1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Boot config tool for initrd image |
4 | */ |
5 | #include <stdio.h> |
6 | #include <stdlib.h> |
7 | #include <sys/types.h> |
8 | #include <sys/stat.h> |
9 | #include <fcntl.h> |
10 | #include <unistd.h> |
11 | #include <string.h> |
12 | #include <errno.h> |
13 | #include <endian.h> |
14 | |
15 | #include <linux/bootconfig.h> |
16 | |
17 | #define pr_err(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__) |
18 | |
19 | static int xbc_show_value(struct xbc_node *node, bool semicolon) |
20 | { |
21 | const char *val, *eol; |
22 | char q; |
23 | int i = 0; |
24 | |
25 | eol = semicolon ? ";\n" : "\n" ; |
26 | xbc_array_for_each_value(node, val) { |
27 | if (strchr(val, '"')) |
28 | q = '\''; |
29 | else |
30 | q = '"'; |
31 | printf("%c%s%c%s" , q, val, q, xbc_node_is_array(node) ? ", " : eol); |
32 | i++; |
33 | } |
34 | return i; |
35 | } |
36 | |
37 | static void xbc_show_compact_tree(void) |
38 | { |
39 | struct xbc_node *node, *cnode = NULL, *vnode; |
40 | int depth = 0, i; |
41 | |
42 | node = xbc_root_node(); |
43 | while (node && xbc_node_is_key(node)) { |
44 | for (i = 0; i < depth; i++) |
45 | printf("\t" ); |
46 | if (!cnode) |
47 | cnode = xbc_node_get_child(node); |
48 | while (cnode && xbc_node_is_key(node: cnode) && !cnode->next) { |
49 | vnode = xbc_node_get_child(node: cnode); |
50 | /* |
51 | * If @cnode has value and subkeys, this |
52 | * should show it as below. |
53 | * |
54 | * key(@node) { |
55 | * key(@cnode) = value; |
56 | * key(@cnode) { |
57 | * subkeys; |
58 | * } |
59 | * } |
60 | */ |
61 | if (vnode && xbc_node_is_value(node: vnode) && vnode->next) |
62 | break; |
63 | printf("%s." , xbc_node_get_data(node)); |
64 | node = cnode; |
65 | cnode = vnode; |
66 | } |
67 | if (cnode && xbc_node_is_key(node: cnode)) { |
68 | printf("%s {\n" , xbc_node_get_data(node)); |
69 | depth++; |
70 | node = cnode; |
71 | cnode = NULL; |
72 | continue; |
73 | } else if (cnode && xbc_node_is_value(node: cnode)) { |
74 | printf("%s = " , xbc_node_get_data(node)); |
75 | xbc_show_value(node: cnode, semicolon: true); |
76 | /* |
77 | * If @node has value and subkeys, continue |
78 | * looping on subkeys with same node. |
79 | */ |
80 | if (cnode->next) { |
81 | cnode = xbc_node_get_next(node: cnode); |
82 | continue; |
83 | } |
84 | } else { |
85 | printf("%s;\n" , xbc_node_get_data(node)); |
86 | } |
87 | cnode = NULL; |
88 | |
89 | if (node->next) { |
90 | node = xbc_node_get_next(node); |
91 | continue; |
92 | } |
93 | while (!node->next) { |
94 | node = xbc_node_get_parent(node); |
95 | if (!node) |
96 | return; |
97 | if (!xbc_node_get_child(node)->next) |
98 | continue; |
99 | if (depth) { |
100 | depth--; |
101 | for (i = 0; i < depth; i++) |
102 | printf("\t" ); |
103 | printf("}\n" ); |
104 | } |
105 | } |
106 | node = xbc_node_get_next(node); |
107 | } |
108 | } |
109 | |
110 | static void xbc_show_list(void) |
111 | { |
112 | char key[XBC_KEYLEN_MAX]; |
113 | struct xbc_node *leaf; |
114 | const char *val; |
115 | int ret; |
116 | |
117 | xbc_for_each_key_value(leaf, val) { |
118 | ret = xbc_node_compose_key(node: leaf, buf: key, XBC_KEYLEN_MAX); |
119 | if (ret < 0) { |
120 | fprintf(stderr, "Failed to compose key %d\n" , ret); |
121 | break; |
122 | } |
123 | printf("%s = " , key); |
124 | if (!val || val[0] == '\0') { |
125 | printf("\"\"\n" ); |
126 | continue; |
127 | } |
128 | xbc_show_value(node: xbc_node_get_child(node: leaf), semicolon: false); |
129 | } |
130 | } |
131 | |
132 | #define PAGE_SIZE 4096 |
133 | |
134 | static int load_xbc_fd(int fd, char **buf, int size) |
135 | { |
136 | int ret; |
137 | |
138 | *buf = malloc(size + 1); |
139 | if (!*buf) |
140 | return -ENOMEM; |
141 | |
142 | ret = read(fd, *buf, size); |
143 | if (ret < 0) |
144 | return -errno; |
145 | (*buf)[size] = '\0'; |
146 | |
147 | return ret; |
148 | } |
149 | |
150 | /* Return the read size or -errno */ |
151 | static int load_xbc_file(const char *path, char **buf) |
152 | { |
153 | struct stat stat; |
154 | int fd, ret; |
155 | |
156 | fd = open(path, O_RDONLY); |
157 | if (fd < 0) |
158 | return -errno; |
159 | ret = fstat(fd, &stat); |
160 | if (ret < 0) |
161 | return -errno; |
162 | |
163 | ret = load_xbc_fd(fd, buf, size: stat.st_size); |
164 | |
165 | close(fd); |
166 | |
167 | return ret; |
168 | } |
169 | |
170 | static int pr_errno(const char *msg, int err) |
171 | { |
172 | pr_err("%s: %d\n" , msg, err); |
173 | return err; |
174 | } |
175 | |
176 | static int load_xbc_from_initrd(int fd, char **buf) |
177 | { |
178 | struct stat stat; |
179 | int ret; |
180 | uint32_t size = 0, csum = 0, rcsum; |
181 | char magic[BOOTCONFIG_MAGIC_LEN]; |
182 | const char *msg; |
183 | |
184 | ret = fstat(fd, &stat); |
185 | if (ret < 0) |
186 | return -errno; |
187 | |
188 | if (stat.st_size < 8 + BOOTCONFIG_MAGIC_LEN) |
189 | return 0; |
190 | |
191 | if (lseek(fd, -BOOTCONFIG_MAGIC_LEN, SEEK_END) < 0) |
192 | return pr_errno(msg: "Failed to lseek for magic" , err: -errno); |
193 | |
194 | if (read(fd, magic, BOOTCONFIG_MAGIC_LEN) < 0) |
195 | return pr_errno(msg: "Failed to read" , err: -errno); |
196 | |
197 | /* Check the bootconfig magic bytes */ |
198 | if (memcmp(magic, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN) != 0) |
199 | return 0; |
200 | |
201 | if (lseek(fd, -(8 + BOOTCONFIG_MAGIC_LEN), SEEK_END) < 0) |
202 | return pr_errno(msg: "Failed to lseek for size" , err: -errno); |
203 | |
204 | if (read(fd, &size, sizeof(uint32_t)) < 0) |
205 | return pr_errno(msg: "Failed to read size" , err: -errno); |
206 | size = le32toh(size); |
207 | |
208 | if (read(fd, &csum, sizeof(uint32_t)) < 0) |
209 | return pr_errno(msg: "Failed to read checksum" , err: -errno); |
210 | csum = le32toh(csum); |
211 | |
212 | /* Wrong size error */ |
213 | if (stat.st_size < size + 8 + BOOTCONFIG_MAGIC_LEN) { |
214 | pr_err("bootconfig size is too big\n" ); |
215 | return -E2BIG; |
216 | } |
217 | |
218 | if (lseek(fd, stat.st_size - (size + 8 + BOOTCONFIG_MAGIC_LEN), |
219 | SEEK_SET) < 0) |
220 | return pr_errno(msg: "Failed to lseek" , err: -errno); |
221 | |
222 | ret = load_xbc_fd(fd, buf, size); |
223 | if (ret < 0) |
224 | return ret; |
225 | |
226 | /* Wrong Checksum */ |
227 | rcsum = xbc_calc_checksum(data: *buf, size); |
228 | if (csum != rcsum) { |
229 | pr_err("checksum error: %d != %d\n" , csum, rcsum); |
230 | return -EINVAL; |
231 | } |
232 | |
233 | ret = xbc_init(buf: *buf, size, emsg: &msg, NULL); |
234 | /* Wrong data */ |
235 | if (ret < 0) { |
236 | pr_err("parse error: %s.\n" , msg); |
237 | return ret; |
238 | } |
239 | |
240 | return size; |
241 | } |
242 | |
243 | static void show_xbc_error(const char *data, const char *msg, int pos) |
244 | { |
245 | int lin = 1, col, i; |
246 | |
247 | if (pos < 0) { |
248 | pr_err("Error: %s.\n" , msg); |
249 | return; |
250 | } |
251 | |
252 | /* Note that pos starts from 0 but lin and col should start from 1. */ |
253 | col = pos + 1; |
254 | for (i = 0; i < pos; i++) { |
255 | if (data[i] == '\n') { |
256 | lin++; |
257 | col = pos - i; |
258 | } |
259 | } |
260 | pr_err("Parse Error: %s at %d:%d\n" , msg, lin, col); |
261 | |
262 | } |
263 | |
264 | static int init_xbc_with_error(char *buf, int len) |
265 | { |
266 | char *copy = strdup(buf); |
267 | const char *msg; |
268 | int ret, pos; |
269 | |
270 | if (!copy) |
271 | return -ENOMEM; |
272 | |
273 | ret = xbc_init(buf, size: len, emsg: &msg, epos: &pos); |
274 | if (ret < 0) |
275 | show_xbc_error(data: copy, msg, pos); |
276 | free(copy); |
277 | |
278 | return ret; |
279 | } |
280 | |
281 | static int show_xbc(const char *path, bool list) |
282 | { |
283 | int ret, fd; |
284 | char *buf = NULL; |
285 | struct stat st; |
286 | |
287 | ret = stat(path, &st); |
288 | if (ret < 0) { |
289 | ret = -errno; |
290 | pr_err("Failed to stat %s: %d\n" , path, ret); |
291 | return ret; |
292 | } |
293 | |
294 | fd = open(path, O_RDONLY); |
295 | if (fd < 0) { |
296 | ret = -errno; |
297 | pr_err("Failed to open initrd %s: %d\n" , path, ret); |
298 | return ret; |
299 | } |
300 | |
301 | ret = load_xbc_from_initrd(fd, buf: &buf); |
302 | close(fd); |
303 | if (ret < 0) { |
304 | pr_err("Failed to load a boot config from initrd: %d\n" , ret); |
305 | goto out; |
306 | } |
307 | /* Assume a bootconfig file if it is enough small */ |
308 | if (ret == 0 && st.st_size <= XBC_DATA_MAX) { |
309 | ret = load_xbc_file(path, buf: &buf); |
310 | if (ret < 0) { |
311 | pr_err("Failed to load a boot config: %d\n" , ret); |
312 | goto out; |
313 | } |
314 | if (init_xbc_with_error(buf, len: ret) < 0) |
315 | goto out; |
316 | } |
317 | if (list) |
318 | xbc_show_list(); |
319 | else |
320 | xbc_show_compact_tree(); |
321 | ret = 0; |
322 | out: |
323 | free(buf); |
324 | |
325 | return ret; |
326 | } |
327 | |
328 | static int delete_xbc(const char *path) |
329 | { |
330 | struct stat stat; |
331 | int ret = 0, fd, size; |
332 | char *buf = NULL; |
333 | |
334 | fd = open(path, O_RDWR); |
335 | if (fd < 0) { |
336 | ret = -errno; |
337 | pr_err("Failed to open initrd %s: %d\n" , path, ret); |
338 | return ret; |
339 | } |
340 | |
341 | size = load_xbc_from_initrd(fd, buf: &buf); |
342 | if (size < 0) { |
343 | ret = size; |
344 | pr_err("Failed to load a boot config from initrd: %d\n" , ret); |
345 | } else if (size > 0) { |
346 | ret = fstat(fd, &stat); |
347 | if (!ret) |
348 | ret = ftruncate(fd, stat.st_size |
349 | - size - 8 - BOOTCONFIG_MAGIC_LEN); |
350 | if (ret) |
351 | ret = -errno; |
352 | } /* Ignore if there is no boot config in initrd */ |
353 | |
354 | close(fd); |
355 | free(buf); |
356 | |
357 | return ret; |
358 | } |
359 | |
360 | static int apply_xbc(const char *path, const char *xbc_path) |
361 | { |
362 | char *buf, *data, *p; |
363 | size_t total_size; |
364 | struct stat stat; |
365 | const char *msg; |
366 | uint32_t size, csum; |
367 | int pos, pad; |
368 | int ret, fd; |
369 | |
370 | ret = load_xbc_file(path: xbc_path, buf: &buf); |
371 | if (ret < 0) { |
372 | pr_err("Failed to load %s : %d\n" , xbc_path, ret); |
373 | return ret; |
374 | } |
375 | size = strlen(buf) + 1; |
376 | csum = xbc_calc_checksum(data: buf, size); |
377 | |
378 | /* Backup the bootconfig data */ |
379 | data = calloc(size + BOOTCONFIG_ALIGN + |
380 | sizeof(uint32_t) + sizeof(uint32_t) + BOOTCONFIG_MAGIC_LEN, 1); |
381 | if (!data) |
382 | return -ENOMEM; |
383 | memcpy(data, buf, size); |
384 | |
385 | /* Check the data format */ |
386 | ret = xbc_init(buf, size, emsg: &msg, epos: &pos); |
387 | if (ret < 0) { |
388 | show_xbc_error(data, msg, pos); |
389 | free(data); |
390 | free(buf); |
391 | |
392 | return ret; |
393 | } |
394 | printf("Apply %s to %s\n" , xbc_path, path); |
395 | xbc_get_info(node_size: &ret, NULL); |
396 | printf("\tNumber of nodes: %d\n" , ret); |
397 | printf("\tSize: %u bytes\n" , (unsigned int)size); |
398 | printf("\tChecksum: %d\n" , (unsigned int)csum); |
399 | |
400 | /* TODO: Check the options by schema */ |
401 | xbc_exit(); |
402 | free(buf); |
403 | |
404 | /* Remove old boot config if exists */ |
405 | ret = delete_xbc(path); |
406 | if (ret < 0) { |
407 | pr_err("Failed to delete previous boot config: %d\n" , ret); |
408 | free(data); |
409 | return ret; |
410 | } |
411 | |
412 | /* Apply new one */ |
413 | fd = open(path, O_RDWR | O_APPEND); |
414 | if (fd < 0) { |
415 | ret = -errno; |
416 | pr_err("Failed to open %s: %d\n" , path, ret); |
417 | free(data); |
418 | return ret; |
419 | } |
420 | /* TODO: Ensure the @path is initramfs/initrd image */ |
421 | if (fstat(fd, &stat) < 0) { |
422 | ret = -errno; |
423 | pr_err("Failed to get the size of %s\n" , path); |
424 | goto out; |
425 | } |
426 | |
427 | /* To align up the total size to BOOTCONFIG_ALIGN, get padding size */ |
428 | total_size = stat.st_size + size + sizeof(uint32_t) * 2 + BOOTCONFIG_MAGIC_LEN; |
429 | pad = ((total_size + BOOTCONFIG_ALIGN - 1) & (~BOOTCONFIG_ALIGN_MASK)) - total_size; |
430 | size += pad; |
431 | |
432 | /* Add a footer */ |
433 | p = data + size; |
434 | *(uint32_t *)p = htole32(size); |
435 | p += sizeof(uint32_t); |
436 | |
437 | *(uint32_t *)p = htole32(csum); |
438 | p += sizeof(uint32_t); |
439 | |
440 | memcpy(p, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN); |
441 | p += BOOTCONFIG_MAGIC_LEN; |
442 | |
443 | total_size = p - data; |
444 | |
445 | ret = write(fd, data, total_size); |
446 | if (ret < total_size) { |
447 | if (ret < 0) |
448 | ret = -errno; |
449 | pr_err("Failed to apply a boot config: %d\n" , ret); |
450 | if (ret >= 0) |
451 | goto out_rollback; |
452 | } else |
453 | ret = 0; |
454 | |
455 | out: |
456 | close(fd); |
457 | free(data); |
458 | |
459 | return ret; |
460 | |
461 | out_rollback: |
462 | /* Map the partial write to -ENOSPC */ |
463 | if (ret >= 0) |
464 | ret = -ENOSPC; |
465 | if (ftruncate(fd, stat.st_size) < 0) { |
466 | ret = -errno; |
467 | pr_err("Failed to rollback the write error: %d\n" , ret); |
468 | pr_err("The initrd %s may be corrupted. Recommend to rebuild.\n" , path); |
469 | } |
470 | goto out; |
471 | } |
472 | |
473 | static int usage(void) |
474 | { |
475 | printf("Usage: bootconfig [OPTIONS] <INITRD>\n" |
476 | "Or bootconfig <CONFIG>\n" |
477 | " Apply, delete or show boot config to initrd.\n" |
478 | " Options:\n" |
479 | " -a <config>: Apply boot config to initrd\n" |
480 | " -d : Delete boot config file from initrd\n" |
481 | " -l : list boot config in initrd or file\n\n" |
482 | " If no option is given, show the bootconfig in the given file.\n" ); |
483 | return -1; |
484 | } |
485 | |
486 | int main(int argc, char **argv) |
487 | { |
488 | char *path = NULL; |
489 | char *apply = NULL; |
490 | bool delete = false, list = false; |
491 | int opt; |
492 | |
493 | while ((opt = getopt(argc, argv, "hda:l" )) != -1) { |
494 | switch (opt) { |
495 | case 'd': |
496 | delete = true; |
497 | break; |
498 | case 'a': |
499 | apply = optarg; |
500 | break; |
501 | case 'l': |
502 | list = true; |
503 | break; |
504 | case 'h': |
505 | default: |
506 | return usage(); |
507 | } |
508 | } |
509 | |
510 | if ((apply && delete) || (delete && list) || (apply && list)) { |
511 | pr_err("Error: You can give one of -a, -d or -l at once.\n" ); |
512 | return usage(); |
513 | } |
514 | |
515 | if (optind >= argc) { |
516 | pr_err("Error: No initrd is specified.\n" ); |
517 | return usage(); |
518 | } |
519 | |
520 | path = argv[optind]; |
521 | |
522 | if (apply) |
523 | return apply_xbc(path, xbc_path: apply); |
524 | else if (delete) |
525 | return delete_xbc(path); |
526 | |
527 | return show_xbc(path, list); |
528 | } |
529 | |