(Swift 3,4,5...) Duplicate OpensSSL to Sign File and Output Binary DER

This example duplicates the following:

openssl smime -sign -in INPUT.xml -signer SIGN.PEM -passin pass:MYPASS -outform der -binary -nodetach -out SIGNED.P7M

Note: Although "smime" is the OpenSSL command, it's not actually producing S/MIME. The arguments "-outform der -binary" indicates that the output is binary DER (i.e. the PKCS7 binary signature). The input can be any type of file: XML, PDF, JPG, ... *anything*...

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

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

    let crypt = CkoCrypt2()!

    // Load the PEM containing cert + private key.
    let pem = CkoPem()!
    var success: Bool = pem.loadFile("qa_data/pem/myPem.pem", password: "password")
    if success != true {
        print("\(pem.lastErrorText!)")
        return
    }

    var privkey: CkoPrivateKey? = pem.getPrivateKey(0)
    if pem.lastMethodSuccess != true {
        print("\(pem.lastErrorText!)")
        return
    }

    var cert: CkoCert? = pem.getCert(0)
    if pem.lastMethodSuccess != true {
        privkey = nil
        print("\(pem.lastErrorText!)")
        return
    }

    success = crypt.setSigningCert2(cert, key: privkey)
    if success != true {
        privkey = nil
        cert = nil
        print("\(crypt.lastErrorText!)")
        return
    }

    privkey = nil
    cert = nil

    // Alternatively, we could use a .pfx/.p12 file.
    // (Chilkat also supports other formats/sources for cert/private keys...)
    let certFromP12 = CkoCert()!
    success = certFromP12.loadPfxFile("qa_data/p12/myP12.p12", password: "password")
    if success != true {
        print("\(certFromP12.lastErrorText!)")
        return
    }

    // The certificate, when loaded from a .pfx/.p12, will automatically 
    // include the associated private key, assuming it's present in the .p12.
    // We don't have to explicitly provide the private key as in the
    // lines of code above that use the PEM file.
    success = crypt.setSigning(certFromP12)
    if success != true {
        print("\(crypt.lastErrorText!)")
        return
    }

    // Create the opaque signature (PKCS7 binary DER that contains both the signature and original file data).
    success = crypt.createP7M("qa_data/infile.anything", p7mPath: "qa_output/outfile.p7m")
    if success != true {
        print("\(crypt.lastErrorText!)")
        return
    }

    print("Success.")

}