | receive_messagecount > smtp_accept_queue_per_connection) | |
059ec3d9 | 605 | { |
8669f003 PH |
606 | session_local_queue_only = TRUE; |
607 | queue_only_reason = 2; | |
608 | } | |
609 | ||
610 | /* Initialize local_queue_only from session_local_queue_only. If it is not | |
611 | true, and queue_only_load is set, check that the load average is below it. | |
612 | If local_queue_only is set by this means, we also set if for the session if | |
613 | queue_only_load_latch is true (the default). This means that, once set, | |
614 | local_queue_only remains set for any subsequent messages on the same SMTP | |
615 | connection. This is a deliberate choice; even though the load average may | |
616 | fall, it doesn't seem right to deliver later messages on the same call when | |
617 | not delivering earlier ones. However, the are special circumstances such as | |
618 | very long-lived connections from scanning appliances where this is not the | |
619 | best strategy. In such cases, queue_only_load_latch should be set false. */ | |
620 | ||
f5d25c2b JH |
621 | if ( !(local_queue_only = session_local_queue_only) |
622 | && queue_only_load >= 0 | |
623 | && (local_queue_only = (load_average = OS_GETLOADAVG()) > queue_only_load) | |
624 | ) | |
8669f003 | 625 | { |
f5d25c2b JH |
626 | queue_only_reason = 3; |
627 | if (queue_only_load_latch) session_local_queue_only = TRUE; | |
059ec3d9 PH |
628 | } |
629 | ||
630 | /* Log the queueing here, when it will get a message id attached, but | |
631 | not if queue_only is set (case 0). */ | |
632 | ||
633 | if (local_queue_only) switch(queue_only_reason) | |
634 | { | |
f5d25c2b | 635 | case 1: log_write(L_delay_delivery, |
059ec3d9 PH |
636 | LOG_MAIN, "no immediate delivery: too many connections " |
637 | "(%d, max %d)", smtp_accept_count, smtp_accept_queue); | |
f5d25c2b | 638 | break; |
059ec3d9 | 639 | |
f5d25c2b | 640 | case 2: log_write(L_delay_delivery, |
059ec3d9 PH |
641 | LOG_MAIN, "no immediate delivery: more than %d messages " |
642 | "received in one connection", smtp_accept_queue_per_connection); | |
f5d25c2b | 643 | break; |
059ec3d9 | 644 | |
f5d25c2b | 645 | case 3: log_write(L_delay_delivery, |
059ec3d9 PH |
646 | LOG_MAIN, "no immediate delivery: load average %.2f", |
647 | (double)load_average/1000.0); | |
f5d25c2b | 648 | break; |
059ec3d9 PH |
649 | } |
650 | ||
651 | /* If a delivery attempt is required, spin off a new process to handle it. | |
652 | If we are not root, we have to re-exec exim unless deliveries are being | |
653 | done unprivileged. */ | |
654 | ||
9438970c JH |
655 | else if ( (!f.queue_only_policy || f.queue_smtp) |
656 | && !f.deliver_freeze) | |
059ec3d9 PH |
657 | { |
658 | pid_t dpid; | |
659 | ||
660 | /* Before forking, ensure that the C output buffer is flushed. Otherwise | |
661 | anything that it in it will get duplicated, leading to duplicate copies | |
662 | of the pending output. */ | |
663 | ||
664 | mac_smtp_fflush(); | |
665 | ||
4b01271f | 666 | if ((dpid = exim_fork(US"daemon-accept-delivery")) == 0) |
059ec3d9 | 667 | { |
f1e894f3 PH |
668 | (void)fclose(smtp_in); |
669 | (void)fclose(smtp_out); | |
059ec3d9 PH |
670 | |
671 | /* Don't ever molest the parent's SSL connection, but do clean up | |
672 | the data structures if necessary. */ | |
673 | ||
01603eec | 674 | #ifndef DISABLE_TLS |
74f1a423 | 675 | tls_close(NULL, TLS_NO_SHUTDOWN); |
57cc2785 | 676 | #endif |
059ec3d9 PH |
677 | |
678 | /* Reset SIGHUP and SIGCHLD in the child in both cases. */ | |
679 | ||
680 | signal(SIGHUP, SIG_DFL); | |
681 | signal(SIGCHLD, SIG_DFL); | |
01446a56 | 682 | signal(SIGTERM, SIG_DFL); |
059ec3d9 PH |
683 | |
684 | if (geteuid() != root_uid && !deliver_drop_privilege) | |
685 | { | |
686 | signal(SIGALRM, SIG_DFL); | |
57cc2785 | 687 | delivery_re_exec(CEE_EXEC_PANIC); |
059ec3d9 PH |
688 | /* Control does not return here. */ |
689 | } | |
690 | ||
691 | /* No need to re-exec; SIGALRM remains set to the default handler */ | |
692 | ||
57cc2785 | 693 | (void) deliver_message(message_id, FALSE, FALSE); |
059ec3d9 | 694 | search_tidyup(); |
81022793 | 695 | exim_underbar_exit(EXIT_SUCCESS); |
059ec3d9 PH |
696 | } |
697 | ||
698 | if (dpid > 0) | |
699 | { | |
57cc2785 | 700 | release_cutthrough_connection(US"passed for delivery"); |
059ec3d9 PH |
701 | DEBUG(D_any) debug_printf("forked delivery process %d\n", (int)dpid); |
702 | } | |
703 | else | |
57cc2785 JH |
704 | { |
705 | cancel_cutthrough_connection(TRUE, US"delivery fork failed"); | |
059ec3d9 PH |
706 | log_write(0, LOG_MAIN|LOG_PANIC, "daemon: delivery process fork " |
707 | "failed: %s", strerror(errno)); | |
57cc2785 | 708 | } |
059ec3d9 PH |
709 | } |
710 | } | |
711 | } | |
712 | ||
713 | ||
714 | /* Carrying on in the parent daemon process... Can't do much if the fork | |
715 | failed. Otherwise, keep count of the number of accepting processes and | |
716 | remember the pid for ticking off when the child completes. */ | |
717 | ||
718 | if (pid < 0) | |
059ec3d9 | 719 | never_error(US"daemon: accept process fork failed", US"Fork failed", errno); |
059ec3d9 PH |
720 | else |
721 | { | |
d7978c0f | 722 | for (int i = 0; i < smtp_accept_max; ++i) |
059ec3d9 PH |
723 | if (smtp_slots[i].pid <= 0) |
724 | { | |
725 | smtp_slots[i].pid = pid; | |
f3ebb786 JH |
726 | /* Connection closes come asyncronously, so we cannot stack this store */ |
727 | if (smtp_accept_max_per_host) | |
059ec3d9 PH |
728 | smtp_slots[i].host_address = string_copy_malloc(sender_host_address); |
729 | smtp_accept_count++; | |
730 | break; | |
731 | } | |
059ec3d9 | 732 | DEBUG(D_any) debug_printf("%d SMTP accept process%s running\n", |
f3ebb786 | 733 | smtp_accept_count, smtp_accept_count == 1 ? "" : "es"); |
059ec3d9 PH |
734 | } |
735 | ||
736 | /* Get here via goto in error cases */ | |
737 | ||
738 | ERROR_RETURN: | |
739 | ||
740 | /* Close the streams associated with the socket which will also close the | |
741 | socket fds in this process. We can't do anything if fclose() fails, but | |
742 | logging brings it to someone's attention. However, "connection reset by peer" | |
1f872c80 PH |
743 | isn't really a problem, so skip that one. On Solaris, a dropped connection can |
744 | manifest itself as a broken pipe, so drop that one too. If the streams don't | |
745 | exist, something went wrong while setting things up. Make sure the socket | |
746 | descriptors are closed, in order to drop the connection. */ | |
059ec3d9 | 747 | |
f5d25c2b | 748 | if (smtp_out) |
059ec3d9 | 749 | { |
1f872c80 | 750 | if (fclose(smtp_out) != 0 && errno != ECONNRESET && errno != EPIPE) |
059ec3d9 PH |
751 | log_write(0, LOG_MAIN|LOG_PANIC, "daemon: fclose(smtp_out) failed: %s", |
752 | strerror(errno)); | |
753 | smtp_out = NULL; | |
754 | } | |
f1e894f3 | 755 | else (void)close(accept_socket); |
059ec3d9 | 756 | |
f5d25c2b | 757 | if (smtp_in) |
059ec3d9 | 758 | { |
1f872c80 | 759 | if (fclose(smtp_in) != 0 && errno != ECONNRESET && errno != EPIPE) |
059ec3d9 PH |
760 | log_write(0, LOG_MAIN|LOG_PANIC, "daemon: fclose(smtp_in) failed: %s", |
761 | strerror(errno)); | |
762 | smtp_in = NULL; | |
763 | } | |
f1e894f3 | 764 | else (void)close(dup_accept_socket); |
059ec3d9 PH |
765 | |
766 | /* Release any store used in this process, including the store used for holding | |
767 | the incoming host address and an expanded active_hostname. */ | |
768 | ||
c8899c20 | 769 | log_close_all(); |
90341c71 JH |
770 | interface_address = |
771 | sender_host_address = NULL; | |
059ec3d9 PH |
772 | store_reset(reset_point); |
773 | sender_host_address = NULL; | |
774 | } | |
775 | ||
776 | ||
777 | ||
778 | ||
779 | /************************************************* | |
780 | * Check wildcard listen special cases * | |
781 | *************************************************/ | |
782 | ||
783 | /* This function is used when binding and listening on lists of addresses and | |
784 | ports. It tests for special cases of wildcard listening, when IPv4 and IPv6 | |
785 | sockets may interact in different ways in different operating systems. It is | |
786 | passed an error number, the list of listening addresses, and the current | |
787 | address. Two checks are available: for a previous wildcard IPv6 address, or for | |
788 | a following wildcard IPv4 address, in both cases on the same port. | |
789 | ||
790 | In practice, pairs of wildcard addresses should be adjacent in the address list | |
791 | because they are sorted that way below. | |
792 | ||
793 | Arguments: | |
794 | eno the error number | |
795 | addresses the list of addresses | |
796 | ipa the current IP address | |
797 | back if TRUE, check for previous wildcard IPv6 address | |
798 | if FALSE, check for a following wildcard IPv4 address | |
799 | ||
800 | Returns: TRUE or FALSE | |
801 | */ | |
802 | ||
803 | static BOOL | |
804 | check_special_case(int eno, ip_address_item *addresses, ip_address_item *ipa, | |
805 | BOOL back) | |
806 | { | |
807 | ip_address_item *ipa2; | |
808 | ||
809 | /* For the "back" case, if the failure was "address in use" for a wildcard IPv4 | |
810 | address, seek a previous IPv6 wildcard address on the same port. As it is | |
811 | previous, it must have been successfully bound and be listening. Flag it as a | |
812 | "6 including 4" listener. */ | |
813 | ||
814 | if (back) | |
815 | { | |
816 | if (eno != EADDRINUSE || ipa->address[0] != 0) return FALSE; | |
817 | for (ipa2 = addresses; ipa2 != ipa; ipa2 = ipa2->next) | |
818 | { | |
819 | if (ipa2->address[1] == 0 && ipa2->port == ipa->port) | |
820 | { | |
821 | ipa2->v6_include_v4 = TRUE; | |
822 | return TRUE; | |
823 | } | |
824 | } | |
825 | } | |
826 | ||
827 | /* For the "forward" case, if the current address is a wildcard IPv6 address, | |
828 | we seek a following wildcard IPv4 address on the same port. */ | |
829 | ||
830 | else | |
831 | { | |
832 | if (ipa->address[0] != ':' || ipa->address[1] != 0) return FALSE; | |
833 | for (ipa2 = ipa->next; ipa2 != NULL; ipa2 = ipa2->next) | |
834 | if (ipa2->address[0] == 0 && ipa->port == ipa2->port) return TRUE; | |
835 | } | |
836 | ||
837 | return FALSE; | |
838 | } | |
839 | ||
840 | ||
841 | ||
842 | ||
bb6e88ff PH |
843 | /************************************************* |
844 | * Handle terminating subprocesses * | |
845 | *************************************************/ | |
846 | ||
847 | /* Handle the termination of child processes. Theoretically, this need be done | |
848 | only when sigchld_seen is TRUE, but rumour has it that some systems lose | |
849 | SIGCHLD signals at busy times, so to be on the safe side, this function is | |
850 | called each time round. It shouldn't be too expensive. | |
851 | ||
852 | Arguments: none | |
853 | Returns: nothing | |
854 | */ | |
855 | ||
856 | static void | |
857 | handle_ending_processes(void) | |
858 | { | |
859 | int status; | |
860 | pid_t pid; | |
861 | ||
862 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0) | |
863 | { | |
7be682ca PP |
864 | DEBUG(D_any) |
865 | { | |
866 | debug_printf("child %d ended: status=0x%x\n", (int)pid, status); | |
867 | #ifdef WCOREDUMP | |
868 | if (WIFEXITED(status)) | |
869 | debug_printf(" normal exit, %d\n", WEXITSTATUS(status)); | |
870 | else if (WIFSIGNALED(status)) | |
871 | debug_printf(" signal exit, signal %d%s\n", WTERMSIG(status), | |
872 | WCOREDUMP(status) ? " (core dumped)" : ""); | |
873 | #endif | |
874 | } | |
bb6e88ff | 875 | |
8e669ac1 | 876 | /* If it's a listening daemon for which we are keeping track of individual |
bb6e88ff PH |
877 | subprocesses, deal with an accepting process that has terminated. */ |
878 | ||
8cfd0f7b | 879 | if (smtp_slots) |
bb6e88ff | 880 | { |
f3ebb786 | 881 | int i; |
bb6e88ff | 882 | for (i = 0; i < smtp_accept_max; i++) |
bb6e88ff PH |
883 | if (smtp_slots[i].pid == pid) |
884 | { | |
8cfd0f7b | 885 | if (smtp_slots[i].host_address) |
bb6e88ff PH |
886 | store_free(smtp_slots[i].host_address); |
887 | smtp_slots[i] = empty_smtp_slot; | |
888 | if (--smtp_accept_count < 0) smtp_accept_count = 0; | |
889 | DEBUG(D_any) debug_printf("%d SMTP accept process%s now running\n", | |
890 | smtp_accept_count, (smtp_accept_count == 1)? "" : "es"); | |
891 | break; | |
892 | } | |
bb6e88ff PH |
893 | if (i < smtp_accept_max) continue; /* Found an accepting process */ |
894 | } | |
895 | ||
896 | /* If it wasn't an accepting process, see if it was a queue-runner | |
897 | process that we are tracking. */ | |
898 | ||
0cd5fd23 | 899 | if (queue_pid_slots) |
bb6e88ff | 900 | { |
4dc2379a | 901 | int max = atoi(CS expand_string(queue_run_max)); |
f3ebb786 | 902 | for (int i = 0; i < max; i++) |
bb6e88ff PH |
903 | if (queue_pid_slots[i] == pid) |
904 | { | |
905 | queue_pid_slots[i] = 0; | |
906 | if (--queue_run_count < 0) queue_run_count = 0; | |
907 | DEBUG(D_any) debug_printf("%d queue-runner process%s now running\n", | |
908 | queue_run_count, (queue_run_count == 1)? "" : "es"); | |
909 | break; | |
910 | } | |
bb6e88ff PH |
911 | } |
912 | } | |
913 | } | |
914 | ||
059ec3d9 PH |
915 | |
916 | ||
01446a56 JH |
917 | static void |
918 | set_pid_file_path(void) | |
919 | { | |
920 | if (override_pid_file_path) | |
921 | pid_file_path = override_pid_file_path; | |
922 | ||
923 | if (!*pid_file_path) | |
924 | pid_file_path = string_sprintf("%s/exim-daemon.pid", spool_directory); | |
925 | } | |
926 | ||
927 | ||
928 | /* Remove the daemon's pidfile. Note: runs with root privilege, | |
929 | as a direct child of the daemon. Does not return. */ | |
930 | ||
931 | void | |
932 | delete_pid_file(void) | |
933 | { | |
934 | uschar * daemon_pid = string_sprintf("%d\n", (int)getppid()); | |
935 | FILE * f; | |
936 | ||
937 | set_pid_file_path(); | |
938 | if ((f = Ufopen(pid_file_path, "rb"))) | |
939 | { | |
940 | if ( fgets(CS big_buffer, big_buffer_size, f) | |
941 | && Ustrcmp(daemon_pid, big_buffer) == 0 | |
942 | ) | |
943 | if (Uunlink(pid_file_path) == 0) | |
944 | { | |
945 | DEBUG(D_any) | |
946 | debug_printf("%s unlink: %s\n", pid_file_path, strerror(errno)); | |
947 | } | |
948 | else | |
949 | DEBUG(D_any) | |
950 | debug_printf("unlinked %s\n", pid_file_path); | |
951 | fclose(f); | |
952 | } | |
953 | else | |
954 | DEBUG(D_any) | |
955 | debug_printf("%s\n", string_open_failed(errno, "pid file %s", | |
956 | pid_file_path)); | |
81022793 | 957 | exim_exit(EXIT_SUCCESS); |
01446a56 JH |
958 | } |
959 | ||
960 | ||
961 | /* Called by the daemon; exec a child to get the pid file deleted | |
962 | since we may require privs for the containing directory */ | |
963 | ||
964 | static void | |
965 | daemon_die(void) | |
966 | { | |
967 | int pid; | |
968 | ||
2f2dd3a5 JH |
969 | if (daemon_notifier_fd >= 0) |
970 | { | |
971 | close(daemon_notifier_fd); | |
972 | daemon_notifier_fd = -1; | |
973 | #ifndef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS | |
974 | { | |
691ca88c | 975 | uschar * s = expand_string(notifier_socket); |
2f2dd3a5 JH |
976 | DEBUG(D_any) debug_printf("unlinking notifier socket %s\n", s); |
977 | Uunlink(s); | |
978 | } | |
979 | #endif | |
980 | } | |
981 | ||
01446a56 JH |
982 | if (f.running_in_test_harness || write_pid) |
983 | { | |
4b01271f | 984 | if ((pid = exim_fork(US"daemon-del-pidfile")) == 0) |
01446a56 JH |
985 | { |
986 | if (override_pid_file_path) | |
987 | (void)child_exec_exim(CEE_EXEC_PANIC, FALSE, NULL, FALSE, 3, | |
988 | "-oP", override_pid_file_path, "-oPX"); | |
989 | else | |
990 | (void)child_exec_exim(CEE_EXEC_PANIC, FALSE, NULL, FALSE, 1, "-oPX"); | |
991 | ||
992 | /* Control never returns here. */ | |
993 | } | |
994 | if (pid > 0) | |
995 | child_close(pid, 1); | |
996 | } | |
81022793 | 997 | exim_exit(EXIT_SUCCESS); |
01446a56 JH |
998 | } |
999 | ||
1000 | ||
ff966302 JH |
1001 | /************************************************* |
1002 | * Listener socket for local work prompts * | |
1003 | *************************************************/ | |
1004 | ||
1005 | static void | |
1006 | daemon_notifier_socket(void) | |
1007 | { | |
1008 | int fd; | |
1009 | const uschar * where; | |
3978c243 | 1010 | struct sockaddr_un sa_un = {.sun_family = AF_UNIX}; |
04403ab0 | 1011 | int len; |
ff966302 | 1012 | |
691ca88c JH |
1013 | if (override_local_interfaces && !override_pid_file_path) |
1014 | { | |
1015 | DEBUG(D_any) | |
1016 | debug_printf("-oX used without -oP so not creating notifier socket\n"); | |
1017 | return; | |
1018 | } | |
1019 | ||
1020 | DEBUG(D_any) debug_printf("creating notifier socket\n"); | |
ff966302 | 1021 | |
ff966302 | 1022 | #ifdef SOCK_CLOEXEC |
2f2dd3a5 | 1023 | if ((fd = socket(PF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) |
4a9f055c | 1024 | { where = US"socket"; goto bad; } |
ff966302 | 1025 | #else |
4a9f055c JH |
1026 | if ((fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) |
1027 | { where = US"socket"; goto bad; } | |
ff966302 JH |
1028 | (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC); |
1029 | #endif | |
1030 | ||
2f2dd3a5 | 1031 | #ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS |
3978c243 | 1032 | sa_un.sun_path[0] = 0; /* Abstract local socket addr - Linux-specific? */ |
04403ab0 | 1033 | len = offsetof(struct sockaddr_un, sun_path) + 1 |
691ca88c JH |
1034 | + snprintf(sa_un.sun_path+1, sizeof(sa_un.sun_path)-1, "%s", |
1035 | expand_string(notifier_socket)); | |
1036 | DEBUG(D_any) debug_printf(" @%s\n", sa_un.sun_path+1); | |
2f2dd3a5 JH |
1037 | #else /* filesystem-visible and persistent; will neeed removal */ |
1038 | len = offsetof(struct sockaddr_un, sun_path) | |
691ca88c JH |
1039 | + snprintf(sa_un.sun_path, sizeof(sa_un.sun_path), "%s", |
1040 | expand_string(notifier_socket)); | |
1041 | DEBUG(D_any) debug_printf(" %s\n", sa_un.sun_path); | |
2f2dd3a5 | 1042 | #endif |
04403ab0 | 1043 | |
3978c243 | 1044 | if (bind(fd, (const struct sockaddr *)&sa_un, len) < 0) |
4a9f055c | 1045 | { where = US"bind"; goto bad; } |
ff966302 | 1046 | |
5399df80 | 1047 | #ifdef SO_PASSCRED /* Linux */ |
2f2dd3a5 | 1048 | if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)) < 0) |
4a9f055c | 1049 | { where = US"SO_PASSCRED"; goto bad2; } |
2f2dd3a5 | 1050 | #elif defined(LOCAL_CREDS) /* FreeBSD-ish */ |
4a9f055c JH |
1051 | if (setsockopt(fd, 0, LOCAL_CREDS, &on, sizeof(on)) < 0) |
1052 | { where = US"LOCAL_CREDS"; goto bad2; } | |
2f2dd3a5 | 1053 | #endif |
ff966302 JH |
1054 | |
1055 | /* debug_printf("%s: fd %d\n", __FUNCTION__, fd); */ | |
1056 | daemon_notifier_fd = fd; | |
1057 | return; | |
1058 | ||
4a9f055c JH |
1059 | bad2: |
1060 | #ifndef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS | |
1061 | Uunlink(sa_un.sun_path); | |
1062 | #endif | |
ff966302 | 1063 | bad: |
4a9f055c | 1064 | log_write(0, LOG_MAIN|LOG_PANIC, "%s %s: %s", |
ff966302 | 1065 | __FUNCTION__, where, strerror(errno)); |
4a9f055c JH |
1066 | close(fd); |
1067 | return; | |
ff966302 JH |
1068 | } |
1069 | ||
1070 | ||
1071 | static uschar queuerun_msgid[MESSAGE_ID_LENGTH+1]; | |
1072 | ||
1073 | /* Return TRUE if a sigalrm should be emulated */ | |
1074 | static BOOL | |
1075 | daemon_notification(void) | |
1076 | { | |
1077 | uschar buf[256], cbuf[256]; | |
3978c243 | 1078 | struct sockaddr_un sa_un; |
017de05c | 1079 | struct iovec iov = {.iov_base = buf, .iov_len = sizeof(buf)-1}; |
3978c243 JH |
1080 | struct msghdr msg = { .msg_name = &sa_un, |
1081 | .msg_namelen = sizeof(sa_un), | |
ff966302 JH |
1082 | .msg_iov = &iov, |
1083 | .msg_iovlen = 1, | |
1084 | .msg_control = cbuf, | |
1085 | .msg_controllen = sizeof(cbuf) | |
1086 | }; | |
1087 | ssize_t sz; | |
ff966302 JH |
1088 | |
1089 | buf[sizeof(buf)-1] = 0; | |
1090 | if ((sz = recvmsg(daemon_notifier_fd, &msg, 0)) <= 0) return FALSE; | |
1091 | if (sz >= sizeof(buf)) return FALSE; | |
1092 | ||
04403ab0 JH |
1093 | #ifdef notdef |
1094 | debug_printf("addrlen %d\n", msg.msg_namelen); | |
1095 | #endif | |
2f2dd3a5 | 1096 | DEBUG(D_queue_run) debug_printf("%s from addr '%s%.*s'\n", __FUNCTION__, |
3978c243 JH |
1097 | *sa_un.sun_path ? "" : "@", |
1098 | (int)msg.msg_namelen - (*sa_un.sun_path ? 0 : 1), | |
1099 | sa_un.sun_path + (*sa_un.sun_path ? 0 : 1)); | |
04403ab0 JH |
1100 | |
1101 | /* Refuse to handle the item unless the peer has good credentials */ | |
f254e592 JH |
1102 | #ifdef SCM_CREDENTIALS |
1103 | # define EXIM_SCM_CR_TYPE SCM_CREDENTIALS | |
5399df80 | 1104 | #elif defined(LOCAL_CREDS) && defined(SCM_CREDS) |
f254e592 JH |
1105 | # define EXIM_SCM_CR_TYPE SCM_CREDS |
1106 | #else | |
2f2dd3a5 JH |
1107 | /* The OS has no way to get the creds of the caller (for a unix/datagram socket. |
1108 | Punt; don't try to check. */ | |
f254e592 | 1109 | #endif |
04403ab0 | 1110 | |
2f2dd3a5 | 1111 | #ifdef EXIM_SCM_CR_TYPE |
ff966302 JH |
1112 | for (struct cmsghdr * cp = CMSG_FIRSTHDR(&msg); |
1113 | cp; | |
1114 | cp = CMSG_NXTHDR(&msg, cp)) | |
f254e592 | 1115 | if (cp->cmsg_level == SOL_SOCKET && cp->cmsg_type == EXIM_SCM_CR_TYPE) |
ff966302 | 1116 | { |
2f2dd3a5 | 1117 | # ifdef SCM_CREDENTIALS /* Linux */ |
ff966302 JH |
1118 | struct ucred * cr = (struct ucred *) CMSG_DATA(cp); |
1119 | if (cr->uid && cr->uid != exim_uid) | |
1120 | { | |
1121 | DEBUG(D_queue_run) debug_printf("%s: sender creds pid %d uid %d gid %d\n", | |
1122 | __FUNCTION__, (int)cr->pid, (int)cr->uid, (int)cr->gid); | |
1123 | return FALSE; | |
2f2dd3a5 JH |
1124 | } |
1125 | # elif defined(LOCAL_CREDS) /* BSD-ish */ | |
5399df80 JH |
1126 | struct sockcred * cr = (struct sockcred *) CMSG_DATA(cp); |
1127 | if (cr->sc_uid && cr->sc_uid != exim_uid) | |
f254e592 | 1128 | { |
5399df80 JH |
1129 | DEBUG(D_queue_run) debug_printf("%s: sender creds pid ??? uid %d gid %d\n", |
1130 | __FUNCTION__, (int)cr->sc_uid, (int)cr->sc_gid); | |
f254e592 | 1131 | return FALSE; |
ff966302 | 1132 | } |
2f2dd3a5 | 1133 | # endif |
ff966302 JH |
1134 | break; |
1135 | } | |
2f2dd3a5 | 1136 | #endif |
ff966302 JH |
1137 | |
1138 | buf[sz] = 0; | |
1139 | switch (buf[0]) | |
1140 | { | |
4c2efd7a | 1141 | #ifdef EXPERIMENTAL_QUEUE_RAMP |
ff966302 JH |
1142 | case NOTIFY_MSG_QRUN: |
1143 | /* this should be a message_id */ | |
1144 | DEBUG(D_queue_run) | |
1145 | debug_printf("%s: qrunner trigger: %s\n", __FUNCTION__, buf+1); | |
1146 | memcpy(queuerun_msgid, buf+1, MESSAGE_ID_LENGTH+1); | |
1147 | return TRUE; | |
4c2efd7a | 1148 | #endif /*EXPERIMENTAL_QUEUE_RAMP*/ |
04403ab0 JH |
1149 | |
1150 | case NOTIFY_QUEUE_SIZE_REQ: | |
1151 | { | |
1152 | uschar buf[16]; | |
1153 | int len = snprintf(CS buf, sizeof(buf), "%u", queue_count_cached()); | |
1154 | ||
1155 | DEBUG(D_queue_run) | |
1156 | debug_printf("%s: queue size request: %s\n", __FUNCTION__, buf); | |
1157 | ||
f254e592 | 1158 | if (sendto(daemon_notifier_fd, buf, len, 0, |
3978c243 | 1159 | (const struct sockaddr *)&sa_un, msg.msg_namelen) < 0) |
04403ab0 JH |
1160 | log_write(0, LOG_MAIN|LOG_PANIC, |
1161 | "%s: sendto: %s\n", __FUNCTION__, strerror(errno)); | |
1162 | return FALSE; | |
1163 | } | |
ff966302 JH |
1164 | } |
1165 | return FALSE; | |
1166 | } | |
ff966302 JH |
1167 | |
1168 | ||
059ec3d9 PH |
1169 | /************************************************* |
1170 | * Exim Daemon Mainline * | |
1171 | *************************************************/ | |
1172 | ||
1173 | /* The daemon can do two jobs, either of which is optional: | |
1174 | ||
1175 | (1) Listens for incoming SMTP calls and spawns off a sub-process to handle | |
1176 | each one. This is requested by the -bd option, with -oX specifying the SMTP | |
1177 | port on which to listen (for testing). | |
1178 | ||
1179 | (2) Spawns a queue-running process every so often. This is controlled by the | |
1180 | -q option with a an interval time. (If no time is given, a single queue run | |
1181 | is done from the main function, and control doesn't get here.) | |
1182 | ||
1183 | Root privilege is required in order to attach to port 25. Some systems require | |
1184 | it when calling socket() rather than bind(). To cope with all cases, we run as | |
1185 | root for both socket() and bind(). Some systems also require root in order to | |
1186 | write to the pid file directory. This function must therefore be called as root | |
1187 | if it is to work properly in all circumstances. Once the socket is bound and | |
1188 | the pid file written, root privilege is given up if there is an exim uid. | |
1189 | ||
1190 | There are no arguments to this function, and it never returns. */ | |
1191 | ||
1192 | void | |
1193 | daemon_go(void) | |
1194 | { | |
ebeaf996 | 1195 | struct passwd *pw; |
059ec3d9 PH |
1196 | int *listen_sockets = NULL; |
1197 | int listen_socket_count = 0; | |
1198 | ip_address_item *addresses = NULL; | |
9ee44efb | 1199 | time_t last_connection_time = (time_t)0; |
4dc2379a | 1200 | int local_queue_run_max = atoi(CS expand_string(queue_run_max)); |
059ec3d9 | 1201 | |
81022793 JH |
1202 | process_purpose = US"daemon"; |
1203 | ||
059ec3d9 PH |
1204 | /* If any debugging options are set, turn on the D_pid bit so that all |
1205 | debugging lines get the pid added. */ | |
1206 | ||
1207 | DEBUG(D_any|D_v) debug_selector |= D_pid; | |
1208 | ||
8768d548 | 1209 | if (f.inetd_wait_mode) |
9ee44efb | 1210 | { |
9ee44efb | 1211 | listen_socket_count = 1; |
f3ebb786 | 1212 | listen_sockets = store_get(sizeof(int), FALSE); |
9ee44efb PP |
1213 | (void) close(3); |
1214 | if (dup2(0, 3) == -1) | |
9ee44efb PP |
1215 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
1216 | "failed to dup inetd socket safely away: %s", strerror(errno)); | |
d4ff61d1 | 1217 | |
9ee44efb PP |
1218 | listen_sockets[0] = 3; |
1219 | (void) close(0); | |
1220 | (void) close(1); | |
1221 | (void) close(2); | |
1222 | exim_nullstd(); | |
1223 | ||
1224 | if (debug_file == stderr) | |
1225 | { | |
1226 | /* need a call to log_write before call to open debug_file, so that | |
1227 | log.c:file_path has been initialised. This is unfortunate. */ | |
1228 | log_write(0, LOG_MAIN, "debugging Exim in inetd wait mode starting"); | |
1229 | ||
1230 | fclose(debug_file); | |
1231 | debug_file = NULL; | |
1232 | exim_nullstd(); /* re-open fd2 after we just closed it again */ | |
1233 | debug_logging_activate(US"-wait", NULL); | |
1234 | } | |
1235 | ||
1236 | DEBUG(D_any) debug_printf("running in inetd wait mode\n"); | |
1237 | ||
1238 | /* As per below, when creating sockets ourselves, we handle tcp_nodelay for | |
1239 | our own buffering; we assume though that inetd set the socket REUSEADDR. */ | |
1240 | ||
d4ff61d1 JH |
1241 | if (tcp_nodelay) |
1242 | if (setsockopt(3, IPPROTO_TCP, TCP_NODELAY, US &on, sizeof(on))) | |
1243 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to set socket NODELAY: %s", | |
1244 | strerror(errno)); | |
9ee44efb PP |
1245 | } |
1246 | ||
1247 | ||
8768d548 | 1248 | if (f.inetd_wait_mode || f.daemon_listen) |
9ee44efb PP |
1249 | { |
1250 | /* If any option requiring a load average to be available during the | |
1251 | reception of a message is set, call os_getloadavg() while we are root | |
1252 | for those OS for which this is necessary the first time it is called (in | |
1253 | order to perform an "open" on the kernel memory file). */ | |
1254 | ||
1255 | #ifdef LOAD_AVG_NEEDS_ROOT | |
1256 | if (queue_only_load >= 0 || smtp_load_reserve >= 0 || | |
1257 | (deliver_queue_load_max >= 0 && deliver_drop_privilege)) | |
1258 | (void)os_getloadavg(); | |
1259 | #endif | |
1260 | } | |
1261 | ||
059ec3d9 PH |
1262 | |
1263 | /* Do the preparation for setting up a listener on one or more interfaces, and | |
1264 | possible on various ports. This is controlled by the combination of | |
1265 | local_interfaces (which can set IP addresses and ports) and daemon_smtp_port | |
1266 | (which is a list of default ports to use for those items in local_interfaces | |
1267 | that do not specify a port). The -oX command line option can be used to | |
1268 | override one or both of these options. | |
1269 | ||
1270 | If local_interfaces is not set, the default is to listen on all interfaces. | |
1271 | When it is set, it can include "all IPvx interfaces" as an item. This is useful | |
1272 | when different ports are in use. | |
1273 | ||
1274 | It turns out that listening on all interfaces is messy in an IPv6 world, | |
1275 | because several different implementation approaches have been taken. This code | |
1276 | is now supposed to work with all of them. The point of difference is whether an | |
1277 | IPv6 socket that is listening on all interfaces will receive incoming IPv4 | |
1278 | calls or not. We also have to cope with the case when IPv6 libraries exist, but | |
1279 | there is no IPv6 support in the kernel. | |
1280 | ||
1281 | . On Solaris, an IPv6 socket will accept IPv4 calls, and give them as mapped | |
1282 | addresses. However, if an IPv4 socket is also listening on all interfaces, | |
1283 | calls are directed to the appropriate socket. | |
1284 | ||
1285 | . On (some versions of) Linux, an IPv6 socket will accept IPv4 calls, and | |
1286 | give them as mapped addresses, but an attempt also to listen on an IPv4 | |
1287 | socket on all interfaces causes an error. | |
1288 | ||
1289 | . On OpenBSD, an IPv6 socket will not accept IPv4 calls. You have to set up | |
1290 | two sockets if you want to accept both kinds of call. | |
1291 | ||
1292 | . FreeBSD is like OpenBSD, but it has the IPV6_V6ONLY socket option, which | |
1293 | can be turned off, to make it behave like the versions of Linux described | |
1294 | above. | |
1295 | ||
1296 | . I heard a report that the USAGI IPv6 stack for Linux has implemented | |
1297 | IPV6_V6ONLY. | |
1298 | ||
1299 | So, what we do when IPv6 is supported is as follows: | |
1300 | ||
1301 | (1) After it is set up, the list of interfaces is scanned for wildcard | |
1302 | addresses. If an IPv6 and an IPv4 wildcard are both found for the same | |
1303 | port, the list is re-arranged so that they are together, with the IPv6 | |
1304 | wildcard first. | |
1305 | ||
1306 | (2) If the creation of a wildcard IPv6 socket fails, we just log the error and | |
1307 | carry on if an IPv4 wildcard socket for the same port follows later in the | |
1308 | list. This allows Exim to carry on in the case when the kernel has no IPv6 | |
1309 | support. | |
1310 | ||
1311 | (3) Having created an IPv6 wildcard socket, we try to set IPV6_V6ONLY if that | |
1312 | option is defined. However, if setting fails, carry on regardless (but log | |
1313 | the incident). | |
1314 | ||
1315 | (4) If binding or listening on an IPv6 wildcard socket fails, it is a serious | |
1316 | error. | |
1317 | ||
1318 | (5) If binding or listening on an IPv4 wildcard socket fails with the error | |
1319 | EADDRINUSE, and a previous interface was an IPv6 wildcard for the same | |
1320 | port (which must have succeeded or we wouldn't have got this far), we | |
1321 | assume we are in the situation where just a single socket is permitted, | |
1322 | and ignore the error. | |
1323 | ||
1324 | Phew! | |
1325 | ||
1326 | The preparation code decodes options and sets up the relevant data. We do this | |
1327 | first, so that we can return non-zero if there are any syntax errors, and also | |
1328 | write to stderr. */ | |
1329 | ||
8768d548 | 1330 | if (f.daemon_listen && !f.inetd_wait_mode) |
059ec3d9 PH |
1331 | { |
1332 | int *default_smtp_port; | |
1333 | int sep; | |
1334 | int pct = 0; | |
1335 | uschar *s; | |
55414b25 | 1336 | const uschar * list; |
059ec3d9 PH |
1337 | uschar *local_iface_source = US"local_interfaces"; |
1338 | ip_address_item *ipa; | |
1339 | ip_address_item **pipa; | |
1340 | ||
059ec3d9 PH |
1341 | /* If -oX was used, disable the writing of a pid file unless -oP was |
1342 | explicitly used to force it. Then scan the string given to -oX. Any items | |
1343 | that contain neither a dot nor a colon are used to override daemon_smtp_port. | |
1344 | Any other items are used to override local_interfaces. */ | |
1345 | ||
acec9514 | 1346 | if (override_local_interfaces) |
059ec3d9 | 1347 | { |
acec9514 JH |
1348 | gstring * new_smtp_port = NULL; |
1349 | gstring * new_local_interfaces = NULL; | |
059ec3d9 | 1350 | |
01446a56 | 1351 | if (!override_pid_file_path) write_pid = FALSE; |
059ec3d9 PH |
1352 | |
1353 | list = override_local_interfaces; | |
1354 | sep = 0; | |
ba74fb8d | 1355 | while ((s = string_nextinlist(&list, &sep, NULL, 0))) |
059ec3d9 PH |
1356 | { |
1357 | uschar joinstr[4]; | |
01446a56 | 1358 | gstring ** gp = Ustrpbrk(s, ".:") ? &new_local_interfaces : &new_smtp_port; |
059ec3d9 | 1359 | |
acec9514 | 1360 | if (!*gp) |
059ec3d9 PH |
1361 | { |
1362 | joinstr[0] = sep; | |
1363 | joinstr[1] = ' '; | |
acec9514 | 1364 | *gp = string_catn(*gp, US"<", 1); |
059ec3d9 PH |
1365 | } |
1366 | ||
acec9514 JH |
1367 | *gp = string_catn(*gp, joinstr, 2); |
1368 | *gp = string_cat (*gp, s); | |
059ec3d9 PH |
1369 | } |
1370 | ||
acec9514 | 1371 | if (new_smtp_port) |
059ec3d9 | 1372 | { |
acec9514 | 1373 | daemon_smtp_port = string_from_gstring(new_smtp_port); |
059ec3d9 PH |
1374 | DEBUG(D_any) debug_printf("daemon_smtp_port overridden by -oX:\n %s\n", |
1375 | daemon_smtp_port); | |
1376 | } | |
1377 | ||
acec9514 | 1378 | if (new_local_interfaces) |
059ec3d9 | 1379 | { |
acec9514 | 1380 | local_interfaces = string_from_gstring(new_local_interfaces); |
059ec3d9 PH |
1381 | local_iface_source = US"-oX data"; |
1382 | DEBUG(D_any) debug_printf("local_interfaces overridden by -oX:\n %s\n", | |
1383 | local_interfaces); | |
1384 | } | |
1385 | } | |
1386 | ||
1387 | /* Create a list of default SMTP ports, to be used if local_interfaces | |
4c04137d | 1388 | contains entries without explicit ports. First count the number of ports, then |
059ec3d9 PH |
1389 | build a translated list in a vector. */ |
1390 | ||
1391 | list = daemon_smtp_port; | |
1392 | sep = 0; | |
ba74fb8d | 1393 | while ((s = string_nextinlist(&list, &sep, NULL, 0))) |
059ec3d9 | 1394 | pct++; |
f3ebb786 | 1395 | default_smtp_port = store_get((pct+1) * sizeof(int), FALSE); |
059ec3d9 PH |
1396 | list = daemon_smtp_port; |
1397 | sep = 0; | |
1398 | for (pct = 0; | |
ba74fb8d | 1399 | (s = string_nextinlist(&list, &sep, NULL, 0)); |
059ec3d9 PH |
1400 | pct++) |
1401 | { | |
1402 | if (isdigit(*s)) | |
1403 | { | |
1404 | uschar *end; | |
1405 | default_smtp_port[pct] = Ustrtol(s, &end, 0); | |
1406 | if (end != s + Ustrlen(s)) | |
1407 | log_write(0, LOG_PANIC_DIE|LOG_CONFIG, "invalid SMTP port: %s", s); | |
1408 | } | |
1409 | else | |
1410 | { | |
1411 | struct servent *smtp_service = getservbyname(CS s, "tcp"); | |
071c51f7 | 1412 | if (!smtp_service) |
059ec3d9 PH |
1413 | log_write(0, LOG_PANIC_DIE|LOG_CONFIG, "TCP port \"%s\" not found", s); |
1414 | default_smtp_port[pct] = ntohs(smtp_service->s_port); | |
1415 | } | |
1416 | } | |
1417 | default_smtp_port[pct] = 0; | |
1418 | ||
071c51f7 JH |
1419 | /* Check the list of TLS-on-connect ports and do name lookups if needed */ |
1420 | ||
1421 | list = tls_in.on_connect_ports; | |
1422 | sep = 0; | |
1423 | while ((s = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))) | |
1424 | if (!isdigit(*s)) | |
1425 | { | |
acec9514 | 1426 | gstring * g = NULL; |
4226691b | 1427 | |
071c51f7 JH |
1428 | list = tls_in.on_connect_ports; |
1429 | tls_in.on_connect_ports = NULL; | |
1430 | sep = 0; | |
1431 | while ((s = string_nextinlist(&list, &sep, big_buffer, big_buffer_size))) | |
1432 | { | |
1433 | if (!isdigit(*s)) | |
1434 | { | |
4226691b | 1435 | struct servent * smtp_service = getservbyname(CS s, "tcp"); |
071c51f7 JH |
1436 | if (!smtp_service) |
1437 | log_write(0, LOG_PANIC_DIE|LOG_CONFIG, "TCP port \"%s\" not found", s); | |
4226691b | 1438 | s = string_sprintf("%d", (int)ntohs(smtp_service->s_port)); |
071c51f7 | 1439 | } |
acec9514 | 1440 | g = string_append_listele(g, ':', s); |
071c51f7 | 1441 | } |
acec9514 JH |
1442 | if (g) |
1443 | tls_in.on_connect_ports = g->s; | |
071c51f7 JH |
1444 | break; |
1445 | } | |
1446 | ||
059ec3d9 PH |
1447 | /* Create the list of local interfaces, possibly with ports included. This |
1448 | list may contain references to 0.0.0.0 and ::0 as wildcards. These special | |
1449 | values are converted below. */ | |
1450 | ||
1451 | addresses = host_build_ifacelist(local_interfaces, local_iface_source); | |
1452 | ||
1453 | /* In the list of IP addresses, convert 0.0.0.0 into an empty string, and ::0 | |
1454 | into the string ":". We use these to recognize wildcards in IPv4 and IPv6. In | |
1455 | fact, many IP stacks recognize 0.0.0.0 and ::0 and handle them as wildcards | |
1456 | anyway, but we need to know which are the wildcard addresses, and the shorter | |
1457 | strings are neater. | |
1458 | ||
1459 | In the same scan, fill in missing port numbers from the default list. When | |
1460 | there is more than one item in the list, extra items are created. */ | |
1461 | ||
b891534f | 1462 | for (ipa = addresses; ipa; ipa = ipa->next) |
059ec3d9 | 1463 | { |
b891534f JH |
1464 | if (Ustrcmp(ipa->address, "0.0.0.0") == 0) |
1465 | ipa->address[0] = 0; | |
059ec3d9 PH |
1466 | else if (Ustrcmp(ipa->address, "::0") == 0) |
1467 | { | |
1468 | ipa->address[0] = ':'; | |
1469 | ipa->address[1] = 0; | |
1470 | } | |
1471 | ||
1472 | if (ipa->port > 0) continue; | |
1473 | ||
1474 | if (daemon_smtp_port[0] <= 0) | |
1475 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "no port specified for interface " | |
1476 | "%s and daemon_smtp_port is unset; cannot start daemon", | |
b891534f JH |
1477 | ipa->address[0] == 0 ? US"\"all IPv4\"" : |
1478 | ipa->address[1] == 0 ? US"\"all IPv6\"" : ipa->address); | |
1479 | ||
059ec3d9 | 1480 | ipa->port = default_smtp_port[0]; |
d7978c0f | 1481 | for (int i = 1; default_smtp_port[i] > 0; i++) |
059ec3d9 | 1482 | { |
f3ebb786 | 1483 | ip_address_item *new = store_get(sizeof(ip_address_item), FALSE); |
b891534f | 1484 | |
059ec3d9 PH |
1485 | memcpy(new->address, ipa->address, Ustrlen(ipa->address) + 1); |
1486 | new->port = default_smtp_port[i]; | |
1487 | new->next = ipa->next; | |
1488 | ipa->next = new; | |
1489 | ipa = new; | |
1490 | } | |
1491 | } | |
1492 | ||
1493 | /* Scan the list of addresses for wildcards. If we find an IPv4 and an IPv6 | |
1494 | wildcard for the same port, ensure that (a) they are together and (b) the | |
1495 | IPv6 address comes first. This makes handling the messy features easier, and | |
1496 | also simplifies the construction of the "daemon started" log line. */ | |
1497 | ||
1498 | pipa = &addresses; | |
b891534f | 1499 | for (ipa = addresses; ipa; pipa = &ipa->next, ipa = ipa->next) |
059ec3d9 PH |
1500 | { |
1501 | ip_address_item *ipa2; | |
1502 | ||
1503 | /* Handle an IPv4 wildcard */ | |
1504 | ||
1505 | if (ipa->address[0] == 0) | |
b891534f | 1506 | for (ipa2 = ipa; ipa2->next; ipa2 = ipa2->next) |
059ec3d9 PH |
1507 | { |
1508 | ip_address_item *ipa3 = ipa2->next; | |
1509 | if (ipa3->address[0] == ':' && | |
1510 | ipa3->address[1] == 0 && | |
1511 | ipa3->port == ipa->port) | |
1512 | { | |
1513 | ipa2->next = ipa3->next; | |
1514 | ipa3->next = ipa; | |
1515 | *pipa = ipa3; | |
1516 | break; | |
1517 | } | |
1518 | } | |
059ec3d9 PH |
1519 | |
1520 | /* Handle an IPv6 wildcard. */ | |
1521 | ||
1522 | else if (ipa->address[0] == ':' && ipa->address[1] == 0) | |
b891534f | 1523 | for (ipa2 = ipa; ipa2->next; ipa2 = ipa2->next) |
059ec3d9 PH |
1524 | { |
1525 | ip_address_item *ipa3 = ipa2->next; | |
1526 | if (ipa3->address[0] == 0 && ipa3->port == ipa->port) | |
1527 | { | |
1528 | ipa2->next = ipa3->next; | |
1529 | ipa3->next = ipa->next; | |
1530 | ipa->next = ipa3; | |
1531 | ipa = ipa3; | |
1532 | break; | |
1533 | } | |
1534 | } | |
059ec3d9 PH |
1535 | } |
1536 | ||
1537 | /* Get a vector to remember all the sockets in */ | |
1538 | ||
b891534f | 1539 | for (ipa = addresses; ipa; ipa = ipa->next) |
059ec3d9 | 1540 | listen_socket_count++; |
f3ebb786 | 1541 | listen_sockets = store_get(sizeof(int) * listen_socket_count, FALSE); |
059ec3d9 | 1542 | |
9ee44efb PP |
1543 | } /* daemon_listen but not inetd_wait_mode */ |
1544 | ||
8768d548 | 1545 | if (f.daemon_listen) |
9ee44efb PP |
1546 | { |
1547 | ||
059ec3d9 PH |
1548 | /* Do a sanity check on the max connects value just to save us from getting |
1549 | a huge amount of store. */ | |
1550 | ||
1551 | if (smtp_accept_max > 4095) smtp_accept_max = 4096; | |
1552 | ||
1553 | /* There's no point setting smtp_accept_queue unless it is less than the max | |
1554 | connects limit. The configuration reader ensures that the max is set if the | |
1555 | queue-only option is set. */ | |
1556 | ||
1557 | if (smtp_accept_queue > smtp_accept_max) smtp_accept_queue = 0; | |
1558 | ||
1559 | /* Get somewhere to keep the list of SMTP accepting pids if we are keeping | |
1560 | track of them for total number and queue/host limits. */ | |
1561 | ||
1562 | if (smtp_accept_max > 0) | |
1563 | { | |
f3ebb786 | 1564 | smtp_slots = store_get(smtp_accept_max * sizeof(smtp_slot), FALSE); |
d7978c0f | 1565 | for (int i = 0; i < smtp_accept_max; i++) smtp_slots[i] = empty_smtp_slot; |
059ec3d9 PH |
1566 | } |
1567 | } | |
1568 | ||
76a2d7ba PH |
1569 | /* The variable background_daemon is always false when debugging, but |
1570 | can also be forced false in order to keep a non-debugging daemon in the | |
1571 | foreground. If background_daemon is true, close all open file descriptors that | |
9ee44efb PP |
1572 | we know about, but then re-open stdin, stdout, and stderr to /dev/null. Also |
1573 | do this for inetd_wait mode. | |
76a2d7ba PH |
1574 | |
1575 | This is protection against any called functions (in libraries, or in | |
1576 | Perl, or whatever) that think they can write to stderr (or stdout). Before this | |
1577 | was added, it was quite likely that an SMTP connection would use one of these | |
1578 | file descriptors, in which case writing random stuff to it caused chaos. | |
1579 | ||
1580 | Then disconnect from the controlling terminal, Most modern Unixes seem to have | |
1581 | setsid() for getting rid of the controlling terminal. For any OS that doesn't, | |
1582 | setsid() can be #defined as a no-op, or as something else. */ | |
059ec3d9 | 1583 | |
8768d548 | 1584 | if (f.background_daemon || f.inetd_wait_mode) |
059ec3d9 | 1585 | { |
76a2d7ba PH |
1586 | log_close_all(); /* Just in case anything was logged earlier */ |
1587 | search_tidyup(); /* Just in case any were used in reading the config. */ | |
f1e894f3 PH |
1588 | (void)close(0); /* Get rid of stdin/stdout/stderr */ |
1589 | (void)close(1); | |
1590 | (void)close(2); | |
8e669ac1 | 1591 | exim_nullstd(); /* Connect stdin/stdout/stderr to /dev/null */ |
059ec3d9 | 1592 | log_stderr = NULL; /* So no attempt to copy paniclog output */ |
9ee44efb | 1593 | } |
059ec3d9 | 1594 | |
8768d548 | 1595 | if (f.background_daemon) |
9ee44efb | 1596 | { |
059ec3d9 | 1597 | /* If the parent process of this one has pid == 1, we are re-initializing the |
8e669ac1 | 1598 | daemon as the result of a SIGHUP. In this case, there is no need to do |
76a2d7ba PH |
1599 | anything, because the controlling terminal has long gone. Otherwise, fork, in |
1600 | case current process is a process group leader (see 'man setsid' for an | |
1601 | explanation) before calling setsid(). */ | |
059ec3d9 PH |
1602 | |
1603 | if (getppid() != 1) | |
1604 | { | |
8e9fdd63 | 1605 | pid_t pid = exim_fork(US"daemon"); |
059ec3d9 PH |
1606 | if (pid < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
1607 | "fork() failed when starting daemon: %s", strerror(errno)); | |
1608 | if (pid > 0) exit(EXIT_SUCCESS); /* in parent process, just exit */ | |
1609 | (void)setsid(); /* release controlling terminal */ | |
1610 | } | |
1611 | } | |
1612 | ||
1613 | /* We are now in the disconnected, daemon process (unless debugging). Set up | |
1614 | the listening sockets if required. */ | |
1615 | ||
4c2efd7a | 1616 | daemon_notifier_socket(); |
ff966302 | 1617 | |
8768d548 | 1618 | if (f.daemon_listen && !f.inetd_wait_mode) |
059ec3d9 PH |
1619 | { |
1620 | int sk; | |
059ec3d9 PH |
1621 | ip_address_item *ipa; |
1622 | ||
1623 | /* For each IP address, create a socket, bind it to the appropriate port, and | |
1624 | start listening. See comments above about IPv6 sockets that may or may not | |
1625 | accept IPv4 calls when listening on all interfaces. We also have to cope with | |
1626 | the case of a system with IPv6 libraries, but no IPv6 support in the kernel. | |
1627 | listening, provided a wildcard IPv4 socket for the same port follows. */ | |
1628 | ||
1629 | for (ipa = addresses, sk = 0; sk < listen_socket_count; ipa = ipa->next, sk++) | |
1630 | { | |
1631 | BOOL wildcard; | |
1632 | ip_address_item *ipa2; | |
059ec3d9 PH |
1633 | int af; |
1634 | ||
1635 | if (Ustrchr(ipa->address, ':') != NULL) | |
1636 | { | |
1637 | af = AF_INET6; | |
1638 | wildcard = ipa->address[1] == 0; | |
1639 | } | |
1640 | else | |
1641 | { | |
1642 | af = AF_INET; | |
1643 | wildcard = ipa->address[0] == 0; | |
1644 | } | |
1645 | ||
96f5fe4c | 1646 | if ((listen_sockets[sk] = ip_socket(SOCK_STREAM, af)) < 0) |
059ec3d9 PH |
1647 | { |
1648 | if (check_special_case(0, addresses, ipa, FALSE)) | |
1649 | { | |
1650 | log_write(0, LOG_MAIN, "Failed to create IPv6 socket for wildcard " | |
1651 | "listening (%s): will use IPv4", strerror(errno)); | |
1652 | goto SKIP_SOCKET; | |
1653 | } | |
1654 | log_write(0, LOG_PANIC_DIE, "IPv%c socket creation failed: %s", | |
1655 | (af == AF_INET6)? '6' : '4', strerror(errno)); | |
1656 | } | |
1657 | ||
1658 | /* If this is an IPv6 wildcard socket, set IPV6_V6ONLY if that option is | |
1659 | available. Just log failure (can get protocol not available, just like | |
1660 | socket creation can). */ | |
1661 | ||
b891534f | 1662 | #ifdef IPV6_V6ONLY |
059ec3d9 | 1663 | if (af == AF_INET6 && wildcard && |
5903c6ff | 1664 | setsockopt(listen_sockets[sk], IPPROTO_IPV6, IPV6_V6ONLY, CS (&on), |
059ec3d9 PH |
1665 | sizeof(on)) < 0) |
1666 | log_write(0, LOG_MAIN, "Setting IPV6_V6ONLY on daemon's IPv6 wildcard " | |
1667 | "socket failed (%s): carrying on without it", strerror(errno)); | |
b891534f | 1668 | #endif /* IPV6_V6ONLY */ |
059ec3d9 PH |
1669 | |
1670 | /* Set SO_REUSEADDR so that the daemon can be restarted while a connection | |
1671 | is being handled. Without this, a connection will prevent reuse of the | |
1672 | smtp port for listening. */ | |
1673 | ||
1674 | if (setsockopt(listen_sockets[sk], SOL_SOCKET, SO_REUSEADDR, | |
5903c6ff | 1675 | US (&on), sizeof(on)) < 0) |
059ec3d9 PH |
1676 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "setting SO_REUSEADDR on socket " |
1677 | "failed when starting daemon: %s", strerror(errno)); | |
1678 | ||
1679 | /* Set TCP_NODELAY; Exim does its own buffering. There is a switch to | |
1680 | disable this because it breaks some broken clients. */ | |
1681 | ||
1682 | if (tcp_nodelay) setsockopt(listen_sockets[sk], IPPROTO_TCP, TCP_NODELAY, | |
5903c6ff | 1683 | US (&on), sizeof(on)); |
059ec3d9 PH |
1684 | |
1685 | /* Now bind the socket to the required port; if Exim is being restarted | |
1686 | it may not always be possible to bind immediately, even with SO_REUSEADDR | |
1687 | set, so try 10 times, waiting between each try. After 10 failures, we give | |
1688 | up. In an IPv6 environment, if bind () fails with the error EADDRINUSE and | |
1689 | we are doing wildcard IPv4 listening and there was a previous IPv6 wildcard | |
1690 | address for the same port, ignore the error on the grounds that we must be | |
1691 | in a system where the IPv6 socket accepts both kinds of call. This is | |
1692 | necessary for (some release of) USAGI Linux; other IP stacks fail at the | |
1693 | listen() stage instead. */ | |
1694 | ||
6af7e591 | 1695 | #ifdef TCP_FASTOPEN |
8768d548 | 1696 | f.tcp_fastopen_ok = TRUE; |
6af7e591 | 1697 | #endif |
059ec3d9 PH |
1698 | for(;;) |
1699 | { | |
1700 | uschar *msg, *addr; | |
1701 | if (ip_bind(listen_sockets[sk], af, ipa->address, ipa->port) >= 0) break; | |
1702 | if (check_special_case(errno, addresses, ipa, TRUE)) | |
1703 | { | |
1704 | DEBUG(D_any) debug_printf("wildcard IPv4 bind() failed after IPv6 " | |
1705 | "listen() success; EADDRINUSE ignored\n"); | |
f1e894f3 | 1706 | (void)close(listen_sockets[sk]); |
059ec3d9 PH |
1707 | goto SKIP_SOCKET; |
1708 | } | |
1709 | msg = US strerror(errno); | |
b891534f JH |
1710 | addr = wildcard |
1711 | ? af == AF_INET6 | |
1712 | ? US"(any IPv6)" | |
1713 | : US"(any IPv4)" | |
1714 | : ipa->address; | |
4aee0225 | 1715 | if (daemon_startup_retries <= 0) |
059ec3d9 PH |
1716 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
1717 | "socket bind() to port %d for address %s failed: %s: " | |
1718 | "daemon abandoned", ipa->port, addr, msg); | |
1719 | log_write(0, LOG_MAIN, "socket bind() to port %d for address %s " | |
4aee0225 PH |
1720 | "failed: %s: waiting %s before trying again (%d more %s)", |
1721 | ipa->port, addr, msg, readconf_printtime(daemon_startup_sleep), | |
1722 | daemon_startup_retries, (daemon_startup_retries > 1)? "tries" : "try"); | |
1723 | daemon_startup_retries--; | |
1724 | sleep(daemon_startup_sleep); | |
059ec3d9 PH |
1725 | } |
1726 | ||
1727 | DEBUG(D_any) | |
059ec3d9 PH |
1728 | if (wildcard) |
1729 | debug_printf("listening on all interfaces (IPv%c) port %d\n", | |
fb05276a | 1730 | af == AF_INET6 ? '6' : '4', ipa->port); |
059ec3d9 PH |
1731 | else |
1732 | debug_printf("listening on %s port %d\n", ipa->address, ipa->port); | |
fb05276a | 1733 | |
b536a578 | 1734 | #if defined(TCP_FASTOPEN) && !defined(__APPLE__) |
590faf89 JH |
1735 | if ( f.tcp_fastopen_ok |
1736 | && setsockopt(listen_sockets[sk], IPPROTO_TCP, TCP_FASTOPEN, | |
4670e9d3 | 1737 | &smtp_connect_backlog, sizeof(smtp_connect_backlog))) |
6af7e591 | 1738 | { |
a23ff3b4 | 1739 | DEBUG(D_any) debug_printf("setsockopt FASTOPEN: %s\n", strerror(errno)); |
8768d548 | 1740 | f.tcp_fastopen_ok = FALSE; |
6af7e591 | 1741 | } |
fb05276a | 1742 | #endif |
059ec3d9 PH |
1743 | |
1744 | /* Start listening on the bound socket, establishing the maximum backlog of | |
1745 | connections that is allowed. On success, continue to the next address. */ | |
1746 | ||
b536a578 JH |
1747 | if (listen(listen_sockets[sk], smtp_connect_backlog) >= 0) |
1748 | { | |
1749 | #if defined(TCP_FASTOPEN) && defined(__APPLE__) | |
1750 | if ( f.tcp_fastopen_ok | |
1751 | && setsockopt(listen_sockets[sk], IPPROTO_TCP, TCP_FASTOPEN, | |
1752 | &on, sizeof(on))) | |
1753 | { | |
1754 | DEBUG(D_any) debug_printf("setsockopt FASTOPEN: %s\n", strerror(errno)); | |
1755 | f.tcp_fastopen_ok = FALSE; | |
1756 | } | |
1757 | #endif | |
1758 | continue; | |
1759 | } | |
059ec3d9 PH |
1760 | |
1761 | /* Listening has failed. In an IPv6 environment, as for bind(), if listen() | |
1762 | fails with the error EADDRINUSE and we are doing IPv4 wildcard listening | |
1763 | and there was a previous successful IPv6 wildcard listen on the same port, | |
1764 | we want to ignore the error on the grounds that we must be in a system | |
1765 | where the IPv6 socket accepts both kinds of call. */ | |
1766 | ||
1767 | if (!check_special_case(errno, addresses, ipa, TRUE)) | |
1768 | log_write(0, LOG_PANIC_DIE, "listen() failed on interface %s: %s", | |
fb05276a JH |
1769 | wildcard |
1770 | ? af == AF_INET6 ? US"(any IPv6)" : US"(any IPv4)" : ipa->address, | |
059ec3d9 PH |
1771 | strerror(errno)); |
1772 | ||
1773 | DEBUG(D_any) debug_printf("wildcard IPv4 listen() failed after IPv6 " | |
1774 | "listen() success; EADDRINUSE ignored\n"); | |
f1e894f3 | 1775 | (void)close(listen_sockets[sk]); |
059ec3d9 PH |
1776 | |
1777 | /* Come here if there has been a problem with the socket which we | |
1778 | are going to ignore. We remove the address from the chain, and back up the | |
1779 | counts. */ | |
1780 | ||
b891534f | 1781 | SKIP_SOCKET: |
059ec3d9 PH |
1782 | sk--; /* Back up the count */ |
1783 | listen_socket_count--; /* Reduce the total */ | |
1784 | if (ipa == addresses) addresses = ipa->next; else | |
1785 | { | |
1786 | for (ipa2 = addresses; ipa2->next != ipa; ipa2 = ipa2->next); | |
1787 | ipa2->next = ipa->next; | |
1788 | ipa = ipa2; | |
1789 | } | |
1790 | } /* End of bind/listen loop for each address */ | |
1791 | } /* End of setup for listening */ | |
1792 | ||
1793 | ||
1794 | /* If we are not listening, we want to write a pid file only if -oP was | |
1795 | explicitly given. */ | |
1796 | ||
b891534f JH |
1797 | else if (!override_pid_file_path) |
1798 | write_pid = FALSE; | |
059ec3d9 PH |
1799 | |
1800 | /* Write the pid to a known file for assistance in identification, if required. | |
1801 | We do this before giving up root privilege, because on some systems it is | |
1802 | necessary to be root in order to write into the pid file directory. There's | |
1803 | nothing to stop multiple daemons running, as long as no more than one listens | |
1804 | on a given TCP/IP port on the same interface(s). However, in these | |
1805 | circumstances it gets far too complicated to mess with pid file names | |
1806 | automatically. Consequently, Exim 4 writes a pid file only | |
1807 | ||
1808 | (a) When running in the test harness, or | |
1809 | (b) When -bd is used and -oX is not used, or | |
1810 | (c) When -oP is used to supply a path. | |
1811 | ||
1812 | The variable daemon_write_pid is used to control this. */ | |
1813 | ||
8768d548 | 1814 | if (f.running_in_test_harness || write_pid) |
059ec3d9 PH |
1815 | { |
1816 | FILE *f; | |
1817 | ||
01446a56 | 1818 | set_pid_file_path(); |
b891534f | 1819 | if ((f = modefopen(pid_file_path, "wb", 0644))) |
059ec3d9 | 1820 | { |
ff790e47 | 1821 | (void)fprintf(f, "%d\n", (int)getpid()); |
ff790e47 | 1822 | (void)fclose(f); |
059ec3d9 PH |
1823 | DEBUG(D_any) debug_printf("pid written to %s\n", pid_file_path); |
1824 | } | |
1825 | else | |
059ec3d9 PH |
1826 | DEBUG(D_any) |
1827 | debug_printf("%s\n", string_open_failed(errno, "pid file %s", | |
1828 | pid_file_path)); | |
059ec3d9 PH |
1829 | } |
1830 | ||
1831 | /* Set up the handler for SIGHUP, which causes a restart of the daemon. */ | |
1832 | ||
1833 | sighup_seen = FALSE; | |
1834 | signal(SIGHUP, sighup_handler); | |
1835 | ||
1836 | /* Give up root privilege at this point (assuming that exim_uid and exim_gid | |
1837 | are not root). The third argument controls the running of initgroups(). | |
1838 | Normally we do this, in order to set up the groups for the Exim user. However, | |
1839 | if we are not root at this time - some odd installations run that way - we | |
1840 | cannot do this. */ | |
1841 | ||
1842 | exim_setugid(exim_uid, exim_gid, geteuid()==root_uid, US"running as a daemon"); | |
1843 | ||
ebeaf996 PH |
1844 | /* Update the originator_xxx fields so that received messages as listed as |
1845 | coming from Exim, not whoever started the daemon. */ | |
1846 | ||
1847 | originator_uid = exim_uid; | |
1848 | originator_gid = exim_gid; | |
f3ebb786 JH |
1849 | originator_login = (pw = getpwuid(exim_uid)) |
1850 | ? string_copy_perm(US pw->pw_name, FALSE) : US"exim"; | |
ebeaf996 | 1851 | |
059ec3d9 PH |
1852 | /* Get somewhere to keep the list of queue-runner pids if we are keeping track |
1853 | of them (and also if we are doing queue runs). */ | |
1854 | ||
0cd5fd23 | 1855 | if (queue_interval > 0 && local_queue_run_max > 0) |
059ec3d9 | 1856 | { |
f3ebb786 | 1857 | queue_pid_slots = store_get(local_queue_run_max * sizeof(pid_t), FALSE); |
d7978c0f | 1858 | for (int i = 0; i < local_queue_run_max; i++) queue_pid_slots[i] = 0; |
059ec3d9 PH |
1859 | } |
1860 | ||
01446a56 JH |
1861 | /* Set up the handler for termination of child processes, and the one |
1862 | telling us to die. */ | |
059ec3d9 PH |
1863 | |
1864 | sigchld_seen = FALSE; | |
7d468ab8 | 1865 | os_non_restarting_signal(SIGCHLD, main_sigchld_handler); |
059ec3d9 | 1866 | |
01446a56 JH |
1867 | sigterm_seen = FALSE; |
1868 | os_non_restarting_signal(SIGTERM, main_sigterm_handler); | |
1869 | ||
059ec3d9 PH |
1870 | /* If we are to run the queue periodically, pretend the alarm has just gone |
1871 | off. This will cause the first queue-runner to get kicked off straight away. */ | |
1872 | ||
1873 | sigalrm_seen = (queue_interval > 0); | |
1874 | ||
1875 | /* Log the start up of a daemon - at least one of listening or queue running | |
1876 | must be set up. */ | |
1877 | ||
8768d548 | 1878 | if (f.inetd_wait_mode) |
9ee44efb PP |
1879 | { |
1880 | uschar *p = big_buffer; | |
1881 | ||
1882 | if (inetd_wait_timeout >= 0) | |
1883 | sprintf(CS p, "terminating after %d seconds", inetd_wait_timeout); | |
1884 | else | |
1885 | sprintf(CS p, "with no wait timeout"); | |
1886 | ||
1887 | log_write(0, LOG_MAIN, | |
1888 | "exim %s daemon started: pid=%d, launched with listening socket, %s", | |
1889 | version_string, getpid(), big_buffer); | |
2f21487f | 1890 | set_process_info("daemon(%s): pre-listening socket", version_string); |
9ee44efb PP |
1891 | |
1892 | /* set up the timeout logic */ | |
ff966302 | 1893 | sigalrm_seen = TRUE; |
9ee44efb PP |
1894 | } |
1895 | ||
8768d548 | 1896 | else if (f.daemon_listen) |
059ec3d9 | 1897 | { |
059ec3d9 PH |
1898 | int smtp_ports = 0; |
1899 | int smtps_ports = 0; | |
254f38d1 JH |
1900 | ip_address_item * ipa; |
1901 | uschar * p; | |
e37f8a84 | 1902 | uschar * qinfo = queue_interval > 0 |
173de73b JH |
1903 | ? string_sprintf("-q%s%s", |
1904 | f.queue_2stage ? "q" : "", readconf_printtime(queue_interval)) | |
e37f8a84 | 1905 | : US"no queue runs"; |
059ec3d9 PH |
1906 | |
1907 | /* Build a list of listening addresses in big_buffer, but limit it to 10 | |
1908 | items. The style is for backwards compatibility. | |
1909 | ||
1910 | It is now possible to have some ports listening for SMTPS (the old, | |
1911 | deprecated protocol that starts TLS without using STARTTLS), and others | |
1912 | listening for standard SMTP. Keep their listings separate. */ | |
1913 | ||
254f38d1 | 1914 | for (int j = 0, i; j < 2; j++) |
059ec3d9 | 1915 | { |
e37f8a84 | 1916 | for (i = 0, ipa = addresses; i < 10 && ipa; i++, ipa = ipa->next) |
b891534f JH |
1917 | { |
1918 | /* First time round, look for SMTP ports; second time round, look for | |
254f38d1 | 1919 | SMTPS ports. Build IP+port strings. */ |
b891534f JH |
1920 | |
1921 | if (host_is_tls_on_connect_port(ipa->port) == (j > 0)) | |
1922 | { | |
1923 | if (j == 0) | |
254f38d1 | 1924 | smtp_ports++; |
b891534f | 1925 | else |
254f38d1 | 1926 | smtps_ports++; |
b891534f JH |
1927 | |
1928 | /* Now the information about the port (and sometimes interface) */ | |
1929 | ||
1930 | if (ipa->address[0] == ':' && ipa->address[1] == 0) | |
e4d0fc93 | 1931 | { /* v6 wildcard */ |
b891534f JH |
1932 | if (ipa->next && ipa->next->address[0] == 0 && |
1933 | ipa->next->port == ipa->port) | |
1934 | { | |
254f38d1 JH |
1935 | ipa->log = string_sprintf(" port %d (IPv6 and IPv4)", ipa->port); |
1936 | (ipa = ipa->next)->log = NULL; | |
b891534f JH |
1937 | } |
1938 | else if (ipa->v6_include_v4) | |
254f38d1 | 1939 | ipa->log = string_sprintf(" port %d (IPv6 with IPv4)", ipa->port); |
b891534f | 1940 | else |
254f38d1 | 1941 | ipa->log = string_sprintf(" port %d (IPv6)", ipa->port); |
b891534f | 1942 | } |
e4d0fc93 | 1943 | else if (ipa->address[0] == 0) /* v4 wildcard */ |
254f38d1 | 1944 | ipa->log = string_sprintf(" port %d (IPv4)", ipa->port); |
e4d0fc93 | 1945 | else /* check for previously-seen IP */ |
b891534f | 1946 | { |
254f38d1 | 1947 | ip_address_item * i2; |
e4d0fc93 JH |
1948 | for (i2 = addresses; i2 != ipa; i2 = i2->next) |
1949 | if ( host_is_tls_on_connect_port(i2->port) == (j > 0) | |
1950 | && Ustrcmp(ipa->address, i2->address) == 0 | |
1951 | ) | |
1952 | { /* found; append port to list */ | |
254f38d1 JH |
1953 | for (p = i2->log; *p; ) p++; /* end of existing string */ |
1954 | if (*--p == '}') *p = '\0'; /* drop EOL */ | |
1955 | while (isdigit(*--p)) ; /* char before port */ | |
1956 | ||
1957 | i2->log = *p == ':' /* no list yet? */ | |
1958 | ? string_sprintf("%.*s{%s,%d}", | |
1959 | (int)(p - i2->log + 1), i2->log, p+1, ipa->port) | |
1960 | : string_sprintf("%s,%d}", i2->log, ipa->port); | |
1961 | ipa->log = NULL; | |
e4d0fc93 JH |
1962 | break; |
1963 | } | |
1964 | if (i2 == ipa) /* first-time IP */ | |
254f38d1 | 1965 | ipa->log = string_sprintf(" [%s]:%d", ipa->address, ipa->port); |
b891534f | 1966 | } |
b891534f JH |
1967 | } |
1968 | } | |
254f38d1 | 1969 | } |
059ec3d9 | 1970 | |
254f38d1 JH |
1971 | p = big_buffer; |
1972 | for (int j = 0, i; j < 2; j++) | |
1973 | { | |
1974 | /* First time round, look for SMTP ports; second time round, look for | |
1975 | SMTPS ports. For the first one of each, insert leading text. */ | |
1976 | ||
1977 | if (j == 0) | |
059ec3d9 | 1978 | { |
254f38d1 JH |
1979 | if (smtp_ports > 0) |
1980 | p += sprintf(CS p, "SMTP on"); | |
059ec3d9 | 1981 | } |
254f38d1 JH |
1982 | else |
1983 | if (smtps_ports > 0) | |
1984 | p += sprintf(CS p, "%sSMTPS on", | |
1985 | smtp_ports == 0 ? "" : " and for "); | |
1986 | ||
1987 | /* Now the information about the port (and sometimes interface) */ | |
1988 | ||
1989 | for (i = 0, ipa = addresses; i < 10 && ipa; i++, ipa = ipa->next) | |
1990 | if (host_is_tls_on_connect_port(ipa->port) == (j > 0)) | |
1991 | if (ipa->log) | |
1992 | p += sprintf(CS p, "%s", ipa->log); | |
1993 | ||
1994 | if (ipa) | |
1995 | p += sprintf(CS p, " ..."); | |
059ec3d9 PH |
1996 | } |
1997 | ||
1998 | log_write(0, LOG_MAIN, | |
1999 | "exim %s daemon started: pid=%d, %s, listening for %s", | |
2000 | version_string, getpid(), qinfo, big_buffer); | |
44915474 JH |
2001 | set_process_info("daemon(%s): %s, listening for %s", |
2002 | version_string, qinfo, big_buffer); | |
059ec3d9 PH |
2003 | } |
2004 | ||
2005 | else | |
2006 | { | |
44915474 JH |
2007 | uschar * s = *queue_name |
2008 | ? string_sprintf("-qG%s/%s", queue_name, readconf_printtime(queue_interval)) | |
2009 | : string_sprintf("-q%s", readconf_printtime(queue_interval)); | |
059ec3d9 | 2010 | log_write(0, LOG_MAIN, |
44915474 JH |
2011 | "exim %s daemon started: pid=%d, %s, not listening for SMTP", |
2012 | version_string, getpid(), s); | |
2013 | set_process_info("daemon(%s): %s, not listening", version_string, s); | |
059ec3d9 PH |
2014 | } |
2015 | ||
476be7e2 JH |
2016 | /* Do any work it might be useful to amortize over our children |
2017 | (eg: compile regex) */ | |
2018 | ||
476be7e2 | 2019 | dns_pattern_init(); |
d85cdeb5 JH |
2020 | smtp_deliver_init(); /* Used for callouts */ |
2021 | ||
2022 | #ifndef DISABLE_DKIM | |
2023 | { | |
2024 | # ifdef MEASURE_TIMING | |
2025 | struct timeval t0; | |
2026 | gettimeofday(&t0, NULL); | |
2027 | # endif | |
2028 | dkim_exim_init(); | |
2029 | # ifdef MEASURE_TIMING | |
2030 | report_time_since(&t0, US"dkim_exim_init (delta)"); | |
2031 | # endif | |
2032 | } | |
2033 | #endif | |
476be7e2 JH |
2034 | |
2035 | #ifdef WITH_CONTENT_SCAN | |
2036 | malware_init(); | |
2037 | #endif | |
73ec116f JH |
2038 | #ifdef SUPPORT_SPF |
2039 | spf_init(); | |
2040 | #endif | |
059ec3d9 PH |
2041 | |
2042 | /* Close the log so it can be renamed and moved. In the few cases below where | |
2043 | this long-running process writes to the log (always exceptional conditions), it | |
2044 | closes the log afterwards, for the same reason. */ | |
2045 | ||
2046 | log_close_all(); | |
2047 | ||
2048 | DEBUG(D_any) debug_print_ids(US"daemon running with"); | |
2049 | ||
2050 | /* Any messages accepted via this route are going to be SMTP. */ | |
2051 | ||
2052 | smtp_input = TRUE; | |
2053 | ||
9f01e50d JH |
2054 | #ifdef MEASURE_TIMING |
2055 | report_time_since(×tamp_startup, US"daemon loop start"); /* testcase 0022 */ | |
2056 | #endif | |
2057 | ||
059ec3d9 PH |
2058 | /* Enter the never-ending loop... */ |
2059 | ||
2060 | for (;;) | |
2061 | { | |
2062 | #if HAVE_IPV6 | |
2063 | struct sockaddr_in6 accepted; | |
2064 | #else | |
2065 | struct sockaddr_in accepted; | |
2066 | #endif | |
2067 | ||
cf73943b | 2068 | EXIM_SOCKLEN_T len; |
059ec3d9 PH |
2069 | pid_t pid; |
2070 | ||
01446a56 JH |
2071 | if (sigterm_seen) |
2072 | daemon_die(); /* Does not return */ | |
2073 | ||
059ec3d9 | 2074 | /* This code is placed first in the loop, so that it gets obeyed at the |
9ee44efb PP |
2075 | start, before the first wait, for the queue-runner case, so that the first |
2076 | one can be started immediately. | |
2077 | ||
2078 | The other option is that we have an inetd wait timeout specified to -bw. */ | |
059ec3d9 PH |
2079 | |
2080 | if (sigalrm_seen) | |
2081 | { | |
9ee44efb PP |
2082 | if (inetd_wait_timeout > 0) |
2083 | { | |
2084 | time_t resignal_interval = inetd_wait_timeout; | |
2085 | ||
2086 | if (last_connection_time == (time_t)0) | |
2087 | { | |
2088 | DEBUG(D_any) | |
2089 | debug_printf("inetd wait timeout expired, but still not seen first message, ignoring\n"); | |
2090 | } | |
2091 | else | |
2092 | { | |
2093 | time_t now = time(NULL); | |
2094 | if (now == (time_t)-1) | |
2095 | { | |
2096 | DEBUG(D_any) debug_printf("failed to get time: %s\n", strerror(errno)); | |
2097 | } | |
2098 | else | |
2099 | { | |
2100 | if ((now - last_connection_time) >= inetd_wait_timeout) | |
2101 | { | |
2102 | DEBUG(D_any) | |
2103 | debug_printf("inetd wait timeout %d expired, ending daemon\n", | |
2104 | inetd_wait_timeout); | |
2105 | log_write(0, LOG_MAIN, "exim %s daemon terminating, inetd wait timeout reached.\n", | |
2106 | version_string); | |
2107 | exit(EXIT_SUCCESS); | |
2108 | } | |
2109 | else | |
2110 | { | |
2111 | resignal_interval -= (now - last_connection_time); | |
2112 | } | |
2113 | } | |
2114 | } | |
059ec3d9 | 2115 | |
9ee44efb | 2116 | sigalrm_seen = FALSE; |
c2a1bba0 | 2117 | ALARM(resignal_interval); |
9ee44efb | 2118 | } |
059ec3d9 | 2119 | |
9ee44efb | 2120 | else |
059ec3d9 | 2121 | { |
ff966302 JH |
2122 | DEBUG(D_any) debug_printf("%s received\n", |
2123 | #ifdef EXPERIMENTAL_QUEUE_RAMP | |
2124 | *queuerun_msgid ? "qrun notification" : | |
2125 | #endif | |
2126 | "SIGALRM"); | |
8e669ac1 | 2127 | |
9ee44efb PP |
2128 | /* Do a full queue run in a child process, if required, unless we already |
2129 | have enough queue runners on the go. If we are not running as root, a | |
2130 | re-exec is required. */ | |
059ec3d9 | 2131 | |
96c81511 JH |
2132 | if ( queue_interval > 0 |
2133 | && (local_queue_run_max <= 0 || queue_run_count < local_queue_run_max)) | |
9ee44efb | 2134 | { |
4b01271f | 2135 | if ((pid = exim_fork(US"queue-runner")) == 0) |
9ee44efb | 2136 | { |
9ee44efb PP |
2137 | /* Disable debugging if it's required only for the daemon process. We |
2138 | leave the above message, because it ties up with the "child ended" | |
2139 | debugging messages. */ | |
059ec3d9 | 2140 | |
8768d548 | 2141 | if (f.debug_daemon) debug_selector = 0; |
059ec3d9 | 2142 | |
9ee44efb | 2143 | /* Close any open listening sockets in the child */ |
059ec3d9 | 2144 | |
8cfc4d82 JH |
2145 | close_daemon_sockets(daemon_notifier_fd, |
2146 | listen_sockets, listen_socket_count); | |
059ec3d9 | 2147 | |
9ee44efb | 2148 | /* Reset SIGHUP and SIGCHLD in the child in both cases. */ |
059ec3d9 | 2149 | |
9ee44efb PP |
2150 | signal(SIGHUP, SIG_DFL); |
2151 | signal(SIGCHLD, SIG_DFL); | |
01446a56 | 2152 | signal(SIGTERM, SIG_DFL); |
059ec3d9 | 2153 | |
9ee44efb PP |
2154 | /* Re-exec if privilege has been given up, unless deliver_drop_ |
2155 | privilege is set. Reset SIGALRM before exec(). */ | |
4fbcfc2e | 2156 | |
9ee44efb | 2157 | if (geteuid() != root_uid && !deliver_drop_privilege) |
4fbcfc2e | 2158 | { |
9ee44efb PP |
2159 | uschar opt[8]; |
2160 | uschar *p = opt; | |
ff966302 | 2161 | uschar *extra[7]; |
9ee44efb PP |
2162 | int extracount = 1; |
2163 | ||
2164 | signal(SIGALRM, SIG_DFL); | |
2165 | *p++ = '-'; | |
2166 | *p++ = 'q'; | |
ff966302 JH |
2167 | if ( f.queue_2stage |
2168 | #ifdef EXPERIMENTAL_QUEUE_RAMP | |
2169 | && !*queuerun_msgid | |
2170 | #endif | |
2171 | ) *p++ = 'q'; | |
8768d548 JH |
2172 | if (f.queue_run_first_delivery) *p++ = 'i'; |
2173 | if (f.queue_run_force) *p++ = 'f'; | |
2174 | if (f.deliver_force_thaw) *p++ = 'f'; | |
2175 | if (f.queue_run_local) *p++ = 'l'; | |
9ee44efb | 2176 | *p = 0; |
3f008c60 | 2177 | extra[0] = *queue_name |
e37f8a84 | 2178 | ? string_sprintf("%sG%s", opt, queue_name) : opt; |
9ee44efb | 2179 | |
ff966302 JH |
2180 | #ifdef EXPERIMENTAL_QUEUE_RAMP |
2181 | if (*queuerun_msgid) | |
2182 | { | |
6641ba45 | 2183 | log_write(0, LOG_MAIN, "notify triggered queue run"); |
ff966302 JH |
2184 | extra[extracount++] = queuerun_msgid; /* Trigger only the */ |
2185 | extra[extracount++] = queuerun_msgid; /* one message */ | |
2186 | } | |
2187 | #endif | |
2188 | ||
9ee44efb PP |
2189 | /* If -R or -S were on the original command line, ensure they get |
2190 | passed on. */ | |
2191 | ||
e37f8a84 | 2192 | if (deliver_selectstring) |
9ee44efb | 2193 | { |
8768d548 | 2194 | extra[extracount++] = f.deliver_selectstring_regex ? US"-Rr" : US"-R"; |
9ee44efb PP |
2195 | extra[extracount++] = deliver_selectstring; |
2196 | } | |
2197 | ||
e37f8a84 | 2198 | if (deliver_selectstring_sender) |
9ee44efb | 2199 | { |
8768d548 | 2200 | extra[extracount++] = f.deliver_selectstring_sender_regex |
e37f8a84 | 2201 | ? US"-Sr" : US"-S"; |
9ee44efb PP |
2202 | extra[extracount++] = deliver_selectstring_sender; |
2203 | } | |
2204 | ||
2205 | /* Overlay this process with a new execution. */ | |
2206 | ||
ff966302 JH |
2207 | (void)child_exec_exim(CEE_EXEC_PANIC, FALSE, NULL, FALSE, extracount, |
2208 | extra[0], extra[1], extra[2], extra[3], extra[4], extra[5], extra[6]); | |
9ee44efb PP |
2209 | |
2210 | /* Control never returns here. */ | |
4fbcfc2e PH |
2211 | } |
2212 | ||
9ee44efb | 2213 | /* No need to re-exec; SIGALRM remains set to the default handler */ |
059ec3d9 | 2214 | |
ff966302 JH |
2215 | #ifdef EXPERIMENTAL_QUEUE_RAMP |
2216 | if (*queuerun_msgid) | |
2217 | { | |
6641ba45 | 2218 | log_write(0, LOG_MAIN, "notify triggered queue run"); |
ff966302 JH |
2219 | f.queue_2stage = FALSE; |
2220 | queue_run(queuerun_msgid, queuerun_msgid, FALSE); | |
2221 | } | |
2222 | else | |
2223 | #endif | |
2224 | queue_run(NULL, NULL, FALSE); | |
81022793 | 2225 | exim_underbar_exit(EXIT_SUCCESS); |
059ec3d9 PH |
2226 | } |
2227 | ||
9ee44efb | 2228 | if (pid < 0) |
059ec3d9 | 2229 | { |
9ee44efb PP |
2230 | log_write(0, LOG_MAIN|LOG_PANIC, "daemon: fork of queue-runner " |
2231 | "process failed: %s", strerror(errno)); | |
2232 | log_close_all(); | |
2233 | } | |
2234 | else | |
2235 | { | |
d7978c0f | 2236 | for (int i = 0; i < local_queue_run_max; ++i) |
9ee44efb PP |
2237 | if (queue_pid_slots[i] <= 0) |
2238 | { | |
2239 | queue_pid_slots[i] = pid; | |
2240 | queue_run_count++; | |
2241 | break; | |
2242 | } | |
9ee44efb | 2243 | DEBUG(D_any) debug_printf("%d queue-runner process%s running\n", |
d7978c0f | 2244 | queue_run_count, queue_run_count == 1 ? "" : "es"); |
059ec3d9 | 2245 | } |
059ec3d9 | 2246 | } |
059ec3d9 | 2247 | |
9ee44efb | 2248 | /* Reset the alarm clock */ |
059ec3d9 | 2249 | |
9ee44efb | 2250 | sigalrm_seen = FALSE; |
ff966302 JH |
2251 | #ifdef EXPERIMENTAL_QUEUE_RAMP |
2252 | if (*queuerun_msgid) | |
2253 | *queuerun_msgid = 0; | |
2254 | else | |
2255 | #endif | |
2256 | ALARM(queue_interval); | |
9ee44efb PP |
2257 | } |
2258 | ||
2259 | } /* sigalrm_seen */ | |
059ec3d9 PH |
2260 | |
2261 | ||
2262 | /* Sleep till a connection happens if listening, and handle the connection if | |
2263 | that is why we woke up. The FreeBSD operating system requires the use of | |
2264 | select() before accept() because the latter function is not interrupted by | |
2265 | a signal, and we want to wake up for SIGCHLD and SIGALRM signals. Some other | |
2266 | OS do notice signals in accept() but it does no harm to have the select() | |
2267 | in for all of them - and it won't then be a lurking problem for ports to | |
2268 | new OS. In fact, the later addition of listening on specific interfaces only | |
2269 | requires this way of working anyway. */ | |
2270 | ||
8768d548 | 2271 | if (f.daemon_listen) |
059ec3d9 | 2272 | { |
d7978c0f | 2273 | int lcount, select_errno; |
059ec3d9 PH |
2274 | int max_socket = 0; |
2275 | BOOL select_failed = FALSE; | |
2276 | fd_set select_listen; | |
2277 | ||
2278 | FD_ZERO(&select_listen); | |
ff966302 JH |
2279 | if (daemon_notifier_fd >= 0) |
2280 | FD_SET(daemon_notifier_fd, &select_listen); | |
d7978c0f | 2281 | for (int sk = 0; sk < listen_socket_count; sk++) |
059ec3d9 PH |
2282 | { |
2283 | FD_SET(listen_sockets[sk], &select_listen); | |
2284 | if (listen_sockets[sk] > max_socket) max_socket = listen_sockets[sk]; | |
2285 | } | |
2286 | ||
2287 | DEBUG(D_any) debug_printf("Listening...\n"); | |
8e669ac1 PH |
2288 | |
2289 | /* In rare cases we may have had a SIGCHLD signal in the time between | |
2290 | setting the handler (below) and getting back here. If so, pretend that the | |
7d468ab8 | 2291 | select() was interrupted so that we reap the child. This might still leave |
8e669ac1 | 2292 | a small window when a SIGCHLD could get lost. However, since we use SIGCHLD |
7d468ab8 PH |
2293 | only to do the reaping more quickly, it shouldn't result in anything other |
2294 | than a delay until something else causes a wake-up. */ | |
2295 | ||
2296 | if (sigchld_seen) | |
2297 | { | |
2298 | lcount = -1; | |
8e669ac1 | 2299 | errno = EINTR; |
7d468ab8 PH |
2300 | } |
2301 | else | |
7d468ab8 PH |
2302 | lcount = select(max_socket + 1, (SELECT_ARG2_TYPE *)&select_listen, |
2303 | NULL, NULL, NULL); | |
059ec3d9 | 2304 | |
7d468ab8 | 2305 | if (lcount < 0) |
059ec3d9 PH |
2306 | { |
2307 | select_failed = TRUE; | |
2308 | lcount = 1; | |
2309 | } | |
8e669ac1 PH |
2310 | |
2311 | /* Clean up any subprocesses that may have terminated. We need to do this | |
2312 | here so that smtp_accept_max_per_host works when a connection to that host | |
2313 | has completed, and we are about to accept a new one. When this code was | |
2314 | later in the sequence, a new connection could be rejected, even though an | |
2315 | old one had just finished. Preserve the errno from any select() failure for | |
bb6e88ff | 2316 | the use of the common select/accept error processing below. */ |
8e669ac1 | 2317 | |
bb6e88ff PH |
2318 | select_errno = errno; |
2319 | handle_ending_processes(); | |
8e669ac1 PH |
2320 | errno = select_errno; |
2321 | ||
01603eec | 2322 | #ifndef DISABLE_TLS |
b10c87b3 JH |
2323 | /* Create or rotate any required keys */ |
2324 | tls_daemon_init(); | |
2325 | #endif | |
2326 | ||
059ec3d9 | 2327 | /* Loop for all the sockets that are currently ready to go. If select |
7d468ab8 PH |
2328 | actually failed, we have set the count to 1 and select_failed=TRUE, so as |
2329 | to use the common error code for select/accept below. */ | |
059ec3d9 PH |
2330 | |
2331 | while (lcount-- > 0) | |
2332 | { | |
2333 | int accept_socket = -1; | |
6851a9c5 | 2334 | |
059ec3d9 | 2335 | if (!select_failed) |
ff966302 | 2336 | { |
ff966302 JH |
2337 | if ( daemon_notifier_fd >= 0 |
2338 | && FD_ISSET(daemon_notifier_fd, &select_listen)) | |
2339 | { | |
2340 | FD_CLR(daemon_notifier_fd, &select_listen); | |
2341 | sigalrm_seen = daemon_notification(); | |
2342 | break; /* to top of daemon loop */ | |
2343 | } | |
d7978c0f | 2344 | for (int sk = 0; sk < listen_socket_count; sk++) |
059ec3d9 PH |
2345 | if (FD_ISSET(listen_sockets[sk], &select_listen)) |
2346 | { | |
cf73943b | 2347 | len = sizeof(accepted); |
059ec3d9 PH |
2348 | accept_socket = accept(listen_sockets[sk], |
2349 | (struct sockaddr *)&accepted, &len); | |
2350 | FD_CLR(listen_sockets[sk], &select_listen); | |
2351 | break; | |
2352 | } | |
ff966302 | 2353 | } |
059ec3d9 PH |
2354 | |
2355 | /* If select or accept has failed and this was not caused by an | |
2356 | interruption, log the incident and try again. With asymmetric TCP/IP | |
2357 | routing errors such as "No route to network" have been seen here. Also | |
2358 | "connection reset by peer" has been seen. These cannot be classed as | |
2359 | disastrous errors, but they could fill up a lot of log. The code in smail | |
2360 | crashes the daemon after 10 successive failures of accept, on the grounds | |
2361 | that some OS fail continuously. Exim originally followed suit, but this | |
2362 | appears to have caused problems. Now it just keeps going, but instead of | |
2363 | logging each error, it batches them up when they are continuous. */ | |
2364 | ||
2365 | if (accept_socket < 0 && errno != EINTR) | |
2366 | { | |
2367 | if (accept_retry_count == 0) | |
2368 | { | |
2369 | accept_retry_errno = errno; | |
2370 | accept_retry_select_failed = select_failed; | |
2371 | } | |
2372 | else | |
2373 | { | |
2374 | if (errno != accept_retry_errno || | |
2375 | select_failed != accept_retry_select_failed || | |
2376 | accept_retry_count >= 50) | |
2377 | { | |
2378 | log_write(0, LOG_MAIN | ((accept_retry_count >= 50)? LOG_PANIC : 0), | |
2379 | "%d %s() failure%s: %s", | |
2380 | accept_retry_count, | |
2381 | accept_retry_select_failed? "select" : "accept", | |
2382 | (accept_retry_count == 1)? "" : "s", | |
2383 | strerror(accept_retry_errno)); | |
2384 | log_close_all(); | |
2385 | accept_retry_count = 0; | |
2386 | accept_retry_errno = errno; | |
2387 | accept_retry_select_failed = select_failed; | |
2388 | } | |
2389 | } | |
2390 | accept_retry_count++; | |
2391 | } | |
2392 | ||
2393 | else | |
2394 | { | |
2395 | if (accept_retry_count > 0) | |
2396 | { | |
2397 | log_write(0, LOG_MAIN, "%d %s() failure%s: %s", | |
2398 | accept_retry_count, | |
2399 | accept_retry_select_failed? "select" : "accept", | |
2400 | (accept_retry_count == 1)? "" : "s", | |
2401 | strerror(accept_retry_errno)); | |
2402 | log_close_all(); | |
2403 | accept_retry_count = 0; | |
2404 | } | |
2405 | } | |
2406 | ||
2407 | /* If select/accept succeeded, deal with the connection. */ | |
2408 | ||
2409 | if (accept_socket >= 0) | |
9ee44efb PP |
2410 | { |
2411 | if (inetd_wait_timeout) | |
2412 | last_connection_time = time(NULL); | |
059ec3d9 PH |
2413 | handle_smtp_call(listen_sockets, listen_socket_count, accept_socket, |
2414 | (struct sockaddr *)&accepted); | |
9ee44efb | 2415 | } |
059ec3d9 PH |
2416 | } |
2417 | } | |
2418 | ||
2419 | /* If not listening, then just sleep for the queue interval. If we woke | |
2420 | up early the last time for some other signal, it won't matter because | |
2421 | the alarm signal will wake at the right time. This code originally used | |
2422 | sleep() but it turns out that on the FreeBSD system, sleep() is not inter- | |
2423 | rupted by signals, so it wasn't waking up for SIGALRM or SIGCHLD. Luckily | |
2424 | select() can be used as an interruptible sleep() on all versions of Unix. */ | |
2425 | ||
2426 | else | |
2427 | { | |
2428 | struct timeval tv; | |
2429 | tv.tv_sec = queue_interval; | |
2430 | tv.tv_usec = 0; | |
2431 | select(0, NULL, NULL, NULL, &tv); | |
8e669ac1 | 2432 | handle_ending_processes(); |
059ec3d9 PH |
2433 | } |
2434 | ||
2435 | /* Re-enable the SIGCHLD handler if it has been run. It can't do it | |
2436 | for itself, because it isn't doing the waiting itself. */ | |
2437 | ||
2438 | if (sigchld_seen) | |
2439 | { | |
2440 | sigchld_seen = FALSE; | |
7d468ab8 | 2441 | os_non_restarting_signal(SIGCHLD, main_sigchld_handler); |
059ec3d9 PH |
2442 | } |
2443 | ||
2444 | /* Handle being woken by SIGHUP. We know at this point that the result | |
2445 | of accept() has been dealt with, so we can re-exec exim safely, first | |
2446 | closing the listening sockets so that they can be reused. Cancel any pending | |
2447 | alarm in case it is just about to go off, and set SIGHUP to be ignored so | |
2448 | that another HUP in quick succession doesn't clobber the new daemon before it | |
2449 | gets going. All log files get closed by the close-on-exec flag; however, if | |
2450 | the exec fails, we need to close the logs. */ | |
2451 | ||
2452 | if (sighup_seen) | |
2453 | { | |
059ec3d9 PH |
2454 | log_write(0, LOG_MAIN, "pid %d: SIGHUP received: re-exec daemon", |
2455 | getpid()); | |
8cfc4d82 JH |
2456 | close_daemon_sockets(daemon_notifier_fd, |
2457 | listen_sockets, listen_socket_count); | |
c2a1bba0 | 2458 | ALARM_CLR(0); |
059ec3d9 PH |
2459 | signal(SIGHUP, SIG_IGN); |
2460 | sighup_argv[0] = exim_path; | |
2461 | exim_nullstd(); | |
2462 | execv(CS exim_path, (char *const *)sighup_argv); | |
2463 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "pid %d: exec of %s failed: %s", | |
2464 | getpid(), exim_path, strerror(errno)); | |
2465 | log_close_all(); | |
2466 | } | |
2467 | ||
2468 | } /* End of main loop */ | |
2469 | ||
2470 | /* Control never reaches here */ | |
2471 | } | |
2472 | ||
071c51f7 JH |
2473 | /* vi: aw ai sw=2 |
2474 | */ | |
059ec3d9 | 2475 | /* End of exim_daemon.c */ |