X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/ca261bddd08ddf2091b9ef84a6a02ff232c25aa5..a85c067ba6c6940512cf57ec213277a370d87e70:/src/src/daemon.c diff --git a/src/src/daemon.c b/src/src/daemon.c index 548daf0ac..0afc7ca86 100644 --- a/src/src/daemon.c +++ b/src/src/daemon.c @@ -2,9 +2,10 @@ * Exim - an Internet mail transport agent * *************************************************/ +/* Copyright (c) The Exim Maintainers 2020 - 2022 */ /* Copyright (c) University of Cambridge 1995 - 2018 */ -/* Copyright (c) The Exim Maintainers 2020 */ /* See the file NOTICE for conditions of use and distribution. */ +/* SPDX-License-Identifier: GPL-2.0-only */ /* Functions concerned with running Exim as a daemon */ @@ -87,7 +88,7 @@ sigchld_seen = TRUE; } -/* SIGTERM handler. Try to get the damon pif file removed +/* SIGTERM handler. Try to get the daemon pid file removed before exiting. */ static void @@ -141,7 +142,7 @@ Uunlink(s); static void close_daemon_sockets(int daemon_notifier_fd, - int * listen_sockets, int listen_socket_count) + struct pollfd * fd_polls, int listen_socket_count) { if (daemon_notifier_fd >= 0) { @@ -152,7 +153,7 @@ if (daemon_notifier_fd >= 0) #endif } -for (int i = 0; i < listen_socket_count; i++) (void) close(listen_sockets[i]); +for (int i = 0; i < listen_socket_count; i++) (void) close(fd_polls[i].fd); } @@ -167,7 +168,7 @@ is required so that they can be closed in the sub-process. Take care not to leak store in this process - reset the stacking pool at the end. Arguments: - listen_sockets sockets which are listening for incoming calls + fd_polls sockets which are listening for incoming calls listen_socket_count count of listening sockets accept_socket socket of the current accepted call accepted socket information about the current call @@ -176,7 +177,7 @@ Returns: nothing */ static void -handle_smtp_call(int *listen_sockets, int listen_socket_count, +handle_smtp_call(struct pollfd *fd_polls, int listen_socket_count, int accept_socket, struct sockaddr *accepted) { pid_t pid; @@ -459,7 +460,7 @@ if (pid == 0) extensive comment before the reception loop in exim.c for a fuller explanation of this logic. */ - close_daemon_sockets(daemon_notifier_fd, listen_sockets, listen_socket_count); + close_daemon_sockets(daemon_notifier_fd, fd_polls, listen_socket_count); /* 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. */ @@ -793,10 +794,8 @@ else (void)close(dup_accept_socket); the incoming host address and an expanded active_hostname. */ log_close_all(); -interface_address = -sender_host_address = NULL; +interface_address = sender_host_name = sender_host_address = NULL; store_reset(reset_point); -sender_host_address = NULL; } @@ -1134,13 +1133,43 @@ exim_exit(EXIT_SUCCESS); * Listener socket for local work prompts * *************************************************/ +ssize_t +daemon_client_sockname(struct sockaddr_un * sup, uschar ** sname) +{ +#ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS +sup->sun_path[0] = 0; /* Abstract local socket addr - Linux-specific? */ +return offsetof(struct sockaddr_un, sun_path) + 1 + + snprintf(sup->sun_path+1, sizeof(sup->sun_path)-1, "exim_%d", getpid()); +#else +*sname = string_sprintf("%s/p_%d", spool_directory, getpid()); +return offsetof(struct sockaddr_un, sun_path) + + snprintf(sup->sun_path, sizeof(sup->sun_path), "%s", sname); +#endif +} + +ssize_t +daemon_notifier_sockname(struct sockaddr_un * sup) +{ +#ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS +sup->sun_path[0] = 0; /* Abstract local socket addr - Linux-specific? */ +return offsetof(struct sockaddr_un, sun_path) + 1 + + snprintf(sup->sun_path+1, sizeof(sup->sun_path)-1, "%s", + expand_string(notifier_socket)); +#else +return offsetof(struct sockaddr_un, sun_path) + + snprintf(sup->sun_path, sizeof(sup->sun_path), "%s", + expand_string(notifier_socket)); +#endif +} + + static void daemon_notifier_socket(void) { int fd; const uschar * where; struct sockaddr_un sa_un = {.sun_family = AF_UNIX}; -int len; +ssize_t len; if (!notifier_socket || !*notifier_socket) { @@ -1165,20 +1194,15 @@ if ((fd = socket(PF_UNIX, SOCK_DGRAM, 0)) < 0) (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC); #endif +len = daemon_notifier_sockname(&sa_un); + #ifdef EXIM_HAVE_ABSTRACT_UNIX_SOCKETS -sa_un.sun_path[0] = 0; /* Abstract local socket addr - Linux-specific? */ -len = offsetof(struct sockaddr_un, sun_path) + 1 - + snprintf(sa_un.sun_path+1, sizeof(sa_un.sun_path)-1, "%s", - expand_string(notifier_socket)); DEBUG(D_any) debug_printf(" @%s\n", sa_un.sun_path+1); #else /* filesystem-visible and persistent; will neeed removal */ -len = offsetof(struct sockaddr_un, sun_path) - + snprintf(sa_un.sun_path, sizeof(sa_un.sun_path), "%s", - expand_string(notifier_socket)); DEBUG(D_any) debug_printf(" %s\n", sa_un.sun_path); #endif -if (bind(fd, (const struct sockaddr *)&sa_un, len) < 0) +if (bind(fd, (const struct sockaddr *)&sa_un, (socklen_t)len) < 0) { where = US"bind"; goto bad; } #ifdef SO_PASSCRED /* Linux */ @@ -1207,7 +1231,11 @@ bad: static uschar queuerun_msgid[MESSAGE_ID_LENGTH+1]; -/* Return TRUE if a sigalrm should be emulated */ +/* The notifier socket has something to read. Pull the message from it, decode +and do the action. + +Return TRUE if a sigalrm should be emulated */ + static BOOL daemon_notification(void) { @@ -1257,7 +1285,6 @@ for (struct cmsghdr * cp = CMSG_FIRSTHDR(&msg); { DEBUG(D_queue_run) debug_printf("%s: sender creds pid %d uid %d gid %d\n", __FUNCTION__, (int)cr->pid, (int)cr->uid, (int)cr->gid); - return FALSE; } # elif defined(LOCAL_CREDS) /* BSD-ish */ struct sockcred * cr = (struct sockcred *) CMSG_DATA(cp); @@ -1265,7 +1292,6 @@ for (struct cmsghdr * cp = CMSG_FIRSTHDR(&msg); { DEBUG(D_queue_run) debug_printf("%s: sender creds pid ??? uid %d gid %d\n", __FUNCTION__, (int)cr->sc_uid, (int)cr->sc_gid); - return FALSE; } # endif break; @@ -1296,22 +1322,18 @@ switch (buf[0]) (const struct sockaddr *)&sa_un, msg.msg_namelen) < 0) log_write(0, LOG_MAIN|LOG_PANIC, "%s: sendto: %s\n", __FUNCTION__, strerror(errno)); - return FALSE; + break; } + + case NOTIFY_REGEX: + regex_at_daemon(buf); + break; } return FALSE; } - -static void -add_listener_socket(int fd, fd_set * fds, int * fd_max) -{ -FD_SET(fd, fds); -if (fd > *fd_max) *fd_max = fd; -} - /************************************************* * Exim Daemon Mainline * *************************************************/ @@ -1339,9 +1361,8 @@ void daemon_go(void) { struct passwd * pw; -int * listen_sockets = NULL; -int listen_socket_count = 0, listen_fd_max = 0; -fd_set select_listen; +struct pollfd * fd_polls, * tls_watch_poll = NULL, * dnotify_poll = NULL; +int listen_socket_count = 0, poll_fd_count; ip_address_item * addresses = NULL; time_t last_connection_time = (time_t)0; int local_queue_run_max = atoi(CS expand_string(queue_run_max)); @@ -1353,17 +1374,21 @@ debugging lines get the pid added. */ DEBUG(D_any|D_v) debug_selector |= D_pid; -FD_ZERO(&select_listen); +/* Allocate enough pollstructs for inetd mode plus the ancillary sockets; +also used when there are no listen sockets. */ + +fd_polls = store_get(sizeof(struct pollfd) * 3, GET_UNTAINTED); + if (f.inetd_wait_mode) { listen_socket_count = 1; - listen_sockets = store_get(sizeof(int), FALSE); (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; + fd_polls[0].fd = 3; + fd_polls[0].events = POLLIN; (void) close(0); (void) close(1); (void) close(2); @@ -1390,9 +1415,6 @@ if (f.inetd_wait_mode) if (setsockopt(3, IPPROTO_TCP, TCP_NODELAY, US &on, sizeof(on))) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "failed to set socket NODELAY: %s", strerror(errno)); - - FD_SET(3, &select_listen); - listen_fd_max = 3; } @@ -1543,7 +1565,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) sep = 0; while ((s = string_nextinlist(&list, &sep, NULL, 0))) pct++; - default_smtp_port = store_get((pct+1) * sizeof(int), FALSE); + default_smtp_port = store_get((pct+1) * sizeof(int), GET_UNTAINTED); list = daemon_smtp_port; sep = 0; for (pct = 0; @@ -1632,7 +1654,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) ipa->port = default_smtp_port[0]; for (int i = 1; default_smtp_port[i] > 0; i++) { - ip_address_item *new = store_get(sizeof(ip_address_item), FALSE); + ip_address_item * new = store_get(sizeof(ip_address_item), GET_UNTAINTED); memcpy(new->address, ipa->address, Ustrlen(ipa->address) + 1); new->port = default_smtp_port[i]; @@ -1686,11 +1708,16 @@ if (f.daemon_listen && !f.inetd_wait_mode) } } - /* Get a vector to remember all the sockets in */ + /* Get a vector to remember all the sockets in. + Two extra elements for the ancillary sockets */ for (ipa = addresses; ipa; ipa = ipa->next) listen_socket_count++; - listen_sockets = store_get(sizeof(int) * listen_socket_count, FALSE); + fd_polls = store_get(sizeof(struct pollfd) * (listen_socket_count + 2), + GET_UNTAINTED); + for (struct pollfd * p = fd_polls; p < fd_polls + listen_socket_count + 2; + p++) + { p->fd = -1; p->events = POLLIN; } } /* daemon_listen but not inetd_wait_mode */ @@ -1713,7 +1740,7 @@ if (f.daemon_listen) if (smtp_accept_max > 0) { - smtp_slots = store_get(smtp_accept_max * sizeof(smtp_slot), FALSE); + smtp_slots = store_get(smtp_accept_max * sizeof(smtp_slot), GET_UNTAINTED); for (int i = 0; i < smtp_accept_max; i++) smtp_slots[i] = empty_smtp_slot; } } @@ -1750,15 +1777,19 @@ if (f.background_daemon) 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 case current process is a process group leader (see 'man setsid' for an - explanation) before calling setsid(). */ + explanation) before calling setsid(). + All other forks want daemon_listen cleared. Rather than blow a register, jsut + restore it here. */ if (getppid() != 1) { + BOOL daemon_listen = f.daemon_listen; pid_t pid = exim_fork(US"daemon"); if (pid < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "fork() failed when starting daemon: %s", strerror(errno)); if (pid > 0) exit(EXIT_SUCCESS); /* in parent process, just exit */ (void)setsid(); /* release controlling terminal */ + f.daemon_listen = daemon_listen; } } @@ -1795,7 +1826,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) wildcard = ipa->address[0] == 0; } - if ((listen_sockets[sk] = fd = ip_socket(SOCK_STREAM, af)) < 0) + if ((fd_polls[sk].fd = fd = ip_socket(SOCK_STREAM, af)) < 0) { if (check_special_case(0, addresses, ipa, FALSE)) { @@ -1804,7 +1835,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) goto SKIP_SOCKET; } log_write(0, LOG_PANIC_DIE, "IPv%c socket creation failed: %s", - (af == AF_INET6)? '6' : '4', strerror(errno)); + af == AF_INET6 ? '6' : '4', strerror(errno)); } /* If this is an IPv6 wildcard socket, set IPV6_V6ONLY if that option is @@ -1813,8 +1844,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) #ifdef IPV6_V6ONLY if (af == AF_INET6 && wildcard && - setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, CS (&on), - sizeof(on)) < 0) + setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) log_write(0, LOG_MAIN, "Setting IPV6_V6ONLY on daemon's IPv6 wildcard " "socket failed (%s): carrying on without it", strerror(errno)); #endif /* IPV6_V6ONLY */ @@ -1823,16 +1853,14 @@ if (f.daemon_listen && !f.inetd_wait_mode) is being handled. Without this, a connection will prevent reuse of the smtp port for listening. */ - if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, - US (&on), sizeof(on)) < 0) + if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "setting SO_REUSEADDR on socket " "failed when starting daemon: %s", strerror(errno)); /* Set TCP_NODELAY; Exim does its own buffering. There is a switch to disable this because it breaks some broken clients. */ - if (tcp_nodelay) setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, - US (&on), sizeof(on)); + if (tcp_nodelay) setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)); /* Now bind the socket to the required port; if Exim is being restarted it may not always be possible to bind immediately, even with SO_REUSEADDR @@ -1906,8 +1934,7 @@ if (f.daemon_listen && !f.inetd_wait_mode) f.tcp_fastopen_ok = FALSE; } #endif - - add_listener_socket(fd, &select_listen, &listen_fd_max); + fd_polls[sk].fd = fd; continue; } @@ -1973,17 +2000,6 @@ if (f.running_in_test_harness || write_pid) DEBUG(D_any) debug_printf("%s pid file %s: %s\n", (operation == PID_WRITE) ? "write" : "check", pid_file_path, strerror(errno)); } -/* Add ancillary sockets to the set for select */ - -#ifndef DISABLE_TLS -if (tls_watch_fd >= 0) - add_listener_socket(tls_watch_fd, &select_listen, &listen_fd_max); -#endif -if (daemon_notifier_fd >= 0) - add_listener_socket(daemon_notifier_fd, &select_listen, &listen_fd_max); - -listen_fd_max++; - /* Set up the handler for SIGHUP, which causes a restart of the daemon. */ sighup_seen = FALSE; @@ -2010,7 +2026,7 @@ of them (and also if we are doing queue runs). */ if (queue_interval > 0 && local_queue_run_max > 0) { - queue_pid_slots = store_get(local_queue_run_max * sizeof(pid_t), FALSE); + queue_pid_slots = store_get(local_queue_run_max * sizeof(pid_t), GET_UNTAINTED); for (int i = 0; i < local_queue_run_max; i++) queue_pid_slots[i] = 0; } @@ -2111,7 +2127,7 @@ else if (f.daemon_listen) if (*--p == '}') *p = '\0'; /* drop EOL */ while (isdigit(*--p)) ; /* char before port */ - i2->log = *p == ':' /* no list yet? */ + i2->log = *p == ':' /* no list yet? { */ ? string_sprintf("%.*s{%s,%d}", (int)(p - i2->log + 1), i2->log, p+1, ipa->port) : string_sprintf("%s,%d}", i2->log, ipa->port); @@ -2199,6 +2215,24 @@ spf_init(); tls_daemon_init(); #endif +/* Add ancillary sockets to the set for select */ + +poll_fd_count = listen_socket_count; +#ifndef DISABLE_TLS +if (tls_watch_fd >= 0) + { + tls_watch_poll = &fd_polls[poll_fd_count++]; + tls_watch_poll->fd = tls_watch_fd; + tls_watch_poll->events = POLLIN; + } +#endif +if (daemon_notifier_fd >= 0) + { + dnotify_poll = &fd_polls[poll_fd_count++]; + dnotify_poll->fd = daemon_notifier_fd; + dnotify_poll->events = POLLIN; + } + /* Close the log so it can be renamed and moved. In the few cases below where this long-running process writes to the log (always exceptional conditions), it closes the log afterwards, for the same reason. */ @@ -2296,7 +2330,7 @@ for (;;) /* Close any open listening sockets in the child */ close_daemon_sockets(daemon_notifier_fd, - listen_sockets, listen_socket_count); + fd_polls, listen_socket_count); /* Reset SIGHUP and SIGCHLD in the child in both cases. */ @@ -2424,9 +2458,8 @@ for (;;) if (f.daemon_listen) { - int check_lsk = 0, lcount; + int lcount; BOOL select_failed = FALSE; - fd_set fds = select_listen; DEBUG(D_any) debug_printf("Listening...\n"); @@ -2443,8 +2476,7 @@ for (;;) errno = EINTR; } else - lcount = select(listen_fd_max, (SELECT_ARG2_TYPE *)&fds, - NULL, NULL, NULL); + lcount = poll(fd_polls, poll_fd_count, -1); if (lcount < 0) { @@ -2464,8 +2496,15 @@ for (;;) handle_ending_processes(); #ifndef DISABLE_TLS + { + int old_tfd; /* Create or rotate any required keys; handle (delayed) filewatch event */ - tls_daemon_tick(); + + if ((old_tfd = tls_daemon_tick()) >= 0) + for (struct pollfd * p = &fd_polls[listen_socket_count]; + p < fd_polls + poll_fd_count; p++) + if (p->fd == old_tfd) { p->fd = tls_watch_fd ; break; } + } #endif errno = select_errno; } @@ -2486,25 +2525,26 @@ for (;;) if (!select_failed) { #if !defined(DISABLE_TLS) && (defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)) - if (tls_watch_fd >= 0 && FD_ISSET(tls_watch_fd, &fds)) + if (tls_watch_poll && tls_watch_poll->revents & POLLIN) { + tls_watch_poll->revents = 0; tls_watch_trigger_time = time(NULL); /* Set up delayed event */ tls_watch_discard_event(tls_watch_fd); break; /* to top of daemon loop */ } #endif - if (daemon_notifier_fd >= 0 && FD_ISSET(daemon_notifier_fd, &fds)) + if (dnotify_poll && dnotify_poll->revents & POLLIN) { + dnotify_poll->revents = 0; sigalrm_seen = daemon_notification(); break; /* to top of daemon loop */ } - while (check_lsk < listen_socket_count) - { - int lfd = listen_sockets[check_lsk++]; - if (FD_ISSET(lfd, &fds)) + for (struct pollfd * p = fd_polls; p < fd_polls + listen_socket_count; + p++) + if (p->revents & POLLIN) { EXIM_SOCKLEN_T alen = sizeof(accepted); -#if defined(TCP_INFO) +#ifdef TCP_INFO struct tcp_info ti; socklen_t tlen = sizeof(ti); @@ -2512,22 +2552,23 @@ for (;;) smtp_listen_backlog = 0; if ( smtp_backlog_monitor > 0 - && getsockopt(lfd, IPPROTO_TCP, TCP_INFO, &ti, &tlen) == 0) + && getsockopt(p->fd, IPPROTO_TCP, TCP_INFO, &ti, &tlen) == 0) { - DEBUG(D_interface) debug_printf("listen fd %d queue max %u curr %u\n", # ifdef EXIM_HAVE_TCPI_UNACKED - lfd, ti.tcpi_sacked, ti.tcpi_unacked); + DEBUG(D_interface) debug_printf("listen fd %d queue max %u curr %u\n", + p->fd, ti.tcpi_sacked, ti.tcpi_unacked); smtp_listen_backlog = ti.tcpi_unacked; # elif defined(__FreeBSD__) /* This does not work. Investigate kernel sourcecode. */ - lfd, ti.__tcpi_sacked, ti.__tcpi_unacked); + DEBUG(D_interface) debug_printf("listen fd %d queue max %u curr %u\n", + p->fd, ti.__tcpi_sacked, ti.__tcpi_unacked); smtp_listen_backlog = ti.__tcpi_unacked; # endif -#endif } - accept_socket = accept(lfd, (struct sockaddr *)&accepted, &alen); +#endif + p->revents = 0; + accept_socket = accept(p->fd, (struct sockaddr *)&accepted, &alen); break; } - } } /* If select or accept has failed and this was not caused by an @@ -2586,7 +2627,7 @@ for (;;) #endif if (inetd_wait_timeout) last_connection_time = time(NULL); - handle_smtp_call(listen_sockets, listen_socket_count, accept_socket, + handle_smtp_call(fd_polls, listen_socket_count, accept_socket, (struct sockaddr *)&accepted); } } @@ -2601,10 +2642,8 @@ for (;;) else { - struct timeval tv; - tv.tv_sec = queue_interval; - tv.tv_usec = 0; - select(0, NULL, NULL, NULL, &tv); + struct pollfd p; + poll(&p, 0, queue_interval * 1000); handle_ending_processes(); } @@ -2629,8 +2668,7 @@ for (;;) { log_write(0, LOG_MAIN, "pid %d: SIGHUP received: re-exec daemon", getpid()); - close_daemon_sockets(daemon_notifier_fd, - listen_sockets, listen_socket_count); + close_daemon_sockets(daemon_notifier_fd, fd_polls, listen_socket_count); ALARM_CLR(0); signal(SIGHUP, SIG_IGN); sighup_argv[0] = exim_path;