-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
/***
This file is part of systemd.
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+#include <alloca.h>
+#include <errno.h>
+#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <utmp.h>
#include "alloc-util.h"
#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
#include "macro.h"
+#include "missing.h"
#include "parse-util.h"
#include "path-util.h"
#include "string-util.h"
+#include "strv.h"
#include "user-util.h"
-#include "util.h"
+#include "utf8.h"
bool uid_is_valid(uid_t uid) {
+ /* Also see POSIX IEEE Std 1003.1-2008, 2016 Edition, 3.436. */
+
/* Some libc APIs use UID_INVALID as special placeholder */
if (uid == (uid_t) UINT32_C(0xFFFFFFFF))
return false;
if (!uid_is_valid(uid))
return -ENXIO; /* we return ENXIO instead of EINVAL
* here, to make it easy to distuingish
- * invalid numeric uids invalid
+ * invalid numeric uids from invalid
* strings. */
if (ret)
return uid_to_name(uid);
}
+#if 0 /// UNNEEDED by elogind
char *getusername_malloc(void) {
const char *e;
return uid_to_name(getuid());
}
+#endif // 0
int get_user_creds(
const char **username,
return 0;
}
+#if 0 /// UNNEEDED by elogind
+int get_user_creds_clean(
+ const char **username,
+ uid_t *uid, gid_t *gid,
+ const char **home,
+ const char **shell) {
+
+ int r;
+
+ /* Like get_user_creds(), but resets home/shell to NULL if they don't contain anything relevant. */
+
+ r = get_user_creds(username, uid, gid, home, shell);
+ if (r < 0)
+ return r;
+
+ if (shell &&
+ (isempty(*shell) || PATH_IN_SET(*shell,
+ "/bin/nologin",
+ "/sbin/nologin",
+ "/usr/bin/nologin",
+ "/usr/sbin/nologin")))
+ *shell = NULL;
+
+ if (home &&
+ (isempty(*home) || path_equal(*home, "/")))
+ *home = NULL;
+
+ return 0;
+}
+
int get_group_creds(const char **groupname, gid_t *gid) {
struct group *g;
gid_t id;
return 0;
}
+#endif // 0
char* uid_to_name(uid_t uid) {
char *ret;
return ret;
}
+#if 0 /// UNNEEDED by elogind
int in_gid(gid_t gid) {
gid_t *gids;
int ngroups_max, r, i;
*_s = s;
return 0;
}
+#endif // 0
int reset_uid_gid(void) {
+ int r;
- if (setgroups(0, NULL) < 0)
- return -errno;
+ r = maybe_setgroups(0, NULL);
+ if (r < 0)
+ return r;
if (setresgid(0, 0, 0) < 0)
return -errno;
return 0;
}
+#if 0 /// UNNEEDED by elogind
int take_etc_passwd_lock(const char *root) {
struct flock flock = {
*
* Note that shadow-utils also takes per-database locks in
* addition to lckpwdf(). However, we don't given that they
- * are redundant as they they invoke lckpwdf() first and keep
+ * are redundant as they invoke lckpwdf() first and keep
* it during everything they do. The per-database locks are
* awfully racy, and thus we just won't do them. */
return fd;
}
+#endif // 0
+
+bool valid_user_group_name(const char *u) {
+ const char *i;
+ long sz;
+
+ /* Checks if the specified name is a valid user/group name. Also see POSIX IEEE Std 1003.1-2008, 2016 Edition,
+ * 3.437. We are a bit stricter here however. Specifically we deviate from POSIX rules:
+ *
+ * - We don't allow any dots (this would break chown syntax which permits dots as user/group name separator)
+ * - We require that names fit into the appropriate utmp field
+ * - We don't allow empty user names
+ *
+ * Note that other systems are even more restrictive, and don't permit underscores or uppercase characters.
+ */
+
+ if (isempty(u))
+ return false;
+
+ if (!(u[0] >= 'a' && u[0] <= 'z') &&
+ !(u[0] >= 'A' && u[0] <= 'Z') &&
+ u[0] != '_')
+ return false;
+
+ for (i = u+1; *i; i++) {
+ if (!(*i >= 'a' && *i <= 'z') &&
+ !(*i >= 'A' && *i <= 'Z') &&
+ !(*i >= '0' && *i <= '9') &&
+ *i != '_' &&
+ *i != '-')
+ return false;
+ }
+
+ sz = sysconf(_SC_LOGIN_NAME_MAX);
+ assert_se(sz > 0);
+
+ if ((size_t) (i-u) > (size_t) sz)
+ return false;
+
+ if ((size_t) (i-u) > UT_NAMESIZE - 1)
+ return false;
+
+ return true;
+}
+
+bool valid_user_group_name_or_id(const char *u) {
+
+ /* Similar as above, but is also fine with numeric UID/GID specifications, as long as they are in the right
+ * range, and not the invalid user ids. */
+
+ if (isempty(u))
+ return false;
+
+ if (valid_user_group_name(u))
+ return true;
+
+ return parse_uid(u, NULL) >= 0;
+}
+
+bool valid_gecos(const char *d) {
+
+ if (!d)
+ return false;
+
+ if (!utf8_is_valid(d))
+ return false;
+
+ if (string_has_cc(d, NULL))
+ return false;
+
+ /* Colons are used as field separators, and hence not OK */
+ if (strchr(d, ':'))
+ return false;
+
+ return true;
+}
+
+bool valid_home(const char *p) {
+
+ if (isempty(p))
+ return false;
+
+ if (!utf8_is_valid(p))
+ return false;
+
+ if (string_has_cc(p, NULL))
+ return false;
+
+ if (!path_is_absolute(p))
+ return false;
+
+ if (!path_is_safe(p))
+ return false;
+
+ /* Colons are used as field separators, and hence not OK */
+ if (strchr(p, ':'))
+ return false;
+
+ return true;
+}
+
+int maybe_setgroups(size_t size, const gid_t *list) {
+ int r;
+
+ /* Check if setgroups is allowed before we try to drop all the auxiliary groups */
+ if (size == 0) { /* Dropping all aux groups? */
+ _cleanup_free_ char *setgroups_content = NULL;
+ bool can_setgroups;
+
+ r = read_one_line_file("/proc/self/setgroups", &setgroups_content);
+ if (r == -ENOENT)
+ /* Old kernels don't have /proc/self/setgroups, so assume we can use setgroups */
+ can_setgroups = true;
+ else if (r < 0)
+ return r;
+ else
+ can_setgroups = streq(setgroups_content, "allow");
+
+ if (!can_setgroups) {
+ log_debug("Skipping setgroups(), /proc/self/setgroups is set to 'deny'");
+ return 0;
+ }
+ }
+
+ if (setgroups(size, list) < 0)
+ return -errno;
+
+ return 0;
+}
~ianmdlvl / elogind.git / blobdiff