/* * uuidd.c --- UUID-generation daemon * * Copyright (C) 2007 Theodore Ts'o * * %Begin-Header% * This file may be redistributed under the terms of the GNU Public * License. * %End-Header% */ /* * The uuidd protocol. * * Client: * | operation type (1 byte) | number of uuids (if bulk request, 4 bytes) | * * Server: * | reply length (4 bytes) | uuid reply (16 bytes) | * or * | reply length (4 bytes) | uuid reply (16 bytes) multiply by number when random bulk request | * or * | reply length (4 bytes) | uuid reply (16 bytes) | number (4 bytes) time bulk | * or * | reply length (4 bytes) | pid or maxop number string length in ascii (up to 7 bytes) | */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "uuid.h" #include "uuidd.h" #include "all-io.h" #include "c.h" #include "closestream.h" #include "strutils.h" #include "optutils.h" #include "monotonic.h" #include "timer.h" #ifdef HAVE_LIBSYSTEMD # include #endif #include "nls.h" /* Protocol segment lengths */ typedef uint8_t uuidd_prot_op_t; /* client operation field */ typedef int32_t uuidd_prot_num_t; /* number of requested uuids */ enum { /* client - server buffer size */ UUIDD_PROT_BUFSZ = ((sizeof(uuidd_prot_num_t)) + (sizeof(uuid_t) * 63)) }; /* server loop control structure */ struct uuidd_cxt_t { const char *cleanup_pidfile; const char *cleanup_socket; uint32_t timeout; unsigned int debug: 1, quiet: 1, no_fork: 1, no_sock: 1; }; struct uuidd_options_t { const char *pidfile_path; const char *socket_path; uuidd_prot_num_t num; uuidd_prot_op_t do_type; unsigned int do_kill:1, no_pid:1, s_flag:1; }; static void __attribute__((__noreturn__)) usage(void) { FILE *out = stdout; fputs(USAGE_HEADER, out); fprintf(out, _(" %s [options]\n"), program_invocation_short_name); fputs(USAGE_SEPARATOR, out); fputs(_("A daemon for generating UUIDs.\n"), out); fputs(USAGE_OPTIONS, out); fputs(_(" -p, --pid path to pid file\n"), out); fputs(_(" -s, --socket path to socket\n"), out); fputs(_(" -T, --timeout specify inactivity timeout\n"), out); fputs(_(" -k, --kill kill running daemon\n"), out); fputs(_(" -r, --random test random-based generation\n"), out); fputs(_(" -t, --time test time-based generation\n"), out); fputs(_(" -n, --uuids request number of uuids\n"), out); fputs(_(" -P, --no-pid do not create pid file\n"), out); fputs(_(" -F, --no-fork do not daemonize using double-fork\n"), out); fputs(_(" -S, --socket-activation do not create listening socket\n"), out); fputs(_(" -d, --debug run in debugging mode\n"), out); fputs(_(" -q, --quiet turn on quiet mode\n"), out); fputs(USAGE_SEPARATOR, out); printf(USAGE_HELP_OPTIONS(25)); printf(USAGE_MAN_TAIL("uuidd(8)")); exit(EXIT_SUCCESS); } static void create_daemon(void) { uid_t euid; if (daemon(0, 0)) err(EXIT_FAILURE, "daemon"); euid = geteuid(); if (setreuid(euid, euid) < 0) err(EXIT_FAILURE, "setreuid"); } static int call_daemon(const char *socket_path, uuidd_prot_op_t op, char *buf, size_t buflen, uuidd_prot_num_t *num, const char **err_context) { char op_buf[sizeof(op) + sizeof(*num)]; size_t op_len; int s; ssize_t ret; int32_t reply_len = 0; struct sockaddr_un srv_addr; if (((op == UUIDD_OP_BULK_TIME_UUID) || (op == UUIDD_OP_BULK_RANDOM_UUID)) && !num) { if (err_context) *err_context = _("bad arguments"); errno = EINVAL; return -1; } if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { if (err_context) *err_context = _("socket"); return -1; } srv_addr.sun_family = AF_UNIX; assert(strlen(socket_path) < sizeof(srv_addr.sun_path)); xstrncpy(srv_addr.sun_path, socket_path, sizeof(srv_addr.sun_path)); if (connect(s, (const struct sockaddr *) &srv_addr, sizeof(struct sockaddr_un)) < 0) { if (err_context) *err_context = _("connect"); close(s); return -1; } if (op == UUIDD_OP_BULK_RANDOM_UUID) { if ((buflen - sizeof(*num)) < (size_t)((*num) * sizeof(uuid_t))) *num = (buflen - sizeof(*num)) / sizeof(uuid_t); } op_buf[0] = op; op_len = sizeof(op); if ((op == UUIDD_OP_BULK_TIME_UUID) || (op == UUIDD_OP_BULK_RANDOM_UUID)) { memcpy(op_buf + sizeof(op), num, sizeof(*num)); op_len += sizeof(*num); } ret = write_all(s, op_buf, op_len); if (ret < 0) { if (err_context) *err_context = _("write"); close(s); return -1; } ret = read_all(s, (char *) &reply_len, sizeof(reply_len)); if (ret < 0) { if (err_context) *err_context = _("read count"); close(s); return -1; } if (reply_len < 0 || (size_t) reply_len > buflen) { if (err_context) *err_context = _("bad response length"); close(s); return -1; } ret = read_all(s, (char *) buf, reply_len); if ((ret > 0) && (op == UUIDD_OP_BULK_TIME_UUID)) { if ((sizeof(uuid_t) + sizeof(*num)) <= (size_t) reply_len) memcpy(buf + sizeof(uuid_t), num, sizeof(*num)); else *num = -1; } if ((ret > 0) && (op == UUIDD_OP_BULK_RANDOM_UUID)) { if (sizeof(*num) <= (size_t) reply_len) memcpy(buf, num, sizeof(*num)); else *num = -1; } close(s); return ret; } /* * Exclusively create and open a pid file with path @pidfile_path * * Return file descriptor of the created pid_file. */ static int create_pidfile(struct uuidd_cxt_t *cxt, const char *pidfile_path) { int fd_pidfile; struct flock fl; fd_pidfile = open(pidfile_path, O_CREAT | O_RDWR, 0664); if (fd_pidfile < 0) { if (!cxt->quiet) warn(_("cannot open %s"), pidfile_path); exit(EXIT_FAILURE); } cxt->cleanup_pidfile = pidfile_path; fl.l_type = F_WRLCK; fl.l_whence = SEEK_SET; fl.l_start = 0; fl.l_len = 0; fl.l_pid = 0; while (fcntl(fd_pidfile, F_SETLKW, &fl) < 0) { if ((errno == EAGAIN) || (errno == EINTR)) continue; if (!cxt->quiet) warn(_("cannot lock %s"), pidfile_path); exit(EXIT_FAILURE); } return fd_pidfile; } /* * Create AF_UNIX, SOCK_STREAM socket and bind to @socket_path * * If @will_fork is true, then make sure the descriptor * of the socket is >2, so that it won't be later closed * during create_daemon(). * * Return file descriptor corresponding to created socket. */ static int create_socket(struct uuidd_cxt_t *uuidd_cxt, const char *socket_path, int will_fork) { struct sockaddr_un my_addr; mode_t save_umask; int s; if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { if (!uuidd_cxt->quiet) warn(_("couldn't create unix stream socket")); exit(EXIT_FAILURE); } /* * Make sure the socket isn't using fd numbers 0-2 to avoid it * getting closed by create_daemon() */ while (will_fork && s <= 2) { s = dup(s); if (s < 0) err(EXIT_FAILURE, "dup"); } /* * Create the address we will be binding to. */ my_addr.sun_family = AF_UNIX; assert(strlen(socket_path) < sizeof(my_addr.sun_path)); xstrncpy(my_addr.sun_path, socket_path, sizeof(my_addr.sun_path)); unlink(socket_path); save_umask = umask(0); if (bind(s, (const struct sockaddr *) &my_addr, sizeof(struct sockaddr_un)) < 0) { if (!uuidd_cxt->quiet) warn(_("couldn't bind unix socket %s"), socket_path); exit(EXIT_FAILURE); } umask(save_umask); uuidd_cxt->cleanup_socket = socket_path; return s; } static void __attribute__((__noreturn__)) all_done(const struct uuidd_cxt_t *uuidd_cxt, int ret) { if (uuidd_cxt->cleanup_pidfile) unlink(uuidd_cxt->cleanup_pidfile); if (uuidd_cxt->cleanup_socket) unlink(uuidd_cxt->cleanup_socket); exit(ret); } static void handle_signal(const struct uuidd_cxt_t *uuidd_cxt, int fd) { struct signalfd_siginfo info; ssize_t bytes; bytes = read(fd, &info, sizeof(info)); if (bytes != sizeof(info)) { if (errno == EAGAIN) return; warn(_("receiving signal failed")); info.ssi_signo = 0; } if (info.ssi_signo == SIGPIPE) return; /* ignored */ all_done(uuidd_cxt, EXIT_SUCCESS); } static void timeout_handler(int sig __attribute__((__unused__)), siginfo_t * info, void *context __attribute__((__unused__))) { #ifdef HAVE_TIMER_CREATE if (info->si_code == SI_TIMER) #endif errx(EXIT_FAILURE, _("timed out")); } static void server_loop(const char *socket_path, const char *pidfile_path, struct uuidd_cxt_t *uuidd_cxt) { struct sockaddr_un from_addr; socklen_t fromlen; int32_t reply_len = 0; uuid_t uu; char reply_buf[UUIDD_PROT_BUFSZ], *cp; uuidd_prot_op_t op; char str[UUID_STR_LEN]; int i, ns, len; uuidd_prot_num_t num; /* intentionally uninitialized */ int s = 0; int fd_pidfile = -1; int ret; struct pollfd pfd[2]; sigset_t sigmask; int sigfd; enum { POLLFD_SIGNAL = 0, POLLFD_SOCKET }; #ifdef HAVE_LIBSYSTEMD if (!uuidd_cxt->no_sock) /* no_sock implies no_fork and no_pid */ #endif { struct ul_timer timer; struct itimerval timeout; memset(&timeout, 0, sizeof timeout); timeout.it_value.tv_sec = 30; if (setup_timer(&timer, &timeout, &timeout_handler)) err(EXIT_FAILURE, _("cannot set up timer")); if (pidfile_path) fd_pidfile = create_pidfile(uuidd_cxt, pidfile_path); ret = call_daemon(socket_path, UUIDD_OP_GETPID, reply_buf, sizeof(reply_buf), 0, NULL); cancel_timer(&timer); if (ret > 0) { if (!uuidd_cxt->quiet) warnx(_("uuidd daemon is already running at pid %s"), reply_buf); exit(EXIT_FAILURE); } s = create_socket(uuidd_cxt, socket_path, (!uuidd_cxt->debug || !uuidd_cxt->no_fork)); if (listen(s, SOMAXCONN) < 0) { if (!uuidd_cxt->quiet) warn(_("couldn't listen on unix socket %s"), socket_path); exit(EXIT_FAILURE); } if (!uuidd_cxt->debug && !uuidd_cxt->no_fork) create_daemon(); if (pidfile_path) { snprintf(reply_buf, sizeof(reply_buf), "%8d\n", getpid()); if (ftruncate(fd_pidfile, 0)) err(EXIT_FAILURE, _("could not truncate file: %s"), pidfile_path); write_all(fd_pidfile, reply_buf, strlen(reply_buf)); if (fd_pidfile > 1 && close_fd(fd_pidfile) != 0) err(EXIT_FAILURE, _("write failed: %s"), pidfile_path); } } #ifdef HAVE_LIBSYSTEMD if (uuidd_cxt->no_sock) { const int r = sd_listen_fds(0); if (r < 0) { errno = r * -1; err(EXIT_FAILURE, _("sd_listen_fds() failed")); } else if (r == 0) errx(EXIT_FAILURE, _("no file descriptors received, check systemctl status uuidd.socket")); else if (1 < r) errx(EXIT_FAILURE, _("too many file descriptors received, check uuidd.socket")); s = SD_LISTEN_FDS_START + 0; } #endif sigemptyset(&sigmask); sigaddset(&sigmask, SIGHUP); sigaddset(&sigmask, SIGINT); sigaddset(&sigmask, SIGTERM); sigaddset(&sigmask, SIGALRM); sigaddset(&sigmask, SIGPIPE); /* Block signals so that they aren't handled according to their * default dispositions */ sigprocmask(SIG_BLOCK, &sigmask, NULL); if ((sigfd = signalfd(-1, &sigmask, 0)) < 0) err(EXIT_FAILURE, _("cannot set signal handler")); pfd[POLLFD_SIGNAL].fd = sigfd; pfd[POLLFD_SOCKET].fd = s; pfd[POLLFD_SIGNAL].events = pfd[POLLFD_SOCKET].events = POLLIN | POLLERR | POLLHUP; while (1) { ret = poll(pfd, ARRAY_SIZE(pfd), uuidd_cxt->timeout ? (int) uuidd_cxt->timeout * 1000 : -1); if (ret < 0) { if (errno == EAGAIN) continue; warn(_("poll failed")); all_done(uuidd_cxt, EXIT_FAILURE); } if (ret == 0) { /* true when poll() times out */ if (uuidd_cxt->debug) fprintf(stderr, _("timeout [%d sec]\n"), uuidd_cxt->timeout); all_done(uuidd_cxt, EXIT_SUCCESS); } if (pfd[POLLFD_SIGNAL].revents != 0) handle_signal(uuidd_cxt, sigfd); if (pfd[POLLFD_SOCKET].revents == 0) continue; fromlen = sizeof(from_addr); ns = accept(s, (struct sockaddr *) &from_addr, &fromlen); if (ns < 0) { if ((errno == EAGAIN) || (errno == EINTR)) continue; err(EXIT_FAILURE, "accept"); } len = read(ns, &op, sizeof(op)); if (len != sizeof(op)) { if (len < 0) warn(_("read failed")); else warnx(_("error reading from client, len = %d"), len); goto shutdown_socket; } if ((op == UUIDD_OP_BULK_TIME_UUID) || (op == UUIDD_OP_BULK_RANDOM_UUID)) { if (read_all(ns, (char *) &num, sizeof(num)) != sizeof(num)) goto shutdown_socket; if (uuidd_cxt->debug) fprintf(stderr, _("operation %d, incoming num = %d\n"), op, num); } else if (uuidd_cxt->debug) fprintf(stderr, _("operation %d\n"), op); switch (op) { case UUIDD_OP_GETPID: snprintf(reply_buf, sizeof(reply_buf), "%d", getpid()); reply_len = strlen(reply_buf) + 1; break; case UUIDD_OP_GET_MAXOP: snprintf(reply_buf, sizeof(reply_buf), "%d", UUIDD_MAX_OP); reply_len = strlen(reply_buf) + 1; break; case UUIDD_OP_TIME_UUID: num = 1; if (__uuid_generate_time(uu, &num) < 0 && !uuidd_cxt->quiet) warnx(_("failed to open/lock clock counter")); if (uuidd_cxt->debug) { uuid_unparse(uu, str); fprintf(stderr, _("Generated time UUID: %s\n"), str); } memcpy(reply_buf, uu, sizeof(uu)); reply_len = sizeof(uu); break; case UUIDD_OP_RANDOM_UUID: num = 1; if (__uuid_generate_time(uu, &num) < 0 && !uuidd_cxt->quiet) warnx(_("failed to open/lock clock counter")); if (uuidd_cxt->debug) { uuid_unparse(uu, str); fprintf(stderr, _("Generated random UUID: %s\n"), str); } memcpy(reply_buf, uu, sizeof(uu)); reply_len = sizeof(uu); break; case UUIDD_OP_BULK_TIME_UUID: if (__uuid_generate_time(uu, &num) < 0 && !uuidd_cxt->quiet) warnx(_("failed to open/lock clock counter")); if (uuidd_cxt->debug) { uuid_unparse(uu, str); fprintf(stderr, P_("Generated time UUID %s " "and %d following\n", "Generated time UUID %s " "and %d following\n", num - 1), str, num - 1); } memcpy(reply_buf, uu, sizeof(uu)); reply_len = sizeof(uu); memcpy(reply_buf + reply_len, &num, sizeof(num)); reply_len += sizeof(num); break; case UUIDD_OP_BULK_RANDOM_UUID: if (num < 0) num = 1; if ((sizeof(reply_buf) - sizeof(num)) < (size_t) (sizeof(uu) * num)) num = (sizeof(reply_buf) - sizeof(num)) / sizeof(uu); __uuid_generate_random((unsigned char *) reply_buf + sizeof(num), &num); reply_len = sizeof(num) + (sizeof(uu) * num); memcpy(reply_buf, &num, sizeof(num)); if (uuidd_cxt->debug) { fprintf(stderr, P_("Generated %d UUID:\n", "Generated %d UUIDs:\n", num), num); cp = reply_buf + sizeof(num); for (i = 0; i < num; i++) { uuid_unparse((unsigned char *)cp, str); fprintf(stderr, "\t%s\n", str); cp += sizeof(uu); } } break; default: if (uuidd_cxt->debug) fprintf(stderr, _("Invalid operation %d\n"), op); goto shutdown_socket; } write_all(ns, (char *) &reply_len, sizeof(num)); write_all(ns, reply_buf, reply_len); shutdown_socket: close(ns); } } static void __attribute__ ((__noreturn__)) unexpected_size(int size) { errx(EXIT_FAILURE, _("Unexpected reply length from server %d"), size); } static void parse_options(int argc, char **argv, struct uuidd_cxt_t *uuidd_cxt, struct uuidd_options_t *uuidd_opts) { const struct option longopts[] = { {"pid", required_argument, NULL, 'p'}, {"socket", required_argument, NULL, 's'}, {"timeout", required_argument, NULL, 'T'}, {"kill", no_argument, NULL, 'k'}, {"random", no_argument, NULL, 'r'}, {"time", no_argument, NULL, 't'}, {"uuids", required_argument, NULL, 'n'}, {"no-pid", no_argument, NULL, 'P'}, {"no-fork", no_argument, NULL, 'F'}, {"socket-activation", no_argument, NULL, 'S'}, {"debug", no_argument, NULL, 'd'}, {"quiet", no_argument, NULL, 'q'}, {"version", no_argument, NULL, 'V'}, {"help", no_argument, NULL, 'h'}, {NULL, 0, NULL, 0} }; const ul_excl_t excl[] = { { 'P', 'p' }, { 'd', 'q' }, { 'r', 't' }, { 0 } }; int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT; int c; while ((c = getopt_long(argc, argv, "p:s:T:krtn:PFSdqVh", longopts, NULL)) != -1) { err_exclusive_options(c, longopts, excl, excl_st); switch (c) { case 'd': uuidd_cxt->debug = 1; break; case 'k': uuidd_opts->do_kill = 1; break; case 'n': uuidd_opts->num = (uuidd_prot_num_t) strtou16_or_err(optarg, _("failed to parse --uuids")); break; case 'p': uuidd_opts->pidfile_path = optarg; break; case 'P': uuidd_opts->no_pid = 1; break; case 'F': uuidd_cxt->no_fork = 1; break; case 'S': #ifdef HAVE_LIBSYSTEMD uuidd_cxt->no_sock = 1; uuidd_cxt->no_fork = 1; uuidd_opts->no_pid = 1; #else errx(EXIT_FAILURE, _("uuidd has been built without " "support for socket activation")); #endif break; case 'q': uuidd_cxt->quiet = 1; break; case 'r': uuidd_opts->do_type = UUIDD_OP_RANDOM_UUID; break; case 's': uuidd_opts->socket_path = optarg; uuidd_opts->s_flag = 1; break; case 't': uuidd_opts->do_type = UUIDD_OP_TIME_UUID; break; case 'T': uuidd_cxt->timeout = strtou32_or_err(optarg, _("failed to parse --timeout")); break; case 'V': print_version(EXIT_SUCCESS); case 'h': usage(); default: errtryhelp(EXIT_FAILURE); } } if (0 < uuidd_opts->num) { switch (uuidd_opts->do_type) { case UUIDD_OP_RANDOM_UUID: uuidd_opts->do_type = UUIDD_OP_BULK_RANDOM_UUID; break; case UUIDD_OP_TIME_UUID: uuidd_opts->do_type = UUIDD_OP_BULK_TIME_UUID; break; } } } int main(int argc, char **argv) { const char *err_context = NULL; char *cp; int ret; struct uuidd_cxt_t uuidd_cxt = { .timeout = 0 }; struct uuidd_options_t uuidd_opts = { .socket_path = UUIDD_SOCKET_PATH }; setlocale(LC_ALL, ""); bindtextdomain(PACKAGE, LOCALEDIR); textdomain(PACKAGE); close_stdout_atexit(); parse_options(argc, argv, &uuidd_cxt, &uuidd_opts); if (strlen(uuidd_opts.socket_path) >= sizeof(((struct sockaddr_un *)0)->sun_path)) errx(EXIT_FAILURE, _("socket name too long: %s"), uuidd_opts.socket_path); if (!uuidd_opts.no_pid && !uuidd_opts.pidfile_path) uuidd_opts.pidfile_path = UUIDD_PIDFILE_PATH; /* custom socket path and socket-activation make no sense */ if (uuidd_opts.s_flag && uuidd_cxt.no_sock && !uuidd_cxt.quiet) warnx(_("Both --socket-activation and --socket specified. " "Ignoring --socket.")); if (uuidd_opts.num && uuidd_opts.do_type) { char buf[UUIDD_PROT_BUFSZ]; char str[UUID_STR_LEN]; ret = call_daemon(uuidd_opts.socket_path, uuidd_opts.do_type, buf, sizeof(buf), &uuidd_opts.num, &err_context); if (ret < 0) err(EXIT_FAILURE, _("error calling uuidd daemon (%s)"), err_context ? : _("unexpected error")); if (uuidd_opts.do_type == UUIDD_OP_BULK_TIME_UUID) { if (ret != sizeof(uuid_t) + sizeof(uuidd_opts.num)) unexpected_size(ret); uuid_unparse((unsigned char *) buf, str); printf(P_("%s and %d subsequent UUID\n", "%s and %d subsequent UUIDs\n", uuidd_opts.num - 1), str, uuidd_opts.num - 1); } else { int i; printf(_("List of UUIDs:\n")); cp = buf + sizeof(uuidd_opts.num); if (ret != (int) (sizeof(uuidd_opts.num) + uuidd_opts.num * sizeof(uuid_t))) unexpected_size(ret); for (i = 0; i < uuidd_opts.num; i++, cp += sizeof(uuid_t)) { uuid_unparse((unsigned char *) cp, str); printf("\t%s\n", str); } } return EXIT_SUCCESS; } if (uuidd_opts.do_type) { uuid_t uu; char str[UUID_STR_LEN]; ret = call_daemon(uuidd_opts.socket_path, uuidd_opts.do_type, (char *) &uu, sizeof(uu), 0, &err_context); if (ret < 0) err(EXIT_FAILURE, _("error calling uuidd daemon (%s)"), err_context ? : _("unexpected error")); if (ret != sizeof(uu)) unexpected_size(ret); uuid_unparse(uu, str); printf("%s\n", str); return EXIT_SUCCESS; } if (uuidd_opts.do_kill) { char buf[16]; ret = call_daemon(uuidd_opts.socket_path, UUIDD_OP_GETPID, buf, sizeof(buf), 0, NULL); if (0 < ret) { pid_t pid; pid = (pid_t)strtou32_or_err(buf, _("failed to parse pid")); ret = kill(pid, SIGTERM); if (ret < 0) { if (!uuidd_cxt.quiet) warn(_("couldn't kill uuidd running " "at pid %d"), pid); return EXIT_FAILURE; } if (!uuidd_cxt.quiet) printf(_("Killed uuidd running at pid %d.\n"), pid); } return EXIT_SUCCESS; } server_loop(uuidd_opts.socket_path, uuidd_opts.pidfile_path, &uuidd_cxt); return EXIT_SUCCESS; }