Line data    Source code

       1             : // Copyright (c) 2018-2025 The Dash Core developers
       2             : // Distributed under the MIT/X11 software license, see the accompanying
       3             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4             : 
       5             : #ifndef BITCOIN_LLMQ_DKGSESSIONHANDLER_H
       6             : #define BITCOIN_LLMQ_DKGSESSIONHANDLER_H
       7             : 
       8             : #include <net.h> // for NodeId
       9             : #include <sync.h>
      10             : 
      11             : #include <list>
      12             : #include <map>
      13             : #include <memory>
      14             : #include <optional>
      15             : #include <string_view>
      16             : #include <vector>
      17             : 
      18             : class CDataStream;
      19             : class CBlockIndex;
      20             : class uint256;
      21             : 
      22             : namespace Consensus {
      23             : struct LLMQParams;
      24             : } // namespace Consensus
      25             : 
      26             : namespace llmq
      27             : {
      28             : class CDKGContribution;
      29             : class CDKGComplaint;
      30             : class CDKGJustification;
      31             : class CDKGPrematureCommitment;
      32             : class CDKGSessionManager;
      33             : 
      34             : enum class QuorumPhase {
      35             :     Initialized = 1,
      36             :     Contribute,
      37             :     Complain,
      38             :     Justify,
      39             :     Commit,
      40             :     Finalize,
      41             :     Idle,
      42             : };
      43             : 
      44             : /**
      45             :  * Acts as a FIFO queue for incoming DKG messages. The reason we need this is that deserialization of these messages
      46             :  * is too slow to be processed in the main message handler thread. So, instead of processing them directly from the
      47             :  * main handler thread, we push them into a CDKGPendingMessages object and later pop+deserialize them in the DKG phase
      48             :  * handler thread.
      49             :  *
      50             :  * Each message type has it's own instance of this class.
      51             :  */
      52             : class CDKGPendingMessages
      53             : {
      54             : public:
      55             :     using BinaryMessage = std::pair<NodeId, std::shared_ptr<CDataStream>>;
      56             : 
      57             : private:
      58             :     const size_t maxMessagesPerNode;
      59             :     mutable Mutex cs_messages;
      60             :     std::list<BinaryMessage> pendingMessages GUARDED_BY(cs_messages);
      61             :     std::map<NodeId, size_t> messagesPerNode GUARDED_BY(cs_messages);
      62             :     Uint256HashSet seenMessages GUARDED_BY(cs_messages);
      63             : 
      64             : public:
      65           0 :     explicit CDKGPendingMessages(size_t _maxMessagesPerNode) :
      66           0 :         maxMessagesPerNode(_maxMessagesPerNode) {};
      67             : 
      68             :     /**
      69             :      * Enqueue a serialized DKG message under @p from with content hash @p hash.
      70             :      * Caller is responsible for hashing the payload and (for real peers)
      71             :      * routing the erase-request to PeerManager. Drops the message silently on
      72             :      * per-node capacity overflow or duplicate hash.
      73             :      */
      74             :     void PushPendingMessage(NodeId from, std::shared_ptr<CDataStream> pm, const uint256& hash)
      75             :         EXCLUSIVE_LOCKS_REQUIRED(!cs_messages);
      76             : 
      77             :     std::list<BinaryMessage> PopPendingMessages(size_t maxCount) EXCLUSIVE_LOCKS_REQUIRED(!cs_messages);
      78             :     bool HasSeen(const uint256& hash) const EXCLUSIVE_LOCKS_REQUIRED(!cs_messages);
      79             :     void Clear() EXCLUSIVE_LOCKS_REQUIRED(!cs_messages);
      80             : 
      81             :     // Might return nullptr messages, which indicates that deserialization failed for some reason
      82             :     template <typename Message>
      83           0 :     std::vector<std::pair<NodeId, std::shared_ptr<Message>>> PopAndDeserializeMessages(size_t maxCount)
      84             :         EXCLUSIVE_LOCKS_REQUIRED(!cs_messages)
      85             :     {
      86           0 :         auto binaryMessages = PopPendingMessages(maxCount);
      87           0 :         if (binaryMessages.empty()) {
      88           0 :             return {};
      89             :         }
      90             : 
      91           0 :         std::vector<std::pair<NodeId, std::shared_ptr<Message>>> ret;
      92           0 :         ret.reserve(binaryMessages.size());
      93           0 :         for (const auto& bm : binaryMessages) {
      94           0 :             auto msg = std::make_shared<Message>();
      95             :             try {
      96           0 :                 *bm.second >> *msg;
      97           0 :             } catch (...) {
      98           0 :                 msg = nullptr;
      99           0 :             }
     100           0 :             ret.emplace_back(std::make_pair(bm.first, std::move(msg)));
     101           0 :         }
     102             : 
     103           0 :         return ret;
     104           0 :     }
     105             : };
     106             : 
     107             : /**
     108             :  * Handles multiple sequential sessions of one specific LLMQ type. There is one instance of this class per LLMQ type.
     109             :  */
     110             : class CDKGSessionHandler
     111             : {
     112             : public:
     113             :     const Consensus::LLMQParams& params;
     114             : 
     115             :     // Do not guard these, they protect their internals themselves
     116             :     CDKGPendingMessages pendingContributions;
     117             :     CDKGPendingMessages pendingComplaints;
     118             :     CDKGPendingMessages pendingJustifications;
     119             :     CDKGPendingMessages pendingPrematureCommitments;
     120             : 
     121             : public:
     122             :     explicit CDKGSessionHandler(const Consensus::LLMQParams& _params);
     123             :     virtual ~CDKGSessionHandler();
     124             : 
     125             :     void ClearPendingMessages();
     126             : 
     127             : public:
     128           0 :     virtual bool GetContribution(const uint256& hash, CDKGContribution& ret) const { return false; }
     129           0 :     virtual bool GetComplaint(const uint256& hash, CDKGComplaint& ret) const { return false; }
     130           0 :     virtual bool GetJustification(const uint256& hash, CDKGJustification& ret) const { return false; }
     131           0 :     virtual bool GetPrematureCommitment(const uint256& hash, CDKGPrematureCommitment& ret) const { return false; }
     132           0 :     virtual QuorumPhase GetPhase() const { return QuorumPhase::Idle; }
     133           0 :     virtual void UpdatedBlockTip(const CBlockIndex* pindexNew) {}
     134             : };
     135             : } // namespace llmq
     136             : 
     137             : #endif // BITCOIN_LLMQ_DKGSESSIONHANDLER_H