(SQL Server) Extract a File from a .p7m (PKCS7 Signed-Data)

SQL Server example to extract the original file from a .p7m (Signed-Data PKCS7 Format) The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Download Chilkat Crypt ActiveX

CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @crypt int
    EXEC @hr = sp_OACreate 'Chilkat.Crypt2', @crypt OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    --  Any string argument automatically begins the 30-day trial.
    DECLARE @success int

    EXEC sp_OAMethod @crypt, 'UnlockComponent', @success OUT, '30-day trial'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    DECLARE @outFile nvarchar(4000)

    SELECT @outFile = '/Users/chilkat/testData/pdf/sample.pdf'
    DECLARE @inFile nvarchar(4000)

    SELECT @inFile = '/Users/chilkat/testData/p7m/sample.pdf.p7m'

    --  Verify and restore the original file:
    EXEC sp_OAMethod @crypt, 'VerifyP7M', @success OUT, @inFile, @outFile
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT

        PRINT @sTmp0
        RETURN
      END

    PRINT 'Success!'
END
GO