Verify and Unwrap PCKS7 Signed MIME

Demonstrates calling the Verify method to verify and unwrap PKCS7 signed MIME. The MIME is restored to the original structure that it would have originally had prior to signing. The Verify method works with both detached signatures, as well as opaque/attached signatures.

Download Chilkat MIME ActiveX

CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @mime int
    EXEC @hr = sp_OACreate 'Chilkat.Mime', @mime OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @success int

    EXEC sp_OAMethod @mime, 'UnlockComponent', @success OUT, 'Anything for 30-day trial'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mime, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    --  A PKCS7 signature usually embeds both the signing
    --  certificate with its public key.  Therefore, it is usually
    --  possible to verify a signature without the need to
    --  already have the certificate installed.

    --  Load the signed MIME from a file...
    EXEC sp_OAMethod @mime, 'LoadMimeFile', @success OUT, 'signedMime.txt'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mime, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    --  Verify the signed MIME and restore the MIME
    --  to the structure/content it had prior to signing.
    DECLARE @verified int

    EXEC sp_OAMethod @mime, 'Verify', @verified OUT
    IF @verified = 0
      BEGIN
        EXEC sp_OAGetProperty @mime, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    --  Examine the MIME after signature verification (i.e. "unwrapping")
    EXEC sp_OAMethod @mime, 'GetMime', @sTmp0 OUT
    PRINT @sTmp0


END
GO