Network Working Group A. Petersson
Internet-Draft M. Nilsson
Intended status: Standards Track Opera Software
Expires: April 12, 2013 October 9, 2012
Forwarded HTTP Extension
draft-ietf-appsawg-http-forwarded-10
Abstract
This document defines an HTTP extension header field that allows
proxy components to disclose information lost in the proxying
process, for example, the originating IP address of a request or IP
address of the proxy on the user-agent-facing interface. In a path
of proxying components, this makes it possible to arrange it so that
each subsequent component will have access to, for example, all IP
addresses used in the chain of proxied HTTP requests.
This document also specifies guidelines for a proxy administrator to
anonymize the origin of a request.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months
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This Internet-Draft will expire on April 12, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 5
3. Syntax Notations . . . . . . . . . . . . . . . . . . . . . . . 5
4. Forwarded HTTP Header Field . . . . . . . . . . . . . . . . . 5
5. Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5.1. Forwarded By . . . . . . . . . . . . . . . . . . . . . . . 7
5.2. Forwarded For . . . . . . . . . . . . . . . . . . . . . . 7
5.3. Forwarded Host . . . . . . . . . . . . . . . . . . . . . . 8
5.4. Forwarded Proto . . . . . . . . . . . . . . . . . . . . . 8
5.5. Extensions . . . . . . . . . . . . . . . . . . . . . . . . 8
6. Node Identifiers . . . . . . . . . . . . . . . . . . . . . . . 8
6.1. IPv4 and IPv6 Identifiers . . . . . . . . . . . . . . . . 10
6.2. The "unknown" Identifier . . . . . . . . . . . . . . . . . 10
6.3. Obfuscated Identifier . . . . . . . . . . . . . . . . . . 10
7. Implementation Considerations . . . . . . . . . . . . . . . . 10
7.1. HTTP Lists . . . . . . . . . . . . . . . . . . . . . . . . 10
7.2. Header Field Preservation . . . . . . . . . . . . . . . . 11
7.3. Relation to Via . . . . . . . . . . . . . . . . . . . . . 11
7.4. Transition . . . . . . . . . . . . . . . . . . . . . . . . 11
7.5. Example Usage . . . . . . . . . . . . . . . . . . . . . . 12
8. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8.1. Header Validity and Integrity . . . . . . . . . . . . . . 13
8.2. Information Leak . . . . . . . . . . . . . . . . . . . . . 13
8.3. Privacy Considerations . . . . . . . . . . . . . . . . . . 13
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
10.1. Normative References . . . . . . . . . . . . . . . . . . . 15
10.2. Informative References . . . . . . . . . . . . . . . . . . 16
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