(Go) RSA Sign with PKCS8 Encrypted Key

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature (and then verify it).

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

    pkey := chilkat.NewPrivateKey()

    // Load the private key from an RSA PEM file:
    success := pkey.LoadPkcs8EncryptedFile("raul_privateKey.key","a0123456789")

    var pkeyXml *string = new(string)
    // Get the private key in XML format:
    pkeyXml = pkey.GetXml()

    rsa := chilkat.NewRsa()

    // Import the private key into the RSA component:
    success = rsa.ImportPrivateKey(*pkeyXml)
    if success != true {
        fmt.Println(rsa.LastErrorText())
        pkey.DisposePrivateKey()
        rsa.DisposeRsa()
        return
    }

    // This example will sign a string, and receive the signature
    // in a hex-encoded string.  Therefore, set the encoding mode
    // to "hex":
    rsa.SetEncodingMode("hex")

    strData := "This is the string to be signed."

    // Sign the string using the sha-1 hash algorithm.
    // Other valid choices are "md2" and "md5".
    hexSig := rsa.SignStringENC(strData,"sha-1")

    fmt.Println(*hexSig)

    // Now verify with the public key.
    // This example shows how to use the public key from 
    // a digital certificate (.cer file)
    cert := chilkat.NewCert()
    success = cert.LoadFromFile("raul_publicKey.cer")
    if success != true {
        fmt.Println(cert.LastErrorText())
        pkey.DisposePrivateKey()
        rsa.DisposeRsa()
        cert.DisposeCert()
        return
    }

    // pubKey is a PublicKey
    pubKey := cert.ExportPublicKey()

    var pubKeyXml *string = new(string)
    // Get the private key in XML format:
    pubKeyXml = pubKey.GetXml()

    rsa2 := chilkat.NewRsa()
    success = rsa2.ImportPublicKey(*pubKeyXml)
    if success != true {
        fmt.Println(rsa2.LastErrorText())
        pkey.DisposePrivateKey()
        rsa.DisposeRsa()
        cert.DisposeCert()
        rsa2.DisposeRsa()
        return
    }

    // Verify the signature against the original data:
    rsa2.SetEncodingMode("hex")
    success = rsa2.VerifyStringENC(strData,"sha-1",*hexSig)
    if success != true {
        fmt.Println(rsa2.LastErrorText())
        pkey.DisposePrivateKey()
        rsa.DisposeRsa()
        cert.DisposeCert()
        rsa2.DisposeRsa()
        return
    }

    fmt.Println("Signature verified!")

    // Verify with incorrect data:
    success = rsa2.VerifyStringENC("something else","sha-1",*hexSig)
    if success != true {
        fmt.Println("Signature not verified! (which was expected in this case)")
    }
    else {
        fmt.Println("Hmmm... that's not right...")
    }

    pubKey.DisposePublicKey()

    pkey.DisposePrivateKey()
    rsa.DisposeRsa()
    cert.DisposeCert()
    rsa2.DisposeRsa()