usr.bin/passwd/passwd.c

   1 /*-
   2  * Copyright (c) 2002 Networks Associates Technologies, Inc.
   3  * All rights reserved.
   4  *
   5  * This software was developed for the FreeBSD Project by ThinkSec AS and
   6  * NAI Labs, the Security Research Division of Network Associates, Inc.
   7  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
   8  * DARPA CHATS research program.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. The name of the author may not be used to endorse or promote
  19  *    products derived from this software without specific prior written
  20  *    permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $FreeBSD: src/usr.bin/passwd/passwd.c,v 1.23 2003/04/18 21:27:09 nectar Exp $
  35  */
  36
  37 #include <sys/param.h>
  38
  39 #include <err.h>
  40 #include <pwd.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <syslog.h>
  44 #include <unistd.h>
  45
  46 #include <security/pam_appl.h>
  47 #include <security/openpam.h>
  48
  49 static pam_handle_t *pamh;
  50 static struct pam_conv pamc = {
  51         openpam_ttyconv,
  52         NULL
  53 };
  54
  55 static char     *yp_domain;
  56 static char     *yp_host;
  57
  58 static void
  59 usage(void)
  60 {
  61         fprintf(stderr, "usage: passwd [-ly] [-d domain] [-h host] [user]\n");
  62         exit(1);
  63 }
  64
  65 int
  66 main(int argc, char **argv)
  67 {
  68         char hostname[MAXHOSTNAMELEN];
  69         struct passwd *pwd = NULL;
  70         int o, pam_err;
  71         uid_t uid;
  72
  73         while ((o = getopt(argc, argv, "d:h:loy")) != -1)
  74                 switch (o) {
  75                 case 'd':
  76                         yp_domain = optarg;
  77                         break;
  78                 case 'h':
  79                         yp_host = optarg;
  80                         break;
  81                 case 'l':
  82                 case 'o':
  83                 case 'y':
  84                         /* compatibility */
  85                         break;
  86                 default:
  87                         usage();
  88                 }
  89
  90         argc -= optind;
  91         argv += optind;
  92
  93         uid = getuid();
  94
  95         switch (argc) {
  96         case 0:
  97                 if ((pwd = getpwuid(uid)) == NULL)
  98                         errx(1, "who are you?");
  99                 break;
 100         case 1:
 101                 if ((pwd = getpwnam(*argv)) == NULL)
 102                         errx(1, "%s: no such user", *argv);
 103                 break;
 104         default:
 105                 usage();
 106         }
 107
 108         if (uid != 0 && uid != pwd->pw_uid)
 109                 errx(1, "permission denied");
 110
 111         /* check where the user's from */
 112         switch (pwd->pw_fields & _PWF_SOURCE) {
 113         case _PWF_FILES:
 114                 fprintf(stderr, "Changing local password for %s\n",
 115                     pwd->pw_name);
 116                 break;
 117         case _PWF_NIS:
 118                 fprintf(stderr, "Changing NIS password for %s\n",
 119                     pwd->pw_name);
 120                 break;
 121         default:
 122                 fprintf(stderr, "Changing password for %s\n",
 123                     pwd->pw_name);
 124         }
 125
 126 #define pam_check(func) do { \
 127         if (pam_err != PAM_SUCCESS) { \
 128                 if (pam_err == PAM_AUTH_ERR || pam_err == PAM_PERM_DENIED || \
 129                     pam_err == PAM_AUTHTOK_RECOVERY_ERR) \
 130                         warnx("sorry"); \
 131                 else \
 132                         warnx("%s(): %s", func, pam_strerror(pamh, pam_err)); \
 133                 goto end; \
 134         } \
 135 } while (0)
 136
 137         /* initialize PAM */
 138         pam_err = pam_start("passwd", pwd->pw_name, &pamc, &pamh);
 139         pam_check("pam_start");
 140
 141         pam_err = pam_set_item(pamh, PAM_TTY, ttyname(STDERR_FILENO));
 142         pam_check("pam_set_item");
 143         gethostname(hostname, sizeof hostname);
 144         pam_err = pam_set_item(pamh, PAM_RHOST, hostname);
 145         pam_check("pam_set_item");
 146         pam_err = pam_set_item(pamh, PAM_RUSER, getlogin());
 147         pam_check("pam_set_item");
 148
 149         /* set YP domain and host */
 150         pam_err = pam_set_data(pamh, "yp_domain", yp_domain, NULL);
 151         pam_check("pam_set_data");
 152         pam_err = pam_set_data(pamh, "yp_server", yp_host, NULL);
 153         pam_check("pam_set_data");
 154
 155         /* set new password */
 156         pam_err = pam_chauthtok(pamh, 0);
 157         pam_check("pam_chauthtok");
 158
 159  end:
 160         pam_end(pamh, pam_err);
 161         exit(pam_err == PAM_SUCCESS ? 0 : 1);
 162 }