contrib/openpam/lib/openpam_restore_cred.c

   1 /*-
   2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
   3  * All rights reserved.
   4  *
   5  * This software was developed for the FreeBSD Project by ThinkSec AS and
   6  * Network Associates Laboratories, the Security Research Division of
   7  * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
   8  * ("CBOSS"), as part of the 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  * $P4: //depot/projects/openpam/lib/openpam_restore_cred.c#11 $
  35  */
  36
  37 #include <sys/param.h>
  38
  39 #include <grp.h>
  40 #include <limits.h>
  41 #include <pwd.h>
  42 #include <stdlib.h>
  43 #include <unistd.h>
  44
  45 #include <security/pam_appl.h>
  46
  47 #include "openpam_impl.h"
  48
  49 /*
  50  * OpenPAM extension
  51  *
  52  * Restore credentials
  53  */
  54
  55 int
  56 openpam_restore_cred(pam_handle_t *pamh)
  57 {
  58         struct pam_saved_cred *scred;
  59         void *scredp;
  60         int r;
  61
  62         ENTER();
  63         r = pam_get_data(pamh, PAM_SAVED_CRED, &scredp);
  64         if (r != PAM_SUCCESS)
  65                 RETURNC(r);
  66         if (scredp == NULL)
  67                 RETURNC(PAM_SYSTEM_ERR);
  68         scred = scredp;
  69         if (scred->euid != geteuid()) {
  70                 if (seteuid(scred->euid) < 0 ||
  71                     setgroups(scred->ngroups, scred->groups) < 0 ||
  72                     setegid(scred->egid) < 0)
  73                         RETURNC(PAM_SYSTEM_ERR);
  74         }
  75         pam_set_data(pamh, PAM_SAVED_CRED, NULL, NULL);
  76         RETURNC(PAM_SUCCESS);
  77 }
  78
  79 /*
  80  * Error codes:
  81  *
  82  *      =pam_get_data
  83  *      PAM_SYSTEM_ERR
  84  */
  85
  86 /**
  87  * The =openpam_restore_cred function restores the credentials saved by
  88  * =openpam_borrow_cred.
  89  *
  90  * >setegid 2
  91  * >seteuid 2
  92  * >setgroups 2
  93  */