Swift

RSA Hash Binary Data and Sign (and Verify)

See more RSA Examples

Demonstrates how to sign the hash of binary data. Also demonstrates how to verify the RSA signature. Swift

func chilkatTest() {
    var success: Bool = false

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Load an RSA private key for signing.
    let privKey = CkoPrivateKey()!
    success = privKey.loadEncryptedPemFile(path: "qa_data/pem/rsa_passwd.pem", password: "passwd")
    if success == false {
        print("\(privKey.lastErrorText!)")
        return
    }

    let rsa = CkoRsa()!
    rsa.usePrivateKey(privKey: privKey)

    // We have some binary data (in hex) to sign
    var originalData: String? = "0102030405060708090A"
    let bdData = CkoBinData()!
    bdData.appendEncoded(encData: originalData, encoding: "hex")

    // Hash (SHA-256) and sign the hash:
    let bdSignature = CkoBinData()!
    success = rsa.signBd(bdData: bdData, hashAlgorithm: "sha256", bdSig: bdSignature)
    if success == false {
        print("\(rsa.lastErrorText!)")
        return
    }

    // Show the RSA signature in base64
    print("\(bdSignature.getEncoded(encoding: "base64")!)")

    // ------------------------------------------
    // Get the public key from the private key
    let pubKey = CkoPublicKey()!
    privKey.toPublicKey(pubKey: pubKey)

    // Verify the signature..
    let rsa2 = CkoRsa()!
    rsa2.usePublicKey(pubKey: pubKey)

    var bVerified: Bool = rsa2.verifyBd(bdData: bdData, hashAlgorithm: "sha256", bdSig: bdSignature)
    print("signature verified: \(bVerified)")

}