Branch data Line data Source code
1 : : // Copyright (c) 2009-2010 Satoshi Nakamoto
2 : : // Copyright (c) 2009-2022 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 <consensus/consensus.h>
11 : : #include <primitives/transaction.h>
12 : : #include <primitives/block.h>
13 : :
14 : : /** Index marker for when no witness commitment is present in a coinbase transaction. */
15 : : static constexpr int NO_WITNESS_COMMITMENT{-1};
16 : :
17 : : /** Minimum size of a witness commitment structure. Defined in BIP 141. **/
18 : : static constexpr size_t MINIMUM_WITNESS_COMMITMENT{38};
19 : :
20 : : /** A "reason" why a transaction was invalid, suitable for determining whether the
21 : : * provider of the transaction should be banned/ignored/disconnected/etc.
22 : : */
23 : : enum class TxValidationResult {
24 : : TX_RESULT_UNSET = 0, //!< initial value. Tx has not yet been rejected
25 : : TX_CONSENSUS, //!< invalid by consensus rules
26 : : /**
27 : : * Invalid by a change to consensus rules more recent than SegWit.
28 : : * Currently unused as there are no such consensus rule changes, and any download
29 : : * sources realistically need to support SegWit in order to provide useful data,
30 : : * so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
31 : : * is uninteresting.
32 : : */
33 : : TX_RECENT_CONSENSUS_CHANGE,
34 : : TX_INPUTS_NOT_STANDARD, //!< inputs (covered by txid) failed policy rules
35 : : TX_NOT_STANDARD, //!< otherwise didn't meet our local policy rules
36 : : TX_MISSING_INPUTS, //!< transaction was missing some of its inputs
37 : : TX_PREMATURE_SPEND, //!< transaction spends a coinbase too early, or violates locktime/sequence locks
38 : : /**
39 : : * Transaction might have a witness prior to SegWit
40 : : * activation, or witness may have been malleated (which includes
41 : : * non-standard witnesses).
42 : : */
43 : : TX_WITNESS_MUTATED,
44 : : /**
45 : : * Transaction is missing a witness.
46 : : */
47 : : TX_WITNESS_STRIPPED,
48 : : /**
49 : : * Tx already in mempool or conflicts with a tx in the chain
50 : : * (if it conflicts with another tx in mempool, we use MEMPOOL_POLICY as it failed to reach the RBF threshold)
51 : : * Currently this is only used if the transaction already exists in the mempool or on chain.
52 : : */
53 : : TX_CONFLICT,
54 : : TX_MEMPOOL_POLICY, //!< violated mempool's fee/size/descendant/RBF/etc limits
55 : : TX_NO_MEMPOOL, //!< this node does not have a mempool so can't validate the transaction
56 : : TX_RECONSIDERABLE, //!< fails some policy, but might be acceptable if submitted in a (different) package
57 : : TX_UNKNOWN, //!< transaction was not validated because package failed
58 : : };
59 : :
60 : : /** A "reason" why a block was invalid, suitable for determining whether the
61 : : * provider of the block should be banned/ignored/disconnected/etc.
62 : : * These are much more granular than the rejection codes, which may be more
63 : : * useful for some other use-cases.
64 : : */
65 : : enum class BlockValidationResult {
66 : : BLOCK_RESULT_UNSET = 0, //!< initial value. Block has not yet been rejected
67 : : BLOCK_CONSENSUS, //!< invalid by consensus rules (excluding any below reasons)
68 : : /**
69 : : * Invalid by a change to consensus rules more recent than SegWit.
70 : : * Currently unused as there are no such consensus rule changes, and any download
71 : : * sources realistically need to support SegWit in order to provide useful data,
72 : : * so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
73 : : * is uninteresting.
74 : : */
75 : : BLOCK_RECENT_CONSENSUS_CHANGE,
76 : : BLOCK_CACHED_INVALID, //!< this block was cached as being invalid and we didn't store the reason why
77 : : BLOCK_INVALID_HEADER, //!< invalid proof of work or time too old
78 : : BLOCK_MUTATED, //!< the block's data didn't match the data committed to by the PoW
79 : : BLOCK_MISSING_PREV, //!< We don't have the previous block the checked one is built on
80 : : BLOCK_INVALID_PREV, //!< A block this one builds on is invalid
81 : : BLOCK_TIME_FUTURE, //!< block timestamp was > 2 hours in the future (or our clock is bad)
82 : : BLOCK_CHECKPOINT, //!< the block failed to meet one of our checkpoints
83 : : BLOCK_HEADER_LOW_WORK //!< the block header may be on a too-little-work chain
84 : : };
85 : :
86 : :
87 : :
88 : : /** Template for capturing information about block/transaction validation. This is instantiated
89 : : * by TxValidationState and BlockValidationState for validation information on transactions
90 : : * and blocks respectively. */
91 : : template <typename Result>
92 : 7874924 : class ValidationState
93 : : {
94 : : private:
95 : : enum class ModeState {
96 : : M_VALID, //!< everything ok
97 : : M_INVALID, //!< network rule violation (DoS value may be set)
98 : : M_ERROR, //!< run-time error
99 : 4181902 : } m_mode{ModeState::M_VALID};
100 : 4181902 : Result m_result{};
101 : : std::string m_reject_reason;
102 : : std::string m_debug_message;
103 : :
104 : : public:
105 : 1341167 : bool Invalid(Result result,
106 : : const std::string& reject_reason = "",
107 : : const std::string& debug_message = "")
108 : : {
109 : 1341167 : m_result = result;
110 : 1341167 : m_reject_reason = reject_reason;
111 : 1341167 : m_debug_message = debug_message;
112 [ - + - + : 1341167 : if (m_mode != ModeState::M_ERROR) m_mode = ModeState::M_INVALID;
- + ][ - + ]
113 : 1341167 : return false;
114 : : }
115 : 638 : bool Error(const std::string& reject_reason)
116 : : {
117 [ + + ]: 638 : if (m_mode == ModeState::M_VALID)
118 : 12 : m_reject_reason = reject_reason;
119 : 638 : m_mode = ModeState::M_ERROR;
120 : 638 : return false;
121 : : }
122 : 1590037 : bool IsValid() const { return m_mode == ModeState::M_VALID; }
123 : 275968 : bool IsInvalid() const { return m_mode == ModeState::M_INVALID; }
124 : 120133 : bool IsError() const { return m_mode == ModeState::M_ERROR; }
125 : 1242841 : Result GetResult() const { return m_result; }
126 : 15789 : std::string GetRejectReason() const { return m_reject_reason; }
127 : 15604 : std::string GetDebugMessage() const { return m_debug_message; }
128 : 256997 : std::string ToString() const
129 : : {
130 [ + - + - ]: 256997 : if (IsValid()) {
[ + + ]
131 [ # # # # ]: 126207 : return "Valid";
[ + - ]
132 : : }
133 : :
134 [ + - + - ]: 130790 : if (!m_debug_message.empty()) {
[ + + ]
135 [ # # # # ]: 77486 : return m_reject_reason + ", " + m_debug_message;
[ + - ]
136 : : }
137 : :
138 : 53304 : return m_reject_reason;
139 : 256997 : }
140 : : };
141 : :
142 : : class TxValidationState : public ValidationState<TxValidationResult> {};
143 : : class BlockValidationState : public ValidationState<BlockValidationResult> {};
144 : :
145 : : // These implement the weight = (stripped_size * 4) + witness_size formula,
146 : : // using only serialization with and without witness data. As witness_size
147 : : // is equal to total_size - stripped_size, this formula is identical to:
148 : : // weight = (stripped_size * 3) + total_size.
149 : 3352905 : static inline int32_t GetTransactionWeight(const CTransaction& tx)
150 : : {
151 : 3352905 : return ::GetSerializeSize(TX_NO_WITNESS(tx)) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(TX_WITH_WITNESS(tx));
152 : : }
153 : 495352 : static inline int64_t GetBlockWeight(const CBlock& block)
154 : : {
155 : 495352 : return ::GetSerializeSize(TX_NO_WITNESS(block)) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(TX_WITH_WITNESS(block));
156 : : }
157 : 258 : static inline int64_t GetTransactionInputWeight(const CTxIn& txin)
158 : : {
159 : : // scriptWitness size is added here because witnesses and txins are split up in segwit serialization.
160 : 258 : return ::GetSerializeSize(TX_NO_WITNESS(txin)) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(TX_WITH_WITNESS(txin)) + ::GetSerializeSize(txin.scriptWitness.stack);
161 : : }
162 : :
163 : : /** Compute at which vout of the block's coinbase transaction the witness commitment occurs, or -1 if not found */
164 : 1037472 : inline int GetWitnessCommitmentIndex(const CBlock& block)
165 : : {
166 : 1037472 : int commitpos = NO_WITNESS_COMMITMENT;
167 [ + + ]: 1037472 : if (!block.vtx.empty()) {
168 [ + + ]: 3534665 : for (size_t o = 0; o < block.vtx[0]->vout.size(); o++) {
169 : 2497206 : const CTxOut& vout = block.vtx[0]->vout[o];
170 [ + + + + ]: 3210574 : if (vout.scriptPubKey.size() >= MINIMUM_WITNESS_COMMITMENT &&
171 [ + + ]: 731332 : vout.scriptPubKey[0] == OP_RETURN &&
172 [ + + ]: 714570 : vout.scriptPubKey[1] == 0x24 &&
173 [ + + ]: 714195 : vout.scriptPubKey[2] == 0xaa &&
174 [ + + ]: 714129 : vout.scriptPubKey[3] == 0x21 &&
175 [ + + ]: 713573 : vout.scriptPubKey[4] == 0xa9 &&
176 : 713368 : vout.scriptPubKey[5] == 0xed) {
177 : 712276 : commitpos = o;
178 : 712276 : }
179 : 2497206 : }
180 : 1037459 : }
181 : 2074944 : return commitpos;
182 : 1037472 : }
183 : :
184 : : #endif // BITCOIN_CONSENSUS_VALIDATION_H
|