RCLConsensus.h

//------------------------------------------------------------------------------
/*
    This file is part of rippled: https://github.com/ripple/rippled
    Copyright (c) 2012, 2013 Ripple Labs Inc.
 
    Permission to use, copy, modify, and/or distribute this software for any
    purpose  with  or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.
 
    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
 
#ifndef RIPPLE_APP_CONSENSUS_RCLCONSENSUS_H_INCLUDED
#define RIPPLE_APP_CONSENSUS_RCLCONSENSUS_H_INCLUDED
 
#include <ripple/app/consensus/RCLCensorshipDetector.h>
#include <ripple/app/consensus/RCLCxLedger.h>
#include <ripple/app/consensus/RCLCxPeerPos.h>
#include <ripple/app/consensus/RCLCxTx.h>
#include <ripple/app/misc/FeeVote.h>
#include <ripple/app/misc/NegativeUNLVote.h>
#include <ripple/basics/CountedObject.h>
#include <ripple/basics/Log.h>
#include <ripple/basics/chrono.h>
#include <ripple/beast/utility/Journal.h>
#include <ripple/consensus/Consensus.h>
#include <ripple/core/JobQueue.h>
#include <ripple/overlay/Message.h>
#include <ripple/protocol/RippleLedgerHash.h>
#include <ripple/protocol/STValidation.h>
#include <ripple/shamap/SHAMap.h>
#include <atomic>
#include <chrono>
#include <mutex>
#include <optional>
#include <set>
 
namespace ripple {
 
class InboundTransactions;
class LocalTxs;
class LedgerMaster;
class ValidatorKeys;
 
class RCLConsensus
{
    constexpr static unsigned int censorshipWarnInternal = 15;
 
    // Implements the Adaptor template interface required by Consensus.
    class Adaptor
    {
        Application& app_;
        std::unique_ptr<FeeVote> feeVote_;
        LedgerMaster& ledgerMaster_;
 
        LocalTxs& localTxs_;
        InboundTransactions& inboundTransactions_;
        beast::Journal const j_;
 
        // If the server is validating, the necessary keying information:
        ValidatorKeys const& validatorKeys_;
 
        // A randomly selected non-zero value used to tag our validations
        std::uint64_t const valCookie_;
 
        // Ledger we most recently needed to acquire
        LedgerHash acquiringLedger_;
        ConsensusParms parms_;
 
        // The timestamp of the last validation we used
        NetClock::time_point lastValidationTime_;
 
        // These members are queried via public accesors and are atomic for
        // thread safety.
        std::atomic<std::size_t> prevProposers_{0};
        std::atomic<std::chrono::milliseconds> prevRoundTime_{
            std::chrono::milliseconds{0}};
        std::atomic<ConsensusMode> mode_{ConsensusMode::observing};
 
        RCLCensorshipDetector<TxID, LedgerIndex> censorshipDetector_;
        NegativeUNLVote nUnlVote_;
 
        // Since Consensus does not provide intrinsic thread-safety, this mutex
        // needs to guard all calls to consensus_. One reason it is recursive
        // is because logic in phaseEstablish() around buildAndValidate()
        // needs to lock and unlock to protect Consensus data members.
        mutable std::recursive_mutex mutex_;
        std::optional<std::chrono::milliseconds> validationDelay_;
        std::optional<std::chrono::milliseconds> timerDelay_;
        std::atomic<bool> validating_{false};
 
    public:
        using Ledger_t = RCLCxLedger;
        using NodeID_t = NodeID;
        using NodeKey_t = PublicKey;
        using TxSet_t = RCLTxSet;
        using CanonicalTxSet_t = CanonicalTXSet;
        using PeerPosition_t = RCLCxPeerPos;
 
        using Result = ConsensusResult<Adaptor>;
        using clock_type = Stopwatch;
 
        Adaptor(
            Application& app,
            std::unique_ptr<FeeVote>&& feeVote,
            LedgerMaster& ledgerMaster,
            LocalTxs& localTxs,
            InboundTransactions& inboundTransactions,
            ValidatorKeys const& validatorKeys,
            beast::Journal journal);
 
        bool
        validating() const
        {
            return validating_;
        }
 
        std::size_t
        prevProposers() const
        {
            return prevProposers_;
        }
 
        std::chrono::milliseconds
        prevRoundTime() const
        {
            return prevRoundTime_;
        }
 
        ConsensusMode
        mode() const
        {
            return mode_;
        }
 
        bool
        preStartRound(
            RCLCxLedger const& prevLedger,
            hash_set<NodeID> const& nowTrusted);
 
        bool
        haveValidated() const;
 
        LedgerIndex
        getValidLedgerIndex() const;
 
        std::pair<std::size_t, hash_set<NodeKey_t>>
        getQuorumKeys() const;
 
        std::size_t
        quorum() const;
 
        std::size_t
        laggards(Ledger_t::Seq const seq, hash_set<NodeKey_t>& trustedKeys)
            const;
 
        bool
        validator() const;
 
        void
        updateOperatingMode(std::size_t const positions) const;
 
        ConsensusParms const&
        parms() const
        {
            return parms_;
        }
 
        std::recursive_mutex&
        peekMutex() const
        {
            return mutex_;
        }
 
        LedgerMaster&
        getLedgerMaster() const
        {
            return ledgerMaster_;
        }
 
        void
        clearValidating()
        {
            validating_ = false;
        }
 
        bool
        retryAccept(
            Ledger_t const& newLedger,
            std::optional<std::chrono::time_point<std::chrono::steady_clock>>&
                start) const;
 
        std::optional<std::chrono::milliseconds>
        getValidationDelay() const
        {
            return validationDelay_;
        }
 
        void
        setValidationDelay(
            std::optional<std::chrono::milliseconds> vd = std::nullopt)
        {
            validationDelay_ = vd;
        }
 
        std::optional<std::chrono::milliseconds>
        getTimerDelay() const
        {
            return timerDelay_;
        }
 
        void
        setTimerDelay(
            std::optional<std::chrono::milliseconds> td = std::nullopt)
        {
            timerDelay_ = td;
        }
 
    private:
        //---------------------------------------------------------------------
        // The following members implement the generic Consensus requirements
        // and are marked private to indicate ONLY Consensus<Adaptor> will call
        // them (via friendship). Since they are called only from
        // Consensus<Adaptor> methods and since RCLConsensus::consensus_ should
        // only be accessed under lock, these will only be called under lock.
        //
        // In general, the idea is that there is only ONE thread that is running
        // consensus code at anytime. The only special case is the dispatched
        // onAccept call, which does not take a lock and relies on Consensus not
        // changing state until a future call to startRound.
        friend class Consensus<Adaptor>;
 
        std::optional<RCLCxLedger>
        acquireLedger(LedgerHash const& hash);
 
        void
        share(RCLCxPeerPos const& peerPos);
 
        void
        share(RCLCxTx const& tx);
 
        std::optional<RCLTxSet>
        acquireTxSet(RCLTxSet::ID const& setId);
 
        bool
        hasOpenTransactions() const;
 
        std::size_t
        proposersValidated(LedgerHash const& h) const;
 
        std::size_t
        proposersFinished(RCLCxLedger const& ledger, LedgerHash const& h) const;
 
        void
        propose(RCLCxPeerPos::Proposal const& proposal);
 
        void
        share(RCLTxSet const& txns);
 
        uint256
        getPrevLedger(
            uint256 ledgerID,
            RCLCxLedger const& ledger,
            ConsensusMode mode);
 
        void
        onModeChange(ConsensusMode before, ConsensusMode after);
 
        Result
        onClose(
            RCLCxLedger const& ledger,
            NetClock::time_point const& closeTime,
            ConsensusMode mode,
            clock_type& clock);
 
        void
        onAccept(
            Result const& result,
            ConsensusCloseTimes const& rawCloseTimes,
            ConsensusMode const& mode,
            Json::Value&& consensusJson,
            std::pair<CanonicalTxSet_t, Ledger_t>&& txsBuilt);
 
        void
        onForceAccept(
            Result const& result,
            RCLCxLedger const& prevLedger,
            NetClock::duration const& closeResolution,
            ConsensusCloseTimes const& rawCloseTimes,
            ConsensusMode const& mode,
            Json::Value&& consensusJson);
 
        void
        notify(
            protocol::NodeEvent ne,
            RCLCxLedger const& ledger,
            bool haveCorrectLCL);
 
        std::pair<CanonicalTxSet_t, Ledger_t>
        buildAndValidate(
            Result const& result,
            Ledger_t const& prevLedger,
            NetClock::duration const& closeResolution,
            ConsensusMode const& mode,
            Json::Value&& consensusJson);
 
        void
        prepareOpenLedger(
            std::pair<CanonicalTxSet_t, Ledger_t>&& txsBuilt,
            Result const& result,
            ConsensusCloseTimes const& rawCloseTimes,
            ConsensusMode const& mode);
 
        RCLCxLedger
        buildLCL(
            RCLCxLedger const& previousLedger,
            CanonicalTXSet& retriableTxs,
            NetClock::time_point closeTime,
            bool closeTimeCorrect,
            NetClock::duration closeResolution,
            std::chrono::milliseconds roundTime,
            std::set<TxID>& failedTxs);
 
        void
        validate(
            RCLCxLedger const& ledger,
            RCLTxSet const& txns,
            bool proposing);
    };
 
public:
    RCLConsensus(
        Application& app,
        std::unique_ptr<FeeVote>&& feeVote,
        LedgerMaster& ledgerMaster,
        LocalTxs& localTxs,
        InboundTransactions& inboundTransactions,
        Consensus<Adaptor>::clock_type& clock,
        ValidatorKeys const& validatorKeys,
        beast::Journal journal);
 
    RCLConsensus(RCLConsensus const&) = delete;
 
    RCLConsensus&
    operator=(RCLConsensus const&) = delete;
 
    bool
    validating() const
    {
        return adaptor_.validating();
    }
 
    std::size_t
    prevProposers() const
    {
        return adaptor_.prevProposers();
    }
 
    std::chrono::milliseconds
    prevRoundTime() const
    {
        return adaptor_.prevRoundTime();
    }
 
    ConsensusMode
    mode() const
    {
        return adaptor_.mode();
    }
 
    ConsensusPhase
    phase() const
    {
        return consensus_.phase();
    }
 
    Json::Value
    getJson(bool full) const;
 
    void
    startRound(
        NetClock::time_point const& now,
        RCLCxLedger::ID const& prevLgrId,
        RCLCxLedger const& prevLgr,
        hash_set<NodeID> const& nowUntrusted,
        hash_set<NodeID> const& nowTrusted);
 
    void
    timerEntry(NetClock::time_point const& now);
 
    void
    gotTxSet(NetClock::time_point const& now, RCLTxSet const& txSet);
 
    // @see Consensus::prevLedgerID
    RCLCxLedger::ID
    prevLedgerID() const
    {
        std::lock_guard _{adaptor_.peekMutex()};
        return consensus_.prevLedgerID();
    }
 
    void
    simulate(
        NetClock::time_point const& now,
        std::optional<std::chrono::milliseconds> consensusDelay);
 
    bool
    peerProposal(
        NetClock::time_point const& now,
        RCLCxPeerPos const& newProposal);
 
    ConsensusParms const&
    parms() const
    {
        return adaptor_.parms();
    }
 
    std::optional<std::chrono::milliseconds>
    getTimerDelay() const
    {
        return adaptor_.getTimerDelay();
    }
 
    void
    setTimerDelay(std::optional<std::chrono::milliseconds> td = std::nullopt)
    {
        adaptor_.setTimerDelay(td);
    }
 
private:
    Adaptor adaptor_;
    Consensus<Adaptor> consensus_;
    beast::Journal const j_;
};
}  // namespace ripple
 
#endif