summaryrefslogtreecommitdiffstats
path: root/src/chpasswd.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/chpasswd.c')
-rw-r--r--src/chpasswd.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/src/chpasswd.c b/src/chpasswd.c
new file mode 100644
index 0000000..48d5178
--- /dev/null
+++ b/src/chpasswd.c
@@ -0,0 +1,685 @@
+/*
+ * SPDX-FileCopyrightText: 1990 - 1994, Julianne Frances Haugh
+ * SPDX-FileCopyrightText: 1996 - 2000, Marek Michałkiewicz
+ * SPDX-FileCopyrightText: 2000 - 2006, Tomasz Kłoczko
+ * SPDX-FileCopyrightText: 2007 - 2011, Nicolas François
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <config.h>
+
+#ident "$Id$"
+
+#include <fcntl.h>
+#include <getopt.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef USE_PAM
+#include "pam_defs.h"
+#endif /* USE_PAM */
+#include "defines.h"
+#include "nscd.h"
+#include "sssd.h"
+#include "getdef.h"
+#include "prototypes.h"
+#include "pwio.h"
+#include "shadowio.h"
+/*@-exitarg@*/
+#include "exitcodes.h"
+#include "shadowlog.h"
+
+#define IS_CRYPT_METHOD(str) ((crypt_method != NULL && strcmp(crypt_method, str) == 0) ? true : false)
+
+/*
+ * Global variables
+ */
+const char *Prog;
+static bool eflg = false;
+static bool md5flg = false;
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+static bool sflg = false;
+#endif
+
+static /*@null@*//*@observer@*/const char *crypt_method = NULL;
+#define cflg (NULL != crypt_method)
+#ifdef USE_SHA_CRYPT
+static long sha_rounds = 5000;
+#endif
+#ifdef USE_BCRYPT
+static long bcrypt_rounds = 13;
+#endif
+#ifdef USE_YESCRYPT
+static long yescrypt_cost = 5;
+#endif
+
+static bool is_shadow_pwd;
+static bool pw_locked = false;
+static bool spw_locked = false;
+
+/* local function prototypes */
+static void fail_exit (int code);
+static /*@noreturn@*/void usage (int status);
+static void process_flags (int argc, char **argv);
+static void check_flags (void);
+static void check_perms (void);
+static void open_files (void);
+static void close_files (void);
+
+/*
+ * fail_exit - exit with a failure code after unlocking the files
+ */
+static void fail_exit (int code)
+{
+ if (pw_locked) {
+ if (pw_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, pw_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", pw_dbname ()));
+ /* continue */
+ }
+ }
+
+ if (spw_locked) {
+ if (spw_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, spw_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", spw_dbname ()));
+ /* continue */
+ }
+ }
+
+ exit (code);
+}
+
+/*
+ * usage - display usage message and exit
+ */
+static /*@noreturn@*/void usage (int status)
+{
+ FILE *usageout = (E_SUCCESS != status) ? stderr : stdout;
+ (void) fprintf (usageout,
+ _("Usage: %s [options]\n"
+ "\n"
+ "Options:\n"),
+ Prog);
+ (void) fprintf (usageout,
+ _(" -c, --crypt-method METHOD the crypt method (one of %s)\n"),
+ "NONE DES MD5"
+#if defined(USE_SHA_CRYPT)
+ " SHA256 SHA512"
+#endif
+#if defined(USE_BCRYPT)
+ " BCRYPT"
+#endif
+#if defined(USE_YESCRYPT)
+ " YESCRYPT"
+#endif
+ );
+ (void) fputs (_(" -e, --encrypted supplied passwords are encrypted\n"), usageout);
+ (void) fputs (_(" -h, --help display this help message and exit\n"), usageout);
+ (void) fputs (_(" -m, --md5 encrypt the clear text password using\n"
+ " the MD5 algorithm\n"),
+ usageout);
+ (void) fputs (_(" -R, --root CHROOT_DIR directory to chroot into\n"), usageout);
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ (void) fputs (_(" -s, --sha-rounds number of rounds for the SHA, BCRYPT\n"
+ " or YESCRYPT crypt algorithms\n"),
+ usageout);
+#endif /* USE_SHA_CRYPT || USE_BCRYPT || USE_YESCRYPT */
+ (void) fputs ("\n", usageout);
+
+ exit (status);
+}
+
+/*
+ * process_flags - parse the command line options
+ *
+ * It will not return if an error is encountered.
+ */
+static void process_flags (int argc, char **argv)
+{
+ int c;
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ int bad_s;
+#endif /* USE_SHA_CRYPT || USE_BCRYPT || USE_YESCRYPT */
+ static struct option long_options[] = {
+ {"crypt-method", required_argument, NULL, 'c'},
+ {"encrypted", no_argument, NULL, 'e'},
+ {"help", no_argument, NULL, 'h'},
+ {"md5", no_argument, NULL, 'm'},
+ {"root", required_argument, NULL, 'R'},
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ {"sha-rounds", required_argument, NULL, 's'},
+#endif /* USE_SHA_CRYPT || USE_BCRYPT || USE_YESCRYPT */
+ {NULL, 0, NULL, '\0'}
+ };
+
+ while ((c = getopt_long (argc, argv,
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ "c:ehmR:s:",
+#else
+ "c:ehmR:",
+#endif
+ long_options, NULL)) != -1) {
+ switch (c) {
+ case 'c':
+ crypt_method = optarg;
+ break;
+ case 'e':
+ eflg = true;
+ break;
+ case 'h':
+ usage (E_SUCCESS);
+ /*@notreached@*/break;
+ case 'm':
+ md5flg = true;
+ break;
+ case 'R': /* no-op, handled in process_root_flag () */
+ break;
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ case 's':
+ sflg = true;
+ bad_s = 0;
+#if defined(USE_SHA_CRYPT)
+ if ((IS_CRYPT_METHOD("SHA256") || IS_CRYPT_METHOD("SHA512"))
+ && (0 == getlong(optarg, &sha_rounds))) {
+ bad_s = 1;
+ }
+#endif /* USE_SHA_CRYPT */
+#if defined(USE_BCRYPT)
+ if (IS_CRYPT_METHOD("BCRYPT")
+ && (0 == getlong(optarg, &bcrypt_rounds))) {
+ bad_s = 1;
+ }
+#endif /* USE_BCRYPT */
+#if defined(USE_YESCRYPT)
+ if (IS_CRYPT_METHOD("YESCRYPT")
+ && (0 == getlong(optarg, &yescrypt_cost))) {
+ bad_s = 1;
+ }
+#endif /* USE_YESCRYPT */
+ if (bad_s != 0) {
+ fprintf (stderr,
+ _("%s: invalid numeric argument '%s'\n"),
+ Prog, optarg);
+ usage (E_USAGE);
+ }
+ break;
+#endif /* USE_SHA_CRYPT || USE_BCRYPT || USE_YESCRYPT */
+
+ default:
+ usage (E_USAGE);
+ /*@notreached@*/break;
+ }
+ }
+
+ /* validate options */
+ check_flags ();
+}
+
+/*
+ * check_flags - check flags and parameters consistency
+ *
+ * It will not return if an error is encountered.
+ */
+static void check_flags (void)
+{
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ if (sflg && !cflg) {
+ fprintf (stderr,
+ _("%s: %s flag is only allowed with the %s flag\n"),
+ Prog, "-s", "-c");
+ usage (E_USAGE);
+ }
+#endif
+
+ if ((eflg && (md5flg || cflg)) ||
+ (md5flg && cflg)) {
+ fprintf (stderr,
+ _("%s: the -c, -e, and -m flags are exclusive\n"),
+ Prog);
+ usage (E_USAGE);
+ }
+
+ if (cflg) {
+ if ((!IS_CRYPT_METHOD("DES"))
+ &&(!IS_CRYPT_METHOD("MD5"))
+ &&(!IS_CRYPT_METHOD("NONE"))
+#ifdef USE_SHA_CRYPT
+ &&(!IS_CRYPT_METHOD("SHA256"))
+ &&(!IS_CRYPT_METHOD("SHA512"))
+#endif /* USE_SHA_CRYPT */
+#ifdef USE_BCRYPT
+ &&(!IS_CRYPT_METHOD("BCRYPT"))
+#endif /* USE_BCRYPT */
+#ifdef USE_YESCRYPT
+ &&(!IS_CRYPT_METHOD("YESCRYPT"))
+#endif /* USE_YESCRYPT */
+ ) {
+ fprintf (stderr,
+ _("%s: unsupported crypt method: %s\n"),
+ Prog, crypt_method);
+ usage (E_USAGE);
+ }
+ }
+}
+
+/*
+ * check_perms - check if the caller is allowed to add a group
+ *
+ * With PAM support, the setuid bit can be set on chpasswd to allow
+ * non-root users to groups.
+ * Without PAM support, only users who can write in the group databases
+ * can add groups.
+ *
+ * It will not return if the user is not allowed.
+ */
+static void check_perms (void)
+{
+#ifdef USE_PAM
+#ifdef ACCT_TOOLS_SETUID
+ /* If chpasswd uses PAM and is SUID, check the permissions,
+ * otherwise, the permissions are enforced by the access to the
+ * passwd and shadow files.
+ */
+ pam_handle_t *pamh = NULL;
+ int retval;
+ struct passwd *pampw;
+
+ pampw = getpwuid (getuid ()); /* local, no need for xgetpwuid */
+ if (NULL == pampw) {
+ fprintf (stderr,
+ _("%s: Cannot determine your user name.\n"),
+ Prog);
+ exit (1);
+ }
+
+ retval = pam_start ("chpasswd", pampw->pw_name, &conv, &pamh);
+
+ if (PAM_SUCCESS == retval) {
+ retval = pam_authenticate (pamh, 0);
+ }
+
+ if (PAM_SUCCESS == retval) {
+ retval = pam_acct_mgmt (pamh, 0);
+ }
+
+ if (PAM_SUCCESS != retval) {
+ fprintf (stderr, _("%s: PAM: %s\n"),
+ Prog, pam_strerror (pamh, retval));
+ SYSLOG((LOG_ERR, "%s", pam_strerror (pamh, retval)));
+ if (NULL != pamh) {
+ (void) pam_end (pamh, retval);
+ }
+ exit (1);
+ }
+ (void) pam_end (pamh, retval);
+#endif /* ACCT_TOOLS_SETUID */
+#endif /* USE_PAM */
+}
+
+/*
+ * open_files - lock and open the password databases
+ */
+static void open_files (void)
+{
+ /*
+ * Lock the password file and open it for reading and writing. This
+ * will bring all of the entries into memory where they may be updated.
+ */
+ if (pw_lock () == 0) {
+ fprintf (stderr,
+ _("%s: cannot lock %s; try again later.\n"),
+ Prog, pw_dbname ());
+ fail_exit (1);
+ }
+ pw_locked = true;
+ if (pw_open (O_CREAT | O_RDWR) == 0) {
+ fprintf (stderr,
+ _("%s: cannot open %s\n"), Prog, pw_dbname ());
+ fail_exit (1);
+ }
+
+ /* Do the same for the shadowed database, if it exist */
+ if (is_shadow_pwd) {
+ if (spw_lock () == 0) {
+ fprintf (stderr,
+ _("%s: cannot lock %s; try again later.\n"),
+ Prog, spw_dbname ());
+ fail_exit (1);
+ }
+ spw_locked = true;
+ if (spw_open (O_CREAT | O_RDWR) == 0) {
+ fprintf (stderr,
+ _("%s: cannot open %s\n"),
+ Prog, spw_dbname ());
+ fail_exit (1);
+ }
+ }
+}
+
+/*
+ * close_files - close and unlock the password databases
+ */
+static void close_files (void)
+{
+ if (is_shadow_pwd) {
+ if (spw_close () == 0) {
+ fprintf (stderr,
+ _("%s: failure while writing changes to %s\n"),
+ Prog, spw_dbname ());
+ SYSLOG ((LOG_ERR, "failure while writing changes to %s", spw_dbname ()));
+ fail_exit (1);
+ }
+ if (spw_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, spw_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", spw_dbname ()));
+ /* continue */
+ }
+ spw_locked = false;
+ }
+
+ if (pw_close () == 0) {
+ fprintf (stderr,
+ _("%s: failure while writing changes to %s\n"),
+ Prog, pw_dbname ());
+ SYSLOG ((LOG_ERR, "failure while writing changes to %s", pw_dbname ()));
+ fail_exit (1);
+ }
+ if (pw_unlock () == 0) {
+ fprintf (stderr, _("%s: failed to unlock %s\n"), Prog, pw_dbname ());
+ SYSLOG ((LOG_ERR, "failed to unlock %s", pw_dbname ()));
+ /* continue */
+ }
+ pw_locked = false;
+}
+
+static const char *get_salt(void)
+{
+ void *arg = NULL;
+
+ if (eflg || IS_CRYPT_METHOD("NONE")) {
+ return NULL;
+ }
+
+ if (md5flg) {
+ crypt_method = "MD5";
+ }
+#if defined(USE_SHA_CRYPT) || defined(USE_BCRYPT) || defined(USE_YESCRYPT)
+ if (sflg) {
+#if defined(USE_SHA_CRYPT)
+ if (IS_CRYPT_METHOD("SHA256") || IS_CRYPT_METHOD("SHA512")) {
+ arg = &sha_rounds;
+ }
+#endif /* USE_SHA_CRYPT */
+#if defined(USE_BCRYPT)
+ if (IS_CRYPT_METHOD("BCRYPT")) {
+ arg = &bcrypt_rounds;
+ }
+#endif /* USE_BCRYPT */
+#if defined(USE_YESCRYPT)
+ if (IS_CRYPT_METHOD("YESCRYPT")) {
+ arg = &yescrypt_cost;
+ }
+#endif /* USE_YESCRYPT */
+ }
+#endif
+ return crypt_make_salt (crypt_method, arg);
+}
+
+int main (int argc, char **argv)
+{
+ char buf[BUFSIZ];
+ char *name;
+ char *newpwd;
+ char *cp;
+ const char *salt;
+
+#ifdef USE_PAM
+ bool use_pam = true;
+#endif /* USE_PAM */
+
+ int errors = 0;
+ int line = 0;
+
+ Prog = Basename (argv[0]);
+ log_set_progname(Prog);
+ log_set_logfd(stderr);
+
+ (void) setlocale (LC_ALL, "");
+ (void) bindtextdomain (PACKAGE, LOCALEDIR);
+ (void) textdomain (PACKAGE);
+
+ process_flags (argc, argv);
+
+ salt = get_salt();
+ process_root_flag ("-R", argc, argv);
+
+#ifdef USE_PAM
+ if (md5flg || eflg || cflg) {
+ use_pam = false;
+ }
+#endif /* USE_PAM */
+
+ OPENLOG ("chpasswd");
+
+ check_perms ();
+
+#ifdef USE_PAM
+ if (!use_pam)
+#endif /* USE_PAM */
+ {
+ is_shadow_pwd = spw_file_present ();
+
+ open_files ();
+ }
+
+ /*
+ * Read each line, separating the user name from the password. The
+ * password entry for each user will be looked up in the appropriate
+ * file (shadow or passwd) and the password changed. For shadow
+ * files the last change date is set directly, for passwd files the
+ * last change date is set in the age only if aging information is
+ * present.
+ */
+ while (fgets (buf, (int) sizeof buf, stdin) != (char *) 0) {
+ line++;
+ cp = strrchr (buf, '\n');
+ if (NULL != cp) {
+ *cp = '\0';
+ } else {
+ if (feof (stdin) == 0) {
+
+ // Drop all remaining characters on this line.
+ while (fgets (buf, (int) sizeof buf, stdin) != (char *) 0) {
+ cp = strchr (buf, '\n');
+ if (cp != NULL) {
+ break;
+ }
+ }
+
+ fprintf (stderr,
+ _("%s: line %d: line too long\n"),
+ Prog, line);
+ errors++;
+ continue;
+ }
+ }
+
+ /*
+ * The username is the first field. It is separated from the
+ * password with a ":" character which is replaced with a
+ * NUL to give the new password. The new password will then
+ * be encrypted in the normal fashion with a new salt
+ * generated, unless the '-e' is given, in which case it is
+ * assumed to already be encrypted.
+ */
+
+ name = buf;
+ cp = strchr (name, ':');
+ if (NULL != cp) {
+ *cp = '\0';
+ cp++;
+ } else {
+ fprintf (stderr,
+ _("%s: line %d: missing new password\n"),
+ Prog, line);
+ errors++;
+ continue;
+ }
+ newpwd = cp;
+
+#ifdef USE_PAM
+ if (use_pam) {
+ if (do_pam_passwd_non_interactive ("chpasswd", name, newpwd) != 0) {
+ fprintf (stderr,
+ _("%s: (line %d, user %s) password not changed\n"),
+ Prog, line, name);
+ errors++;
+ }
+ } else
+#endif /* USE_PAM */
+ {
+ const struct spwd *sp;
+ struct spwd newsp;
+ const struct passwd *pw;
+ struct passwd newpw;
+
+ if (salt) {
+ cp = pw_encrypt (newpwd, salt);
+ if (NULL == cp) {
+ fprintf (stderr,
+ _("%s: failed to crypt password with salt '%s': %s\n"),
+ Prog, salt, strerror (errno));
+ fail_exit (1);
+ }
+ }
+
+ /*
+ * Get the password file entry for this user. The user must
+ * already exist.
+ */
+ pw = pw_locate (name);
+ if (NULL == pw) {
+ fprintf (stderr,
+ _("%s: line %d: user '%s' does not exist\n"), Prog,
+ line, name);
+ errors++;
+ continue;
+ }
+ if (is_shadow_pwd) {
+ /* The shadow entry should be updated if the
+ * passwd entry has a password set to 'x'.
+ * But on the other hand, if there is already both
+ * a passwd and a shadow password, it's preferable
+ * to update both.
+ */
+ sp = spw_locate (name);
+
+ if ( (NULL == sp)
+ && (strcmp (pw->pw_passwd,
+ SHADOW_PASSWD_STRING) == 0)) {
+ /* If the password is set to 'x' in
+ * passwd, but there are no entries in
+ * shadow, create one.
+ */
+ newsp.sp_namp = name;
+ /* newsp.sp_pwdp = NULL; will be set later */
+ /* newsp.sp_lstchg= 0; will be set later */
+ newsp.sp_min = getdef_num ("PASS_MIN_DAYS", -1);
+ newsp.sp_max = getdef_num ("PASS_MAX_DAYS", -1);
+ newsp.sp_warn = getdef_num ("PASS_WARN_AGE", -1);
+ newsp.sp_inact = -1;
+ newsp.sp_expire= -1;
+ newsp.sp_flag = SHADOW_SP_FLAG_UNSET;
+ sp = &newsp;
+ }
+ } else {
+ sp = NULL;
+ }
+
+ /*
+ * The freshly encrypted new password is merged into the
+ * user's password file entry and the last password change
+ * date is set to the current date.
+ */
+ if (NULL != sp) {
+ newsp = *sp;
+ newsp.sp_pwdp = cp;
+ newsp.sp_lstchg = (long) gettime () / SCALE;
+ if (0 == newsp.sp_lstchg) {
+ /* Better disable aging than requiring a
+ * password change */
+ newsp.sp_lstchg = -1;
+ }
+ }
+
+ if ( (NULL == sp)
+ || (strcmp (pw->pw_passwd, SHADOW_PASSWD_STRING) != 0)) {
+ newpw = *pw;
+ newpw.pw_passwd = cp;
+ }
+
+ /*
+ * The updated password file entry is then put back and will
+ * be written to the password file later, after all the
+ * other entries have been updated as well.
+ */
+ if (NULL != sp) {
+ if (spw_update (&newsp) == 0) {
+ fprintf (stderr,
+ _("%s: line %d: failed to prepare the new %s entry '%s'\n"),
+ Prog, line, spw_dbname (), newsp.sp_namp);
+ errors++;
+ continue;
+ }
+ }
+ if ( (NULL == sp)
+ || (strcmp (pw->pw_passwd, SHADOW_PASSWD_STRING) != 0)) {
+ if (pw_update (&newpw) == 0) {
+ fprintf (stderr,
+ _("%s: line %d: failed to prepare the new %s entry '%s'\n"),
+ Prog, line, pw_dbname (), newpw.pw_name);
+ errors++;
+ continue;
+ }
+ }
+ }
+ }
+
+ /*
+ * Any detected errors will cause the entire set of changes to be
+ * aborted. Unlocking the password file will cause all of the
+ * changes to be ignored. Otherwise the file is closed, causing the
+ * changes to be written out all at once, and then unlocked
+ * afterwards.
+ *
+ * With PAM, it is not possible to delay the update of the
+ * password database.
+ */
+ if (0 != errors) {
+#ifdef USE_PAM
+ if (!use_pam)
+#endif /* USE_PAM */
+ {
+ fprintf (stderr,
+ _("%s: error detected, changes ignored\n"),
+ Prog);
+ }
+ fail_exit (1);
+ }
+
+#ifdef USE_PAM
+ if (!use_pam)
+#endif /* USE_PAM */
+ {
+ /* Save the changes */
+ close_files ();
+ }
+
+ nscd_flush_cache ("passwd");
+ sssd_flush_cache (SSSD_DB_PASSWD);
+
+ return (0);
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 06:05:41 +0000