[2]This document specifies protocol bindings with
security characteristics for the XML
Key Management Specification (XKMS).
This section describes the status of this document at the time of its
publication. Other documents may supersede this document. A list of current
W3C publications and the latest revision of this technical report can be
found in the W3C technical reports index
at http://www.w3.org/TR/.
This is Part 2 of the W3C Candidate Recommendation for the XML Key
Management Specification (XKMS Version 2.0), made available for public review
by the XKMS Working
Group. Part 1 of this
specification covers the XKMS protocols and services. For background on this
work, please see the XKMS Activity Statement.
Note that when first released on 18 April 2003, the XKMS specification
consisted of two separate documents: XML
Key Management Specification Version 2.0 and XML Key Management
Specification Version 2.0 Bindings. In order to show their
relationship, the Working Group decided to now refer to them as Part-1 and
Part-2 of the XKMS Specification. This is just an Editorial modification and
doesn't concern the content of those documents.
This document is based upon the XKMS Bindings Version 2.0 Working
Draft of 18 April 2003 and feedback received during the review period
(see the Disposition
of Comments document). The XKMS Working Group believes that this
specification addresses its Requirements and
all of the Last Call issues.
The purpose of a W3C Candidate Recommendation is to gather implementation
experience. The status of implementations will be tracked on the XKMS Working Group page. The XKMS CR
period will last a minimum of six months (September 2004) to ensure that
enough time is given for providing implementation feedback. Note that the
Conformance Section of this document may be improved following the experience
gained during the CR period.
Patent disclosures relevant to this specification may be found on the
Working Group's patent
disclosure page in conformance with W3C policy.
Comments on this document should be sent to public-xkms-comments@w3.org, a mailing list with a public archive. General discussion of related technology is
welcome in www-xkms@w3.org
(archive).
Publication as a Candidate Recommendation does not imply endorsement by
the W3C Membership. This is a draft document and may be updated, replaced or
obsoleted by other documents at any time. It is inappropriate to cite this
document as other than work in progress.
XML Key Management
Specification (XKMS) Bindings
Version 2.0
W3C Working Draft 26th
August 2003
Abstract
Status of this
document
Table Of Contents
1 Introduction
1.1 Editorial and Conformance
Conventions
1.2 Acknowledgments
1.3 Definition of
Terms
1.4 Structure of this
documentt
2 Security Requirements
2.1 Confidentiality
2.2 Request
Authentication
2.3 Response
Authentication
2.4 Persistent
Authentication
2.5 Message Correlation
(Response Replay and Request Substitution)
2.6 Request Replay
2.7 Denial of Service
2.8 Security Requirements
Summary
3 SOAP Binding
3.1 XKMS SOAP Message
Binding
3.2 Namespace
inclusions
3.3 Computation of XML
Signature Elements in XKMS Messages
3.4 Use of SOAP Faults
3.5 SOAP over HTTP
binding
4 Security Bindings
4.1 Payload Authentication
Binding
4.2 Secure Socket Layer and
Transaction Layer (SSL/TLS)Security Binding
Appendix A
References
Appendix B
Changes
1.1 Editorial and Conformance
Conventions
[8]This specification uses XML Schemas [XML-schema] to describe the content model.
[9]The key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
"OPTIONAL" in this specification are to be interpreted as described in [RFC2119]:
[10]"they MUST only be used where it is actually
required for interoperation or to limit behavior which has potential for
causing harm (e.g., limiting retransmissions)"
[11]Consequently, we use these capitalized keywords
to unambiguously specify requirements over protocol and application features
and behavior that affect the interoperability and security of
implementations. These key words are not used (capitalized) to describe XML
grammar; schema definitions unambiguously describe such requirements and we
wish to reserve the prominence of these terms for the natural language
descriptions of protocols and features. For instance, an XML attribute might
be described as being "optional." Compliance with the XML-namespace
specification [XML-NS] is described as
"REQUIRED."
[12]The contributions of the following Working
Group members to this specification are gratefully acknowledged in accordance
with the contributor
policies and the active WG roster.
- Daniel Ash, Identrus
- Blair Dillaway, Microsoft
- Donald Eastlake 3rd, Motorola
- Yassir Elley, Sun Microsystems
- Jeremy Epstein, webMethods
- Stephen Farrell, Baltimore(Co-Chair)
- Phillip Hallam-Baker, VeriSign Inc. (Editor)
- Loren Hart, VeriSign Inc.
- Mack Hicks, Bank of America
- Merlin Hughes, Baltimore
- Frederick Hirsch, Nokia Mobile Phones
- Mike Just, Treasury Board of Canada Secretariat
- Brian LaMacchia, Microsoft
- Pradeep Lamsal
- Shivaram Mysore, Sun Microsystems (Co-Chair)
- Joseph Reagle, W3C
- Dave Remy, GeoTrust, Inc.
- Peter Rostin, RSA Security Inc.
- Ed Simon, XMLsec Inc.
- Slava Galperin, Sun Microsystems
[13]The authors also acknowledge the extensive
assistance provided in the design stage of this specification by David Solo
(CitiGroup), and the contributions of Jeremy Epstein, (webMethods), Andrew
Layman (Microsoft), Dr Paul Boisen (NSA), Dan Guinan, Marc Hayes,
Alex Deacon, Mingliang Pei (VeriSign)..
[14]This document uses the terms defined in section 1.3 of part
one of this specification in the manner described therein.
[15]The remainder of this document describes the
XML Key Information Service Specification and XML Key Registration Service
Specification.
- Section 2: Security Requirements
- The security requirements of the XKMS protocol are specified.
- Section 3: Payload Security Protocol
- The security properties supported by the XKMS payload security
features are described.
- Section 4: Security Bindings
- The use of XKMS payload security features is described in the context
of specific security protocols.
- Section 5: Security Considerations
- Security considerations relevant to the implementation and deployment
of the specification are discussed.
[16]Security enhancements MAY be required to
control the following risks:
- Confidentiality
- Request Authentication
- Response Authentication
- Persistent Authentication
- Response Replay
- Request Substitution
- Request Replay
- Denial of Service
[17]The security enhancements required varies
according to the application. In the case of a free or un-metered service the
service may not require authentication of the request. A responder that
requires an authenticated request must know in that circumstance that the
request corresponds to the specified response.
[18]Message confidentiality protects protocol
messages from disclosure to third parties. Confidentiality MAY be a
requirement for an XKMS service. Deployments SHOULD consider the extent to
which the content of XKMS messages reveal sensitive information. A
confidentiality requirement MAY exist even if a service only provides
information from public sources as the contents of a request might disclose
information about the client.
[19]The use of transport or payload confidentiality
protection is NOT a substitute for the encryption of private keys specified
in the XKRSS Registration and Recovery services. A service that supports
registration of server generated keys or Key Recovery MUST implement the use
of XML Encryption with a strong cipher.
[20]An XKMS service SHOULD support Confidentiality
by means of encryption.
[21]The means by which the client determines that
the encryption key of the service is trustworthy is outside the scope of this
specification. Possible mechanisms include:
- A root key embedded in the client application
A trustworthy signing key exchanged using an XML based assertion
mechanism such as that proposed by[WS-TrustAxiom].- A signing key obtained using some other retrieval mechanism such as
PKIX [RFC3280] or SPKI [RFC2693].
[22]An XKMS service MAY determine the
trustworthiness of an encryption key by reference to another XKMS service
provided that the chain of references is eventually grounded by a mechanism
that establishes direct trust between the client and the service.
[23]Request Message Authentication MAY be required.
An XKMS Service MAY require request authentication in deployments where the
XKMS service is restricted to a specific audience, possibly as a paid
service. An XKMS Service MAY require request authentication in contexts where
different levels of service are supported according to the identity of the
requestor.
[24]In addition various forms of Authentication MAY
be required in the XKRSS Registration protocol to confirm the credentials of
the party initiating the request and their possession of the private key
component of the key pair(s) being registered.
[25]An XKMS service SHOULD support Message Request
Authentication.
[26]Message Response Authentication MAY be
required. Message Response Authentication is required in any deployment of a
Validate service. A Locate service that provides only data that is
self-authenticating such as X.509 or PGP certificates does not require
Message Response Authentication.
[27]Note that Message Response Authentication is
considered separately from Response Replay Protection.
[28]An XKMS service SHOULD support Request
Authentication.
[29]In some circumstances requests or responses or
to both may require persistent authentication. That is a message sent by A
and authenticated by B may be subject to forwarding and authentication by C.
In addition some applications may require further measures to ensure that
messages meet certain legal standards to prevent repudiation.
[30]An XKMS service MAY support Persistent
Authentication by means of a digital signature on the message.
[31]An XKMS service MUST support a means of
ensuring correct message correlation. That is the requestor must be assured
that the response returned was made in response to the intended request sent
to the service and not a modification of that request (Request Substitution
attack) or a response to an earlier request (response replay attack).
[32]In order to prevent response replay and request
message substitution attacks the requestor SHOULD ensure that the response
corresponds to the request. For correspondence verification to be possible
authentication of the response is required. In the TLS binding the
correspondence between the request and response is provided by the transport
layer. For message layer security mechanisms such as payload security the
mechanism required depends on whether or not the request is authenticated as
follows:
- Authenticated Request
- If the request and the response are authenticated the correspondence
of the request and response may be determined by verifying the value of
RequestId in the response.
- Digest Authenticated Request
- If the original request was authenticated by means of an XML
Signature with a message digest as the signing algorithm, the service
can still ensure a strong binding of the response to the original
request by means of the <RequestSignatureValue> element.
[33]An XKMS service may require protection against
a Request replay attack. In circumstances where no accounting or other
auditing is used to keep track of requests made, protection against a request
replay attack may not be required.
[34]An XKMS service MAY provide protection against
a Request Replay.
[35]An XKMS service may require protection against
a Denial of Service attack by means of protocol measures. Such measures may
not be required in circumstances where an XKMS service is protected against
Denial of Service by other means such as the service is managed on an
isolated, tightly controlled network and does not provide service outside
that network.
[36]Denial of service attacks that originate from a
single identified source or set of sources may be addressed by applying
velocity controls. In cases where the source of the denial of service is
disguised lightweight authentication techniques such as the two-phase
protocol described bellow may be used to detect requests from forged
addresses.
[37]An XKMS service SHOULD support protection
against a Denial of Service attack.
[38]The following table summarizes the possible
security requirements that an XKMS service deployment may be subject to:
| Security Issue |
Requirement |
Comments |
| Confidentiality |
Some |
The information provided by an XKMS
service may be confidential, the fact that a party has requested
particular information from an XKMS service may allow confidential
information to be deduced. Many XKMS applications do not require
confidentiality however. |
| Request Authentication |
Some |
A service only needs to authenticate a
request for information if either the information is confidential or
some form of charge is to be made for use of the service. |
| Response Authentication |
Most |
An XKMS service that provides only a
Location service for self authenticating key information such as
Digital Certificates does not require authentication. |
| Persistent Authentication |
Some |
Although some XKMS applications have a
specific requirement to support Non-Repudiation, the ability to
repudiate requests and responses is acceptable in many
applications. |
| Message Correspondence |
All |
The RequestId correspondence mechanism can
only be used if the Request Authentication mechanism can be relied
upon. Otherwise the Digest Mechanism should be used. |
| Request Replay |
Some |
Request replay attacks are likely to only
be a concern if the service charges on a per request basis or as a
type of Denial of Service attack. |
| Denial of Service |
Most |
Any service made available on a public
network is likely to be subject to a Denial of Service attack. The
risk of a Denial of Service attack is generally considered to be
reduced on closed networks such as internal enterprise networks. |
[39]Where the security requirements of the XKRSS
protocol differ from those of XKISS they are addressed by the XKRSS protocol
directly rather than relying upon the message security binding.
[40]For example the XKRSS registration functions
are designed to support use in modes in which a client registration request
is accepted by a Local Registration Authority and then forwarded to a Master
Registration Authority. In this mode it is essential that the proof of
possession of the private key being registered can be verified by both the
Local Registration Authority and the Master Registration Authority, even
though the authentication for the request sent to the Master Registration
Authority is likely to be provided by the Local Registration Authority,
rather than the original requestor. Similar considerations affect the
distribution of private keys..
| Security Issue |
Requirement |
Comments |
| Confidentiality of Private Key |
If Server Generated Key
pairs used |
If a Register service supports registration of server
generated key pairs or key recovery strong encryption of the private
key MUST be supported. |
| Registration Request Authentication |
Some |
XKMS Registration services SHOULD support the
authentication of registration requests for initial registration of a
key binding. Registration requests for secondary registration of
previously issued credentials (i.e. a signed key binding or a digital
certificate) MAY be permitted without authentication. |
| Registration Proof Of Possession |
Some |
XKMS Registration services SHOULD support the
verification of Proof Of Possession in the initial registration of
client generated keys. |
| Authentication by Revocation Code |
Some |
The XKMS Revocation code is self authenticating. |
[41]This section describes a mechanism for
communicating the XKMS messages defined in Part 1 of this specification using
the SOAP message protocol. XKMS implementers should support the SOAP message
protocol for interoperability. When doing do, they MUST use the binding
described herein. Bindings for both SOAP 1.2 [SOAP1.2-1][SOAP1.2-2] and SOAP
1.1[SOAP] protocols are specified.
[42]XKMS 2.0 implementations MUST support the use
of SOAP 1.2. For near term compatibility with existing tools and
infrastructure, SOAP 1.1 MAY be used
[43]XKMS implementers shall use SOAP document style
request-response messaging with the XKMS messages defined in Part 1 carried
as unencoded Body element content. The SOAP 1.2 RPC representation, and
requisite encoding style, are not used. The potential benefits of using the
RPC representation do not justify the additional effort required to define a
mapping from the Part 1 messages to an appropriate encoding style.
[44]The XKMS binding shall use the SOAP
Request-Response Message Exchange Pattern defined in [SOAP1.2-2] and message
processing shall conform to that model. SOAP 1.2 messages carrying XKMS
content shall use the UTF-8 character encoding to insure
interoperability..
[45]SOAP 1.2 messages carrying XKMS content shall
conform to the following structure:
[46]XKMS Request Message
<?xml version='1.0' encoding="utf-8"?>
<env:Envelope xmlns:env="http://www.w3.org/2002/062003/05/soap-envelope/">
<env:Header>
<env:Body>
XKMS Request Message element
</env:Body>
</env:Header>
</env:Envelope>
[47]XKMS Response Message
<?xml version='1.0' encoding="utf-8"?>
<env:Envelope xmlns:env="http://www.w3.org/2002/062003/05/soap-envelope/">
<env:Header>
<env:Body>
XKMS Response Message element
</env:Body>
</env:Header>
</env:Envelope>;
[48]The XKMS SOAP message binding does not require
use of SOAP Headers. Headers may be used with SOAP messages carrying XKMS
content to provide additional services such as communications security or
routing. The use of such Headers is beyond the scope of this specification.
If used however, they must not alter the message encoding style or SOAP
processing model specified herein.
[49]Sample XKMS LocateRequest and LocateResponse
message communicated using SOAP 1.2 message transport are shown below:
[50]LocateRequest Message
<?xml version="1.0"?>
<env:Envelope xmlns:env="http://www.w3.org/2002/062003/05/soap-envelope/">
<env:Body>
<LocateRequest xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
Id="I94d1048aa24259465d7271cb4433dbb4"
Service="http://test.xmltrustcenter.org/XKMS"
xmlns="http://www.w3.org/2002/03/xkms#">
<RespondWith>KeyName</RespondWith>
<RespondWith>KeyValue</RespondWith>
<RespondWith>X509Cert</RespondWith>
<RespondWith>X509Chain</RespondWith>
<RespondWith>PGPWeb</RespondWith>
<RespondWith>PGP</RespondWith>
<RespondWith>Multiple</RespondWith>
<QueryKeyBinding>
<KeyUsage>Encryption</KeyUsage>
<UseKeyWith Application="urn:ietf:rfc:2440"
Identifier="bob@bobcorp.test"/>
<UseKeyWith Application="urn:ietf:rfc:2633"
Identifier="bob@bobcorp.test"/>
</QueryKeyBinding>
</LocateRequest>
</env:Body>
</env:Envelope>
<?xml version="1.0" encoding="utf-8"?>
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">
<env:Body>
<LocateRequest xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
Id="I8fc9f97052a34073312b22a69b3843b6"
Service="http://www.example.org/XKMS"
xmlns="http://www.w3.org/2002/03/xkms#">
<RespondWith>http://www.w3.org/2002/03/xkms#KeyName</RespondWith>
<RespondWith>http://www.w3.org/2002/03/xkms#KeyValue</RespondWith>
<RespondWith>http://www.w3.org/2002/03/xkms#X509Cert</RespondWith>
<RespondWith>http://www.w3.org/2002/03/xkms#X509Chain</RespondWith>
<RespondWith>http://www.w3.org/2002/03/xkms#PGPWeb</RespondWith>
<RespondWith>http://www.w3.org/2002/03/xkms#PGP</RespondWith>
<QueryKeyBinding>
<KeyUsage>http://www.w3.org/2002/03/xkms#Encryption</KeyUsage>
<UseKeyWith Application="urn:ietf:rfc:2440"
Identifier="bob@example.com" />
<UseKeyWith Application="urn:ietf:rfc:2633"
Identifier="bob@example.com" />
</QueryKeyBinding>
</LocateRequest>
</env:Body>
</env:Envelope>
[51]LocateResponse Message
<?xml version="1.0"?>
<env:Envelope xmlns:env="http://www.w3.org/2002/06/soap-envelope/">
<env:Body>
<LocateResult xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
Id="I075365c6e4d9feec5abf1d8a4504e4e8"
Service="http://test.xmltrustcenter.org/XKMS"
ResultMajor="Success"
RequestId="I94d1048aa24259465d7271cb4433dbb4"
xmlns="http://www.w3.org/2002/03/xkms#">
<KeyBinding Id="I9b2502783d8587288b55263b1332c83d">
<KeyInfo>
<ds:KeyValue>
<ds:RSAKeyValue>
<ds:Modulus>
4i0BEhQ8Jc4tjwZYbvtMyYfBrIGOMx34K4Cdo2pAzoGnV679FLmGHWnQy2cSj39hf5D1mIaPyD3j/
33TdfglTaaKqp7IPf6ei754fOuI/r1HpX7uqsw+j9LC4Z7GnG3yoY/eBJOZ8TRwMnx+Mkwm
opXPVLvhMWRyiUOcO3SEkTE=
</ds:Modulus>
<ds:Exponent>AQAB</ds:Exponent>
</ds:RSAKeyValue>
</ds:KeyValue>
<ds:X509Data>
<ds:X509Certificate>
MIIB+zCCAWigAwIBAgIQhzf6GHdFobRCYrjlFTCekjAJBgUrDgMCHQUAMBIxEDAOBgNVBAMTB1Rlc
3QgQ0EwHhcNMDIwNjEzMjEzMzQyWhcNMzkxMjMxMjM1OTU5WjAlMSMwIQYDVQQGExpVUyBP
PUJvYiBDb3JwIENOPUJvYiBCYWtlcjCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAtw2
qGqYbO0aKeZFb0Z3verx3Cp+KS94LiHG09D1DdgTd48FZaB5eXa4U3mLax2/Fsg/cxGZkXJ
ur0YylS8QvRuX+9STQgiFTO277sHFfRMvtFsuQ56ovrQWH/KoGQZssMUIqO2aN2cbMQJST3
a2HZuxqPQ1rwXxHrEoAXHZv3ysCAwEAAaNHMEUwQwYDVR0BBDwwOoAQRWvWDxzHMSR0xfgY
CUPpNqEUMBIxEDAOBgNVBAMTB1Rlc3QgQ0GCEHKxUcSI0WKITaXFa+Ylh5IwCQYFKw4DAh0
FAAOBgQCieDKjvNCo7MPs
gUwHydkid4KnulcuBbZet87lcIA7ReH1qEK4s0p49po2UM69eWG7hfv8LW2Ga8HiEexTwLD
FBvH2g7f09xI/vYgPw4qhJfWoZuY/HWHUzZIRSoggipndVfdvUkmsFSx1rR4FMu0mYBjq79
OkYsmwISQlaXejUg==
</ds:X509Certificate>
<ds:X509Certificate>
MIIB9zCCAWSgAwIBAgIQcrFRxIjRYohNpcVr5iWHkjAJBgUrDgMCHQUAMBIxEDAOBgNVBAMTB1Rlc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</ds:X509Certificate>
</ds:X509Data>
</KeyInfo>
<KeyUsage>Signature</KeyUsage>
<KeyUsage>Encryption</KeyUsage>
<KeyUsage>Exchange</KeyUsage>
<UseKeyWith Application="urn:ietf:rfc:2633"
Identifier="bob@bobcorp.test"/>
<Status StatusValue="Valid">
<Reason>Signature</Reason>
<Reason>ValidityInterval</Reason>
</Status>
</KeyBinding>
</LocateResult>
</env:Body>
</env:Envelope>
<?xml version="1.0" encoding="utf-8"?>
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">
<env:Body>
<LocateResult xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
Id="I8ce3809ab23500015cc27704b7eb0912"
Service="http://www.example.org/XKMS"
ResultMajor="http://www.w3.org/2002/03/xkms#Success"
RequestId="I8fc9f97052a34073312b22a69b3843b6"
xmlns="http://www.w3.org/2002/03/xkms#">
<UnverifiedKeyBinding Id="I809ca03cf85b3cb466859694dbd0627d">
<ds:KeyInfo>
<ds:KeyValue>
<ds:RSAKeyValue>
<ds:Modulus>
3FFtWUsvEajQt2SeSF+RvAxWdPPh5GSlQnp8SDvvqvCwE6PXcRWrIGmV7twNf2T
UXCxYuztUUClMIy14B0Q+k1ej2nekmYL7+Ic3DDGVFVaYPoxaRY0Y2lV8tOreyn
WegpFbITXc8V6Y02QfR5O7Pn1/10ElslaF/TF8MQGqYE8=
</ds:Modulus>
<ds:Exponent>AQAB</ds:Exponent>
</ds:RSAKeyValue>
</ds:KeyValue>
<ds:X509Data>
<ds:X509Certificate>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</ds:X509Certificate>
<ds:X509Certificate>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</ds:X509Certificate>
</ds:X509Data>
</ds:KeyInfo>
<KeyUsage>http://www.w3.org/2002/03/xkms#Signature</KeyUsage>
<KeyUsage>http://www.w3.org/2002/03/xkms#Encryption</KeyUsage>
<KeyUsage>http://www.w3.org/2002/03/xkms#Exchange</KeyUsage>
<UseKeyWith Application="urn:ietf:rfc:2633"
Identifier="bob@example.com"/>
</UnverifiedKeyBinding>
</LocateResult>
</env:Body>
</env:Envelope>
[52]The structure of conformant SOAP 1.2 messages
carrying other XKMS message types should be evident based on this example.
[53]XKMS implementers using SOAP 1.1 messaging
shall use request-response messaging and carry the XKMS messages as unencoded
content within the SOAP Body element. The SOAP 1.1 Section 5 encoding model
shall not be used. SOAP 1.1 messages carrying XKMS content shall use the
UTF-8 character encoding to insure interoperability.
[54]The structure of XKMS SOAP 1.1 messages shall
conform to:
[55]XKMS Request Message
<?xml version='1.0' encoding="utf-8"?>
<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope">
<env:Header>
<env:Body>
XKMS Request Message element
</env:Body>
</env:Header>
</env:Envelope>
[56]XKMS Response Message
<?xml version='1.0' encoding="utf-8"?>
<env:Envelope xmlns:env="http://schemas.xmlsoap.org/soap/envelope">
<env:Header>
<env:Body>
XKMS Response Message element
</env:Body>
</env:Header>
</env:Envelope>
[57]As with the SOAP 1.2 binding, the SOAP 1.1
binding does not require use of SOAP Headers. Headers may be used with SOAP
messages carrying XKMS content to provide additional services such as
communications security or routing providing they don't impact the encoding
style or SOAP processing model specified herein.
[58]SOAP 1.1 messages carrying XKMS content will
are identical to those using SOAP 1.2 except for the namespace of the
Envelope and Body elements. Hence, the examples shown in Section 3.1.1 are
conformant once the SOAP 1.2 namespace is replaced by the SOAP 1.1 namespace
(http://schemas.xmlsoap.org/soap/envelope).
[59]In using the XKMS SOAP binding, XKMS messages
are constructed as defined in Part 1 of this specification including all
required namespace declarations. The top-level message element is then
inserted as a child of the SOAP Body element. Promotion of XKMS namespace
declarations to the parent SOAP Body (or grandparent Envelope) element is not
required, but may be done at the discretion of the implementer. Such
namespace promotion is generally undesirable if the XKMS message contains a
digital signature as it may impact subsequent verification.
[60]Insertion of an XKMS message into the SOAP
message structure must not alter namespace prefixes, or use of default
namespaces, within the XKMS message. Any change in these encodings will
likely break an XML Signature internal to the XKMS messages due to the use of
QNames and namespace prefixes. The implementer must insure that prefix values
used with the SOAP namespaces http://www.w3.org/2002/06/soap-envelope/
http://www.w3.org/2003/05/soap-envelope/
(SOAP 1.2) and http://schemas.xmlsoap.org/soap/envelope
(SOAP 1.1) do not conflict with prefixes used in the XKMS message.
[61]Use of the XKMS SOAP binding does not affect
processing of the XML Signature-based elements <KeyBindingAuthentication> and <ProofOfPossession>. These are computed as described
in XKMS, sections 7.1.4 and 7.1.6
respectively, and the signature validation processing described in XKMS,
section 3.1.2 Element
<ds:Signature>." That is, the SOAP defined
nodes and namespaces do not contribute to the Signature computation.
[62]SOAP Faults shall be used by an XKMS service to
communicate errors that prevent the processing of a received XKMS request
message. XKMS clients should never send a SOAP Fault message to an XKMS
service.
[63]The following SOAP Fault messages are defined
for use with the XKMS SOAP 1.2 binding. Consistent with the SOAP 1.2
specification, these Fault messages shall contain the mandatory Code and
Reason element information items. Inclusion of other elements is at the
discretion of the implementer.
[64]In response to an XKMS request message, the
receiver shall respond with one of the following SOAP Faults if it is unable
to process the message. If it is able to process the message, then the
response should conform to a valid XKMS response message as described in Part
1.
- A fault with a Value of "env:VersionMismatch" for Code shall be
returned when the XKMS service finds an invalid element information item
instead of the expected Envelope element information item, or the
namespace, local name or both did not match the required Envelope element
information item. The Reason element shall be "Unsupported SOAP
version".
- A fault with a Value of "env:MustUnderstand" for Code shall be returned
if there is an immediate child element information item of the SOAP
Header element information item that was either not understood or not
obeyed by the faulting node when the Header contained a SOAP
mustUnderstand attribute information item with a value of "true". The
value for Reason shall be "Unable to process [header element name]" where
the expression in brackets is replaced by the header element information
item which caused the initial fault.
- A fault with a Value of "env:Receiver" for Code shall be generated when
the receiver cannot handle the message because of some temporary
condition, e.g. when it is out of memory. The Reason shall be "Service
temporarily unable".
- A fault with a Value of "env:Sender" for Code and a Value of
"xkms:MessageNotSupported" for Subcode shall be generated when the
receiver does not support the type of request message. The Reason shall
be "[XKMS message type] not supported" where the expression in brackets
is replace by the element information item name corresponding to the
received XKMS request message.
- A fault with a Value of "env:Sender" for Code and a Value of
"xkms:BadMessage" for Subcode shall be generated when the receiver cannot
parse the received XKMS message. The Reason shall be "[XKMS message type]
invalid" where the expression in brackets is replaced by the element
information item name corresponding to the received XKMS request
message.
[65]A sample SOAP 1.2 fault message that would be
returned when the received XKMS request message isn't supported by the
service is shown below:
<?xml version="1.0" ?>
<env:Envelope xmlns:env="http://www.w3.org/2002/06/soap-envelope/">
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope/">
<env:Body>
<env:Fault>
<env:Code>
<env:Value>env:Sender</env:Value>
<env:Subcode>
<env:Value>xkms:MessageNotSupported</env:Value>
</env:Subcode>
</env:Code>
<env:Reason>LocateRequest message not supported</env:Reason>
</env:Fault>
</env:Body>
</env:Envelope>
[66]The following SOAP Fault messages are defined
for use with the XKMS SOAP 1.1 binding. Consistent with the SOAP 1.1
specification, these Fault messages shall contain the faultcode and
faultstring elements. Inclusion of other elements is at the discretion of the
implementer.
[67]In response to an XKMS request message, the
receiver shall respond with one of the following SOAP Faults if it is unable
to process the message. If it is able to process the message, then the
response should conform to a valid XKMS response message as described in
[XKMS1].
- A fault with a faultcode of "env:VersionMismatch" shall be returned
when the XKMS service doesn't find the expected Envelope element or the
namespace, local name or both did not match the required Envelope
element. The faultstring element shall contain "Unsupported SOAP
version".
- A fault with a faultcode of "env:MustUnderstand" shall be returned if
there is an immediate child element of the SOAP Header element that was
either not understood or not obeyed by the faulting node when the header
contained a SOAP mustUnderstand attribute item with a value of
"
true1". The faultstring shall be "Unable to
process [header element name]" where the expression in brackets is
replaced by the first header element information item which caused the
fault.
- A fault with a faultcode of "env:Server" shall be returned when the
service cannot handle the message because of some temporary condition,
e.g. when it is out of memory. The faultstring shall be "Service
temporarily unable".
- A fault with a faultcode of "env:Client" shall be returned when the
receiver does not support the type of request message. The value for
faultstring shall be "[XKMS message type] not supported" where the
expression in brackets is replace by the element information item name
corresponding to the received XKMS request message.
- A fault with a faultcode of "env:Client" shall be returned when the
receiver cannot parse the received XKMS message. The faultstring shall be
"[XKMS message type] invalid" where the expression in brackets is replace
by the element information item name corresponding to the received XKMS
request message.
[68]A sample SOAP 1.1 fault message that would be
returned when the received XKMS request message isn't supported by the
service is shown below:
<?xml version="1.0" ?>
<env:Envelope xmlns:env="http://www.w3.org/2002/06/soap-envelope/http://schemas.xmlsoap.org/soap/envelope/">
<env:Body>
<env:Fault>
<env:faultcode>env:Client</env:faultcode>
<env:faultstring>LocateRequest message not supported</env:faultstring>
</env:Fault>
</env:Body>
</env:Envelope>
[69]When the XKMS binding to SOAP 1.2 is
implemented, the SOAP messages should be sent using HTTP POST consistent with
the recommendations of Section 6.4.2 in [SOAP1.2-2]. Processing shall be
consistent with Section 7, SOAP HTTP Binding in that specification.
[70]When the XKMS binding to SOAP 1.1 is
implemented, the SOAP messages should be sent using HTTP POST consistent with
the of Section 6.1 in [SOAP].
[71]This specification describes two principal
security bindings each of which specifies two or more specific implementation
profiles. Each implementation profile is assigned a unique URI to
facilitate negotiation of a specific security profile using some mechanism to
be described as a part of the wider Web Services framework.
| |
Payload Security |
Transaction Layer Security |
| Dependencies |
Authentication defined by XKMS
specification, client does not need to implement a comprehensive
framework. |
Authentication mechanism defined by TLS
which clients must implement |
| Use of XML Signature |
Uses XML Signature in Enveloped Mode
requiring slightly more complex processing. |
Not required |
| Support for Routing |
Specification describes bi-lateral
authentication only, multi-hop message routing and multi-party
transactions are not supported. |
None |
| Support for Confidentiality |
None, although applications may employ TLS
to establish a secure channel |
Supported |
| Non-Repudiation |
Supported |
Requires additional payload security |
| Unspecified Party Authentication |
Supported |
Requires additional payload security |
| Client Authentication |
Supported |
Supported through certificate client
authentication or through use of payload security. |
Identifier: http://www.w3.org/2002/03/xkms#payload-INo mechanism is used to authenticate the clientIdentifier: http://www.w3.org/2002/03/xkms#payload-IIThe client is authenticated using payload security
[71a]
- Client Authentication Modes:
- No mechanism is used to authenticate the client
- The client is authenticated using payload security
[71b]
In the following table, Request/Signature means that a XKMS Request
element includes a <dsig:Signature> element in enveloped
mode. This signature is calculated using a digital signature method.
Request/MAC has similar meaning, except that the signature is calculated
using a Message Authentication Code (MAC).
| Security Consideration |
Variant Client Authentication
Mode |
Support |
XKMS element Comment |
| Client
Authentication Mechanism |
I No
authentication mechanism is used.to authenticate the
client |
None |
|
| |
II The
client is authenticated Authentication using payload
security |
Payload |
Request/Signature |
| Service
Authentication Mechanism |
-- Not
Applicable |
Payload |
Response/Signature |
Request/Response
Correspondence |
INo
mechanism is used. to authenticate the client |
Payload |
Request/MessageDigest |
| Request/Response
Correspondence |
II The
client is authenticated Authentication using payload
security |
Payload |
Message/RequestId |
| Replay
Attack Protection |
-- Any |
Payload |
Message/Nonce in Two-phase protocol |
| Denial Of
Service Protection |
--
Any |
Payload |
Request/RespondWith=Represent |
| Non
Repudiation |
--
Any |
Payload |
Message/Signature with digital signature |
[72] The following payload security features are
employed:
| XKMS element.attribute name |
Required |
| MessageAbstractType.Service |
Required |
| MessageAbstractType.Signature |
Required in profile II where client is
authenticated using payload security for both Request and Response
Messages |
Response/Signature |
Required |
| ResultType.RequestId |
Required |
| PendingRequestType.ResponseId |
Required |
| MessageAbstractType.Nonce |
Optional, may be used to protect against Denial of
Service |
| MessageAbstractType.RespondWith=Represent |
Optional, may be used to protect against Denial of
Service |
Request/MessageDigest.Signature
with MAC |
Required in profile I where no
mechanism is used to authenticate the client, Optional in
profile II where client is authenticated using
payload security |
[73]When TLS is to be used in XKMS, XKMS responders
MUST support server authenticated TLS. Note that this means that an XKMS
client need only support anonymous TLS, since to require otherwise would mean
that all XKMS clients would have to be able to store root certificates for
TLS usage.
All XKMS clients and responders which support TLS MUST support the
TLS_RSA_WITH_3DES-EDE_CBC_SHA ciphersuite.
Other ciphersuites MAY be supported, but weak ciphersuites intended to meet
export restrictions ("export grade") are NOT RECOMMENDED to be supported."
[74]The SSL/TLS binding has three variants
specified by the following identifiers client authentication
modes:
Identifier: http://www.w3.org/2002/03/xkms#tls-INo mechanism is used to authenticate the clientIdentifier: http://www.w3.org/2002/03/xkms#tls-IITLS certificate based client authentication is used to
authenticate the clientIdentifier: http://www.w3.org/2002/03/xkms#tls-IIIPayload security is used for client authentication
- SSL/TLS Client Authentication Mode
- No mechanism is used to authenticate the client
- TLS certificate based client authentication is used to authenticate
the client
- Payload security is used for client authentication
[74a]
| Security Consideration |
Variant Client
Authentication Mode |
Support |
XKMS element Comment |
| Client Authentication Mechanism |
I No authentication mechanism is used
to authenticate the client |
None |
|
| |
II TLS certificate based client
authentication is used. to authenticate the
client |
TLS |
Certificate based client authentication |
| |
II Authentication using Payload
security. is used for client authentication |
Payload |
Request/Signature |
| Service Authentication Mechanism |
-- |
TLS |
|
| Request/Response Correspondence |
-- |
TLS |
|
| Replay Attack Protection |
-- |
TLS |
|
| Denial Of Service Protection |
-- |
None |
The TLS service is subject to a denial of service
attack [Check this] |
| Non Repudiation |
-- |
Payload |
Message/Signature with digital signature [if
required] |
[75] The following payload security features are
employed:
| XKMS element.attribute name |
Required |
| MessageAbstractType.Service |
Required, but not dependent |
| MessageAbstractType.Signature |
Optional, may be used to support non-repudiation for
both Request and Response messages |
| ResultType.RequestId |
Required, but not dependent |
| PendingRequestType.ResponseId |
Required, but not dependent |
| MessageAbstractType.Nonce |
Unnecessary |
| MessageAbstractType.RespondWith=Represent |
Unnecessary |
Request/MessageHash |
Unnecessary |
[76] [RFC2119]S. Bradner, Key words for use in RFCs
to Indicate Requirement Levels, IETF RFC 2119, March 1997, http://www.ietf.org/rfc/rfc2119.txt.
[77] [RFC2246] T.
Dierks, C. Allen., The TLS Protocol Version, 1.0. IETF RFC 2246
January 1999. http://www.ietf.org/rfc/rfc2246.txt
[78] [RFC2693] C. Ellison et. al., Simple Public Key
Infrastructure Certificate Theory, IETF RFC 2693, Sept. 1999, http://www.ietf.org/rfc/rfc2693.txt
[79] [RFC3280] R. Housley et. al., Public Key Infrastructure
(X.509) (PKIX) Certificate and Certificate Revocation List (CRL) Profile,
IETF RFC 3280, April 2002 ,http://www.ietf.org/rfc/rfc3280.txt
[80] [SOAP] D.
Box, D Ehnebuske, G. Kakivaya, A. Layman, N. Mendelsohn, H. Frystyk Nielsen,
S Thatte, D. Winer. Simple Object Access Protocol (SOAP) 1.1, W3C Note
08 May 2000, http://www.w3.org/TR/2000/NOTE-SOAP-20000508/
[81] [SOAP1.2-1] Martin Gudgin, et al. SOAP Version 1.2
Part 1: Messaging Framework, W3C Recommendation 24 June 2003, http://www.w3.org/TR/2003/REC-soap12-part1-20030624/
[82] [SOAP1.2-2] Martin Gudgin, et al. SOAP Version 1.2
Part 2: Adjuncts, W3C Recommendation 24 June 2003, http://www.w3.org/TR/2003/REC-soap12-part2-20030624/
[83] [WSDL] E.
Christensen, F. Curbera, G. Meredith, S. Weerawarana, Web Services
Description Language (WSDL) 1.0 September 25, 2000, http://msdn.microsoft.com/xml/general/wsdl.asp
[84][WS-TrustAxiom]P. Hallam-Baker et.
al.,WS-Trust Axiom, To be published
[85] [XML-SIG] D. Eastlake, J. R., D. Solo, M. Bartel,
J. Boyer , B. Fox , E. Simon. XML-Signature Syntax and Processing,
World Wide Web Consortium. http://www.w3.org/TR/xmldsig-core/
[86] [XML-SIG-XSD] XML Signature Schema available from
http://www.w3.org/TR/xmldsig-core/xmldsig-core-schema.xsd
[87] [XML-Enc]Donald Eastlake, Joseph Reagle, Takeshi
Imamura, Blair Dillaway, Ed Simon, XML Encryption Syntax and
Processing, World Wide Web Consortium, http://www.w3.org/TR/xmlenc-core/
[88] [XML-NS] T. Bray, D. Hollander, A. Layman.
Namespaces in XML. W3C Recommendation. January 1999. http://www.w3.org/TR/1999/REC-xml-names-19990114
[89] [XML-Schema1] H. S. Thompson, D. Beech, M. Maloney,
N. Mendelsohn. XML Schema Part 1: Structures, W3C Recommendation 2 May
2001, http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/,
latest draft at http://www.w3.org/TR/xmlschema-1/
[90] [XML-Schema2] P. V. Biron, A. Malhotra, XML
Schema Part 2: Datatypes; W3C Recommendation 2 May 2001, http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/,
latest draft at http://www.w3.org/TR/xmlschema-2/
This appendix documents changes (other than very minor editorial changes)
made since the xx.xx of the XKMS 2.0 Specification.
Shivaram: August 20th Draft
- Issue 320-6: Fixed Para 50 - deleted line
<RespondWith>Multiple</RespondWith>
- Issue 320-7: Fixed Para 67 - replaced "true" with "1"
- Issue 320-8: Fixed Para 68 - Fixed with correct URI for SOAP schema
location
- Issue 320-9: Fixed Para 46, 47, 50, 60 - Fixed with correct URI for
SOAP 1.2 Schema
- Added Appendix B Changes section and also to the table of
contents
Jose: Oct 12th Draft
- Fixed html typos
- Issue 320-9: Added a missing convertion, added a envelope/ rather
than envelope
Shivaram: Oct 25th Draft
- Fixed Para[50] LocateRequest- SOAP12 - Updated to use URIs instead
of QNames
- Fixed Para[51] LocateResult- SOAP12 - Updated
Shivaram: February 24th Draft
- Issue 328-jk: Updated Section 4.1 - 2 tables and also in para [72]
related to Payload URIs (which are non-existent) and text. Removed
URIs and replaced it with text. Deleted sentence in para[71] related
to profile URIs. Changed "Variants" to "Client Authentication Modes"
in para [74]
- Removed Para [84] - reference to ws-trustaxiom which is
non-existent. Updated para [21] correspondingly.
Shivaram: April 07th Draft
- Issue 328-jk: Updated table para [71b]
- Added para numbers [71a], [71b], [74a] for exisiting text for
better clarity.
- Updated Table para [74a] with better text for client authentication
mode column.
- Table Para [74a] - Check description of Denial Of Service
row - TODO.
- Proposing [72a] as a replacement for para [72] for better
clarification of the text - need feedback
- Proposing [75a] as a replacement for para [75] for better
clarification of the text - need feedback
Shivaram: April 18th Draft
- Issue 328-jk: Updated para [71b] - added clarification paragraph
before the table.
- Changed -- in table of [71b] with "Not Applicable"
- Deleted Row in table [71b] which corresponds to Request/Response
Correspondence with XKMS element Request/MessageDigest as it was an
error.
- Table in para [71b] - for Replay Attack, DOS, and Non Repudiation
Protection, added "Any" as the client authentication mode.
- Table in para [71b] - For Replay Attack, XKMS element column, added
qualifier - "in two-phase protocol"
- Table in para [72], changed Request/MessageDigest to
Request.Signature with MAC - which is more accurate
- Changed table column name "XKMS element" to "Comment" in para [71b]
and [74a]
Specification changes between CR and PR
- Issues Fixed:
- Issue
320-6: Fixed Para 50 - deleted line
<RespondWith>Multiple</RespondWith>
- Issue
320-7: Fixed Para 67 - replaced "true" with "1"
- Issue
320-8: Fixed Para 68 - Fixed with correct URI for SOAP schema
location
- Issue
320-9: Fixed Para 46, 47, 50, 60 - Fixed with correct URI for
SOAP 1.2 Schema; Added a missing converstion, added a envelope/
rather than envelope.
- Issue
328-jk: Updated Section 4.1 - 2 tables and also in para [72]
related to Payload URIs (which are non-existent) and text. Removed
URIs and replaced it with text. Deleted sentence in para[71] related
to profile URIs. Changed "Variants" to "Client Authentication Modes"
in para [74]
- Added Appendix B Changes section and also to the table of
contents
- Editorial Fixes:
- Fixed html typos
- Fixed Para[50] LocateRequest- SOAP12 - Updated to use URIs instead
of QNames
- Fixed Para[51] LocateResult- SOAP12 - Updated
- Removed Para [84] - reference to ws-trustaxiom which is
non-existent. Updated para [21] correspondingly.