Line data    Source code

       1             : // Copyright (c) 2021-2022 The Bitcoin Core developers
       2             : // Distributed under the MIT software license, see the accompanying
       3             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       4             : 
       5             : #ifndef BITCOIN_TXORPHANAGE_H
       6             : #define BITCOIN_TXORPHANAGE_H
       7             : 
       8             : #include <net.h>
       9             : #include <primitives/block.h>
      10             : #include <primitives/transaction.h>
      11             : #include <sync.h>
      12             : 
      13             : #include <map>
      14             : #include <set>
      15             : 
      16             : /** A class to track orphan transactions (failed on TX_MISSING_INPUTS)
      17             :  * Since we cannot distinguish orphans from bad transactions with
      18             :  * non-existent inputs, we heavily limit the number of orphans
      19             :  * we keep and the duration we keep them for.
      20             :  */
      21             : class TxOrphanage {
      22             : public:
      23             :     /** Add a new orphan transaction */
      24             :     bool AddTx(const CTransactionRef& tx, NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      25             : 
      26             :     /** Check if we already have an orphan transaction (by txid or wtxid) */
      27             :     bool HaveTx(const GenTxid& gtxid) const EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      28             : 
      29             :     /** Extract a transaction from a peer's work set
      30             :      *  Returns nullptr if there are no transactions to work on.
      31             :      *  Otherwise returns the transaction reference, and removes
      32             :      *  it from the work set.
      33             :      */
      34             :     CTransactionRef GetTxToReconsider(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      35             : 
      36             :     /** Erase an orphan by txid */
      37             :     int EraseTx(const uint256& txid) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      38             : 
      39             :     /** Erase all orphans announced by a peer (eg, after that peer disconnects) */
      40             :     void EraseForPeer(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      41             : 
      42             :     /** Erase all orphans included in or invalidated by a new block */
      43             :     void EraseForBlock(const CBlock& block) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      44             : 
      45             :     /** Limit the orphanage to the given maximum */
      46             :     void LimitOrphans(unsigned int max_orphans) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);
      47             : 
      48             :     /** Add any orphans that list a particular tx as a parent into the from peer's work set */
      49             :     void AddChildrenToWorkSet(const CTransaction& tx) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);;
      50             : 
      51             :     /** Does this peer have any work to do? */
      52             :     bool HaveTxToReconsider(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(!m_mutex);;
      53             : 
      54             :     /** Return how many entries exist in the orphange */
      55           0 :     size_t Size() EXCLUSIVE_LOCKS_REQUIRED(!m_mutex)
      56             :     {
      57           0 :         LOCK(m_mutex);
      58           0 :         return m_orphans.size();
      59           0 :     }
      60             : 
      61             : protected:
      62             :     /** Guards orphan transactions */
      63             :     mutable Mutex m_mutex;
      64             : 
      65             :     struct OrphanTx {
      66             :         CTransactionRef tx;
      67             :         NodeId fromPeer;
      68             :         int64_t nTimeExpire;
      69             :         size_t list_pos;
      70             :     };
      71             : 
      72             :     /** Map from txid to orphan transaction record. Limited by
      73             :      *  -maxorphantx/DEFAULT_MAX_ORPHAN_TRANSACTIONS */
      74             :     std::map<uint256, OrphanTx> m_orphans GUARDED_BY(m_mutex);
      75             : 
      76             :     /** Which peer provided the orphans that need to be reconsidered */
      77             :     std::map<NodeId, std::set<uint256>> m_peer_work_set GUARDED_BY(m_mutex);
      78             : 
      79             :     using OrphanMap = decltype(m_orphans);
      80             : 
      81             :     struct IteratorComparator
      82             :     {
      83             :         template<typename I>
      84           0 :         bool operator()(const I& a, const I& b) const
      85             :         {
      86           0 :             return &(*a) < &(*b);
      87             :         }
      88             :     };
      89             : 
      90             :     /** Index from the parents' COutPoint into the m_orphans. Used
      91             :      *  to remove orphan transactions from the m_orphans */
      92             :     std::map<COutPoint, std::set<OrphanMap::iterator, IteratorComparator>> m_outpoint_to_orphan_it GUARDED_BY(m_mutex);
      93             : 
      94             :     /** Orphan transactions in vector for quick random eviction */
      95             :     std::vector<OrphanMap::iterator> m_orphan_list GUARDED_BY(m_mutex);
      96             : 
      97             :     /** Index from wtxid into the m_orphans to lookup orphan
      98             :      *  transactions using their witness ids. */
      99             :     std::map<uint256, OrphanMap::iterator> m_wtxid_to_orphan_it GUARDED_BY(m_mutex);
     100             : 
     101             :     /** Erase an orphan by txid */
     102             :     int EraseTxNoLock(const uint256& txid) EXCLUSIVE_LOCKS_REQUIRED(m_mutex);
     103             : };
     104             : 
     105             : #endif // BITCOIN_TXORPHANAGE_H