(Go) PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file.

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

    cert := chilkat.NewCert()

    // Load the cert and private key.  Whatever the private key happens to be,
    // such as RSA or ECC, then Chilkat will use it.  If the private key is 
    // a 2048-bit RSA key, then that's what will be used..
    success := cert.LoadPfxFile("qa_data/pfx/myCertAndKey.p12","password")
    if success != true {
        fmt.Println(cert.LastErrorText())
        cert.DisposeCert()
        return
    }

    crypt := chilkat.NewCrypt2()

    success = crypt.SetSigningCert(cert)
    if success != true {
        fmt.Println(crypt.LastErrorText())
        cert.DisposeCert()
        crypt.DisposeCrypt2()
        return
    }

    // Use SHA-256
    crypt.SetHashAlgorithm("sha256")

    // Hash the utf-8 byte representation of the string
    crypt.SetCharset("utf-8")

    // Return the result in base64
    crypt.SetEncodingMode("base64")

    // Sign some text..
    textToSign := "This is the text to be hashed and signed."
    sigBase64 := crypt.OpaqueSignStringENC(textToSign)
    if crypt.LastMethodSuccess() != true {
        fmt.Println(crypt.LastErrorText())
        cert.DisposeCert()
        crypt.DisposeCrypt2()
        return
    }

    fmt.Println(*sigBase64)

    // The result:
    // MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==

    cert.DisposeCert()
    crypt.DisposeCrypt2()