From 52c15c8a5703d179125a054c9d25135153f6dc57 Mon Sep 17 00:00:00 2001 From: millert Date: Sun, 25 Oct 2015 21:30:11 +0000 Subject: [PATCH] Remove cron.pid support. We still want to avoid multiple crons running so verify that if the cron socket exists nothing is listening on it. OK tedu@ --- usr.sbin/cron/atrun.c | 4 +- usr.sbin/cron/cron.c | 38 ++------------ usr.sbin/cron/do_command.c | 3 +- usr.sbin/cron/misc.c | 101 ++++--------------------------------- 4 files changed, 18 insertions(+), 128 deletions(-) diff --git a/usr.sbin/cron/atrun.c b/usr.sbin/cron/atrun.c index d558e71de5b..1b427a6a489 100644 --- a/usr.sbin/cron/atrun.c +++ b/usr.sbin/cron/atrun.c @@ -1,4 +1,4 @@ -/* $OpenBSD: atrun.c,v 1.32 2015/10/23 18:42:55 tedu Exp $ */ +/* $OpenBSD: atrun.c,v 1.33 2015/10/25 21:30:11 millert Exp $ */ /* * Copyright (c) 2002-2003 Todd C. Miller @@ -248,8 +248,6 @@ run_job(atjob *job, char *atfile) return; } - acquire_daemonlock(1); /* close lock fd */ - /* * We don't want the main cron daemon to wait for our children-- * we will do it ourselves via waitpid(). diff --git a/usr.sbin/cron/cron.c b/usr.sbin/cron/cron.c index 1f2a25daab9..f38cc5e055a 100644 --- a/usr.sbin/cron/cron.c +++ b/usr.sbin/cron/cron.c @@ -1,4 +1,4 @@ -/* $OpenBSD: cron.c,v 1.54 2015/10/03 12:46:54 tedu Exp $ */ +/* $OpenBSD: cron.c,v 1.55 2015/10/25 21:30:11 millert Exp $ */ /* Copyright 1988,1990,1993,1994 by Paul Vixie * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") @@ -31,7 +31,6 @@ static void usage(void), sigchld_handler(int), sighup_handler(int), sigchld_reaper(void), - quit(int), parse_args(int c, char *v[]); static volatile sig_atomic_t got_sighup, got_sigchld; @@ -75,47 +74,27 @@ main(int argc, char *argv[]) (void) sigaction(SIGCHLD, &sact, NULL); sact.sa_handler = sighup_handler; (void) sigaction(SIGHUP, &sact, NULL); - sact.sa_handler = quit; - (void) sigaction(SIGINT, &sact, NULL); - (void) sigaction(SIGTERM, &sact, NULL); sact.sa_handler = SIG_IGN; (void) sigaction(SIGPIPE, &sact, NULL); - acquire_daemonlock(0); set_cron_uid(); set_cron_cwd(); + cronSock = open_socket(); + if (putenv("PATH="_PATH_DEFPATH) < 0) { log_it("CRON", getpid(), "DEATH", "can't malloc"); exit(EXIT_FAILURE); } if (NoFork == 0) { - switch (fork()) { - case -1: + if (daemon(1, 0) == -1) { log_it("CRON",getpid(),"DEATH","can't fork"); exit(EXIT_FAILURE); - break; - case 0: - /* child process */ - (void) setsid(); - if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) >= 0) { - (void) dup2(fd, STDIN_FILENO); - (void) dup2(fd, STDOUT_FILENO); - (void) dup2(fd, STDERR_FILENO); - if (fd != STDERR_FILENO) - (void) close(fd); - } - log_it("CRON",getpid(),"STARTUP",CRON_VERSION); - break; - default: - /* parent process should just die */ - _exit(EXIT_SUCCESS); } + log_it("CRON",getpid(),"STARTUP",CRON_VERSION); } - acquire_daemonlock(0); - cronSock = open_socket(); database.head = NULL; database.tail = NULL; database.mtime = 0; @@ -425,13 +404,6 @@ sigchld_handler(int x) got_sigchld = 1; } -static void -quit(int x) -{ - (void) unlink(_PATH_CRON_PID); - _exit(0); -} - static void sigchld_reaper(void) { diff --git a/usr.sbin/cron/do_command.c b/usr.sbin/cron/do_command.c index 7dad70e8390..17072b0d2e7 100644 --- a/usr.sbin/cron/do_command.c +++ b/usr.sbin/cron/do_command.c @@ -1,4 +1,4 @@ -/* $OpenBSD: do_command.c,v 1.49 2015/10/23 18:42:55 tedu Exp $ */ +/* $OpenBSD: do_command.c,v 1.50 2015/10/25 21:30:11 millert Exp $ */ /* Copyright 1988,1990,1993,1994 by Paul Vixie * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") @@ -38,7 +38,6 @@ do_command(entry *e, user *u) break; case 0: /* child process */ - acquire_daemonlock(1); child_process(e, u); _exit(EXIT_SUCCESS); break; diff --git a/usr.sbin/cron/misc.c b/usr.sbin/cron/misc.c index 41b79e179de..a2946a405a7 100644 --- a/usr.sbin/cron/misc.c +++ b/usr.sbin/cron/misc.c @@ -1,4 +1,4 @@ -/* $OpenBSD: misc.c,v 1.57 2015/10/23 18:42:55 tedu Exp $ */ +/* $OpenBSD: misc.c,v 1.58 2015/10/25 21:30:11 millert Exp $ */ /* Copyright 1988,1990,1993,1994 by Paul Vixie * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") @@ -138,93 +138,6 @@ set_cron_cwd(void) } } -/* acquire_daemonlock() - write our PID into /var/run/cron.pid, unless - * another daemon is already running, which we detect here. - * - * note: main() calls us twice; once before forking, once after. - * we maintain static storage of the file pointer so that we - * can rewrite our PID into _PATH_CRON_PID after the fork. - */ -void -acquire_daemonlock(int closeflag) -{ - static int fd = -1; - char buf[3*MAX_FNAME]; - const char *pidfile; - char *ep; - long otherpid; - ssize_t num; - - if (closeflag) { - /* close stashed fd for child so we don't leak it. */ - if (fd != -1) { - close(fd); - fd = -1; - } - return; - } - - if (fd == -1) { - pidfile = _PATH_CRON_PID; - fd = open(pidfile, - O_RDWR|O_CREAT|O_EXLOCK|O_NONBLOCK|O_CLOEXEC, 0644); - if (fd == -1) { - int save_errno = errno; - - if (errno != EWOULDBLOCK) { - snprintf(buf, sizeof buf, - "can't open or create %s: %s", pidfile, - strerror(save_errno)); - fprintf(stderr, "%s: %s\n", ProgramName, buf); - log_it("CRON", getpid(), "DEATH", buf); - exit(EXIT_FAILURE); - } - - /* couldn't lock the pid file, try to read existing. */ - bzero(buf, sizeof(buf)); - if ((fd = open(pidfile, O_RDONLY, 0)) >= 0 && - (num = read(fd, buf, sizeof(buf) - 1)) > 0 && - (otherpid = strtol(buf, &ep, 10)) > 0 && - ep != buf && *ep == '\n' && otherpid != LONG_MAX) { - snprintf(buf, sizeof buf, - "can't lock %s, otherpid may be %ld: %s", - pidfile, otherpid, strerror(save_errno)); - } else { - snprintf(buf, sizeof buf, - "can't lock %s, otherpid unknown: %s", - pidfile, strerror(save_errno)); - } - fprintf(stderr, "%s: %s\n", ProgramName, buf); - log_it("CRON", getpid(), "DEATH", buf); - exit(EXIT_FAILURE); - } - /* fd must be > STDERR_FILENO since we dup fd 0-2 to /dev/null */ - if (fd <= STDERR_FILENO) { - int newfd; - - newfd = fcntl(fd, F_DUPFD_CLOEXEC, STDERR_FILENO + 1); - if (newfd < 0) { - snprintf(buf, sizeof buf, - "can't dup pid fd: %s", strerror(errno)); - fprintf(stderr, "%s: %s\n", ProgramName, buf); - log_it("CRON", getpid(), "DEATH", buf); - exit(EXIT_FAILURE); - } - close(fd); - fd = newfd; - } - } - - snprintf(buf, sizeof(buf), "%ld\n", (long)getpid()); - (void) lseek(fd, 0, SEEK_SET); - num = write(fd, buf, strlen(buf)); - (void) ftruncate(fd, num); - - /* abandon fd even though the file is open. we need to keep - * it open and locked, but we don't need the handles elsewhere. - */ -} - /* get_char(file) : like getc() but increment LineNumber on newlines */ int @@ -490,8 +403,9 @@ int swap_gids_back() { return (setegid(save_egid)); } * If the local pointer is non-NULL it *must* point to a local copy. */ -/* void open_socket(void) +/* int open_socket(void) * opens a UNIX domain socket that crontab uses to poke cron. + * If the socket is already in use, return an error. */ int open_socket(void) @@ -528,10 +442,17 @@ open_socket(void) log_it("CRON", getpid(), "DEATH", "path too long"); exit(EXIT_FAILURE); } - unlink(s_un.sun_path); s_un.sun_family = AF_UNIX; s_un.sun_len = SUN_LEN(&s_un); + if (connect(sock, (struct sockaddr *)&s_un, sizeof(s_un)) == 0) { + fprintf(stderr, "%s: already running\n", ProgramName); + log_it("CRON", getpid(), "DEATH", "already running"); + exit(EXIT_FAILURE); + } + if (errno != ENOENT) + unlink(s_un.sun_path); + omask = umask(007); if (bind(sock, (struct sockaddr *)&s_un, sizeof(s_un))) { fprintf(stderr, "%s: can't bind socket: %s\n", -- 2.20.1