--- /dev/null
+/*
+ * imagetag.c
+ *
+ * Copyright (C) 2005 Mike Baker
+ * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
+ * 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-api.h"
+#include "mtd.h"
+#include "crc32.h"
+#include "bcm_tag.h"
+
+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_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, headerCRC));
+ if (*(uint32_t *)(&tag->headerCRC[0]) != headerCRC) {
+
+ if (quiet < 2) {
+ fprintf(stderr, "Bad header CRC got %08lx, calculated %08lx\n",
+ *(uint32_t *)(&tag->headerCRC[0]), 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->totalLength[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)
+{
+ 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 (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->cfeLength[0], 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, headerCRC), fd);
+ if (headercrc != *(uint32_t *)(&tag->headerCRC[0])) {
+ 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->rootLength[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->rootLength[0], "%lu", 0);
+ strncpy(&tag->totalLength[0], &tag->kernelLength[0], IMAGE_LEN);
+
+ if (quiet < 2) {
+ fprintf(stderr, "Recalculating CRCs.\n");
+ }
+
+ imagestart = sizeof(tag);
+ memcpy(&tag->imageCRC[0], &tag->kernelCRC[0], CRC_LEN);
+ memcpy(&tag->fskernelCRC[0], &tag->kernelCRC[0], CRC_LEN);
+ rootfscrc = CRC_START;
+ memcpy(&tag->rootfsCRC[0], &rootfscrc, sizeof(uint32_t));
+ headercrc = crc32(CRC_START, tag, offsetof(struct bcm_tag, headerCRC));
+ memcpy(&tag->headerCRC[0], &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->imageCRC[0]));
+ 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;
+
+}