(Go) 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 Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

    // 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.LoadPemFile("myKey.pem")

    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
    }

    // OpenSSL uses BigEndian byte ordering:
    rsa.SetLittleEndian(false)

    // The resulting signature will be a Base64 string:
    rsa.SetEncodingMode("base64")

    // For simplicity, we're not loading
    // the data to be signed from a file.  We are instead simply
    // using a literal string value.  
    strData := "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".
    base64Sig := rsa.SignStringENC(strData,"md5")

    fmt.Println(*base64Sig)

    fmt.Println("Success!")

    pkey.DisposePrivateKey()
    rsa.DisposeRsa()