X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprocess.c;h=9d1c489ff88fbd1bbe2f583b40df802444a67649;hp=f221a9aa1c17537c67504fd7bfde9859ebb11dcc;hb=627f7c22b447bd464b536cd016278545674df93d;hpb=2764532ea72200d0a27ad2d79e6e299c00c62404 diff --git a/src/process.c b/src/process.c index f221a9aa..9d1c489f 100644 --- a/src/process.c +++ b/src/process.c @@ -1,7 +1,7 @@ /* process.c -- process management functions - Copyright (C) 1999,2000 Ivo Timmermans , - 2000 Guus Sliepen + Copyright (C) 1999-2002 Ivo Timmermans , + 2000-2002 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,67 +17,179 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: process.c,v 1.1.2.1 2000/11/16 17:54:28 zarq Exp $ + $Id: process.c,v 1.1.2.41 2002/06/21 10:11:13 guus Exp $ */ #include "config.h" -#include - -/* A list containing all our children */ -list_t *child_pids; +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include "conf.h" +#include "process.h" +#include "subnet.h" +#include "device.h" +#include "connection.h" +#include "device.h" + +#include "system.h" /* If zero, don't detach from the terminal. */ int do_detach = 1; +extern char *identname; +extern char *pidfilename; +extern char **g_argv; + +sigset_t emptysigset; + +static int saved_debug_lvl = 0; + +extern int sighup; +extern int sigalrm; +extern int do_purge; + +void memory_full(int size) +{ + syslog(LOG_ERR, _("Memory exhausted (couldn't allocate %d bytes), exitting."), size); + cp_trace(); + exit(1); +} + +/* Some functions the less gifted operating systems might lack... */ + +#ifndef HAVE_FCLOSEALL +int fcloseall(void) +{ + fflush(stdin); + fflush(stdout); + fflush(stderr); + fclose(stdin); + fclose(stdout); + fclose(stderr); + return 0; +} +#endif + /* - Detach from current terminal, write pidfile, kill parent + Close network connections, and terminate neatly */ -int detach(void) +void cleanup_and_exit(int c) { - int fd; - pid_t pid; +cp + close_network_connections(); - if(do_detach) + if(debug_lvl > DEBUG_NOTHING) + dump_device_stats(); + + syslog(LOG_NOTICE, _("Terminating")); + + closelog(); + exit(c); +} + +/* + check for an existing tinc for this net, and write pid to pidfile +*/ +int write_pidfile(void) +{ + int pid; +cp + if((pid = check_pid(pidfilename))) { - ppid = getpid(); + if(netname) + fprintf(stderr, _("A tincd is already running for net `%s' with pid %d.\n"), + netname, pid); + else + fprintf(stderr, _("A tincd is already running with pid %d.\n"), pid); + return 1; + } - if((pid = fork()) < 0) - { - perror("fork"); - return -1; - } - if(pid) /* parent process */ - { - signal(SIGTERM, parent_exit); - sleep(600); /* wait 10 minutes */ - exit(1); - } + /* if it's locked, write-protected, or whatever */ + if(!write_pid(pidfilename)) + return 1; +cp + return 0; +} + +/* + kill older tincd for this net +*/ +int kill_other(int signal) +{ + int pid; +cp + if(!(pid = read_pid(pidfilename))) + { + if(netname) + fprintf(stderr, _("No other tincd is running for net `%s'.\n"), netname); + else + fprintf(stderr, _("No other tincd is running.\n")); + return 1; + } + + errno = 0; /* No error, sometimes errno is only changed on error */ + /* ESRCH is returned when no process with that pid is found */ + if(kill(pid, signal) && errno == ESRCH) + { + if(netname) + fprintf(stderr, _("The tincd for net `%s' is no longer running. "), netname); + else + fprintf(stderr, _("The tincd is no longer running. ")); + + fprintf(stderr, _("Removing stale lock file.\n")); + remove_pid(pidfilename); } +cp + return 0; +} + +/* + Detach from current terminal, write pidfile, kill parent +*/ +int detach(void) +{ +cp + setup_signals(); + + /* First check if we can open a fresh new pidfile */ if(write_pidfile()) return -1; + /* If we succeeded in doing that, detach */ + + closelog(); + if(do_detach) { - if((fd = open("/dev/tty", O_RDWR)) >= 0) + if(daemon(0, 0) < 0) { - if(ioctl(fd, TIOCNOTTY, NULL)) - { - perror("ioctl"); - return -1; - } - close(fd); + fprintf(stderr, _("Couldn't detach from terminal: %s"), strerror(errno)); + return -1; } - if(setsid() < 0) - return -1; - - kill(ppid, SIGTERM); + /* Now UPDATE the pid in the pidfile, because we changed it... */ + + if(!write_pid(pidfilename)) + return -1; } - chdir("/"); /* avoid keeping a mointpoint busy */ - openlog(identname, LOG_CONS | LOG_PID, LOG_DAEMON); if(debug_lvl > DEBUG_NOTHING) @@ -87,7 +199,7 @@ int detach(void) syslog(LOG_NOTICE, _("tincd %s starting"), VERSION); xalloc_fail_func = memory_full; - +cp return 0; } @@ -95,75 +207,47 @@ int detach(void) Execute the program name, with sane environment. All output will be redirected to syslog. */ -void _execute_script(const char *name) +void _execute_script(const char *scriptname) __attribute__ ((noreturn)); +void _execute_script(const char *scriptname) { - int error = 0; - char *scriptname; char *s; - int fd; +cp +#ifdef HAVE_UNSETENV + unsetenv("NETNAME"); + unsetenv("DEVICE"); + unsetenv("INTERFACE"); +#endif if(netname) { asprintf(&s, "NETNAME=%s", netname); putenv(s); /* Don't free s! see man 3 putenv */ } -#ifdef HAVE_UNSETENV - else + + if(device) { - unsetenv("NETNAME"); + asprintf(&s, "DEVICE=%s", device); + putenv(s); /* Don't free s! see man 3 putenv */ } -#endif - if(chdir(confbase) < 0) - /* This cannot fail since we already read config files from this - directory. - Guus */ - /* Yes this can fail, somebody could have removed this directory - when we didn't pay attention. - Ivo */ + if(interface) { - if(chdir("/") < 0) - /* Now if THIS fails, something wicked is going on. - Ivo */ - syslog(LOG_ERR, _("Couldn't chdir to `/': %m")); - - /* Continue anyway. */ + asprintf(&s, "INTERFACE=%s", interface); + putenv(s); /* Don't free s! see man 3 putenv */ } - - asprintf(&scriptname, "%s/%s", confbase, name); + chdir("/"); + /* Close all file descriptors */ - closelog(); + closelog(); /* <- this means we cannot use syslog() here anymore! */ fcloseall(); - /* Open standard input */ - if(open("/dev/null", O_RDONLY) < 0) - { - syslog(LOG_ERR, _("Opening `/dev/null' failed: %m")); - error = 1; - } - - if(!error) - { - /* Standard output directly goes to syslog */ - openlog(name, LOG_CONS | LOG_PID, LOG_DAEMON); - /* Standard error as well */ - if(dup2(1, 2) < 0) - { - syslog(LOG_ERR, _("System call `%s' failed: %m"), - "dup2"); - error = 1; - } - } - - if(error && debug_lvl > 1) - syslog(LOG_INFO, _("This means that any output the script generates will not be shown in syslog.")); - execl(scriptname, NULL); /* No return on success */ - - if(errno != ENOENT) /* Ignore if the file does not exist */ - syslog(LOG_WARNING, _("Error executing `%s': %m"), scriptname); - /* No need to free things */ - exit(0); + openlog("tinc", LOG_CONS | LOG_PID, LOG_DAEMON); + syslog(LOG_ERR, _("Could not execute `%s': %s"), scriptname, strerror(errno)); + exit(errno); } /* @@ -172,67 +256,67 @@ void _execute_script(const char *name) int execute_script(const char *name) { pid_t pid; + int status; + struct stat s; + char *scriptname; +cp + asprintf(&scriptname, "%s/%s", confbase, name); + + /* First check if there is a script */ + + if(stat(scriptname, &s)) + return 0; if((pid = fork()) < 0) { - syslog(LOG_ERR, _("System call `%s' failed: %m"), - "fork"); + syslog(LOG_ERR, _("System call `%s' failed: %s"), "fork", strerror(errno)); return -1; } if(pid) { - list_append(child_pids, pid); - return 0; + if(debug_lvl >= DEBUG_STATUS) + syslog(LOG_INFO, _("Executing script %s"), name); + + free(scriptname); + + if(waitpid(pid, &status, 0) == pid) + { + if(WIFEXITED(status)) /* Child exited by itself */ + { + if(WEXITSTATUS(status)) + { + syslog(LOG_ERR, _("Process %d (%s) exited with non-zero status %d"), pid, name, WEXITSTATUS(status)); + return -1; + } + else + return 0; + } + else if(WIFSIGNALED(status)) /* Child was killed by a signal */ + { + syslog(LOG_ERR, _("Process %d (%s) was killed by signal %d (%s)"), + pid, name, WTERMSIG(status), strsignal(WTERMSIG(status))); + return -1; + } + else /* Something strange happened */ + { + syslog(LOG_ERR, _("Process %d (%s) terminated abnormally"), pid, name); + return -1; + } + } + else + { + syslog(LOG_ERR, _("System call `%s' failed: %s"), "waitpid", strerror(errno)); + return -1; + } } - +cp /* Child here */ - _execute_script(name); -} - -/* - Check a child (the pointer data is actually an integer, the PID of - that child. A non-zero return value means that the child has exited - and can be removed from our list. -*/ -int check_child(void *data) -{ - pid_t pid; - int status; - - pid = (pid_t) data; - pid = waitpid(pid, &status, WNOHANG); - if(WIFEXITED(status)) - { - if(WIFSIGNALED(status)) /* Child was killed by a signal */ - { - syslog(LOG_ERR, _("Child with PID %d was killed by signal %d (%s)"), - pid, WTERMSIG(status), strsignal(WTERMSIG(status))); - return -1; - } - if(WEXITSTATUS(status) != 0) - { - syslog(LOG_INFO, _("Child with PID %d exited with code %d"), - WEXITSTATUS(status)); - } - return -1; - } - - /* Child is still running */ - return 0; -} - -/* - Check the status of all our children. -*/ -void check_children(void) -{ - list_forall_nodes(child_pids, check_child); + _execute_script(scriptname); } - /* Signal handlers. */ @@ -255,22 +339,29 @@ sigquit_handler(int a) } RETSIGTYPE -sigsegv_square(int a) +fatal_signal_square(int a) { - syslog(LOG_ERR, _("Got another SEGV signal: not restarting")); - exit(0); + syslog(LOG_ERR, _("Got another fatal signal %d (%s): not restarting."), a, strsignal(a)); + cp_trace(); + exit(1); } RETSIGTYPE -sigsegv_handler(int a) +fatal_signal_handler(int a) { - syslog(LOG_ERR, _("Got SEGV signal")); + struct sigaction act; + syslog(LOG_ERR, _("Got fatal signal %d (%s)"), a, strsignal(a)); cp_trace(); if(do_detach) { syslog(LOG_NOTICE, _("Trying to re-execute in 5 seconds...")); - signal(SIGSEGV, sigsegv_square); + + act.sa_handler = fatal_signal_square; + act.sa_mask = emptysigset; + act.sa_flags = 0; + sigaction(SIGSEGV, &act, NULL); + close_network_connections(); sleep(5); remove_pid(pidfilename); @@ -279,7 +370,7 @@ sigsegv_handler(int a) else { syslog(LOG_NOTICE, _("Not restarting.")); - exit(0); + exit(1); } } @@ -293,56 +384,123 @@ sighup_handler(int a) RETSIGTYPE sigint_handler(int a) +{ + if(saved_debug_lvl) + { + syslog(LOG_NOTICE, _("Reverting to old debug level (%d)"), + saved_debug_lvl); + debug_lvl = saved_debug_lvl; + saved_debug_lvl = 0; + } + else + { + syslog(LOG_NOTICE, _("Temporarily setting debug level to 5. Kill me with SIGINT again to go back to level %d."), + debug_lvl); + saved_debug_lvl = debug_lvl; + debug_lvl = 5; + } +} + +RETSIGTYPE +sigalrm_handler(int a) { if(debug_lvl > DEBUG_NOTHING) - syslog(LOG_NOTICE, _("Got INT signal, exiting")); - cleanup_and_exit(0); + syslog(LOG_NOTICE, _("Got ALRM signal")); + sigalrm = 1; } RETSIGTYPE sigusr1_handler(int a) { - dump_conn_list(); + dump_connections(); } RETSIGTYPE sigusr2_handler(int a) { - dump_subnet_list(); + dump_device_stats(); + dump_nodes(); + dump_edges(); + dump_subnets(); +} + +RETSIGTYPE +sigwinch_handler(int a) +{ + extern int do_purge; + do_purge = 1; } RETSIGTYPE -sighuh(int a) +unexpected_signal_handler(int a) { syslog(LOG_WARNING, _("Got unexpected signal %d (%s)"), a, strsignal(a)); cp_trace(); } +RETSIGTYPE +ignore_signal_handler(int a) +{ + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + syslog(LOG_DEBUG, _("Ignored signal %d (%s)"), a, strsignal(a)); + cp_trace(); + } +} + +struct { + int signal; + void (*handler)(int); +} sighandlers[] = { + { SIGHUP, sighup_handler }, + { SIGTERM, sigterm_handler }, + { SIGQUIT, sigquit_handler }, + { SIGSEGV, fatal_signal_handler }, + { SIGBUS, fatal_signal_handler }, + { SIGILL, fatal_signal_handler }, + { SIGPIPE, ignore_signal_handler }, + { SIGINT, sigint_handler }, + { SIGUSR1, sigusr1_handler }, + { SIGUSR2, sigusr2_handler }, + { SIGCHLD, ignore_signal_handler }, + { SIGALRM, sigalrm_handler }, + { SIGWINCH, sigwinch_handler }, + { 0, NULL } +}; + void setup_signals(void) { int i; + struct sigaction act; - for(i=0;i<32;i++) - signal(i,sighuh); - - if(signal(SIGTERM, SIG_IGN) != SIG_ERR) - signal(SIGTERM, sigterm_handler); - if(signal(SIGQUIT, SIG_IGN) != SIG_ERR) - signal(SIGQUIT, sigquit_handler); - if(signal(SIGSEGV, SIG_IGN) != SIG_ERR) - signal(SIGSEGV, sigsegv_handler); - if(signal(SIGHUP, SIG_IGN) != SIG_ERR) - signal(SIGHUP, sighup_handler); - signal(SIGPIPE, SIG_IGN); - if(signal(SIGINT, SIG_IGN) != SIG_ERR) - signal(SIGINT, sigint_handler); - signal(SIGUSR1, sigusr1_handler); - signal(SIGUSR2, sigusr2_handler); - signal(SIGCHLD, SIG_IGN); -} + sigemptyset(&emptysigset); + act.sa_handler = NULL; + act.sa_mask = emptysigset; + act.sa_flags = 0; -RETSIGTYPE parent_exit(int a) -{ - exit(0); + /* Set a default signal handler for every signal, errors will be + ignored. */ + for(i = 0; i < NSIG; i++) + { + if(!do_detach) + act.sa_handler = SIG_DFL; + else + act.sa_handler = unexpected_signal_handler; + sigaction(i, &act, NULL); + } + + /* If we didn't detach, allow coredumps */ + if(!do_detach) + sighandlers[3].handler = SIG_DFL; + + /* Then, for each known signal that we want to catch, assign a + handler to the signal, with error checking this time. */ + for(i = 0; sighandlers[i].signal; i++) + { + act.sa_handler = sighandlers[i].handler; + if(sigaction(sighandlers[i].signal, &act, NULL) < 0) + fprintf(stderr, _("Installing signal handler for signal %d (%s) failed: %s\n"), + sighandlers[i].signal, strsignal(sighandlers[i].signal), strerror(errno)); + } }