Contents of /tags/mkinitrd-6_1_3/busybox/selinux/setfiles.c
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Mon May 4 18:51:23 2009 UTC (15 years, 4 months ago) by niro
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Mon May 4 18:51:23 2009 UTC (15 years, 4 months ago) by niro
File MIME type: text/plain
File size: 15876 byte(s)
tagged 'mkinitrd-6_1_3'
1 | /* |
2 | setfiles: based on policycoreutils 2.0.19 |
3 | policycoreutils was released under GPL 2. |
4 | Port to BusyBox (c) 2007 by Yuichi Nakamura <ynakam@hitachisoft.jp> |
5 | */ |
6 | |
7 | #include "libbb.h" |
8 | #if ENABLE_FEATURE_SETFILES_CHECK_OPTION |
9 | #include <sepol/sepol.h> |
10 | #endif |
11 | |
12 | #define MAX_EXCLUDES 50 |
13 | |
14 | struct edir { |
15 | char *directory; |
16 | size_t size; |
17 | }; |
18 | |
19 | struct globals { |
20 | FILE *outfile; |
21 | char *policyfile; |
22 | char *rootpath; |
23 | int rootpathlen; |
24 | unsigned count; |
25 | int excludeCtr; |
26 | int errors; |
27 | int verbose; /* getopt32 uses it, has to be int */ |
28 | smallint recurse; /* Recursive descent */ |
29 | smallint follow_mounts; |
30 | /* Behavior flags determined based on setfiles vs. restorecon */ |
31 | smallint expand_realpath; /* Expand paths via realpath */ |
32 | smallint abort_on_error; /* Abort the file tree walk upon an error */ |
33 | int add_assoc; /* Track inode associations for conflict detection */ |
34 | int matchpathcon_flags; /* Flags to matchpathcon */ |
35 | dev_t dev_id; /* Device id where target file exists */ |
36 | int nerr; |
37 | struct edir excludeArray[MAX_EXCLUDES]; |
38 | }; |
39 | |
40 | #define G (*(struct globals*)&bb_common_bufsiz1) |
41 | void BUG_setfiles_globals_too_big(void); |
42 | #define INIT_G() do { \ |
43 | if (sizeof(G) > COMMON_BUFSIZE) \ |
44 | BUG_setfiles_globals_too_big(); \ |
45 | /* memset(&G, 0, sizeof(G)); - already is */ \ |
46 | } while (0) |
47 | #define outfile (G.outfile ) |
48 | #define policyfile (G.policyfile ) |
49 | #define rootpath (G.rootpath ) |
50 | #define rootpathlen (G.rootpathlen ) |
51 | #define count (G.count ) |
52 | #define excludeCtr (G.excludeCtr ) |
53 | #define errors (G.errors ) |
54 | #define verbose (G.verbose ) |
55 | #define recurse (G.recurse ) |
56 | #define follow_mounts (G.follow_mounts ) |
57 | #define expand_realpath (G.expand_realpath ) |
58 | #define abort_on_error (G.abort_on_error ) |
59 | #define add_assoc (G.add_assoc ) |
60 | #define matchpathcon_flags (G.matchpathcon_flags) |
61 | #define dev_id (G.dev_id ) |
62 | #define nerr (G.nerr ) |
63 | #define excludeArray (G.excludeArray ) |
64 | |
65 | /* Must match getopt32 string! */ |
66 | enum { |
67 | OPT_d = (1 << 0), |
68 | OPT_e = (1 << 1), |
69 | OPT_f = (1 << 2), |
70 | OPT_i = (1 << 3), |
71 | OPT_l = (1 << 4), |
72 | OPT_n = (1 << 5), |
73 | OPT_p = (1 << 6), |
74 | OPT_q = (1 << 7), |
75 | OPT_r = (1 << 8), |
76 | OPT_s = (1 << 9), |
77 | OPT_v = (1 << 10), |
78 | OPT_o = (1 << 11), |
79 | OPT_F = (1 << 12), |
80 | OPT_W = (1 << 13), |
81 | OPT_c = (1 << 14), /* c only for setfiles */ |
82 | OPT_R = (1 << 14), /* R only for restorecon */ |
83 | }; |
84 | #define FLAG_d_debug (option_mask32 & OPT_d) |
85 | #define FLAG_e (option_mask32 & OPT_e) |
86 | #define FLAG_f (option_mask32 & OPT_f) |
87 | #define FLAG_i_ignore_enoent (option_mask32 & OPT_i) |
88 | #define FLAG_l_take_log (option_mask32 & OPT_l) |
89 | #define FLAG_n_dry_run (option_mask32 & OPT_n) |
90 | #define FLAG_p_progress (option_mask32 & OPT_p) |
91 | #define FLAG_q_quiet (option_mask32 & OPT_q) |
92 | #define FLAG_r (option_mask32 & OPT_r) |
93 | #define FLAG_s (option_mask32 & OPT_s) |
94 | #define FLAG_v (option_mask32 & OPT_v) |
95 | #define FLAG_o (option_mask32 & OPT_o) |
96 | #define FLAG_F_force (option_mask32 & OPT_F) |
97 | #define FLAG_W_warn_no_match (option_mask32 & OPT_W) |
98 | #define FLAG_c (option_mask32 & OPT_c) |
99 | #define FLAG_R (option_mask32 & OPT_R) |
100 | |
101 | |
102 | static void qprintf(const char *fmt UNUSED_PARAM, ...) |
103 | { |
104 | /* quiet, do nothing */ |
105 | } |
106 | |
107 | static void inc_err(void) |
108 | { |
109 | nerr++; |
110 | if (nerr > 9 && !FLAG_d_debug) { |
111 | bb_error_msg_and_die("exiting after 10 errors"); |
112 | } |
113 | } |
114 | |
115 | static void add_exclude(const char *const directory) |
116 | { |
117 | struct stat sb; |
118 | size_t len; |
119 | |
120 | if (directory == NULL || directory[0] != '/') { |
121 | bb_error_msg_and_die("full path required for exclude: %s", directory); |
122 | |
123 | } |
124 | if (lstat(directory, &sb)) { |
125 | bb_error_msg("directory \"%s\" not found, ignoring", directory); |
126 | return; |
127 | } |
128 | if ((sb.st_mode & S_IFDIR) == 0) { |
129 | bb_error_msg("\"%s\" is not a directory: mode %o, ignoring", |
130 | directory, sb.st_mode); |
131 | return; |
132 | } |
133 | if (excludeCtr == MAX_EXCLUDES) { |
134 | bb_error_msg_and_die("maximum excludes %d exceeded", MAX_EXCLUDES); |
135 | } |
136 | |
137 | len = strlen(directory); |
138 | while (len > 1 && directory[len - 1] == '/') { |
139 | len--; |
140 | } |
141 | excludeArray[excludeCtr].directory = xstrndup(directory, len); |
142 | excludeArray[excludeCtr++].size = len; |
143 | } |
144 | |
145 | static bool exclude(const char *file) |
146 | { |
147 | int i = 0; |
148 | for (i = 0; i < excludeCtr; i++) { |
149 | if (strncmp(file, excludeArray[i].directory, |
150 | excludeArray[i].size) == 0) { |
151 | if (file[excludeArray[i].size] == '\0' |
152 | || file[excludeArray[i].size] == '/') { |
153 | return 1; |
154 | } |
155 | } |
156 | } |
157 | return 0; |
158 | } |
159 | |
160 | static int match(const char *name, struct stat *sb, char **con) |
161 | { |
162 | int ret; |
163 | char path[PATH_MAX + 1]; |
164 | char *tmp_path = xstrdup(name); |
165 | |
166 | if (excludeCtr > 0 && exclude(name)) { |
167 | goto err; |
168 | } |
169 | ret = lstat(name, sb); |
170 | if (ret) { |
171 | if (FLAG_i_ignore_enoent && errno == ENOENT) { |
172 | free(tmp_path); |
173 | return 0; |
174 | } |
175 | bb_error_msg("stat(%s)", name); |
176 | goto err; |
177 | } |
178 | |
179 | if (expand_realpath) { |
180 | if (S_ISLNK(sb->st_mode)) { |
181 | char *p = NULL; |
182 | char *file_sep; |
183 | |
184 | size_t len = 0; |
185 | |
186 | if (verbose > 1) |
187 | bb_error_msg("warning! %s refers to a symbolic link, not following last component", name); |
188 | |
189 | file_sep = strrchr(tmp_path, '/'); |
190 | if (file_sep == tmp_path) { |
191 | file_sep++; |
192 | path[0] = '\0'; |
193 | p = path; |
194 | } else if (file_sep) { |
195 | *file_sep++ = '\0'; |
196 | p = realpath(tmp_path, path); |
197 | } else { |
198 | file_sep = tmp_path; |
199 | p = realpath("./", path); |
200 | } |
201 | if (p) |
202 | len = strlen(p); |
203 | if (!p || len + strlen(file_sep) + 2 > PATH_MAX) { |
204 | bb_perror_msg("realpath(%s) failed", name); |
205 | goto err; |
206 | } |
207 | p += len; |
208 | /* ensure trailing slash of directory name */ |
209 | if (len == 0 || p[-1] != '/') { |
210 | *p++ = '/'; |
211 | } |
212 | strcpy(p, file_sep); |
213 | name = path; |
214 | if (excludeCtr > 0 && exclude(name)) |
215 | goto err; |
216 | |
217 | } else { |
218 | char *p; |
219 | p = realpath(name, path); |
220 | if (!p) { |
221 | bb_perror_msg("realpath(%s)", name); |
222 | goto err; |
223 | } |
224 | name = p; |
225 | if (excludeCtr > 0 && exclude(name)) |
226 | goto err; |
227 | } |
228 | } |
229 | |
230 | /* name will be what is matched in the policy */ |
231 | if (NULL != rootpath) { |
232 | if (0 != strncmp(rootpath, name, rootpathlen)) { |
233 | bb_error_msg("%s is not located in %s", |
234 | name, rootpath); |
235 | goto err; |
236 | } |
237 | name += rootpathlen; |
238 | } |
239 | |
240 | free(tmp_path); |
241 | if (rootpath != NULL && name[0] == '\0') |
242 | /* this is actually the root dir of the alt root */ |
243 | return matchpathcon_index("/", sb->st_mode, con); |
244 | return matchpathcon_index(name, sb->st_mode, con); |
245 | err: |
246 | free(tmp_path); |
247 | return -1; |
248 | } |
249 | |
250 | /* Compare two contexts to see if their differences are "significant", |
251 | * or whether the only difference is in the user. */ |
252 | static bool only_changed_user(const char *a, const char *b) |
253 | { |
254 | if (FLAG_F_force) |
255 | return 0; |
256 | if (!a || !b) |
257 | return 0; |
258 | a = strchr(a, ':'); /* Rest of the context after the user */ |
259 | b = strchr(b, ':'); |
260 | if (!a || !b) |
261 | return 0; |
262 | return (strcmp(a, b) == 0); |
263 | } |
264 | |
265 | static int restore(const char *file) |
266 | { |
267 | char *my_file; |
268 | struct stat my_sb; |
269 | int i, j, ret; |
270 | char *context = NULL; |
271 | char *newcon = NULL; |
272 | bool user_only_changed = 0; |
273 | int retval = 0; |
274 | |
275 | my_file = bb_simplify_path(file); |
276 | |
277 | i = match(my_file, &my_sb, &newcon); |
278 | |
279 | if (i < 0) /* No matching specification. */ |
280 | goto out; |
281 | |
282 | if (FLAG_p_progress) { |
283 | count++; |
284 | if (count % 0x400 == 0) { /* every 1024 times */ |
285 | count = (count % (80*0x400)); |
286 | if (count == 0) |
287 | bb_putchar('\n'); |
288 | bb_putchar('*'); |
289 | fflush(stdout); |
290 | } |
291 | } |
292 | |
293 | /* |
294 | * Try to add an association between this inode and |
295 | * this specification. If there is already an association |
296 | * for this inode and it conflicts with this specification, |
297 | * then use the last matching specification. |
298 | */ |
299 | if (add_assoc) { |
300 | j = matchpathcon_filespec_add(my_sb.st_ino, i, my_file); |
301 | if (j < 0) |
302 | goto err; |
303 | |
304 | if (j != i) { |
305 | /* There was already an association and it took precedence. */ |
306 | goto out; |
307 | } |
308 | } |
309 | |
310 | if (FLAG_d_debug) |
311 | printf("%s: %s matched by %s\n", applet_name, my_file, newcon); |
312 | |
313 | /* Get the current context of the file. */ |
314 | ret = lgetfilecon_raw(my_file, &context); |
315 | if (ret < 0) { |
316 | if (errno == ENODATA) { |
317 | context = NULL; /* paranoia */ |
318 | } else { |
319 | bb_perror_msg("lgetfilecon_raw on %s", my_file); |
320 | goto err; |
321 | } |
322 | user_only_changed = 0; |
323 | } else |
324 | user_only_changed = only_changed_user(context, newcon); |
325 | |
326 | /* |
327 | * Do not relabel the file if the matching specification is |
328 | * <<none>> or the file is already labeled according to the |
329 | * specification. |
330 | */ |
331 | if ((strcmp(newcon, "<<none>>") == 0) |
332 | || (context && (strcmp(context, newcon) == 0) && !FLAG_F_force)) { |
333 | goto out; |
334 | } |
335 | |
336 | if (!FLAG_F_force && context && (is_context_customizable(context) > 0)) { |
337 | if (verbose > 1) { |
338 | bb_error_msg("skipping %s. %s is customizable_types", |
339 | my_file, context); |
340 | } |
341 | goto out; |
342 | } |
343 | |
344 | if (verbose) { |
345 | /* If we're just doing "-v", trim out any relabels where |
346 | * the user has changed but the role and type are the |
347 | * same. For "-vv", emit everything. */ |
348 | if (verbose > 1 || !user_only_changed) { |
349 | bb_info_msg("%s: reset %s context %s->%s", |
350 | applet_name, my_file, context ?: "", newcon); |
351 | } |
352 | } |
353 | |
354 | if (FLAG_l_take_log && !user_only_changed) { |
355 | if (context) |
356 | bb_info_msg("relabeling %s from %s to %s", my_file, context, newcon); |
357 | else |
358 | bb_info_msg("labeling %s to %s", my_file, newcon); |
359 | } |
360 | |
361 | if (outfile && !user_only_changed) |
362 | fprintf(outfile, "%s\n", my_file); |
363 | |
364 | /* |
365 | * Do not relabel the file if -n was used. |
366 | */ |
367 | if (FLAG_n_dry_run || user_only_changed) |
368 | goto out; |
369 | |
370 | /* |
371 | * Relabel the file to the specified context. |
372 | */ |
373 | ret = lsetfilecon(my_file, newcon); |
374 | if (ret) { |
375 | bb_perror_msg("lsetfileconon(%s,%s)", my_file, newcon); |
376 | goto err; |
377 | } |
378 | |
379 | out: |
380 | freecon(context); |
381 | freecon(newcon); |
382 | free(my_file); |
383 | return retval; |
384 | err: |
385 | retval--; /* -1 */ |
386 | goto out; |
387 | } |
388 | |
389 | /* |
390 | * Apply the last matching specification to a file. |
391 | * This function is called by recursive_action on each file during |
392 | * the directory traversal. |
393 | */ |
394 | static int FAST_FUNC apply_spec( |
395 | const char *file, |
396 | struct stat *sb, |
397 | void *userData UNUSED_PARAM, |
398 | int depth UNUSED_PARAM) |
399 | { |
400 | if (!follow_mounts) { |
401 | /* setfiles does not process across different mount points */ |
402 | if (sb->st_dev != dev_id) { |
403 | return SKIP; |
404 | } |
405 | } |
406 | errors |= restore(file); |
407 | if (abort_on_error && errors) |
408 | return FALSE; |
409 | return TRUE; |
410 | } |
411 | |
412 | |
413 | static int canoncon(const char *path, unsigned lineno, char **contextp) |
414 | { |
415 | static const char err_msg[] ALIGN1 = "%s: line %u has invalid context %s"; |
416 | |
417 | char *tmpcon; |
418 | char *context = *contextp; |
419 | int invalid = 0; |
420 | |
421 | #if ENABLE_FEATURE_SETFILES_CHECK_OPTION |
422 | if (policyfile) { |
423 | if (sepol_check_context(context) >= 0) |
424 | return 0; |
425 | /* Exit immediately if we're in checking mode. */ |
426 | bb_error_msg_and_die(err_msg, path, lineno, context); |
427 | } |
428 | #endif |
429 | |
430 | if (security_canonicalize_context_raw(context, &tmpcon) < 0) { |
431 | if (errno != ENOENT) { |
432 | invalid = 1; |
433 | inc_err(); |
434 | } |
435 | } else { |
436 | free(context); |
437 | *contextp = tmpcon; |
438 | } |
439 | |
440 | if (invalid) { |
441 | bb_error_msg(err_msg, path, lineno, context); |
442 | } |
443 | |
444 | return invalid; |
445 | } |
446 | |
447 | static int process_one(char *name) |
448 | { |
449 | struct stat sb; |
450 | int rc; |
451 | |
452 | rc = lstat(name, &sb); |
453 | if (rc < 0) { |
454 | if (FLAG_i_ignore_enoent && errno == ENOENT) |
455 | return 0; |
456 | bb_perror_msg("stat(%s)", name); |
457 | goto err; |
458 | } |
459 | dev_id = sb.st_dev; |
460 | |
461 | if (S_ISDIR(sb.st_mode) && recurse) { |
462 | if (recursive_action(name, |
463 | ACTION_RECURSE, |
464 | apply_spec, |
465 | apply_spec, |
466 | NULL, 0) != TRUE) { |
467 | bb_error_msg("error while labeling %s", name); |
468 | goto err; |
469 | } |
470 | } else { |
471 | rc = restore(name); |
472 | if (rc) |
473 | goto err; |
474 | } |
475 | |
476 | out: |
477 | if (add_assoc) { |
478 | if (FLAG_q_quiet) |
479 | set_matchpathcon_printf(&qprintf); |
480 | matchpathcon_filespec_eval(); |
481 | set_matchpathcon_printf(NULL); |
482 | matchpathcon_filespec_destroy(); |
483 | } |
484 | |
485 | return rc; |
486 | |
487 | err: |
488 | rc = -1; |
489 | goto out; |
490 | } |
491 | |
492 | int setfiles_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
493 | int setfiles_main(int argc, char **argv) |
494 | { |
495 | struct stat sb; |
496 | int rc, i = 0; |
497 | const char *input_filename = NULL; |
498 | char *buf = NULL; |
499 | size_t buf_len; |
500 | int flags; |
501 | llist_t *exclude_dir = NULL; |
502 | char *out_filename = NULL; |
503 | |
504 | INIT_G(); |
505 | |
506 | if (applet_name[0] == 's') { /* "setfiles" */ |
507 | /* |
508 | * setfiles: |
509 | * Recursive descent, |
510 | * Does not expand paths via realpath, |
511 | * Aborts on errors during the file tree walk, |
512 | * Try to track inode associations for conflict detection, |
513 | * Does not follow mounts, |
514 | * Validates all file contexts at init time. |
515 | */ |
516 | recurse = 1; |
517 | abort_on_error = 1; |
518 | add_assoc = 1; |
519 | /* follow_mounts = 0; - already is */ |
520 | matchpathcon_flags = MATCHPATHCON_VALIDATE | MATCHPATHCON_NOTRANS; |
521 | } else { |
522 | /* |
523 | * restorecon: |
524 | * No recursive descent unless -r/-R, |
525 | * Expands paths via realpath, |
526 | * Do not abort on errors during the file tree walk, |
527 | * Do not try to track inode associations for conflict detection, |
528 | * Follows mounts, |
529 | * Does lazy validation of contexts upon use. |
530 | */ |
531 | expand_realpath = 1; |
532 | follow_mounts = 1; |
533 | matchpathcon_flags = MATCHPATHCON_NOTRANS; |
534 | /* restorecon only */ |
535 | selinux_or_die(); |
536 | } |
537 | |
538 | set_matchpathcon_flags(matchpathcon_flags); |
539 | |
540 | opt_complementary = "e::vv:v--p:p--v:v--q:q--v"; |
541 | /* Option order must match OPT_x definitions! */ |
542 | if (applet_name[0] == 'r') { /* restorecon */ |
543 | flags = getopt32(argv, "de:f:ilnpqrsvo:FWR", |
544 | &exclude_dir, &input_filename, &out_filename, &verbose); |
545 | } else { /* setfiles */ |
546 | flags = getopt32(argv, "de:f:ilnpqr:svo:FW" |
547 | USE_FEATURE_SETFILES_CHECK_OPTION("c:"), |
548 | &exclude_dir, &input_filename, &rootpath, &out_filename, |
549 | USE_FEATURE_SETFILES_CHECK_OPTION(&policyfile,) |
550 | &verbose); |
551 | } |
552 | |
553 | #if ENABLE_FEATURE_SETFILES_CHECK_OPTION |
554 | if ((applet_name[0] == 's') && (flags & OPT_c)) { |
555 | FILE *policystream; |
556 | |
557 | policystream = xfopen_for_read(policyfile); |
558 | if (sepol_set_policydb_from_file(policystream) < 0) { |
559 | bb_error_msg_and_die("sepol_set_policydb_from_file on %s", policyfile); |
560 | } |
561 | fclose(policystream); |
562 | |
563 | /* Only process the specified file_contexts file, not |
564 | any .homedirs or .local files, and do not perform |
565 | context translations. */ |
566 | set_matchpathcon_flags(MATCHPATHCON_BASEONLY | |
567 | MATCHPATHCON_NOTRANS | |
568 | MATCHPATHCON_VALIDATE); |
569 | } |
570 | #endif |
571 | |
572 | while (exclude_dir) |
573 | add_exclude(llist_pop(&exclude_dir)); |
574 | |
575 | if (flags & OPT_o) { |
576 | outfile = stdout; |
577 | if (NOT_LONE_CHAR(out_filename, '-')) { |
578 | outfile = xfopen_for_write(out_filename); |
579 | } |
580 | } |
581 | if (applet_name[0] == 'r') { /* restorecon */ |
582 | if (flags & (OPT_r | OPT_R)) |
583 | recurse = 1; |
584 | } else { /* setfiles */ |
585 | if (flags & OPT_r) |
586 | rootpathlen = strlen(rootpath); |
587 | } |
588 | if (flags & OPT_s) { |
589 | input_filename = "-"; |
590 | add_assoc = 0; |
591 | } |
592 | |
593 | if (applet_name[0] == 's') { /* setfiles */ |
594 | /* Use our own invalid context checking function so that |
595 | we can support either checking against the active policy or |
596 | checking against a binary policy file. */ |
597 | set_matchpathcon_canoncon(&canoncon); |
598 | if (argc == 1) |
599 | bb_show_usage(); |
600 | if (stat(argv[optind], &sb) < 0) { |
601 | bb_simple_perror_msg_and_die(argv[optind]); |
602 | } |
603 | if (!S_ISREG(sb.st_mode)) { |
604 | bb_error_msg_and_die("spec file %s is not a regular file", argv[optind]); |
605 | } |
606 | /* Load the file contexts configuration and check it. */ |
607 | rc = matchpathcon_init(argv[optind]); |
608 | if (rc < 0) { |
609 | bb_simple_perror_msg_and_die(argv[optind]); |
610 | } |
611 | |
612 | optind++; |
613 | |
614 | if (nerr) |
615 | exit(EXIT_FAILURE); |
616 | } |
617 | |
618 | if (input_filename) { |
619 | ssize_t len; |
620 | FILE *f = stdin; |
621 | |
622 | if (NOT_LONE_CHAR(input_filename, '-')) |
623 | f = xfopen_for_read(input_filename); |
624 | while ((len = getline(&buf, &buf_len, f)) > 0) { |
625 | buf[len - 1] = '\0'; |
626 | errors |= process_one(buf); |
627 | } |
628 | if (ENABLE_FEATURE_CLEAN_UP) |
629 | fclose_if_not_stdin(f); |
630 | } else { |
631 | if (optind >= argc) |
632 | bb_show_usage(); |
633 | for (i = optind; i < argc; i++) { |
634 | errors |= process_one(argv[i]); |
635 | } |
636 | } |
637 | |
638 | if (FLAG_W_warn_no_match) |
639 | matchpathcon_checkmatches(argv[0]); |
640 | |
641 | if (ENABLE_FEATURE_CLEAN_UP && outfile) |
642 | fclose(outfile); |
643 | |
644 | return errors; |
645 | } |