/***
This file is part of eudev, forked from 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 <assert.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
#include <signal.h>
#include <stdio.h>
#include <syslog.h>
#include <sched.h>
#include <sys/resource.h>
#include <linux/sched.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <sys/ioctl.h>
#include <stdarg.h>
#include <poll.h>
#include <ctype.h>
#include <sys/prctl.h>
#include <sys/utsname.h>
#include <pwd.h>
#include <netinet/ip.h>
#include <linux/kd.h>
#include <dlfcn.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <glob.h>
#include <grp.h>
#include <sys/mman.h>
#include <sys/vfs.h>
#include <linux/magic.h>
#include <limits.h>
#include <locale.h>
#include <libgen.h>
#include "macro.h"
#include "util.h"
#include "ioprio.h"
#include "missing.h"
#include "log.h"
#include "strv.h"
#include "mkdir.h"
#include "path-util.h"
#include "hashmap.h"
#include "fileio.h"
#include "utf8.h"
#include "virt.h"
#include "process-util.h"
#include "random-util.h"
#include "terminal-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 streq_ptr(const char *a, const char *b) {
/* Like streq(), but tries to make sense of NULL pointers */
if (a && b)
return streq(a, b);
if (!a && !b)
return true;
return false;
}
char* endswith(const char *s, const char *postfix) {
size_t sl, pl;
assert(s);
assert(postfix);
sl = strlen(s);
pl = strlen(postfix);
if (pl == 0)
return (char*) s + sl;
if (sl < pl)
return NULL;
if (memcmp(s + sl - pl, postfix, pl) != 0)
return NULL;
return (char*) s + sl - pl;
}
size_t cescape_char(char c, char *buf) {
char * buf_old = buf;
switch (c) {
case '\a':
*(buf++) = '\\';
*(buf++) = 'a';
break;
case '\b':
*(buf++) = '\\';
*(buf++) = 'b';
break;
case '\f':
*(buf++) = '\\';
*(buf++) = 'f';
break;
case '\n':
*(buf++) = '\\';
*(buf++) = 'n';
break;
case '\r':
*(buf++) = '\\';
*(buf++) = 'r';
break;
case '\t':
*(buf++) = '\\';
*(buf++) = 't';
break;
case '\v':
*(buf++) = '\\';
*(buf++) = 'v';
break;
case '\\':
*(buf++) = '\\';
*(buf++) = '\\';
break;
case '"':
*(buf++) = '\\';
*(buf++) = '"';
break;
case '\'':
*(buf++) = '\\';
*(buf++) = '\'';
break;
default:
/* For special chars we prefer octal over
* hexadecimal encoding, simply because glib's
* g_strescape() does the same */
if ((c < ' ') || (c >= 127)) {
*(buf++) = '\\';
*(buf++) = octchar((unsigned char) c >> 6);
*(buf++) = octchar((unsigned char) c >> 3);
*(buf++) = octchar((unsigned char) c);
} else
*(buf++) = c;
break;
}
return buf - buf_old;
}
int close_nointr(int fd) {
assert(fd >= 0);
if (close(fd) >= 0)
return 0;
/*
* Just ignore EINTR; a retry loop is the wrong thing to do on
* Linux.
*
* http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html
* https://bugzilla.gnome.org/show_bug.cgi?id=682819
* http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR
* https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain
*/
if (errno == EINTR)
return 0;
return -errno;
}
int safe_close(int fd) {
/*
* Like close_nointr() but cannot fail. Guarantees errno is
* unchanged. Is a NOP with negative fds passed, and returns
* -1, so that it can be used in this syntax:
*
* fd = safe_close(fd);
*/
if (fd >= 0) {
PROTECT_ERRNO;
/* The kernel might return pretty much any error code
* via close(), but the fd will be closed anyway. The
* only condition we want to check for here is whether
* the fd was invalid at all... */
assert_se(close_nointr(fd) != -EBADF);
}
return -1;
}
void close_many(const int fds[], unsigned n_fd) {
unsigned i;
assert(fds || n_fd <= 0);
for (i = 0; i < n_fd; i++)
safe_close(fds[i]);
}
int unlink_noerrno(const char *path) {
PROTECT_ERRNO;
int r;
r = unlink(path);
if (r < 0)
return -errno;
return 0;
}
int parse_uid(const char *s, uid_t* ret_uid) {
unsigned long ul = 0;
uid_t uid;
int r;
assert(s);
r = safe_atolu(s, &ul);
if (r < 0)
return r;
uid = (uid_t) ul;
if ((unsigned long) uid != ul)
return -ERANGE;
/* Some libc APIs use UID_INVALID as special placeholder */
if (uid == (uid_t) 0xFFFFFFFF)
return -ENXIO;
/* A long time ago UIDs where 16bit, hence explicitly avoid the 16bit -1 too */
if (uid == (uid_t) 0xFFFF)
return -ENXIO;
if (ret_uid)
*ret_uid = uid;
return 0;
}
int safe_atou(const char *s, unsigned *ret_u) {
char *x = NULL;
unsigned long l;
assert(s);
assert(ret_u);
errno = 0;
l = strtoul(s, &x, 0);
if (!x || x == s || *x || errno)
return errno > 0 ? -errno : -EINVAL;
if ((unsigned long) (unsigned) l != l)
return -ERANGE;
*ret_u = (unsigned) l;
return 0;
}
int safe_atoi(const char *s, int *ret_i) {
char *x = NULL;
long l;
assert(s);
assert(ret_i);
errno = 0;
l = strtol(s, &x, 0);
if (!x || x == s || *x || errno)
return errno > 0 ? -errno : -EINVAL;
if ((long) (int) l != l)
return -ERANGE;
*ret_i = (int) l;
return 0;
}
int safe_atollu(const char *s, long long unsigned *ret_llu) {
char *x = NULL;
unsigned long long l;
assert(s);
assert(ret_llu);
errno = 0;
l = strtoull(s, &x, 0);
if (!x || x == s || *x || errno)
return errno ? -errno : -EINVAL;
*ret_llu = l;
return 0;
}
int safe_atolli(const char *s, long long int *ret_lli) {
char *x = NULL;
long long l;
assert(s);
assert(ret_lli);
errno = 0;
l = strtoll(s, &x, 0);
if (!x || x == s || *x || errno)
return errno ? -errno : -EINVAL;
*ret_lli = l;
return 0;
}
static size_t strcspn_escaped(const char *s, const char *reject) {
bool escaped = false;
int n;
for (n=0; s[n]; n++) {
if (escaped)
escaped = false;
else if (s[n] == '\\')
escaped = true;
else if (strchr(reject, s[n]))
break;
}
/* if s ends in \, return index of previous char */
return n - escaped;
}
/* Split a string into words. */
const char* split(const char **state, size_t *l, const char *separator, bool quoted) {
const char *current;
current = *state;
if (!*current) {
assert(**state == '\0');
return NULL;
}
current += strspn(current, separator);
if (!*current) {
*state = current;
return NULL;
}
if (quoted && strchr("\'\"", *current)) {
char quotechars[2] = {*current, '\0'};
*l = strcspn_escaped(current + 1, quotechars);
if (current[*l + 1] == '\0' || current[*l + 1] != quotechars[0] ||
(current[*l + 2] && !strchr(separator, current[*l + 2]))) {
/* right quote missing or garbage at the end */
*state = current;
return NULL;
}
*state = current++ + *l + 2;
} else if (quoted) {
*l = strcspn_escaped(current, separator);
if (current[*l] && !strchr(separator, current[*l])) {
/* unfinished escape */
*state = current;
return NULL;
}
*state = current + *l;
} else {
*l = strcspn(current, separator);
*state = current + *l;
}
return current;
}
char *truncate_nl(char *s) {
assert(s);
s[strcspn(s, NEWLINE)] = 0;
return s;
}
char *strnappend(const char *s, const char *suffix, size_t b) {
size_t a;
char *r;
if (!s && !suffix)
return strdup("");
if (!s)
return strndup(suffix, b);
if (!suffix)
return strdup(s);
assert(s);
assert(suffix);
a = strlen(s);
if (b > ((size_t) -1) - a)
return NULL;
r = new(char, a+b+1);
if (!r)
return NULL;
memcpy(r, s, a);
memcpy(r+a, suffix, b);
r[a+b] = 0;
return r;
}
char *strappend(const char *s, const char *suffix) {
return strnappend(s, suffix, suffix ? strlen(suffix) : 0);
}
int rmdir_parents(const char *path, const char *stop) {
size_t l;
int r = 0;
assert(path);
assert(stop);
l = strlen(path);
/* Skip trailing slashes */
while (l > 0 && path[l-1] == '/')
l--;
while (l > 0) {
char *t;
/* Skip last component */
while (l > 0 && path[l-1] != '/')
l--;
/* Skip trailing slashes */
while (l > 0 && path[l-1] == '/')
l--;
if (l <= 0)
break;
if (!(t = strndup(path, l)))
return -ENOMEM;
if (path_startswith(stop, t)) {
free(t);
return 0;
}
r = rmdir(t);
free(t);
if (r < 0)
if (errno != ENOENT)
return -errno;
}
return 0;
}
char hexchar(int x) {
static const char table[16] = "0123456789abcdef";
return table[x & 15];
}
int unhexchar(char c) {
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
return -EINVAL;
}
char octchar(int x) {
return '0' + (x & 7);
}
int unoctchar(char c) {
if (c >= '0' && c <= '7')
return c - '0';
return -EINVAL;
}
char *cescape(const char *s) {
char *r, *t;
const char *f;
assert(s);
/* Does C style string escaping. May be reversed with
* cunescape(). */
r = new(char, strlen(s)*4 + 1);
if (!r)
return NULL;
for (f = s, t = r; *f; f++)
t += cescape_char(*f, t);
*t = 0;
return r;
}
static int cunescape_one(const char *p, size_t length, char *ret, uint32_t *ret_unicode) {
int r = 1;
assert(p);
assert(*p);
assert(ret);
/* Unescapes C style. Returns the unescaped character in ret,
* unless we encountered a \u sequence in which case the full
* unicode character is returned in ret_unicode, instead. */
if (length != (size_t) -1 && length < 1)
return -EINVAL;
switch (p[0]) {
case 'a':
*ret = '\a';
break;
case 'b':
*ret = '\b';
break;
case 'f':
*ret = '\f';
break;
case 'n':
*ret = '\n';
break;
case 'r':
*ret = '\r';
break;
case 't':
*ret = '\t';
break;
case 'v':
*ret = '\v';
break;
case '\\':
*ret = '\\';
break;
case '"':
*ret = '"';
break;
case '\'':
*ret = '\'';
break;
case 's':
/* This is an extension of the XDG syntax files */
*ret = ' ';
break;
case 'x': {
/* hexadecimal encoding */
int a, b;
if (length != (size_t) -1 && length < 3)
return -EINVAL;
a = unhexchar(p[1]);
if (a < 0)
return -EINVAL;
b = unhexchar(p[2]);
if (b < 0)
return -EINVAL;
/* Don't allow NUL bytes */
if (a == 0 && b == 0)
return -EINVAL;
*ret = (char) ((a << 4U) | b);
r = 3;
break;
}
case 'u': {
/* C++11 style 16bit unicode */
int a[4];
unsigned i;
uint32_t c;
if (length != (size_t) -1 && length < 5)
return -EINVAL;
for (i = 0; i < 4; i++) {
a[i] = unhexchar(p[1 + i]);
if (a[i] < 0)
return a[i];
}
c = ((uint32_t) a[0] << 12U) | ((uint32_t) a[1] << 8U) | ((uint32_t) a[2] << 4U) | (uint32_t) a[3];
/* Don't allow 0 chars */
if (c == 0)
return -EINVAL;
if (c < 128)
*ret = c;
else {
if (!ret_unicode)
return -EINVAL;
*ret = 0;
*ret_unicode = c;
}
r = 5;
break;
}
case 'U': {
/* C++11 style 32bit unicode */
int a[8];
unsigned i;
uint32_t c;
if (length != (size_t) -1 && length < 9)
return -EINVAL;
for (i = 0; i < 8; i++) {
a[i] = unhexchar(p[1 + i]);
if (a[i] < 0)
return a[i];
}
c = ((uint32_t) a[0] << 28U) | ((uint32_t) a[1] << 24U) | ((uint32_t) a[2] << 20U) | ((uint32_t) a[3] << 16U) |
((uint32_t) a[4] << 12U) | ((uint32_t) a[5] << 8U) | ((uint32_t) a[6] << 4U) | (uint32_t) a[7];
/* Don't allow 0 chars */
if (c == 0)
return -EINVAL;
/* Don't allow invalid code points */
if (!unichar_is_valid(c))
return -EINVAL;
if (c < 128)
*ret = c;
else {
if (!ret_unicode)
return -EINVAL;
*ret = 0;
*ret_unicode = c;
}
r = 9;
break;
}
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7': {
/* octal encoding */
int a, b, c;
uint32_t m;
if (length != (size_t) -1 && length < 4)
return -EINVAL;
a = unoctchar(p[0]);
if (a < 0)
return -EINVAL;
b = unoctchar(p[1]);
if (b < 0)
return -EINVAL;
c = unoctchar(p[2]);
if (c < 0)
return -EINVAL;
/* don't allow NUL bytes */
if (a == 0 && b == 0 && c == 0)
return -EINVAL;
/* Don't allow bytes above 255 */
m = ((uint32_t) a << 6U) | ((uint32_t) b << 3U) | (uint32_t) c;
if (m > 255)
return -EINVAL;
*ret = m;
r = 3;
break;
}
default:
return -EINVAL;
}
return r;
}
char *xescape(const char *s, const char *bad) {
char *r, *t;
const char *f;
/* Escapes all chars in bad, in addition to \ and all special
* chars, in \xFF style escaping. May be reversed with
* cunescape(). */
r = new(char, strlen(s) * 4 + 1);
if (!r)
return NULL;
for (f = s, t = r; *f; f++) {
if ((*f < ' ') || (*f >= 127) ||
(*f == '\\') || strchr(bad, *f)) {
*(t++) = '\\';
*(t++) = 'x';
*(t++) = hexchar(*f >> 4);
*(t++) = hexchar(*f);
} else
*(t++) = *f;
}
*t = 0;
return r;
}
_pure_ static bool hidden_file_allow_backup(const char *filename) {
assert(filename);
return
filename[0] == '.' ||
streq(filename, "lost+found") ||
streq(filename, "aquota.user") ||
streq(filename, "aquota.group") ||
endswith(filename, ".rpmnew") ||
endswith(filename, ".rpmsave") ||
endswith(filename, ".rpmorig") ||
endswith(filename, ".dpkg-old") ||
endswith(filename, ".dpkg-new") ||
endswith(filename, ".dpkg-tmp") ||
endswith(filename, ".dpkg-dist") ||
endswith(filename, ".dpkg-bak") ||
endswith(filename, ".dpkg-backup") ||
endswith(filename, ".dpkg-remove") ||
endswith(filename, ".swp");
}
bool hidden_file(const char *filename) {
assert(filename);
if (endswith(filename, "~"))
return true;
return hidden_file_allow_backup(filename);
}
int flush_fd(int fd) {
struct pollfd pollfd = {
.fd = fd,
.events = POLLIN,
};
for (;;) {
char buf[LINE_MAX];
ssize_t l;
int r;
r = poll(&pollfd, 1, 0);
if (r < 0) {
if (errno == EINTR)
continue;
return -errno;
} else if (r == 0)
return 0;
l = read(fd, buf, sizeof(buf));
if (l < 0) {
if (errno == EINTR)
continue;
if (errno == EAGAIN)
return 0;
return -errno;
} else if (l == 0)
return 0;
}
}
ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) {
uint8_t *p = buf;
ssize_t n = 0;
assert(fd >= 0);
assert(buf);
while (nbytes > 0) {
ssize_t k;
k = read(fd, p, nbytes);
if (k < 0) {
if (errno == EINTR)
continue;
if (errno == EAGAIN && do_poll) {
/* We knowingly ignore any return value here,
* and expect that any error/EOF is reported
* via read() */
fd_wait_for_event(fd, POLLIN, USEC_INFINITY);
continue;
}
return n > 0 ? n : -errno;
}
if (k == 0)
return n;
p += k;
nbytes -= k;
n += k;
}
return n;
}
int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll) {
ssize_t n;
n = loop_read(fd, buf, nbytes, do_poll);
if (n < 0)
return n;
if ((size_t) n != nbytes)
return -EIO;
return 0;
}
int loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) {
const uint8_t *p = buf;
assert(fd >= 0);
assert(buf);
errno = 0;
do {
ssize_t k;
k = write(fd, p, nbytes);
if (k < 0) {
if (errno == EINTR)
continue;
if (errno == EAGAIN && do_poll) {
/* We knowingly ignore any return value here,
* and expect that any error/EOF is reported
* via write() */
fd_wait_for_event(fd, POLLOUT, USEC_INFINITY);
continue;
}
return -errno;
}
if (nbytes > 0 && k == 0) /* Can't really happen */
return -EIO;
p += k;
nbytes -= k;
} while (nbytes > 0);
return 0;
}
char* dirname_malloc(const char *path) {
char *d, *dir, *dir2;
d = strdup(path);
if (!d)
return NULL;
dir = dirname(d);
assert(dir);
if (dir != d) {
dir2 = strdup(dir);
free(d);
return dir2;
}
return dir;
}
_pure_ static int is_temporary_fs(struct statfs *s) {
assert(s);
return F_TYPE_EQUAL(s->f_type, TMPFS_MAGIC) ||
F_TYPE_EQUAL(s->f_type, RAMFS_MAGIC);
}
int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid) {
assert(path);
/* Under the assumption that we are running privileged we
* first change the access mode and only then hand out
* ownership to avoid a window where access is too open. */
if (mode != MODE_INVALID)
if (chmod(path, mode) < 0)
return -errno;
if (uid != UID_INVALID || gid != GID_INVALID)
if (chown(path, uid, gid) < 0)
return -errno;
return 0;
}
int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gid, mode_t mode) {
_cleanup_close_ int fd;
int r;
assert(path);
if (parents)
mkdir_parents(path, 0755);
fd = open(path, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY, mode > 0 ? mode : 0644);
if (fd < 0)
return -errno;
if (mode > 0) {
r = fchmod(fd, mode);
if (r < 0)
return -errno;
}
if (uid != UID_INVALID || gid != GID_INVALID) {
r = fchown(fd, uid, gid);
if (r < 0)
return -errno;
}
if (stamp != USEC_INFINITY) {
struct timespec ts[2];
timespec_store(&ts[0], stamp);
ts[1] = ts[0];
r = futimens(fd, ts);
} else
r = futimens(fd, NULL);
if (r < 0)
return -errno;
return 0;
}
int touch(const char *path) {
return touch_file(path, false, USEC_INFINITY, UID_INVALID, GID_INVALID, 0);
}
bool null_or_empty(struct stat *st) {
assert(st);
if (S_ISREG(st->st_mode) && st->st_size <= 0)
return true;
if (S_ISCHR(st->st_mode) || S_ISBLK(st->st_mode))
return true;
return false;
}
int null_or_empty_path(const char *fn) {
struct stat st;
assert(fn);
if (stat(fn, &st) < 0)
return -errno;
return null_or_empty(&st);
}
int null_or_empty_fd(int fd) {
struct stat st;
assert(fd >= 0);
if (fstat(fd, &st) < 0)
return -errno;
return null_or_empty(&st);
}
bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) {
assert(de);
if (de->d_type != DT_REG &&
de->d_type != DT_LNK &&
de->d_type != DT_UNKNOWN)
return false;
if (hidden_file_allow_backup(de->d_name))
return false;
return endswith(de->d_name, suffix);
}
bool nulstr_contains(const char*nulstr, const char *needle) {
const char *i;
if (!nulstr)
return false;
NULSTR_FOREACH(i, nulstr)
if (streq(i, needle))
return true;
return false;
}
static inline int ppoll_fallback(struct pollfd *fds, nfds_t nfds, const struct timespec *timeout_ts, const sigset_t *sigmask) {
int ready, timeout;
sigset_t origmask;
timeout = (timeout_ts == NULL) ? -1 : (timeout_ts->tv_sec * 1000 + timeout_ts->tv_nsec / 1000000);
/* This is racey, but what can we do without ppoll? */
sigprocmask(SIG_SETMASK, sigmask, &origmask);
ready = poll(fds, nfds, timeout);
sigprocmask(SIG_SETMASK, &origmask, NULL);
return ready;
}
int fd_wait_for_event(int fd, int event, usec_t t) {
struct pollfd pollfd = {
.fd = fd,
.events = event,
};
struct timespec ts;
int r;
#if HAVE_DECL_PPOLL
r = ppoll(&pollfd, 1, t == USEC_INFINITY ? NULL : timespec_store(&ts, t), NULL);
#else
/* Fallback path when ppoll() is unavailable */
r = ppoll_fallback(&pollfd, 1, t == USEC_INFINITY ? NULL : timespec_store(&ts, t), NULL);
#endif
if (r < 0)
return -errno;
if (r == 0)
return 0;
return pollfd.revents;
}
int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
FILE *f;
char *t;
int r, fd;
assert(path);
assert(_f);
assert(_temp_path);
r = tempfn_xxxxxx(path, &t);
if (r < 0)
return r;
#if HAVE_DECL_MKOSTEMP
fd = mkostemp_safe(t, O_WRONLY|O_CLOEXEC);
#else
fd = mkstemp_safe(t);
fcntl(fd, F_SETFD, FD_CLOEXEC);
#endif
if (fd < 0) {
free(t);
return -errno;
}
f = fdopen(fd, "we");
if (!f) {
unlink(t);
free(t);
return -errno;
}
*_f = f;
*_temp_path = t;
return 0;
}
int get_user_creds(
const char **username,
uid_t *uid, gid_t *gid,
const char **home,
const char **shell) {
struct passwd *p;
uid_t u;
assert(username);
assert(*username);
/* We enforce some special rules for uid=0: in order to avoid
* NSS lookups for root we hardcode its data. */
if (streq(*username, "root") || streq(*username, "0")) {
*username = "root";
if (uid)
*uid = 0;
if (gid)
*gid = 0;
if (home)
*home = "/root";
if (shell)
*shell = "/bin/sh";
return 0;
}
if (parse_uid(*username, &u) >= 0) {
errno = 0;
p = getpwuid(u);
/* If there are multiple users with the same id, make
* sure to leave $USER to the configured value instead
* of the first occurrence in the database. However if
* the uid was configured by a numeric uid, then let's
* pick the real username from /etc/passwd. */
if (p)
*username = p->pw_name;
} else {
errno = 0;
p = getpwnam(*username);
}
if (!p)
return errno > 0 ? -errno : -ESRCH;
if (uid)
*uid = p->pw_uid;
if (gid)
*gid = p->pw_gid;
if (home)
*home = p->pw_dir;
if (shell)
*shell = p->pw_shell;
return 0;
}
int get_group_creds(const char **groupname, gid_t *gid) {
struct group *g;
gid_t id;
assert(groupname);
/* We enforce some special rules for gid=0: in order to avoid
* NSS lookups for root we hardcode its data. */
if (streq(*groupname, "root") || streq(*groupname, "0")) {
*groupname = "root";
if (gid)
*gid = 0;
return 0;
}
if (parse_gid(*groupname, &id) >= 0) {
errno = 0;
g = getgrgid(id);
if (g)
*groupname = g->gr_name;
} else {
errno = 0;
g = getgrnam(*groupname);
}
if (!g)
return errno > 0 ? -errno : -ESRCH;
if (gid)
*gid = g->gr_gid;
return 0;
}
char *strjoin(const char *x, ...) {
va_list ap;
size_t l;
char *r, *p;
va_start(ap, x);
if (x) {
l = strlen(x);
for (;;) {
const char *t;
size_t n;
t = va_arg(ap, const char *);
if (!t)
break;
n = strlen(t);
if (n > ((size_t) -1) - l) {
va_end(ap);
return NULL;
}
l += n;
}
} else
l = 0;
va_end(ap);
r = new(char, l+1);
if (!r)
return NULL;
if (x) {
p = stpcpy(r, x);
va_start(ap, x);
for (;;) {
const char *t;
t = va_arg(ap, const char *);
if (!t)
break;
p = stpcpy(p, t);
}
va_end(ap);
} else
r[0] = 0;
return r;
}
bool is_main_thread(void) {
static thread_local int cached = 0;
if (_unlikely_(cached == 0))
cached = getpid() == gettid() ? 1 : -1;
return cached > 0;
}
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));
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);
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);
static const char* const rlimit_table[_RLIMIT_MAX] = {
[RLIMIT_CPU] = "LimitCPU",
[RLIMIT_FSIZE] = "LimitFSIZE",
[RLIMIT_DATA] = "LimitDATA",
[RLIMIT_STACK] = "LimitSTACK",
[RLIMIT_CORE] = "LimitCORE",
[RLIMIT_RSS] = "LimitRSS",
[RLIMIT_NOFILE] = "LimitNOFILE",
[RLIMIT_AS] = "LimitAS",
[RLIMIT_NPROC] = "LimitNPROC",
[RLIMIT_MEMLOCK] = "LimitMEMLOCK",
[RLIMIT_LOCKS] = "LimitLOCKS",
[RLIMIT_SIGPENDING] = "LimitSIGPENDING",
[RLIMIT_MSGQUEUE] = "LimitMSGQUEUE",
[RLIMIT_NICE] = "LimitNICE",
[RLIMIT_RTPRIO] = "LimitRTPRIO",
[RLIMIT_RTTIME] = "LimitRTTIME"
};
DEFINE_STRING_TABLE_LOOKUP(rlimit, int);
static const char* const ip_tos_table[] = {
[IPTOS_LOWDELAY] = "low-delay",
[IPTOS_THROUGHPUT] = "throughput",
[IPTOS_RELIABILITY] = "reliability",
[IPTOS_LOWCOST] = "low-cost",
};
DEFINE_STRING_TABLE_LOOKUP_WITH_FALLBACK(ip_tos, int, 0xff);
static const char *const __signal_table[] = {
[SIGHUP] = "HUP",
[SIGINT] = "INT",
[SIGQUIT] = "QUIT",
[SIGILL] = "ILL",
[SIGTRAP] = "TRAP",
[SIGABRT] = "ABRT",
[SIGBUS] = "BUS",
[SIGFPE] = "FPE",
[SIGKILL] = "KILL",
[SIGUSR1] = "USR1",
[SIGSEGV] = "SEGV",
[SIGUSR2] = "USR2",
[SIGPIPE] = "PIPE",
[SIGALRM] = "ALRM",
[SIGTERM] = "TERM",
#ifdef SIGSTKFLT
[SIGSTKFLT] = "STKFLT", /* Linux on SPARC doesn't know SIGSTKFLT */
#endif
[SIGCHLD] = "CHLD",
[SIGCONT] = "CONT",
[SIGSTOP] = "STOP",
[SIGTSTP] = "TSTP",
[SIGTTIN] = "TTIN",
[SIGTTOU] = "TTOU",
[SIGURG] = "URG",
[SIGXCPU] = "XCPU",
[SIGXFSZ] = "XFSZ",
[SIGVTALRM] = "VTALRM",
[SIGPROF] = "PROF",
[SIGWINCH] = "WINCH",
[SIGIO] = "IO",
[SIGPWR] = "PWR",
[SIGSYS] = "SYS"
};
DEFINE_PRIVATE_STRING_TABLE_LOOKUP(__signal, int);
const char *signal_to_string(int signo) {
static thread_local char buf[sizeof("RTMIN+")-1 + DECIMAL_STR_MAX(int) + 1];
const char *name;
name = __signal_to_string(signo);
if (name)
return name;
if (signo >= SIGRTMIN && signo <= SIGRTMAX)
snprintf(buf, sizeof(buf), "RTMIN+%d", signo - SIGRTMIN);
else
snprintf(buf, sizeof(buf), "%d", signo);
return buf;
}
int fd_inc_sndbuf(int fd, size_t n) {
int r, value;
socklen_t l = sizeof(value);
r = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, &l);
if (r >= 0 && l == sizeof(value) && (size_t) value >= n*2)
return 0;
/* If we have the privileges we will ignore the kernel limit. */
value = (int) n;
if (setsockopt(fd, SOL_SOCKET, SO_SNDBUFFORCE, &value, sizeof(value)) < 0)
if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, sizeof(value)) < 0)
return -errno;
return 1;
}
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;
}
bool filename_is_valid(const char *p) {
if (isempty(p))
return false;
if (strchr(p, '/'))
return false;
if (streq(p, "."))
return false;
if (streq(p, ".."))
return false;
if (strlen(p) > FILENAME_MAX)
return false;
return true;
}
/* 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;
}
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;
}
int proc_cmdline(char **ret) {
assert(ret);
if (detect_container(NULL) > 0)
return get_process_cmdline(1, 0, false, ret);
else
return read_one_line_file("/proc/cmdline", ret);
}
int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) {
_cleanup_free_ char *line = NULL;
const char *p;
int r;
assert(parse_item);
r = proc_cmdline(&line);
if (r < 0)
return r;
p = line;
for (;;) {
_cleanup_free_ char *word = NULL;
char *value = NULL;
r = unquote_first_word(&p, &word, UNQUOTE_RELAX);
if (r < 0)
return r;
if (r == 0)
break;
/* Filter out arguments that are intended only for the
* initrd */
if (!in_initrd() && startswith(word, "rd."))
continue;
value = strchr(word, '=');
if (value)
*(value++) = 0;
r = parse_item(word, value);
if (r < 0)
return r;
}
return 0;
}
int getpeercred(int fd, struct ucred *ucred) {
socklen_t n = sizeof(struct ucred);
struct ucred u;
int r;
assert(fd >= 0);
assert(ucred);
r = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &u, &n);
if (r < 0)
return -errno;
if (n != sizeof(struct ucred))
return -EIO;
/* Check if the data is actually useful and not suppressed due
* to namespacing issues */
if (u.pid <= 0)
return -ENODATA;
if (u.uid == UID_INVALID)
return -ENODATA;
if (u.gid == GID_INVALID)
return -ENODATA;
*ucred = u;
return 0;
}
#if HAVE_DECL_MKOSTEMP
/* This is much like like mkostemp() but is subject to umask(). */
int mkostemp_safe(char *pattern, int flags) {
_cleanup_umask_ mode_t u;
int fd;
assert(pattern);
u = umask(077);
fd = mkostemp(pattern, flags);
if (fd < 0)
return -errno;
return fd;
}
#else
/* This is much like like mkstemp() but is subject to umask(). */
int mkstemp_safe(char *pattern) {
_cleanup_umask_ mode_t u;
int fd;
assert(pattern);
u = umask(077);
fd = mkstemp(pattern);
if (fd < 0)
return -errno;
return fd;
}
#endif
int tempfn_xxxxxx(const char *p, char **ret) {
const char *fn;
char *t;
assert(p);
assert(ret);
/*
* Turns this:
* /foo/bar/waldo
*
* Into this:
* /foo/bar/.#waldoXXXXXX
*/
fn = eudev_basename(p);
if (!filename_is_valid(fn))
return -EINVAL;
t = new(char, strlen(p) + 2 + 6 + 1);
if (!t)
return -ENOMEM;
strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), "XXXXXX");
*ret = path_kill_slashes(t);
return 0;
}
int is_dir(const char* path, bool follow) {
struct stat st;
int r;
if (follow)
r = stat(path, &st);
else
r = lstat(path, &st);
if (r < 0)
return -errno;
return !!S_ISDIR(st.st_mode);
}
int unquote_first_word(const char **p, char **ret, UnquoteFlags flags) {
_cleanup_free_ char *s = NULL;
size_t allocated = 0, sz = 0;
int r;
enum {
START,
VALUE,
VALUE_ESCAPE,
SINGLE_QUOTE,
SINGLE_QUOTE_ESCAPE,
DOUBLE_QUOTE,
DOUBLE_QUOTE_ESCAPE,
SPACE,
} state = START;
assert(p);
assert(*p);
assert(ret);
/* Parses the first word of a string, and returns it in
* *ret. Removes all quotes in the process. When parsing fails
* (because of an uneven number of quotes or similar), leaves
* the pointer *p at the first invalid character. */
for (;;) {
char c = **p;
switch (state) {
case START:
if (c == 0)
goto finish;
else if (strchr(WHITESPACE, c))
break;
state = VALUE;
/* fallthrough */
case VALUE:
if (c == 0)
goto finish;
else if (c == '\'')
state = SINGLE_QUOTE;
else if (c == '\\')
state = VALUE_ESCAPE;
else if (c == '\"')
state = DOUBLE_QUOTE;
else if (strchr(WHITESPACE, c))
state = SPACE;
else {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
s[sz++] = c;
}
break;
case VALUE_ESCAPE:
if (c == 0) {
if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
if (!GREEDY_REALLOC(s, allocated, sz+7))
return -ENOMEM;
if (flags & UNQUOTE_CUNESCAPE) {
uint32_t u;
r = cunescape_one(*p, (size_t) -1, &c, &u);
if (r < 0)
return -EINVAL;
(*p) += r - 1;
if (c != 0)
s[sz++] = c; /* normal explicit char */
else
sz += utf8_encode_unichar(s + sz, u); /* unicode chars we'll encode as utf8 */
} else
s[sz++] = c;
state = VALUE;
break;
case SINGLE_QUOTE:
if (c == 0) {
if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
} else if (c == '\'')
state = VALUE;
else if (c == '\\')
state = SINGLE_QUOTE_ESCAPE;
else {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
s[sz++] = c;
}
break;
case SINGLE_QUOTE_ESCAPE:
if (c == 0) {
if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
if (!GREEDY_REALLOC(s, allocated, sz+7))
return -ENOMEM;
if (flags & UNQUOTE_CUNESCAPE) {
uint32_t u;
r = cunescape_one(*p, (size_t) -1, &c, &u);
if (r < 0)
return -EINVAL;
(*p) += r - 1;
if (c != 0)
s[sz++] = c;
else
sz += utf8_encode_unichar(s + sz, u);
} else
s[sz++] = c;
state = SINGLE_QUOTE;
break;
case DOUBLE_QUOTE:
if (c == 0)
return -EINVAL;
else if (c == '\"')
state = VALUE;
else if (c == '\\')
state = DOUBLE_QUOTE_ESCAPE;
else {
if (!GREEDY_REALLOC(s, allocated, sz+2))
return -ENOMEM;
s[sz++] = c;
}
break;
case DOUBLE_QUOTE_ESCAPE:
if (c == 0) {
if (flags & UNQUOTE_RELAX)
goto finish;
return -EINVAL;
}
if (!GREEDY_REALLOC(s, allocated, sz+7))
return -ENOMEM;
if (flags & UNQUOTE_CUNESCAPE) {
uint32_t u;
r = cunescape_one(*p, (size_t) -1, &c, &u);
if (r < 0)
return -EINVAL;
(*p) += r - 1;
if (c != 0)
s[sz++] = c;
else
sz += utf8_encode_unichar(s + sz, u);
} else
s[sz++] = c;
state = DOUBLE_QUOTE;
break;
case SPACE:
if (c == 0)
goto finish;
if (!strchr(WHITESPACE, c))
goto finish;
break;
}
(*p) ++;
}
finish:
if (!s) {
*ret = NULL;
return 0;
}
s[sz] = 0;
*ret = s;
s = NULL;
return 1;
}
void cmsg_close_all(struct msghdr *mh) {
struct cmsghdr *cmsg;
assert(mh);
for (cmsg = CMSG_FIRSTHDR(mh); cmsg; cmsg = CMSG_NXTHDR(mh, cmsg))
if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS)
close_many((int*) CMSG_DATA(cmsg), (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int));
}
const char *eudev_basename(const char *filename) {
const char *p = strrchr(filename, '/');
if (p)
return p + 1;
return filename;
}