meillo@0: /*  MasqMail
meillo@0:     Copyright (C) 1999/2000 Oliver Kurth
meillo@0: 
meillo@0:     This program is free software; you can redistribute it and/or modify
meillo@0:     it under the terms of the GNU General Public License as published by
meillo@0:     the Free Software Foundation; either version 2 of the License, or
meillo@0:     (at your option) any later version.
meillo@0: 
meillo@0:     This program is distributed in the hope that it will be useful,
meillo@0:     but WITHOUT ANY WARRANTY; without even the implied warranty of
meillo@0:     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
meillo@0:     GNU General Public License for more details.
meillo@0: 
meillo@0:     You should have received a copy of the GNU General Public License
meillo@0:     along with this program; if not, write to the Free Software
meillo@0:     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
meillo@0: */
meillo@0: 
meillo@0: #include "masqmail.h"
meillo@0: #include <sys/wait.h>
meillo@0: #include <sys/types.h>
meillo@0: 
meillo@0: static int volatile sighup_seen = 0;
meillo@0: 
meillo@10: static void
meillo@10: sighup_handler(int sig)
meillo@0: {
meillo@10: 	sighup_seen = 1;
meillo@10: 	signal(SIGHUP, sighup_handler);
meillo@0: }
meillo@0: 
meillo@10: static void
meillo@10: sigchld_handler(int sig)
meillo@0: {
meillo@10: 	pid_t pid;
meillo@10: 	int status;
meillo@10: 
meillo@10: 	pid = waitpid(0, &status, 0);
meillo@10: 	if (pid > 0) {
meillo@10: 		if (WEXITSTATUS(status) != EXIT_SUCCESS)
meillo@10: 			logwrite(LOG_WARNING, "process %d exited with %d\n", pid, WEXITSTATUS(status));
meillo@10: 		if (WIFSIGNALED(status))
meillo@10: 			logwrite(LOG_WARNING, "process with pid %d got signal: %d\n", pid, WTERMSIG(status));
meillo@10: 	}
meillo@10: 	signal(SIGCHLD, sigchld_handler);
meillo@0: }
meillo@0: 
meillo@0: #ifdef ENABLE_SMTP_SERVER
meillo@10: void
meillo@10: accept_connect(int listen_sock, int sock, struct sockaddr_in *sock_addr)
meillo@0: {
meillo@10: 	pid_t pid;
meillo@10: 	int dup_sock = dup(sock);
meillo@10: 	FILE *out, *in;
meillo@10: 	gchar *rem_host;
meillo@10: 	gchar *ident = NULL;
meillo@0: 
meillo@10: 	rem_host = g_strdup(inet_ntoa(sock_addr->sin_addr));
meillo@0: #ifdef ENABLE_IDENT
meillo@10: 	{
meillo@10: 		gchar *id = NULL;
meillo@10: 		if ((id = (gchar *) ident_id(sock, 60))) {
meillo@10: 			ident = g_strdup(id);
meillo@10: 		}
meillo@10: 		logwrite(LOG_NOTICE, "connect from host %s, port %hd ident=%s\n", rem_host,
meillo@10: 		         ntohs(sock_addr->sin_port), ident ? ident : "(unknown)");
meillo@10: 	}
meillo@0: #else
meillo@10: 	logwrite(LOG_NOTICE, "connect from host %s, port %hd\n", rem_host, ntohs(sock_addr->sin_port));
meillo@0: #endif
meillo@0: 
meillo@10: 	// start child for connection:
meillo@10: 	signal(SIGCHLD, sigchld_handler);
meillo@10: 	pid = fork();
meillo@10: 	if (pid == 0) {
meillo@10: 		close(listen_sock);
meillo@10: 		out = fdopen(sock, "w");
meillo@10: 		in = fdopen(dup_sock, "r");
meillo@0: 
meillo@10: 		smtp_in(in, out, rem_host, ident);
meillo@0: 
meillo@10: 		_exit(EXIT_SUCCESS);
meillo@10: 	} else if (pid < 0) {
meillo@10: 		logwrite(LOG_WARNING, "could not fork for incoming smtp connection: %s\n", strerror(errno));
meillo@10: 	}
meillo@0: #ifdef ENABLE_IDENT
meillo@10: 	if (ident != NULL)
meillo@10: 		g_free(ident);
meillo@0: #endif
meillo@0: 
meillo@10: 	close(sock);
meillo@10: 	close(dup_sock);
meillo@0: }
meillo@10: #endif  /*ifdef ENABLE_SMTP_SERVER */
meillo@0: 
meillo@10: void
meillo@10: listen_port(GList * iface_list, gint qival, char *argv[])
meillo@0: {
meillo@10: 	int i;
meillo@10: 	fd_set active_fd_set, read_fd_set;
meillo@10: 	struct timeval tm;
meillo@10: 	time_t time_before, time_now;
meillo@10: 	struct sockaddr_in clientname;
meillo@10: 	size_t size;
meillo@10: 	GList *node, *node_next;
meillo@10: 	int sel_ret;
meillo@0: 
meillo@10: 	/* Create the sockets and set them up to accept connections. */
meillo@10: 	FD_ZERO(&active_fd_set);
meillo@0: #ifdef ENABLE_SMTP_SERVER
meillo@10: 	for (node = g_list_first(iface_list); node; node = node_next) {
meillo@10: 		interface *iface = (interface *) (node->data);
meillo@10: 		int sock;
meillo@0: 
meillo@10: 		node_next = g_list_next(node);
meillo@10: 		if ((sock = make_server_socket(iface)) < 0) {
meillo@10: 			iface_list = g_list_remove_link(iface_list, node);
meillo@10: 			g_list_free_1(node);
meillo@10: 			continue;
meillo@10: 		}
meillo@10: 		if (listen(sock, 1) < 0) {
meillo@10: 			logwrite(LOG_ALERT, "listen: (terminating): %s\n", strerror(errno));
meillo@10: 			exit(EXIT_FAILURE);
meillo@10: 		}
meillo@10: 		logwrite(LOG_NOTICE, "listening on interface %s:%d\n", iface->address, iface->port);
meillo@10: 		DEBUG(5) debugf("sock = %d\n", sock);
meillo@10: 		FD_SET(sock, &active_fd_set);
meillo@10: 	}
meillo@0: #endif
meillo@0: 
meillo@10: 	/* setup handler for HUP signal: */
meillo@10: 	signal(SIGHUP, sighup_handler);
meillo@10: 	signal(SIGCHLD, sigchld_handler);
meillo@0: 
meillo@10: 	/* now that we have our socket(s),
meillo@10: 	   we can give up root privileges */
meillo@10: 	if (!conf.run_as_user) {
meillo@10: 		if (setegid(conf.mail_gid) != 0) {
meillo@10: 			logwrite(LOG_ALERT, "could not change gid to %d: %s\n", conf.mail_gid, strerror(errno));
meillo@10: 			exit(EXIT_FAILURE);
meillo@10: 		}
meillo@10: 		if (seteuid(conf.mail_uid) != 0) {
meillo@10: 			logwrite(LOG_ALERT, "could not change uid to %d: %s\n", conf.mail_uid, strerror(errno));
meillo@10: 			exit(EXIT_FAILURE);
meillo@10: 		}
meillo@10: 	}
meillo@0: 
meillo@10: 	/*  sel_ret = 0; */
meillo@10: 	time(&time_before);
meillo@10: 	time_before -= qival;
meillo@10: 	sel_ret = -1;
meillo@0: 
meillo@10: 	while (1) {
meillo@0: 
meillo@10: 		/* if we were interrupted by an incoming connection (or a signal)
meillo@10: 		   we have to recalculate the time until the next queue run should
meillo@10: 		   occur. select may put a value into tm, but doc for select() says
meillo@10: 		   we should not use it. */
meillo@10: 		if (qival > 0) {
meillo@10: 			time(&time_now);
meillo@10: 			if (sel_ret == 0) {  /* we are either just starting or did a queue run */
meillo@10: 				tm.tv_sec = qival;
meillo@10: 				tm.tv_usec = 0;
meillo@10: 				time_before = time_now;
meillo@10: 			} else {
meillo@10: 				tm.tv_sec = qival - (time_now - time_before);
meillo@10: 				tm.tv_usec = 0;
meillo@0: 
meillo@10: 				/* race condition, very unlikely (but possible): */
meillo@10: 				if (tm.tv_sec < 0)
meillo@10: 					tm.tv_sec = 0;
meillo@10: 			}
meillo@10: 		}
meillo@10: 		/* Block until input arrives on one or more active sockets,
meillo@10: 		   or signal arrives,
meillo@10: 		   or queuing interval time elapsed (if qival > 0) */
meillo@10: 		read_fd_set = active_fd_set;
meillo@10: 		if ((sel_ret = select(FD_SETSIZE, &read_fd_set, NULL, NULL, qival > 0 ? &tm : NULL)) < 0) {
meillo@10: 			if (errno != EINTR) {
meillo@10: 				logwrite(LOG_ALERT, "select: (terminating): %s\n", strerror(errno));
meillo@10: 				exit(EXIT_FAILURE);
meillo@10: 			} else {
meillo@10: 				if (sighup_seen) {
meillo@10: 					logwrite(LOG_NOTICE, "HUP signal received. Restarting daemon\n");
meillo@0: 
meillo@10: 					for (i = 0; i < FD_SETSIZE; i++)
meillo@10: 						if (FD_ISSET(i, &active_fd_set))
meillo@10: 							close(i);
meillo@0: 
meillo@10: 					execv(argv[0], &(argv[0]));
meillo@10: 					logwrite(LOG_ALERT, "restarting failed: %s\n", strerror(errno));
meillo@10: 					exit(EXIT_FAILURE);
meillo@10: 				}
meillo@10: 			}
meillo@10: 		} else if (sel_ret > 0) {
meillo@10: #ifdef ENABLE_SMTP_SERVER
meillo@10: 			for (i = 0; i < FD_SETSIZE; i++) {
meillo@10: 				if (FD_ISSET(i, &read_fd_set)) {
meillo@10: 					int sock = i;
meillo@10: 					int new;
meillo@10: 					size = sizeof(clientname);
meillo@10: 					new = accept(sock, (struct sockaddr *) &clientname, &size);
meillo@10: 					if (new < 0) {
meillo@10: 						logwrite(LOG_ALERT, "accept: (ignoring): %s\n", strerror(errno));
meillo@10: 					} else
meillo@10: 						accept_connect(sock, new, &clientname);
meillo@10: 				}
meillo@10: 			}
meillo@10: #else
meillo@10: 			;
meillo@10: #endif
meillo@10: 		} else {
meillo@10: 			/* If select returns 0, the interval time has elapsed.
meillo@10: 			   We start a new queue runner process */
meillo@10: 			int pid;
meillo@10: 			signal(SIGCHLD, sigchld_handler);
meillo@10: 			if ((pid = fork()) == 0) {
meillo@10: 				queue_run();
meillo@10: 
meillo@10: 				_exit(EXIT_SUCCESS);
meillo@10: 			} else if (pid < 0) {
meillo@10: 				logwrite(LOG_ALERT, "could not fork for queue run");
meillo@10: 			}
meillo@10: 		}
meillo@0: 	}
meillo@0: }