Differenct signature result with other libraries

[FaiChou]

I am using the sample code to test:

let privateBytes = try! "14E4A74438858920D8A35FB2D88677580B6A2EE9BE4E711AE34EC6B396D87B5C".bytes
let privateKey = try! secp256k1.Signing.PrivateKey(rawRepresentation: privateBytes)
print("private key: \(String(bytes: privateKey.rawRepresentation))")
print("public key: \(String(bytes: privateKey.publicKey.rawRepresentation))")
// ECDSA
let str = "We're all Satoshi."
let messageData = str.data(using: .utf8)!
let signature = try! privateKey.ecdsa.signature(for: messageData)
print("signature: \(String(bytes: signature.rawRepresentation))")

the results are:

private key: 14e4a74438858920d8a35fb2d88677580b6a2ee9be4e711ae34ec6b396d87b5c
public key: 02734b3511150a60fc8cac329cd5ff804555728740f2f2e98bc4242135ef5d5e4e
signature: 09b7cc8f9c570c6cec33e926615879c7b4ad0dbdfed2180d893f0de50d31063e1201f0847ea4b43c4e3f13955a19a53f52a9a7eddaec3368efa2a45d172bf456

When I put the same private key and message to the other libraries, the values are not the same, you can test on the website: https://paulmillr.com/noble/

[csjones]

Hi @FaiChou

Looks like you are trying to compare signatures with a compact representation. Have you tried using the compactRepresentation property?

let signature = try! privateKey.ecdsa.signature(for: messageData).compactRepresentation

[FaiChou]

@csjones thanks, a great help

[aheze]

Awesome, had the same issue and this worked great!