Exemple #1
0
void chown_tty (const struct passwd *info)
{
	struct group *grent;
	gid_t gid;

	/*
	 * See if login.defs has some value configured for the port group
	 * ID.  Otherwise, use the user's primary group ID.
	 */

	grent = getgr_nam_gid (getdef_str ("TTYGROUP"));
	if (NULL != grent) {
		gid = grent->gr_gid;
	} else {
		gid = info->pw_gid;
	}

	/*
	 * Change the permissions on the TTY to be owned by the user with
	 * the group as determined above.
	 */

	if (   (fchown (STDIN_FILENO, info->pw_uid, gid) != 0)
	    || (fchmod (STDIN_FILENO, getdef_num ("TTYPERM", 0600)) != 0)) {
		int err = errno;

		fprintf (stderr,
		         _("Unable to change owner or mode of tty stdin: %s"),
		         strerror (err));
		SYSLOG ((LOG_WARN,
		         "unable to change owner or mode of tty stdin for user `%s': %s\n",
		         info->pw_name, strerror (err)));
		if (EROFS != err) {
			closelog ();
			exit (EXIT_FAILURE);
		}
	}
#ifdef __linux__
	/*
	 * Please don't add code to chown /dev/vcs* to the user logging in -
	 * it's a potential security hole.  I wouldn't like the previous user
	 * to hold the file descriptor open and watch my screen.  We don't
	 * have the *BSD revoke() system call yet, and vhangup() only works
	 * for tty devices (which vcs* is not).  --marekm
	 */
#endif
}
Exemple #2
0
static int get_groups (char *list)
{
	char *cp;
	const struct group *grp;
	int errors = 0;
	int ngroups = 0;

	/*
	 * Initialize the list to be empty
	 */

	user_groups[0] = (char *) 0;

	if (!*list)
		return 0;

	/*
	 * So long as there is some data to be converted, strip off each
	 * name and look it up. A mix of numerical and string values for
	 * group identifiers is permitted.
	 */

	do {
		/*
		 * Strip off a single name from the list
		 */
		if ((cp = strchr (list, ',')))
			*cp++ = '\0';

		/*
		 * Names starting with digits are treated as numerical GID
		 * values, otherwise the string is looked up as is.
		 */
		grp = getgr_nam_gid (list);

		/*
		 * There must be a match, either by GID value or by
		 * string name.
		 */
		if (!grp) {
			fprintf (stderr, _("%s: unknown group %s\n"),
				 Prog, list);
			errors++;
		}
		list = cp;

		/*
		 * If the group doesn't exist, don't dump core. Instead,
		 * try the next one.  --marekm
		 */
		if (!grp)
			continue;

#ifdef	USE_NIS
		/*
		 * Don't add this group if they are an NIS group. Tell the
		 * user to go to the server for this group.
		 */

		if (__isgrNIS ()) {
			fprintf (stderr,
				 _("%s: group `%s' is a NIS group.\n"),
				 Prog, grp->gr_name);
			continue;
		}
#endif

		if (ngroups == sys_ngroups) {
			fprintf (stderr,
				 _
				 ("%s: too many groups specified (max %d).\n"),
				 Prog, ngroups);
			break;
		}

		/*
		 * Add the group name to the user's list of groups.
		 */

		user_groups[ngroups++] = xstrdup (grp->gr_name);
	} while (list);

	user_groups[ngroups] = (char *) 0;

	/*
	 * Any errors in finding group names are fatal
	 */

	if (errors)
		return -1;

	return 0;
}
Exemple #3
0
/*
 * process_flags - perform command line argument setting
 *
 *	process_flags() interprets the command line arguments and sets the
 *	values that the user will be created with accordingly. The values
 *	are checked for sanity.
 */
static void process_flags (int argc, char **argv)
{
	const struct group *grp;
	const struct passwd *pwd;

	const struct spwd *spwd = NULL;
	int anyflag = 0;
	int arg;

	if (argc == 1 || argv[argc - 1][0] == '-')
		usage ();

	if (!(pwd = getpwnam (argv[argc - 1]))) {
		fprintf (stderr, _("%s: user %s does not exist\n"),
			 Prog, argv[argc - 1]);
		exit (E_NOTFOUND);
	}

	user_name = argv[argc - 1];
	user_id = pwd->pw_uid;
	user_gid = pwd->pw_gid;
	user_comment = xstrdup (pwd->pw_gecos);
	user_home = xstrdup (pwd->pw_dir);
	user_shell = xstrdup (pwd->pw_shell);
#ifdef WITH_AUDIT
	user_newname = user_name;
	user_newid = user_id;
	user_newgid = user_gid;
	user_newcomment = user_comment;
	user_newhome = user_home;
	user_newshell = user_shell;
#endif

#ifdef	USE_NIS
	/*
	 * Now make sure it isn't an NIS user.
	 */
	if (__ispwNIS ()) {
		char *nis_domain;
		char *nis_master;

		fprintf (stderr, _("%s: user %s is a NIS user\n"),
			 Prog, user_name);

		if (!yp_get_default_domain (&nis_domain) &&
		    !yp_master (nis_domain, "passwd.byname", &nis_master)) {
			fprintf (stderr, _("%s: %s is the NIS master\n"),
				 Prog, nis_master);
		}
		exit (E_NOTFOUND);
	}
#endif

	if (is_shadow_pwd && (spwd = getspnam (user_name))) {
		user_expire = spwd->sp_expire;
		user_inactive = spwd->sp_inact;
#ifdef WITH_AUDIT
		user_newexpire = user_expire;
		user_newinactive = user_inactive;
#endif
	}

	{
		/*
		 * Parse the command line options.
		 */
		int c;
		static struct option long_options[] = {
			{"append", required_argument, NULL, 'a'},
			{"comment", required_argument, NULL, 'c'},
			{"home", required_argument, NULL, 'd'},
			{"expiredate", required_argument, NULL, 'e'},
			{"inactive", required_argument, NULL, 'f'},
			{"gid", required_argument, NULL, 'g'},
			{"groups", required_argument, NULL, 'G'},
			{"help", no_argument, NULL, 'h'},
			{"login", required_argument, NULL, 'l'},
			{"lock", no_argument, NULL, 'L'},
			{"move-home", no_argument, NULL, 'm'},
			{"non-unique", no_argument, NULL, 'o'},
			{"password", required_argument, NULL, 'p'},
			{"shell", required_argument, NULL, 's'},
			{"uid", required_argument, NULL, 'u'},
			{"unlock", no_argument, NULL, 'U'},
			{NULL, 0, NULL, '\0'}
		};
		while ((c =
			getopt_long (argc, argv, "ac:d:e:f:g:G:l:Lmop:s:u:U",
				     long_options, NULL)) != -1) {
			switch (c) {
			case 'a':
				aflg++;
				break;
			case 'c':
				if (!VALID (optarg)) {
					fprintf (stderr,
						 _("%s: invalid field `%s'\n"),
						 Prog, optarg);
					exit (E_BAD_ARG);
				}
#ifdef WITH_AUDIT
				user_newcomment = optarg;
#else
				user_comment = optarg;
#endif
				cflg++;
				break;
			case 'd':
				if (!VALID (optarg)) {
					fprintf (stderr,
						 _("%s: invalid field `%s'\n"),
						 Prog, optarg);
					exit (E_BAD_ARG);
				}
				dflg++;
				user_newhome = optarg;
				break;
			case 'e':
				if (*optarg) {
#ifdef WITH_AUDIT
					user_newexpire = strtoday (optarg);
					if (user_newexpire == -1) {
#else
					user_expire = strtoday (optarg);
					if (user_expire == -1) {
#endif
						fprintf (stderr,
							 _
							 ("%s: invalid date `%s'\n"),
							 Prog, optarg);
						exit (E_BAD_ARG);
					}
#ifdef WITH_AUDIT
					user_newexpire *= DAY / SCALE;
#else
					user_expire *= DAY / SCALE;
#endif
				} else
#ifdef WITH_AUDIT
					user_newexpire = -1;
#else
					user_expire = -1;
#endif
				eflg++;
				break;
			case 'f':
#ifdef WITH_AUDIT
				user_newinactive = get_number (optarg);
#else
				user_inactive = get_number (optarg);
#endif
				fflg++;
				break;
			case 'g':
				grp = getgr_nam_gid (optarg);
				if (!grp) {
					fprintf (stderr,
						 _("%s: unknown group %s\n"),
						 Prog, optarg);
					exit (E_NOTFOUND);
				}
				user_newgid = grp->gr_gid;
				gflg++;
				break;
			case 'G':
				if (get_groups (optarg))
					exit (E_NOTFOUND);
				Gflg++;
				break;
			case 'l':
				if (!check_user_name (optarg)) {
					fprintf (stderr,
						 _("%s: invalid field `%s'\n"),
						 Prog, optarg);
					exit (E_BAD_ARG);
				}

				/*
				 * If the name does not really change, we mustn't
				 * set the flag as this will cause rather serious
				 * problems later!
				 */
				if (strcmp (user_name, optarg))
					lflg++;

				user_newname = optarg;
				break;
			case 'L':
				if (Uflg || pflg)
					usage ();

				Lflg++;
				break;
			case 'm':
				if (!dflg)
					usage ();

				mflg++;
				break;
			case 'o':
				if (!uflg)
					usage ();

				oflg++;
				break;
			case 'p':
				if (Lflg || Uflg)
					usage ();

				user_pass = optarg;
				pflg++;
				break;
			case 's':
				if (!VALID (optarg)) {
					fprintf (stderr,
						 _("%s: invalid field `%s'\n"),
						 Prog, optarg);
					exit (E_BAD_ARG);
				}
#ifdef WITH_AUDIT
				user_newshell = optarg;
#else
				user_shell = optarg;
#endif
				sflg++;
				break;
			case 'u':
				user_newid = get_id (optarg);
				uflg++;
				break;
			case 'U':
				if (Lflg && pflg)
					usage ();

				Uflg++;
				break;
			default:
				usage ();
			}
			anyflag++;
		}
	}

	if (anyflag == 0) {
		fprintf (stderr, _("%s: no flags given\n"), Prog);
		exit (E_USAGE);
	}
	if (!is_shadow_pwd && (eflg || fflg)) {
		fprintf (stderr,
			 _
			 ("%s: shadow passwords required for -e and -f\n"),
			 Prog);
		exit (E_USAGE);
	}

	if (optind != argc - 1)
		usage ();

	if (aflg && (!Gflg)) {
		fprintf (stderr,
			 _("%s: -a flag is ONLY allowed with the -G flag\n"),
			 Prog);
		usage ();
		exit (E_USAGE);
	}

	if (dflg && strcmp (user_home, user_newhome) == 0)
		dflg = mflg = 0;

	if (uflg && user_id == user_newid)
		uflg = oflg = 0;

	if (lflg && getpwnam (user_newname)) {
		fprintf (stderr, _("%s: user %s exists\n"), Prog, user_newname);
		exit (E_NAME_IN_USE);
	}

	if (uflg && !oflg && getpwuid (user_newid)) {
		fprintf (stderr, _("%s: uid %lu is not unique\n"),
			 Prog, (unsigned long) user_newid);
		exit (E_UID_IN_USE);
	}
}

/*
 * close_files - close all of the files that were opened
 *
 *	close_files() closes all of the files that were opened for this new
 *	user. This causes any modified entries to be written out.
 */
static void close_files (void)
{
	if (!pw_close ()) {
		fprintf (stderr, _("%s: cannot rewrite password file\n"), Prog);
		fail_exit (E_PW_UPDATE);
	}
	if (is_shadow_pwd && !spw_close ()) {
		fprintf (stderr,
			 _("%s: cannot rewrite shadow password file\n"), Prog);
		fail_exit (E_PW_UPDATE);
	}
	if (is_shadow_pwd)
		spw_unlock ();
	(void) pw_unlock ();

	/*
	 * Close the DBM and/or flat files
	 */
	endpwent ();
	endspent ();
	endgrent ();
#ifdef	SHADOWGRP
	endsgent ();
#endif
}

/*
 * open_files - lock and open the password files
 *
 *	open_files() opens the two password files.
 */
static void open_files (void)
{
	if (!pw_lock ()) {
		fprintf (stderr, _("%s: unable to lock password file\n"), Prog);
		exit (E_PW_UPDATE);
	}
	if (!pw_open (O_RDWR)) {
		fprintf (stderr, _("%s: unable to open password file\n"), Prog);
		fail_exit (E_PW_UPDATE);
	}
	if (is_shadow_pwd && !spw_lock ()) {
		fprintf (stderr,
			 _("%s: cannot lock shadow password file\n"), Prog);
		fail_exit (E_PW_UPDATE);
	}
	if (is_shadow_pwd && !spw_open (O_RDWR)) {
		fprintf (stderr,
			 _("%s: cannot open shadow password file\n"), Prog);
		fail_exit (E_PW_UPDATE);
	}
}

/*
 * usr_update - create the user entries
 *
 *	usr_update() creates the password file entries for this user and
 *	will update the group entries if required.
 */
static void usr_update (void)
{
	struct passwd pwent;
	const struct passwd *pwd;

	struct spwd spent;
	const struct spwd *spwd = NULL;

	/*
	 * Locate the entry in /etc/passwd, which MUST exist.
	 */
	pwd = pw_locate (user_name);
	if (!pwd) {
		fprintf (stderr, _("%s: %s not found in /etc/passwd\n"),
			 Prog, user_name);
		fail_exit (E_NOTFOUND);
	}
	pwent = *pwd;
	new_pwent (&pwent);


	/* 
	 * Locate the entry in /etc/shadow. It doesn't have to exist, and
	 * won't be created if it doesn't.
	 */
	if (is_shadow_pwd && (spwd = spw_locate (user_name))) {
		spent = *spwd;
		new_spent (&spent);
	}

	if (lflg || uflg || gflg || cflg || dflg || sflg || pflg
	    || Lflg || Uflg) {
		if (!pw_update (&pwent)) {
			fprintf (stderr,
				 _("%s: error changing password entry\n"),
				 Prog);
			fail_exit (E_PW_UPDATE);
		}
		if (lflg && !pw_remove (user_name)) {
			fprintf (stderr,
				 _("%s: error removing password entry\n"),
				 Prog);
			fail_exit (E_PW_UPDATE);
		}
	}
	if (spwd && (lflg || eflg || fflg || pflg || Lflg || Uflg)) {
		if (!spw_update (&spent)) {
			fprintf (stderr,
				 _
				 ("%s: error adding new shadow password entry\n"),
				 Prog);
			fail_exit (E_PW_UPDATE);
		}
		if (lflg && !spw_remove (user_name)) {
			fprintf (stderr,
				 _
				 ("%s: error removing shadow password entry\n"),
				 Prog);
			fail_exit (E_PW_UPDATE);
		}
	}
}

/*
 * move_home - move the user's home directory
 *
 *	move_home() moves the user's home directory to a new location. The
 *	files will be copied if the directory cannot simply be renamed.
 */
static void move_home (void)
{
	struct stat sb;

	if (mflg && stat (user_home, &sb) == 0) {
		/*
		 * Don't try to move it if it is not a directory
		 * (but /dev/null for example).  --marekm
		 */
		if (!S_ISDIR (sb.st_mode))
			return;

		if (access (user_newhome, F_OK) == 0) {
			fprintf (stderr, _("%s: directory %s exists\n"),
				 Prog, user_newhome);
			fail_exit (E_HOMEDIR);
		} else if (rename (user_home, user_newhome)) {
			if (errno == EXDEV) {
				if (mkdir (user_newhome, sb.st_mode & 0777)) {
					fprintf (stderr,
						 _
						 ("%s: can't create %s\n"),
						 Prog, user_newhome);
				}
				if (chown (user_newhome, sb.st_uid, sb.st_gid)) {
					fprintf (stderr,
						 _("%s: can't chown %s\n"),
						 Prog, user_newhome);
					rmdir (user_newhome);
					fail_exit (E_HOMEDIR);
				}
				if (copy_tree (user_home, user_newhome,
					       uflg ? user_newid : -1,
					       gflg ? user_newgid : -1) == 0) {
					if (remove_tree (user_home) != 0 ||
					    rmdir (user_home) != 0)
						fprintf (stderr,
							 _
							 ("%s: warning: failed to completely remove old home directory %s"),
							 Prog, user_home);
#ifdef WITH_AUDIT
					audit_logger (AUDIT_USER_CHAUTHTOK,
						      Prog,
						      "moving home directory",
						      user_newname, user_newid,
						      1);
#endif
					return;
				}

				(void) remove_tree (user_newhome);
				(void) rmdir (user_newhome);
			}
			fprintf (stderr,
				 _
				 ("%s: cannot rename directory %s to %s\n"),
				 Prog, user_home, user_newhome);
			fail_exit (E_HOMEDIR);
		}
#ifdef WITH_AUDIT
		audit_logger (AUDIT_USER_CHAUTHTOK, Prog,
			      "moving home directory", user_newname, user_newid,
			      1);
#endif
	}
	if (uflg || gflg) {
#ifdef WITH_AUDIT
		audit_logger (AUDIT_USER_CHAUTHTOK, Prog,
			      "changing home directory owner", user_newname,
			      user_newid, 1);
#endif
		chown (dflg ? user_newhome : user_home,
		       uflg ? user_newid : user_id,
		       gflg ? user_newgid : user_gid);
	}
}

/*
 * update_files - update the lastlog and faillog files
 */
static void update_files (void)
{
	struct lastlog ll;
	struct faillog fl;
	int fd;

	/*
	 * Relocate the "lastlog" entries for the user. The old entry is
	 * left alone in case the UID was shared. It doesn't hurt anything
	 * to just leave it be.
	 */
	if ((fd = open (LASTLOG_FILE, O_RDWR)) != -1) {
		lseek (fd, (off_t) user_id * sizeof ll, SEEK_SET);
		if (read (fd, (char *) &ll, sizeof ll) == sizeof ll) {
			lseek (fd, (off_t) user_newid * sizeof ll, SEEK_SET);
			write (fd, (char *) &ll, sizeof ll);
		}
		close (fd);
	}

	/*
	 * Relocate the "faillog" entries in the same manner.
	 */
	if ((fd = open (FAILLOG_FILE, O_RDWR)) != -1) {
		lseek (fd, (off_t) user_id * sizeof fl, SEEK_SET);
		if (read (fd, (char *) &fl, sizeof fl) == sizeof fl) {
			lseek (fd, (off_t) user_newid * sizeof fl, SEEK_SET);
			write (fd, (char *) &fl, sizeof fl);
		}
		close (fd);
	}
}

#ifndef NO_MOVE_MAILBOX
/*
 * This is the new and improved code to carefully chown/rename the user's
 * mailbox. Maybe I am too paranoid but the mail spool dir sometimes
 * happens to be mode 1777 (this makes mail user agents work without
 * being setgid mail, but is NOT recommended; they all should be fixed
 * to use movemail).  --marekm
 */
static void move_mailbox (void)
{
	const char *maildir;
	char mailfile[1024], newmailfile[1024];
	int fd;
	struct stat st;

	maildir = getdef_str ("MAIL_DIR");
#ifdef MAIL_SPOOL_DIR
	if (!maildir && !getdef_str ("MAIL_FILE"))
		maildir = MAIL_SPOOL_DIR;
#endif
	if (!maildir)
		return;

	/*
	 * O_NONBLOCK is to make sure open won't hang on mandatory locks.
	 * We do fstat/fchown to make sure there are no races (someone
	 * replacing /var/spool/mail/luser with a hard link to /etc/passwd
	 * between stat and chown).  --marekm
	 */
	snprintf (mailfile, sizeof mailfile, "%s/%s", maildir, user_name);
	fd = open (mailfile, O_RDONLY | O_NONBLOCK, 0);
	if (fd < 0) {
		/* no need for warnings if the mailbox doesn't exist */
		if (errno != ENOENT)
			perror (mailfile);
		return;
	}
	if (fstat (fd, &st) < 0) {
		perror ("fstat");
		close (fd);
		return;
	}
	if (st.st_uid != user_id) {
		/* better leave it alone */
		fprintf (stderr, _("%s: warning: %s not owned by %s\n"),
			 Prog, mailfile, user_name);
		close (fd);
		return;
	}
	if (uflg) {
		if (fchown (fd, user_newid, (gid_t) - 1) < 0) {
			perror (_("failed to change mailbox owner"));
		}
#ifdef WITH_AUDIT
		else {
			audit_logger (AUDIT_USER_CHAUTHTOK, Prog,
				      "changing mail file owner", user_newname,
				      user_newid, 1);
		}
#endif
	}

	close (fd);

	if (lflg) {
		snprintf (newmailfile, sizeof newmailfile, "%s/%s",
			  maildir, user_newname);
		if (link (mailfile, newmailfile) || unlink (mailfile)) {
			perror (_("failed to rename mailbox"));
		}
#ifdef WITH_AUDIT
		else {
			audit_logger (AUDIT_USER_CHAUTHTOK, Prog,
				      "changing mail file name", user_newname,
				      user_newid, 1);
		}
#endif
	}
}
#endif

/*
 * main - usermod command
 */
int main (int argc, char **argv)
{
	int grp_err = 0;

#ifdef USE_PAM
	pam_handle_t *pamh = NULL;
	struct passwd *pampw;
	int retval;
#endif

#ifdef WITH_AUDIT
	audit_help_open ();
#endif

	/*
	 * Get my name so that I can use it to report errors.
	 */
	Prog = Basename (argv[0]);

	setlocale (LC_ALL, "");
	bindtextdomain (PACKAGE, LOCALEDIR);
	textdomain (PACKAGE);

	sys_ngroups = sysconf (_SC_NGROUPS_MAX);
	user_groups = malloc ((1 + sys_ngroups) * sizeof (char *));
	user_groups[0] = (char *) 0;

	OPENLOG ("usermod");

	is_shadow_pwd = spw_file_present ();
#ifdef SHADOWGRP
	is_shadow_grp = sgr_file_present ();
#endif

	process_flags (argc, argv);

#ifdef USE_PAM
	retval = PAM_SUCCESS;

	pampw = getpwuid (getuid ());
	if (pampw == NULL) {
		retval = PAM_USER_UNKNOWN;
	}

	if (retval == PAM_SUCCESS) {
		retval = pam_start ("usermod", pampw->pw_name, &conv, &pamh);
	}

	if (retval == PAM_SUCCESS) {
		retval = pam_authenticate (pamh, 0);
		if (retval != PAM_SUCCESS) {
			pam_end (pamh, retval);
		}
	}

	if (retval == PAM_SUCCESS) {
		retval = pam_acct_mgmt (pamh, 0);
		if (retval != PAM_SUCCESS) {
			pam_end (pamh, retval);
		}
	}

	if (retval != PAM_SUCCESS) {
		fprintf (stderr, _("%s: PAM authentication failed\n"), Prog);
		exit (1);
	}
#endif				/* USE_PAM */

	/*
	 * Do the hard stuff - open the files, change the user entries,
	 * change the home directory, then close and update the files.
	 */
	open_files ();

	usr_update ();
	nscd_flush_cache ("passwd");
	nscd_flush_cache ("group");

	close_files ();

	if (Gflg || lflg)
		grp_err = grp_update ();

	if (mflg)
		move_home ();

#ifndef NO_MOVE_MAILBOX
	if (lflg || uflg)
		move_mailbox ();
#endif

	if (uflg) {
		update_files ();

		/*
		 * Change the UID on all of the files owned by `user_id' to
		 * `user_newid' in the user's home directory.
		 */
		chown_tree (dflg ? user_newhome : user_home,
			    user_id, user_newid,
			    user_gid, gflg ? user_newgid : user_gid);
	}

	if (grp_err)
		exit (E_GRP_UPDATE);

#ifdef USE_PAM
	if (retval == PAM_SUCCESS)
		pam_end (pamh, PAM_SUCCESS);
#endif				/* USE_PAM */

	exit (E_SUCCESS);
	/* NOT REACHED */
}