src/decss/CSSauth.cpp

   1 #include "stdafx.h"
   2
   3 static void CSSengine(int varient,unsigned char const *input,unsigned char *output);
   4
   5 void CSSkey1(int varient,unsigned char const *challenge,unsigned char *key)
   6 {
   7         static unsigned char perm_challenge[] = {1,3,0,7,5, 2,9,6,4,8};
   8
   9         unsigned char scratch[10];
  10         int i;
  11
  12         for (i = 9; i >= 0; --i)
  13                 scratch[i] = challenge[perm_challenge[i]];
  14
  15         CSSengine(varient, scratch, key);
  16 }
  17
  18 void CSSkey2(int varient,unsigned char const *challenge,unsigned char *key)
  19 {
  20         static unsigned char perm_challenge[] = {6,1,9,3,8, 5,7,4,0,2};
  21
  22         static unsigned char perm_varient[] = {
  23                 0x0a, 0x08, 0x0e, 0x0c, 0x0b, 0x09, 0x0f, 0x0d,
  24                 0x1a, 0x18, 0x1e, 0x1c, 0x1b, 0x19, 0x1f, 0x1d,
  25                 0x02, 0x00, 0x06, 0x04, 0x03, 0x01, 0x07, 0x05,
  26                 0x12, 0x10, 0x16, 0x14, 0x13, 0x11, 0x17, 0x15};
  27
  28         unsigned char scratch[10];
  29         int i;
  30
  31         for (i = 9; i >= 0; --i)
  32                 scratch[i] = challenge[perm_challenge[i]];
  33
  34         CSSengine(perm_varient[varient], scratch, key);
  35 }
  36
  37 void CSSbuskey(int varient,unsigned char const *challenge,unsigned char *key)
  38 {
  39         static unsigned char perm_challenge[] = {4,0,3,5,7, 2,8,6,1,9};
  40         static unsigned char perm_varient[] = {
  41                 0x12, 0x1a, 0x16, 0x1e, 0x02, 0x0a, 0x06, 0x0e,
  42                 0x10, 0x18, 0x14, 0x1c, 0x00, 0x08, 0x04, 0x0c,
  43                 0x13, 0x1b, 0x17, 0x1f, 0x03, 0x0b, 0x07, 0x0f,
  44                 0x11, 0x19, 0x15, 0x1d, 0x01, 0x09, 0x05, 0x0d};
  45
  46         unsigned char scratch[10];
  47         int i;
  48
  49         for (i = 9; i >= 0; --i)
  50                 scratch[i] = challenge[perm_challenge[i]];
  51
  52         CSSengine(perm_varient[varient], scratch, key);
  53 }
  54
  55 static void CSSgenbits(unsigned char *output, int len,unsigned char const *s)
  56 {
  57         unsigned long lfsr0, lfsr1;
  58         unsigned char b1_combined; /* Save the old value of bit 1 for feedback */
  59
  60         /* In order to ensure that the LFSR works we need to ensure that the
  61          * initial values are non-zero.  Thus when we initialise them from
  62          * the seed,  we ensure that a bit is set.
  63          */
  64         lfsr0 = (s[0] << 17) | (s[1] << 9) | ((s[2] & ~7) << 1) | 8 | (s[2] & 7);
  65         lfsr1 = (s[3] << 9) | 0x100 | s[4];
  66
  67         ++output;
  68
  69         b1_combined = 0;
  70         do {
  71                 int bit;
  72                 unsigned char val;
  73
  74                 for (bit = 0, val = 0; bit < 8; ++bit) {
  75                         unsigned char o_lfsr0, o_lfsr1; /* Actually only 1 bit each */
  76                         unsigned char combined;
  77
  78                         o_lfsr0 = ((lfsr0 >> 24) ^ (lfsr0 >> 21) ^ (lfsr0 >> 20) ^ (lfsr0 >> 12)) & 1;
  79                           lfsr0 = (lfsr0 << 1) | o_lfsr0;
  80
  81                         o_lfsr1 = ((lfsr1 >> 16) ^ (lfsr1 >> 2)) & 1;
  82                           lfsr1 = (lfsr1 << 1) | o_lfsr1;
  83
  84 #define  BIT0(x) ((x) & 1)
  85 #define  BIT1(x) (((x) >> 1) & 1)
  86
  87                         combined = !o_lfsr1 + b1_combined + !o_lfsr0;
  88                         b1_combined = BIT1(combined);
  89                         val |= BIT0(combined) << bit;
  90                 }
  91
  92                 *--output = val;
  93         } while (--len > 0);
  94 }
  95
  96 unsigned char CSSsecret[];
  97 unsigned char CSSvarients[];
  98 unsigned char CSStable0[];
  99 unsigned char CSStable1[];
 100 unsigned char CSStable2[];
 101 unsigned char CSStable3[];
 102
 103 static void CSSengine(int varient, unsigned char const *input,unsigned char *output)
 104 {
 105         unsigned char cse, term, index;
 106         unsigned char temp1[5];
 107         unsigned char temp2[5];
 108         unsigned char bits[30];
 109
 110         int i;
 111
 112         /* Feed the CSSsecret into the input values such that
 113          * we alter the seed to the LFSR's used above,  then
 114          * generate the bits to play with.
 115          */
 116         for (i = 5; --i >= 0; )
 117                 temp1[i] = input[5 + i] ^ CSSsecret[i] ^ CSStable2[i];
 118
 119         CSSgenbits(&bits[29], sizeof bits, temp1);
 120
 121         /* This term is used throughout the following to
 122          * select one of 32 different variations on the
 123          * algorithm.
 124          */
 125         cse = CSSvarients[varient] ^ CSStable2[varient];
 126
 127         /* Now the actual blocks doing the encryption.  Each
 128          * of these works on 40 bits at a time and are quite
 129          * similar.
 130          */
 131         for (i = 5, term = 0; --i >= 0; term = input[i]) {
 132                 index = bits[25 + i] ^ input[i];
 133                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 134
 135                 temp1[i] = CSStable2[index] ^ CSStable3[index] ^ term;
 136         }
 137         temp1[4] ^= temp1[0];
 138
 139         for (i = 5, term = 0; --i >= 0; term = temp1[i]) {
 140                 index = bits[20 + i] ^ temp1[i];
 141                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 142
 143                 temp2[i] = CSStable2[index] ^ CSStable3[index] ^ term;
 144         }
 145         temp2[4] ^= temp2[0];
 146
 147         for (i = 5, term = 0; --i >= 0; term = temp2[i]) {
 148                 index = bits[15 + i] ^ temp2[i];
 149                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 150                 index = CSStable2[index] ^ CSStable3[index] ^ term;
 151
 152                 temp1[i] = CSStable0[index] ^ CSStable2[index];
 153         }
 154         temp1[4] ^= temp1[0];
 155
 156         for (i = 5, term = 0; --i >= 0; term = temp1[i]) {
 157                 index = bits[10 + i] ^ temp1[i];
 158                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 159
 160                 index = CSStable2[index] ^ CSStable3[index] ^ term;
 161
 162                 temp2[i] = CSStable0[index] ^ CSStable2[index];
 163         }
 164         temp2[4] ^= temp2[0];
 165
 166         for (i = 5, term = 0; --i >= 0; term = temp2[i]) {
 167                 index = bits[5 + i] ^ temp2[i];
 168                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 169
 170                 temp1[i] = CSStable2[index] ^ CSStable3[index] ^ term;
 171         }
 172         temp1[4] ^= temp1[0];
 173
 174         for (i = 5, term = 0; --i >= 0; term = temp1[i]) {
 175                 index = bits[i] ^ temp1[i];
 176                 index = CSStable1[index] ^ ~CSStable2[index] ^ cse;
 177
 178                 output[i] = CSStable2[index] ^ CSStable3[index] ^ term;
 179         }
 180 }
 181
 182 static unsigned char CSSvarients[] = {
 183         0xB7, 0x74, 0x85, 0xD0, 0xCC, 0xDB, 0xCA, 0x73,
 184         0x03, 0xFE, 0x31, 0x03, 0x52, 0xE0, 0xB7, 0x42,
 185         0x63, 0x16, 0xF2, 0x2A, 0x79, 0x52, 0xFF, 0x1B,
 186         0x7A, 0x11, 0xCA, 0x1A, 0x9B, 0x40, 0xAD, 0x01};
 187
 188 static unsigned char CSSsecret[] = {0x55, 0xD6, 0xC4, 0xC5, 0x28};
 189
 190 static unsigned char CSStable0[] = {
 191         0xB7, 0xF4, 0x82, 0x57, 0xDA, 0x4D, 0xDB, 0xE2,
 192         0x2F, 0x52, 0x1A, 0xA8, 0x68, 0x5A, 0x8A, 0xFF,
 193         0xFB, 0x0E, 0x6D, 0x35, 0xF7, 0x5C, 0x76, 0x12,
 194         0xCE, 0x25, 0x79, 0x29, 0x39, 0x62, 0x08, 0x24,
 195         0xA5, 0x85, 0x7B, 0x56, 0x01, 0x23, 0x68, 0xCF,
 196         0x0A, 0xE2, 0x5A, 0xED, 0x3D, 0x59, 0xB0, 0xA9,
 197         0xB0, 0x2C, 0xF2, 0xB8, 0xEF, 0x32, 0xA9, 0x40,
 198         0x80, 0x71, 0xAF, 0x1E, 0xDE, 0x8F, 0x58, 0x88,
 199         0xB8, 0x3A, 0xD0, 0xFC, 0xC4, 0x1E, 0xB5, 0xA0,
 200         0xBB, 0x3B, 0x0F, 0x01, 0x7E, 0x1F, 0x9F, 0xD9,
 201         0xAA, 0xB8, 0x3D, 0x9D, 0x74, 0x1E, 0x25, 0xDB,
 202         0x37, 0x56, 0x8F, 0x16, 0xBA, 0x49, 0x2B, 0xAC,
 203         0xD0, 0xBD, 0x95, 0x20, 0xBE, 0x7A, 0x28, 0xD0,
 204         0x51, 0x64, 0x63, 0x1C, 0x7F, 0x66, 0x10, 0xBB,
 205         0xC4, 0x56, 0x1A, 0x04, 0x6E, 0x0A, 0xEC, 0x9C,
 206         0xD6, 0xE8, 0x9A, 0x7A, 0xCF, 0x8C, 0xDB, 0xB1,
 207         0xEF, 0x71, 0xDE, 0x31, 0xFF, 0x54, 0x3E, 0x5E,
 208         0x07, 0x69, 0x96, 0xB0, 0xCF, 0xDD, 0x9E, 0x47,
 209         0xC7, 0x96, 0x8F, 0xE4, 0x2B, 0x59, 0xC6, 0xEE,
 210         0xB9, 0x86, 0x9A, 0x64, 0x84, 0x72, 0xE2, 0x5B,
 211         0xA2, 0x96, 0x58, 0x99, 0x50, 0x03, 0xF5, 0x38,
 212         0x4D, 0x02, 0x7D, 0xE7, 0x7D, 0x75, 0xA7, 0xB8,
 213         0x67, 0x87, 0x84, 0x3F, 0x1D, 0x11, 0xE5, 0xFC,
 214         0x1E, 0xD3, 0x83, 0x16, 0xA5, 0x29, 0xF6, 0xC7,
 215         0x15, 0x61, 0x29, 0x1A, 0x43, 0x4F, 0x9B, 0xAF,
 216         0xC5, 0x87, 0x34, 0x6C, 0x0F, 0x3B, 0xA8, 0x1D,
 217         0x45, 0x58, 0x25, 0xDC, 0xA8, 0xA3, 0x3B, 0xD1,
 218         0x79, 0x1B, 0x48, 0xF2, 0xE9, 0x93, 0x1F, 0xFC,
 219         0xDB, 0x2A, 0x90, 0xA9, 0x8A, 0x3D, 0x39, 0x18,
 220         0xA3, 0x8E, 0x58, 0x6C, 0xE0, 0x12, 0xBB, 0x25,
 221         0xCD, 0x71, 0x22, 0xA2, 0x64, 0xC6, 0xE7, 0xFB,
 222         0xAD, 0x94, 0x77, 0x04, 0x9A, 0x39, 0xCF, 0x7C};
 223
 224 static unsigned char CSStable1[] = {
 225         0x8C, 0x47, 0xB0, 0xE1, 0xEB, 0xFC, 0xEB, 0x56,
 226         0x10, 0xE5, 0x2C, 0x1A, 0x5D, 0xEF, 0xBE, 0x4F,
 227         0x08, 0x75, 0x97, 0x4B, 0x0E, 0x25, 0x8E, 0x6E,
 228         0x39, 0x5A, 0x87, 0x53, 0xC4, 0x1F, 0xF4, 0x5C,
 229         0x4E, 0xE6, 0x99, 0x30, 0xE0, 0x42, 0x88, 0xAB,
 230         0xE5, 0x85, 0xBC, 0x8F, 0xD8, 0x3C, 0x54, 0xC9,
 231         0x53, 0x47, 0x18, 0xD6, 0x06, 0x5B, 0x41, 0x2C,
 232         0x67, 0x1E, 0x41, 0x74, 0x33, 0xE2, 0xB4, 0xE0,
 233         0x23, 0x29, 0x42, 0xEA, 0x55, 0x0F, 0x25, 0xB4,
 234         0x24, 0x2C, 0x99, 0x13, 0xEB, 0x0A, 0x0B, 0xC9,
 235         0xF9, 0x63, 0x67, 0x43, 0x2D, 0xC7, 0x7D, 0x07,
 236         0x60, 0x89, 0xD1, 0xCC, 0xE7, 0x94, 0x77, 0x74,
 237         0x9B, 0x7E, 0xD7, 0xE6, 0xFF, 0xBB, 0x68, 0x14,
 238         0x1E, 0xA3, 0x25, 0xDE, 0x3A, 0xA3, 0x54, 0x7B,
 239         0x87, 0x9D, 0x50, 0xCA, 0x27, 0xC3, 0xA4, 0x50,
 240         0x91, 0x27, 0xD4, 0xB0, 0x82, 0x41, 0x97, 0x79,
 241         0x94, 0x82, 0xAC, 0xC7, 0x8E, 0xA5, 0x4E, 0xAA,
 242         0x78, 0x9E, 0xE0, 0x42, 0xBA, 0x28, 0xEA, 0xB7,
 243         0x74, 0xAD, 0x35, 0xDA, 0x92, 0x60, 0x7E, 0xD2,
 244         0x0E, 0xB9, 0x24, 0x5E, 0x39, 0x4F, 0x5E, 0x63,
 245         0x09, 0xB5, 0xFA, 0xBF, 0xF1, 0x22, 0x55, 0x1C,
 246         0xE2, 0x25, 0xDB, 0xC5, 0xD8, 0x50, 0x03, 0x98,
 247         0xC4, 0xAC, 0x2E, 0x11, 0xB4, 0x38, 0x4D, 0xD0,
 248         0xB9, 0xFC, 0x2D, 0x3C, 0x08, 0x04, 0x5A, 0xEF,
 249         0xCE, 0x32, 0xFB, 0x4C, 0x92, 0x1E, 0x4B, 0xFB,
 250         0x1A, 0xD0, 0xE2, 0x3E, 0xDA, 0x6E, 0x7C, 0x4D,
 251         0x56, 0xC3, 0x3F, 0x42, 0xB1, 0x3A, 0x23, 0x4D,
 252         0x6E, 0x84, 0x56, 0x68, 0xF4, 0x0E, 0x03, 0x64,
 253         0xD0, 0xA9, 0x92, 0x2F, 0x8B, 0xBC, 0x39, 0x9C,
 254         0xAC, 0x09, 0x5E, 0xEE, 0xE5, 0x97, 0xBF, 0xA5,
 255         0xCE, 0xFA, 0x28, 0x2C, 0x6D, 0x4F, 0xEF, 0x77,
 256         0xAA, 0x1B, 0x79, 0x8E, 0x97, 0xB4, 0xC3, 0xF4};
 257
 258 static unsigned char CSStable2[] = {
 259         0xB7, 0x75, 0x81, 0xD5, 0xDC, 0xCA, 0xDE, 0x66,
 260         0x23, 0xDF, 0x15, 0x26, 0x62, 0xD1, 0x83, 0x77,
 261         0xE3, 0x97, 0x76, 0xAF, 0xE9, 0xC3, 0x6B, 0x8E,
 262         0xDA, 0xB0, 0x6E, 0xBF, 0x2B, 0xF1, 0x19, 0xB4,
 263         0x95, 0x34, 0x48, 0xE4, 0x37, 0x94, 0x5D, 0x7B,
 264         0x36, 0x5F, 0x65, 0x53, 0x07, 0xE2, 0x89, 0x11,
 265         0x98, 0x85, 0xD9, 0x12, 0xC1, 0x9D, 0x84, 0xEC,
 266         0xA4, 0xD4, 0x88, 0xB8, 0xFC, 0x2C, 0x79, 0x28,
 267         0xD8, 0xDB, 0xB3, 0x1E, 0xA2, 0xF9, 0xD0, 0x44,
 268         0xD7, 0xD6, 0x60, 0xEF, 0x14, 0xF4, 0xF6, 0x31,
 269         0xD2, 0x41, 0x46, 0x67, 0x0A, 0xE1, 0x58, 0x27,
 270         0x43, 0xA3, 0xF8, 0xE0, 0xC8, 0xBA, 0x5A, 0x5C,
 271         0x80, 0x6C, 0xC6, 0xF2, 0xE8, 0xAD, 0x7D, 0x04,
 272         0x0D, 0xB9, 0x3C, 0xC2, 0x25, 0xBD, 0x49, 0x63,
 273         0x8C, 0x9F, 0x51, 0xCE, 0x20, 0xC5, 0xA1, 0x50,
 274         0x92, 0x2D, 0xDD, 0xBC, 0x8D, 0x4F, 0x9A, 0x71,
 275         0x2F, 0x30, 0x1D, 0x73, 0x39, 0x13, 0xFB, 0x1A,
 276         0xCB, 0x24, 0x59, 0xFE, 0x05, 0x96, 0x57, 0x0F,
 277         0x1F, 0xCF, 0x54, 0xBE, 0xF5, 0x06, 0x1B, 0xB2,
 278         0x6D, 0xD3, 0x4D, 0x32, 0x56, 0x21, 0x33, 0x0B,
 279         0x52, 0xE7, 0xAB, 0xEB, 0xA6, 0x74, 0x00, 0x4C,
 280         0xB1, 0x7F, 0x82, 0x99, 0x87, 0x0E, 0x5E, 0xC0,
 281         0x8F, 0xEE, 0x6F, 0x55, 0xF3, 0x7E, 0x08, 0x90,
 282         0xFA, 0xB6, 0x64, 0x70, 0x47, 0x4A, 0x17, 0xA7,
 283         0xB5, 0x40, 0x8A, 0x38, 0xE5, 0x68, 0x3E, 0x8B,
 284         0x69, 0xAA, 0x9B, 0x42, 0xA5, 0x10, 0x01, 0x35,
 285         0xFD, 0x61, 0x9E, 0xE6, 0x16, 0x9C, 0x86, 0xED,
 286         0xCD, 0x2E, 0xFF, 0xC4, 0x5B, 0xA0, 0xAE, 0xCC,
 287         0x4B, 0x3B, 0x03, 0xBB, 0x1C, 0x2A, 0xAC, 0x0C,
 288         0x3F, 0x93, 0xC7, 0x72, 0x7A, 0x09, 0x22, 0x3D,
 289         0x45, 0x78, 0xA9, 0xA8, 0xEA, 0xC9, 0x6A, 0xF7,
 290         0x29, 0x91, 0xF0, 0x02, 0x18, 0x3A, 0x4E, 0x7C};
 291
 292 static unsigned char CSStable3[] = {
 293         0x73, 0x51, 0x95, 0xE1, 0x12, 0xE4, 0xC0, 0x58,
 294         0xEE, 0xF2, 0x08, 0x1B, 0xA9, 0xFA, 0x98, 0x4C,
 295         0xA7, 0x33, 0xE2, 0x1B, 0xA7, 0x6D, 0xF5, 0x30,
 296         0x97, 0x1D, 0xF3, 0x02, 0x60, 0x5A, 0x82, 0x0F,
 297         0x91, 0xD0, 0x9C, 0x10, 0x39, 0x7A, 0x83, 0x85,
 298         0x3B, 0xB2, 0xB8, 0xAE, 0x0C, 0x09, 0x52, 0xEA,
 299         0x1C, 0xE1, 0x8D, 0x66, 0x4F, 0xF3, 0xDA, 0x92,
 300         0x29, 0xB9, 0xD5, 0xC5, 0x77, 0x47, 0x22, 0x53,
 301         0x14, 0xF7, 0xAF, 0x22, 0x64, 0xDF, 0xC6, 0x72,
 302         0x12, 0xF3, 0x75, 0xDA, 0xD7, 0xD7, 0xE5, 0x02,
 303         0x9E, 0xED, 0xDA, 0xDB, 0x4C, 0x47, 0xCE, 0x91,
 304         0x06, 0x06, 0x6D, 0x55, 0x8B, 0x19, 0xC9, 0xEF,
 305         0x8C, 0x80, 0x1A, 0x0E, 0xEE, 0x4B, 0xAB, 0xF2,
 306         0x08, 0x5C, 0xE9, 0x37, 0x26, 0x5E, 0x9A, 0x90,
 307         0x00, 0xF3, 0x0D, 0xB2, 0xA6, 0xA3, 0xF7, 0x26,
 308         0x17, 0x48, 0x88, 0xC9, 0x0E, 0x2C, 0xC9, 0x02,
 309         0xE7, 0x18, 0x05, 0x4B, 0xF3, 0x39, 0xE1, 0x20,
 310         0x02, 0x0D, 0x40, 0xC7, 0xCA, 0xB9, 0x48, 0x30,
 311         0x57, 0x67, 0xCC, 0x06, 0xBF, 0xAC, 0x81, 0x08,
 312         0x24, 0x7A, 0xD4, 0x8B, 0x19, 0x8E, 0xAC, 0xB4,
 313         0x5A, 0x0F, 0x73, 0x13, 0xAC, 0x9E, 0xDA, 0xB6,
 314         0xB8, 0x96, 0x5B, 0x60, 0x88, 0xE1, 0x81, 0x3F,
 315         0x07, 0x86, 0x37, 0x2D, 0x79, 0x14, 0x52, 0xEA,
 316         0x73, 0xDF, 0x3D, 0x09, 0xC8, 0x25, 0x48, 0xD8,
 317         0x75, 0x60, 0x9A, 0x08, 0x27, 0x4A, 0x2C, 0xB9,
 318         0xA8, 0x8B, 0x8A, 0x73, 0x62, 0x37, 0x16, 0x02,
 319         0xBD, 0xC1, 0x0E, 0x56, 0x54, 0x3E, 0x14, 0x5F,
 320         0x8C, 0x8F, 0x6E, 0x75, 0x1C, 0x07, 0x39, 0x7B,
 321         0x4B, 0xDB, 0xD3, 0x4B, 0x1E, 0xC8, 0x7E, 0xFE,
 322         0x3E, 0x72, 0x16, 0x83, 0x7D, 0xEE, 0xF5, 0xCA,
 323         0xC5, 0x18, 0xF9, 0xD8, 0x68, 0xAB, 0x38, 0x85,
 324         0xA8, 0xF0, 0xA1, 0x73, 0x9F, 0x5D, 0x19, 0x0B,
 325         0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 326         0x33, 0x72, 0x39, 0x25, 0x67, 0x26, 0x6D, 0x71,
 327         0x36, 0x77, 0x3C, 0x20, 0x62, 0x23, 0x68, 0x74,
 328         0xC3, 0x82, 0xC9, 0x15, 0x57, 0x16, 0x5D, 0x81};