+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->cfeLength[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, headerCRC), fd);
+ if (headercrc != *(uint32_t *)(&tag->headerCRC[0])) {
+ fprintf(stderr, "Tag verify failed. This may not be a valid image.\n");
+ exit(1);
+ }
+
+ sprintf(&tag->rootLength[0], "%lu", 0);
+ strncpy(&tag->totalLength[0], &tag->kernelLength[0], IMAGE_LEN);
+
+ 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));
+
+ 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;
+}
+
+