1 files changed, 48 insertions, 3 deletions
diff --git a/src/dogecoin.cpp b/src/dogecoin.cpp
index e946acad6..dd394d5b4 100644
--- a/src/dogecoin.cpp
+++ b/src/dogecoin.cpp
@@ -21,9 +21,9 @@ unsigned int CalculateDogecoinNextWorkRequired(const CBlockIndex* pindexLast, in
     int nHeight = pindexLast->nHeight + 1;
     bool fNewDifficultyProtocol = (nHeight >= 145000);
     // bool fNewDifficultyProtocol = (nHeight >= params.GetDigiShieldForkBlock());
-    const int64_t retargetTimespan = fNewDifficultyProtocol
-                             ? 60 // params.DigiShieldTargetTimespan()
-                             : params.nPowTargetTimespan;
+    const int64_t retargetTimespan = fNewDifficultyProtocol ? 60 // params.DigiShieldTargetTimespan()
+                                                              :
+                                                              params.nPowTargetTimespan;
 
     const int64_t nActualTimespan = pindexLast->GetBlockTime() - nFirstBlockTime;
     int64_t nModulatedTimespan = nActualTimespan;
@@ -75,6 +75,51 @@ unsigned int CalculateDogecoinNextWorkRequired(const CBlockIndex* pindexLast, in
     return bnNew.GetCompact();
 }
 
+bool CheckAuxPowProofOfWork(const CBlockHeader& block, const Consensus::Params& params)
+{
+    /* Except for legacy blocks with full version 1, ensure that
+       the chain ID is correct.  Legacy blocks are not allowed since
+       the merge-mining start, which is checked in AcceptBlockHeader
+       where the height is known.  */
+    if (!block.nVersion.IsLegacy() && params.fStrictChainId && block.nVersion.GetChainId() != params.nAuxpowChainId)
+        return error("%s : block does not have our chain ID"
+                     " (got %d, expected %d, full nVersion %d)",
+                     __func__,
+                     block.nVersion.GetChainId(),
+                     params.nAuxpowChainId,
+                     block.nVersion.GetFullVersion());
+
+    /* If there is no auxpow, just check the block hash.  */
+    if (!block.auxpow) {
+        if (block.nVersion.IsAuxpow())
+            return error("%s : no auxpow on block with auxpow version",
+                         __func__);
+
+        if (!CheckProofOfWork(block.GetPoWHash(), block.nBits, params))
+            return error("%s : non-AUX proof of work failed", __func__);
+
+        return true;
+    }
+
+    /* We have auxpow.  Check it.  */
+
+    if (!block.nVersion.IsAuxpow())
+        return error("%s : auxpow on block with non-auxpow version", __func__);
+
+    /* Temporary check:  Disallow parent blocks with auxpow version.  This is
+       for compatibility with the old client.  */
+    /* FIXME: Remove this check with a hardfork later on.  */
+    if (block.auxpow->getParentBlock().nVersion.IsAuxpow())
+        return error("%s : auxpow parent block has auxpow version", __func__);
+
+    if (!block.auxpow->check(block.GetHash(), block.nVersion.GetChainId(), params))
+        return error("%s : AUX POW is not valid", __func__);
+    if (!CheckProofOfWork(block.auxpow->getParentBlockPoWHash(), block.nBits, params))
+        return error("%s : AUX proof of work failed", __func__);
+
+    return true;
+}
+
 CAmount GetDogecoinBlockSubsidy(int nHeight, const Consensus::Params& consensusParams, uint256 prevHash)
 {
     int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;