saag G. Lebovitz Internet-Draft Juniper Intended status: Informational March 10, 2009 Expires: September 11, 2009 Roadmap for Cryptographic Authentication of Routing Protocol Packets on the Wire draft-lebovitz-kmart-roadmap-01 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on September 11, 2009. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Abstract In the March of 2006 the IAB held a workshop on the topic of "Unwanted Internet Traffic". The report from that workshop is Lebovitz & Expires September 11, 2009 [Page 1] Internet-Draft KMART Roadmap March 2009 documented in RFC 4948 [RFC4948]. Section 8.2 of RFC 4948 calls for "[t]ightening the security of the core routing infrastructure." Four main steps were identified for improving the security of the routing infrastructure. One of those steps was "securing the routing protocols' packets on the wire." One mechanism for securing routing protocol packets on the wire is the use of per-packet cryptographic message authentication, providing both peer authentication and message integrity. Many different routing protocols exist and they employ a range of different transport subsystems. Therefore there must necessarily be various methods defined for applying cryptographic authentication to these varying protocols. Many routing protocols already have some method for accomplishing cryptographic message authentication. However, in many cases the existing methods are dated, vulnerable to attack, and/or employ cryptographic algorithms that have been deprecated. This document creates a roadmap of protocol specification work for the use of modern cryptogrpahic mechanisms and algorithms for message authentication in routing protocols. It also defines the framework for a key management protocol that may be used to create and manage session keys for message authentication and integrity. This roadmap reflects the input of both the security area and routing area in order to form a jointly agreed upon and prioritized work list for the effort. Lebovitz & Expires September 11, 2009 [Page 2] Internet-Draft KMART Roadmap March 2009 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.2. Requirements Language . . . . . . . . . . . . . . . . . . 4 1.3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.4. Goals . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.5. Non-Goals . . . . . . . . . . . . . . . . . . . . . . . . 9 1.6. Audience . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. Threats . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2.1. Threats In Scope . . . . . . . . . . . . . . . . . . . . . 10 2.2. Threats Out of Scope . . . . . . . . . . . . . . . . . . . 12 3. Categorizing Routing Protocols . . . . . . . . . . . . . . . . 13 3.1. Category: Messaging Transaction Type . . . . . . . . . . . 13 3.2. Category: Peer vs. Group Keying . . . . . . . . . . . . . 14 3.3. Security Characterization Vectors . . . . . . . . . . . . 14 3.3.1. Internal vs. External Operation . . . . . . . . . . . 15 3.3.2. Unique versus Shared Keys . . . . . . . . . . . . . . 15 3.3.3. Out-of-Band vs. In-line Key Management . . . . . . . . 17 4. The Roadmap . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.1. Work Phases on any Particular Protocol . . . . . . . . . . 18 4.2. Requirements for Phase 1 BaseRPs' Security Update . . . . 20 4.3. Common Framework . . . . . . . . . . . . . . . . . . . . . 21 4.4. Work Items Per Routing Protocol . . . . . . . . . . . . . 26 4.5. Protocols in Categories . . . . . . . . . . . . . . . . . 27 4.6. Priorites . . . . . . . . . . . . . . . . . . . . . . . . 29 5. Security Considerations . . . . . . . . . . . . . . . . . . . 29 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 30 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 30 8. Change History (RFC Editor: Delete Before Publishing) . . . . 30 9. Needs Work in Next Draft (RFC Editor: Delete Before Publishing) . . . . . . . . . . . . . . . . . . . . . . . . . 32 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 32 10.1. Normative References . . . . . . . . . . . . . . . . . . . 32 10.2. Informative References . . . . . . . . . . . . . . . . . . 32 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 34 Lebovitz & Expires September 11, 2009 [Page 3] Internet-Draft KMART Roadmap March 2009 1. Introduction In March 2006 the Internet Architecture Board (IAB) held a workshop on the topic of "Unwanted Internet Traffic". The report from that workshop is documented in RFC 4948 [RFC4948]. Section 8.1 of that document states that "A simple risk analysis would suggest that an ideal attack target of minimal cost but maximal disruption is the core routing infrastructure." Section 8.2 calls for "[t]ightening the security of the core routing infrastructure." Four main steps were identified for that tightening: o More secure mechanisms and practices for operating routers. This work is being addressed in the OpSec Working Group. o Cleaning up the Internet Routing Registry repository [IRR], and securing both the database and the access, so that it can be used for routing verifications. This work is being conducted through liaisons with the RIR's globally. o Specifications for cryptographic validation of routing message content. This work is being done in the SIDR Working Group. o Securing the routing protocols' packets on the wire This document addresses the last bullet, securing the packets on the wire of the routing protocol exchanges. 1.1. Terminology [to be filled out later] Base RP key_store KMP session keys 1.2. Requirements Language 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 RFC 2119 [RFC2119]. 1.3. Scope Four basic tactics may be employed in order to secure any piece of data as it is transmitted over the wire: privacy (or encryption), authentication, message integrity, and non-repudiation. The focus for this effort, and the scope for this roadmap document, will be Lebovitz & Expires September 11, 2009 [Page 4] Internet-Draft KMART Roadmap March 2009 message authentication and packet integrity only. This work explicitly excludes, at this point in time, the other two tactics: privacy and non-repudiation. Since the objective of most routing protocols is to broadly advertise the routing topology, routing messages are commonly sent in the clear; confidentiality is not normally required for routing protocols. However, ensuring that routing peers truly are the trusted peers expected, and that no roque peers or messages can compromise the stability of the routing environment is critical, and thus our focus. The other two explicitly excluded tactics, privacy and non-repudiation, may be addressed in future work. It is possible for routing protocol packets to be transmitted employing all four security tactics mentioned above using existing standards. For example, one could run unicast, layer 3 or above routing protocol packets through IPsec ESP [RFC4303]. This would provide the added benefit of privacy, and non-repudiation. However, routing products have been fine tuned over the years for the specific processing necessary for these routing protocols non-encapsulated formats. Operators are, therefore, quite unwilling to explore new packet encapsulations for these tried and true protocols. In addition, at least in the case of BGP and LDP, these protocols already have existing mechanisms for cryptographically authenticating and integrity checking the packets on the wire. Products with these mechanisms have already been produced, code has already been written and both have been optimized for the existing mechanisms. Rather than turn away from these mechanisms, we want to enhance them, updating them to modern and secure levels. There are two main work phases for this roadmap, and for any BaseRP work undertaken as part of this roadmap (discussed further in the Work Phases (Section 4.1) section). The first is to enhance the Base RP's current authentication mechanism, ensuring it employs modern cryptographic algorithms and methods for its basic operational model, fulfillling the requirements defined in the Requirements (Section 4.2) section, and protecting against as many of the threats as possible as defined in the Threats (Section 2.1)section. Many of the BaseRPs' current mechanisms use manual keys, so the first phase updates will focus on shoring up the manual key mechanisms that exist. The second work phase is to define the use of a key management protocol (KMP) for creating and managing session keys used in the BaseRPs' message authentication and data integrity functions. It is hoped that a general KMP framework -- or a small number of frameworks -- can be defined and leveraged for many BaseRPs. Lebovitz & Expires September 11, 2009 [Page 5] Internet-Draft KMART Roadmap March 2009 Therefore, the scope of this roadmap of work includes: o Making use of existing routing protocol security protocols, where they exist, and enhancing or updating them as necessary for modern cryptographic best practices, o Developing a framework for using automatic key management in order to ease deployment, lower cost of operation, and allow for rapid responses to security breaches, and o Specifying the automated key management protocol that may be combined with the bits-on-the-wire mechanisms. The work also serves as an agreement between the Routing Area and the Security Area about the priorities and work plan for incrementally delivering the above work. This point is important. There will be times when the best-security-possible will give way to vastly- improved-over-current-security-but-admittedly-not-yet-best-security- possible, in order that incremental progress toward a more secure Internet may be achieved. As such, this document will call out places where agreement has been reached on such trade offs. This document does not contain protocol specifications. Instead, it defines the areas where protocol specification work is needed and sets a direction, a set of requirements, and a relative priority for addressing that specification work. There are a set of threats to routing protocols that are considered in-scope for this document/roadmap, and a set considered out-of- scope. These are described in detail in the Threats (Section 2) section below. 1.4. Goals The goals and general guidance for this work roadmap follow: 1. Provide authentication and integrity protection for packets on the wire of existing routing protocols 2. Deliver a path to incrementally improve security of the routing infrastructure. The principle of crawl, walk, run will be in place. Routing protocol authentication mechanisms may not go immediately from their current state to a state containing the best possible, most modern security practices. Incremental steps will need to be taken for a few very practical reasons. First, there is a great deal of deployed routing devices in operating networks that will not be able to run the most modern cryptographic mechanisms without significant and unacceptable Lebovitz & Expires September 11, 2009 [Page 6] Internet-Draft KMART Roadmap March 2009 performance penalties. The roadmap for any one routing protocol MUST allow for incremental improvements on existing operational devices. Second, current routing protocol performance on deployed devices has been achieved over the last 20 years through extensive tuning of software and hardware elements, and is a constant focus for improvement by vendors and operators alike. The introduction of new security mechanisms affects this performance balance. The performance impact of any incremental step of security improvement will need to be weighed by the community, and introduced in such a way that allows the vendor and operator community a path to adoption that upholds reasonable performance metrics. Therefore, certain specification elements may be introduced carrying the "SHOULD" guidance, with the intention that the same mechanism will carry a "MUST" in the next release of the specification. This gives the vendors and implementors the guidance they need to tune their software and hardware appropriately over time. Last, some security mechanisms require the build out of other operational support systems, and this will take time. An example where these three reasons are at play in an incremental improvement roadmap is seen in the improvement of BGP's [RFC4271] security via the update of the TCP Authentication Option (TCP-AO) [I-D.ietf-tcpm-tcp-auth-opt] effort. It would be ideal, and reflect best common security practice, to have a fully specified key management protocol for negotiating TCP-AO's authentication material, using certificates for peer authentication in the keying. However, in the spirit of incremental deployment, we will first address issues like cryptographic algorithm agility, replay attacks, TCP session resetting in the base TCP-AO protocol before we layer key management on top of it. 3. The deploy-ability of the improved security solutions on currently running routing infrastructure equipment. This begs the consideration of the current state of processing power available on routers in the network today. 4. Operational deploy-ability - A solutions acceptability will also be measured by how deployable the solution is by common operator teams using common deployment processes and infrastructures. I.e. We will try to make these solutions fit as well as possible into current operational practices or router deployment. This will be heavily influenced by operator input, to ensure that what we specify can -- and, more importantly, will -- be deployed once specified and implemented by vendors. Deployment of incrementally more secure routing infrastructure in the Internet is the final measure of success. Lebovitz & Expires September 11, 2009 [Page 7] Internet-Draft KMART Roadmap March 2009 Interviews with operators show several points about routing security. First, only about 25% of operators have deployed security in their routing protocols [REF???, Danny, you got one?]. Of those who have deployed, only about [25% ??] of their routers are deployed with the authentication enabled. Most report deploying with one single manual key throughout the entire network. These same operators report that the one single key has not been changed since it was originally installed, sometimes five or more years ago. When asked why, particularly for the case of BGP using TCP MD5, the following reasons are often given: A. Changing the keys brings down the links/adjacencies, undermining Service Level Agreements (SLAs). B. For external peers, difficulty of coordination with the other organization. They often don't know who the contact is at the other organization, so they don't know where to start, and doing so takes a lot of time in research. C. Keys must be changed at precisely the same time in order to limit connectivity outage duration. This is incredibly difficult to do, operationally, especially between different organizations. D. Relatively low priority compared to other operatoinal issues. E. Lack of staff to implement the changes device by device. F. One operator reported that the same key is used for all customer premise equipment. The same operator reported that if the customer mandated, a unique key could be created, although the last time this occurred it created such an operational headache that the administrators now usually tell customers that the option doesn't even exist, to avoid the difficulties. These customer-uniqe keys are never changed, unless the customer demands so. The main threat at play here is that a terminated employee from such an operator who had access to the one (or few) keys used for authentication in these environments could easily wage an attack -- or offer the keys to others who would wage the attack -- and bring down many of the adjacencies, causing destabilization to the routing system. Whatever mechanisms we specify need to be easier than the current methods to deploy, and should provide obvious operational efficiency gains along with significantly better security and threat protection. This combination of value may be enough to drive much broader adoption. Lebovitz & Expires September 11, 2009 [Page 8] Internet-Draft KMART Roadmap March 2009 5. Address the threats enumerated above in the "Threats" section (Section 2) for each routing protocol, along a roadmap. Not all threats may be able to be addressed in the first specification update for any one protocol. Roadmaps will be defined so that both the security area and the routing area agree on how the threats will be addressed completely over time. 6. Reuse common mechanisms across routing protocols whenever possible - For example, designers should aim to re-use the key management protocol that will be defined for BGP's TCP-AO key establishment for as many other routing protocols as possible. This is but one example. 7. Bridge any gaps between routing and security engineers by recording agreements on work items, roadmaps, and guidance from the Area leads and Internet Architecture Board (IAB, www.iab.org). 8. Create a re-usable architecture and guidelines for various IETF working teams who will address these security improvements for various protocols 1.5. Non-Goals The following two goals are considered out-of-scope for this effort: o Privacy of the packets on the wire, at this point in time. Once this roadmap is realized, we may revisit work on privacy. o Message content security. This work is being deal with in other areas, like SIDR. 1.6. Audience The audience for this roadmap includes: o Routing Area working group chairs and members - These people are charged with updates to the routing protocol specifications. Any and all cryptographic authentication work on these specifications will occur in Routing Area working groups. o Security Area reviewers of routing area documents - These people are delegated by the Security Area Directors to perform reviews on routing protocol specifications as they pass through working group last call or IESG review. They will pay particular attention to the use of cryptographic authentication and corresponding security mechanisms for the routing protocols. They will ensure that incremental security improvements are Lebovitz & Expires September 11, 2009 [Page 9] Internet-Draft KMART Roadmap March 2009 being made, in line with this roadmap. o Security Area engineers - These people partner with routing area authors/designers on the security mechanisms in routing protocol specifications. Some of these security area engineers will be assigned by the Security Area Directors, while others will be interested parties. o Operators - The operators are a key audience for this work, as the work is considered to have succeeded if the operators deploy the technology, presumably due to a perception of significantly improved security value coupled with relative similarity to deployment complexity and cost. Conversely, the work will be considered a failure if the operators do not care to deploy it, either due to lack of value or perceived (or real) over- complexity of operations. 2. Threats In RFC4949[RFC4949], a threat is defined as a potential for violation of security, which exists when there is a circumstance, capability, action, or event that could breach security and cause harm. This section defines the threats that are in scope for this roadmap, and those that are explicitly out of scope. This document leverages the "Generic Threats to Routing Protocols" model, RFC 4593 [RFC4593] , capitalizes terms from that document, and offers a terse definition of those terms. (More thorough description of routing protocol threats sources, motivations, consequences and actions can be found in RFC 4593 [RFC4593] itself). The threat listings below expand upon these threat definitions. 2.1. Threats In Scope The threats that will be addressed in this roadmap are those from OUTSIDERS, attackers that may reside anywhere in the Internet, have the ability to send IP traffic to the router, may be able to observe the router's replies, and may even control the path for a legitimate peer's traffic. These are not legitimate participants in the routing protocol. Message authentication and integrity protection specifically aims to identify messages originating from OUTSIDERS. The concept of OUTSIDERS can be further refined to include attackers who are terminated employees, and those sitting on-path. Lebovitz & Expires September 11, 2009 [Page 10] Internet-Draft KMART Roadmap March 2009 o On-Path - attackers with control of a network resource or a tap along the path of packets between two routers. An on-path outsider can attempt a man-in-the-middle attack, in addition to several other attack actions. A man-in-the-middle (MitM) attack occurs when an attacker who has access to packets flowing between two peers tampers with those packets in such a way that both peers think they are talking to each other directly, when in fact they are actually talking to the attacker only. Protocols conforming to this roadmap will use cryptographic mechanisms to prevent a man-in-the-middle attacker from situating himself undetected. o Terminated Employees - in this context, those who had access router configuration that included keys or keying material like pre-shared keys used in securing the routing protocol. Using this material, the attacker could attempt to impersonate a legitimate router. The goal of addressing this source specifically is to call out the case where new keys or keying material becomes necessary very quickly, with little operational expense, upon the termination of such an employee. This grouping could also refer to any attacker who somehow managed to gain access to keying material, and said access had been detected by the operators such that the operators have an opportunity to move to new keys in order to prevent attack. These ATTACK ACTIONS are in scope for this roadmap: o SPOOFING - when an illegitimate device assumes the identity of a legitimate one. Spoofing can be used, for example, to inject unrealistic routing information that causes the disruption of network services. Spoofing can also be used to cause a neighbor relationship to form that subsequently denies the formation of the relationship with the legitimate router. o FALSIFICATION - an action whereby an attacker sends false routing information. To falsify the routing information, an attacker has to be either the originator or a forwarder of the routing information. Falsification may occur by an ORIGINATOR, or a FORWARDER, and may involve OVERCLAIMING, MISCLAIMING, or MISTATEMENT of network resource reachability. We must be careful to remember that in this work we are only targeting falsification from outsiders as may occur from tampering with packets in flight. Falsification from BYZANTINES (see the Threats Out of Scope section (Section 2.2) below) are not addressed by this roadmap, but by other work in the IETF. Lebovitz & Expires September 11, 2009 [Page 11] Internet-Draft KMART Roadmap March 2009 o INTERFERENCE - when an attacker inhibits the exchanges by legitimate routers. The types of interference addressed by this work include: * ADDING NOISE * REPLAYING OUT-DATED PACKETS * INSERTING MESSAGES * CORRUPTING MESSAGES * BREAKING SYNCHRONIZATION * Changing message content o DoS attacks on transport sub-systems - This includes any other DoS attacks specifically based on the above attack types. This is when an attacker sends packets aimed at halting or preventing the underlying protocol over which the routing protocol runs, for example halting a BGP session by sending a TCP FIN packet. Another example is sending packets which confuse or overwhelm a security mechanism itself, for example initiating an overwhelming load of keying protocol initiations from bogus sources. All other possible DoS attacks are out of scope (see next section). 2.2. Threats Out of Scope Threats from BYZANTINE sources -- faulty, misconfigured, or subverted routers, i.e., legitimate participants in the routing protocol -- are out of scope for this roadmap. Any of the attacks described in the above section (Section 2.1) that may be levied by a BYZANTINE source are therefore also out of scope. In addition, these other attack actions are out of scope for this work: o SNIFFING - passive observation of route message contents in flight o FALSIFICATION by BYZANTINE sources - unauthorized message content by a legitimate source. o INTERFERENCE due to: * NOT FORWARDING PACKETS - cannot be prevented with cryptographic authentication * DELAYING MESSAGES - cannot be prevented with cryptographic authentication * DENIAL OF RECEIPT - cannot be prevented with cryptographic authentication * UNAUTHORIZED MESSAGE CONTENT - the work of the IETF's SIDR working group grouphttp://www.ietf.org/html.charters/sidr-charter.html). * Any other type of DoS attack. For example, a flood of traffic that fills the link ahead of the router, so that the router is rendered unusable and unreachable by valid packets is NOT an Lebovitz & Expires September 11, 2009 [Page 12] Internet-Draft KMART Roadmap March 2009 attack that this work will address. Many other such examples could be contrived. 3. Categorizing Routing Protocols For the purpose of this security roadmap definition, we will categorize the routing protocols into groups and have design teams focus on the specification work within those groupings. It is believed that the groupings will have like requirements for their authentication mechanisms, and that reuse of authentication mechanisms will be greatest within these grouping. The work items placed on the roadmap will be defined and assigned based on these categorizations. It is also hoped that, down the road in the Phase 2 work, we can create one KMP per category (if not for several categories) so that the work can be easily leveraged by the various RP teams. KMPs are useful for allowing simple, automated updates of the traffic keys used in a base protocol. KMPs replace the need for humans, or OSS routines, to periodically replace keys on running systems. It also removes the need for a chain of manual keys to be chosen or configured. When configured properly, a KMP will enforce the key freshness policy of two peers by keeping track of the key lifetime and negotiating a new key at the defined interval. 3.1. Category: Messaging Transaction Type The first categorization defines four types of messaging transactions used on the wire by the base routing protocol, the Base RP. They are: One-to-One One peer router directly and intentionally delivers a route update specifically to one other peer router. Examples are BGP and LDP. [question to reviewers: Should we list all protocols into these categories right here, or just give a few examples?] One-to-Many A router peers with multiple other routers on a single network segment -- i.e. on link local -- such that it creates and sends one route update message which is intended for consumption by multiple peers. Examples would be OSPF and IS-IS. Client-Server A client-server routing protocol is one where one router initiates a request for route information from another router, who then formulates a response to that request, and replies with the requested data. Examples are a BGP Route Reflector and [???? Are Lebovitz & Expires September 11, 2009 [Page 13] Internet-Draft KMART Roadmap March 2009 there other examples? Is this the right example?]. Multicast Multicast protocols have unique security properties because of the fact that they are inherently group- based protocols and thus have group keying requirements at the routing level where link-local routing messages are multicasted. Also, at least in the case of PIM-SM, some messages are are sent unicast to a given peer(s), as is the case with router-close- to-sender and the "Rendezvous Point". Some work for application layer message security has been done in the Multicast Security working group (MSEC, http://www.ietf.org/html.charters/msec-charter.html) and may be helpful to review, but is not directly applicable. [author's note: I think the above definitions need clean up. Routing area folks, especially ADs, PLEASE suggest new text.] 3.2. Category: Peer vs. Group Keying The second axis of categorization groups protocols by the keying mechanism that will be necessary for distributing session keys to the actual routing protocol transports. They are: Peer keying One router sends the keying messages directly and only to one other router, such that a one-to-one, unique keying security association (SA) is established between the two routers Group Keying One router creates and distributes a single keying message to multiple peers. In this case an group SA will be established and used between multiple peers simultaneously. Group keying exists for protocols like OSPF [RFC2328] , and also for multicast protocols like PIM-SM [RFC4601]. 3.3. Security Characterization Vectors A few more considerations must be made about the protocol and its use when initially categorizing the protocol and scoping the authentication work. Lebovitz & Expires September 11, 2009 [Page 14] Internet-Draft KMART Roadmap March 2009 3.3.1. Internal vs. External Operation The designers must consider whether the protocol is an internal routing protocol or an external one, i.e. Does it primarily run between peers within a single domain of control or between two different domains of control? Some protocols may be used in both cases, internally and externally, and as such various modes of authentication operation may be required for the same protocol. While it is preferred that all routing exchanges run with the utmost security mechanisms enabled in all deployments, the exhortation is greater for those protocols running at a peering point between two domains of control, and greatest for those on public exchange point links, because the volume of attackers are greater from the outside. Note however that the consequences of internal attacks maybe no less severe -- in fact they may be quite a bit more sever -- than an external attack. An example of this internal versus external consideration is BGP which has both EBGP and IBGP modes. Another example is a multicast protocol where the neighbors are sometimes within a domain of control and sometimes external, like at an exchange link. It would be more acceptable to give up some security to get some convenience by using a group key on large broadcast networks within your domain, whereas operators may favor security over convenience and use unique keying on peering links. In this case again, designers must consider both modes of operation and ensure the authentication mechanisms fit both. Operators are encouraged to run cryptographic authentication on all their adjacencies, but to work from the outside in, i.e. The EBGP links are a higher priority than the IBGP links because they are externally facing. 3.3.2. Unique versus Shared Keys This section discusses security considerations of when it is appropriate to use the same authentication key inputs for multiple peers and when it is not. This is largely a debate of convenience versus security. It is often the case that the best secured mechanism is also the least convenient mechanism. For example, an air gap between a host and the network absolutely prevents remote attacks on the host, but having to copy and carry files using the "sneaker net" is quite inconvenient and unscalable. Operators have erred on the side of convenience when it comes to securing routing protocols with cryptographic authentication. Many do not use it at all. Some use it only on external links, but not on internal links. Those that do use it often use the same key for all peers across their entire network. It is common to see the same key in use for years, and that being the same key that was entered when Lebovitz & Expires September 11, 2009 [Page 15] Internet-Draft KMART Roadmap March 2009 authentication was originally configured. The goal for designers is to create authentication mechanisms that are easy for the operators to deploy, and still use unique keys. Operators have the impression that they NEED shared keys, when in fact they do not. What they need is the relative convenience they experience from deploying cryptographic authentication with shared keys, compared to the inconvenience they would experience if they deployed the same authentication mechanism using unique keys per pair. An example is BGP Route Reflectors. Here operators often use the same authentication key between each client and the route reflector. The roadmaps defined from this guidance document will allow for unique keys to be used between each client and the peer, without sacrificing much convenience. Designers should strive to deliver unique keying mechanisms with similar ease-of-deployment properties as today's shared keys. Operators must understand the consequences of using shared keys across many peers. Unique keys are more secure than shared keys because the reduce both the attack target size and the attack consequence size. In this context, the attack target size represents the number of unique routing exchanges across a network that an attacker may be able to observe in order to gain security association credentials, i.e. Crack the keys. If a shared key is used across the entire internal domain of control, then the attack target size is very large. The larger the attack target, the easier it is for the attacker to gain access to analysis data, and greater the volume of analysis data he can access, both of which make his job easier. In this context, the attack consequence size represents the amount of routing adjacencies that can be negatively affected once a breach has occurred, i.e. Once the keys have been acquired by the attacker. Again, if a shared key is used across the internal domain, then the consequence size is the whole network. Ideally, unique key pairs would be used for each adjacency. In some cases designers may need to use shared keys in order to solve the given problem space. For example, a multicast packet is sent once but then observed and consumed by several routing neighbors. If unique keys were used per neighbor, the benefit of multicast would be erased because the casting peer would have to create a different announcement packet/stream for each listening peer. Though this may be desired and acceptable in some small amount of use cases, it is not the norm. Shared group keys are an acceptable solution here, and much work has been done already in this area (see MSEC working group). Lebovitz & Expires September 11, 2009 [Page 16] Internet-Draft KMART Roadmap March 2009 3.3.3. Out-of-Band vs. In-line Key Management This section discusses the security and use case considerations for keys placed on devices through out-of-band configurations versus through one routing peer-to-peer key management protocol exchanges. Note, when we say here "Peer-to-Peer KMP" we do not mean in-band to the RP. Instead, we mean that the exchange occurs in-line, over IP, between the two routing peers directly. In in-line KMP the peers themselves handle the key and security association negotiation between themselves directly, whereas in an out-of-band system the keys are placed onto the device through some other configuration or management method or interface. An example of an out-of-band mechanism could be an administrator who makes a remote management connection (e.g. using SSH) to a router and manually enters the keying information -- like the algorithm, the key(s), the lifetimes, etc. Another example could be an OSS system which inputs the same information via a script over an SSH connection, or by pushing configuration through some other management connection, standard (Netconf-based) or proprietary. The drawbacks of an out-of-band mechanism include: lack of scale- ability, complexity and speed of changing if breech is suspected. For example, if an employee who had access to keys was was terminated, or if a machine holding those keys was belived compromised, then the system would be considered insecure and vulnerable until new keys were defined by a human. Those keys then need to be placed into the OSS system, manually, and the OSS system then needs to push the change -- often during a very limited change window -- into the relevant devices. If there are multiple organizations involved in these connections, this process is greatly complicated. The benefits of out-of-band mechanism is that once the new keys/ parameters are set in OSS system they can be pushed automatically to all devices within the OSS's domain of control. Operators have mechanisms in place for this already. In small environments with few routers, a manual system is not difficult to employ. We further define an in-line key exchange as using cryptographicly protected identity verification, session key negotiation, and security association parameter negotiation between the two routing peers. The KMP between the two peers may also include the negotiation of parameters, like algorithms, cryptographic inputs (e.g. initialization vectors), key life-times, etc. The benefits an in-line KMP are several. An in-line KMP results in key(s) that are privately generated, and not recorded permanently Lebovitz & Expires September 11, 2009 [Page 17] Internet-Draft KMART Roadmap March 2009 anywhere. Since the traffic keys used in a particular connection are not a fixed part of a device configuration no steal-able data exists anywhere else in the operator's systems which can be stolen, e.g. in the case of a terminated or turned employee. If a server or other data store is stolen or compromised, the thieves gain no access to current traffic keys. They may gain access to key derivation material, like a PSK, but not current traffic keys in use. In this example, these PSKs can be updated into the device configurations (either manually or through an OSS) without bouncing or impacting the existing session at all. In the case of using raw assymetric keys or certificates, instead of PSKs, the data theft would likely not even result in any compromise, as the key pairs would have been generated on the routers, and never leave those routers. In such a case no changes are needed on the routers; the connections will continue to be secure, non-compromised. Additoinally, with a KMP regular re-keys operations occur without any operator involvement or oversight. This keeps keys fresh. The drawbacks to using a KMP are few. First, a KMP requires more cryptographic processing for the router at the very beginning of a connection. This will add some minor start-up time to connection establishment versus a purely manual key approach. Once a connection with traffic keys have been established via a KMP, the performance is the same in the KMP and the out-of-band case. KMPs also add another layer of protocol and configuration complexity which can fail or be misconfigured. This was more of an issue when these KMPs were first deployed, but less so as these implementaitons and operational experience with them has matured. The desired end goal is in-line KMPs. 4. The Roadmap 4.1. Work Phases on any Particular Protocol The desired endstate for the KMART work contains several items. First, the people desiring to deploy securely authenticated and integrity validated packets between routing peers have the tools specified, implemented and shipping in order to deploy. These tools should be fairly simple to implement, and not more complex than the security mechanisms to which the operators are already accustomed. (Examples of security mechanisms to which router operators are accustomed include: the use of assymetric keys for authentication in SSH for router configuration, the use of pre-shared keys (PSKs) in TCP MD5 for BGP protection, the use of self-signed certificates for HTTPS access to device Web-based user interfaces, the use of strongly constructed passwords and/or identity tokens for user identification Lebovitz & Expires September 11, 2009 [Page 18] Internet-Draft KMART Roadmap March 2009 when logging into routers and management systems.) While the tools that we intend to specify may not be able to stop a deployment from using "foobar" as an input key for every device across their entire routing domain, we intend to make a solid, modern security system that is not too much more difficult than that. In other words, simplicity and deployability are keys to success. The Base RP's will specify modern cryptographic algorithms and security mechanisms. Routing peers will be able to employ unique, pair-wise keys per peering instance, with reasonable key lifetimes, and updating those keys on a somewhat regular basis will be operationally easy, causing no service interruption. The reach the above described end-state using manual keys may only be pragmatic in very small deployments. In larger deployments, this end state will be much more operationally difficult to reach with only manual keys. Thus, there will be a need for key lifecycle management, in the form of a key management protocol, or KMP. We expect that the two forms, manual key usage and KMP usage, will co- exist in the real world. For example, a provider's edge router at a public exchange peering point will want to use a KMP for ensuring unique and fresh keys with external peers, while a manual key may be used between a provider's access edge router and each of the same provider's customer premise routers with which it peers. In accordance with the desired end state just described, we define two main work phases for each Base RP: 1. Enhance the Base RP's current authentication mechanism. This work involves enhancing a Base RP's current security mechanisms in order to achieve a consistent, modern level of security functionality within its existing keying framework. It is understood and accepted that the existing keying frameworks are largely based on manual keys. Since many operators have already built operational support systems (OSS) around these manual key implementations, there is some automation available for an operator to leverage in that way, if the underlying mechanisms are themselves secure. In this phase, we explicitly exclude embedding or creating a KMP. A list of the requirements for Phase 1 work are below in the section "Requirements for Phase 1 BaseRPs' Security Updates (Section 4.2). 2. Develop an automated keying framework. The second phase will focus on the development of an automated keying framework to faciliate unique pair-wise (or perhaps group-wise, where applicable) keys per peering isntance. This involves the use of a KMP. A KMP is helpful because [will add a more full description here, sorry, ran out of time]. The framework for any one BaseRP will fall under, and be able to leverage, the generic Lebovitz & Expires September 11, 2009 [Page 19] Internet-Draft KMART Roadmap March 2009 framework described below in section Section 4.3. 4.2. Requirements for Phase 1 BaseRPs' Security Update Here is a proposed list of requirements that SHOULD be addressed by Phase 1 (according to "1." above) security updates to Base RPs [to be reviewed after -01 is released]: 1. Clear definitions of which elements of the transmission (frame, packet, segment, etc.) are protected by the authentication mechanism 2. Strong algorithms, and defined and accepted by the security community, MUST be specified. The option should use algorithms considered accepted by the security community, which are considered appropriately safe. The use of non-standard or unpublished algorithms SHOULD BE avoided. 3. Algorithm agility for the cryptograhpic algorithms used in the authentication MUST be specified, i.e. more than one algorithm MUST be specified and it is clear how new algorithms MAY be specified and used. 4. Secure use of simple PSKs, offering both operational convenience as well as building something of a fence around stupidity, MUST be specified. 5. Inter-connection replay protection. Packets captured from one connection MUST NOT be able to be re-sent and accepted during a later connection. 6. Intra-connection replay protection. Packets captured during a connection MUST NOT be able to be re-sent and accepted during that same connection, to deal with long-lived connections. 7. A change of security parameters REQUIRES, and even forces, a change of session traffic keys 8. Intra-connection re-keying which occurs without a break or interruption to the current peering session, and, if possible, without data loss, MUST be specified. 9. Efficient re-keying SHOULD be provided. The specificaion SHOULD support rekeying during a connection without the need to expend undue computational resources. In particular, the specification SHOULD avoid the need to try/compute multiple keys on a given packet. 10. Prevent DoS attacks as those described as in-scope in the threats section Section 2.1above 11. Default mechanisms and algorithms specified and defined as REQUIRED for all implementations 12. Manual keying MUST be supported. 13. Architecture of the specification MUST consider and allows for future use of a KMP. Lebovitz & Expires September 11, 2009 [Page 20] Internet-Draft KMART Roadmap March 2009 4.3. Common Framework Each of the categories of routing protocols above will require unique designs for authenticating and integrity checking their protocols. However, a single underlying framework for delivering automatic keying to those solutions will be pursued. Providing such a single framework will significantly reduce the complexity of each step of the overall roadmap. For example, if each Base RP needed to define it's own key management protocol this would balloon the total amount of different sockets that needed to be opened and processes that needed to be simultaneously running on an implementation. It would also significantly increase the run-time complexity and memory requirements of such systems running multiple Base RPs, causing perhaps slower performance of such systems. However, if we can land on a very small set (perhaps one or two) of automatic key management protocols, KMPs, that the various Base RP's can use, then we can reduce this implementation and run-time complexity. We can also decrease the total amount of time implementers need to deliver the KMPs for the Base RPs that will provide better threat protection. The components for the framework are listed here, and described below: o BaseRP security mechanism o KMP o KeyStore o BaseRP-to-KMP API o BaseRP-to-KeyStore API o KMP-to-KeyStore API o Common Base RP mechanisms o Identifiers o Proof of identity o Profiles The framework is modularized for how keys and security association (SA) parameters generally get passed from a KMP to a transport protocol. It contains three main blocks and APIs. Lebovitz & Expires September 11, 2009 [Page 21] Internet-Draft KMART Roadmap March 2009 +------------+ +--------------------+ | | | | Check +-----------+ | Identifier +-->| +---------->| | | | | KMP Function | | Identity | +----------- + | |<----------+ Proof | | | Approve | | +-+--------------+---+ +-----------+ | | KMP-to-KeyStore | | API | | \|/ | +-------+-------+ | | | | KMP-to-BaseRP | Session | | API | KeyStore | | | | | +-------+-------+ | | | | | KeyStore-to- | | BaseRP API | | | \|/ +--------------------------+-------------+ | | | | \|/ Common BaseRP | | +-------+-------+ Authentication | | | | Mechanisms | +---| Transport |-----+--------------+ | | Key(s) | | | | | | | +---------------+ Specific BaseRP | | Authentication | | Security | | Mechanism | | | +----------------------------------------+ Figure 1: Automatic Key Management Framework Each element of the framework is described here: o Base RP - Base RP security mechanism - In each case, the Base RP will contain a mechanism for using session keys in their security option. Lebovitz & Expires September 11, 2009 [Page 22] Internet-Draft KMART Roadmap March 2009 o KeyStore - Each implementation will also contain a protocol independent mechanism for storing keys, called KeyStore. The key_store will have multiple different logical containers, one container for each session key that any given Base RP will need. o RP-KeyStore API - There will be an API for Base RP to retrieve the keys from the KeyStore. This will enable implementers to reuse the same API calls for all their Base RPs. The API will necessarily include facility to retrieve other parameters required for the construction of the BaseRP's packets, like key IDs or key lifetimes, etc. o KMP - There will be an automated key management protocol, KMP. This KMP will run between the peers. The KMP serves as a protected channel between the peers, through which they can negotiate and pass important data required to exchange proof of key identifiers, derive session keys, determine re-keying, synchronize their keying state, signal various keying events, notify with error messages, etc. As an analogy, in the IPsec protocol (RFC4301 [RFC4301], RFC4303 [RFC4303] and RFC4306 [RFC4306]) IKEv2 is the KMP that runs between the two peers, while AH and ESP are two different base protocols that take session keys from IKEv2 and use them in their transmissions. In the analogy, the Base RP, say BGP and LDP, are analogous to ESP and AH, while the KMP is analogous to IKEv2 itself. o RP-KMP API - There will be an API for the Base RP to request a session key of the KMP, and be notified when the keys are available for it. The API will also contain a mechanism for the KMP to notify the Base RP that there are new keys that it must now use, even if it didn't request those keys. The API will also include a mechanism for the KMP to receive requests for session keys and other parameters from the routing protocol. The KMP will also be aware of the various Base RPs and each of their unique parameters that need to be negotiated and returned. o KMP-KeyStore API - There will be an API for the KMP to place keys and parameters into the KeyStore after their negotiation and derivation with the other peer. This will enable the implementers to reuse the same calls for multiple KMPs that may be needed to address the various categories of RPs as described in the section definingcategories (Section 3). Lebovitz & Expires September 11, 2009 [Page 23] Internet-Draft KMART Roadmap March 2009 [after writing this all up, I'm not sure we really need the key_store in the middle. As long as we standardize fully all the calls needed from any RP to any KMP, then there can be a generic hand-down function from the KMP to the RP when the key and parameters are ready. Let's sleep on it.] [will need state machines and function calls for these APIs, as one of the work items. In essence, there is a need for a core team to develop the APIs out completely in order for the RP teams to use them. Need to get this team going asap.] o Identifiers - A KMP is fed by identities. The identities are text strings used by the peers to indicate to each other that each are known to the other, and authorized to establish connections. Those identities must be represented in some standard string format, e.g. an IP address -- either v4 or v6, an FQDN, an RFC 822 email address, a Common Name [RFC PKI], etc. Note that even though routers do not normally have email addresses, one could use an RFC 822 email address string as a formatted identifier for a router. They would do so simply by putting the router's reference number or name- code as the "NAME" part of the address, left of the "@" symbol. They would then place some locational context in the "DOMAIN" part of the string, right of the "@" symbol. An example would be "rtr0210@sf.ca.us.company.com". This document does not suggest this string value at all. Instead, the concept is used only to clarify that the type of string employed does not matter. It also does not matter what specific text you chose to place in that string type. It only matters that the type of string -- and it's format -- must be agreed upon by the two endpoints. Further, the string can be used as an identifier in this context, even if the string is not actually provisioned in it's source domain. For example, the email address "rtr0210@sf.ca.us.company.com" may not actually exist as an email address in that domain, but that string of characters may still be used as an identifier type(s) in the routing protocol security context. What is important is that the community decide on a small but flexible set of Identifiers they will all support, and that they decide on the exact format of those string. The formats that will be used must be standardized and must be sensible for the routing infrastructure. Lebovitz & Expires September 11, 2009 [Page 24] Internet-Draft KMART Roadmap March 2009 o Identity Proof - Once the form of identity is decided, then there must be a cryptographic proof of that identity, that the peer really is who they assert themselves to be. Proof of identity can be arranged between the peers in a few ways, for example pre-shared keys, raw assymetric keys, or a more user-friendly representation of assymetric keys, like a certificate. Certificates can be used in a way requiring no additional supporting systems -- e.g. public keys for each peer can be maintained locally for verification upon contant. Certificate management can be made more simple and scalable with the use minor additional supporting systems, as is the case with self-signed certificates and a flat file list of "approved thumbprints". Self-signed certificates will have somewhat lower security properties than Certificate Authority signed certificates [RFC Certs]. The use of these different identity proofs vary in ease of deployment, ease of ongoing management, startup effort, ongoing effort and management, security strength, and consequences from loss of secrets from one part of the system to the rest of the system. For example, they differ in resistance to a security breach, and the effort required to remediate the whole system in the event of such a breach. The point here is that there are options, many of which are quite simple to employ and deploy. o Profiles - Once the KMP, Identifiers and Proofs mechanisms are converged upon, they must be clearly profiled for each Base RP, so that implementors and deployers alike understand the different pieces of the solution, and can have similar configurations and interoperability across multiple vendors' devices, so as to reduce management difficulty. The profiles SHOULD also provide guidance on when to use which various combinations of options. This will, again, simplify use and interoperability. Common Mechanisms - In as much as they exist, the framework will capture mechanisms that can be used commonly not only within a particular category of Base RP and Base RP to KMP, but also between Base RP categories. Again, the goal here is simplifying the implementations and runtime code and resource requirements. There is also a goal here of favoring well vetted, reviewed, operationally proven security mechanisms over newly brewed mechanisms that are less well tried in the wild. Lebovitz & Expires September 11, 2009 [Page 25] Internet-Draft KMART Roadmap March 2009 4.4. Work Items Per Routing Protocol Each Base RP will have a team (the [RP]-KMART team) working on incrementally improving their Base RP's security, These teams will have the following main work items: PHASE 1: Characterize the RP Assess the Base RP to see what authentication mechanisms it has today. Does it needs significant improvement to its existing mechanisms or not? This will include determining if modern, strong security algorithms and parameters are present. Define Optimal State List the requirements for the Base RP's session key usage and format to contain to modern, strong security algorithms and mechanisms, per the Requirements (Section 4.2)section above. The goal here is to determine what is needed for they BaseRP alone to be used securely with at least manual keys. Gap Analysis Enumerate the requirements for this protocol to move from its current security state, the first bullet, to its optimal state, bullet two above. Define, Assign, Design Create a deliverables list of the design and specification work, with milestones. Define owners. Release a document(s) PHASE 2: KMP Analysis Review requirements for KMPs [RFC????]. Identify any nuances for this particular protocol's needs and its use cases for KMP. List the requirements that this RP has for being able to be use in conjunctions with a KMP. Define the optimal state. Gap Analysis Enumerate the requirements for this protocol to move from its current security state to its optimal state. Define, Assign, Design Lebovitz & Expires September 11, 2009 [Page 26] Internet-Draft KMART Roadmap March 2009 Create a deliverabels list of the design and specification work, with miletsones. Define owners. Do the design and document work for a KMP to be able to generate the Base RP's session keys for the packets on the wire. These will be the arguments passed in the API to the KMP in order to bootstrap the session keys to the Base RP. There will also be a team formed to work on the base framework mechanisms for each of the main categories, i.e. the blocks and API's represented in figure 1 (Figure 1). 4.5. Protocols in Categories This section groups the Base RPs into like categories, according to attributes set forth in Categories Section (Section 3). Each group will have a design team tasked with improving the security of the Base RP mechanisms and defining the KMP requirements for their group, then rolling both into a roadmap document upon which they will execute. BGP, LDP and MSDP The Base RP's that fall into the category of the one-to-one peering messages, and will use peer keying protocols, AND are all transmitted over TCP include BGP RFC 4271 [RFC4271], LDP [RFC5036] and MSDP [RFC3618]. A team will work on one mechanism to cover these three protocols. Much of the work on the BaseRP update for its existing authentication mechanism is already occuring in the TCPM Working Group, on the TCP-AO [I-D.ietf-tcpm-tcp-auth-opt] document, as well as its cryptography-helper document, TCP-AO-CRYPTO [I-D.ao-crypto]. The exception is the mode where LDP is used directly on the LAN [RFC????]. The work for this may go into the Group keying category (w/ OSPF) mentioned below. OSPF, ISIS, and RIP The Base RPs that fall into the category Group keying with one- to-many peering messages includes OSPF [RFC2328], ISIS [RFC1195] and RIP [RFC2453]. Not surprisingly, all these routing protocols have two other things in common. First, they are run on a combination of the OSI datalink layer 2, and the OSI network layer 3. Second, they are all internal gateway protocols, or IGPs. The keying mechanisms and use will be much more complicated to define for these. Lebovitz & Expires September 11, 2009 [Page 27] Internet-Draft KMART Roadmap March 2009 BFD Because it is less of a routing protocol, per se, and more of a peer aliveness detection mechanism, Bidirectional Forwarding Detection (BFD) [RFC????] will have its own team. RSVP [RFC????], RSVP-TE [RFC????], and PCE These three protocols will be handled together. [what more characterisation should we give here? Routing AD's, provide text pls?] PIM-SM and PIM-DM Finally, the multicast protocols of PIM-SM [RFC4601] and PIM-DM [RFC3973] will be handled together. PIM-SM multicasts routing information (Hello, Join/Prune, Assert) on a link-local basis, using a defined multicast address. In addition, it specifies unicast communication for exchange of information (Register, Register-Stop) between the router closest to a group sender and the "rendezvous point" (RP). The RP is typically not "on-link" for a particular router. While much work has been done on multicast security for application-layer groups, little has been done to address the problem of managing hundreds or thousands of small one-to-many groups with link-local scope. This will be necessary if we are to have unique keys per speaking router in a PIM chain. Such an authentication mechanism should be considered along with the router-to-Rendezvous Point authentication mechanism. The most important issue is ensuring that only the "legitimate neighbors" get the keys for (S,G), so that rogue routers cannot participate in the exchanges. Another issue is that some of the communication may occur intra-domain, e.g. the link-local messages in an enterprise, while others for the same (*,G) may occur inter-domain, e.g. the router-to-Rendezvous Point messges may be from one enterprise's router to another. One possible solution proposes a region-wide "master" key server (possibly replicated), and one "local" key server per speaking router. There is no issue with propagating the messages outside the link, because link-local messages, by definition, are not forwarded. This solution is offered only as an example of how work may progress; further discussion should occur in this work team. Specification of a link-local protection mechanism for PIM-SM occurred in RFC 4601 [RFC4601], and this work is being updated in PIM-SM-LINKLOCAL [I-D.ietf-pim-sm-linklocal]. However, the KMP part is completely unspecified, and will require work outside the expertise of the PIM working group to accomplish, which is why this roadmap is being created. Lebovitz & Expires September 11, 2009 [Page 28] Internet-Draft KMART Roadmap March 2009 These protocols are deemed out-of-scope for this current iteration of the work roadmap. Once all of the protocols listed above have had their work completed, or are clearly within site of completion, then the community will revisit the need and interest for working on these: o MANET o FORCES [need text from routing ADs on why these are out of scope] 4.6. Priorites Resources from both the routing area and the security area will be applied to work on these problem spaces as quickly as possible. Realizing that such resources are far from unlimited, a rank order priority for addressing the work of incrementally securing these groups of routing protocols is provided: o Priority 1 - BGP / LDP / MSDP o Priority 2 - BFD o Priority 3 - OSPF / ISIS / RIP o Priority 4 - RSVP and RSVP-TE By far the most important group is the Priority 1 group as these are the protocols used on the most public and exposed segments of the networks, at the peering points between operators and between operators and their customers. BFD, as a detection mechanism underlying the Priority 1 protocols is therefore second. 5. Security Considerations This entire document focuses on improving the security of routing protocols by improving or implementing cryptographic authentication for each routing protocol. Security considerations are largely contained within the body text of the document. The mechanisms that will be defined under this roadmap aim to improve the security, better protect against more threats, and provider far greater operational efficiencies than the state of things at the time of this writing. However, none of these changes will improve Internet security unless they are implemented and deployed. Other influences must be brought to bare upon operators and organizations to create incentives for deployment. Such incentives may take the form of PCI-like industry compliance/certifications, well advertised BCPs profiling the use of this roadmap's output, end-user demand or Lebovitz & Expires September 11, 2009 [Page 29] Internet-Draft KMART Roadmap March 2009 insistance. [we can pull pieces out of body and place here, if people think it more appropriate]. 6. IANA Considerations This document has no actions for IANA. 7. Acknowledgements The outline for this draft was created from discussions and agreements with Routing AD's Ross Callon and Dave Ward, Security AD's Tim Polk and Pasi Eronen, and IAB members Danny McPherson and Gregory Lebovitz. Mat Ford and Bill Atwood provided reviews to -00. 8. Change History (RFC Editor: Delete Before Publishing) [NOTE TO RFC EDITOR: this section for use during I-D stage only. Please remove before publishing as RFC.] -00-00 original rough rough rough draft for review by routing and security AD's -00- original submission o adds new category = multicast protocols in category section and mentions mcast in group keying category description. o add a lot of references where they did not exist before, or where there were only place holders. Still more work needed on this. o abstract filled in o changed from standards track to informational (this was an oversight in last draft). o filled out threats section with detailed descriptions, and linked to RPsec threats RFC o made ascii art for the basic KMP framework o added section on internal versus external peering and the requirements decisions for them o added security characterization section in sect 2, added sections discussing internal vs external protocols, shared vs unique keys, oob vs in-band keying Lebovitz & Expires September 11, 2009 [Page 30] Internet-Draft KMART Roadmap March 2009 o incorporates all D Ward's feedback from his initial skim of the document. -01- o Updated framework (Figure 1) diagram to include all listed and described elements. Needs review and honing. Gregory Lebovitz (GL). o Added comment in protocols (Section 4.5) section that much of the BGP/LDP Phase 1 work is already being done in tcp-ao and ao- crypto. GL. o Updated Scope making the 2 work phases more clear earlier in the document. GL. o Broke work items (Section 4.4) section into two Phases, 1 for manual key update, and second for KMP work. GL. o Re-org'd doc. Brought Threats (Section 2) section out into its own top-level section. Did same with Categorization (Section 3) section, leaving Roadmap section more focused. Moved ToDo list and Change History to end of doc, after Acknowledgements. GL. o added new sect 2.3 (Section 4.1) on main roadmap phases. Previous section Common Framework (Section 4.3) moved to 2.4. Tim Polk (TP). o Added Section 2.3.1 Requirements for Phase 1 BaseRPs' Security Update (Section 4.2). This provides a nice starter set of requirements for any work team. GL. o Filled out text for Out vs In-band Key Mgmt (Section 3.3.3) section, significantly. Changed the term from "in-band" to "in- line". o Section Threats (Section 2) Clarified DoS threats in and out of scope better. We are not preventing all DoS attacks. Just those we can reasonably via authentication. TP. o Sect In-band vs Out-of-Band (Section 3.3.3)clarified that In-band does not mean in-band to RP, but rather over IP between the RPs, rather than pushed down by some external management entity. TP. o In roadmap (Section 3) section, added "it is also hoped that we can create one kmp per category..." Also explained value of a KMP. TP. o Added "operators" to audience (Section 1.6) list. Matt Ford (MF). o Described why BGP (and LDP) security is not deployed very often. Added this Scope (Section 1.3) section, point 4. If mechanisms aren't being deployed, why is that? What, if anything, could be done to improve deployment? Tried to address these. Need references (see To Do list below). MF. o Added some text to security section to address this from MF: say something here about the limitations of this approach, if any - and refer back to the need for other pieces of the puzzle. May need more work. Lebovitz & Expires September 11, 2009 [Page 31] Internet-Draft KMART Roadmap March 2009 o Cleaned up text for multicast part of Message Type (Section 3.1) section and Protocols (Section 4.5) section, clarifying PIM's two message types, mcast and unicast, in both places. Bill Atwood (BA). o In section Protocols (Section 4.5), added references to 4601 and PIM-SM-LINKLOCAL. BA. o Editorial changes pointed out various folks. 9. Needs Work in Next Draft (RFC Editor: Delete Before Publishing) [NOTE TO RFC EDITOR: this section for use during I-D stage only. Please remove before publishing as RFC.] List of stuff that still needs work o RTG AD's or delegates: clean up the three definitions of route message type categories. Need RTG Area folks input on this. o More clarity on the work items for those defining and specifying the framework elements and API's themselves. o RTG AD's or delegates: text justifying RSVP and RSVP-TE and what we thing solving that problem may look like o RTG AD's or delegates: more justification for why MANET and FORCES are out of scope. Need ref for those RFCs. o Danny McPherson: Get reference for BGP auth usage stats in Scope (Section 1.3) section, item 4. o Get RFC references and insert where not done yet o security section? Still nees more there, I think? o 10. References 10.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4593] Barbir, A., Murphy, S., and Y. Yang, "Generic Threats to Routing Protocols", RFC 4593, October 2006. [RFC4948] Andersson, L., Davies, E., and L. Zhang, "Report from the IAB workshop on Unwanted Traffic March 9-10, 2006", RFC 4948, August 2007. 10.2. Informative References [I-D.ao-crypto] Lebovitz, G., "Cryptographic Algorithms, Use and Lebovitz & Expires September 11, 2009 [Page 32] Internet-Draft KMART Roadmap March 2009 Implementation Requirements for TCP Authentication Option", March 2009, . [I-D.ietf-pim-sm-linklocal] Atwood, W., Islam, S., and M. Siami, "Authentication and Confidentiality in PIM-SM Link-local Messages", draft-ietf-pim-sm-linklocal-07 (work in progress), February 2009. [I-D.ietf-tcpm-tcp-auth-opt] Touch, J., Mankin, A., and R. Bonica, "The TCP Authentication Option", draft-ietf-tcpm-tcp-auth-opt-04 (work in progress), March 2009. [RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and dual environments", RFC 1195, December 1990. [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. [RFC2453] Malkin, G., "RIP Version 2", STD 56, RFC 2453, November 1998. [RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC Text on Security Considerations", BCP 72, RFC 3552, July 2003. [RFC3618] Fenner, B. and D. Meyer, "Multicast Source Discovery Protocol (MSDP)", RFC 3618, October 2003. [RFC3973] Adams, A., Nicholas, J., and W. Siadak, "Protocol Independent Multicast - Dense Mode (PIM-DM): Protocol Specification (Revised)", RFC 3973, January 2005. [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006. [RFC4301] Kent, S. and K. Seo, "Security Architecture for the Internet Protocol", RFC 4301, December 2005. [RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", RFC 4303, December 2005. [RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", RFC 4306, December 2005. [RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas, "Protocol Independent Multicast - Sparse Mode (PIM-SM): Lebovitz & Expires September 11, 2009 [Page 33] Internet-Draft KMART Roadmap March 2009 Protocol Specification (Revised)", RFC 4601, August 2006. [RFC4949] Shirey, R., "Internet Security Glossary, Version 2", RFC 4949, August 2007. [RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP Specification", RFC 5036, October 2007. [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008. Authors' Addresses Gregory Lebovitz Juniper Networks, Inc. 1194 North Mathilda Ave. Sunnyvale, CA 94089-1206 US Phone: Email: gregory.ietf@gmail.com Phone: Email: Lebovitz & Expires September 11, 2009 [Page 34]