DataFlex

Check for an S/MIME Signing Time

Demonstrates the Chilkat Mime.HasSignatureSigningTime method, which returns whether the signer at a zero-based index included a CMS signingTime signed attribute. The only argument is the signer index; use NumSignerCerts for the count.

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: A signing time records when the signer claims to have signed, which matters for auditing and for validating a certificate that has since expired. It is an optional signed attribute, so not every signature has one — this predicate lets you check before calling GetSignatureSigningTimeStr, avoiding an error for signers that omitted it. Being a signed attribute, it is covered by the signature and cannot be altered undetected.

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DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoMime
    Integer n
    Integer i
    String sTemp1
    Boolean bTemp1

    Move False To iSuccess

    Get Create (RefClass(cComChilkatMime)) To hoMime
    If (Not(IsComObjectCreated(hoMime))) Begin
        Send CreateComObject of hoMime
    End
    Get ComLoadMimeFile Of hoMime "qa_data/signed.eml" To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoMime To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    //  After verifying, check whether each signer included a CMS signingTime signed attribute.  The
    //  only argument is the zero-based signer index.
    Get ComVerify Of hoMime To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoMime To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComNumSignerCerts Of hoMime To n

    For i From 0 To (n - 1)
        Get ComHasSignatureSigningTime Of hoMime i To bTemp1
        If (bTemp1) Begin
            Showln "Signer " i " included a signing time."
        End
        Else Begin
            Showln "Signer " i " did not include a signing time."
        End

    Loop



End_Procedure