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1 | /* SPDX-License-Identifier: LGPL-2.1-or-later */ | |
2 | ||
3 | #if HAVE_VALGRIND_MEMCHECK_H | |
4 | #include <valgrind/memcheck.h> | |
5 | #endif | |
6 | ||
7 | #include <linux/dm-ioctl.h> | |
8 | #include <linux/loop.h> | |
9 | #include <sys/file.h> | |
10 | #include <sys/mount.h> | |
11 | #include <sys/prctl.h> | |
12 | #include <sys/wait.h> | |
13 | #include <sysexits.h> | |
14 | ||
15 | #if HAVE_OPENSSL | |
16 | #include <openssl/err.h> | |
17 | #include <openssl/pem.h> | |
18 | #include <openssl/x509.h> | |
19 | #endif | |
20 | ||
21 | #include "sd-device.h" | |
22 | #include "sd-id128.h" | |
23 | ||
24 | #include "architecture.h" | |
25 | #include "ask-password-api.h" | |
26 | #include "blkid-util.h" | |
27 | #include "blockdev-util.h" | |
28 | #include "btrfs-util.h" | |
29 | #include "chase.h" | |
30 | #include "conf-files.h" | |
31 | #include "constants.h" | |
32 | #include "copy.h" | |
33 | #include "cryptsetup-util.h" | |
34 | #include "device-nodes.h" | |
35 | #include "device-util.h" | |
36 | #include "devnum-util.h" | |
37 | #include "discover-image.h" | |
38 | #include "dissect-image.h" | |
39 | #include "dm-util.h" | |
40 | #include "env-file.h" | |
41 | #include "env-util.h" | |
42 | #include "extension-util.h" | |
43 | #include "fd-util.h" | |
44 | #include "fileio.h" | |
45 | #include "fs-util.h" | |
46 | #include "fsck-util.h" | |
47 | #include "gpt.h" | |
48 | #include "hexdecoct.h" | |
49 | #include "hostname-setup.h" | |
50 | #include "id128-util.h" | |
51 | #include "import-util.h" | |
52 | #include "io-util.h" | |
53 | #include "missing_mount.h" | |
54 | #include "missing_syscall.h" | |
55 | #include "mkdir-label.h" | |
56 | #include "mount-util.h" | |
57 | #include "mountpoint-util.h" | |
58 | #include "namespace-util.h" | |
59 | #include "nulstr-util.h" | |
60 | #include "openssl-util.h" | |
61 | #include "os-util.h" | |
62 | #include "path-util.h" | |
63 | #include "proc-cmdline.h" | |
64 | #include "process-util.h" | |
65 | #include "raw-clone.h" | |
66 | #include "resize-fs.h" | |
67 | #include "signal-util.h" | |
68 | #include "sparse-endian.h" | |
69 | #include "stat-util.h" | |
70 | #include "stdio-util.h" | |
71 | #include "string-table.h" | |
72 | #include "string-util.h" | |
73 | #include "strv.h" | |
74 | #include "tmpfile-util.h" | |
75 | #include "udev-util.h" | |
76 | #include "user-util.h" | |
77 | #include "xattr-util.h" | |
78 | ||
79 | /* how many times to wait for the device nodes to appear */ | |
80 | #define N_DEVICE_NODE_LIST_ATTEMPTS 10 | |
81 | ||
82 | int dissect_fstype_ok(const char *fstype) { | |
83 | const char *e; | |
84 | bool b; | |
85 | ||
86 | /* When we automatically mount file systems, be a bit conservative by default what we are willing to | |
87 | * mount, just as an extra safety net to not mount with badly maintained legacy file system | |
88 | * drivers. */ | |
89 | ||
90 | e = secure_getenv("SYSTEMD_DISSECT_FILE_SYSTEMS"); | |
91 | if (e) { | |
92 | _cleanup_strv_free_ char **l = NULL; | |
93 | ||
94 | l = strv_split(e, ":"); | |
95 | if (!l) | |
96 | return -ENOMEM; | |
97 | ||
98 | b = strv_contains(l, fstype); | |
99 | } else | |
100 | b = STR_IN_SET(fstype, | |
101 | "btrfs", | |
102 | "erofs", | |
103 | "ext4", | |
104 | "f2fs", | |
105 | "squashfs", | |
106 | "vfat", | |
107 | "xfs"); | |
108 | if (b) | |
109 | return true; | |
110 | ||
111 | log_debug("File system type '%s' is not allowed to be mounted as result of automatic dissection.", fstype); | |
112 | return false; | |
113 | } | |
114 | ||
115 | int probe_sector_size(int fd, uint32_t *ret) { | |
116 | ||
117 | /* Disk images might be for 512B or for 4096 sector sizes, let's try to auto-detect that by searching | |
118 | * for the GPT headers at the relevant byte offsets */ | |
119 | ||
120 | assert_cc(sizeof(GptHeader) == 92); | |
121 | ||
122 | /* We expect a sector size in the range 512…4096. The GPT header is located in the second | |
123 | * sector. Hence it could be at byte 512 at the earliest, and at byte 4096 at the latest. And we must | |
124 | * read with granularity of the largest sector size we care about. Which means 8K. */ | |
125 | uint8_t sectors[2 * 4096]; | |
126 | uint32_t found = 0; | |
127 | ssize_t n; | |
128 | ||
129 | assert(fd >= 0); | |
130 | assert(ret); | |
131 | ||
132 | n = pread(fd, sectors, sizeof(sectors), 0); | |
133 | if (n < 0) | |
134 | return -errno; | |
135 | if (n != sizeof(sectors)) /* too short? */ | |
136 | goto not_found; | |
137 | ||
138 | /* Let's see if we find the GPT partition header with various expected sector sizes */ | |
139 | for (uint32_t sz = 512; sz <= 4096; sz <<= 1) { | |
140 | const GptHeader *p; | |
141 | ||
142 | assert(sizeof(sectors) >= sz * 2); | |
143 | p = (const GptHeader*) (sectors + sz); | |
144 | ||
145 | if (!gpt_header_has_signature(p)) | |
146 | continue; | |
147 | ||
148 | if (found != 0) | |
149 | return log_debug_errno(SYNTHETIC_ERRNO(ENOTUNIQ), | |
150 | "Detected valid partition table at offsets matching multiple sector sizes, refusing."); | |
151 | ||
152 | found = sz; | |
153 | } | |
154 | ||
155 | if (found != 0) { | |
156 | log_debug("Determined sector size %" PRIu32 " based on discovered partition table.", found); | |
157 | *ret = found; | |
158 | return 1; /* indicate we *did* find it */ | |
159 | } | |
160 | ||
161 | not_found: | |
162 | log_debug("Couldn't find any partition table to derive sector size of."); | |
163 | *ret = 512; /* pick the traditional default */ | |
164 | return 0; /* indicate we didn't find it */ | |
165 | } | |
166 | ||
167 | int probe_sector_size_prefer_ioctl(int fd, uint32_t *ret) { | |
168 | struct stat st; | |
169 | ||
170 | assert(fd >= 0); | |
171 | assert(ret); | |
172 | ||
173 | /* Just like probe_sector_size(), but if we are looking at a block device, will use the already | |
174 | * configured sector size rather than probing by contents */ | |
175 | ||
176 | if (fstat(fd, &st) < 0) | |
177 | return -errno; | |
178 | ||
179 | if (S_ISBLK(st.st_mode)) | |
180 | return blockdev_get_sector_size(fd, ret); | |
181 | ||
182 | return probe_sector_size(fd, ret); | |
183 | } | |
184 | ||
185 | int probe_filesystem_full( | |
186 | int fd, | |
187 | const char *path, | |
188 | uint64_t offset, | |
189 | uint64_t size, | |
190 | char **ret_fstype) { | |
191 | ||
192 | /* Try to find device content type and return it in *ret_fstype. If nothing is found, | |
193 | * 0/NULL will be returned. -EUCLEAN will be returned for ambiguous results, and a | |
194 | * different error otherwise. */ | |
195 | ||
196 | #if HAVE_BLKID | |
197 | _cleanup_(blkid_free_probep) blkid_probe b = NULL; | |
198 | _cleanup_free_ char *path_by_fd = NULL; | |
199 | _cleanup_close_ int fd_close = -EBADF; | |
200 | const char *fstype; | |
201 | int r; | |
202 | ||
203 | assert(fd >= 0 || path); | |
204 | assert(ret_fstype); | |
205 | ||
206 | if (fd < 0) { | |
207 | fd_close = open(path, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); | |
208 | if (fd_close < 0) | |
209 | return -errno; | |
210 | ||
211 | fd = fd_close; | |
212 | } | |
213 | ||
214 | if (!path) { | |
215 | r = fd_get_path(fd, &path_by_fd); | |
216 | if (r < 0) | |
217 | return r; | |
218 | ||
219 | path = path_by_fd; | |
220 | } | |
221 | ||
222 | if (size == 0) /* empty size? nothing found! */ | |
223 | goto not_found; | |
224 | ||
225 | b = blkid_new_probe(); | |
226 | if (!b) | |
227 | return -ENOMEM; | |
228 | ||
229 | /* The Linux kernel maintains separate block device caches for main ("whole") and partition block | |
230 | * devices, which means making a change to one might not be reflected immediately when reading via | |
231 | * the other. That's massively confusing when mixing accesses to such devices. Let's address this in | |
232 | * a limited way: when probing a file system that is not at the beginning of the block device we | |
233 | * apparently probe a partition via the main block device, and in that case let's first flush the | |
234 | * main block device cache, so that we get the data that the per-partition block device last | |
235 | * sync'ed on. | |
236 | * | |
237 | * This only works under the assumption that any tools that write to the partition block devices | |
238 | * issue an syncfs()/fsync() on the device after making changes. Typically file system formatting | |
239 | * tools that write a superblock onto a partition block device do that, however. */ | |
240 | if (offset != 0) | |
241 | if (ioctl(fd, BLKFLSBUF, 0) < 0) | |
242 | log_debug_errno(errno, "Failed to flush block device cache, ignoring: %m"); | |
243 | ||
244 | errno = 0; | |
245 | r = blkid_probe_set_device( | |
246 | b, | |
247 | fd, | |
248 | offset, | |
249 | size == UINT64_MAX ? 0 : size); /* when blkid sees size=0 it understands "everything". We prefer using UINT64_MAX for that */ | |
250 | if (r != 0) | |
251 | return errno_or_else(ENOMEM); | |
252 | ||
253 | blkid_probe_enable_superblocks(b, 1); | |
254 | blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE); | |
255 | ||
256 | errno = 0; | |
257 | r = blkid_do_safeprobe(b); | |
258 | if (r == _BLKID_SAFEPROBE_NOT_FOUND) | |
259 | goto not_found; | |
260 | if (r == _BLKID_SAFEPROBE_AMBIGUOUS) | |
261 | return log_debug_errno(SYNTHETIC_ERRNO(EUCLEAN), | |
262 | "Results ambiguous for partition %s", path); | |
263 | if (r == _BLKID_SAFEPROBE_ERROR) | |
264 | return log_debug_errno(errno_or_else(EIO), "Failed to probe partition %s: %m", path); | |
265 | ||
266 | assert(r == _BLKID_SAFEPROBE_FOUND); | |
267 | ||
268 | (void) blkid_probe_lookup_value(b, "TYPE", &fstype, NULL); | |
269 | ||
270 | if (fstype) { | |
271 | log_debug("Probed fstype '%s' on partition %s.", fstype, path); | |
272 | return strdup_to_full(ret_fstype, fstype); | |
273 | } | |
274 | ||
275 | not_found: | |
276 | log_debug("No type detected on partition %s", path); | |
277 | *ret_fstype = NULL; | |
278 | return 0; | |
279 | #else | |
280 | return -EOPNOTSUPP; | |
281 | #endif | |
282 | } | |
283 | ||
284 | #if HAVE_BLKID | |
285 | static int image_policy_may_use( | |
286 | const ImagePolicy *policy, | |
287 | PartitionDesignator designator) { | |
288 | ||
289 | PartitionPolicyFlags f; | |
290 | ||
291 | /* For each partition we find in the partition table do a first check if it may exist at all given | |
292 | * the policy, or if it shall be ignored. */ | |
293 | ||
294 | f = image_policy_get_exhaustively(policy, designator); | |
295 | if (f < 0) | |
296 | return f; | |
297 | ||
298 | if ((f & _PARTITION_POLICY_USE_MASK) == PARTITION_POLICY_ABSENT) | |
299 | /* only flag set in policy is "absent"? then this partition may not exist at all */ | |
300 | return log_debug_errno( | |
301 | SYNTHETIC_ERRNO(ERFKILL), | |
302 | "Partition of designator '%s' exists, but not allowed by policy, refusing.", | |
303 | partition_designator_to_string(designator)); | |
304 | if ((f & _PARTITION_POLICY_USE_MASK & ~PARTITION_POLICY_ABSENT) == PARTITION_POLICY_UNUSED) { | |
305 | /* only "unused" or "unused" + "absent" are set? then don't use it */ | |
306 | log_debug("Partition of designator '%s' exists, and policy dictates to ignore it, doing so.", | |
307 | partition_designator_to_string(designator)); | |
308 | return false; /* ignore! */ | |
309 | } | |
310 | ||
311 | return true; /* use! */ | |
312 | } | |
313 | ||
314 | static int image_policy_check_protection( | |
315 | const ImagePolicy *policy, | |
316 | PartitionDesignator designator, | |
317 | PartitionPolicyFlags found_flags) { | |
318 | ||
319 | PartitionPolicyFlags policy_flags; | |
320 | ||
321 | /* Checks if the flags in the policy for the designated partition overlap the flags of what we found */ | |
322 | ||
323 | if (found_flags < 0) | |
324 | return found_flags; | |
325 | ||
326 | policy_flags = image_policy_get_exhaustively(policy, designator); | |
327 | if (policy_flags < 0) | |
328 | return policy_flags; | |
329 | ||
330 | if ((found_flags & policy_flags) == 0) { | |
331 | _cleanup_free_ char *found_flags_string = NULL, *policy_flags_string = NULL; | |
332 | ||
333 | (void) partition_policy_flags_to_string(found_flags, /* simplify= */ true, &found_flags_string); | |
334 | (void) partition_policy_flags_to_string(policy_flags, /* simplify= */ true, &policy_flags_string); | |
335 | ||
336 | return log_debug_errno(SYNTHETIC_ERRNO(ERFKILL), "Partition %s discovered with policy '%s' but '%s' was required, refusing.", | |
337 | partition_designator_to_string(designator), | |
338 | strnull(found_flags_string), strnull(policy_flags_string)); | |
339 | } | |
340 | ||
341 | return 0; | |
342 | } | |
343 | ||
344 | static int image_policy_check_partition_flags( | |
345 | const ImagePolicy *policy, | |
346 | PartitionDesignator designator, | |
347 | uint64_t gpt_flags) { | |
348 | ||
349 | PartitionPolicyFlags policy_flags; | |
350 | bool b; | |
351 | ||
352 | /* Checks if the partition flags in the policy match reality */ | |
353 | ||
354 | policy_flags = image_policy_get_exhaustively(policy, designator); | |
355 | if (policy_flags < 0) | |
356 | return policy_flags; | |
357 | ||
358 | b = FLAGS_SET(gpt_flags, SD_GPT_FLAG_READ_ONLY); | |
359 | if ((policy_flags & _PARTITION_POLICY_READ_ONLY_MASK) == (b ? PARTITION_POLICY_READ_ONLY_OFF : PARTITION_POLICY_READ_ONLY_ON)) | |
360 | return log_debug_errno(SYNTHETIC_ERRNO(ERFKILL), "Partition %s has 'read-only' flag incorrectly set (must be %s, is %s), refusing.", | |
361 | partition_designator_to_string(designator), | |
362 | one_zero(!b), one_zero(b)); | |
363 | ||
364 | b = FLAGS_SET(gpt_flags, SD_GPT_FLAG_GROWFS); | |
365 | if ((policy_flags & _PARTITION_POLICY_GROWFS_MASK) == (b ? PARTITION_POLICY_GROWFS_OFF : PARTITION_POLICY_GROWFS_ON)) | |
366 | return log_debug_errno(SYNTHETIC_ERRNO(ERFKILL), "Partition %s has 'growfs' flag incorrectly set (must be %s, is %s), refusing.", | |
367 | partition_designator_to_string(designator), | |
368 | one_zero(!b), one_zero(b)); | |
369 | ||
370 | return 0; | |
371 | } | |
372 | ||
373 | static int dissected_image_probe_filesystems( | |
374 | DissectedImage *m, | |
375 | int fd, | |
376 | const ImagePolicy *policy) { | |
377 | ||
378 | int r; | |
379 | ||
380 | assert(m); | |
381 | ||
382 | /* Fill in file system types if we don't know them yet. */ | |
383 | ||
384 | for (PartitionDesignator i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) { | |
385 | DissectedPartition *p = m->partitions + i; | |
386 | PartitionPolicyFlags found_flags; | |
387 | ||
388 | if (!p->found) | |
389 | continue; | |
390 | ||
391 | if (!p->fstype) { | |
392 | /* If we have an fd referring to the partition block device, use that. Otherwise go | |
393 | * via the whole block device or backing regular file, and read via offset. */ | |
394 | if (p->mount_node_fd >= 0) | |
395 | r = probe_filesystem_full(p->mount_node_fd, p->node, 0, UINT64_MAX, &p->fstype); | |
396 | else | |
397 | r = probe_filesystem_full(fd, p->node, p->offset, p->size, &p->fstype); | |
398 | if (r < 0) | |
399 | return r; | |
400 | } | |
401 | ||
402 | if (streq_ptr(p->fstype, "crypto_LUKS")) { | |
403 | m->encrypted = true; | |
404 | found_flags = PARTITION_POLICY_ENCRYPTED; /* found this one, and its definitely encrypted */ | |
405 | } else | |
406 | /* found it, but it's definitely not encrypted, hence mask the encrypted flag, but | |
407 | * set all other ways that indicate "present". */ | |
408 | found_flags = PARTITION_POLICY_UNPROTECTED|PARTITION_POLICY_VERITY|PARTITION_POLICY_SIGNED; | |
409 | ||
410 | if (p->fstype && fstype_is_ro(p->fstype)) | |
411 | p->rw = false; | |
412 | ||
413 | if (!p->rw) | |
414 | p->growfs = false; | |
415 | ||
416 | /* We might have learnt more about the file system now (i.e. whether it is encrypted or not), | |
417 | * hence we need to validate this against policy again, to see if the policy still matches | |
418 | * with this new information. Note that image_policy_check_protection() will check for | |
419 | * overlap between what's allowed in the policy and what we pass as 'found_policy' here. In | |
420 | * the unencrypted case we thus might pass an overly unspecific mask here (i.e. unprotected | |
421 | * OR verity OR signed), but that's fine since the earlier policy check already checked more | |
422 | * specific which of those three cases where OK. Keep in mind that this function here only | |
423 | * looks at specific partitions (and thus can only deduce encryption or not) but not the | |
424 | * overall partition table (and thus cannot deduce verity or not). The earlier dissection | |
425 | * checks already did the relevant checks that look at the whole partition table, and | |
426 | * enforced policy there as needed. */ | |
427 | r = image_policy_check_protection(policy, i, found_flags); | |
428 | if (r < 0) | |
429 | return r; | |
430 | } | |
431 | ||
432 | return 0; | |
433 | } | |
434 | ||
435 | static void check_partition_flags( | |
436 | const char *node, | |
437 | unsigned long long pflags, | |
438 | unsigned long long supported) { | |
439 | ||
440 | assert(node); | |
441 | ||
442 | /* Mask away all flags supported by this partition's type and the three flags the UEFI spec defines generically */ | |
443 | pflags &= ~(supported | | |
444 | SD_GPT_FLAG_REQUIRED_PARTITION | | |
445 | SD_GPT_FLAG_NO_BLOCK_IO_PROTOCOL | | |
446 | SD_GPT_FLAG_LEGACY_BIOS_BOOTABLE); | |
447 | ||
448 | if (pflags == 0) | |
449 | return; | |
450 | ||
451 | /* If there are other bits set, then log about it, to make things discoverable */ | |
452 | for (unsigned i = 0; i < sizeof(pflags) * 8; i++) { | |
453 | unsigned long long bit = 1ULL << i; | |
454 | if (!FLAGS_SET(pflags, bit)) | |
455 | continue; | |
456 | ||
457 | log_debug("Unexpected partition flag %llu set on %s!", bit, node); | |
458 | } | |
459 | } | |
460 | ||
461 | static int dissected_image_new(const char *path, DissectedImage **ret) { | |
462 | _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL; | |
463 | _cleanup_free_ char *name = NULL; | |
464 | int r; | |
465 | ||
466 | assert(ret); | |
467 | ||
468 | if (path) { | |
469 | _cleanup_free_ char *filename = NULL; | |
470 | ||
471 | r = path_extract_filename(path, &filename); | |
472 | if (r < 0) | |
473 | return r; | |
474 | ||
475 | r = raw_strip_suffixes(filename, &name); | |
476 | if (r < 0) | |
477 | return r; | |
478 | ||
479 | if (!image_name_is_valid(name)) { | |
480 | log_debug("Image name %s is not valid, ignoring.", strna(name)); | |
481 | name = mfree(name); | |
482 | } | |
483 | } | |
484 | ||
485 | m = new(DissectedImage, 1); | |
486 | if (!m) | |
487 | return -ENOMEM; | |
488 | ||
489 | *m = (DissectedImage) { | |
490 | .has_init_system = -1, | |
491 | .image_name = TAKE_PTR(name), | |
492 | }; | |
493 | ||
494 | for (PartitionDesignator i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) | |
495 | m->partitions[i] = DISSECTED_PARTITION_NULL; | |
496 | ||
497 | *ret = TAKE_PTR(m); | |
498 | return 0; | |
499 | } | |
500 | #endif | |
501 | ||
502 | static void dissected_partition_done(DissectedPartition *p) { | |
503 | assert(p); | |
504 | ||
505 | free(p->fstype); | |
506 | free(p->node); | |
507 | free(p->label); | |
508 | free(p->decrypted_fstype); | |
509 | free(p->decrypted_node); | |
510 | free(p->mount_options); | |
511 | safe_close(p->mount_node_fd); | |
512 | safe_close(p->fsmount_fd); | |
513 | ||
514 | *p = DISSECTED_PARTITION_NULL; | |
515 | } | |
516 | ||
517 | #if HAVE_BLKID | |
518 | static int make_partition_devname( | |
519 | const char *whole_devname, | |
520 | uint64_t diskseq, | |
521 | int nr, | |
522 | DissectImageFlags flags, | |
523 | char **ret) { | |
524 | ||
525 | _cleanup_free_ char *s = NULL; | |
526 | int r; | |
527 | ||
528 | assert(whole_devname); | |
529 | assert(nr != 0); /* zero is not a valid partition nr */ | |
530 | assert(ret); | |
531 | ||
532 | if (!FLAGS_SET(flags, DISSECT_IMAGE_DISKSEQ_DEVNODE) || diskseq == 0) { | |
533 | ||
534 | /* Given a whole block device node name (e.g. /dev/sda or /dev/loop7) generate a partition | |
535 | * device name (e.g. /dev/sda7 or /dev/loop7p5). The rule the kernel uses is simple: if whole | |
536 | * block device node name ends in a digit, then suffix a 'p', followed by the partition | |
537 | * number. Otherwise, just suffix the partition number without any 'p'. */ | |
538 | ||
539 | if (nr < 0) { /* whole disk? */ | |
540 | s = strdup(whole_devname); | |
541 | if (!s) | |
542 | return -ENOMEM; | |
543 | } else { | |
544 | size_t l = strlen(whole_devname); | |
545 | if (l < 1) /* underflow check for the subtraction below */ | |
546 | return -EINVAL; | |
547 | ||
548 | bool need_p = ascii_isdigit(whole_devname[l-1]); /* Last char a digit? */ | |
549 | ||
550 | if (asprintf(&s, "%s%s%i", whole_devname, need_p ? "p" : "", nr) < 0) | |
551 | return -ENOMEM; | |
552 | } | |
553 | } else { | |
554 | if (nr < 0) /* whole disk? */ | |
555 | r = asprintf(&s, "/dev/disk/by-diskseq/%" PRIu64, diskseq); | |
556 | else | |
557 | r = asprintf(&s, "/dev/disk/by-diskseq/%" PRIu64 "-part%i", diskseq, nr); | |
558 | if (r < 0) | |
559 | return -ENOMEM; | |
560 | } | |
561 | ||
562 | *ret = TAKE_PTR(s); | |
563 | return 0; | |
564 | } | |
565 | ||
566 | static int open_partition( | |
567 | const char *node, | |
568 | bool is_partition, | |
569 | const LoopDevice *loop) { | |
570 | ||
571 | _cleanup_(sd_device_unrefp) sd_device *dev = NULL; | |
572 | _cleanup_close_ int fd = -EBADF; | |
573 | dev_t devnum; | |
574 | int r; | |
575 | ||
576 | assert(node); | |
577 | assert(loop); | |
578 | ||
579 | fd = open(node, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); | |
580 | if (fd < 0) | |
581 | return -errno; | |
582 | ||
583 | /* Check if the block device is a child of (or equivalent to) the originally provided one. */ | |
584 | r = block_device_new_from_fd(fd, is_partition ? BLOCK_DEVICE_LOOKUP_WHOLE_DISK : 0, &dev); | |
585 | if (r < 0) | |
586 | return r; | |
587 | ||
588 | r = sd_device_get_devnum(dev, &devnum); | |
589 | if (r < 0) | |
590 | return r; | |
591 | ||
592 | if (loop->devno != devnum) | |
593 | return -ENXIO; | |
594 | ||
595 | /* Also check diskseq. */ | |
596 | if (loop->diskseq != 0) { | |
597 | uint64_t diskseq; | |
598 | ||
599 | r = fd_get_diskseq(fd, &diskseq); | |
600 | if (r < 0) | |
601 | return r; | |
602 | ||
603 | if (loop->diskseq != diskseq) | |
604 | return -ENXIO; | |
605 | } | |
606 | ||
607 | log_debug("Opened %s (fd=%i, whole_block_devnum=" DEVNUM_FORMAT_STR ", diskseq=%" PRIu64 ").", | |
608 | node, fd, DEVNUM_FORMAT_VAL(loop->devno), loop->diskseq); | |
609 | return TAKE_FD(fd); | |
610 | } | |
611 | ||
612 | static int compare_arch(Architecture a, Architecture b) { | |
613 | if (a == b) | |
614 | return 0; | |
615 | ||
616 | if (a == native_architecture()) | |
617 | return 1; | |
618 | ||
619 | if (b == native_architecture()) | |
620 | return -1; | |
621 | ||
622 | #ifdef ARCHITECTURE_SECONDARY | |
623 | if (a == ARCHITECTURE_SECONDARY) | |
624 | return 1; | |
625 | ||
626 | if (b == ARCHITECTURE_SECONDARY) | |
627 | return -1; | |
628 | #endif | |
629 | ||
630 | return 0; | |
631 | } | |
632 | ||
633 | static int dissect_image( | |
634 | DissectedImage *m, | |
635 | int fd, | |
636 | const char *devname, | |
637 | const VeritySettings *verity, | |
638 | const MountOptions *mount_options, | |
639 | const ImagePolicy *policy, | |
640 | DissectImageFlags flags) { | |
641 | ||
642 | sd_id128_t root_uuid = SD_ID128_NULL, root_verity_uuid = SD_ID128_NULL; | |
643 | sd_id128_t usr_uuid = SD_ID128_NULL, usr_verity_uuid = SD_ID128_NULL; | |
644 | bool is_gpt, is_mbr, multiple_generic = false, | |
645 | generic_rw = false, /* initialize to appease gcc */ | |
646 | generic_growfs = false; | |
647 | _cleanup_(blkid_free_probep) blkid_probe b = NULL; | |
648 | _cleanup_free_ char *generic_node = NULL; | |
649 | sd_id128_t generic_uuid = SD_ID128_NULL; | |
650 | const char *pttype = NULL, *sptuuid = NULL; | |
651 | blkid_partlist pl; | |
652 | int r, generic_nr = -1, n_partitions; | |
653 | ||
654 | assert(m); | |
655 | assert(fd >= 0); | |
656 | assert(devname); | |
657 | assert(!verity || verity->designator < 0 || IN_SET(verity->designator, PARTITION_ROOT, PARTITION_USR)); | |
658 | assert(!verity || verity->root_hash || verity->root_hash_size == 0); | |
659 | assert(!verity || verity->root_hash_sig || verity->root_hash_sig_size == 0); | |
660 | assert(!verity || (verity->root_hash || !verity->root_hash_sig)); | |
661 | assert(!((flags & DISSECT_IMAGE_GPT_ONLY) && (flags & DISSECT_IMAGE_NO_PARTITION_TABLE))); | |
662 | assert(m->sector_size > 0); | |
663 | ||
664 | /* Probes a disk image, and returns information about what it found in *ret. | |
665 | * | |
666 | * Returns -ENOPKG if no suitable partition table or file system could be found. | |
667 | * Returns -EADDRNOTAVAIL if a root hash was specified but no matching root/verity partitions found. | |
668 | * Returns -ENXIO if we couldn't find any partition suitable as root or /usr partition | |
669 | * Returns -ENOTUNIQ if we only found multiple generic partitions and thus don't know what to do with that | |
670 | * Returns -ERFKILL if image doesn't match image policy | |
671 | * Returns -EBADR if verity data was provided externally for an image that has a GPT partition table (i.e. is not just a naked fs) | |
672 | * Returns -EPROTONOSUPPORT if DISSECT_IMAGE_ADD_PARTITION_DEVICES is set but the block device does not have partition logic enabled | |
673 | * Returns -ENOMSG if we didn't find a single usable partition (and DISSECT_IMAGE_REFUSE_EMPTY is set) */ | |
674 | ||
675 | uint64_t diskseq = m->loop ? m->loop->diskseq : 0; | |
676 | ||
677 | if (verity && verity->root_hash) { | |
678 | sd_id128_t fsuuid, vuuid; | |
679 | ||
680 | /* If a root hash is supplied, then we use the root partition that has a UUID that match the | |
681 | * first 128-bit of the root hash. And we use the verity partition that has a UUID that match | |
682 | * the final 128-bit. */ | |
683 | ||
684 | if (verity->root_hash_size < sizeof(sd_id128_t)) | |
685 | return -EINVAL; | |
686 | ||
687 | memcpy(&fsuuid, verity->root_hash, sizeof(sd_id128_t)); | |
688 | memcpy(&vuuid, (const uint8_t*) verity->root_hash + verity->root_hash_size - sizeof(sd_id128_t), sizeof(sd_id128_t)); | |
689 | ||
690 | if (sd_id128_is_null(fsuuid)) | |
691 | return -EINVAL; | |
692 | if (sd_id128_is_null(vuuid)) | |
693 | return -EINVAL; | |
694 | ||
695 | /* If the verity data declares it's for the /usr partition, then search for that, in all | |
696 | * other cases assume it's for the root partition. */ | |
697 | if (verity->designator == PARTITION_USR) { | |
698 | usr_uuid = fsuuid; | |
699 | usr_verity_uuid = vuuid; | |
700 | } else { | |
701 | root_uuid = fsuuid; | |
702 | root_verity_uuid = vuuid; | |
703 | } | |
704 | } | |
705 | ||
706 | b = blkid_new_probe(); | |
707 | if (!b) | |
708 | return -ENOMEM; | |
709 | ||
710 | errno = 0; | |
711 | r = blkid_probe_set_device(b, fd, 0, 0); | |
712 | if (r != 0) | |
713 | return errno_or_else(ENOMEM); | |
714 | ||
715 | errno = 0; | |
716 | r = blkid_probe_set_sectorsize(b, m->sector_size); | |
717 | if (r != 0) | |
718 | return errno_or_else(EIO); | |
719 | ||
720 | if ((flags & DISSECT_IMAGE_GPT_ONLY) == 0) { | |
721 | /* Look for file system superblocks, unless we only shall look for GPT partition tables */ | |
722 | blkid_probe_enable_superblocks(b, 1); | |
723 | blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE|BLKID_SUBLKS_USAGE|BLKID_SUBLKS_UUID); | |
724 | } | |
725 | ||
726 | blkid_probe_enable_partitions(b, 1); | |
727 | blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS); | |
728 | ||
729 | errno = 0; | |
730 | r = blkid_do_safeprobe(b); | |
731 | if (r == _BLKID_SAFEPROBE_ERROR) | |
732 | return errno_or_else(EIO); | |
733 | if (IN_SET(r, _BLKID_SAFEPROBE_AMBIGUOUS, _BLKID_SAFEPROBE_NOT_FOUND)) | |
734 | return log_debug_errno(SYNTHETIC_ERRNO(ENOPKG), "Failed to identify any partition table."); | |
735 | ||
736 | assert(r == _BLKID_SAFEPROBE_FOUND); | |
737 | ||
738 | if ((!(flags & DISSECT_IMAGE_GPT_ONLY) && | |
739 | (flags & DISSECT_IMAGE_GENERIC_ROOT)) || | |
740 | (flags & DISSECT_IMAGE_NO_PARTITION_TABLE)) { | |
741 | const char *usage = NULL; | |
742 | ||
743 | /* If flags permit this, also allow using non-partitioned single-filesystem images */ | |
744 | ||
745 | (void) blkid_probe_lookup_value(b, "USAGE", &usage, NULL); | |
746 | if (STRPTR_IN_SET(usage, "filesystem", "crypto")) { | |
747 | _cleanup_free_ char *t = NULL, *n = NULL, *o = NULL; | |
748 | const char *fstype = NULL, *options = NULL, *suuid = NULL; | |
749 | _cleanup_close_ int mount_node_fd = -EBADF; | |
750 | sd_id128_t uuid = SD_ID128_NULL; | |
751 | PartitionPolicyFlags found_flags; | |
752 | bool encrypted; | |
753 | ||
754 | /* OK, we have found a file system, that's our root partition then. */ | |
755 | ||
756 | r = image_policy_may_use(policy, PARTITION_ROOT); | |
757 | if (r < 0) | |
758 | return r; | |
759 | if (r == 0) /* policy says ignore this, so we ignore it */ | |
760 | return -ENOPKG; | |
761 | ||
762 | (void) blkid_probe_lookup_value(b, "TYPE", &fstype, NULL); | |
763 | (void) blkid_probe_lookup_value(b, "UUID", &suuid, NULL); | |
764 | ||
765 | encrypted = streq_ptr(fstype, "crypto_LUKS"); | |
766 | ||
767 | if (verity_settings_data_covers(verity, PARTITION_ROOT)) | |
768 | found_flags = verity->root_hash_sig ? PARTITION_POLICY_SIGNED : PARTITION_POLICY_VERITY; | |
769 | else | |
770 | found_flags = encrypted ? PARTITION_POLICY_ENCRYPTED : PARTITION_POLICY_UNPROTECTED; | |
771 | ||
772 | r = image_policy_check_protection(policy, PARTITION_ROOT, found_flags); | |
773 | if (r < 0) | |
774 | return r; | |
775 | ||
776 | r = image_policy_check_partition_flags(policy, PARTITION_ROOT, 0); /* we have no gpt partition flags, hence check against all bits off */ | |
777 | if (r < 0) | |
778 | return r; | |
779 | ||
780 | if (FLAGS_SET(flags, DISSECT_IMAGE_PIN_PARTITION_DEVICES)) { | |
781 | mount_node_fd = open_partition(devname, /* is_partition = */ false, m->loop); | |
782 | if (mount_node_fd < 0) | |
783 | return mount_node_fd; | |
784 | } | |
785 | ||
786 | if (fstype) { | |
787 | t = strdup(fstype); | |
788 | if (!t) | |
789 | return -ENOMEM; | |
790 | } | |
791 | ||
792 | if (suuid) { | |
793 | /* blkid will return FAT's serial number as UUID, hence it is quite possible | |
794 | * that parsing this will fail. We'll ignore the ID, since it's just too | |
795 | * short to be useful as true identifier. */ | |
796 | r = sd_id128_from_string(suuid, &uuid); | |
797 | if (r < 0) | |
798 | log_debug_errno(r, "Failed to parse file system UUID '%s', ignoring: %m", suuid); | |
799 | } | |
800 | ||
801 | r = make_partition_devname(devname, diskseq, -1, flags, &n); | |
802 | if (r < 0) | |
803 | return r; | |
804 | ||
805 | m->single_file_system = true; | |
806 | m->encrypted = encrypted; | |
807 | ||
808 | m->has_verity = verity && verity->data_path; | |
809 | m->verity_ready = verity_settings_data_covers(verity, PARTITION_ROOT); | |
810 | ||
811 | m->has_verity_sig = false; /* signature not embedded, must be specified */ | |
812 | m->verity_sig_ready = m->verity_ready && verity->root_hash_sig; | |
813 | ||
814 | m->image_uuid = uuid; | |
815 | ||
816 | options = mount_options_from_designator(mount_options, PARTITION_ROOT); | |
817 | if (options) { | |
818 | o = strdup(options); | |
819 | if (!o) | |
820 | return -ENOMEM; | |
821 | } | |
822 | ||
823 | m->partitions[PARTITION_ROOT] = (DissectedPartition) { | |
824 | .found = true, | |
825 | .rw = !m->verity_ready && !fstype_is_ro(fstype), | |
826 | .partno = -1, | |
827 | .architecture = _ARCHITECTURE_INVALID, | |
828 | .fstype = TAKE_PTR(t), | |
829 | .node = TAKE_PTR(n), | |
830 | .mount_options = TAKE_PTR(o), | |
831 | .mount_node_fd = TAKE_FD(mount_node_fd), | |
832 | .offset = 0, | |
833 | .size = UINT64_MAX, | |
834 | .fsmount_fd = -EBADF, | |
835 | }; | |
836 | ||
837 | return 0; | |
838 | } | |
839 | } | |
840 | ||
841 | (void) blkid_probe_lookup_value(b, "PTTYPE", &pttype, NULL); | |
842 | if (!pttype) | |
843 | return -ENOPKG; | |
844 | ||
845 | is_gpt = streq_ptr(pttype, "gpt"); | |
846 | is_mbr = streq_ptr(pttype, "dos"); | |
847 | ||
848 | if (!is_gpt && ((flags & DISSECT_IMAGE_GPT_ONLY) || !is_mbr)) | |
849 | return -ENOPKG; | |
850 | ||
851 | /* We support external verity data partitions only if the image has no partition table */ | |
852 | if (verity && verity->data_path) | |
853 | return -EBADR; | |
854 | ||
855 | if (FLAGS_SET(flags, DISSECT_IMAGE_ADD_PARTITION_DEVICES)) { | |
856 | /* Safety check: refuse block devices that carry a partition table but for which the kernel doesn't | |
857 | * do partition scanning. */ | |
858 | r = blockdev_partscan_enabled(fd); | |
859 | if (r < 0) | |
860 | return r; | |
861 | if (r == 0) | |
862 | return -EPROTONOSUPPORT; | |
863 | } | |
864 | ||
865 | (void) blkid_probe_lookup_value(b, "PTUUID", &sptuuid, NULL); | |
866 | if (sptuuid) { | |
867 | r = sd_id128_from_string(sptuuid, &m->image_uuid); | |
868 | if (r < 0) | |
869 | log_debug_errno(r, "Failed to parse partition table UUID '%s', ignoring: %m", sptuuid); | |
870 | } | |
871 | ||
872 | errno = 0; | |
873 | pl = blkid_probe_get_partitions(b); | |
874 | if (!pl) | |
875 | return errno_or_else(ENOMEM); | |
876 | ||
877 | errno = 0; | |
878 | n_partitions = blkid_partlist_numof_partitions(pl); | |
879 | if (n_partitions < 0) | |
880 | return errno_or_else(EIO); | |
881 | ||
882 | for (int i = 0; i < n_partitions; i++) { | |
883 | _cleanup_free_ char *node = NULL; | |
884 | unsigned long long pflags; | |
885 | blkid_loff_t start, size; | |
886 | blkid_partition pp; | |
887 | int nr; | |
888 | ||
889 | errno = 0; | |
890 | pp = blkid_partlist_get_partition(pl, i); | |
891 | if (!pp) | |
892 | return errno_or_else(EIO); | |
893 | ||
894 | pflags = blkid_partition_get_flags(pp); | |
895 | ||
896 | errno = 0; | |
897 | nr = blkid_partition_get_partno(pp); | |
898 | if (nr < 0) | |
899 | return errno_or_else(EIO); | |
900 | ||
901 | errno = 0; | |
902 | start = blkid_partition_get_start(pp); | |
903 | if (start < 0) | |
904 | return errno_or_else(EIO); | |
905 | ||
906 | assert((uint64_t) start < UINT64_MAX/512); | |
907 | ||
908 | errno = 0; | |
909 | size = blkid_partition_get_size(pp); | |
910 | if (size < 0) | |
911 | return errno_or_else(EIO); | |
912 | ||
913 | assert((uint64_t) size < UINT64_MAX/512); | |
914 | ||
915 | /* While probing we need the non-diskseq device node name to access the thing, hence mask off | |
916 | * DISSECT_IMAGE_DISKSEQ_DEVNODE. */ | |
917 | r = make_partition_devname(devname, diskseq, nr, flags & ~DISSECT_IMAGE_DISKSEQ_DEVNODE, &node); | |
918 | if (r < 0) | |
919 | return r; | |
920 | ||
921 | /* So here's the thing: after the main ("whole") block device popped up it might take a while | |
922 | * before the kernel fully probed the partition table. Waiting for that to finish is icky in | |
923 | * userspace. So here's what we do instead. We issue the BLKPG_ADD_PARTITION ioctl to add the | |
924 | * partition ourselves, racing against the kernel. Good thing is: if this call fails with | |
925 | * EBUSY then the kernel was quicker than us, and that's totally OK, the outcome is good for | |
926 | * us: the device node will exist. If OTOH our call was successful we won the race. Which is | |
927 | * also good as the outcome is the same: the partition block device exists, and we can use | |
928 | * it. | |
929 | * | |
930 | * Kernel returns EBUSY if there's already a partition by that number or an overlapping | |
931 | * partition already existent. */ | |
932 | ||
933 | if (FLAGS_SET(flags, DISSECT_IMAGE_ADD_PARTITION_DEVICES)) { | |
934 | r = block_device_add_partition(fd, node, nr, (uint64_t) start * 512, (uint64_t) size * 512); | |
935 | if (r < 0) { | |
936 | if (r != -EBUSY) | |
937 | return log_debug_errno(r, "BLKPG_ADD_PARTITION failed: %m"); | |
938 | ||
939 | log_debug_errno(r, "Kernel was quicker than us in adding partition %i.", nr); | |
940 | } else | |
941 | log_debug("We were quicker than kernel in adding partition %i.", nr); | |
942 | } | |
943 | ||
944 | if (is_gpt) { | |
945 | const char *fstype = NULL, *label; | |
946 | sd_id128_t type_id, id; | |
947 | GptPartitionType type; | |
948 | bool rw = true, growfs = false; | |
949 | ||
950 | r = blkid_partition_get_uuid_id128(pp, &id); | |
951 | if (r < 0) { | |
952 | log_debug_errno(r, "Failed to read partition UUID, ignoring: %m"); | |
953 | continue; | |
954 | } | |
955 | ||
956 | r = blkid_partition_get_type_id128(pp, &type_id); | |
957 | if (r < 0) { | |
958 | log_debug_errno(r, "Failed to read partition type UUID, ignoring: %m"); | |
959 | continue; | |
960 | } | |
961 | ||
962 | type = gpt_partition_type_from_uuid(type_id); | |
963 | ||
964 | label = blkid_partition_get_name(pp); /* libblkid returns NULL here if empty */ | |
965 | ||
966 | if (IN_SET(type.designator, | |
967 | PARTITION_HOME, | |
968 | PARTITION_SRV, | |
969 | PARTITION_XBOOTLDR, | |
970 | PARTITION_TMP)) { | |
971 | ||
972 | check_partition_flags(node, pflags, | |
973 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY | SD_GPT_FLAG_GROWFS); | |
974 | ||
975 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
976 | continue; | |
977 | ||
978 | rw = !(pflags & SD_GPT_FLAG_READ_ONLY); | |
979 | growfs = FLAGS_SET(pflags, SD_GPT_FLAG_GROWFS); | |
980 | ||
981 | } else if (type.designator == PARTITION_ESP) { | |
982 | ||
983 | /* Note that we don't check the SD_GPT_FLAG_NO_AUTO flag for the ESP, as it is | |
984 | * not defined there. We instead check the SD_GPT_FLAG_NO_BLOCK_IO_PROTOCOL, as | |
985 | * recommended by the UEFI spec (See "12.3.3 Number and Location of System | |
986 | * Partitions"). */ | |
987 | ||
988 | if (pflags & SD_GPT_FLAG_NO_BLOCK_IO_PROTOCOL) | |
989 | continue; | |
990 | ||
991 | fstype = "vfat"; | |
992 | ||
993 | } else if (type.designator == PARTITION_ROOT) { | |
994 | ||
995 | check_partition_flags(node, pflags, | |
996 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY | SD_GPT_FLAG_GROWFS); | |
997 | ||
998 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
999 | continue; | |
1000 | ||
1001 | /* If a root ID is specified, ignore everything but the root id */ | |
1002 | if (!sd_id128_is_null(root_uuid) && !sd_id128_equal(root_uuid, id)) | |
1003 | continue; | |
1004 | ||
1005 | rw = !(pflags & SD_GPT_FLAG_READ_ONLY); | |
1006 | growfs = FLAGS_SET(pflags, SD_GPT_FLAG_GROWFS); | |
1007 | ||
1008 | } else if (type.designator == PARTITION_ROOT_VERITY) { | |
1009 | ||
1010 | check_partition_flags(node, pflags, | |
1011 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY); | |
1012 | ||
1013 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1014 | continue; | |
1015 | ||
1016 | m->has_verity = true; | |
1017 | ||
1018 | /* If no verity configuration is specified, then don't do verity */ | |
1019 | if (!verity) | |
1020 | continue; | |
1021 | if (verity->designator >= 0 && verity->designator != PARTITION_ROOT) | |
1022 | continue; | |
1023 | ||
1024 | /* If root hash is specified, then ignore everything but the root id */ | |
1025 | if (!sd_id128_is_null(root_verity_uuid) && !sd_id128_equal(root_verity_uuid, id)) | |
1026 | continue; | |
1027 | ||
1028 | fstype = "DM_verity_hash"; | |
1029 | rw = false; | |
1030 | ||
1031 | } else if (type.designator == PARTITION_ROOT_VERITY_SIG) { | |
1032 | ||
1033 | check_partition_flags(node, pflags, | |
1034 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY); | |
1035 | ||
1036 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1037 | continue; | |
1038 | ||
1039 | m->has_verity_sig = true; | |
1040 | ||
1041 | if (!verity) | |
1042 | continue; | |
1043 | if (verity->designator >= 0 && verity->designator != PARTITION_ROOT) | |
1044 | continue; | |
1045 | ||
1046 | fstype = "verity_hash_signature"; | |
1047 | rw = false; | |
1048 | ||
1049 | } else if (type.designator == PARTITION_USR) { | |
1050 | ||
1051 | check_partition_flags(node, pflags, | |
1052 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY | SD_GPT_FLAG_GROWFS); | |
1053 | ||
1054 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1055 | continue; | |
1056 | ||
1057 | /* If a usr ID is specified, ignore everything but the usr id */ | |
1058 | if (!sd_id128_is_null(usr_uuid) && !sd_id128_equal(usr_uuid, id)) | |
1059 | continue; | |
1060 | ||
1061 | rw = !(pflags & SD_GPT_FLAG_READ_ONLY); | |
1062 | growfs = FLAGS_SET(pflags, SD_GPT_FLAG_GROWFS); | |
1063 | ||
1064 | } else if (type.designator == PARTITION_USR_VERITY) { | |
1065 | ||
1066 | check_partition_flags(node, pflags, | |
1067 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY); | |
1068 | ||
1069 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1070 | continue; | |
1071 | ||
1072 | m->has_verity = true; | |
1073 | ||
1074 | if (!verity) | |
1075 | continue; | |
1076 | if (verity->designator >= 0 && verity->designator != PARTITION_USR) | |
1077 | continue; | |
1078 | ||
1079 | /* If usr hash is specified, then ignore everything but the usr id */ | |
1080 | if (!sd_id128_is_null(usr_verity_uuid) && !sd_id128_equal(usr_verity_uuid, id)) | |
1081 | continue; | |
1082 | ||
1083 | fstype = "DM_verity_hash"; | |
1084 | rw = false; | |
1085 | ||
1086 | } else if (type.designator == PARTITION_USR_VERITY_SIG) { | |
1087 | ||
1088 | check_partition_flags(node, pflags, | |
1089 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY); | |
1090 | ||
1091 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1092 | continue; | |
1093 | ||
1094 | m->has_verity_sig = true; | |
1095 | ||
1096 | if (!verity) | |
1097 | continue; | |
1098 | if (verity->designator >= 0 && verity->designator != PARTITION_USR) | |
1099 | continue; | |
1100 | ||
1101 | fstype = "verity_hash_signature"; | |
1102 | rw = false; | |
1103 | ||
1104 | } else if (type.designator == PARTITION_SWAP) { | |
1105 | ||
1106 | check_partition_flags(node, pflags, SD_GPT_FLAG_NO_AUTO); | |
1107 | ||
1108 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1109 | continue; | |
1110 | ||
1111 | /* Note: we don't set fstype = "swap" here, because we still need to probe if | |
1112 | * it might be encrypted (i.e. fstype "crypt_LUKS") or unencrypted | |
1113 | * (i.e. fstype "swap"), and the only way to figure that out is via fstype | |
1114 | * probing. */ | |
1115 | ||
1116 | /* We don't have a designator for SD_GPT_LINUX_GENERIC so check the UUID instead. */ | |
1117 | } else if (sd_id128_equal(type.uuid, SD_GPT_LINUX_GENERIC)) { | |
1118 | ||
1119 | check_partition_flags(node, pflags, | |
1120 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY | SD_GPT_FLAG_GROWFS); | |
1121 | ||
1122 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1123 | continue; | |
1124 | ||
1125 | if (generic_node) | |
1126 | multiple_generic = true; | |
1127 | else { | |
1128 | generic_nr = nr; | |
1129 | generic_rw = !(pflags & SD_GPT_FLAG_READ_ONLY); | |
1130 | generic_growfs = FLAGS_SET(pflags, SD_GPT_FLAG_GROWFS); | |
1131 | generic_uuid = id; | |
1132 | generic_node = TAKE_PTR(node); | |
1133 | } | |
1134 | ||
1135 | } else if (type.designator == PARTITION_VAR) { | |
1136 | ||
1137 | check_partition_flags(node, pflags, | |
1138 | SD_GPT_FLAG_NO_AUTO | SD_GPT_FLAG_READ_ONLY | SD_GPT_FLAG_GROWFS); | |
1139 | ||
1140 | if (pflags & SD_GPT_FLAG_NO_AUTO) | |
1141 | continue; | |
1142 | ||
1143 | if (!FLAGS_SET(flags, DISSECT_IMAGE_RELAX_VAR_CHECK)) { | |
1144 | sd_id128_t var_uuid; | |
1145 | ||
1146 | /* For /var we insist that the uuid of the partition matches the | |
1147 | * HMAC-SHA256 of the /var GPT partition type uuid, keyed by machine | |
1148 | * ID. Why? Unlike the other partitions /var is inherently | |
1149 | * installation specific, hence we need to be careful not to mount it | |
1150 | * in the wrong installation. By hashing the partition UUID from | |
1151 | * /etc/machine-id we can securely bind the partition to the | |
1152 | * installation. */ | |
1153 | ||
1154 | r = sd_id128_get_machine_app_specific(SD_GPT_VAR, &var_uuid); | |
1155 | if (r < 0) | |
1156 | return r; | |
1157 | ||
1158 | if (!sd_id128_equal(var_uuid, id)) { | |
1159 | log_debug("Found a /var/ partition, but its UUID didn't match our expectations " | |
1160 | "(found: " SD_ID128_UUID_FORMAT_STR ", expected: " SD_ID128_UUID_FORMAT_STR "), ignoring.", | |
1161 | SD_ID128_FORMAT_VAL(id), SD_ID128_FORMAT_VAL(var_uuid)); | |
1162 | continue; | |
1163 | } | |
1164 | } | |
1165 | ||
1166 | rw = !(pflags & SD_GPT_FLAG_READ_ONLY); | |
1167 | growfs = FLAGS_SET(pflags, SD_GPT_FLAG_GROWFS); | |
1168 | } | |
1169 | ||
1170 | if (type.designator != _PARTITION_DESIGNATOR_INVALID) { | |
1171 | _cleanup_free_ char *t = NULL, *o = NULL, *l = NULL, *n = NULL; | |
1172 | _cleanup_close_ int mount_node_fd = -EBADF; | |
1173 | const char *options = NULL; | |
1174 | ||
1175 | r = image_policy_may_use(policy, type.designator); | |
1176 | if (r < 0) | |
1177 | return r; | |
1178 | if (r == 0) { | |
1179 | /* Policy says: ignore; Remember this fact, so that we later can distinguish between "found but ignored" and "not found at all" */ | |
1180 | ||
1181 | if (!m->partitions[type.designator].found) | |
1182 | m->partitions[type.designator].ignored = true; | |
1183 | ||
1184 | continue; | |
1185 | } | |
1186 | ||
1187 | if (m->partitions[type.designator].found) { | |
1188 | int c; | |
1189 | ||
1190 | /* For most partition types the first one we see wins. Except for the | |
1191 | * rootfs and /usr, where we do a version compare of the label, and | |
1192 | * let the newest version win. This permits a simple A/B versioning | |
1193 | * scheme in OS images. */ | |
1194 | ||
1195 | c = compare_arch(type.arch, m->partitions[type.designator].architecture); | |
1196 | if (c < 0) /* the arch we already found is better than the one we found now */ | |
1197 | continue; | |
1198 | if (c == 0 && /* same arch? then go by version in label */ | |
1199 | (!partition_designator_is_versioned(type.designator) || | |
1200 | strverscmp_improved(label, m->partitions[type.designator].label) <= 0)) | |
1201 | continue; | |
1202 | ||
1203 | dissected_partition_done(m->partitions + type.designator); | |
1204 | } | |
1205 | ||
1206 | if (FLAGS_SET(flags, DISSECT_IMAGE_PIN_PARTITION_DEVICES) && | |
1207 | type.designator != PARTITION_SWAP) { | |
1208 | mount_node_fd = open_partition(node, /* is_partition = */ true, m->loop); | |
1209 | if (mount_node_fd < 0) | |
1210 | return mount_node_fd; | |
1211 | } | |
1212 | ||
1213 | r = make_partition_devname(devname, diskseq, nr, flags, &n); | |
1214 | if (r < 0) | |
1215 | return r; | |
1216 | ||
1217 | if (fstype) { | |
1218 | t = strdup(fstype); | |
1219 | if (!t) | |
1220 | return -ENOMEM; | |
1221 | } | |
1222 | ||
1223 | if (label) { | |
1224 | l = strdup(label); | |
1225 | if (!l) | |
1226 | return -ENOMEM; | |
1227 | } | |
1228 | ||
1229 | options = mount_options_from_designator(mount_options, type.designator); | |
1230 | if (options) { | |
1231 | o = strdup(options); | |
1232 | if (!o) | |
1233 | return -ENOMEM; | |
1234 | } | |
1235 | ||
1236 | m->partitions[type.designator] = (DissectedPartition) { | |
1237 | .found = true, | |
1238 | .partno = nr, | |
1239 | .rw = rw, | |
1240 | .growfs = growfs, | |
1241 | .architecture = type.arch, | |
1242 | .node = TAKE_PTR(n), | |
1243 | .fstype = TAKE_PTR(t), | |
1244 | .label = TAKE_PTR(l), | |
1245 | .uuid = id, | |
1246 | .mount_options = TAKE_PTR(o), | |
1247 | .mount_node_fd = TAKE_FD(mount_node_fd), | |
1248 | .offset = (uint64_t) start * 512, | |
1249 | .size = (uint64_t) size * 512, | |
1250 | .gpt_flags = pflags, | |
1251 | .fsmount_fd = -EBADF, | |
1252 | }; | |
1253 | } | |
1254 | ||
1255 | } else if (is_mbr) { | |
1256 | ||
1257 | switch (blkid_partition_get_type(pp)) { | |
1258 | ||
1259 | case 0x83: /* Linux partition */ | |
1260 | ||
1261 | if (pflags != 0x80) /* Bootable flag */ | |
1262 | continue; | |
1263 | ||
1264 | if (generic_node) | |
1265 | multiple_generic = true; | |
1266 | else { | |
1267 | generic_nr = nr; | |
1268 | generic_rw = true; | |
1269 | generic_growfs = false; | |
1270 | generic_node = TAKE_PTR(node); | |
1271 | } | |
1272 | ||
1273 | break; | |
1274 | ||
1275 | case 0xEA: { /* Boot Loader Spec extended $BOOT partition */ | |
1276 | _cleanup_close_ int mount_node_fd = -EBADF; | |
1277 | _cleanup_free_ char *o = NULL, *n = NULL; | |
1278 | sd_id128_t id = SD_ID128_NULL; | |
1279 | const char *options = NULL; | |
1280 | ||
1281 | r = image_policy_may_use(policy, PARTITION_XBOOTLDR); | |
1282 | if (r < 0) | |
1283 | return r; | |
1284 | if (r == 0) { /* policy says: ignore */ | |
1285 | if (!m->partitions[PARTITION_XBOOTLDR].found) | |
1286 | m->partitions[PARTITION_XBOOTLDR].ignored = true; | |
1287 | ||
1288 | continue; | |
1289 | } | |
1290 | ||
1291 | /* First one wins */ | |
1292 | if (m->partitions[PARTITION_XBOOTLDR].found) | |
1293 | continue; | |
1294 | ||
1295 | if (FLAGS_SET(flags, DISSECT_IMAGE_PIN_PARTITION_DEVICES)) { | |
1296 | mount_node_fd = open_partition(node, /* is_partition = */ true, m->loop); | |
1297 | if (mount_node_fd < 0) | |
1298 | return mount_node_fd; | |
1299 | } | |
1300 | ||
1301 | (void) blkid_partition_get_uuid_id128(pp, &id); | |
1302 | ||
1303 | r = make_partition_devname(devname, diskseq, nr, flags, &n); | |
1304 | if (r < 0) | |
1305 | return r; | |
1306 | ||
1307 | options = mount_options_from_designator(mount_options, PARTITION_XBOOTLDR); | |
1308 | if (options) { | |
1309 | o = strdup(options); | |
1310 | if (!o) | |
1311 | return -ENOMEM; | |
1312 | } | |
1313 | ||
1314 | m->partitions[PARTITION_XBOOTLDR] = (DissectedPartition) { | |
1315 | .found = true, | |
1316 | .partno = nr, | |
1317 | .rw = true, | |
1318 | .growfs = false, | |
1319 | .architecture = _ARCHITECTURE_INVALID, | |
1320 | .node = TAKE_PTR(n), | |
1321 | .uuid = id, | |
1322 | .mount_options = TAKE_PTR(o), | |
1323 | .mount_node_fd = TAKE_FD(mount_node_fd), | |
1324 | .offset = (uint64_t) start * 512, | |
1325 | .size = (uint64_t) size * 512, | |
1326 | .fsmount_fd = -EBADF, | |
1327 | }; | |
1328 | ||
1329 | break; | |
1330 | }} | |
1331 | } | |
1332 | } | |
1333 | ||
1334 | if (!m->partitions[PARTITION_ROOT].found && | |
1335 | (m->partitions[PARTITION_ROOT_VERITY].found || | |
1336 | m->partitions[PARTITION_ROOT_VERITY_SIG].found)) | |
1337 | return -EADDRNOTAVAIL; /* Verity found but no matching rootfs? Something is off, refuse. */ | |
1338 | ||
1339 | /* Hmm, we found a signature partition but no Verity data? Something is off. */ | |
1340 | if (m->partitions[PARTITION_ROOT_VERITY_SIG].found && !m->partitions[PARTITION_ROOT_VERITY].found) | |
1341 | return -EADDRNOTAVAIL; | |
1342 | ||
1343 | if (!m->partitions[PARTITION_USR].found && | |
1344 | (m->partitions[PARTITION_USR_VERITY].found || | |
1345 | m->partitions[PARTITION_USR_VERITY_SIG].found)) | |
1346 | return -EADDRNOTAVAIL; /* as above */ | |
1347 | ||
1348 | /* as above */ | |
1349 | if (m->partitions[PARTITION_USR_VERITY_SIG].found && !m->partitions[PARTITION_USR_VERITY].found) | |
1350 | return -EADDRNOTAVAIL; | |
1351 | ||
1352 | /* If root and /usr are combined then insist that the architecture matches */ | |
1353 | if (m->partitions[PARTITION_ROOT].found && | |
1354 | m->partitions[PARTITION_USR].found && | |
1355 | (m->partitions[PARTITION_ROOT].architecture >= 0 && | |
1356 | m->partitions[PARTITION_USR].architecture >= 0 && | |
1357 | m->partitions[PARTITION_ROOT].architecture != m->partitions[PARTITION_USR].architecture)) | |
1358 | return -EADDRNOTAVAIL; | |
1359 | ||
1360 | if (!m->partitions[PARTITION_ROOT].found && | |
1361 | !m->partitions[PARTITION_USR].found && | |
1362 | (flags & DISSECT_IMAGE_GENERIC_ROOT) && | |
1363 | (!verity || !verity->root_hash || verity->designator != PARTITION_USR)) { | |
1364 | ||
1365 | /* OK, we found nothing usable, then check if there's a single generic partition, and use | |
1366 | * that. If the root hash was set however, then we won't fall back to a generic node, because | |
1367 | * the root hash decides. */ | |
1368 | ||
1369 | /* If we didn't find a properly marked root partition, but we did find a single suitable | |
1370 | * generic Linux partition, then use this as root partition, if the caller asked for it. */ | |
1371 | if (multiple_generic) | |
1372 | return -ENOTUNIQ; | |
1373 | ||
1374 | /* If we didn't find a generic node, then we can't fix this up either */ | |
1375 | if (generic_node) { | |
1376 | r = image_policy_may_use(policy, PARTITION_ROOT); | |
1377 | if (r < 0) | |
1378 | return r; | |
1379 | if (r == 0) | |
1380 | /* Policy says: ignore; remember that we did */ | |
1381 | m->partitions[PARTITION_ROOT].ignored = true; | |
1382 | else { | |
1383 | _cleanup_close_ int mount_node_fd = -EBADF; | |
1384 | _cleanup_free_ char *o = NULL, *n = NULL; | |
1385 | const char *options; | |
1386 | ||
1387 | if (FLAGS_SET(flags, DISSECT_IMAGE_PIN_PARTITION_DEVICES)) { | |
1388 | mount_node_fd = open_partition(generic_node, /* is_partition = */ true, m->loop); | |
1389 | if (mount_node_fd < 0) | |
1390 | return mount_node_fd; | |
1391 | } | |
1392 | ||
1393 | r = make_partition_devname(devname, diskseq, generic_nr, flags, &n); | |
1394 | if (r < 0) | |
1395 | return r; | |
1396 | ||
1397 | options = mount_options_from_designator(mount_options, PARTITION_ROOT); | |
1398 | if (options) { | |
1399 | o = strdup(options); | |
1400 | if (!o) | |
1401 | return -ENOMEM; | |
1402 | } | |
1403 | ||
1404 | assert(generic_nr >= 0); | |
1405 | m->partitions[PARTITION_ROOT] = (DissectedPartition) { | |
1406 | .found = true, | |
1407 | .rw = generic_rw, | |
1408 | .growfs = generic_growfs, | |
1409 | .partno = generic_nr, | |
1410 | .architecture = _ARCHITECTURE_INVALID, | |
1411 | .node = TAKE_PTR(n), | |
1412 | .uuid = generic_uuid, | |
1413 | .mount_options = TAKE_PTR(o), | |
1414 | .mount_node_fd = TAKE_FD(mount_node_fd), | |
1415 | .offset = UINT64_MAX, | |
1416 | .size = UINT64_MAX, | |
1417 | .fsmount_fd = -EBADF, | |
1418 | }; | |
1419 | } | |
1420 | } | |
1421 | } | |
1422 | ||
1423 | /* Check if we have a root fs if we are told to do check. /usr alone is fine too, but only if appropriate flag for that is set too */ | |
1424 | if (FLAGS_SET(flags, DISSECT_IMAGE_REQUIRE_ROOT) && | |
1425 | !(m->partitions[PARTITION_ROOT].found || (m->partitions[PARTITION_USR].found && FLAGS_SET(flags, DISSECT_IMAGE_USR_NO_ROOT)))) | |
1426 | return -ENXIO; | |
1427 | ||
1428 | if (m->partitions[PARTITION_ROOT_VERITY].found) { | |
1429 | /* We only support one verity partition per image, i.e. can't do for both /usr and root fs */ | |
1430 | if (m->partitions[PARTITION_USR_VERITY].found) | |
1431 | return -ENOTUNIQ; | |
1432 | ||
1433 | /* We don't support verity enabled root with a split out /usr. Neither with nor without | |
1434 | * verity there. (Note that we do support verity-less root with verity-full /usr, though.) */ | |
1435 | if (m->partitions[PARTITION_USR].found) | |
1436 | return -EADDRNOTAVAIL; | |
1437 | } | |
1438 | ||
1439 | if (verity) { | |
1440 | /* If a verity designator is specified, then insist that the matching partition exists */ | |
1441 | if (verity->designator >= 0 && !m->partitions[verity->designator].found) | |
1442 | return -EADDRNOTAVAIL; | |
1443 | ||
1444 | bool have_verity_sig_partition; | |
1445 | if (verity->designator >= 0) | |
1446 | have_verity_sig_partition = m->partitions[verity->designator == PARTITION_USR ? PARTITION_USR_VERITY_SIG : PARTITION_ROOT_VERITY_SIG].found; | |
1447 | else | |
1448 | have_verity_sig_partition = m->partitions[PARTITION_USR_VERITY_SIG].found || m->partitions[PARTITION_ROOT_VERITY_SIG].found; | |
1449 | ||
1450 | if (verity->root_hash) { | |
1451 | /* If we have an explicit root hash and found the partitions for it, then we are ready to use | |
1452 | * Verity, set things up for it */ | |
1453 | ||
1454 | if (verity->designator < 0 || verity->designator == PARTITION_ROOT) { | |
1455 | if (!m->partitions[PARTITION_ROOT_VERITY].found || !m->partitions[PARTITION_ROOT].found) | |
1456 | return -EADDRNOTAVAIL; | |
1457 | ||
1458 | /* If we found a verity setup, then the root partition is necessarily read-only. */ | |
1459 | m->partitions[PARTITION_ROOT].rw = false; | |
1460 | m->verity_ready = true; | |
1461 | ||
1462 | } else { | |
1463 | assert(verity->designator == PARTITION_USR); | |
1464 | ||
1465 | if (!m->partitions[PARTITION_USR_VERITY].found || !m->partitions[PARTITION_USR].found) | |
1466 | return -EADDRNOTAVAIL; | |
1467 | ||
1468 | m->partitions[PARTITION_USR].rw = false; | |
1469 | m->verity_ready = true; | |
1470 | } | |
1471 | ||
1472 | if (m->verity_ready) | |
1473 | m->verity_sig_ready = verity->root_hash_sig || have_verity_sig_partition; | |
1474 | ||
1475 | } else if (have_verity_sig_partition) { | |
1476 | ||
1477 | /* If we found an embedded signature partition, we are ready, too. */ | |
1478 | ||
1479 | m->verity_ready = m->verity_sig_ready = true; | |
1480 | if (verity->designator >= 0) | |
1481 | m->partitions[verity->designator == PARTITION_USR ? PARTITION_USR : PARTITION_ROOT].rw = false; | |
1482 | else if (m->partitions[PARTITION_USR_VERITY_SIG].found) | |
1483 | m->partitions[PARTITION_USR].rw = false; | |
1484 | else if (m->partitions[PARTITION_ROOT_VERITY_SIG].found) | |
1485 | m->partitions[PARTITION_ROOT].rw = false; | |
1486 | } | |
1487 | } | |
1488 | ||
1489 | bool any = false; | |
1490 | ||
1491 | /* After we discovered all partitions let's see if the verity requirements match the policy. (Note: | |
1492 | * we don't check encryption requirements here, because we haven't probed the file system yet, hence | |
1493 | * don't know if this is encrypted or not) */ | |
1494 | for (PartitionDesignator di = 0; di < _PARTITION_DESIGNATOR_MAX; di++) { | |
1495 | PartitionDesignator vi, si; | |
1496 | PartitionPolicyFlags found_flags; | |
1497 | ||
1498 | any = any || m->partitions[di].found; | |
1499 | ||
1500 | vi = partition_verity_of(di); | |
1501 | si = partition_verity_sig_of(di); | |
1502 | ||
1503 | /* Determine the verity protection level for this partition. */ | |
1504 | found_flags = m->partitions[di].found ? | |
1505 | (vi >= 0 && m->partitions[vi].found ? | |
1506 | (si >= 0 && m->partitions[si].found ? PARTITION_POLICY_SIGNED : PARTITION_POLICY_VERITY) : | |
1507 | PARTITION_POLICY_ENCRYPTED|PARTITION_POLICY_UNPROTECTED) : | |
1508 | (m->partitions[di].ignored ? PARTITION_POLICY_UNUSED : PARTITION_POLICY_ABSENT); | |
1509 | ||
1510 | r = image_policy_check_protection(policy, di, found_flags); | |
1511 | if (r < 0) | |
1512 | return r; | |
1513 | ||
1514 | if (m->partitions[di].found) { | |
1515 | r = image_policy_check_partition_flags(policy, di, m->partitions[di].gpt_flags); | |
1516 | if (r < 0) | |
1517 | return r; | |
1518 | } | |
1519 | } | |
1520 | ||
1521 | if (!any && !FLAGS_SET(flags, DISSECT_IMAGE_ALLOW_EMPTY)) | |
1522 | return -ENOMSG; | |
1523 | ||
1524 | r = dissected_image_probe_filesystems(m, fd, policy); | |
1525 | if (r < 0) | |
1526 | return r; | |
1527 | ||
1528 | return 0; | |
1529 | } | |
1530 | #endif | |
1531 | ||
1532 | int dissect_image_file( | |
1533 | const char *path, | |
1534 | const VeritySettings *verity, | |
1535 | const MountOptions *mount_options, | |
1536 | const ImagePolicy *image_policy, | |
1537 | DissectImageFlags flags, | |
1538 | DissectedImage **ret) { | |
1539 | ||
1540 | #if HAVE_BLKID | |
1541 | _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL; | |
1542 | _cleanup_close_ int fd = -EBADF; | |
1543 | struct stat st; | |
1544 | int r; | |
1545 | ||
1546 | assert(path); | |
1547 | ||
1548 | fd = open(path, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); | |
1549 | if (fd < 0) | |
1550 | return -errno; | |
1551 | ||
1552 | if (fstat(fd, &st) < 0) | |
1553 | return -errno; | |
1554 | ||
1555 | r = stat_verify_regular(&st); | |
1556 | if (r < 0) | |
1557 | return r; | |
1558 | ||
1559 | r = dissected_image_new(path, &m); | |
1560 | if (r < 0) | |
1561 | return r; | |
1562 | ||
1563 | m->image_size = st.st_size; | |
1564 | ||
1565 | r = probe_sector_size(fd, &m->sector_size); | |
1566 | if (r < 0) | |
1567 | return r; | |
1568 | ||
1569 | r = dissect_image(m, fd, path, verity, mount_options, image_policy, flags); | |
1570 | if (r < 0) | |
1571 | return r; | |
1572 | ||
1573 | if (ret) | |
1574 | *ret = TAKE_PTR(m); | |
1575 | return 0; | |
1576 | #else | |
1577 | return -EOPNOTSUPP; | |
1578 | #endif | |
1579 | } | |
1580 | ||
1581 | int dissect_log_error(int log_level, int r, const char *name, const VeritySettings *verity) { | |
1582 | assert(log_level >= 0 && log_level <= LOG_DEBUG); | |
1583 | assert(name); | |
1584 | ||
1585 | switch (r) { | |
1586 | ||
1587 | case 0 ... INT_MAX: /* success! */ | |
1588 | return r; | |
1589 | ||
1590 | case -EOPNOTSUPP: | |
1591 | return log_full_errno(log_level, r, "Dissecting images is not supported, compiled without blkid support."); | |
1592 | ||
1593 | case -ENOPKG: | |
1594 | return log_full_errno(log_level, r, "%s: Couldn't identify a suitable partition table or file system.", name); | |
1595 | ||
1596 | case -ENOMEDIUM: | |
1597 | return log_full_errno(log_level, r, "%s: The image does not pass os-release/extension-release validation.", name); | |
1598 | ||
1599 | case -EADDRNOTAVAIL: | |
1600 | return log_full_errno(log_level, r, "%s: No root partition for specified root hash found.", name); | |
1601 | ||
1602 | case -ENOTUNIQ: | |
1603 | return log_full_errno(log_level, r, "%s: Multiple suitable root partitions found in image.", name); | |
1604 | ||
1605 | case -ENXIO: | |
1606 | return log_full_errno(log_level, r, "%s: No suitable root partition found in image.", name); | |
1607 | ||
1608 | case -EPROTONOSUPPORT: | |
1609 | return log_full_errno(log_level, r, "Device '%s' is a loopback block device with partition scanning turned off, please turn it on.", name); | |
1610 | ||
1611 | case -ENOTBLK: | |
1612 | return log_full_errno(log_level, r, "%s: Image is not a block device.", name); | |
1613 | ||
1614 | case -EBADR: | |
1615 | return log_full_errno(log_level, r, | |
1616 | "Combining partitioned images (such as '%s') with external Verity data (such as '%s') not supported. " | |
1617 | "(Consider setting $SYSTEMD_DISSECT_VERITY_SIDECAR=0 to disable automatic discovery of external Verity data.)", | |
1618 | name, strna(verity ? verity->data_path : NULL)); | |
1619 | ||
1620 | case -ERFKILL: | |
1621 | return log_full_errno(log_level, r, "%s: image does not match image policy.", name); | |
1622 | ||
1623 | case -ENOMSG: | |
1624 | return log_full_errno(log_level, r, "%s: no suitable partitions found.", name); | |
1625 | ||
1626 | default: | |
1627 | return log_full_errno(log_level, r, "%s: cannot dissect image: %m", name); | |
1628 | } | |
1629 | } | |
1630 | ||
1631 | int dissect_image_file_and_warn( | |
1632 | const char *path, | |
1633 | const VeritySettings *verity, | |
1634 | const MountOptions *mount_options, | |
1635 | const ImagePolicy *image_policy, | |
1636 | DissectImageFlags flags, | |
1637 | DissectedImage **ret) { | |
1638 | ||
1639 | return dissect_log_error( | |
1640 | LOG_ERR, | |
1641 | dissect_image_file(path, verity, mount_options, image_policy, flags, ret), | |
1642 | path, | |
1643 | verity); | |
1644 | } | |
1645 | ||
1646 | DissectedImage* dissected_image_unref(DissectedImage *m) { | |
1647 | if (!m) | |
1648 | return NULL; | |
1649 | ||
1650 | /* First, clear dissected partitions. */ | |
1651 | for (PartitionDesignator i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) | |
1652 | dissected_partition_done(m->partitions + i); | |
1653 | ||
1654 | /* Second, free decrypted images. This must be after dissected_partition_done(), as freeing | |
1655 | * DecryptedImage may try to deactivate partitions. */ | |
1656 | decrypted_image_unref(m->decrypted_image); | |
1657 | ||
1658 | /* Third, unref LoopDevice. This must be called after the above two, as freeing LoopDevice may try to | |
1659 | * remove existing partitions on the loopback block device. */ | |
1660 | loop_device_unref(m->loop); | |
1661 | ||
1662 | free(m->image_name); | |
1663 | free(m->hostname); | |
1664 | strv_free(m->machine_info); | |
1665 | strv_free(m->os_release); | |
1666 | strv_free(m->initrd_release); | |
1667 | strv_free(m->confext_release); | |
1668 | strv_free(m->sysext_release); | |
1669 | ||
1670 | return mfree(m); | |
1671 | } | |
1672 | ||
1673 | static int is_loop_device(const char *path) { | |
1674 | char s[SYS_BLOCK_PATH_MAX("/../loop/")]; | |
1675 | struct stat st; | |
1676 | ||
1677 | assert(path); | |
1678 | ||
1679 | if (stat(path, &st) < 0) | |
1680 | return -errno; | |
1681 | ||
1682 | if (!S_ISBLK(st.st_mode)) | |
1683 | return -ENOTBLK; | |
1684 | ||
1685 | xsprintf_sys_block_path(s, "/loop/", st.st_dev); | |
1686 | if (access(s, F_OK) < 0) { | |
1687 | if (errno != ENOENT) | |
1688 | return -errno; | |
1689 | ||
1690 | /* The device itself isn't a loop device, but maybe it's a partition and its parent is? */ | |
1691 | xsprintf_sys_block_path(s, "/../loop/", st.st_dev); | |
1692 | if (access(s, F_OK) < 0) | |
1693 | return errno == ENOENT ? false : -errno; | |
1694 | } | |
1695 | ||
1696 | return true; | |
1697 | } | |
1698 | ||
1699 | static int run_fsck(int node_fd, const char *fstype) { | |
1700 | int r, exit_status; | |
1701 | pid_t pid; | |
1702 | ||
1703 | assert(node_fd >= 0); | |
1704 | assert(fstype); | |
1705 | ||
1706 | r = fsck_exists_for_fstype(fstype); | |
1707 | if (r < 0) { | |
1708 | log_debug_errno(r, "Couldn't determine whether fsck for %s exists, proceeding anyway.", fstype); | |
1709 | return 0; | |
1710 | } | |
1711 | if (r == 0) { | |
1712 | log_debug("Not checking partition %s, as fsck for %s does not exist.", FORMAT_PROC_FD_PATH(node_fd), fstype); | |
1713 | return 0; | |
1714 | } | |
1715 | ||
1716 | r = safe_fork_full( | |
1717 | "(fsck)", | |
1718 | NULL, | |
1719 | &node_fd, 1, /* Leave the node fd open */ | |
1720 | FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_DEATHSIG_SIGTERM|FORK_REARRANGE_STDIO|FORK_CLOEXEC_OFF, | |
1721 | &pid); | |
1722 | if (r < 0) | |
1723 | return log_debug_errno(r, "Failed to fork off fsck: %m"); | |
1724 | if (r == 0) { | |
1725 | /* Child */ | |
1726 | execlp("fsck", "fsck", "-aT", FORMAT_PROC_FD_PATH(node_fd), NULL); | |
1727 | log_open(); | |
1728 | log_debug_errno(errno, "Failed to execl() fsck: %m"); | |
1729 | _exit(FSCK_OPERATIONAL_ERROR); | |
1730 | } | |
1731 | ||
1732 | exit_status = wait_for_terminate_and_check("fsck", pid, 0); | |
1733 | if (exit_status < 0) | |
1734 | return log_debug_errno(exit_status, "Failed to fork off fsck: %m"); | |
1735 | ||
1736 | if ((exit_status & ~FSCK_ERROR_CORRECTED) != FSCK_SUCCESS) { | |
1737 | log_debug("fsck failed with exit status %i.", exit_status); | |
1738 | ||
1739 | if ((exit_status & (FSCK_SYSTEM_SHOULD_REBOOT|FSCK_ERRORS_LEFT_UNCORRECTED)) != 0) | |
1740 | return log_debug_errno(SYNTHETIC_ERRNO(EUCLEAN), "File system is corrupted, refusing."); | |
1741 | ||
1742 | log_debug("Ignoring fsck error."); | |
1743 | } | |
1744 | ||
1745 | return 0; | |
1746 | } | |
1747 | ||
1748 | static int fs_grow(const char *node_path, int mount_fd, const char *mount_path) { | |
1749 | _cleanup_close_ int _mount_fd = -EBADF, node_fd = -EBADF; | |
1750 | uint64_t size, newsize; | |
1751 | const char *id; | |
1752 | int r; | |
1753 | ||
1754 | assert(node_path); | |
1755 | assert(mount_fd >= 0 || mount_path); | |
1756 | ||
1757 | node_fd = open(node_path, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); | |
1758 | if (node_fd < 0) | |
1759 | return log_debug_errno(errno, "Failed to open node device %s: %m", node_path); | |
1760 | ||
1761 | r = blockdev_get_device_size(node_fd, &size); | |
1762 | if (r < 0) | |
1763 | return log_debug_errno(r, "Failed to get block device size of %s: %m", node_path); | |
1764 | ||
1765 | if (mount_fd < 0) { | |
1766 | assert(mount_path); | |
1767 | ||
1768 | _mount_fd = open(mount_path, O_RDONLY|O_DIRECTORY|O_CLOEXEC); | |
1769 | if (_mount_fd < 0) | |
1770 | return log_debug_errno(errno, "Failed to open mounted file system %s: %m", mount_path); | |
1771 | ||
1772 | mount_fd = _mount_fd; | |
1773 | } else { | |
1774 | mount_fd = fd_reopen_condition(mount_fd, O_RDONLY|O_DIRECTORY|O_CLOEXEC, O_RDONLY|O_DIRECTORY|O_CLOEXEC, &_mount_fd); | |
1775 | if (mount_fd < 0) | |
1776 | return log_debug_errno(errno, "Failed to reopen mount node: %m"); | |
1777 | } | |
1778 | ||
1779 | id = mount_path ?: node_path; | |
1780 | ||
1781 | log_debug("Resizing \"%s\" to %"PRIu64" bytes...", id, size); | |
1782 | r = resize_fs(mount_fd, size, &newsize); | |
1783 | if (r < 0) | |
1784 | return log_debug_errno(r, "Failed to resize \"%s\" to %"PRIu64" bytes: %m", id, size); | |
1785 | ||
1786 | if (newsize == size) | |
1787 | log_debug("Successfully resized \"%s\" to %s bytes.", | |
1788 | id, FORMAT_BYTES(newsize)); | |
1789 | else { | |
1790 | assert(newsize < size); | |
1791 | log_debug("Successfully resized \"%s\" to %s bytes (%"PRIu64" bytes lost due to blocksize).", | |
1792 | id, FORMAT_BYTES(newsize), size - newsize); | |
1793 | } | |
1794 | ||
1795 | return 0; | |
1796 | } | |
1797 | ||
1798 | int partition_pick_mount_options( | |
1799 | PartitionDesignator d, | |
1800 | const char *fstype, | |
1801 | bool rw, | |
1802 | bool discard, | |
1803 | char **ret_options, | |
1804 | unsigned long *ret_ms_flags) { | |
1805 | ||
1806 | _cleanup_free_ char *options = NULL; | |
1807 | ||
1808 | assert(ret_options); | |
1809 | ||
1810 | /* Selects a baseline of bind mount flags, that should always apply. | |
1811 | * | |
1812 | * Firstly, we set MS_NODEV universally on all mounts, since we don't want to allow device nodes outside of /dev/. | |
1813 | * | |
1814 | * On /var/tmp/ we'll also set MS_NOSUID, same as we set for /tmp/ on the host. | |
1815 | * | |
1816 | * On the ESP and XBOOTLDR partitions we'll also disable symlinks, and execution. These file systems | |
1817 | * are generally untrusted (i.e. not encrypted or authenticated), and typically VFAT hence we should | |
1818 | * be as restrictive as possible, and this shouldn't hurt, since the functionality is not available | |
1819 | * there anyway. */ | |
1820 | ||
1821 | unsigned long flags = MS_NODEV; | |
1822 | ||
1823 | if (!rw) | |
1824 | flags |= MS_RDONLY; | |
1825 | ||
1826 | switch (d) { | |
1827 | ||
1828 | case PARTITION_ESP: | |
1829 | case PARTITION_XBOOTLDR: | |
1830 | flags |= MS_NOSUID|MS_NOEXEC|ms_nosymfollow_supported(); | |
1831 | ||
1832 | /* The ESP might contain a pre-boot random seed. Let's make this unaccessible to regular | |
1833 | * userspace. ESP/XBOOTLDR is almost certainly VFAT, hence if we don't know assume it is. */ | |
1834 | if (!fstype || fstype_can_umask(fstype)) | |
1835 | if (!strextend_with_separator(&options, ",", "umask=0077")) | |
1836 | return -ENOMEM; | |
1837 | break; | |
1838 | ||
1839 | case PARTITION_TMP: | |
1840 | flags |= MS_NOSUID; | |
1841 | break; | |
1842 | ||
1843 | default: | |
1844 | break; | |
1845 | } | |
1846 | ||
1847 | /* So, when you request MS_RDONLY from ext4, then this means nothing. It happily still writes to the | |
1848 | * backing storage. What's worse, the BLKRO[GS]ET flag and (in case of loopback devices) | |
1849 | * LO_FLAGS_READ_ONLY don't mean anything, they affect userspace accesses only, and write accesses | |
1850 | * from the upper file system still get propagated through to the underlying file system, | |
1851 | * unrestricted. To actually get ext4/xfs/btrfs to stop writing to the device we need to specify | |
1852 | * "norecovery" as mount option, in addition to MS_RDONLY. Yes, this sucks, since it means we need to | |
1853 | * carry a per file system table here. | |
1854 | * | |
1855 | * Note that this means that we might not be able to mount corrupted file systems as read-only | |
1856 | * anymore (since in some cases the kernel implementations will refuse mounting when corrupted, | |
1857 | * read-only and "norecovery" is specified). But I think for the case of automatically determined | |
1858 | * mount options for loopback devices this is the right choice, since otherwise using the same | |
1859 | * loopback file twice even in read-only mode, is going to fail badly sooner or later. The use case of | |
1860 | * making reuse of the immutable images "just work" is more relevant to us than having read-only | |
1861 | * access that actually modifies stuff work on such image files. Or to say this differently: if | |
1862 | * people want their file systems to be fixed up they should just open them in writable mode, where | |
1863 | * all these problems don't exist. */ | |
1864 | if (!rw && fstype && fstype_can_norecovery(fstype)) | |
1865 | if (!strextend_with_separator(&options, ",", "norecovery")) | |
1866 | return -ENOMEM; | |
1867 | ||
1868 | if (discard && fstype && fstype_can_discard(fstype)) | |
1869 | if (!strextend_with_separator(&options, ",", "discard")) | |
1870 | return -ENOMEM; | |
1871 | ||
1872 | if (!ret_ms_flags) /* Fold flags into option string if ret_flags specified as NULL */ | |
1873 | if (!strextend_with_separator(&options, ",", | |
1874 | FLAGS_SET(flags, MS_RDONLY) ? "ro" : "rw", | |
1875 | FLAGS_SET(flags, MS_NODEV) ? "nodev" : "dev", | |
1876 | FLAGS_SET(flags, MS_NOSUID) ? "nosuid" : "suid", | |
1877 | FLAGS_SET(flags, MS_NOEXEC) ? "noexec" : "exec", | |
1878 | FLAGS_SET(flags, MS_NOSYMFOLLOW) ? "nosymfollow" : NULL)) | |
1879 | /* NB: we suppress 'symfollow' here, since it's the default, and old /bin/mount might not know it */ | |
1880 | return -ENOMEM; | |
1881 | ||
1882 | if (ret_ms_flags) | |
1883 | *ret_ms_flags = flags; | |
1884 | ||
1885 | *ret_options = TAKE_PTR(options); | |
1886 | return 0; | |
1887 | } | |
1888 | ||
1889 | static bool need_user_mapping(uid_t uid_shift, uid_t uid_range) { | |
1890 | ||
1891 | if (!uid_is_valid(uid_shift)) | |
1892 | return false; | |
1893 | ||
1894 | return uid_shift != 0 || uid_range != UINT32_MAX; | |
1895 | } | |
1896 | ||
1897 | static int mount_partition( | |
1898 | PartitionDesignator d, | |
1899 | DissectedPartition *m, | |
1900 | const char *where, | |
1901 | const char *directory, | |
1902 | uid_t uid_shift, | |
1903 | uid_t uid_range, | |
1904 | int userns_fd, | |
1905 | DissectImageFlags flags) { | |
1906 | ||
1907 | _cleanup_free_ char *chased = NULL, *options = NULL; | |
1908 | const char *p = NULL, *node, *fstype = NULL; | |
1909 | bool rw, discard, grow; | |
1910 | unsigned long ms_flags; | |
1911 | int r; | |
1912 | ||
1913 | assert(m); | |
1914 | ||
1915 | if (!m->found) | |
1916 | return 0; | |
1917 | ||
1918 | /* Check the various combinations when we can't do anything anymore */ | |
1919 | if (m->fsmount_fd < 0 && m->mount_node_fd < 0) | |
1920 | return 0; | |
1921 | if (m->fsmount_fd >= 0 && !where) | |
1922 | return 0; | |
1923 | if (!where && m->mount_node_fd < 0) | |
1924 | return 0; | |
1925 | ||
1926 | if (m->fsmount_fd < 0) { | |
1927 | fstype = dissected_partition_fstype(m); | |
1928 | if (!fstype) | |
1929 | return -EAFNOSUPPORT; | |
1930 | ||
1931 | /* We are looking at an encrypted partition? This either means stacked encryption, or the | |
1932 | * caller didn't call dissected_image_decrypt() beforehand. Let's return a recognizable error | |
1933 | * for this case. */ | |
1934 | if (streq(fstype, "crypto_LUKS")) | |
1935 | return -EUNATCH; | |
1936 | ||
1937 | r = dissect_fstype_ok(fstype); | |
1938 | if (r < 0) | |
1939 | return r; | |
1940 | if (!r) | |
1941 | return -EIDRM; /* Recognizable error */ | |
1942 | } | |
1943 | ||
1944 | node = m->mount_node_fd < 0 ? NULL : FORMAT_PROC_FD_PATH(m->mount_node_fd); | |
1945 | rw = m->rw && !(flags & DISSECT_IMAGE_MOUNT_READ_ONLY); | |
1946 | ||
1947 | discard = ((flags & DISSECT_IMAGE_DISCARD) || | |
1948 | ((flags & DISSECT_IMAGE_DISCARD_ON_LOOP) && (m->node && is_loop_device(m->node) > 0))); | |
1949 | ||
1950 | grow = rw && m->growfs && FLAGS_SET(flags, DISSECT_IMAGE_GROWFS); | |
1951 | ||
1952 | if (FLAGS_SET(flags, DISSECT_IMAGE_FSCK) && rw && m->mount_node_fd >= 0 && m->fsmount_fd < 0) { | |
1953 | r = run_fsck(m->mount_node_fd, fstype); | |
1954 | if (r < 0) | |
1955 | return r; | |
1956 | } | |
1957 | ||
1958 | if (where) { | |
1959 | if (directory) { | |
1960 | /* Automatically create missing mount points inside the image, if necessary. */ | |
1961 | r = mkdir_p_root(where, directory, uid_shift, (gid_t) uid_shift, 0755, NULL); | |
1962 | if (r < 0 && r != -EROFS) | |
1963 | return r; | |
1964 | ||
1965 | r = chase(directory, where, CHASE_PREFIX_ROOT, &chased, NULL); | |
1966 | if (r < 0) | |
1967 | return r; | |
1968 | ||
1969 | p = chased; | |
1970 | } else { | |
1971 | /* Create top-level mount if missing – but only if this is asked for. This won't modify the | |
1972 | * image (as the branch above does) but the host hierarchy, and the created directory might | |
1973 | * survive our mount in the host hierarchy hence. */ | |
1974 | if (FLAGS_SET(flags, DISSECT_IMAGE_MKDIR)) { | |
1975 | r = mkdir_p(where, 0755); | |
1976 | if (r < 0) | |
1977 | return r; | |
1978 | } | |
1979 | ||
1980 | p = where; | |
1981 | } | |
1982 | } | |
1983 | ||
1984 | if (m->fsmount_fd < 0) { | |
1985 | r = partition_pick_mount_options(d, fstype, rw, discard, &options, &ms_flags); | |
1986 | if (r < 0) | |
1987 | return r; | |
1988 | ||
1989 | if (need_user_mapping(uid_shift, uid_range) && fstype_can_uid_gid(fstype)) { | |
1990 | _cleanup_free_ char *uid_option = NULL; | |
1991 | ||
1992 | if (asprintf(&uid_option, "uid=" UID_FMT ",gid=" GID_FMT, uid_shift, (gid_t) uid_shift) < 0) | |
1993 | return -ENOMEM; | |
1994 | ||
1995 | if (!strextend_with_separator(&options, ",", uid_option)) | |
1996 | return -ENOMEM; | |
1997 | ||
1998 | userns_fd = -EBADF; /* Not needed */ | |
1999 | } | |
2000 | ||
2001 | if (!isempty(m->mount_options)) | |
2002 | if (!strextend_with_separator(&options, ",", m->mount_options)) | |
2003 | return -ENOMEM; | |
2004 | } | |
2005 | ||
2006 | if (p) { | |
2007 | if (m->fsmount_fd >= 0) { | |
2008 | /* Case #1: Attach existing fsmount fd to the file system */ | |
2009 | ||
2010 | r = mount_exchange_graceful( | |
2011 | m->fsmount_fd, | |
2012 | p, | |
2013 | FLAGS_SET(flags, DISSECT_IMAGE_TRY_ATOMIC_MOUNT_EXCHANGE)); | |
2014 | if (r < 0) | |
2015 | return log_debug_errno(r, "Failed to mount image on '%s': %m", p); | |
2016 | ||
2017 | } else { | |
2018 | assert(node); | |
2019 | ||
2020 | /* Case #2: Mount directly into place */ | |
2021 | r = mount_nofollow_verbose(LOG_DEBUG, node, p, fstype, ms_flags, options); | |
2022 | if (r < 0) | |
2023 | return r; | |
2024 | ||
2025 | if (grow) | |
2026 | (void) fs_grow(node, -EBADF, p); | |
2027 | ||
2028 | if (userns_fd >= 0) { | |
2029 | r = remount_idmap_fd(STRV_MAKE(p), userns_fd); | |
2030 | if (r < 0) | |
2031 | return r; | |
2032 | } | |
2033 | } | |
2034 | } else { | |
2035 | assert(node); | |
2036 | ||
2037 | /* Case #3: Create fsmount fd */ | |
2038 | ||
2039 | m->fsmount_fd = make_fsmount(LOG_DEBUG, node, fstype, ms_flags, options, userns_fd); | |
2040 | if (m->fsmount_fd < 0) | |
2041 | return m->fsmount_fd; | |
2042 | ||
2043 | if (grow) | |
2044 | (void) fs_grow(node, m->fsmount_fd, NULL); | |
2045 | } | |
2046 | ||
2047 | return 1; | |
2048 | } | |
2049 | ||
2050 | static int mount_root_tmpfs(const char *where, uid_t uid_shift, uid_t uid_range, DissectImageFlags flags) { | |
2051 | _cleanup_free_ char *options = NULL; | |
2052 | int r; | |
2053 | ||
2054 | assert(where); | |
2055 | ||
2056 | /* For images that contain /usr/ but no rootfs, let's mount rootfs as tmpfs */ | |
2057 | ||
2058 | if (FLAGS_SET(flags, DISSECT_IMAGE_MKDIR)) { | |
2059 | r = mkdir_p(where, 0755); | |
2060 | if (r < 0) | |
2061 | return r; | |
2062 | } | |
2063 | ||
2064 | if (need_user_mapping(uid_shift, uid_range)) { | |
2065 | if (asprintf(&options, "uid=" UID_FMT ",gid=" GID_FMT, uid_shift, (gid_t) uid_shift) < 0) | |
2066 | return -ENOMEM; | |
2067 | } | |
2068 | ||
2069 | r = mount_nofollow_verbose(LOG_DEBUG, "rootfs", where, "tmpfs", MS_NODEV, options); | |
2070 | if (r < 0) | |
2071 | return r; | |
2072 | ||
2073 | return 1; | |
2074 | } | |
2075 | ||
2076 | static int mount_point_is_available(const char *where, const char *path, bool missing_ok) { | |
2077 | _cleanup_free_ char *p = NULL; | |
2078 | int r; | |
2079 | ||
2080 | /* Check whether <path> is suitable as a mountpoint, i.e. is an empty directory | |
2081 | * or does not exist at all (when missing_ok). */ | |
2082 | ||
2083 | r = chase(path, where, CHASE_PREFIX_ROOT, &p, NULL); | |
2084 | if (r == -ENOENT) | |
2085 | return missing_ok; | |
2086 | if (r < 0) | |
2087 | return log_debug_errno(r, "Failed to chase \"%s\": %m", path); | |
2088 | ||
2089 | r = dir_is_empty(p, /* ignore_hidden_or_backup= */ false); | |
2090 | if (r == -ENOTDIR) | |
2091 | return false; | |
2092 | if (r < 0) | |
2093 | return log_debug_errno(r, "Failed to check directory \"%s\": %m", p); | |
2094 | return r > 0; | |
2095 | } | |
2096 | ||
2097 | int dissected_image_mount( | |
2098 | DissectedImage *m, | |
2099 | const char *where, | |
2100 | uid_t uid_shift, | |
2101 | uid_t uid_range, | |
2102 | int userns_fd, | |
2103 | DissectImageFlags flags) { | |
2104 | ||
2105 | _cleanup_close_ int my_userns_fd = -EBADF; | |
2106 | int r; | |
2107 | ||
2108 | assert(m); | |
2109 | ||
2110 | /* If 'where' is NULL then we'll use the new mount API to create fsmount() fds for the mounts and | |
2111 | * store them in DissectedPartition.fsmount_fd. | |
2112 | * | |
2113 | * If 'where' is not NULL then we'll either mount the partitions to the right places ourselves, | |
2114 | * or use DissectedPartition.fsmount_fd and bind it to the right places. | |
2115 | * | |
2116 | * This allows splitting the setting up up the superblocks and the binding to file systems paths into | |
2117 | * two distinct and differently privileged components: one that gets the fsmount fds, and the other | |
2118 | * that then applies them. | |
2119 | * | |
2120 | * Returns: | |
2121 | * | |
2122 | * -ENXIO → No root partition found | |
2123 | * -EMEDIUMTYPE → DISSECT_IMAGE_VALIDATE_OS set but no os-release/extension-release file found | |
2124 | * -EUNATCH → Encrypted partition found for which no dm-crypt was set up yet | |
2125 | * -EUCLEAN → fsck for file system failed | |
2126 | * -EBUSY → File system already mounted/used elsewhere (kernel) | |
2127 | * -EAFNOSUPPORT → File system type not supported or not known | |
2128 | * -EIDRM → File system is not among allowlisted "common" file systems | |
2129 | */ | |
2130 | ||
2131 | if (!where && (flags & (DISSECT_IMAGE_VALIDATE_OS|DISSECT_IMAGE_VALIDATE_OS_EXT)) != 0) | |
2132 | return -EOPNOTSUPP; /* for now, not supported */ | |
2133 | ||
2134 | if (!(m->partitions[PARTITION_ROOT].found || | |
2135 | (m->partitions[PARTITION_USR].found && FLAGS_SET(flags, DISSECT_IMAGE_USR_NO_ROOT)))) | |
2136 | return -ENXIO; /* Require a root fs or at least a /usr/ fs (the latter is subject to a flag of its own) */ | |
2137 | ||
2138 | if (userns_fd < 0 && need_user_mapping(uid_shift, uid_range) && FLAGS_SET(flags, DISSECT_IMAGE_MOUNT_IDMAPPED)) { | |
2139 | ||
2140 | my_userns_fd = make_userns(uid_shift, uid_range, UID_INVALID, UID_INVALID, REMOUNT_IDMAPPING_HOST_ROOT); | |
2141 | if (my_userns_fd < 0) | |
2142 | return my_userns_fd; | |
2143 | ||
2144 | userns_fd = my_userns_fd; | |
2145 | } | |
2146 | ||
2147 | if ((flags & DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY) == 0) { | |
2148 | ||
2149 | /* First mount the root fs. If there's none we use a tmpfs. */ | |
2150 | if (m->partitions[PARTITION_ROOT].found) { | |
2151 | r = mount_partition(PARTITION_ROOT, m->partitions + PARTITION_ROOT, where, NULL, uid_shift, uid_range, userns_fd, flags); | |
2152 | if (r < 0) | |
2153 | return r; | |
2154 | ||
2155 | } else if (where) { | |
2156 | r = mount_root_tmpfs(where, uid_shift, uid_range, flags); | |
2157 | if (r < 0) | |
2158 | return r; | |
2159 | } | |
2160 | ||
2161 | /* For us mounting root always means mounting /usr as well */ | |
2162 | r = mount_partition(PARTITION_USR, m->partitions + PARTITION_USR, where, "/usr", uid_shift, uid_range, userns_fd, flags); | |
2163 | if (r < 0) | |
2164 | return r; | |
2165 | } | |
2166 | ||
2167 | if ((flags & DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY) == 0 && | |
2168 | (flags & (DISSECT_IMAGE_VALIDATE_OS|DISSECT_IMAGE_VALIDATE_OS_EXT)) != 0) { | |
2169 | /* If either one of the validation flags are set, ensure that the image qualifies as | |
2170 | * one or the other (or both). */ | |
2171 | bool ok = false; | |
2172 | ||
2173 | assert(where); | |
2174 | ||
2175 | if (FLAGS_SET(flags, DISSECT_IMAGE_VALIDATE_OS)) { | |
2176 | r = path_is_os_tree(where); | |
2177 | if (r < 0) | |
2178 | return r; | |
2179 | if (r > 0) | |
2180 | ok = true; | |
2181 | } | |
2182 | if (!ok && FLAGS_SET(flags, DISSECT_IMAGE_VALIDATE_OS_EXT) && m->image_name) { | |
2183 | r = extension_has_forbidden_content(where); | |
2184 | if (r < 0) | |
2185 | return r; | |
2186 | if (r == 0) { | |
2187 | r = path_is_extension_tree(IMAGE_SYSEXT, where, m->image_name, FLAGS_SET(flags, DISSECT_IMAGE_RELAX_EXTENSION_CHECK)); | |
2188 | if (r == 0) | |
2189 | r = path_is_extension_tree(IMAGE_CONFEXT, where, m->image_name, FLAGS_SET(flags, DISSECT_IMAGE_RELAX_EXTENSION_CHECK)); | |
2190 | if (r < 0) | |
2191 | return r; | |
2192 | if (r > 0) | |
2193 | ok = true; | |
2194 | } | |
2195 | } | |
2196 | ||
2197 | if (!ok) | |
2198 | return -ENOMEDIUM; | |
2199 | } | |
2200 | ||
2201 | if (flags & DISSECT_IMAGE_MOUNT_ROOT_ONLY) | |
2202 | return 0; | |
2203 | ||
2204 | r = mount_partition(PARTITION_HOME, m->partitions + PARTITION_HOME, where, "/home", uid_shift, uid_range, userns_fd, flags); | |
2205 | if (r < 0) | |
2206 | return r; | |
2207 | ||
2208 | r = mount_partition(PARTITION_SRV, m->partitions + PARTITION_SRV, where, "/srv", uid_shift, uid_range, userns_fd, flags); | |
2209 | if (r < 0) | |
2210 | return r; | |
2211 | ||
2212 | r = mount_partition(PARTITION_VAR, m->partitions + PARTITION_VAR, where, "/var", uid_shift, uid_range, userns_fd, flags); | |
2213 | if (r < 0) | |
2214 | return r; | |
2215 | ||
2216 | r = mount_partition(PARTITION_TMP, m->partitions + PARTITION_TMP, where, "/var/tmp", uid_shift, uid_range, userns_fd, flags); | |
2217 | if (r < 0) | |
2218 | return r; | |
2219 | ||
2220 | int slash_boot_is_available = 0; | |
2221 | if (where) { | |
2222 | r = slash_boot_is_available = mount_point_is_available(where, "/boot", /* missing_ok = */ true); | |
2223 | if (r < 0) | |
2224 | return r; | |
2225 | } | |
2226 | if (!where || slash_boot_is_available) { | |
2227 | r = mount_partition(PARTITION_XBOOTLDR, m->partitions + PARTITION_XBOOTLDR, where, "/boot", uid_shift, uid_range, userns_fd, flags); | |
2228 | if (r < 0) | |
2229 | return r; | |
2230 | slash_boot_is_available = !r; | |
2231 | } | |
2232 | ||
2233 | if (m->partitions[PARTITION_ESP].found) { | |
2234 | const char *esp_path = NULL; | |
2235 | ||
2236 | if (where) { | |
2237 | /* Mount the ESP to /boot/ if it exists and is empty and we didn't already mount the | |
2238 | * XBOOTLDR partition into it. Otherwise, use /efi instead, but only if it exists | |
2239 | * and is empty. */ | |
2240 | ||
2241 | if (slash_boot_is_available) { | |
2242 | r = mount_point_is_available(where, "/boot", /* missing_ok = */ false); | |
2243 | if (r < 0) | |
2244 | return r; | |
2245 | if (r > 0) | |
2246 | esp_path = "/boot"; | |
2247 | } | |
2248 | ||
2249 | if (!esp_path) { | |
2250 | r = mount_point_is_available(where, "/efi", /* missing_ok = */ true); | |
2251 | if (r < 0) | |
2252 | return r; | |
2253 | if (r > 0) | |
2254 | esp_path = "/efi"; | |
2255 | } | |
2256 | } | |
2257 | ||
2258 | /* OK, let's mount the ESP now (possibly creating the dir if missing) */ | |
2259 | r = mount_partition(PARTITION_ESP, m->partitions + PARTITION_ESP, where, esp_path, uid_shift, uid_range, userns_fd, flags); | |
2260 | if (r < 0) | |
2261 | return r; | |
2262 | } | |
2263 | ||
2264 | return 0; | |
2265 | } | |
2266 | ||
2267 | int dissected_image_mount_and_warn( | |
2268 | DissectedImage *m, | |
2269 | const char *where, | |
2270 | uid_t uid_shift, | |
2271 | uid_t uid_range, | |
2272 | int userns_fd, | |
2273 | DissectImageFlags flags) { | |
2274 | ||
2275 | int r; | |
2276 | ||
2277 | assert(m); | |
2278 | ||
2279 | r = dissected_image_mount(m, where, uid_shift, uid_range, userns_fd, flags); | |
2280 | if (r == -ENXIO) | |
2281 | return log_error_errno(r, "Failed to mount image: No root file system found in image."); | |
2282 | if (r == -EMEDIUMTYPE) | |
2283 | return log_error_errno(r, "Failed to mount image: No suitable os-release/extension-release file in image found."); | |
2284 | if (r == -EUNATCH) | |
2285 | return log_error_errno(r, "Failed to mount image: Encrypted file system discovered, but decryption not requested."); | |
2286 | if (r == -EUCLEAN) | |
2287 | return log_error_errno(r, "Failed to mount image: File system check on image failed."); | |
2288 | if (r == -EBUSY) | |
2289 | return log_error_errno(r, "Failed to mount image: File system already mounted elsewhere."); | |
2290 | if (r == -EAFNOSUPPORT) | |
2291 | return log_error_errno(r, "Failed to mount image: File system type not supported or not known."); | |
2292 | if (r == -EIDRM) | |
2293 | return log_error_errno(r, "Failed to mount image: File system is too uncommon, refused."); | |
2294 | if (r < 0) | |
2295 | return log_error_errno(r, "Failed to mount image: %m"); | |
2296 | ||
2297 | return r; | |
2298 | } | |
2299 | ||
2300 | #if HAVE_LIBCRYPTSETUP | |
2301 | struct DecryptedPartition { | |
2302 | struct crypt_device *device; | |
2303 | char *name; | |
2304 | bool relinquished; | |
2305 | }; | |
2306 | #endif | |
2307 | ||
2308 | typedef struct DecryptedPartition DecryptedPartition; | |
2309 | ||
2310 | struct DecryptedImage { | |
2311 | unsigned n_ref; | |
2312 | DecryptedPartition *decrypted; | |
2313 | size_t n_decrypted; | |
2314 | }; | |
2315 | ||
2316 | static DecryptedImage* decrypted_image_free(DecryptedImage *d) { | |
2317 | #if HAVE_LIBCRYPTSETUP | |
2318 | int r; | |
2319 | ||
2320 | if (!d) | |
2321 | return NULL; | |
2322 | ||
2323 | for (size_t i = 0; i < d->n_decrypted; i++) { | |
2324 | DecryptedPartition *p = d->decrypted + i; | |
2325 | ||
2326 | if (p->device && p->name && !p->relinquished) { | |
2327 | _cleanup_free_ char *node = NULL; | |
2328 | ||
2329 | node = path_join("/dev/mapper", p->name); | |
2330 | if (node) { | |
2331 | r = btrfs_forget_device(node); | |
2332 | if (r < 0 && r != -ENOENT) | |
2333 | log_debug_errno(r, "Failed to forget btrfs device %s, ignoring: %m", node); | |
2334 | } else | |
2335 | log_oom_debug(); | |
2336 | ||
2337 | /* Let's deactivate lazily, as the dm volume may be already/still used by other processes. */ | |
2338 | r = sym_crypt_deactivate_by_name(p->device, p->name, CRYPT_DEACTIVATE_DEFERRED); | |
2339 | if (r < 0) | |
2340 | log_debug_errno(r, "Failed to deactivate encrypted partition %s", p->name); | |
2341 | } | |
2342 | ||
2343 | if (p->device) | |
2344 | sym_crypt_free(p->device); | |
2345 | free(p->name); | |
2346 | } | |
2347 | ||
2348 | free(d->decrypted); | |
2349 | free(d); | |
2350 | #endif | |
2351 | return NULL; | |
2352 | } | |
2353 | ||
2354 | DEFINE_TRIVIAL_REF_UNREF_FUNC(DecryptedImage, decrypted_image, decrypted_image_free); | |
2355 | ||
2356 | #if HAVE_LIBCRYPTSETUP | |
2357 | static int decrypted_image_new(DecryptedImage **ret) { | |
2358 | _cleanup_(decrypted_image_unrefp) DecryptedImage *d = NULL; | |
2359 | ||
2360 | assert(ret); | |
2361 | ||
2362 | d = new(DecryptedImage, 1); | |
2363 | if (!d) | |
2364 | return -ENOMEM; | |
2365 | ||
2366 | *d = (DecryptedImage) { | |
2367 | .n_ref = 1, | |
2368 | }; | |
2369 | ||
2370 | *ret = TAKE_PTR(d); | |
2371 | return 0; | |
2372 | } | |
2373 | ||
2374 | static int make_dm_name_and_node(const void *original_node, const char *suffix, char **ret_name, char **ret_node) { | |
2375 | _cleanup_free_ char *name = NULL, *node = NULL; | |
2376 | const char *base; | |
2377 | ||
2378 | assert(original_node); | |
2379 | assert(suffix); | |
2380 | assert(ret_name); | |
2381 | assert(ret_node); | |
2382 | ||
2383 | base = strrchr(original_node, '/'); | |
2384 | if (!base) | |
2385 | base = original_node; | |
2386 | else | |
2387 | base++; | |
2388 | if (isempty(base)) | |
2389 | return -EINVAL; | |
2390 | ||
2391 | name = strjoin(base, suffix); | |
2392 | if (!name) | |
2393 | return -ENOMEM; | |
2394 | if (!filename_is_valid(name)) | |
2395 | return -EINVAL; | |
2396 | ||
2397 | node = path_join(sym_crypt_get_dir(), name); | |
2398 | if (!node) | |
2399 | return -ENOMEM; | |
2400 | ||
2401 | *ret_name = TAKE_PTR(name); | |
2402 | *ret_node = TAKE_PTR(node); | |
2403 | ||
2404 | return 0; | |
2405 | } | |
2406 | ||
2407 | static int decrypt_partition( | |
2408 | DissectedPartition *m, | |
2409 | const char *passphrase, | |
2410 | DissectImageFlags flags, | |
2411 | DecryptedImage *d) { | |
2412 | ||
2413 | _cleanup_free_ char *node = NULL, *name = NULL; | |
2414 | _cleanup_(sym_crypt_freep) struct crypt_device *cd = NULL; | |
2415 | _cleanup_close_ int fd = -EBADF; | |
2416 | int r; | |
2417 | ||
2418 | assert(m); | |
2419 | assert(d); | |
2420 | ||
2421 | if (!m->found || !m->node || !m->fstype) | |
2422 | return 0; | |
2423 | ||
2424 | if (!streq(m->fstype, "crypto_LUKS")) | |
2425 | return 0; | |
2426 | ||
2427 | if (!passphrase) | |
2428 | return -ENOKEY; | |
2429 | ||
2430 | r = dlopen_cryptsetup(); | |
2431 | if (r < 0) | |
2432 | return r; | |
2433 | ||
2434 | r = make_dm_name_and_node(m->node, "-decrypted", &name, &node); | |
2435 | if (r < 0) | |
2436 | return r; | |
2437 | ||
2438 | if (!GREEDY_REALLOC0(d->decrypted, d->n_decrypted + 1)) | |
2439 | return -ENOMEM; | |
2440 | ||
2441 | r = sym_crypt_init(&cd, m->node); | |
2442 | if (r < 0) | |
2443 | return log_debug_errno(r, "Failed to initialize dm-crypt: %m"); | |
2444 | ||
2445 | cryptsetup_enable_logging(cd); | |
2446 | ||
2447 | r = sym_crypt_load(cd, CRYPT_LUKS, NULL); | |
2448 | if (r < 0) | |
2449 | return log_debug_errno(r, "Failed to load LUKS metadata: %m"); | |
2450 | ||
2451 | r = sym_crypt_activate_by_passphrase(cd, name, CRYPT_ANY_SLOT, passphrase, strlen(passphrase), | |
2452 | ((flags & DISSECT_IMAGE_DEVICE_READ_ONLY) ? CRYPT_ACTIVATE_READONLY : 0) | | |
2453 | ((flags & DISSECT_IMAGE_DISCARD_ON_CRYPTO) ? CRYPT_ACTIVATE_ALLOW_DISCARDS : 0)); | |
2454 | if (r < 0) { | |
2455 | log_debug_errno(r, "Failed to activate LUKS device: %m"); | |
2456 | return r == -EPERM ? -EKEYREJECTED : r; | |
2457 | } | |
2458 | ||
2459 | fd = open(node, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); | |
2460 | if (fd < 0) | |
2461 | return log_debug_errno(errno, "Failed to open %s: %m", node); | |
2462 | ||
2463 | d->decrypted[d->n_decrypted++] = (DecryptedPartition) { | |
2464 | .name = TAKE_PTR(name), | |
2465 | .device = TAKE_PTR(cd), | |
2466 | }; | |
2467 | ||
2468 | m->decrypted_node = TAKE_PTR(node); | |
2469 | close_and_replace(m->mount_node_fd, fd); | |
2470 | ||
2471 | return 0; | |
2472 | } | |
2473 | ||
2474 | static int verity_can_reuse( | |
2475 | const VeritySettings *verity, | |
2476 | const char *name, | |
2477 | struct crypt_device **ret_cd) { | |
2478 | ||
2479 | /* If the same volume was already open, check that the root hashes match, and reuse it if they do */ | |
2480 | _cleanup_free_ char *root_hash_existing = NULL; | |
2481 | _cleanup_(sym_crypt_freep) struct crypt_device *cd = NULL; | |
2482 | struct crypt_params_verity crypt_params = {}; | |
2483 | size_t root_hash_existing_size; | |
2484 | int r; | |
2485 | ||
2486 | assert(verity); | |
2487 | assert(name); | |
2488 | assert(ret_cd); | |
2489 | ||
2490 | r = sym_crypt_init_by_name(&cd, name); | |
2491 | if (r < 0) | |
2492 | return log_debug_errno(r, "Error opening verity device, crypt_init_by_name failed: %m"); | |
2493 | ||
2494 | cryptsetup_enable_logging(cd); | |
2495 | ||
2496 | r = sym_crypt_get_verity_info(cd, &crypt_params); | |
2497 | if (r < 0) | |
2498 | return log_debug_errno(r, "Error opening verity device, crypt_get_verity_info failed: %m"); | |
2499 | ||
2500 | root_hash_existing_size = verity->root_hash_size; | |
2501 | root_hash_existing = malloc0(root_hash_existing_size); | |
2502 | if (!root_hash_existing) | |
2503 | return -ENOMEM; | |
2504 | ||
2505 | r = sym_crypt_volume_key_get(cd, CRYPT_ANY_SLOT, root_hash_existing, &root_hash_existing_size, NULL, 0); | |
2506 | if (r < 0) | |
2507 | return log_debug_errno(r, "Error opening verity device, crypt_volume_key_get failed: %m"); | |
2508 | if (verity->root_hash_size != root_hash_existing_size || | |
2509 | memcmp(root_hash_existing, verity->root_hash, verity->root_hash_size) != 0) | |
2510 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Error opening verity device, it already exists but root hashes are different."); | |
2511 | ||
2512 | #if HAVE_CRYPT_ACTIVATE_BY_SIGNED_KEY | |
2513 | /* Ensure that, if signatures are supported, we only reuse the device if the previous mount used the | |
2514 | * same settings, so that a previous unsigned mount will not be reused if the user asks to use | |
2515 | * signing for the new one, and vice versa. */ | |
2516 | if (!!verity->root_hash_sig != !!(crypt_params.flags & CRYPT_VERITY_ROOT_HASH_SIGNATURE)) | |
2517 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Error opening verity device, it already exists but signature settings are not the same."); | |
2518 | #endif | |
2519 | ||
2520 | *ret_cd = TAKE_PTR(cd); | |
2521 | return 0; | |
2522 | } | |
2523 | ||
2524 | static char* dm_deferred_remove_clean(char *name) { | |
2525 | if (!name) | |
2526 | return NULL; | |
2527 | ||
2528 | (void) sym_crypt_deactivate_by_name(NULL, name, CRYPT_DEACTIVATE_DEFERRED); | |
2529 | return mfree(name); | |
2530 | } | |
2531 | DEFINE_TRIVIAL_CLEANUP_FUNC(char *, dm_deferred_remove_clean); | |
2532 | ||
2533 | static int validate_signature_userspace(const VeritySettings *verity, DissectImageFlags flags) { | |
2534 | int r; | |
2535 | ||
2536 | if (!FLAGS_SET(flags, DISSECT_IMAGE_ALLOW_USERSPACE_VERITY)) { | |
2537 | log_debug("Userspace dm-verity signature authentication disabled via flag."); | |
2538 | return 0; | |
2539 | } | |
2540 | ||
2541 | r = secure_getenv_bool("SYSTEMD_ALLOW_USERSPACE_VERITY"); | |
2542 | if (r < 0 && r != -ENXIO) { | |
2543 | log_debug_errno(r, "Failed to parse $SYSTEMD_ALLOW_USERSPACE_VERITY environment variable, refusing userspace dm-verity signature authentication."); | |
2544 | return 0; | |
2545 | } | |
2546 | if (!r) { | |
2547 | log_debug("Userspace dm-verity signature authentication disabled via $SYSTEMD_ALLOW_USERSPACE_VERITY environment variable."); | |
2548 | return 0; | |
2549 | } | |
2550 | ||
2551 | bool b; | |
2552 | r = proc_cmdline_get_bool("systemd.allow_userspace_verity", PROC_CMDLINE_TRUE_WHEN_MISSING, &b); | |
2553 | if (r < 0) { | |
2554 | log_debug_errno(r, "Failed to parse systemd.allow_userspace_verity= kernel command line option, refusing userspace dm-verity signature authentication."); | |
2555 | return 0; | |
2556 | } | |
2557 | if (!b) { | |
2558 | log_debug("Userspace dm-verity signature authentication disabled via systemd.allow_userspace_verity= kernel command line variable."); | |
2559 | return 0; | |
2560 | } | |
2561 | ||
2562 | #if HAVE_OPENSSL | |
2563 | _cleanup_(sk_X509_free_allp) STACK_OF(X509) *sk = NULL; | |
2564 | _cleanup_strv_free_ char **certs = NULL; | |
2565 | _cleanup_(PKCS7_freep) PKCS7 *p7 = NULL; | |
2566 | _cleanup_free_ char *s = NULL; | |
2567 | _cleanup_(BIO_freep) BIO *bio = NULL; /* 'bio' must be freed first, 's' second, hence keep this order | |
2568 | * of declaration in place, please */ | |
2569 | const unsigned char *d; | |
2570 | ||
2571 | assert(verity); | |
2572 | assert(verity->root_hash); | |
2573 | assert(verity->root_hash_sig); | |
2574 | ||
2575 | /* Because installing a signature certificate into the kernel chain is so messy, let's optionally do | |
2576 | * userspace validation. */ | |
2577 | ||
2578 | r = conf_files_list_nulstr(&certs, ".crt", NULL, CONF_FILES_REGULAR|CONF_FILES_FILTER_MASKED, CONF_PATHS_NULSTR("verity.d")); | |
2579 | if (r < 0) | |
2580 | return log_debug_errno(r, "Failed to enumerate certificates: %m"); | |
2581 | if (strv_isempty(certs)) { | |
2582 | log_debug("No userspace dm-verity certificates found."); | |
2583 | return 0; | |
2584 | } | |
2585 | ||
2586 | d = verity->root_hash_sig; | |
2587 | p7 = d2i_PKCS7(NULL, &d, (long) verity->root_hash_sig_size); | |
2588 | if (!p7) | |
2589 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to parse PKCS7 DER signature data."); | |
2590 | ||
2591 | s = hexmem(verity->root_hash, verity->root_hash_size); | |
2592 | if (!s) | |
2593 | return log_oom_debug(); | |
2594 | ||
2595 | bio = BIO_new_mem_buf(s, strlen(s)); | |
2596 | if (!bio) | |
2597 | return log_oom_debug(); | |
2598 | ||
2599 | sk = sk_X509_new_null(); | |
2600 | if (!sk) | |
2601 | return log_oom_debug(); | |
2602 | ||
2603 | STRV_FOREACH(i, certs) { | |
2604 | _cleanup_(X509_freep) X509 *c = NULL; | |
2605 | _cleanup_fclose_ FILE *f = NULL; | |
2606 | ||
2607 | f = fopen(*i, "re"); | |
2608 | if (!f) { | |
2609 | log_debug_errno(errno, "Failed to open '%s', ignoring: %m", *i); | |
2610 | continue; | |
2611 | } | |
2612 | ||
2613 | c = PEM_read_X509(f, NULL, NULL, NULL); | |
2614 | if (!c) { | |
2615 | log_debug("Failed to load X509 certificate '%s', ignoring.", *i); | |
2616 | continue; | |
2617 | } | |
2618 | ||
2619 | if (sk_X509_push(sk, c) == 0) | |
2620 | return log_oom_debug(); | |
2621 | ||
2622 | TAKE_PTR(c); | |
2623 | } | |
2624 | ||
2625 | r = PKCS7_verify(p7, sk, NULL, bio, NULL, PKCS7_NOINTERN|PKCS7_NOVERIFY); | |
2626 | if (r) | |
2627 | log_debug("Userspace PKCS#7 validation succeeded."); | |
2628 | else | |
2629 | log_debug("Userspace PKCS#7 validation failed: %s", ERR_error_string(ERR_get_error(), NULL)); | |
2630 | ||
2631 | return r; | |
2632 | #else | |
2633 | log_debug("Not doing client-side validation of dm-verity root hash signatures, OpenSSL support disabled."); | |
2634 | return 0; | |
2635 | #endif | |
2636 | } | |
2637 | ||
2638 | static int do_crypt_activate_verity( | |
2639 | struct crypt_device *cd, | |
2640 | const char *name, | |
2641 | const VeritySettings *verity, | |
2642 | DissectImageFlags flags) { | |
2643 | ||
2644 | bool check_signature; | |
2645 | int r, k; | |
2646 | ||
2647 | assert(cd); | |
2648 | assert(name); | |
2649 | assert(verity); | |
2650 | ||
2651 | if (verity->root_hash_sig) { | |
2652 | r = secure_getenv_bool("SYSTEMD_DISSECT_VERITY_SIGNATURE"); | |
2653 | if (r < 0 && r != -ENXIO) | |
2654 | log_debug_errno(r, "Failed to parse $SYSTEMD_DISSECT_VERITY_SIGNATURE"); | |
2655 | ||
2656 | check_signature = r != 0; | |
2657 | } else | |
2658 | check_signature = false; | |
2659 | ||
2660 | if (check_signature) { | |
2661 | ||
2662 | #if HAVE_CRYPT_ACTIVATE_BY_SIGNED_KEY | |
2663 | /* First, if we have support for signed keys in the kernel, then try that first. */ | |
2664 | r = sym_crypt_activate_by_signed_key( | |
2665 | cd, | |
2666 | name, | |
2667 | verity->root_hash, | |
2668 | verity->root_hash_size, | |
2669 | verity->root_hash_sig, | |
2670 | verity->root_hash_sig_size, | |
2671 | CRYPT_ACTIVATE_READONLY); | |
2672 | if (r >= 0) | |
2673 | return r; | |
2674 | ||
2675 | log_debug_errno(r, "Validation of dm-verity signature failed via the kernel, trying userspace validation instead: %m"); | |
2676 | #else | |
2677 | log_debug("Activation of verity device with signature requested, but not supported via the kernel by %s due to missing crypt_activate_by_signed_key(), trying userspace validation instead.", | |
2678 | program_invocation_short_name); | |
2679 | r = 0; /* Set for the propagation below */ | |
2680 | #endif | |
2681 | ||
2682 | /* So this didn't work via the kernel, then let's try userspace validation instead. If that | |
2683 | * works we'll try to activate without telling the kernel the signature. */ | |
2684 | ||
2685 | /* Preferably propagate the original kernel error, so that the fallback logic can work, | |
2686 | * as the device-mapper is finicky around concurrent activations of the same volume */ | |
2687 | k = validate_signature_userspace(verity, flags); | |
2688 | if (k < 0) | |
2689 | return r < 0 ? r : k; | |
2690 | if (k == 0) | |
2691 | return log_debug_errno(r < 0 ? r : SYNTHETIC_ERRNO(ENOKEY), | |
2692 | "Activation of signed Verity volume worked neither via the kernel nor in userspace, can't activate."); | |
2693 | } | |
2694 | ||
2695 | return sym_crypt_activate_by_volume_key( | |
2696 | cd, | |
2697 | name, | |
2698 | verity->root_hash, | |
2699 | verity->root_hash_size, | |
2700 | CRYPT_ACTIVATE_READONLY); | |
2701 | } | |
2702 | ||
2703 | static usec_t verity_timeout(void) { | |
2704 | usec_t t = 100 * USEC_PER_MSEC; | |
2705 | const char *e; | |
2706 | int r; | |
2707 | ||
2708 | /* On slower machines, like non-KVM vm, setting up device may take a long time. | |
2709 | * Let's make the timeout configurable. */ | |
2710 | ||
2711 | e = getenv("SYSTEMD_DISSECT_VERITY_TIMEOUT_SEC"); | |
2712 | if (!e) | |
2713 | return t; | |
2714 | ||
2715 | r = parse_sec(e, &t); | |
2716 | if (r < 0) | |
2717 | log_debug_errno(r, | |
2718 | "Failed to parse timeout specified in $SYSTEMD_DISSECT_VERITY_TIMEOUT_SEC, " | |
2719 | "using the default timeout (%s).", | |
2720 | FORMAT_TIMESPAN(t, USEC_PER_MSEC)); | |
2721 | ||
2722 | return t; | |
2723 | } | |
2724 | ||
2725 | static int verity_partition( | |
2726 | PartitionDesignator designator, | |
2727 | DissectedPartition *m, | |
2728 | DissectedPartition *v, | |
2729 | const VeritySettings *verity, | |
2730 | DissectImageFlags flags, | |
2731 | DecryptedImage *d) { | |
2732 | ||
2733 | _cleanup_(sym_crypt_freep) struct crypt_device *cd = NULL; | |
2734 | _cleanup_free_ char *node = NULL, *name = NULL; | |
2735 | _cleanup_close_ int mount_node_fd = -EBADF; | |
2736 | int r; | |
2737 | ||
2738 | assert(m); | |
2739 | assert(v || (verity && verity->data_path)); | |
2740 | ||
2741 | if (!verity || !verity->root_hash) | |
2742 | return 0; | |
2743 | if (!((verity->designator < 0 && designator == PARTITION_ROOT) || | |
2744 | (verity->designator == designator))) | |
2745 | return 0; | |
2746 | ||
2747 | if (!m->found || !m->node || !m->fstype) | |
2748 | return 0; | |
2749 | if (!verity->data_path) { | |
2750 | if (!v->found || !v->node || !v->fstype) | |
2751 | return 0; | |
2752 | ||
2753 | if (!streq(v->fstype, "DM_verity_hash")) | |
2754 | return 0; | |
2755 | } | |
2756 | ||
2757 | r = dlopen_cryptsetup(); | |
2758 | if (r < 0) | |
2759 | return r; | |
2760 | ||
2761 | if (FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) { | |
2762 | /* Use the roothash, which is unique per volume, as the device node name, so that it can be reused */ | |
2763 | _cleanup_free_ char *root_hash_encoded = NULL; | |
2764 | ||
2765 | root_hash_encoded = hexmem(verity->root_hash, verity->root_hash_size); | |
2766 | if (!root_hash_encoded) | |
2767 | return -ENOMEM; | |
2768 | ||
2769 | r = make_dm_name_and_node(root_hash_encoded, "-verity", &name, &node); | |
2770 | } else | |
2771 | r = make_dm_name_and_node(m->node, "-verity", &name, &node); | |
2772 | if (r < 0) | |
2773 | return r; | |
2774 | ||
2775 | r = sym_crypt_init(&cd, verity->data_path ?: v->node); | |
2776 | if (r < 0) | |
2777 | return r; | |
2778 | ||
2779 | cryptsetup_enable_logging(cd); | |
2780 | ||
2781 | r = sym_crypt_load(cd, CRYPT_VERITY, NULL); | |
2782 | if (r < 0) | |
2783 | return r; | |
2784 | ||
2785 | r = sym_crypt_set_data_device(cd, m->node); | |
2786 | if (r < 0) | |
2787 | return r; | |
2788 | ||
2789 | if (!GREEDY_REALLOC0(d->decrypted, d->n_decrypted + 1)) | |
2790 | return -ENOMEM; | |
2791 | ||
2792 | /* If activating fails because the device already exists, check the metadata and reuse it if it matches. | |
2793 | * In case of ENODEV/ENOENT, which can happen if another process is activating at the exact same time, | |
2794 | * retry a few times before giving up. */ | |
2795 | for (unsigned i = 0; i < N_DEVICE_NODE_LIST_ATTEMPTS; i++) { | |
2796 | _cleanup_(dm_deferred_remove_cleanp) char *restore_deferred_remove = NULL; | |
2797 | _cleanup_(sym_crypt_freep) struct crypt_device *existing_cd = NULL; | |
2798 | _cleanup_close_ int fd = -EBADF; | |
2799 | ||
2800 | /* First, check if the device already exists. */ | |
2801 | fd = open(node, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); | |
2802 | if (fd < 0 && !ERRNO_IS_DEVICE_ABSENT(errno)) | |
2803 | return log_debug_errno(errno, "Failed to open verity device %s: %m", node); | |
2804 | if (fd >= 0) | |
2805 | goto check; /* The device already exists. Let's check it. */ | |
2806 | ||
2807 | /* The symlink to the device node does not exist yet. Assume not activated, and let's activate it. */ | |
2808 | r = do_crypt_activate_verity(cd, name, verity, flags); | |
2809 | if (r >= 0) | |
2810 | goto try_open; /* The device is activated. Let's open it. */ | |
2811 | /* libdevmapper can return EINVAL when the device is already in the activation stage. | |
2812 | * There's no way to distinguish this situation from a genuine error due to invalid | |
2813 | * parameters, so immediately fall back to activating the device with a unique name. | |
2814 | * Improvements in libcrypsetup can ensure this never happens: | |
2815 | * https://gitlab.com/cryptsetup/cryptsetup/-/merge_requests/96 */ | |
2816 | if (r == -EINVAL && FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) | |
2817 | break; | |
2818 | /* Volume is being opened but not ready, crypt_init_by_name would fail, try to open again if | |
2819 | * sharing is enabled. */ | |
2820 | if (r == -ENODEV && FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) | |
2821 | goto try_again; | |
2822 | if (!IN_SET(r, | |
2823 | -EEXIST, /* Volume has already been opened and ready to be used. */ | |
2824 | -EBUSY /* Volume is being opened but not ready, crypt_init_by_name() can fetch details. */)) | |
2825 | return log_debug_errno(r, "Failed to activate verity device %s: %m", node); | |
2826 | ||
2827 | check: | |
2828 | /* To avoid races, disable automatic removal on umount while setting up the new device. Restore it on failure. */ | |
2829 | r = dm_deferred_remove_cancel(name); | |
2830 | /* -EBUSY and -ENXIO: the device has already been removed or being removed. We cannot | |
2831 | * use the device, try to open again. See target_message() in drivers/md/dm-ioctl.c | |
2832 | * and dm_cancel_deferred_remove() in drivers/md/dm.c */ | |
2833 | if (IN_SET(r, -EBUSY, -ENXIO)) | |
2834 | goto try_again; | |
2835 | if (r < 0) | |
2836 | return log_debug_errno(r, "Failed to disable automated deferred removal for verity device %s: %m", node); | |
2837 | ||
2838 | restore_deferred_remove = strdup(name); | |
2839 | if (!restore_deferred_remove) | |
2840 | return log_oom_debug(); | |
2841 | ||
2842 | r = verity_can_reuse(verity, name, &existing_cd); | |
2843 | /* Same as above, -EINVAL can randomly happen when it actually means -EEXIST */ | |
2844 | if (r == -EINVAL && FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) | |
2845 | break; | |
2846 | if (IN_SET(r, | |
2847 | -ENOENT, /* Removed?? */ | |
2848 | -EBUSY, /* Volume is being opened but not ready, crypt_init_by_name() can fetch details. */ | |
2849 | -ENODEV /* Volume is being opened but not ready, crypt_init_by_name() would fail, try to open again. */ )) | |
2850 | goto try_again; | |
2851 | if (r < 0) | |
2852 | return log_debug_errno(r, "Failed to check if existing verity device %s can be reused: %m", node); | |
2853 | ||
2854 | if (fd < 0) { | |
2855 | /* devmapper might say that the device exists, but the devlink might not yet have been | |
2856 | * created. Check and wait for the udev event in that case. */ | |
2857 | r = device_wait_for_devlink(node, "block", verity_timeout(), NULL); | |
2858 | /* Fallback to activation with a unique device if it's taking too long */ | |
2859 | if (r == -ETIMEDOUT && FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) | |
2860 | break; | |
2861 | if (r < 0) | |
2862 | return log_debug_errno(r, "Failed to wait device node symlink %s: %m", node); | |
2863 | } | |
2864 | ||
2865 | try_open: | |
2866 | if (fd < 0) { | |
2867 | /* Now, the device is activated and devlink is created. Let's open it. */ | |
2868 | fd = open(node, O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY); | |
2869 | if (fd < 0) { | |
2870 | if (!ERRNO_IS_DEVICE_ABSENT(errno)) | |
2871 | return log_debug_errno(errno, "Failed to open verity device %s: %m", node); | |
2872 | ||
2873 | /* The device has already been removed?? */ | |
2874 | goto try_again; | |
2875 | } | |
2876 | } | |
2877 | ||
2878 | /* Everything looks good and we'll be able to mount the device, so deferred remove will be re-enabled at that point. */ | |
2879 | restore_deferred_remove = mfree(restore_deferred_remove); | |
2880 | ||
2881 | mount_node_fd = TAKE_FD(fd); | |
2882 | if (existing_cd) | |
2883 | crypt_free_and_replace(cd, existing_cd); | |
2884 | ||
2885 | goto success; | |
2886 | ||
2887 | try_again: | |
2888 | /* Device is being removed by another process. Let's wait for a while. */ | |
2889 | (void) usleep_safe(2 * USEC_PER_MSEC); | |
2890 | } | |
2891 | ||
2892 | /* All trials failed or a conflicting verity device exists. Let's try to activate with a unique name. */ | |
2893 | if (FLAGS_SET(flags, DISSECT_IMAGE_VERITY_SHARE)) { | |
2894 | /* Before trying to activate with unique name, we need to free crypt_device object. | |
2895 | * Otherwise, we get error from libcryptsetup like the following: | |
2896 | * ------ | |
2897 | * systemd[1234]: Cannot use device /dev/loop5 which is in use (already mapped or mounted). | |
2898 | * ------ | |
2899 | */ | |
2900 | sym_crypt_free(cd); | |
2901 | cd = NULL; | |
2902 | return verity_partition(designator, m, v, verity, flags & ~DISSECT_IMAGE_VERITY_SHARE, d); | |
2903 | } | |
2904 | ||
2905 | return log_debug_errno(SYNTHETIC_ERRNO(EBUSY), "All attempts to activate verity device %s failed.", name); | |
2906 | ||
2907 | success: | |
2908 | d->decrypted[d->n_decrypted++] = (DecryptedPartition) { | |
2909 | .name = TAKE_PTR(name), | |
2910 | .device = TAKE_PTR(cd), | |
2911 | }; | |
2912 | ||
2913 | m->decrypted_node = TAKE_PTR(node); | |
2914 | close_and_replace(m->mount_node_fd, mount_node_fd); | |
2915 | ||
2916 | return 0; | |
2917 | } | |
2918 | #endif | |
2919 | ||
2920 | int dissected_image_decrypt( | |
2921 | DissectedImage *m, | |
2922 | const char *passphrase, | |
2923 | const VeritySettings *verity, | |
2924 | DissectImageFlags flags) { | |
2925 | ||
2926 | #if HAVE_LIBCRYPTSETUP | |
2927 | _cleanup_(decrypted_image_unrefp) DecryptedImage *d = NULL; | |
2928 | int r; | |
2929 | #endif | |
2930 | ||
2931 | assert(m); | |
2932 | assert(!verity || verity->root_hash || verity->root_hash_size == 0); | |
2933 | ||
2934 | /* Returns: | |
2935 | * | |
2936 | * = 0 → There was nothing to decrypt | |
2937 | * > 0 → Decrypted successfully | |
2938 | * -ENOKEY → There's something to decrypt but no key was supplied | |
2939 | * -EKEYREJECTED → Passed key was not correct | |
2940 | */ | |
2941 | ||
2942 | if (verity && verity->root_hash && verity->root_hash_size < sizeof(sd_id128_t)) | |
2943 | return -EINVAL; | |
2944 | ||
2945 | if (!m->encrypted && !m->verity_ready) | |
2946 | return 0; | |
2947 | ||
2948 | #if HAVE_LIBCRYPTSETUP | |
2949 | r = decrypted_image_new(&d); | |
2950 | if (r < 0) | |
2951 | return r; | |
2952 | ||
2953 | for (PartitionDesignator i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) { | |
2954 | DissectedPartition *p = m->partitions + i; | |
2955 | PartitionDesignator k; | |
2956 | ||
2957 | if (!p->found) | |
2958 | continue; | |
2959 | ||
2960 | r = decrypt_partition(p, passphrase, flags, d); | |
2961 | if (r < 0) | |
2962 | return r; | |
2963 | ||
2964 | k = partition_verity_of(i); | |
2965 | if (k >= 0) { | |
2966 | flags |= getenv_bool("SYSTEMD_VERITY_SHARING") != 0 ? DISSECT_IMAGE_VERITY_SHARE : 0; | |
2967 | ||
2968 | r = verity_partition(i, p, m->partitions + k, verity, flags, d); | |
2969 | if (r < 0) | |
2970 | return r; | |
2971 | } | |
2972 | ||
2973 | if (!p->decrypted_fstype && p->mount_node_fd >= 0 && p->decrypted_node) { | |
2974 | r = probe_filesystem_full(p->mount_node_fd, p->decrypted_node, 0, UINT64_MAX, &p->decrypted_fstype); | |
2975 | if (r < 0 && r != -EUCLEAN) | |
2976 | return r; | |
2977 | } | |
2978 | } | |
2979 | ||
2980 | m->decrypted_image = TAKE_PTR(d); | |
2981 | ||
2982 | return 1; | |
2983 | #else | |
2984 | return -EOPNOTSUPP; | |
2985 | #endif | |
2986 | } | |
2987 | ||
2988 | int dissected_image_decrypt_interactively( | |
2989 | DissectedImage *m, | |
2990 | const char *passphrase, | |
2991 | const VeritySettings *verity, | |
2992 | DissectImageFlags flags) { | |
2993 | ||
2994 | _cleanup_strv_free_erase_ char **z = NULL; | |
2995 | int n = 3, r; | |
2996 | ||
2997 | if (passphrase) | |
2998 | n--; | |
2999 | ||
3000 | for (;;) { | |
3001 | r = dissected_image_decrypt(m, passphrase, verity, flags); | |
3002 | if (r >= 0) | |
3003 | return r; | |
3004 | if (r == -EKEYREJECTED) | |
3005 | log_error_errno(r, "Incorrect passphrase, try again!"); | |
3006 | else if (r != -ENOKEY) | |
3007 | return log_error_errno(r, "Failed to decrypt image: %m"); | |
3008 | ||
3009 | if (--n < 0) | |
3010 | return log_error_errno(SYNTHETIC_ERRNO(EKEYREJECTED), | |
3011 | "Too many retries."); | |
3012 | ||
3013 | z = strv_free_erase(z); | |
3014 | ||
3015 | static const AskPasswordRequest req = { | |
3016 | .message = "Please enter image passphrase:", | |
3017 | .id = "dissect", | |
3018 | .keyring = "dissect", | |
3019 | .credential = "dissect.passphrase", | |
3020 | }; | |
3021 | ||
3022 | r = ask_password_auto(&req, USEC_INFINITY, /* flags= */ 0, &z); | |
3023 | if (r < 0) | |
3024 | return log_error_errno(r, "Failed to query for passphrase: %m"); | |
3025 | ||
3026 | passphrase = z[0]; | |
3027 | } | |
3028 | } | |
3029 | ||
3030 | static int decrypted_image_relinquish(DecryptedImage *d) { | |
3031 | assert(d); | |
3032 | ||
3033 | /* Turns on automatic removal after the last use ended for all DM devices of this image, and sets a | |
3034 | * boolean so that we don't clean it up ourselves either anymore */ | |
3035 | ||
3036 | #if HAVE_LIBCRYPTSETUP | |
3037 | int r; | |
3038 | ||
3039 | for (size_t i = 0; i < d->n_decrypted; i++) { | |
3040 | DecryptedPartition *p = d->decrypted + i; | |
3041 | ||
3042 | if (p->relinquished) | |
3043 | continue; | |
3044 | ||
3045 | r = sym_crypt_deactivate_by_name(NULL, p->name, CRYPT_DEACTIVATE_DEFERRED); | |
3046 | if (r < 0) | |
3047 | return log_debug_errno(r, "Failed to mark %s for auto-removal: %m", p->name); | |
3048 | ||
3049 | p->relinquished = true; | |
3050 | } | |
3051 | #endif | |
3052 | ||
3053 | return 0; | |
3054 | } | |
3055 | ||
3056 | int dissected_image_relinquish(DissectedImage *m) { | |
3057 | int r; | |
3058 | ||
3059 | assert(m); | |
3060 | ||
3061 | if (m->decrypted_image) { | |
3062 | r = decrypted_image_relinquish(m->decrypted_image); | |
3063 | if (r < 0) | |
3064 | return r; | |
3065 | } | |
3066 | ||
3067 | if (m->loop) | |
3068 | loop_device_relinquish(m->loop); | |
3069 | ||
3070 | return 0; | |
3071 | } | |
3072 | ||
3073 | static char *build_auxiliary_path(const char *image, const char *suffix) { | |
3074 | const char *e; | |
3075 | char *n; | |
3076 | ||
3077 | assert(image); | |
3078 | assert(suffix); | |
3079 | ||
3080 | e = endswith(image, ".raw"); | |
3081 | if (!e) | |
3082 | return strjoin(e, suffix); | |
3083 | ||
3084 | n = new(char, e - image + strlen(suffix) + 1); | |
3085 | if (!n) | |
3086 | return NULL; | |
3087 | ||
3088 | strcpy(mempcpy(n, image, e - image), suffix); | |
3089 | return n; | |
3090 | } | |
3091 | ||
3092 | void verity_settings_done(VeritySettings *v) { | |
3093 | assert(v); | |
3094 | ||
3095 | v->root_hash = mfree(v->root_hash); | |
3096 | v->root_hash_size = 0; | |
3097 | ||
3098 | v->root_hash_sig = mfree(v->root_hash_sig); | |
3099 | v->root_hash_sig_size = 0; | |
3100 | ||
3101 | v->data_path = mfree(v->data_path); | |
3102 | } | |
3103 | ||
3104 | int verity_settings_load( | |
3105 | VeritySettings *verity, | |
3106 | const char *image, | |
3107 | const char *root_hash_path, | |
3108 | const char *root_hash_sig_path) { | |
3109 | ||
3110 | _cleanup_free_ void *root_hash = NULL, *root_hash_sig = NULL; | |
3111 | size_t root_hash_size = 0, root_hash_sig_size = 0; | |
3112 | _cleanup_free_ char *verity_data_path = NULL; | |
3113 | PartitionDesignator designator; | |
3114 | int r; | |
3115 | ||
3116 | assert(verity); | |
3117 | assert(image); | |
3118 | assert(verity->designator < 0 || IN_SET(verity->designator, PARTITION_ROOT, PARTITION_USR)); | |
3119 | ||
3120 | /* If we are asked to load the root hash for a device node, exit early */ | |
3121 | if (is_device_path(image)) | |
3122 | return 0; | |
3123 | ||
3124 | r = secure_getenv_bool("SYSTEMD_DISSECT_VERITY_SIDECAR"); | |
3125 | if (r < 0 && r != -ENXIO) | |
3126 | log_debug_errno(r, "Failed to parse $SYSTEMD_DISSECT_VERITY_SIDECAR, ignoring: %m"); | |
3127 | if (r == 0) | |
3128 | return 0; | |
3129 | ||
3130 | designator = verity->designator; | |
3131 | ||
3132 | /* We only fill in what isn't already filled in */ | |
3133 | ||
3134 | if (!verity->root_hash) { | |
3135 | _cleanup_free_ char *text = NULL; | |
3136 | ||
3137 | if (root_hash_path) { | |
3138 | /* If explicitly specified it takes precedence */ | |
3139 | r = read_one_line_file(root_hash_path, &text); | |
3140 | if (r < 0) | |
3141 | return r; | |
3142 | ||
3143 | if (designator < 0) | |
3144 | designator = PARTITION_ROOT; | |
3145 | } else { | |
3146 | /* Otherwise look for xattr and separate file, and first for the data for root and if | |
3147 | * that doesn't exist for /usr */ | |
3148 | ||
3149 | if (designator < 0 || designator == PARTITION_ROOT) { | |
3150 | r = getxattr_malloc(image, "user.verity.roothash", &text); | |
3151 | if (r < 0) { | |
3152 | _cleanup_free_ char *p = NULL; | |
3153 | ||
3154 | if (r != -ENOENT && !ERRNO_IS_XATTR_ABSENT(r)) | |
3155 | return r; | |
3156 | ||
3157 | p = build_auxiliary_path(image, ".roothash"); | |
3158 | if (!p) | |
3159 | return -ENOMEM; | |
3160 | ||
3161 | r = read_one_line_file(p, &text); | |
3162 | if (r < 0 && r != -ENOENT) | |
3163 | return r; | |
3164 | } | |
3165 | ||
3166 | if (text) | |
3167 | designator = PARTITION_ROOT; | |
3168 | } | |
3169 | ||
3170 | if (!text && (designator < 0 || designator == PARTITION_USR)) { | |
3171 | /* So in the "roothash" xattr/file name above the "root" of course primarily | |
3172 | * refers to the root of the Verity Merkle tree. But coincidentally it also | |
3173 | * is the hash for the *root* file system, i.e. the "root" neatly refers to | |
3174 | * two distinct concepts called "root". Taking benefit of this happy | |
3175 | * coincidence we call the file with the root hash for the /usr/ file system | |
3176 | * `usrhash`, because `usrroothash` or `rootusrhash` would just be too | |
3177 | * confusing. We thus drop the reference to the root of the Merkle tree, and | |
3178 | * just indicate which file system it's about. */ | |
3179 | r = getxattr_malloc(image, "user.verity.usrhash", &text); | |
3180 | if (r < 0) { | |
3181 | _cleanup_free_ char *p = NULL; | |
3182 | ||
3183 | if (r != -ENOENT && !ERRNO_IS_XATTR_ABSENT(r)) | |
3184 | return r; | |
3185 | ||
3186 | p = build_auxiliary_path(image, ".usrhash"); | |
3187 | if (!p) | |
3188 | return -ENOMEM; | |
3189 | ||
3190 | r = read_one_line_file(p, &text); | |
3191 | if (r < 0 && r != -ENOENT) | |
3192 | return r; | |
3193 | } | |
3194 | ||
3195 | if (text) | |
3196 | designator = PARTITION_USR; | |
3197 | } | |
3198 | } | |
3199 | ||
3200 | if (text) { | |
3201 | r = unhexmem(text, &root_hash, &root_hash_size); | |
3202 | if (r < 0) | |
3203 | return r; | |
3204 | if (root_hash_size < sizeof(sd_id128_t)) | |
3205 | return -EINVAL; | |
3206 | } | |
3207 | } | |
3208 | ||
3209 | if ((root_hash || verity->root_hash) && !verity->root_hash_sig) { | |
3210 | if (root_hash_sig_path) { | |
3211 | r = read_full_file(root_hash_sig_path, (char**) &root_hash_sig, &root_hash_sig_size); | |
3212 | if (r < 0 && r != -ENOENT) | |
3213 | return r; | |
3214 | ||
3215 | if (designator < 0) | |
3216 | designator = PARTITION_ROOT; | |
3217 | } else { | |
3218 | if (designator < 0 || designator == PARTITION_ROOT) { | |
3219 | _cleanup_free_ char *p = NULL; | |
3220 | ||
3221 | /* Follow naming convention recommended by the relevant RFC: | |
3222 | * https://tools.ietf.org/html/rfc5751#section-3.2.1 */ | |
3223 | p = build_auxiliary_path(image, ".roothash.p7s"); | |
3224 | if (!p) | |
3225 | return -ENOMEM; | |
3226 | ||
3227 | r = read_full_file(p, (char**) &root_hash_sig, &root_hash_sig_size); | |
3228 | if (r < 0 && r != -ENOENT) | |
3229 | return r; | |
3230 | if (r >= 0) | |
3231 | designator = PARTITION_ROOT; | |
3232 | } | |
3233 | ||
3234 | if (!root_hash_sig && (designator < 0 || designator == PARTITION_USR)) { | |
3235 | _cleanup_free_ char *p = NULL; | |
3236 | ||
3237 | p = build_auxiliary_path(image, ".usrhash.p7s"); | |
3238 | if (!p) | |
3239 | return -ENOMEM; | |
3240 | ||
3241 | r = read_full_file(p, (char**) &root_hash_sig, &root_hash_sig_size); | |
3242 | if (r < 0 && r != -ENOENT) | |
3243 | return r; | |
3244 | if (r >= 0) | |
3245 | designator = PARTITION_USR; | |
3246 | } | |
3247 | } | |
3248 | ||
3249 | if (root_hash_sig && root_hash_sig_size == 0) /* refuse empty size signatures */ | |
3250 | return -EINVAL; | |
3251 | } | |
3252 | ||
3253 | if (!verity->data_path) { | |
3254 | _cleanup_free_ char *p = NULL; | |
3255 | ||
3256 | p = build_auxiliary_path(image, ".verity"); | |
3257 | if (!p) | |
3258 | return -ENOMEM; | |
3259 | ||
3260 | if (access(p, F_OK) < 0) { | |
3261 | if (errno != ENOENT) | |
3262 | return -errno; | |
3263 | } else | |
3264 | verity_data_path = TAKE_PTR(p); | |
3265 | } | |
3266 | ||
3267 | if (root_hash) { | |
3268 | verity->root_hash = TAKE_PTR(root_hash); | |
3269 | verity->root_hash_size = root_hash_size; | |
3270 | } | |
3271 | ||
3272 | if (root_hash_sig) { | |
3273 | verity->root_hash_sig = TAKE_PTR(root_hash_sig); | |
3274 | verity->root_hash_sig_size = root_hash_sig_size; | |
3275 | } | |
3276 | ||
3277 | if (verity_data_path) | |
3278 | verity->data_path = TAKE_PTR(verity_data_path); | |
3279 | ||
3280 | if (verity->designator < 0) | |
3281 | verity->designator = designator; | |
3282 | ||
3283 | return 1; | |
3284 | } | |
3285 | ||
3286 | int dissected_image_load_verity_sig_partition( | |
3287 | DissectedImage *m, | |
3288 | int fd, | |
3289 | VeritySettings *verity) { | |
3290 | ||
3291 | _cleanup_free_ void *root_hash = NULL, *root_hash_sig = NULL; | |
3292 | _cleanup_(json_variant_unrefp) JsonVariant *v = NULL; | |
3293 | size_t root_hash_size, root_hash_sig_size; | |
3294 | _cleanup_free_ char *buf = NULL; | |
3295 | PartitionDesignator d; | |
3296 | DissectedPartition *p; | |
3297 | JsonVariant *rh, *sig; | |
3298 | ssize_t n; | |
3299 | char *e; | |
3300 | int r; | |
3301 | ||
3302 | assert(m); | |
3303 | assert(fd >= 0); | |
3304 | assert(verity); | |
3305 | ||
3306 | if (verity->root_hash && verity->root_hash_sig) /* Already loaded? */ | |
3307 | return 0; | |
3308 | ||
3309 | r = secure_getenv_bool("SYSTEMD_DISSECT_VERITY_EMBEDDED"); | |
3310 | if (r < 0 && r != -ENXIO) | |
3311 | log_debug_errno(r, "Failed to parse $SYSTEMD_DISSECT_VERITY_EMBEDDED, ignoring: %m"); | |
3312 | if (r == 0) | |
3313 | return 0; | |
3314 | ||
3315 | d = partition_verity_sig_of(verity->designator < 0 ? PARTITION_ROOT : verity->designator); | |
3316 | assert(d >= 0); | |
3317 | ||
3318 | p = m->partitions + d; | |
3319 | if (!p->found) | |
3320 | return 0; | |
3321 | if (p->offset == UINT64_MAX || p->size == UINT64_MAX) | |
3322 | return -EINVAL; | |
3323 | ||
3324 | if (p->size > 4*1024*1024) /* Signature data cannot possible be larger than 4M, refuse that */ | |
3325 | return log_debug_errno(SYNTHETIC_ERRNO(EFBIG), "Verity signature partition is larger than 4M, refusing."); | |
3326 | ||
3327 | buf = new(char, p->size+1); | |
3328 | if (!buf) | |
3329 | return -ENOMEM; | |
3330 | ||
3331 | n = pread(fd, buf, p->size, p->offset); | |
3332 | if (n < 0) | |
3333 | return -ENOMEM; | |
3334 | if ((uint64_t) n != p->size) | |
3335 | return -EIO; | |
3336 | ||
3337 | e = memchr(buf, 0, p->size); | |
3338 | if (e) { | |
3339 | /* If we found a NUL byte then the rest of the data must be NUL too */ | |
3340 | if (!memeqzero(e, p->size - (e - buf))) | |
3341 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Signature data contains embedded NUL byte."); | |
3342 | } else | |
3343 | buf[p->size] = 0; | |
3344 | ||
3345 | r = json_parse(buf, 0, &v, NULL, NULL); | |
3346 | if (r < 0) | |
3347 | return log_debug_errno(r, "Failed to parse signature JSON data: %m"); | |
3348 | ||
3349 | rh = json_variant_by_key(v, "rootHash"); | |
3350 | if (!rh) | |
3351 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Signature JSON object lacks 'rootHash' field."); | |
3352 | if (!json_variant_is_string(rh)) | |
3353 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "'rootHash' field of signature JSON object is not a string."); | |
3354 | ||
3355 | r = unhexmem(json_variant_string(rh), &root_hash, &root_hash_size); | |
3356 | if (r < 0) | |
3357 | return log_debug_errno(r, "Failed to parse root hash field: %m"); | |
3358 | ||
3359 | /* Check if specified root hash matches if it is specified */ | |
3360 | if (verity->root_hash && | |
3361 | memcmp_nn(verity->root_hash, verity->root_hash_size, root_hash, root_hash_size) != 0) { | |
3362 | _cleanup_free_ char *a = NULL, *b = NULL; | |
3363 | ||
3364 | a = hexmem(root_hash, root_hash_size); | |
3365 | b = hexmem(verity->root_hash, verity->root_hash_size); | |
3366 | ||
3367 | return log_debug_errno(r, "Root hash in signature JSON data (%s) doesn't match configured hash (%s).", strna(a), strna(b)); | |
3368 | } | |
3369 | ||
3370 | sig = json_variant_by_key(v, "signature"); | |
3371 | if (!sig) | |
3372 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Signature JSON object lacks 'signature' field."); | |
3373 | if (!json_variant_is_string(sig)) | |
3374 | return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "'signature' field of signature JSON object is not a string."); | |
3375 | ||
3376 | r = unbase64mem(json_variant_string(sig), &root_hash_sig, &root_hash_sig_size); | |
3377 | if (r < 0) | |
3378 | return log_debug_errno(r, "Failed to parse signature field: %m"); | |
3379 | ||
3380 | free_and_replace(verity->root_hash, root_hash); | |
3381 | verity->root_hash_size = root_hash_size; | |
3382 | ||
3383 | free_and_replace(verity->root_hash_sig, root_hash_sig); | |
3384 | verity->root_hash_sig_size = root_hash_sig_size; | |
3385 | ||
3386 | return 1; | |
3387 | } | |
3388 | ||
3389 | int dissected_image_acquire_metadata(DissectedImage *m, DissectImageFlags extra_flags) { | |
3390 | ||
3391 | enum { | |
3392 | META_HOSTNAME, | |
3393 | META_MACHINE_ID, | |
3394 | META_MACHINE_INFO, | |
3395 | META_OS_RELEASE, | |
3396 | META_INITRD_RELEASE, | |
3397 | META_SYSEXT_RELEASE, | |
3398 | META_CONFEXT_RELEASE, | |
3399 | META_HAS_INIT_SYSTEM, | |
3400 | _META_MAX, | |
3401 | }; | |
3402 | ||
3403 | static const char *const paths[_META_MAX] = { | |
3404 | [META_HOSTNAME] = "/etc/hostname\0", | |
3405 | [META_MACHINE_ID] = "/etc/machine-id\0", | |
3406 | [META_MACHINE_INFO] = "/etc/machine-info\0", | |
3407 | [META_OS_RELEASE] = "/etc/os-release\0" | |
3408 | "/usr/lib/os-release\0", | |
3409 | [META_INITRD_RELEASE] = "/etc/initrd-release\0" | |
3410 | "/usr/lib/initrd-release\0", | |
3411 | [META_SYSEXT_RELEASE] = "sysext-release\0", /* String used only for logging. */ | |
3412 | [META_CONFEXT_RELEASE] = "confext-release\0", /* ditto */ | |
3413 | [META_HAS_INIT_SYSTEM] = "has-init-system\0", /* ditto */ | |
3414 | }; | |
3415 | ||
3416 | _cleanup_strv_free_ char **machine_info = NULL, **os_release = NULL, **initrd_release = NULL, **sysext_release = NULL, **confext_release = NULL; | |
3417 | _cleanup_free_ char *hostname = NULL, *t = NULL; | |
3418 | _cleanup_close_pair_ int error_pipe[2] = EBADF_PAIR; | |
3419 | _cleanup_(sigkill_waitp) pid_t child = 0; | |
3420 | sd_id128_t machine_id = SD_ID128_NULL; | |
3421 | unsigned n_meta_initialized = 0; | |
3422 | int fds[2 * _META_MAX], r, v; | |
3423 | int has_init_system = -1; | |
3424 | ssize_t n; | |
3425 | ||
3426 | BLOCK_SIGNALS(SIGCHLD); | |
3427 | ||
3428 | assert(m); | |
3429 | ||
3430 | for (; n_meta_initialized < _META_MAX; n_meta_initialized++) { | |
3431 | assert(paths[n_meta_initialized]); | |
3432 | ||
3433 | if (pipe2(fds + 2*n_meta_initialized, O_CLOEXEC) < 0) { | |
3434 | r = -errno; | |
3435 | goto finish; | |
3436 | } | |
3437 | } | |
3438 | ||
3439 | r = get_common_dissect_directory(&t); | |
3440 | if (r < 0) | |
3441 | goto finish; | |
3442 | ||
3443 | if (pipe2(error_pipe, O_CLOEXEC) < 0) { | |
3444 | r = -errno; | |
3445 | goto finish; | |
3446 | } | |
3447 | ||
3448 | r = safe_fork("(sd-dissect)", FORK_RESET_SIGNALS|FORK_DEATHSIG_SIGTERM|FORK_NEW_MOUNTNS|FORK_MOUNTNS_SLAVE, &child); | |
3449 | if (r < 0) | |
3450 | goto finish; | |
3451 | if (r == 0) { | |
3452 | /* Child in a new mount namespace */ | |
3453 | error_pipe[0] = safe_close(error_pipe[0]); | |
3454 | ||
3455 | r = dissected_image_mount( | |
3456 | m, | |
3457 | t, | |
3458 | /* uid_shift= */ UID_INVALID, | |
3459 | /* uid_range= */ UID_INVALID, | |
3460 | /* userns_fd= */ -EBADF, | |
3461 | extra_flags | | |
3462 | DISSECT_IMAGE_READ_ONLY | | |
3463 | DISSECT_IMAGE_MOUNT_ROOT_ONLY | | |
3464 | DISSECT_IMAGE_USR_NO_ROOT); | |
3465 | if (r < 0) { | |
3466 | log_debug_errno(r, "Failed to mount dissected image: %m"); | |
3467 | goto inner_fail; | |
3468 | } | |
3469 | ||
3470 | for (unsigned k = 0; k < _META_MAX; k++) { | |
3471 | _cleanup_close_ int fd = -ENOENT; | |
3472 | ||
3473 | assert(paths[k]); | |
3474 | ||
3475 | fds[2*k] = safe_close(fds[2*k]); | |
3476 | ||
3477 | switch (k) { | |
3478 | ||
3479 | case META_SYSEXT_RELEASE: | |
3480 | if (!m->image_name) | |
3481 | goto next; | |
3482 | ||
3483 | /* As per the os-release spec, if the image is an extension it will have a | |
3484 | * file named after the image name in extension-release.d/ - we use the image | |
3485 | * name and try to resolve it with the extension-release helpers, as | |
3486 | * sometimes the image names are mangled on deployment and do not match | |
3487 | * anymore. Unlike other paths this is not fixed, and the image name can be | |
3488 | * mangled on deployment, so by calling into the helper we allow a fallback | |
3489 | * that matches on the first extension-release file found in the directory, | |
3490 | * if one named after the image cannot be found first. */ | |
3491 | r = open_extension_release( | |
3492 | t, | |
3493 | IMAGE_SYSEXT, | |
3494 | m->image_name, | |
3495 | /* relax_extension_release_check= */ false, | |
3496 | /* ret_path= */ NULL, | |
3497 | &fd); | |
3498 | if (r < 0) | |
3499 | fd = r; | |
3500 | break; | |
3501 | ||
3502 | case META_CONFEXT_RELEASE: | |
3503 | if (!m->image_name) | |
3504 | goto next; | |
3505 | ||
3506 | /* As above */ | |
3507 | r = open_extension_release( | |
3508 | t, | |
3509 | IMAGE_CONFEXT, | |
3510 | m->image_name, | |
3511 | /* relax_extension_release_check= */ false, | |
3512 | /* ret_path= */ NULL, | |
3513 | &fd); | |
3514 | if (r < 0) | |
3515 | fd = r; | |
3516 | ||
3517 | break; | |
3518 | ||
3519 | case META_HAS_INIT_SYSTEM: { | |
3520 | bool found = false; | |
3521 | ||
3522 | FOREACH_STRING(init, | |
3523 | "/usr/lib/systemd/systemd", /* systemd on /usr/ merged system */ | |
3524 | "/lib/systemd/systemd", /* systemd on /usr/ non-merged systems */ | |
3525 | "/sbin/init") { /* traditional path the Linux kernel invokes */ | |
3526 | ||
3527 | r = chase(init, t, CHASE_PREFIX_ROOT, NULL, NULL); | |
3528 | if (r < 0) { | |
3529 | if (r != -ENOENT) | |
3530 | log_debug_errno(r, "Failed to resolve %s, ignoring: %m", init); | |
3531 | } else { | |
3532 | found = true; | |
3533 | break; | |
3534 | } | |
3535 | } | |
3536 | ||
3537 | r = loop_write(fds[2*k+1], &found, sizeof(found)); | |
3538 | if (r < 0) | |
3539 | goto inner_fail; | |
3540 | ||
3541 | goto next; | |
3542 | } | |
3543 | ||
3544 | default: | |
3545 | NULSTR_FOREACH(p, paths[k]) { | |
3546 | fd = chase_and_open(p, t, CHASE_PREFIX_ROOT, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL); | |
3547 | if (fd >= 0) | |
3548 | break; | |
3549 | } | |
3550 | } | |
3551 | ||
3552 | if (fd < 0) { | |
3553 | log_debug_errno(fd, "Failed to read %s file of image, ignoring: %m", paths[k]); | |
3554 | goto next; | |
3555 | } | |
3556 | ||
3557 | r = copy_bytes(fd, fds[2*k+1], UINT64_MAX, 0); | |
3558 | if (r < 0) | |
3559 | goto inner_fail; | |
3560 | ||
3561 | next: | |
3562 | fds[2*k+1] = safe_close(fds[2*k+1]); | |
3563 | } | |
3564 | ||
3565 | _exit(EXIT_SUCCESS); | |
3566 | ||
3567 | inner_fail: | |
3568 | /* Let parent know the error */ | |
3569 | (void) write(error_pipe[1], &r, sizeof(r)); | |
3570 | _exit(EXIT_FAILURE); | |
3571 | } | |
3572 | ||
3573 | error_pipe[1] = safe_close(error_pipe[1]); | |
3574 | ||
3575 | for (unsigned k = 0; k < _META_MAX; k++) { | |
3576 | _cleanup_fclose_ FILE *f = NULL; | |
3577 | ||
3578 | assert(paths[k]); | |
3579 | ||
3580 | fds[2*k+1] = safe_close(fds[2*k+1]); | |
3581 | ||
3582 | f = take_fdopen(&fds[2*k], "r"); | |
3583 | if (!f) { | |
3584 | r = -errno; | |
3585 | goto finish; | |
3586 | } | |
3587 | ||
3588 | switch (k) { | |
3589 | ||
3590 | case META_HOSTNAME: | |
3591 | r = read_etc_hostname_stream(f, &hostname); | |
3592 | if (r < 0) | |
3593 | log_debug_errno(r, "Failed to read /etc/hostname of image: %m"); | |
3594 | ||
3595 | break; | |
3596 | ||
3597 | case META_MACHINE_ID: { | |
3598 | _cleanup_free_ char *line = NULL; | |
3599 | ||
3600 | r = read_line(f, LONG_LINE_MAX, &line); | |
3601 | if (r < 0) | |
3602 | log_debug_errno(r, "Failed to read /etc/machine-id of image: %m"); | |
3603 | else if (r == 33) { | |
3604 | r = sd_id128_from_string(line, &machine_id); | |
3605 | if (r < 0) | |
3606 | log_debug_errno(r, "Image contains invalid /etc/machine-id: %s", line); | |
3607 | } else if (r == 0) | |
3608 | log_debug("/etc/machine-id file of image is empty."); | |
3609 | else if (streq(line, "uninitialized")) | |
3610 | log_debug("/etc/machine-id file of image is uninitialized (likely aborted first boot)."); | |
3611 | else | |
3612 | log_debug("/etc/machine-id file of image has unexpected length %i.", r); | |
3613 | ||
3614 | break; | |
3615 | } | |
3616 | ||
3617 | case META_MACHINE_INFO: | |
3618 | r = load_env_file_pairs(f, "machine-info", &machine_info); | |
3619 | if (r < 0) | |
3620 | log_debug_errno(r, "Failed to read /etc/machine-info of image: %m"); | |
3621 | ||
3622 | break; | |
3623 | ||
3624 | case META_OS_RELEASE: | |
3625 | r = load_env_file_pairs(f, "os-release", &os_release); | |
3626 | if (r < 0) | |
3627 | log_debug_errno(r, "Failed to read OS release file of image: %m"); | |
3628 | ||
3629 | break; | |
3630 | ||
3631 | case META_INITRD_RELEASE: | |
3632 | r = load_env_file_pairs(f, "initrd-release", &initrd_release); | |
3633 | if (r < 0) | |
3634 | log_debug_errno(r, "Failed to read initrd release file of image: %m"); | |
3635 | ||
3636 | break; | |
3637 | ||
3638 | case META_SYSEXT_RELEASE: | |
3639 | r = load_env_file_pairs(f, "sysext-release", &sysext_release); | |
3640 | if (r < 0) | |
3641 | log_debug_errno(r, "Failed to read sysext release file of image: %m"); | |
3642 | ||
3643 | break; | |
3644 | ||
3645 | case META_CONFEXT_RELEASE: | |
3646 | r = load_env_file_pairs(f, "confext-release", &confext_release); | |
3647 | if (r < 0) | |
3648 | log_debug_errno(r, "Failed to read confext release file of image: %m"); | |
3649 | ||
3650 | break; | |
3651 | ||
3652 | case META_HAS_INIT_SYSTEM: { | |
3653 | bool b = false; | |
3654 | size_t nr; | |
3655 | ||
3656 | errno = 0; | |
3657 | nr = fread(&b, 1, sizeof(b), f); | |
3658 | if (nr != sizeof(b)) | |
3659 | log_debug_errno(errno_or_else(EIO), "Failed to read has-init-system boolean: %m"); | |
3660 | else | |
3661 | has_init_system = b; | |
3662 | ||
3663 | break; | |
3664 | }} | |
3665 | } | |
3666 | ||
3667 | r = wait_for_terminate_and_check("(sd-dissect)", child, 0); | |
3668 | child = 0; | |
3669 | if (r < 0) | |
3670 | goto finish; | |
3671 | ||
3672 | n = read(error_pipe[0], &v, sizeof(v)); | |
3673 | if (n < 0) { | |
3674 | r = -errno; | |
3675 | goto finish; | |
3676 | } | |
3677 | if (n == sizeof(v)) { | |
3678 | r = v; /* propagate error sent to us from child */ | |
3679 | goto finish; | |
3680 | } | |
3681 | if (n != 0) { | |
3682 | r = -EIO; | |
3683 | goto finish; | |
3684 | } | |
3685 | if (r != EXIT_SUCCESS) { | |
3686 | r = -EPROTO; | |
3687 | goto finish; | |
3688 | } | |
3689 | ||
3690 | free_and_replace(m->hostname, hostname); | |
3691 | m->machine_id = machine_id; | |
3692 | strv_free_and_replace(m->machine_info, machine_info); | |
3693 | strv_free_and_replace(m->os_release, os_release); | |
3694 | strv_free_and_replace(m->initrd_release, initrd_release); | |
3695 | strv_free_and_replace(m->sysext_release, sysext_release); | |
3696 | strv_free_and_replace(m->confext_release, confext_release); | |
3697 | m->has_init_system = has_init_system; | |
3698 | ||
3699 | finish: | |
3700 | for (unsigned k = 0; k < n_meta_initialized; k++) | |
3701 | safe_close_pair(fds + 2*k); | |
3702 | ||
3703 | return r; | |
3704 | } | |
3705 | ||
3706 | Architecture dissected_image_architecture(DissectedImage *img) { | |
3707 | assert(img); | |
3708 | ||
3709 | if (img->partitions[PARTITION_ROOT].found && | |
3710 | img->partitions[PARTITION_ROOT].architecture >= 0) | |
3711 | return img->partitions[PARTITION_ROOT].architecture; | |
3712 | ||
3713 | if (img->partitions[PARTITION_USR].found && | |
3714 | img->partitions[PARTITION_USR].architecture >= 0) | |
3715 | return img->partitions[PARTITION_USR].architecture; | |
3716 | ||
3717 | return _ARCHITECTURE_INVALID; | |
3718 | } | |
3719 | ||
3720 | int dissect_loop_device( | |
3721 | LoopDevice *loop, | |
3722 | const VeritySettings *verity, | |
3723 | const MountOptions *mount_options, | |
3724 | const ImagePolicy *image_policy, | |
3725 | DissectImageFlags flags, | |
3726 | DissectedImage **ret) { | |
3727 | ||
3728 | #if HAVE_BLKID | |
3729 | _cleanup_(dissected_image_unrefp) DissectedImage *m = NULL; | |
3730 | int r; | |
3731 | ||
3732 | assert(loop); | |
3733 | ||
3734 | r = dissected_image_new(loop->backing_file ?: loop->node, &m); | |
3735 | if (r < 0) | |
3736 | return r; | |
3737 | ||
3738 | m->loop = loop_device_ref(loop); | |
3739 | m->image_size = m->loop->device_size; | |
3740 | m->sector_size = m->loop->sector_size; | |
3741 | ||
3742 | r = dissect_image(m, loop->fd, loop->node, verity, mount_options, image_policy, flags); | |
3743 | if (r < 0) | |
3744 | return r; | |
3745 | ||
3746 | if (ret) | |
3747 | *ret = TAKE_PTR(m); | |
3748 | ||
3749 | return 0; | |
3750 | #else | |
3751 | return -EOPNOTSUPP; | |
3752 | #endif | |
3753 | } | |
3754 | ||
3755 | int dissect_loop_device_and_warn( | |
3756 | LoopDevice *loop, | |
3757 | const VeritySettings *verity, | |
3758 | const MountOptions *mount_options, | |
3759 | const ImagePolicy *image_policy, | |
3760 | DissectImageFlags flags, | |
3761 | DissectedImage **ret) { | |
3762 | ||
3763 | assert(loop); | |
3764 | ||
3765 | return dissect_log_error( | |
3766 | LOG_ERR, | |
3767 | dissect_loop_device(loop, verity, mount_options, image_policy, flags, ret), | |
3768 | loop->backing_file ?: loop->node, | |
3769 | verity); | |
3770 | ||
3771 | } | |
3772 | ||
3773 | bool dissected_image_verity_candidate(const DissectedImage *image, PartitionDesignator partition_designator) { | |
3774 | assert(image); | |
3775 | ||
3776 | /* Checks if this partition could theoretically do Verity. For non-partitioned images this only works | |
3777 | * if there's an external verity file supplied, for which we can consult .has_verity. For partitioned | |
3778 | * images we only check the partition type. | |
3779 | * | |
3780 | * This call is used to decide whether to suppress or show a verity column in tabular output of the | |
3781 | * image. */ | |
3782 | ||
3783 | if (image->single_file_system) | |
3784 | return partition_designator == PARTITION_ROOT && image->has_verity; | |
3785 | ||
3786 | return partition_verity_of(partition_designator) >= 0; | |
3787 | } | |
3788 | ||
3789 | bool dissected_image_verity_ready(const DissectedImage *image, PartitionDesignator partition_designator) { | |
3790 | PartitionDesignator k; | |
3791 | ||
3792 | assert(image); | |
3793 | ||
3794 | /* Checks if this partition has verity data available that we can activate. For non-partitioned this | |
3795 | * works for the root partition, for others only if the associated verity partition was found. */ | |
3796 | ||
3797 | if (!image->verity_ready) | |
3798 | return false; | |
3799 | ||
3800 | if (image->single_file_system) | |
3801 | return partition_designator == PARTITION_ROOT; | |
3802 | ||
3803 | k = partition_verity_of(partition_designator); | |
3804 | return k >= 0 && image->partitions[k].found; | |
3805 | } | |
3806 | ||
3807 | bool dissected_image_verity_sig_ready(const DissectedImage *image, PartitionDesignator partition_designator) { | |
3808 | PartitionDesignator k; | |
3809 | ||
3810 | assert(image); | |
3811 | ||
3812 | /* Checks if this partition has verity signature data available that we can use. */ | |
3813 | ||
3814 | if (!image->verity_sig_ready) | |
3815 | return false; | |
3816 | ||
3817 | if (image->single_file_system) | |
3818 | return partition_designator == PARTITION_ROOT; | |
3819 | ||
3820 | k = partition_verity_sig_of(partition_designator); | |
3821 | return k >= 0 && image->partitions[k].found; | |
3822 | } | |
3823 | ||
3824 | MountOptions* mount_options_free_all(MountOptions *options) { | |
3825 | MountOptions *m; | |
3826 | ||
3827 | while ((m = LIST_POP(mount_options, options))) { | |
3828 | free(m->options); | |
3829 | free(m); | |
3830 | } | |
3831 | ||
3832 | return NULL; | |
3833 | } | |
3834 | ||
3835 | const char* mount_options_from_designator(const MountOptions *options, PartitionDesignator designator) { | |
3836 | LIST_FOREACH(mount_options, m, options) | |
3837 | if (designator == m->partition_designator && !isempty(m->options)) | |
3838 | return m->options; | |
3839 | ||
3840 | return NULL; | |
3841 | } | |
3842 | ||
3843 | int mount_image_privately_interactively( | |
3844 | const char *image, | |
3845 | const ImagePolicy *image_policy, | |
3846 | DissectImageFlags flags, | |
3847 | char **ret_directory, | |
3848 | int *ret_dir_fd, | |
3849 | LoopDevice **ret_loop_device) { | |
3850 | ||
3851 | _cleanup_(verity_settings_done) VeritySettings verity = VERITY_SETTINGS_DEFAULT; | |
3852 | _cleanup_(loop_device_unrefp) LoopDevice *d = NULL; | |
3853 | _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL; | |
3854 | _cleanup_free_ char *dir = NULL; | |
3855 | int r; | |
3856 | ||
3857 | /* Mounts an OS image at a temporary place, inside a newly created mount namespace of our own. This | |
3858 | * is used by tools such as systemd-tmpfiles or systemd-firstboot to operate on some disk image | |
3859 | * easily. */ | |
3860 | ||
3861 | assert(image); | |
3862 | assert(ret_loop_device); | |
3863 | ||
3864 | /* We intend to mount this right-away, hence add the partitions if needed and pin them. */ | |
3865 | flags |= DISSECT_IMAGE_ADD_PARTITION_DEVICES | | |
3866 | DISSECT_IMAGE_PIN_PARTITION_DEVICES; | |
3867 | ||
3868 | r = verity_settings_load(&verity, image, NULL, NULL); | |
3869 | if (r < 0) | |
3870 | return log_error_errno(r, "Failed to load root hash data: %m"); | |
3871 | ||
3872 | r = loop_device_make_by_path( | |
3873 | image, | |
3874 | FLAGS_SET(flags, DISSECT_IMAGE_DEVICE_READ_ONLY) ? O_RDONLY : O_RDWR, | |
3875 | /* sector_size= */ UINT32_MAX, | |
3876 | FLAGS_SET(flags, DISSECT_IMAGE_NO_PARTITION_TABLE) ? 0 : LO_FLAGS_PARTSCAN, | |
3877 | LOCK_SH, | |
3878 | &d); | |
3879 | if (r < 0) | |
3880 | return log_error_errno(r, "Failed to set up loopback device for %s: %m", image); | |
3881 | ||
3882 | r = dissect_loop_device_and_warn( | |
3883 | d, | |
3884 | &verity, | |
3885 | /* mount_options= */ NULL, | |
3886 | image_policy, | |
3887 | flags, | |
3888 | &dissected_image); | |
3889 | if (r < 0) | |
3890 | return r; | |
3891 | ||
3892 | r = dissected_image_load_verity_sig_partition(dissected_image, d->fd, &verity); | |
3893 | if (r < 0) | |
3894 | return r; | |
3895 | ||
3896 | r = dissected_image_decrypt_interactively(dissected_image, NULL, &verity, flags); | |
3897 | if (r < 0) | |
3898 | return r; | |
3899 | ||
3900 | r = detach_mount_namespace(); | |
3901 | if (r < 0) | |
3902 | return log_error_errno(r, "Failed to detach mount namespace: %m"); | |
3903 | ||
3904 | r = mkdir_p("/run/systemd/mount-rootfs", 0555); | |
3905 | if (r < 0) | |
3906 | return log_error_errno(r, "Failed to create mount point: %m"); | |
3907 | ||
3908 | r = dissected_image_mount_and_warn( | |
3909 | dissected_image, | |
3910 | "/run/systemd/mount-rootfs", | |
3911 | /* uid_shift= */ UID_INVALID, | |
3912 | /* uid_range= */ UID_INVALID, | |
3913 | /* userns_fd= */ -EBADF, | |
3914 | flags); | |
3915 | if (r < 0) | |
3916 | return r; | |
3917 | ||
3918 | r = loop_device_flock(d, LOCK_UN); | |
3919 | if (r < 0) | |
3920 | return r; | |
3921 | ||
3922 | r = dissected_image_relinquish(dissected_image); | |
3923 | if (r < 0) | |
3924 | return log_error_errno(r, "Failed to relinquish DM and loopback block devices: %m"); | |
3925 | ||
3926 | if (ret_directory) { | |
3927 | dir = strdup("/run/systemd/mount-rootfs"); | |
3928 | if (!dir) | |
3929 | return log_oom(); | |
3930 | } | |
3931 | ||
3932 | if (ret_dir_fd) { | |
3933 | _cleanup_close_ int dir_fd = -EBADF; | |
3934 | ||
3935 | dir_fd = open("/run/systemd/mount-rootfs", O_CLOEXEC|O_DIRECTORY); | |
3936 | if (dir_fd < 0) | |
3937 | return log_error_errno(errno, "Failed to open mount point directory: %m"); | |
3938 | ||
3939 | *ret_dir_fd = TAKE_FD(dir_fd); | |
3940 | } | |
3941 | ||
3942 | if (ret_directory) | |
3943 | *ret_directory = TAKE_PTR(dir); | |
3944 | ||
3945 | *ret_loop_device = TAKE_PTR(d); | |
3946 | return 0; | |
3947 | } | |
3948 | ||
3949 | static bool mount_options_relax_extension_release_checks(const MountOptions *options) { | |
3950 | if (!options) | |
3951 | return false; | |
3952 | ||
3953 | return string_contains_word(mount_options_from_designator(options, PARTITION_ROOT), ",", "x-systemd.relax-extension-release-check") || | |
3954 | string_contains_word(mount_options_from_designator(options, PARTITION_USR), ",", "x-systemd.relax-extension-release-check") || | |
3955 | string_contains_word(options->options, ",", "x-systemd.relax-extension-release-check"); | |
3956 | } | |
3957 | ||
3958 | int verity_dissect_and_mount( | |
3959 | int src_fd, | |
3960 | const char *src, | |
3961 | const char *dest, | |
3962 | const MountOptions *options, | |
3963 | const ImagePolicy *image_policy, | |
3964 | const char *required_host_os_release_id, | |
3965 | const char *required_host_os_release_version_id, | |
3966 | const char *required_host_os_release_sysext_level, | |
3967 | const char *required_host_os_release_confext_level, | |
3968 | const char *required_sysext_scope, | |
3969 | DissectedImage **ret_image) { | |
3970 | ||
3971 | _cleanup_(loop_device_unrefp) LoopDevice *loop_device = NULL; | |
3972 | _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL; | |
3973 | _cleanup_(verity_settings_done) VeritySettings verity = VERITY_SETTINGS_DEFAULT; | |
3974 | DissectImageFlags dissect_image_flags; | |
3975 | bool relax_extension_release_check; | |
3976 | int r; | |
3977 | ||
3978 | assert(src); | |
3979 | /* Verifying release metadata requires mounted image for now, so ensure the check is skipped when | |
3980 | * opening an image without mounting it immediately (i.e.: 'dest' is NULL). */ | |
3981 | assert(!required_host_os_release_id || dest); | |
3982 | ||
3983 | relax_extension_release_check = mount_options_relax_extension_release_checks(options); | |
3984 | ||
3985 | /* We might get an FD for the image, but we use the original path to look for the dm-verity files */ | |
3986 | r = verity_settings_load(&verity, src, NULL, NULL); | |
3987 | if (r < 0) | |
3988 | return log_debug_errno(r, "Failed to load root hash: %m"); | |
3989 | ||
3990 | dissect_image_flags = | |
3991 | (verity.data_path ? DISSECT_IMAGE_NO_PARTITION_TABLE : 0) | | |
3992 | (relax_extension_release_check ? DISSECT_IMAGE_RELAX_EXTENSION_CHECK : 0) | | |
3993 | DISSECT_IMAGE_ADD_PARTITION_DEVICES | | |
3994 | DISSECT_IMAGE_PIN_PARTITION_DEVICES | | |
3995 | DISSECT_IMAGE_ALLOW_USERSPACE_VERITY; | |
3996 | ||
3997 | /* Note that we don't use loop_device_make here, as the FD is most likely O_PATH which would not be | |
3998 | * accepted by LOOP_CONFIGURE, so just let loop_device_make_by_path reopen it as a regular FD. */ | |
3999 | r = loop_device_make_by_path( | |
4000 | src_fd >= 0 ? FORMAT_PROC_FD_PATH(src_fd) : src, | |
4001 | /* open_flags= */ -1, | |
4002 | /* sector_size= */ UINT32_MAX, | |
4003 | verity.data_path ? 0 : LO_FLAGS_PARTSCAN, | |
4004 | LOCK_SH, | |
4005 | &loop_device); | |
4006 | if (r < 0) | |
4007 | return log_debug_errno(r, "Failed to create loop device for image: %m"); | |
4008 | ||
4009 | r = dissect_loop_device( | |
4010 | loop_device, | |
4011 | &verity, | |
4012 | options, | |
4013 | image_policy, | |
4014 | dissect_image_flags, | |
4015 | &dissected_image); | |
4016 | /* No partition table? Might be a single-filesystem image, try again */ | |
4017 | if (!verity.data_path && r == -ENOPKG) | |
4018 | r = dissect_loop_device( | |
4019 | loop_device, | |
4020 | &verity, | |
4021 | options, | |
4022 | image_policy, | |
4023 | dissect_image_flags | DISSECT_IMAGE_NO_PARTITION_TABLE, | |
4024 | &dissected_image); | |
4025 | if (r < 0) | |
4026 | return log_debug_errno(r, "Failed to dissect image: %m"); | |
4027 | ||
4028 | r = dissected_image_load_verity_sig_partition(dissected_image, loop_device->fd, &verity); | |
4029 | if (r < 0) | |
4030 | return r; | |
4031 | ||
4032 | r = dissected_image_decrypt( | |
4033 | dissected_image, | |
4034 | NULL, | |
4035 | &verity, | |
4036 | dissect_image_flags); | |
4037 | if (r < 0) | |
4038 | return log_debug_errno(r, "Failed to decrypt dissected image: %m"); | |
4039 | ||
4040 | if (dest) { | |
4041 | r = mkdir_p_label(dest, 0755); | |
4042 | if (r < 0) | |
4043 | return log_debug_errno(r, "Failed to create destination directory %s: %m", dest); | |
4044 | r = umount_recursive(dest, 0); | |
4045 | if (r < 0) | |
4046 | return log_debug_errno(r, "Failed to umount under destination directory %s: %m", dest); | |
4047 | } | |
4048 | ||
4049 | r = dissected_image_mount( | |
4050 | dissected_image, | |
4051 | dest, | |
4052 | /* uid_shift= */ UID_INVALID, | |
4053 | /* uid_range= */ UID_INVALID, | |
4054 | /* userns_fd= */ -EBADF, | |
4055 | dissect_image_flags); | |
4056 | if (r < 0) | |
4057 | return log_debug_errno(r, "Failed to mount image: %m"); | |
4058 | ||
4059 | r = loop_device_flock(loop_device, LOCK_UN); | |
4060 | if (r < 0) | |
4061 | return log_debug_errno(r, "Failed to unlock loopback device: %m"); | |
4062 | ||
4063 | /* If we got os-release values from the caller, then we need to match them with the image's | |
4064 | * extension-release.d/ content. Return -EINVAL if there's any mismatch. | |
4065 | * First, check the distro ID. If that matches, then check the new SYSEXT_LEVEL value if | |
4066 | * available, or else fallback to VERSION_ID. If neither is present (eg: rolling release), | |
4067 | * then a simple match on the ID will be performed. */ | |
4068 | if (required_host_os_release_id) { | |
4069 | _cleanup_strv_free_ char **extension_release = NULL; | |
4070 | ImageClass class = IMAGE_SYSEXT; | |
4071 | ||
4072 | assert(!isempty(required_host_os_release_id)); | |
4073 | ||
4074 | r = load_extension_release_pairs(dest, IMAGE_SYSEXT, dissected_image->image_name, relax_extension_release_check, &extension_release); | |
4075 | if (r == -ENOENT) { | |
4076 | r = load_extension_release_pairs(dest, IMAGE_CONFEXT, dissected_image->image_name, relax_extension_release_check, &extension_release); | |
4077 | if (r >= 0) | |
4078 | class = IMAGE_CONFEXT; | |
4079 | } | |
4080 | if (r < 0) | |
4081 | return log_debug_errno(r, "Failed to parse image %s extension-release metadata: %m", dissected_image->image_name); | |
4082 | ||
4083 | r = extension_release_validate( | |
4084 | dissected_image->image_name, | |
4085 | required_host_os_release_id, | |
4086 | required_host_os_release_version_id, | |
4087 | class == IMAGE_SYSEXT ? required_host_os_release_sysext_level : required_host_os_release_confext_level, | |
4088 | required_sysext_scope, | |
4089 | extension_release, | |
4090 | class); | |
4091 | if (r == 0) | |
4092 | return log_debug_errno(SYNTHETIC_ERRNO(ESTALE), "Image %s extension-release metadata does not match the root's", dissected_image->image_name); | |
4093 | if (r < 0) | |
4094 | return log_debug_errno(r, "Failed to compare image %s extension-release metadata with the root's os-release: %m", dissected_image->image_name); | |
4095 | } | |
4096 | ||
4097 | r = dissected_image_relinquish(dissected_image); | |
4098 | if (r < 0) | |
4099 | return log_debug_errno(r, "Failed to relinquish dissected image: %m"); | |
4100 | ||
4101 | if (ret_image) | |
4102 | *ret_image = TAKE_PTR(dissected_image); | |
4103 | ||
4104 | return 0; | |
4105 | } | |
4106 | ||
4107 | int get_common_dissect_directory(char **ret) { | |
4108 | _cleanup_free_ char *t = NULL; | |
4109 | int r; | |
4110 | ||
4111 | /* A common location we mount dissected images to. The assumption is that everyone who uses this | |
4112 | * function runs in their own private mount namespace (with mount propagation off on /run/systemd/, | |
4113 | * and thus can mount something here without affecting anyone else). */ | |
4114 | ||
4115 | t = strdup("/run/systemd/dissect-root"); | |
4116 | if (!t) | |
4117 | return log_oom_debug(); | |
4118 | ||
4119 | r = mkdir_parents(t, 0755); | |
4120 | if (r < 0) | |
4121 | return log_debug_errno(r, "Failed to create parent dirs of mount point '%s': %m", t); | |
4122 | ||
4123 | r = RET_NERRNO(mkdir(t, 0000)); /* It's supposed to be overmounted, hence let's make this inaccessible */ | |
4124 | if (r < 0 && r != -EEXIST) | |
4125 | return log_debug_errno(r, "Failed to create mount point '%s': %m", t); | |
4126 | ||
4127 | if (ret) | |
4128 | *ret = TAKE_PTR(t); | |
4129 | ||
4130 | return 0; | |
4131 | } |