summaryrefslogtreecommitdiff
path: root/src/basic/user-util.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/basic/user-util.c')
-rw-r--r--src/basic/user-util.c636
1 files changed, 0 insertions, 636 deletions
diff --git a/src/basic/user-util.c b/src/basic/user-util.c
deleted file mode 100644
index de6c93056e..0000000000
--- a/src/basic/user-util.c
+++ /dev/null
@@ -1,636 +0,0 @@
-/***
- 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 <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 "formats-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 "utf8.h"
-
-bool uid_is_valid(uid_t uid) {
-
- /* Some libc APIs use UID_INVALID as special placeholder */
- if (uid == (uid_t) UINT32_C(0xFFFFFFFF))
- return false;
-
- /* A long time ago UIDs where 16bit, hence explicitly avoid the 16bit -1 too */
- if (uid == (uid_t) UINT32_C(0xFFFF))
- return false;
-
- return true;
-}
-
-int parse_uid(const char *s, uid_t *ret) {
- uint32_t uid = 0;
- int r;
-
- assert(s);
-
- assert_cc(sizeof(uid_t) == sizeof(uint32_t));
- r = safe_atou32(s, &uid);
- if (r < 0)
- return r;
-
- if (!uid_is_valid(uid))
- return -ENXIO; /* we return ENXIO instead of EINVAL
- * here, to make it easy to distuingish
- * invalid numeric uids from invalid
- * strings. */
-
- if (ret)
- *ret = uid;
-
- return 0;
-}
-
-char* getlogname_malloc(void) {
- uid_t uid;
- struct stat st;
-
- if (isatty(STDIN_FILENO) && fstat(STDIN_FILENO, &st) >= 0)
- uid = st.st_uid;
- else
- uid = getuid();
-
- return uid_to_name(uid);
-}
-
-char *getusername_malloc(void) {
- const char *e;
-
- e = getenv("USER");
- if (e)
- return strdup(e);
-
- return uid_to_name(getuid());
-}
-
-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) {
- if (!uid_is_valid(p->pw_uid))
- return -EBADMSG;
-
- *uid = p->pw_uid;
- }
-
- if (gid) {
- if (!gid_is_valid(p->pw_gid))
- return -EBADMSG;
-
- *gid = p->pw_gid;
- }
-
- if (home)
- *home = p->pw_dir;
-
- if (shell)
- *shell = p->pw_shell;
-
- return 0;
-}
-
-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;
-
- 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) {
- if (!gid_is_valid(g->gr_gid))
- return -EBADMSG;
-
- *gid = g->gr_gid;
- }
-
- return 0;
-}
-
-char* uid_to_name(uid_t uid) {
- char *ret;
- int r;
-
- /* Shortcut things to avoid NSS lookups */
- if (uid == 0)
- return strdup("root");
-
- if (uid_is_valid(uid)) {
- long bufsize;
-
- bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);
- if (bufsize <= 0)
- bufsize = 4096;
-
- for (;;) {
- struct passwd pwbuf, *pw = NULL;
- _cleanup_free_ char *buf = NULL;
-
- buf = malloc(bufsize);
- if (!buf)
- return NULL;
-
- r = getpwuid_r(uid, &pwbuf, buf, (size_t) bufsize, &pw);
- if (r == 0 && pw)
- return strdup(pw->pw_name);
- if (r != ERANGE)
- break;
-
- bufsize *= 2;
- }
- }
-
- if (asprintf(&ret, UID_FMT, uid) < 0)
- return NULL;
-
- return ret;
-}
-
-char* gid_to_name(gid_t gid) {
- char *ret;
- int r;
-
- if (gid == 0)
- return strdup("root");
-
- if (gid_is_valid(gid)) {
- long bufsize;
-
- bufsize = sysconf(_SC_GETGR_R_SIZE_MAX);
- if (bufsize <= 0)
- bufsize = 4096;
-
- for (;;) {
- struct group grbuf, *gr = NULL;
- _cleanup_free_ char *buf = NULL;
-
- buf = malloc(bufsize);
- if (!buf)
- return NULL;
-
- r = getgrgid_r(gid, &grbuf, buf, (size_t) bufsize, &gr);
- if (r == 0 && gr)
- return strdup(gr->gr_name);
- if (r != ERANGE)
- break;
-
- bufsize *= 2;
- }
- }
-
- if (asprintf(&ret, GID_FMT, gid) < 0)
- return NULL;
-
- return ret;
-}
-
-int in_gid(gid_t gid) {
- gid_t *gids;
- int ngroups_max, r, i;
-
- if (getgid() == gid)
- return 1;
-
- if (getegid() == gid)
- return 1;
-
- if (!gid_is_valid(gid))
- return -EINVAL;
-
- ngroups_max = sysconf(_SC_NGROUPS_MAX);
- assert(ngroups_max > 0);
-
- gids = alloca(sizeof(gid_t) * ngroups_max);
-
- r = getgroups(ngroups_max, gids);
- if (r < 0)
- return -errno;
-
- for (i = 0; i < r; i++)
- if (gids[i] == gid)
- return 1;
-
- return 0;
-}
-
-int in_group(const char *name) {
- int r;
- gid_t gid;
-
- r = get_group_creds(&name, &gid);
- if (r < 0)
- return r;
-
- return in_gid(gid);
-}
-
-int get_home_dir(char **_h) {
- struct passwd *p;
- const char *e;
- char *h;
- uid_t u;
-
- assert(_h);
-
- /* Take the user specified one */
- e = secure_getenv("HOME");
- if (e && path_is_absolute(e)) {
- h = strdup(e);
- if (!h)
- return -ENOMEM;
-
- *_h = h;
- return 0;
- }
-
- /* Hardcode home directory for root to avoid NSS */
- u = getuid();
- if (u == 0) {
- h = strdup("/root");
- if (!h)
- return -ENOMEM;
-
- *_h = h;
- return 0;
- }
-
- /* Check the database... */
- errno = 0;
- p = getpwuid(u);
- if (!p)
- return errno > 0 ? -errno : -ESRCH;
-
- if (!path_is_absolute(p->pw_dir))
- return -EINVAL;
-
- h = strdup(p->pw_dir);
- if (!h)
- return -ENOMEM;
-
- *_h = h;
- return 0;
-}
-
-int get_shell(char **_s) {
- struct passwd *p;
- const char *e;
- char *s;
- uid_t u;
-
- assert(_s);
-
- /* Take the user specified one */
- e = getenv("SHELL");
- if (e) {
- s = strdup(e);
- if (!s)
- return -ENOMEM;
-
- *_s = s;
- return 0;
- }
-
- /* Hardcode home directory for root to avoid NSS */
- u = getuid();
- if (u == 0) {
- s = strdup("/bin/sh");
- if (!s)
- return -ENOMEM;
-
- *_s = s;
- return 0;
- }
-
- /* Check the database... */
- errno = 0;
- p = getpwuid(u);
- if (!p)
- return errno > 0 ? -errno : -ESRCH;
-
- if (!path_is_absolute(p->pw_shell))
- return -EINVAL;
-
- s = strdup(p->pw_shell);
- if (!s)
- return -ENOMEM;
-
- *_s = s;
- return 0;
-}
-
-int reset_uid_gid(void) {
- int r;
-
- r = maybe_setgroups(0, NULL);
- if (r < 0)
- return r;
-
- if (setresgid(0, 0, 0) < 0)
- return -errno;
-
- if (setresuid(0, 0, 0) < 0)
- return -errno;
-
- return 0;
-}
-
-int take_etc_passwd_lock(const char *root) {
-
- struct flock flock = {
- .l_type = F_WRLCK,
- .l_whence = SEEK_SET,
- .l_start = 0,
- .l_len = 0,
- };
-
- const char *path;
- int fd, r;
-
- /* This is roughly the same as lckpwdf(), but not as awful. We
- * don't want to use alarm() and signals, hence we implement
- * our own trivial version of this.
- *
- * Note that shadow-utils also takes per-database locks in
- * addition to lckpwdf(). However, we don't given that they
- * 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. */
-
- if (root)
- path = prefix_roota(root, "/etc/.pwd.lock");
- else
- path = "/etc/.pwd.lock";
-
- fd = open(path, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0600);
- if (fd < 0)
- return -errno;
-
- r = fcntl(fd, F_SETLKW, &flock);
- if (r < 0) {
- safe_close(fd);
- return -errno;
- }
-
- return fd;
-}
-
-bool valid_user_group_name(const char *u) {
- const char *i;
- long sz;
-
- /* Checks if the specified name is a valid user/group name. */
-
- 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;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 13:42:48 +0000