529 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * Boot config tool for initrd image4 */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 19static 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 else30 q = '"';31 printf("%c%s%c%s", q, val, q, xbc_node_is_array(node) ? ", " : eol);32 i++;33 }34 return i;35}36 37static 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(cnode) && !cnode->next) {49 vnode = xbc_node_get_child(cnode);50 /*51 * If @cnode has value and subkeys, this52 * 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(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(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(cnode)) {74 printf("%s = ", xbc_node_get_data(node));75 xbc_show_value(cnode, true);76 /*77 * If @node has value and subkeys, continue78 * looping on subkeys with same node.79 */80 if (cnode->next) {81 cnode = xbc_node_get_next(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 110static 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(leaf, 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(xbc_node_get_child(leaf), false);129 }130}131 132#define PAGE_SIZE 4096133 134static 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 */151static 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, stat.st_size);164 165 close(fd);166 167 return ret;168}169 170static int pr_errno(const char *msg, int err)171{172 pr_err("%s: %d\n", msg, err);173 return err;174}175 176static 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("Failed to lseek for magic", -errno);193 194 if (read(fd, magic, BOOTCONFIG_MAGIC_LEN) < 0)195 return pr_errno("Failed to read", -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("Failed to lseek for size", -errno);203 204 if (read(fd, &size, sizeof(uint32_t)) < 0)205 return pr_errno("Failed to read size", -errno);206 size = le32toh(size);207 208 if (read(fd, &csum, sizeof(uint32_t)) < 0)209 return pr_errno("Failed to read checksum", -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("Failed to lseek", -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(*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, size, &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 243static 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 264static 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, len, &msg, &pos);274 if (ret < 0)275 show_xbc_error(copy, msg, pos);276 free(copy);277 278 return ret;279}280 281static 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);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);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, ret) < 0)315 goto out;316 }317 if (list)318 xbc_show_list();319 else320 xbc_show_compact_tree();321 ret = 0;322out:323 free(buf);324 325 return ret;326}327 328static 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);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_size349 - 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 360static 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(xbc_path, &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(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, &msg, &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(&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 } else453 ret = 0;454 455out:456 close(fd);457 free(data);458 459 return ret;460 461out_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 473static 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 486int 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, apply);524 else if (delete)525 return delete_xbc(path);526 527 return show_xbc(path, list);528}529