Merge pull request #1546 from rnicoll/1.17-auxpow1.17-dev

1.17 AuxPoW support

1 files changed, 47 insertions, 9 deletions

diff --git a/src/validation.cpp b/src/validation.cpp
index c14db2454..0086d3911 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -6,6 +6,7 @@
 #include <validation.h>
 
 #include <arith_uint256.h>
+#include <auxpow.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <checkpoints.h>
@@ -1074,7 +1075,11 @@ static bool WriteBlockToDisk(const CBlock& block, CDiskBlockPos& pos, const CMes
     return true;
 }
 
-bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams)
+/* Generic implementation of block reading that can handle
+   both a block and its header.  */
+
+template<typename T>
+static bool ReadBlockOrHeader(T& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams)
 {
     block.SetNull();
 
@@ -1092,13 +1097,14 @@ bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus:
     }
 
     // Check the header
-    if (!CheckProofOfWork(block.GetPoWHash(), block.nBits, consensusParams))
+    if (!CheckAuxPowProofOfWork(block, consensusParams))
         return error("ReadBlockFromDisk: Errors in block header at %s", pos.ToString());
 
     return true;
 }
 
-bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams)
+template<typename T>
+static bool ReadBlockOrHeader(T& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams)
 {
     CDiskBlockPos blockPos;
     {
@@ -1106,7 +1112,7 @@ bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus
         blockPos = pindex->GetBlockPos();
     }
 
-    if (!ReadBlockFromDisk(block, blockPos, consensusParams))
+    if (!ReadBlockOrHeader(block, blockPos, consensusParams))
         return false;
     if (block.GetHash() != pindex->GetBlockHash())
         return error("ReadBlockFromDisk(CBlock&, CBlockIndex*): GetHash() doesn't match index for %s at %s",
@@ -1114,6 +1120,21 @@ bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus
     return true;
 }
 
+bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams)
+{
+    return ReadBlockOrHeader(block, pos, consensusParams);
+}
+
+bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams)
+{
+    return ReadBlockOrHeader(block, pindex, consensusParams);
+}
+
+bool ReadBlockHeaderFromDisk(CBlockHeader& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams)
+{
+    return ReadBlockOrHeader(block, pindex, consensusParams);
+}
+
 bool ReadRawBlockFromDisk(std::vector<uint8_t>& block, const CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& message_start)
 {
     CDiskBlockPos hpos = pos;
@@ -3080,7 +3101,7 @@ static bool FindUndoPos(CValidationState &state, int nFile, CDiskBlockPos &pos,
 static bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true)
 {
     // Check proof of work matches claimed amount
-    if (fCheckPOW && !CheckProofOfWork(block.GetPoWHash(), block.nBits, consensusParams))
+    if (fCheckPOW && !CheckAuxPowProofOfWork(block, consensusParams))
         return state.DoS(50, false, REJECT_INVALID, "high-hash", false, "proof of work failed");
 
     return true;
@@ -3231,6 +3252,22 @@ static bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationSta
     assert(pindexPrev != nullptr);
     const int nHeight = pindexPrev->nHeight + 1;
 
+    // Disallow legacy blocks after merge-mining start.
+    if (!Params().GetConsensus().AllowLegacyBlocks(nHeight)
+        && block.IsLegacy())
+        return state.DoS(100, error("%s : legacy block after auxpow start",
+                                    __func__),
+                         REJECT_INVALID, "late-legacy-block");
+
+    // Dogecoin: Disallow AuxPow blocks before it is activated.
+    // TODO: Remove this test, as checkpoints will enforce this for us now
+    // NOTE: Previously this had its own fAllowAuxPoW flag, but that's always the opposite of fAllowLegacyBlocks
+    if (Params().GetConsensus().AllowLegacyBlocks(nHeight)
+        && block.IsAuxpow())
+        return state.DoS(100, error("%s : auxpow blocks are not allowed at height %d",
+                                    __func__, pindexPrev->nHeight + 1),
+                         REJECT_INVALID, "early-auxpow-block");
+
     // Check proof of work
     const Consensus::Params& consensusParams = params.GetConsensus();
     if (block.nBits != GetNextWorkRequired(pindexPrev, &block, consensusParams))
@@ -3257,10 +3294,10 @@ static bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationSta
     // Reject outdated version blocks when 95% (75% on testnet) of the network has upgraded:
     // check for version 2, 3 and 4 upgrades
     // Dogecoin: Version 2 enforcement was never used
-    if((block.nVersion < 3 && nHeight >= consensusParams.BIP66Height) ||
-       (block.nVersion < 4 && nHeight >= consensusParams.BIP65Height))
-            return state.Invalid(false, REJECT_OBSOLETE, strprintf("bad-version(0x%08x)", block.nVersion),
-                                 strprintf("rejected nVersion=0x%08x block", block.nVersion));
+    if((block.GetBaseVersion() < 3 && nHeight >= consensusParams.BIP66Height) ||
+       (block.GetBaseVersion() < 4 && nHeight >= consensusParams.BIP65Height))
+            return state.Invalid(false, REJECT_OBSOLETE, strprintf("bad-version(0x%08x)", block.GetBaseVersion()),
+                                 strprintf("rejected nVersion=0x%08x block", block.GetBaseVersion()));
 
     return true;
 }
@@ -3276,6 +3313,7 @@ static bool ContextualCheckBlock(const CBlock& block, CValidationState& state, c
     const int nHeight = pindexPrev == nullptr ? 0 : pindexPrev->nHeight + 1;
 
     // Start enforcing BIP113 (Median Time Past) using versionbits logic.
+    // Dogecoin: We probably want to disable this
     int nLockTimeFlags = 0;
     if (VersionBitsState(pindexPrev, consensusParams, Consensus::DEPLOYMENT_CSV, versionbitscache) == ThresholdState::ACTIVE) {
         nLockTimeFlags |= LOCKTIME_MEDIAN_TIME_PAST;