Validate a JWS with a Public Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPublicKey, which sets the public key used to validate a signature of a loaded JWS.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

func chilkatTest() {
    var success: Bool = false

    let jws = CkoJws()!

    //  Load the JWS compact serialization.
    var jwsCompact: String? = "eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>"
    success = jws.load(jwsStr: jwsCompact)
    if success == false {
        print("\(jws.lastErrorText!)")
        return
    }

    //  The file path is relative to the application's current working directory.  An absolute path
    //  may also be used.  Supply the path appropriate to your own environment.
    //  Load the signer's public key and set it for validating signature 0.
    let pubKey = CkoPublicKey()!
    success = pubKey.load(fromFile: "qa_data/signer_pubkey.pem")
    if success == false {
        print("\(pubKey.lastErrorText!)")
        return
    }

    success = jws.setPublicKey(index: 0, pubKey: pubKey)
    if success == false {
        print("\(jws.lastErrorText!)")
        return
    }

    //  Validate the signature.  Validate returns 1 when valid, 0 when not, or a negative value on error.
    var v: Int = jws.validate(index: 0).intValue
    if v < 0 {
        print("\(jws.lastErrorText!)")
        return
    }

    if v != 1 {
        print("The signature is not valid.")
        return
    }

    print("The signature is valid.")

}