OpenWrt – Rev 4
?pathlinks?
/*
* imagetag.c
*
* Copyright (C) 2005 Mike Baker
* Copyright (C) 2008 Felix Fietkau <nbd@nbd.name>
* Copyrigth (C) 2010 Daniel Dickinson <openwrt@cshore.neomailbox.net>
*
* 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 <sys/ioctl.h>
#include <mtd/mtd-user.h>
#include "mtd.h"
#include "crc32.h"
#define TAGVER_LEN 4 /* Length of Tag Version */
#define TAGLAYOUT_LEN 4 /* Length of FlashLayoutVer */
#define SIG1_LEN 20 /* Company Signature 1 Length */
#define SIG2_LEN 14 /* Company Signature 2 Length */
#define BOARDID_LEN 16 /* Length of BoardId */
#define ENDIANFLAG_LEN 2 /* Endian Flag Length */
#define CHIPID_LEN 6 /* Chip Id Length */
#define IMAGE_LEN 10 /* Length of Length Field */
#define ADDRESS_LEN 12 /* Length of Address field */
#define DUALFLAG_LEN 2 /* Dual Image flag Length */
#define INACTIVEFLAG_LEN 2 /* Inactie Flag Length */
#define RSASIG_LEN 20 /* Length of RSA Signature in tag */
#define TAGINFO1_LEN 30 /* Length of vendor information field1 in tag */
#define FLASHLAYOUTVER_LEN 4 /* Length of Flash Layout Version String tag */
#define TAGINFO2_LEN 16 /* Length of vendor information field2 in tag */
#define ALTTAGINFO_LEN 54 /* Alternate length for vendor information; Pirelli */
#define NUM_PIRELLI 2
#define IMAGETAG_CRC_START 0xFFFFFFFF
#define PIRELLI_BOARDS { \
"AGPF-S0", \
"DWV-S0", \
}
/*
* The broadcom firmware assumes the rootfs starts the image,
* therefore uses the rootfs start (flash_image_address)
* to determine where to flash the image. Since we have the kernel first
* we have to give it the kernel address, but the crc uses the length
* associated with this address (root_length), which is added to the kernel
* length (kernel_length) to determine the length of image to flash and thus
* needs to be rootfs + deadcode (jffs2 EOF marker)
*/
struct bcm_tag {
/* 0-3: Version of the image tag */
char tag_version[TAGVER_LEN];
/* 4-23: Company Line 1 */
char sig_1[SIG1_LEN];
/* 24-37: Company Line 2 */
char sig_2[SIG2_LEN];
/* 38-43: Chip this image is for */
char chip_id[CHIPID_LEN];
/* 44-59: Board name */
char board_id[BOARDID_LEN];
/* 60-61: Map endianness -- 1 BE 0 LE */
char big_endian[ENDIANFLAG_LEN];
/* 62-71: Total length of image */
char total_length[IMAGE_LEN];
/* 72-83: Address in memory of CFE */
char cfe__address[ADDRESS_LEN];
/* 84-93: Size of CFE */
char cfe_length[IMAGE_LEN];
/* 94-105: Address in memory of image start
* (kernel for OpenWRT, rootfs for stock firmware)
*/
char flash_image_start[ADDRESS_LEN];
/* 106-115: Size of rootfs */
char root_length[IMAGE_LEN];
/* 116-127: Address in memory of kernel */
char kernel_address[ADDRESS_LEN];
/* 128-137: Size of kernel */
char kernel_length[IMAGE_LEN];
/* 138-139: Unused at the moment */
char dual_image[DUALFLAG_LEN];
/* 140-141: Unused at the moment */
char inactive_flag[INACTIVEFLAG_LEN];
/* 142-161: RSA Signature (not used; some vendors may use this) */
char rsa_signature[RSASIG_LEN];
/* 162-191: Compilation and related information (not used in OpenWrt) */
char information1[TAGINFO1_LEN];
/* 192-195: Version flash layout */
char flash_layout_ver[FLASHLAYOUTVER_LEN];
/* 196-199: kernel+rootfs CRC32 */
__u32 fskernel_crc;
/* 200-215: Unused except on Alice Gate where is is information */
char information2[TAGINFO2_LEN];
/* 216-219: CRC32 of image less imagetag (kernel for Alice Gate) */
__u32 image_crc;
/* 220-223: CRC32 of rootfs partition */
__u32 rootfs_crc;
/* 224-227: CRC32 of kernel partition */
__u32 kernel_crc;
/* 228-231: Image sequence number */
char image_sequence[4];
/* 222-235: Openwrt: real rootfs length */
__u32 real_rootfs_length;
/* 236-239: CRC32 of header excluding last 20 bytes */
__u32 header_crc;
/* 240-255: Unused at present */
char reserved2[16];
};
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);
#define CRC_START 0xFFFFFFFF
static uint32_t strntoul(char *str, char **endptr, int base, size_t len) {
char *newstr;
uint32_t res = 0;
newstr = calloc(len + 1, sizeof(char));
if (newstr) {
strncpy(newstr, str, len);
res = strtoul(newstr, endptr, base);
free(newstr);
}
return res;
}
uint32_t compute_crc32(uint32_t crc, off_t start, size_t compute_len, int fd)
{
uint8_t readbuf[1024];
ssize_t res;
off_t offset = start;
/* Read a buffer's worth of bytes */
while (fd && (compute_len >= sizeof(readbuf))) {
res = pread(fd, readbuf, sizeof(readbuf), offset);
crc = crc32(crc, readbuf, res);
compute_len = compute_len - res;
offset += res;
}
/* Less than buffer-size bytes remains, read compute_len bytes */
if (fd && (compute_len > 0)) {
res = pread(fd, readbuf, compute_len, offset);
crc = crc32(crc, readbuf, res);
}
return crc;
}
int
trx_fixup(int fd, const char *name)
{
struct mtd_info_user mtdInfo;
unsigned long len;
void *ptr, *scan;
int bfd;
struct bcm_tag *tag;
ssize_t res;
uint32_t cfelen, imagelen, imagestart, rootfslen;
uint32_t imagecrc, rootfscrc, headercrc;
uint32_t offset = 0;
cfelen = imagelen = imagestart = imagecrc = rootfscrc = headercrc = rootfslen = 0;
if (ioctl(fd, MEMGETINFO, &mtdInfo) < 0) {
fprintf(stderr, "Failed to get mtd info\n");
goto err;
}
len = mtdInfo.size;
if (mtdInfo.size <= 0) {
fprintf(stderr, "Invalid MTD device size\n");
goto err;
}
bfd = mtd_open(name, true);
ptr = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_SHARED, bfd, 0);
if (!ptr || (ptr == (void *) -1)) {
perror("mmap");
goto err1;
}
tag = (struct bcm_tag *) (ptr);
cfelen = strntoul(&tag->cfe_length[0], NULL, 10, IMAGE_LEN);
if (cfelen) {
fprintf(stderr, "Non-zero CFE length. This is currently unsupported.\n");
exit(1);
}
headercrc = compute_crc32(CRC_START, offset, offsetof(struct bcm_tag, header_crc), fd);
if (headercrc != *(uint32_t *)(&tag->header_crc)) {
fprintf(stderr, "Tag verify failed. This may not be a valid image.\n");
exit(1);
}
sprintf(&tag->root_length[0], "%u", 0);
strncpy(&tag->total_length[0], &tag->kernel_length[0], IMAGE_LEN);
imagestart = sizeof(tag);
memcpy(&tag->image_crc, &tag->kernel_crc, sizeof(uint32_t));
memcpy(&tag->fskernel_crc, &tag->kernel_crc, sizeof(uint32_t));
rootfscrc = CRC_START;
memcpy(&tag->rootfs_crc, &rootfscrc, sizeof(uint32_t));
headercrc = crc32(CRC_START, tag, offsetof(struct bcm_tag, header_crc));
memcpy(&tag->header_crc, &headercrc, sizeof(uint32_t));
msync(ptr, sizeof(struct bcm_tag), MS_SYNC|MS_INVALIDATE);
munmap(ptr, len);
close(bfd);
return 0;
err1:
close(bfd);
err:
fprintf(stderr, "Error fixing up imagetag header\n");
return -1;
}
int
trx_check(int imagefd, const char *mtd, char *buf, int *len)
{
struct bcm_tag *tag = (const struct bcm_tag *) buf;
int fd;
uint32_t headerCRC;
uint32_t imageLen;
if (strcmp(mtd, "linux") != 0)
return 1;
*len = read(imagefd, buf, sizeof(struct bcm_tag));
if (*len < sizeof(struct bcm_tag)) {
fprintf(stdout, "Could not get image header, file too small (%d bytes)\n", *len);
return 0;
}
headerCRC = crc32buf(buf, offsetof(struct bcm_tag, header_crc));
if (*(uint32_t *)(&tag->header_crc) != headerCRC) {
if (quiet < 2) {
fprintf(stderr, "Bad header CRC got %08x, calculated %08x\n",
*(uint32_t *)(&tag->header_crc), headerCRC);
fprintf(stderr, "This is not the correct file format; refusing to flash.\n"
"Please specify the correct file or use -f to force.\n");
}
return 0;
}
/* check if image fits to mtd device */
fd = mtd_check_open(mtd);
if(fd < 0) {
fprintf(stderr, "Could not open mtd device: %s\n", mtd);
exit(1);
}
imageLen = strntoul(&tag->total_length[0], NULL, 10, IMAGE_LEN);
if(mtdsize < imageLen) {
fprintf(stderr, "Image too big for partition: %s\n", mtd);
close(fd);
return 0;
}
close(fd);
return 1;
}
int
mtd_fixtrx(const char *mtd, size_t offset, size_t data_size)
{
int fd;
struct bcm_tag *tag;
char *buf;
ssize_t res;
size_t block_offset;
uint32_t cfelen, imagelen, imagestart, rootfslen;
uint32_t imagecrc, rootfscrc, headercrc;
cfelen = imagelen = imagestart = imagecrc = rootfscrc = headercrc = rootfslen = 0;
if (data_size)
fprintf(stderr, "Specifying data size in unsupported for imagetag\n");
if (quiet < 2)
fprintf(stderr, "Trying to fix trx 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(erasesize);
if (!buf) {
perror("malloc");
exit(1);
}
res = pread(fd, buf, erasesize, block_offset);
if (res != erasesize) {
perror("pread");
exit(1);
}
tag = (struct bcm_tag *) (buf + offset);
cfelen = strntoul(tag->cfe_length, NULL, 10, IMAGE_LEN);
if (cfelen) {
fprintf(stderr, "Non-zero CFE length. This is currently unsupported.\n");
exit(1);
}
if (quiet < 2) {
fprintf(stderr, "Verifying we actually have an imagetag.\n");
}
headercrc = compute_crc32(CRC_START, offset, offsetof(struct bcm_tag, header_crc), fd);
if (headercrc != *(uint32_t *)(&tag->header_crc)) {
fprintf(stderr, "Tag verify failed. This may not be a valid image.\n");
exit(1);
}
if (quiet < 2) {
fprintf(stderr, "Checking current fixed status.\n");
}
rootfslen = strntoul(&tag->root_length[0], NULL, 10, IMAGE_LEN);
if (rootfslen == 0) {
if (quiet < 2)
fprintf(stderr, "Header already fixed, exiting\n");
close(fd);
return 0;
}
if (quiet < 2) {
fprintf(stderr, "Setting root length to 0.\n");
}
sprintf(&tag->root_length[0], "%u", 0);
strncpy(&tag->total_length[0], &tag->kernel_length[0], IMAGE_LEN);
if (quiet < 2) {
fprintf(stderr, "Recalculating CRCs.\n");
}
imagestart = sizeof(tag);
memcpy(&tag->image_crc, &tag->kernel_crc, sizeof(uint32_t));
memcpy(&tag->fskernel_crc, &tag->kernel_crc, sizeof(uint32_t));
rootfscrc = CRC_START;
memcpy(&tag->rootfs_crc, &rootfscrc, sizeof(uint32_t));
headercrc = crc32(CRC_START, tag, offsetof(struct bcm_tag, header_crc));
memcpy(&tag->header_crc, &headercrc, sizeof(uint32_t));
if (quiet < 2) {
fprintf(stderr, "Erasing imagetag block\n");
}
if (mtd_erase_block(fd, block_offset)) {
fprintf(stderr, "Can't erase block at 0x%x (%s)\n", block_offset, strerror(errno));
exit(1);
}
if (quiet < 2) {
fprintf(stderr, "New image crc32: 0x%x, rewriting block\n",
*(uint32_t *)(&tag->image_crc));
fprintf(stderr, "New header crc32: 0x%x, rewriting block\n", headercrc);
}
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");
close (fd);
sync();
return 0;
}