merge bitcoin#20295: getblockfrompeer

Author: kwvg

src/Makefile.am

@@ -287,12 +287,12 @@ BITCOIN_CORE_H = \
   rpc/blockchain.h \
   rpc/client.h \
   rpc/mining.h \
-  rpc/net.h \
   rpc/protocol.h \
   rpc/rawtransaction_util.h \
   rpc/register.h \
   rpc/request.h \
   rpc/server.h \
+  rpc/server_util.h \
   rpc/util.h \
   saltedhasher.h \
   scheduler.h \
@@ -510,6 +510,7 @@ libbitcoin_server_a_SOURCES = \
   rpc/quorums.cpp \
   rpc/rawtransaction.cpp \
   rpc/server.cpp \
+  rpc/server_util.cpp \
   script/sigcache.cpp \
   shutdown.cpp \
   spork.cpp \

src/net_processing.cpp

@@ -398,6 +398,7 @@ class PeerManagerImpl final : public PeerManager
 
     /** Implement PeerManager */
     void CheckForStaleTipAndEvictPeers() override;
+    bool FetchBlock(NodeId id, const uint256& hash, const CBlockIndex& index) override;
     bool GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats) const override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex);
     bool IgnoresIncomingTxs() override { return m_ignore_incoming_txs; }
     void SendPings() override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex);;
@@ -1862,6 +1863,39 @@ bool PeerManagerImpl::BlockRequestAllowed(const CBlockIndex* pindex)
         (GetBlockProofEquivalentTime(*pindexBestHeader, *pindex, *pindexBestHeader, m_chainparams.GetConsensus()) < STALE_RELAY_AGE_LIMIT);
 }
 
+bool PeerManagerImpl::FetchBlock(NodeId id, const uint256& hash, const CBlockIndex& index)
+{
+    if (fImporting || fReindex) return false;
+
+    LOCK(cs_main);
+    // Ensure this peer exists and hasn't been disconnected
+    CNodeState* state = State(id);
+    if (state == nullptr) return false;
+
+    // Mark block as in-flight unless it already is
+    if (!MarkBlockAsInFlight(id, index.GetBlockHash(), &index)) return false;
+
+    // Construct message to request the block
+    std::vector<CInv> invs{CInv(MSG_BLOCK, hash)};
+
+    // Send block request message to the peer
+    bool success = m_connman.ForNode(id, [this, &invs](CNode* node) {
+        const CNetMsgMaker msgMaker(node->GetCommonVersion());
+        this->m_connman.PushMessage(node, msgMaker.Make(NetMsgType::GETDATA, invs));
+        return true;
+    });
+
+    if (success) {
+        LogPrint(BCLog::NET, "Requesting block %s from peer=%d\n",
+                 hash.ToString(), id);
+    } else {
+        MarkBlockAsReceived(hash);
+        LogPrint(BCLog::NET, "Failed to request block %s from peer=%d\n",
+                 hash.ToString(), id);
+    }
+    return success;
+}
+
 std::unique_ptr<PeerManager> PeerManager::make(const CChainParams& chainparams, CConnman& connman, AddrMan& addrman, BanMan* banman,
                                                CScheduler &scheduler, ChainstateManager& chainman, CTxMemPool& pool,
                                                CMasternodeMetaMan& mn_metaman, CMasternodeSync& mn_sync,

src/net_processing.h

@@ -66,6 +66,16 @@ class PeerManager : public CValidationInterface, public NetEventsInterface
                                              const std::unique_ptr<LLMQContext>& llmq_ctx, bool ignore_incoming_txs);
     virtual ~PeerManager() { }
 
+    /**
+     * Attempt to manually fetch block from a given peer. We must already have the header.
+     *
+     * @param[in]  id       The peer id
+     * @param[in]  hash     The block hash
+     * @param[in]  pindex   The blockindex
+     * @returns             Whether a request was successfully made
+     */
+    virtual bool FetchBlock(NodeId id, const uint256& hash, const CBlockIndex& pindex) = 0;
+
     /** Get statistics from node state */
     virtual bool GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats) const = 0;
 

src/rest.cpp

@@ -19,6 +19,7 @@
 #include <rpc/blockchain.h>
 #include <rpc/protocol.h>
 #include <rpc/server.h>
+#include <rpc/server_util.h>
 #include <streams.h>
 #include <sync.h>
 #include <txmempool.h>

src/rpc/blockchain.cpp

@@ -22,13 +22,16 @@
 #include <llmq/context.h>
 #include <node/blockstorage.h>
 #include <node/coinstats.h>
+#include <net.h>
+#include <net_processing.h>
 #include <node/context.h>
 #include <node/utxo_snapshot.h>
 #include <policy/feerate.h>
 #include <policy/fees.h>
 #include <policy/policy.h>
 #include <primitives/transaction.h>
 #include <rpc/server.h>
+#include <rpc/server_util.h>
 #include <rpc/util.h>
 #include <script/descriptor.h>
 #include <streams.h>
@@ -73,67 +76,6 @@ static CUpdatedBlock latestblock GUARDED_BY(cs_blockchange);
 
 extern void TxToJSON(const CTransaction& tx, const uint256 hashBlock, CTxMemPool& mempool, CChainState& active_chainstate, llmq::CChainLocksHandler& clhandler, llmq::CInstantSendManager& isman, UniValue& entry);
 
-NodeContext& EnsureAnyNodeContext(const CoreContext& context)
-{
-    auto* const node_context = GetContext<NodeContext>(context);
-    if (!node_context) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Node context not found");
-    }
-    return *node_context;
-}
-
-CTxMemPool& EnsureMemPool(const NodeContext& node)
-{
-    if (!node.mempool) {
-        throw JSONRPCError(RPC_CLIENT_MEMPOOL_DISABLED, "Mempool disabled or instance not found");
-    }
-    return *node.mempool;
-}
-
-CTxMemPool& EnsureAnyMemPool(const CoreContext& context)
-{
-    return EnsureMemPool(EnsureAnyNodeContext(context));
-}
-
-ChainstateManager& EnsureChainman(const NodeContext& node)
-{
-    if (!node.chainman) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Node chainman not found");
-    }
-    return *node.chainman;
-}
-
-ChainstateManager& EnsureAnyChainman(const CoreContext& context)
-{
-    return EnsureChainman(EnsureAnyNodeContext(context));
-}
-
-CBlockPolicyEstimator& EnsureFeeEstimator(const NodeContext& node)
-{
-    if (!node.fee_estimator) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Fee estimation disabled");
-    }
-    return *node.fee_estimator;
-}
-
-CBlockPolicyEstimator& EnsureAnyFeeEstimator(const CoreContext& context)
-{
-    return EnsureFeeEstimator(EnsureAnyNodeContext(context));
-}
-
-LLMQContext& EnsureLLMQContext(const NodeContext& node)
-{
-    if (!node.llmq_ctx) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Node LLMQ context not found");
-    }
-    return *node.llmq_ctx;
-}
-
-LLMQContext& EnsureAnyLLMQContext(const CoreContext& context)
-{
-    return EnsureLLMQContext(EnsureAnyNodeContext(context));
-}
-
 /* Calculate the difficulty for a given block index.
  */
 double GetDifficulty(const CBlockIndex* blockindex)
@@ -825,6 +767,58 @@ static RPCHelpMan getmempoolentry()
     };
 }
 
+static RPCHelpMan getblockfrompeer()
+{
+    return RPCHelpMan{"getblockfrompeer",
+                "\nAttempt to fetch block from a given peer.\n"
+                "\nWe must have the header for this block, e.g. using submitheader.\n"
+                "\nReturns {} if a block-request was successfully scheduled\n",
+                {
+                    {"blockhash", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The block hash"},
+                    {"nodeid", RPCArg::Type::NUM, RPCArg::Optional::NO, "The node ID (see getpeerinfo for node IDs)"},
+                },
+                RPCResult{RPCResult::Type::OBJ, "", "",
+                {
+                    {RPCResult::Type::STR, "warnings", "any warnings"}
+                }},
+                RPCExamples{
+                    HelpExampleCli("getblockfrompeer", "\"00000000c937983704a73af28acdec37b049d214adbda81d7e2a3dd146f6ed09\" 0")
+                + HelpExampleRpc("getblockfrompeer", "\"00000000c937983704a73af28acdec37b049d214adbda81d7e2a3dd146f6ed09\" 0")
+                },
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
+    const NodeContext& node = EnsureAnyNodeContext(request.context);
+    ChainstateManager& chainman = EnsureChainman(node);
+    PeerManager& peerman = EnsurePeerman(node);
+    CConnman& connman = EnsureConnman(node);
+
+    uint256 hash(ParseHashV(request.params[0], "hash"));
+
+    const NodeId nodeid = static_cast<NodeId>(request.params[1].get_int64());
+
+    // Check that the peer with nodeid exists
+    if (!connman.ForNode(nodeid, [](CNode* node) {return true;})) {
+        throw JSONRPCError(RPC_MISC_ERROR, strprintf("Peer nodeid %d does not exist", nodeid));
+    }
+
+    const CBlockIndex* const index = WITH_LOCK(cs_main, return chainman.m_blockman.LookupBlockIndex(hash););
+
+    if (!index) {
+        throw JSONRPCError(RPC_MISC_ERROR, "Block header missing");
+    }
+
+    UniValue result = UniValue::VOBJ;
+
+    if (index->nStatus & BLOCK_HAVE_DATA) {
+        result.pushKV("warnings", "Block already downloaded");
+    } else if (!peerman.FetchBlock(nodeid, hash, *index)) {
+        throw JSONRPCError(RPC_MISC_ERROR, "Failed to fetch block from peer");
+    }
+    return result;
+},
+    };
+}
+
 static RPCHelpMan getblockhashes()
 {
     return RPCHelpMan{"getblockhashes",
@@ -3058,6 +3052,7 @@ static const CRPCCommand commands[] =
     { "blockchain",         "getbestchainlock",       &getbestchainlock,       {} },
     { "blockchain",         "getblockcount",          &getblockcount,          {} },
     { "blockchain",         "getblock",               &getblock,               {"blockhash","verbosity|verbose"} },
+    { "blockchain",         "getblockfrompeer",       &getblockfrompeer,       {"blockhash", "nodeid"}},
     { "blockchain",         "getblockhashes",         &getblockhashes,         {"high","low"} },
     { "blockchain",         "getblockhash",           &getblockhash,           {"height"} },
     { "blockchain",         "getblockheader",         &getblockheader,         {"blockhash","verbose"} },

src/rpc/blockchain.h

@@ -6,7 +6,6 @@
 #define BITCOIN_RPC_BLOCKCHAIN_H
 
 #include <amount.h>
-#include <context.h>
 #include <core_io.h>
 #include <streams.h>
 #include <sync.h>
@@ -18,12 +17,9 @@ extern RecursiveMutex cs_main;
 
 class CBlock;
 class CBlockIndex;
-class CBlockPolicyEstimator;
 class CChainState;
 class CTxMemPool;
-class ChainstateManager;
 class UniValue;
-struct LLMQContext;
 struct NodeContext;
 namespace llmq {
 class CChainLocksHandler;
@@ -61,16 +57,6 @@ void CalculatePercentilesBySize(CAmount result[NUM_GETBLOCKSTATS_PERCENTILES], s
 void ScriptPubKeyToUniv(const CScript& scriptPubKey, UniValue& out, bool fIncludeHex);
 void TxToUniv(const CTransaction& tx, const uint256& hashBlock, UniValue& entry, bool include_hex = true, const CTxUndo* txundo = nullptr, const CSpentIndexTxInfo* ptxSpentInfo = nullptr);
 
-NodeContext& EnsureAnyNodeContext(const CoreContext& context);
-CTxMemPool& EnsureMemPool(const NodeContext& node);
-CTxMemPool& EnsureAnyMemPool(const CoreContext& context);
-ChainstateManager& EnsureChainman(const NodeContext& node);
-ChainstateManager& EnsureAnyChainman(const CoreContext& context);
-CBlockPolicyEstimator& EnsureFeeEstimator(const NodeContext& node);
-CBlockPolicyEstimator& EnsureAnyFeeEstimator(const CoreContext& context);
-LLMQContext& EnsureLLMQContext(const NodeContext& node);
-LLMQContext& EnsureAnyLLMQContext(const CoreContext& context);
-
 /**
  * Helper to create UTXO snapshots given a chainstate and a file handle.
  * @return a UniValue map containing metadata about the snapshot.

src/rpc/client.cpp

@@ -66,6 +66,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "getbalance", 2, "addlocked" },
     { "getbalance", 3, "include_watchonly" },
     { "getbalance", 4, "avoid_reuse" },
+    { "getblockfrompeer", 1, "nodeid" },
     { "getchaintips", 0, "count" },
     { "getchaintips", 1, "branchlen" },
     { "getblockhash", 0, "height" },

src/rpc/coinjoin.cpp

@@ -7,8 +7,8 @@
 #include <coinjoin/context.h>
 #include <coinjoin/server.h>
 #include <rpc/blockchain.h>
-#include <rpc/net.h>
 #include <rpc/server.h>
+#include <rpc/server_util.h>
 #include <rpc/util.h>
 #include <util/strencodings.h>
 

src/rpc/evo.cpp

@@ -24,6 +24,7 @@
 #include <node/context.h>
 #include <rpc/blockchain.h>
 #include <rpc/server.h>
+#include <rpc/server_util.h>
 #include <rpc/util.h>
 #include <util/moneystr.h>
 #include <util/translation.h>

src/rpc/governance.cpp

@@ -16,8 +16,8 @@
 #include <node/context.h>
 #include <net.h>
 #include <rpc/blockchain.h>
-#include <rpc/net.h>
 #include <rpc/server.h>
+#include <rpc/server_util.h>
 #include <rpc/util.h>
 #include <governance/common.h>
 #include <util/strencodings.h>