} else {                                        // add new entry at end of existing list.
                        p2 = p2->next = malloc(sizeof(noncelistentry_t));
                }
-       } else if ((p1->nonce_enc & 0x00ff0000) != (nonce_enc & 0x00ff0000)) {                          // found distinct 2nd byte. Need to insert.
+               if (p2 == NULL) return 0;                                                       // memory allocation failed
+       }
+       else if ((p1->nonce_enc & 0x00ff0000) != (nonce_enc & 0x00ff0000)) {                    // found distinct 2nd byte. Need to insert.
                if (p2 == NULL) {                       // need to insert at start of list
                        p2 = nonces[first_byte].first = malloc(sizeof(noncelistentry_t));
                } else {
                        p2 = p2->next = malloc(sizeof(noncelistentry_t));
                }
-       } else {                                                                                        // we have seen this 2nd byte before. Nothing to add or insert. 
-               return (0);
+               if (p2 == NULL) return 0;                                                       // memory allocation failed
+       } else {
+               return 0;                                                                       // we have seen this 2nd byte before. Nothing to add or insert.
        }
 
        // add or insert new data
        nonces[first_byte].Sum += evenparity32((nonce_enc & 0x00ff0000) | (par_enc & 0x04));
        nonces[first_byte].updated = true;   // indicates that we need to recalculate the Sum(a8) probability for this first byte
 
-       return (1);                             // new nonce added
+       return 1;                               // new nonce added
 }
 
 static void init_nonce_memory(void)
                
 }
 
-static void    free_candidates_memory(statelist_t *sl)
-{
-       if (sl == NULL) {
-               return;
-       } else {
-               free_candidates_memory(sl->next);
-               free(sl);
-       }
-}
-
 static int acquire_nonces(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, bool nonce_file_write, bool slow)
 {
-       uint8_t three_in_row = 0;
-       uint8_t prev_best = 0;
        clock_t time1 = clock();
        bool initialize = true;
        bool finished = false;
        uint32_t next_fivehundred = 500;
        uint32_t total_added_nonces = 0;
        uint32_t idx = 1;
+       uint32_t timeout  = 0;
        FILE *fnonces = NULL;
        field_off = false;
        UsbCommand resp;
        do {
        
                flags = 0;
-               //flags |= initialize ? 0x0001 : 0;
-               flags |= 0x0001;
+               flags |= initialize ? 0x0001 : 0;
                flags |= slow ? 0x0002 : 0;
                flags |= field_off ? 0x0004 : 0;
                c.arg[2] = flags;
                
                if (field_off) break;
 
-               if (!WaitForResponseTimeout(CMD_ACK, &resp, 6000)) {
-                       if (fnonces) fclose(fnonces);
-                       return 1;
-               }
+               while(!WaitForResponseTimeout(CMD_ACK, &resp, 2000)) {
+                       timeout++;
+                       printf(".");
+                       if (timeout > 3) {
+                               PrintAndLog("\nNo response from Proxmark. Aborting...");
+                               if (fnonces) fclose(fnonces);
+                               return 1;
+                       }
+               }               
 
                if (resp.arg[0]) {
                        if (fnonces) fclose(fnonces);
                                        );                              
                        }
                        
-                       if ( num_good_first_bytes > 0 ) {
-                               
-                               if ( prev_best == best_first_bytes[0] ){
-                                       ++three_in_row;
-                               } else {
-                                       three_in_row = 0;
-                               }
-                               prev_best = best_first_bytes[0];
-                               
-                               //printf("GOOD BYTES: %s \n", sprint_hex(best_first_bytes, num_good_first_bytes) );
-                               if ( total_added_nonces >= (NONCES_THRESHOLD * idx) || three_in_row >= 3) {
-                                       
-                                       bool cracking = generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess);
-                                       if (cracking || known_target_key != -1) {
-                                               
-                                               UsbCommand cOff = {CMD_FPGA_MAJOR_MODE_OFF, {0,0,0} };
-                                               SendCommand(&cOff);
-                                               field_off = brute_force();
+                       if (total_added_nonces >= (NONCES_THRESHOLD * idx)) {
+                               if (num_good_first_bytes > 0) {
+                                       if (generate_candidates(first_byte_Sum, nonces[best_first_bytes[0]].Sum8_guess) || known_target_key != -1) {
+                                               field_off = brute_force(); // switch off field with next SendCommand and then finish
                                        }
-                                       three_in_row = 0;
                                }
+                               idx++;
                        }
-                       
-                       if ( total_added_nonces >= (NONCES_THRESHOLD * idx)) 
-                                       ++idx;
                }
        } while (!finished);
 
        uint32_t state_odd = pcs->odd & 0x00ffffff;
        uint32_t state_even = pcs->even & 0x00ffffff;
        //printf("Tests: searching for key %llx after first byte 0x%02x (state_odd = 0x%06x, state_even = 0x%06x) ...\n", key, best_first_bytes[0], state_odd, state_even);
-       printf("Validating keysearch space\n");
-       if ( candidates == NULL ) {
-                       printf("candidates list is NULL\n");
-                       return false;
-       }
+       printf("Validating key search space\n");
        uint64_t count = 0;
        for (statelist_t *p = candidates; p != NULL; p = p->next) {
                bool found_odd = false;
        return false;
 }
 
+static void free_candidates_memory(statelist_t *sl)
+{
+       if (sl == NULL) {
+               return;
+       } else {
+               free_candidates_memory(sl->next);
+               free(sl);
+       }
+}
+
 static void free_statelist_cache(void)
 {
        for (uint16_t i = 0; i < 17; i+=2) {
             const uint64_t key = crack_states_bitsliced(bucket);
 
                        if (keys_found) break;
-                       else if(key != -1 && TestIfKeyExists(key)) {
+                       else if(key != -1) {
+                               if (TestIfKeyExists(key)) {
                 __sync_fetch_and_add(&keys_found, 1);
                                __sync_fetch_and_add(&foundkey, key);
+                                       printf("*");
+                                       fflush(stdout);
                 break;
+                               }
+                               printf("!");
+                               fflush(stdout);
             } else {                           
                 printf(".");
                                fflush(stdout);
             }
         }
-
         current_bucket += thread_count;
     }
-
     return NULL;
 }
 
        return ret;
 }
 
-int mfnestedhard(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *trgkey, bool nonce_file_read, bool nonce_file_write, bool slow, int tests) 
+int mfnestedhard(uint8_t blockNo, uint8_t keyType, uint8_t *key, uint8_t trgBlockNo, uint8_t trgKeyType, uint8_t *trgkey, bool nonce_file_read, bool nonce_file_write, bool slow, int tests, uint64_t *found_key) 
 {
        // initialize Random number generator
        time_t t;
        srand((unsigned) time(&t));
        
+       *found_key = 0;
+       
        if (trgkey != NULL) {
                known_target_key = bytes_to_num(trgkey, 6);
        } else {
                } else { // acquire nonces.
                        uint16_t is_OK = acquire_nonces(blockNo, keyType, key, trgBlockNo, trgKeyType, nonce_file_write, slow);
                        if (is_OK != 0) {
+                               free_nonces_memory();
+                               //free_statelist_cache();
+                               free_candidates_memory(candidates);
+                               candidates = NULL;
                                return is_OK;
                        }
                }
                free_candidates_memory(candidates);
                candidates = NULL;
        }
+       *found_key = foundkey;
        return 0;
-}
+}
\ No newline at end of file