draft-ietf-sidr-bgpsec-protocol-11.txt   draft-ietf-sidr-bgpsec-protocol-12.txt 
Network Working Group M. Lepinski, Ed. Network Working Group M. Lepinski, Ed.
Internet-Draft BBN Internet-Draft BBN
Intended status: Standards Track January 19, 2015 Intended status: Standards Track June 15, 2015
Expires: July 19, 2015, 2015 Expires: December 16, 2015
BGPsec Protocol Specification BGPsec Protocol Specification
draft-ietf-sidr-bgpsec-protocol-11 draft-ietf-sidr-bgpsec-protocol-12
Abstract Abstract
This document describes BGPsec, an extension to the Border Gateway This document describes BGPsec, an extension to the Border Gateway
Protocol (BGP) that provides security for the path of autonomous Protocol (BGP) that provides security for the path of autonomous
systems through which a BGP update message passes. BGPsec is systems through which a BGP update message passes. BGPsec is
implemented via a new optional non-transitive BGP path attribute that implemented via a new optional non-transitive BGP path attribute that
carries a digital signature produced by each autonomous system that carries a digital signature produced by each autonomous system that
propagates the update message. propagates the update message.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" are to be interpreted as described in RFC 2119 [1] only "OPTIONAL" are to be interpreted as described in RFC 2119 [1] only
when they appear in all upper case. They may also appear in lower or when they appear in all upper case. They may also appear in lower or
mixed case as English words, without normative meaning mixed case as English words, without normative meaning.
Status of this Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on January 5, 2015. This Internet-Draft will expire on December 16, 2015.
Copyright Notice Copyright Notice
Copyright (c) 2014 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. BGPsec Negotiation . . . . . . . . . . . . . . . . . . . . . . 3 2. BGPsec Negotiation . . . . . . . . . . . . . . . . . . . . . . 3
2.1. The BGPsec Capability . . . . . . . . . . . . . . . . . . 3 2.1. The BGPsec Capability . . . . . . . . . . . . . . . . . . 3
2.2. Negotiating BGPsec Support . . . . . . . . . . . . . . . . 4 2.2. Negotiating BGPsec Support . . . . . . . . . . . . . . . . 4
3. The BGPsec_Path Attribute . . . . . . . . . . . . . . . . . . 5 3. The BGPsec_Path Attribute . . . . . . . . . . . . . . . . . . 6
3.1. Secure_Path . . . . . . . . . . . . . . . . . . . . . . . 7 3.1. Secure_Path . . . . . . . . . . . . . . . . . . . . . . . 7
3.2. Signature_Block . . . . . . . . . . . . . . . . . . . . . 8 3.2. Signature_Block . . . . . . . . . . . . . . . . . . . . . 8
4. Generating a BGPsec Update . . . . . . . . . . . . . . . . . . 10 4. Generating a BGPsec Update . . . . . . . . . . . . . . . . . . 11
4.1. Originating a New BGPsec Update . . . . . . . . . . . . . 11 4.1. Originating a New BGPsec Update . . . . . . . . . . . . . 12
4.2. Propagating a Route Advertisement . . . . . . . . . . . . 13 4.2. Propagating a Route Advertisement . . . . . . . . . . . . 15
4.3. Processing Instructions for Confederation Members . . . . 17 4.3. Processing Instructions for Confederation Members . . . . 19
4.4. Reconstructing the AS_PATH Attribute . . . . . . . . . . . 19 4.4. Reconstructing the AS_PATH Attribute . . . . . . . . . . . 21
5. Processing a Received BGPsec Update . . . . . . . . . . . . . 20 5. Processing a Received BGPsec Update . . . . . . . . . . . . . 22
5.1. Overview of BGPsec Validation . . . . . . . . . . . . . . 22 5.1. Overview of BGPsec Validation . . . . . . . . . . . . . . 25
5.2. Validation Algorithm . . . . . . . . . . . . . . . . . . . 23 5.2. Validation Algorithm . . . . . . . . . . . . . . . . . . . 26
6. Algorithms and Extensibility . . . . . . . . . . . . . . . . . 27 6. Algorithms and Extensibility . . . . . . . . . . . . . . . . . 30
6.1. Algorithm Suite Considerations . . . . . . . . . . . . . . 27 6.1. Algorithm Suite Considerations . . . . . . . . . . . . . . 30
6.2. Extensibility Considerations . . . . . . . . . . . . . . . 27 6.2. Extensibility Considerations . . . . . . . . . . . . . . . 30
7. Security Considerations . . . . . . . . . . . . . . . . . . . 28 7. Security Considerations . . . . . . . . . . . . . . . . . . . 31
7.1 Security Guarantees . . . . . . . . . . . . . . . . . . . . 28 7.1 Security Guarantees . . . . . . . . . . . . . . . . . . . . 31
7.2 On the Removal of BGPsec Signatures . . . . . . . . . . . . 29 7.2 On the Removal of BGPsec Signatures . . . . . . . . . . . . 32
7.3 Mitigation of Denial of Service Attacks . . . . . . . . . . 30 7.3 Mitigation of Denial of Service Attacks . . . . . . . . . . 34
7.4 Additional Security Considerations . . . . . . . . . . . . . 31 7.4 Additional Security Considerations . . . . . . . . . . . . . 34
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 31 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 35
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 32 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 36
9.1. Authors . . . . . . . . . . . . . . . . . . . . . . . . . 32 9.1. Authors . . . . . . . . . . . . . . . . . . . . . . . . . 36
9.2. Acknowledgements . . . . . . . . . . . . . . . . . . . . . 32 9.2. Acknowledgements . . . . . . . . . . . . . . . . . . . . . 36
10. Normative References . . . . . . . . . . . . . . . . . . . . 33 10. Normative References . . . . . . . . . . . . . . . . . . . . 37
11. Informative References . . . . . . . . . . . . . . . . . . . 33 11. Informative References . . . . . . . . . . . . . . . . . . . 37
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 34 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 38
1. Introduction 1. Introduction
This document describes BGPsec, a mechanism for providing path This document describes BGPsec, a mechanism for providing path
security for Border Gateway Protocol (BGP) [2] route advertisements. security for Border Gateway Protocol (BGP) [2] route advertisements.
That is, a BGP speaker who receives a valid BGPsec update has That is, a BGP speaker who receives a valid BGPsec update has
cryptographic assurance that the advertised route has the following cryptographic assurance that the advertised route has the following
property: Every AS on the path of ASes listed in the update message property: Every AS on the path of ASes listed in the update message
has explicitly authorized the advertisement of the route to the has explicitly authorized the advertisement of the route to the
subsequent AS in the path. subsequent AS in the path.
This document specifies a new optional (non-transitive) BGP path This document specifies a new optional (non-transitive) BGP path
attribute, BGPsec_Path. It also describes how a BGPsec-compliant BGP attribute, BGPsec_Path. It also describes how a BGPsec-compliant BGP
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propagate, and validate BGP update messages containing this attribute propagate, and validate BGP update messages containing this attribute
to obtain the above assurances. to obtain the above assurances.
BGPsec is intended to be used to supplement BGP Origin Validation BGPsec is intended to be used to supplement BGP Origin Validation
[19] and when used in conjunction with origin validation, it is [19] and when used in conjunction with origin validation, it is
possible to prevent a wide variety of route hijacking attacks against possible to prevent a wide variety of route hijacking attacks against
BGP. BGP.
BGPsec relies on the Resource Public Key Infrastructure (RPKI) BGPsec relies on the Resource Public Key Infrastructure (RPKI)
certificates that attest to the allocation of AS number and IP certificates that attest to the allocation of AS number and IP
address resources. (For more information on the RPKI, see [7] and address resources. (For more information on the RPKI, see [12] and
the documents referenced therein.) Any BGPsec speaker who wishes to the documents referenced therein.) Any BGPsec speaker who wishes to
send, to external (eBGP) peers, BGP update messages containing the send, to external (eBGP) peers, BGP update messages containing the
BGPsec_Path needs to possess a private key associated with an RPKI BGPsec_Path needs to possess a private key associated with an RPKI
router certificate [10] that corresponds to the BGPsec speaker's AS router certificate [9] that corresponds to the BGPsec speaker's AS
number. Note, however, that a BGPsec speaker does not need such a number. Note, however, that a BGPsec speaker does not need such a
certificate in order to validate received update messages containing certificate in order to validate received update messages containing
the BGPsec_Path attribute. the BGPsec_Path attribute.
2. BGPsec Negotiation 2. BGPsec Negotiation
This document defines a new BGP capability [6] that allows a BGP This document defines a new BGP capability [6] that allows a BGP
speaker to advertise to a neighbor the ability to send or to receive speaker to advertise to a neighbor the ability to send or to receive
BGPsec update messages (i.e., update messages containing the BGPsec update messages (i.e., update messages containing the
BGPsec_Path attribute). BGPsec_Path attribute).
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the BGPsec_Path attribute (for a particular address family), a BGP the BGPsec_Path attribute (for a particular address family), a BGP
speaker sends the BGPsec capability with the Direction bit set to 0. speaker sends the BGPsec capability with the Direction bit set to 0.
In order to advertise the capability to both send and receive BGPsec In order to advertise the capability to both send and receive BGPsec
update messages, the BGP speaker sends two copies of the BGPsec update messages, the BGP speaker sends two copies of the BGPsec
capability (one with the direction bit set to 0 and one with the capability (one with the direction bit set to 0 and one with the
direction bit set to 1). direction bit set to 1).
Similarly, if a BGP speaker wishes to use BGPsec with two different Similarly, if a BGP speaker wishes to use BGPsec with two different
address families (i.e., IPv4 and IPv6) over the same BGP session, address families (i.e., IPv4 and IPv6) over the same BGP session,
then the speaker includes two instances of this capability (one for then the speaker includes two instances of this capability (one for
each address family) in the BGP OPEN message. A BGP speaker SHOULD each address family) in the BGP OPEN message. A BGP speaker MUST
NOT advertise the capability of BGPsec support for a particular AFI support the BGP multiprotocol extension [3]. Additionally, a BGP
unless it has also advertised the multiprotocol extension capability speaker MUST NOT advertise the capability of BGPsec support for a
for the same AFI combination [3]. particular AFI unless it has also advertised the multiprotocol
extension capability for the same AFI combination [3].
In a session where BGP session, a peer is permitted to send update In a session where BGP session, a peer is permitted to send update
messages containing the BGPsec_Path attribute if, and only if: messages containing the BGPsec_Path attribute if, and only if:
o The given peer sent the BGPsec capability for a particular version o The given peer sent the BGPsec capability for a particular version
of BGPsec and a particular address family with the Direction bit of BGPsec and a particular address family with the Direction bit
set to 1; and set to 1; and
o The other peer sent the BGPsec capability for the same version of o The other peer sent the BGPsec capability for the same version of
BGPsec and the same address family with the Direction bit set to BGPsec and the same address family with the Direction bit set to
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for four-byte AS numbers. Therefore, any BGP speaker that announces for four-byte AS numbers. Therefore, any BGP speaker that announces
the BGPsec capability, MUST also announce the capability for four- the BGPsec capability, MUST also announce the capability for four-
byte AS support [4]. If a BGP speaker sends the BGPsec capability but byte AS support [4]. If a BGP speaker sends the BGPsec capability but
not the four-byte AS support capability then BGPsec has not been not the four-byte AS support capability then BGPsec has not been
successfully negotiated, and update messages containing the successfully negotiated, and update messages containing the
BGPsec_Path attribute MUST NOT be sent within such a session. BGPsec_Path attribute MUST NOT be sent within such a session.
Note that BGPsec update messages can be quite large, therefore any Note that BGPsec update messages can be quite large, therefore any
BGPsec speaker announcing the capability to receive BGPsec messages BGPsec speaker announcing the capability to receive BGPsec messages
SHOULD also announce support for the capability to receive BGP SHOULD also announce support for the capability to receive BGP
extended messages [9]. extended messages [8].
3. The BGPsec_Path Attribute 3. The BGPsec_Path Attribute
The BGPsec_Path attribute is a new optional non-transitive BGP path The BGPsec_Path attribute is a new optional non-transitive BGP path
attribute. attribute.
This document registers a new attribute type code for this attribute This document registers a new attribute type code for this attribute
: TBD : TBD
The BGPsec_Path attribute carries the secured information regarding The BGPsec_Path attribute carries the secured information regarding
the path of ASes through which an update message passes. This the path of ASes through which an update message passes. This
includes the digital signatures used to protect the path information. includes the digital signatures used to protect the path information.
We refer to those update messages that contain the BGPsec_Path We refer to those update messages that contain the BGPsec_Path
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+---------------------------------------------+ +---------------------------------------------+
The Signature_Block Length is the total number of octets in the The Signature_Block Length is the total number of octets in the
Signature_Block (including the two octets used to express this length Signature_Block (including the two octets used to express this length
field). field).
The Algorithm Suite Identifier is a one-octet identifier specifying The Algorithm Suite Identifier is a one-octet identifier specifying
the digest algorithm and digital signature algorithm used to produce the digest algorithm and digital signature algorithm used to produce
the digital signature in each Signature Segment. An IANA registry of the digital signature in each Signature Segment. An IANA registry of
algorithm identifiers for use in BGPsec is specified in the BGPsec algorithm identifiers for use in BGPsec is specified in the BGPsec
algorithms document [11]. algorithms document [10].
A Signature_Block has exactly one Signature Segment for each A Signature_Block has exactly one Signature Segment for each
Secure_Path Segment in the Secure_Path portion of the BGPsec_Path Secure_Path Segment in the Secure_Path portion of the BGPsec_Path
Attribute. (That is, one Signature Segment for each distinct AS on Attribute. (That is, one Signature Segment for each distinct AS on
the path for the NLRI in the Update message.) the path for the NLRI in the Update message.)
Signature Segments Signature Segments
+---------------------------------------------+ +---------------------------------------------+
| Subject Key Identifier (20 octets) | | Subject Key Identifier (20 octets) |
+---------------------------------------------+ +---------------------------------------------+
| Signature Length (2 octets) | | Signature Length (2 octets) |
+---------------------------------------------+ +---------------------------------------------+
| Signature (variable) | | Signature (variable) |
+---------------------------------------------+ +---------------------------------------------+
The Subject Key Identifier contains the value in the Subject Key The Subject Key Identifier contains the value in the Subject Key
Identifier extension of the RPKI router certificate [10] that is used Identifier extension of the RPKI router certificate [9] that is used
to verify the signature (see Section 5 for details on validity of to verify the signature (see Section 5 for details on validity of
BGPsec update messages). BGPsec update messages).
The Signature Length field contains the size (in octets) of the value The Signature Length field contains the size (in octets) of the value
in the Signature field of the Signature Segment. in the Signature field of the Signature Segment.
The Signature contains a digital signature that protects the NLRI and The Signature contains a digital signature that protects the NLRI and
the BGPsec_Path attribute (see Sections 4 and 5 for details on the BGPsec_Path attribute (see Sections 4 and 5 for details on
signature generation and validation, respectively). signature generation and validation, respectively).
4. Generating a BGPsec Update 4. Generating a BGPsec Update
Sections 4.1 and 4.2 cover two cases in which a BGPsec speaker may Sections 4.1 and 4.2 cover two of the cases in which a BGPsec speaker
generate an update message containing the BGPsec_Path attribute. The generates an update message containing the BGPsec_Path attribute.
first case is that in which the BGPsec speaker originates a new route The first case is that in which the BGPsec speaker originates a new
advertisement (Section 4.1). That is, the BGPsec speaker is route advertisement (Section 4.1). That is, the BGPsec speaker is
constructing an update message in which the only AS to appear in the constructing an update message in which the only AS to appear in the
BGPsec_Path is the speaker's own AS. The second case is that in BGPsec_Path is the speaker's own AS. The second case is that in
which the BGPsec speaker receives a route advertisement from a peer which the BGPsec speaker receives a route advertisement from a peer
and then decides to propagate the route advertisement to an external and then decides to propagate the route advertisement to an external
(eBGP) peer (Section 4.2). That is, the BGPsec speaker has received (eBGP) peer (Section 4.2). That is, the BGPsec speaker has received
a BGPsec update message and is constructing a new update message for a BGPsec update message and is constructing a new update message for
the same NLRI in which the BGPsec_Path attribute will contain AS the same NLRI in which the BGPsec_Path attribute will contain AS
number(s) other than the speaker's own AS. number(s) other than the speaker's own AS.
The remaining case is where the BGPsec speaker sends the update The remaining case is where the BGPsec speaker sends the update
message to an internal (iBGP) peer. When originating a new route message to an internal (iBGP) peer. When originating a new route
advertisement and sending it to an internal peer, the BGPsec speaker advertisement and sending it to an internal peer, the BGPsec speaker
omits the BGPsec_Path attribute. When propagating a received route omits the BGPsec_Path attribute. When propagating a received route
advertisement to an internal peer, the BGPsec speaker populates the advertisement to an internal peer, the BGPsec speaker typically
BGPsec_Path attribute by copying the BGPsec_Path attribute from the populates the BGPsec_Path attribute by copying the BGPsec_Path
received update message. That is, the BGPsec_Path attribute is attribute from the received update message. That is, the BGPsec_Path
copied verbatim. Note that in the case that a BGPsec speaker chooses attribute is copied verbatim. However, in the case that the BGPsec
to forward to an iBGP peer a BGPsec update message that has not been speaker is performing an AS Migration, the BGPsec speaker may add an
successfully validated (see Section 5), the BGPsec_Path attribute additional signature on ingress before copying the BGPsec_Path
SHOULD NOT be removed. (See Section 7 for the security ramifications attribute (see [18] for more details).
of removing BGPsec signatures.)
Note that when a BGPsec speaker chooses to forward a BGPsec update
message to an iBGP peer, the BGPsec attribute SHOULD NOT be removed,
unless the peer doesn't support BGPsec. In particular, the BGPsec
attribute SHOULD NOT be removed even in the case where the BGPsec
update message has not been that has not successfully validated. (See
Section 5 for more information on validation, and Section 7 for the
security ramifications of removing BGPsec signatures.)
The information protected by the signature on a BGPsec update message The information protected by the signature on a BGPsec update message
includes the AS number of the peer to whom the update message is includes the AS number of the peer to whom the update message is
being sent. Therefore, if a BGPsec speaker wishes to send a BGPsec being sent. Therefore, if a BGPsec speaker wishes to send a BGPsec
update to multiple BGP peers, it MUST generate a separate BGPsec update to multiple BGP peers, it MUST generate a separate BGPsec
update message for each unique peer AS to which the update message is update message for each unique peer AS to whom the update message is
sent. sent.
A BGPsec update message MUST advertise a route to only a single NLRI. A BGPsec update message MUST advertise a route to only a single NLRI.
This is because a BGPsec speaker receiving an update message with This is because a BGPsec speaker receiving an update message with
multiple NLRI would be unable to construct a valid BGPsec update multiple NLRI would be unable to construct a valid BGPsec update
message (i.e., valid path signatures) containing a subset of the NLRI message (i.e., valid path signatures) containing a subset of the NLRI
in the received update. If a BGPsec speaker wishes to advertise in the received update. If a BGPsec speaker wishes to advertise
routes to multiple NLRI, then it MUST generate a separate BGPsec routes to multiple NLRI, then it MUST generate a separate BGPsec
update message for each NLRI. update message for each NLRI. Additionally, a BGPsec update message
MUST use the MP_REACH_NLRI [3] attribute to encode the NLRI.
In order to create or add a new signature to a BGPsec update message In order to create or add a new signature to a BGPsec update message
with a given algorithm suite, the BGPsec speaker must possess a with a given algorithm suite, the BGPsec speaker must possess a
private key suitable for generating signatures for this algorithm private key suitable for generating signatures for this algorithm
suite. Additionally, this private key must correspond to the public suite. Additionally, this private key must correspond to the public
key in a valid Resource PKI end-entity certificate whose AS number key in a valid Resource PKI end-entity certificate whose AS number
resource extension includes the BGPsec speaker's AS number [10]. Note resource extension includes the BGPsec speaker's AS number [9]. Note
also that new signatures are only added to a BGPsec update message also that new signatures are only added to a BGPsec update message
when a BGPsec speaker is generating an update message to send to an when a BGPsec speaker is generating an update message to send to an
external peer (i.e., when the AS number of the peer is not equal to external peer (i.e., when the AS number of the peer is not equal to
the BGPsec speaker's own AS number). Therefore, a BGPsec speaker who the BGPsec speaker's own AS number). Therefore, a BGPsec speaker who
only sends BGPsec update messages to peers within its own AS, it does only sends BGPsec update messages to peers within its own AS, it does
not need to possess any private signature keys. not need to possess any private signature keys.
Section 4.3 contains special processing instructions for members of Section 4.3 contains special processing instructions for members of
an autonomous system confederation [5]. A BGPsec speaker that is not an autonomous system confederation [5]. A BGPsec speaker that is not
a member of such a confederation MUST set the Flags field of the a member of such a confederation MUST set the Flags field of the
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In an update message that originates a new route advertisement (i.e., In an update message that originates a new route advertisement (i.e.,
an update whose path will contain only a single AS number), when an update whose path will contain only a single AS number), when
sending the route advertisement to an external, BGPsec-speaking peer, sending the route advertisement to an external, BGPsec-speaking peer,
the BGPsec speaker creates a new BGPsec_Path attribute as follows. the BGPsec speaker creates a new BGPsec_Path attribute as follows.
First, the BGPsec speaker constructs the Secure_Path with a single First, the BGPsec speaker constructs the Secure_Path with a single
Secure_Path Segment. The AS in this path is the BGPsec speaker's own Secure_Path Segment. The AS in this path is the BGPsec speaker's own
AS number. In particular, this AS number MUST match an AS number in AS number. In particular, this AS number MUST match an AS number in
the AS number resource extension field of the Resource PKI router the AS number resource extension field of the Resource PKI router
certificate(s) [10] that will be used to verify the digital certificate(s) [9] that will be used to verify the digital
signature(s) constructed by this BGPsec speaker. signature(s) constructed by this BGPsec speaker.
The BGPsec_Path attribute and the AS_Path attribute are mutually The BGPsec_Path attribute and the AS_Path attribute are mutually
exclusive. That is, any update message containing the BGPsec_Path exclusive. That is, any update message containing the BGPsec_Path
attribute MUST NOT contain the AS_Path attribute. The information attribute MUST NOT contain the AS_Path attribute. The information
that would be contained in the AS_Path attribute is instead conveyed that would be contained in the AS_Path attribute is instead conveyed
in the Secure_Path portion of the BGPsec_Path attribute. in the Secure_Path portion of the BGPsec_Path attribute.
The Resource PKI enables the legitimate holder of IP address The Resource PKI enables the legitimate holder of IP address
prefix(es) to issue a signed object, called a Route Origination prefix(es) to issue a signed object, called a Route Origination
Authorization (ROA), that authorizes a given AS to originate routes Authorization (ROA), that authorizes a given AS to originate routes
to a given set of prefixes (see [8]). It is expected that most to a given set of prefixes (see [7]). It is expected that most
relying parties will utilize BGPsec in tandem with origin validation relying parties will utilize BGPsec in tandem with origin validation
(see [19] and [20]). Therefore, it is RECOMMENDED that a BGPsec (see [19] and [20]). Therefore, it is RECOMMENDED that a BGPsec
speaker only originate a BGPsec update advertising a route for a speaker only originate a BGPsec update advertising a route for a
given prefix if there exists a valid ROA authorizing the BGPsec given prefix if there exists a valid ROA authorizing the BGPsec
speaker's AS to originate routes to this prefix. speaker's AS to originate routes to this prefix.
The pCount field of the Secure_Path Segment is typically set to the The pCount field of the Secure_Path Segment is typically set to the
value 1. However, a BGPsec speaker may set the pCount field to a value 1. However, a BGPsec speaker may set the pCount field to a
value greater than 1. Setting the pCount field to a value greater value greater than 1. Setting the pCount field to a value greater
than one has the same semantics as repeating an AS number multiple than one has the same semantics as repeating an AS number multiple
skipping to change at page 12, line 28 skipping to change at page 13, line 35
algorithm suite, it will be necessary to originate update messages algorithm suite, it will be necessary to originate update messages
that contain a Signature_Block for both the 'current' and the 'new' that contain a Signature_Block for both the 'current' and the 'new'
algorithm suites (see Section 6.1). algorithm suites (see Section 6.1).
When originating a new route advertisement, each Signature_Block MUST When originating a new route advertisement, each Signature_Block MUST
consist of a single Signature Segment. The following describes how consist of a single Signature Segment. The following describes how
the BGPsec speaker populates the fields of the Signature_Block. the BGPsec speaker populates the fields of the Signature_Block.
The Subject Key Identifier field (see Section 3) is populated with The Subject Key Identifier field (see Section 3) is populated with
the identifier contained in the Subject Key Identifier extension of the identifier contained in the Subject Key Identifier extension of
the RPKI router certificate corresponding to the BGPsec speaker[10]. the RPKI router certificate corresponding to the BGPsec speaker [9].
This Subject Key Identifier will be used by recipients of the route This Subject Key Identifier will be used by recipients of the route
advertisement to identify the proper certificate to use in verifying advertisement to identify the proper certificate to use in verifying
the signature. the signature.
The Signature field contains a digital signature that binds the NLRI The Signature field contains a digital signature that binds the NLRI
and BGPsec_Path attribute to the RPKI router certificate and BGPsec_Path attribute to the RPKI router certificate
corresponding to the BGPsec speaker. The digital signature is corresponding to the BGPsec speaker. The digital signature is
computed as follows: computed as follows:
o Construct a sequence of octets by concatenating the Target AS o Construct a sequence of octets by concatenating the Target AS
Number, the Secure_Path (Origin AS, pCount, and Flags), Algorithm Number, the Secure_Path (Origin AS, pCount, and Flags), Algorithm
Suite Identifier, and NLRI. The Target AS Number is the AS to Suite Identifier, and the MP_REACH_NLRI attribute. The Target AS
whom the BGPsec speaker intends to send the update message. (Note Number is the AS to whom the BGPsec speaker intends to send the
that the Target AS number is the AS number announced by the peer update message. (Note that the Target AS number is the AS number
in the OPEN message of the BGP session within which the update is announced by the peer in the OPEN message of the BGP session
sent.) within which the update is sent.) Additionally, in the Prefix
field of the NLRI within the MP_REACH_NLRI attribute, all of the
trailing bits MUST be set to zero when constructing this
sequence.
Sequence of Octets to be Signed Sequence of Octets to be Signed
+------------------------------------+ +------------------------------------+
| Target AS Number (4 octets) | | Target AS Number (4 octets) |
+------------------------------------+ +------------------------------------+
| Origin AS Number (4 octets) | ---\ | Origin AS Number (4 octets) | ---\
+------------------------------------+ \ +------------------------------------+ \
| pCount (1 octet) | > Secure_Path | pCount (1 octet) | > Secure_Path
+------------------------------------+ / +------------------------------------+ /
| Flags (1 octet) | ---/ | Flags (1 octet) | ---/
+------------------------------------+ +------------------------------------+
| Algorithm Suite Id. (1 octet) | | Algorithm Suite Id. (1 octet) |
+------------------------------------+ +------------------------------------+
| NLRI Length (1 octet) | | MP_REACH_NLRI (variable) |
+------------------------------------+
| NLRI Prefix (variable) |
+------------------------------------+ +------------------------------------+
o Apply to this octet sequence the digest algorithm (for the o Apply to this octet sequence the digest algorithm (for the
algorithm suite of this Signature_Block) to obtain a digest value. algorithm suite of this Signature_Block) to obtain a digest value.
o Apply to this digest value the signature algorithm, (for the o Apply to this digest value the signature algorithm, (for the
algorithm suite of this Signature_Block) to obtain the digital algorithm suite of this Signature_Block) to obtain the digital
signature. Then populate the Signature Field with this digital signature. Then populate the Signature Field with this digital
signature. signature.
skipping to change at page 14, line 40 skipping to change at page 16, line 38
BGPsec) update message. It should be noted that BCP 172 [13] BGPsec) update message. It should be noted that BCP 172 [13]
recommends against the use of AS_SET and AS_CONFED_SET in the AS_PATH recommends against the use of AS_SET and AS_CONFED_SET in the AS_PATH
of BGP updates. of BGP updates.
To generate the BGPsec_Path attribute on the outgoing update message, To generate the BGPsec_Path attribute on the outgoing update message,
the BGPsec speaker first prepends a new Secure_Path Segment (places the BGPsec speaker first prepends a new Secure_Path Segment (places
in first position) to the Secure_Path. The AS number in this in first position) to the Secure_Path. The AS number in this
Secure_Path segment MUST match the AS number in the AS number Secure_Path segment MUST match the AS number in the AS number
resource extension field of the Resource PKI router certificate(s) resource extension field of the Resource PKI router certificate(s)
that will be used to verify the digital signature(s) constructed by that will be used to verify the digital signature(s) constructed by
this BGPsec speaker[10]. this BGPsec speaker [9].
The pCount is typically set to the value 1. A BGPsec speaker may set The pCount is typically set to the value 1. A BGPsec speaker may set
the pCount field to a value greater than 1. (See Section 4.1 for a the pCount field to a value greater than 1. (See Section 4.1 for a
discussion of setting pCount to a value greater than 1.) discussion of setting pCount to a value greater than 1.)
A route server that participates in the BGP control path, but does A route server that participates in the BGP control path, but does
not act as a transit AS in the data plane, may choose to set pCount not act as a transit AS in the data plane, may choose to set pCount
to 0. This option enables the route server to participate in BGPsec to 0. This option enables the route server to participate in BGPsec
and obtain the associated security guarantees without increasing the and obtain the associated security guarantees without increasing the
effective length of the AS path. (Note that BGPsec speakers compute effective length of the AS path. (Note that BGPsec speakers compute
skipping to change at page 15, line 51 skipping to change at page 17, line 49
For each Signature_Block corresponding to an algorithm suite that the For each Signature_Block corresponding to an algorithm suite that the
BGPsec speaker does support, the BGPsec speaker adds a new Signature BGPsec speaker does support, the BGPsec speaker adds a new Signature
Segment to the Signature_Block. This Signature Segment is prepended Segment to the Signature_Block. This Signature Segment is prepended
to the list of Signature Segments (placed in the first position) so to the list of Signature Segments (placed in the first position) so
that the list of Signature Segments appear in the same order as the that the list of Signature Segments appear in the same order as the
corresponding Secure_Path segments. The BGPsec speaker populates the corresponding Secure_Path segments. The BGPsec speaker populates the
fields of this new signature segment as follows. fields of this new signature segment as follows.
The Subject Key Identifier field in the new segment is populated with The Subject Key Identifier field in the new segment is populated with
the identifier contained in the Subject Key Identifier extension of the identifier contained in the Subject Key Identifier extension of
the RPKI router certificate corresponding to the BGPsec speaker [10]. the RPKI router certificate corresponding to the BGPsec speaker [9].
This Subject Key Identifier will be used by recipients of the route This Subject Key Identifier will be used by recipients of the route
advertisement to identify the proper certificate to use in verifying advertisement to identify the proper certificate to use in verifying
the signature. the signature.
The Signature field in the new segment contains a digital signature The Signature field in the new segment contains a digital signature
that binds the NLRI and BGPsec_Path attribute to the RPKI router that binds the NLRI and BGPsec_Path attribute to the RPKI router
certificate corresponding to the BGPsec speaker. The digital certificate corresponding to the BGPsec speaker. The digital
signature is computed as follows: signature is computed as follows:
o Construct a sequence of octets by concatenating the Target AS o Construct a sequence of octets by concatenating the Target AS
number, the Secure_Path segment that is being added by the BGPsec number, the Secure_Path segment that is being added by the BGPsec
skipping to change at page 19, line 6 skipping to change at page 21, line 6
in the corresponding Secure_Path segment is set to one. If the in the corresponding Secure_Path segment is set to one. If the
Confed_Sequence flag is set to one in the corresponding Secure_Path Confed_Sequence flag is set to one in the corresponding Secure_Path
segment, the confederation member does not perform any further checks segment, the confederation member does not perform any further checks
on the Signature_Segment and immediately moves on to the next on the Signature_Segment and immediately moves on to the next
Signature_Segment (and checks its corresponding Secure_Path segment). Signature_Segment (and checks its corresponding Secure_Path segment).
Note that as specified in Section 5.2, it is an error when a BGPsec Note that as specified in Section 5.2, it is an error when a BGPsec
speaker receives from a peer, who is not in the same AS speaker receives from a peer, who is not in the same AS
confederation, a BGPsec update containing a Confed_Sequence flag set confederation, a BGPsec update containing a Confed_Sequence flag set
to one. (As discussed in Section 5.2, any error in the BGPsec_Path to one. (As discussed in Section 5.2, any error in the BGPsec_Path
attribute MUST be handled using the "treat-as-withdraw", approach as attribute MUST be handled using the "treat-as-withdraw", approach as
defined in RFC WXYZ [12].) defined in RFC WXYZ [11].)
4.4. Reconstructing the AS_PATH Attribute 4.4. Reconstructing the AS_PATH Attribute
BGPsec update messages do not contain the AS_PATH attribute. However, BGPsec update messages do not contain the AS_PATH attribute. However,
the AS_PATH attribute can be reconstructed from the BGPsec_Path the AS_PATH attribute can be reconstructed from the BGPsec_Path
attribute. This is necessary in the case where a route advertisement attribute. This is necessary in the case where a route advertisement
is received via a BGPsec update message and then propagated to a peer is received via a BGPsec update message and then propagated to a peer
via a non-BGPsec update message (e.g., because the latter peer does via a non-BGPsec update message (e.g., because the latter peer does
not support BGPsec). Note that there may be additional cases where an not support BGPsec). Note that there may be additional cases where an
implementation finds it useful to perform this reconstruction. implementation finds it useful to perform this reconstruction.
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Section 5.1 provides an overview of BGPsec validation and Section 5.2 Section 5.1 provides an overview of BGPsec validation and Section 5.2
provides a specific algorithm for performing such validation. (Note provides a specific algorithm for performing such validation. (Note
that an implementation need not follow the specific algorithm in that an implementation need not follow the specific algorithm in
Section 5.2 as long as the input/output behavior of the validation is Section 5.2 as long as the input/output behavior of the validation is
identical to that of the algorithm in Section 5.2.) During identical to that of the algorithm in Section 5.2.) During
exceptional conditions (e.g., the BGPsec speaker receives an exceptional conditions (e.g., the BGPsec speaker receives an
incredibly large number of update messages at once) a BGPsec speaker incredibly large number of update messages at once) a BGPsec speaker
MAY temporarily defer validation of incoming BGPsec update messages. MAY temporarily defer validation of incoming BGPsec update messages.
The treatment of such BGPsec update messages, whose validation has The treatment of such BGPsec update messages, whose validation has
been deferred, is a matter of local policy. been deferred, is a matter of local policy. However, an
implementation SHOULD ensure that deferment of validation and status
of deferred messages is visible to the operator.
The validity of BGPsec update messages is a function of the current The validity of BGPsec update messages is a function of the current
RPKI state. When a BGPsec speaker learns that RPKI state has changed RPKI state. When a BGPsec speaker learns that RPKI state has changed
(e.g., from an RPKI validating cache via the RTR protocol), the (e.g., from an RPKI validating cache via the RTR protocol), the
BGPsec speaker MUST re-run validation on all affected update messages BGPsec speaker MUST re-run validation on all affected update messages
stored in its ADJ-RIB-IN. That is, when a given RPKI certificate stored in its ADJ-RIB-IN. That is, when a given RPKI certificate
ceases to be valid (e.g., it expires or is revoked), all update ceases to be valid (e.g., it expires or is revoked), all update
messages containing a signature whose SKI matches the SKI in the messages containing a signature whose SKI matches the SKI in the
given certificate must be re-assessed to determine if they are still given certificate must be re-assessed to determine if they are still
valid. If this reassessment determines that the validity state of an valid. If this reassessment determines that the validity state of an
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the trusted cache could deliver the necessary validity information to the trusted cache could deliver the necessary validity information to
the BGPsec speaker using the router key PDU [16] for the RTR protocol the BGPsec speaker using the router key PDU [16] for the RTR protocol
[15].) [15].)
To validate a BGPsec update message containing the BGPsec_Path To validate a BGPsec update message containing the BGPsec_Path
attribute, the recipient performs the validation steps specified in attribute, the recipient performs the validation steps specified in
Section 5.2. The validation procedure results in one of two states: Section 5.2. The validation procedure results in one of two states:
'Valid' and 'Not Valid'. 'Valid' and 'Not Valid'.
It is expected that the output of the validation procedure will be It is expected that the output of the validation procedure will be
used as an input to BGP route selection. However, BGP route used as an input to BGP route selection. That said, BGP route
selection, and thus the handling of the two validation states is a selection, and thus the handling of the validation states is a matter
matter of local policy, and is handled using local policy mechanisms. of local policy, and is handled using local policy mechanisms.
Implementations SHOULD enable operators to set such local policy on a
per-session basis. (That is, we expect some operators will choose to
treat BGPSEC validation status differently for update messages
received over different BGP sessions.)
It is expected that BGP peers will generally prefer routes received It is expected that BGP peers will generally prefer routes received
via 'Valid' BGPsec update messages over both routes received via 'Not via 'Valid' BGPsec update messages over both routes received via 'Not
Valid' BGPsec update messages and routes received via update messages Valid' BGPsec update messages and routes received via update messages
that do not contain the BGPsec_Path attribute. However, BGPsec that do not contain the BGPsec_Path attribute. However, BGPsec
specifies no changes to the BGP decision process. (See [17] for specifies no changes to the BGP decision process. (See [17] for
related operational considerations.) related operational considerations.)
BGPsec validation needs only be performed at the eBGP edge. The BGPsec validation needs only be performed at the eBGP edge. The
validation status of a BGP signed/unsigned update MAY be conveyed via validation status of a BGP signed/unsigned update MAY be conveyed via
skipping to change at page 23, line 43 skipping to change at page 26, line 47
that none of the Secure_Path segments contain a Flags field with that none of the Secure_Path segments contain a Flags field with
the Confed_Sequence flag set to one. the Confed_Sequence flag set to one.
5. If the update message was received from a peer that is not 5. If the update message was received from a peer that is not
expected to set pCount equal to zero (see Section 4.2) then check expected to set pCount equal to zero (see Section 4.2) then check
to ensure that the pCount field in the most-recently added to ensure that the pCount field in the most-recently added
Secure_Path segment is not equal to zero. Secure_Path segment is not equal to zero.
If any of these checks fail, it is an error in the BGPsec_Path If any of these checks fail, it is an error in the BGPsec_Path
attribute. Any of these errors in the BGPsec_Path attribute are attribute. Any of these errors in the BGPsec_Path attribute are
handled as per RFC WXYZ [12]. BGPsec speakers MUST handle these handled as per RFC WXYZ [11]. BGPsec speakers MUST handle these
errors using the "treat-as-withdraw" approach as defined in RFC WXYZ errors using the "treat-as-withdraw" approach as defined in RFC WXYZ
[12]. [11].
Next, the BGPsec speaker examines the Signature_Blocks in the Next, the BGPsec speaker examines the Signature_Blocks in the
BGPsec_Path attribute. A Signature_Block corresponding to an BGPsec_Path attribute. A Signature_Block corresponding to an
algorithm suite that the BGPsec speaker does not support is not algorithm suite that the BGPsec speaker does not support is not
considered in validation. If there is no Signature_Block considered in validation. If there is no Signature_Block
corresponding to an algorithm suite that the BGPsec speaker supports, corresponding to an algorithm suite that the BGPsec speaker supports,
then the BGPsec speaker MUST treat the update message in the same then the BGPsec speaker MUST treat the update message in the same
manner that the BGPsec speaker would treat an (unsigned) update manner that the BGPsec speaker would treat an (unsigned) update
message that arrived without a BGPsec_Path attribute. message that arrived without a BGPsec_Path attribute.
skipping to change at page 25, line 17 skipping to change at page 28, line 17
+-------------------------------------------+ +-------------------------------------------+
| AS Number of Target AS (4 octets) | | AS Number of Target AS (4 octets) |
+-------------------------------------------+ +-------------------------------------------+
| AS Number (4 octets) | ---\ | AS Number (4 octets) | ---\
+-------------------------------------------+ \ +-------------------------------------------+ \
| pCount (1 octet) | > Secure_Path | pCount (1 octet) | > Secure_Path
+-------------------------------------------+ / +-------------------------------------------+ /
| Flags (1 octet) | ---/ | Flags (1 octet) | ---/
+-------------------------------------------+ +-------------------------------------------+
| Sig Field in the Next Segment (variable) | | Sig Field in the Next Segment (variable) |
+-------------- ----------------------------+ +-------------------------------------------+
For the first segment to be processed (the most recently added For the first segment to be processed (the most recently added
segment), the 'AS Number of Target AS' is the AS number of the BGPsec segment), the 'AS Number of Target AS' is the AS number of the BGPsec
speaker validating the update message. Note that if a BGPsec speaker speaker validating the update message. Note that if a BGPsec speaker
uses multiple AS Numbers (e.g., the BGPsec speaker is a member of a uses multiple AS Numbers (e.g., the BGPsec speaker is a member of a
confederation), the AS number used here MUST be the AS number confederation), the AS number used here MUST be the AS number
announced in the OPEN message for the BGP session over which the announced in the OPEN message for the BGP session over which the
BGPsec update was received. BGPsec update was received.
For each other Signature Segment, the 'AS Number of Target AS' is the For each other Signature Segment, the 'AS Number of Target AS' is the
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| AS Number of Target AS (4 octets) | | AS Number of Target AS (4 octets) |
+------------------------------------+ +------------------------------------+
| Origin AS Number (4 octets) | ---\ | Origin AS Number (4 octets) | ---\
+------------------------------------+ \ +------------------------------------+ \
| pCount (1 octet) | > Secure_Path | pCount (1 octet) | > Secure_Path
+------------------------------------+ / +------------------------------------+ /
| Flags (1 octet) | ---/ | Flags (1 octet) | ---/
+------------------------------------+ +------------------------------------+
| Algorithm Suite Id. (1 octet) | | Algorithm Suite Id. (1 octet) |
+------------------------------------+ +------------------------------------+
| NLRI Length (1 octet) | | MP_REACH_NLRI (variable) |
+------------------------------------+
| NLRI Prefix (variable) |
+------------------------------------+ +------------------------------------+
The NLRI Length, NLRI Prefix, and Algorithm Suite Identifier are all The MP_REACH_NLRI attribute is obtained from the update message.
obtained in a straight forward manner from the NLRI of the update However, in the Prefix field of the MP_REACH_NLRI attribute, all
message or the BGPsec_Path attribute being validated. The Origin AS trailing bits MUST be set to zero for the purpose of signature
Number, pCount, and Flags fields are taken from the Secure_Path verification. The Algorithm Suite Identifier is obtained from the
segment corresponding to the Signature Segment currently being BGPsec_Path attribute being validated. The Origin AS Number, pCount,
processed. and Flags fields are taken from the Secure_Path segment corresponding
to the Signature Segment currently being processed.
The 'AS Number of Target AS' is the AS Number from the Secure_Path The 'AS Number of Target AS' is the AS Number from the Secure_Path
segment that was added immediately after the Secure_Path segment segment that was added immediately after the Secure_Path segment
containing the Origin AS Number. (That is, the Secure_Path segment containing the Origin AS Number. (That is, the Secure_Path segment
corresponding to the Signature segment that the receiver just corresponding to the Signature segment that the receiver just
finished processing prior to the current Signature segment.) finished processing prior to the current Signature segment.)
o (Step III): Use the signature validation algorithm (for the given o (Step III): Use the signature validation algorithm (for the given
algorithm suite) to verify the signature in the current segment. algorithm suite) to verify the signature in the current segment.
That is, invoke the signature validation algorithm on the That is, invoke the signature validation algorithm on the
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(digest and signature) algorithm suite. This is because the algorithm (digest and signature) algorithm suite. This is because the algorithm
suite used by the sender of a BGPsec update message must be suite used by the sender of a BGPsec update message must be
understood not only by the peer to whom he is directly sending the understood not only by the peer to whom he is directly sending the
message, but also by all BGPsec speakers to whom the route message, but also by all BGPsec speakers to whom the route
advertisement is eventually propagated. Therefore, selection of an advertisement is eventually propagated. Therefore, selection of an
algorithm suite cannot be a local matter negotiated by BGP peers, but algorithm suite cannot be a local matter negotiated by BGP peers, but
instead must be coordinated throughout the Internet. instead must be coordinated throughout the Internet.
To this end, a mandatory algorithm suites document will be created To this end, a mandatory algorithm suites document will be created
which specifies a mandatory-to-use 'current' algorithm suite for use which specifies a mandatory-to-use 'current' algorithm suite for use
by all BGPsec speakers [11]. by all BGPsec speakers [10].
It is anticipated that, in the future mandatory, the algorithm suites We anticipate that, in the future, the mandatory algorithm suites
document will be updated to specify a transition from the 'current' document will be updated to specify a transition from the 'current'
algorithm suite to a 'new' algorithm suite. During the period of algorithm suite to a 'new' algorithm suite. During the period of
transition (likely a small number of years), all BGPsec update transition (likely a small number of years), all BGPsec update
messages SHOULD simultaneously use both the 'current' algorithm suite messages SHOULD simultaneously use both the 'current' algorithm suite
and the 'new' algorithm suite. (Note that Sections 3 and 4 specify and the 'new' algorithm suite. (Note that Sections 3 and 4 specify
how the BGPsec_Path attribute can contain signatures, in parallel, how the BGPsec_Path attribute can contain signatures, in parallel,
for two algorithm suites.) Once the transition is complete, use of for two algorithm suites.) Once the transition is complete, use of
the old 'current' algorithm will be deprecated, use of the 'new' the old 'current' algorithm will be deprecated, use of the 'new'
algorithm will be mandatory, and a subsequent 'even newer' algorithm algorithm will be mandatory, and a subsequent 'even newer' algorithm
suite may be specified as recommend to implement. Once the suite may be specified as recommend to implement. Once the
skipping to change at page 32, line 16 skipping to change at page 35, line 16
injecting (unsigned) BGP update messages without injecting (unsigned) BGP update messages without
BGPsec_Path_Signature attributes, injecting BGPsec update messages BGPsec_Path_Signature attributes, injecting BGPsec update messages
with BGPsec_Path_Signature attributes that fail validation, or with BGPsec_Path_Signature attributes that fail validation, or
causing the peer to tear-down the BGP session. The use of BGPsec does causing the peer to tear-down the BGP session. The use of BGPsec does
nothing to increase the power of an on-path adversary -- in nothing to increase the power of an on-path adversary -- in
particular, even an on-path adversary cannot cause a BGPsec speaker particular, even an on-path adversary cannot cause a BGPsec speaker
to believe a BGPsec-invalid route is valid. However, as with any BGP to believe a BGPsec-invalid route is valid. However, as with any BGP
session, BGPsec sessions SHOULD be protected by appropriate transport session, BGPsec sessions SHOULD be protected by appropriate transport
security mechanisms. security mechanisms.
One might be concerned about a potential attack in which an adversary
replays a valid signature on an origin Secure_Path segment as though
it were a signature on later Secure_Path segment (in a different
update message). The only way such an attack could succeed would be
if a structure of bits to be signed in Section 4.1 (origin segment)
could also be parsed as a valid sequence of bits to be signed in
Section 4.2 (later segment). This, in particular, would require that
the length of the two structures match exactly, which cannot happen
given the current choice of algorithms in [10]. We do not expect this
to be a problem with future signature algorithms, as it is likely
that signatures will get longer (instead of shorter) over time.
However, authors of future revisions of the algorithms document [10]
should take care to ensure that this attack remains infeasible.
8. IANA Considerations 8. IANA Considerations
TBD: Need IANA to assign numbers for the two capabilities and the This document registers a new capability in the registry of BGP
BGPsec_PATH attribute. Capabilities. The description for the new capability is "BGPsec
Capability". The reference for the new capability is this document
(i.e., the RFC that replaces draft-ietf-sidr-bgpsec-protocol).
This document registers a new path attribute in the registry of BGP
Path Attributes. The code for this new attribute is "BGPsec_PATH".
The reference for the new capability is this document (i.e., the RFC
that replaces draft-ietf-sidr-bgpsec-protocol).
This document does not create any new IANA registries. This document does not create any new IANA registries.
9. Contributors 9. Contributors
9.1. Authors 9.1. Authors
Rob Austein Rob Austein
Dragon Research Labs Dragon Research Labs
sra@hactrn.net sra@hactrn.net
skipping to change at page 33, line 46 skipping to change at page 36, line 46
Doug Montgomery Doug Montgomery
USA National Institute of Standards and Technology USA National Institute of Standards and Technology
dougm@nist.gov dougm@nist.gov
Kotikalapudi Sriram Kotikalapudi Sriram
USA National Institute of Standards and Technology USA National Institute of Standards and Technology
kotikalapudi.sriram@nist.gov kotikalapudi.sriram@nist.gov
Samuel Weiler Samuel Weiler
Sparta Parsons
weiler+ietf@watson.org weiler+ietf@watson.org
9.2. Acknowledgements 9.2. Acknowledgements
The authors would like to thank Michael Baer, Luke Berndt, Sharon The authors would like to thank Michael Baer, Luke Berndt, Sharon
Goldberg, Ed Kern, Chris Morrow, Doug Maughan, Pradosh Mohapatra, Goldberg, Ed Kern, Chris Morrow, Doug Maughan, Pradosh Mohapatra,
Russ Mundy, Sandy Murphy, Keyur Patel, Mark Reynolds, Heather Russ Mundy, Sandy Murphy, Keyur Patel, Mark Reynolds, Heather
Schiller, Jason Schiller, John Scudder, Ruediger Volk and David Ward Schiller, Jason Schiller, John Scudder, Ruediger Volk and David Ward
for their valuable input and review. for their valuable input and review.
skipping to change at page 34, line 20 skipping to change at page 37, line 20
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[2] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border [2] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border
Gateway Protocol 4", RFC 4271, January 2006. Gateway Protocol 4", RFC 4271, January 2006.
[3] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, [3] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760, January 2007. "Multiprotocol Extensions for BGP-4", RFC 4760, January 2007.
[4] Vohra, Q. and E. Chen, "BGP Support for Four-octet AS Number [4] Vohra, Q. and E. Chen, "BGP Support for Four-octet AS Number
Space", RFC 4893, May 2007. Space", RFC 6793, December 2012.
[5] Traina, P., McPherson, D., and J. Scudder, "Autonomous System [5] Traina, P., McPherson, D., and J. Scudder, "Autonomous System
Confederations for BGP", RFC 5065, August 2007. Confederations for BGP", RFC 5065, August 2007.
[6] Scudder, J. and R. Chandra, "Capabilities Advertisement with [6] Scudder, J. and R. Chandra, "Capabilities Advertisement with
BGP-4", RFC 5492, February 2009. BGP-4", RFC 5492, February 2009.
[7] Lepinski, M. and S. Kent, "An Infrastructure to Support Secure [7] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
Internet Routing", RFC 6480, February 2012.
[8] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
Origin Authorizations (ROAs)", RFC 6482, February 2012. Origin Authorizations (ROAs)", RFC 6482, February 2012.
[9] Patel, K., Ward, D., and R. Bush, "Extended Message support for [8] Patel, K., Ward, D., and R. Bush, "Extended Message support for
BGP", draft-ietf-idr-bgp-extended-messages (work in progress), BGP", draft-ietf-idr-bgp-extended-messages (work in progress),
January 2015. January 2015.
[10] Reynolds, M., Turner, S., and S. Kent, "A Profile for BGPsec [9] Reynolds, M., Turner, S., and S. Kent, "A Profile for BGPsec
Router Certificates, Certificate Revocation Lists, and Router Certificates, Certificate Revocation Lists, and
Certification Requests", draft-ietf-sidr-bgpsec-pki-profiles Certification Requests", draft-ietf-sidr-bgpsec-pki-profiles
(work in progress), November 2014. (work in progress), November 2014.
[11] Turner, S., "BGP Algorithms, Key Formats, & Signature Formats", [10] Turner, S., "BGP Algorithms, Key Formats, & Signature Formats",
draft-ietf-sidr-bgpsec-algs (work in progress), July 2014. draft-ietf-sidr-bgpsec-algs (work in progress), July 2014.
[12] Scudder, J., Chen, E., Mohapatra, P., and K. Patel, "Revised [11] Scudder, J., Chen, E., Mohapatra, P., and K. Patel, "Revised
Error Handling for BGP UPDATE Messages", draft-ietf-idr-error- Error Handling for BGP UPDATE Messages", draft-ietf-idr-error-
handling (work in progress), December 2014. handling (work in progress), December 2014.
11. Informative References 11. Informative References
[12] Lepinski, M. and S. Kent, "An Infrastructure to Support Secure
Internet Routing", RFC 6480, February 2012.
[13] Kumari, W. and K. Sriram, "Recommendation for Not Using AS_SET [13] Kumari, W. and K. Sriram, "Recommendation for Not Using AS_SET
and AS_CONFED_SET in BGP", RFC 6472, December 2011. and AS_CONFED_SET in BGP", RFC 6472, December 2011.
[14] Kent, S. and A. Chi, "Threat Model for BGP Path Security", RFC [14] Kent, S. and A. Chi, "Threat Model for BGP Path Security", RFC
7132, February 2014. 7132, February 2014.
[15] Bush, R. and R. Austein, "The Resource Public Key [15] Bush, R. and R. Austein, "The Resource Public Key
Infrastructure (RPKI) to Router Protocol", RFC 6810, January Infrastructure (RPKI) to Router Protocol", RFC 6810, January
2013. 2013.
 End of changes. 48 change blocks. 
99 lines changed or deleted 137 lines changed or added

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