+ 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, &lfsr);\r
+ printf("key> %x%x\n", (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF));\r
+ AddLogUint64(logHexFileName, "key> ", lfsr); \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(lfsr, 6, traceCard + blockShift + 10);\r
+ } else {\r
+ num_to_bytes(lfsr, 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(lfsr); // 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 ar_enc; // encrypted reader response\r
+ uint32_t at_enc; // encrypted tag response\r
+ */\r
+ if (traceCrypto1) {\r
+ crypto1_destroy(traceCrypto1);\r
+ }\r
+ ks2 = ar_enc ^ prng_successor(nt, 64);\r
+ ks3 = at_enc ^ prng_successor(nt, 96);\r
+ traceCrypto1 = lfsr_recovery64(ks2, ks3);\r