Shared Libraries ================ ## bitcoinconsensus The purpose of this library is to make the verification functionality that is critical to Bitcoin's consensus available to other applications, e.g. to language bindings. ### API The interface is defined in the C header `bitcoinconsensus.h` located in `src/script/bitcoinconsensus.h`. #### Version `bitcoinconsensus_version` returns an `unsigned int` with the API version *(currently `1`)*. #### Script Validation `bitcoinconsensus_verify_script` returns an `int` with the status of the verification. It will be `1` if the input script correctly spends the previous output `scriptPubKey`. ##### Parameters - `const unsigned char *scriptPubKey` - The previous output script that encumbers spending. - `unsigned int scriptPubKeyLen` - The number of bytes for the `scriptPubKey`. - `const unsigned char *txTo` - The transaction with the input that is spending the previous output. - `unsigned int txToLen` - The number of bytes for the `txTo`. - `unsigned int nIn` - The index of the input in `txTo` that spends the `scriptPubKey`. - `unsigned int flags` - The script validation flags *(see below)*. - `bitcoinconsensus_error* err` - Will have the error/success code for the operation *(see below)*. ##### Script Flags - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_NONE` - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_P2SH` - Evaluate P2SH ([BIP16](https://github.com/bitcoin/bips/blob/master/bip-0016.mediawiki)) subscripts - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_DERSIG` - Enforce strict DER ([BIP66](https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki)) compliance - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_NULLDUMMY` - Enforce NULLDUMMY ([BIP147](https://github.com/bitcoin/bips/blob/master/bip-0147.mediawiki)) - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_CHECKLOCKTIMEVERIFY` - Enable CHECKLOCKTIMEVERIFY ([BIP65](https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki)) - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_CHECKSEQUENCEVERIFY` - Enable CHECKSEQUENCEVERIFY ([BIP112](https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki)) - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS` - Enable WITNESS ([BIP141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki)) ##### Errors - `bitcoinconsensus_ERR_OK` - No errors with input parameters *(see the return value of `bitcoinconsensus_verify_script` for the verification status)* - `bitcoinconsensus_ERR_TX_INDEX` - An invalid index for `txTo` - `bitcoinconsensus_ERR_TX_SIZE_MISMATCH` - `txToLen` did not match with the size of `txTo` - `bitcoinconsensus_ERR_DESERIALIZE` - An error deserializing `txTo` - `bitcoinconsensus_ERR_AMOUNT_REQUIRED` - Input amount is required if WITNESS is used - `bitcoinconsensus_ERR_INVALID_FLAGS` - Script verification `flags` are invalid (i.e. not part of the libconsensus interface) ### Example Implementations - [NBitcoin](https://github.com/MetacoSA/NBitcoin/blob/5e1055cd7c4186dee4227c344af8892aea54faec/NBitcoin/Script.cs#L979-#L1031) (.NET Bindings) - [node-libbitcoinconsensus](https://github.com/bitpay/node-libbitcoinconsensus) (Node.js Bindings) - [java-libbitcoinconsensus](https://github.com/dexX7/java-libbitcoinconsensus) (Java Bindings) - [bitcoinconsensus-php](https://github.com/Bit-Wasp/bitcoinconsensus-php) (PHP Bindings)