+ case TRACE_WRITE_OK: \r
+ if ((len == 1) && (data[0] == 0x0a)) {\r
+ traceState = TRACE_WRITE_DATA;\r
+\r
+ return 0;\r
+ } else {\r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+ break;\r
+\r
+ case TRACE_WRITE_DATA: \r
+ if (len == 18) {\r
+ traceState = TRACE_IDLE;\r
+\r
+ memcpy(traceCard + traceCurBlock * 16, data, 16);\r
+ if (wantSaveToEmlFile) saveTraceCard();\r
+ return 0;\r
+ } else {\r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+ break;\r
+\r
+ case TRACE_AUTH1: \r
+ if (len == 4) {\r
+ traceState = TRACE_AUTH2;\r
+ nt = bytes_to_num(data, 4);\r
+ return 0;\r
+ } else {\r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+ break;\r
+\r
+ case TRACE_AUTH2: \r
+ if (len == 8) {\r
+ traceState = TRACE_AUTH_OK;\r
+\r
+ nr_enc = bytes_to_num(data, 4);\r
+ ar_enc = bytes_to_num(data + 4, 4);\r
+ return 0;\r
+ } else {\r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+ break;\r
+\r
+ case TRACE_AUTH_OK: \r
+ if (len ==4) {\r
+ traceState = TRACE_IDLE;\r
+\r
+ at_enc = bytes_to_num(data, 4);\r
+ \r
+ // decode key here)\r
+ ks2 = ar_enc ^ prng_successor(nt, 64);\r
+ ks3 = at_enc ^ prng_successor(nt, 96);\r
+ revstate = lfsr_recovery64(ks2, ks3);\r
+ lfsr_rollback_word(revstate, 0, 0);\r
+ lfsr_rollback_word(revstate, 0, 0);\r
+ lfsr_rollback_word(revstate, nr_enc, 1);\r
+ lfsr_rollback_word(revstate, uid ^ nt, 0);\r
+\r
+ crypto1_get_lfsr(revstate, &key);\r
+ printf("Key: %012"llx"\n",key);\r
+ AddLogUint64(logHexFileName, "key: ", key); \r
+ \r
+ int blockShift = ((traceCurBlock & 0xFC) + 3) * 16;\r
+ if (isBlockEmpty((traceCurBlock & 0xFC) + 3)) memcpy(traceCard + blockShift + 6, trailerAccessBytes, 4);\r
+ \r
+ if (traceCurKey) {\r
+ num_to_bytes(key, 6, traceCard + blockShift + 10);\r
+ } else {\r
+ num_to_bytes(key, 6, traceCard + blockShift);\r
+ }\r
+ if (wantSaveToEmlFile) saveTraceCard();\r
+\r
+ if (traceCrypto1) {\r
+ crypto1_destroy(traceCrypto1);\r
+ }\r
+ \r
+ // set cryptosystem state\r
+ traceCrypto1 = lfsr_recovery64(ks2, ks3);\r
+ \r
+// nt = crypto1_word(traceCrypto1, nt ^ uid, 1) ^ nt;\r
+\r
+ /* traceCrypto1 = crypto1_create(key); // key in lfsr\r
+ crypto1_word(traceCrypto1, nt ^ uid, 0);\r
+ crypto1_word(traceCrypto1, ar, 1);\r
+ crypto1_word(traceCrypto1, 0, 0);\r
+ crypto1_word(traceCrypto1, 0, 0);*/\r
+ \r
+ return 0;\r
+ } else {\r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+ break;\r
+\r
+ default: \r
+ traceState = TRACE_ERROR;\r
+ return 1;\r
+ }\r
+\r
+ return 0;\r
+}\r
+\r
+int tryDecryptWord(uint32_t nt, uint32_t ar_enc, uint32_t at_enc, uint8_t *data, int len){\r
+ /*\r
+ uint32_t nt; // tag challenge\r
+ uint32_t nr_enc; // encrypted reader challenge\r
+ uint32_t ar_enc; // encrypted reader response\r
+ uint32_t at_enc; // encrypted tag response\r
+ */\r
+ struct Crypto1State *pcs = NULL;\r
+ \r
+ ks2 = ar_enc ^ prng_successor(nt, 64);\r
+ ks3 = at_enc ^ prng_successor(nt, 96);\r
+ \r
+ PrintAndLog("Decrypting data with:");\r
+ PrintAndLog(" nt: %08x",nt);\r
+ PrintAndLog(" ar_enc: %08x",ar_enc);\r
+ PrintAndLog(" at_enc: %08x",at_enc);\r
+ PrintAndLog("\nEncrypted data: [%s]", sprint_hex(data,len) );\r