src/mktplinkfw.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   4  *
   5  * This tool was based on:
   6  *   TP-Link WR941 V2 firmware checksum fixing tool.
   7  *   Copyright (C) 2008,2009 Wang Jian <lark@linux.net.cn>
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <stdint.h>
  13 #include <string.h>
  14 #include <byteswap.h>
  15 #include <unistd.h>     /* for unlink() */
  16 #include <libgen.h>
  17 #include <getopt.h>     /* for getopt() */
  18 #include <stdarg.h>
  19 #include <stdbool.h>
  20 #include <endian.h>
  21 #include <errno.h>
  22 #include <sys/stat.h>
  23
  24 #include <arpa/inet.h>
  25 #include <netinet/in.h>
  26
  27 #include "md5.h"
  28 #include "mktplinkfw-lib.h"
  29
  30 #define HEADER_VERSION_V1       0x01000000
  31 #define HEADER_VERSION_V2       0x02000000
  32
  33 struct fw_header {
  34         uint32_t        version;        /* header version */
  35         char            vendor_name[24];
  36         char            fw_version[36];
  37         uint32_t        hw_id;          /* hardware id */
  38         uint32_t        hw_rev;         /* hardware revision */
  39         uint32_t        region_code;    /* region code */
  40         uint8_t         md5sum1[MD5SUM_LEN];
  41         uint32_t        unk2;
  42         uint8_t         md5sum2[MD5SUM_LEN];
  43         uint32_t        unk3;
  44         uint32_t        kernel_la;      /* kernel load address */
  45         uint32_t        kernel_ep;      /* kernel entry point */
  46         uint32_t        fw_length;      /* total length of the firmware */
  47         uint32_t        kernel_ofs;     /* kernel data offset */
  48         uint32_t        kernel_len;     /* kernel data length */
  49         uint32_t        rootfs_ofs;     /* rootfs data offset */
  50         uint32_t        rootfs_len;     /* rootfs data length */
  51         uint32_t        boot_ofs;       /* bootloader data offset */
  52         uint32_t        boot_len;       /* bootloader data length */
  53         uint16_t        ver_hi;
  54         uint16_t        ver_mid;
  55         uint16_t        ver_lo;
  56         uint8_t         pad[130];
  57         char            region_str1[32];
  58         char            region_str2[32];
  59         uint8_t         pad2[160];
  60 } __attribute__ ((packed));
  61
  62 struct fw_region {
  63         char            name[4];
  64         uint32_t        code;
  65 };
  66
  67
  68 /*
  69  * Globals
  70  */
  71 char *ofname;
  72 char *progname;
  73 static char *vendor = "TP-LINK Technologies";
  74 static char *version = "ver. 1.0";
  75 static char *fw_ver = "0.0.0";
  76 static uint32_t hdr_ver = HEADER_VERSION_V1;
  77
  78 static char *layout_id;
  79 struct flash_layout *layout;
  80 static char *opt_hw_id;
  81 static uint32_t hw_id;
  82 static char *opt_hw_rev;
  83 static uint32_t hw_rev;
  84 static uint32_t opt_hdr_ver = 1;
  85 static char *country;
  86 static const struct fw_region *region;
  87 static int fw_ver_lo;
  88 static int fw_ver_mid;
  89 static int fw_ver_hi;
  90 struct file_info kernel_info;
  91 static uint32_t kernel_la = 0;
  92 static uint32_t kernel_ep = 0;
  93 uint32_t kernel_len = 0;
  94 struct file_info rootfs_info;
  95 uint32_t rootfs_ofs = 0;
  96 uint32_t rootfs_align;
  97 static struct file_info boot_info;
  98 int combined;
  99 int strip_padding;
 100 int add_jffs2_eof;
 101 static uint32_t fw_max_len;
 102 static uint32_t reserved_space;
 103
 104 static struct file_info inspect_info;
 105 static int extract = 0;
 106 static bool endian_swap = false;
 107 static bool rootfs_ofs_calc = false;
 108
 109 static const char md5salt_normal[MD5SUM_LEN] = {
 110         0xdc, 0xd7, 0x3a, 0xa5, 0xc3, 0x95, 0x98, 0xfb,
 111         0xdd, 0xf9, 0xe7, 0xf4, 0x0e, 0xae, 0x47, 0x38,
 112 };
 113
 114 static const char md5salt_boot[MD5SUM_LEN] = {
 115         0x8c, 0xef, 0x33, 0x5b, 0xd5, 0xc5, 0xce, 0xfa,
 116         0xa7, 0x9c, 0x28, 0xda, 0xb2, 0xe9, 0x0f, 0x42,
 117 };
 118
 119 static struct flash_layout layouts[] = {
 120         {
 121                 .id             = "4M",
 122                 .fw_max_len     = 0x3c0000,
 123                 .kernel_la      = 0x80060000,
 124                 .kernel_ep      = 0x80060000,
 125                 .rootfs_ofs     = 0x140000,
 126         }, {
 127                 .id             = "4Mlzma",
 128                 .fw_max_len     = 0x3c0000,
 129                 .kernel_la      = 0x80060000,
 130                 .kernel_ep      = 0x80060000,
 131                 .rootfs_ofs     = 0x100000,
 132         }, {
 133                 .id             = "8M",
 134                 .fw_max_len     = 0x7c0000,
 135                 .kernel_la      = 0x80060000,
 136                 .kernel_ep      = 0x80060000,
 137                 .rootfs_ofs     = 0x140000,
 138         }, {
 139                 .id             = "8Mlzma",
 140                 .fw_max_len     = 0x7c0000,
 141                 .kernel_la      = 0x80060000,
 142                 .kernel_ep      = 0x80060000,
 143                 .rootfs_ofs     = 0x100000,
 144         }, {
 145                 .id             = "8Mmtk",
 146                 .fw_max_len     = 0x7c0000,
 147                 .kernel_la      = 0x80000000,
 148                 .kernel_ep      = 0x8000c310,
 149                 .rootfs_ofs     = 0x100000,
 150         }, {
 151                 .id             = "16M",
 152                 .fw_max_len     = 0xf80000,
 153                 .kernel_la      = 0x80060000,
 154                 .kernel_ep      = 0x80060000,
 155                 .rootfs_ofs     = 0x140000,
 156         }, {
 157                 .id             = "16Mlzma",
 158                 .fw_max_len     = 0xf80000,
 159                 .kernel_la      = 0x80060000,
 160                 .kernel_ep      = 0x80060000,
 161                 .rootfs_ofs     = 0x100000,
 162         }, {
 163                 .id             = "16Mppc",
 164                 .fw_max_len     = 0xf80000,
 165                 .kernel_la      = 0x00000000 ,
 166                 .kernel_ep      = 0xc0000000,
 167                 .rootfs_ofs     = 0x2a0000,
 168         }, {
 169                 /* terminating entry */
 170         }
 171 };
 172
 173 static const struct fw_region regions[] = {
 174         /* Default region (universal) uses code 0 as well */
 175         {"US", 1},
 176         {"EU", 0},
 177         {"BR", 0},
 178 };
 179
 180 static const struct fw_region * find_region(const char *country) {
 181         size_t i;
 182
 183         for (i = 0; i < ARRAY_SIZE(regions); i++) {
 184                 if (strcasecmp(regions[i].name, country) == 0)
 185                         return &regions[i];
 186         }
 187
 188         return NULL;
 189 }
 190
 191 static void usage(int status)
 192 {
 193         fprintf(stderr, "Usage: %s [OPTIONS...]\n", progname);
 194         fprintf(stderr,
 195 "\n"
 196 "Options:\n"
 197 "  -c              use combined kernel image\n"
 198 "  -e              swap endianness in kernel load address and entry point\n"
 199 "  -E <ep>         overwrite kernel entry point with <ep> (hexval prefixed with 0x)\n"
 200 "  -L <la>         overwrite kernel load address with <la> (hexval prefixed with 0x)\n"
 201 "  -H <hwid>       use hardware id specified with <hwid>\n"
 202 "  -W <hwrev>      use hardware revision specified with <hwrev>\n"
 203 "  -C <country>    set region code to <country>\n"
 204 "  -F <id>         use flash layout specified with <id>\n"
 205 "  -k <file>       read kernel image from the file <file>\n"
 206 "  -r <file>       read rootfs image from the file <file>\n"
 207 "  -a <align>      align the rootfs start on an <align> bytes boundary\n"
 208 "  -R <offset>     overwrite rootfs offset with <offset> (hexval prefixed with 0x)\n"
 209 "  -O              calculate rootfs offset for combined images\n"
 210 "  -o <file>       write output to the file <file>\n"
 211 "  -s              strip padding from the end of the image\n"
 212 "  -j              add jffs2 end-of-filesystem markers\n"
 213 "  -N <vendor>     set image vendor to <vendor>\n"
 214 "  -V <version>    set image version to <version>\n"
 215 "  -v <version>    set firmware version to <version>\n"
 216 "  -m <version>    set header version to <version>\n"
 217 "  -i <file>       inspect given firmware file <file>\n"
 218 "  -x              extract kernel and rootfs while inspecting (requires -i)\n"
 219 "  -X <size>       reserve <size> bytes in the firmware image (hexval prefixed with 0x)\n"
 220 "  -h              show this screen\n"
 221         );
 222
 223         exit(status);
 224 }
 225
 226 static int check_options(void)
 227 {
 228         int ret;
 229         int exceed_bytes;
 230
 231         if (inspect_info.file_name) {
 232                 ret = get_file_stat(&inspect_info);
 233                 if (ret)
 234                         return ret;
 235
 236                 return 0;
 237         } else if (extract) {
 238                 ERR("no firmware for inspection specified");
 239                 return -1;
 240         }
 241
 242         if (opt_hw_id == NULL) {
 243                 ERR("hardware id not specified");
 244                 return -1;
 245         }
 246         hw_id = strtoul(opt_hw_id, NULL, 0);
 247
 248         if (!combined && layout_id == NULL) {
 249                 ERR("flash layout is not specified");
 250                 return -1;
 251         }
 252
 253         if (opt_hw_rev)
 254                 hw_rev = strtoul(opt_hw_rev, NULL, 0);
 255         else
 256                 hw_rev = 1;
 257
 258         if (country) {
 259                 region = find_region(country);
 260                 if (!region) {
 261                         ERR("unknown region code \"%s\"", country);
 262                         return -1;
 263                 }
 264         }
 265
 266         if (combined) {
 267                 if (!kernel_la || !kernel_ep) {
 268                         ERR("kernel loading address and entry point must be specified for combined image");
 269                         return -1;
 270                 }
 271         } else {
 272                 layout = find_layout(layouts, layout_id);
 273                 if (layout == NULL) {
 274                         ERR("unknown flash layout \"%s\"", layout_id);
 275                         return -1;
 276                 }
 277
 278                 if (!kernel_la)
 279                         kernel_la = layout->kernel_la;
 280                 if (!kernel_ep)
 281                         kernel_ep = layout->kernel_ep;
 282                 if (!rootfs_ofs)
 283                         rootfs_ofs = layout->rootfs_ofs;
 284
 285                 if (reserved_space > layout->fw_max_len) {
 286                         ERR("reserved space is not valid");
 287                         return -1;
 288                 }
 289         }
 290
 291         if (kernel_info.file_name == NULL) {
 292                 ERR("no kernel image specified");
 293                 return -1;
 294         }
 295
 296         ret = get_file_stat(&kernel_info);
 297         if (ret)
 298                 return ret;
 299
 300         kernel_len = kernel_info.file_size;
 301
 302         if (!combined) {
 303                 fw_max_len = layout->fw_max_len - reserved_space;
 304
 305                 if (rootfs_info.file_name == NULL) {
 306                         ERR("no rootfs image specified");
 307                         return -1;
 308                 }
 309
 310                 ret = get_file_stat(&rootfs_info);
 311                 if (ret)
 312                         return ret;
 313
 314                 if (rootfs_align) {
 315                         kernel_len += sizeof(struct fw_header);
 316                         rootfs_ofs = ALIGN(kernel_len, rootfs_align);
 317                         kernel_len -= sizeof(struct fw_header);
 318
 319                         DBG("rootfs offset aligned to 0x%u", rootfs_ofs);
 320
 321                         exceed_bytes = kernel_len + rootfs_info.file_size - (fw_max_len - sizeof(struct fw_header));
 322                         if (exceed_bytes > 0) {
 323                                 ERR("images are too big by %i bytes", exceed_bytes);
 324                                 return -1;
 325                         }
 326                 } else {
 327                         exceed_bytes = kernel_info.file_size - (rootfs_ofs - sizeof(struct fw_header));
 328                         if (exceed_bytes > 0) {
 329                                 ERR("kernel image is too big by %i bytes", exceed_bytes);
 330                                 return -1;
 331                         }
 332
 333                         exceed_bytes = rootfs_info.file_size - (fw_max_len - rootfs_ofs);
 334                         if (exceed_bytes > 0) {
 335                                 ERR("rootfs image is too big by %i bytes", exceed_bytes);
 336                                 return -1;
 337                         }
 338                 }
 339         }
 340
 341         if (ofname == NULL) {
 342                 ERR("no output file specified");
 343                 return -1;
 344         }
 345
 346         ret = sscanf(fw_ver, "%d.%d.%d", &fw_ver_hi, &fw_ver_mid, &fw_ver_lo);
 347         if (ret != 3) {
 348                 ERR("invalid firmware version '%s'", fw_ver);
 349                 return -1;
 350         }
 351
 352         if (opt_hdr_ver == 1) {
 353                 hdr_ver = HEADER_VERSION_V1;
 354         } else if (opt_hdr_ver == 2) {
 355                 hdr_ver = HEADER_VERSION_V2;
 356         } else {
 357                 ERR("invalid header version '%u'", opt_hdr_ver);
 358                 return -1;
 359         }
 360
 361         return 0;
 362 }
 363
 364 void fill_header(char *buf, int len)
 365 {
 366         struct fw_header *hdr = (struct fw_header *)buf;
 367
 368         memset(hdr, 0, sizeof(struct fw_header));
 369
 370         hdr->version = htonl(hdr_ver);
 371         strncpy(hdr->vendor_name, vendor, sizeof(hdr->vendor_name));
 372         strncpy(hdr->fw_version, version, sizeof(hdr->fw_version));
 373         hdr->hw_id = htonl(hw_id);
 374         hdr->hw_rev = htonl(hw_rev);
 375
 376         hdr->kernel_la = htonl(kernel_la);
 377         hdr->kernel_ep = htonl(kernel_ep);
 378         hdr->kernel_ofs = htonl(sizeof(struct fw_header));
 379         hdr->kernel_len = htonl(kernel_len);
 380
 381         if (!combined) {
 382                 if (boot_info.file_size == 0)
 383                         memcpy(hdr->md5sum1, md5salt_normal, sizeof(hdr->md5sum1));
 384                 else
 385                         memcpy(hdr->md5sum1, md5salt_boot, sizeof(hdr->md5sum1));
 386
 387                 hdr->fw_length = htonl(layout->fw_max_len);
 388                 hdr->rootfs_ofs = htonl(rootfs_ofs);
 389                 hdr->rootfs_len = htonl(rootfs_info.file_size);
 390         }
 391
 392         if (combined && rootfs_ofs_calc) {
 393                 hdr->rootfs_ofs = htonl(sizeof(struct fw_header) + kernel_len);
 394         }
 395
 396         hdr->ver_hi = htons(fw_ver_hi);
 397         hdr->ver_mid = htons(fw_ver_mid);
 398         hdr->ver_lo = htons(fw_ver_lo);
 399
 400         if (region) {
 401                 hdr->region_code = htonl(region->code);
 402                 snprintf(
 403                         hdr->region_str1, sizeof(hdr->region_str1), "00000000;%02X%02X%02X%02X;",
 404                         region->name[0], region->name[1], region->name[2], region->name[3]
 405                 );
 406                 snprintf(
 407                         hdr->region_str2, sizeof(hdr->region_str2), "%02X%02X%02X%02X",
 408                         region->name[0], region->name[1], region->name[2], region->name[3]
 409                 );
 410         }
 411
 412         if (endian_swap) {
 413                 hdr->kernel_la = bswap_32(hdr->kernel_la);
 414                 hdr->kernel_ep = bswap_32(hdr->kernel_ep);
 415         }
 416
 417         if (!combined)
 418                 get_md5(buf, len, hdr->md5sum1);
 419 }
 420
 421 static int inspect_fw(void)
 422 {
 423         char *buf;
 424         struct fw_header *hdr;
 425         uint8_t md5sum[MD5SUM_LEN];
 426         int ret = EXIT_FAILURE;
 427
 428         buf = malloc(inspect_info.file_size);
 429         if (!buf) {
 430                 ERR("no memory for buffer!\n");
 431                 goto out;
 432         }
 433
 434         ret = read_to_buf(&inspect_info, buf);
 435         if (ret)
 436                 goto out_free_buf;
 437         hdr = (struct fw_header *)buf;
 438
 439         inspect_fw_pstr("File name", inspect_info.file_name);
 440         inspect_fw_phexdec("File size", inspect_info.file_size);
 441
 442         if ((ntohl(hdr->version) != HEADER_VERSION_V1) &&
 443             (ntohl(hdr->version) != HEADER_VERSION_V2)) {
 444                 ERR("file does not seem to have V1/V2 header!\n");
 445                 goto out_free_buf;
 446         }
 447
 448         inspect_fw_phexdec("Version 1 Header size", sizeof(struct fw_header));
 449
 450         memcpy(md5sum, hdr->md5sum1, sizeof(md5sum));
 451         if (ntohl(hdr->boot_len) == 0)
 452                 memcpy(hdr->md5sum1, md5salt_normal, sizeof(md5sum));
 453         else
 454                 memcpy(hdr->md5sum1, md5salt_boot, sizeof(md5sum));
 455         get_md5(buf, inspect_info.file_size, hdr->md5sum1);
 456
 457         if (memcmp(md5sum, hdr->md5sum1, sizeof(md5sum))) {
 458                 inspect_fw_pmd5sum("Header MD5Sum1", md5sum, "(*ERROR*)");
 459                 inspect_fw_pmd5sum("          --> expected", hdr->md5sum1, "");
 460         } else {
 461                 inspect_fw_pmd5sum("Header MD5Sum1", md5sum, "(ok)");
 462         }
 463         if (ntohl(hdr->unk2) != 0)
 464                 inspect_fw_phexdec("Unknown value 2", hdr->unk2);
 465         inspect_fw_pmd5sum("Header MD5Sum2", hdr->md5sum2,
 466                            "(purpose yet unknown, unchecked here)");
 467         if (ntohl(hdr->unk3) != 0)
 468                 inspect_fw_phexdec("Unknown value 3", hdr->unk3);
 469
 470         printf("\n");
 471
 472         inspect_fw_pstr("Vendor name", hdr->vendor_name);
 473         inspect_fw_pstr("Firmware version", hdr->fw_version);
 474         inspect_fw_phex("Hardware ID", ntohl(hdr->hw_id));
 475         inspect_fw_phex("Hardware Revision", ntohl(hdr->hw_rev));
 476         inspect_fw_phex("Region code", ntohl(hdr->region_code));
 477
 478         printf("\n");
 479
 480         inspect_fw_phexdec("Kernel data offset",
 481                            ntohl(hdr->kernel_ofs));
 482         inspect_fw_phexdec("Kernel data length",
 483                            ntohl(hdr->kernel_len));
 484         inspect_fw_phex("Kernel load address",
 485                         ntohl(hdr->kernel_la));
 486         inspect_fw_phex("Kernel entry point",
 487                         ntohl(hdr->kernel_ep));
 488         inspect_fw_phexdec("Rootfs data offset",
 489                            ntohl(hdr->rootfs_ofs));
 490         inspect_fw_phexdec("Rootfs data length",
 491                            ntohl(hdr->rootfs_len));
 492         inspect_fw_phexdec("Boot loader data offset",
 493                            ntohl(hdr->boot_ofs));
 494         inspect_fw_phexdec("Boot loader data length",
 495                            ntohl(hdr->boot_len));
 496         inspect_fw_phexdec("Total firmware length",
 497                            ntohl(hdr->fw_length));
 498
 499         if (extract) {
 500                 FILE *fp;
 501                 char *filename;
 502
 503                 printf("\n");
 504
 505                 filename = malloc(strlen(inspect_info.file_name) + 8);
 506                 sprintf(filename, "%s-kernel", inspect_info.file_name);
 507                 printf("Extracting kernel to \"%s\"...\n", filename);
 508                 fp = fopen(filename, "w");
 509                 if (fp) {
 510                         if (!fwrite(buf + ntohl(hdr->kernel_ofs),
 511                                     ntohl(hdr->kernel_len), 1, fp)) {
 512                                 ERR("error in fwrite(): %s", strerror(errno));
 513                         }
 514                         fclose(fp);
 515                 } else {
 516                         ERR("error in fopen(): %s", strerror(errno));
 517                 }
 518                 free(filename);
 519
 520                 filename = malloc(strlen(inspect_info.file_name) + 8);
 521                 sprintf(filename, "%s-rootfs", inspect_info.file_name);
 522                 printf("Extracting rootfs to \"%s\"...\n", filename);
 523                 fp = fopen(filename, "w");
 524                 if (fp) {
 525                         if (!fwrite(buf + ntohl(hdr->rootfs_ofs),
 526                                     ntohl(hdr->rootfs_len), 1, fp)) {
 527                                 ERR("error in fwrite(): %s", strerror(errno));
 528                         }
 529                         fclose(fp);
 530                 } else {
 531                         ERR("error in fopen(): %s", strerror(errno));
 532                 }
 533                 free(filename);
 534         }
 535
 536  out_free_buf:
 537         free(buf);
 538  out:
 539         return ret;
 540 }
 541
 542 int main(int argc, char *argv[])
 543 {
 544         int ret = EXIT_FAILURE;
 545
 546         progname = basename(argv[0]);
 547
 548         while ( 1 ) {
 549                 int c;
 550
 551                 c = getopt(argc, argv, "a:H:E:F:L:m:V:N:W:C:ci:k:r:R:o:OxX:ehsjv:");
 552                 if (c == -1)
 553                         break;
 554
 555                 switch (c) {
 556                 case 'a':
 557                         sscanf(optarg, "0x%x", &rootfs_align);
 558                         break;
 559                 case 'H':
 560                         opt_hw_id = optarg;
 561                         break;
 562                 case 'E':
 563                         sscanf(optarg, "0x%x", &kernel_ep);
 564                         break;
 565                 case 'F':
 566                         layout_id = optarg;
 567                         break;
 568                 case 'W':
 569                         opt_hw_rev = optarg;
 570                         break;
 571                 case 'C':
 572                         country = optarg;
 573                         break;
 574                 case 'L':
 575                         sscanf(optarg, "0x%x", &kernel_la);
 576                         break;
 577                 case 'm':
 578                         sscanf(optarg, "%u", &opt_hdr_ver);
 579                         break;
 580                 case 'V':
 581                         version = optarg;
 582                         break;
 583                 case 'v':
 584                         fw_ver = optarg;
 585                         break;
 586                 case 'N':
 587                         vendor = optarg;
 588                         break;
 589                 case 'c':
 590                         combined++;
 591                         break;
 592                 case 'k':
 593                         kernel_info.file_name = optarg;
 594                         break;
 595                 case 'r':
 596                         rootfs_info.file_name = optarg;
 597                         break;
 598                 case 'R':
 599                         sscanf(optarg, "0x%x", &rootfs_ofs);
 600                         break;
 601                 case 'o':
 602                         ofname = optarg;
 603                         break;
 604                 case 'O':
 605                         rootfs_ofs_calc = 1;
 606                         break;
 607                 case 's':
 608                         strip_padding = 1;
 609                         break;
 610                 case 'i':
 611                         inspect_info.file_name = optarg;
 612                         break;
 613                 case 'j':
 614                         add_jffs2_eof = 1;
 615                         break;
 616                 case 'x':
 617                         extract = 1;
 618                         break;
 619                 case 'e':
 620                         endian_swap = true;
 621                         break;
 622                 case 'h':
 623                         usage(EXIT_SUCCESS);
 624                         break;
 625                 case 'X':
 626                         sscanf(optarg, "0x%x", &reserved_space);
 627                         break;
 628                 default:
 629                         usage(EXIT_FAILURE);
 630                         break;
 631                 }
 632         }
 633
 634         ret = check_options();
 635         if (ret)
 636                 goto out;
 637
 638         if (!inspect_info.file_name)
 639                 ret = build_fw(sizeof(struct fw_header));
 640         else
 641                 ret = inspect_fw();
 642
 643  out:
 644         return ret;
 645 }