1/* 2 * Thanks to Vassily Galinsky for this tool 3***************************************************************************** 4AIRLINK AR525W firmware image structure 5 -8:-5 Extended (httpd) header checksum - sum2 6 -4:-1 Extended (httpd) header magic - "ARRN" - 0x4e525241 7 0: 3 Standard (tftpd) header magic - "GMTK" - 0x4b544d47 8 4: 7 Standard (tftpd) header checksum - sum1 9 8: b 0 10 c: f Size of compressed linux kernel 11 10:13 Size of firmware image file with standard header 12 14:17 Product code - 0x5 13 18:1b Bootloader checksum - sum0 14 1c:1f 0 15 20: Compressed linux kernel 16 - Squashfs or jffs2 file system - kernel dependent - either 32 bytes or sector aligned 17*****************************************************************************/ 18#include <stdio.h> 19#include <stdlib.h> 20#include <string.h> 21#include <unistd.h> 22#include <sys/mman.h> 23#include <sys/types.h> 24#include <sys/stat.h> 25#include <fcntl.h> 26#include <netinet/in.h> 27 28typedef unsigned char uchar; 29 30uint32_t crctab[257] = { 31 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 32 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3, 33 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 34 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 35 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 36 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 37 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 38 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5, 39 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 40 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 41 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 42 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 43 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 44 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f, 45 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 46 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 47 0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 48 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 49 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 50 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 51 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 52 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 53 0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 54 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 55 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 56 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 57 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 58 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 59 0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 60 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 61 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 62 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 63 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 64 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 65 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 66 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 67 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 68 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7, 69 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 70 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 71 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 72 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 73 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 74 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79, 75 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 76 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 77 0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 78 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 79 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 80 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 81 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 82 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 83 0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 84 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 85 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 86 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 87 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 88 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 89 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 90 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 91 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 92 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf, 93 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 94 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d, 95 0 96}; 97 98uint32_t header[] = { 99 0x00000000, 0x4e525241, 100 0x4b544d47, 0x00000000, 0x00000000, 0x000afd4a, 101 0x00000000, 0x00000005, 0x00000000, 0x00000000 102}; 103 104static int JFFS2 = 0; 105 106int generate_image(char *kname, char *fsname, char *fname, int EHDR) 107{ 108 int i; 109 uint32_t lenk, lens; 110 uchar *bk, *bs; 111 int fkd, ffd, fsd; 112 fkd = open(kname, O_RDONLY); 113 ffd = creat(fname, 0644); 114 if ((fkd < 0) || (ffd < 0)) 115 return -1; 116 if (fsname) { 117 fsd = open(fsname, O_RDONLY); 118 if (fsd < 0) 119 return -1; 120 } 121 lenk = lseek(fkd, 0, SEEK_END); 122 header[5] = lenk; 123 bk = (uchar *) mmap(NULL, lenk, PROT_READ, MAP_SHARED, fkd, 0); 124 if (bk == MAP_FAILED) 125 return -1; 126 if (fsname) { 127 lens = lseek(fsd, 0, SEEK_END); 128 bs = (uchar *) mmap(NULL, lens, PROT_READ, MAP_SHARED, fsd, 129 0); 130 if (bs == MAP_FAILED) 131 return -1; 132 } 133 if (EHDR) 134 write(ffd, header, 0x28); 135 else 136 write(ffd, header + 2, 0x20); 137 write(ffd, bk, lenk); 138 lenk += 0x20; 139 if (!JFFS2) JFFS2 = 0x20; 140 printf("Padding header+kernel - 0x%x + 0x%x = 0x%x\n", 141 lenk, ((lenk - 1 + JFFS2) / JFFS2) * JFFS2 - lenk, 142 ((lenk - 1 + JFFS2) / JFFS2) * JFFS2); 143 for (i = 0; i < ((lenk - 1 + JFFS2) / JFFS2) * JFFS2 - lenk; i++) 144 write(ffd, header, 1); 145 if (fsname) { 146 write(ffd, bs, lens); 147 close(fsd); 148 } 149 close(ffd); 150 close(fkd); 151 return 0; 152} 153 154uint32_t crc32(uchar * buf, uint32_t len) 155{ 156 register int i; 157 uint32_t sum; 158 register uint32_t s0; 159 s0 = ~0; 160 for (i = 0; i < len; i++) { 161 s0 = (s0 >> 8) ^ crctab[(uchar) (s0 & 0xFF) ^ buf[i]]; 162 } 163 sum = ~s0; 164 return sum; 165} 166 167void usage(char *prog) 168{ 169 printf("Usage: %s [-b 0/1] image_filename \n", prog); 170 printf(" update checksums for firmware file\n"); 171 printf 172 ("Usage: %s [-b 0/1] [-j erasesize_in_kibytes] [-e] kernel filesystem image_filename \n", 173 prog); 174 printf(" generate firmware file and update checksums\n"); 175 printf("--------------------------------------------------\n"); 176 printf(" -e - generate header for web upload\n"); 177 printf(" -b 0/1 - clear/update bootloader checksum\n"); 178 printf(" -j erasesize_in_kibytes - generate header for jffs2 filesystem\n"); 179} 180 181int main(int argc, char **argv) 182{ 183 uchar b[0x400]; 184 char EHDR = 0; 185 char BHDR = 0; 186 int c, fd; 187 extern char *optarg; 188 extern int optind, optopt; 189 190 while ((c = getopt(argc, argv, "b:ej:")) != -1) { 191 switch (c) { 192 case 'b': 193 if (optarg[0] == '1') 194 BHDR = 1; 195 break; 196 case 'e': 197 EHDR = 1; 198 break; 199 case 'j': 200 sscanf(optarg, "%i", &JFFS2); 201 JFFS2 *= 1024; 202 break; 203 case '?': 204 fprintf(stderr, "\nError: unknown arg %c\n\n\n", 205 optopt); 206 usage(argv[0]); 207 exit(-1); 208 } 209 } 210 if (((argc - optind) < 1) && ((argc - optind) > 3)) { 211 usage(argv[0]); 212 exit(-1); 213 } 214 if ((argc - optind) == 3) 215 if (generate_image 216 (argv[optind], argv[optind + 1], argv[optind + 2], 217 EHDR)) { 218 fprintf(stderr, 219 "\nError generating image file %s\n\n\n", 220 argv[argc - 1]); 221 usage(argv[0]); 222 exit(-1); 223 } 224 if ((argc - optind) == 2) 225 if (generate_image 226 (argv[optind], NULL, argv[optind + 1], EHDR)) { 227 fprintf(stderr, 228 "\nError generating image file %s\n\n\n", 229 argv[argc - 1]); 230 usage(argv[0]); 231 exit(-1); 232 } 233 234 fd = open(argv[argc - 1], O_RDWR); 235 if (fd < 0) { 236 fprintf(stderr, "\nImage file not found %s\n\n\n", 237 argv[argc - 1]); 238 usage(argv[0]); 239 exit(-1); 240 } 241 long i, len = lseek(fd, 0, SEEK_END); 242 lseek(fd, 0, SEEK_SET); 243 uchar *buf = malloc(len); 244 read(fd, buf, len); 245 uint32_t sum, l0; 246 uint32_t MagicS = 0x474d544b; 247 uint32_t MagicE = 0x4152524e; 248 if (ntohl(*((uint32_t *) buf)) == MagicS) { 249 fprintf(stderr, 250 "Image without extra 8 bytes - Standard header\n"); 251 buf[0x10] = len & 0xff; 252 buf[0x11] = (len >> 8) & 0xff; 253 buf[0x12] = (len >> 16) & 0xff; 254 buf[0x13] = (len >> 24) & 0xff; 255 lseek(fd, 0x10, SEEK_SET); 256 write(fd, buf + 0x10, 0x4); 257 EHDR = 0; 258 } else if ((ntohl(*((uint32_t *) (buf + 0x8))) == MagicS) 259 && ((ntohl(*((uint32_t *) (buf + 0x4))) == MagicE))) { 260 fprintf(stderr, 261 "Image with extra 8 bytes - Extended header\n"); 262 *((uint32_t *) (buf + 0x18)) = len - 8; 263 buf[0x18] = (len - 8) & 0xff; 264 buf[0x19] = ((len - 8) >> 8) & 0xff; 265 buf[0x1a] = ((len - 8) >> 16) & 0xff; 266 buf[0x1b] = ((len - 8) >> 24) & 0xff; 267 lseek(fd, 0x18, SEEK_SET); 268 write(fd, buf + 0x18, 0x4); 269 buf += 8; 270 EHDR = 1; 271 } else if (len == buf[0x10] | ((uint32_t)buf[0x11] << 8) | ((uint32_t)buf[0x12] << 16) | ((uint32_t)buf[0x13] << 24)) { 272 fprintf(stderr, 273 "Image without extra 8 bytes - Standard header\n"); 274 EHDR = 0; 275 } else if (len == (buf[0x18] | ((uint32_t)buf[0x19] << 8) | ((uint32_t)buf[0x1a] << 16) | ((uint32_t)buf[0x1b] << 24)) + 8) { 276 fprintf(stderr, 277 "Image with extra 8 bytes - Extended header\n"); 278 buf += 8; 279 EHDR = 1; 280 } else { 281 fprintf(stderr, "ERROR: Wrong image size\n"); 282 exit(-1); 283 } 284 l0 = buf[0x10] | ((uint32_t)buf[0x11] << 8) | ((uint32_t)buf[0x12] << 16) | ((uint32_t)buf[0x13] << 24); 285 if (!BHDR) 286 *((uint32_t *) & buf[0x18]) = 0; 287 unsigned long sum0 = buf[0x18] | ((uint32_t)buf[0x19] << 8) | ((uint32_t)buf[0x1a] << 16) | ((uint32_t)buf[0x1b] << 24); 288 unsigned long sum1 = buf[0x4] | ((uint32_t)buf[0x5] << 8) | ((uint32_t)buf[0x6] << 16) | ((uint32_t)buf[0x7] << 24); 289 *((uint32_t *) & buf[0x4]) = 0x0L; 290 memcpy(b, buf, 0x100); 291 memcpy(b + 0x100, buf + ((l0 >> 1) - ((l0 & 0x6) >> 1)), 0x100); 292 memcpy(b + 0x200, buf + (l0 - 0x200), 0x200); 293 *((uint32_t *) & b[0x18]) = 0x0L; 294 295 sum = crc32(b, 0x400); 296 printf("CRC32 sum0 - (%x, %x, %x)\n", sum, sum0, 0x400); 297 if (EHDR) 298 lseek(fd, 0x20, SEEK_SET); 299 else 300 lseek(fd, 0x18, SEEK_SET); 301 buf[0x18] = (BHDR ? sum : sum0) & 0xff; 302 buf[0x19] = ((BHDR ? sum : sum0) >> 8) & 0xff; 303 buf[0x1a] = ((BHDR ? sum : sum0) >> 16) & 0xff; 304 buf[0x1b] = ((BHDR ? sum : sum0) >> 24) & 0xff; 305 write(fd, &buf[0x18], 0x4); 306 307 sum = crc32(buf, l0); 308 printf("CRC32 sum1 - (%x, %x, %x)\n", sum, sum1, l0); 309 if (EHDR) 310 lseek(fd, 0xC, SEEK_SET); 311 else 312 lseek(fd, 0x4, SEEK_SET); 313 buf[0x4] = sum & 0xff; 314 buf[0x5] = (sum >> 8) & 0xff; 315 buf[0x6] = (sum >> 16) & 0xff; 316 buf[0x7] = (sum >> 24) & 0xff; 317 write(fd, &buf[0x4], 0x4); 318 if (EHDR) { 319 unsigned long sum2 = buf[-0x8] | ((uint32_t)buf[-0x7] << 8) | ((uint32_t)buf[-0x6] << 16) | ((uint32_t)buf[-0x5] << 24); 320 *((uint32_t *) & buf[-0x8]) = 0L; 321 sum = crc32(buf - 0x4, len - 0x4); 322 printf("CRC32 sum2 - (%x, %x, %x)\n", sum, sum2, 323 len - 0x4); 324 lseek(fd, 0, SEEK_SET); 325 *((uint32_t *) & buf[-0x8]) = htonl(sum); 326 write(fd, &buf[-0x8], 0x4); 327 buf -= 8; 328 } 329 close(fd); 330 free(buf); 331 return 0; 332} 333