X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=debianutils%2Fstart_stop_daemon.c;h=c8b7fa8f21d912b3cfdb0ef735b350cdcb2359da;hb=9a4100cf53f75356854ce752374babf8135c3f42;hp=cf792709c4aa35036d6c0949b4000e7a182b9164;hpb=1caca34aa67b2f267d0049d17e5430ca9c58ac3f;p=oweals%2Fbusybox.git diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c index cf792709c..c8b7fa8f2 100644 --- a/debianutils/start_stop_daemon.c +++ b/debianutils/start_stop_daemon.c @@ -5,102 +5,271 @@ * Written by Marek Michalkiewicz , * Adapted for busybox David Kimdon * - * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + * Licensed under GPLv2 or later, see file LICENSE in this source tree. */ -/* NB: we have a problem here with /proc/NN/exe usage, similar to - * one fixed in killall/pidof */ +/* +This is how it is supposed to work: + +start-stop-daemon [OPTIONS] [--start|--stop] [[--] arguments...] + +One (only) of these must be given: + -S,--start Start + -K,--stop Stop + +Search for matching processes. +If --stop is given, stop all matching processes (by sending a signal). +If --start is given, start a new process unless a matching process was found. + +Options controlling process matching +(if multiple conditions are specified, all must match): + -u,--user USERNAME|UID Only consider this user's processes + -n,--name PROCESS_NAME Look for processes by matching PROCESS_NAME + with comm field in /proc/$PID/stat. + Only basename is compared: + "ntpd" == "./ntpd" == "/path/to/ntpd". +[TODO: can PROCESS_NAME be a full pathname? Should we require full match then +with /proc/$PID/exe or argv[0] (comm can't be matched, it never contains path)] + -x,--exec EXECUTABLE Look for processes that were started with this + command in /proc/$PID/exe and /proc/$PID/cmdline + (/proc/$PID/cmdline is a bbox extension) + Unlike -n, we match against the full path: + "ntpd" != "./ntpd" != "/path/to/ntpd" + -p,--pidfile PID_FILE Look for processes with PID from this file + +Options which are valid for --start only: + -x,--exec EXECUTABLE Program to run (1st arg of execvp). Mandatory. + -a,--startas NAME argv[0] (defaults to EXECUTABLE) + -b,--background Put process into background + -N,--nicelevel N Add N to process' nice level + -c,--chuid USER[:[GRP]] Change to specified user [and group] + -m,--make-pidfile Write PID to the pidfile + (both -m and -p must be given!) + +Options which are valid for --stop only: + -s,--signal SIG Signal to send (default:TERM) + -t,--test Exit with status 0 if process is found + (we don't actually start or stop daemons) + +Misc options: + -o,--oknodo Exit with status 0 if nothing is done + -q,--quiet Quiet + -v,--verbose Verbose +*/ +//config:config START_STOP_DAEMON +//config: bool "start-stop-daemon (12 kb)" +//config: default y +//config: help +//config: start-stop-daemon is used to control the creation and +//config: termination of system-level processes, usually the ones +//config: started during the startup of the system. +//config: +//config:config FEATURE_START_STOP_DAEMON_LONG_OPTIONS +//config: bool "Enable long options" +//config: default y +//config: depends on START_STOP_DAEMON && LONG_OPTS +//config: +//config:config FEATURE_START_STOP_DAEMON_FANCY +//config: bool "Support additional arguments" +//config: default y +//config: depends on START_STOP_DAEMON +//config: help +//config: -o|--oknodo ignored since we exit with 0 anyway +//config: -v|--verbose +//config: -N|--nicelevel N + +//applet:IF_START_STOP_DAEMON(APPLET_ODDNAME(start-stop-daemon, start_stop_daemon, BB_DIR_SBIN, BB_SUID_DROP, start_stop_daemon)) +/* not NOEXEC: uses bb_common_bufsiz1 */ + +//kbuild:lib-$(CONFIG_START_STOP_DAEMON) += start_stop_daemon.o + +//usage:#define start_stop_daemon_trivial_usage +//usage: "[OPTIONS] [-S|-K] ... [-- ARGS...]" +//usage:#define start_stop_daemon_full_usage "\n\n" +//usage: "Search for matching processes, and then\n" +//usage: "-K: stop all matching processes\n" +//usage: "-S: start a process unless a matching process is found\n" +//usage: "\nProcess matching:" +//usage: "\n -u USERNAME|UID Match only this user's processes" +//usage: "\n -n NAME Match processes with NAME" +//usage: "\n in comm field in /proc/PID/stat" +//usage: "\n -x EXECUTABLE Match processes with this command" +//usage: "\n command in /proc/PID/cmdline" +//usage: "\n -p FILE Match a process with PID from FILE" +//usage: "\n All specified conditions must match" +//usage: "\n-S only:" +//usage: "\n -x EXECUTABLE Program to run" +//usage: "\n -a NAME Zeroth argument" +//usage: "\n -b Background" +//usage: IF_FEATURE_START_STOP_DAEMON_FANCY( +//usage: "\n -N N Change nice level" +//usage: ) +//usage: "\n -c USER[:[GRP]] Change user/group" +//usage: "\n -m Write PID to pidfile specified by -p" +//usage: "\n-K only:" +//usage: "\n -s SIG Signal to send" +//usage: "\n -t Match only, exit with 0 if found" +//usage: "\nOther:" +//usage: IF_FEATURE_START_STOP_DAEMON_FANCY( +//usage: "\n -o Exit with status 0 if nothing is done" +//usage: "\n -v Verbose" +//usage: ) +//usage: "\n -q Quiet" -#include #include /* Override ENABLE_FEATURE_PIDFILE */ #define WANT_PIDFILE 1 #include "libbb.h" - -static int signal_nr = 15; -static int user_id = -1; -static char *userspec; -static char *cmdname; -static char *execname; -static char *pidfile; -static smallint quiet; +#include "common_bufsiz.h" struct pid_list { struct pid_list *next; pid_t pid; }; -static struct pid_list *found; +enum { + CTX_STOP = (1 << 0), + CTX_START = (1 << 1), + OPT_BACKGROUND = (1 << 2), // -b + OPT_QUIET = (1 << 3), // -q + OPT_TEST = (1 << 4), // -t + OPT_MAKEPID = (1 << 5), // -m + OPT_a = (1 << 6), // -a + OPT_n = (1 << 7), // -n + OPT_s = (1 << 8), // -s + OPT_u = (1 << 9), // -u + OPT_c = (1 << 10), // -c + OPT_x = (1 << 11), // -x + OPT_p = (1 << 12), // -p + OPT_OKNODO = (1 << 13) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -o + OPT_VERBOSE = (1 << 14) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -v + OPT_NICELEVEL = (1 << 15) * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -N +}; +#define QUIET (option_mask32 & OPT_QUIET) +#define TEST (option_mask32 & OPT_TEST) + +struct globals { + struct pid_list *found_procs; + char *userspec; + char *cmdname; + char *execname; + char *pidfile; + char *execname_cmpbuf; + unsigned execname_sizeof; + int user_id; + smallint signal_nr; +} FIX_ALIASING; +#define G (*(struct globals*)bb_common_bufsiz1) +#define userspec (G.userspec ) +#define cmdname (G.cmdname ) +#define execname (G.execname ) +#define pidfile (G.pidfile ) +#define user_id (G.user_id ) +#define signal_nr (G.signal_nr ) +#define INIT_G() do { \ + setup_common_bufsiz(); \ + user_id = -1; \ + signal_nr = 15; \ +} while (0) + +#ifdef OLDER_VERSION_OF_X +/* -x,--exec EXECUTABLE + * Look for processes with matching /proc/$PID/exe. + * Match is performed using device+inode. + */ +static int pid_is_exec(pid_t pid) +{ + struct stat st; + char buf[sizeof("/proc/%u/exe") + sizeof(int)*3]; -static int pid_is_exec(pid_t pid, const char *name) + sprintf(buf, "/proc/%u/exe", (unsigned)pid); + if (stat(buf, &st) < 0) + return 0; + if (st.st_dev == execstat.st_dev + && st.st_ino == execstat.st_ino) + return 1; + return 0; +} +#endif + +static int pid_is_exec(pid_t pid) { - char buf[sizeof("/proc//exe") + sizeof(int)*3]; - char *execbuf; - int n; + ssize_t bytes; + char buf[sizeof("/proc/%u/cmdline") + sizeof(int)*3]; + char *procname, *exelink; + int match; + + procname = buf + sprintf(buf, "/proc/%u/exe", (unsigned)pid) - 3; + + exelink = xmalloc_readlink(buf); + match = (exelink && strcmp(execname, exelink) == 0); + free(exelink); + if (match) + return match; + + strcpy(procname, "cmdline"); + bytes = open_read_close(buf, G.execname_cmpbuf, G.execname_sizeof); + if (bytes > 0) { + G.execname_cmpbuf[bytes] = '\0'; + return strcmp(execname, G.execname_cmpbuf) == 0; + } + return 0; +} - sprintf(buf, "/proc/%u/exe", pid); - n = strlen(name) + 1; - execbuf = xzalloc(n + 1); - readlink(buf, execbuf, n); +static int pid_is_name(pid_t pid) +{ + /* /proc/PID/stat is "PID (comm_15_bytes_max) ..." */ + char buf[32]; /* should be enough */ + char *p, *pe; - /* if readlink fails, execbuf still contains "" */ - n = strcmp(execbuf, name); - if (ENABLE_FEATURE_CLEAN_UP) - free(execbuf); - return !n; /* nonzero (true) if execbuf == name */ + sprintf(buf, "/proc/%u/stat", (unsigned)pid); + if (open_read_close(buf, buf, sizeof(buf) - 1) < 0) + return 0; + buf[sizeof(buf) - 1] = '\0'; /* paranoia */ + p = strchr(buf, '('); + if (!p) + return 0; + pe = strrchr(++p, ')'); + if (!pe) + return 0; + *pe = '\0'; + /* we require comm to match and to not be truncated */ + /* in Linux, if comm is 15 chars, it may be a truncated + * name, so we don't allow that to match */ + if (strlen(p) >= COMM_LEN - 1) /* COMM_LEN is 16 */ + return 0; + return strcmp(p, cmdname) == 0; } -static int pid_is_user(int pid, int uid) +static int pid_is_user(int pid) { struct stat sb; char buf[sizeof("/proc/") + sizeof(int)*3]; - sprintf(buf, "/proc/%u", pid); + sprintf(buf, "/proc/%u", (unsigned)pid); if (stat(buf, &sb) != 0) return 0; - return (sb.st_uid == uid); -} - -static int pid_is_cmd(pid_t pid, const char *name) -{ - char fname[sizeof("/proc//stat") + sizeof(int)*3]; - char *buf; - int r = 0; - - sprintf(fname, "/proc/%u/stat", pid); - buf = xmalloc_open_read_close(fname, NULL); - if (buf) { - char *p = strchr(buf, '('); - if (p) { - char *pe = strrchr(++p, ')'); - if (pe) { - *pe = '\0'; - r = !strcmp(p, name); - } - } - free(buf); - } - return r; + return (sb.st_uid == (uid_t)user_id); } static void check(int pid) { struct pid_list *p; - if (execname && !pid_is_exec(pid, execname)) { + if (execname && !pid_is_exec(pid)) { return; } - if (userspec && !pid_is_user(pid, user_id)) { + if (cmdname && !pid_is_name(pid)) { return; } - if (cmdname && !pid_is_cmd(pid, cmdname)) { + if (userspec && !pid_is_user(pid)) { return; } p = xmalloc(sizeof(*p)); - p->next = found; + p->next = G.found_procs; p->pid = pid; - found = p; + G.found_procs = p; } static void do_pidfile(void) @@ -108,7 +277,7 @@ static void do_pidfile(void) FILE *f; unsigned pid; - f = fopen(pidfile, "r"); + f = fopen_for_read(pidfile); if (f) { if (fscanf(f, "%u", &pid) == 1) check(pid); @@ -121,7 +290,7 @@ static void do_procinit(void) { DIR *procdir; struct dirent *entry; - int foundany, pid; + int pid; if (pidfile) { do_pidfile(); @@ -130,16 +299,23 @@ static void do_procinit(void) procdir = xopendir("/proc"); - foundany = 0; - while ((entry = readdir(procdir)) != NULL) { + pid = 0; + while (1) { + errno = 0; /* clear any previous error */ + entry = readdir(procdir); +// TODO: this check is too generic, it's better +// to check for exact errno(s) which mean that we got stale entry + if (errno) /* Stale entry, process has died after opendir */ + continue; + if (!entry) /* EOF, no more entries */ + break; pid = bb_strtou(entry->d_name, NULL, 10); - if (errno) + if (errno) /* NaN */ continue; - foundany++; check(pid); } closedir(procdir); - if (!foundany) + if (!pid) bb_error_msg_and_die("nothing in /proc - not mounted?"); } @@ -149,40 +325,45 @@ static int do_stop(void) struct pid_list *p; int killed = 0; - do_procinit(); - if (cmdname) { if (ENABLE_FEATURE_CLEAN_UP) what = xstrdup(cmdname); if (!ENABLE_FEATURE_CLEAN_UP) what = cmdname; } else if (execname) { if (ENABLE_FEATURE_CLEAN_UP) what = xstrdup(execname); if (!ENABLE_FEATURE_CLEAN_UP) what = execname; - } else if (pidfile) + } else if (pidfile) { what = xasprintf("process in pidfile '%s'", pidfile); - else if (userspec) + } else if (userspec) { what = xasprintf("process(es) owned by '%s'", userspec); - else + } else { bb_error_msg_and_die("internal error, please report"); + } - if (!found) { - if (!quiet) + if (!G.found_procs) { + if (!QUIET) printf("no %s found; none killed\n", what); killed = -1; goto ret; } - for (p = found; p; p = p->next) { - if (kill(p->pid, signal_nr) == 0) { - p->pid = - p->pid; + for (p = G.found_procs; p; p = p->next) { + if (kill(p->pid, TEST ? 0 : signal_nr) == 0) { killed++; } else { - bb_perror_msg("warning: killing process %u", p->pid); + bb_perror_msg("warning: killing process %u", (unsigned)p->pid); + p->pid = 0; + if (TEST) { + /* Example: -K --test --pidfile PIDFILE detected + * that PIDFILE's pid doesn't exist */ + killed = -1; + goto ret; + } } } - if (!quiet && killed) { + if (!QUIET && killed) { printf("stopped %s (pid", what); - for (p = found; p; p = p->next) - if (p->pid < 0) - printf(" %u", - p->pid); + for (p = G.found_procs; p; p = p->next) + if (p->pid) + printf(" %u", (unsigned)p->pid); puts(")"); } ret: @@ -192,17 +373,18 @@ static int do_stop(void) } #if ENABLE_FEATURE_START_STOP_DAEMON_LONG_OPTIONS -static const char start_stop_daemon_longopts[] = +static const char start_stop_daemon_longopts[] ALIGN1 = "stop\0" No_argument "K" "start\0" No_argument "S" "background\0" No_argument "b" "quiet\0" No_argument "q" + "test\0" No_argument "t" "make-pidfile\0" No_argument "m" -#if ENABLE_FEATURE_START_STOP_DAEMON_FANCY +# if ENABLE_FEATURE_START_STOP_DAEMON_FANCY "oknodo\0" No_argument "o" "verbose\0" No_argument "v" "nicelevel\0" Required_argument "N" -#endif +# endif "startas\0" Required_argument "a" "name\0" Required_argument "n" "signal\0" Required_argument "s" @@ -210,58 +392,53 @@ static const char start_stop_daemon_longopts[] = "chuid\0" Required_argument "c" "exec\0" Required_argument "x" "pidfile\0" Required_argument "p" -#if ENABLE_FEATURE_START_STOP_DAEMON_FANCY +# if ENABLE_FEATURE_START_STOP_DAEMON_FANCY "retry\0" Required_argument "R" -#endif +# endif ; +# define GETOPT32 getopt32long +# define LONGOPTS start_stop_daemon_longopts, +#else +# define GETOPT32 getopt32 +# define LONGOPTS #endif -enum { - CTX_STOP = 0x1, - CTX_START = 0x2, - OPT_BACKGROUND = 0x4, // -b - OPT_QUIET = 0x8, // -q - OPT_MAKEPID = 0x10, // -m - OPT_a = 0x20, // -a - OPT_n = 0x40, // -n - OPT_s = 0x80, // -s - OPT_u = 0x100, // -u - OPT_c = 0x200, // -c - OPT_x = 0x400, // -x - OPT_p = 0x800, // -p - OPT_OKNODO = 0x1000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -o - OPT_VERBOSE = 0x2000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -v - OPT_NICELEVEL = 0x4000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -N -}; - -int start_stop_daemon_main(int argc, char **argv); -int start_stop_daemon_main(int argc, char **argv) +int start_stop_daemon_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv) { unsigned opt; char *signame; char *startas; char *chuid; +#ifdef OLDER_VERSION_OF_X + struct stat execstat; +#endif #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY // char *retry_arg = NULL; // int retries = -1; char *opt_N; #endif -#if ENABLE_FEATURE_START_STOP_DAEMON_LONG_OPTIONS - applet_long_options = start_stop_daemon_longopts; -#endif - /* Check required one context option was given */ - opt_complementary = "K:S:K--S:S--K:m?p:K?xpun:S?xa"; - opt = getopt32(argc, argv, "KSbqma:n:s:u:c:x:p:" - USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:"), -// USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:"), + INIT_G(); + + opt = GETOPT32(argv, "^" + "KSbqtma:n:s:u:c:x:p:" + IF_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:") + /* -K or -S is required; they are mutually exclusive */ + /* -p is required if -m is given */ + /* -xpun (at least one) is required if -K is given */ + /* -xa (at least one) is required if -S is given */ + /* -q turns off -v */ + "\0" + "K:S:K--S:S--K:m?p:K?xpun:S?xa" + IF_FEATURE_START_STOP_DAEMON_FANCY("q-v"), + LONGOPTS &startas, &cmdname, &signame, &userspec, &chuid, &execname, &pidfile - USE_FEATURE_START_STOP_DAEMON_FANCY(,&opt_N) -// USE_FEATURE_START_STOP_DAEMON_FANCY(,&retry_arg) + IF_FEATURE_START_STOP_DAEMON_FANCY(,&opt_N) + /* We accept and ignore -R / --retry */ + IF_FEATURE_START_STOP_DAEMON_FANCY(,NULL) ); - quiet = (opt & OPT_QUIET) && !(opt & OPT_VERBOSE); - if (opt & OPT_s) { signal_nr = get_signum(signame); if (signal_nr < 0) bb_show_usage(); @@ -269,12 +446,18 @@ int start_stop_daemon_main(int argc, char **argv) if (!(opt & OPT_a)) startas = execname; + if (!execname) /* in case -a is given and -x is not */ + execname = startas; + if (execname) { + G.execname_sizeof = strlen(execname) + 1; + G.execname_cmpbuf = xmalloc(G.execname_sizeof + 1); + } -// USE_FEATURE_START_STOP_DAEMON_FANCY( +// IF_FEATURE_START_STOP_DAEMON_FANCY( // if (retry_arg) -// retries = xatoi_u(retry_arg); +// retries = xatoi_positive(retry_arg); // ) - argc -= optind; + //argc -= optind; argv += optind; if (userspec) { @@ -282,53 +465,67 @@ int start_stop_daemon_main(int argc, char **argv) if (errno) user_id = xuname2uid(userspec); } + /* Both start and stop need to know current processes */ + do_procinit(); if (opt & CTX_STOP) { int i = do_stop(); return (opt & OPT_OKNODO) ? 0 : (i <= 0); } - do_procinit(); - - if (found) { - if (!quiet) - printf("%s already running\n%d\n", execname, found->pid); + if (G.found_procs) { + if (!QUIET) + printf("%s is already running\n%u\n", execname, (unsigned)G.found_procs->pid); return !(opt & OPT_OKNODO); } + +#ifdef OLDER_VERSION_OF_X + if (execname) + xstat(execname, &execstat); +#endif + *--argv = startas; if (opt & OPT_BACKGROUND) { #if BB_MMU - bb_daemonize(0); + bb_daemonize(DAEMON_DEVNULL_STDIO + DAEMON_CLOSE_EXTRA_FDS + DAEMON_DOUBLE_FORK); + /* DAEMON_DEVNULL_STDIO is superfluous - + * it's always done by bb_daemonize() */ #else - pid_t pid = vfork(); - if (pid < 0) /* error */ - bb_perror_msg_and_die("vfork"); + /* Daemons usually call bb_daemonize_or_rexec(), but SSD can do + * without: SSD is not itself a daemon, it _execs_ a daemon. + * The usual NOMMU problem of "child can't run indefinitely, + * it must exec" does not bite us: we exec anyway. + */ + pid_t pid = xvfork(); if (pid != 0) { /* parent */ /* why _exit? the child may have changed the stack, * so "return 0" may do bad things */ - _exit(0); + _exit(EXIT_SUCCESS); } - /* child */ + /* Child */ setsid(); /* detach from controlling tty */ - /* Redirect stdio to /dev/null, close extra FDs. - * We do not actually daemonize because of DAEMON_ONLY_SANITIZE */ - bb_daemonize_or_rexec( - DAEMON_DEVNULL_STDIO - + DAEMON_CLOSE_EXTRA_FDS - + DAEMON_ONLY_SANITIZE, - NULL /* argv, unused */ ); + /* Redirect stdio to /dev/null, close extra FDs */ + bb_daemon_helper(DAEMON_DEVNULL_STDIO + DAEMON_CLOSE_EXTRA_FDS); #endif } if (opt & OPT_MAKEPID) { - /* user wants _us_ to make the pidfile */ + /* User wants _us_ to make the pidfile */ write_pidfile(pidfile); } if (opt & OPT_c) { struct bb_uidgid_t ugid; parse_chown_usergroup_or_die(&ugid, chuid); - if (ugid.gid != (gid_t) -1) xsetgid(ugid.gid); - if (ugid.uid != (uid_t) -1) xsetuid(ugid.uid); + if (ugid.uid != (uid_t) -1L) { + struct passwd *pw = xgetpwuid(ugid.uid); + if (ugid.gid != (gid_t) -1L) + pw->pw_gid = ugid.gid; + /* initgroups, setgid, setuid: */ + change_identity(pw); + } else if (ugid.gid != (gid_t) -1L) { + xsetgid(ugid.gid); + setgroups(1, &ugid.gid); + } } #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY if (opt & OPT_NICELEVEL) { @@ -339,6 +536,6 @@ int start_stop_daemon_main(int argc, char **argv) } } #endif - execv(startas, argv); - bb_perror_msg_and_die("cannot start %s", startas); + execvp(startas, argv); + bb_perror_msg_and_die("can't execute '%s'", startas); }