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DataFlex

Duplicate openssl req -newkey rsa:2048 -nodes -keyout mydomain.pem -out mydomain.csr

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command: 
openssl req -newkey rsa:2048 -nodes -keyout mydomain.pem -out mydomain.csr

This command creates 2 files:

  1. mydomain.csr: this is the file to send to DigiCert or Let's Encrypt (or any other CA)
  2. mydomain.pem: this is the private key of the domain.

The second file is needed to pair with the certificate that will later be received from the CA.

Chilkat DataFlex Downloads

Download Chilkat for DataFlex
DataFlex 
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoRsa
    Variant vPrivKey
    Handle hoPrivKey
    Variant vPrivKey
Xml    Handle hoPrivKeyXml
    String sKeyModulus
    Handle hoAsnRoot
    Variant vAsnCertReqInfo
    Handle hoAsnCertReqInfo
    Variant vAsnCertSubject
    Handle hoAsnCertSubject
    Variant vAsnTemp
    Handle hoAsnTemp
    Variant vAsnPubKeyInfo
    Handle hoAsnPubKeyInfo
    Variant vAsnPubKeyAlgId
    Handle hoAsnPubKeyAlgId
    Handle hoAsnRsaKey
    String sRsaKeyDerBase64
    Variant vBdDer
    Handle hoBdDer
    Variant vBdSig
    Handle hoBdSig
    Variant vAsnAlgId
    Handle hoAsnAlgId
    String sCsrBase64
    String sTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatRsa)) To hoRsa
    If (Not(IsComObjectCreated(hoRsa))) Begin
        Send CreateComObject of hoRsa
    End

    // Generate a 2048-bit key.  Chilkat RSA supports
    // key sizes ranging from 512 bits to 8192 bits.
    Get Create (RefClass(cComChilkatPrivateKey)) To hoPrivKey
    If (Not(IsComObjectCreated(hoPrivKey))) Begin
        Send CreateComObject of hoPrivKey
    End
    Get pvComObject of hoPrivKey to vPrivKey
    Get ComGenKey Of hoRsa 2048 vPrivKey To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get pvComObject of hoPrivKey to vPrivKey
    Get ComUsePrivateKey Of hoRsa vPrivKey To iSuccess

    // Save the private key to unencrypted PKCS8 PEM
    Get ComSavePkcs8PemFile Of hoPrivKey "mydomain.pem" To iSuccess

    // (alternatively) Save the private key to encrypted PKCS8 PEM
    Get ComSavePkcs8EncryptedPemFile Of hoPrivKey "myPassword" "mydomain_enc.pem" To iSuccess

    // We'll need the private key's modulus for the CSR.
    // The modulus is not something that needs to be protected.  Most people don't realize
    // that a public key is actually just a subset of the private key.  The public parts of
    // an RSA private key are the modulus and exponent.  The exponent is always 65537.
    Get Create (RefClass(cComChilkatXml)) To hoPrivKeyXml
    If (Not(IsComObjectCreated(hoPrivKeyXml))) Begin
        Send CreateComObject of hoPrivKeyXml
    End
    Get ComGetXml Of hoPrivKey To sTemp1
    Get ComLoadXml Of hoPrivKeyXml sTemp1 To iSuccess

    // Get the modulus in base64 format:
    Get ComGetChildContent Of hoPrivKeyXml "Modulus" To sKeyModulus

    // --------------------------------------------------------------------------------
    // Now build the CSR using Chilkat's ASN.1 API.
    // The keyModulus will be embedded within the ASN.1.

    // A new ASN.1 object is automatically a SEQUENCE.
    // Given that the CSR's root item is a SEQUENCE, we can use
    // this as the root of our CSR.
    Get Create (RefClass(cComChilkatAsn)) To hoAsnRoot
    If (Not(IsComObjectCreated(hoAsnRoot))) Begin
        Send CreateComObject of hoAsnRoot
    End

    // Beneath the root, we have a SEQUENCE (the certificate request info), 
    // another SEQUENCE (the algorithm identifier), and a BITSTRING (the signature data)

    Get ComAppendSequence Of hoAsnRoot To iSuccess
    Get ComAppendSequence Of hoAsnRoot To iSuccess

    // ----------------------------------
    // Build the Certificate Request Info
    // ----------------------------------
    Get ComGetSubItem Of hoAsnRoot 0 To vAsnCertReqInfo
    If (IsComObject(vAsnCertReqInfo)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnCertReqInfo
        Set pvComObject Of hoAsnCertReqInfo To vAsnCertReqInfo
    End
    Get ComAppendInt Of hoAsnCertReqInfo 0 To iSuccess

    // Build the Subject part of the Certificate Request Info
    Get ComAppendSequenceR Of hoAsnCertReqInfo To vAsnCertSubject
    If (IsComObject(vAsnCertSubject)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnCertSubject
        Set pvComObject Of hoAsnCertSubject To vAsnCertSubject
    End

    // Add each subject part..
    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    // AppendSequence2 updates the internal reference to the newly appended SEQUENCE.
    // The OID and printable string are added to the SEQUENCE.
    Get ComAppendOid Of hoAsnTemp "2.5.4.6" To iSuccess
    Get ComAppendString Of hoAsnTemp "printable" "US" To iSuccess
    Send Destroy of hoAsnTemp

    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    Get ComAppendOid Of hoAsnTemp "2.5.4.8" To iSuccess
    Get ComAppendString Of hoAsnTemp "utf8" "Utah" To iSuccess
    Send Destroy of hoAsnTemp

    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    Get ComAppendOid Of hoAsnTemp "2.5.4.7" To iSuccess
    Get ComAppendString Of hoAsnTemp "utf8" "Lindon" To iSuccess
    Send Destroy of hoAsnTemp

    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    Get ComAppendOid Of hoAsnTemp "2.5.4.10" To iSuccess
    Get ComAppendString Of hoAsnTemp "utf8" "DigiCert Inc." To iSuccess
    Send Destroy of hoAsnTemp

    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    Get ComAppendOid Of hoAsnTemp "2.5.4.11" To iSuccess
    Get ComAppendString Of hoAsnTemp "utf8" "DigiCert" To iSuccess
    Send Destroy of hoAsnTemp

    Get ComAppendSetR Of hoAsnCertSubject To vAsnTemp
    If (IsComObject(vAsnTemp)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnTemp
        Set pvComObject Of hoAsnTemp To vAsnTemp
    End
    Get ComAppendSequence2 Of hoAsnTemp To iSuccess
    Get ComAppendOid Of hoAsnTemp "2.5.4.3" To iSuccess
    Get ComAppendString Of hoAsnTemp "utf8" "example.digicert.com" To iSuccess
    Send Destroy of hoAsnTemp

    Send Destroy of hoAsnCertSubject

    // Build the Public Key Info part of the Certificate Request Info
    Get ComAppendSequenceR Of hoAsnCertReqInfo To vAsnPubKeyInfo
    If (IsComObject(vAsnPubKeyInfo)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnPubKeyInfo
        Set pvComObject Of hoAsnPubKeyInfo To vAsnPubKeyInfo
    End

    Get ComAppendSequenceR Of hoAsnPubKeyInfo To vAsnPubKeyAlgId
    If (IsComObject(vAsnPubKeyAlgId)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnPubKeyAlgId
        Set pvComObject Of hoAsnPubKeyAlgId To vAsnPubKeyAlgId
    End
    Get ComAppendOid Of hoAsnPubKeyAlgId "1.2.840.113549.1.1.1" To iSuccess
    Get ComAppendNull Of hoAsnPubKeyAlgId To iSuccess
    Send Destroy of hoAsnPubKeyAlgId

    // The public key itself is a BIT STRING, but the bit string is composed of ASN.1
    // for the RSA public key.  We'll first build the RSA ASN.1 for the public key
    // (containing the 2048 bit modulus and exponent), and encoded it to DER, and then add
    // the DER bytes as a BIT STRING (as a sub-item of asnPubKeyInfo)

    // This is already a SEQUENCE..
    Get Create (RefClass(cComChilkatAsn)) To hoAsnRsaKey
    If (Not(IsComObjectCreated(hoAsnRsaKey))) Begin
        Send CreateComObject of hoAsnRsaKey
    End

    // The RSA modulus is a big integer.
    Get ComAppendBigInt Of hoAsnRsaKey sKeyModulus "base64" To iSuccess
    Get ComAppendInt Of hoAsnRsaKey 65537 To iSuccess

    Get ComGetEncodedDer Of hoAsnRsaKey "base64" To sRsaKeyDerBase64

    // Now add the RSA key DER as a BIT STRING.
    Get ComAppendBits Of hoAsnPubKeyInfo sRsaKeyDerBase64 "base64" To iSuccess
    Send Destroy of hoAsnPubKeyInfo

    // The last part of the certificate request info is an empty context-specific constructed item
    // with a tag equal to 0.
    Get ComAppendContextConstructed Of hoAsnCertReqInfo 0 To iSuccess

    // Get the DER of the asnCertReqInfo.  
    // This will be signed using the RSA private key.
    Get Create (RefClass(cComChilkatBinData)) To hoBdDer
    If (Not(IsComObjectCreated(hoBdDer))) Begin
        Send CreateComObject of hoBdDer
    End
    Get pvComObject of hoBdDer to vBdDer
    Get ComWriteBd Of hoAsnCertReqInfo vBdDer To iSuccess

    // Add the signature to the ASN.1
    Get Create (RefClass(cComChilkatBinData)) To hoBdSig
    If (Not(IsComObjectCreated(hoBdSig))) Begin
        Send CreateComObject of hoBdSig
    End
    Get pvComObject of hoBdDer to vBdDer
    Get pvComObject of hoBdSig to vBdSig
    Get ComSignBd Of hoRsa vBdDer "SHA1" vBdSig To iSuccess
    Get ComGetEncoded Of hoBdSig "base64" To sTemp1
    Get ComAppendBits Of hoAsnRoot sTemp1 "base64" To iSuccess

    Send Destroy of hoAsnCertReqInfo

    // ----------------------------------
    // Finally, add the algorithm identifier, which is the 2nd sub-item under the root.
    // ----------------------------------
    Get ComGetSubItem Of hoAsnRoot 1 To vAsnAlgId
    If (IsComObject(vAsnAlgId)) Begin
        Get Create (RefClass(cComChilkatAsn)) To hoAsnAlgId
        Set pvComObject Of hoAsnAlgId To vAsnAlgId
    End
    Get ComAppendOid Of hoAsnAlgId "1.2.840.113549.1.1.5" To iSuccess
    Get ComAppendNull Of hoAsnAlgId To iSuccess
    Send Destroy of hoAsnAlgId

    // Write the CSR to a DER encoded binary file:
    Get ComWriteBinaryDer Of hoAsnRoot "qa_output/mydomain.csr" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoAsnRoot To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // It is also possible to get the CSR in base64 format:
    Get ComGetEncodedDer Of hoAsnRoot "base64" To sCsrBase64

    Showln "Base64 CSR:"
    Showln sCsrBase64


End_Procedure