-/* $Cambridge: exim/src/src/daemon.c,v 1.18 2006/11/07 15:56:17 ph10 Exp $ */
-
/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2006 */
+/* Copyright (c) University of Cambridge 1995 - 2009 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions concerned with running Exim as a daemon */
* Local static variables *
*************************************************/
-static volatile BOOL sigchld_seen;
-static volatile BOOL sighup_seen;
+static SIGNAL_BOOL sigchld_seen;
+static SIGNAL_BOOL sighup_seen;
static int accept_retry_count = 0;
static int accept_retry_errno;
if (smtp_load_reserve >= 0)
{
- load_average = os_getloadavg();
+ load_average = OS_GETLOADAVG();
if (smtp_reserve_hosts == NULL && load_average > smtp_load_reserve)
{
DEBUG(D_any) debug_printf("rejecting SMTP connection: load average = %.2f\n",
int old_pool = store_pool;
int save_debug_selector = debug_selector;
BOOL local_queue_only;
+ BOOL session_local_queue_only;
#ifdef SA_NOCLDWAIT
struct sigaction act;
#endif
+ smtp_accept_count++; /* So that it includes this process */
+
/* May have been modified for the subprocess */
log_write_selector = use_log_write_selector;
/* Initialize the queueing flags */
queue_check_only();
- local_queue_only = queue_only;
+ session_local_queue_only = queue_only;
/* Close the listening sockets, and set the SIGCHLD handler to SIG_IGN.
We also attempt to set things up so that children are automatically reaped,
for (i = 0; i < listen_socket_count; i++) (void)close(listen_sockets[i]);
+ /* Set FD_CLOEXEC on the SMTP socket. We don't want any rogue child processes
+ to be able to communicate with them, under any circumstances. */
+ (void)fcntl(accept_socket, F_SETFD,
+ fcntl(accept_socket, F_GETFD) | FD_CLOEXEC);
+ (void)fcntl(dup_accept_socket, F_SETFD,
+ fcntl(dup_accept_socket, F_GETFD) | FD_CLOEXEC);
+
#ifdef SA_NOCLDWAIT
act.sa_handler = SIG_IGN;
sigemptyset(&(act.sa_mask));
if (debug_daemon) debug_selector = 0;
/* If there are too many child processes for immediate delivery,
- set the local_queue_only flag, which is initialized from the
+ set the session_local_queue_only flag, which is initialized from the
configured value and may therefore already be TRUE. Leave logging
- till later so it will have a message id attached. */
+ till later so it will have a message id attached. Note that there is no
+ possibility of re-calculating this per-message, because the value of
+ smtp_accept_count does not change in this subprocess. */
- if (smtp_accept_queue > 0 && smtp_accept_count >= smtp_accept_queue)
+ if (smtp_accept_queue > 0 && smtp_accept_count > smtp_accept_queue)
{
- local_queue_only = TRUE;
+ session_local_queue_only = TRUE;
queue_only_reason = 1;
}
/* Handle the start of the SMTP session, then loop, accepting incoming
messages from the SMTP connection. The end will come at the QUIT command,
when smtp_setup_msg() returns 0. A break in the connection causes the
- process to die (see accept.c). */
+ process to die (see accept.c).
+
+ NOTE: We do *not* call smtp_log_no_mail() if smtp_start_session() fails,
+ because a log line has already been written for all its failure exists
+ (usually "connection refused: <reason>") and writing another one is
+ unnecessary clutter. */
if (!smtp_start_session())
{
if (!ok) /* Connection was dropped */
{
mac_smtp_fflush();
+ smtp_log_no_mail(); /* Log no mail if configured */
_exit(EXIT_SUCCESS);
}
if (message_id[0] == 0) continue; /* No message was accepted */
{
mac_smtp_fflush();
search_tidyup();
+ smtp_log_no_mail(); /* Log no mail if configured */
_exit((rc == 0)? EXIT_SUCCESS : EXIT_FAILURE);
}
store_reset(reset_point);
/* If queue_only is set or if there are too many incoming connections in
- existence, local_queue_only will be TRUE. If it is not, check whether we
- have received too many messages in this session for immediate delivery. If
- not, and queue_only_load is set, check that the load average is below it.
- Note that, once set, local_queue_only remains set for any subsequent
- messages on the same SMTP connection. This is a deliberate choice; even
- though the load average may fall, it doesn't seem right to deliver later
- messages on the same call when not delivering earlier ones. */
-
- if (!local_queue_only)
+ existence, session_local_queue_only will be TRUE. If it is not, check
+ whether we have received too many messages in this session for immediate
+ delivery. */
+
+ if (!session_local_queue_only &&
+ smtp_accept_queue_per_connection > 0 &&
+ receive_messagecount > smtp_accept_queue_per_connection)
{
- if (smtp_accept_queue_per_connection > 0 &&
- receive_messagecount > smtp_accept_queue_per_connection)
- {
- local_queue_only = TRUE;
- queue_only_reason = 2;
- }
- else if (queue_only_load >= 0)
+ session_local_queue_only = TRUE;
+ queue_only_reason = 2;
+ }
+
+ /* Initialize local_queue_only from session_local_queue_only. If it is not
+ true, and queue_only_load is set, check that the load average is below it.
+ If local_queue_only is set by this means, we also set if for the session if
+ queue_only_load_latch is true (the default). This means that, once set,
+ local_queue_only remains set for any subsequent messages on the same SMTP
+ connection. This is a deliberate choice; even though the load average may
+ fall, it doesn't seem right to deliver later messages on the same call when
+ not delivering earlier ones. However, the are special circumstances such as
+ very long-lived connections from scanning appliances where this is not the
+ best strategy. In such cases, queue_only_load_latch should be set false. */
+
+ local_queue_only = session_local_queue_only;
+ if (!local_queue_only && queue_only_load >= 0)
+ {
+ local_queue_only = (load_average = OS_GETLOADAVG()) > queue_only_load;
+ if (local_queue_only)
{
- local_queue_only = (load_average = os_getloadavg()) > queue_only_load;
- if (local_queue_only) queue_only_reason = 3;
+ queue_only_reason = 3;
+ if (queue_only_load_latch) session_local_queue_only = TRUE;
}
}
while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
{
int i;
- DEBUG(D_any) debug_printf("child %d ended: status=0x%x\n", (int)pid,
- status);
+ DEBUG(D_any)
+ {
+ debug_printf("child %d ended: status=0x%x\n", (int)pid, status);
+#ifdef WCOREDUMP
+ if (WIFEXITED(status))
+ debug_printf(" normal exit, %d\n", WEXITSTATUS(status));
+ else if (WIFSIGNALED(status))
+ debug_printf(" signal exit, signal %d%s\n", WTERMSIG(status),
+ WCOREDUMP(status) ? " (core dumped)" : "");
+#endif
+ }
/* If it's a listening daemon for which we are keeping track of individual
subprocesses, deal with an accepting process that has terminated. */
void
daemon_go(void)
{
+struct passwd *pw;
int *listen_sockets = NULL;
int listen_socket_count = 0;
ip_address_item *addresses = NULL;
+time_t last_connection_time = (time_t)0;
/* If any debugging options are set, turn on the D_pid bit so that all
debugging lines get the pid added. */
DEBUG(D_any|D_v) debug_selector |= D_pid;
+if (inetd_wait_mode)
+ {
+ int on = 1;
+
+ listen_socket_count = 1;
+ listen_sockets = store_get(sizeof(int *));
+ (void) close(3);
+ if (dup2(0, 3) == -1)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE,
+ "failed to dup inetd socket safely away: %s", strerror(errno));
+ }
+ listen_sockets[0] = 3;
+ (void) close(0);
+ (void) close(1);
+ (void) close(2);
+ exim_nullstd();
+
+ if (debug_file == stderr)
+ {
+ /* need a call to log_write before call to open debug_file, so that
+ log.c:file_path has been initialised. This is unfortunate. */
+ log_write(0, LOG_MAIN, "debugging Exim in inetd wait mode starting");
+
+ fclose(debug_file);
+ debug_file = NULL;
+ exim_nullstd(); /* re-open fd2 after we just closed it again */
+ debug_logging_activate(US"-wait", NULL);
+ }
+
+ DEBUG(D_any) debug_printf("running in inetd wait mode\n");
+
+ /* As per below, when creating sockets ourselves, we handle tcp_nodelay for
+ our own buffering; we assume though that inetd set the socket REUSEADDR. */
+
+ if (tcp_nodelay) setsockopt(3, IPPROTO_TCP, TCP_NODELAY,
+ (uschar *)(&on), sizeof(on));
+ }
+
+
+if (inetd_wait_mode || daemon_listen)
+ {
+ /* If any option requiring a load average to be available during the
+ reception of a message is set, call os_getloadavg() while we are root
+ for those OS for which this is necessary the first time it is called (in
+ order to perform an "open" on the kernel memory file). */
+
+ #ifdef LOAD_AVG_NEEDS_ROOT
+ if (queue_only_load >= 0 || smtp_load_reserve >= 0 ||
+ (deliver_queue_load_max >= 0 && deliver_drop_privilege))
+ (void)os_getloadavg();
+ #endif
+ }
+
/* Do the preparation for setting up a listener on one or more interfaces, and
possible on various ports. This is controlled by the combination of
first, so that we can return non-zero if there are any syntax errors, and also
write to stderr. */
-if (daemon_listen)
+if (daemon_listen && !inetd_wait_mode)
{
int *default_smtp_port;
int sep;
ip_address_item *ipa;
ip_address_item **pipa;
- /* If any option requiring a load average to be available during the
- reception of a message is set, call os_getloadavg() while we are root
- for those OS for which this is necessary the first time it is called (in
- order to perform an "open" on the kernel memory file). */
-
- #ifdef LOAD_AVG_NEEDS_ROOT
- if (queue_only_load >= 0 || smtp_load_reserve >= 0 ||
- (deliver_queue_load_max >= 0 && deliver_drop_privilege))
- (void)os_getloadavg();
- #endif
-
/* If -oX was used, disable the writing of a pid file unless -oP was
explicitly used to force it. Then scan the string given to -oX. Any items
that contain neither a dot nor a colon are used to override daemon_smtp_port.
listen_socket_count++;
listen_sockets = store_get(sizeof(int *) * listen_socket_count);
+ } /* daemon_listen but not inetd_wait_mode */
+
+if (daemon_listen)
+ {
+
/* Do a sanity check on the max connects value just to save us from getting
a huge amount of store. */
/* The variable background_daemon is always false when debugging, but
can also be forced false in order to keep a non-debugging daemon in the
foreground. If background_daemon is true, close all open file descriptors that
-we know about, but then re-open stdin, stdout, and stderr to /dev/null.
+we know about, but then re-open stdin, stdout, and stderr to /dev/null. Also
+do this for inetd_wait mode.
This is protection against any called functions (in libraries, or in
Perl, or whatever) that think they can write to stderr (or stdout). Before this
setsid() for getting rid of the controlling terminal. For any OS that doesn't,
setsid() can be #defined as a no-op, or as something else. */
-if (background_daemon)
+if (background_daemon || inetd_wait_mode)
{
log_close_all(); /* Just in case anything was logged earlier */
search_tidyup(); /* Just in case any were used in reading the config. */
(void)close(2);
exim_nullstd(); /* Connect stdin/stdout/stderr to /dev/null */
log_stderr = NULL; /* So no attempt to copy paniclog output */
+ }
+if (background_daemon)
+ {
/* If the parent process of this one has pid == 1, we are re-initializing the
daemon as the result of a SIGHUP. In this case, there is no need to do
anything, because the controlling terminal has long gone. Otherwise, fork, in
/* We are now in the disconnected, daemon process (unless debugging). Set up
the listening sockets if required. */
-if (daemon_listen)
+if (daemon_listen && !inetd_wait_mode)
{
int sk;
int on = 1;
exim_setugid(exim_uid, exim_gid, geteuid()==root_uid, US"running as a daemon");
+/* Update the originator_xxx fields so that received messages as listed as
+coming from Exim, not whoever started the daemon. */
+
+originator_uid = exim_uid;
+originator_gid = exim_gid;
+originator_login = ((pw = getpwuid(exim_uid)) != NULL)?
+ string_copy_malloc(US pw->pw_name) : US"exim";
+
/* Get somewhere to keep the list of queue-runner pids if we are keeping track
of them (and also if we are doing queue runs). */
/* Log the start up of a daemon - at least one of listening or queue running
must be set up. */
-if (daemon_listen)
+if (inetd_wait_mode)
+ {
+ uschar *p = big_buffer;
+
+ if (inetd_wait_timeout >= 0)
+ sprintf(CS p, "terminating after %d seconds", inetd_wait_timeout);
+ else
+ sprintf(CS p, "with no wait timeout");
+
+ log_write(0, LOG_MAIN,
+ "exim %s daemon started: pid=%d, launched with listening socket, %s",
+ version_string, getpid(), big_buffer);
+ set_process_info("daemon: pre-listening socket");
+
+ /* set up the timeout logic */
+ sigalrm_seen = 1;
+ }
+
+else if (daemon_listen)
{
int i, j;
int smtp_ports = 0;
struct sockaddr_in accepted;
#endif
- EXIM_SOCKLEN_T len = sizeof(accepted);
+ EXIM_SOCKLEN_T len;
pid_t pid;
/* This code is placed first in the loop, so that it gets obeyed at the
- start, before the first wait. This causes the first queue-runner to be
- started immediately. */
+ start, before the first wait, for the queue-runner case, so that the first
+ one can be started immediately.
+
+ The other option is that we have an inetd wait timeout specified to -bw. */
if (sigalrm_seen)
{
- DEBUG(D_any) debug_printf("SIGALRM received\n");
+ if (inetd_wait_timeout > 0)
+ {
+ time_t resignal_interval = inetd_wait_timeout;
+
+ if (last_connection_time == (time_t)0)
+ {
+ DEBUG(D_any)
+ debug_printf("inetd wait timeout expired, but still not seen first message, ignoring\n");
+ }
+ else
+ {
+ time_t now = time(NULL);
+ if (now == (time_t)-1)
+ {
+ DEBUG(D_any) debug_printf("failed to get time: %s\n", strerror(errno));
+ }
+ else
+ {
+ if ((now - last_connection_time) >= inetd_wait_timeout)
+ {
+ DEBUG(D_any)
+ debug_printf("inetd wait timeout %d expired, ending daemon\n",
+ inetd_wait_timeout);
+ log_write(0, LOG_MAIN, "exim %s daemon terminating, inetd wait timeout reached.\n",
+ version_string);
+ exit(EXIT_SUCCESS);
+ }
+ else
+ {
+ resignal_interval -= (now - last_connection_time);
+ }
+ }
+ }
- /* Do a full queue run in a child process, if required, unless we already
- have enough queue runners on the go. If we are not running as root, a
- re-exec is required. */
+ sigalrm_seen = FALSE;
+ alarm(resignal_interval);
+ }
- if (queue_interval > 0 &&
- (queue_run_max <= 0 || queue_run_count < queue_run_max))
+ else
{
- if ((pid = fork()) == 0)
- {
- int sk;
+ DEBUG(D_any) debug_printf("SIGALRM received\n");
- DEBUG(D_any) debug_printf("Starting queue-runner: pid %d\n",
- (int)getpid());
+ /* Do a full queue run in a child process, if required, unless we already
+ have enough queue runners on the go. If we are not running as root, a
+ re-exec is required. */
- /* Disable debugging if it's required only for the daemon process. We
- leave the above message, because it ties up with the "child ended"
- debugging messages. */
+ if (queue_interval > 0 &&
+ (queue_run_max <= 0 || queue_run_count < queue_run_max))
+ {
+ if ((pid = fork()) == 0)
+ {
+ int sk;
- if (debug_daemon) debug_selector = 0;
+ DEBUG(D_any) debug_printf("Starting queue-runner: pid %d\n",
+ (int)getpid());
- /* Close any open listening sockets in the child */
+ /* Disable debugging if it's required only for the daemon process. We
+ leave the above message, because it ties up with the "child ended"
+ debugging messages. */
- for (sk = 0; sk < listen_socket_count; sk++)
- (void)close(listen_sockets[sk]);
+ if (debug_daemon) debug_selector = 0;
- /* Reset SIGHUP and SIGCHLD in the child in both cases. */
+ /* Close any open listening sockets in the child */
- signal(SIGHUP, SIG_DFL);
- signal(SIGCHLD, SIG_DFL);
+ for (sk = 0; sk < listen_socket_count; sk++)
+ (void)close(listen_sockets[sk]);
- /* Re-exec if privilege has been given up, unless deliver_drop_
- privilege is set. Reset SIGALRM before exec(). */
+ /* Reset SIGHUP and SIGCHLD in the child in both cases. */
- if (geteuid() != root_uid && !deliver_drop_privilege)
- {
- uschar opt[8];
- uschar *p = opt;
- uschar *extra[4];
- int extracount = 1;
+ signal(SIGHUP, SIG_DFL);
+ signal(SIGCHLD, SIG_DFL);
- signal(SIGALRM, SIG_DFL);
- *p++ = '-';
- *p++ = 'q';
- if (queue_2stage) *p++ = 'q';
- if (queue_run_first_delivery) *p++ = 'i';
- if (queue_run_force) *p++ = 'f';
- if (deliver_force_thaw) *p++ = 'f';
- if (queue_run_local) *p++ = 'l';
- *p = 0;
- extra[0] = opt;
-
- /* If -R or -S were on the original command line, ensure they get
- passed on. */
-
- if (deliver_selectstring != NULL)
- {
- extra[extracount++] = deliver_selectstring_regex? US"-Rr" : US"-R";
- extra[extracount++] = deliver_selectstring;
- }
+ /* Re-exec if privilege has been given up, unless deliver_drop_
+ privilege is set. Reset SIGALRM before exec(). */
- if (deliver_selectstring_sender != NULL)
+ if (geteuid() != root_uid && !deliver_drop_privilege)
{
- extra[extracount++] = deliver_selectstring_sender_regex?
- US"-Sr" : US"-S";
- extra[extracount++] = deliver_selectstring_sender;
+ uschar opt[8];
+ uschar *p = opt;
+ uschar *extra[5];
+ int extracount = 1;
+
+ signal(SIGALRM, SIG_DFL);
+ *p++ = '-';
+ *p++ = 'q';
+ if (queue_2stage) *p++ = 'q';
+ if (queue_run_first_delivery) *p++ = 'i';
+ if (queue_run_force) *p++ = 'f';
+ if (deliver_force_thaw) *p++ = 'f';
+ if (queue_run_local) *p++ = 'l';
+ *p = 0;
+ extra[0] = opt;
+
+ /* If -R or -S were on the original command line, ensure they get
+ passed on. */
+
+ if (deliver_selectstring != NULL)
+ {
+ extra[extracount++] = deliver_selectstring_regex? US"-Rr" : US"-R";
+ extra[extracount++] = deliver_selectstring;
+ }
+
+ if (deliver_selectstring_sender != NULL)
+ {
+ extra[extracount++] = deliver_selectstring_sender_regex?
+ US"-Sr" : US"-S";
+ extra[extracount++] = deliver_selectstring_sender;
+ }
+
+ /* Overlay this process with a new execution. */
+
+ (void)child_exec_exim(CEE_EXEC_PANIC, FALSE, NULL, TRUE, extracount,
+ extra[0], extra[1], extra[2], extra[3], extra[4]);
+
+ /* Control never returns here. */
}
- /* Overlay this process with a new execution. */
-
- (void)child_exec_exim(CEE_EXEC_PANIC, FALSE, NULL, TRUE, extracount,
- extra[0], extra[1], extra[2], extra[3], extra[4]);
+ /* No need to re-exec; SIGALRM remains set to the default handler */
- /* Control never returns here. */
+ queue_run(NULL, NULL, FALSE);
+ _exit(EXIT_SUCCESS);
}
- /* No need to re-exec; SIGALRM remains set to the default handler */
-
- queue_run(NULL, NULL, FALSE);
- _exit(EXIT_SUCCESS);
- }
-
- if (pid < 0)
- {
- log_write(0, LOG_MAIN|LOG_PANIC, "daemon: fork of queue-runner "
- "process failed: %s", strerror(errno));
- log_close_all();
- }
- else
- {
- int i;
- for (i = 0; i < queue_run_max; ++i)
+ if (pid < 0)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "daemon: fork of queue-runner "
+ "process failed: %s", strerror(errno));
+ log_close_all();
+ }
+ else
{
- if (queue_pid_slots[i] <= 0)
+ int i;
+ for (i = 0; i < queue_run_max; ++i)
{
- queue_pid_slots[i] = pid;
- queue_run_count++;
- break;
+ if (queue_pid_slots[i] <= 0)
+ {
+ queue_pid_slots[i] = pid;
+ queue_run_count++;
+ break;
+ }
}
+ DEBUG(D_any) debug_printf("%d queue-runner process%s running\n",
+ queue_run_count, (queue_run_count == 1)? "" : "es");
}
- DEBUG(D_any) debug_printf("%d queue-runner process%s running\n",
- queue_run_count, (queue_run_count == 1)? "" : "es");
}
- }
- /* Reset the alarm clock */
+ /* Reset the alarm clock */
- sigalrm_seen = FALSE;
- alarm(queue_interval);
- }
+ sigalrm_seen = FALSE;
+ alarm(queue_interval);
+ }
+
+ } /* sigalrm_seen */
/* Sleep till a connection happens if listening, and handle the connection if
{
if (FD_ISSET(listen_sockets[sk], &select_listen))
{
+ len = sizeof(accepted);
accept_socket = accept(listen_sockets[sk],
(struct sockaddr *)&accepted, &len);
FD_CLR(listen_sockets[sk], &select_listen);
/* If select/accept succeeded, deal with the connection. */
if (accept_socket >= 0)
+ {
+ if (inetd_wait_timeout)
+ last_connection_time = time(NULL);
handle_smtp_call(listen_sockets, listen_socket_count, accept_socket,
(struct sockaddr *)&accepted);
+ }
}
}
projects / exim.git / blobdiff