Host Identity Protocol M. Komu
Internet-Draft Helsinki Institute for Information
Intended status: Experimental Technology
Expires: November 23, 2009 Henderson
The Boeing Company
May 22, 2009
Basic Socket Interface Extensions for Host Identity Protocol (HIP)
draft-ietf-hip-native-api-06
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Abstract
This document defines extensions to the current sockets API for Host
Identity Protocol (HIP). The extensions focus on the use of public-
key based identifiers discovered via DNS resolution, but define also
interfaces for manual bindings between HITs and locators. With the
extensions, the application can also support more relaxed security
models where the communication can be non-HIP based, according to
local policies. The extensions in document are experimental and
provide basic tools for futher experimentation with policies.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. API Overview . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Interaction with the Resolver . . . . . . . . . . . . . . 5
3.2. Interaction without a Resolver . . . . . . . . . . . . . . 5
4. API Syntax and Semantics . . . . . . . . . . . . . . . . . . . 6
4.1. Socket Family and Address Structure Extensions . . . . . . 6
4.2. Extensions to Resolver Data Structures . . . . . . . . . . 8
4.2.1. Resolver Usage . . . . . . . . . . . . . . . . . . . . 9
4.3. The Use of getsockname and getpeername Functions . . . . . 10
4.4. Validating HITs . . . . . . . . . . . . . . . . . . . . . 10
4.5. Source HIT Selection by the System . . . . . . . . . . . . 11
4.6. Explicit Handling of Locators . . . . . . . . . . . . . . 12
5. Summary of New Definitions . . . . . . . . . . . . . . . . . . 14
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 15
10. Normative References . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
This document defines C-based sockets Application Programming
Interface (API) extensions for handling HIP-based identifiers
explicitly in HIP-aware applications. It is up to the applications,
or high-level programming languages or libraries, to manage the
identifiers. The extensions in this document are mainly related to
the use case in which a DNS resolution step has occurred prior to the
creation of a new socket, and assumes that the system has cached or
is otherwise able to resolve identifiers to locators (IP addresses).
The DNS extensions for HIP are described in [RFC5205]. The
extensions also cover the case in which an application may want to
explicitly provide suggested locators with the identifiers, including
supporting the opportunistic case in which the system does not know
the peer host identity.
The Host Identity Protocol (HIP) [RFC4423] proposes a new
cryptographic namespace by separating the roles of end-point
identifiers and locators by introducing a new namespace to the TCP/IP
stack. SHIM6 [I-D.ietf-shim6-proto] is another protocol based on
identity-locator split. Note that the APIs specified in this
document are specific to HIP. However, the APIs here have been
designed as much as possible so as not to preclude its use with other
protocols. The use of these APIs with other protocols is,
nevertheless, for further study.
Applications can observe the HIP layer and its identifiers in the
networking stacks with varying degrees of visibility. [RFC5338]
discusses the lowest levels of visibility in which applications are
completely unaware of the underlying HIP layer. Such HIP-unaware
applications in some circumstances use HIP-based identifiers, such as
LSIs or HITs, instead of IPv4 or IPv6 addresses and cannot observe
the identifier-locator bindings.
This document specifies extensions to [RFC3493] to define a new
socket address family, AF_HIP. The macro AF_HIP is used as an alias
for PF_HIP in this document because the distinction between AF and PF
has been lost in practice. The extensions also describe a new socket
address structure for sockets using Host Identity Tags (HITs)
explicitly and describe how the socket calls in [RFC3493] are adapted
or extended as a result.
Some applications may accept incoming communications from any
identifier. Other applications may initiate outgoing communications
without the knowledge of the peer identifier in Opportunistic Mode
[RFC5201] by just relying on a peer locator. This document describes
how to address both situations using "wildcards" as described later
in this document.
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There are two related API documents. Multihoming and explicit
locator-handling related APIs are defined in
[I-D.ietf-shim6-multihome-shim-api]. IPsec related policy attributes
and channel bindings APIs are defined in [I-D.ietf-btns-c-api]. Most
of the extensions defined in this document can be used independently
of the two mentioned related API documents.
The identity-locator split introduced by HIP introduces some policy
related challenges with datagram oriented sockets, opportunistic
mode, and manual bindings between HITs and locators. The extensions
in this document are of experimental nature and provide basic tools
for experimenting with policies. Policy related issues are left for
further experimentation.
To recap, the extensions in this document have three goals. The
first goal is to allow HIP-aware applications to open sockets to
other hosts based on the HITs alone, presuming that the underlying
system can resolve the HITs to addresses used for initial contact.
The second goal is that applications can explicitly initiate
communications with unknown peer identifiers. The third goal is to
define how HIP-aware applications may provide suggested initial
contact addresses along with the HITs.
2. Terminology
The terms used in this document are summarized in Table 1.
+---------+---------------------------------------------------------+
| Term | Explanation |
+---------+---------------------------------------------------------+
| HIP | Host Identity Protocol |
| HIT | Host Identity Tag, a 100-bit hash of a public key with |
| | a 28 bit prefix |
| LSI | Local Scope Identifier, a local, 32-bit descriptor for |
| | a given public key. |
| Locator | Routable IPv4 or IPv6 address used at the lower layers |
+---------+---------------------------------------------------------+
Table 1
3. API Overview
This section provides an overview of how the API can be used. First,
the case in which a resolver is involved in name resolution is
described, and then the case in which no resolver is involved is
described.
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3.1. Interaction with the Resolver
Before an application can establish network communications with the
entity named by a given FQDN or relative host name, the application
must translate the name into the corresponding identifier(s). DNS-
based hostname-to-identifier translation is illustrated in Figure 1.
The application calls the resolver in step a to resolve an FQDN step
b. The DNS server responds with a list of HITs and a set of locators
step c. Optionally in step d, the resolver caches the HIT to locator
mapping to the HIP module. The resolver returns the HITs to the
application step e. Finally, the application selects one HIT and
uses it in a socket call such as connect() in step f.
+----------+
| |
| DNS |
| |
+----------+
^ |
b. <FQDN> | | c. <HITs+locators
| v = HITs+locs>
+-------------+ a. getaddrinfo(<FQDN>) +----------+
| |------------------------>| |
| Application | | Resolver |
| |<------------------------| |
+-------------+ e. <HITs> +----------+
| |
| |
| f. connect(<HIT>) | d. <HITs+locs>
v v
+----------+ +----------+
| | | |
| TCP/IP | | HIP |
| Stack | | |
+----------+ +----------+
Figure 1
In practice, the resolver functionality can be implemented in
different ways. For example, it may be implemented in existing
resolver libraries or as a DNS proxy.
3.2. Interaction without a Resolver
The extensions in this document focus on the use of the resolver to
map host names to HITs and locators in HIP-aware applications. The
resolver associates implicitly the HIT with the locator(s) by e.g.
communicating the HIT-to-IP mapping to the HIP daemon. However, it
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is possible that an application operates directly on a peer HIT
without interacting with the resolver. In such a case, the
application may resort to the system to map the peer HIT to an IP
address. Alternatively, the application can explicitly map the HIT
to an IP address using socket options as specified in
[I-D.ietf-shim6-multihome-shim-api]. Full support for all of the
extensions defined in this draft requires shim socket options to be
implemented by the system.
4. API Syntax and Semantics
In this section, we describe the native HIP APIs using the syntax of
the C programming language. We limit the description to the
interfaces and data structures that are either modified or completely
new, because the native HIP APIs are otherwise identical to the
sockets API [POSIX].
4.1. Socket Family and Address Structure Extensions
The sockets API extensions define a new protocol family, PF_HIP, and
a new address family, AF_HIP. The AF_HIP and PF_HIP are aliases to
each other. These definition shall be defined as a result of
including <sys/socket.h>.
The use of the PF_HIP constant is mandatory with the socket()
function when an application uses the native HIP APIs. The
application gives the PF_HIP constant as the first argument (domain)
to the socket() function. The system returns a positive integer
representing a socket descriptor when the system supports HIP.
Otherwise, the system returns -1 and sets errno to EAFNOSUPPORT.
Figure 2 shows socket address structure for HIP.
#include <netinet/in.h>
typedef struct in6_addr hip_hit_t;
struct sockaddr_hip {
sa_family_t ship_family;
in_port_t ship_port;
uint32_t ship_pad;
uint64_t ship_flags;
hip_hit_t ship_hit;
uint8_t ship_reserved[16];
};
Figure 2
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Figure 2 is in in 4.3BSD format. The family of the socket,
ship_family, is set to AF_HIP. The port number ship_port is two
octets in network byte order. and the ship_hit is 16 octets in
network byte order. An implementation may have extra member(s) in
this structure.
The application usually sets the ship_hit field using the resolver.
However, the application can use three special wildcard macros to set
a value directly into the ship_hit field. The macros are
HIP_HIT_ANY, HIP_HIT_ANY_PUB, HIP_HIT_ANY_TMP and HIP_ADDR_ANY. The
first three equal to a HIT value associated with a wildcard HIT of
any, public, or anonymous type. The fourth macro, HIP_ADDR_ANY,
denotes both HIP_HIT_ANY or any IPv4 or IPv6 address. The
HIP_HIT_ANY equals to HIP_HIT_ANY_PUB or HIP_HIT_ANY_TMP. The
anonymous identifiers refer to the use anonymous identifiers as
specified in [RFC4423]. The system may designate anonymous
identifiers as meta data associated with a HIT depending on whether
it has been published or not. However, there is no difference in the
classes of HITs from the HIP protocol perspective,
The application can use the HIP_HIT_ANY_* and HIP_ADDR_ANY macros to
accept incoming communications to all of the HITs of the local host.
Incoming communications refers here to the functions such as bind(),
recvfrom() and recvmsg(). The HIP_HIT_* macros are similar to the
sockets API macros INADDR_ANY and IN6ADDR_ANY_INIT, but they are
applicable to HITs only. After initial contact with the peer, the
application can discover the local and peer HITs using getsockname()
and getpeername() calls in the context of connection oriented
sockets. The difference between the use of the HIP_HIT_* and
HIP_ADDR_ANY macros here is that the former allows only HIP-based
communications but the latter also allows communications without HIP.
The application also uses the HIP_HIT_ANY macro in ship_hit field to
establish outgoing communications in Opportunistic mode [RFC5201],
i.e., when the application knows the remote peer locator but not the
HIT. Outgoing communications refers here to the use of functions
such as connect(), sendto() and sendmsg(). However, the application
should first associate the socket with at least one IP address of the
peer using SHIM_LOCLIST_PEER_PREF socket option. The use of the
HIP_HIT_ANY macro guarantees that the communications will be based on
HIP or none at all.
The use of HIP_ADDR_ANY macro in the context of outgoing
communications is left for further experimentation. It could be used
for establishing a non-HIP based connectivity when HIP-based
connectivity was unsuccessful.
Some applications rely on system level access control, either
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implicit or explicit (such as accept_filter() function found on BSD-
based systems), but such discussion is out of scope. Other
applications implement access control themselves by using the HITs.
In such a case, the application can compare two HITs using memcmp()
or similar function. It should be noticed that different connection
attempts between the same two hosts can result in different HITs
because a host is allowed to have multiple HITs.
4.2. Extensions to Resolver Data Structures
The HIP APIs introduce a new addrinfo flag, HIP_PREFER_ORCHID, to be
used by application to query for both HIT and locator information via
the getaddrinfo() resolver function [RFC3493]. The getaddrinfo()
function uses a data structure used for both input to and output from
the resolver. The data structure is illustrated in Figure 3.
#include <netdb.h>
struct addrinfo {
int ai_flags; /* e.g. AI_EXTFLAGS */
int ai_family; /* e.g. AF_HIP */
int ai_socktype; /* e.g. SOCK_STREAM */
int ai_protocol; /* 0 or IPPROTO_HIP */
socklen_t ai_addrlen; /* size of *ai_addr */
struct sockaddr *ai_addr; /* sockaddr_hip */
char *ai_canonname; /* canon. name of the host */
struct addrinfo *ai_next; /* next endpoint */
int ai_eflags; /* RFC5014 extension */
};
Figure 3
Application must set both the flag AI_EXTFLAGS [RFC5014] in ai_flags
and HIP_PREFER_ORCHID in the ai_eflags, or otherwise the resolver
does not return sockaddr_hip data structures. The resolver returns
EAI_BADFLAGS when it does not support HIP_PREFER_ORCHID or
AI_EXTFLAGS flags.
The system may have a HIP-aware interposing DNS agent as described in
section 3.2 in [RFC5014]. In such a case, the DNS agent returns
transparently LSIs or HITs in sockaddr_in and sockaddr_in6 structures
when available. To disable this behaviour, the application sets
AI_EXTFLAGS and AI_NO_ORCHID flags.
Application denotes its preference for public and anonymous types of
HITs using HIP_PREFER_SRC_PUBLIC and HIP_PREFER_SRC_TMP flags in the
ai_eflags field. If the application sets neither of the flags, the
resolver returns both public and anonymous HITs.
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The simultaneous use of both HIP_PREFER_ORCHID and
HIP_PREFER_PASSIVE_* flags produces a single sockaddr_hip structure
containing a wildcard address that the application can use either for
incoming (node argument is NULL in getaddrinfo) or outgoing
communications (node argument is non-NULL). For example,
HIP_PREFER_PASSIVE_HIT_TMP flag produces one sockaddr_hip structure
that contains a HIP_HIT_ANY_TMP in the ship_hit field.
The resolver sets the ai_family field to AF_HIP in the addrinfo
structure when ai_addr points to a sockaddr_hip structure.
When ai_protocol field is set to zero, the resolver also returns
locators in sockaddr_in and sockaddr_in6 structures in addition to
sockaddr_hip structures. The resolver returns only sockaddr_hip
structures when the application has set the ai_protocol field to
IPPROTO_HIP or a sockaddr_hip structure is given as the hint argument
to the resolver.
4.2.1. Resolver Usage
A HIP-aware application creates the sockaddr_hip structures
explicitly or obtains them from the resolver. The explicit
configuration of locators is described in
[I-D.ietf-shim6-multihome-shim-api]. This document defines
"automated" resolver extensions for getaddrinfo() resolver [RFC3493].
#include <netdb.h>
int getaddrinfo(const char *nodename,
const char *servname,
const struct addrinfo *hints,
struct addrinfo **res)
void free_addrinfo(struct addrinfo *res)
Figure 4
As described in [RFC3493], the getaddrinfo function takes the
nodename, servname, and hints as its input arguments. It places the
result of the query into the res argument. The return value is zero
on success, or a non-zero error value on error. The nodename
argument specifies the host name to be resolved; a NULL argument
denotes the local host. The servname parameter declares the port
number to be set in the socket addresses in the res output argument.
Both the nodename and servname cannot be NULL.
The input argument "hints" acts like a filter that defines the
attributes required from the resolved endpoints. A NULL hints
argument indicates that any kind of endpoints are acceptable.
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The output argument "res" is dynamically allocated by the resolver.
The application frees res argument with the free_addrinfo function.
The res argument contains a linked list of the resolved endpoints.
The linked list contains sockaddr_hip structures only when the input
argument has the HIP_PREFER_ORCHID flag set in ai_eflags. The
resolver inserts HITs before any locators. When the
HIP_PREFER_ORCHID flag is set, the resolver does not return LSIs or
HITs encapsulated into sockaddr_in or sockaddr_in6 data structures as
described in [RFC5338].
Resolver can return a HIT which maps to multiple locators. The
resolver may cache the locator mappings to the HIP module. The HIP
module manages the multiple locators according to system policies of
the host. The multihoming document
[I-D.ietf-shim6-multihome-shim-api] describes how an application can
override system default policies.
It should be noticed that the application can configure the HIT
explicitly without setting the locator or the resolver can fail to
resolve any locator. In this scenario, the application relies on the
system to map the HIT to an IP address. When the system fails to
provide the mapping, it returns -1 in the called sockets API function
to the application and sets errno to EADDRNOTAVAIL.
4.3. The Use of getsockname and getpeername Functions
The application usually discovers the local or peer HITs from the
sockaddr_hip structures returned by getaddrinfo(). However, the
sockaddr_hip structure does not contain a HIT when the application
uses the HIP_HIT_ANY_* macros. In such a case, the application
discovers the local and peer HITs using the getsockname() and
getpeername() functions. The functions return sockaddr_hip
structures when the family of the socket is AF_HIP.
4.4. Validating HITs
An application that uses the HIP_ADDR_ANY macro may want to check if
the local or peer address is an orchid-based HIT [RFC4843]. Also,
the application may want to verify whether a HIT is public or
anonymous. The application accomplishes these using a new function
called sockaddr_is_srcaddr() which is illustrated in Figure 5.
#include <netinet/in.h>
short sockaddr_is_srcaddr(struct sockaddr *srcaddr
uint64_t flags);
Figure 5
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The sockaddr_is_srcaddr() function operates in the same way as
inet6_is_srcaddr() function [RFC5014] which can be used to verify the
type of an address belonging to the localhost. The difference is
that sockaddr_is_srcaddr() function handles sockaddr_hip structures
in addition to sockaddr_in6, and possibly some other socket
structures in further extensions. The function has also 64 bit flags
instead of 32 bits. This new function handles the same flags as
defined in [RFC5014] in addition to some HIP-specific flags listed in
Table 2.
+-----------------------+-------------------------+
| Flag | Purpose |
+-----------------------+-------------------------+
| HIP_PREFER_ORCHID | The identifier is a HIT |
| HIP_PREFER_SRC_TMP | Anonymous HIT |
| HIP_PREFER_SRC_PUBLIC | Public HIT |
+-----------------------+-------------------------+
Table 2
4.5. Source HIT Selection by the System
Some applications initiate communications by specifying only the
destination identifier and let the underlying system specify the
source. When the system selects the source HIT, the system should
apply the rules specified in [RFC3484] according to the default
policy table for HITs shown in Table 3.
+-----------------+------------+-------+
| HIT Type | Precedence | Label |
+-----------------+------------+-------+
| Anonymous DSA | 110 | 5 |
| Anonymous RSA | 120 | 6 |
| Public DSA | 130 | 7 |
| Public RSA | 140 | 8 |
| [RFC3484] rules | 50-100 | 7 |
+-----------------+------------+-------+
Table 3
When application using a AF_HIP-based socket does not specify the
source identifier, the system selects the source identifier on the
behalf of the application according to the precedence in the above
table. For example, the system prefers public (published) keys
before anonymous keys because they work better for referral purposes.
RSA-based keys are preferred over DSA based because RSA is the
default algorithm in HIP.
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When system provides multiple keys of same type, but with different
key lengths, the longer keys should have a higher preference. As
example, system providing two public RSA keys of different size would
give the smaller key preference value 140 and 145 for the larger.
The preference value should not exceed 150. Systems supporting more
than 10 keys of same key size may use digits to further fragment the
precedence namespace. IPv6 addresses have the lowest precedence
value to denote that HITs have a higher precedence when operating on
AF_HIP-based sockets.
[RFC5014] specifies flags for the getaddrinfo resolver and socket
options for Mobile IPv6. The resolver, operating under
HIP_PREFER_ORCHID flag, or the socket handler, operating on a AF_HIP-
based socket, may encounter such flags or options. In such a case
the resolver or socket handler should silenty ignore the flags or
options without returning an error. However, a HIP-aware application
may use the HIP-specific flags HIP_PREFER_ORCHID, HIP_PREFER_SRC_TMP
or HIP_PREFER_SRC_PUBLIC in getsockopt(), setsockopt(), getaddrinfo()
calls and in the anchillary data of datagram packets as specified in
[RFC5014]. The level of the socket options should be set to SOL_SHIM
[I-D.ietf-shim6-multihome-shim-api] and the option name should be
HIP_HIT_PREFERENCES.
4.6. Explicit Handling of Locators
The system resolver, or the HIP module, maps HITs to locators
implicitly. However, some applications may want to specify initial
locator mappings explicitly. In such a case, the application first
creates a socket with AF_HIP as the domain argument. Second, the
application may set locator information with one of the following
shim socket options as defined in the multihoming extensions in
[I-D.ietf-shim6-multihome-shim-api]:
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+-----------------------------+-----+-----+-----------------+-------+
| optname | get | set | description | dtype |
+-----------------------------+-----+-----+-----------------+-------+
| SHIM_LOC_LOCAL_PREF | o | o | Get or set the | *1 |
| | | | preferred | |
| | | | locator on the | |
| | | | local side for | |
| | | | the context | |
| | | | associated with | |
| | | | the socket. | |
| SHIM_LOC_PEER_PREF | o | o | Get or set the | *1 |
| | | | preferred | |
| | | | locator on the | |
| | | | remote side for | |
| | | | the context | |
| | | | associated with | |
| | | | the socket. | |
| SHIM_LOCLIST_LOCAL | o | o | Get or set a | *2 |
| | | | list of | |
| | | | locators | |
| | | | associated with | |
| | | | the local EID. | |
| SHIM_LOCLIST_PEER | o | o | Get or set a | *2 |
| | | | list of | |
| | | | locators | |
| | | | associated with | |
| | | | the peer's EID. | |
| SHIM_LOC_LOCAL_SEND | o | o | Request use of | *2 |
| | | | specific | |
| | | | locator as | |
| | | | source locator | |
| | | | of outgoing IP | |
| | | | packets. | |
| SHIM_LOC_PEER_SEND | o | o | Request use of | *2 |
| | | | specific | |
| | | | locator as | |
| | | | destination | |
| | | | locator of | |
| | | | outgoing IP | |
| | | | packets. | |
+-----------------------------+-----+-----+-----------------+-------+
*1: Pointer to a shim_locator which is defined in Section 7 of
draft-ietf-shim6-multihome-shim-api.
*2: Pointer to an array of shim_locator.
Figure 6
Finally, the application creates a valid sockaddr_hip structure and
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associates the socket also with the sockaddr_hip structure by calling
some socket-related function, such as connect() or bind().
The usage and semantics for typical use cases are as follows:
An application that initiates a connection using a connection
oriented socket to a particular host at a known address or set of
addresses can invoke SHIM_LOCLIST_PEER socket option. The HIP module
uses the first address (if multiple are provided, or else the
application can override this by setting SHIM_LOC_PEER_PREF to one of
the addresses in SHIM_LOCLIST_PEER. The application later provides a
specific HIT in the ship_hit field of the sockaddr_hip in the
connect() system call. If the application provides one or more
addresses in SHIM_LOCLIST_PEER setsockopt call, the system should not
connect to the host via another destination address, in case the
application intends to restrict the range of addresses permissible as
a policy choice. If the system cannot reach the provided HIT at one
of the addresses provided, the outbound socket API functions
(connect, sendmsg, etc.) return -1 and set errno to EINVALIDLOCATOR.
Another common use case is to set up an association in opportunistic
mode, when the destination HIT is specified as a wildcard. This can
be accomplished by setting one or more destination addresses using
the SHIM_LOCLIST_PEER socket option as described above and then
calling connect() with the wildcard HIT. The connect() call returns
-1 and sets errno to EADDRNOTAVAIL when the application connects to a
wildcard without specifying any destination address.
Applications may also choose to associate local addresses with
sockets. The procedures specified in
[I-D.ietf-shim6-multihome-shim-api] are followed in this case.
5. Summary of New Definitions
Table 4 summarizes the new macro and structures defined in this
document.
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+-----------------+-----------------------------+
| Header | Definition |
+-----------------+-----------------------------+
| <sys/socket.h> | AF_HIP |
| <sys/socket.h> | PF_HIP |
| <netinet/in.h> | IPPROTO_HIP |
| <netinet/hip.h> | HIP_HIT_ANY |
| <netinet/hip.h> | HIP_HIT_ANY_PUB |
| <netinet/hip.h> | HIP_HIT_ANY_TMP |
| <netinet/hip.h> | HIP_ADDR_ANY |
| <netinet/hip.h> | HIP_HIT_PREFERENCES |
| <netinet/hip.h> | hip_hit_t |
| <netdb.h> | HIP_PREFER_ORCHID |
| <netdb.h> | HIP_PREFER_SRC_TMP |
| <netdb.h> | HIP_PREFER_SRC_PUBLIC |
| <netdb.h> | HIP_PREFER_PASSIVE_HIT_TMP |
| <netdb.h> | HIP_PREFER_PASSIVE_HIT_PUB |
| <netdb.h> | HIP_PREFER_PASSIVE_HIT_ANY |
| <netdb.h> | HIP_PREFER_PASSIVE_ADDR_ANY |
| <netinet/hip.h> | sockaddr_hip |
| <netinet/hip.h> | sockaddr_is_srcaddr |
+-----------------+-----------------------------+
Table 4
6. IANA Considerations
No IANA considerations.
7. Security Considerations
No security considerations currently.
8. Contributors
Thanks for Jukka Ylitalo and Pekka Nikander for their original
contribution, time and effort to the native HIP APIs. Thanks for
Yoshifuji Hideaki for his contributions to this document.
9. Acknowledgements
Kristian Slavov, Julien Laganier, Jaakko Kangasharju, Mika Kousa, Jan
Melen, Andrew McGregor, Sasu Tarkoma, Lars Eggert, Joe Touch, Antti
Jaervinen, Anthony Joseph, Teemu Koponen, Jari Arkko, Ari Keraenen,
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Internet-Draft Basic API Extensions for HIP May 2009
Juha-Matti Tapio, Shinta Sugimoto, Philip Matthews, Jan Melen and
Gonzalo Camarillo have also provided valuable ideas or feedback.
Thanks also for the APPS area folks, including Stephane Bortzmeyer,
Chris Newman, Tony Finch, "der Mouse" and Keith Moore.
10. Normative References
[I-D.ietf-btns-c-api]
Richardson, M., Williams, N., Komu, M., and S. Tarkoma,
"C-Bindings for IPsec Application Programming Interfaces",
draft-ietf-btns-c-api-04 (work in progress), March 2009.
[I-D.ietf-shim6-multihome-shim-api]
Komu, M., Bagnulo, M., Slavov, K., and S. Sugimoto,
"Socket Application Program Interface (API) for
Multihoming Shim", draft-ietf-shim6-multihome-shim-api-08
(work in progress), May 2009.
[I-D.ietf-shim6-proto]
Nordmark, E. and M. Bagnulo, "Shim6: Level 3 Multihoming
Shim Protocol for IPv6", draft-ietf-shim6-proto-12 (work
in progress), February 2009.
[POSIX] Institute of Electrical and Electronics Engineers, "IEEE
Std. 1003.1-2001 Standard for Information Technology -
Portable Operating System Interface (POSIX)", Dec 2001.
[RFC3484] Draves, R., "Default Address Selection for Internet
Protocol version 6 (IPv6)", RFC 3484, February 2003.
[RFC3493] Gilligan, R., Thomson, S., Bound, J., McCann, J., and W.
Stevens, "Basic Socket Interface Extensions for IPv6",
RFC 3493, February 2003.
[RFC4423] Moskowitz, R. and P. Nikander, "Host Identity Protocol
(HIP) Architecture", RFC 4423, May 2006.
[RFC4843] Nikander, P., Laganier, J., and F. Dupont, "An IPv6 Prefix
for Overlay Routable Cryptographic Hash Identifiers
(ORCHID)", RFC 4843, April 2007.
[RFC5014] Nordmark, E., Chakrabarti, S., and J. Laganier, "IPv6
Socket API for Source Address Selection", RFC 5014,
September 2007.
[RFC5201] Moskowitz, R., Nikander, P., Jokela, P., and T. Henderson,
"Host Identity Protocol", RFC 5201, April 2008.
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[RFC5205] Nikander, P. and J. Laganier, "Host Identity Protocol
(HIP) Domain Name System (DNS) Extensions", RFC 5205,
April 2008.
[RFC5338] Henderson, T., Nikander, P., and M. Komu, "Using the Host
Identity Protocol with Legacy Applications", RFC 5338,
September 2008.
Authors' Addresses
Miika Komu
Helsinki Institute for Information Technology
Metsaenneidonkuja 4
Helsinki
Finland
Phone: +358503841531
Fax: +35896949768
Email: miika@iki.fi
URI: http://www.iki.fi/miika/
Thomas Henderson
The Boeing Company
P.O. Box 3707
Seattle, WA
USA
Email: thomas.r.henderson@boeing.com
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