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-rw-r--r--src/systemd-tty-ask-password-agent/Makefile32
-rw-r--r--src/systemd-tty-ask-password-agent/tty-ask-password-agent.c681
2 files changed, 713 insertions, 0 deletions
diff --git a/src/systemd-tty-ask-password-agent/Makefile b/src/systemd-tty-ask-password-agent/Makefile
new file mode 100644
index 0000000000..37b51da33b
--- /dev/null
+++ b/src/systemd-tty-ask-password-agent/Makefile
@@ -0,0 +1,32 @@
+# -*- Mode: makefile; indent-tabs-mode: t -*-
+#
+# This file is part of systemd.
+#
+# Copyright 2010-2012 Lennart Poettering
+# Copyright 2010-2012 Kay Sievers
+# Copyright 2013 Zbigniew Jędrzejewski-Szmek
+# Copyright 2013 David Strauss
+# Copyright 2016 Luke Shumaker
+#
+# 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
+# the Free Software Foundation; either version 2.1 of the License, or
+# (at your option) any later version.
+#
+# systemd 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with systemd; If not, see <http://www.gnu.org/licenses/>.
+include $(dir $(lastword $(MAKEFILE_LIST)))/../../config.mk
+include $(topsrcdir)/build-aux/Makefile.head.mk
+
+systemd_tty_ask_password_agent_SOURCES = \
+ src/tty-ask-password-agent/tty-ask-password-agent.c
+
+systemd_tty_ask_password_agent_LDADD = \
+ libshared.la
+
+include $(topsrcdir)/build-aux/Makefile.tail.mk
diff --git a/src/systemd-tty-ask-password-agent/tty-ask-password-agent.c b/src/systemd-tty-ask-password-agent/tty-ask-password-agent.c
new file mode 100644
index 0000000000..7b67831e54
--- /dev/null
+++ b/src/systemd-tty-ask-password-agent/tty-ask-password-agent.c
@@ -0,0 +1,681 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ 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
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <poll.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/inotify.h>
+#include <sys/signalfd.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "alloc-util.h"
+#include "ask-password-api.h"
+#include "conf-parser.h"
+#include "def.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "io-util.h"
+#include "mkdir.h"
+#include "path-util.h"
+#include "process-util.h"
+#include "signal-util.h"
+#include "socket-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "terminal-util.h"
+#include "util.h"
+#include "utmp-wtmp.h"
+
+static enum {
+ ACTION_LIST,
+ ACTION_QUERY,
+ ACTION_WATCH,
+ ACTION_WALL
+} arg_action = ACTION_QUERY;
+
+static bool arg_plymouth = false;
+static bool arg_console = false;
+
+static int ask_password_plymouth(
+ const char *message,
+ usec_t until,
+ AskPasswordFlags flags,
+ const char *flag_file,
+ char ***ret) {
+
+ _cleanup_close_ int fd = -1, notify = -1;
+ union sockaddr_union sa = PLYMOUTH_SOCKET;
+ _cleanup_free_ char *packet = NULL;
+ ssize_t k;
+ int r, n;
+ struct pollfd pollfd[2] = {};
+ char buffer[LINE_MAX];
+ size_t p = 0;
+ enum {
+ POLL_SOCKET,
+ POLL_INOTIFY
+ };
+
+ assert(ret);
+
+ if (flag_file) {
+ notify = inotify_init1(IN_CLOEXEC|IN_NONBLOCK);
+ if (notify < 0)
+ return -errno;
+
+ r = inotify_add_watch(notify, flag_file, IN_ATTRIB); /* for the link count */
+ if (r < 0)
+ return -errno;
+ }
+
+ fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (fd < 0)
+ return -errno;
+
+ r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + 1 + strlen(sa.un.sun_path+1));
+ if (r < 0)
+ return -errno;
+
+ 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)
+ packet = NULL;
+ if (!packet)
+ return -ENOMEM;
+
+ r = loop_write(fd, packet, n + 1, true);
+ if (r < 0)
+ return r;
+
+ pollfd[POLL_SOCKET].fd = fd;
+ pollfd[POLL_SOCKET].events = POLLIN;
+ pollfd[POLL_INOTIFY].fd = notify;
+ pollfd[POLL_INOTIFY].events = POLLIN;
+
+ for (;;) {
+ int sleep_for = -1, j;
+
+ if (until > 0) {
+ usec_t y;
+
+ y = now(CLOCK_MONOTONIC);
+
+ if (y > until) {
+ r = -ETIME;
+ goto finish;
+ }
+
+ sleep_for = (int) ((until - y) / USEC_PER_MSEC);
+ }
+
+ if (flag_file && access(flag_file, F_OK) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ j = poll(pollfd, notify >= 0 ? 2 : 1, sleep_for);
+ if (j < 0) {
+ if (errno == EINTR)
+ continue;
+
+ r = -errno;
+ goto finish;
+ } else if (j == 0) {
+ r = -ETIME;
+ goto finish;
+ }
+
+ 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) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+
+ r = -errno;
+ goto finish;
+ } else if (k == 0) {
+ r = -EIO;
+ goto finish;
+ }
+
+ p += k;
+
+ if (p < 1)
+ continue;
+
+ if (buffer[0] == 5) {
+
+ if (flags & ASK_PASSWORD_ACCEPT_CACHED) {
+ /* Hmm, first try with cached
+ * passwords failed, so let's retry
+ * with a normal password request */
+ packet = mfree(packet);
+
+ 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)
+ goto finish;
+
+ flags &= ~ASK_PASSWORD_ACCEPT_CACHED;
+ p = 0;
+ continue;
+ }
+
+ /* No password, because UI not shown */
+ r = -ENOENT;
+ goto finish;
+
+ } else if (buffer[0] == 2 || buffer[0] == 9) {
+ uint32_t size;
+ char **l;
+
+ /* One or more answers */
+ if (p < 5)
+ continue;
+
+ memcpy(&size, buffer+1, sizeof(size));
+ size = le32toh(size);
+ if (size + 5 > sizeof(buffer)) {
+ r = -EIO;
+ goto finish;
+ }
+
+ if (p-5 < size)
+ continue;
+
+ l = strv_parse_nulstr(buffer + 5, size);
+ if (!l) {
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ *ret = l;
+ break;
+
+ } else {
+ /* Unknown packet */
+ r = -EIO;
+ goto finish;
+ }
+ }
+
+ 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,
+ offsetof(struct sockaddr_un, sun_path) + strlen(socket_name));
+ 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;
+ bool accept_cached = false, echo = false;
+ uint64_t not_after = 0;
+ unsigned pid = 0;
+
+ const ConfigTableItem items[] = {
+ { "Ask", "Socket", config_parse_string, 0, &socket_name },
+ { "Ask", "NotAfter", config_parse_uint64, 0, &not_after },
+ { "Ask", "Message", config_parse_string, 0, &message },
+ { "Ask", "PID", config_parse_unsigned, 0, &pid },
+ { "Ask", "AcceptCached", config_parse_bool, 0, &accept_cached },
+ { "Ask", "Echo", config_parse_bool, 0, &echo },
+ {}
+ };
+
+ int r;
+
+ assert(filename);
+
+ r = config_parse(NULL, filename, NULL,
+ NULL,
+ config_item_table_lookup, items,
+ true, false, true, NULL);
+ if (r < 0)
+ return r;
+
+ if (!socket_name) {
+ log_error("Invalid password file %s", filename);
+ return -EBADMSG;
+ }
+
+ if (not_after > 0 && now(CLOCK_MONOTONIC) > not_after)
+ return 0;
+
+ if (pid > 0 && !pid_is_alive(pid))
+ return 0;
+
+ if (arg_action == ACTION_LIST)
+ printf("'%s' (PID %u)\n", message, pid);
+
+ else if (arg_action == ACTION_WALL) {
+ 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!",
+ strempty(*wall),
+ *wall ? "\r\n\r\n" : "",
+ message,
+ pid) < 0)
+ return log_oom();
+
+ free(*wall);
+ *wall = _wall;
+
+ } else {
+ _cleanup_strv_free_erase_ char **passwords = NULL;
+
+ assert(arg_action == ACTION_QUERY ||
+ arg_action == ACTION_WATCH);
+
+ if (access(socket_name, W_OK) < 0) {
+ if (arg_action == ACTION_QUERY)
+ log_info("Not querying '%s' (PID %u), lacking privileges.", message, pid);
+
+ return 0;
+ }
+
+ 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;
+
+ if (arg_console) {
+ tty_fd = acquire_terminal("/dev/console", false, false, false, USEC_INFINITY);
+ if (tty_fd < 0)
+ 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, NULL, not_after, echo ? ASK_PASSWORD_ECHO : 0, filename, &password);
+
+ if (arg_console) {
+ tty_fd = safe_close(tty_fd);
+ release_terminal();
+ }
+
+ 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))
+ return 0;
+
+ if (r < 0)
+ return log_error_errno(r, "Failed to query password: %m");
+
+ r = send_passwords(socket_name, passwords);
+ if (r < 0)
+ return log_error_errno(r, "Failed to send: %m");
+ }
+
+ return 0;
+}
+
+static int wall_tty_block(void) {
+ _cleanup_free_ char *p = NULL;
+ 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 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 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 log_debug_errno(errno, "Failed to open %s: %m", p);
+
+ return fd;
+}
+
+static bool wall_tty_match(const char *path, void *userdata) {
+ _cleanup_free_ char *p = NULL;
+ _cleanup_close_ int fd = -1;
+ struct stat st;
+
+ if (!path_is_absolute(path))
+ path = strjoina("/dev/", path);
+
+ if (lstat(path, &st) < 0) {
+ log_debug_errno(errno, "Failed to stat %s: %m", path);
+ return true;
+ }
+
+ 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
+ * already shown. We use the fact here that opening a pipe in
+ * non-blocking mode for write-only will succeed only if
+ * there's some writer behind it. Using pipes has the
+ * 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) {
+ log_oom();
+ return true;
+ }
+
+ fd = open(p, O_WRONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
+ 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. */
+ return 0;
+}
+
+static int show_passwords(void) {
+ _cleanup_closedir_ DIR *d;
+ struct dirent *de;
+ int r = 0;
+
+ d = opendir("/run/systemd/ask-password");
+ if (!d) {
+ if (errno == ENOENT)
+ return 0;
+
+ return log_error_errno(errno, "Failed to open /run/systemd/ask-password: %m");
+ }
+
+ FOREACH_DIRENT_ALL(de, d, return log_error_errno(errno, "Failed to read directory: %m")) {
+ _cleanup_free_ char *p = NULL, *wall = NULL;
+ int q;
+
+ /* We only support /dev on tmpfs, hence we can rely on
+ * d_type to be reliable */
+
+ if (de->d_type != DT_REG)
+ continue;
+
+ if (hidden_file(de->d_name))
+ continue;
+
+ if (!startswith(de->d_name, "ask."))
+ continue;
+
+ p = strappend("/run/systemd/ask-password/", de->d_name);
+ if (!p)
+ return log_oom();
+
+ q = parse_password(p, &wall);
+ if (q < 0 && r == 0)
+ r = q;
+
+ if (wall)
+ (void) utmp_wall(wall, NULL, NULL, wall_tty_match, NULL);
+ }
+
+ return r;
+}
+
+static int watch_passwords(void) {
+ enum {
+ FD_INOTIFY,
+ FD_SIGNAL,
+ _FD_MAX
+ };
+
+ _cleanup_close_ int notify = -1, signal_fd = -1, tty_block_fd = -1;
+ struct pollfd pollfd[_FD_MAX] = {};
+ sigset_t mask;
+ int r;
+
+ tty_block_fd = wall_tty_block();
+
+ (void) mkdir_p_label("/run/systemd/ask-password", 0755);
+
+ notify = inotify_init1(IN_CLOEXEC);
+ if (notify < 0)
+ 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 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);
+ assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) >= 0);
+
+ signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
+ if (signal_fd < 0)
+ return log_error_errno(errno, "Failed to allocate signal file descriptor: %m");
+
+ pollfd[FD_INOTIFY].fd = notify;
+ pollfd[FD_INOTIFY].events = POLLIN;
+ pollfd[FD_SIGNAL].fd = signal_fd;
+ pollfd[FD_SIGNAL].events = POLLIN;
+
+ for (;;) {
+ r = show_passwords();
+ if (r < 0)
+ log_error_errno(r, "Failed to show password: %m");
+
+ if (poll(pollfd, _FD_MAX, -1) < 0) {
+ if (errno == EINTR)
+ continue;
+
+ return -errno;
+ }
+
+ if (pollfd[FD_INOTIFY].revents != 0)
+ (void) flush_fd(notify);
+
+ if (pollfd[FD_SIGNAL].revents != 0)
+ break;
+ }
+
+ return 0;
+}
+
+static void help(void) {
+ printf("%s [OPTIONS...]\n\n"
+ "Process system password requests.\n\n"
+ " -h --help Show this help\n"
+ " --version Show package version\n"
+ " --list Show pending password requests\n"
+ " --query Process pending password requests\n"
+ " --watch Continuously process password requests\n"
+ " --wall Continuously forward password requests to wall\n"
+ " --plymouth Ask question with Plymouth instead of on TTY\n"
+ " --console Ask question on /dev/console instead of current TTY\n",
+ program_invocation_short_name);
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+ enum {
+ ARG_LIST = 0x100,
+ ARG_QUERY,
+ ARG_WATCH,
+ ARG_WALL,
+ ARG_PLYMOUTH,
+ ARG_CONSOLE,
+ ARG_VERSION
+ };
+
+ 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 },
+ {}
+ };
+
+ int c;
+
+ assert(argc >= 0);
+ assert(argv);
+
+ while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
+
+ switch (c) {
+
+ case 'h':
+ help();
+ return 0;
+
+ case ARG_VERSION:
+ return version();
+
+ case ARG_LIST:
+ arg_action = ACTION_LIST;
+ break;
+
+ case ARG_QUERY:
+ arg_action = ACTION_QUERY;
+ break;
+
+ case ARG_WATCH:
+ arg_action = ACTION_WATCH;
+ break;
+
+ case ARG_WALL:
+ arg_action = ACTION_WALL;
+ break;
+
+ case ARG_PLYMOUTH:
+ arg_plymouth = true;
+ break;
+
+ case ARG_CONSOLE:
+ arg_console = true;
+ break;
+
+ case '?':
+ return -EINVAL;
+
+ default:
+ assert_not_reached("Unhandled option");
+ }
+
+ if (optind != argc) {
+ log_error("%s takes no arguments.", program_invocation_short_name);
+ return -EINVAL;
+ }
+
+ return 1;
+}
+
+int main(int argc, char *argv[]) {
+ int r;
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ r = parse_argv(argc, argv);
+ if (r <= 0)
+ goto finish;
+
+ if (arg_console) {
+ (void) setsid();
+ (void) release_terminal();
+ }
+
+ if (IN_SET(arg_action, ACTION_WATCH, ACTION_WALL))
+ r = watch_passwords();
+ else
+ r = show_passwords();
+
+finish:
+ return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-06 16:03:08 +0000