SQL Server

Verify XML Digital Signature

See more XML Digital Signatures Examples

Verifies XML signatures in an XML file. 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
    DECLARE @iTmp0 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 requires the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

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

    EXEC sp_OAMethod @sbXml, 'LoadFile', @success OUT, 'qa_data/xml_dsig_verify/csioz_sample.xml', 'utf-8'
    IF @success <> 1
      BEGIN

        PRINT 'Failed to load XML file.'
        EXEC @hr = sp_OADestroy @sbXml
        RETURN
      END

    DECLARE @dsig int
    EXEC @hr = sp_OACreate 'Chilkat.XmlDSig', @dsig OUT

    -- First load the XML containing the signatures to be verified.
    EXEC sp_OAMethod @dsig, 'LoadSignatureSb', @success OUT, @sbXml
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @dsig, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @sbXml
        EXEC @hr = sp_OADestroy @dsig
        RETURN
      END

    -- It's possible that an XML document can contain multiple signatures.
    -- Each can be verified as follows:
    DECLARE @i int
    SELECT @i = 0
    EXEC sp_OAGetProperty @dsig, 'NumSignatures', @iTmp0 OUT
    WHILE @i < @iTmp0
      BEGIN
        -- Select the Nth signature by setting the Selector property.
        EXEC sp_OASetProperty @dsig, 'Selector', @i

        -- The bVerifyReferenceDigests argument determines if we want
        -- to also verify each reference digest.  If set to 0,
        -- then only the SignedInfo part of the Signature is verified.
        DECLARE @bVerifyReferenceDigests int
        SELECT @bVerifyReferenceDigests = 1
        DECLARE @bVerified int
        EXEC sp_OAMethod @dsig, 'VerifySignature', @bVerified OUT, @bVerifyReferenceDigests


        PRINT 'Signature ' + @i + 1 + ' verified = ' + @bVerified

        SELECT @i = @i + 1
      END

    EXEC @hr = sp_OADestroy @sbXml
    EXEC @hr = sp_OADestroy @dsig


END
GO