sign the passed in message (usually the output of a hash function).parammessage the message to be signed.returntwo big integers representing the r and s values respectively.
initialise the signer for signature generation or signature verification.paramforSigning true if we are generating a signature, false otherwise.paramparam key parameters for signature generation.
verify the message message against the signature values r and s.parammessage the message that was supposed to have been signed.paramr the r signature value.params the s signature value.