developer | fc05f9d | 2022-05-06 13:09:53 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | |
| 3 | /* |
| 4 | * wrgg.c |
| 5 | * |
| 6 | * Copyright (C) 2005 Mike Baker |
| 7 | * Copyright (C) 2008 Felix Fietkau <nbd@nbd.name> |
| 8 | * Copyright (C) 2011-2012 Gabor Juhos <juhosg@openwrt.org> |
| 9 | * Copyright (C) 2016 Stijn Tintel <stijn@linux-ipv6.be> |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License |
| 13 | * as published by the Free Software Foundation; either version 2 |
| 14 | * of the License, or (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 24 | */ |
| 25 | |
| 26 | #include <endian.h> |
| 27 | #include <stdio.h> |
| 28 | #include <stdlib.h> |
| 29 | #include <stddef.h> |
| 30 | #include <unistd.h> |
| 31 | #include <fcntl.h> |
| 32 | #include <sys/mman.h> |
| 33 | #include <sys/stat.h> |
| 34 | #include <string.h> |
| 35 | #include <errno.h> |
| 36 | #include <arpa/inet.h> |
| 37 | |
| 38 | #include <sys/ioctl.h> |
| 39 | #include <mtd/mtd-user.h> |
| 40 | #include "mtd.h" |
| 41 | #include "wrgg.h" |
| 42 | #include "md5.h" |
| 43 | |
| 44 | static inline uint32_t le32_to_cpu(uint8_t *buf) |
| 45 | { |
| 46 | return buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24; |
| 47 | } |
| 48 | |
| 49 | ssize_t pread(int fd, void *buf, size_t count, off_t offset); |
| 50 | ssize_t pwrite(int fd, const void *buf, size_t count, off_t offset); |
| 51 | |
| 52 | int |
| 53 | wrgg_fix_md5(struct wrgg03_header *shdr, int fd, size_t data_offset, size_t data_size) |
| 54 | { |
| 55 | char *buf; |
| 56 | ssize_t res; |
| 57 | MD5_CTX ctx; |
| 58 | unsigned char digest[16]; |
| 59 | int i; |
| 60 | int err = 0; |
| 61 | |
| 62 | buf = malloc(data_size); |
| 63 | if (!buf) { |
| 64 | err = -ENOMEM; |
| 65 | goto err_out; |
| 66 | } |
| 67 | |
| 68 | res = pread(fd, buf, data_size, data_offset); |
| 69 | if (res != data_size) { |
| 70 | perror("pread"); |
| 71 | err = -EIO; |
| 72 | goto err_free; |
| 73 | } |
| 74 | |
| 75 | MD5_Init(&ctx); |
| 76 | MD5_Update(&ctx, (char *)&shdr->offset, sizeof(shdr->offset)); |
| 77 | MD5_Update(&ctx, (char *)&shdr->dev_name, sizeof(shdr->dev_name)); |
| 78 | MD5_Update(&ctx, buf, data_size); |
| 79 | MD5_Final(digest, &ctx); |
| 80 | |
| 81 | if (!memcmp(digest, shdr->digest, sizeof(digest))) { |
| 82 | if (quiet < 2) |
| 83 | fprintf(stderr, "the header is fixed already\n"); |
| 84 | return -1; |
| 85 | } |
| 86 | |
| 87 | if (quiet < 2) { |
| 88 | fprintf(stderr, "new size:%u, new MD5: ", data_size); |
| 89 | for (i = 0; i < sizeof(digest); i++) |
| 90 | fprintf(stderr, "%02x", digest[i]); |
| 91 | |
| 92 | fprintf(stderr, "\n"); |
| 93 | } |
| 94 | |
| 95 | /* update the size in the image */ |
| 96 | shdr->size = data_size; |
| 97 | |
| 98 | /* update the checksum in the image */ |
| 99 | memcpy(shdr->digest, digest, sizeof(digest)); |
| 100 | |
| 101 | err_free: |
| 102 | free(buf); |
| 103 | err_out: |
| 104 | return err; |
| 105 | } |
| 106 | |
| 107 | int |
| 108 | mtd_fixwrgg(const char *mtd, size_t offset, size_t data_size) |
| 109 | { |
| 110 | int fd; |
| 111 | char *first_block; |
| 112 | ssize_t res; |
| 113 | size_t block_offset; |
| 114 | size_t data_offset; |
| 115 | struct wrgg03_header *shdr; |
| 116 | |
| 117 | if (quiet < 2) |
| 118 | fprintf(stderr, "Trying to fix WRGG header in %s at 0x%x...\n", |
| 119 | mtd, offset); |
| 120 | |
| 121 | block_offset = offset & ~(erasesize - 1); |
| 122 | offset -= block_offset; |
| 123 | |
| 124 | fd = mtd_check_open(mtd); |
| 125 | if(fd < 0) { |
| 126 | fprintf(stderr, "Could not open mtd device: %s\n", mtd); |
| 127 | exit(1); |
| 128 | } |
| 129 | |
| 130 | if (block_offset + erasesize > mtdsize) { |
| 131 | fprintf(stderr, "Offset too large, device size 0x%x\n", |
| 132 | mtdsize); |
| 133 | exit(1); |
| 134 | } |
| 135 | |
| 136 | first_block = malloc(erasesize); |
| 137 | if (!first_block) { |
| 138 | perror("malloc"); |
| 139 | exit(1); |
| 140 | } |
| 141 | |
| 142 | res = pread(fd, first_block, erasesize, block_offset); |
| 143 | if (res != erasesize) { |
| 144 | perror("pread"); |
| 145 | exit(1); |
| 146 | } |
| 147 | |
| 148 | shdr = (struct wrgg03_header *)(first_block + offset); |
| 149 | |
| 150 | /* The magic is always stored in little-endian byte order */ |
| 151 | if (le32_to_cpu((uint8_t *)&shdr->magic1) != WRGG03_MAGIC) { |
| 152 | fprintf(stderr, "magic1 = %x\n", shdr->magic1); |
| 153 | fprintf(stderr, "WRGG03_MAGIC = %x\n", WRGG03_MAGIC); |
| 154 | fprintf(stderr, "No WRGG header found\n"); |
| 155 | exit(1); |
| 156 | } else if (!shdr->size) { |
| 157 | fprintf(stderr, "WRGG entity with empty image\n"); |
| 158 | exit(1); |
| 159 | } |
| 160 | |
| 161 | data_offset = offset + sizeof(struct wrgg03_header); |
| 162 | if (!data_size) |
| 163 | data_size = mtdsize - data_offset; |
| 164 | if (data_size > shdr->size) |
| 165 | data_size = shdr->size; |
| 166 | if (wrgg_fix_md5(shdr, fd, data_offset, data_size)) |
| 167 | goto out; |
| 168 | |
| 169 | if (mtd_erase_block(fd, block_offset)) { |
| 170 | fprintf(stderr, "Can't erease block at 0x%x (%s)\n", |
| 171 | block_offset, strerror(errno)); |
| 172 | exit(1); |
| 173 | } |
| 174 | |
| 175 | if (quiet < 2) |
| 176 | fprintf(stderr, "Rewriting block at 0x%x\n", block_offset); |
| 177 | |
| 178 | if (pwrite(fd, first_block, erasesize, block_offset) != erasesize) { |
| 179 | fprintf(stderr, "Error writing block (%s)\n", strerror(errno)); |
| 180 | exit(1); |
| 181 | } |
| 182 | |
| 183 | if (quiet < 2) |
| 184 | fprintf(stderr, "Done.\n"); |
| 185 | |
| 186 | out: |
| 187 | close (fd); |
| 188 | sync(); |
| 189 | |
| 190 | return 0; |
| 191 | } |