secp256k1 helpers for Hedera's ECDSA signature convention: signatures are the
64-byte raw r ‖ s form with s normalized to the lower half of the curve
order (low-S, as required by Hedera/Ethereum), and public keys are the 33-byte
compressed form on the wire. OpenSSL (via OTP :crypto) produces DER
signatures and uncompressed points, which these functions convert.
Summary
Functions
Compress an uncompressed secp256k1 point (0x04 ‖ X ‖ Y) to 33 bytes.
Convert a DER ECDSA signature to canonical 64-byte r ‖ s (low-S).
Convert a canonical 64-byte r ‖ s signature to DER.
Functions
Compress an uncompressed secp256k1 point (0x04 ‖ X ‖ Y) to 33 bytes.
Convert a DER ECDSA signature to canonical 64-byte r ‖ s (low-S).
Convert a canonical 64-byte r ‖ s signature to DER.