Internet DRAFT - draft-tbruijnzeels-sidr-delta-protocol
draft-tbruijnzeels-sidr-delta-protocol
Network Working Group T. Bruijnzeels
Internet-Draft O. Muravskiy
Intended status: Standards Track RIPE NCC
Expires: June 23, 2015 B. Weber
Cobenian
R. Austein
Dragon Research Labs
D. Mandelberg
BBN Technologies
December 22, 2014
RPKI Repository Delta Protocol
draft-tbruijnzeels-sidr-delta-protocol-03
Abstract
In the Resource Public Key Infrastructure (RPKI), certificate
authorities publish certificates, including end entity certificates,
and CRLs to repositories on publication servers. Relying Parties
(RP) retrieve the published information from the repository and MAY
store it in a cache. This document specifies a delta protocol which
provides relying parties with a mechanism to query a repository for
changes, thus enabling the RP to keep its state in sync with the
repository.
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 June 23, 2015.
Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 1]
Internet-Draft RPKI Repository Delta Protocol December 2014
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 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. Requirements notation . . . . . . . . . . . . . . . . . . . . 2
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
3. RPKI Repository Delta Protocol Implementation . . . . . . . . 3
3.1. Informal Overview . . . . . . . . . . . . . . . . . . . . 3
3.2. Update Notification File . . . . . . . . . . . . . . . . . 5
3.2.1. Purpose . . . . . . . . . . . . . . . . . . . . . . . 5
3.2.2. Cache Concerns . . . . . . . . . . . . . . . . . . . . 5
3.2.3. File Format and Validation . . . . . . . . . . . . . . 5
3.2.4. Publication Server Initialisation . . . . . . . . . . 6
3.2.5. Publishing Updates . . . . . . . . . . . . . . . . . . 6
3.3. Snapshot File . . . . . . . . . . . . . . . . . . . . . . 7
3.3.1. Purpose . . . . . . . . . . . . . . . . . . . . . . . 7
3.3.2. Cache Concerns . . . . . . . . . . . . . . . . . . . . 7
3.3.3. File Format and Validation . . . . . . . . . . . . . . 8
3.4. Delta File . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.1. Purpose . . . . . . . . . . . . . . . . . . . . . . . 10
3.4.2. Cache Concerns . . . . . . . . . . . . . . . . . . . . 11
3.4.3. File Format and Validation . . . . . . . . . . . . . . 11
3.5. SIA for CA certificates . . . . . . . . . . . . . . . . . 13
4. Relying Party Use . . . . . . . . . . . . . . . . . . . . . . 14
4.1. Full Synchronisation . . . . . . . . . . . . . . . . . . . 14
4.2. Processing Deltas . . . . . . . . . . . . . . . . . . . . 14
5. XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 17
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
1. Requirements notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Introduction
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 2]
Internet-Draft RPKI Repository Delta Protocol December 2014
In the Resource Public Key Infrastructure (RPKI), certification
authorities (CAs) publish certificates [RFC6487], RPKI signed
objects [RFC6488] , manifests [RFC6486] and CRLs to repositories.
CAs may have an embedded mechanism to publish to these repositories,
or they may use a separate publication server and communication
protocol. RPKI repositories are currently accessible using rsync,
allowing Relying Parties (RPs) to synchronise a local copy of the
RPKI repository used for validation with the central repositories
using the rsync protocol [RFC6481].
This document specifies an alternative repository access protocol
based on notification, snapshot and delta files that an RP can
retrieve over http(s). This allows RPs to perform a full
(re-)synchronisation of their local copy of the repository using
snapshot files. However, typically RPs will use delta files to keep
their local repository updated after initial synchronisation.
This protocol is designed to be consistent with the publication
protocol [I-D.ietf-sidr-publication] and treats publication events of
one or more repository objects as immutable events that can be
communicated to relying parties. This approach helps to minimize the
amount of data that traverses the network and thus helps minimize the
amount of time until repository convergence occurs. This protocol
also provides a standards based way to obtain consistent, point in
time views of a single repository eliminating a number of consistency
related issues. Finally, this approach allows for caching
infrastructure to be used to serve this immutable data, and thus
helps to reduce the load on a publication server when a large a
number of relying parties are querying it.
3. RPKI Repository Delta Protocol Implementation
3.1. Informal Overview
Certification Authorities (CA) in the RPKI use a publication server
to publish their RPKI products, such as manifests, CRLs, signed
certificates and RPKI signed objects. This publication server may be
remote, or embedded in the CA engine itself. Certificates in the
RPKI that use a publication server that supports this delta protocol
include a special Subject Information Access (SIA) pointer referring
to a notification file.
The notification file includes a globally unique session_id in the
form of a version 4 UUID, and serial number that can be used by the
Relying Party (RP) to determine if it and the repository are
synchronised. Furthermore it includes a link to the most recent
complete snapshot of current objects that are published by the
publication servers, and a list of links to delta files, for each
revision starting at a point determined by the publication server, up
to the current revision of the repository.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 3]
Internet-Draft RPKI Repository Delta Protocol December 2014
This notification file is intended to be small so that is can easily
be fetched over HTTP(S). The publication server may use HTTP caching
infrastructure to reduce its load. The publication server should
should avoid using a long caching interval, since the length of this
interval determines when RPs will receive updated notification files,
and thereby new products produced by Certification Authorities using
this publication server. It is recommended that of no longer than
five minutes is used for caching this file. If the caching
infrastructure supports it another useful approach would be to expire
the cache for the notification file URI as soon as a new notification
file is known to be published.
An RP that first learns about a notification file location can
download it, and then proceed to download the latest snapshot file,
and thus create a local copy of the repository that is in sync with
the publication server. The RP should remember the location of this
notification file, the session_id and current serial number.
RPs are encouraged to re-fetch this notification file at regular
intervals, but should not try to fetch the same file more frequently
than once per minute. After re-fetching the notification file, the
RP may find that there are one or more delta files available that
allow it to synchronise with the current state.
If no contiguous chain of updates is available, or if the session_id
has changed, the latest snapshot should be used instead. In this
case the RP should then add the objects found in the latest snapshot
to its local repository.
As soon as the RP fetches new content in this way it should start a
validation process using its local repository. An example of a
reason why an RP may not do this immediately is because it has
learned of more than one notification location and it prefers to
complete all its updates before validating.
The publication server may use http caching infrastructure to reduce
its load. It should be noted that snapshots and deltas for any given
session_id and serial number contain an immutable record of the state
of the publication server at a certain point in time. For this
reason these files can be cached indefinitely. To support this the
publication server must use a globally unique URL for the location of
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 4]
Internet-Draft RPKI Repository Delta Protocol December 2014
each of these snapshot and delta files. It is recommended that old
versions of snapshot and delta files remain available for download
for some time after they have last appeared on a notification file to
provide some resiliency in case relying parties are slow to process.
3.2. Update Notification File
3.2.1. Purpose
The update notification file is used by RPs to discover whether any
changes exist between the state of the publication server's
repository and the RP's cache. It describes the location of the
files containing the snapshot and incremental deltas which can be
used by the RP to synchronize with the repository.
3.2.2. Cache Concerns
A repository server MAY use caching infrastructure to cache the
notification file and reduce the load of http(s) requests to a
central repository server. However, since this file is used by RPs
to determine whether any updates are available it is strongly
RECOMMENDED to use a short interval for caching, to avoid unnecessary
delays. A maximum of delay of 5 minutes after a new notification
file has been published seems like a reasonable compromise. This
delay should not cause major problems for RPs and routing since a
similar human time scale is expected to be involved in updating the
contents of the RPKI on the one hand, i.e. creating and publishing
new ROAs or router certificates, and updating actual BGP
announcements in routers on the other. That said, real world
measurements are needed on this subject, so this recommended maximum
time may be subject to change in future.
There are various ways to ensure that the notification file is only
cached for a certain time in caching infrastructure and different
solutions, such as commercial Content Delivery Networks (CDNs), may
provide different ways of achieving this. For example some CDNs have
custom support to cache a file such as this notification file
indefinetely, but allow a central server to notify the CDN through
some protocol that an update is available and trigger the CDN to then
refresh this file. In general a publication server may find certain
HTTP headers to be useful, such as: Cache-Control: max-age=300
Finally it shoulf be noted that snapshot and delta files are intended
to be cache-able for a much longer longer time. In support of this
the URIs for each snapshot and delta file for a given session_id and
serial number MUST be unique and the contents of those files MUST NOT
change.
3.2.3. File Format and Validation
Example notification file:
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 5]
Internet-Draft RPKI Repository Delta Protocol December 2014
<notification xmlns="HTTP://www.ripe.net/rpki/rrdp" version="1" session_id="9df4b597-af9e-4dca-bdda-719cce2c4e28" serial="2">
<snapshot uri="HTTP://rpki.ripe.net/rpki-ca/rrdp/EEEA7F7AD96D85BBD1F7274FA7DA0025984A2AF3D5A0538F77BEC732ECB1B068.xml" hash="EEEA7F7AD96D85BBD1F7274FA7DA0025984A2AF3D5A0538F77BEC732ECB1B068"/>
<delta serial="2" uri="HTTP://rpki.ripe.net/rpki-ca/rrdp/198BD94315E9372D7F15688A5A61C7BA40D318210CDC799B6D3F9F24831CF21B.xml" hash="198BD94315E9372D7F15688A5A61C7BA40D318210CDC799B6D3F9F24831CF21B"/>
<delta serial="1" uri="HTTP://rpki.ripe.net/rpki-ca/rrdp/8DE946FDA8C6A6E431DFE3622E2A3E36B8F477B81FAFCC5E7552CC3350C609CC.xml" hash="8DE946FDA8C6A6E431DFE3622E2A3E36B8F477B81FAFCC5E7552CC3350C609CC"/>
</notification>
The following validation rules must be observed when creating or
parsing notification files:
o A RP MUST NOT process any update notification file that is not
well formed, or which does not conform to the RELAX NG schema
outlined in Section 5 of this document.
o The XML namespace MUST be HTTP://www.ripe.net/rpki/rrdp
o The encoding MUST be us-ascii
o The version attribute in the notification root element MUST be 1
o The session_id attribute MUST be a random version 4 UUID unique to
this session
o The serial attribute must be an unbounded, unsigned positive
integer indicating the current version of the repository.
o The notification file MUST contain exactly one 'snapshot' element
for the current repository version.
o If delta elements are included they MUST form a contiguous
sequence starting at a revision determined by the publication
server, up to the current version of the repository.
o The hash attribute in snapshot and delta elements must be the
hexadecimal encoding of the SHA-256 hash of the referenced file.
The RP SHOULD verify this hash when the file is retrieved and
reject it if it does not match.
3.2.4. Publication Server Initialisation
When the publication server (re-) initialises it MUST generate a new
random version 4 UUID to be used as the session_id. Furthermore it
MUST then generate a snapshot file for serial number ONE for this new
session that includes all currently known published objects that the
publication server is responsible for. This snapshot file MUST be
made available at a URL that is unique to this session and version,
so that it can be cached indefinitely. The format and caching
concerns for snapshot files are explained in more detail below in
Section 3.3. After the snapshot file has been published the
publication server MUST publish a new notification file that contains
the new session_id, has serial number ONE, has one reference to the
snaphot file that was just published, and that contains no delta
references.
3.2.5. Publishing Updates
Whenever the publication server receives updates from a CA it SHOULD
generate an update as follows.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 6]
Internet-Draft RPKI Repository Delta Protocol December 2014
The new repository serial MUST be one greater than the current
repository serial. A new delta file MUST be generated for this new
serial, that contains all the updates, i.e. new, replaced and
withdrawn objects, as a single change set. This delta file MUST be
made available at a URL that is unique to this session and version,
so that it can be cached indefinitely. The format and caching
concerns for delta files are explained in more detail below in
Section 3.4.
The publication server MUST also generate a new snaphost file for
this new serial, that contains all current objects for this new
serial. In other words it should include all publish elements found
in this update, and it should exclude all previous publish elements
for objects that have been withdrawn or updated. As above this new
file MUST be made available at a URL that is unique to this
session_id and new version before proceeding.
Finally an updated notification file MUST be created by the
publication server. This new notification file MUST include a
reference to the new snaphot file. The file SHOULD also include
available delta files for this and previous updates. However, the
server MUST not include more delta files than, when combined, exceed
the size of the current snapshot.
The publication server MAY also choose to include fewer delta files
if it is found that the efficiency gain in keeping notification files
small outweighs the overhead of forcing a small number of relying
parties to process full snapshot files. At the time of this writing
it is not completely clear what would constitute reasonable
parameters to determine this balance. Real world measurements are
needed to help this discussion. Possible approaches are:
o The publication server may learn the retrieval distribution of old
delta files by RPs over time, and decide to exclude deltas from
the point where less than e.g. 0.1% of RPs would retrieve them.
o The server may decide to support deltas only for a limited time,
e.g. 6 hours. So that RPs can recover easily from restart or
reasonably short outage scenarios, and are only forced to do a
full re-sync in case of prolonged outages.
If the publication server is not capable of performing the above for
some reason, then it MUST perform a full re-initialisation, as
explained above in Section 3.2.4.
3.3. Snapshot File
3.3.1. Purpose
A snapshot is intended to reflect the complete and current contents
of the repository. There it MUST contain all objects from the
repository current as of the time of the publication.
3.3.2. Cache Concerns
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 7]
Internet-Draft RPKI Repository Delta Protocol December 2014
A repository server MAY use caching infrastructure to cache snapshot
files and reduce the load of http(s) requests to a central repository
server. To support this it is important that snaphot files for a
specific session_id and serial have a unique URL. The files
themselves reflect the content of the repository at a specific point
in time, and for that reason they never change. Aside from space
concerns this means that these files MAY therefore be cached
indefinitely.
To support RPs that are slow to process old, possibly cached,
notification files, the publication server SHOULD ensure that old
snapshot files remain available for some time after have last
appeared on a notification file. It is RECOMMENDED that these files
are kept for at least two times as long as the notification file
cache period, i.e. 10 minutes. However, space permitting, the
publication server is welcome to keep these files available for
longer.
3.3.3. File Format and Validation
Example snapshot file:
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 8]
Internet-Draft RPKI Repository Delta Protocol December 2014
<snapshot xmlns="HTTP://www.ripe.net/rpki/rrdp" version="1" session_id="9df4b597-af9e-4dca-bdda-719cce2c4e28" serial="5932">
<publish uri="rsync://bandito.ripe.net/repo/671570f06499fbd2d6ab76c4f22566fe49d5de60.cer">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</publish>
<publish uri="rsync://bandito.ripe.net/repo/77821ba152e5fbd6c46c3e95ac2b27a910a514d5.mft">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, Muravskiy, WExpiresuJunen23,M2015 [Page 9]
Internet-Draft RPKI Repository Delta Protocol December 2014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==
</publish>
<publish uri="rsync://bandito.ripe.net/repo/77821ba152e5fbd6c46c3e95ac2b27a910a514d5.crl">
MIIBnzCBiAIBATANBgkqhkiG9w0BAQsFADANMQswCQYDVQQDEwJUQRcNMTQxMjAzMTgwODMyWhcN
MTQxMjA0MTgwODMyWjAVMBMCAguXFw0xNDEyMDMxODA4MzJaoDAwLjAfBgNVHSMEGDAWgBR3ghuh
UuX71sRsPpWsKyepEKUU1TALBgNVHRQEBAICC5YwDQYJKoZIhvcNAQELBQADggEBAFQHr/2ids7e
hmfnX+PmyePSN2EM1fBMLwMud6dqyBF42iNa8N0H/jxMAkgm7SS98TUupZg1aIwqxLwGakFS6VeD
+zCnCGEeMUlXTpZaICDxMxJuJLBOVbqP2amPxWJ22g0+gTXM9KPAoWlNyAiMaNUP+nawjyfMzQ4c
WJjIi1kRHnIhiu9cZwEh9Ns/sC3adPJ8NV6LPpMkQDQvIynxV/fbTf/EwwwRfLy1szGLZSdml4G0
gHohkWaosr4R2A7sZOc/PZGtstqpBRTD8RwVJx0pseC6Zp/01WH/FjzNpXahFPgR1QXy3qBGEHRh
xA08g0+QiGSz+QX5PPQ2dBkTRIY=
</publish>
</snapshot>
The following validation rules must be observed when creating or
parsing snapshot files:
o A RP MUST NOT process any snapshot file that is not well formed,
or which does not conform to the RELAX NG schema outlined in
Section 5 of this document.
o The XML namespace MUST be HTTP://www.ripe.net/rpki/rrdp.
o The encoding MUST be us-ascii.
o The version attribute in the notification root element MUST be 1
o The session_id attribute MUST match the expected session_id in the
reference in the notification file.
o The serial attribute MUST match the expected serial in the
reference in the notification file.
o The hexadecimal encoding of the SHA-256 hash of this snapshot file
MUST match the hash attribute in the reference in the notification
file.
3.4. Delta File
3.4.1. Purpose
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 10]
Internet-Draft RPKI Repository Delta Protocol December 2014
An incremental delta file contains all changes for exactly one serial
increment of the publication server. In other words a single delta
will typically include all the new objects, updated objects and
withdrawn objects that a Certification Authority sent to the
publication server. In its simplest form the update could concern
only a single object, but it is recommended that CAs send all changes
for one of their key pairs: i.e. updated objects as well as a new
manifest and CRL as one atomic update message.
3.4.2. Cache Concerns
A repository server MAY use caching infrastructure to cache delta
files and reduce the load of http(s) requests to a central repository
server. To support this it is important that delta files for a
specific session_id and serial have a unique URL. The files
themselves reflect the content of the repository at a specific point
in time, and for that reason they never change. Aside from space
concerns this means that these files MAY therefore be cached
indefinitely.
To support RPs that are slow to process old, possibly cached,
notification files, the publication server SHOULD ensure that old
delta files remain available for some time after have last appeared
on a notification file. It is RECOMMENDED that these files are kept
for at least two times as long as the notification file cache period,
i.e. 10 minutes. However, space permitting, the publication server
is welcome to keep these files available for longer.
3.4.3. File Format and Validation
Example snapshot file:
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 11]
Internet-Draft RPKI Repository Delta Protocol December 2014
<delta xmlns="HTTP://www.ripe.net/rpki/rrdp" version="1" session_id="9df4b597-af9e-4dca-bdda-719cce2c4e28" serial="5932">
<publish uri="rsync://bandito.ripe.net/repo/3a87a4b1-6e22-4a63-ad0f-06f83ad3ca16/default/671570f06499fbd2d6ab76c4f22566fe49d5de60.mft" hash="226AB8CD3C887A6EBDDDF317F2FAFC9CF3EFC5D43A86347AC0FEFFE4DC0F607E">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</publish>
<publish uri="rsync://bandito.ripe.net/repo/3a87a4b1-6e22-4a63-ad0f-06f83ad3ca16/default/671570f06499fbd2d6ab76c4f22566fe49d5de60.crl" hash="2B551A6C10CCA04C174B0CEB3B64652A5534D1385BEAA40A55A68CB06055E6BB">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</publish>
<withdraw uri="rsync://bandito.ripe.net/repo/3a87a4b1-6e22-4a63-ad0f-06f83ad3ca16/default/example.roa" hash="2B551A6C10CCA04C174B0CEB3B64652A5534D1385BEAA40A55A68CB06055E6BB"/>
</delta>
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 12]
Internet-Draft RPKI Repository Delta Protocol December 2014
Note that a formal RELAX NG specification of this file format is
included later in this document. A RP MUST NOT process any update
notification file that is incomplete or not well formed.
The following validation rules must be observed when creating or
parsing snapshot files:
o A RP MUST NOT process any delta file that is not well formed, or
which does not conform to the RELAX NG schema outlined in Section
5 of this document.
o The XML namespace MUST be HTTP://www.ripe.net/rpki/rrdp.
o The encoding MUST be us-ascii.
o The version attribute in the notification root element MUST be 1
o The session_id attribute MUST be a random version 4 UUID unique to
this session
o The session_id attribute MUST match the expected session_id in the
reference in the notification file.
o The serial attribute MUST match the expected serial in the
reference in the notification file.
o The hexadecimal encoding of the SHA-256 hash of this snapshot file
MUST match the hash attribute in the reference in the notification
file.
o A publish element MUST include a hash attribute, if the object is
intended to replace another object in the RPKI, and its value MUST
be the hexadecimal encoding of the SHA-256 hash of the replaced
object. If the published object does not replace another object
the hash attribute MUST NOT be included. Note that this is an
extension to the publication protocol that is not, yet, reflected
in [I-D.ietf-sidr-publication].
o Similarly a withdraw element MUST contain a hash attribute with
the hexadecimal encoding of the SHA-256 hash of the withdrawn
object. Including the hashes in this manner allows relying
parties to identify specific objects by their hash rather than the
URI where they are found.
3.5. SIA for CA certificates
Certificate Authorities that use this delta protocol MUST have an
instance of an SIA AccessDescription in addition to the ones defined
in [RFC6487],
AccessDescription ::= SEQUENCE {
accessMethod OBJECT IDENTIFIER,
accessLocation GeneralName }
This extension MUST use an accessMethod of id-ad-rpkiNotify, see:
[IANA-AD-NUMBERS],
id-ad OBJECT IDENTIFIER ::= { id-pkix 48 }
id-ad-rpkiNotify OBJECT IDENTIFIER ::= { id-ad 13 }
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 13]
Internet-Draft RPKI Repository Delta Protocol December 2014
The accessLocation MUST be a URI [RFC3986], using the 'HTTP' or
'HTTPS' protocol, that will point to the update notification file for
the publication server that publishes the products of this CA
certificate.
Relying Parties that do not support this delta protocol MUST MUST NOT
reject a CA certificate merely because it has an SIA extension
containing this new kind of AccessDescription.
4. Relying Party Use
4.1. Full Synchronisation
When a Relying Party first encounters a notification file URI as an
SIA of a certificate that it has validated it SHOULD retrieve the
notification file and download the latest snapshot to get in sync
with the current version of the publication server.
The RP SHOULD reject the snapshot file and raise an operator alert,
if its hash does not match the hash listed in the notification file.
However, if the RP does not have any prior state it may choose to
process this snapshot file anyway. It should be noted that the RPKI
objects are protected by object security, so problems or attacks on
the publication server or transport can result in witholding or
replaying old objects, but it cannot force the RP to accept invalid
objects. Using the remaining or old objects for validation is
probably better than rejecting everything, since the latter could be
used as a denial of service vector on relying parties.
4.2. Processing Deltas
It is RECOMMENDED that the RP notes the URI, session_id and serial
number when it first learns about a notification file. The RP MAY
then poll the file to discover updates. How frequently the RP does
this is largely up to local policy. The polling frequency determines
in part what propogation time that a RP is willing to accept between
the moment that a change is published in the RPKI, and the moment
that those changes are processed and validated. As discussed in
Section 3.2.2 there does not seem to be a need to have a propogation
time that is below five minutes. Since the publication server
infrastructure MAY cache the notification file for up to five minutes
a slightly more frequent polling strategy may be useful, however the
RP SHOULD NOT poll more frequently than once per minute. More
frequent polling would only result in marginal gains in propagation,
while causing unnecessary load on the caching infrastructure.
If the RP finds that the session_id has changed, or if it cannot find
a contiguous chain of links to delta files from its current serial to
publication server's current serial, then it MUST perform a full
synchronisation instead of continuing to process deltas.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 14]
Internet-Draft RPKI Repository Delta Protocol December 2014
If the RP finds a contiguous chain of links to delta files from its
current serial to the publication server's current serial, and the
session_id has not changed, it should download all missing delta
files. If any delta file cannot be downloaded, or its hash does not
match the hash listed on the notification file, or if no such chain
of deltas is availabe, or the session_id has changed, then the RP
MUST perform a full synchronisation instead.
New objects found in delta files can be added to the RPs local copy
of the repository. However, it is RECOMMENDED that the RP treats
object updates and withdraws with some skepticism. A compromised
publication server may not have access to the certification
authorities' keys, but it can pretend valid objects have been
withdrawn. Therefore it may be preferred to use a strategy where
local copies of objects are only discarded when the RP is sure that
they are no longer relevant, e.g. the CA has explicitly revoked
them, removed the objects from a valid manifest that it issued, or
they have expired.
5. XML Schema
The following is a RELAX NG compact form schema describing version 1
of this protocol.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 15]
Internet-Draft RPKI Repository Delta Protocol December 2014
#
# RelaxNG schema for RPKI Repository Delta Protocol (RRDP).
#
default namespace = "HTTP://www.ripe.net/rpki/rrdp"
version = xsd:positiveInteger { maxInclusive="1" }
serial = xsd:nonNegativeInteger
uri = xsd:anyURI
uuid = xsd:string { pattern = "[\-0-9a-fA-F]+" }
hash = xsd:string { pattern = "[0-9a-fA-F]+" }
base64 = xsd:base64Binary
# Notification file: lists current snapshots and deltas
start |= element notification {
attribute version { version },
attribute session_id { uuid },
attribute serial { serial },
element snapshot {
attribute uri { uri },
attribute hash { hash }
},
element delta {
attribute serial { serial },
attribute uri { uri },
attribute hash { hash }
}*
}
# Snapshot segment: think DNS AXFR.
start |= element snapshot {
attribute version { version },
attribute session_id { uuid },
attribute serial { serial },
element publish {
attribute uri { uri },
base64
}*
}
# Delta segment: think DNS IXFR.
start |= element delta {
attribute version { version },
attribute session_id { uuid },
attribute serial { serial },
delta_element+
}
delta_element |= element publish {
attribute uri { uri },
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 16]
Internet-Draft RPKI Repository Delta Protocol December 2014
attribute hash { hash }?,
base64
}
delta_element |= element withdraw {
attribute uri { uri },
attribute hash { hash }
}
# Local Variables:
# indent-tabs-mode: nil
# comment-start: "# "
# comment-start-skip: "#[ \t]*"
# End:
6. Security Considerations
TBD
7. IANA Considerations
This document has no actions for IANA.
8. Acknowledgements
TBD
9. References
[I-D.ietf-sidr-publication]
Weiler, S., Sonalker, A. and R. Austein, "A Publication
Protocol for the Resource Public Key Infrastructure
(RPKI)", Internet-Draft draft-ietf-sidr-publication-05,
February 2014.
[IANA-AD-NUMBERS]
"SMI Security for PKIX Access Descriptor", , <http://
www.iana.org/assignments/smi-numbers/smi-numbers.xhtml
#smi-numbers-1.3.6.1.5.5.7.48>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3986] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, RFC
3986, January 2005.
[RFC6481] Huston, G., Loomans, R. and G. Michaelson, "A Profile for
Resource Certificate Repository Structure", RFC 6481,
February 2012.
[RFC6486] Austein, R., Huston, G., Kent, S. and M. Lepinski,
"Manifests for the Resource Public Key Infrastructure
(RPKI)", RFC 6486, February 2012.
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 17]
Internet-Draft RPKI Repository Delta Protocol December 2014
[RFC6487] Huston, G., Michaelson, G. and R. Loomans, "A Profile for
X.509 PKIX Resource Certificates", RFC 6487, February
2012.
[RFC6488] Lepinski, M., Chi, A. and S. Kent, "Signed Object Template
for the Resource Public Key Infrastructure (RPKI)", RFC
6488, February 2012.
Authors' Addresses
Tim Bruijnzeels
RIPE NCC
Email: tim@ripe.net
Oleg Muravskiy
RIPE NCC
Email: oleg@ripe.net
Bryan Weber
Cobenian
Email: bryan@cobenian.com
Rob Austein
Dragon Research Labs
Email: sra@hactrn.net
David Mandelberg
BBN Technologies
Email: david@mandelberg.org
Bruijnzeels, Muravskiy, WExpiresuJunen23,M2015 [Page 18]
