tools/firmware-utils/src/wrt400n.c

   1 /*
   2  * WRT400n - Firmware Generation Creator
   3  *
   4  * Creates a firmware image for the Linksys WRT400n router,
   5  * that can be uploaded via the firmware upload page,
   6  * from a kernel image file and root fs file
   7  *
   8  *      Author: Sandeep Mistry
   9  */
  10 #include <fcntl.h>
  11 #include <stdio.h>
  12 #include <stdint.h>
  13 #include <string.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16
  17 #include "cyg_crc.h"
  18
  19 // https://dev.openwrt.org/browser/trunk/target/linux/rdc-2.6/files/drivers/mtd/maps/rdc3210.c
  20 static uint32_t crctab[257] =
  21 {
  22         0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
  23         0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
  24         0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
  25         0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
  26         0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
  27         0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
  28         0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
  29         0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
  30         0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
  31         0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
  32         0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
  33         0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
  34         0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
  35         0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
  36         0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
  37         0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
  38         0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
  39         0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
  40         0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
  41         0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
  42         0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
  43         0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
  44         0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
  45         0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
  46         0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
  47         0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
  48         0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
  49         0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
  50         0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
  51         0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
  52         0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
  53         0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
  54         0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
  55         0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
  56         0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
  57         0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
  58         0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
  59         0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
  60         0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
  61         0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
  62         0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
  63         0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
  64         0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
  65         0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
  66         0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
  67         0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
  68         0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
  69         0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
  70         0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
  71         0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
  72         0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
  73         0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
  74         0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
  75         0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
  76         0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
  77         0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
  78         0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
  79         0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
  80         0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
  81         0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
  82         0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
  83         0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
  84         0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
  85         0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
  86         0
  87 };
  88
  89 static uint32_t crc32(uint8_t* buf, uint32_t len)
  90 {
  91         register int i;
  92         uint32_t sum;
  93         register uint32_t s0;
  94         s0 = ~0;
  95         for (i = 0; i < len; i++)
  96         {
  97                 s0 = (s0 >> 8) ^ crctab[(uint8_t) (s0 & 0xFF) ^ buf[i]];
  98         }
  99         sum = ~s0;
 100         return sum;
 101 }
 102
 103 #define HEADERSIZE      60
 104 #define MAGIC           "GMTKRT400N"
 105
 106 // global variables
 107 uint8_t kernelbuf[0x100000];    // kernel - lzma - uImage
 108 uint8_t rootfsbuf[0x2FFFC4];    // root - squashfs
 109
 110 uint8_t buf[0x400000];          // buffer for image
 111
 112
 113 // Header format:
 114 //
 115 //              GPL Tarball: http://downloads.linksysbycisco.com/downloads/WRT400N_1.0.01.19_US.tar,0.gz
 116 //              File: WRT400N_1.0.01.19_US/FW_WRT400N_1.0.01.19_US_20081229/GTK/user/include/fw_upgrade.h
 117 //
 118 //
 119 //              Struct:
 120 //                      typedef struct
 121 //                      {
 122 //                              UINT32          checksum;               /* CRC32 */
 123 //                              UINT8                   magic[11];              /* The value of GTIMG_MAGIC */
 124 //                              UINT32          kernel_length;          /* The length of the kernel image */
 125 //                              //UINT32                kernel_entry_point;     /* Kernel's entry point for RedBoot's information */
 126 //                              UINT32          kernel_upgrade_flag;    /* Set to 1 if we need to upgrade the kernel parition of the Flash */
 127 //                              UINT32          rootfs_length;          /* The length of the rootfs image */
 128 //                              //UINT32                rootfs_entry_point;     /* Not in use */
 129 //                              UINT32          rootfs_upgrade_flag;    /* Set to 1 if we need to upgrade the rootfs parition of the Flash */
 130 //
 131 //                              // Add 3 items by Vic Yu, 2006-05/10
 132 //                              UINT32          kernel_checksum;
 133 //                              UINT32          rootfs_checksum;
 134 //                              UINT32          fw_totalsize;
 135 //                              UINT32          reserved[4];
 136 //                      }imghdr_t , *pLinuxFWHeader_T;
 137 //
 138 //
 139 //              Description
 140 //                      - checksum:                     CRC32 of kernel and root fs, back to back
 141 //                      - magic:                                GMTKRT400N
 142 //                      - kernel_length:                kernel length in bytes
 143 //                      - kernel_upgrade_flag:  should we upgrade the kernel - set to 1
 144 //                      - rootfs_length:                root fs length in byte
 145 //                      - rootfs_upgrade_flag:  should we upgrade the root fs - set to 1
 146 //                      - kernel_checksum:              Gary S. Brown's 32 bit CRC algorithm for kernel, with remaining bits
 147 //                                                                      set to 0xFF upto 0x100000 bytes (total length)
 148 //                      - rootfs_checksum:              Gary S. Brown's 32 bit CRC algorithm for root fs, with remaining bits
 149 //                                                                      set to 0xFF upto 0x2FFFC4 bytes (total length)
 150 //                      - fw_totalsize:                 total firmware image file length (header length + kernel length + root fs length)
 151 //                      - reserved[4]:                  reserved ??? - set to all 0xFF
 152
 153
 154
 155 int main(int argc, char *argv[])
 156 {
 157         // file descriptors ...
 158         int             kernelfd                = -1;
 159         int             rootfsfd                        = -1;
 160         int                     outfd                   = -1;
 161
 162         char*           kernelfilename  = NULL;
 163         char*           rootfsfilename  = NULL;
 164         char*           outputfilename  = NULL;
 165
 166         // file sizes
 167         uint32_t        kernelsize              = 0;
 168         uint32_t        rootfssize              = 0;
 169         uint32_t        totalsize               = 0;
 170
 171         // header flags
 172         uint32_t        kernelflag              = 0;
 173         uint32_t        rootfsflag              = 0;
 174
 175         // checksums
 176         uint32_t        kernelchecksum  = 0;
 177         uint32_t        rootfschecksum  = 0;
 178         uint32_t        crc                             = 0;
 179
 180         if(argc != 4)
 181         {
 182                 printf("Usage:\n\t%s <kernel file> <rootfs file> <output file>\n", argv[0]);
 183                 return 1;
 184         }
 185
 186         kernelfilename = argv[1];
 187         rootfsfilename = argv[2];
 188         outputfilename = argv[3];
 189
 190         // Fill the kernel, rootfs, main buffer
 191         memset(kernelbuf, 0xFF, sizeof(kernelbuf));
 192         memset(rootfsbuf, 0xFF, sizeof(rootfsbuf));
 193         memset(buf, 0xFF, sizeof(buf));
 194
 195         // open the kernel ..
 196         kernelfd = open(kernelfilename, O_RDONLY);
 197
 198         if(kernelfd == -1)
 199         {
 200                 printf("Error: opening '%s'\n", kernelfilename);
 201                 goto done;
 202         }
 203
 204         // read in the kernel ...
 205         kernelsize = read(kernelfd, kernelbuf, sizeof(kernelbuf));
 206
 207         if(kernelsize == -1)
 208         {
 209                 printf("Error: reading '%s'\n", kernelfilename);
 210                 goto done;
 211         }
 212
 213         // calculate the kernel checksum ...
 214         kernelchecksum = cyg_crc32_accumulate(0, kernelbuf, sizeof(kernelbuf));
 215
 216         // print out stats
 217         printf("%s: size %d (0x%x), crc32 = 0x%x\n", kernelfilename, kernelsize, kernelsize, kernelchecksum);
 218
 219
 220         // open the root fs ..
 221         rootfsfd = open(rootfsfilename, O_RDONLY);
 222
 223         if(rootfsfd == -1)
 224         {
 225                 printf("Error: opening '%s'\n", rootfsfilename);
 226                 goto done;
 227         }
 228
 229         // read in the root fs ..
 230         rootfssize = read(rootfsfd, rootfsbuf, sizeof(rootfsbuf));
 231
 232         if(rootfssize == -1)
 233         {
 234                 printf("Error: reading '%s'\n", rootfsfilename);
 235                 goto done;
 236         }
 237
 238         // calculate the root fs checksum ...
 239         rootfschecksum = cyg_crc32_accumulate(0, rootfsbuf, sizeof(rootfsbuf));
 240
 241         // print out stats
 242         printf("%s: size %d (0x%x), crc32 = 0x%x\n", rootfsfilename, rootfssize, rootfssize, rootfschecksum);
 243
 244
 245         // now for the header ...
 246
 247         totalsize = HEADERSIZE;
 248
 249         // copy over kernel
 250         memcpy(buf + totalsize, kernelbuf, kernelsize);
 251         totalsize += kernelsize;
 252
 253         // copy over root fs
 254         memcpy(buf + totalsize, rootfsbuf, rootfssize);
 255         totalsize += rootfssize;
 256
 257         // calculate crc
 258         crc = crc32(buf + HEADERSIZE, totalsize - HEADERSIZE);
 259
 260         // print some stats out
 261         printf("crc = 0x%x, total size = %d (0x%x)\n", crc, totalsize, totalsize);
 262
 263         // copy crc into header
 264         crc = htonl(crc);
 265         memcpy(buf, &crc, sizeof(crc));
 266
 267         // copy over magic
 268         strcpy((char *)buf + 4, MAGIC);
 269
 270         // copy over kernel size
 271         kernelsize = htonl(kernelsize);
 272         memcpy(buf + 16, &kernelsize, sizeof(kernelsize));
 273
 274         // copy over kernal flag
 275         kernelflag = htonl(0x1);
 276         memcpy(buf + 20, &kernelflag, sizeof(kernelflag));
 277
 278         // copy over root fs size
 279         rootfssize = htonl(rootfssize);
 280         memcpy(buf + 24, &rootfssize, sizeof(rootfssize));
 281
 282         // copy over root fs flag
 283         rootfsflag = htonl(0x1);
 284         memcpy(buf + 28, &rootfsflag, sizeof(rootfsflag));
 285
 286         // copy over kernel check sum
 287         kernelchecksum = htonl(kernelchecksum);
 288         memcpy(buf + 32, &kernelchecksum, sizeof(kernelchecksum));
 289
 290         // copy over root fs checksum
 291         rootfschecksum = htonl(rootfschecksum);
 292         memcpy(buf + 36, &rootfschecksum, sizeof(rootfschecksum));
 293
 294         // copy over total size
 295         totalsize = htonl(totalsize);
 296         memcpy(buf + 40, &totalsize, sizeof(totalsize));
 297
 298         // undo the htonl (for write)
 299         totalsize = htonl(totalsize);
 300
 301
 302         // write out the file from the buffer
 303         outfd = open(outputfilename, O_CREAT | O_WRONLY | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
 304
 305         if(outfd == -1)
 306         {
 307                 printf("ERROR: opening '%s' for write\n", outputfilename);
 308         }
 309
 310         write(outfd, buf, totalsize);
 311
 312 done:
 313         // close open fd's
 314
 315         if(kernelfd != -1)
 316         {
 317                 close(kernelfd);
 318                 kernelfd = -1;
 319         }
 320
 321         if(rootfsfd != -1)
 322         {
 323                 close(rootfsfd);
 324                 rootfsfd = -1;
 325         }
 326
 327         if(outfd != -1)
 328         {
 329                 close(outfd);
 330                 outfd = -1;
 331         }
 332
 333         return 0;
 334 }