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

1.17 AuxPoW support

1 files changed, 165 insertions, 0 deletions

diff --git a/src/rpc/auxpow_miner.cpp b/src/rpc/auxpow_miner.cpp
new file mode 100644
index 000000000..3d6e93bac
--- /dev/null
+++ b/src/rpc/auxpow_miner.cpp
@@ -0,0 +1,165 @@
+// Copyright (c) 2018 Daniel Kraft
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <rpc/auxpow_miner.h>
+
+#include <arith_uint256.h>
+#include <auxpow.h>
+#include <chainparams.h>
+#include <net.h>
+#include <rpc/protocol.h>
+#include <utilstrencodings.h>
+#include <utiltime.h>
+#include <validation.h>
+
+#include <cassert>
+
+namespace
+{
+
+void auxMiningCheck()
+{
+  if (!g_connman)
+    throw JSONRPCError (RPC_CLIENT_P2P_DISABLED,
+                        "Error: Peer-to-peer functionality missing or"
+                        " disabled");
+
+  if (g_connman->GetNodeCount (CConnman::CONNECTIONS_ALL) == 0
+        && !Params ().MineBlocksOnDemand ())
+    throw JSONRPCError (RPC_CLIENT_NOT_CONNECTED,
+                        "Dogecoin is not connected!");
+
+  if (IsInitialBlockDownload () && !Params ().MineBlocksOnDemand ())
+    throw JSONRPCError (RPC_CLIENT_IN_INITIAL_DOWNLOAD,
+                        "Dogecoin is downloading blocks...");
+
+  /* This should never fail, since the chain is already
+     past the point of merge-mining start.  Check nevertheless.  */
+  {
+    LOCK (cs_main);
+    const auto auxpowStart = Params ().GetConsensus ().nAuxpowStartHeight;
+    if (chainActive.Height () + 1 < auxpowStart)
+      throw std::runtime_error ("mining auxblock method is not yet available");
+  }
+}
+
+}  // anonymous namespace
+
+const CBlock*
+AuxpowMiner::getCurrentBlock (const CScript& scriptPubKey, uint256& target)
+{
+  AssertLockHeld (cs);
+
+  {
+    LOCK (cs_main);
+    if (pindexPrev != chainActive.Tip ()
+        || (mempool.GetTransactionsUpdated () != txUpdatedLast
+            && GetTime () - startTime > 60))
+      {
+        if (pindexPrev != chainActive.Tip ())
+          {
+            /* Clear old blocks since they're obsolete now.  */
+            blocks.clear ();
+            templates.clear ();
+            pblockCur = nullptr;
+          }
+
+        /* Create new block with nonce = 0 and extraNonce = 1.  */
+        std::unique_ptr<CBlockTemplate> newBlock
+            = BlockAssembler (Params ()).CreateNewBlock (scriptPubKey);
+        if (newBlock == nullptr)
+          throw JSONRPCError (RPC_OUT_OF_MEMORY, "out of memory");
+
+        /* Update state only when CreateNewBlock succeeded.  */
+        txUpdatedLast = mempool.GetTransactionsUpdated ();
+        pindexPrev = chainActive.Tip ();
+        startTime = GetTime ();
+
+        /* Finalise it by setting the version and building the merkle root.  */
+        IncrementExtraNonce (&newBlock->block, pindexPrev, extraNonce);
+        newBlock->block.SetAuxpowFlag (true);
+
+        /* Save in our map of constructed blocks.  */
+        pblockCur = &newBlock->block;
+        blocks[pblockCur->GetHash ()] = pblockCur;
+        templates.push_back (std::move (newBlock));
+      }
+  }
+
+  /* At this point, pblockCur is always initialised:  If we make it here
+     without creating a new block above, it means that, in particular,
+     pindexPrev == chainActive.Tip().  But for that to happen, we must
+     already have created a pblockCur in a previous call, as pindexPrev is
+     initialised only when pblockCur is.  */
+  assert (pblockCur);
+
+  arith_uint256 arithTarget;
+  bool fNegative, fOverflow;
+  arithTarget.SetCompact (pblockCur->nBits, &fNegative, &fOverflow);
+  if (fNegative || fOverflow || arithTarget == 0)
+    throw std::runtime_error ("invalid difficulty bits in block");
+  target = ArithToUint256 (arithTarget);
+
+  return pblockCur;
+}
+
+const CBlock*
+AuxpowMiner::lookupSavedBlock (const std::string& hashHex) const
+{
+  AssertLockHeld (cs);
+
+  uint256 hash;
+  hash.SetHex (hashHex);
+
+  const auto iter = blocks.find (hash);
+  if (iter == blocks.end ())
+    throw JSONRPCError (RPC_INVALID_PARAMETER, "block hash unknown");
+
+  return iter->second;
+}
+
+UniValue
+AuxpowMiner::createAuxBlock (const CScript& scriptPubKey)
+{
+  auxMiningCheck ();
+  LOCK (cs);
+
+  uint256 target;
+  const CBlock* pblock = getCurrentBlock (scriptPubKey, target);
+
+  UniValue result(UniValue::VOBJ);
+  result.pushKV ("hash", pblock->GetHash ().GetHex ());
+  result.pushKV ("chainid", pblock->GetChainId ());
+  result.pushKV ("previousblockhash", pblock->hashPrevBlock.GetHex ());
+  result.pushKV ("coinbasevalue",
+                 static_cast<int64_t> (pblock->vtx[0]->vout[0].nValue));
+  result.pushKV ("bits", strprintf ("%08x", pblock->nBits));
+  result.pushKV ("height", static_cast<int64_t> (pindexPrev->nHeight + 1));
+  result.pushKV ("target", HexStr (BEGIN (target), END (target)));
+
+  return result;
+}
+
+bool
+AuxpowMiner::submitAuxBlock (const std::string& hashHex,
+                             const std::string& auxpowHex) const
+{
+  auxMiningCheck ();
+
+  std::shared_ptr<CBlock> shared_block;
+  {
+    LOCK (cs);
+    const CBlock* pblock = lookupSavedBlock (hashHex);
+    shared_block = std::make_shared<CBlock> (*pblock);
+  }
+
+  const std::vector<unsigned char> vchAuxPow = ParseHex (auxpowHex);
+  CDataStream ss(vchAuxPow, SER_GETHASH, PROTOCOL_VERSION);
+  std::unique_ptr<CAuxPow> pow(new CAuxPow ());
+  ss >> *pow;
+  shared_block->SetAuxpow (std::move (pow));
+  assert (shared_block->GetHash ().GetHex () == hashHex);
+
+  return ProcessNewBlock (Params (), shared_block, true, nullptr);
+}