Internet DRAFT - draft-ietf-pana-snmp
draft-ietf-pana-snmp
PANA Working Group Y. El Mghazli
Internet-Draft Alcatel
Expires: December 25, 2006 Y. Ohba
Toshiba
J. Bournelle
GET/INT
June 23, 2006
SNMP usage for PAA-EP interface
draft-ietf-pana-snmp-06
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Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
The PANA Authentication Agent (PAA) does not necessarily act as an
Enforcement Point (EP) to prevent unauthorized access or usage of the
network. When a PANA Client successfully authenticates itself to the
PAA, EP(s) (e.g., access routers) will need to be suitably notified.
The PANA working group recommends the use of Simple Network
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Management Protocol Version 3 (SNMPv3) to deliver the authorization
information to one or more EPs when the PAA is separated from EPs.
The present document provides the necessary information and
extensions needed to use SNMPv3 as the PAA-EP protocol.
Table of Contents
1. Terminology and Definitions . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. PAA/EP separation context . . . . . . . . . . . . . . . . 5
2.2. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3. The Internet-Standard Management Framework . . . . . . . . . . 7
4. SNMP Applicability with the PANA framework . . . . . . . . . . 8
4.1. SNMPv3 General applicability . . . . . . . . . . . . . . . 8
4.2. Compliancy of SNMP against the PANA requirements . . . . . 9
4.2.1. Authorization Consideration . . . . . . . . . . . . . 9
4.2.2. PAA-EP relation . . . . . . . . . . . . . . . . . . . 10
4.2.3. Secure Communication . . . . . . . . . . . . . . . . . 10
4.2.4. Notification of PaC presence . . . . . . . . . . . . . 10
4.2.5. Accounting Consideration . . . . . . . . . . . . . . . 11
4.2.6. Peer Liveness Test and Rebooted Peer Detection . . . . 11
5. Applicability of IPsec configuration MIBs . . . . . . . . . . 13
5.1. General IP Access Control . . . . . . . . . . . . . . . . 13
5.2. Network Layer Secure Access Control (IPsec) . . . . . . . 14
6. PANA extension to the IPsec SPD MIB . . . . . . . . . . . . . 17
6.1. Bootstrapping link layer ciphers . . . . . . . . . . . . . 17
6.2. Notification of PaC presence . . . . . . . . . . . . . . . 17
6.3. PANA MIB Overview . . . . . . . . . . . . . . . . . . . . 18
6.4. PANA MIB Objects Definition . . . . . . . . . . . . . . . 19
7. Applicability of RTFM Meter MIB . . . . . . . . . . . . . . . 29
8. EP Configuration Example . . . . . . . . . . . . . . . . . . . 30
8.1. Common setup . . . . . . . . . . . . . . . . . . . . . . . 30
8.2. General IP-based Access Control . . . . . . . . . . . . . 32
8.3. IPsec-based Access Control . . . . . . . . . . . . . . . . 33
8.4. Link-layer Access control . . . . . . . . . . . . . . . . 37
9. Security Considerations . . . . . . . . . . . . . . . . . . . 39
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 42
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 43
12.1. Normative References . . . . . . . . . . . . . . . . . . . 43
12.2. Informative References . . . . . . . . . . . . . . . . . . 44
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 46
Intellectual Property and Copyright Statements . . . . . . . . . . 47
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1. Terminology and Definitions
PANA: Protocol for Carrying Authentication for Network Access.
PaC (PANA Client):
The client side of the protocol that resides in the host device,
which is responsible for providing the credentials to prove its
identity for network access authorization. A PaC is responsible
for requesting network access and engaging in authentication
process using the PANA protocol.
DI (Device Identifier):
The identifier used by the network as a handle to control and
police the network access of a client. Depending on the access
technology, this identifier might contain any of IP address, link-
layer address, switch port number, etc. of a connected device.
PAA (PANA Authentication Agent):
The access network (server) side entity of the PANA protocol. A
PAA is in charge of interfacing with the PaCs for authenticating
and authorizing them for the network access service. To this end,
the PAA verifies the credentials provided by a PANA client and
grants network access service to the device associated with the
client and identified by a DI.
The PAA is also responsible for updating the access control state
(i.e., filters) depending on the authorization. The PAA
communicates the updated state to the enforcement points in the
network. When the PAA and the EP are separated, a protocol is
required to carry the authorized client attributes from the PAA to
the EP. SNMPv3 is used to this end.
EP (Enforcement Point):
A node on the access network where per-packet enforcement policies
are applied on the inbound and outbound traffic of client devices.
The EP uses non-cryptographic or cryptographic filters to
selectively allow and discard data packets. These filters may be
applied at the link-layer or the IP-layer. An EP learns the
attributes of the authorized clients (DI and optionally
cryptographic keys) from the PAA.
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Authentication Server (AS):
The server implementation that is in charge of verifying the
credentials of a PaC that is requesting the network access
service. The AS receives requests from the PAA on behalf of the
PaCs, and responds with the result of verification together with
the authorization parameters (e.g., allowed bandwidth, IP
configuration, etc). The AS might be hosted on the same node as
the PAA, on a dedicated node on the access network, or on a
central server somewhere in the Internet.
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2. Introduction
2.1. PAA/EP separation context
PANA enables access control by identifying legitimate clients and
generating filtering information for access control mechanisms.
[I-D.ietf-pana-framework] defines a general AAA and access control
framework. The PANA protocol itself provides client authentication
and authorization functionality for securing network access. Access
control ensures that only authenticated and authorized clients can
gain access to the network.
Access control can be achieved by placing EPs (Enforcement Points) in
the network for policing the traffic flow. EPs should prevent data
traffic from and to any unauthorized client unless it's either PANA
or one of the other allowed traffic types (e.g., ARP, IPv6 neighbor
discovery, DHCP, etc.).
Figure 1 below illustrates the functional entities and the interfaces
(protocols, APIs) among them.
RADIUS/
Diameter/
+-----+ PANA +-----+ LDAP/ API +-----+
| PaC |<----------------->| PAA |<---------------->| AS |
+-----+ +-----+ +-----+
^ ^
| |
| +-----+ |
IKE/ +-------->| EP |<--------+ SNMP/ API
4-way handshake +-----+
Figure 1: PANA Functional Model
Some of the entities may be co-located depending on the deployment
scenario.
The EP on the access network allows general data traffic from any
authorized PaC, whereas it allows only limited type of traffic (e.g.,
PANA, DHCP, router discovery) for the unauthorized PaCs. This
ensures that the newly attached clients have the minimum access
service to engage in PANA and get authorized for the unlimited
service.
If the PaC is authorized to gain the access to the network, the PAA
also sends the PaC-specific attributes (e.g., IP address,
cryptographic keys, etc.) to the EP by using SNMP. The EP uses this
information to enforce policy rules allowing data traffic from and to
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the PaC to pass through.
In case a cryptographic access control needs to be enabled after the
PANA authentication, a secure association protocol runs between the
PaC and the EP. The PaC should already have the input parameters to
this process as a result of the successful PANA exchange. Similarly,
the EP should have obtained them from the PAA via SNMP. Secure
association exchange produces the required security associations
between the PaC and the EP to enable per-packet protection.
Finally data traffic can start flowing from and to the newly
authorized PaC.
In this document, it is assumed that PAA and EP are pre-configured to
be able to communicate each other with a required security
association. In case where dynamic discovery is needed for PAA and
EP to know each other's address, then SNMPv3 engine-id discovery
could be used. Such dynamic discovery is out of scope of this
document.
2.2. Scope
Section 3 gives references for the SNMP framework.
Section 4 provides a general statement with regards to the
applicability of SNMP as the PAA-EP protocol.
IPsec configuration MIB modules were found to have general
applicability and varying levels of re-usability for PANA EP
authorization configuration using SNMP. Section 5 details the
applicability of this MIB set to the EP configuration and Section 6
defines some additional PANA-specific objects that extend the IPsec
SPD-MIB module [I-D.ietf-ipsp-spd-mib] in order to entirely satisfy
the PAA-EP interface requirements.
In the same manner, RTFM Meter MIB module was found to have general
applicability of re-usability for PANA EP accounting configuration
using SNMP. Section 7 details the applicability of this MIB to the
EP configuration.
Finally, Section 9 addresses the security considerations.
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3. The Internet-Standard Management Framework
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
[RFC3410].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58
[RFC2578], STD 58 [RFC2579] and STD 58 [RFC2580].
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4. SNMP Applicability with the PANA framework
This section provides a general statement with regards to the
applicability of SNMP as the PAA-EP protocol. This analysis of SNMP
is specific to SNMPv3, which provides the security required for PANA
usage. SNMPv1 and SNMPv2c would be inappropriate for PANA since they
have been declared Historic, and because their messages have only
trivial security.
4.1. SNMPv3 General applicability
SNMPv3 is that it is a mature, well understood protocol, currently
deployed in various scenarios, with mature toolsets available for
SNMP managers and agents.
Application intelligence is captured in MIB modules, rather than in
the messaging protocol. MIB modules define a data model of the
information that can be collected and configured for a managed
functionality. The SNMP messaging protocol transports the data in a
standardized format without needing to understand the semantics of
the data being transferred. The endpoints of the communication
understand the semantics of the data.
Partly due to the lack of security in SNMPv1 and SNMPv2c, and partly
due to variations in configuration requirements across vendors, few
MIB modules have been developed that enable standardized
configuration of managed devices across vendors. Since monitoring
can be done using only a least-common-denominator subset of
information across vendors, many MIB modules have been developed to
provide standardized monitoring of managed devices. As a result,
SNMP has been used primarily for monitoring rather than for
configuring network nodes.
SNMPv3 builds upon the design of widely-deployed SNMPv1 and SNMPv2c
versions. Specifically, SNMPv3 shares the separation of data
modeling (MIBs) from the protocol to transfer data, so all existing
MIBs can be used with SNMPv3. SNMPv3 also uses the SMIv2 standard,
and it shares operations and transport with SNMPv2c. The major
difference between SNMPv3 and earlier versions is the addition of
strong message security and controlled access to data.
SNMPv3 uses the architecture detailed in [RFC3411], where all SNMP
entities are capable of performing certain functions, such as the
generation of requests, response to requests, the generation of
asynchronous notifications, the receipt of notifications, and the
proxy-forwarding of SNMP messages. SNMP is used to read and
manipulate virtual databases of managed-application-specific
operational parameters and statistics, which are defined in MIB
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modules.
4.2. Compliancy of SNMP against the PANA requirements
The following sections detail how the PAA-EP protocol requirements
are fully supported by SNMP:
4.2.1. Authorization Consideration
This section discusses PAA-EP communication in terms of authorization
aspects.
Binary Authorization:
Filtering rules to be installed on EP generally include a device
identifier of PaC, and also some cryptographic keying materials
(e.g., IKE [RFC2409] pre-shared key ) when cryptographic data
traffic protection is needed. Each keying material is uniquely
identified with a keying material name (e.g., ID_KEY_ID in IKE)
and has a lifetime for key management, accounting, access control
and security reasons in general.
PANA authorization management can be modeled in a way that is
consistent with existing standard MIB modules, this is detailed in
Section 5. Additional PANA-specific objects may be needed and are
defined in Section 6.
Profile-based authorization:
In addition to the device identifier and keying material, the PAA
may provide the EP with additional authorization information. For
instance, a user may be authorized to access the network within a
given class of service or for a maximum amount of units. The type
of units can be time (e.g., authorization lifetime), volume (e.g.,
the number of incoming and/or outgoing packets and/or bytes),
service specific or money depending on the type of service event
[I-D.ietf-aaa-diameter-cc].
This type of authorization might also require that the
communicating pair of PAA and EP to detect a dead or rebooted peer
in order to avoid possible inaccurate accounting. This aspect is
discussed in Section 4.2.6.
In any case, even if it is very likely to occur between the PAA
and EP, this kind of profile-based authorization is beyond the
scope of the PANA working group. Hence, the specification of the
MIB modules (existing or not) necessary to provide such policy
information is outside the scope of the present document, which
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deals only with the so-called binary authorization.
4.2.2. PAA-EP relation
A number of deployment options are envisaged within the PANA
framework. See [I-D.ietf-pana-framework] for further details.
The SNMP framework [RFC3410] supports one-to-many, many-to-one, and
many-to-many relationships between the SNMP managers (PAAs) and
agents (EPs).
4.2.3. Secure Communication
SNMPv3 includes the User-based Security Model (USM, [RFC3414]), which
provides authentication, confidentiality, and integrity.
Additionally, USM has specific built-in mechanisms for preventing
replay attacks including unique protocol engine IDs, timers and
counters per engine and time windows for the validity of messages.
See [RFC3410] for the security features provided by the SNMPv3
framework.
4.2.4. Notification of PaC presence
The PaC may also choose to start sending packets before getting
authenticated. In that case, the network should detect this and the
PAA must send an unsolicited PANA-Start-Request message to the PaC.
The EP is the node that can detect such activity. In case they are
separate, there needs to be an explicit message to prompt the PAA.
Such a presence notification is done by using the SNMP notification
operation. See Section 6 and Section 6.2 for details on how new and
existing SNMP objects provide this feature.
The presence notification may contain both an IP address and a link-
layer address, or only one of them.
A presence notification without containing a link-layer address may
be generated where access control is performed using IPsec [I-D.ietf-
pana-ipsec].
A presence notification without containing an IP address may be
generated when a link-layer frame that does not contain an IP address
is used as the notification trigger. If the PAA that received such a
notification from the EP has already a PANA session associated with
the link-layer address, it may use the notification as a trigger to
install filtering information to the EP. This can happen if the PaC
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is roaming from one EP to another under the same PAA.
4.2.5. Accounting Consideration
Since authentication and authorization are closely related to
accounting in many cases, accounting aspects need to be considered in
the PAA-EP protocol.
The PAA device acts as an accounting client of a AAA protocol. The
PAA collects accounting information from the EP(s) it controls, and
sends the gathered data to the accounting server by using the AAA
protocol.
PANA accounting management can be done using RTFM (Real-Time Flow
Measurement) standard MIB module [RFC2720], this is detailed in
Section 7.
The authentication/authorization session identifier of a AAA protocol
is used by the accounting server to associate accounting information
with a particular authentication/authorization session to calculate
bills. The authentication/authorization session identifier may or
may not be the same as the PANA session identifier and it is the
responsibility of the PAA to organize the correlation between the
meters/filters at the EP and the PANA/AAA sessions at the PAA.
The communicating pair of the PAA and the EP might need to detect a
rebooted peer to avoid possible inaccurate accounting. This aspect
is discussed in Section 4.2.6.
4.2.6. Peer Liveness Test and Rebooted Peer Detection
PAA-EP protocol implementations need to be stateful, when considering
the authorization and accounting aspects as described in the previous
sections. The stateful nature provides the functionality to detect a
dead or rebooted peer in a timely fashion. On the other hand, this
does not mean that the PAA-EP protocol itself needs to be stateful.
For example, an SNMP entity (i.e., an SNMP engine plus SNMP
applications) can generate SNMP queries on a particular MIB at an
interval short enough to perform peer liveness test and rebooted peer
detection.
Also, the peer liveness test and rebooted peer detection need to be
performed securely.
When SNMPv3 is used as the PAA-EP protocol, the SNMP management
framework supports snmpEngineBoots MIB [RFC3411]. By periodically
sending SNMP query to the peer to check the current value of this MIB
with the use of SNMP Security Subsystem, it is possible for an SNMP
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entity to securely perform peer liveness test and rebooted peer
detection between PAA and EP.
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5. Applicability of IPsec configuration MIBs
This section details the applicability of existing IPsec
configuration MIB modules to the EP configuration. These were found
to have general applicability and a fair level of re-usability for
the PANA EP configuration:
IPSec Security Policy Database (SPD) Configuration MIB:
[I-D.ietf-ipsp-spd-mib] defines a MIB module (IPSEC-SPD-MIB) for
configuration of an IPSec Security Policy Database (SPD). No
IPsec or IKE specific actions are defined within this document.
IPsec Security Policy IKE Action MIB:
[I-D.ietf-ipsp-ikeaction-mib] defines a MIB module (IPSEC-
IKEACTION-MIB) for configuration of an IKE action within the IPsec
SPD.
IPsec Security Policy IPsec Action MIB:
[I-D.ietf-ipsp-ipsecaction-mib] defines a MIB module (IPSEC-
IPSECACTION-MIB) for configuring IPsec actions within the IPsec
SPD.
The EP enforces binary authorization by filtering data traffic on the
basis of the Device Identifier (DI) of the PaC. The PAA must
provision its EPs with DI-based filters in order to control and
police the network access of a PaC. According to the definition of
the Device Identifier in [RFC4058], such filters - depending on the
access technology - might be either a IPv4/6 address or a link-layer
address of a connected device.
Do note also that a keying material might be provisioned. The
particular case where access control is performed using IPsec is
specified in [I-D.ietf-pana-ipsec]. The configuration aspects in
this case are detailed in Section 5.2.
5.1. General IP Access Control
The IPsec SPD MIB module (SPD-MIB) is designed to configure an IPsec
security policy database in a policy and rule oriented fashion. This
module is divided into 3 portions (Rules, Filters, Actions).
Specifically, SPD-MIB provides a generic mechanism for performing
packet processing based on a rule set.
The policy-based packet filtering and the corresponding execution of
actions is of a more general nature than for IPsec configuration
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only, such as for configuration of a firewall. Rules within the
IPsec SPD-MIB are generic and simply bind a filter to an action.
Filters provided within the SPD-MIB itself are numerous and fairly
complete for most common packet filtering usage but externally
defined filters are supported.
For IPv4/v6 address-based filters provisioning, the DIFFSERV-MIB
module defined in [RFC3289] provides means to filter the traffic
based on the IP header information. DiffServ Multi-field Classifier
table provides such facilities: one can define the various tests that
are used when evaluating a given IP packet. The various tests
definable in this table are as follows:
o IP source address prefix, including host, CIDR Prefix, and "any
source address"
o IP destination address prefix, including host, CIDR Prefix, and
"any destination address"
o IPv6 Flow ID
o IP protocol or "any"
o TCP/UDP/SCTP source port range, including "any"
o TCP/UDP/SCTP destination port range, including "any"
o Differentiated Services Code Point
The results of each test are ANDed together to produce the result of
the entire filter.
The actions encapsulated within the SPD-MIB module are basic drop/
accept actions. These are sufficient to perform EP binary
authorization enforcement at the EP.
When profile-based authorization information is provided to the EP,
more advanced actions like classifiers, meters and schedulers might
be configured by the PAA. This is out of the scope of the present
document.
5.2. Network Layer Secure Access Control (IPsec)
The PANA protocol authenticates the client and also establishes a
PANA security association between the PANA client and PANA
authentication agent at the end of successful authentication. The
PAA indicates the results of the authentication using the PANA-Bind-
Request (PBR) message wherein it can indicate the access control
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method enforced by the access network and the IP address of the
corresponding EP.
When IPsec is used to perform access control, the PANA protocol
[I-D.ietf-pana-pana] does not discuss any details of IPsec [RFC2401]
SA establishment. Indeed, [I-D.ietf-pana-ipsec] discusses the
details for establishing IPsec security associations between the PaC
and the EP. When the IPsec SAs are successfully established, it can
be used to enforce access control and specifically used to prevent
the service theft mentioned in [RFC4016].
In this particular context, one assumes that the following have
already happened before the IPsec SAs are established:
1. PANA client (PaC) and PAA mutually authenticate each other using
EAP methods that derive the AAA-Key [I-D.ietf-eap-keying].
2. PaC learns the IP address of the Enforcement point (EP) during
the PANA exchange.
3. PaC learns that the network uses IPsec [RFC2401] for securing the
link between PaC and EP during the PANA exchange (PBR message).
4. PaC configures an IP address address before the PANA protocol
begins (the pre-PANA Address (PRPA), see [I-D.ietf-pana-pana]).
The IPsec IKE Action MIB module (IKEACTION-MIB) works within the
framework of the IPsec SPD-MIB. It can be referenced as an action by
the SPD-MIB and is used to configure IKE negotiations between network
devices. Hence, together with the SPD-MIB, the IKEACTION-MIB module
enables the PAA to configure IPSEC-based access control at the EP.
The PAA is then responsible to communicate to EP the following
information before IKE phase 1 exchange begins between PaC and EP:
The IKE pre-shared key:
To this end, the PAA must set a row in the IKE Credential Filter
table of the IKEACTION-MIB. This table defines filters, which can
be used to match credentials of IKE peers, where the credentials
in question have been obtained from an IKE phase 1 exchange. They
may be X.509 certificates, Kerberos tickets, or Pre-shared keys,
etc.
The PRPA of the PaC:
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The DiffServ Multi-Field Classifier of the DIFFSERV-MIB is used
for configuring the SPD in a similar manner than what is described
in Section 5.1.
The Key-Id and PANA session ID:
[I-D.ietf-pana-ipsec] states that PaC and EP should use the PANA
session ID concatenated with the AAA-key as the value of the
ID_KEY_ID in aggressive mode for establishing the phase 1 SA.
Section 8 details usage examples that illustrate the way the
IKEACTION-MIB is used for this purpose.
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6. PANA extension to the IPsec SPD MIB
Many existing MIB objects defined in the IPsec Configuration MIB
modules can be efficiently re-used for the PANA-specific needs. This
is detailed in Section 5.
The present section defines additional PANA-specific objects that
extend the IPsec SPD MIB module in order to entirely satisfy the
PAA-EP interface requirements.
6.1. Bootstrapping link layer ciphers
PANA can bootstrap not only network layer secure access control but
also any type of link layer secure access control. The following
parameters are defined to support bootstrapping link layer secure
access control:
panaL2FiltPmk:
A PMK (Pairwise Master Key) that is derived from AAA-Key and used
as the shared secret needed for executing a secure association
protocol between the PaC and EP in order to generate TSKs
(Transient Session Keys) [I-D.ietf-eap-keying]. In the case of
IEEE 802.11i [802.11i], an 802.11i PMK is carried in this MIB
object.
PMK Name:
The name fo the PMK. In the case of IEEE 802.11i, a 802.11i PMKID
is carried in this MIB object.
PMK Lifetime:
The lifetime of the PMK. The PMK must be invalidated when the PMK
lifetime expires. A new PMK with a new PMK lifetime may be
installed before the lifetime of the current PMK expires. The PMK
lifetime may be calculated from a RADIUS Session-Timeout attribute
or a Diameter Authorization-Lifetime AVP.
These parameters are contained in PanaL2FilterEntry together with
other link layer filtering parameters.
6.2. Notification of PaC presence
The SPD-MIB provides a means to notify to the SNMP manager (PAA)
information on packets matching/not matching the filters of given
rule. Such notification mechanisms and objects can be re-used for
notifying the PAA that unauthorized packets are trying to pass
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through the EP.
If reliability needs to be guaranteed for the notification
(panaNewPacNotification), hence Inform notification (which is
acknowledged) MUST be used. Then the PAA needs to have engine-id to
be the authoritative of SNMP clock between EP and PAA (for inform
operation the responder becomes the authoritative).
6.3. PANA MIB Overview
Link-Layer filter table
[I-D.ietf-pana-pana] says the Device-Id AVP (code 1025) is of
Address Type [RFC3588]. The content for link-layer addresses is
expected to be specified in specific documents that describe how
IP operates over different link-layers. For instance, IPv6 over
Ethernet is described in [RFC2464]. To this end, additional
filters are designed in the present document. The link-layer
filter test the L2 address (e.g. MAC address, port, DSL line) and
also defines a set of parameters needed for bootstrapping link-
layer ciphering, including a PMK (Pair-wise Master Key), the PMK
name and the PMK lifetime. Note that the definition of this table
does not assume the usage of any particular link-layer.
When the MIB module definition for a particular link-layer defines
MIB objects for the parameters specific to that link-layer, the
link-layer specific parameters SHOULD be accessed via the PANA MIB
using the link-layer filter table, instead of accessing them via
the link-layer specific MIB.
New PaC notification tables
This table defines a new notification, which aims at satisfying
this requirement. It re-uses existing notification variable
objects pre-defined in the SPD-MIB.
The "New PaC" notification is triggered when the EP detects
traffic coming from an unauthorized source.
If the traffic detected is an IP flow, the objects sent must
include spdIPSourceType, spdIPSourceAddress, spdIPDestinationType,
and spdIPDestinationAddress objects to indicate the packet source
and destination of the packet that triggered the action.
Additionally, the spdIPInterfaceType and spdIPInterfaceAddress
objects are included to indicate which interface the action was
executed in association with and if the packet was inbound or
outbound through the endpoint. See [I-D.ietf-ipsp-spd-mib] for
further details.
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If the traffic detected is Link-layer traffic, the objects sent
must include the index of the interface which detected such
traffic and potentially the L2 address source of the traffic.
6.4. PANA MIB Objects Definition
PANA-EP-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE
FROM SNMPv2-SMI
TEXTUAL-CONVENTION, RowStatus, PhysAddress, StorageType,
TimeStamp, TimeInterval
FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF
InterfaceIndex
FROM IF-MIB
spdMIB, spdIPEndpointAddType, spdIPEndpointAddress,
spdActionExecuted, spdIPSourceType, spdIPSourceAddress,
spdIPDestinationType,spdIPDestinationAddress
FROM IPSEC-SPD-MIB;
--
-- Module identity
--
panaMIB MODULE-IDENTITY
LAST-UPDATED
"200605280000Z" -- 28 may 2006
ORGANIZATION
"IETF PANA Working Group"
CONTACT-INFO
"Yacine El Mghazli
Alcatel
Route de Nozay
91460 Marcoussis
France
Email: yacine.el_mghazli@alcatel.fr
Yoshihiro Ohba
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Toshiba America Research, Inc.
1, Telcordia Drive
Piscataway, NJ 08854
USA
Email: yohba@tari.toshiba.com"
DESCRIPTION
"The MIB module for defining additional PANA-specific objects to
the IPsec SPD MIB. Copyright (C) The Internet Society (2003).
This version of this MIB module is part of RFC XXXX, see the
RFC itself for full legal notices."
-- Revision History
REVISION
"200605280000Z" -- 28 may 2006
DESCRIPTION
"Removed L2 notif"
REVISION
"200512280000Z" -- 22 december 2005
DESCRIPTION
"L2 Filter indexing modified"
REVISION
"200506280000Z" -- 28 Juin 2005
DESCRIPTION
"L2 protection generic parameters"
REVISION
"200502050000Z" -- 05 February 2005
DESCRIPTION
"L2 generic filters"
REVISION
"200410220000Z" -- 22 October 2004
DESCRIPTION
"Version 02, draft-ietf-pana-snmp-02.txt"
REVISION
"200402050000Z" -- 05 February 2004
DESCRIPTION
"Version 01, draft-yacine-pana-paa2ep-snmp-01.txt"
REVISION
"200310310000Z" -- 31 October 2003
DESCRIPTION
"Initial version, draft-yacine-pana-paa2ep-snmp-00.txt"
::= { spdMIB XXX } -- XXX to be assigned by IANA
--
-- groups of related objects
--
panaConfigObjects OBJECT IDENTIFIER
::= { panaMIB 1 }
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panaNotificationObjects OBJECT IDENTIFIER
::= { panaMIB 2}
panaConformanceObjects OBJECT IDENTIFIER
::= { panaMIB 3 }
--
-- Textual Conventions
--
PanaKey ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"The PanaKey is used to carry a key. When the key does
not exist, the length of the key becomes zero."
SYNTAX OCTET STRING (SIZE(0..255))
PanaKeyName ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"The PanaKeyName is used to carry the name of a PanaKey.
When the key name does not exist, the length of the
key name becomes zero."
SYNTAX OCTET STRING (SIZE(0..255))
--
-- PANA Additional Filters Objects
--
--
-- The Link-layer Filter Table
--
panaL2FilterTable OBJECT-TYPE
SYNTAX SEQUENCE OF PanaL2FilterEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Link-layer filter definitions."
::= { panaConfigObjects 1 }
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panaL2FilterEntry OBJECT-TYPE
SYNTAX PanaL2FilterEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the Link-layer filter table."
INDEX { panaL2FiltEpIfIndex, panaL2FiltAddr }
::= { panaL2FilterTable 1 }
PanaL2FilterEntry ::= SEQUENCE {
panaL2FiltEpIfIndex InterfaceIndex,
panaL2FiltAddr PhysAddress,
panaL2FiltPmk PanaKey,
panaL2FiltPmkName PanaKeyName,
panaL2FiltPmkLifetime TimeInterval,
panaL2FiltLastChanged TimeStamp,
panaL2FiltStorageType StorageType,
panaL2FiltRowStatus RowStatus
}
panaL2FiltEpIfIndex OBJECT-TYPE
SYNTAX InterfaceIndex
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The index identifying the EP interface where the filter
policy must be enforced on."
::= { panaL2FilterEntry 1 }
panaL2FiltAddr OBJECT-TYPE
SYNTAX PhysAddress
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The authorized device Link-layer address (DI). For
example, for a 802.x interface, this object normally
contains a MAC address. For interfaces which do not have such
an address (e.g., a serial line), this object should contain
an octet string of zero length."
::= { panaL2FilterEntry 2 }
panaL2FiltPmk OBJECT-TYPE
SYNTAX PanaKey
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This is PMK (Pairwise Master Key) used for bootstraping
link-layer ciphers."
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::= { panaL2FilterEntry 3 }
panaL2FiltPmkName OBJECT-TYPE
SYNTAX PanaKeyName
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This is the name of the panaL2Pmk."
::= { panaL2FilterEntry 4 }
panaL2FiltPmkLifetime OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This is the lifetime of panaL2Pmk."
::= { panaL2FilterEntry 5 }
panaL2FiltLastChanged OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime when this row was last modified or
created either through SNMP SETs or by some other external
means."
::= { panaL2FilterEntry 6 }
panaL2FiltStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this row. Rows in this table which were
created through an external process may have a storage type
of readOnly or permanent."
DEFVAL { nonVolatile }
::= { panaL2FilterEntry 7 }
panaL2FiltRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This object indicates the conceptual status of this row."
::= { panaL2FilterEntry 8 }
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--
--
-- Notification objects information
--
--
panaNotificationVariables OBJECT IDENTIFIER ::=
{ panaNotificationObjects 1 }
panaNotifications OBJECT IDENTIFIER ::=
{ panaNotificationObjects 0 }
panaEpIfIndex OBJECT-TYPE
SYNTAX InterfaceIndex
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"Contains the interface index on which the packet triggered
the notification in question."
::= { panaNotificationVariables 1 }
panaL2SourceAddress OBJECT-TYPE
SYNTAX PhysAddress
MAX-ACCESS accessible-for-notify
STATUS current
DESCRIPTION
"Contains the source Link layer address of the packet which
triggered the notification in question. For
example, for a 802.x frame, this object normally
contains a MAC address. For interfaces which do not have such
an address (e.g., a serial line), this object should contain
an octet string of zero length."
::= { panaNotificationVariables 2 }
panaNewPacNotification NOTIFICATION-TYPE
OBJECTS {
spdActionExecuted,
spdIPEndpointAddType,
spdIPEndpointAddress,
spdIPSourceType,
spdIPSourceAddress,
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spdIPDestinationType,
spdIPDestinationAddress,
panaEpIfIndex,
panaL2SourceAddress}
STATUS current
DESCRIPTION
"Notification that EP detected traffic coming from an
unauthorized source. When source and destination IP addresses
of the traffic is unknown, spdIPSourceType and
spdIPDestinationType must be zero. When source L2 address of
the traffic is unknown, panaL2SourceAddress must be zero.Notification
that EP detected traffic coming from an
unauthorized source."
::= { panaNotifications 1 }
--
--
-- Conformance information
--
--
panaGroups OBJECT IDENTIFIER
::= { panaConformanceObjects 1 }
panaCompliances OBJECT IDENTIFIER
::= { panaConformanceObjects 2 }
--
-- Compliance Groups Definitions
--
panaL2FilterGroup OBJECT-GROUP
OBJECTS {
panaL2FiltEpIfIndex,
panaL2FiltAddr,
panaL2FiltPmk,
panaL2FiltPmkName,
panaL2FiltPmkLifetime,
panaL2FiltLastChanged,
panaL2FiltStorageType,
panaL2FiltRowStatus }
STATUS current
DESCRIPTION
"The Link-layer Filter Group."
::= { panaGroups 1 }
panaNewPacNotificationObjectsGroup OBJECT-GROUP
OBJECTS {
panaEpIfIndex,
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panaL2SourceAddress }
STATUS current
DESCRIPTION
"PaC Presence Notification Objects Group."
::= { panaGroups 2 }
panaNewPacNotificationGroup NOTIFICATION-GROUP
NOTIFICATIONS {
panaNewPacNotification}
STATUS current
DESCRIPTION
"PaC Presence Notification Group."
::= { panaGroups 3 }
--
-- Compliance statements
--
panaFilterCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP entities that support
PANA DI-based filtering."
MODULE -- This Module
MANDATORY-GROUPS { panaL2FilterGroup }
OBJECT panaL2FiltRowStatus
SYNTAX RowStatus { active(1), createAndGo(4), destroy(6) }
DESCRIPTION
"Support of the values notInService(2), notReady(3),
and createAndWait(5) is not required."
OBJECT panaL2FiltLastChanged
MIN-ACCESS not-accessible
DESCRIPTION
"This object not required for compliance."
MODULE IPSEC-SPD-MIB
MANDATORY-GROUPS {
spdEndpointGroup,
spdGroupContentsGroup,
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spdRuleDefinitionGroup,
spdStaticFilterGroup,
spdStaticActionGroup }
OBJECT spdEndGroupRowStatus
SYNTAX RowStatus { active(1), createAndGo(4), destroy(6) }
DESCRIPTION
"Support of the values notInService(2), notReady(3),
and createAndWait(5) is not required."
OBJECT spdEndGroupLastChanged
MIN-ACCESS not-accessible
DESCRIPTION
"This object not required for compliance."
OBJECT spdGroupContComponentType
SYNTAX INTEGER { rule(2) }
DESCRIPTION
"Support of the value group(1) is only required for
implementations which support Policy Groups within
Policy Groups."
OBJECT spdGroupContRowStatus
SYNTAX RowStatus { active(1), createAndGo(4), destroy(6) }
DESCRIPTION
"Support of the values notInService(2), notReady(3),
and createAndWait(5) is not required."
OBJECT spdGroupContLastChanged
MIN-ACCESS not-accessible
DESCRIPTION
"This object not required for compliance."
OBJECT spdRuleDefRowStatus
SYNTAX RowStatus { active(1), createAndGo(4), destroy(6) }
DESCRIPTION
"Support of the values notInService(2), notReady(3),
and createAndWait(5) is not required."
OBJECT spdRuleDefLastChanged
MIN-ACCESS not-accessible
DESCRIPTION
"This object not required for compliance."
::= { panaCompliances 1 }
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panaNewPacNotificationCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP entities that support
new PaC presence Notification."
MODULE -- This Module
MANDATORY-GROUPS {
panaNewPacNotificationObjectsGroup,
panaNewPacNotificationGroup
}
MODULE IPSEC-SPD-MIB
MANDATORY-GROUPS { spdActionLoggingObjectGroup }
::= { panaCompliances 2 }
END
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7. Applicability of RTFM Meter MIB
RTFM provides for the measurement of network traffic flows:
o a method of specifying traffic flows within a network
o a hierarchy of devices (meters, meter readers, managers) for
measuring the specified flows
o a mechanism for configuring meters and meter readers, and for
collecting the flow data from remote meters
RTFM provides high time resolution for flow first- and last-packet
times. Counters for long-duration flows may be read at intervals
determined by a manager. The RTFM Meter is designed so as to do as
much data reduction work as possible, which minimizes the amount of
data to be read and the amount of processing needed to produce useful
reports from it.
RTFM flow data can be used for a wide range of purposes, such as
usage accounting, long-term recording of network usage (classified by
IP address attributes) and real-time analysis of traffic flows at
remote metering points.
PANA recommends the use of the following RTFM module and architecture
for the PAA to collect accounting information from the EP(s). It is
the responsability of the PAA to organise the correlation between the
EP filters, RTFM flows, the PANA and the AAA sessions.
RTFM Meter MIB [RFC2720] describes the SNMP Management Information
Base for an RTFM meter, including its flow table, rule table (storing
the meter's rulesets) and the control tables used for managing a
meter and reading flow data from it.
[RFC2722] defines the RTFM Architecture, giving descriptions of each
component. Explains how traffic flows are viewed as logical entities
described in terms of their address-attribute values, so that each is
defined by the attributes of its end-points. Gives a detailed
description of the RTFM traffic meter, with full details of how flows
are stored in the meter's flow table, and how packets are matched in
accordance with rules stored in a ruleset.
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8. EP Configuration Example
Below are usage examples of the MIB modules in the PANA context.
8.1. Common setup
The "EndPoint to Group" table is used to map policy (groupings) onto
an endpoint (EP-ADDR is the IP address) where traffic is to pass by.
Any policy group assigned to an endpoint is then used to control
access to the traffic passing by it.
So far, we define below two policy groups at the EP interface ("EP-
SPD-IN" and "EP-SPD-OUT").
spdEndpointToGroupTable, row 1:
o spdEndGroupDirection = incoming;
o spdEndGroupIdentType = IPv4;
o spdEndGroupAddress = EP-ADDR;
o spdEndGroupName = "EP-SPD-IN";
spdEndpointToGroupTable, row 2:
o spdEndGroupDirection = outgoing;
o spdEndGroupIdentType = IPv4;
o spdEndGroupAddress = EP-ADDR;
o spdEndGroupName = "EP-SPD-OUT";
Within each of the policy group defined above, we define a sub-group
(a compound filter) dedicated to the treatment of traffic that is
allowed prior to any configuration. The following configuration
illustrates the incoming allowed unprotected traffic:
spdGroupContentsTable, row 1:
o spdGroupContName = "EP-SPD-IN";
o spdGroupContPriority = '10';
o spdGroupContFilter = spdTrueFilterInstance;
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o spdGroupContComponentType = group;
o spdGroupContComponentName = "EP-ALLOWED-UNPROTECTED-IN";
Within this sub-group, we define a rule (a sub-filter) dedicated to
each allowed traffic types (namely PANA, ARP, IPv6 Neighbor
Discovery, DHCP, etc). The following configuration illustrates the
case of incoming DHCP traffic:
spdGroupContentsTable, row 2:
o spdGroupContName = "EP-ALLOWED-UNPROTECTED-IN";
o spdGroupContPriority = '1';
o spdGroupContFilter = diffServMultiFieldClfrTable.10;
o spdGroupContComponentType = rule;
o spdGroupContComponentName = "EP-DHCP-ACCEPT-IN";
We define the corresponding filter in the DiffServ Multi-Field
Classifier table (DIFFSERV_MIB, [RFC3289]), which matches the DHCP
packets:
diffServMultiFieldClfrTable, row 10:
o diffServMultiFieldClfrAddrType = v4;
o diffServMultiFieldClfrSrcL4PortMin = '546' (DHCP);
o diffServMultiFieldClfrSrcL4PortMax = '547' (DHCP);
o diffServMultiFieldClfrProtocol = '17' (UDP);
The "Rule Defininition" table links a rule with a given action in the
SPD action MIB. E.g. the following entries links the filter defined
above with the "accept" action statically defined in the SPD MIB
(spdStaticActions.3).
spdRuleDefinitionTable, row 1:
o spdRuleDefName = "EP-DHCP-ACCEPT-IN";
o spdRuleDefDescription = "Allow Incoming DHCP packets";
o spdRuleDefFilter = spdTrueFilterInstance;
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o spdRuleDefFilterNegated = false (default);
o spdRuleDefAction = spdAcceptAction;
8.2. General IP-based Access Control
In this section, we need to configure the SPD so that EP accepts IP
packets coming from/going to the client 'PaC1'. In the whole
section, 'PaC1-IP@' is the IP address of 'PaC1'.
Within the incoming policy group defined above ("EP-SPD-IN"), we
define a rule dedicated to the treatment of packets coming from
"PaC1" and the EP we are provisioning.
spdGroupContentsTable, row 3:
o spdGroupContName = "EP-SPD-IN";
o spdGroupContPriority = '100';
o spdGroupContFilter = diffServMultiFieldClfrTable.1;
o spdGroupContComponentType = rule;
o spdGroupContComponentName = "EP-PaC1-ACCEPT-IN";
We define the filter in the DiffServ Multi-field Classifier table,
which matches IP packets coming from the PaC:
diffServMultiFieldClfrTable, row 1:
o diffServMultiFieldClfrAddrType = v4;
o diffServMultiFieldClfrSrcAddr = 'PaC1-IP@';
diffServMultiFieldClfrTable, row 2:
o diffServMultiFieldClfrAddrType = v4;
o diffServMultiFieldClfrDstAddr = 'PaC1-IP@';
The following entries links the two filters defined above with the
"accept" action.
spdRuleDefinitionTable, row 2:
o spdRuleDefName = "EP-PaC1-ACCEPT-IN";
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o spdRuleDefDescription = "Allow Incoming IP packets from PaC1";
o spdRuleDefFilter = spdTrueFilterInstance;
o spdRuleDefFilterNegated = false (default);
o spdRuleDefAction = spdAcceptAction;
spdRuleDefinitionTable, row 3:
o spdRuleDefName = "EP-PaC1-ACCEPT-OUT";
o spdRuleDefDescription = "Allow Outgoing IP packets to PaC1";
o spdRuleDefFilter = spdTrueFilterInstance;
o spdRuleDefFilterNegated = false (default);
o spdRuleDefAction = spdAcceptAction;
The same thing must be done for the outgoing direction and this
results in a policy such that any packet coming from/going to the PaC
is allowed to go through the EP (via EP-ADDR endpoint).
8.3. IPsec-based Access Control
In this section we consider the case when IPsec is used to control
access at the IP level. In order to avoid many redundancies, the
previous configuration set is still valid. See below a usage example
of IKEACTION-MIB and IPSECACTION-MIB.
-- IKE Phase 1 configuration (agressive mode):
We define a first-level filter in policy group "EP-SPD-IN" of the SPD
MIB, using the "Group contents" table. This filter isolates IKE
phase 1 traffic coming to the EP on this interface:
spdGroupContentsTable, row 4:
o spdGroupContName = "EP-SPD-IN";
o spdGroupContPriority = '1';
o spdGroupContFilter = ipiaIkePhase1Filter;
o spdGroupContComponentType = group;
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o spdGroupContComponentName = "EP-IKE1-IN";
Within this IKE-specific policy sub-group, we specify a second-level
filter to apply for for the traffic coming from PaC1.
spdGroupContentsTable, row 5:
o spdGroupContName = "EP-IKE-Phase1-IN";
o spdGroupContPriority = '1';
o spdGroupContFilter = diffServMultiFieldClfrTable.1;
o spdGroupContComponentType = group;
o spdGroupContComponentName = "EP-IKE1-PaC1-IN";
The diffServMultiFieldClfrTable.1 entry has been defined in the
previous section. Within the lattest sub-group we finally specify
the rule to apply for the IKE traffic coming from PaC1 and matching
the right identity (id_key_id).
spdGroupContentsTable, row 6:
o spdGroupContName = "EP-IKE1-PaC1-IN";
o spdGroupContPriority = '1';
o spdGroupContFilter = ipiaPeerIdentityFilterTable.1;
o spdGroupContComponentType = rule;
o spdGroupContComponentName = "PaC1-IKE1-RULE";
The "Peer Identity Filter" table specifically informs the EP on the
value of the idKeyId to use in IKE messages:
ipiaPeerIdentityFilterTable, row 1:
o ipiaPeerIdFiltName = "PaC1-IKE1-ID-FILTER";
o ipiaPeerIdFiltIdentityType = id_Key_Id;
o ipiaPeerIdFiltIdentityValue = 'PANA-Session-Id|PANA-Key-Id';
The "Rule Defininition" table links a rule with a given action in the
IKE action MIB. This action will be triggered upon reception at the
EP of an IKE phase 1 packet coming from PaC1 and matching the right
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id_key_id.
spdRuleDefinitionTable, row 4:
o spdRuleDefName = "PaC1-IKE-RULE";
o spdRuleDefDescription = "IPsec Access Control for PaC1";
o spdRuleDefFilter = spdTrueFilterInstance;
o spdRuleDefFilterNegated = false (default);
o spdRuleDefAction = ipiaIkeActionTable.1;
The spdRuleDefAction attribute in the entry above points to a row in
the ipiaIkeActionTable, defined below:
ipiaIkeActionTable, row 1:
o ipiaIkeActName = "PaC1-IKE";
o ipiaIkeActParametersName = "SA1-PaC1";
o ipiaIkeActThresholdDerivedKeys = '100' (default);
o ipiaIkeActExchangeMode = aggressive;
o ipiaIkeActAgressiveModeGroupId = 'xxx' (Diffie-Hellman values);
o ipiaIkeActIdentityType = id_Key_Id;
o ipiaIkeActIdentityContext = "PANA";
o ipiaIkeActPeerName = "PaC1";
The following entry links together the "PaC1" identity with the
corresponding credentials table entry:
ipiaIkeIdentityTable, row 1:
o spdEndGroupIdentType = IPv4;
o spdEndGroupAddress = 'EP-ADDR';
o ipiaIkeActIdentityType = id_Key_Id;
o ipiaIkeActIdentityContext = 'PANA';
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o ipiaIkeIdCredentialName = "PaC1-PSK";
Finally, the pre-shared key derivated at the PAA is set in the IPSA
Credentials table (IPSECACTION-MIB):
ipsaCredentialTable, row 1:
o ipsaCredName = "PaC1-PSK";
o ipsaCredType = sharedSecret;
o ipsaCredCredential = 'PSK-derived-at-the-PAA';
o ipsaCredSize = 'xxx';
o ipsaMgnName = "xxx";
o ipsaRemoteID = 'PaC1';
The Ike Action entry (above) is indexed by a name (ipiaIkeActName
attribute), which is used as the primary index into the
ipiaIkeActionProposalsTable. The secondary index is a priority,
which allows ordering of the proposals that will be sent to the peer
(or accepted from the peer).
ipiaIkeActionProposalsTable, row 1:
o ipiaIkeActPropName = "PaC1-IKE-PROP1";
o ipiaIkeActPropPriority = '1';
The ipiaIkeActPropName points to a row in the ipiaIkeProposalsTable,
which contains the actual IKE parameters for the Phase 1 exchanges:
ipiaIkeProposalsTable, row 1:
o ipiaIkeActPropName = "PaC1-IKE-PROP1";
o ipiaIkePropLifetimeDerivedKeys = xxx;
o ipiaIkePropCipherAlgorithm = 3DES;
o ipiaIkePropCipherKeyLength = xxx;
o ipiaIkePropHashAlgorithm = HMAC-SHA1;
o ipiaIkePropPrfAlgorithm = xxx;
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o ipiaIkePropVendorId = xxx;
o ipiaIkePropDhGroup = 2;
o ipiaIkePropAuthenticationMethod = xxx;
o ipiaIkePropMaxLifetimeSecs = xxx;
o ipiaIkePropMaxLifetimeKB = xxx;
There is a similar hierarchy for the proposals, which are used for
Phase 2 negotiations, and result in a Phase 2 SA being created, upon
successful negotiations. The parameters would be set up in the
ipiaIpsecActionTable, ipiaIpsecProposalsTable and
ipiaIpsecTransformsTable, along with the necessary related tables.
One would then need a rule to trigger the row in the
ipiaIpsecActionTable. See for further details on the IPSP MIBs
usage.
8.4. Link-layer Access control
The section below gives a usage example of the PANA module in the
general L2-based access control case.
The example below assumes the configuration set detailed in
Section 8.1 is valid. Here we need to configure the SPD so that EP
accepts accepts 802 packets coming from/going to the client 'PaC1'?
In the whole section 'PaC1-MAC@' is the MAC address of 'PaC1'.
Within the incoming policy group defined above ("EP-SPD-IN"), we
define a rule dedicated to the treatment of packets coming from
"PaC1" and the EP we are provisioning.
spdGroupContentsTable, row 3:
o spdGroupContName = "EP-SPD-IN";
o spdGroupContPriority = '101';
o spdGroupContFilter = panaL2FilterTable.1;
o spdGroupContComponentType = rule;
o spdGroupContComponentName = "EP-PaC1-ACCEPT-IN-L2";
We define the filter in the Link-layer filter table, which matches L2
packets coming from the PaC to interface #5, which a 802.11
interface:
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panaL2FilterTable, row 1:
o panaL2FiltEpIfIndex = 5;
o panaL2FiltAddr = "00-11-0A-80-4A-58";
o panaL2FiltPmk = "...";
o panaL2FiltPmkName = "...";
o panaL2FiltPmkLifetime = 10800;
The following entries links the filter defined above with the
"accept" action.
spdRuleDefinitionTable, row 20:
o spdRuleDefName = "EP-PaC1-ACCEPT-IN-L2";
o spdRuleDefDescription = "Allow Incoming L2 packets from PaC1 via
Interface #5";
o spdRuleDefFilter = spdTrueFilterInstance;
o spdRuleDefFilterNegated = false (default);
o spdRuleDefAction = spdAcceptAction;
The same thing must be done for the outgoing direction and this
results in a policy such that any packet coming from/going to the PaC
is allowed to go through the EP.
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9. Security Considerations
The MIB defined in the present document relates to a system which
will provide network access. As such, improper manipulation of the
objects represented by this MIB may result in denial of service to a
large number of end-users. In addition, manipulation of the
panaL2FilterTable and diffServMultiFieldClfrTable may allow an end-
user to gain network access, spoof their IP addresses, change the
authorized device identifiers, or affect other end-users in either a
positive or negative manner.
There are a number of management objects defined in this MIB module
with a MAX-ACCESS clause of read-write and/or read-create. Such
objects may be considered sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
network operations. These are the tables and objects and their
sensitivity/vulnerability:
o The use of panaL2FilterTable to specify which Link-layer addresses
are authorized to access the network on which interface is
considered to be only limited protection and does not protect
against attacks which spoof the management station's IP address.
The use of SNMPv3 security is mandated. Specifically, SNMPv3 VACM
and USM MUST be used with any v3 agent which implements this MIB.
As described in Section 2.1, it is assumed that PAA and EP are pre-
configured to be able to communicate each other with a required
security association. The pre-configured SNMP user passphrase for
the security association between PAA and EP should not be used for a
long term and should be updated at a reasonable frequency.
It might be sufficient to use the same SNMP user identity and
passphrase for all EPs controlled by the same PAA (the same thing can
apply even when the EPs are controlled by multiple PAAs.) Note that
even if the same SNMP user identity and passphrase for all EPs are
used, the different SNMP authentication and encryption keys are
derived for each EP, because the combination of SNMP user identity
and engine-id is used for deriving the keys.
SNMP versions prior to SNMPv3 did not include adequate security.
Even if the network itself is secure (for example by using IPsec),
even then, there is no control as to who on the secure network is
allowed to access and GET/SET (read/change/create/delete) the objects
in this MIB module.
It is RECOMMENDED that implementers consider the security features as
provided by the SNMPv3 framework (see [RFC3410], section 8),
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including full support for the SNMPv3 cryptographic mechanisms (for
authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT
RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to
enable cryptographic security. It is then a customer/operator
responsibility to ensure that the SNMP entity giving access to an
instance of this MIB module is properly configured to give access to
the objects only to those principals (users) that have legitimate
rights to indeed GET or SET (change/create/delete) them.
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10. IANA Considerations
The only IANA considerations for this document is the node number
allocation of the PANA-EP-MIB itself.
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11. Acknowledgements
The authors would like to thank David Perkins for the MIB deep
inspection and Robert Story, who provided very helpful
recommendations on the IPSP MIBs usage.
This document originaly leverages on similar works done in the MIDCOM
working group. Thanks to the authors of those IDs. Thanks to Thomas
Moore and Olivier Marce for their grateful help during the edition of
this document.
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12. References
12.1. Normative References
[I-D.ietf-pana-pana]
Forsberg, D., "Protocol for Carrying Authentication for
Network Access (PANA)", draft-ietf-pana-pana-11 (work in
progress), March 2006.
[I-D.ietf-pana-ipsec]
Parthasarathy, M., "PANA Enabling IPsec based Access
Control", draft-ietf-pana-ipsec-07 (work in progress),
July 2005.
[I-D.ietf-ipsp-spd-mib]
Hardaker, W., "IPsec Security Policy Database
Configuration MIB", draft-ietf-ipsp-spd-mib-06 (work in
progress), April 2006.
[I-D.ietf-ipsp-ikeaction-mib]
Hardaker, W., "IPsec Security Policy IKE Action MIB",
draft-ietf-ipsp-ikeaction-mib-01 (work in progress),
August 2005.
[I-D.ietf-ipsp-ipsecaction-mib]
Hardaker, W., "IPsec Security Policy IPsec Action MIB",
draft-ietf-ipsp-ipsecaction-mib-01 (work in progress),
August 2005.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Textual Conventions for SMIv2",
STD 58, RFC 2579, April 1999.
[RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder,
"Conformance Statements for SMIv2", STD 58, RFC 2580,
April 1999.
[RFC3289] Baker, F., Chan, K., and A. Smith, "Management Information
Base for the Differentiated Services Architecture",
RFC 3289, May 2002.
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12.2. Informative References
[RFC4058] Yegin, A., Ohba, Y., Penno, R., Tsirtsis, G., and C. Wang,
"Protocol for Carrying Authentication for Network Access
(PANA) Requirements", RFC 4058, May 2005.
[RFC4016] Parthasarathy, M., "Protocol for Carrying Authentication
and Network Access (PANA) Threat Analysis and Security
Requirements", RFC 4016, March 2005.
[I-D.ietf-pana-framework]
Jayaraman, P., "PANA Framework",
draft-ietf-pana-framework-06 (work in progress),
March 2006.
[RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management
Protocol (SNMPv3)", STD 62, RFC 3414, December 2002.
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction and Applicability Statements for Internet-
Standard Management Framework", RFC 3410, December 2002.
[RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing Simple Network Management
Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
December 2002.
[RFC2401] Kent, S. and R. Atkinson, "Security Architecture for the
Internet Protocol", RFC 2401, November 1998.
[RFC2409] Harkins, D. and D. Carrel, "The Internet Key Exchange
(IKE)", RFC 2409, November 1998.
[RFC3588] Calhoun, P., Loughney, J., Guttman, E., Zorn, G., and J.
Arkko, "Diameter Base Protocol", RFC 3588, September 2003.
[I-D.ietf-aaa-diameter-cc]
Mattila, L., Koskinen, J., Stura, M., Loughney, J., and H.
Hakala, "Diameter Credit-control Application",
draft-ietf-aaa-diameter-cc-06 (work in progress),
August 2004.
[I-D.ietf-eap-keying]
Aboba, B., "Extensible Authentication Protocol (EAP) Key
Management Framework", draft-ietf-eap-keying-13 (work in
progress), May 2006.
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[802.11i] IEEE P802, "Wireless MAC and PHY specifications, MAC
security enhancements", IEEE 802.11i, July 2004.
[RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet
Networks", RFC 2464, December 1998.
[RFC2720] Brownlee, N., "Traffic Flow Measurement: Meter MIB",
RFC 2720, October 1999.
[RFC2722] Brownlee, N., Mills, C., and G. Ruth, "Traffic Flow
Measurement: Architecture", RFC 2722, October 1999.
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Authors' Addresses
Yacine El Mghazli (Editor)
Alcatel
Route de Nozay
Marcoussis 91460
France
Email: yacine.el_mghazli@alcatel.fr
Yoshihiro Ohba
Toshiba America Research, Inc.
1, Telcordia Drive
Piscataway, NJ 08854
USA
Email: yohba@tari.toshiba.com
Julien Bournelle
GET/INT
9, rue Charles Fourier
Evry 91011
France
Email: julien.bournelle@int-evry.fr
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El Mghazli, et al. Expires December 25, 2006 [Page 47]
