2 * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
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.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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
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
34 * $P4: //depot/projects/openpam/lib/openpam_borrow_cred.c#13 $
37 #include <sys/param.h>
45 #include <security/pam_appl.h>
47 #include "openpam_impl.h"
52 * Temporarily borrow user credentials
56 openpam_borrow_cred(pam_handle_t *pamh,
57 const struct passwd *pwd)
59 struct pam_saved_cred *scred;
64 r = pam_get_data(pamh, PAM_SAVED_CRED, &scredp);
65 if (r == PAM_SUCCESS && scredp != NULL) {
66 openpam_log(PAM_LOG_DEBUG,
67 "already operating under borrowed credentials");
68 RETURNC(PAM_SYSTEM_ERR);
70 if (geteuid() != 0 && geteuid() != pwd->pw_uid) {
71 openpam_log(PAM_LOG_DEBUG, "called with non-zero euid: %d",
73 RETURNC(PAM_PERM_DENIED);
75 scred = calloc(1, sizeof *scred);
78 scred->euid = geteuid();
79 scred->egid = getegid();
80 r = getgroups(NGROUPS_MAX, scred->groups);
83 RETURNC(PAM_SYSTEM_ERR);
86 r = pam_set_data(pamh, PAM_SAVED_CRED, scred, &openpam_free_data);
87 if (r != PAM_SUCCESS) {
91 if (geteuid() == pwd->pw_uid)
93 if (initgroups(pwd->pw_name, pwd->pw_gid) < 0 ||
94 setegid(pwd->pw_gid) < 0 || seteuid(pwd->pw_uid) < 0) {
95 openpam_restore_cred(pamh);
96 RETURNC(PAM_SYSTEM_ERR);
111 * The =openpam_borrow_cred function saves the current credentials and
112 * switches to those of the user specified by its =pwd argument.
113 * The affected credentials are the effective UID, the effective GID, and
114 * the group access list.
115 * The original credentials can be restored using =openpam_restore_cred.