Gossiping in CT
draft-ietf-trans-gossip-04
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Active Internet-Draft (trans WG)
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Last updated |
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2017-04-21
(latest revision 2017-01-10)
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Replaces |
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draft-linus-trans-gossip-ct
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Stream |
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IETF
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Intended RFC status |
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Experimental
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plain text
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html
bibtex
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Submitted to IESG for Publication
(wg milestone:
Oct 2016 - Gossip draft to work...
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Document shepherd |
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Melinda Shore
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Shepherd write-up |
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Show
(last changed 2017-03-16)
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| IESG |
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AD Evaluation
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Consensus Boilerplate |
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Unknown
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Responsible AD |
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Eric Rescorla
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Send notices to |
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"Melinda Shore" <melinda.shore@gmail.com>
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TRANS L. Nordberg
Internet-Draft NORDUnet
Intended status: Experimental D. Gillmor
Expires: July 14, 2017 ACLU
T. Ritter
January 10, 2017
Gossiping in CT
draft-ietf-trans-gossip-04
Abstract
The logs in Certificate Transparency are untrusted in the sense that
the users of the system don't have to trust that they behave
correctly since the behavior of a log can be verified to be correct.
This document tries to solve the problem with logs presenting a
"split view" of their operations. It describes three gossiping
mechanisms for Certificate Transparency: SCT Feedback, STH
Pollination and Trusted Auditor Relationship.
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
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 14, 2017.
Copyright Notice
Copyright (c) 2017 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
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
Nordberg, et al. Expires July 14, 2017 [Page 1]
Internet-Draft Gossiping in CT January 2017
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Defining the problem . . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Pre-Loaded vs Locally Added Anchors . . . . . . . . . . . 5
5. Who gossips with whom . . . . . . . . . . . . . . . . . . . . 5
6. What to gossip about and how . . . . . . . . . . . . . . . . 6
7. Data flow . . . . . . . . . . . . . . . . . . . . . . . . . . 6
8. Gossip Mechanisms . . . . . . . . . . . . . . . . . . . . . . 7
8.1. SCT Feedback . . . . . . . . . . . . . . . . . . . . . . 7
8.1.1. SCT Feedback data format . . . . . . . . . . . . . . 8
8.1.2. HTTPS client to server . . . . . . . . . . . . . . . 8
8.1.3. HTTPS server operation . . . . . . . . . . . . . . . 11
8.1.4. HTTPS server to auditors . . . . . . . . . . . . . . 13
8.2. STH pollination . . . . . . . . . . . . . . . . . . . . . 14
8.2.1. HTTPS Clients and Proof Fetching . . . . . . . . . . 15
8.2.2. STH Pollination without Proof Fetching . . . . . . . 17
8.2.3. Auditor Action . . . . . . . . . . . . . . . . . . . 17
8.2.4. STH Pollination data format . . . . . . . . . . . . . 17
8.3. Trusted Auditor Stream . . . . . . . . . . . . . . . . . 17
8.3.1. Trusted Auditor data format . . . . . . . . . . . . . 18
9. 3-Method Ecosystem . . . . . . . . . . . . . . . . . . . . . 19
9.1. SCT Feedback . . . . . . . . . . . . . . . . . . . . . . 19
9.2. STH Pollination . . . . . . . . . . . . . . . . . . . . . 20
9.3. Trusted Auditor Relationship . . . . . . . . . . . . . . 21
9.4. Interaction . . . . . . . . . . . . . . . . . . . . . . . 22
10. Security considerations . . . . . . . . . . . . . . . . . . . 22
10.1. Attacks by actively malicious logs . . . . . . . . . . . 22
10.2. Dual-CA Compromise . . . . . . . . . . . . . . . . . . . 23
10.3. Censorship/Blocking considerations . . . . . . . . . . . 24
10.4. Flushing Attacks . . . . . . . . . . . . . . . . . . . . 25
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