diff options
Diffstat (limited to 'src/main.c')
| -rw-r--r-- | src/main.c | 920 |
1 files changed, 920 insertions, 0 deletions
diff --git a/src/main.c b/src/main.c new file mode 100644 index 0000000..8702a4b --- /dev/null +++ b/src/main.c @@ -0,0 +1,920 @@ +/* + * main.c + * + * Copyright (C) 2009-2021 Nikias Bassen <nikias@gmx.li> + * Copyright (C) 2013-2014 Martin Szulecki <m.szulecki@libimobiledevice.org> + * Copyright (C) 2009 Hector Martin <hector@marcansoft.com> + * Copyright (C) 2009 Paul Sladen <libiphone@paul.sladen.org> + * + * 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 + * the Free Software Foundation, either version 2 or version 3. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#define _DEFAULT_SOURCE +#define _BSD_SOURCE +#define _GNU_SOURCE + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <errno.h> +#include <string.h> +#include <stdlib.h> +#include <signal.h> +#include <unistd.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <netinet/in.h> +#include <netdb.h> +#include <arpa/inet.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <sys/resource.h> +#include <fcntl.h> +#include <getopt.h> +#include <pwd.h> +#include <grp.h> + +#include "log.h" +#include "usb.h" +#include "device.h" +#include "client.h" +#include "conf.h" + +static const char *socket_path = "/var/run/usbmuxd"; +#define DEFAULT_LOCKFILE "/var/run/usbmuxd.pid" +static const char *lockfile = DEFAULT_LOCKFILE; + +// Global state used in other files +int should_exit; +int should_discover; +int use_logfile = 0; +int no_preflight = 0; + +// Global state for main.c +static int verbose = 0; +static int foreground = 0; +static int drop_privileges = 0; +static const char *drop_user = NULL; +static int opt_disable_hotplug = 0; +static int opt_enable_exit = 0; +static int opt_exit = 0; +static int exit_signal = 0; +static int daemon_pipe; +static const char *listen_addr = NULL; + +static int report_to_parent = 0; + +static int create_socket(void) +{ + int listenfd; + const char* socket_addr = socket_path; + const char* tcp_port; + char listen_addr_str[256]; + + if (listen_addr) { + socket_addr = listen_addr; + } + tcp_port = strrchr(socket_addr, ':'); + if (tcp_port) { + tcp_port++; + size_t nlen = tcp_port - socket_addr; + char* hostname = malloc(nlen); + struct addrinfo hints; + struct addrinfo *result, *rp; + int yes = 1; + int res; + + strncpy(hostname, socket_addr, nlen-1); + hostname[nlen-1] = '\0'; + + memset(&hints, '\0', sizeof(struct addrinfo)); + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + hints.ai_flags = AI_PASSIVE | AI_NUMERICSERV; + hints.ai_protocol = IPPROTO_TCP; + + res = getaddrinfo(hostname, tcp_port, &hints, &result); + free(hostname); + if (res != 0) { + usbmuxd_log(LL_FATAL, "%s: getaddrinfo() failed: %s\n", __func__, gai_strerror(res)); + return -1; + } + + for (rp = result; rp != NULL; rp = rp->ai_next) { + listenfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol); + if (listenfd == -1) { + listenfd = -1; + continue; + } + + if (setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (void*)&yes, sizeof(int)) == -1) { + usbmuxd_log(LL_ERROR, "%s: setsockopt(): %s", __func__, strerror(errno)); + close(listenfd); + listenfd = -1; + continue; + } + +#ifdef SO_NOSIGPIPE + if (setsockopt(listenfd, SOL_SOCKET, SO_NOSIGPIPE, (void*)&yes, sizeof(int)) == -1) { + usbmuxd_log(LL_ERROR, "%s: setsockopt(): %s", __func__, strerror(errno)); + close(listenfd); + listenfd = -1; + continue; + } +#endif + +#if defined(AF_INET6) && defined(IPV6_V6ONLY) + if (rp->ai_family == AF_INET6) { + if (setsockopt(listenfd, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&yes, sizeof(int)) == -1) { + usbmuxd_log(LL_ERROR, "%s: setsockopt() IPV6_V6ONLY: %s", __func__, strerror(errno)); + } + } +#endif + + if (bind(listenfd, rp->ai_addr, rp->ai_addrlen) < 0) { + usbmuxd_log(LL_FATAL, "%s: bind() failed: %s", __func__, strerror(errno)); + close(listenfd); + listenfd = -1; + continue; + } + + const void *addrdata = NULL; + if (rp->ai_family == AF_INET) { + addrdata = &((struct sockaddr_in*)rp->ai_addr)->sin_addr; + } +#ifdef AF_INET6 + else if (rp->ai_family == AF_INET6) { + addrdata = &((struct sockaddr_in6*)rp->ai_addr)->sin6_addr; + } +#endif + if (addrdata) { + char* endp = NULL; + uint16_t listen_port = 0; + if (rp->ai_family == AF_INET) { + listen_port = ntohs(((struct sockaddr_in*)rp->ai_addr)->sin_port); + if (inet_ntop(AF_INET, addrdata, listen_addr_str, sizeof(listen_addr_str)-6)) { + endp = &listen_addr_str[0] + strlen(listen_addr_str); + } + } +#ifdef AF_INET6 + else if (rp->ai_family == AF_INET6) { + listen_port = ntohs(((struct sockaddr_in6*)rp->ai_addr)->sin6_port); + listen_addr_str[0] = '['; + if (inet_ntop(AF_INET6, addrdata, listen_addr_str+1, sizeof(listen_addr_str)-8)) { + endp = &listen_addr_str[0] + strlen(listen_addr_str); + } + if (endp) { + *endp = ']'; + endp++; + } + } +#endif + if (endp) { + sprintf(endp, ":%u", listen_port); + } + } + break; + } + freeaddrinfo(result); + if (listenfd == -1) { + usbmuxd_log(LL_FATAL, "%s: Failed to create listening socket", __func__); + return -1; + } + } else { + struct sockaddr_un bind_addr; + + if (strcmp(socket_addr, socket_path) != 0) { + struct stat fst; + if (stat(socket_addr, &fst) == 0) { + if (!S_ISSOCK(fst.st_mode)) { + usbmuxd_log(LL_FATAL, "FATAL: File '%s' already exists and is not a socket file. Refusing to continue.", socket_addr); + return -1; + } + } + } + + if (unlink(socket_addr) == -1 && errno != ENOENT) { + usbmuxd_log(LL_FATAL, "%s: unlink(%s) failed: %s", __func__, socket_addr, strerror(errno)); + return -1; + } + + listenfd = socket(AF_UNIX, SOCK_STREAM, 0); + if (listenfd == -1) { + usbmuxd_log(LL_FATAL, "socket() failed: %s", strerror(errno)); + return -1; + } + + bzero(&bind_addr, sizeof(bind_addr)); + bind_addr.sun_family = AF_UNIX; + strncpy(bind_addr.sun_path, socket_addr, sizeof(bind_addr.sun_path)); + bind_addr.sun_path[sizeof(bind_addr.sun_path) - 1] = '\0'; + + if (bind(listenfd, (struct sockaddr*)&bind_addr, sizeof(bind_addr)) != 0) { + usbmuxd_log(LL_FATAL, "bind() failed: %s", strerror(errno)); + return -1; + } + chmod(socket_addr, 0666); + + snprintf(listen_addr_str, sizeof(listen_addr_str), "%s", socket_addr); + } + + int flags = fcntl(listenfd, F_GETFL, 0); + if (flags < 0) { + usbmuxd_log(LL_FATAL, "ERROR: Could not get flags for socket"); + } else { + if (fcntl(listenfd, F_SETFL, flags | O_NONBLOCK) < 0) { + usbmuxd_log(LL_FATAL, "ERROR: Could not set socket to non-blocking"); + } + } + + // Start listening + if (listen(listenfd, 256) != 0) { + usbmuxd_log(LL_FATAL, "listen() failed: %s", strerror(errno)); + return -1; + } + + usbmuxd_log(LL_INFO, "Listening on %s", listen_addr_str); + + return listenfd; +} + +static void handle_signal(int sig) +{ + if (sig != SIGUSR1 && sig != SIGUSR2) { + usbmuxd_log(LL_NOTICE,"Caught signal %d, exiting", sig); + should_exit = 1; + } else { + if(opt_enable_exit) { + if (sig == SIGUSR1) { + usbmuxd_log(LL_INFO, "Caught SIGUSR1, checking if we can terminate (no more devices attached)..."); + if (device_get_count(1) > 0) { + // we can't quit, there are still devices attached. + usbmuxd_log(LL_NOTICE, "Refusing to terminate, there are still devices attached. Kill me with signal 15 (TERM) to force quit."); + } else { + // it's safe to quit + should_exit = 1; + } + } else if (sig == SIGUSR2) { + usbmuxd_log(LL_INFO, "Caught SIGUSR2, scheduling device discovery"); + should_discover = 1; + } + } else { + usbmuxd_log(LL_INFO, "Caught SIGUSR1/2 but this instance was not started with \"--enable-exit\", ignoring."); + } + } +} + +static void set_signal_handlers(void) +{ + struct sigaction sa; + sigset_t set; + + // Mask all signals we handle. They will be unmasked by ppoll(). + sigemptyset(&set); + sigaddset(&set, SIGINT); + sigaddset(&set, SIGQUIT); + sigaddset(&set, SIGTERM); + sigaddset(&set, SIGUSR1); + sigaddset(&set, SIGUSR2); + sigprocmask(SIG_SETMASK, &set, NULL); + + memset(&sa, 0, sizeof(struct sigaction)); + sa.sa_handler = handle_signal; + sigaction(SIGINT, &sa, NULL); + sigaction(SIGQUIT, &sa, NULL); + sigaction(SIGTERM, &sa, NULL); + sigaction(SIGUSR1, &sa, NULL); + sigaction(SIGUSR2, &sa, NULL); +} + +#ifndef HAVE_PPOLL +static int ppoll(struct pollfd *fds, nfds_t nfds, const struct timespec *timeout, const sigset_t *sigmask) +{ + int ready; + sigset_t origmask; + int to = timeout->tv_sec*1000 + timeout->tv_nsec/1000000; + + sigprocmask(SIG_SETMASK, sigmask, &origmask); + ready = poll(fds, nfds, to); + sigprocmask(SIG_SETMASK, &origmask, NULL); + + return ready; +} +#endif + +static int main_loop(int listenfd) +{ + int to, cnt, i, dto; + struct fdlist pollfds; + struct timespec tspec; + + sigset_t empty_sigset; + sigemptyset(&empty_sigset); // unmask all signals + + fdlist_create(&pollfds); + while(!should_exit) { + usbmuxd_log(LL_FLOOD, "main_loop iteration"); + to = usb_get_timeout(); + usbmuxd_log(LL_FLOOD, "USB timeout is %d ms", to); + dto = device_get_timeout(); + usbmuxd_log(LL_FLOOD, "Device timeout is %d ms", dto); + if(dto < to) + to = dto; + + fdlist_reset(&pollfds); + fdlist_add(&pollfds, FD_LISTEN, listenfd, POLLIN); + usb_get_fds(&pollfds); + client_get_fds(&pollfds); + usbmuxd_log(LL_FLOOD, "fd count is %d", pollfds.count); + + tspec.tv_sec = to / 1000; + tspec.tv_nsec = (to % 1000) * 1000000; + cnt = ppoll(pollfds.fds, pollfds.count, &tspec, &empty_sigset); + usbmuxd_log(LL_FLOOD, "poll() returned %d", cnt); + if(cnt == -1) { + if(errno == EINTR) { + if(should_exit) { + usbmuxd_log(LL_INFO, "Event processing interrupted"); + break; + } + if(should_discover) { + should_discover = 0; + usbmuxd_log(LL_INFO, "Device discovery triggered"); + usb_discover(); + } + } + } else if(cnt == 0) { + if(usb_process() < 0) { + usbmuxd_log(LL_FATAL, "usb_process() failed"); + fdlist_free(&pollfds); + return -1; + } + device_check_timeouts(); + } else { + int done_usb = 0; + for(i=0; i<pollfds.count; i++) { + if(pollfds.fds[i].revents) { + if(!done_usb && pollfds.owners[i] == FD_USB) { + if(usb_process() < 0) { + usbmuxd_log(LL_FATAL, "usb_process() failed"); + fdlist_free(&pollfds); + return -1; + } + done_usb = 1; + } + if(pollfds.owners[i] == FD_LISTEN) { + if(client_accept(listenfd) < 0) { + usbmuxd_log(LL_FATAL, "client_accept() failed"); + fdlist_free(&pollfds); + return -1; + } + } + if(pollfds.owners[i] == FD_CLIENT) { + client_process(pollfds.fds[i].fd, pollfds.fds[i].revents); + } + } + } + } + } + fdlist_free(&pollfds); + return 0; +} + +/** + * make this program run detached from the current console + */ +static int daemonize(void) +{ + pid_t pid; + pid_t sid; + int pfd[2]; + int res; + + // already a daemon + if (getppid() == 1) + return 0; + + if((res = pipe(pfd)) < 0) { + usbmuxd_log(LL_FATAL, "pipe() failed."); + return res; + } + + pid = fork(); + if (pid < 0) { + usbmuxd_log(LL_FATAL, "fork() failed."); + return pid; + } + + if (pid > 0) { + // exit parent process + int status; + close(pfd[1]); + + if((res = read(pfd[0],&status,sizeof(int))) != sizeof(int)) { + fprintf(stderr, "usbmuxd: ERROR: Failed to get init status from child, check syslog for messages.\n"); + exit(1); + } + if(status != 0) + fprintf(stderr, "usbmuxd: ERROR: Child process exited with error %d, check syslog for messages.\n", status); + exit(status); + } + // At this point we are executing as the child process + // but we need to do one more fork + + daemon_pipe = pfd[1]; + close(pfd[0]); + report_to_parent = 1; + + // Create a new SID for the child process + sid = setsid(); + if (sid < 0) { + usbmuxd_log(LL_FATAL, "setsid() failed."); + return -1; + } + + pid = fork(); + if (pid < 0) { + usbmuxd_log(LL_FATAL, "fork() failed (second)."); + return pid; + } + + if (pid > 0) { + // exit parent process + close(daemon_pipe); + exit(0); + } + + // Change the current working directory. + if ((chdir("/")) < 0) { + usbmuxd_log(LL_FATAL, "chdir() failed"); + return -2; + } + // Redirect standard files to /dev/null + if (!freopen("/dev/null", "r", stdin)) { + usbmuxd_log(LL_FATAL, "Redirection of stdin failed."); + return -3; + } + if (!freopen("/dev/null", "w", stdout)) { + usbmuxd_log(LL_FATAL, "Redirection of stdout failed."); + return -3; + } + + return 0; +} + +static int notify_parent(int status) +{ + int res; + + report_to_parent = 0; + if ((res = write(daemon_pipe, &status, sizeof(int))) != sizeof(int)) { + usbmuxd_log(LL_FATAL, "Could not notify parent!"); + if(res >= 0) + return -2; + else + return res; + } + close(daemon_pipe); + if (!freopen("/dev/null", "w", stderr)) { + usbmuxd_log(LL_FATAL, "Redirection of stderr failed."); + return -1; + } + return 0; +} + +static void usage() +{ + printf("Usage: %s [OPTIONS]\n", PACKAGE_NAME); + printf("\n"); + printf("Expose a socket to multiplex connections from and to iOS devices.\n"); + printf("\n"); + printf("OPTIONS:\n"); + printf(" -h, --help\t\tPrint this message.\n"); + printf(" -v, --verbose\t\tBe verbose (use twice or more to increase).\n"); + printf(" -f, --foreground\tDo not daemonize (implies one -v).\n"); + printf(" -U, --user USER\tChange to this user after startup (needs USB privileges).\n"); + printf(" -n, --disable-hotplug\tDisables automatic discovery of devices on hotplug.\n"); + printf(" \tStarting another instance will trigger discovery instead.\n"); + printf(" -z, --enable-exit\tEnable \"--exit\" request from other instances and exit\n"); + printf(" \tautomatically if no device is attached.\n"); + printf(" -p, --no-preflight\tDisable lockdownd preflight on new device.\n"); +#ifdef HAVE_UDEV + printf(" -u, --udev\t\tRun in udev operation mode (implies -n and -z).\n"); +#endif +#ifdef HAVE_SYSTEMD + printf(" -s, --systemd\t\tRun in systemd operation mode (implies -z and -f).\n"); +#endif + printf(" -S, --socket ADDR:PORT | PATH Specify source ADDR and PORT or a UNIX\n"); + printf(" \t\tsocket PATH to use for the listening socket.\n"); + printf(" \t\tDefault: %s\n", socket_path); + printf(" -P, --pidfile PATH\tSpecify a different location for the pid file, or pass\n"); + printf(" \t\tNONE to disable. Default: %s\n", DEFAULT_LOCKFILE); + printf(" -x, --exit\t\tNotify a running instance to exit if there are no devices\n"); + printf(" \t\tconnected (sends SIGUSR1 to running instance) and exit.\n"); + printf(" -X, --force-exit\tNotify a running instance to exit even if there are still\n"); + printf(" \tdevices connected (always works) and exit.\n"); + printf(" -l, --logfile=LOGFILE\tLog (append) to LOGFILE instead of stderr or syslog.\n"); + printf(" -V, --version\t\tPrint version information and exit.\n"); + printf("\n"); + printf("Homepage: <" PACKAGE_URL ">\n"); + printf("Bug Reports: <" PACKAGE_BUGREPORT ">\n"); +} + +static void parse_opts(int argc, char **argv) +{ + static struct option longopts[] = { + {"help", no_argument, NULL, 'h'}, + {"foreground", no_argument, NULL, 'f'}, + {"verbose", no_argument, NULL, 'v'}, + {"user", required_argument, NULL, 'U'}, + {"disable-hotplug", no_argument, NULL, 'n'}, + {"enable-exit", no_argument, NULL, 'z'}, + {"no-preflight", no_argument, NULL, 'p'}, +#ifdef HAVE_UDEV + {"udev", no_argument, NULL, 'u'}, +#endif +#ifdef HAVE_SYSTEMD + {"systemd", no_argument, NULL, 's'}, +#endif + {"socket", required_argument, NULL, 'S'}, + {"pidfile", required_argument, NULL, 'P'}, + {"exit", no_argument, NULL, 'x'}, + {"force-exit", no_argument, NULL, 'X'}, + {"logfile", required_argument, NULL, 'l'}, + {"version", no_argument, NULL, 'V'}, + {NULL, 0, NULL, 0} + }; + int c; + +#ifdef HAVE_SYSTEMD + const char* opts_spec = "hfvVuU:xXsnzl:pS:P:"; +#elif HAVE_UDEV + const char* opts_spec = "hfvVuU:xXnzl:pS:P:"; +#else + const char* opts_spec = "hfvVU:xXnzl:pS:P:"; +#endif + + while (1) { + c = getopt_long(argc, argv, opts_spec, longopts, (int *) 0); + if (c == -1) { + break; + } + + switch (c) { + case 'h': + usage(); + exit(0); + case 'f': + foreground = 1; + break; + case 'v': + ++verbose; + break; + case 'V': + printf("%s\n", PACKAGE_STRING); + exit(0); + case 'U': + drop_privileges = 1; + drop_user = optarg; + break; + case 'p': + no_preflight = 1; + break; +#ifdef HAVE_UDEV + case 'u': + opt_disable_hotplug = 1; + opt_enable_exit = 1; + break; +#endif +#ifdef HAVE_SYSTEMD + case 's': + opt_enable_exit = 1; + foreground = 1; + break; +#endif + case 'n': + opt_disable_hotplug = 1; + break; + case 'z': + opt_enable_exit = 1; + break; + case 'S': + if (!*optarg || *optarg == '-') { + usbmuxd_log(LL_FATAL, "ERROR: --socket requires an argument"); + usage(); + exit(2); + } + listen_addr = optarg; + break; + case 'P': + if (!*optarg || *optarg == '-') { + usbmuxd_log(LL_FATAL, "ERROR: --pidfile requires an argument"); + usage(); + exit(2); + } + if (!strcmp(optarg, "NONE")) { + lockfile = NULL; + } else { + lockfile = optarg; + } + break; + case 'x': + opt_exit = 1; + exit_signal = SIGUSR1; + break; + case 'X': + opt_exit = 1; + exit_signal = SIGTERM; + break; + case 'l': + if (!*optarg) { + usbmuxd_log(LL_FATAL, "ERROR: --logfile requires a non-empty filename"); + usage(); + exit(2); + } + if (use_logfile) { + usbmuxd_log(LL_FATAL, "ERROR: --logfile cannot be used multiple times"); + exit(2); + } + if (!freopen(optarg, "a", stderr)) { + usbmuxd_log(LL_FATAL, "ERROR: fdreopen: %s", strerror(errno)); + } else { + use_logfile = 1; + } + break; + default: + usage(); + exit(2); + } + } +} + +int main(int argc, char *argv[]) +{ + int listenfd; + int res = 0; + int lfd; + struct flock lock; + char pids[10]; + + parse_opts(argc, argv); + + argc -= optind; + argv += optind; + + if (!foreground && !use_logfile) { + verbose += LL_WARNING; + log_enable_syslog(); + } else { + verbose += LL_NOTICE; + } + + /* set log level to specified verbosity */ + log_level = verbose; + + usbmuxd_log(LL_NOTICE, "usbmuxd v%s starting up", PACKAGE_VERSION); + should_exit = 0; + should_discover = 0; + + set_signal_handlers(); + signal(SIGPIPE, SIG_IGN); + + if (lockfile) { + res = lfd = open(lockfile, O_WRONLY|O_CREAT, 0644); + if(res == -1) { + usbmuxd_log(LL_FATAL, "Could not open lockfile"); + goto terminate; + } + lock.l_type = F_WRLCK; + lock.l_whence = SEEK_SET; + lock.l_start = 0; + lock.l_len = 0; + lock.l_pid = 0; + fcntl(lfd, F_GETLK, &lock); + close(lfd); + } + if (lockfile && lock.l_type != F_UNLCK) { + if (opt_exit) { + if (lock.l_pid && !kill(lock.l_pid, 0)) { + usbmuxd_log(LL_NOTICE, "Sending signal %d to instance with pid %d", exit_signal, lock.l_pid); + res = 0; + if (kill(lock.l_pid, exit_signal) < 0) { + usbmuxd_log(LL_FATAL, "Could not deliver signal %d to pid %d", exit_signal, lock.l_pid); + res = -1; + } + goto terminate; + } else { + usbmuxd_log(LL_ERROR, "Could not determine pid of the other running instance!"); + res = -1; + goto terminate; + } + } else { + if (!opt_disable_hotplug) { + usbmuxd_log(LL_ERROR, "Another instance is already running (pid %d). exiting.", lock.l_pid); + res = -1; + } else { + usbmuxd_log(LL_NOTICE, "Another instance is already running (pid %d). Telling it to check for devices.", lock.l_pid); + if (lock.l_pid && !kill(lock.l_pid, 0)) { + usbmuxd_log(LL_NOTICE, "Sending signal SIGUSR2 to instance with pid %d", lock.l_pid); + res = 0; + if (kill(lock.l_pid, SIGUSR2) < 0) { + usbmuxd_log(LL_FATAL, "Could not deliver SIGUSR2 to pid %d", lock.l_pid); + res = -1; + } + } else { + usbmuxd_log(LL_ERROR, "Could not determine pid of the other running instance!"); + res = -1; + } + } + goto terminate; + } + } + if (lockfile) { + unlink(lockfile); + } + + if (opt_exit) { + usbmuxd_log(LL_NOTICE, "No running instance found, none killed. Exiting."); + goto terminate; + } + + if (!foreground) { + if ((res = daemonize()) < 0) { + fprintf(stderr, "usbmuxd: FATAL: Could not daemonize!\n"); + usbmuxd_log(LL_FATAL, "Could not daemonize!"); + goto terminate; + } + } + + if (lockfile) { + // now open the lockfile and place the lock + res = lfd = open(lockfile, O_WRONLY|O_CREAT|O_TRUNC|O_EXCL, 0644); + if(res < 0) { + usbmuxd_log(LL_FATAL, "Could not open pidfile '%s'", lockfile); + goto terminate; + } + lock.l_type = F_WRLCK; + lock.l_whence = SEEK_SET; + lock.l_start = 0; + lock.l_len = 0; + if ((res = fcntl(lfd, F_SETLK, &lock)) < 0) { + usbmuxd_log(LL_FATAL, "Locking pidfile '%s' failed!", lockfile); + goto terminate; + } + sprintf(pids, "%d", getpid()); + if ((size_t)(res = write(lfd, pids, strlen(pids))) != strlen(pids)) { + usbmuxd_log(LL_FATAL, "Could not write pidfile!"); + if(res >= 0) + res = -2; + goto terminate; + } + } + + // set number of file descriptors to higher value + struct rlimit rlim; + getrlimit(RLIMIT_NOFILE, &rlim); + rlim.rlim_max = 65536; + setrlimit(RLIMIT_NOFILE, (const struct rlimit*)&rlim); + + usbmuxd_log(LL_INFO, "Creating socket"); + res = listenfd = create_socket(); + if(listenfd < 0) + goto terminate; + +#ifdef HAVE_LIBIMOBILEDEVICE + const char* userprefdir = config_get_config_dir(); + struct stat fst; + memset(&fst, '\0', sizeof(struct stat)); + if (stat(userprefdir, &fst) < 0) { + if (mkdir(userprefdir, 0775) < 0) { + usbmuxd_log(LL_FATAL, "Failed to create required directory '%s': %s", userprefdir, strerror(errno)); + res = -1; + goto terminate; + } + if (stat(userprefdir, &fst) < 0) { + usbmuxd_log(LL_FATAL, "stat() failed after creating directory '%s': %s", userprefdir, strerror(errno)); + res = -1; + goto terminate; + } + } + + // make sure permission bits are set correctly + if (fst.st_mode != 02775) { + if (chmod(userprefdir, 02775) < 0) { + usbmuxd_log(LL_WARNING, "chmod(%s, 02775) failed: %s", userprefdir, strerror(errno)); + } + } +#endif + + // drop elevated privileges + if (drop_privileges && (getuid() == 0 || geteuid() == 0)) { + struct passwd *pw; + if (!drop_user) { + usbmuxd_log(LL_FATAL, "No user to drop privileges to?"); + res = -1; + goto terminate; + } + pw = getpwnam(drop_user); + if (!pw) { + usbmuxd_log(LL_FATAL, "Dropping privileges failed, check if user '%s' exists!", drop_user); + res = -1; + goto terminate; + } + if (pw->pw_uid == 0) { + usbmuxd_log(LL_INFO, "Not dropping privileges to root"); + } else { +#ifdef HAVE_LIBIMOBILEDEVICE + /* make sure the non-privileged user has proper access to the config directory */ + if ((fst.st_uid != pw->pw_uid) || (fst.st_gid != pw->pw_gid)) { + if (chown(userprefdir, pw->pw_uid, pw->pw_gid) < 0) { + usbmuxd_log(LL_WARNING, "chown(%s, %d, %d) failed: %s", userprefdir, pw->pw_uid, pw->pw_gid, strerror(errno)); + } + } +#endif + + if ((res = initgroups(drop_user, pw->pw_gid)) < 0) { + usbmuxd_log(LL_FATAL, "Failed to drop privileges (cannot set supplementary groups)"); + goto terminate; + } + if ((res = setgid(pw->pw_gid)) < 0) { + usbmuxd_log(LL_FATAL, "Failed to drop privileges (cannot set group ID to %d)", pw->pw_gid); + goto terminate; + } + if ((res = setuid(pw->pw_uid)) < 0) { + usbmuxd_log(LL_FATAL, "Failed to drop privileges (cannot set user ID to %d)", pw->pw_uid); + goto terminate; + } + + // security check + if (setuid(0) != -1) { + usbmuxd_log(LL_FATAL, "Failed to drop privileges properly!"); + res = -1; + goto terminate; + } + if (getuid() != pw->pw_uid || getgid() != pw->pw_gid) { + usbmuxd_log(LL_FATAL, "Failed to drop privileges properly!"); + res = -1; + goto terminate; + } + usbmuxd_log(LL_NOTICE, "Successfully dropped privileges to '%s'", drop_user); + } + } + + client_init(); + device_init(); + usbmuxd_log(LL_INFO, "Initializing USB"); + if((res = usb_init()) < 0) + goto terminate; + + usbmuxd_log(LL_INFO, "%d device%s detected", res, (res==1)?"":"s"); + + usbmuxd_log(LL_NOTICE, "Initialization complete"); + + if (report_to_parent) + if((res = notify_parent(0)) < 0) + goto terminate; + + if(opt_disable_hotplug) { + usbmuxd_log(LL_NOTICE, "Automatic device discovery on hotplug disabled."); + usb_autodiscover(0); // discovery to be triggered by new instance + } + if (opt_enable_exit) { + usbmuxd_log(LL_NOTICE, "Enabled exit on SIGUSR1 if no devices are attached. Start a new instance with \"--exit\" to trigger."); + } + + res = main_loop(listenfd); + if(res < 0) + usbmuxd_log(LL_FATAL, "main_loop failed"); + + usbmuxd_log(LL_NOTICE, "usbmuxd shutting down"); + device_kill_connections(); + usb_shutdown(); + device_shutdown(); + client_shutdown(); + usbmuxd_log(LL_NOTICE, "Shutdown complete"); + +terminate: + log_disable_syslog(); + + if (res < 0) + res = -res; + else + res = 0; + if (report_to_parent) + notify_parent(res); + + return res; +} |