Merge bitcoin#31376: Miner: never create a template which exploits th…

…e timewarp bug

733fa0b miner: never create a template which exploits the timewarp bug (Antoine Poinsot)

Pull request description:

  This check was introduced in bitcoin#30681 but only enabled for testnet4. To avoid potentially creating an invalid block template if a soft fork to fix the timewarp attack were to activate in the future, we should have this check on all networks. It also seems wise for our miner to not support it whether or not a soft fork activates to fix it at the consensus level.

ACKs for top commit:
  Sjors:
    ACK 733fa0b
  fjahr:
    utACK 733fa0b
  TheCharlatan:
    ACK 733fa0b

Tree-SHA512: 9b3bc8b26a57f93425b17dda80bcfac4ecb750a3d26bc3eb8df619135634e369ac15982fac0c9770b1df207bd2e418ffe02a98f37968f024e55262d97715a4f5

src/node/miner.cpp

@@ -33,12 +33,10 @@ int64_t UpdateTime(CBlockHeader* pblock, const Consensus::Params& consensusParam
     int64_t nOldTime = pblock->nTime;
     int64_t nNewTime{std::max<int64_t>(pindexPrev->GetMedianTimePast() + 1, TicksSinceEpoch<std::chrono::seconds>(NodeClock::now()))};
 
-    if (consensusParams.enforce_BIP94) {
-        // Height of block to be mined.
-        const int height{pindexPrev->nHeight + 1};
-        if (height % consensusParams.DifficultyAdjustmentInterval() == 0) {
-            nNewTime = std::max<int64_t>(nNewTime, pindexPrev->GetBlockTime() - MAX_TIMEWARP);
-        }
+    // Height of block to be mined.
+    const int height{pindexPrev->nHeight + 1};
+    if (height % consensusParams.DifficultyAdjustmentInterval() == 0) {
+        nNewTime = std::max<int64_t>(nNewTime, pindexPrev->GetBlockTime() - MAX_TIMEWARP);
     }
 
     if (nOldTime < nNewTime) {