HF: Move block.proof.challenge to Consensus::Params::signblockScript

Since the scriptPubKey for signing blocks never changes, there's no
point in repeating it with every block header.

src/chainparams.cpp

@@ -20,13 +20,13 @@
 #include "chainparamsseeds.h"
 
 // Safer for users if they load incorrect parameters via arguments.
-static std::vector<unsigned char> CommitToArguments(const Consensus::Params& params, const std::string& networkID, const CScript& signblockscript)
+static std::vector<unsigned char> CommitToArguments(const Consensus::Params& params, const std::string& networkID)
 {
     CRIPEMD160 ripemd;
     unsigned char commitment[20];
     ripemd.Write((const unsigned char*)networkID.c_str(), networkID.length());
     ripemd.Write((const unsigned char*)HexStr(params.fedpegScript).c_str(), HexStr(params.fedpegScript).length());
-    ripemd.Write((const unsigned char*)HexStr(signblockscript).c_str(), HexStr(signblockscript).length());
+    ripemd.Write((const unsigned char*)HexStr(params.signblockScript).c_str(), HexStr(params.signblockScript).length());
     ripemd.Finalize(commitment);
     return std::vector<unsigned char>(commitment, commitment + 20);
 }
@@ -43,15 +43,15 @@ static CScript StrHexToScriptWithDefault(std::string strScript, const CScript de
     return returnScript;
 }
 
-static CBlock CreateGenesisBlock(const Consensus::Params& params, const std::string& networkID, const CScript& genesisOutputScript, uint32_t nTime, const CScript& scriptChallenge, int32_t nVersion, const CAmount& genesisReward, const uint32_t rewardShards)
+static CBlock CreateGenesisBlock(const Consensus::Params& params, const std::string& networkID, const CScript& genesisOutputScript, uint32_t nTime, int32_t nVersion, const CAmount& genesisReward, const uint32_t rewardShards)
 {
     // Shards must be evenly divisible
     assert(MAX_MONEY % rewardShards == 0);
     CMutableTransaction txNew;
     txNew.nVersion = 1;
     txNew.vin.resize(1);
     // Any consensus-related values that are command-line set can be added here for anti-footgun
-    txNew.vin[0].scriptSig = CScript(CommitToArguments(params, networkID, scriptChallenge));
+    txNew.vin[0].scriptSig = CScript(CommitToArguments(params, networkID));
     txNew.vout.resize(rewardShards);
     for (unsigned int i = 0; i < rewardShards; i++) {
         txNew.vout[i].nValue = genesisReward/rewardShards;
@@ -60,7 +60,7 @@ static CBlock CreateGenesisBlock(const Consensus::Params& params, const std::str
 
     CBlock genesis;
     genesis.nTime    = nTime;
-    genesis.proof = CProof(scriptChallenge, CScript());
+    genesis.proof = CProof(CScript());
     genesis.nVersion = nVersion;
     genesis.vtx.push_back(txNew);
     genesis.hashPrevBlock.SetNull();
@@ -85,7 +85,7 @@ class CElementsParams : public CChainParams {
         CScript defaultSignblockScript;
         // Default blocksign script for elements
         defaultSignblockScript = CScript() << OP_2 << ParseHex("03206b45265ae687dfdc602b8faa7dd749d7865b0e51f986e12c532229f0c998be") << ParseHex("02cc276552e180061f64dc16e2a02e7f9ecbcc744dea84eddbe991721824df825c") << ParseHex("0204c6be425356d9200a3303d95f2c39078cc9473ca49619da1e0ec233f27516ca") << OP_3 << OP_CHECKMULTISIG;
-        CScript genesisChallengeScript = StrHexToScriptWithDefault(GetArg("-signblockscript", "", mapArgs), defaultSignblockScript);
+        consensus.signblockScript = StrHexToScriptWithDefault(GetArg("-signblockscript", "", mapArgs), defaultSignblockScript);
         CScript defaultFedpegScript;
         defaultFedpegScript = CScript() << OP_2 << ParseHex("02d51090b27ca8f1cc04984614bd749d8bab6f2a3681318d3fd0dd43b2a39dd774") << ParseHex("03a75bd7ac458b19f98047c76a6ffa442e592148c5d23a1ec82d379d5d558f4fd8") << ParseHex("034c55bede1bce8e486080f8ebb7a0e8f106b49efb295a8314da0e1b1723738c66") << OP_3 << OP_CHECKMULTISIG;
         consensus.fedpegScript = StrHexToScriptWithDefault(GetArg("-fedpegscript", "", mapArgs), defaultFedpegScript);
@@ -138,7 +138,7 @@ class CElementsParams : public CChainParams {
 
         parentGenesisBlockHash = uint256S("000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943");
         CScript scriptDestination(CScript() << std::vector<unsigned char>(parentGenesisBlockHash.begin(), parentGenesisBlockHash.end()) << OP_WITHDRAWPROOFVERIFY);
-        genesis = CreateGenesisBlock(consensus, strNetworkID, scriptDestination, 1231006505, genesisChallengeScript, 1, MAX_MONEY, 100);
+        genesis = CreateGenesisBlock(consensus, strNetworkID, scriptDestination, 1231006505, 1, MAX_MONEY, 100);
         consensus.hashGenesisBlock = genesis.GetHash();
 
         scriptCoinbaseDestination = CScript() << ParseHex("0229536c4c83789f59c30b93eb40d4abbd99b8dcc99ba8bd748f29e33c1d279e3c") << OP_CHECKSIG;
@@ -206,7 +206,7 @@ class CRegTestParams : public CChainParams {
     void Reset(const std::map<std::string, std::string>& mapArgs)
     {
         const CScript defaultRegtestScript(CScript() << OP_TRUE);
-        CScript genesisChallengeScript = StrHexToScriptWithDefault(GetArg("-signblockscript", "", mapArgs), defaultRegtestScript);
+        consensus.signblockScript = StrHexToScriptWithDefault(GetArg("-signblockscript", "", mapArgs), defaultRegtestScript);
         consensus.fedpegScript = StrHexToScriptWithDefault(GetArg("-fedpegscript", "", mapArgs), defaultRegtestScript);
 
         strNetworkID = CHAINPARAMS_REGTEST;
@@ -241,7 +241,7 @@ class CRegTestParams : public CChainParams {
         nDefaultPort = 7042;
         nPruneAfterHeight = 1000;
 
-        genesis = CreateGenesisBlock(consensus, strNetworkID, defaultRegtestScript, 1296688602, genesisChallengeScript, 1, MAX_MONEY, 100);
+        genesis = CreateGenesisBlock(consensus, strNetworkID, defaultRegtestScript, 1296688602, 1, MAX_MONEY, 100);
         consensus.hashGenesisBlock = genesis.GetHash();
 
         parentGenesisBlockHash = uint256S("0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206");

src/consensus/params.h

@@ -64,6 +64,7 @@ struct Params {
     int64_t nPowTargetTimespan;
     int64_t DifficultyAdjustmentInterval() const { return nPowTargetTimespan / nPowTargetSpacing; }
     CScript fedpegScript;
+    CScript signblockScript;
 };
 } // namespace Consensus
 

src/pow.cpp

@@ -20,21 +20,20 @@
 #include "wallet/wallet.h"
 #endif
 
-CScript CombineBlockSignatures(const CBlockHeader& header, const CScript& scriptSig1, const CScript& scriptSig2)
+CScript CombineBlockSignatures(const Consensus::Params& params, const CBlockHeader& header, const CScript& scriptSig1, const CScript& scriptSig2)
 {
     SignatureData sig1(scriptSig1);
     SignatureData sig2(scriptSig2);
-    return GenericCombineSignatures(header.proof.challenge, header, sig1, sig2).scriptSig;
+    return GenericCombineSignatures(params.signblockScript, header, sig1, sig2).scriptSig;
 }
 
 bool CheckChallenge(const CBlockHeader& block, const CBlockIndex& indexLast, const Consensus::Params& params)
 {
-    return block.proof.challenge == indexLast.proof.challenge;
+    return true;
 }
 
 void ResetChallenge(CBlockHeader& block, const CBlockIndex& indexLast, const Consensus::Params& params)
 {
-    block.proof.challenge = indexLast.proof.challenge;
 }
 
 bool CheckBitcoinProof(const CBlockHeader& block)
@@ -62,14 +61,14 @@ bool CheckProof(const CBlockHeader& block, const Consensus::Params& params)
 {
     if (block.GetHash() == params.hashGenesisBlock)
        return true;
-    return GenericVerifyScript(block.proof.solution, block.proof.challenge, SCRIPT_VERIFY_P2SH, block);
+    return GenericVerifyScript(block.proof.solution, params.signblockScript, SCRIPT_VERIFY_P2SH, block);
 }
 
-bool MaybeGenerateProof(CBlockHeader *pblock, CWallet *pwallet)
+bool MaybeGenerateProof(const Consensus::Params& params, CBlockHeader *pblock, CWallet *pwallet)
 {
 #ifdef ENABLE_WALLET
     SignatureData solution(pblock->proof.solution);
-    bool res = GenericSignScript(*pwallet, *pblock, pblock->proof.challenge, solution);
+    bool res = GenericSignScript(*pwallet, *pblock, params.signblockScript, solution);
     pblock->proof.solution = solution.scriptSig;
     return res;
 #endif
@@ -86,16 +85,6 @@ double GetChallengeDifficulty(const CBlockIndex* blockindex)
     return 1;
 }
 
-std::string GetChallengeStr(const CBlockIndex& block)
-{
-    return ScriptToAsmStr(block.proof.challenge);
-}
-
-std::string GetChallengeStrHex(const CBlockIndex& block)
-{
-    return ScriptToAsmStr(block.proof.challenge);
-}
-
 uint32_t GetNonce(const CBlockHeader& block)
 {
     return 1;

src/pow.h

@@ -23,17 +23,15 @@ class uint256;
 bool CheckBitcoinProof(const CBlockHeader& block);
 bool CheckProof(const CBlockHeader& block, const Consensus::Params&);
 /** Scans nonces looking for a hash with at least some zero bits */
-bool MaybeGenerateProof(CBlockHeader* pblock, CWallet* pwallet);
+bool MaybeGenerateProof(const Consensus::Params& params, CBlockHeader* pblock, CWallet* pwallet);
 void ResetProof(CBlockHeader& block);
 bool CheckChallenge(const CBlockHeader& block, const CBlockIndex& indexLast, const Consensus::Params&);
 void ResetChallenge(CBlockHeader& block, const CBlockIndex& indexLast, const Consensus::Params&);
 
-CScript CombineBlockSignatures(const CBlockHeader& header, const CScript& scriptSig1, const CScript& scriptSig2);
+CScript CombineBlockSignatures(const Consensus::Params& params, const CBlockHeader& header, const CScript& scriptSig1, const CScript& scriptSig2);
 
 /** Avoid using these functions when possible */
 double GetChallengeDifficulty(const CBlockIndex* blockindex);
-std::string GetChallengeStr(const CBlockIndex& block);
-std::string GetChallengeStrHex(const CBlockIndex& block);
 uint32_t GetNonce(const CBlockHeader& block);
 void SetNonce(CBlockHeader& block, uint32_t nNonce);
 

src/primitives/block.cpp

@@ -19,8 +19,8 @@ std::string CBitcoinProof::ToString() const
 
 std::string CProof::ToString() const
 {
-    return strprintf("CProof(challenge=%s, solution=%s)",
-                     ScriptToAsmStr(challenge), ScriptToAsmStr(solution));
+    return strprintf("CProof(solution=%s)",
+                     ScriptToAsmStr(solution));
 }
 
 uint256 CBlockHeader::GetHash() const

src/primitives/block.h

@@ -51,34 +51,31 @@ class CBitcoinProof
 class CProof
 {
 public:
-    CScript challenge;
     CScript solution;
 
     CProof()
     {
         SetNull();
     }
-    CProof(CScript challengeIn, CScript solutionIn) : challenge(challengeIn), solution(solutionIn) {}
+    CProof(CScript solutionIn) : solution(solutionIn) {}
 
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>
     inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion)
     {
-        READWRITE(*(CScriptBase*)(&challenge));
         if (!(nType & SER_GETHASH))
             READWRITE(*(CScriptBase*)(&solution));
     }
 
     void SetNull()
     {
-        challenge.clear();
         solution.clear();
     }
 
     bool IsNull() const
     {
-        return challenge.empty();
+        return solution.empty();
     }
 
     std::string ToString() const;

src/rpc/blockchain.cpp

@@ -9,6 +9,7 @@
 #include "checkpoints.h"
 #include "coins.h"
 #include "consensus/validation.h"
+#include "core_io.h"
 #include "main.h"
 #include "policy/policy.h"
 #include "primitives/transaction.h"
@@ -62,7 +63,7 @@ UniValue blockheaderToJSON(const CBlockIndex* blockindex)
     result.push_back(Pair("time", (int64_t)blockindex->nTime));
     result.push_back(Pair("mediantime", (int64_t)blockindex->GetMedianTimePast()));
     result.push_back(Pair("nonce", (uint64_t)GetNonce(blockindex->GetBlockHeader())));
-    result.push_back(Pair("bits", GetChallengeStr(blockindex->GetBlockHeader())));
+    result.push_back(Pair("bits", ScriptToAsmStr(Params().GetConsensus().signblockScript)));
     result.push_back(Pair("difficulty", GetDifficulty(blockindex)));
     result.push_back(Pair("chainwork", blockindex->nChainWork.GetHex()));
 
@@ -106,7 +107,7 @@ UniValue blockToJSON(const CBlock& block, const CBlockIndex* blockindex, bool tx
     result.push_back(Pair("time", block.GetBlockTime()));
     result.push_back(Pair("mediantime", (int64_t)blockindex->GetMedianTimePast()));
     result.push_back(Pair("nonce", (uint64_t)GetNonce(block)));
-    result.push_back(Pair("bits", GetChallengeStr(block)));
+    result.push_back(Pair("bits", ScriptToAsmStr(Params().GetConsensus().signblockScript)));
     result.push_back(Pair("difficulty", GetDifficulty(blockindex)));
     result.push_back(Pair("chainwork", blockindex->nChainWork.GetHex()));
 

src/rpc/mining.cpp

@@ -211,14 +211,15 @@ UniValue combineblocksigs(const UniValue& params, bool fHelp)
         throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Block decode failed");
 
     UniValue result(UniValue::VOBJ);
+    const Consensus::Params& consensusParams = Params().GetConsensus();
     const UniValue& sigs = params[1].get_array();
     for (unsigned int i = 0; i < sigs.size(); i++) {
         const std::string& sig = sigs[i].get_str();
         if (!IsHex(sig))
             continue;
         std::vector<unsigned char> vchScript = ParseHex(sig);
-        block.proof.solution = CombineBlockSignatures(block, block.proof.solution, CScript(vchScript.begin(), vchScript.end()));
-        if (CheckProof(block, Params().GetConsensus())) {
+        block.proof.solution = CombineBlockSignatures(consensusParams, block, block.proof.solution, CScript(vchScript.begin(), vchScript.end()));
+        if (CheckProof(block, consensusParams)) {
             result.push_back(Pair("hex", EncodeHexBlock(block)));
             result.push_back(Pair("complete", true));
             return result;
@@ -662,6 +663,7 @@ UniValue getblocktemplate(const UniValue& params, bool fHelp)
     aMutable.push_back("transactions");
     aMutable.push_back("prevblock");
 
+    const std::string signblockStr = ScriptToAsmStr(Params().GetConsensus().signblockScript);
     UniValue result(UniValue::VOBJ);
     result.push_back(Pair("capabilities", aCaps));
 
@@ -725,7 +727,7 @@ UniValue getblocktemplate(const UniValue& params, bool fHelp)
     result.push_back(Pair("coinbaseaux", aux));
     result.push_back(Pair("coinbasevalue", (int64_t)pblock->vtx[0].vout[0].nValue.GetAmount()));
     result.push_back(Pair("longpollid", chainActive.Tip()->GetBlockHash().GetHex() + i64tostr(nTransactionsUpdatedLast)));
-    result.push_back(Pair("target", GetChallengeStrHex(*pblock)));
+    result.push_back(Pair("target", signblockStr));
     result.push_back(Pair("mintime", (int64_t)pindexPrev->GetMedianTimePast()+1));
     result.push_back(Pair("mutable", aMutable));
     result.push_back(Pair("noncerange", "00000000ffffffff"));
@@ -738,7 +740,7 @@ UniValue getblocktemplate(const UniValue& params, bool fHelp)
     result.push_back(Pair("sizelimit", (int64_t)MAX_BLOCK_SERIALIZED_SIZE));
     result.push_back(Pair("weightlimit", (int64_t)MAX_BLOCK_WEIGHT));
     result.push_back(Pair("curtime", pblock->GetBlockTime()));
-    result.push_back(Pair("bits", GetChallengeStr(*pblock)));
+    result.push_back(Pair("bits", signblockStr));
     result.push_back(Pair("height", (int64_t)(pindexPrev->nHeight+1)));
     if (!pblocktemplate->vchCoinbaseCommitment.empty()) {
         result.push_back(Pair("default_witness_commitment", HexStr(pblocktemplate->vchCoinbaseCommitment.begin(), pblocktemplate->vchCoinbaseCommitment.end())));

src/test/test_bitcoin.cpp

@@ -61,7 +61,7 @@ TestingSetup::TestingSetup(const std::string& chainName) : BasicTestingSetup(cha
         newCoinbase.vout[i].scriptPubKey = scriptPubKey;
     const_cast<CBlock&>(Params().GenesisBlock()).vtx[0] = newCoinbase;
     const_cast<CBlock&>(Params().GenesisBlock()).hashMerkleRoot = BlockMerkleRoot(Params().GenesisBlock());
-    const_cast<CBlock&>(Params().GenesisBlock()).proof = CProof(CScript()<<OP_TRUE, CScript());
+    const_cast<CBlock&>(Params().GenesisBlock()).proof = CProof(CScript());
     const_cast<Consensus::Params&>(Params().GetConsensus()).hashGenesisBlock = Params().GenesisBlock().GetHash();
 
         ClearDatadirCache();

src/wallet/rpcwallet.cpp

@@ -2694,7 +2694,7 @@ UniValue signblock(const UniValue& params, bool fHelp)
     }
 
     block.proof.solution = CScript();
-    MaybeGenerateProof(&block, pwalletMain);
+    MaybeGenerateProof(Params().GetConsensus(), &block, pwalletMain);
     return HexStr(block.proof.solution.begin(), block.proof.solution.end());
 }