Struct BSM 

pub struct BSM;

Bitcoin Signed Messages (BSM) – legacy message signing and verification.

BSM uses a magic prefix to prevent cross-protocol signature attacks. Messages are double-SHA256 hashed with the prefix before signing.

Implementations

impl BSM

pub fn magic_hash(message: &[u8]) -> [u8; 32]

Compute the BSM magic hash of a message.

Constructs the prefixed buffer: VarInt(25) || “Bitcoin Signed Message:\n” || VarInt(message.len()) || message

Then returns hash256 (double SHA-256) of the buffer.

pub fn sign( message: &[u8], private_key: &PrivateKey, ) -> Result<Vec<u8>, CompatError>

Sign a message using BSM.

Returns a 65-byte compact BSM signature (recovery byte + 32-byte r + 32-byte s). The magic hash is computed, then ECDSA signing is performed with the hash256 output. Recovery factor is calculated and encoded in the first byte.

pub fn verify( message: &[u8], sig_bytes: &[u8], pub_key: &PublicKey, ) -> Result<bool, CompatError>

Verify a BSM signed message.

The signature must be in 65-byte compact BSM format. Verifies the signature against the provided public key.