1 // SPDX-License-Identifier: GPL-2.0
3 * Boot config tool for initrd image
14 #include <linux/kernel.h>
15 #include <linux/bootconfig.h>
17 static int xbc_show_value(struct xbc_node *node)
23 xbc_array_for_each_value(node, val) {
28 printf("%c%s%c%s", q, val, q, node->next ? ", " : ";\n");
34 static void xbc_show_compact_tree(void)
36 struct xbc_node *node, *cnode;
39 node = xbc_root_node();
40 while (node && xbc_node_is_key(node)) {
41 for (i = 0; i < depth; i++)
43 cnode = xbc_node_get_child(node);
44 while (cnode && xbc_node_is_key(cnode) && !cnode->next) {
45 printf("%s.", xbc_node_get_data(node));
47 cnode = xbc_node_get_child(node);
49 if (cnode && xbc_node_is_key(cnode)) {
50 printf("%s {\n", xbc_node_get_data(node));
54 } else if (cnode && xbc_node_is_value(cnode)) {
55 printf("%s = ", xbc_node_get_data(node));
56 xbc_show_value(cnode);
58 printf("%s;\n", xbc_node_get_data(node));
62 node = xbc_node_get_next(node);
66 node = xbc_node_get_parent(node);
69 if (!xbc_node_get_child(node)->next)
72 for (i = 0; i < depth; i++)
76 node = xbc_node_get_next(node);
80 /* Simple real checksum */
81 int checksum(unsigned char *buf, int len)
85 for (i = 0; i < len; i++)
91 #define PAGE_SIZE 4096
93 int load_xbc_fd(int fd, char **buf, int size)
97 *buf = malloc(size + 1);
101 ret = read(fd, *buf, size);
109 /* Return the read size or -errno */
110 int load_xbc_file(const char *path, char **buf)
115 fd = open(path, O_RDONLY);
118 ret = fstat(fd, &stat);
122 ret = load_xbc_fd(fd, buf, stat.st_size);
129 int load_xbc_from_initrd(int fd, char **buf)
133 u32 size = 0, csum = 0, rcsum;
134 char magic[BOOTCONFIG_MAGIC_LEN];
137 ret = fstat(fd, &stat);
141 if (stat.st_size < 8 + BOOTCONFIG_MAGIC_LEN)
144 if (lseek(fd, -BOOTCONFIG_MAGIC_LEN, SEEK_END) < 0) {
145 pr_err("Failed to lseek: %d\n", -errno);
148 if (read(fd, magic, BOOTCONFIG_MAGIC_LEN) < 0)
150 /* Check the bootconfig magic bytes */
151 if (memcmp(magic, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN) != 0)
154 if (lseek(fd, -(8 + BOOTCONFIG_MAGIC_LEN), SEEK_END) < 0) {
155 pr_err("Failed to lseek: %d\n", -errno);
159 if (read(fd, &size, sizeof(u32)) < 0)
162 if (read(fd, &csum, sizeof(u32)) < 0)
165 /* Wrong size error */
166 if (stat.st_size < size + 8 + BOOTCONFIG_MAGIC_LEN) {
167 pr_err("bootconfig size is too big\n");
171 if (lseek(fd, stat.st_size - (size + 8 + BOOTCONFIG_MAGIC_LEN),
173 pr_err("Failed to lseek: %d\n", -errno);
177 ret = load_xbc_fd(fd, buf, size);
182 rcsum = checksum((unsigned char *)*buf, size);
184 pr_err("checksum error: %d != %d\n", csum, rcsum);
188 ret = xbc_init(*buf, &msg, NULL);
191 pr_err("parse error: %s.\n", msg);
198 int show_xbc(const char *path)
203 fd = open(path, O_RDONLY);
205 pr_err("Failed to open initrd %s: %d\n", path, fd);
209 ret = load_xbc_from_initrd(fd, &buf);
211 pr_err("Failed to load a boot config from initrd: %d\n", ret);
214 xbc_show_compact_tree();
223 int delete_xbc(const char *path)
226 int ret = 0, fd, size;
229 fd = open(path, O_RDWR);
231 pr_err("Failed to open initrd %s: %d\n", path, fd);
235 size = load_xbc_from_initrd(fd, &buf);
238 pr_err("Failed to load a boot config from initrd: %d\n", ret);
239 } else if (size > 0) {
240 ret = fstat(fd, &stat);
242 ret = ftruncate(fd, stat.st_size
243 - size - 8 - BOOTCONFIG_MAGIC_LEN);
246 } /* Ignore if there is no boot config in initrd */
254 static void show_xbc_error(const char *data, const char *msg, int pos)
259 pr_err("Error: %s.\n", msg);
263 /* Note that pos starts from 0 but lin and col should start from 1. */
265 for (i = 0; i < pos; i++) {
266 if (data[i] == '\n') {
271 pr_err("Parse Error: %s at %d:%d\n", msg, lin, col);
275 int apply_xbc(const char *path, const char *xbc_path)
283 ret = load_xbc_file(xbc_path, &buf);
285 pr_err("Failed to load %s : %d\n", xbc_path, ret);
288 size = strlen(buf) + 1;
289 csum = checksum((unsigned char *)buf, size);
291 /* Prepare xbc_path data */
292 data = malloc(size + 8);
296 *(u32 *)(data + size) = size;
297 *(u32 *)(data + size + 4) = csum;
299 /* Check the data format */
300 ret = xbc_init(buf, &msg, &pos);
302 show_xbc_error(data, msg, pos);
308 printf("Apply %s to %s\n", xbc_path, path);
309 printf("\tNumber of nodes: %d\n", ret);
310 printf("\tSize: %u bytes\n", (unsigned int)size);
311 printf("\tChecksum: %d\n", (unsigned int)csum);
313 /* TODO: Check the options by schema */
317 /* Remove old boot config if exists */
318 ret = delete_xbc(path);
320 pr_err("Failed to delete previous boot config: %d\n", ret);
326 fd = open(path, O_RDWR | O_APPEND);
328 pr_err("Failed to open %s: %d\n", path, fd);
332 /* TODO: Ensure the @path is initramfs/initrd image */
333 ret = write(fd, data, size + 8);
335 pr_err("Failed to apply a boot config: %d\n", ret);
338 /* Write a magic word of the bootconfig */
339 ret = write(fd, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN);
341 pr_err("Failed to apply a boot config magic: %d\n", ret);
354 printf("Usage: bootconfig [OPTIONS] <INITRD>\n"
355 " Apply, delete or show boot config to initrd.\n"
357 " -a <config>: Apply boot config to initrd\n"
358 " -d : Delete boot config file from initrd\n\n"
359 " If no option is given, show current applied boot config.\n");
363 int main(int argc, char **argv)
370 while ((opt = getopt(argc, argv, "hda:")) != -1) {
384 if (apply && delete) {
385 pr_err("Error: You can not specify both -a and -d at once.\n");
389 if (optind >= argc) {
390 pr_err("Error: No initrd is specified.\n");
397 return apply_xbc(path, apply);
399 return delete_xbc(path);
401 return show_xbc(path);