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DataFlex

Add a Detached Signature (Separate Key, Header Control)

See more MIME Examples

Demonstrates the Chilkat Mime.AddDetachedSignaturePk2 method, which creates a detached signature with a separately supplied certificate and private key, and a third argument controlling transfer of the existing message header fields to the new outer entity.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This combines the two variations — certificate and key supplied separately, plus explicit header placement — for the case that needs both. It is the most flexible of the detached-signature methods; choose it when your key material is separate and you also care about where the message headers end up on the signed result.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoMime
    Variant vCert
    Handle hoCert
    Variant vPrivKey
    Handle hoPrivKey
    Boolean iTransferHeaderFields
    String sTemp1

    Move False To iSuccess

    Get Create (RefClass(cComChilkatMime)) To hoMime
    If (Not(IsComObjectCreated(hoMime))) Begin
        Send CreateComObject of hoMime
    End
    Get ComSetBodyFromPlainText Of hoMime "This message will be signed." To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoMime To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Load the certificate and its private key separately.
    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End
    Get ComLoadFromFile Of hoCert "qa_data/signer.cer" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatPrivateKey)) To hoPrivKey
    If (Not(IsComObjectCreated(hoPrivKey))) Begin
        Send CreateComObject of hoPrivKey
    End
    Get ComLoadPemFile Of hoPrivKey "qa_data/signer_privkey.pem" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPrivKey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  Create a detached signature with separately supplied cert and private key, where the 3rd
    //  argument controls whether the existing message header fields are transferred to the new outer
    //  multipart/signed entity.
    Move True To iTransferHeaderFields
    Get pvComObject of hoCert to vCert
    Get pvComObject of hoPrivKey to vPrivKey
    Get ComAddDetachedSignaturePk2 Of hoMime vCert vPrivKey iTransferHeaderFields To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoMime To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComSaveMime Of hoMime "qa_output/signed.eml" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoMime To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "Detached signature added (headers transferred)."


End_Procedure