xref: /freebsd/lib/libpam/modules/pam_ftpusers/pam_ftpusers.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2001 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by ThinkSec AS and
8  * NAI Labs, the Security Research Division of Network Associates, Inc.
9  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
10  * DARPA CHATS research program.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. The name of the author may not be used to endorse or promote
21  *    products derived from this software without specific prior written
22  *    permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <ctype.h>
41 #include <grp.h>
42 #include <paths.h>
43 #include <pwd.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 
48 #define PAM_SM_ACCOUNT
49 
50 #include <security/pam_appl.h>
51 #include <security/pam_modules.h>
52 #include <security/pam_mod_misc.h>
53 #include <security/openpam.h>
54 
55 PAM_EXTERN int
56 pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused,
57     int argc __unused, const char *argv[] __unused)
58 {
59 	struct passwd *pwd;
60 	struct group *grp;
61 	const char *user;
62 	int pam_err, found, allow;
63 	char *line, *name, **mem;
64 	size_t len, ulen;
65 	FILE *f;
66 
67 	pam_err = pam_get_user(pamh, &user, NULL);
68 	if (pam_err != PAM_SUCCESS)
69 		return (pam_err);
70 	if (user == NULL || (pwd = getpwnam(user)) == NULL)
71 		return (PAM_SERVICE_ERR);
72 
73 	found = 0;
74 	ulen = strlen(user);
75 	if ((f = fopen(_PATH_FTPUSERS, "r")) == NULL) {
76 		PAM_LOG("%s: %m", _PATH_FTPUSERS);
77 		goto done;
78 	}
79 	while (!found && (line = fgetln(f, &len)) != NULL) {
80 		if (*line == '#')
81 			continue;
82 		while (len > 0 && isspace(line[len - 1]))
83 			--len;
84 		if (len == 0)
85 			continue;
86 		/* simple case first */
87 		if (*line != '@') {
88 			if (len == ulen && strncmp(user, line, len) == 0)
89 				found = 1;
90 			continue;
91 		}
92 		/* member of specified group? */
93 		asprintf(&name, "%.*s", (int)len - 1, line + 1);
94 		if (name == NULL) {
95 			fclose(f);
96 			return (PAM_BUF_ERR);
97 		}
98 		grp = getgrnam(name);
99 		free(name);
100 		if (grp == NULL)
101 			continue;
102 		for (mem = grp->gr_mem; mem && *mem && !found; ++mem)
103 			if (strcmp(user, *mem) == 0)
104 				found = 1;
105 	}
106  done:
107 	allow = (openpam_get_option(pamh, "disallow") == NULL);
108 	if (found)
109 		pam_err = allow ? PAM_SUCCESS : PAM_AUTH_ERR;
110 	else
111 		pam_err = allow ? PAM_AUTH_ERR : PAM_SUCCESS;
112 	if (f != NULL)
113 		fclose(f);
114 	return (pam_err);
115 }
116 
117 PAM_MODULE_ENTRY("pam_ftpusers");
118