1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <sys/socket.h>
24 #include <sys/types.h>
32 #include <sys/signalfd.h>
42 static const char *arg_icon
= NULL
;
43 static const char *arg_message
= NULL
;
44 static bool arg_use_tty
= true;
45 static usec_t arg_timeout
= 60 * USEC_PER_SEC
;
47 static int create_socket(char **name
) {
51 struct sockaddr_un un
;
58 if ((fd
= socket(AF_UNIX
, SOCK_DGRAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0)) < 0) {
59 log_error("socket() failed: %m");
64 sa
.un
.sun_family
= AF_UNIX
;
65 snprintf(sa
.un
.sun_path
, sizeof(sa
.un
.sun_path
)-1, "/dev/.systemd/ask-password/sck.%llu", random_ull());
67 if (bind(fd
, &sa
.sa
, offsetof(struct sockaddr_un
, sun_path
) + strlen(sa
.un
.sun_path
)) < 0) {
69 log_error("bind() failed: %m");
73 if (setsockopt(fd
, SOL_SOCKET
, SO_PASSCRED
, &one
, sizeof(one
)) < 0) {
75 log_error("SO_PASSCRED failed: %m");
79 if (!(c
= strdup(sa
.un
.sun_path
))) {
81 log_error("Out of memory");
89 close_nointr_nofail(fd
);
94 static int help(void) {
96 printf("%s [OPTIONS...] MESSAGE\n\n"
97 "Query the user for a system passphrase, via the TTY or an UI agent.\n\n"
98 " -h --help Show this help\n"
99 " --icon=NAME Icon name\n"
100 " --timeout=SEC Timeout in sec\n"
101 " --no-tty Ask question via agent even on TTY\n",
102 program_invocation_short_name
);
107 static int parse_argv(int argc
, char *argv
[]) {
115 static const struct option options
[] = {
116 { "help", no_argument
, NULL
, 'h' },
117 { "icon", required_argument
, NULL
, ARG_ICON
},
118 { "timeout", required_argument
, NULL
, ARG_TIMEOUT
},
119 { "no-tty", no_argument
, NULL
, ARG_NO_TTY
},
128 while ((c
= getopt_long(argc
, argv
, "h", options
, NULL
)) >= 0) {
141 if (parse_usec(optarg
, &arg_timeout
) < 0 || arg_timeout
<= 0) {
142 log_error("Failed to parse --timeout parameter %s", optarg
);
155 log_error("Unknown option code %c", c
);
160 if (optind
!= argc
-1) {
165 arg_message
= argv
[optind
];
169 static int ask_agent(void) {
176 char temp
[] = "/dev/.systemd/ask-password/tmp.XXXXXX";
177 char final
[sizeof(temp
)] = "";
180 char *socket_name
= NULL
;
181 int socket_fd
= -1, signal_fd
= -1;
184 struct pollfd pollfd
[_FD_MAX
];
186 mkdir_p("/dev/.systemd/ask-password", 0755);
188 if ((fd
= mkostemp(temp
, O_CLOEXEC
|O_CREAT
|O_WRONLY
)) < 0) {
189 log_error("Failed to create password file: %m");
196 if (!(f
= fdopen(fd
, "w"))) {
197 log_error("Failed to allocate FILE: %m");
204 assert_se(sigemptyset(&mask
) == 0);
205 sigset_add_many(&mask
, SIGINT
, SIGTERM
, -1);
206 assert_se(sigprocmask(SIG_SETMASK
, &mask
, NULL
) == 0);
208 if ((signal_fd
= signalfd(-1, &mask
, SFD_NONBLOCK
|SFD_CLOEXEC
)) < 0) {
209 log_error("signalfd(): %m");
214 if ((socket_fd
= create_socket(&socket_name
)) < 0) {
219 not_after
= now(CLOCK_MONOTONIC
) + arg_timeout
;
226 (unsigned long) getpid(),
228 (unsigned long long) not_after
);
231 fprintf(f
, "Message=%s\n", arg_message
);
234 fprintf(f
, "Icon=%s\n", arg_icon
);
239 log_error("Failed to write query file: %m");
244 memcpy(final
, temp
, sizeof(temp
));
246 final
[sizeof(final
)-11] = 'a';
247 final
[sizeof(final
)-10] = 's';
248 final
[sizeof(final
)-9] = 'k';
250 if (rename(temp
, final
) < 0) {
251 log_error("Failed to rename query file: %m");
257 pollfd
[FD_SOCKET
].fd
= socket_fd
;
258 pollfd
[FD_SOCKET
].events
= POLLIN
;
259 pollfd
[FD_SIGNAL
].fd
= signal_fd
;
260 pollfd
[FD_SIGNAL
].events
= POLLIN
;
263 char passphrase
[LINE_MAX
+1];
264 struct msghdr msghdr
;
268 struct cmsghdr cmsghdr
;
269 uint8_t buf
[CMSG_SPACE(sizeof(struct ucred
))];
274 if ((k
= poll(pollfd
, _FD_MAX
, arg_timeout
/USEC_PER_MSEC
)) < 0) {
279 log_error("poll() failed: %m");
285 log_notice("Timed out");
290 if (pollfd
[FD_SIGNAL
].revents
& POLLIN
)
293 if (pollfd
[FD_SOCKET
].revents
!= POLLIN
) {
294 log_error("Unexpected poll() event.");
300 iovec
.iov_base
= passphrase
;
301 iovec
.iov_len
= sizeof(passphrase
)-1;
305 msghdr
.msg_iov
= &iovec
;
306 msghdr
.msg_iovlen
= 1;
307 msghdr
.msg_control
= &control
;
308 msghdr
.msg_controllen
= sizeof(control
);
310 if ((n
= recvmsg(socket_fd
, &msghdr
, 0)) < 0) {
312 if (errno
== EAGAIN
||
316 log_error("recvmsg() failed: %m");
322 log_error("Message too short");
326 if (msghdr
.msg_controllen
< CMSG_LEN(sizeof(struct ucred
)) ||
327 control
.cmsghdr
.cmsg_level
!= SOL_SOCKET
||
328 control
.cmsghdr
.cmsg_type
!= SCM_CREDENTIALS
||
329 control
.cmsghdr
.cmsg_len
!= CMSG_LEN(sizeof(struct ucred
))) {
330 log_warning("Received message without credentials. Ignoring.");
334 ucred
= (struct ucred
*) CMSG_DATA(&control
.cmsghdr
);
335 if (ucred
->uid
!= 0) {
336 log_warning("Got request from unprivileged user. Ignoring.");
340 if (passphrase
[0] == '+') {
342 fputs(passphrase
+1, stdout
);
344 } else if (passphrase
[0] == '-') {
348 log_error("Invalid packet");
359 close_nointr_nofail(fd
);
367 close_nointr_nofail(socket_fd
);
370 close_nointr_nofail(signal_fd
);
383 int main(int argc
, char *argv
[]) {
386 log_parse_environment();
389 if ((r
= parse_argv(argc
, argv
)) <= 0)
392 if (arg_use_tty
&& isatty(STDIN_FILENO
)) {
393 char *password
= NULL
;
395 if ((r
= ask_password_tty(arg_message
, now(CLOCK_MONOTONIC
) + arg_timeout
, NULL
, &password
)) >= 0) {
396 fputs(password
, stdout
);
405 return r
< 0 ? EXIT_FAILURE
: EXIT_SUCCESS
;