Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2019 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             : #include <version.h>
      11             : #include <consensus/consensus.h>
      12             : #include <primitives/transaction.h>
      13             : #include <primitives/block.h>
      14             : 
      15             : /** A "reason" why a transaction was invalid, suitable for determining whether the
      16             :   * provider of the transaction should be banned/ignored/disconnected/etc.
      17             :   */
      18             : enum class TxValidationResult {
      19             :     TX_RESULT_UNSET = 0,     //!< initial value. Tx has not yet been rejected
      20             :     TX_CONSENSUS,            //!< invalid by consensus rules
      21             :     /**
      22             :      * Invalid by a change to consensus rules more recent than SegWit.
      23             :      * Currently unused as there are no such consensus rule changes, and any download
      24             :      * sources realistically need to support SegWit in order to provide useful data,
      25             :      * so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
      26             :      * is uninteresting.
      27             :      */
      28             :     TX_RECENT_CONSENSUS_CHANGE,
      29             :     TX_INPUTS_NOT_STANDARD,   //!< inputs (covered by txid) failed policy rules
      30             :     TX_NOT_STANDARD,          //!< otherwise didn't meet our local policy rules
      31             :     TX_MISSING_INPUTS,        //!< transaction was missing some of its inputs
      32             :     TX_PREMATURE_SPEND,       //!< transaction spends a coinbase too early, or violates locktime/sequence locks
      33             :     /**
      34             :      * Transaction might have a witness prior to SegWit
      35             :      * activation, or witness may have been malleated (which includes
      36             :      * non-standard witnesses).
      37             :      */
      38             :     TX_WITNESS_MUTATED,
      39             :     /**
      40             :      * Transaction is missing a witness.
      41             :      */
      42             :     TX_WITNESS_STRIPPED,
      43             :     /**
      44             :      * Tx already in mempool or conflicts with a tx in the chain
      45             :      * (if it conflicts with another tx in mempool, we use MEMPOOL_POLICY as it failed to reach the RBF threshold)
      46             :      * Currently this is only used if the transaction already exists in the mempool or on chain.
      47             :      */
      48             :     TX_CONFLICT,
      49             :     TX_MEMPOOL_POLICY,        //!< violated mempool's fee/size/descendant/RBF/etc limits
      50             : };
      51             : 
      52             : /** A "reason" why a block was invalid, suitable for determining whether the
      53             :   * provider of the block should be banned/ignored/disconnected/etc.
      54             :   * These are much more granular than the rejection codes, which may be more
      55             :   * useful for some other use-cases.
      56             :   */
      57             : enum class BlockValidationResult {
      58             :     BLOCK_RESULT_UNSET = 0,  //!< initial value. Block has not yet been rejected
      59             :     BLOCK_CONSENSUS,         //!< invalid by consensus rules (excluding any below reasons)
      60             :     /**
      61             :      * Invalid by a change to consensus rules more recent than SegWit.
      62             :      * Currently unused as there are no such consensus rule changes, and any download
      63             :      * sources realistically need to support SegWit in order to provide useful data,
      64             :      * so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
      65             :      * is uninteresting.
      66             :      */
      67             :     BLOCK_RECENT_CONSENSUS_CHANGE,
      68             :     BLOCK_CACHED_INVALID,    //!< this block was cached as being invalid and we didn't store the reason why
      69             :     BLOCK_INVALID_HEADER,    //!< invalid proof of work or time too old
      70             :     BLOCK_MUTATED,           //!< the block's data didn't match the data committed to by the PoW
      71             :     BLOCK_MISSING_PREV,      //!< We don't have the previous block the checked one is built on
      72             :     BLOCK_INVALID_PREV,      //!< A block this one builds on is invalid
      73             :     BLOCK_TIME_FUTURE,       //!< block timestamp was > 2 hours in the future (or our clock is bad)
      74             :     BLOCK_CHECKPOINT,        //!< the block failed to meet one of our checkpoints
      75             : };
      76             : 
      77             : 
      78             : 
      79             : /** Template for capturing information about block/transaction validation. This is instantiated
      80             :  *  by TxValidationState and BlockValidationState for validation information on transactions
      81             :  *  and blocks respectively. */
      82             : template <typename Result>
      83    11520597 : class ValidationState
      84             : {
      85             : private:
      86             :     enum class ModeState {
      87             :         M_VALID,   //!< everything ok
      88             :         M_INVALID, //!< network rule violation (DoS value may be set)
      89             :         M_ERROR,   //!< run-time error
      90     5760117 :     } m_mode{ModeState::M_VALID};
      91     5760117 :     Result m_result{};
      92             :     std::string m_reject_reason;
      93             :     std::string m_debug_message;
      94             : 
      95             : public:
      96       68516 :     bool Invalid(Result result,
      97             :                  const std::string& reject_reason = "",
      98             :                  const std::string& debug_message = "")
      99             :     {
     100       68516 :         m_result = result;
     101       68516 :         m_reject_reason = reject_reason;
     102       68516 :         m_debug_message = debug_message;
     103       68516 :         if (m_mode != ModeState::M_ERROR) m_mode = ModeState::M_INVALID;
     104       68516 :         return false;
     105             :     }
     106           1 :     bool Error(const std::string& reject_reason)
     107             :     {
     108           1 :         if (m_mode == ModeState::M_VALID)
     109           1 :             m_reject_reason = reject_reason;
     110           1 :         m_mode = ModeState::M_ERROR;
     111           1 :         return false;
     112             :     }
     113      125422 :     bool IsValid() const { return m_mode == ModeState::M_VALID; }
     114       53272 :     bool IsInvalid() const { return m_mode == ModeState::M_INVALID; }
     115        1465 :     bool IsError() const { return m_mode == ModeState::M_ERROR; }
     116        2412 :     Result GetResult() const { return m_result; }
     117         336 :     std::string GetRejectReason() const { return m_reject_reason; }
     118         267 :     std::string GetDebugMessage() const { return m_debug_message; }
     119       61043 :     std::string ToString() const
     120             :     {
     121       61043 :         if (IsValid()) {
     122       59251 :             return "Valid";
     123             :         }
     124             : 
     125        1792 :         if (!m_debug_message.empty()) {
     126         661 :             return m_reject_reason + ", " + m_debug_message;
     127             :         }
     128             : 
     129        1131 :         return m_reject_reason;
     130       61043 :     }
     131             : };
     132             : 
     133    22288704 : class TxValidationState : public ValidationState<TxValidationResult> {};
     134      752126 : class BlockValidationState : public ValidationState<BlockValidationResult> {};
     135             : 
     136             : // These implement the weight = (stripped_size * 4) + witness_size formula,
     137             : // using only serialization with and without witness data. As witness_size
     138             : // is equal to total_size - stripped_size, this formula is identical to:
     139             : // weight = (stripped_size * 3) + total_size.
     140      110105 : static inline int64_t GetTransactionWeight(const CTransaction& tx)
     141             : {
     142      110105 :     return ::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(tx, PROTOCOL_VERSION);
     143             : }
     144       90875 : static inline int64_t GetBlockWeight(const CBlock& block)
     145             : {
     146       90875 :     return ::GetSerializeSize(block, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(block, PROTOCOL_VERSION);
     147             : }
     148      228428 : static inline int64_t GetTransactionInputWeight(const CTxIn& txin)
     149             : {
     150             :     // scriptWitness size is added here because witnesses and txins are split up in segwit serialization.
     151      228428 :     return ::GetSerializeSize(txin, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(txin, PROTOCOL_VERSION) + ::GetSerializeSize(txin.scriptWitness.stack, PROTOCOL_VERSION);
     152             : }
     153             : 
     154             : #endif // BITCOIN_CONSENSUS_VALIDATION_H