Module BSV::Primitives::BSM ¶

Bitcoin Signed Messages (BSM).

Signs and verifies messages using the standard Bitcoin message signing protocol. Messages are prefixed with +"Bitcoin Signed Message:n"+, length-prefixed, and double-SHA-256 hashed before signing with recoverable ECDSA. Signatures are 65-byte compact format, base64-encoded.

@example Sign and verify a message

key = BSV::Primitives::PrivateKey.generate
sig = BSV::Primitives::BSM.sign('hello', key)
BSV::Primitives::BSM.verify('hello', sig, key.public_key.address) #=> true

Constants¶

MAGIC_PREFIX ¶

The standard Bitcoin message signing prefix.

Public Class Methods¶

magic_hash(message) ¶

Compute the double-SHA-256 hash of a Bitcoin-prefixed message. - @param message [String] the message to hash - @return [String] 32-byte double-SHA-256 digest

sign(message, private_key) ¶

Sign a message with a private key.

Produces a 65-byte compact recoverable signature encoded as base64. The flag byte (31-34) indicates compressed P2PKH recovery per BIP-137. - @param message [String] the message to sign - @param private_key [PrivateKey] the signing key - @return [String] base64-encoded compact signature

verify(message, signature, address) ¶

Verify a signed message against a Bitcoin address.

Recovers the public key from the compact signature and checks whether the derived address matches the expected address. - @param message [String] the original message - @param signature [String] base64-encoded compact signature - @param address [String] the expected Bitcoin address - @raise [ArgumentError] if the signature encoding or flag byte is invalid - @return [Boolean] +true+ if the signature is valid for the given address