tools/iriver.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2004 by Dave Hooper
  11  *
  12  * This particular source code file is licensed under the X11 license. See the
  13  * bottom of the COPYING file for details on this license.
  14  *
  15  * Original code from http://www.beermex.com/@spc/ihpfirm.src.zip
  16  * Details at http://www.rockbox.org/twiki/bin/view/Main/IriverToolsGuide
  17  *
  18  ****************************************************************************/
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include "iriver.h"
  24
  25 const unsigned char munge[] = {
  26   0x7a, 0x36, 0xc4, 0x43, 0x49, 0x6b, 0x35, 0x4e, 0xa3, 0x46, 0x25, 0x84,
  27   0x4d, 0x73, 0x74, 0x61
  28 };
  29
  30 const unsigned char header_modify[] = "* IHPFIRM-DECODED ";
  31
  32 const char * const models[] = { "iHP-100", "iHP-120/iHP-140", "H300 series",
  33                                 NULL };
  34
  35 /* aligns with models array;  expected min firmware size */
  36 const unsigned int firmware_minsize[] = { 0x100000, 0x100000, 0x200000 };
  37 /* aligns with models array;  expected max firmware size */
  38 const unsigned int firmware_maxsize[] = { 0x200000, 0x200000, 0x400000 };
  39
  40 const unsigned char header[][16] = {
  41   { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 },
  42   { 0x20, 0x03, 0x08, 0x27, 0x24, 0x00, 0x02, 0x30, 0x19, 0x17, 0x65, 0x73,
  43     0x85, 0x32, 0x83, 0x22 },
  44   { 0x20, 0x04, 0x03, 0x27, 0x20, 0x50, 0x01, 0x70, 0x80, 0x30, 0x80, 0x06,
  45     0x30, 0x19, 0x17, 0x65 }
  46 };
  47
  48 static int testheader( const unsigned char * const data )
  49 {
  50     const unsigned char * const d = data+16;
  51     const char * const * m = models;
  52     int index = 0;
  53     while( *m )
  54     {
  55         if( memcmp( header[ index ], d, 16 ) == 0 )
  56             return index;
  57         index++;
  58         m++;
  59     };
  60     return -1;
  61 };
  62
  63 static void modifyheader( unsigned char * data )
  64 {
  65     const unsigned char * h = header_modify;
  66     int i;
  67     for( i=0; i<512; i++ )
  68     {
  69         if( *h == '\0' )
  70             h = header_modify;
  71         *data++ ^= *h++;
  72     };
  73 };
  74
  75 static FILE * openinfile( const char * filename )
  76 {
  77     FILE * F = fopen( filename, "rb" );
  78     if( F == NULL )
  79     {
  80         fprintf( stderr, "Couldn't open input file %s\n", filename );
  81         perror( "Error was " );
  82         exit( -1 );
  83     };
  84     return F;
  85 };
  86
  87 static FILE * openoutfile( const char * filename )
  88 {
  89     FILE * F = fopen( filename, "wb" );
  90     if( F == NULL )
  91     {
  92         fprintf( stderr, "Couldn't open output file %s\n", filename );
  93         perror( "Error was " );
  94         exit( -1 );
  95     };
  96     return F;
  97 };
  98
  99 int iriver_decode(char *infile_name, char *outfile_name, BOOL modify,
 100                   enum striptype stripmode )
 101 {
 102     FILE * infile = NULL;
 103     FILE * outfile = NULL;
 104     int i = -1;
 105     unsigned char headerdata[512];
 106     unsigned long dwLength1, dwLength2, dwLength3, fp = 0;
 107     unsigned char blockdata[16+16];
 108     unsigned char out[16];
 109     unsigned char newmunge;
 110     signed long lenread;
 111     int s = 0;
 112     unsigned char * pChecksums, * ppChecksums = 0;
 113     unsigned char ck;
 114
 115     infile = openinfile(infile_name);
 116     outfile = openoutfile(outfile_name);
 117
 118     lenread = fread( headerdata, 1, 512, infile );
 119     if( lenread != 512 )
 120     {
 121         fprintf( stderr, "This doesn't look like a valid encrypted iHP "
 122                  "firmware - reason: header length\n" );
 123         exit( -1 );
 124     };
 125
 126     i = testheader( headerdata );
 127     if( i == -1 )
 128     {
 129         fprintf( stderr, "This firmware is for an unknown model, or is not"
 130                  " a valid encrypted iHP firmware\n" );
 131         exit( -1 );
 132     };
 133     fprintf( stderr, "Model %s\n", models[ i ] );
 134
 135     dwLength1 = headerdata[0] | (headerdata[1]<<8) |
 136         (headerdata[2]<<16) | (headerdata[3]<<24);
 137     dwLength2 = headerdata[4] | (headerdata[5]<<8) |
 138         (headerdata[6]<<16) | (headerdata[7]<<24);
 139     dwLength3 = headerdata[8] | (headerdata[9]<<8) |
 140         (headerdata[10]<<16) | (headerdata[11]<<24);
 141
 142     if( dwLength1 < firmware_minsize[ i ] ||
 143         dwLength1 > firmware_maxsize[ i ] ||
 144         dwLength2 < firmware_minsize[ i ] ||
 145         dwLength2 > dwLength1 ||
 146         dwLength3 > dwLength1 ||
 147         dwLength2>>9 != dwLength3 ||
 148         dwLength2+dwLength3+512 != dwLength1 )
 149     {
 150         fprintf( stderr, "This doesn't look like a valid encrypted "
 151                  "iHP firmware - reason: file 'length' data\n" );
 152         exit( -1 );
 153     };
 154
 155     pChecksums = ppChecksums = (unsigned char *)( malloc( dwLength3 ) );
 156
 157     if( modify )
 158     {
 159         modifyheader( headerdata );
 160     };
 161
 162     if( stripmode == STRIP_NONE )
 163         fwrite( headerdata, 512, 1, outfile );
 164
 165     memset( blockdata, 0, 16 );
 166
 167     ck = 0;
 168     while( ( fp < dwLength2 ) &&
 169            ( lenread = fread( blockdata+16, 1, 16, infile ) ) == 16 )
 170     {
 171         fp += 16;
 172
 173         for( i=0; i<16; ++i )
 174         {
 175             newmunge = blockdata[16+i] ^ munge[i];
 176             out[i] = newmunge ^ blockdata[i];
 177             blockdata[i] = newmunge;
 178             ck += out[i];
 179         }
 180
 181         if( fp > ESTF_SIZE || stripmode != STRIP_HEADER_CHECKSUM_ESTF )
 182         {
 183             fwrite( out+4, 1, 12, outfile );
 184             fwrite( out, 1, 4, outfile );
 185         }
 186         else
 187         {
 188             if( ESTF_SIZE - fp < 16 )
 189             {
 190                 memcpy( out+4, blockdata+16, 12 );
 191                 memcpy( out, blockdata+28, 4 );
 192                 fwrite( blockdata+16+ESTF_SIZE-fp, 1, ESTF_SIZE-fp, outfile );
 193             }
 194         }
 195
 196
 197         if( s == 496 )
 198         {
 199             s = 0;
 200             memset( blockdata, 0, 16 );
 201             *ppChecksums++ = ck;
 202             ck = 0;
 203         }
 204         else
 205             s+=16;
 206     };
 207
 208     if( fp != dwLength2 )
 209     {
 210         fprintf( stderr, "This doesn't look like a valid encrypted "
 211                  "iHP firmware - reason: 'length2' mismatch\n" );
 212         exit( -1 );
 213     };
 214
 215     fp = 0;
 216     ppChecksums = pChecksums;
 217     while( ( fp < dwLength3 ) &&
 218            ( lenread = fread( blockdata, 1, 32, infile ) ) > 0 )
 219     {
 220         fp += lenread;
 221         if( stripmode == STRIP_NONE )
 222             fwrite( blockdata, 1, lenread, outfile );
 223         if( memcmp( ppChecksums, blockdata, lenread ) != 0 )
 224         {
 225             fprintf( stderr, "This doesn't look like a valid encrypted "
 226                      "iHP firmware - reason: Checksum mismatch!" );
 227             exit( -1 );
 228         };
 229         ppChecksums += lenread;
 230     };
 231
 232     if( fp != dwLength3 )
 233     {
 234         fprintf( stderr, "This doesn't look like a valid encrypted "
 235                  "iHP firmware - reason: 'length3' mismatch\n" );
 236         exit( -1 );
 237     };
 238
 239
 240     fprintf( stderr, "File decoded correctly and all checksums matched!\n" );
 241     switch( stripmode )
 242     {
 243         default:
 244         case STRIP_NONE:
 245             fprintf(stderr, "Output file contains all headers and "
 246                     "checksums\n");
 247             break;
 248         case STRIP_HEADER_CHECKSUM:
 249             fprintf( stderr, "NB:  output file contains only ESTFBINR header"
 250                      " and decoded firmware code\n" );
 251             break;
 252         case STRIP_HEADER_CHECKSUM_ESTF:
 253             fprintf( stderr, "NB:  output file contains only raw decoded "
 254                      "firmware code\n" );
 255             break;
 256     };
 257
 258     return 0;
 259 };
 260
 261 int iriver_encode(char *infile_name, char *outfile_name, BOOL modify )
 262 {
 263     FILE * infile = NULL;
 264     FILE * outfile = NULL;
 265     int i = -1;
 266     unsigned char headerdata[512];
 267     unsigned long dwLength1, dwLength2, dwLength3, fp = 0;
 268     unsigned char blockdata[16+16];
 269     unsigned char out[16];
 270     unsigned char newmunge;
 271     signed long lenread;
 272     int s = 0;
 273     unsigned char * pChecksums, * ppChecksums;
 274     unsigned char ck;
 275
 276     enum striptype stripmode = STRIP_NONE;
 277
 278     infile = openinfile(infile_name);
 279     outfile = openoutfile(outfile_name);
 280
 281     lenread = fread( headerdata, 1, 512, infile );
 282     if( lenread != 512 )
 283     {
 284         fprintf( stderr, "This doesn't look like a valid decoded "
 285                  "iHP firmware - reason: header length\n" );
 286         exit( -1 );
 287     };
 288
 289     if( modify )
 290     {
 291         modifyheader( headerdata ); /* reversible */
 292     };
 293
 294     i = testheader( headerdata );
 295     if( i == -1 )
 296     {
 297         fprintf( stderr, "This firmware is for an unknown model, or is not"
 298                  " a valid decoded iHP firmware\n" );
 299         exit( -1 );
 300     };
 301     fprintf( stderr, "Model %s\n", models[ i ] );
 302
 303     dwLength1 = headerdata[0] | (headerdata[1]<<8) |
 304         (headerdata[2]<<16) | (headerdata[3]<<24);
 305     dwLength2 = headerdata[4] | (headerdata[5]<<8) |
 306         (headerdata[6]<<16) | (headerdata[7]<<24);
 307     dwLength3 = headerdata[8] | (headerdata[9]<<8) |
 308         (headerdata[10]<<16) | (headerdata[11]<<24);
 309
 310     if( dwLength1 < firmware_minsize[i] ||
 311         dwLength1 > firmware_maxsize[i] ||
 312         dwLength2 < firmware_minsize[i] ||
 313         dwLength2 > dwLength1 ||
 314         dwLength3 > dwLength1 ||
 315         dwLength2+dwLength3+512 != dwLength1 )
 316     {
 317         fprintf( stderr, "This doesn't look like a valid decoded iHP"
 318                  " firmware - reason: file 'length' data\n" );
 319         exit( -1 );
 320     };
 321
 322     pChecksums = ppChecksums = (unsigned char *)( malloc( dwLength3 ) );
 323
 324     fwrite( headerdata, 512, 1, outfile );
 325
 326     memset( blockdata, 0, 16 );
 327     ck = 0;
 328     while( ( fp < dwLength2 ) &&
 329            ( lenread = fread( blockdata+16, 1, 16, infile ) ) == 16 )
 330     {
 331         fp += 16;
 332         for( i=0; i<16; ++i )
 333         {
 334             newmunge = blockdata[16+((12+i)&0xf)] ^ blockdata[i];
 335             out[i] = newmunge ^ munge[i];
 336             ck += blockdata[16+i];
 337             blockdata[i] = newmunge;
 338         };
 339         fwrite( out, 1, 16, outfile );
 340
 341         if( s == 496 )
 342         {
 343             s = 0;
 344             memset( blockdata, 0, 16 );
 345             *ppChecksums++ = ck;
 346             ck = 0;
 347         }
 348         else
 349             s+=16;
 350     };
 351
 352     if( fp != dwLength2 )
 353     {
 354         fprintf( stderr, "This doesn't look like a valid decoded "
 355                  "iHP firmware - reason: 'length1' mismatch\n" );
 356         exit( -1 );
 357     };
 358
 359     /* write out remainder w/out applying descrambler */
 360     fp = 0;
 361     lenread = dwLength3;
 362     ppChecksums = pChecksums;
 363     while( ( fp < dwLength3) &&
 364            ( lenread = fwrite( ppChecksums, 1, lenread, outfile ) ) > 0 )
 365     {
 366         fp += lenread;
 367         ppChecksums += lenread;
 368         lenread = dwLength3 - fp;
 369     };
 370
 371     if( fp != dwLength3 )
 372     {
 373         fprintf( stderr, "This doesn't look like a valid decoded "
 374                  "iHP firmware - reason: 'length2' mismatch\n" );
 375         exit( -1 );
 376     };
 377
 378     fprintf( stderr, "File encoded successfully and checksum table built!\n" );
 379
 380     return 0;
 381 };