diff --git a/src/script/standard.cpp b/src/script/standard.cpp index 0f720d9e7..2aed39392 100644 --- a/src/script/standard.cpp +++ b/src/script/standard.cpp @@ -34,9 +34,6 @@ const char* GetTxnOutputType(txnouttype t) return nullptr; } -/** - * Return public keys or hashes from scriptPubKey, for 'standard' transaction types. - */ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector >& vSolutionsRet) { // Templates diff --git a/src/script/standard.h b/src/script/standard.h index 097e0c374..761919226 100644 --- a/src/script/standard.h +++ b/src/script/standard.h @@ -27,8 +27,19 @@ public: CScriptID(const uint160& in) : uint160(in) {} }; -static const unsigned int MAX_OP_RETURN_RELAY = 83; //!< bytes (+1 for OP_RETURN, +2 for the pushdata opcodes) +/** + * Default setting for nMaxDatacarrierBytes. 80 bytes of data, +1 for OP_RETURN, + * +2 for the pushdata opcodes. + */ +static const unsigned int MAX_OP_RETURN_RELAY = 83; + +/** + * A data carrying output is an unspendable output containing data. The script + * type is designated as TX_NULL_DATA. + */ extern bool fAcceptDatacarrier; + +/** Maximum size of TX_NULL_DATA scripts that this node considers standard. */ extern unsigned nMaxDatacarrierBytes; /** @@ -36,7 +47,7 @@ extern unsigned nMaxDatacarrierBytes; * them to be valid. (but old blocks may not comply with) Currently just P2SH, * but in the future other flags may be added, such as a soft-fork to enforce * strict DER encoding. - * + * * Failing one of these tests may trigger a DoS ban - see CheckInputs() for * details. */ @@ -50,7 +61,7 @@ enum txnouttype TX_PUBKEYHASH, TX_SCRIPTHASH, TX_MULTISIG, - TX_NULL_DATA, + TX_NULL_DATA, //!< unspendable OP_RETURN script that carries data TX_WITNESS_V0_SCRIPTHASH, TX_WITNESS_V0_KEYHASH, }; @@ -61,7 +72,7 @@ public: friend bool operator<(const CNoDestination &a, const CNoDestination &b) { return true; } }; -/** +/** * A txout script template with a specific destination. It is either: * * CNoDestination: no destination set * * CKeyID: TX_PUBKEYHASH destination @@ -70,15 +81,58 @@ public: */ typedef boost::variant CTxDestination; +/** Get the name of a txnouttype as a C string, or nullptr if unknown. */ const char* GetTxnOutputType(txnouttype t); +/** + * Parse a scriptPubKey and identify script type for standard scripts. If + * successful, returns script type and parsed pubkeys or hashes, depending on + * the type. For example, for a P2SH script, vSolutionsRet will contain the + * script hash, for P2PKH it will contain the key hash, etc. + * + * @param[in] scriptPubKey Script to parse + * @param[out] typeRet The script type + * @param[out] vSolutionsRet Vector of parsed pubkeys and hashes + * @return True if script matches standard template + */ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, std::vector >& vSolutionsRet); + +/** + * Parse a standard scriptPubKey for the destination address. Assigns result to + * the addressRet parameter and returns true if successful. For multisig + * scripts, instead use ExtractDestinations. Currently only works for P2PK, + * P2PKH, and P2SH scripts. + */ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet); + +/** + * Parse a standard scriptPubKey with one or more destination addresses. For + * multisig scripts, this populates the addressRet vector with the pubkey IDs + * and nRequiredRet with the n required to spend. For other destinations, + * addressRet is populated with a single value and nRequiredRet is set to 1. + * Returns true if successful. Currently does not extract address from + * pay-to-witness scripts. + */ bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, std::vector& addressRet, int& nRequiredRet); +/** + * Generate a Bitcoin scriptPubKey for the given CTxDestination. Returns a P2PKH + * script for a CKeyID destination, a P2SH script for a CScriptID, and an empty + * script for CNoDestination. + */ CScript GetScriptForDestination(const CTxDestination& dest); + +/** Generate a P2PK script for the given pubkey. */ CScript GetScriptForRawPubKey(const CPubKey& pubkey); + +/** Generate a multisig script. */ CScript GetScriptForMultisig(int nRequired, const std::vector& keys); + +/** + * Generate a pay-to-witness script for the given redeem script. If the redeem + * script is P2PK or P2PKH, this returns a P2WPKH script, otherwise it returns a + * P2WSH script. + */ CScript GetScriptForWitness(const CScript& redeemscript); #endif // BITCOIN_SCRIPT_STANDARD_H