[thirdparty/systemd.git] / src / ask-password-api.c

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  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 General Public License as published by
  the Free Software Foundation; either version 2 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <stdbool.h>
#include <termios.h>
#include <unistd.h>
#include <sys/poll.h>
#include <sys/inotify.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <string.h>
#include <sys/un.h>
#include <stddef.h>
#include <sys/signalfd.h>

#include "util.h"
#include "strv.h"

#include "ask-password-api.h"

static void backspace_chars(int ttyfd, size_t p) {

        if (ttyfd < 0)
                return;

        while (p > 0) {
                p--;

                loop_write(ttyfd, "\b \b", 3, false);
        }
}

int ask_password_tty(
                const char *message,
                usec_t until,
                const char *flag_file,
                char **_passphrase) {

        struct termios old_termios, new_termios;
        char passphrase[LINE_MAX];
        size_t p = 0;
        int r, ttyfd = -1, notify = -1;
        struct pollfd pollfd[2];
        bool reset_tty = false;
        bool silent_mode = false;
        bool dirty = false;
        enum {
                POLL_TTY,
                POLL_INOTIFY
        };

        assert(message);
        assert(_passphrase);

        if (flag_file) {
                if ((notify = inotify_init1(IN_CLOEXEC|IN_NONBLOCK)) < 0) {
                        r = -errno;
                        goto finish;
                }

                if (inotify_add_watch(notify, flag_file, IN_ATTRIB /* for the link count */) < 0) {
                        r = -errno;
                        goto finish;
                }
        }

        if ((ttyfd = open("/dev/tty", O_RDWR|O_NOCTTY|O_CLOEXEC)) >= 0) {

                if (tcgetattr(ttyfd, &old_termios) < 0) {
                        r = -errno;
                        goto finish;
                }

                loop_write(ttyfd, "\x1B[1m", 4, false);
                loop_write(ttyfd, message, strlen(message), false);
                loop_write(ttyfd, " ", 1, false);
                loop_write(ttyfd, "\x1B[0m", 4, false);

                new_termios = old_termios;
                new_termios.c_lflag &= ~(ICANON|ECHO);
                new_termios.c_cc[VMIN] = 1;
                new_termios.c_cc[VTIME] = 0;

                if (tcsetattr(ttyfd, TCSADRAIN, &new_termios) < 0) {
                        r = -errno;
                        goto finish;
                }

                reset_tty = true;
        }

        zero(pollfd);

        pollfd[POLL_TTY].fd = ttyfd >= 0 ? ttyfd : STDIN_FILENO;
        pollfd[POLL_TTY].events = POLLIN;
        pollfd[POLL_INOTIFY].fd = notify;
        pollfd[POLL_INOTIFY].events = POLLIN;

        for (;;) {
                char c;
                int sleep_for = -1, k;
                ssize_t n;

                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)
                        if (access(flag_file, F_OK) < 0) {
                                r = -errno;
                                goto finish;
                        }

                if ((k = poll(pollfd, notify > 0 ? 2 : 1, sleep_for)) < 0) {

                        if (errno == EINTR)
                                continue;

                        r = -errno;
                        goto finish;
                } else if (k == 0) {
                        r = -ETIME;
                        goto finish;
                }

                if (notify > 0 && pollfd[POLL_INOTIFY].revents != 0)
                        flush_fd(notify);

                if (pollfd[POLL_TTY].revents == 0)
                        continue;

                if ((n = read(ttyfd >= 0 ? ttyfd : STDIN_FILENO, &c, 1)) < 0) {

                        if (errno == EINTR || errno == EAGAIN)
                                continue;

                        r = -errno;
                        goto finish;

                } else if (n == 0)
                        break;

                if (c == '\n')
                        break;
                else if (c == 21) { /* C-u */

                        if (!silent_mode)
                                backspace_chars(ttyfd, p);
                        p = 0;

                } else if (c == '\b' || c == 127) {

                        if (p > 0) {

                                if (!silent_mode)
                                        backspace_chars(ttyfd, 1);

                                p--;
                        } else if (!dirty && !silent_mode) {

                                silent_mode = true;

                                /* There are two ways to enter silent
                                 * mode. Either by pressing backspace
                                 * as first key (and only as first key),
                                 * or ... */
                                if (ttyfd >= 0)
                                        loop_write(ttyfd, "(no echo) ", 10, false);

                        } else if (ttyfd >= 0)
                                loop_write(ttyfd, "\a", 1, false);

                } else if (c == '\t' && !silent_mode) {

                        backspace_chars(ttyfd, p);
                        silent_mode = true;

                        /* ... or by pressing TAB at any time. */

                        if (ttyfd >= 0)
                                loop_write(ttyfd, "(no echo) ", 10, false);
                } else {
                        passphrase[p++] = c;

                        if (!silent_mode && ttyfd >= 0)
                                loop_write(ttyfd, "*", 1, false);

                        dirty = true;
                }
        }

        passphrase[p] = 0;

        if (!(*_passphrase = strdup(passphrase))) {
                r = -ENOMEM;
                goto finish;
        }

        r = 0;

finish:
        if (notify >= 0)
                close_nointr_nofail(notify);

        if (ttyfd >= 0) {

                if (reset_tty) {
                        loop_write(ttyfd, "\n", 1, false);
                        tcsetattr(ttyfd, TCSADRAIN, &old_termios);
                }

                close_nointr_nofail(ttyfd);
        }

        return r;
}

static int create_socket(char **name) {
        int fd;
        union {
                struct sockaddr sa;
                struct sockaddr_un un;
        } sa;
        int one = 1, r;
        char *c;

        assert(name);

        if ((fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0)) < 0) {
                log_error("socket() failed: %m");
                return -errno;
        }

        zero(sa);
        sa.un.sun_family = AF_UNIX;
        snprintf(sa.un.sun_path, sizeof(sa.un.sun_path)-1, "/run/systemd/ask-password/sck.%llu", random_ull());

        if (bind(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
                r = -errno;
                log_error("bind() failed: %m");
                goto fail;
        }

        if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) {
                r = -errno;
                log_error("SO_PASSCRED failed: %m");
                goto fail;
        }

        if (!(c = strdup(sa.un.sun_path))) {
                r = -ENOMEM;
                log_error("Out of memory");
                goto fail;
        }

        *name = c;
        return fd;

fail:
        close_nointr_nofail(fd);

        return r;
}

int ask_password_agent(
                const char *message,
                const char *icon,
                usec_t until,
                bool accept_cached,
                char ***_passphrases) {

        enum {
                FD_SOCKET,
                FD_SIGNAL,
                _FD_MAX
        };

        char temp[] = "/run/systemd/ask-password/tmp.XXXXXX";
        char final[sizeof(temp)] = "";
        int fd = -1, r;
        FILE *f = NULL;
        char *socket_name = NULL;
        int socket_fd = -1, signal_fd = -1;
        sigset_t mask, oldmask;
        struct pollfd pollfd[_FD_MAX];

        assert(_passphrases);

        assert_se(sigemptyset(&mask) == 0);
        sigset_add_many(&mask, SIGINT, SIGTERM, -1);
        assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0);

        mkdir_p("/run/systemd/ask-password", 0755);

        if ((fd = mkostemp(temp, O_CLOEXEC|O_CREAT|O_WRONLY)) < 0) {
                log_error("Failed to create password file: %m");
                r = -errno;
                goto finish;
        }

        fchmod(fd, 0644);

        if (!(f = fdopen(fd, "w"))) {
                log_error("Failed to allocate FILE: %m");
                r = -errno;
                goto finish;
        }

        fd = -1;

        if ((signal_fd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) {
                log_error("signalfd(): %m");
                r = -errno;
                goto finish;
        }

        if ((socket_fd = create_socket(&socket_name)) < 0) {
                r = socket_fd;
                goto finish;
        }

        fprintf(f,
                "[Ask]\n"
                "PID=%lu\n"
                "Socket=%s\n"
                "AcceptCached=%i\n"
                "NotAfter=%llu\n",
                (unsigned long) getpid(),
                socket_name,
                accept_cached ? 1 : 0,
                (unsigned long long) until);

        if (message)
                fprintf(f, "Message=%s\n", message);

        if (icon)
                fprintf(f, "Icon=%s\n", icon);

        fflush(f);

        if (ferror(f)) {
                log_error("Failed to write query file: %m");
                r = -errno;
                goto finish;
        }

        memcpy(final, temp, sizeof(temp));

        final[sizeof(final)-11] = 'a';
        final[sizeof(final)-10] = 's';
        final[sizeof(final)-9] = 'k';

        if (rename(temp, final) < 0) {
                log_error("Failed to rename query file: %m");
                r = -errno;
                goto finish;
        }

        zero(pollfd);
        pollfd[FD_SOCKET].fd = socket_fd;
        pollfd[FD_SOCKET].events = POLLIN;
        pollfd[FD_SIGNAL].fd = signal_fd;
        pollfd[FD_SIGNAL].events = POLLIN;

        for (;;) {
                char passphrase[LINE_MAX+1];
                struct msghdr msghdr;
                struct iovec iovec;
                struct ucred *ucred;
                union {
                        struct cmsghdr cmsghdr;
                        uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
                } control;
                ssize_t n;
                int k;
                usec_t t;

                t = now(CLOCK_MONOTONIC);

                if (until <= t) {
                        log_notice("Timed out");
                        r = -ETIME;
                        goto finish;
                }

                if ((k = poll(pollfd, _FD_MAX, (until-t)/USEC_PER_MSEC)) < 0) {

                        if (errno == EINTR)
                                continue;

                        log_error("poll() failed: %m");
                        r = -errno;
                        goto finish;
                }

                if (k <= 0) {
                        log_notice("Timed out");
                        r = -ETIME;
                        goto finish;
                }

                if (pollfd[FD_SIGNAL].revents & POLLIN) {
                        r = -EINTR;
                        goto finish;
                }

                if (pollfd[FD_SOCKET].revents != POLLIN) {
                        log_error("Unexpected poll() event.");
                        r = -EIO;
                        goto finish;
                }

                zero(iovec);
                iovec.iov_base = passphrase;
                iovec.iov_len = sizeof(passphrase);

                zero(control);
                zero(msghdr);
                msghdr.msg_iov = &iovec;
                msghdr.msg_iovlen = 1;
                msghdr.msg_control = &control;
                msghdr.msg_controllen = sizeof(control);

                if ((n = recvmsg(socket_fd, &msghdr, 0)) < 0) {

                        if (errno == EAGAIN ||
                            errno == EINTR)
                                continue;

                        log_error("recvmsg() failed: %m");
                        r = -errno;
                        goto finish;
                }

                if (n <= 0) {
                        log_error("Message too short");
                        continue;
                }

                if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) ||
                    control.cmsghdr.cmsg_level != SOL_SOCKET ||
                    control.cmsghdr.cmsg_type != SCM_CREDENTIALS ||
                    control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
                        log_warning("Received message without credentials. Ignoring.");
                        continue;
                }

                ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
                if (ucred->uid != 0) {
                        log_warning("Got request from unprivileged user. Ignoring.");
                        continue;
                }

                if (passphrase[0] == '+') {
                        char **l;

                        if (!(l = strv_parse_nulstr(passphrase+1, n-1))) {
                                r = -ENOMEM;
                                goto finish;
                        }

                        if (strv_length(l) <= 0) {
                                strv_free(l);
                                log_error("Invalid packet");
                                continue;
                        }

                        *_passphrases = l;

                } else if (passphrase[0] == '-') {
                        r = -ECANCELED;
                        goto finish;
                } else {
                        log_error("Invalid packet");
                        continue;
                }

                break;
        }

        r = 0;

finish:
        if (fd >= 0)
                close_nointr_nofail(fd);

        if (socket_name) {
                unlink(socket_name);
                free(socket_name);
        }

        if (socket_fd >= 0)
                close_nointr_nofail(socket_fd);

        if (signal_fd >= 0)
                close_nointr_nofail(signal_fd);

        if (f)
                fclose(f);

        unlink(temp);

        if (final[0])
                unlink(final);

        assert_se(sigprocmask(SIG_SETMASK, &oldmask, NULL) == 0);

        return r;
}

int ask_password_auto(const char *message, const char *icon, usec_t until, bool accept_cached, char ***_passphrases) {
        assert(message);
        assert(_passphrases);

        if (isatty(STDIN_FILENO)) {
                int r;
                char *s = NULL, **l = NULL;

                if ((r = ask_password_tty(message, until, NULL, &s)) < 0)
                        return r;

                l = strv_new(s, NULL);
                free(s);

                if (!l)
                        return -ENOMEM;

                *_passphrases = l;
                return r;

        } else
                return ask_password_agent(message, icon, until, accept_cached, _passphrases);
}
Commit	Line	Data
7f4e0805 LP	1	/-- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil --/
	2
	3	/***
	4	This file is part of systemd.
	5
	6	Copyright 2010 Lennart Poettering
	7
	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.
	12
	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.
	17
	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/>.
	20	***/
d1676230	21	#include <stdbool.h>
7f4e0805 LP	22	#include <termios.h>
	23	#include <unistd.h>
	24	#include <sys/poll.h>
	25	#include <sys/inotify.h>
	26	#include <errno.h>
	27	#include <fcntl.h>
	28	#include <sys/socket.h>
	29	#include <string.h>
	30	#include <sys/un.h>
	31	#include <stddef.h>
	32	#include <sys/signalfd.h>
	33
	34	#include "util.h"
21bc923a	35	#include "strv.h"
7f4e0805 LP	36
	37	#include "ask-password-api.h"
	38
58fc840b LP	39	static void backspace_chars(int ttyfd, size_t p) {
	40
	41	if (ttyfd < 0)
	42	return;
	43
	44	while (p > 0) {
	45	p--;
	46
	47	loop_write(ttyfd, "\b \b", 3, false);
	48	}
	49	}
	50
7f4e0805 LP	51	int ask_password_tty(
	52	const char *message,
	53	usec_t until,
	54	const char *flag_file,
	55	char **_passphrase) {
	56
	57	struct termios old_termios, new_termios;
	58	char passphrase[LINE_MAX];
	59	size_t p = 0;
	60	int r, ttyfd = -1, notify = -1;
	61	struct pollfd pollfd[2];
	62	bool reset_tty = false;
d1676230	63	bool silent_mode = false;
441dfe09	64	bool dirty = false;
7f4e0805 LP	65	enum {
	66	POLL_TTY,
	67	POLL_INOTIFY
	68	};
	69
	70	assert(message);
	71	assert(_passphrase);
	72
	73	if (flag_file) {
	74	if ((notify = inotify_init1(IN_CLOEXEC\|IN_NONBLOCK)) < 0) {
	75	r = -errno;
	76	goto finish;
	77	}
	78
	79	if (inotify_add_watch(notify, flag_file, IN_ATTRIB /* for the link count */) < 0) {
	80	r = -errno;
	81	goto finish;
	82	}
	83	}
	84
	85	if ((ttyfd = open("/dev/tty", O_RDWR\|O_NOCTTY\|O_CLOEXEC)) >= 0) {
	86
	87	if (tcgetattr(ttyfd, &old_termios) < 0) {
	88	r = -errno;
	89	goto finish;
	90	}
	91
	92	loop_write(ttyfd, "\x1B[1m", 4, false);
	93	loop_write(ttyfd, message, strlen(message), false);
bd1db33f	94	loop_write(ttyfd, " ", 1, false);
7f4e0805 LP	95	loop_write(ttyfd, "\x1B[0m", 4, false);
	96
	97	new_termios = old_termios;
	98	new_termios.c_lflag &= ~(ICANON\|ECHO);
	99	new_termios.c_cc[VMIN] = 1;
	100	new_termios.c_cc[VTIME] = 0;
	101
	102	if (tcsetattr(ttyfd, TCSADRAIN, &new_termios) < 0) {
	103	r = -errno;
	104	goto finish;
	105	}
	106
	107	reset_tty = true;
	108	}
	109
	110	zero(pollfd);
	111
	112	pollfd[POLL_TTY].fd = ttyfd >= 0 ? ttyfd : STDIN_FILENO;
	113	pollfd[POLL_TTY].events = POLLIN;
	114	pollfd[POLL_INOTIFY].fd = notify;
	115	pollfd[POLL_INOTIFY].events = POLLIN;
	116
	117	for (;;) {
	118	char c;
	119	int sleep_for = -1, k;
	120	ssize_t n;
	121
	122	if (until > 0) {
	123	usec_t y;
	124
	125	y = now(CLOCK_MONOTONIC);
	126
	127	if (y > until) {
7ded2e28	128	r = -ETIME;
7f4e0805 LP	129	goto finish;
	130	}
	131
	132	sleep_for = (int) ((until - y) / USEC_PER_MSEC);
	133	}
	134
	135	if (flag_file)
	136	if (access(flag_file, F_OK) < 0) {
	137	r = -errno;
	138	goto finish;
	139	}
	140
	141	if ((k = poll(pollfd, notify > 0 ? 2 : 1, sleep_for)) < 0) {
	142
	143	if (errno == EINTR)
	144	continue;
	145
	146	r = -errno;
	147	goto finish;
	148	} else if (k == 0) {
ccc80078	149	r = -ETIME;
7f4e0805 LP	150	goto finish;
	151	}
	152
	153	if (notify > 0 && pollfd[POLL_INOTIFY].revents != 0)
	154	flush_fd(notify);
	155
	156	if (pollfd[POLL_TTY].revents == 0)
	157	continue;
	158
	159	if ((n = read(ttyfd >= 0 ? ttyfd : STDIN_FILENO, &c, 1)) < 0) {
	160
	161	if (errno == EINTR \|\| errno == EAGAIN)
	162	continue;
	163
	164	r = -errno;
	165	goto finish;
	166
	167	} else if (n == 0)
	168	break;
	169
	170	if (c == '\n')
	171	break;
58fc840b	172	else if (c == 21) { /* C-u */
7f4e0805	173
58fc840b LP	174	if (!silent_mode)
	175	backspace_chars(ttyfd, p);
	176	p = 0;
7f4e0805 LP	177
7f4e0805 LP	178	} else if (c == '\b' \|\| c == 127) {
58fc840b LP	179
	180	if (p > 0) {
	181
	182	if (!silent_mode)
	183	backspace_chars(ttyfd, 1);
	184
7f4e0805	185	p--;
441dfe09 LP	186	} else if (!dirty && !silent_mode) {
	187
	188	silent_mode = true;
	189
	190	/* There are two ways to enter silent
	191	* mode. Either by pressing backspace
	192	* as first key (and only as first key),
	193	* or ... */
	194	if (ttyfd >= 0)
	195	loop_write(ttyfd, "(no echo) ", 10, false);
	196
58fc840b LP	197	} else if (ttyfd >= 0)
58fc840b LP	198	loop_write(ttyfd, "\a", 1, false);
7f4e0805	199
58fc840b LP	200	} else if (c == '\t' && !silent_mode) {
	201
	202	backspace_chars(ttyfd, p);
	203	silent_mode = true;
	204
441dfe09 LP	205	/* ... or by pressing TAB at any time. */
441dfe09 LP	206
58fc840b LP	207	if (ttyfd >= 0)
58fc840b LP	208	loop_write(ttyfd, "(no echo) ", 10, false);
7f4e0805 LP	209	} else {
	210	passphrase[p++] = c;
	211
d1676230	212	if (!silent_mode && ttyfd >= 0)
7f4e0805	213	loop_write(ttyfd, "*", 1, false);
441dfe09 LP	214
441dfe09 LP	215	dirty = true;
7f4e0805 LP	216	}
	217	}
	218
7f4e0805 LP	219	passphrase[p] = 0;
	220
	221	if (!(*_passphrase = strdup(passphrase))) {
	222	r = -ENOMEM;
	223	goto finish;
	224	}
	225
	226	r = 0;
	227
	228	finish:
	229	if (notify >= 0)
	230	close_nointr_nofail(notify);
	231
	232	if (ttyfd >= 0) {
c0f9c7da LP	233
	234	if (reset_tty) {
	235	loop_write(ttyfd, "\n", 1, false);
7f4e0805	236	tcsetattr(ttyfd, TCSADRAIN, &old_termios);
c0f9c7da	237	}
7f4e0805 LP	238
	239	close_nointr_nofail(ttyfd);
	240	}
	241
	242	return r;
	243	}
	244
	245	static int create_socket(char **name) {
	246	int fd;
	247	union {
	248	struct sockaddr sa;
	249	struct sockaddr_un un;
	250	} sa;
	251	int one = 1, r;
	252	char *c;
	253
	254	assert(name);
	255
	256	if ((fd = socket(AF_UNIX, SOCK_DGRAM\|SOCK_CLOEXEC\|SOCK_NONBLOCK, 0)) < 0) {
	257	log_error("socket() failed: %m");
	258	return -errno;
	259	}
	260
	261	zero(sa);
	262	sa.un.sun_family = AF_UNIX;
2b583ce6	263	snprintf(sa.un.sun_path, sizeof(sa.un.sun_path)-1, "/run/systemd/ask-password/sck.%llu", random_ull());
7f4e0805 LP	264
	265	if (bind(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
	266	r = -errno;
	267	log_error("bind() failed: %m");
	268	goto fail;
	269	}
	270
	271	if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)) < 0) {
	272	r = -errno;
	273	log_error("SO_PASSCRED failed: %m");
	274	goto fail;
	275	}
	276
	277	if (!(c = strdup(sa.un.sun_path))) {
	278	r = -ENOMEM;
	279	log_error("Out of memory");
	280	goto fail;
	281	}
	282
	283	*name = c;
	284	return fd;
	285
	286	fail:
	287	close_nointr_nofail(fd);
	288
	289	return r;
	290	}
	291
7f4e0805 LP	292	int ask_password_agent(
	293	const char *message,
	294	const char *icon,
	295	usec_t until,
21bc923a LP	296	bool accept_cached,
21bc923a LP	297	char ***_passphrases) {
7f4e0805 LP	298
	299	enum {
	300	FD_SOCKET,
	301	FD_SIGNAL,
	302	_FD_MAX
	303	};
	304
2b583ce6	305	char temp[] = "/run/systemd/ask-password/tmp.XXXXXX";
7f4e0805 LP	306	char final[sizeof(temp)] = "";
	307	int fd = -1, r;
	308	FILE *f = NULL;
	309	char *socket_name = NULL;
	310	int socket_fd = -1, signal_fd = -1;
f9b72cd8	311	sigset_t mask, oldmask;
7f4e0805 LP	312	struct pollfd pollfd[_FD_MAX];
7f4e0805 LP	313
21bc923a LP	314	assert(_passphrases);
21bc923a LP	315
f9b72cd8 LP	316	assert_se(sigemptyset(&mask) == 0);
	317	sigset_add_many(&mask, SIGINT, SIGTERM, -1);
	318	assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0);
	319
2b583ce6	320	mkdir_p("/run/systemd/ask-password", 0755);
7f4e0805 LP	321
	322	if ((fd = mkostemp(temp, O_CLOEXEC\|O_CREAT\|O_WRONLY)) < 0) {
	323	log_error("Failed to create password file: %m");
	324	r = -errno;
	325	goto finish;
	326	}
	327
	328	fchmod(fd, 0644);
	329
	330	if (!(f = fdopen(fd, "w"))) {
	331	log_error("Failed to allocate FILE: %m");
	332	r = -errno;
	333	goto finish;
	334	}
	335
	336	fd = -1;
	337
7f4e0805 LP	338	if ((signal_fd = signalfd(-1, &mask, SFD_NONBLOCK\|SFD_CLOEXEC)) < 0) {
	339	log_error("signalfd(): %m");
	340	r = -errno;
	341	goto finish;
	342	}
	343
	344	if ((socket_fd = create_socket(&socket_name)) < 0) {
	345	r = socket_fd;
	346	goto finish;
	347	}
	348
	349	fprintf(f,
	350	"[Ask]\n"
	351	"PID=%lu\n"
	352	"Socket=%s\n"
21bc923a	353	"AcceptCached=%i\n"
7f4e0805 LP	354	"NotAfter=%llu\n",
	355	(unsigned long) getpid(),
	356	socket_name,
21bc923a	357	accept_cached ? 1 : 0,
7f4e0805 LP	358	(unsigned long long) until);
	359
	360	if (message)
	361	fprintf(f, "Message=%s\n", message);
	362
	363	if (icon)
	364	fprintf(f, "Icon=%s\n", icon);
	365
	366	fflush(f);
	367
	368	if (ferror(f)) {
	369	log_error("Failed to write query file: %m");
	370	r = -errno;
	371	goto finish;
	372	}
	373
	374	memcpy(final, temp, sizeof(temp));
	375
	376	final[sizeof(final)-11] = 'a';
	377	final[sizeof(final)-10] = 's';
	378	final[sizeof(final)-9] = 'k';
	379
	380	if (rename(temp, final) < 0) {
	381	log_error("Failed to rename query file: %m");
	382	r = -errno;
	383	goto finish;
	384	}
	385
	386	zero(pollfd);
	387	pollfd[FD_SOCKET].fd = socket_fd;
	388	pollfd[FD_SOCKET].events = POLLIN;
	389	pollfd[FD_SIGNAL].fd = signal_fd;
	390	pollfd[FD_SIGNAL].events = POLLIN;
	391
	392	for (;;) {
	393	char passphrase[LINE_MAX+1];
	394	struct msghdr msghdr;
	395	struct iovec iovec;
	396	struct ucred *ucred;
	397	union {
	398	struct cmsghdr cmsghdr;
	399	uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
	400	} control;
	401	ssize_t n;
	402	int k;
	403	usec_t t;
	404
	405	t = now(CLOCK_MONOTONIC);
	406
	407	if (until <= t) {
	408	log_notice("Timed out");
	409	r = -ETIME;
	410	goto finish;
	411	}
	412
7ded2e28	413	if ((k = poll(pollfd, _FD_MAX, (until-t)/USEC_PER_MSEC)) < 0) {
7f4e0805 LP	414
	415	if (errno == EINTR)
	416	continue;
	417
	418	log_error("poll() failed: %m");
	419	r = -errno;
	420	goto finish;
	421	}
	422
	423	if (k <= 0) {
	424	log_notice("Timed out");
	425	r = -ETIME;
	426	goto finish;
	427	}
	428
21bc923a LP	429	if (pollfd[FD_SIGNAL].revents & POLLIN) {
	430	r = -EINTR;
	431	goto finish;
	432	}
7f4e0805 LP	433
	434	if (pollfd[FD_SOCKET].revents != POLLIN) {
	435	log_error("Unexpected poll() event.");
	436	r = -EIO;
	437	goto finish;
	438	}
	439
	440	zero(iovec);
	441	iovec.iov_base = passphrase;
21bc923a	442	iovec.iov_len = sizeof(passphrase);
7f4e0805 LP	443
	444	zero(control);
	445	zero(msghdr);
	446	msghdr.msg_iov = &iovec;
	447	msghdr.msg_iovlen = 1;
	448	msghdr.msg_control = &control;
	449	msghdr.msg_controllen = sizeof(control);
	450
	451	if ((n = recvmsg(socket_fd, &msghdr, 0)) < 0) {
	452
	453	if (errno == EAGAIN \|\|
	454	errno == EINTR)
	455	continue;
	456
	457	log_error("recvmsg() failed: %m");
	458	r = -errno;
	459	goto finish;
	460	}
	461
	462	if (n <= 0) {
	463	log_error("Message too short");
	464	continue;
	465	}
	466
	467	if (msghdr.msg_controllen < CMSG_LEN(sizeof(struct ucred)) \|\|
	468	control.cmsghdr.cmsg_level != SOL_SOCKET \|\|
	469	control.cmsghdr.cmsg_type != SCM_CREDENTIALS \|\|
	470	control.cmsghdr.cmsg_len != CMSG_LEN(sizeof(struct ucred))) {
	471	log_warning("Received message without credentials. Ignoring.");
	472	continue;
	473	}
	474
	475	ucred = (struct ucred*) CMSG_DATA(&control.cmsghdr);
	476	if (ucred->uid != 0) {
	477	log_warning("Got request from unprivileged user. Ignoring.");
	478	continue;
	479	}
	480
	481	if (passphrase[0] == '+') {
21bc923a	482	char **l;
7f4e0805	483
21bc923a	484	if (!(l = strv_parse_nulstr(passphrase+1, n-1))) {
7f4e0805 LP	485	r = -ENOMEM;
	486	goto finish;
	487	}
	488
21bc923a LP	489	if (strv_length(l) <= 0) {
	490	strv_free(l);
	491	log_error("Invalid packet");
	492	continue;
	493	}
	494
	495	*_passphrases = l;
	496
7f4e0805 LP	497	} else if (passphrase[0] == '-') {
	498	r = -ECANCELED;
	499	goto finish;
	500	} else {
	501	log_error("Invalid packet");
	502	continue;
	503	}
	504
	505	break;
	506	}
	507
	508	r = 0;
	509
	510	finish:
	511	if (fd >= 0)
	512	close_nointr_nofail(fd);
	513
	514	if (socket_name) {
	515	unlink(socket_name);
	516	free(socket_name);
	517	}
	518
	519	if (socket_fd >= 0)
	520	close_nointr_nofail(socket_fd);
	521
	522	if (signal_fd >= 0)
	523	close_nointr_nofail(signal_fd);
	524
	525	if (f)
	526	fclose(f);
	527
	528	unlink(temp);
	529
	530	if (final[0])
	531	unlink(final);
	532
f9b72cd8 LP	533	assert_se(sigprocmask(SIG_SETMASK, &oldmask, NULL) == 0);
f9b72cd8 LP	534
7f4e0805 LP	535	return r;
7f4e0805 LP	536	}
260ab287	537
21bc923a	538	int ask_password_auto(const char message, const char icon, usec_t until, bool accept_cached, char ***_passphrases) {
260ab287	539	assert(message);
21bc923a LP	540	assert(_passphrases);
	541
	542	if (isatty(STDIN_FILENO)) {
	543	int r;
	544	char s = NULL, *l = NULL;
	545
	546	if ((r = ask_password_tty(message, until, NULL, &s)) < 0)
	547	return r;
	548
	549	l = strv_new(s, NULL);
	550	free(s);
	551
	552	if (!l)
	553	return -ENOMEM;
	554
	555	*_passphrases = l;
	556	return r;
260ab287	557
21bc923a LP	558	} else
21bc923a LP	559	return ask_password_agent(message, icon, until, accept_cached, _passphrases);
260ab287	560	}