diff options
Diffstat (limited to 'src/tty-ask-password-agent/tty-ask-password-agent.c')
-rw-r--r-- | src/tty-ask-password-agent/tty-ask-password-agent.c | 551 |
1 files changed, 390 insertions, 161 deletions
diff --git a/src/tty-ask-password-agent/tty-ask-password-agent.c b/src/tty-ask-password-agent/tty-ask-password-agent.c index 73b19d8e89..b45490be1a 100644 --- a/src/tty-ask-password-agent/tty-ask-password-agent.c +++ b/src/tty-ask-password-agent/tty-ask-password-agent.c @@ -1,9 +1,8 @@ -/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ - /*** This file is part of systemd. Copyright 2010 Lennart Poettering + Copyright 2015 Werner Fink systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by @@ -19,32 +18,43 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ -#include <stdbool.h> #include <errno.h> +#include <fcntl.h> +#include <getopt.h> +#include <poll.h> +#include <signal.h> +#include <stdbool.h> +#include <stddef.h> #include <string.h> +#include <sys/inotify.h> +#include <sys/prctl.h> +#include <sys/signalfd.h> #include <sys/socket.h> +#include <sys/wait.h> #include <sys/un.h> -#include <stddef.h> -#include <poll.h> -#include <sys/inotify.h> #include <unistd.h> -#include <getopt.h> -#include <sys/signalfd.h> -#include <fcntl.h> -#include "util.h" +#include "alloc-util.h" +#include "ask-password-api.h" +#include "conf-parser.h" +#include "def.h" +#include "dirent-util.h" +#include "exit-status.h" +#include "fd-util.h" +#include "fileio.h" +#include "hashmap.h" +#include "io-util.h" +#include "macro.h" #include "mkdir.h" #include "path-util.h" -#include "conf-parser.h" -#include "utmp-wtmp.h" +#include "process-util.h" +#include "signal-util.h" #include "socket-util.h" -#include "ask-password-api.h" +#include "string-util.h" #include "strv.h" -#include "build.h" -#include "def.h" -#include "process-util.h" #include "terminal-util.h" -#include "signal-util.h" +#include "util.h" +#include "utmp-wtmp.h" static enum { ACTION_LIST, @@ -55,16 +65,17 @@ static enum { static bool arg_plymouth = false; static bool arg_console = false; +static const char *arg_device = NULL; static int ask_password_plymouth( const char *message, usec_t until, + AskPasswordFlags flags, const char *flag_file, - bool accept_cached, - char ***_passphrases) { + char ***ret) { + static const union sockaddr_union sa = PLYMOUTH_SOCKET; _cleanup_close_ int fd = -1, notify = -1; - union sockaddr_union sa = PLYMOUTH_SOCKET; _cleanup_free_ char *packet = NULL; ssize_t k; int r, n; @@ -76,7 +87,7 @@ static int ask_password_plymouth( POLL_INOTIFY }; - assert(_passphrases); + assert(ret); if (flag_file) { notify = inotify_init1(IN_CLOEXEC|IN_NONBLOCK); @@ -92,19 +103,17 @@ static int ask_password_plymouth( if (fd < 0) return -errno; - r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + 1 + strlen(sa.un.sun_path+1)); + r = connect(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)); if (r < 0) - return log_error_errno(errno, "Failed to connect to Plymouth: %m"); + return -errno; - if (accept_cached) { + if (flags & ASK_PASSWORD_ACCEPT_CACHED) { packet = strdup("c"); n = 1; - } else if (asprintf(&packet, "*\002%c%s%n", (int) (strlen(message) + 1), - message, &n) < 0) + } else if (asprintf(&packet, "*\002%c%s%n", (int) (strlen(message) + 1), message, &n) < 0) packet = NULL; - if (!packet) - return log_oom(); + return -ENOMEM; r = loop_write(fd, packet, n + 1, true); if (r < 0) @@ -123,33 +132,48 @@ static int ask_password_plymouth( y = now(CLOCK_MONOTONIC); - if (y > until) - return -ETIME; + if (y > until) { + r = -ETIME; + goto finish; + } sleep_for = (int) ((until - y) / USEC_PER_MSEC); } - if (flag_file && access(flag_file, F_OK) < 0) - return -errno; + if (flag_file && access(flag_file, F_OK) < 0) { + r = -errno; + goto finish; + } - j = poll(pollfd, notify > 0 ? 2 : 1, sleep_for); + j = poll(pollfd, notify >= 0 ? 2 : 1, sleep_for); if (j < 0) { if (errno == EINTR) continue; - return -errno; - } else if (j == 0) - return -ETIME; + r = -errno; + goto finish; + } else if (j == 0) { + r = -ETIME; + goto finish; + } - if (notify > 0 && pollfd[POLL_INOTIFY].revents != 0) + if (notify >= 0 && pollfd[POLL_INOTIFY].revents != 0) flush_fd(notify); if (pollfd[POLL_SOCKET].revents == 0) continue; k = read(fd, buffer + p, sizeof(buffer) - p); - if (k <= 0) - return r = k < 0 ? -errno : -EIO; + if (k < 0) { + if (errno == EINTR || errno == EAGAIN) + continue; + + r = -errno; + goto finish; + } else if (k == 0) { + r = -EIO; + goto finish; + } p += k; @@ -158,27 +182,29 @@ static int ask_password_plymouth( if (buffer[0] == 5) { - if (accept_cached) { + if (flags & ASK_PASSWORD_ACCEPT_CACHED) { /* Hmm, first try with cached * passwords failed, so let's retry * with a normal password request */ - free(packet); - packet = NULL; + packet = mfree(packet); - if (asprintf(&packet, "*\002%c%s%n", (int) (strlen(message) + 1), message, &n) < 0) - return -ENOMEM; + if (asprintf(&packet, "*\002%c%s%n", (int) (strlen(message) + 1), message, &n) < 0) { + r = -ENOMEM; + goto finish; + } r = loop_write(fd, packet, n+1, true); if (r < 0) - return r; + goto finish; - accept_cached = false; + flags &= ~ASK_PASSWORD_ACCEPT_CACHED; p = 0; continue; } /* No password, because UI not shown */ - return -ENOENT; + r = -ENOENT; + goto finish; } else if (buffer[0] == 2 || buffer[0] == 9) { uint32_t size; @@ -190,32 +216,82 @@ static int ask_password_plymouth( memcpy(&size, buffer+1, sizeof(size)); size = le32toh(size); - if (size + 5 > sizeof(buffer)) - return -EIO; + if (size + 5 > sizeof(buffer)) { + r = -EIO; + goto finish; + } if (p-5 < size) continue; l = strv_parse_nulstr(buffer + 5, size); - if (!l) - return -ENOMEM; + if (!l) { + r = -ENOMEM; + goto finish; + } - *_passphrases = l; + *ret = l; break; - } else + } else { /* Unknown packet */ - return -EIO; + r = -EIO; + goto finish; + } } - return 0; + r = 0; + +finish: + memory_erase(buffer, sizeof(buffer)); + return r; +} + +static int send_passwords(const char *socket_name, char **passwords) { + _cleanup_free_ char *packet = NULL; + _cleanup_close_ int socket_fd = -1; + union sockaddr_union sa = { .un.sun_family = AF_UNIX }; + size_t packet_length = 1; + char **p, *d; + int r; + + assert(socket_name); + + STRV_FOREACH(p, passwords) + packet_length += strlen(*p) + 1; + + packet = new(char, packet_length); + if (!packet) + return -ENOMEM; + + packet[0] = '+'; + + d = packet + 1; + STRV_FOREACH(p, passwords) + d = stpcpy(d, *p) + 1; + + socket_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0); + if (socket_fd < 0) { + r = log_debug_errno(errno, "socket(): %m"); + goto finish; + } + + strncpy(sa.un.sun_path, socket_name, sizeof(sa.un.sun_path)); + + r = sendto(socket_fd, packet, packet_length, MSG_NOSIGNAL, &sa.sa, SOCKADDR_UN_LEN(sa.un)); + if (r < 0) + r = log_debug_errno(errno, "sendto(): %m"); + +finish: + memory_erase(packet, packet_length); + return r; } static int parse_password(const char *filename, char **wall) { - _cleanup_free_ char *socket_name = NULL, *message = NULL, *packet = NULL; + _cleanup_free_ char *socket_name = NULL, *message = NULL; + bool accept_cached = false, echo = false; uint64_t not_after = 0; unsigned pid = 0; - bool accept_cached = false, echo = false; const ConfigTableItem items[] = { { "Ask", "Socket", config_parse_string, 0, &socket_name }, @@ -258,7 +334,7 @@ static int parse_password(const char *filename, char **wall) { if (asprintf(&_wall, "%s%sPassword entry required for \'%s\' (PID %u).\r\n" "Please enter password with the systemd-tty-ask-password-agent tool!", - *wall ? *wall : "", + strempty(*wall), *wall ? "\r\n\r\n" : "", message, pid) < 0) @@ -268,9 +344,7 @@ static int parse_password(const char *filename, char **wall) { *wall = _wall; } else { - union sockaddr_union sa = {}; - size_t packet_length = 0; - _cleanup_close_ int socket_fd = -1; + _cleanup_strv_free_erase_ char **passwords = NULL; assert(arg_action == ACTION_QUERY || arg_action == ACTION_WATCH); @@ -282,79 +356,48 @@ static int parse_password(const char *filename, char **wall) { return 0; } - if (arg_plymouth) { - _cleanup_strv_free_ char **passwords = NULL; - - r = ask_password_plymouth(message, not_after, filename, accept_cached, &passwords); - if (r >= 0) { - char **p; - - packet_length = 1; - STRV_FOREACH(p, passwords) - packet_length += strlen(*p) + 1; - - packet = new(char, packet_length); - if (!packet) - r = -ENOMEM; - else { - char *d = packet + 1; - - STRV_FOREACH(p, passwords) - d = stpcpy(d, *p) + 1; - - packet[0] = '+'; - } - } - - } else { + if (arg_plymouth) + r = ask_password_plymouth(message, not_after, accept_cached ? ASK_PASSWORD_ACCEPT_CACHED : 0, filename, &passwords); + else { + char *password = NULL; int tty_fd = -1; - _cleanup_free_ char *password = NULL; if (arg_console) { - tty_fd = acquire_terminal("/dev/console", false, false, false, USEC_INFINITY); + const char *con = arg_device ? arg_device : "/dev/console"; + + tty_fd = acquire_terminal(con, false, false, false, USEC_INFINITY); if (tty_fd < 0) - return tty_fd; + return log_error_errno(tty_fd, "Failed to acquire /dev/console: %m"); + + r = reset_terminal_fd(tty_fd, true); + if (r < 0) + log_warning_errno(r, "Failed to reset terminal, ignoring: %m"); } - r = ask_password_tty(message, not_after, echo, filename, &password); + r = ask_password_tty(message, NULL, not_after, echo ? ASK_PASSWORD_ECHO : 0, filename, &password); if (arg_console) { - safe_close(tty_fd); + tty_fd = safe_close(tty_fd); release_terminal(); } - if (r >= 0) { - packet_length = 1 + strlen(password) + 1; - packet = new(char, packet_length); - if (!packet) - r = -ENOMEM; - else { - packet[0] = '+'; - strcpy(packet + 1, password); - } - } + if (r >= 0) + r = strv_push(&passwords, password); + + if (r < 0) + string_free_erase(password); } + /* If the query went away, that's OK */ if (IN_SET(r, -ETIME, -ENOENT)) - /* If the query went away, that's OK */ return 0; if (r < 0) return log_error_errno(r, "Failed to query password: %m"); - socket_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0); - if (socket_fd < 0) - return log_error_errno(errno, "socket(): %m"); - - sa.un.sun_family = AF_UNIX; - strncpy(sa.un.sun_path, socket_name, sizeof(sa.un.sun_path)); - - r = sendto(socket_fd, packet, packet_length, MSG_NOSIGNAL, &sa.sa, - offsetof(struct sockaddr_un, sun_path) + strlen(socket_name)); - if (r < 0) { - log_error_errno(errno, "Failed to send: %m"); - return r; - } + r = send_passwords(socket_name, passwords); + if (r < 0) + return log_error_errno(r, "Failed to send: %m"); } return 0; @@ -362,40 +405,45 @@ static int parse_password(const char *filename, char **wall) { static int wall_tty_block(void) { _cleanup_free_ char *p = NULL; - int fd, r; dev_t devnr; + int fd, r; r = get_ctty_devnr(0, &devnr); + if (r == -ENXIO) /* We have no controlling tty */ + return -ENOTTY; if (r < 0) - return r; + return log_error_errno(r, "Failed to get controlling TTY: %m"); if (asprintf(&p, "/run/systemd/ask-password-block/%u:%u", major(devnr), minor(devnr)) < 0) - return -ENOMEM; + return log_oom(); mkdir_parents_label(p, 0700); mkfifo(p, 0600); fd = open(p, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); if (fd < 0) - return -errno; + return log_debug_errno(errno, "Failed to open %s: %m", p); return fd; } static bool wall_tty_match(const char *path, void *userdata) { - int fd, r; - struct stat st; _cleanup_free_ char *p = NULL; + _cleanup_close_ int fd = -1; + struct stat st; if (!path_is_absolute(path)) path = strjoina("/dev/", path); - r = lstat(path, &st); - if (r < 0) + if (lstat(path, &st) < 0) { + log_debug_errno(errno, "Failed to stat %s: %m", path); return true; + } - if (!S_ISCHR(st.st_mode)) + if (!S_ISCHR(st.st_mode)) { + log_debug("%s is not a character device.", path); return true; + } /* We use named pipes to ensure that wall messages suggesting * password entry are not printed over password prompts @@ -405,16 +453,19 @@ static bool wall_tty_match(const char *path, void *userdata) { * advantage that the block will automatically go away if the * process dies. */ - if (asprintf(&p, "/run/systemd/ask-password-block/%u:%u", major(st.st_rdev), minor(st.st_rdev)) < 0) + if (asprintf(&p, "/run/systemd/ask-password-block/%u:%u", major(st.st_rdev), minor(st.st_rdev)) < 0) { + log_oom(); return true; + } fd = open(p, O_WRONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); - if (fd < 0) - return true; + if (fd < 0) { + log_debug_errno(errno, "Failed top open the wall pipe: %m"); + return 1; + } /* What, we managed to open the pipe? Then this tty is filtered. */ - safe_close(fd); - return false; + return 0; } static int show_passwords(void) { @@ -427,11 +478,10 @@ static int show_passwords(void) { if (errno == ENOENT) return 0; - log_error_errno(errno, "opendir(/run/systemd/ask-password): %m"); - return -errno; + return log_error_errno(errno, "Failed to open /run/systemd/ask-password: %m"); } - while ((de = readdir(d))) { + FOREACH_DIRENT_ALL(de, d, return log_error_errno(errno, "Failed to read directory: %m")) { _cleanup_free_ char *p = NULL, *wall = NULL; int q; @@ -441,7 +491,7 @@ static int show_passwords(void) { if (de->d_type != DT_REG) continue; - if (hidden_file(de->d_name)) + if (hidden_or_backup_file(de->d_name)) continue; if (!startswith(de->d_name, "ask.")) @@ -456,7 +506,7 @@ static int show_passwords(void) { r = q; if (wall) - utmp_wall(wall, NULL, NULL, wall_tty_match, NULL); + (void) utmp_wall(wall, NULL, NULL, wall_tty_match, NULL); } return r; @@ -476,14 +526,14 @@ static int watch_passwords(void) { tty_block_fd = wall_tty_block(); - mkdir_p_label("/run/systemd/ask-password", 0755); + (void) mkdir_p_label("/run/systemd/ask-password", 0755); notify = inotify_init1(IN_CLOEXEC); if (notify < 0) - return -errno; + return log_error_errno(errno, "Failed to allocate directory watch: %m"); if (inotify_add_watch(notify, "/run/systemd/ask-password", IN_CLOSE_WRITE|IN_MOVED_TO) < 0) - return -errno; + return log_error_errno(errno, "Failed to add /run/systemd/ask-password to directory watch: %m"); assert_se(sigemptyset(&mask) >= 0); assert_se(sigset_add_many(&mask, SIGINT, SIGTERM, -1) >= 0); @@ -491,7 +541,7 @@ static int watch_passwords(void) { signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC); if (signal_fd < 0) - return -errno; + return log_error_errno(errno, "Failed to allocate signal file descriptor: %m"); pollfd[FD_INOTIFY].fd = notify; pollfd[FD_INOTIFY].events = POLLIN; @@ -511,7 +561,7 @@ static int watch_passwords(void) { } if (pollfd[FD_INOTIFY].revents != 0) - flush_fd(notify); + (void) flush_fd(notify); if (pollfd[FD_SIGNAL].revents != 0) break; @@ -547,14 +597,14 @@ static int parse_argv(int argc, char *argv[]) { }; static const struct option options[] = { - { "help", no_argument, NULL, 'h' }, - { "version", no_argument, NULL, ARG_VERSION }, - { "list", no_argument, NULL, ARG_LIST }, - { "query", no_argument, NULL, ARG_QUERY }, - { "watch", no_argument, NULL, ARG_WATCH }, - { "wall", no_argument, NULL, ARG_WALL }, - { "plymouth", no_argument, NULL, ARG_PLYMOUTH }, - { "console", no_argument, NULL, ARG_CONSOLE }, + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "list", no_argument, NULL, ARG_LIST }, + { "query", no_argument, NULL, ARG_QUERY }, + { "watch", no_argument, NULL, ARG_WATCH }, + { "wall", no_argument, NULL, ARG_WALL }, + { "plymouth", no_argument, NULL, ARG_PLYMOUTH }, + { "console", optional_argument, NULL, ARG_CONSOLE }, {} }; @@ -572,9 +622,7 @@ static int parse_argv(int argc, char *argv[]) { return 0; case ARG_VERSION: - puts(PACKAGE_STRING); - puts(SYSTEMD_FEATURES); - return 0; + return version(); case ARG_LIST: arg_action = ACTION_LIST; @@ -598,6 +646,15 @@ static int parse_argv(int argc, char *argv[]) { case ARG_CONSOLE: arg_console = true; + if (optarg) { + + if (isempty(optarg)) { + log_error("Empty console device path is not allowed."); + return -EINVAL; + } + + arg_device = optarg; + } break; case '?': @@ -612,9 +669,171 @@ static int parse_argv(int argc, char *argv[]) { return -EINVAL; } + if (arg_plymouth || arg_console) { + + if (!IN_SET(arg_action, ACTION_QUERY, ACTION_WATCH)) { + log_error("Options --query and --watch conflict."); + return -EINVAL; + } + + if (arg_plymouth && arg_console) { + log_error("Options --plymouth and --console conflict."); + return -EINVAL; + } + } + return 1; } +/* + * To be able to ask on all terminal devices of /dev/console + * the devices are collected. If more than one device is found, + * then on each of the terminals a inquiring task is forked. + * Every task has its own session and its own controlling terminal. + * If one of the tasks does handle a password, the remaining tasks + * will be terminated. + */ +static int ask_on_this_console(const char *tty, pid_t *pid, int argc, char *argv[]) { + struct sigaction sig = { + .sa_handler = nop_signal_handler, + .sa_flags = SA_NOCLDSTOP | SA_RESTART, + }; + + assert_se(sigprocmask_many(SIG_UNBLOCK, NULL, SIGHUP, SIGCHLD, -1) >= 0); + + assert_se(sigemptyset(&sig.sa_mask) >= 0); + assert_se(sigaction(SIGCHLD, &sig, NULL) >= 0); + + sig.sa_handler = SIG_DFL; + assert_se(sigaction(SIGHUP, &sig, NULL) >= 0); + + *pid = fork(); + if (*pid < 0) + return log_error_errno(errno, "Failed to fork process: %m"); + + if (*pid == 0) { + int ac; + + assert_se(prctl(PR_SET_PDEATHSIG, SIGHUP) >= 0); + + reset_signal_mask(); + reset_all_signal_handlers(); + + for (ac = 0; ac < argc; ac++) { + if (streq(argv[ac], "--console")) { + argv[ac] = strjoina("--console=", tty, NULL); + break; + } + } + + assert(ac < argc); + + execv(SYSTEMD_TTY_ASK_PASSWORD_AGENT_BINARY_PATH, argv); + _exit(EXIT_FAILURE); + } + return 0; +} + +static void terminate_agents(Set *pids) { + struct timespec ts; + siginfo_t status = {}; + sigset_t set; + Iterator i; + void *p; + int r, signum; + + /* + * Request termination of the remaining processes as those + * are not required anymore. + */ + SET_FOREACH(p, pids, i) + (void) kill(PTR_TO_PID(p), SIGTERM); + + /* + * Collect the processes which have go away. + */ + assert_se(sigemptyset(&set) >= 0); + assert_se(sigaddset(&set, SIGCHLD) >= 0); + timespec_store(&ts, 50 * USEC_PER_MSEC); + + while (!set_isempty(pids)) { + + zero(status); + r = waitid(P_ALL, 0, &status, WEXITED|WNOHANG); + if (r < 0 && errno == EINTR) + continue; + + if (r == 0 && status.si_pid > 0) { + set_remove(pids, PID_TO_PTR(status.si_pid)); + continue; + } + + signum = sigtimedwait(&set, NULL, &ts); + if (signum < 0) { + if (errno != EAGAIN) + log_error_errno(errno, "sigtimedwait() failed: %m"); + break; + } + assert(signum == SIGCHLD); + } + + /* + * Kill hanging processes. + */ + SET_FOREACH(p, pids, i) { + log_warning("Failed to terminate child %d, killing it", PTR_TO_PID(p)); + (void) kill(PTR_TO_PID(p), SIGKILL); + } +} + +static int ask_on_consoles(int argc, char *argv[]) { + _cleanup_set_free_ Set *pids = NULL; + _cleanup_strv_free_ char **consoles = NULL; + siginfo_t status = {}; + char **tty; + pid_t pid; + int r; + + r = get_kernel_consoles(&consoles); + if (r < 0) + return log_error_errno(r, "Failed to determine devices of /dev/console: %m"); + + pids = set_new(NULL); + if (!pids) + return log_oom(); + + /* Start an agent on each console. */ + STRV_FOREACH(tty, consoles) { + r = ask_on_this_console(*tty, &pid, argc, argv); + if (r < 0) + return r; + + if (set_put(pids, PID_TO_PTR(pid)) < 0) + return log_oom(); + } + + /* Wait for an agent to exit. */ + for (;;) { + zero(status); + + if (waitid(P_ALL, 0, &status, WEXITED) < 0) { + if (errno == EINTR) + continue; + + return log_error_errno(errno, "waitid() failed: %m"); + } + + set_remove(pids, PID_TO_PTR(status.si_pid)); + break; + } + + if (!is_clean_exit(status.si_code, status.si_status, EXIT_CLEAN_DAEMON, NULL)) + log_error("Password agent failed with: %d", status.si_status); + + terminate_agents(pids); + return 0; +} + int main(int argc, char *argv[]) { int r; @@ -628,18 +847,28 @@ int main(int argc, char *argv[]) { if (r <= 0) goto finish; - if (arg_console) { - setsid(); - release_terminal(); - } - - if (IN_SET(arg_action, ACTION_WATCH, ACTION_WALL)) - r = watch_passwords(); - else - r = show_passwords(); + if (arg_console && !arg_device) + /* + * Spawn for each console device a separate process. + */ + r = ask_on_consoles(argc, argv); + else { + + if (arg_device) { + /* + * Later on, a controlling terminal will be acquired, + * therefore the current process has to become a session + * leader and should not have a controlling terminal already. + */ + (void) setsid(); + (void) release_terminal(); + } - if (r < 0) - log_error_errno(r, "Error: %m"); + if (IN_SET(arg_action, ACTION_WATCH, ACTION_WALL)) + r = watch_passwords(); + else + r = show_passwords(); + } finish: return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; |