pam_exec.c revision 110446 
1/*-
2 * Copyright (c) 2001 Networks Associates Technology, 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
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD: head/lib/libpam/modules/pam_exec/pam_exec.c 110446 2003-02-06 12:40:58Z des $");
37
38#include <sys/types.h>
39#include <sys/wait.h>
40
41#include <errno.h>
42#include <stdlib.h>
43#include <string.h>
44#include <unistd.h>
45
46#include <security/pam_appl.h>
47#include <security/pam_modules.h>
48#include <security/openpam.h>
49
50static int
51_pam_exec(pam_handle_t *pamh __unused, int flags __unused,
52    int argc, const char *argv[])
53{
54	int childerr, status;
55	char **env, **envlist;
56	pid_t pid;
57
58	if (argc < 1)
59		return (PAM_SERVICE_ERR);
60
61	/*
62	 * XXX For additional credit, divert child's stdin/stdout/stderr
63	 * to the conversation function.
64	 */
65	envlist = pam_getenvlist(pamh);
66	childerr = 0;
67	if ((pid = vfork()) == 0) {
68		execve(argv[0], argv, envlist);
69		childerr = errno;
70		_exit(1);
71	}
72	for (env = envlist; *env != NULL; ++env)
73		free(*env);
74	free(envlist);
75	if (pid == -1) {
76		openpam_log(PAM_LOG_ERROR, "vfork(): %m");
77		return (PAM_SYSTEM_ERR);
78	}
79	if (waitpid(pid, &status, 0) == -1) {
80		openpam_log(PAM_LOG_ERROR, "waitpid(): %m");
81		return (PAM_SYSTEM_ERR);
82	}
83	if (childerr != 0) {
84		openpam_log(PAM_LOG_ERROR, "execv(): %m");
85		return (PAM_SYSTEM_ERR);
86	}
87	if (WIFSIGNALED(status)) {
88		openpam_log(PAM_LOG_ERROR, "%s caught signal %d%s",
89		    argv[0], WTERMSIG(status),
90		    WCOREDUMP(status) ? " (core dumped)" : "");
91		return (PAM_SYSTEM_ERR);
92	}
93	if (!WIFEXITED(status)) {
94		openpam_log(PAM_LOG_ERROR, "unknown status 0x%x", status);
95		return (PAM_SYSTEM_ERR);
96	}
97	if (WEXITSTATUS(status) != 0) {
98		openpam_log(PAM_LOG_ERROR, "%s returned code %d",
99		    argv[0], WEXITSTATUS(status));
100		return (PAM_SYSTEM_ERR);
101	}
102	return (PAM_SUCCESS);
103}
104
105PAM_EXTERN int
106pam_sm_authenticate(pam_handle_t *pamh, int flags,
107    int argc, const char *argv[])
108{
109
110	return (_pam_exec(pamh, flags, argc, argv));
111}
112
113PAM_EXTERN int
114pam_sm_setcred(pam_handle_t *pamh, int flags,
115    int argc, const char *argv[])
116{
117
118	return (_pam_exec(pamh, flags, argc, argv));
119}
120
121PAM_EXTERN int
122pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
123    int argc, const char *argv[])
124{
125
126	return (_pam_exec(pamh, flags, argc, argv));
127}
128
129PAM_EXTERN int
130pam_sm_open_session(pam_handle_t *pamh, int flags,
131    int argc, const char *argv[])
132{
133
134	return (_pam_exec(pamh, flags, argc, argv));
135}
136
137PAM_EXTERN int
138pam_sm_close_session(pam_handle_t *pamh, int flags,
139    int argc, const char *argv[])
140{
141
142	return (_pam_exec(pamh, flags, argc, argv));
143}
144
145PAM_EXTERN int
146pam_sm_chauthtok(pam_handle_t *pamh, int flags,
147    int argc, const char *argv[])
148{
149
150	return (_pam_exec(pamh, flags, argc, argv));
151}
152
153PAM_MODULE_ENTRY("pam_exec");
154