xref: /aosp_15_r20/external/selinux/policycoreutils/setfiles/setfiles.c (revision 2d543d20722ada2425b5bdab9d0d1d29470e7bba)
1 #include "restore.h"
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <fcntl.h>
5 #include <stdio_ext.h>
6 #include <ctype.h>
7 #include <regex.h>
8 #include <sys/vfs.h>
9 #include <libgen.h>
10 #ifdef USE_AUDIT
11 #include <libaudit.h>
12 
13 #ifndef AUDIT_FS_RELABEL
14 #define AUDIT_FS_RELABEL 2309
15 #endif
16 #endif
17 
18 static char *policyfile;
19 static int warn_no_match;
20 static int null_terminated;
21 static int request_digest;
22 static struct restore_opts r_opts;
23 
24 #define STAT_BLOCK_SIZE 1
25 
26 #define SETFILES "setfiles"
27 #define RESTORECON "restorecon"
28 static int iamrestorecon;
29 
30 /* Behavior flags determined based on setfiles vs. restorecon */
31 static int ctx_validate; /* Validate contexts */
32 static const char *altpath; /* Alternate path to file_contexts */
33 
usage(const char * const name)34 static __attribute__((__noreturn__)) void usage(const char *const name)
35 {
36 	if (iamrestorecon) {
37 		fprintf(stderr,
38 			"usage:  %s [-iIDFmnprRv0xT] [-e excludedir] pathname...\n"
39 			"usage:  %s [-iIDFmnprRv0xT] [-e excludedir] -f filename\n",
40 			name, name);
41 	} else {
42 		fprintf(stderr,
43 			"usage:  %s [-diIDlmnpqvCEFWT] [-e excludedir] [-r alt_root_path] [-c policyfile] spec_file pathname...\n"
44 			"usage:  %s [-diIDlmnpqvCEFWT] [-e excludedir] [-r alt_root_path] [-c policyfile] spec_file -f filename\n"
45 			"usage:  %s -s [-diIDlmnpqvFWT] spec_file\n",
46 			name, name, name);
47 	}
48 	exit(-1);
49 }
50 
set_rootpath(const char * arg)51 static void set_rootpath(const char *arg)
52 {
53 	if (strlen(arg) == 1 && strncmp(arg, "/", 1) == 0) {
54 		fprintf(stderr, "%s:  invalid alt_rootpath: %s\n",
55 			r_opts.progname, arg);
56 		exit(-1);
57 	}
58 
59 	r_opts.rootpath = strdup(arg);
60 	if (!r_opts.rootpath) {
61 		fprintf(stderr,
62 			"%s:  insufficient memory for r_opts.rootpath\n",
63 			r_opts.progname);
64 		exit(-1);
65 	}
66 }
67 
canoncon(char ** contextp)68 static int canoncon(char **contextp)
69 {
70 	char *context = *contextp, *tmpcon;
71 	int rc = 0;
72 
73 	if (policyfile) {
74 		if (sepol_check_context(context) < 0) {
75 			fprintf(stderr, "invalid context %s\n", context);
76 			exit(-1);
77 		}
78 	} else if (security_canonicalize_context_raw(context, &tmpcon) == 0) {
79 		free(context);
80 		*contextp = tmpcon;
81 	} else if (errno != ENOENT) {
82 		rc = -1;
83 	}
84 
85 	return rc;
86 }
87 
88 #ifndef USE_AUDIT
audit_mass_relabel(int mass_relabel_errs)89 static void audit_mass_relabel(int mass_relabel_errs __attribute__((unused)))
90 {
91 #else
92 static void audit_mass_relabel(int mass_relabel_errs)
93 {
94 	int audit_fd = -1;
95 	int rc = 0;
96 
97 	audit_fd = audit_open();
98 
99 	if (audit_fd < 0) {
100 		fprintf(stderr, "Error connecting to audit system: %s.\n",
101 			strerror(errno));
102 		return;
103 	}
104 
105 	rc = audit_log_user_message(audit_fd, AUDIT_FS_RELABEL,
106 				    "op=mass relabel",
107 				    NULL, NULL, NULL, !mass_relabel_errs);
108 	if (rc <= 0) {
109 		fprintf(stderr, "Error sending audit message: %s.\n",
110 			strerror(errno));
111 		/* exit(-1); -- don't exit atm. as fix for eff_cap isn't
112 		 * in most kernels.
113 		 */
114 	}
115 	audit_close(audit_fd);
116 #endif
117 }
118 
119 static int __attribute__ ((format(printf, 2, 3)))
120 log_callback(int type, const char *fmt, ...)
121 {
122 	int rc;
123 	FILE *out;
124 	va_list ap;
125 
126 	if (type == SELINUX_INFO) {
127 		out = stdout;
128 	} else {
129 		out = stderr;
130 		fflush(stdout);
131 		fprintf(out, "%s: ", r_opts.progname);
132 	}
133 	va_start(ap, fmt);
134 	rc = vfprintf(out, fmt, ap);
135 	va_end(ap);
136 	return rc;
137 }
138 
139 int main(int argc, char **argv)
140 {
141 	struct stat sb;
142 	int opt, i = 0;
143 	const char *input_filename = NULL;
144 	int use_input_file = 0;
145 	char *buf = NULL, *endptr;
146 	size_t buf_len, nthreads = 1;
147 	const char *base;
148 	int errors = 0;
149 	const char *ropts = "e:f:hiIDlmno:pqrsvFRW0xT:";
150 	const char *sopts = "c:de:f:hiIDlmno:pqr:svCEFR:W0T:";
151 	const char *opts;
152 	union selinux_callback cb;
153 	long unsigned skipped_errors;
154 
155 	/* Initialize variables */
156 	memset(&r_opts, 0, sizeof(r_opts));
157 	altpath = NULL;
158 	null_terminated = 0;
159 	warn_no_match = 0;
160 	request_digest = 0;
161 	policyfile = NULL;
162 	skipped_errors = 0;
163 
164 	if (!argv[0]) {
165 		fprintf(stderr, "Called without required program name!\n");
166 		exit(-1);
167 	}
168 	r_opts.progname = strdup(argv[0]);
169 	if (!r_opts.progname) {
170 		fprintf(stderr, "%s:  Out of memory!\n", argv[0]);
171 		exit(-1);
172 	}
173 	base = basename(r_opts.progname);
174 
175 	if (!strcmp(base, SETFILES)) {
176 		/*
177 		 * setfiles:
178 		 * Recursive descent,
179 		 * Does not expand paths via realpath,
180 		 * Try to track inode associations for conflict detection,
181 		 * Does not follow mounts (sets SELINUX_RESTORECON_XDEV),
182 		 * Validates all file contexts at init time.
183 		 */
184 		iamrestorecon = 0;
185 		r_opts.recurse = SELINUX_RESTORECON_RECURSE;
186 		r_opts.userealpath = 0; /* SELINUX_RESTORECON_REALPATH */
187 		r_opts.add_assoc = SELINUX_RESTORECON_ADD_ASSOC;
188 		/* FTS_PHYSICAL and FTS_NOCHDIR are always set by selinux_restorecon(3) */
189 		r_opts.xdev = SELINUX_RESTORECON_XDEV;
190 		r_opts.ignore_mounts = 0; /* SELINUX_RESTORECON_IGNORE_MOUNTS */
191 		ctx_validate = 1;
192 		opts = sopts;
193 	} else {
194 		/*
195 		 * restorecon:
196 		 * No recursive descent unless -r/-R,
197 		 * Expands paths via realpath,
198 		 * Do not try to track inode associations for conflict detection,
199 		 * Follows mounts,
200 		 * Does lazy validation of contexts upon use.
201 		 */
202 		if (strcmp(base, RESTORECON))
203 			fprintf(stderr, "Executed with unrecognized name (%s), defaulting to %s behavior.\n",
204 				base, RESTORECON);
205 
206 		iamrestorecon = 1;
207 		r_opts.recurse = 0;
208 		r_opts.userealpath = SELINUX_RESTORECON_REALPATH;
209 		r_opts.add_assoc = 0;
210 		r_opts.xdev = 0;
211 		r_opts.ignore_mounts = 0;
212 		ctx_validate = 0;
213 		opts = ropts;
214 
215 		/* restorecon only:  silent exit if no SELinux.
216 		 * Allows unconditional execution by scripts.
217 		 */
218 		if (is_selinux_enabled() <= 0)
219 			exit(0);
220 	}
221 
222 	/* Process any options. */
223 	while ((opt = getopt(argc, argv, opts)) > 0) {
224 		switch (opt) {
225 		case 'c':
226 			{
227 				FILE *policystream;
228 
229 				policyfile = optarg;
230 
231 				policystream = fopen(policyfile, "r");
232 				if (!policystream) {
233 					fprintf(stderr,
234 						"Error opening %s: %s\n",
235 						policyfile, strerror(errno));
236 					exit(-1);
237 				}
238 				__fsetlocking(policystream,
239 					      FSETLOCKING_BYCALLER);
240 
241 				if (sepol_set_policydb_from_file(policystream)
242 									< 0) {
243 					fprintf(stderr,
244 						"Error reading policy %s: %s\n",
245 						policyfile, strerror(errno));
246 					exit(-1);
247 				}
248 				fclose(policystream);
249 
250 				ctx_validate = 1;
251 				break;
252 			}
253 		case 'e':
254 			if (lstat(optarg, &sb) < 0 && errno != EACCES) {
255 				fprintf(stderr, "Can't stat exclude path \"%s\", %s - ignoring.\n",
256 					optarg, strerror(errno));
257 				break;
258 			}
259 			add_exclude(optarg);
260 			break;
261 		case 'f':
262 			use_input_file = 1;
263 			input_filename = optarg;
264 			break;
265 		case 'd':
266 			r_opts.debug = 1;
267 			r_opts.log_matches =
268 					   SELINUX_RESTORECON_LOG_MATCHES;
269 			break;
270 		case 'i':
271 			r_opts.ignore_noent =
272 					   SELINUX_RESTORECON_IGNORE_NOENTRY;
273 			break;
274 		case 'I': /* Force label check by ignoring directory digest. */
275 			r_opts.ignore_digest =
276 					   SELINUX_RESTORECON_IGNORE_DIGEST;
277 			request_digest = 1;
278 			break;
279 		case 'D': /*
280 			   * Request file_contexts digest in selabel_open
281 			   * This will effectively enable usage of the
282 			   * security.restorecon_last extended attribute.
283 			   */
284 			request_digest = 1;
285 			break;
286 		case 'l':
287 			r_opts.syslog_changes =
288 					   SELINUX_RESTORECON_SYSLOG_CHANGES;
289 			break;
290 		case 'C':
291 			r_opts.count_errors = SELINUX_RESTORECON_COUNT_ERRORS;
292 			break;
293 		case 'E':
294 			r_opts.conflict_error =
295 					   SELINUX_RESTORECON_CONFLICT_ERROR;
296 			break;
297 		case 'F':
298 			r_opts.set_specctx =
299 					   SELINUX_RESTORECON_SET_SPECFILE_CTX;
300 			break;
301 		case 'm':
302 			r_opts.ignore_mounts =
303 					   SELINUX_RESTORECON_IGNORE_MOUNTS;
304 			break;
305 		case 'n':
306 			r_opts.nochange = SELINUX_RESTORECON_NOCHANGE;
307 			break;
308 		case 'o': /* Deprecated */
309 			fprintf(stderr, "%s: -o option no longer supported\n",
310 				r_opts.progname);
311 			break;
312 		case 'q':
313 			/* Deprecated - Was only used to say whether print
314 			 * filespec_eval() params. Now uses verbose flag.
315 			 */
316 			break;
317 		case 'R':
318 		case 'r':
319 			if (iamrestorecon) {
320 				r_opts.recurse = SELINUX_RESTORECON_RECURSE;
321 				break;
322 			}
323 
324 			if (lstat(optarg, &sb) < 0 && errno != EACCES) {
325 				fprintf(stderr,
326 					"Can't stat alt_root_path \"%s\", %s\n",
327 					optarg, strerror(errno));
328 				exit(-1);
329 			}
330 
331 			if (r_opts.rootpath) {
332 				fprintf(stderr,
333 					"%s: only one -r can be specified\n",
334 					argv[0]);
335 				exit(-1);
336 			}
337 			set_rootpath(optarg);
338 			break;
339 		case 's':
340 			use_input_file = 1;
341 			input_filename = "-";
342 			r_opts.add_assoc = 0;
343 			break;
344 		case 'v':
345 			if (r_opts.progress) {
346 				fprintf(stderr,
347 					"Progress and Verbose mutually exclusive\n");
348 				usage(argv[0]);
349 			}
350 			r_opts.verbose = SELINUX_RESTORECON_VERBOSE;
351 			break;
352 		case 'p':
353 			if (r_opts.verbose) {
354 				fprintf(stderr,
355 					"Progress and Verbose mutually exclusive\n");
356 				usage(argv[0]);
357 			}
358 			r_opts.progress = SELINUX_RESTORECON_PROGRESS;
359 			break;
360 		case 'W':
361 			warn_no_match = 1; /* Print selabel_stats() */
362 			break;
363 		case '0':
364 			null_terminated = 1;
365 			break;
366 		case 'x':
367 			r_opts.xdev = SELINUX_RESTORECON_XDEV;
368 			break;
369 		case 'T':
370 			nthreads = strtoull(optarg, &endptr, 10);
371 			if (*optarg == '\0' || *endptr != '\0')
372 				usage(argv[0]);
373 			break;
374 		case 'h':
375 		case '?':
376 			usage(argv[0]);
377 		}
378 	}
379 
380 	for (i = optind; i < argc; i++) {
381 		if (!strcmp(argv[i], "/"))
382 			r_opts.mass_relabel = SELINUX_RESTORECON_MASS_RELABEL;
383 	}
384 
385 	cb.func_log = log_callback;
386 	selinux_set_callback(SELINUX_CB_LOG, cb);
387 
388 	if (!iamrestorecon) {
389 		if (policyfile) {
390 			if (optind > (argc - 1))
391 				usage(argv[0]);
392 		} else if (use_input_file) {
393 			if (optind != (argc - 1)) {
394 				/* Cannot mix with pathname arguments. */
395 				usage(argv[0]);
396 			}
397 		} else {
398 			if (optind > (argc - 2))
399 				usage(argv[0]);
400 		}
401 
402 		/* Use our own invalid context checking function so that
403 		 * we can support either checking against the active policy or
404 		 * checking against a binary policy file.
405 		 */
406 		cb.func_validate = canoncon;
407 		selinux_set_callback(SELINUX_CB_VALIDATE, cb);
408 
409 		if (stat(argv[optind], &sb) < 0) {
410 			perror(argv[optind]);
411 			exit(-1);
412 		}
413 		if (!S_ISREG(sb.st_mode)) {
414 			fprintf(stderr, "%s:  spec file %s is not a regular file.\n",
415 				argv[0], argv[optind]);
416 			exit(-1);
417 		}
418 
419 		altpath = argv[optind];
420 		optind++;
421 	} else if (argc < 2)
422 		usage(argv[0]);
423 
424 	/* Set selabel_open options. */
425 	r_opts.selabel_opt_validate = (ctx_validate ? (char *)1 : NULL);
426 	r_opts.selabel_opt_digest = (request_digest ? (char *)1 : NULL);
427 	r_opts.selabel_opt_path = altpath;
428 
429 	restore_init(&r_opts);
430 
431 	if (use_input_file) {
432 		FILE *f = stdin;
433 		ssize_t len;
434 		int delim;
435 
436 		if (strcmp(input_filename, "-") != 0)
437 			f = fopen(input_filename, "r");
438 
439 		if (f == NULL) {
440 			fprintf(stderr, "Unable to open %s: %s\n",
441 				input_filename,
442 				strerror(errno));
443 			usage(argv[0]);
444 		}
445 		__fsetlocking(f, FSETLOCKING_BYCALLER);
446 
447 		delim = (null_terminated != 0) ? '\0' : '\n';
448 		while ((len = getdelim(&buf, &buf_len, delim, f)) > 0) {
449 			buf[len - 1] = 0;
450 			if (!strcmp(buf, "/"))
451 				r_opts.mass_relabel = SELINUX_RESTORECON_MASS_RELABEL;
452 			errors |= process_glob(buf, &r_opts, nthreads,
453 					       &skipped_errors) < 0;
454 		}
455 		if (strcmp(input_filename, "-") != 0)
456 			fclose(f);
457 	} else {
458 		for (i = optind; i < argc; i++)
459 			errors |= process_glob(argv[i], &r_opts, nthreads,
460 					       &skipped_errors) < 0;
461 	}
462 
463 	if (r_opts.mass_relabel && !r_opts.nochange)
464 		audit_mass_relabel(errors);
465 
466 	if (warn_no_match)
467 		selabel_stats(r_opts.hnd);
468 
469 	selabel_close(r_opts.hnd);
470 	restore_finish();
471 
472 	if (r_opts.progress)
473 		fprintf(stdout, "\n");
474 
475 	exit(errors ? -1 : skipped_errors ? 1 : 0);
476 }
477