]>
Commit | Line | Data |
---|---|---|
1 | /* SPDX-License-Identifier: LGPL-2.1-or-later */ | |
2 | /*** | |
3 | Copyright © 2013 Intel Corporation | |
4 | Authors: | |
5 | Nathaniel Chen <nathaniel.chen@intel.com> | |
6 | ***/ | |
7 | ||
8 | #include <fcntl.h> | |
9 | #include <stdio.h> | |
10 | #include <unistd.h> | |
11 | ||
12 | #include "sd-messages.h" | |
13 | ||
14 | #include "alloc-util.h" | |
15 | #include "dirent-util.h" | |
16 | #include "errno-util.h" | |
17 | #include "fd-util.h" | |
18 | #include "fileio.h" | |
19 | #include "log.h" | |
20 | #include "smack-setup.h" | |
21 | #include "string-util.h" | |
22 | ||
23 | #if ENABLE_SMACK | |
24 | ||
25 | static int fdopen_unlocked_at(int dfd, const char *dir, const char *name, int *status, FILE **ret_file) { | |
26 | int fd, r; | |
27 | FILE *f; | |
28 | ||
29 | fd = openat(dfd, name, O_RDONLY|O_CLOEXEC); | |
30 | if (fd < 0) { | |
31 | if (*status == 0) | |
32 | *status = -errno; | |
33 | ||
34 | return log_warning_errno(errno, "Failed to open \"%s/%s\": %m", dir, name); | |
35 | } | |
36 | ||
37 | r = fdopen_unlocked(fd, "r", &f); | |
38 | if (r < 0) { | |
39 | if (*status == 0) | |
40 | *status = r; | |
41 | ||
42 | safe_close(fd); | |
43 | return log_error_errno(r, "Failed to open \"%s/%s\": %m", dir, name); | |
44 | } | |
45 | ||
46 | *ret_file = f; | |
47 | return 0; | |
48 | } | |
49 | ||
50 | static int write_access2_rules(const char *srcdir) { | |
51 | _cleanup_close_ int load2_fd = -EBADF, change_fd = -EBADF; | |
52 | _cleanup_closedir_ DIR *dir = NULL; | |
53 | int dfd, r; | |
54 | ||
55 | load2_fd = r = RET_NERRNO(open("/sys/fs/smackfs/load2", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY)); | |
56 | if (r < 0) { | |
57 | if (r != -ENOENT) | |
58 | log_warning_errno(r, "Failed to open %s: %m", "/sys/fs/smackfs/load2"); | |
59 | return r; | |
60 | } | |
61 | ||
62 | change_fd = r = RET_NERRNO(open("/sys/fs/smackfs/change-rule", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY)); | |
63 | if (r < 0) { | |
64 | if (r != -ENOENT) | |
65 | log_warning_errno(r, "Failed to open %s: %m", "/sys/fs/smackfs/change-rule"); | |
66 | return r; | |
67 | } | |
68 | ||
69 | /* write rules to load2 or change-rule from every file in the directory */ | |
70 | dir = opendir(srcdir); | |
71 | if (!dir) { | |
72 | if (errno != ENOENT) | |
73 | log_warning_errno(errno, "Failed to open %s/: %m", srcdir); | |
74 | return errno; /* positive on purpose */ | |
75 | } | |
76 | ||
77 | dfd = dirfd(dir); | |
78 | assert(dfd >= 0); | |
79 | ||
80 | r = 0; | |
81 | FOREACH_DIRENT(entry, dir, return 0) { | |
82 | _cleanup_fclose_ FILE *policy = NULL; | |
83 | ||
84 | if (!dirent_is_file(entry)) | |
85 | continue; | |
86 | ||
87 | if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0) | |
88 | continue; | |
89 | ||
90 | /* load2 write rules in the kernel require a line buffered stream */ | |
91 | for (;;) { | |
92 | _cleanup_free_ char *buf = NULL, *sbj = NULL, *obj = NULL, *acc1 = NULL, *acc2 = NULL; | |
93 | int q; | |
94 | ||
95 | q = read_line(policy, NAME_MAX, &buf); | |
96 | if (q < 0) | |
97 | return log_error_errno(q, "%s/%s: failed to read line: %m", srcdir, entry->d_name); | |
98 | if (q == 0) | |
99 | break; | |
100 | ||
101 | if (isempty(buf) || strchr(COMMENTS, buf[0])) | |
102 | continue; | |
103 | ||
104 | /* if 3 args -> load rule : subject object access1 */ | |
105 | /* if 4 args -> change rule : subject object access1 access2 */ | |
106 | if (sscanf(buf, "%ms %ms %ms %ms", &sbj, &obj, &acc1, &acc2) < 3) { | |
107 | log_error_errno(errno, "%s/%s: failed to parse rule '%s', ignoring.", | |
108 | srcdir, entry->d_name, buf); | |
109 | continue; | |
110 | } | |
111 | ||
112 | q = RET_NERRNO(write(isempty(acc2) ? load2_fd : change_fd, buf, strlen(buf))); | |
113 | if (q < 0) { | |
114 | log_error_errno(q, "%s/%s: failed to write '%s' to '%s': %m", | |
115 | srcdir, entry->d_name, | |
116 | buf, isempty(acc2) ? "/sys/fs/smackfs/load2" : "/sys/fs/smackfs/change-rule"); | |
117 | RET_GATHER(r, q); | |
118 | } | |
119 | } | |
120 | } | |
121 | ||
122 | return r; | |
123 | } | |
124 | ||
125 | static int write_cipso2_rules(const char *srcdir) { | |
126 | _cleanup_close_ int cipso2_fd = -EBADF; | |
127 | _cleanup_closedir_ DIR *dir = NULL; | |
128 | int dfd, r; | |
129 | ||
130 | cipso2_fd = r = RET_NERRNO(open("/sys/fs/smackfs/cipso2", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY)); | |
131 | if (r < 0) { | |
132 | if (r != -ENOENT) | |
133 | log_warning_errno(r, "Failed to open %s: %m", "/sys/fs/smackfs/cipso2"); | |
134 | return r; | |
135 | } | |
136 | ||
137 | /* write rules to cipso2 from every file in the directory */ | |
138 | dir = opendir(srcdir); | |
139 | if (!dir) { | |
140 | if (errno != ENOENT) | |
141 | log_warning_errno(errno, "Failed to open %s/: %m", srcdir); | |
142 | return errno; /* positive on purpose */ | |
143 | } | |
144 | ||
145 | dfd = dirfd(dir); | |
146 | assert(dfd >= 0); | |
147 | ||
148 | r = 0; | |
149 | FOREACH_DIRENT(entry, dir, return 0) { | |
150 | _cleanup_fclose_ FILE *policy = NULL; | |
151 | ||
152 | if (!dirent_is_file(entry)) | |
153 | continue; | |
154 | ||
155 | if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0) | |
156 | continue; | |
157 | ||
158 | /* cipso2 write rules in the kernel require a line buffered stream */ | |
159 | for (;;) { | |
160 | _cleanup_free_ char *buf = NULL; | |
161 | int q; | |
162 | ||
163 | q = read_line(policy, NAME_MAX, &buf); | |
164 | if (q < 0) | |
165 | return log_error_errno(q, "%s/%s: failed to read line: %m", | |
166 | srcdir, entry->d_name); | |
167 | if (q == 0) | |
168 | break; | |
169 | ||
170 | if (isempty(buf) || strchr(COMMENTS, buf[0])) | |
171 | continue; | |
172 | ||
173 | q = RET_NERRNO(write(cipso2_fd, buf, strlen(buf))); | |
174 | if (q < 0) { | |
175 | log_error_errno(q, "%s/%s: failed to write '%s' to %s: %m", | |
176 | srcdir, entry->d_name, | |
177 | buf, "/sys/fs/smackfs/cipso2"); | |
178 | RET_GATHER(r, q); | |
179 | break; | |
180 | } | |
181 | } | |
182 | } | |
183 | ||
184 | return r; | |
185 | } | |
186 | ||
187 | static int write_netlabel_rules(const char *srcdir) { | |
188 | _cleanup_fclose_ FILE *dst = NULL; | |
189 | _cleanup_closedir_ DIR *dir = NULL; | |
190 | int dfd, r; | |
191 | ||
192 | dst = fopen("/sys/fs/smackfs/netlabel", "we"); | |
193 | if (!dst) { | |
194 | if (errno != ENOENT) | |
195 | log_warning_errno(errno, "Failed to open %s/: %m", "/sys/fs/smackfs/netlabel"); | |
196 | return -errno; /* negative error */ | |
197 | } | |
198 | ||
199 | /* write rules to dst from every file in the directory */ | |
200 | dir = opendir(srcdir); | |
201 | if (!dir) { | |
202 | if (errno != ENOENT) | |
203 | log_warning_errno(errno, "Failed to open %s/: %m", srcdir); | |
204 | return errno; /* positive on purpose */ | |
205 | } | |
206 | ||
207 | dfd = dirfd(dir); | |
208 | assert(dfd >= 0); | |
209 | ||
210 | r = 0; | |
211 | FOREACH_DIRENT(entry, dir, return 0) { | |
212 | _cleanup_fclose_ FILE *policy = NULL; | |
213 | ||
214 | if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0) | |
215 | continue; | |
216 | ||
217 | /* load2 write rules in the kernel require a line buffered stream */ | |
218 | for (;;) { | |
219 | _cleanup_free_ char *buf = NULL; | |
220 | int q; | |
221 | ||
222 | q = read_line(policy, NAME_MAX, &buf); | |
223 | if (q < 0) | |
224 | return log_error_errno(q, "%s/%s: failed to read line: %m", | |
225 | srcdir, entry->d_name); | |
226 | if (q == 0) | |
227 | break; | |
228 | ||
229 | if (!fputs(buf, dst)) { | |
230 | log_error_errno(errno, "Failed to write line to %s: %m", "/sys/fs/smackfs/netlabel"); | |
231 | RET_GATHER(r, -errno); | |
232 | break; | |
233 | } | |
234 | q = fflush_and_check(dst); | |
235 | if (q < 0) { | |
236 | log_error_errno(q, "Failed to flush %s: %m", "/sys/fs/smackfs/netlabel"); | |
237 | RET_GATHER(r, q); | |
238 | break; | |
239 | } | |
240 | } | |
241 | } | |
242 | ||
243 | return r; | |
244 | } | |
245 | ||
246 | static int write_onlycap_list(void) { | |
247 | _cleanup_close_ int onlycap_fd = -EBADF; | |
248 | _cleanup_free_ char *list = NULL; | |
249 | _cleanup_fclose_ FILE *f = NULL; | |
250 | size_t len = 0; | |
251 | int r; | |
252 | ||
253 | f = fopen("/etc/smack/onlycap", "re"); | |
254 | if (!f) { | |
255 | if (errno != ENOENT) | |
256 | log_warning_errno(errno, "Failed to open %s: %m", "/etc/smack/onlycap"); | |
257 | ||
258 | return errno == ENOENT ? ENOENT : -errno; | |
259 | } | |
260 | ||
261 | for (;;) { | |
262 | _cleanup_free_ char *buf = NULL; | |
263 | size_t l; | |
264 | ||
265 | r = read_line(f, LONG_LINE_MAX, &buf); | |
266 | if (r < 0) | |
267 | return log_error_errno(r, "%s: failed to read line: %m", "/etc/smack/onlycap"); | |
268 | if (r == 0) | |
269 | break; | |
270 | ||
271 | if (isempty(buf) || strchr(COMMENTS, *buf)) | |
272 | continue; | |
273 | ||
274 | l = strlen(buf); | |
275 | if (!GREEDY_REALLOC(list, len + l + 1)) | |
276 | return log_oom(); | |
277 | ||
278 | stpcpy(list + len, buf)[0] = ' '; | |
279 | len += l + 1; | |
280 | } | |
281 | ||
282 | if (len == 0) | |
283 | return 0; | |
284 | ||
285 | list[len - 1] = 0; | |
286 | ||
287 | onlycap_fd = r = RET_NERRNO(open("/sys/fs/smackfs/onlycap", O_WRONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY)); | |
288 | if (r < 0) { | |
289 | if (r != -ENOENT) | |
290 | log_warning_errno(r, "Failed to open %s: %m", "/sys/fs/smackfs/onlycap"); | |
291 | return r; | |
292 | } | |
293 | ||
294 | r = RET_NERRNO(write(onlycap_fd, list, len)); | |
295 | if (r < 0) | |
296 | return log_error_errno(r, "%s: failed to write onlycap list(%s): %m", | |
297 | "/sys/fs/smackfs/onlycap", list); | |
298 | ||
299 | return 0; | |
300 | } | |
301 | ||
302 | #endif | |
303 | ||
304 | int mac_smack_setup(bool *loaded_policy) { | |
305 | ||
306 | #if ENABLE_SMACK | |
307 | int r; | |
308 | ||
309 | assert(loaded_policy); | |
310 | ||
311 | r = write_access2_rules("/etc/smack/accesses.d"); | |
312 | switch (r) { | |
313 | case -ENOENT: | |
314 | log_debug("Smack is not enabled in the kernel."); | |
315 | return 0; | |
316 | case ENOENT: | |
317 | log_debug("Smack access rules directory '/etc/smack/accesses.d/' not found"); | |
318 | return 0; | |
319 | case 0: | |
320 | log_info("Successfully loaded Smack policies."); | |
321 | break; | |
322 | default: | |
323 | log_warning_errno(r, "Failed to load Smack access rules, ignoring: %m"); | |
324 | return 0; | |
325 | } | |
326 | ||
327 | #if HAVE_SMACK_RUN_LABEL | |
328 | r = write_string_file("/proc/self/attr/current", SMACK_RUN_LABEL, WRITE_STRING_FILE_DISABLE_BUFFER); | |
329 | if (r < 0) | |
330 | log_warning_errno(r, "Failed to set SMACK label \"" SMACK_RUN_LABEL "\" on self: %m"); | |
331 | r = write_string_file("/sys/fs/smackfs/ambient", SMACK_RUN_LABEL, WRITE_STRING_FILE_DISABLE_BUFFER); | |
332 | if (r < 0) | |
333 | log_warning_errno(r, "Failed to set SMACK ambient label \"" SMACK_RUN_LABEL "\": %m"); | |
334 | r = write_string_file("/sys/fs/smackfs/netlabel", | |
335 | "0.0.0.0/0 " SMACK_RUN_LABEL, WRITE_STRING_FILE_DISABLE_BUFFER); | |
336 | if (r < 0) | |
337 | log_warning_errno(r, "Failed to set SMACK netlabel rule \"0.0.0.0/0 " SMACK_RUN_LABEL "\": %m"); | |
338 | r = write_string_file("/sys/fs/smackfs/netlabel", "127.0.0.1 -CIPSO", WRITE_STRING_FILE_DISABLE_BUFFER); | |
339 | if (r < 0) | |
340 | log_warning_errno(r, "Failed to set SMACK netlabel rule \"127.0.0.1 -CIPSO\": %m"); | |
341 | #endif | |
342 | ||
343 | r = write_cipso2_rules("/etc/smack/cipso.d"); | |
344 | switch (r) { | |
345 | case -ENOENT: | |
346 | log_debug("Smack/CIPSO is not enabled in the kernel."); | |
347 | return 0; | |
348 | case ENOENT: | |
349 | log_debug("Smack/CIPSO access rules directory '/etc/smack/cipso.d/' not found"); | |
350 | break; | |
351 | case 0: | |
352 | log_info("Successfully loaded Smack/CIPSO policies."); | |
353 | break; | |
354 | default: | |
355 | log_warning_errno(r, "Failed to load Smack/CIPSO access rules, ignoring: %m"); | |
356 | } | |
357 | ||
358 | r = write_netlabel_rules("/etc/smack/netlabel.d"); | |
359 | switch (r) { | |
360 | case -ENOENT: | |
361 | log_debug("Smack/CIPSO is not enabled in the kernel."); | |
362 | return 0; | |
363 | case ENOENT: | |
364 | log_debug("Smack network host rules directory '/etc/smack/netlabel.d/' not found"); | |
365 | break; | |
366 | case 0: | |
367 | log_info("Successfully loaded Smack network host rules."); | |
368 | break; | |
369 | default: | |
370 | log_warning_errno(r, "Failed to load Smack network host rules: %m, ignoring."); | |
371 | } | |
372 | ||
373 | r = write_onlycap_list(); | |
374 | switch (r) { | |
375 | case -ENOENT: | |
376 | log_debug("Smack is not enabled in the kernel."); | |
377 | break; | |
378 | case ENOENT: | |
379 | log_debug("Smack onlycap list file '/etc/smack/onlycap' not found"); | |
380 | break; | |
381 | case 0: | |
382 | log_info("Successfully wrote Smack onlycap list."); | |
383 | break; | |
384 | default: | |
385 | return log_struct_errno(LOG_EMERG, r, | |
386 | LOG_MESSAGE("Failed to write Smack onlycap list: %m"), | |
387 | LOG_MESSAGE_ID(SD_MESSAGE_SMACK_FAILED_WRITE_STR)); | |
388 | } | |
389 | ||
390 | *loaded_policy = true; | |
391 | ||
392 | #endif | |
393 | ||
394 | return 0; | |
395 | } |