+// call when PAR == 0, special attack?
+int nonce2key_ex(uint32_t uid, uint32_t nt, uint32_t nr, uint64_t ks_info, uint64_t * key) {
+ struct Crypto1State *state;
+ uint32_t i, pos, key_count;
+ byte_t ks3x[8];
+
+ uint64_t key_recovered;
+ int64_t *state_s;
+ static uint32_t last_uid;
+ static int64_t *last_keylist;
+
+ if (last_uid != uid && last_keylist != NULL) {
+ free(last_keylist);
+ last_keylist = NULL;
+ }
+ last_uid = uid;
+
+ // Reset the last three significant bits of the reader nonce
+ nr &= 0xffffff1f;
+
+ PrintAndLog("uid(%08x) nt(%08x) ks(%016"llx") nr(%08"llx")\n", uid, nt, ks_info, nr);
+
+ for (pos=0; pos<8; pos++) {
+ ks3x[7-pos] = (ks_info >> (pos*8)) & 0x0f;
+ }
+
+ PrintAndLog("parity is all zero,try special attack! just wait for few more seconds");
+
+ clock_t t1 = clock();
+
+ state = lfsr_common_prefix_ex(nr, ks3x);
+ state_s = (int64_t*)state;
+
+ //char filename[50] ;
+ //sprintf(filename, "nt_%08x_%d.txt", nt, nr);
+ //printf("name %s\n", filename);
+ //FILE* fp = fopen(filename,"w");
+ for (i = 0; (state) && ((state + i)->odd != -1); i++) {
+ lfsr_rollback_word(state+i, uid^nt, 0);
+ crypto1_get_lfsr(state + i, &key_recovered);
+ *(state_s + i) = key_recovered;
+ //fprintf(fp, "%012llx\n",key_recovered);
+ }
+ //fclose(fp);
+
+ if(!state)
+ return 1;
+
+ qsort(state_s, i, sizeof(*state_s), compar_int);
+ *(state_s + i) = -1;
+
+ //Create the intersection:
+ if ( last_keylist != NULL) {
+ int64_t *p1, *p2, *p3;
+ p1 = p3 = last_keylist;
+ p2 = state_s;
+ while ( *p1 != -1 && *p2 != -1 ) {
+ if (compar_int(p1, p2) == 0) {
+ printf("p1:%"llx" p2:%"llx" p3:%"llx" key:%012"llx"\n",(uint64_t)(p1-last_keylist),(uint64_t)(p2-state_s),(uint64_t)(p3-last_keylist),*p1);
+ *p3++ = *p1++;
+ p2++;
+ }
+ else {
+ while (compar_int(p1, p2) == -1) ++p1;
+ while (compar_int(p1, p2) == 1) ++p2;
+ }
+ }
+ key_count = p3 - last_keylist;;
+ } else {
+ key_count = 0;
+ }