(DataFlex) Get Public Key from CSR

Demonstrates how to get the public key from a CSR.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoPem
    String sNoPassword
    Boolean iSuccess
    String sStrBase64
    Handle hoAsn
    Handle hoXml
    String sStrModulusHex
    Handle hoBd
    String sModulus64
PubKey    Handle hoXmlPubKey
    Handle hoPubkey
    Boolean iPreferPkcs1
    String sTemp1

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

    Get Create (RefClass(cComChilkatPem)) To hoPem
    If (Not(IsComObjectCreated(hoPem))) Begin
        Send CreateComObject of hoPem
    End

    // No password is required.  Pass an empty password string..
    Move "" To sNoPassword
    Get ComLoadPemFile Of hoPem "qa_data/csr/csr2.pem" sNoPassword To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoPem To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComGetEncodedItem Of hoPem "csr" "" "base64" 0 To sStrBase64

    Get Create (RefClass(cComChilkatAsn)) To hoAsn
    If (Not(IsComObjectCreated(hoAsn))) Begin
        Send CreateComObject of hoAsn
    End
    Get ComLoadEncoded Of hoAsn sStrBase64 "base64" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoAsn To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Convert the ASN.1 to XML.
    Get Create (RefClass(cComChilkatXml)) To hoXml
    If (Not(IsComObjectCreated(hoXml))) Begin
        Send CreateComObject of hoXml
    End
    Get ComAsnToXml Of hoAsn To sTemp1
    Get ComLoadXml Of hoXml sTemp1 To iSuccess
    Get ComGetXml Of hoXml To sTemp1
    Showln sTemp1
    Showln "----"

    Get ComGetChildContent Of hoXml "bits" To sStrModulusHex
    Showln "strModulusHex = " sStrModulusHex
    Showln "----"

    // We need the modulus as base64.
    Get Create (RefClass(cComChilkatBinData)) To hoBd
    If (Not(IsComObjectCreated(hoBd))) Begin
        Send CreateComObject of hoBd
    End
    Get ComAppendEncoded Of hoBd sStrModulusHex "hex" To iSuccess
    Get ComGetEncoded Of hoBd "base64" To sModulus64
    Showln "modulus64 = " sModulus64
    Showln "----"

    // Build the XML for the public key.
    Get Create (RefClass(cComChilkatXml)) To hoXmlPubKey
    If (Not(IsComObjectCreated(hoXmlPubKey))) Begin
        Send CreateComObject of hoXmlPubKey
    End
    Set ComTag Of hoXmlPubKey To "RSAPublicKey"
    Send ComUpdateChildContent To hoXmlPubKey "Modulus" sModulus64
    // The RSA exponent will always be decimal 65537 (base64 = AQAB)
    Send ComUpdateChildContent To hoXmlPubKey "Exponent" "AQAB"

    Showln "RSA public key as XML:"
    Get ComGetXml Of hoXmlPubKey To sTemp1
    Showln sTemp1
    Showln "----"

    // Load the XML into a Chilkat public key object.
    Get Create (RefClass(cComChilkatPublicKey)) To hoPubkey
    If (Not(IsComObjectCreated(hoPubkey))) Begin
        Send CreateComObject of hoPubkey
    End
    Get ComGetXml Of hoXmlPubKey To sTemp1
    Get ComLoadFromString Of hoPubkey sTemp1 To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoPubkey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Show the public key as PEM.
    Move True To iPreferPkcs1
    Get ComGetPem Of hoPubkey iPreferPkcs1 To sTemp1
    Showln sTemp1


End_Procedure