1 /*
2  * restorecond
3  *
4  * Copyright (C) 2006-2009 Red Hat
5  * see file 'COPYING' for use and warranty information
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; either version 2 of
10  * the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16 .*
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
20  * 02111-1307  USA
21  *
22  * Authors:
23  *   Dan Walsh <dwalsh@redhat.com>
24  *
25 */
26 
27 /*
28  * PURPOSE:
29  * This daemon program watches for the creation of files listed in a config file
30  * and makes sure that there security context matches the systems defaults
31  *
32  * USAGE:
33  * restorecond [-d] [-u] [-v] [-f restorecond_file ]
34  *
35  * -d   Run in debug mode
36  * -f   Use alternative restorecond_file
37  * -u   Run in user mode
38  * -v   Run in verbose mode (Report missing files)
39  *
40  * EXAMPLE USAGE:
41  * restorecond
42  *
43  */
44 
45 #define _GNU_SOURCE
46 #include <sys/inotify.h>
47 #include <errno.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <signal.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include "../setfiles/restore.h"
54 #include <sys/types.h>
55 #include <syslog.h>
56 #include <limits.h>
57 #include <pwd.h>
58 #include <sys/stat.h>
59 #include <string.h>
60 #include <stdio.h>
61 #include <fcntl.h>
62 #include "restorecond.h"
63 #include "utmpwatcher.h"
64 
65 const char *homedir;
66 static int master_fd = -1;
67 
68 static const char *server_watch_file  = "/etc/selinux/restorecond.conf";
69 static const char *user_watch_file  = "/etc/selinux/restorecond_user.conf";
70 static const char *watch_file;
71 static struct restore_opts r_opts;
72 
73 #include <selinux/selinux.h>
74 
75 int debug_mode = 0;
76 int terminate = 0;
77 int master_wd = -1;
78 int run_as_user = 0;
79 
done(void)80 static void done(void) {
81 	watch_list_free(master_fd);
82 	close(master_fd);
83 	utmpwatcher_free();
84 	matchpathcon_fini();
85 }
86 
87 static const char *pidfile = "/var/run/restorecond.pid";
88 
write_pid_file(void)89 static int write_pid_file(void)
90 {
91 	int pidfd, len;
92 	char val[16];
93 
94 	len = snprintf(val, sizeof(val), "%u\n", getpid());
95 	if (len < 0) {
96 		syslog(LOG_ERR, "Pid error (%s)", strerror(errno));
97 		pidfile = 0;
98 		return 1;
99 	}
100 	pidfd = open(pidfile, O_CREAT | O_TRUNC | O_NOFOLLOW | O_WRONLY, 0644);
101 	if (pidfd < 0) {
102 		syslog(LOG_ERR, "Unable to set pidfile (%s)", strerror(errno));
103 		pidfile = 0;
104 		return 1;
105 	}
106 	(void)write(pidfd, val, (unsigned int)len);
107 	close(pidfd);
108 	return 0;
109 }
110 
111 /*
112  * SIGTERM handler
113  */
term_handler(int s)114 static void term_handler(int s __attribute__ ((unused)))
115 {
116 	terminate = 1;
117 	/* trigger a failure in the watch */
118 	close(master_fd);
119 }
120 
usage(char * program)121 static void usage(char *program)
122 {
123 	printf("%s [-d] [-f restorecond_file ] [-u] [-v] \n", program);
124 }
125 
exitApp(const char * msg)126 void exitApp(const char *msg)
127 {
128 	perror(msg);
129 	exit(-1);
130 }
131 
132 /*
133    Add a file to the watch list.  We are watching for file creation, so we actually
134    put the watch on the directory and then examine all files created in that directory
135    to see if it is one that we are watching.
136 */
137 
main(int argc,char ** argv)138 int main(int argc, char **argv)
139 {
140 	int opt;
141 	struct sigaction sa;
142 
143 	memset(&r_opts, 0, sizeof(r_opts));
144 
145 	r_opts.progress = 0;
146 	r_opts.count = 0;
147 	r_opts.debug = 0;
148 	r_opts.change = 1;
149 	r_opts.verbose = 0;
150 	r_opts.logging = 0;
151 	r_opts.rootpath = NULL;
152 	r_opts.rootpathlen = 0;
153 	r_opts.outfile = NULL;
154 	r_opts.force = 0;
155 	r_opts.hard_links = 0;
156 	r_opts.abort_on_error = 0;
157 	r_opts.add_assoc = 0;
158 	r_opts.expand_realpath = 0;
159 	r_opts.fts_flags = FTS_PHYSICAL;
160 	r_opts.selabel_opt_validate = NULL;
161 	r_opts.selabel_opt_path = NULL;
162 	r_opts.ignore_enoent = 1;
163 
164 	restore_init(&r_opts);
165 	/* If we are not running SELinux then just exit */
166 	if (is_selinux_enabled() != 1) return 0;
167 
168 	/* Register sighandlers */
169 	sa.sa_flags = 0;
170 	sa.sa_handler = term_handler;
171 	sigemptyset(&sa.sa_mask);
172 	sigaction(SIGTERM, &sa, NULL);
173 
174 	set_matchpathcon_flags(MATCHPATHCON_NOTRANS);
175 
176 	exclude_non_seclabel_mounts();
177 	atexit( done );
178 	while ((opt = getopt(argc, argv, "hdf:uv")) > 0) {
179 		switch (opt) {
180 		case 'd':
181 			debug_mode = 1;
182 			break;
183 		case 'f':
184 			watch_file = optarg;
185 			break;
186 		case 'u':
187 			run_as_user = 1;
188 			break;
189 		case 'h':
190 			usage(argv[0]);
191 			exit(0);
192 			break;
193 		case 'v':
194 			r_opts.verbose++;
195 			break;
196 		case '?':
197 			usage(argv[0]);
198 			exit(-1);
199 		}
200 	}
201 
202 	master_fd = inotify_init();
203 	if (master_fd < 0)
204 		exitApp("inotify_init");
205 
206 	uid_t uid = getuid();
207 	struct passwd *pwd = getpwuid(uid);
208 	if (!pwd)
209 		exitApp("getpwuid");
210 
211 	homedir = pwd->pw_dir;
212 	if (uid != 0) {
213 		if (run_as_user)
214 			return server(master_fd, user_watch_file);
215 		if (start() != 0)
216 			return server(master_fd, user_watch_file);
217 		return 0;
218 	}
219 
220 	watch_file = server_watch_file;
221 	read_config(master_fd, watch_file);
222 
223 	if (!debug_mode)
224 		daemon(0, 0);
225 
226 	write_pid_file();
227 
228 	while (watch(master_fd, watch_file) == 0) {
229 	};
230 
231 	watch_list_free(master_fd);
232 	close(master_fd);
233 	matchpathcon_fini();
234 	if (pidfile)
235 		unlink(pidfile);
236 
237 	return 0;
238 }
239