PureBasic

Verify XML Signature having KeyInfo / X509Data / X509Certificate

See more XML Digital Signatures Examples

This example demonstrates how to verify an XML Digital Signature where the KeyInfo element contains an X509Data element, which in turn contains an X509Certificate element which contains the base64-encoded certificate. PureBasic

IncludeFile "CkHttp.pb"
IncludeFile "CkStringBuilder.pb"
IncludeFile "CkXmlDSig.pb"

Procedure ChilkatExample()

    success.i = 0

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

    ; The SOAP XML with digital signature verified in this example is available at 
    ; https://www.chilkatsoft.com/exampleData/sigWithX509Certificate.xml

    signedSoapXmlUrl.s = "https://www.chilkatsoft.com/exampleData/sigWithX509Certificate.xml"

    ; First, let's get the signed SOAP XML..
    http.i = CkHttp::ckCreate()
    If http.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    sbXml.i = CkStringBuilder::ckCreate()
    If sbXml.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkHttp::ckQuickGetSb(http,signedSoapXmlUrl,sbXml)
    If success <> 1
        Debug CkHttp::ckLastErrorText(http)
        CkHttp::ckDispose(http)
        CkStringBuilder::ckDispose(sbXml)
        ProcedureReturn
    EndIf

    ; The signed XML downloaded from the above URL contains the following.
    ; Note: Everything we need to verify the signature is already available within the signed XML.
    ; The KeyInfo part of the Signature contains the X.509 certificate in base64 format,
    ; and the public key used to verify the signature is contained within the X.509.
    ; Chilkat automatically fetches and uses the public key from the base64 certificate.
    ; 

    ; <?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#rsa-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/2000/09/xmldsig#sha1"/><ds:DigestValue>PIiVPpuMc1jGpWaL8ftzTOcc4gc=</ds:DigestValue></ds:Reference></ds:SignedInfo><ds:SignatureValue>dlSGYRtxv8DiGQ9THPEdPTlbwjkidCUEutVWkqhnjzKOxjl6EZPp6ibf7ogrn1QJAabo7eb/d2UjD8LXzQYB+q9OmN29dsDcg4i9hzpttjU9xt8Sc3IgdaQ+6NXStWd1AKrjNTCY52sOpIWh45uff/yjf9ynsbCo/UR8+hk6ZDCrM78YEyMj52miXzVQtSZ7f+bvWtz8iPppXXC+/zwGPAI9EPC+9uRHRRh4vzGwid+clMmh9FF/0Oe4n0G5dBZvwLPncwOMg0UxLVs63ZRdTCSku4oKReQieqNr7+hzBAKaS8NRpxMtx2XC5aR0wYMkYT9API/vYubeU0L3r4lplw==</ds:SignatureValue><ds:KeyInfo><ds:X509Data><ds:X509Certificate>MIIDgzCCAmugAwIBAgIBADANBgkqhkiG9w0BAQUFADBcMRUwEwYDVQQDDAxUZXN0IENvbXBhbnkxCzAJBgNVBAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcNMTcwOTEzMDA1NTM1WhcNMTgwOTEzMDA1NTM1WjBcMRUwEwYDVQQDDAxUZXN0IENvbXBhbnkxCzAJBgNVBAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDiWRKlx+88u4SKZnfCMraqMsfJCs6tcz3EjMYTWmRKhhUOE9pDkvZfv0mgF7pNHsTKvFRtoVnEVQaZC5TlHNOGa2QWit9YuruWjW8VSaU4s9gR1/Cg9/Zc8Z0yUEDpsaVnwuoARpVzvzoRzPmTNpMNEcQ07aBjHP7OJrwyvcdqQA1BbfDVMmRmw1d+/i8tyR3cTyzl/3TismN5nrmhGh/ZF75FFA/xDN7PbVYDPowiFnEVHiBrYh2mFTabRUnb7K4oLx+d1L5x3Az299F/HYZlBenXpJLtnCL3+HY6qsGXVbzKjlKNqbXsmlzVkChu093weN/qUvWO2883cEiXmdqxAgMBAAGjUDBOMB0GA1UdDgQWBBRsMy2bxsCKYyUYtTYz/zZbz7Le0zAfBgNVHSMEGDAWgBRsMy2bxsCKYyUYtTYz/zZbz7Le0zAMBgNVHRMEBTADAQH/MA0GCSqGSIb3DQEBBQUAA4IBAQBnFQ+Sc3s8y79DTsA7CvvAFeG/zvWQiu8yUM5LO1QcWeQQj29GMThqrY21dNfkynl7mZUMEeXKvwwzweFCc2odiUPHxoV1G4FEtzNaZ8Ap9jye78YQ8SB8NPQwC7ovecfSqNflT4NMAThSuxpGp8Ugf7a24LXozLzLbCRvG9sLGyRneZbfU8B43ELRLCkjzWR32N7D2pmKk4CEMiW0ScphU1JEHaimneMaTFc63hNzKpuj7+BGv4ZuvB1j/Mbmz53PGgFKnGQHPb2TIvMxyB+lML5vE0Bm8YWtP8DNyx11CCCdBdMWfeta6MjmmqcV5/YEq92c5O2Ql94tWFNLR6wQ</ds:X509Certificate></ds:X509Data></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>

    ; To verify this signature, we simply load and verify:
    verifier.i = CkXmlDSig::ckCreate()
    If verifier.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkXmlDSig::ckLoadSignatureSb(verifier,sbXml)
    If success <> 1
        Debug CkXmlDSig::ckLastErrorText(verifier)
        CkHttp::ckDispose(http)
        CkStringBuilder::ckDispose(sbXml)
        CkXmlDSig::ckDispose(verifier)
        ProcedureReturn
    EndIf

    bVerified.i = CkXmlDSig::ckVerifySignature(verifier,1)
    If bVerified <> 1
        Debug CkXmlDSig::ckLastErrorText(verifier)
        CkHttp::ckDispose(http)
        CkStringBuilder::ckDispose(sbXml)
        CkXmlDSig::ckDispose(verifier)
        ProcedureReturn
    EndIf

    Debug "Signature verified!"


    CkHttp::ckDispose(http)
    CkStringBuilder::ckDispose(sbXml)
    CkXmlDSig::ckDispose(verifier)


    ProcedureReturn
EndProcedure