diff options
Diffstat (limited to 'package/mtd/src/seama.c')
| -rw-r--r-- | package/mtd/src/seama.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/package/mtd/src/seama.c b/package/mtd/src/seama.c new file mode 100644 index 0000000..b0c8bf3 --- /dev/null +++ b/package/mtd/src/seama.c @@ -0,0 +1,179 @@ +/* + * seama.c + * + * Copyright (C) 2011-2012 Gabor Juhos <juhosg@openwrt.org> + * + * Based on the trx fixup code: + * Copyright (C) 2005 Mike Baker + * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <stddef.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/mman.h> +#include <sys/stat.h> +#include <string.h> +#include <errno.h> +#include <arpa/inet.h> + +#include <sys/ioctl.h> +#include <mtd/mtd-user.h> +#include "mtd.h" +#include "seama.h" +#include "md5.h" + +#if __BYTE_ORDER == __BIG_ENDIAN +#define STORE32_LE(X) ((((X) & 0x000000FF) << 24) | (((X) & 0x0000FF00) << 8) | (((X) & 0x00FF0000) >> 8) | (((X) & 0xFF000000) >> 24)) +#elif __BYTE_ORDER == __LITTLE_ENDIAN +#define STORE32_LE(X) (X) +#else +#error unknown endianness! +#endif + +ssize_t pread(int fd, void *buf, size_t count, off_t offset); +ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset); + +int +seama_fix_md5(char *buf, size_t len) +{ + struct seama_hdr *shdr; + char *data; + size_t msize; + size_t isize; + MD5_CTX ctx; + unsigned char digest[16]; + int i; + + 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; + } + + isize = ntohl(shdr->size); + msize = ntohs(shdr->metasize); + if (isize == 0) { + /* the image contains no checksum */ + return -1; + } + + 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_Final(digest, &ctx); + + if (!memcmp(digest, &buf[sizeof(struct seama_hdr)], 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); + for (i = 0; i < sizeof(digest); i++) + fprintf(stderr, "%02x", digest[i]); + + fprintf(stderr, "\n"); + } + + /* update the size in the image */ + shdr->size = htonl(isize); + + /* update the checksum in the image */ + for (i = 0; i < sizeof(digest); i++) + buf[sizeof(struct seama_hdr) + i] = digest[i]; + + return 0; +} + +int +mtd_fixseama(const char *mtd, size_t offset) +{ + int fd; + char *buf; + ssize_t res; + size_t block_offset; + + if (quiet < 2) + fprintf(stderr, "Trying to fix SEAMA header in %s at 0x%x...\n", + mtd, offset); + + block_offset = offset & ~(erasesize - 1); + offset -= block_offset; + + fd = mtd_check_open(mtd); + if(fd < 0) { + fprintf(stderr, "Could not open mtd device: %s\n", mtd); + exit(1); + } + + if (block_offset + erasesize > mtdsize) { + fprintf(stderr, "Offset too large, device size 0x%x\n", + mtdsize); + exit(1); + } + + buf = malloc(mtdsize); + if (!buf) { + perror("malloc"); + exit(1); + } + + res = pread(fd, buf, mtdsize, block_offset); + if (res != mtdsize) { + perror("pread"); + exit(1); + } + + if (seama_fix_md5(buf, mtdsize)) + goto out; + + if (mtd_erase_block(fd, block_offset)) { + fprintf(stderr, "Can't erease block at 0x%x (%s)\n", + block_offset, strerror(errno)); + exit(1); + } + + if (quiet < 2) + fprintf(stderr, "Rewriting block at 0x%x\n", block_offset); + + if (pwrite(fd, buf, erasesize, block_offset) != erasesize) { + fprintf(stderr, "Error writing block (%s)\n", strerror(errno)); + exit(1); + } + + if (quiet < 2) + fprintf(stderr, "Done.\n"); + +out: + close (fd); + sync(); + + return 0; +} + |