Systemd/src/login/sd-login.c

795 lines
18 KiB
C

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2011 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 <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/inotify.h>
#include "util.h"
#include "cgroup-util.h"
#include "macro.h"
#include "sd-login.h"
#include "strv.h"
_public_ int sd_pid_get_session(pid_t pid, char **session) {
int r;
char *cgroup, *p;
if (pid < 0)
return -EINVAL;
if (!session)
return -EINVAL;
r = cg_pid_get_cgroup(pid, NULL, &cgroup);
if (r < 0)
return r;
if (!startswith(cgroup, "/user/")) {
free(cgroup);
return -ENOENT;
}
p = strchr(cgroup + 6, '/');
if (!p) {
free(cgroup);
return -ENOENT;
}
p++;
if (startswith(p, "shared/") || streq(p, "shared")) {
free(cgroup);
return -ENOENT;
}
p = strndup(p, strcspn(p, "/"));
free(cgroup);
if (!p)
return -ENOMEM;
*session = p;
return 0;
}
_public_ int sd_pid_get_unit(pid_t pid, char **unit) {
if (pid < 0)
return -EINVAL;
if (!unit)
return -EINVAL;
return cg_pid_get_unit(pid, unit);
}
_public_ int sd_pid_get_owner_uid(pid_t pid, uid_t *uid) {
int r;
char *root, *cgroup, *p, *cc;
struct stat st;
if (pid < 0)
return -EINVAL;
if (!uid)
return -EINVAL;
r = cg_pid_get_cgroup(pid, &root, &cgroup);
if (r < 0)
return r;
if (!startswith(cgroup, "/user/")) {
free(cgroup);
free(root);
return -ENOENT;
}
p = strchr(cgroup + 6, '/');
if (!p) {
free(cgroup);
return -ENOENT;
}
p++;
p += strcspn(p, "/");
*p = 0;
r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, root, cgroup, &cc);
free(root);
free(cgroup);
if (r < 0)
return -ENOMEM;
r = lstat(cc, &st);
free(cc);
if (r < 0)
return -errno;
if (!S_ISDIR(st.st_mode))
return -ENOTDIR;
*uid = st.st_uid;
return 0;
}
_public_ int sd_uid_get_state(uid_t uid, char**state) {
char *p, *s = NULL;
int r;
if (!state)
return -EINVAL;
if (asprintf(&p, "/run/systemd/users/%lu", (unsigned long) uid) < 0)
return -ENOMEM;
r = parse_env_file(p, NEWLINE, "STATE", &s, NULL);
free(p);
if (r == -ENOENT) {
free(s);
s = strdup("offline");
if (!s)
return -ENOMEM;
*state = s;
return 0;
} else if (r < 0) {
free(s);
return r;
} else if (!s)
return -EIO;
*state = s;
return 0;
}
_public_ int sd_uid_is_on_seat(uid_t uid, int require_active, const char *seat) {
char *p, *w, *t, *state, *s = NULL;
size_t l;
int r;
const char *variable;
if (!seat)
return -EINVAL;
variable = require_active ? "ACTIVE_UID" : "UIDS";
p = strappend("/run/systemd/seats/", seat);
if (!p)
return -ENOMEM;
r = parse_env_file(p, NEWLINE, variable, &s, NULL);
free(p);
if (r < 0) {
free(s);
return r;
}
if (!s)
return -EIO;
if (asprintf(&t, "%lu", (unsigned long) uid) < 0) {
free(s);
return -ENOMEM;
}
FOREACH_WORD(w, l, s, state) {
if (strncmp(t, w, l) == 0) {
free(s);
free(t);
return 1;
}
}
free(s);
free(t);
return 0;
}
static int uid_get_array(uid_t uid, const char *variable, char ***array) {
char *p, *s = NULL;
char **a;
int r;
if (asprintf(&p, "/run/systemd/users/%lu", (unsigned long) uid) < 0)
return -ENOMEM;
r = parse_env_file(p, NEWLINE,
variable, &s,
NULL);
free(p);
if (r < 0) {
free(s);
if (r == -ENOENT) {
if (array)
*array = NULL;
return 0;
}
return r;
}
if (!s) {
if (array)
*array = NULL;
return 0;
}
a = strv_split(s, " ");
free(s);
if (!a)
return -ENOMEM;
strv_uniq(a);
r = strv_length(a);
if (array)
*array = a;
else
strv_free(a);
return r;
}
_public_ int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions) {
return uid_get_array(
uid,
require_active == 0 ? "ONLINE_SESSIONS" :
require_active > 0 ? "ACTIVE_SESSIONS" :
"SESSIONS",
sessions);
}
_public_ int sd_uid_get_seats(uid_t uid, int require_active, char ***seats) {
return uid_get_array(
uid,
require_active == 0 ? "ONLINE_SEATS" :
require_active > 0 ? "ACTIVE_SEATS" :
"SEATS",
seats);
}
static int file_of_session(const char *session, char **_p) {
char *p;
int r;
assert(_p);
if (session)
p = strappend("/run/systemd/sessions/", session);
else {
char *buf;
r = sd_pid_get_session(0, &buf);
if (r < 0)
return r;
p = strappend("/run/systemd/sessions/", buf);
free(buf);
}
if (!p)
return -ENOMEM;
*_p = p;
return 0;
}
_public_ int sd_session_is_active(const char *session) {
int r;
char *p, *s = NULL;
r = file_of_session(session, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE, "ACTIVE", &s, NULL);
free(p);
if (r < 0) {
free(s);
return r;
}
if (!s)
return -EIO;
r = parse_boolean(s);
free(s);
return r;
}
_public_ int sd_session_get_state(const char *session, char **state) {
char *p, *s = NULL;
int r;
if (!state)
return -EINVAL;
r = file_of_session(session, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE, "STATE", &s, NULL);
free(p);
if (r < 0) {
free(s);
return r;
} else if (!s)
return -EIO;
*state = s;
return 0;
}
_public_ int sd_session_get_uid(const char *session, uid_t *uid) {
int r;
char *p, *s = NULL;
if (!uid)
return -EINVAL;
r = file_of_session(session, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE, "UID", &s, NULL);
free(p);
if (r < 0) {
free(s);
return r;
}
if (!s)
return -EIO;
r = parse_uid(s, uid);
free(s);
return r;
}
static int session_get_string(const char *session, const char *field, char **value) {
char *p, *s = NULL;
int r;
if (!value)
return -EINVAL;
r = file_of_session(session, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE, field, &s, NULL);
free(p);
if (r < 0) {
free(s);
return r;
}
if (isempty(s))
return -ENOENT;
*value = s;
return 0;
}
_public_ int sd_session_get_seat(const char *session, char **seat) {
return session_get_string(session, "SEAT", seat);
}
_public_ int sd_session_get_service(const char *session, char **service) {
return session_get_string(session, "SERVICE", service);
}
_public_ int sd_session_get_type(const char *session, char **type) {
return session_get_string(session, "TYPE", type);
}
_public_ int sd_session_get_class(const char *session, char **class) {
return session_get_string(session, "CLASS", class);
}
_public_ int sd_session_get_display(const char *session, char **display) {
return session_get_string(session, "DISPLAY", display);
}
static int file_of_seat(const char *seat, char **_p) {
char *p;
int r;
assert(_p);
if (seat)
p = strappend("/run/systemd/seats/", seat);
else {
char *buf;
r = sd_session_get_seat(NULL, &buf);
if (r < 0)
return r;
p = strappend("/run/systemd/seats/", buf);
free(buf);
}
if (!p)
return -ENOMEM;
*_p = p;
return 0;
}
_public_ int sd_seat_get_active(const char *seat, char **session, uid_t *uid) {
char *p, *s = NULL, *t = NULL;
int r;
if (!session && !uid)
return -EINVAL;
r = file_of_seat(seat, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE,
"ACTIVE", &s,
"ACTIVE_UID", &t,
NULL);
free(p);
if (r < 0) {
free(s);
free(t);
return r;
}
if (session && !s) {
free(t);
return -ENOENT;
}
if (uid && !t) {
free(s);
return -ENOENT;
}
if (uid && t) {
r = parse_uid(t, uid);
if (r < 0) {
free(t);
free(s);
return r;
}
}
free(t);
if (session && s)
*session = s;
else
free(s);
return 0;
}
_public_ int sd_seat_get_sessions(const char *seat, char ***sessions, uid_t **uids, unsigned *n_uids) {
char *p, *s = NULL, *t = NULL, **a = NULL;
uid_t *b = NULL;
unsigned n = 0;
int r;
r = file_of_seat(seat, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE,
"SESSIONS", &s,
"ACTIVE_SESSIONS", &t,
NULL);
free(p);
if (r < 0) {
free(s);
free(t);
return r;
}
if (s) {
a = strv_split(s, " ");
if (!a) {
free(s);
free(t);
return -ENOMEM;
}
}
free(s);
if (uids && t) {
char *w, *state;
size_t l;
FOREACH_WORD(w, l, t, state)
n++;
if (n == 0)
b = NULL;
else {
unsigned i = 0;
b = new(uid_t, n);
if (!b) {
strv_free(a);
return -ENOMEM;
}
FOREACH_WORD(w, l, t, state) {
char *k;
k = strndup(w, l);
if (!k) {
free(t);
free(b);
strv_free(a);
return -ENOMEM;
}
r = parse_uid(k, b + i);
free(k);
if (r < 0)
continue;
i++;
}
}
}
free(t);
r = strv_length(a);
if (sessions)
*sessions = a;
else
strv_free(a);
if (uids)
*uids = b;
if (n_uids)
*n_uids = n;
return r;
}
static int seat_get_can(const char *seat, const char *variable) {
char *p, *s = NULL;
int r;
r = file_of_seat(seat, &p);
if (r < 0)
return r;
r = parse_env_file(p, NEWLINE,
variable, &s,
NULL);
free(p);
if (r < 0) {
free(s);
return r;
}
if (s) {
r = parse_boolean(s);
free(s);
} else
r = 0;
return r;
}
_public_ int sd_seat_can_multi_session(const char *seat) {
return seat_get_can(seat, "CAN_MULTI_SESSION");
}
_public_ int sd_seat_can_tty(const char *seat) {
return seat_get_can(seat, "CAN_TTY");
}
_public_ int sd_seat_can_graphical(const char *seat) {
return seat_get_can(seat, "CAN_GRAPHICAL");
}
_public_ int sd_get_seats(char ***seats) {
return get_files_in_directory("/run/systemd/seats/", seats);
}
_public_ int sd_get_sessions(char ***sessions) {
return get_files_in_directory("/run/systemd/sessions/", sessions);
}
_public_ int sd_get_uids(uid_t **users) {
DIR *d;
int r = 0;
unsigned n = 0;
uid_t *l = NULL;
d = opendir("/run/systemd/users/");
if (!d)
return -errno;
for (;;) {
struct dirent *de;
union dirent_storage buf;
int k;
uid_t uid;
k = readdir_r(d, &buf.de, &de);
if (k != 0) {
r = -k;
goto finish;
}
if (!de)
break;
dirent_ensure_type(d, de);
if (!dirent_is_file(de))
continue;
k = parse_uid(de->d_name, &uid);
if (k < 0)
continue;
if (users) {
if ((unsigned) r >= n) {
uid_t *t;
n = MAX(16, 2*r);
t = realloc(l, sizeof(uid_t) * n);
if (!t) {
r = -ENOMEM;
goto finish;
}
l = t;
}
assert((unsigned) r < n);
l[r++] = uid;
} else
r++;
}
finish:
if (d)
closedir(d);
if (r >= 0) {
if (users)
*users = l;
} else
free(l);
return r;
}
static inline int MONITOR_TO_FD(sd_login_monitor *m) {
return (int) (unsigned long) m - 1;
}
static inline sd_login_monitor* FD_TO_MONITOR(int fd) {
return (sd_login_monitor*) (unsigned long) (fd + 1);
}
_public_ int sd_login_monitor_new(const char *category, sd_login_monitor **m) {
int fd, k;
bool good = false;
if (!m)
return -EINVAL;
fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
if (fd < 0)
return errno;
if (!category || streq(category, "seat")) {
k = inotify_add_watch(fd, "/run/systemd/seats/", IN_MOVED_TO|IN_DELETE);
if (k < 0) {
close_nointr_nofail(fd);
return -errno;
}
good = true;
}
if (!category || streq(category, "session")) {
k = inotify_add_watch(fd, "/run/systemd/sessions/", IN_MOVED_TO|IN_DELETE);
if (k < 0) {
close_nointr_nofail(fd);
return -errno;
}
good = true;
}
if (!category || streq(category, "uid")) {
k = inotify_add_watch(fd, "/run/systemd/users/", IN_MOVED_TO|IN_DELETE);
if (k < 0) {
close_nointr_nofail(fd);
return -errno;
}
good = true;
}
if (!good) {
close_nointr(fd);
return -EINVAL;
}
*m = FD_TO_MONITOR(fd);
return 0;
}
_public_ sd_login_monitor* sd_login_monitor_unref(sd_login_monitor *m) {
int fd;
if (!m)
return NULL;
fd = MONITOR_TO_FD(m);
close_nointr(fd);
return NULL;
}
_public_ int sd_login_monitor_flush(sd_login_monitor *m) {
if (!m)
return -EINVAL;
return flush_fd(MONITOR_TO_FD(m));
}
_public_ int sd_login_monitor_get_fd(sd_login_monitor *m) {
if (!m)
return -EINVAL;
return MONITOR_TO_FD(m);
}