dist/openpam/modules/pam_unix/pam_unix.c

   1 /*-
   2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
   3  * Copyright (c) 2004-2007 Dag-Erling Smørgrav
   4  * All rights reserved.
   5  *
   6  * This software was developed for the FreeBSD Project by ThinkSec AS and
   7  * Network Associates Laboratories, the Security Research Division of
   8  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
   9  * ("CBOSS"), as part of the DARPA CHATS research program.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote
  20  *    products derived from this software without specific prior written
  21  *    permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * $Id: pam_unix.c,v 1.1.1.2 2008/01/27 00:54:49 christos Exp $
  36  */
  37
  38 #ifdef HAVE_CONFIG_H
  39 # include <config.h>
  40 #endif
  41
  42 #include <sys/param.h>
  43
  44 #include <pwd.h>
  45 #include <stdlib.h>
  46 #include <stdio.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49
  50 #ifdef HAVE_CRYPT_H
  51 # include <crypt.h>
  52 #endif
  53
  54 #include <security/pam_modules.h>
  55 #include <security/pam_appl.h>
  56
  57 #ifndef OPENPAM
  58 static char password_prompt[] = "Password:";
  59 #endif
  60
  61 #ifndef PAM_EXTERN
  62 #define PAM_EXTERN
  63 #endif
  64
  65 PAM_EXTERN int
  66 pam_sm_authenticate(pam_handle_t *pamh, int flags,
  67         int argc, const char *argv[])
  68 {
  69 #ifndef OPENPAM
  70         struct pam_conv *conv;
  71         struct pam_message msg;
  72         const struct pam_message *msgp;
  73         struct pam_response *resp;
  74 #endif
  75         struct passwd *pwd;
  76         const char *user;
  77         char *crypt_password, *password;
  78         int pam_err, retry;
  79
  80         (void)argc;
  81         (void)argv;
  82
  83         /* identify user */
  84         if ((pam_err = pam_get_user(pamh, &user, NULL)) != PAM_SUCCESS)
  85                 return (pam_err);
  86         if ((pwd = getpwnam(user)) == NULL)
  87                 return (PAM_USER_UNKNOWN);
  88
  89         /* get password */
  90 #ifndef OPENPAM
  91         pam_err = pam_get_item(pamh, PAM_CONV, (const void **)&conv);
  92         if (pam_err != PAM_SUCCESS)
  93                 return (PAM_SYSTEM_ERR);
  94         msg.msg_style = PAM_PROMPT_ECHO_OFF;
  95         msg.msg = password_prompt;
  96         msgp = &msg;
  97 #endif
  98         for (retry = 0; retry < 3; ++retry) {
  99 #ifdef OPENPAM
 100                 pam_err = pam_get_authtok(pamh, PAM_AUTHTOK,
 101                     (const char **)&password, NULL);
 102 #else
 103                 resp = NULL;
 104                 pam_err = (*conv->conv)(1, &msgp, &resp, conv->appdata_ptr);
 105                 if (resp != NULL) {
 106                         if (pam_err == PAM_SUCCESS)
 107                                 password = resp->resp;
 108                         else
 109                                 free(resp->resp);
 110                         free(resp);
 111                 }
 112 #endif
 113                 if (pam_err == PAM_SUCCESS)
 114                         break;
 115         }
 116         if (pam_err == PAM_CONV_ERR)
 117                 return (pam_err);
 118         if (pam_err != PAM_SUCCESS)
 119                 return (PAM_AUTH_ERR);
 120
 121         /* compare passwords */
 122         if ((!pwd->pw_passwd[0] && (flags & PAM_DISALLOW_NULL_AUTHTOK)) ||
 123             (crypt_password = crypt(password, pwd->pw_passwd)) == NULL ||
 124             strcmp(crypt_password, pwd->pw_passwd) != 0)
 125                 pam_err = PAM_AUTH_ERR;
 126         else
 127                 pam_err = PAM_SUCCESS;
 128 #ifndef OPENPAM
 129         free(password);
 130 #endif
 131         return (pam_err);
 132 }
 133
 134 PAM_EXTERN int
 135 pam_sm_setcred(pam_handle_t *pamh, int flags,
 136         int argc, const char *argv[])
 137 {
 138
 139         (void)pamh;
 140         (void)flags;
 141         (void)argc;
 142         (void)argv;
 143         return (PAM_SUCCESS);
 144 }
 145
 146 PAM_EXTERN int
 147 pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
 148         int argc, const char *argv[])
 149 {
 150
 151         (void)pamh;
 152         (void)flags;
 153         (void)argc;
 154         (void)argv;
 155         return (PAM_SUCCESS);
 156 }
 157
 158 PAM_EXTERN int
 159 pam_sm_open_session(pam_handle_t *pamh, int flags,
 160         int argc, const char *argv[])
 161 {
 162
 163         (void)pamh;
 164         (void)flags;
 165         (void)argc;
 166         (void)argv;
 167         return (PAM_SUCCESS);
 168 }
 169
 170 PAM_EXTERN int
 171 pam_sm_close_session(pam_handle_t *pamh, int flags,
 172         int argc, const char *argv[])
 173 {
 174
 175         (void)pamh;
 176         (void)flags;
 177         (void)argc;
 178         (void)argv;
 179         return (PAM_SUCCESS);
 180 }
 181
 182 PAM_EXTERN int
 183 pam_sm_chauthtok(pam_handle_t *pamh, int flags,
 184         int argc, const char *argv[])
 185 {
 186
 187         (void)pamh;
 188         (void)flags;
 189         (void)argc;
 190         (void)argv;
 191         return (PAM_SERVICE_ERR);
 192 }
 193
 194 #ifdef PAM_MODULE_ENTRY
 195 PAM_MODULE_ENTRY("pam_unix");
 196 #endif