> Earlier post seems to have been eaten, possibly by something expecting
> only subscribed addresses to post? Apologies for the resend if the
> original shows up within minutes...
>
> -----Forwarded Message-----
>
> From: Mikolaj Habryn <[EMAIL PROTECTED]>
> To: [EMAIL PROTECTED]
> Subject: vanishing attribute namespace prefixes
> Date: 12 Sep 2004 22:37:31 +1000
>
> Hi all - I have a feeling that this is a FAQ, but despite looking long
> and hard I haven't managed to find an answer.
>
> I'm generating a signature to cover a document that starts like so:
>
> <?xml version="1.0" encoding="UTF-8"?>
> <solicitation xmlns="urn:frog" Id="solicitation-0"
> xmlns:NS1="http://www.w3.org/2001/XMLSchema-instance";
> NS1:schemaLocation="urn:frog http://xml.rcpt.to/mikolaj/default";>
> <DNS xmlns="urn:frog">www.rcpt.to</DNS>
> ...
>
> The c14n'd version, as extracted by getSignedContentItem, looks like
> this:
>
> <solicitation Id="solicitation-0" schemaLocation="urn:frog
> http://xml.rcpt.to/mikolaj/default";><DNS>www.rcpt.to</DNS>
>
> Point of major annoyance:
> schemaLocation has lost its namespace! Needless to say, it turns the
> signed document into so much garbage. Why does this happen, and how do I
> fix it? I've tried playing with exclusive c14n and explicit namespaces,
> but it doesn't seem to actually make any difference. Is this an
> exclusive namespaces problem or something else entirely? Code is:
>
> Transforms t = new Transforms(thisDocument);
> HashSet hs = new HashSet();
> hs.add("xmlns:NS1");
> InclusiveNamespaces in = new InclusiveNamespaces(thisDocument, hs);
> in.setXPathNamespaceContext("NS1","http://www.w3.org/2001/XMLSchema-instance";);
> HelperNodeList names = new HelperNodeList();
> names.appendChild(in.getElement());
> t.addTransform(Transforms.TRANSFORM_ENVELOPED_SIGNATURE);
> t.addTransform(InclusiveNamespaces.ExclusiveCanonicalizationNamespace,names);
> XMLSignature sig = new XMLSignature(thisDocument, "http://frog/";,
> XMLSignature.ALGO_ID_SIGNATURE_DSA,
> Canonicalizer.ALGO_ID_C14N_EXCL_OMIT_COMMENTS);
>
> ...and results in...
>
> <ds:SignedInfo xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#";>
> <ds:CanonicalizationMethod
> Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#";
> xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"/>
> <ds:SignatureMethod
> Algorithm="http://www.w3.org/2000/09/xmldsig#dsa-sha1";
> xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"/>
> <ds:Reference URI="#solicitation-0" xmlns=""
> xmlns:ds="http://www.w3.org/2000/09/xmldsig#";>
> <ds:Transforms xmlns=""
> xmlns:ds="http://www.w3.org/2000/09/xmldsig#";>
> <ds:Transform
> Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature";
> xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"/>
> <ds:Transform
> Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#";
> xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#";>
> <ec:InclusiveNamespaces PrefixList="NS1"
> xmlns=""
> xmlns:NS1="http://www.w3.org/2001/XMLSchema-instance";
> xmlns:ds="http://www.w3.org/2000/09/xmldsig#";
> xmlns:ec="http://www.w3.org/2001/10/xml-exc-c14n#"/>
> </ds:Transform>
> </ds:Transforms>
> <ds:DigestMethod
> Algorithm="http://www.w3.org/2000/09/xmldsig#sha1";
> xmlns="" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"/>
> <ds:DigestValue xmlns=""
> xmlns:ds="http://www.w3.org/2000/09/xmldsig#";>iQbraueElJ+fAIDV6uoyWRcGkwc=</ds:DigestValue>
> </ds:Reference>
> </ds:SignedInfo>
>
> Point of minor annoyance:
> The namespace declaration has vanished. My workaround for this is to use
> the same sequence as in the XMLSignature code, namely to explicitly
> create an element with a tag of "prefix:solicitation" and to manually
> create "xmlns:prefix" attributes on the root element. I idly wonder why
> it should be necessary to do this, however, given that createElementNS
> is theoretically creating an element in a namespace (right?) which I
> would have imagined would have made everything just work. *handwave* Why
> doesn't it?
>
> m.
>
>
It seems to me that you are DOM tree does not represent what you think:
The output you have generated (the one with NS1) have done via the apache
writter and it have created the NS1 namespace and binding but in the DOM
tree doesn't exits. I recomend that when you create the DOM tree and add
your attirbutes use
rootElement.setAttributeNS("http://www.w3.org/2001/XMLSchema-instance","NS1:schemaLocation","urn:frog
http://xml.rcpt.to/mikolaj/default";);
rootElement.setAttributeNS(XMLNS_URI,"xmlns:NS1","http://www.w3.org/2001/XMLSchema-instance";);
I think your problems will be vanished.
Regards,
Raul,
http://r-bg.com
