util.c revision 4e731273edfe852a3eee2949cd20f49fd5b4f6d7
/*-*- 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 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 <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <glob.h>
#include <grp.h>
#include <langinfo.h>
#include <libintl.h>
#include <limits.h>
#include <linux/magic.h>
#include <linux/oom.h>
#include <linux/sched.h>
#include <locale.h>
#include <poll.h>
#include <pwd.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/personality.h>
#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <sys/vfs.h>
#include <sys/wait.h>
#include <syslog.h>
#include <unistd.h>
/* When we include libgen.h because we need dirname() we immediately
* undefine basename() since libgen.h defines it as a macro to the
* POSIX version which is really broken. We prefer GNU basename(). */
#include <libgen.h>
#undef basename
#ifdef HAVE_SYS_AUXV_H
#include <sys/auxv.h>
#endif
/* We include linux/fs.h as last of the system headers, as it
* otherwise conflicts with sys/mount.h. Yay, Linux is great! */
#include <linux/fs.h>
#include "build.h"
#include "def.h"
#include "device-nodes.h"
#include "env-util.h"
#include "escape.h"
#include "exit-status.h"
#include "fd-util.h"
#include "fileio.h"
#include "formats-util.h"
#include "gunicode.h"
#include "hashmap.h"
#include "hostname-util.h"
#include "ioprio.h"
#include "log.h"
#include "macro.h"
#include "missing.h"
#include "mkdir.h"
#include "hexdecoct.h"
#include "parse-util.h"
#include "path-util.h"
#include "process-util.h"
#include "random-util.h"
#include "signal-util.h"
#include "sparse-endian.h"
#include "string-table.h"
#include "string-util.h"
#include "strv.h"
#include "terminal-util.h"
#include "user-util.h"
#include "utf8.h"
#include "util.h"
#include "virt.h"
#include "dirent-util.h"
#include "stat-util.h"
/* Put this test here for a lack of better place */
assert_cc(EAGAIN == EWOULDBLOCK);
int saved_argc = 0;
char **saved_argv = NULL;
size_t page_size(void) {
static thread_local size_t pgsz = 0;
long r;
if (_likely_(pgsz > 0))
return pgsz;
r = sysconf(_SC_PAGESIZE);
assert(r > 0);
pgsz = (size_t) r;
return pgsz;
}
bool fstype_is_network(const char *fstype) {
static const char table[] =
"afs\0"
"cifs\0"
"smbfs\0"
"sshfs\0"
"ncpfs\0"
"ncp\0"
"nfs\0"
"nfs4\0"
"gfs\0"
"gfs2\0"
"glusterfs\0";
const char *x;
x = startswith(fstype, "fuse.");
if (x)
fstype = x;
return nulstr_contains(table, fstype);
}
void rename_process(const char name[8]) {
assert(name);
/* This is a like a poor man's setproctitle(). It changes the
* comm field, argv[0], and also the glibc's internally used
* name of the process. For the first one a limit of 16 chars
* applies, to the second one usually one of 10 (i.e. length
* of "/sbin/init"), to the third one one of 7 (i.e. length of
* "systemd"). If you pass a longer string it will be
* truncated */
prctl(PR_SET_NAME, name);
if (program_invocation_name)
strncpy(program_invocation_name, name, strlen(program_invocation_name));
if (saved_argc > 0) {
int i;
if (saved_argv[0])
strncpy(saved_argv[0], name, strlen(saved_argv[0]));
for (i = 1; i < saved_argc; i++) {
if (!saved_argv[i])
break;
memzero(saved_argv[i], strlen(saved_argv[i]));
}
}
}
int running_in_chroot(void) {
int ret;
ret = files_same("/proc/1/root", "/");
if (ret < 0)
return ret;
return ret == 0;
}
noreturn void freeze(void) {
/* Make sure nobody waits for us on a socket anymore */
close_all_fds(NULL, 0);
sync();
for (;;)
pause();
}
static int do_execute(char **directories, usec_t timeout, char *argv[]) {
_cleanup_hashmap_free_free_ Hashmap *pids = NULL;
_cleanup_set_free_free_ Set *seen = NULL;
char **directory;
/* We fork this all off from a child process so that we can
* somewhat cleanly make use of SIGALRM to set a time limit */
(void) reset_all_signal_handlers();
(void) reset_signal_mask();
assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
pids = hashmap_new(NULL);
if (!pids)
return log_oom();
seen = set_new(&string_hash_ops);
if (!seen)
return log_oom();
STRV_FOREACH(directory, directories) {
_cleanup_closedir_ DIR *d;
struct dirent *de;
d = opendir(*directory);
if (!d) {
if (errno == ENOENT)
continue;
return log_error_errno(errno, "Failed to open directory %s: %m", *directory);
}
FOREACH_DIRENT(de, d, break) {
_cleanup_free_ char *path = NULL;
pid_t pid;
int r;
if (!dirent_is_file(de))
continue;
if (set_contains(seen, de->d_name)) {
log_debug("%1$s/%2$s skipped (%2$s was already seen).", *directory, de->d_name);
continue;
}
r = set_put_strdup(seen, de->d_name);
if (r < 0)
return log_oom();
path = strjoin(*directory, "/", de->d_name, NULL);
if (!path)
return log_oom();
if (null_or_empty_path(path)) {
log_debug("%s is empty (a mask).", path);
continue;
}
pid = fork();
if (pid < 0) {
log_error_errno(errno, "Failed to fork: %m");
continue;
} else if (pid == 0) {
char *_argv[2];
assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0);
if (!argv) {
_argv[0] = path;
_argv[1] = NULL;
argv = _argv;
} else
argv[0] = path;
execv(path, argv);
return log_error_errno(errno, "Failed to execute %s: %m", path);
}
log_debug("Spawned %s as " PID_FMT ".", path, pid);
r = hashmap_put(pids, UINT_TO_PTR(pid), path);
if (r < 0)
return log_oom();
path = NULL;
}
}
/* Abort execution of this process after the timout. We simply
* rely on SIGALRM as default action terminating the process,
* and turn on alarm(). */
if (timeout != USEC_INFINITY)
alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC);
while (!hashmap_isempty(pids)) {
_cleanup_free_ char *path = NULL;
pid_t pid;
pid = PTR_TO_UINT(hashmap_first_key(pids));
assert(pid > 0);
path = hashmap_remove(pids, UINT_TO_PTR(pid));
assert(path);
wait_for_terminate_and_warn(path, pid, true);
}
return 0;
}
void execute_directories(const char* const* directories, usec_t timeout, char *argv[]) {
pid_t executor_pid;
int r;
char *name;
char **dirs = (char**) directories;
assert(!strv_isempty(dirs));
name = basename(dirs[0]);
assert(!isempty(name));
/* Executes all binaries in the directories in parallel and waits
* for them to finish. Optionally a timeout is applied. If a file
* with the same name exists in more than one directory, the
* earliest one wins. */
executor_pid = fork();
if (executor_pid < 0) {
log_error_errno(errno, "Failed to fork: %m");
return;
} else if (executor_pid == 0) {
r = do_execute(dirs, timeout, argv);
_exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
}
wait_for_terminate_and_warn(name, executor_pid, true);
}
bool plymouth_running(void) {
return access("/run/plymouth/pid", F_OK) >= 0;
}
bool display_is_local(const char *display) {
assert(display);
return
display[0] == ':' &&
display[1] >= '0' &&
display[1] <= '9';
}
int socket_from_display(const char *display, char **path) {
size_t k;
char *f, *c;
assert(display);
assert(path);
if (!display_is_local(display))
return -EINVAL;
k = strspn(display+1, "0123456789");
f = new(char, strlen("/tmp/.X11-unix/X") + k + 1);
if (!f)
return -ENOMEM;
c = stpcpy(f, "/tmp/.X11-unix/X");
memcpy(c, display+1, k);
c[k] = 0;
*path = f;
return 0;
}
int glob_exists(const char *path) {
_cleanup_globfree_ glob_t g = {};
int k;
assert(path);
errno = 0;
k = glob(path, GLOB_NOSORT|GLOB_BRACE, NULL, &g);
if (k == GLOB_NOMATCH)
return 0;
else if (k == GLOB_NOSPACE)
return -ENOMEM;
else if (k == 0)
return !strv_isempty(g.gl_pathv);
else
return errno ? -errno : -EIO;
}
int glob_extend(char ***strv, const char *path) {
_cleanup_globfree_ glob_t g = {};
int k;
char **p;
errno = 0;
k = glob(path, GLOB_NOSORT|GLOB_BRACE, NULL, &g);
if (k == GLOB_NOMATCH)
return -ENOENT;
else if (k == GLOB_NOSPACE)
return -ENOMEM;
else if (k != 0 || strv_isempty(g.gl_pathv))
return errno ? -errno : -EIO;
STRV_FOREACH(p, g.gl_pathv) {
k = strv_extend(strv, *p);
if (k < 0)
break;
}
return k;
}
int block_get_whole_disk(dev_t d, dev_t *ret) {
char *p, *s;
int r;
unsigned n, m;
assert(ret);
/* If it has a queue this is good enough for us */
if (asprintf(&p, "/sys/dev/block/%u:%u/queue", major(d), minor(d)) < 0)
return -ENOMEM;
r = access(p, F_OK);
free(p);
if (r >= 0) {
*ret = d;
return 0;
}
/* If it is a partition find the originating device */
if (asprintf(&p, "/sys/dev/block/%u:%u/partition", major(d), minor(d)) < 0)
return -ENOMEM;
r = access(p, F_OK);
free(p);
if (r < 0)
return -ENOENT;
/* Get parent dev_t */
if (asprintf(&p, "/sys/dev/block/%u:%u/../dev", major(d), minor(d)) < 0)
return -ENOMEM;
r = read_one_line_file(p, &s);
free(p);
if (r < 0)
return r;
r = sscanf(s, "%u:%u", &m, &n);
free(s);
if (r != 2)
return -EINVAL;
/* Only return this if it is really good enough for us. */
if (asprintf(&p, "/sys/dev/block/%u:%u/queue", m, n) < 0)
return -ENOMEM;
r = access(p, F_OK);
free(p);
if (r >= 0) {
*ret = makedev(m, n);
return 0;
}
return -ENOENT;
}
static const char *const ioprio_class_table[] = {
[IOPRIO_CLASS_NONE] = "none",
[IOPRIO_CLASS_RT] = "realtime",
[IOPRIO_CLASS_BE] = "best-effort",
[IOPRIO_CLASS_IDLE] = "idle"
};
DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(ioprio_class, int, INT_MAX);
static const char *const sigchld_code_table[] = {
[CLD_EXITED] = "exited",
[CLD_KILLED] = "killed",
[CLD_DUMPED] = "dumped",
[CLD_TRAPPED] = "trapped",
[CLD_STOPPED] = "stopped",
[CLD_CONTINUED] = "continued",
};
DEFINE_STRING_TABLE_LOOKUP(sigchld_code, int);
static const char *const log_facility_unshifted_table[LOG_NFACILITIES] = {
[LOG_FAC(LOG_KERN)] = "kern",
[LOG_FAC(LOG_USER)] = "user",
[LOG_FAC(LOG_MAIL)] = "mail",
[LOG_FAC(LOG_DAEMON)] = "daemon",
[LOG_FAC(LOG_AUTH)] = "auth",
[LOG_FAC(LOG_SYSLOG)] = "syslog",
[LOG_FAC(LOG_LPR)] = "lpr",
[LOG_FAC(LOG_NEWS)] = "news",
[LOG_FAC(LOG_UUCP)] = "uucp",
[LOG_FAC(LOG_CRON)] = "cron",
[LOG_FAC(LOG_AUTHPRIV)] = "authpriv",
[LOG_FAC(LOG_FTP)] = "ftp",
[LOG_FAC(LOG_LOCAL0)] = "local0",
[LOG_FAC(LOG_LOCAL1)] = "local1",
[LOG_FAC(LOG_LOCAL2)] = "local2",
[LOG_FAC(LOG_LOCAL3)] = "local3",
[LOG_FAC(LOG_LOCAL4)] = "local4",
[LOG_FAC(LOG_LOCAL5)] = "local5",
[LOG_FAC(LOG_LOCAL6)] = "local6",
[LOG_FAC(LOG_LOCAL7)] = "local7"
};
DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(log_facility_unshifted, int, LOG_FAC(~0));
bool log_facility_unshifted_is_valid(int facility) {
return facility >= 0 && facility <= LOG_FAC(~0);
}
static const char *const log_level_table[] = {
[LOG_EMERG] = "emerg",
[LOG_ALERT] = "alert",
[LOG_CRIT] = "crit",
[LOG_ERR] = "err",
[LOG_WARNING] = "warning",
[LOG_NOTICE] = "notice",
[LOG_INFO] = "info",
[LOG_DEBUG] = "debug"
};
DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(log_level, int, LOG_DEBUG);
bool log_level_is_valid(int level) {
return level >= 0 && level <= LOG_DEBUG;
}
static const char* const sched_policy_table[] = {
[SCHED_OTHER] = "other",
[SCHED_BATCH] = "batch",
[SCHED_IDLE] = "idle",
[SCHED_FIFO] = "fifo",
[SCHED_RR] = "rr"
};
DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(sched_policy, int, INT_MAX);
bool kexec_loaded(void) {
bool loaded = false;
char *s;
if (read_one_line_file("/sys/kernel/kexec_loaded", &s) >= 0) {
if (s[0] == '1')
loaded = true;
free(s);
}
return loaded;
}
int prot_from_flags(int flags) {
switch (flags & O_ACCMODE) {
case O_RDONLY:
return PROT_READ;
case O_WRONLY:
return PROT_WRITE;
case O_RDWR:
return PROT_READ|PROT_WRITE;
default:
return -EINVAL;
}
}
void* memdup(const void *p, size_t l) {
void *r;
assert(p);
r = malloc(l);
if (!r)
return NULL;
memcpy(r, p, l);
return r;
}
int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *path, ...) {
bool stdout_is_tty, stderr_is_tty;
pid_t parent_pid, agent_pid;
sigset_t ss, saved_ss;
unsigned n, i;
va_list ap;
char **l;
assert(pid);
assert(path);
/* Spawns a temporary TTY agent, making sure it goes away when
* we go away */
parent_pid = getpid();
/* First we temporarily block all signals, so that the new
* child has them blocked initially. This way, we can be sure
* that SIGTERMs are not lost we might send to the agent. */
assert_se(sigfillset(&ss) >= 0);
assert_se(sigprocmask(SIG_SETMASK, &ss, &saved_ss) >= 0);
agent_pid = fork();
if (agent_pid < 0) {
assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0);
return -errno;
}
if (agent_pid != 0) {
assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0);
*pid = agent_pid;
return 0;
}
/* In the child:
*
* Make sure the agent goes away when the parent dies */
if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)
_exit(EXIT_FAILURE);
/* Make sure we actually can kill the agent, if we need to, in
* case somebody invoked us from a shell script that trapped
* SIGTERM or so... */
(void) reset_all_signal_handlers();
(void) reset_signal_mask();
/* Check whether our parent died before we were able
* to set the death signal and unblock the signals */
if (getppid() != parent_pid)
_exit(EXIT_SUCCESS);
/* Don't leak fds to the agent */
close_all_fds(except, n_except);
stdout_is_tty = isatty(STDOUT_FILENO);
stderr_is_tty = isatty(STDERR_FILENO);
if (!stdout_is_tty || !stderr_is_tty) {
int fd;
/* Detach from stdout/stderr. and reopen
* /dev/tty for them. This is important to
* ensure that when systemctl is started via
* popen() or a similar call that expects to
* read EOF we actually do generate EOF and
* not delay this indefinitely by because we
* keep an unused copy of stdin around. */
fd = open("/dev/tty", O_WRONLY);
if (fd < 0) {
log_error_errno(errno, "Failed to open /dev/tty: %m");
_exit(EXIT_FAILURE);
}
if (!stdout_is_tty)
dup2(fd, STDOUT_FILENO);
if (!stderr_is_tty)
dup2(fd, STDERR_FILENO);
if (fd > 2)
close(fd);
}
/* Count arguments */
va_start(ap, path);
for (n = 0; va_arg(ap, char*); n++)
;
va_end(ap);
/* Allocate strv */
l = alloca(sizeof(char *) * (n + 1));
/* Fill in arguments */
va_start(ap, path);
for (i = 0; i <= n; i++)
l[i] = va_arg(ap, char*);
va_end(ap);
execv(path, l);
_exit(EXIT_FAILURE);
}
bool http_etag_is_valid(const char *etag) {
if (isempty(etag))
return false;
if (!endswith(etag, "\""))
return false;
if (!startswith(etag, "\"") && !startswith(etag, "W/\""))
return false;
return true;
}
bool http_url_is_valid(const char *url) {
const char *p;
if (isempty(url))
return false;
p = startswith(url, "http://");
if (!p)
p = startswith(url, "https://");
if (!p)
return false;
if (isempty(p))
return false;
return ascii_is_valid(p);
}
bool documentation_url_is_valid(const char *url) {
const char *p;
if (isempty(url))
return false;
if (http_url_is_valid(url))
return true;
p = startswith(url, "file:/");
if (!p)
p = startswith(url, "info:");
if (!p)
p = startswith(url, "man:");
if (isempty(p))
return false;
return ascii_is_valid(p);
}
bool in_initrd(void) {
static int saved = -1;
struct statfs s;
if (saved >= 0)
return saved;
/* We make two checks here:
*
* 1. the flag file /etc/initrd-release must exist
* 2. the root file system must be a memory file system
*
* The second check is extra paranoia, since misdetecting an
* initrd can have bad bad consequences due the initrd
* emptying when transititioning to the main systemd.
*/
saved = access("/etc/initrd-release", F_OK) >= 0 &&
statfs("/", &s) >= 0 &&
is_temporary_fs(&s);
return saved;
}
/* hey glibc, APIs with callbacks without a user pointer are so useless */
void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
int (*compar) (const void *, const void *, void *), void *arg) {
size_t l, u, idx;
const void *p;
int comparison;
l = 0;
u = nmemb;
while (l < u) {
idx = (l + u) / 2;
p = (void *)(((const char *) base) + (idx * size));
comparison = compar(key, p, arg);
if (comparison < 0)
u = idx;
else if (comparison > 0)
l = idx + 1;
else
return (void *)p;
}
return NULL;
}
int on_ac_power(void) {
bool found_offline = false, found_online = false;
_cleanup_closedir_ DIR *d = NULL;
d = opendir("/sys/class/power_supply");
if (!d)
return errno == ENOENT ? true : -errno;
for (;;) {
struct dirent *de;
_cleanup_close_ int fd = -1, device = -1;
char contents[6];
ssize_t n;
errno = 0;
de = readdir(d);
if (!de && errno != 0)
return -errno;
if (!de)
break;
if (hidden_file(de->d_name))
continue;
device = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (device < 0) {
if (errno == ENOENT || errno == ENOTDIR)
continue;
return -errno;
}
fd = openat(device, "type", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0) {
if (errno == ENOENT)
continue;
return -errno;
}
n = read(fd, contents, sizeof(contents));
if (n < 0)
return -errno;
if (n != 6 || memcmp(contents, "Mains\n", 6))
continue;
safe_close(fd);
fd = openat(device, "online", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0) {
if (errno == ENOENT)
continue;
return -errno;
}
n = read(fd, contents, sizeof(contents));
if (n < 0)
return -errno;
if (n != 2 || contents[1] != '\n')
return -EIO;
if (contents[0] == '1') {
found_online = true;
break;
} else if (contents[0] == '0')
found_offline = true;
else
return -EIO;
}
return found_online || !found_offline;
}
void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size) {
size_t a, newalloc;
void *q;
assert(p);
assert(allocated);
if (*allocated >= need)
return *p;
newalloc = MAX(need * 2, 64u / size);
a = newalloc * size;
/* check for overflows */
if (a < size * need)
return NULL;
q = realloc(*p, a);
if (!q)
return NULL;
*p = q;
*allocated = newalloc;
return q;
}
void* greedy_realloc0(void **p, size_t *allocated, size_t need, size_t size) {
size_t prev;
uint8_t *q;
assert(p);
assert(allocated);
prev = *allocated;
q = greedy_realloc(p, allocated, need, size);
if (!q)
return NULL;
if (*allocated > prev)
memzero(q + prev * size, (*allocated - prev) * size);
return q;
}
bool id128_is_valid(const char *s) {
size_t i, l;
l = strlen(s);
if (l == 32) {
/* Simple formatted 128bit hex string */
for (i = 0; i < l; i++) {
char c = s[i];
if (!(c >= '0' && c <= '9') &&
!(c >= 'a' && c <= 'z') &&
!(c >= 'A' && c <= 'Z'))
return false;
}
} else if (l == 36) {
/* Formatted UUID */
for (i = 0; i < l; i++) {
char c = s[i];
if ((i == 8 || i == 13 || i == 18 || i == 23)) {
if (c != '-')
return false;
} else {
if (!(c >= '0' && c <= '9') &&
!(c >= 'a' && c <= 'z') &&
!(c >= 'A' && c <= 'Z'))
return false;
}
}
} else
return false;
return true;
}
int container_get_leader(const char *machine, pid_t *pid) {
_cleanup_free_ char *s = NULL, *class = NULL;
const char *p;
pid_t leader;
int r;
assert(machine);
assert(pid);
if (!machine_name_is_valid(machine))
return -EINVAL;
p = strjoina("/run/systemd/machines/", machine);
r = parse_env_file(p, NEWLINE, "LEADER", &s, "CLASS", &class, NULL);
if (r == -ENOENT)
return -EHOSTDOWN;
if (r < 0)
return r;
if (!s)
return -EIO;
if (!streq_ptr(class, "container"))
return -EIO;
r = parse_pid(s, &leader);
if (r < 0)
return r;
if (leader <= 1)
return -EIO;
*pid = leader;
return 0;
}
int namespace_open(pid_t pid, int *pidns_fd, int *mntns_fd, int *netns_fd, int *userns_fd, int *root_fd) {
_cleanup_close_ int pidnsfd = -1, mntnsfd = -1, netnsfd = -1, usernsfd = -1;
int rfd = -1;
assert(pid >= 0);
if (mntns_fd) {
const char *mntns;
mntns = procfs_file_alloca(pid, "ns/mnt");
mntnsfd = open(mntns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (mntnsfd < 0)
return -errno;
}
if (pidns_fd) {
const char *pidns;
pidns = procfs_file_alloca(pid, "ns/pid");
pidnsfd = open(pidns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (pidnsfd < 0)
return -errno;
}
if (netns_fd) {
const char *netns;
netns = procfs_file_alloca(pid, "ns/net");
netnsfd = open(netns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (netnsfd < 0)
return -errno;
}
if (userns_fd) {
const char *userns;
userns = procfs_file_alloca(pid, "ns/user");
usernsfd = open(userns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (usernsfd < 0 && errno != ENOENT)
return -errno;
}
if (root_fd) {
const char *root;
root = procfs_file_alloca(pid, "root");
rfd = open(root, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
if (rfd < 0)
return -errno;
}
if (pidns_fd)
*pidns_fd = pidnsfd;
if (mntns_fd)
*mntns_fd = mntnsfd;
if (netns_fd)
*netns_fd = netnsfd;
if (userns_fd)
*userns_fd = usernsfd;
if (root_fd)
*root_fd = rfd;
pidnsfd = mntnsfd = netnsfd = usernsfd = -1;
return 0;
}
int namespace_enter(int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int root_fd) {
if (userns_fd >= 0) {
/* Can't setns to your own userns, since then you could
* escalate from non-root to root in your own namespace, so
* check if namespaces equal before attempting to enter. */
_cleanup_free_ char *userns_fd_path = NULL;
int r;
if (asprintf(&userns_fd_path, "/proc/self/fd/%d", userns_fd) < 0)
return -ENOMEM;
r = files_same(userns_fd_path, "/proc/self/ns/user");
if (r < 0)
return r;
if (r)
userns_fd = -1;
}
if (pidns_fd >= 0)
if (setns(pidns_fd, CLONE_NEWPID) < 0)
return -errno;
if (mntns_fd >= 0)
if (setns(mntns_fd, CLONE_NEWNS) < 0)
return -errno;
if (netns_fd >= 0)
if (setns(netns_fd, CLONE_NEWNET) < 0)
return -errno;
if (userns_fd >= 0)
if (setns(userns_fd, CLONE_NEWUSER) < 0)
return -errno;
if (root_fd >= 0) {
if (fchdir(root_fd) < 0)
return -errno;
if (chroot(".") < 0)
return -errno;
}
return reset_uid_gid();
}
unsigned long personality_from_string(const char *p) {
/* Parse a personality specifier. We introduce our own
* identifiers that indicate specific ABIs, rather than just
* hints regarding the register size, since we want to keep
* things open for multiple locally supported ABIs for the
* same register size. We try to reuse the ABI identifiers
* used by libseccomp. */
#if defined(__x86_64__)
if (streq(p, "x86"))
return PER_LINUX32;
if (streq(p, "x86-64"))
return PER_LINUX;
#elif defined(__i386__)
if (streq(p, "x86"))
return PER_LINUX;
#elif defined(__s390x__)
if (streq(p, "s390"))
return PER_LINUX32;
if (streq(p, "s390x"))
return PER_LINUX;
#elif defined(__s390__)
if (streq(p, "s390"))
return PER_LINUX;
#endif
return PERSONALITY_INVALID;
}
const char* personality_to_string(unsigned long p) {
#if defined(__x86_64__)
if (p == PER_LINUX32)
return "x86";
if (p == PER_LINUX)
return "x86-64";
#elif defined(__i386__)
if (p == PER_LINUX)
return "x86";
#elif defined(__s390x__)
if (p == PER_LINUX)
return "s390x";
if (p == PER_LINUX32)
return "s390";
#elif defined(__s390__)
if (p == PER_LINUX)
return "s390";
#endif
return NULL;
}
uint64_t physical_memory(void) {
long mem;
/* We return this as uint64_t in case we are running as 32bit
* process on a 64bit kernel with huge amounts of memory */
mem = sysconf(_SC_PHYS_PAGES);
assert(mem > 0);
return (uint64_t) mem * (uint64_t) page_size();
}
int update_reboot_param_file(const char *param) {
int r = 0;
if (param) {
r = write_string_file(REBOOT_PARAM_FILE, param, WRITE_STRING_FILE_CREATE);
if (r < 0)
return log_error_errno(r, "Failed to write reboot param to "REBOOT_PARAM_FILE": %m");
} else
(void) unlink(REBOOT_PARAM_FILE);
return 0;
}
int syslog_parse_priority(const char **p, int *priority, bool with_facility) {
int a = 0, b = 0, c = 0;
int k;
assert(p);
assert(*p);
assert(priority);
if ((*p)[0] != '<')
return 0;
if (!strchr(*p, '>'))
return 0;
if ((*p)[2] == '>') {
c = undecchar((*p)[1]);
k = 3;
} else if ((*p)[3] == '>') {
b = undecchar((*p)[1]);
c = undecchar((*p)[2]);
k = 4;
} else if ((*p)[4] == '>') {
a = undecchar((*p)[1]);
b = undecchar((*p)[2]);
c = undecchar((*p)[3]);
k = 5;
} else
return 0;
if (a < 0 || b < 0 || c < 0 ||
(!with_facility && (a || b || c > 7)))
return 0;
if (with_facility)
*priority = a*100 + b*10 + c;
else
*priority = (*priority & LOG_FACMASK) | c;
*p += k;
return 1;
}
int version(void) {
puts(PACKAGE_STRING "\n"
SYSTEMD_FEATURES);
return 0;
}
bool fdname_is_valid(const char *s) {
const char *p;
/* Validates a name for $LISTEN_FDNAMES. We basically allow
* everything ASCII that's not a control character. Also, as
* special exception the ":" character is not allowed, as we
* use that as field separator in $LISTEN_FDNAMES.
*
* Note that the empty string is explicitly allowed
* here. However, we limit the length of the names to 255
* characters. */
if (!s)
return false;
for (p = s; *p; p++) {
if (*p < ' ')
return false;
if (*p >= 127)
return false;
if (*p == ':')
return false;
}
return p - s < 256;
}
bool oom_score_adjust_is_valid(int oa) {
return oa >= OOM_SCORE_ADJ_MIN && oa <= OOM_SCORE_ADJ_MAX;
}