Swift Requires Chilkat v10.1.2+

RSA Sign String using Private Key of Certificate Type A3 (smart card / token)

See more RSA Examples

Demonstrates RSA signing a string using the private key of a certificate type A3 (smart card, token).

Note: This is a Windows-only example.

Swift

func chilkatTest() {
    var success: Bool = false

    //  First get the A3 certificate that was installed on the Windows system.
    let certStore = CkoCertStore()!

    var thumbprint: String? = "12c1dd8015f3f03f7b1fa619dc24e2493ca8b4b2"

    //  This is specific to Windows because it is opening the Windows Current-User certificate store.
    var bReadOnly: Bool = true
    success = certStore.openCurrentUserStore(readOnly: bReadOnly)
    if success != true {
        print("\(certStore.lastErrorText!)")
        return
    }

    //  Find the certificate with the desired thumbprint
    //  (There are many ways to locate a certificate.  This example chooses to find by thumbprint.)
    let json = CkoJsonObject()!
    json.updateString(jsonPath: "thumbprint", value: thumbprint)

    let cert = CkoCert()!
    success = certStore.findCert(json: json, cert: cert)
    if success == false {
        print("Failed to find the certificate.")
        return
    }

    print("Found: \(cert.subjectCN!)")

    let rsa = CkoRsa()!

    //  Provide the cert's private key
    var bUsePrivateKey: Bool = true
    success = rsa.setX509Cert(cert: cert, usePrivateKey: bUsePrivateKey)
    if success != true {
        print("\(rsa.lastErrorText!)")
        return
    }

    //  Return the RSA signature in base64 encoded form.
    rsa.encodingMode = "base64"

    //  Sign the utf-8 byte representation of the string.
    rsa.charset = "utf-8"

    //  You can also choose other hash algorithms, such as SHA-1.
    var sigBase64: String? = rsa.signStringENC(str: "text to sign", hashAlg: "SHA-256")
    if rsa.lastMethodSuccess != true {
        print("\(rsa.lastErrorText!)")
        return
    }

    print("Base64 signature: \(sigBase64!)")

}