Strip unneeded MTP data (#1089)

* Allow stripping of MTP data * Added arguments for MTP data srtipping testing * Remove one MTP test * Lifting strict rules preventing connection of older nodes * Version bump to 0.14.9.2 * MTP data strip time is set on testnet * Set date for MTP data stripping
firoorg · Nov 30, 2021 · 7de8050 · 7de8050
1 parent f8fd1a8
commit 7de8050
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Showing 9 changed files with 66 additions and 160 deletions.
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
@@ -134,7 +134,6 @@ BITCOIN_TESTS = \
   test/merkle_tests.cpp \
   test/miner_tests.cpp \
   test/mtp_halving_tests.cpp \
-  test/mtp_malformed_tests.cpp \
   test/mtp_tests.cpp \
   test/mtp_trans_tests.cpp \
   test/firopow_tests.cpp \

diff --git a/src/chainparams.cpp b/src/chainparams.cpp
@@ -275,6 +275,7 @@ class CMainParams : public CChainParams {
         consensus.nMTPSwitchTime = SWITCH_TO_MTP_BLOCK_HEADER;
         consensus.nMTPStartBlock = 117564;
         consensus.nMTPFiveMinutesStartBlock = SWITCH_TO_MTP_5MIN_BLOCK;
+        consensus.nMTPStripDataTime = 1638954000;   // December 08, 2021 09:00 UTC
 
         consensus.nDifficultyAdjustStartBlock = 0;
         consensus.nFixedDifficulty = 0x2000ffff;
@@ -567,6 +568,8 @@ class CTestNetParams : public CChainParams {
         consensus.nMTPSwitchTime = 1539172800;
         consensus.nMTPStartBlock = 1;
         consensus.nMTPFiveMinutesStartBlock = 0;
+        consensus.nMTPStripDataTime = 1636362000;      // November 08 2021, 09:00 UTC
+
         consensus.nDifficultyAdjustStartBlock = 100;
         consensus.nFixedDifficulty = 0x2000ffff;
         consensus.nPowTargetSpacingMTP = 5*60;
@@ -807,6 +810,8 @@ class CDevNetParams : public CChainParams {
         consensus.nMTPSwitchTime = 0;
         consensus.nMTPStartBlock = 1;
         consensus.nMTPFiveMinutesStartBlock = 0;
+        consensus.nMTPStripDataTime = INT_MAX;
+
         consensus.nDifficultyAdjustStartBlock = 800;
         consensus.nFixedDifficulty = 0x2000ffff;
         consensus.nPowTargetSpacingMTP = 5*60;
@@ -1012,6 +1017,8 @@ class CRegTestParams : public CChainParams {
         consensus.nMTPSwitchTime = INT_MAX;
         consensus.nMTPStartBlock = 0;
         consensus.nMTPFiveMinutesStartBlock = 0;
+        consensus.nMTPStripDataTime = INT_MAX;
+
         consensus.nDifficultyAdjustStartBlock = 5000;
         consensus.nFixedDifficulty = 0x207fffff;
         consensus.nPowTargetSpacingMTP = 5*60;

diff --git a/src/consensus/params.h b/src/consensus/params.h
@@ -319,6 +319,9 @@ struct Params {
     /** reduction coefficient for rewards after MTP kicks in */
     int nMTPRewardReduction;
 
+    /** after this time MTP data is stripped from all the outgoing blocks */
+    uint32_t nMTPStripDataTime;
+
     /** block number to disable zerocoin on consensus level */
     int nDisableZerocoinStartBlock;
 

diff --git a/src/init.cpp b/src/init.cpp
@@ -1688,16 +1688,26 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
         nMaxOutboundLimit = GetArg("-maxuploadtarget", DEFAULT_MAX_UPLOAD_TARGET)*1024*1024;
     }
 
-    // ********************************************************* Prepare ProgPow test in regtest mode
+    // ********************************************************* Prepare ProgPow/MTP tests
 
+    Consensus::Params &mutableParams = const_cast<Consensus::Params &>(Params().GetConsensus());
     if (Params().GetConsensus().IsRegtest()) {
-        Consensus::Params &mutableParams = const_cast<Consensus::Params &>(Params().GetConsensus());
         if (IsArgSet("-ppswitchtime"))
             mutableParams.nPPSwitchTime = GetArg("-ppswitchtime", INT_MAX);
         else if (IsArgSet("-ppswitchtimefromnow"))
             mutableParams.nPPSwitchTime = GetArg("-ppswitchtimefromnow", 0) + (uint32_t)GetTime();
+
+        if (IsArgSet("-mtpswitchtime"))
+            mutableParams.nMTPSwitchTime = GetArg("-mtpswitchtime", INT_MAX);
+        else if (IsArgSet("-mtpswitchtimefromnow"))
+            mutableParams.nMTPSwitchTime = GetArg("-mtpswitchtimefromnow", 0) + (uint32_t)GetTime();
     }
 
+    if (IsArgSet("-mtpstripdatatime"))
+        mutableParams.nMTPStripDataTime = GetArg("-mtpstripdatatime", INT_MAX);
+    else if (IsArgSet("-mtpstripdatatimefromnow"))
+        mutableParams.nMTPStripDataTime = GetArg("-mtpstripdatatimefromnow", 0) + (uint32_t)GetTime();
+
     // ********************************************************* Step 7a: check lite mode
 
     // lite mode disables all Dash-specific functionality

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
@@ -1091,6 +1091,20 @@ void static ProcessGetData(CNode* pfrom, const Consensus::Params& consensusParam
                     CBlock block;
                     if (!ReadBlockFromDisk(block, (*mi).second, consensusParams))
                         assert(!"cannot load block from disk");
+                    // Strip MTP data if past specific point of time
+                    if (!block.IsProgPow() && block.IsMTP() && GetTime() >= consensusParams.nMTPStripDataTime) {
+                        if (pfrom->nVersion >= MTPDATA_STRIPPED_VERSION) {
+                            if (block.mtpHashData)
+                                block.mtpHashData->StripMTPData();
+                        }
+                        else {
+                            // node is not ready for a block with stripped MTP data. Skip the block if MTP
+                            // data has already been stripped locally
+                            if (!block.mtpHashData || block.mtpHashData->IsMTPDataStripped())
+                                continue;
+                        }
+                    }
+
                     if (inv.type == MSG_BLOCK)
                         connman.PushMessage(pfrom, msgMaker.Make(SERIALIZE_TRANSACTION_NO_WITNESS, NetMsgType::BLOCK, block));
                     else if (inv.type == MSG_WITNESS_BLOCK)
@@ -2710,6 +2724,12 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();
         vRecv >> *pblock;
 
+        if (pblock->IsMTP() && !pblock->IsProgPow() && pblock->mtpHashData && GetTime() >= chainparams.GetConsensus().nMTPStripDataTime)
+        {
+            // we don't need MTP data anymore
+            pblock->mtpHashData->StripMTPData();
+        }
+
         LogPrint("net", "received block %s peer=%d\n", pblock->GetHash().ToString(), pfrom->id);
 
         // Process all blocks from whitelisted peers, even if not requested,

diff --git a/src/pow.cpp b/src/pow.cpp
@@ -155,8 +155,9 @@ bool CheckMerkleTreeProof(const CBlockHeader &block, const Consensus::Params &pa
     if (!block.IsMTP() || block.IsProgPow())
 	    return true;
 
-    if (!block.mtpHashData)
-        return false;
+    if (!block.mtpHashData || block.mtpHashData->IsMTPDataStripped())
+        // MTP data was stripped from the block, can't verify. Return true
+        return true;
 
     uint256 calculatedMtpHashValue;
     bool isVerified = mtp::verify(block.nNonce, block, Params().GetConsensus().powLimit, &calculatedMtpHashValue) &&

diff --git a/src/primitives/block.h b/src/primitives/block.h
@@ -52,9 +52,19 @@ class CMTPHashData {
     std::deque<std::vector<uint8_t>> nProofMTP[mtp::MTP_L*3];
 
     CMTPHashData() {
+        memset(hashRootMTP, 0, sizeof(hashRootMTP));
         memset(nBlockMTP, 0, sizeof(nBlockMTP));
     }
 
+    bool IsMTPDataStripped() const {
+        // if MTP data is stripped for this block hashRootMTP is all zeroes
+        return std::all_of(hashRootMTP, hashRootMTP+16, [](uint8_t b) {return b==0;});
+    }
+
+    void StripMTPData() {
+        memset(hashRootMTP, 0, sizeof(hashRootMTP));
+    }
+
     ADD_SERIALIZE_METHODS;
 
     /**
@@ -65,6 +75,9 @@ class CMTPHashData {
     template <typename Stream, typename Operation, typename = typename std::enable_if<!std::is_base_of<CSerActionUnserialize, Operation>::value>::type>
     inline void SerializationOp(Stream &s, Operation ser_action) {
         READWRITE(hashRootMTP);
+        if (IsMTPDataStripped())
+            return;
+
         READWRITE(nBlockMTP);
         for (int i = 0; i < mtp::MTP_L*3; i++) {
             assert(nProofMTP[i].size() < 256);
@@ -82,6 +95,10 @@ class CMTPHashData {
     template <typename Stream>
     inline void SerializationOp(Stream &s, CSerActionUnserialize ser_action) {
         READWRITE(hashRootMTP);
+
+        if (IsMTPDataStripped())
+            return;
+
         READWRITE(nBlockMTP);
         for (int i = 0; i < mtp::MTP_L*3; i++) {
             uint8_t numberOfProofBlocks;

diff --git a/src/test/mtp_malformed_tests.cpp b/src/test/mtp_malformed_tests.cpp
diff --git a/src/version.h b/src/version.h
@@ -9,7 +9,7 @@
  * network protocol versioning
  */
 
-static const int PROTOCOL_VERSION = 90030;
+static const int PROTOCOL_VERSION = 90031;
 
 //! legacy znode protocol version
 static const int LEGACY_ZNODES_PROTOCOL_VERSION = 90026;
@@ -60,4 +60,7 @@ static const int DMN_PROTO_VERSION = 90030;
 //! introduction of LLMQs
 static const int LLMQS_PROTO_VERSION = 90030;
 
+//! introducing blocks with stripped MTP data
+static const int MTPDATA_STRIPPED_VERSION = 90031;
+
 #endif // BITCOIN_VERSION_H