xref: /freebsd/lib/libpam/modules/pam_ftpusers/pam_ftpusers.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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 #include <ctype.h>
39 #include <grp.h>
40 #include <paths.h>
41 #include <pwd.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #define PAM_SM_ACCOUNT
47 
48 #include <security/pam_appl.h>
49 #include <security/pam_modules.h>
50 #include <security/pam_mod_misc.h>
51 #include <security/openpam.h>
52 
53 PAM_EXTERN int
54 pam_sm_acct_mgmt(pam_handle_t *pamh, int flags __unused,
55     int argc __unused, const char *argv[] __unused)
56 {
57 	struct passwd *pwd;
58 	struct group *grp;
59 	const char *user;
60 	int pam_err, found, allow;
61 	char *line, *name, **mem;
62 	size_t len, ulen;
63 	FILE *f;
64 
65 	pam_err = pam_get_user(pamh, &user, NULL);
66 	if (pam_err != PAM_SUCCESS)
67 		return (pam_err);
68 	if (user == NULL || (pwd = getpwnam(user)) == NULL)
69 		return (PAM_SERVICE_ERR);
70 
71 	found = 0;
72 	ulen = strlen(user);
73 	if ((f = fopen(_PATH_FTPUSERS, "r")) == NULL) {
74 		PAM_LOG("%s: %m", _PATH_FTPUSERS);
75 		goto done;
76 	}
77 	while (!found && (line = fgetln(f, &len)) != NULL) {
78 		if (*line == '#')
79 			continue;
80 		while (len > 0 && isspace(line[len - 1]))
81 			--len;
82 		if (len == 0)
83 			continue;
84 		/* simple case first */
85 		if (*line != '@') {
86 			if (len == ulen && strncmp(user, line, len) == 0)
87 				found = 1;
88 			continue;
89 		}
90 		/* member of specified group? */
91 		asprintf(&name, "%.*s", (int)len - 1, line + 1);
92 		if (name == NULL) {
93 			fclose(f);
94 			return (PAM_BUF_ERR);
95 		}
96 		grp = getgrnam(name);
97 		free(name);
98 		if (grp == NULL)
99 			continue;
100 		for (mem = grp->gr_mem; mem && *mem && !found; ++mem)
101 			if (strcmp(user, *mem) == 0)
102 				found = 1;
103 	}
104  done:
105 	allow = (openpam_get_option(pamh, "disallow") == NULL);
106 	if (found)
107 		pam_err = allow ? PAM_SUCCESS : PAM_AUTH_ERR;
108 	else
109 		pam_err = allow ? PAM_AUTH_ERR : PAM_SUCCESS;
110 	if (f != NULL)
111 		fclose(f);
112 	return (pam_err);
113 }
114 
115 PAM_MODULE_ENTRY("pam_ftpusers");
116