(Swift 3,4,5...) Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:

openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    let pkey = CkoPrivateKey()!

    // Load the private key from an RSA PEM file:
    var success: Bool = pkey.loadPemFile("myKey.pem")

    var pkeyXml: String?

    // Get the private key in XML format:
    pkeyXml = pkey.getXml()

    let rsa = CkoRsa()!

    // Import the private key into the RSA component:
    success = rsa.importPrivateKey(pkeyXml)
    if success != true {
        print("\(rsa.lastErrorText!)")
        return
    }

    // OpenSSL uses BigEndian byte ordering:
    rsa.littleEndian = false

    // The resulting signature will be a Base64 string:
    rsa.encodingMode = "base64"

    // For simplicity, we're not loading
    // the data to be signed from a file.  We are instead simply
    // using a literal string value.  
    var strData: String? = "This is the text to be signed."

    // Hash the input using MD5, and then sign the hash:
    // Other valid hash algorithm choices are "md2" and "sha-1".
    var base64Sig: String? = rsa.signStringENC(strData, hashAlg: "md5")

    print("\(base64Sig!)")

    print("Success!")

}