src/mktplinkfw.c

   1 /*
   2  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   3  *
   4  * This tool was based on:
   5  *   TP-Link WR941 V2 firmware checksum fixing tool.
   6  *   Copyright (C) 2008,2009 Wang Jian <lark@linux.net.cn>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License version 2 as published
  10  * by the Free Software Foundation.
  11  *
  12  */
  13
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <stdint.h>
  17 #include <string.h>
  18 #include <unistd.h>     /* for unlink() */
  19 #include <libgen.h>
  20 #include <getopt.h>     /* for getopt() */
  21 #include <stdarg.h>
  22 #include <stdbool.h>
  23 #include <endian.h>
  24 #include <errno.h>
  25 #include <sys/stat.h>
  26
  27 #include <arpa/inet.h>
  28 #include <netinet/in.h>
  29
  30 #include "md5.h"
  31 #include "mktplinkfw-lib.h"
  32
  33 #define HEADER_VERSION_V1       0x01000000
  34 #define HEADER_VERSION_V2       0x02000000
  35
  36 struct fw_header {
  37         uint32_t        version;        /* header version */
  38         char            vendor_name[24];
  39         char            fw_version[36];
  40         uint32_t        hw_id;          /* hardware id */
  41         uint32_t        hw_rev;         /* hardware revision */
  42         uint32_t        region_code;    /* region code */
  43         uint8_t         md5sum1[MD5SUM_LEN];
  44         uint32_t        unk2;
  45         uint8_t         md5sum2[MD5SUM_LEN];
  46         uint32_t        unk3;
  47         uint32_t        kernel_la;      /* kernel load address */
  48         uint32_t        kernel_ep;      /* kernel entry point */
  49         uint32_t        fw_length;      /* total length of the firmware */
  50         uint32_t        kernel_ofs;     /* kernel data offset */
  51         uint32_t        kernel_len;     /* kernel data length */
  52         uint32_t        rootfs_ofs;     /* rootfs data offset */
  53         uint32_t        rootfs_len;     /* rootfs data length */
  54         uint32_t        boot_ofs;       /* bootloader data offset */
  55         uint32_t        boot_len;       /* bootloader data length */
  56         uint16_t        ver_hi;
  57         uint16_t        ver_mid;
  58         uint16_t        ver_lo;
  59         uint8_t         pad[130];
  60         char            region_str1[32];
  61         char            region_str2[32];
  62         uint8_t         pad2[160];
  63 } __attribute__ ((packed));
  64
  65 struct fw_region {
  66         char            name[4];
  67         uint32_t        code;
  68 };
  69
  70
  71 /*
  72  * Globals
  73  */
  74 char *ofname;
  75 char *progname;
  76 static char *vendor = "TP-LINK Technologies";
  77 static char *version = "ver. 1.0";
  78 static char *fw_ver = "0.0.0";
  79 static uint32_t hdr_ver = HEADER_VERSION_V1;
  80
  81 static char *layout_id;
  82 struct flash_layout *layout;
  83 static char *opt_hw_id;
  84 static uint32_t hw_id;
  85 static char *opt_hw_rev;
  86 static uint32_t hw_rev;
  87 static uint32_t opt_hdr_ver = 1;
  88 static char *country;
  89 static const struct fw_region *region;
  90 static int fw_ver_lo;
  91 static int fw_ver_mid;
  92 static int fw_ver_hi;
  93 struct file_info kernel_info;
  94 static uint32_t kernel_la = 0;
  95 static uint32_t kernel_ep = 0;
  96 uint32_t kernel_len = 0;
  97 struct file_info rootfs_info;
  98 uint32_t rootfs_ofs = 0;
  99 uint32_t rootfs_align;
 100 static struct file_info boot_info;
 101 int combined;
 102 int strip_padding;
 103 int add_jffs2_eof;
 104 static uint32_t fw_max_len;
 105 static uint32_t reserved_space;
 106
 107 static struct file_info inspect_info;
 108 static int extract = 0;
 109 static bool endian_swap = false;
 110 static bool rootfs_ofs_calc = false;
 111
 112 static const char md5salt_normal[MD5SUM_LEN] = {
 113         0xdc, 0xd7, 0x3a, 0xa5, 0xc3, 0x95, 0x98, 0xfb,
 114         0xdd, 0xf9, 0xe7, 0xf4, 0x0e, 0xae, 0x47, 0x38,
 115 };
 116
 117 static const char md5salt_boot[MD5SUM_LEN] = {
 118         0x8c, 0xef, 0x33, 0x5b, 0xd5, 0xc5, 0xce, 0xfa,
 119         0xa7, 0x9c, 0x28, 0xda, 0xb2, 0xe9, 0x0f, 0x42,
 120 };
 121
 122 static struct flash_layout layouts[] = {
 123         {
 124                 .id             = "4M",
 125                 .fw_max_len     = 0x3c0000,
 126                 .kernel_la      = 0x80060000,
 127                 .kernel_ep      = 0x80060000,
 128                 .rootfs_ofs     = 0x140000,
 129         }, {
 130                 .id             = "4Mlzma",
 131                 .fw_max_len     = 0x3c0000,
 132                 .kernel_la      = 0x80060000,
 133                 .kernel_ep      = 0x80060000,
 134                 .rootfs_ofs     = 0x100000,
 135         }, {
 136                 .id             = "8M",
 137                 .fw_max_len     = 0x7c0000,
 138                 .kernel_la      = 0x80060000,
 139                 .kernel_ep      = 0x80060000,
 140                 .rootfs_ofs     = 0x140000,
 141         }, {
 142                 .id             = "8Mlzma",
 143                 .fw_max_len     = 0x7c0000,
 144                 .kernel_la      = 0x80060000,
 145                 .kernel_ep      = 0x80060000,
 146                 .rootfs_ofs     = 0x100000,
 147         }, {
 148                 .id             = "16M",
 149                 .fw_max_len     = 0xf80000,
 150                 .kernel_la      = 0x80060000,
 151                 .kernel_ep      = 0x80060000,
 152                 .rootfs_ofs     = 0x140000,
 153         }, {
 154                 .id             = "16Mlzma",
 155                 .fw_max_len     = 0xf80000,
 156                 .kernel_la      = 0x80060000,
 157                 .kernel_ep      = 0x80060000,
 158                 .rootfs_ofs     = 0x100000,
 159         }, {
 160                 .id             = "16Mppc",
 161                 .fw_max_len     = 0xf80000,
 162                 .kernel_la      = 0x00000000 ,
 163                 .kernel_ep      = 0xc0000000,
 164                 .rootfs_ofs     = 0x2a0000,
 165         }, {
 166                 /* terminating entry */
 167         }
 168 };
 169
 170 static const struct fw_region regions[] = {
 171         /* Default region (universal) uses code 0 as well */
 172         {"US", 1},
 173         {"EU", 0},
 174         {"BR", 0},
 175 };
 176
 177 static const struct fw_region * find_region(const char *country) {
 178         size_t i;
 179
 180         for (i = 0; i < ARRAY_SIZE(regions); i++) {
 181                 if (strcasecmp(regions[i].name, country) == 0)
 182                         return &regions[i];
 183         }
 184
 185         return NULL;
 186 }
 187
 188 static void usage(int status)
 189 {
 190         fprintf(stderr, "Usage: %s [OPTIONS...]\n", progname);
 191         fprintf(stderr,
 192 "\n"
 193 "Options:\n"
 194 "  -c              use combined kernel image\n"
 195 "  -e              swap endianness in kernel load address and entry point\n"
 196 "  -E <ep>         overwrite kernel entry point with <ep> (hexval prefixed with 0x)\n"
 197 "  -L <la>         overwrite kernel load address with <la> (hexval prefixed with 0x)\n"
 198 "  -H <hwid>       use hardware id specified with <hwid>\n"
 199 "  -W <hwrev>      use hardware revision specified with <hwrev>\n"
 200 "  -C <country>    set region code to <country>\n"
 201 "  -F <id>         use flash layout specified with <id>\n"
 202 "  -k <file>       read kernel image from the file <file>\n"
 203 "  -r <file>       read rootfs image from the file <file>\n"
 204 "  -a <align>      align the rootfs start on an <align> bytes boundary\n"
 205 "  -R <offset>     overwrite rootfs offset with <offset> (hexval prefixed with 0x)\n"
 206 "  -O              calculate rootfs offset for combined images\n"
 207 "  -o <file>       write output to the file <file>\n"
 208 "  -s              strip padding from the end of the image\n"
 209 "  -j              add jffs2 end-of-filesystem markers\n"
 210 "  -N <vendor>     set image vendor to <vendor>\n"
 211 "  -V <version>    set image version to <version>\n"
 212 "  -v <version>    set firmware version to <version>\n"
 213 "  -m <version>    set header version to <version>\n"
 214 "  -i <file>       inspect given firmware file <file>\n"
 215 "  -x              extract kernel and rootfs while inspecting (requires -i)\n"
 216 "  -X <size>       reserve <size> bytes in the firmware image (hexval prefixed with 0x)\n"
 217 "  -h              show this screen\n"
 218         );
 219
 220         exit(status);
 221 }
 222
 223 static int check_options(void)
 224 {
 225         int ret;
 226         int exceed_bytes;
 227
 228         if (inspect_info.file_name) {
 229                 ret = get_file_stat(&inspect_info);
 230                 if (ret)
 231                         return ret;
 232
 233                 return 0;
 234         } else if (extract) {
 235                 ERR("no firmware for inspection specified");
 236                 return -1;
 237         }
 238
 239         if (opt_hw_id == NULL) {
 240                 ERR("hardware id not specified");
 241                 return -1;
 242         }
 243         hw_id = strtoul(opt_hw_id, NULL, 0);
 244
 245         if (!combined && layout_id == NULL) {
 246                 ERR("flash layout is not specified");
 247                 return -1;
 248         }
 249
 250         if (opt_hw_rev)
 251                 hw_rev = strtoul(opt_hw_rev, NULL, 0);
 252         else
 253                 hw_rev = 1;
 254
 255         if (country) {
 256                 region = find_region(country);
 257                 if (!region) {
 258                         ERR("unknown region code \"%s\"", country);
 259                         return -1;
 260                 }
 261         }
 262
 263         if (combined) {
 264                 if (!kernel_la || !kernel_ep) {
 265                         ERR("kernel loading address and entry point must be specified for combined image");
 266                         return -1;
 267                 }
 268         } else {
 269                 layout = find_layout(layouts, layout_id);
 270                 if (layout == NULL) {
 271                         ERR("unknown flash layout \"%s\"", layout_id);
 272                         return -1;
 273                 }
 274
 275                 if (!kernel_la)
 276                         kernel_la = layout->kernel_la;
 277                 if (!kernel_ep)
 278                         kernel_ep = layout->kernel_ep;
 279                 if (!rootfs_ofs)
 280                         rootfs_ofs = layout->rootfs_ofs;
 281
 282                 if (reserved_space > layout->fw_max_len) {
 283                         ERR("reserved space is not valid");
 284                         return -1;
 285                 }
 286         }
 287
 288         if (kernel_info.file_name == NULL) {
 289                 ERR("no kernel image specified");
 290                 return -1;
 291         }
 292
 293         ret = get_file_stat(&kernel_info);
 294         if (ret)
 295                 return ret;
 296
 297         kernel_len = kernel_info.file_size;
 298
 299         if (!combined) {
 300                 fw_max_len = layout->fw_max_len - reserved_space;
 301
 302                 if (rootfs_info.file_name == NULL) {
 303                         ERR("no rootfs image specified");
 304                         return -1;
 305                 }
 306
 307                 ret = get_file_stat(&rootfs_info);
 308                 if (ret)
 309                         return ret;
 310
 311                 if (rootfs_align) {
 312                         kernel_len += sizeof(struct fw_header);
 313                         rootfs_ofs = ALIGN(kernel_len, rootfs_align);
 314                         kernel_len -= sizeof(struct fw_header);
 315
 316                         DBG("rootfs offset aligned to 0x%u", rootfs_ofs);
 317
 318                         exceed_bytes = kernel_len + rootfs_info.file_size - (fw_max_len - sizeof(struct fw_header));
 319                         if (exceed_bytes > 0) {
 320                                 ERR("images are too big by %i bytes", exceed_bytes);
 321                                 return -1;
 322                         }
 323                 } else {
 324                         exceed_bytes = kernel_info.file_size - (rootfs_ofs - sizeof(struct fw_header));
 325                         if (exceed_bytes > 0) {
 326                                 ERR("kernel image is too big by %i bytes", exceed_bytes);
 327                                 return -1;
 328                         }
 329
 330                         exceed_bytes = rootfs_info.file_size - (fw_max_len - rootfs_ofs);
 331                         if (exceed_bytes > 0) {
 332                                 ERR("rootfs image is too big by %i bytes", exceed_bytes);
 333                                 return -1;
 334                         }
 335                 }
 336         }
 337
 338         if (ofname == NULL) {
 339                 ERR("no output file specified");
 340                 return -1;
 341         }
 342
 343         ret = sscanf(fw_ver, "%d.%d.%d", &fw_ver_hi, &fw_ver_mid, &fw_ver_lo);
 344         if (ret != 3) {
 345                 ERR("invalid firmware version '%s'", fw_ver);
 346                 return -1;
 347         }
 348
 349         if (opt_hdr_ver == 1) {
 350                 hdr_ver = HEADER_VERSION_V1;
 351         } else if (opt_hdr_ver == 2) {
 352                 hdr_ver = HEADER_VERSION_V2;
 353         } else {
 354                 ERR("invalid header version '%u'", opt_hdr_ver);
 355                 return -1;
 356         }
 357
 358         return 0;
 359 }
 360
 361 void fill_header(char *buf, int len)
 362 {
 363         struct fw_header *hdr = (struct fw_header *)buf;
 364
 365         memset(hdr, 0, sizeof(struct fw_header));
 366
 367         hdr->version = htonl(hdr_ver);
 368         strncpy(hdr->vendor_name, vendor, sizeof(hdr->vendor_name));
 369         strncpy(hdr->fw_version, version, sizeof(hdr->fw_version));
 370         hdr->hw_id = htonl(hw_id);
 371         hdr->hw_rev = htonl(hw_rev);
 372
 373         hdr->kernel_la = htonl(kernel_la);
 374         hdr->kernel_ep = htonl(kernel_ep);
 375         hdr->kernel_ofs = htonl(sizeof(struct fw_header));
 376         hdr->kernel_len = htonl(kernel_len);
 377
 378         if (!combined) {
 379                 if (boot_info.file_size == 0)
 380                         memcpy(hdr->md5sum1, md5salt_normal, sizeof(hdr->md5sum1));
 381                 else
 382                         memcpy(hdr->md5sum1, md5salt_boot, sizeof(hdr->md5sum1));
 383
 384                 hdr->fw_length = htonl(layout->fw_max_len);
 385                 hdr->rootfs_ofs = htonl(rootfs_ofs);
 386                 hdr->rootfs_len = htonl(rootfs_info.file_size);
 387         }
 388
 389         if (combined && rootfs_ofs_calc) {
 390                 hdr->rootfs_ofs = htonl(sizeof(struct fw_header) + kernel_len);
 391         }
 392
 393         hdr->ver_hi = htons(fw_ver_hi);
 394         hdr->ver_mid = htons(fw_ver_mid);
 395         hdr->ver_lo = htons(fw_ver_lo);
 396
 397         if (region) {
 398                 hdr->region_code = htonl(region->code);
 399                 snprintf(
 400                         hdr->region_str1, sizeof(hdr->region_str1), "00000000;%02X%02X%02X%02X;",
 401                         region->name[0], region->name[1], region->name[2], region->name[3]
 402                 );
 403                 snprintf(
 404                         hdr->region_str2, sizeof(hdr->region_str2), "%02X%02X%02X%02X",
 405                         region->name[0], region->name[1], region->name[2], region->name[3]
 406                 );
 407         }
 408
 409         if (endian_swap) {
 410                 hdr->kernel_la = bswap_32(hdr->kernel_la);
 411                 hdr->kernel_ep = bswap_32(hdr->kernel_ep);
 412         }
 413
 414         if (!combined)
 415                 get_md5(buf, len, hdr->md5sum1);
 416 }
 417
 418 static int inspect_fw(void)
 419 {
 420         char *buf;
 421         struct fw_header *hdr;
 422         uint8_t md5sum[MD5SUM_LEN];
 423         int ret = EXIT_FAILURE;
 424
 425         buf = malloc(inspect_info.file_size);
 426         if (!buf) {
 427                 ERR("no memory for buffer!\n");
 428                 goto out;
 429         }
 430
 431         ret = read_to_buf(&inspect_info, buf);
 432         if (ret)
 433                 goto out_free_buf;
 434         hdr = (struct fw_header *)buf;
 435
 436         inspect_fw_pstr("File name", inspect_info.file_name);
 437         inspect_fw_phexdec("File size", inspect_info.file_size);
 438
 439         if ((ntohl(hdr->version) != HEADER_VERSION_V1) &&
 440             (ntohl(hdr->version) != HEADER_VERSION_V2)) {
 441                 ERR("file does not seem to have V1/V2 header!\n");
 442                 goto out_free_buf;
 443         }
 444
 445         inspect_fw_phexdec("Version 1 Header size", sizeof(struct fw_header));
 446
 447         memcpy(md5sum, hdr->md5sum1, sizeof(md5sum));
 448         if (ntohl(hdr->boot_len) == 0)
 449                 memcpy(hdr->md5sum1, md5salt_normal, sizeof(md5sum));
 450         else
 451                 memcpy(hdr->md5sum1, md5salt_boot, sizeof(md5sum));
 452         get_md5(buf, inspect_info.file_size, hdr->md5sum1);
 453
 454         if (memcmp(md5sum, hdr->md5sum1, sizeof(md5sum))) {
 455                 inspect_fw_pmd5sum("Header MD5Sum1", md5sum, "(*ERROR*)");
 456                 inspect_fw_pmd5sum("          --> expected", hdr->md5sum1, "");
 457         } else {
 458                 inspect_fw_pmd5sum("Header MD5Sum1", md5sum, "(ok)");
 459         }
 460         if (ntohl(hdr->unk2) != 0)
 461                 inspect_fw_phexdec("Unknown value 2", hdr->unk2);
 462         inspect_fw_pmd5sum("Header MD5Sum2", hdr->md5sum2,
 463                            "(purpose yet unknown, unchecked here)");
 464         if (ntohl(hdr->unk3) != 0)
 465                 inspect_fw_phexdec("Unknown value 3", hdr->unk3);
 466
 467         printf("\n");
 468
 469         inspect_fw_pstr("Vendor name", hdr->vendor_name);
 470         inspect_fw_pstr("Firmware version", hdr->fw_version);
 471         inspect_fw_phex("Hardware ID", ntohl(hdr->hw_id));
 472         inspect_fw_phex("Hardware Revision", ntohl(hdr->hw_rev));
 473         inspect_fw_phex("Region code", ntohl(hdr->region_code));
 474
 475         printf("\n");
 476
 477         inspect_fw_phexdec("Kernel data offset",
 478                            ntohl(hdr->kernel_ofs));
 479         inspect_fw_phexdec("Kernel data length",
 480                            ntohl(hdr->kernel_len));
 481         inspect_fw_phex("Kernel load address",
 482                         ntohl(hdr->kernel_la));
 483         inspect_fw_phex("Kernel entry point",
 484                         ntohl(hdr->kernel_ep));
 485         inspect_fw_phexdec("Rootfs data offset",
 486                            ntohl(hdr->rootfs_ofs));
 487         inspect_fw_phexdec("Rootfs data length",
 488                            ntohl(hdr->rootfs_len));
 489         inspect_fw_phexdec("Boot loader data offset",
 490                            ntohl(hdr->boot_ofs));
 491         inspect_fw_phexdec("Boot loader data length",
 492                            ntohl(hdr->boot_len));
 493         inspect_fw_phexdec("Total firmware length",
 494                            ntohl(hdr->fw_length));
 495
 496         if (extract) {
 497                 FILE *fp;
 498                 char *filename;
 499
 500                 printf("\n");
 501
 502                 filename = malloc(strlen(inspect_info.file_name) + 8);
 503                 sprintf(filename, "%s-kernel", inspect_info.file_name);
 504                 printf("Extracting kernel to \"%s\"...\n", filename);
 505                 fp = fopen(filename, "w");
 506                 if (fp) {
 507                         if (!fwrite(buf + ntohl(hdr->kernel_ofs),
 508                                     ntohl(hdr->kernel_len), 1, fp)) {
 509                                 ERR("error in fwrite(): %s", strerror(errno));
 510                         }
 511                         fclose(fp);
 512                 } else {
 513                         ERR("error in fopen(): %s", strerror(errno));
 514                 }
 515                 free(filename);
 516
 517                 filename = malloc(strlen(inspect_info.file_name) + 8);
 518                 sprintf(filename, "%s-rootfs", inspect_info.file_name);
 519                 printf("Extracting rootfs to \"%s\"...\n", filename);
 520                 fp = fopen(filename, "w");
 521                 if (fp) {
 522                         if (!fwrite(buf + ntohl(hdr->rootfs_ofs),
 523                                     ntohl(hdr->rootfs_len), 1, fp)) {
 524                                 ERR("error in fwrite(): %s", strerror(errno));
 525                         }
 526                         fclose(fp);
 527                 } else {
 528                         ERR("error in fopen(): %s", strerror(errno));
 529                 }
 530                 free(filename);
 531         }
 532
 533  out_free_buf:
 534         free(buf);
 535  out:
 536         return ret;
 537 }
 538
 539 int main(int argc, char *argv[])
 540 {
 541         int ret = EXIT_FAILURE;
 542
 543         progname = basename(argv[0]);
 544
 545         while ( 1 ) {
 546                 int c;
 547
 548                 c = getopt(argc, argv, "a:H:E:F:L:m:V:N:W:C:ci:k:r:R:o:OxX:ehsjv:");
 549                 if (c == -1)
 550                         break;
 551
 552                 switch (c) {
 553                 case 'a':
 554                         sscanf(optarg, "0x%x", &rootfs_align);
 555                         break;
 556                 case 'H':
 557                         opt_hw_id = optarg;
 558                         break;
 559                 case 'E':
 560                         sscanf(optarg, "0x%x", &kernel_ep);
 561                         break;
 562                 case 'F':
 563                         layout_id = optarg;
 564                         break;
 565                 case 'W':
 566                         opt_hw_rev = optarg;
 567                         break;
 568                 case 'C':
 569                         country = optarg;
 570                         break;
 571                 case 'L':
 572                         sscanf(optarg, "0x%x", &kernel_la);
 573                         break;
 574                 case 'm':
 575                         sscanf(optarg, "%u", &opt_hdr_ver);
 576                         break;
 577                 case 'V':
 578                         version = optarg;
 579                         break;
 580                 case 'v':
 581                         fw_ver = optarg;
 582                         break;
 583                 case 'N':
 584                         vendor = optarg;
 585                         break;
 586                 case 'c':
 587                         combined++;
 588                         break;
 589                 case 'k':
 590                         kernel_info.file_name = optarg;
 591                         break;
 592                 case 'r':
 593                         rootfs_info.file_name = optarg;
 594                         break;
 595                 case 'R':
 596                         sscanf(optarg, "0x%x", &rootfs_ofs);
 597                         break;
 598                 case 'o':
 599                         ofname = optarg;
 600                         break;
 601                 case 'O':
 602                         rootfs_ofs_calc = 1;
 603                         break;
 604                 case 's':
 605                         strip_padding = 1;
 606                         break;
 607                 case 'i':
 608                         inspect_info.file_name = optarg;
 609                         break;
 610                 case 'j':
 611                         add_jffs2_eof = 1;
 612                         break;
 613                 case 'x':
 614                         extract = 1;
 615                         break;
 616                 case 'e':
 617                         endian_swap = true;
 618                         break;
 619                 case 'h':
 620                         usage(EXIT_SUCCESS);
 621                         break;
 622                 case 'X':
 623                         sscanf(optarg, "0x%x", &reserved_space);
 624                         break;
 625                 default:
 626                         usage(EXIT_FAILURE);
 627                         break;
 628                 }
 629         }
 630
 631         ret = check_options();
 632         if (ret)
 633                 goto out;
 634
 635         if (!inspect_info.file_name)
 636                 ret = build_fw(sizeof(struct fw_header));
 637         else
 638                 ret = inspect_fw();
 639
 640  out:
 641         return ret;
 642 }