fix: change valid vote minute from 2-3 to 3

Only allow the vote to be added on the 3rd minute of the hour, as this mitigates a potential attack where a user could vote for a known block producer at the top of the hour and get the staking rewards

src/cryptonote_config.h

@@ -217,7 +217,6 @@ full_addrs.insert(SEED_NODE_5);
 
 // Blockchain
 #define HF_VERSION_PROOF_OF_STAKE 13
-//#define HF_BLOCK_HEIGHT_PROOF_OF_STAKE 521850 // The first block of the X-CASH proof of stake
 #define HF_BLOCK_HEIGHT_PROOF_OF_STAKE 760000 // The first block of the X-CASH proof of stake
 #define BLOCK_TIME 5 // the block time in minutes
 #define BLOCKS_PER_DAY_FIVE_MINUTE_BLOCK_TIME 288 // The blocks per day with a 5 minute block time
@@ -421,3 +420,4 @@ namespace cryptonote
   };
 }
 
+

src/simplewallet/simplewallet.cpp

@@ -2286,7 +2286,7 @@ void sync_minutes_and_seconds(const int SETTINGS)
       std::this_thread::sleep_for(std::chrono::milliseconds(200));
       current_date_and_time = std::time(0);
       current_UTC_date_and_time = std::gmtime(&current_date_and_time);
-    } while (current_UTC_date_and_time->tm_min != 2); 
+    } while (current_UTC_date_and_time->tm_min != 3); 
   }
 
   // wait a random amount of time, so all messages from delegates that have been waiting dont get sent at the same time

src/wallet/api/wallet.cpp

@@ -2331,7 +2331,7 @@ void sync_minutes_and_seconds(const int SETTINGS)
       std::this_thread::sleep_for(std::chrono::milliseconds(200));
       current_date_and_time = std::time(0);
       current_UTC_date_and_time = std::gmtime(&current_date_and_time);
-    } while (current_UTC_date_and_time->tm_min != 2); 
+    } while (current_UTC_date_and_time->tm_min != 3); 
   }
 
   // wait a random amount of time, so all messages from delegates that have been waiting dont get sent at the same time

src/wallet/wallet_rpc_server.cpp

@@ -3409,7 +3409,7 @@ void sync_minutes_and_seconds(const int SETTINGS)
       std::this_thread::sleep_for(std::chrono::milliseconds(200));
       current_date_and_time = std::time(0);
       current_UTC_date_and_time = std::gmtime(&current_date_and_time);
-    } while (current_UTC_date_and_time->tm_min != 2); 
+    } while (current_UTC_date_and_time->tm_min != 3); 
   }
 
   // wait a random amount of time, so all messages from delegates that have been waiting dont get sent at the same time