|
Network Working Group Request for Comments: 3792 Category: Informational |
P. Nesser, II Nesser & Nesser Consulting A. Bergstrom, Ed. Ostfold University College June 2004 |
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
Copyright © The Internet Society (2004).
This document seeks to document all usage of IPv4 addresses in currently deployed IETF Security Area documented standards. In order to successfully transition from an all IPv4 Internet to an all IPv6 Internet, many interim steps will be taken. One of these steps is the evolution of current protocols that have IPv4 dependencies. It is hoped that these protocols (and their implementations) will be redesigned to be network address independent, but failing that will at least dually support IPv4 and IPv6. To this end, all Standards (Full, Draft, and Proposed) as well as Experimental RFCs will be surveyed and any dependencies will be documented.
1. Introduction
2. Document Organisation
3. Full Standards
4. Draft Standards
5. Proposed Standards
6. Experimental RFCs
7. Summary of Results
7.1. Standards
7.2. Draft Standards
7.3. Proposed Standards
7.4. Experimental RFCs
8. Security Considerations
9. Acknowledgements
10. Normative Reference
11. Authors' Addresses
12. Full Copyright Statement
This document is part of a document set aiming to document all usage of IPv4 addresses in IETF standards. In an effort to have the information in a manageable form, it has been broken into 7 documents conforming to the current IETF areas (Application, Internet, Operations and Management, Routing, Security, Sub-IP, and Transport).
For a full introduction, please see the introduction [1].
Sections 3, 4, 5, and 6 each describe the raw analysis of Full, Draft, and Proposed Standards, and Experimental RFCs. Each RFC is discussed in its turn starting with RFC 1 and ending with (around) RFC 3100. The comments for each RFC are "raw" in nature. That is, each RFC is discussed in a vacuum and problems or issues discussed do not "look ahead" to see if the problems have already been fixed.
Section 7 is an analysis of the data presented in Sections 3, 4, 5, and 6. It is here that all of the results are considered as a whole and the problems that have been resolved in later RFCs are correlated.
Full Internet Standards (most commonly simply referred to as "Standards") are fully mature protocol specification that are widely implemented and used throughout the Internet.
There are no IPv4 dependencies in this specification.
Draft Standards represent the penultimate standard level in the IETF. A protocol can only achieve draft standard when there are multiple, independent, interoperable implementations. Draft Standards are usually quite mature and widely used.
There are no IPv4 dependencies in this specification.
Section 3.2.1 The WWW-Authenticate Response Header include he following text:
(Note: including the IP address of the client in the nonce would appear to offer the server the ability to limit the reuse of the nonce to the same client that originally got it. However, that would break proxy farms, where requests from a single user often go through different proxies in the farm. Also, IP address spoofing is not that hard.)
Section 4.5 Replay Attacks contains the text:
Thus, for some purposes, it is necessary to protect against
replay attacks. A good Digest implementation can do this in
various ways. The server created "nonce" value is
implementation dependent, but if it contains a digest of the
client IP, a time-stamp, the resource ETag, and a private
server key (as recommended above) then a replay attack is not
simple. An attacker must convince the server that the request
is coming from a false IP address and must cause the server to
deliver the document to an IP address different from the
address to which it believes it is sending the document. An
attack can only succeed in the period before the time-stamp
expires. Digesting the client IP and time-stamp in the nonce
permits an implementation which does not maintain state between
transactions.
Both of these statements are IP version independent and must rely on the implementers discretion.
Section 3. Packet Format has the following notes:
Identifier
The Identifier field is one octet, and aids in matching requests and replies. The RADIUS server can detect a duplicate request if it has the same client source IP address and source UDP port and Identifier within a short span of time.
and
A RADIUS server MUST use the source IP address of the RADIUS UDP packet to decide which shared secret to use, so that RADIUS requests can be proxied.
This text is version neutral but implementers should allow for the use of both IPv4 and IPv6 addresses.
Section 5. Attributes defines a number of IP specific attributes:
4 NAS-IP-Address
8 Framed-IP-Address
9 Framed-IP-Netmask
10 Framed-Routing
14 Login-IP-Host
22 Framed-Route
and definitions for the "value" field of the following type:
address 32 bit value, most significant octet first.
The attributes are further defined as follows:
Description
This Attribute indicates the identifying IP Address of the NAS which is requesting authentication of the user, and SHOULD be unique to the NAS within the scope of the RADIUS server. NAS-IP-Address is only used in Access-Request packets. Either NAS-IP-Address or NAS-Identifier MUST be present in an Access-Request packet.
Note that NAS-IP-Address MUST NOT be used to select the shared secret used to authenticate the request. The source IP address of the Access-Request packet MUST be used to select the shared secret.
A summary of the NAS-IP-Address Attribute format is shown below. The fields are transmitted from left to right.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Address (cont) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
4 for NAS-IP-Address.
Length
6
Address
The Address field is four octets.
Description
This Attribute indicates the address to be configured for the user. It MAY be used in Access-Accept packets. It MAY be used in an Access-Request packet as a hint by the NAS to the server that it would prefer that address, but the server is not required to honor the hint.
A summary of the Framed-IP-Address Attribute format is shown below. The fields are transmitted from left to right.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Address (cont) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
8 for Framed-IP-Address.
Length
6
Address
The Address field is four octets. The value 0xFFFFFFFF indicates that the NAS Should allow the user to select an address (e.g., Negotiated). The value 0xFFFFFFFE indicates that the NAS should select an address for the user (e.g., Assigned from a pool of addresses kept by the NAS). Other valid values indicate that the NAS should use that value as the user's IP address.
Description
This Attribute indicates the IP netmask to be configured for the user when the user is a router to a network. It MAY be used in Access-Accept packets. It MAY be used in an Access- Request packet as a hint by the NAS to the server that it would prefer that netmask, but the server is not required to honor the hint.
A summary of the Framed-IP-Netmask Attribute format is shown below. The fields are transmitted from left to right.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Address (cont) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
9 for Framed-IP-Netmask.
Length
6
Address
The Address field is four octets specifying the IP netmask of the user.
Description
"This Attribute indicates the system with which to connect the user, when the Login-Service Attribute is included. It MAY be used in Access-Accept packets. It MAY be used in an Access- Request packet as a hint to the server that the NAS would prefer to use that host, but the server is not required to honor the hint."
A summary of the Login-IP-Host Attribute format is shown below. The fields are transmitted from left to right.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Address
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Address (cont) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type
14 for Login-IP-Host.
Length
6
Address
The Address field is four octets. The value 0xFFFFFFFF indicates that the NAS SHOULD allow the user to select an address. The value 0 indicates that the NAS SHOULD select a host to connect the user to. Other values indicate the address the NAS SHOULD connect the user to.
Description
This Attribute provides routing information to be configured for the user on the NAS. It is used in the Access-Accept packet and can appear multiple times.
A summary of the Framed-Route Attribute format is shown below. The fields are transmitted from left to right.
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| Type | Length | Text ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
Type
22 for Framed-Route.
Length
>= 3
Text
The Text field is one or more octets, and its contents are implementation dependent. It is intended to be human readable and MUST NOT affect operation of the protocol. It is recommended that the message contain UTF-8 encoded 10646 [7] characters.
For IP routes, it SHOULD contain a destination prefix in dotted quad form optionally followed by a slash and a decimal length specifier stating how many high order bits of the prefix to use. That is followed by a space, a gateway address in dotted quad form, a space, and one or more metrics separated by spaces. For example, "192.168.1.0/24 192.168.1.1 1 2 -1 3 400". The length specifier may be omitted, in which case it defaults to 8 bits for class A prefixes, 16 bits for class B prefixes, and 24 bits for class C prefixes. For example, "192.168.1.0 192.168.1.1 1".
Whenever the gateway address is specified as "0.0.0.0" the IP address of the user SHOULD be used as the gateway address.
There are also several example authentication sequences that use the attributes discussed above and hence have IPv4 addresses.
Although the definitions in this RFC are limited to IPv4 addresses, the specification is easily extensible for new attribute types. It is therefore relatively simple to create new IPv6 specific attributes.
Proposed Standards are introductory level documents. There are no requirements for even a single implementation. In many cases Proposed are never implemented or advanced in the IETF standards process. They therefore are often just proposed ideas that are
presented to the Internet community. Sometimes flaws are exposed or they are one of many competing solutions to problems. In these later cases, no discussion is presented as it would not serve the purpose of this discussion.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
Although this specification specifies optional use of host addresses, there are no specific requirements that the addresses be IPv4. The specification has no IPv4 dependencies, but implementations might have issues.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification. The operations described operate on the entire IP packet without specifying that the IP packet be IPv4 or IPv6.
There are no IPv4 dependencies in this specification. The operations described operate on the entire IP packet without specifying that the IP packet be IPv4 or IPv6.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification is IPv6 aware and will function normally on either IPv4 and IPv6.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This RFC documents a security mechanism for an IPv4 only routing specification. It is expected that a similar (or better) mechanism will be developed for RIPng.
This document defines an IP version independent specification and has no IPv4 dependencies.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
Although the specification enhancements have no IPv4 dependencies, it is an update to an IPv4 only routing specification.
This specification is both IPv4 and IPv6 aware.
This specification is both IPv4 and IPv6 aware.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification is both IPv4 and IPv6 aware.
This specification is both IPv4 and IPv6 aware.
This specification is both IPv4 and IPv6 aware.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification. There are discussions of A and AAAA records in the document, but have no real implications on IPv4 dependency or on any IP related address records.
There are no IPv4 dependencies in this specification.
Section 3.1 X.509 CERT RR Names
Some X.509 versions permit multiple names to be associated with subjects and issuers under "Subject Alternate Name" and "Issuer Alternate Name". For example, x.509v3 has such Alternate Names with an ASN.1 specification as follows:
GeneralName ::= CHOICE {
otherName [0] INSTANCE OF OTHER-NAME,
rfc822Name [1] IA5String,
dNSName [2] IA5String,
x400Address [3] EXPLICIT OR-ADDRESS.&Type,
directoryName [4] EXPLICIT Name,
ediPartyName [5] EDIPartyName,
uniformResourceIdentifier [6] IA5String,
iPAddress [7] OCTET STRING,
registeredID [8] OBJECT IDENTIFIER
}
uses a potential IPv4 only address. It goes on with the following example:
Example 2: Assume that an X.509v3 certificate is issued to
/CN=James Hacker/L=Basingstoke/O=Widget Inc/C=GB/ with Subject
Alternate names of (a) domain name widget.foo.example,
(b) IPv4 address 10.251.13.201, and (c) string "James Hacker
<hacker@mail.widget.foo.example>". Then the storage locations
recommended, in priority order, would be
(1) widget.foo.example,
(2) 201.13.251.10.in-addr.arpa, and
(3) hacker.mail.widget.foo.example.
Since the definition of X.509v3 certificates is not discussed in this document it is unclear if IPv6 addresses are also supported in the above mentioned field. The document does however refer to RFC 2459 for the definition of a certificate, and RFC 2459 is IPv6 and IPv4 aware -- so it seems this specification is IPv4 and IPv6 aware.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification is both IPv4 and IPv6 aware and needs no changes.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
The document uses the InetAddress variable which does not necessarily limit it to IPv4 addresses so there are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This document is specifically designed for IPv4.
There are no IPv4 dependencies in this specification.
This is an IPv6 related document and is not discussed in this document.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This document is only designated for IPv4. It is expected that similar functionality is available in DHCPv6.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification is IPv4 and IPv6 aware.
There are no IPv4 dependencies in this specification.
Experimental RFCs typically define protocols that do not have
widescale implementation or usage on the Internet. They are often
propriety in nature or used in limited arenas. They are documented
to the Internet community in order to allow potential
interoperability or some other potential useful scenario. In a few
cases they are presented as alternatives to the mainstream solution
to an acknowledged problem.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification assumes the use of IGMP and is therefore limited to IPv4 multicast. It is assumed that a similar mechanism may be defined for IPv6 multicasting.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This OSPF option is IPv4 limited. See the following packet format:
A router public key certificate is a package of data signed by a Trusted Entity. This certificate is included in the router PKLSA and in the router configuration information. To change any of the values in the certificate, a new certificate must be obtained from a TE.
1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Router Id |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| TE Id | TE Key Id | Rtr Key Id | Sig Alg |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Create Time |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Key Field Length | Router Role | #Net Ranges |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| IP Address |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Address Mask |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| IP Address/Address Mask for each Net Range ... /
| ... /
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Router Public Key |
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
| Certification /
+-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+
#NET RANGES The number of network ranges that follow. A
network range is defined to be an IP Address
and an Address Mask. This list of ranges
defines the addresses that the Router is
permitted to advertise in its Router Links LSA.
Valid values are 0-255. If there are 0 ranges
the router cannot advertise anything. This is
not generally useful. One range with address=0
and mask=0 will allow a router to advertise any
address.
IP ADDRESS & ADDRESS MASK Define a range of addresses that this router may advertise. Each is a 32 bit value. One range with address=0 and mask=0 will allow a router to advertise any address.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
There are no IPv4 dependencies in this specification.
This specification is both IPv4 and IPv6 aware and needs no changes.
There are no IPv4 dependencies in this specification.
In the initial survey of RFCs 4 positives were identified out of a total of 124, broken down as follows:
Standards: 0 out of 1 or 0.00%
Draft Standards: 1 out of 3 or 33.33%
Proposed Standards: 1 out of 102 or 0.98%
Experimental RFCs: 2 out of 18 or 11.11%
Of those identified many require no action because they document outdated and unused protocols, while others are document protocols that are actively being updated by the appropriate working groups.
Additionally there are many instances of standards that should be updated but do not cause any operational impact if they are not updated. The remaining instances are documented below.
The problems have been resolved in RFC 3162, RADIUS and IPv6.
This functionality has been assumed by the use of the IPsec AH header as defined in RFC 2402, IP Authentication Header.
The problems are not being addressed and similar functions may be needed in Mobile IPv6.
This problem has been fixed in RFC 3315, Dynamic Host
Configuration Protocol for IPv6 (DHCPv6).
This specification relies on IPv4 IGMP Multicast and a new specification may be produced; however, the SMKD is not believed to be in use.
This specification is IPv4-only, and relies on an IPv4-only routing protocol, OSPFv2. Due to increased focus on routing security, this specification may need to be revisited, and in that case it should support both OSPFv2 and OPSFv3.
This memo examines the IPv6-readiness of specifications; this does not have security considerations in itself.
The authors would like to acknowledge the support of the Internet
Society in the research and production of this document.
Additionally the author, Philip J. Nesser II, would like to thanks
his partner in all ways, Wendy M. Nesser.
The editor, Andreas Bergstrom, would like to thank Pekka Savola for guidance and collection of comments for the editing of this document.
[1] Nesser, II, P. and A. Bergstrom, Editor, "Introduction to the Survey of IPv4 Addresses in Currently Deployed IETF Standards", RFC 3789, June 2004.
Please contact the author with any questions, comments or suggestions at:
Philip J. Nesser II
Principal
Nesser & Nesser Consulting
13501 100th Ave NE, #5202
Kirkland, WA 98034
Phone: +1 425 481 4303
Fax: +1 425 48 EMail: phil@nesser.com
Andreas Bergstrom (Editor)
Ostfold University College
Rute 503 Buer
N-1766 Halden
Norway
EMail: andreas.bergstrom@hiof.no
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