Systemd/src/login/logind-user.c

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/*-*- 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 <sys/mount.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include "util.h"
#include "mkdir.h"
#include "rm-rf.h"
#include "hashmap.h"
#include "fileio.h"
#include "path-util.h"
#include "special.h"
#include "unit-name.h"
#include "bus-util.h"
#include "bus-error.h"
#include "conf-parser.h"
#include "clean-ipc.h"
#include "smack-util.h"
#include "formats-util.h"
#include "label.h"
#include "logind-user.h"
User* user_new(Manager *m, uid_t uid, gid_t gid, const char *name) {
User *u;
assert(m);
assert(name);
u = new0(User, 1);
if (!u)
return NULL;
u->name = strdup(name);
if (!u->name)
goto fail;
if (asprintf(&u->state_file, "/run/systemd/users/"UID_FMT, uid) < 0)
goto fail;
if (hashmap_put(m->users, UID_TO_PTR(uid), u) < 0)
goto fail;
u->manager = m;
u->uid = uid;
u->gid = gid;
return u;
fail:
free(u->state_file);
free(u->name);
free(u);
return NULL;
}
void user_free(User *u) {
assert(u);
if (u->in_gc_queue)
LIST_REMOVE(gc_queue, u->manager->user_gc_queue, u);
while (u->sessions)
session_free(u->sessions);
if (u->slice) {
hashmap_remove(u->manager->user_units, u->slice);
free(u->slice);
}
if (u->service) {
hashmap_remove(u->manager->user_units, u->service);
free(u->service);
}
free(u->slice_job);
free(u->service_job);
free(u->runtime_path);
hashmap_remove(u->manager->users, UID_TO_PTR(u->uid));
free(u->name);
free(u->state_file);
free(u);
}
static int user_save_internal(User *u) {
_cleanup_free_ char *temp_path = NULL;
_cleanup_fclose_ FILE *f = NULL;
int r;
assert(u);
assert(u->state_file);
r = mkdir_safe_label("/run/systemd/users", 0755, 0, 0);
if (r < 0)
goto fail;
r = fopen_temporary(u->state_file, &f, &temp_path);
if (r < 0)
goto fail;
fchmod(fileno(f), 0644);
fprintf(f,
"# This is private data. Do not parse.\n"
"NAME=%s\n"
"STATE=%s\n",
u->name,
user_state_to_string(user_get_state(u)));
if (u->runtime_path)
fprintf(f, "RUNTIME=%s\n", u->runtime_path);
if (u->service)
fprintf(f, "SERVICE=%s\n", u->service);
if (u->service_job)
fprintf(f, "SERVICE_JOB=%s\n", u->service_job);
if (u->slice)
fprintf(f, "SLICE=%s\n", u->slice);
if (u->slice_job)
fprintf(f, "SLICE_JOB=%s\n", u->slice_job);
if (u->display)
fprintf(f, "DISPLAY=%s\n", u->display->id);
if (dual_timestamp_is_set(&u->timestamp))
fprintf(f,
"REALTIME="USEC_FMT"\n"
"MONOTONIC="USEC_FMT"\n",
u->timestamp.realtime,
u->timestamp.monotonic);
if (u->sessions) {
Session *i;
bool first;
fputs("SESSIONS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (first)
first = false;
else
fputc(' ', f);
fputs(i->id, f);
}
fputs("\nSEATS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (!i->seat)
continue;
if (first)
first = false;
else
fputc(' ', f);
fputs(i->seat->id, f);
}
fputs("\nACTIVE_SESSIONS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (!session_is_active(i))
continue;
if (first)
first = false;
else
fputc(' ', f);
fputs(i->id, f);
}
fputs("\nONLINE_SESSIONS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (session_get_state(i) == SESSION_CLOSING)
continue;
if (first)
first = false;
else
fputc(' ', f);
fputs(i->id, f);
}
fputs("\nACTIVE_SEATS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (!session_is_active(i) || !i->seat)
continue;
if (first)
first = false;
else
fputc(' ', f);
fputs(i->seat->id, f);
}
fputs("\nONLINE_SEATS=", f);
first = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
if (session_get_state(i) == SESSION_CLOSING || !i->seat)
continue;
if (first)
first = false;
else
fputc(' ', f);
fputs(i->seat->id, f);
}
fputc('\n', f);
}
r = fflush_and_check(f);
if (r < 0)
goto fail;
if (rename(temp_path, u->state_file) < 0) {
r = -errno;
goto fail;
}
return 0;
fail:
(void) unlink(u->state_file);
if (temp_path)
(void) unlink(temp_path);
return log_error_errno(r, "Failed to save user data %s: %m", u->state_file);
}
int user_save(User *u) {
assert(u);
if (!u->started)
return 0;
return user_save_internal (u);
}
int user_load(User *u) {
_cleanup_free_ char *display = NULL, *realtime = NULL, *monotonic = NULL;
Session *s = NULL;
int r;
assert(u);
r = parse_env_file(u->state_file, NEWLINE,
"RUNTIME", &u->runtime_path,
"SERVICE", &u->service,
"SERVICE_JOB", &u->service_job,
"SLICE", &u->slice,
"SLICE_JOB", &u->slice_job,
"DISPLAY", &display,
"REALTIME", &realtime,
"MONOTONIC", &monotonic,
NULL);
if (r < 0) {
if (r == -ENOENT)
return 0;
log_error_errno(r, "Failed to read %s: %m", u->state_file);
return r;
}
if (display)
s = hashmap_get(u->manager->sessions, display);
if (s && s->display && display_is_local(s->display))
u->display = s;
if (realtime) {
unsigned long long l;
if (sscanf(realtime, "%llu", &l) > 0)
u->timestamp.realtime = l;
}
if (monotonic) {
unsigned long long l;
if (sscanf(monotonic, "%llu", &l) > 0)
u->timestamp.monotonic = l;
}
return r;
}
static int user_mkdir_runtime_path(User *u) {
char *p;
int r;
assert(u);
r = mkdir_safe_label("/run/user", 0755, 0, 0);
if (r < 0)
return log_error_errno(r, "Failed to create /run/user: %m");
if (!u->runtime_path) {
if (asprintf(&p, "/run/user/" UID_FMT, u->uid) < 0)
return log_oom();
} else
p = u->runtime_path;
if (path_is_mount_point(p, 0) <= 0) {
_cleanup_free_ char *t = NULL;
(void) mkdir_label(p, 0700);
if (mac_smack_use())
r = asprintf(&t, "mode=0700,smackfsroot=*,uid=" UID_FMT ",gid=" GID_FMT ",size=%zu", u->uid, u->gid, u->manager->runtime_dir_size);
else
r = asprintf(&t, "mode=0700,uid=" UID_FMT ",gid=" GID_FMT ",size=%zu", u->uid, u->gid, u->manager->runtime_dir_size);
if (r < 0) {
r = log_oom();
goto fail;
}
r = mount("tmpfs", p, "tmpfs", MS_NODEV|MS_NOSUID, t);
if (r < 0) {
if (errno != EPERM) {
r = log_error_errno(errno, "Failed to mount per-user tmpfs directory %s: %m", p);
goto fail;
}
/* Lacking permissions, maybe
* CAP_SYS_ADMIN-less container? In this case,
* just use a normal directory. */
r = chmod_and_chown(p, 0700, u->uid, u->gid);
if (r < 0) {
log_error_errno(r, "Failed to change runtime directory ownership and mode: %m");
goto fail;
}
}
r = label_fix(p, false, false);
if (r < 0)
log_warning_errno(r, "Failed to fix label of '%s', ignoring: %m", p);
}
u->runtime_path = p;
return 0;
fail:
if (p) {
/* Try to clean up, but ignore errors */
(void) rmdir(p);
free(p);
}
u->runtime_path = NULL;
return r;
}
static int user_start_slice(User *u) {
char *job;
int r;
assert(u);
if (!u->slice) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
char lu[DECIMAL_STR_MAX(uid_t) + 1], *slice;
sprintf(lu, UID_FMT, u->uid);
r = slice_build_subslice(SPECIAL_USER_SLICE, lu, &slice);
if (r < 0)
return r;
r = manager_start_unit(u->manager, slice, &error, &job);
if (r < 0) {
log_error("Failed to start user slice: %s", bus_error_message(&error, r));
free(slice);
} else {
u->slice = slice;
free(u->slice_job);
u->slice_job = job;
}
}
if (u->slice)
hashmap_put(u->manager->user_units, u->slice, u);
return 0;
}
static int user_start_service(User *u) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
char *job;
int r;
assert(u);
if (!u->service) {
char lu[DECIMAL_STR_MAX(uid_t) + 1], *service;
sprintf(lu, UID_FMT, u->uid);
r = unit_name_build("user", lu, ".service", &service);
if (r < 0)
return log_error_errno(r, "Failed to build service name: %m");
r = manager_start_unit(u->manager, service, &error, &job);
if (r < 0) {
log_error("Failed to start user service: %s", bus_error_message(&error, r));
free(service);
} else {
u->service = service;
free(u->service_job);
u->service_job = job;
}
}
if (u->service)
hashmap_put(u->manager->user_units, u->service, u);
return 0;
}
int user_start(User *u) {
int r;
assert(u);
if (u->started)
return 0;
log_debug("New user %s logged in.", u->name);
/* Make XDG_RUNTIME_DIR */
r = user_mkdir_runtime_path(u);
if (r < 0)
return r;
/* Create cgroup */
r = user_start_slice(u);
if (r < 0)
return r;
/* Save the user data so far, because pam_systemd will read the
* XDG_RUNTIME_DIR out of it while starting up systemd --user.
* We need to do user_save_internal() because we have not
* "officially" started yet. */
user_save_internal(u);
/* Spawn user systemd */
r = user_start_service(u);
if (r < 0)
return r;
if (!dual_timestamp_is_set(&u->timestamp))
dual_timestamp_get(&u->timestamp);
u->started = true;
/* Save new user data */
user_save(u);
user_send_signal(u, true);
return 0;
}
static int user_stop_slice(User *u) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
char *job;
int r;
assert(u);
if (!u->slice)
return 0;
r = manager_stop_unit(u->manager, u->slice, &error, &job);
if (r < 0) {
log_error("Failed to stop user slice: %s", bus_error_message(&error, r));
return r;
}
free(u->slice_job);
u->slice_job = job;
return r;
}
static int user_stop_service(User *u) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
char *job;
int r;
assert(u);
if (!u->service)
return 0;
r = manager_stop_unit(u->manager, u->service, &error, &job);
if (r < 0) {
log_error("Failed to stop user service: %s", bus_error_message(&error, r));
return r;
}
free(u->service_job);
u->service_job = job;
return r;
}
static int user_remove_runtime_path(User *u) {
int r;
assert(u);
if (!u->runtime_path)
return 0;
r = rm_rf(u->runtime_path, 0);
if (r < 0)
log_error_errno(r, "Failed to remove runtime directory %s: %m", u->runtime_path);
/* Ignore cases where the directory isn't mounted, as that's
* quite possible, if we lacked the permissions to mount
* something */
r = umount2(u->runtime_path, MNT_DETACH);
if (r < 0 && errno != EINVAL && errno != ENOENT)
log_error_errno(errno, "Failed to unmount user runtime directory %s: %m", u->runtime_path);
r = rm_rf(u->runtime_path, REMOVE_ROOT);
if (r < 0)
log_error_errno(r, "Failed to remove runtime directory %s: %m", u->runtime_path);
u->runtime_path = mfree(u->runtime_path);
return r;
}
int user_stop(User *u, bool force) {
Session *s;
int r = 0, k;
assert(u);
/* Stop jobs have already been queued */
if (u->stopping) {
user_save(u);
return r;
}
LIST_FOREACH(sessions_by_user, s, u->sessions) {
k = session_stop(s, force);
if (k < 0)
r = k;
}
/* Kill systemd */
k = user_stop_service(u);
if (k < 0)
r = k;
/* Kill cgroup */
k = user_stop_slice(u);
if (k < 0)
r = k;
u->stopping = true;
user_save(u);
return r;
}
int user_finalize(User *u) {
Session *s;
int r = 0, k;
assert(u);
if (u->started)
log_debug("User %s logged out.", u->name);
LIST_FOREACH(sessions_by_user, s, u->sessions) {
k = session_finalize(s);
if (k < 0)
r = k;
}
/* Kill XDG_RUNTIME_DIR */
k = user_remove_runtime_path(u);
if (k < 0)
r = k;
/* Clean SysV + POSIX IPC objects */
if (u->manager->remove_ipc) {
k = clean_ipc(u->uid);
if (k < 0)
r = k;
}
unlink(u->state_file);
user_add_to_gc_queue(u);
if (u->started) {
user_send_signal(u, false);
u->started = false;
}
return r;
}
int user_get_idle_hint(User *u, dual_timestamp *t) {
Session *s;
bool idle_hint = true;
dual_timestamp ts = DUAL_TIMESTAMP_NULL;
assert(u);
LIST_FOREACH(sessions_by_user, s, u->sessions) {
dual_timestamp k;
int ih;
ih = session_get_idle_hint(s, &k);
if (ih < 0)
return ih;
if (!ih) {
if (!idle_hint) {
if (k.monotonic < ts.monotonic)
ts = k;
} else {
idle_hint = false;
ts = k;
}
} else if (idle_hint) {
if (k.monotonic > ts.monotonic)
ts = k;
}
}
if (t)
*t = ts;
return idle_hint;
}
int user_check_linger_file(User *u) {
_cleanup_free_ char *cc = NULL;
char *p = NULL;
cc = cescape(u->name);
if (!cc)
return -ENOMEM;
p = strjoina("/var/lib/systemd/linger/", cc);
return access(p, F_OK) >= 0;
}
bool user_check_gc(User *u, bool drop_not_started) {
assert(u);
if (drop_not_started && !u->started)
return false;
if (u->sessions)
return true;
if (user_check_linger_file(u) > 0)
return true;
if (u->slice_job && manager_job_is_active(u->manager, u->slice_job))
return true;
if (u->service_job && manager_job_is_active(u->manager, u->service_job))
return true;
return false;
}
void user_add_to_gc_queue(User *u) {
assert(u);
if (u->in_gc_queue)
return;
LIST_PREPEND(gc_queue, u->manager->user_gc_queue, u);
u->in_gc_queue = true;
}
UserState user_get_state(User *u) {
Session *i;
assert(u);
if (u->stopping)
return USER_CLOSING;
if (!u->started || u->slice_job || u->service_job)
return USER_OPENING;
if (u->sessions) {
bool all_closing = true;
LIST_FOREACH(sessions_by_user, i, u->sessions) {
SessionState state;
state = session_get_state(i);
if (state == SESSION_ACTIVE)
return USER_ACTIVE;
if (state != SESSION_CLOSING)
all_closing = false;
}
return all_closing ? USER_CLOSING : USER_ONLINE;
}
if (user_check_linger_file(u) > 0)
return USER_LINGERING;
return USER_CLOSING;
}
int user_kill(User *u, int signo) {
assert(u);
if (!u->slice)
return -ESRCH;
return manager_kill_unit(u->manager, u->slice, KILL_ALL, signo, NULL);
}
static bool elect_display_filter(Session *s) {
/* Return true if the session is a candidate for the users primary
* session or display. */
assert(s);
return (s->class == SESSION_USER && !s->stopping);
}
static int elect_display_compare(Session *s1, Session *s2) {
/* Indexed by SessionType. Lower numbers mean more preferred. */
const int type_ranks[_SESSION_TYPE_MAX] = {
[SESSION_UNSPECIFIED] = 0,
[SESSION_TTY] = -2,
[SESSION_X11] = -3,
[SESSION_WAYLAND] = -3,
[SESSION_MIR] = -3,
[SESSION_WEB] = -1,
};
/* Calculate the partial order relationship between s1 and s2,
* returning < 0 if s1 is preferred as the users primary session,
* 0 if s1 and s2 are equally preferred or incomparable, or > 0 if s2
* is preferred.
*
* s1 or s2 may be NULL. */
if (!s1 && !s2)
return 0;
if ((s1 == NULL) != (s2 == NULL))
return (s1 == NULL) - (s2 == NULL);
if (s1->stopping != s2->stopping)
return s1->stopping - s2->stopping;
if ((s1->class != SESSION_USER) != (s2->class != SESSION_USER))
return (s1->class != SESSION_USER) - (s2->class != SESSION_USER);
if ((s1->type == _SESSION_TYPE_INVALID) != (s2->type == _SESSION_TYPE_INVALID))
return (s1->type == _SESSION_TYPE_INVALID) - (s2->type == _SESSION_TYPE_INVALID);
if (s1->type != s2->type)
return type_ranks[s1->type] - type_ranks[s2->type];
return 0;
}
void user_elect_display(User *u) {
Session *s;
assert(u);
/* This elects a primary session for each user, which we call
* the "display". We try to keep the assignment stable, but we
* "upgrade" to better choices. */
log_debug("Electing new display for user %s", u->name);
LIST_FOREACH(sessions_by_user, s, u->sessions) {
if (!elect_display_filter(s)) {
log_debug("Ignoring session %s", s->id);
continue;
}
if (elect_display_compare(s, u->display) < 0) {
log_debug("Choosing session %s in preference to %s", s->id, u->display ? u->display->id : "-");
u->display = s;
}
}
}
static const char* const user_state_table[_USER_STATE_MAX] = {
[USER_OFFLINE] = "offline",
[USER_OPENING] = "opening",
[USER_LINGERING] = "lingering",
[USER_ONLINE] = "online",
[USER_ACTIVE] = "active",
[USER_CLOSING] = "closing"
};
DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);
int config_parse_tmpfs_size(
const char* unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
size_t *sz = data;
const char *e;
int r;
assert(filename);
assert(lvalue);
assert(rvalue);
assert(data);
e = endswith(rvalue, "%");
if (e) {
unsigned long ul;
char *f;
errno = 0;
ul = strtoul(rvalue, &f, 10);
if (errno != 0 || f != e) {
log_syntax(unit, LOG_ERR, filename, line, errno ? errno : EINVAL, "Failed to parse percentage value, ignoring: %s", rvalue);
return 0;
}
if (ul <= 0 || ul >= 100) {
log_syntax(unit, LOG_ERR, filename, line, errno ? errno : EINVAL, "Percentage value out of range, ignoring: %s", rvalue);
return 0;
}
*sz = PAGE_ALIGN((size_t) ((physical_memory() * (uint64_t) ul) / (uint64_t) 100));
} else {
off_t o;
r = parse_size(rvalue, 1024, &o);
if (r < 0 || (off_t) (size_t) o != o) {
log_syntax(unit, LOG_ERR, filename, line, r < 0 ? -r : ERANGE, "Failed to parse size value, ignoring: %s", rvalue);
return 0;
}
*sz = PAGE_ALIGN((size_t) o);
}
return 0;
}