Sighash
bitcoin · scripting
Signature-hash flags that define which transaction parts a signature commits to in Bitcoin-style scripts.
1.definition
Sighash, short for signature hash, defines the transaction data covered by a signature. Common modes include ALL, NONE, SINGLE, and ANYONECANPAY variants, which control whether the signature commits to all inputs and outputs or only selected parts.
2.use-cases
Sighash flags enable advanced contracts and multi-party transaction construction, but they are consensus-sensitive and chain-specific. Wallets should choose flags carefully because signing too little can allow another party to change parts of the transaction.
Related terms
Signature
→A cryptographic proof that a message was authorized by the holder of a private key.
cryptography
Transaction
→A serialized state transition that a blockchain can validate, relay, and include in a block.
blockchain · technical
Opcode
→An encoded instruction interpreted by a virtual machine or transaction script engine.
technical · scripting