Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2021 The Bitcoin Core developers
       3             : // Distributed under the MIT software license, see the accompanying
       4             : // file COPYING or http://www.opensource.org/licenses/mit-license.php.
       5             : 
       6             : #ifndef BITCOIN_CONSENSUS_VALIDATION_H
       7             : #define BITCOIN_CONSENSUS_VALIDATION_H
       8             : 
       9             : #include <string>
      10             : 
      11             : /** A "reason" why a transaction was invalid, suitable for determining whether the
      12             :   * provider of the transaction should be banned/ignored/disconnected/etc.
      13             :   */
      14             : enum class TxValidationResult {
      15             :     TX_RESULT_UNSET = 0,     //!< initial value. Tx has not yet been rejected
      16             :     TX_CONSENSUS,            //!< invalid by consensus rules
      17             :     /**
      18             :      * Invalid by a change to consensus rules more recent than some major deployment.
      19             :      */
      20             :     // Only loose txn:
      21             :     TX_RECENT_CONSENSUS_CHANGE,
      22             :     TX_INPUTS_NOT_STANDARD,   //!< inputs (covered by txid) failed policy rules
      23             :     TX_NOT_STANDARD,          //!< otherwise didn't meet our local policy rules
      24             :     TX_MISSING_INPUTS,        //!< transaction was missing some of its inputs
      25             :     TX_PREMATURE_SPEND,       //!< transaction spends a coinbase too early, or violates locktime/sequence locks
      26             :     TX_BAD_SPECIAL,           //!< special transaction violates some rules that are not enough for insta-ban
      27             :     /**
      28             :      * Tx already in mempool or conflicts with a tx in the chain
      29             :      * Currently this is only used if the transaction already exists in the mempool or on chain.
      30             :      */
      31             :     TX_CONFLICT,
      32             :     TX_CONFLICT_LOCK,         //!< conflicts with InstantSend lock
      33             :     TX_MEMPOOL_POLICY,        //!< violated mempool's fee/size/descendant/etc limits
      34             :     TX_NO_MEMPOOL,            //!< this node does not have a mempool so can't validate the transaction
      35             : };
      36             : 
      37             : /** A "reason" why a block was invalid, suitable for determining whether the
      38             :   * provider of the block should be banned/ignored/disconnected/etc.
      39             :   * These are much more granular than the rejection codes, which may be more
      40             :   * useful for some other use-cases.
      41             :   */
      42             : enum class BlockValidationResult {
      43             :     BLOCK_RESULT_UNSET = 0,  //!< initial value. Block has not yet been rejected
      44             :     BLOCK_CONSENSUS,         //!< invalid by consensus rules (excluding any below reasons)
      45             :     /**
      46             :      * Invalid by a change to consensus rules more recent than SegWit.
      47             :      * Currently unused as there are no such consensus rule changes, and any download
      48             :      * sources realistically need to support SegWit in order to provide useful data,
      49             :      * so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
      50             :      * is uninteresting.
      51             :      */
      52             :     BLOCK_RECENT_CONSENSUS_CHANGE,
      53             :     BLOCK_CACHED_INVALID,    //!< this block was cached as being invalid and we didn't store the reason why
      54             :     BLOCK_INVALID_HEADER,    //!< invalid proof of work or time too old
      55             :     BLOCK_MUTATED,           //!< the block's data didn't match the data committed to by the PoW
      56             :     BLOCK_MISSING_PREV,      //!< We don't have the previous block the checked one is built on
      57             :     BLOCK_INVALID_PREV,      //!< A block this one builds on is invalid
      58             :     BLOCK_TIME_FUTURE,       //!< block timestamp was > 2 hours in the future (or our clock is bad)
      59             :     BLOCK_CHECKPOINT,        //!< the block failed to meet one of our checkpoints
      60             :     BLOCK_CHAINLOCK,         //!< the block conflicts with the ChainLock
      61             : };
      62             : 
      63             : 
      64             : 
      65             : /** Template for capturing information about block/transaction validation. This is instantiated
      66             :  *  by TxValidationState and BlockValidationState for validation information on transactions
      67             :  *  and blocks respectively. */
      68             : template <typename Result>
      69      540380 : class ValidationState
      70             : {
      71             : private:
      72             :     enum class ModeState {
      73             :         M_VALID,   //!< everything ok
      74             :         M_INVALID, //!< network rule violation (DoS value may be set)
      75             :         M_ERROR,   //!< run-time error
      76      540302 :     } m_mode{ModeState::M_VALID};
      77      540302 :     Result m_result{};
      78             :     std::string m_reject_reason;
      79             :     std::string m_debug_message;
      80             : 
      81             : public:
      82       26494 :     bool Invalid(Result result,
      83             :                  const std::string& reject_reason = "",
      84             :                  const std::string& debug_message = "")
      85             :     {
      86       26494 :         m_result = result;
      87       26494 :         m_reject_reason = reject_reason;
      88       26494 :         m_debug_message = debug_message;
      89       26494 :         if (m_mode != ModeState::M_ERROR) m_mode = ModeState::M_INVALID;
      90       26494 :         return false;
      91             :     }
      92           0 :     bool Error(const std::string& reject_reason)
      93             :     {
      94           0 :         if (m_mode == ModeState::M_VALID)
      95           0 :             m_reject_reason = reject_reason;
      96           0 :         m_mode = ModeState::M_ERROR;
      97           0 :         return false;
      98             :     }
      99       54617 :     bool IsValid() const { return m_mode == ModeState::M_VALID; }
     100          91 :     bool IsInvalid() const { return m_mode == ModeState::M_INVALID; }
     101           0 :     bool IsError() const { return m_mode == ModeState::M_ERROR; }
     102          37 :     Result GetResult() const { return m_result; }
     103          76 :     std::string GetRejectReason() const { return m_reject_reason; }
     104           6 :     std::string GetDebugMessage() const { return m_debug_message; }
     105       29489 :     std::string ToString() const
     106             :     {
     107       29489 :         if (IsValid()) {
     108       29119 :             return "Valid";
     109             :         }
     110             : 
     111         370 :         if (!m_debug_message.empty()) {
     112          13 :             return m_reject_reason + ", " + m_debug_message;
     113             :         }
     114             : 
     115         357 :         return m_reject_reason;
     116       29489 :     }
     117             : };
     118             : 
     119             : class TxValidationState : public ValidationState<TxValidationResult> {};
     120             : class BlockValidationState : public ValidationState<BlockValidationResult> {};
     121             : 
     122             : #endif // BITCOIN_CONSENSUS_VALIDATION_H