ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset);
int
-seama_fix_md5(char *buf, size_t len)
+seama_fix_md5(struct seama_entity_header *shdr, int fd, size_t data_offset, size_t data_size)
{
- struct seama_hdr *shdr;
- char *data;
- size_t msize;
- size_t isize;
+ char *buf;
+ ssize_t res;
MD5_CTX ctx;
unsigned char digest[16];
int i;
+ int err = 0;
- if (len < sizeof(struct seama_hdr))
- return -1;
-
- shdr = (struct seama_hdr *) buf;
- if (shdr->magic != htonl(SEAMA_MAGIC)) {
- fprintf(stderr, "no SEAMA header found\n");
- return -1;
+ buf = malloc(data_size);
+ if (!buf) {
+ err = -ENOMEM;
+ goto err_out;
}
- isize = ntohl(shdr->size);
- msize = ntohs(shdr->metasize);
- if (isize == 0) {
- /* the image contains no checksum */
- return -1;
+ res = pread(fd, buf, data_size, data_offset);
+ if (res != data_size) {
+ perror("pread");
+ err = -EIO;
+ goto err_free;
}
- len -= sizeof(struct seama_hdr) + sizeof(digest) + msize;
- if (isize > len)
- isize = len;
-
- data = buf + sizeof(struct seama_hdr) + sizeof(digest) + msize;
-
MD5_Init(&ctx);
- MD5_Update(&ctx, data, isize);
+ MD5_Update(&ctx, buf, data_size);
MD5_Final(digest, &ctx);
- if (!memcmp(digest, &buf[sizeof(struct seama_hdr)], sizeof(digest))) {
+ if (!memcmp(digest, shdr->md5, sizeof(digest))) {
if (quiet < 2)
fprintf(stderr, "the header is fixed already\n");
return -1;
}
if (quiet < 2) {
- fprintf(stderr, "new size:%u, new MD5: ", isize);
+ fprintf(stderr, "new size:%u, new MD5: ", data_size);
for (i = 0; i < sizeof(digest); i++)
fprintf(stderr, "%02x", digest[i]);
}
/* update the size in the image */
- shdr->size = htonl(isize);
+ shdr->size = htonl(data_size);
/* update the checksum in the image */
- for (i = 0; i < sizeof(digest); i++)
- buf[sizeof(struct seama_hdr) + i] = digest[i];
+ memcpy(shdr->md5, digest, sizeof(digest));
- return 0;
+err_free:
+ free(buf);
+err_out:
+ return err;
}
int
mtd_fixseama(const char *mtd, size_t offset)
{
int fd;
- char *buf;
+ char *first_block;
ssize_t res;
size_t block_offset;
+ size_t data_offset;
+ size_t data_size;
+ struct seama_entity_header *shdr;
if (quiet < 2)
fprintf(stderr, "Trying to fix SEAMA header in %s at 0x%x...\n",
exit(1);
}
- buf = malloc(mtdsize);
- if (!buf) {
+ first_block = malloc(erasesize);
+ if (!first_block) {
perror("malloc");
exit(1);
}
- res = pread(fd, buf, mtdsize, block_offset);
- if (res != mtdsize) {
+ res = pread(fd, first_block, erasesize, block_offset);
+ if (res != erasesize) {
perror("pread");
exit(1);
}
- if (seama_fix_md5(buf, mtdsize))
+ shdr = (struct seama_entity_header *)(first_block + offset);
+ if (shdr->magic != htonl(SEAMA_MAGIC)) {
+ fprintf(stderr, "No SEAMA header found\n");
+ exit(1);
+ } else if (!ntohl(shdr->size)) {
+ fprintf(stderr, "Seama entity with empty image\n");
+ exit(1);
+ }
+
+ data_offset = offset + sizeof(struct seama_entity_header) + ntohs(shdr->metasize);
+ data_size = mtdsize - data_offset;
+ if (data_size > ntohl(shdr->size))
+ data_size = ntohl(shdr->size);
+ if (seama_fix_md5(shdr, fd, data_offset, data_size))
goto out;
if (mtd_erase_block(fd, block_offset)) {
if (quiet < 2)
fprintf(stderr, "Rewriting block at 0x%x\n", block_offset);
- if (pwrite(fd, buf, erasesize, block_offset) != erasesize) {
+ if (pwrite(fd, first_block, erasesize, block_offset) != erasesize) {
fprintf(stderr, "Error writing block (%s)\n", strerror(errno));
exit(1);
}