SQL Server

Create CMS Signed File (PDF) with Multiple Signing Certificates

See more Digital Signatures Examples

Demonstrates how to sign a file by adding multiple signatures (multiple certificates). This example signs a PDF file to produce an output file that is a CMS signature wrapping the original PDF. (Note: This is different than modifying a PDF by injecting a signature into the PDF file format.)

Note: This example requires Chilkat v9.5.0.83 or greater.

SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

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

    DECLARE @crypt int
    EXEC @hr = sp_OACreate 'Chilkat.Crypt2', @crypt OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- ------------ This example requires Chilkat v9.5.0.83 or greater.

    DECLARE @cert1 int
    EXEC @hr = sp_OACreate 'Chilkat.Cert', @cert1 OUT

    EXEC sp_OAMethod @cert1, 'LoadPfxFile', @success OUT, 'qa_data/pfx/cert_test123.pfx', 'test123'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @cert1, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        RETURN
      END

    DECLARE @cert2 int
    EXEC @hr = sp_OACreate 'Chilkat.Cert', @cert2 OUT

    EXEC sp_OAMethod @cert2, 'LoadPfxFile', @success OUT, 'qa_data/pfx/test_secret.pfx', 'secret'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @cert2, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        EXEC @hr = sp_OADestroy @cert2
        RETURN
      END

    -- ------------ This example requires Chilkat v9.5.0.83 or greater.

    -- Tell the crypt component to use both certificates for signing. 
    -- When we create the signature, it will be signed by both certificates.
    EXEC sp_OAMethod @crypt, 'AddSigningCert', @success OUT, @cert1
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        EXEC @hr = sp_OADestroy @cert2
        RETURN
      END
    EXEC sp_OAMethod @crypt, 'AddSigningCert', @success OUT, @cert2
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        EXEC @hr = sp_OADestroy @cert2
        RETURN
      END

    -- The CadesEnabled property applies to all methods that create PKCS7 signatures. 
    -- To create a CAdES-BES signature, set this property equal to true. 
    EXEC sp_OASetProperty @crypt, 'CadesEnabled', 1

    EXEC sp_OASetProperty @crypt, 'HashAlgorithm', 'sha256'

    -- We can sign any type of file, creating a .p7s as output.
    -- The .p7s contains the signature and also embeds the data of the file that is signed.
    DECLARE @inFile nvarchar(4000)
    SELECT @inFile = 'qa_data/pdf/sample.pdf'
    DECLARE @p7sFile nvarchar(4000)
    SELECT @p7sFile = 'qa_output/sample.pdf.p7s'

    -- Create the CAdES-BES attached signature, which contains the original data.
    -- Note: Chilkat's function naming is not accurate.  CreateP7M creates a PKCS7 signature where the signed file
    -- is contained within the signature.  CreateP7S creates a detached PKCS7 signature where the signed file
    -- is NOT contained within the signature.  We want the data to be contained in the signature, therefore
    -- we call CreateP7M even though we are naming our output file .p7s.
    EXEC sp_OAMethod @crypt, 'CreateP7M', @success OUT, @inFile, @p7sFile
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        EXEC @hr = sp_OADestroy @cert2
        RETURN
      END

    -- Verify the .p7s file and extract the original file from the .p7s. 
    DECLARE @extractedToFilePath nvarchar(4000)
    SELECT @extractedToFilePath = 'qa_output/sample.pdf'
    EXEC sp_OAMethod @crypt, 'VerifyP7M', @success OUT, @p7sFile, @extractedToFilePath
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @crypt, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @crypt
        EXEC @hr = sp_OADestroy @cert1
        EXEC @hr = sp_OADestroy @cert2
        RETURN
      END


    PRINT 'Success!'

    EXEC @hr = sp_OADestroy @crypt
    EXEC @hr = sp_OADestroy @cert1
    EXEC @hr = sp_OADestroy @cert2


END
GO