SQL Server

Create XML Digital Signature using a ECDSA Key

See more XML Digital Signatures Examples

Demonstrates how to create an XML digital signature using a ECDSA key.

This example requires Chilkat v9.5.0.69 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
    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.

    --  The SOAP XML to be signed in this example contains the following:

    --  <?xml version="1.0" encoding="UTF-8" standalone="no" ?>
    --  <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
    --      <SOAP-ENV:Header>
    --          <wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" SOAP-ENV:mustUnderstand="1"></wsse:Security>
    --      </SOAP-ENV:Header>
    --      <SOAP-ENV:Body xmlns:SOAP-SEC="http://schemas.xmlsoap.org/soap/security/2000-12" SOAP-SEC:id="Body">
    --          <z:FooBar xmlns:z="http://example.com" />
    --      </SOAP-ENV:Body>
    --  </SOAP-ENV:Envelope>
    --  

    --  The above XML is available at https://www.chilkatsoft.com/exampleData/soapToSign.xml
    --  Fetch the XML and then sign it..

    DECLARE @url nvarchar(4000)
    SELECT @url = 'https://www.chilkatsoft.com/exampleData/soapToSign.xml'
    DECLARE @http int
    EXEC @hr = sp_OACreate 'Chilkat.Http', @http OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    DECLARE @sbSoapXml int
    EXEC @hr = sp_OACreate 'Chilkat.StringBuilder', @sbSoapXml OUT

    EXEC sp_OAMethod @http, 'QuickGetSb', @success OUT, @url, @sbSoapXml
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @http, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @sbSoapXml
        RETURN
      END

    --  This example uses an ECDSA private key for signing.  
    --  There are many ways to load an ECDSA private key using Chilkat.  This example
    --  will load from an unencrypted PEM file.

    --  For your convenience, Chilkat put this sample ECDSA PEM here:  https://www.chilkatsoft.com/exampleData/secp256r1-key.zip
    DECLARE @ecKey int
    EXEC @hr = sp_OACreate 'Chilkat.PrivateKey', @ecKey OUT

    EXEC sp_OAMethod @ecKey, 'LoadPemFile', @success OUT, 'qa_data/ecc/secp256r1-key.pem'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ecKey, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @sbSoapXml
        EXEC @hr = sp_OADestroy @ecKey
        RETURN
      END

    --  To create the XML digital signature (i.e. embed the signature within
    --  the SOAP XML), we specify what is desired, and then call the method to 
    --  create the XML signature.
    --  
    --  For example, the application must provide the following:
    --      - Where to put the signature.
    --      - What to sign.
    --      - The algorithms to be used.
    --      - The key to be used for signing.
    --  

    DECLARE @xmlSigGen int
    EXEC @hr = sp_OACreate 'Chilkat.XmlDSigGen', @xmlSigGen OUT

    --  In this example, the Signature will be placed within the wsse:Security element.
    --  To specify the location, set the SigLocation property to the XML path to this element,
    --  using vertical bar characters to separate tags.
    EXEC sp_OASetProperty @xmlSigGen, 'SigLocation', 'SOAP-ENV:Envelope|SOAP-ENV:Header|wsse:Security'

    --  An XML digital signature contains one or more references.  A given reference
    --  can be a same-document reference (to an XML fragment), or an external reference.
    --  This example will add a single same-document reference.  We'll add a reference to the XML fragment
    --  at SOAP-ENV:Body, which is indicated by providing the value of the "Id" attribute (where "Id" is case
    --  insensitive).  For each same-document reference, we must also indicate the hash algorithm and XML canonicalization
    --  algorithm to be used.  For this example we'll choose SHA-256 and Exclusive XML Canonicalization.
    EXEC sp_OAMethod @xmlSigGen, 'AddSameDocRef', @success OUT, 'Body', 'sha256', 'EXCL_C14N', '', ''

    --  Let's provide the ECDSA key to be used for signing:
    EXEC sp_OAMethod @xmlSigGen, 'SetPrivateKey', @success OUT, @ecKey

    --  We're leaving the following properties at their default values:
    --  
    --     - SigNamespacePrefix (default is "ds")
    --     - SignedInfoCanonAlg  (default is EXCL_C14N)
    --     - SignedInfoDigestMethod (default is sha256)
    --     - KeyInfoType (default is "KeyValue", where the ECDSA public key is included in the Signature)

    --  Note: Each Reference specifies its own algorithms for XML canonicalization and hashing.
    --  The SignedInfo part also has specified hash and canonicalization algorithms, which may be different
    --  than the algorithms used in the References.
    --  In this example, we use Exclusive XML Canonicalization and SHA-256 throughout.

    --  Finally, we're going to set one property that's optional, but commonly used.
    --  It's the SignedInfoPrefixList.  In this case, we're using Exclusive Canonicalization, and the signature
    --  will be placed in a location within the XML document where namespace prefixes are used in the ancestors.
    --  Specifically, the "wsse" and "SOAP-ENV" namespace prefixes are used.
    EXEC sp_OASetProperty @xmlSigGen, 'SignedInfoPrefixList', 'wsse SOAP-ENV'

    --  OK, everything's specified, so let's create the XML digital signature:
    --  This in-place signs the XML.  If successful, sbSoapXml will contain the 
    --  XML with the digital signature at the specified location.
    EXEC sp_OAMethod @xmlSigGen, 'CreateXmlDSigSb', @success OUT, @sbSoapXml
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @xmlSigGen, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @sbSoapXml
        EXEC @hr = sp_OADestroy @ecKey
        EXEC @hr = sp_OADestroy @xmlSigGen
        RETURN
      END

    --  Examine the signed SOAP XML:
    EXEC sp_OAMethod @sbSoapXml, 'GetAsString', @sTmp0 OUT
    PRINT @sTmp0

    --  This is the signed SOAP XML.
    --  Chilkat emits the Signature in compact form on a single line.  Whitespace in XML signatures
    --  matters.  Chilkat's opinion is that writing the Signature without whitespace minimizes the chance
    --  for problems with whatever software might be verifying the signature.

    --  <?xml version="1.0" encoding="UTF-8" standalone="no" ?>
    --  <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
    --      <SOAP-ENV:Header>
    --          <wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" SOAP-ENV:mustUnderstand="1"><ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#"><ds:SignedInfo><ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"><InclusiveNamespaces xmlns="http://www.w3.org/2001/10/xml-exc-c14n#" PrefixList="wsse SOAP-ENV"/></ds:CanonicalizationMethod><ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha256"/><ds:Reference URI="#Body"><ds:Transforms><ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/></ds:Transforms><ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/><ds:DigestValue>OwgHPZNfDkXnZsjpfzXqAcT3RV3HzmTsEy2bP44FJ0M=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>jmPSGgtirHSjjcs/o0NIDwwvy4aFBCEosSN+XP5NLVuGpRYnS2EM7mItiw6TKmESAoJYV23ZN4pZ9BFRKSvZqw==</ds:SignatureValue><ds:KeyInfo><ds:KeyValue><ds:ECKeyValue xmlns="http://www.w3.org/2009/xmldsig11#"><ds:NamedCurve URI="urn:oid:1.2.840.10045.3.1.7" /><ds:PublicKey>BOVKaiLPKEDChhkA64UEBOXTv/VFHnhrUPN+bXqCvEl7rroAYpH5tKzbiGTtMSlp4JO9Pxg44zeX7EoWDvOrpD0=</ds:PublicKey></ds:ECKeyValue></ds:KeyValue></ds:KeyInfo></ds:Signature></wsse:Security>
    --      </SOAP-ENV:Header>
    --      <SOAP-ENV:Body xmlns:SOAP-SEC="http://schemas.xmlsoap.org/soap/security/2000-12" SOAP-SEC:id="Body">
    --          <z:FooBar xmlns:z="http://example.com" />
    --      </SOAP-ENV:Body>
    --  </SOAP-ENV:Envelope>

    --  The above signed XML contains the ECDSA public key in the ECKeyValue fragment (within the ds:KeyInfo).
    --  The signature can easily be verified like this:

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

    --  First load the XML containing the signature(s) to be verified.
    EXEC sp_OAMethod @verifier, 'LoadSignatureSb', @success OUT, @sbSoapXml
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @verifier, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @http
        EXEC @hr = sp_OADestroy @sbSoapXml
        EXEC @hr = sp_OADestroy @ecKey
        EXEC @hr = sp_OADestroy @xmlSigGen
        EXEC @hr = sp_OADestroy @verifier
        RETURN
      END

    DECLARE @bVerified int
    EXEC sp_OAMethod @verifier, 'VerifySignature', @bVerified OUT, 1
    IF @bVerified <> 1
      BEGIN
        EXEC sp_OAGetProperty @verifier, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
      END

    PRINT 'Signature verified = ' + @bVerified

    EXEC @hr = sp_OADestroy @http
    EXEC @hr = sp_OADestroy @sbSoapXml
    EXEC @hr = sp_OADestroy @ecKey
    EXEC @hr = sp_OADestroy @xmlSigGen
    EXEC @hr = sp_OADestroy @verifier


END
GO