freebsd-dev/sys/netinet6/scope6.c
George V. Neville-Neil 026e67b69b Reviewed by: SUZUKI Shinsuke <suz@kame.net>
Approved by:  Robert Watson <rwatson@freebsd.org>

Add locking to the IPv6 scoping code.

All spl() like calls have also been removed.

Cleaning up the handling of ifnet data will happen at a later date.
2004-11-29 03:10:35 +00:00

395 lines
9.2 KiB
C

/* $FreeBSD$ */
/* $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ */
/*
* Copyright (C) 2000 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/queue.h>
#include <net/route.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet6/in6_var.h>
#include <netinet6/scope6_var.h>
/*
* The scope6_lock protects the global sid default stored in
* sid_default below.
*/
static struct mtx scope6_lock;
#define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF)
#define SCOPE6_LOCK() mtx_lock(&scope6_lock)
#define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock)
#define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED)
static struct scope6_id sid_default;
#define SID(ifp) \
(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
void
scope6_init()
{
SCOPE6_LOCK_INIT();
bzero(&sid_default, sizeof(sid_default));
}
struct scope6_id *
scope6_ifattach(ifp)
struct ifnet *ifp;
{
struct scope6_id *sid;
sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK);
bzero(sid, sizeof(*sid));
/*
* XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
* Should we rather hardcode here?
*/
sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index;
sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
#ifdef MULTI_SCOPE
/* by default, we don't care about scope boundary for these scopes. */
sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1;
sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1;
#endif
return sid;
}
void
scope6_ifdetach(sid)
struct scope6_id *sid;
{
free(sid, M_IFADDR);
}
int
scope6_set(ifp, idlist)
struct ifnet *ifp;
struct scope6_id *idlist;
{
int i;
int error = 0;
struct scope6_id *sid = NULL;
IF_AFDATA_LOCK(ifp);
sid = SID(ifp);
if (!sid) { /* paranoid? */
IF_AFDATA_UNLOCK(ifp);
return (EINVAL);
}
/*
* XXX: We need more consistency checks of the relationship among
* scopes (e.g. an organization should be larger than a site).
*/
/*
* TODO(XXX): after setting, we should reflect the changes to
* interface addresses, routing table entries, PCB entries...
*/
SCOPE6_LOCK();
for (i = 0; i < 16; i++) {
if (idlist->s6id_list[i] &&
idlist->s6id_list[i] != sid->s6id_list[i]) {
/*
* An interface zone ID must be the corresponding
* interface index by definition.
*/
if (i == IPV6_ADDR_SCOPE_INTFACELOCAL &&
idlist->s6id_list[i] != ifp->if_index) {
IF_AFDATA_UNLOCK(ifp);
SCOPE6_UNLOCK();
return (EINVAL);
}
if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
idlist->s6id_list[i] > if_index) {
/*
* XXX: theoretically, there should be no
* relationship between link IDs and interface
* IDs, but we check the consistency for
* safety in later use.
*/
IF_AFDATA_UNLOCK(ifp);
SCOPE6_UNLOCK();
return (EINVAL);
}
/*
* XXX: we must need lots of work in this case,
* but we simply set the new value in this initial
* implementation.
*/
sid->s6id_list[i] = idlist->s6id_list[i];
}
}
SCOPE6_UNLOCK();
IF_AFDATA_UNLOCK(ifp);
return (error);
}
int
scope6_get(ifp, idlist)
struct ifnet *ifp;
struct scope6_id *idlist;
{
/* We only need to lock the interface's afdata for SID() to work. */
IF_AFDATA_LOCK(ifp);
struct scope6_id *sid = SID(ifp);
if (sid == NULL) { /* paranoid? */
IF_AFDATA_UNLOCK(ifp);
return (EINVAL);
}
SCOPE6_LOCK();
*idlist = *sid;
SCOPE6_UNLOCK();
IF_AFDATA_UNLOCK(ifp);
return (0);
}
/*
* Get a scope of the address. Node-local, link-local, site-local or global.
*/
int
in6_addrscope(addr)
struct in6_addr *addr;
{
int scope;
if (addr->s6_addr[0] == 0xfe) {
scope = addr->s6_addr[1] & 0xc0;
switch (scope) {
case 0x80:
return IPV6_ADDR_SCOPE_LINKLOCAL;
break;
case 0xc0:
return IPV6_ADDR_SCOPE_SITELOCAL;
break;
default:
return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
break;
}
}
if (addr->s6_addr[0] == 0xff) {
scope = addr->s6_addr[1] & 0x0f;
/*
* due to other scope such as reserved,
* return scope doesn't work.
*/
switch (scope) {
case IPV6_ADDR_SCOPE_INTFACELOCAL:
return IPV6_ADDR_SCOPE_INTFACELOCAL;
break;
case IPV6_ADDR_SCOPE_LINKLOCAL:
return IPV6_ADDR_SCOPE_LINKLOCAL;
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
return IPV6_ADDR_SCOPE_SITELOCAL;
break;
default:
return IPV6_ADDR_SCOPE_GLOBAL;
break;
}
}
/*
* Regard loopback and unspecified addresses as global, since
* they have no ambiguity.
*/
if (bcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) {
if (addr->s6_addr[15] == 1) /* loopback */
return IPV6_ADDR_SCOPE_LINKLOCAL;
if (addr->s6_addr[15] == 0) /* unspecified */
return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */
}
return IPV6_ADDR_SCOPE_GLOBAL;
}
/*
* When we introduce the "4+28" split semantics in sin6_scope_id,
* a 32bit integer is not enough to tell a large ID from an error (-1).
* So, we intentionally use a large type as the return value.
*/
int
in6_addr2zoneid(ifp, addr, ret_id)
struct ifnet *ifp; /* must not be NULL */
struct in6_addr *addr; /* must not be NULL */
u_int32_t *ret_id; /* must not be NULL */
{
int scope;
u_int32_t zoneid = 0;
struct scope6_id *sid = NULL;
IF_AFDATA_LOCK(ifp);
sid = SID(ifp);
#ifdef DIAGNOSTIC
if (sid == NULL) { /* should not happen */
panic("in6_addr2zoneid: scope array is NULL");
/* NOTREACHED */
}
if (ret_id == NULL) {
panic("in6_addr2zoneid: return ID is null");
/* NOTREACHED */
}
#endif
/*
* special case: the loopback address can only belong to a loopback
* interface.
*/
if (IN6_IS_ADDR_LOOPBACK(addr)) {
if (!(ifp->if_flags & IFF_LOOPBACK)) {
IF_AFDATA_UNLOCK(ifp);
return (-1);
} else {
*ret_id = 0; /* there's no ambiguity */
IF_AFDATA_UNLOCK(ifp);
return (0);
}
}
scope = in6_addrscope(addr);
/*
* XXX: These are all u_int32_t reads, so may not require locking.
*/
SCOPE6_LOCK();
switch (scope) {
case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */
zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL];
break;
case IPV6_ADDR_SCOPE_LINKLOCAL:
zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL];
break;
case IPV6_ADDR_SCOPE_SITELOCAL:
zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL];
break;
case IPV6_ADDR_SCOPE_ORGLOCAL:
zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL];
break;
default:
zoneid = 0; /* XXX: treat as global. */
break;
}
SCOPE6_UNLOCK();
*ret_id = zoneid;
IF_AFDATA_UNLOCK(ifp);
return (0);
}
void
scope6_setdefault(ifp)
struct ifnet *ifp; /* note that this might be NULL */
{
/*
* Currently, this function just sets the default "interfaces"
* and "links" according to the given interface.
* We might eventually have to separate the notion of "link" from
* "interface" and provide a user interface to set the default.
*/
SCOPE6_LOCK();
if (ifp) {
sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
ifp->if_index;
sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
ifp->if_index;
} else {
sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
}
SCOPE6_UNLOCK();
}
int
scope6_get_default(idlist)
struct scope6_id *idlist;
{
SCOPE6_LOCK();
*idlist = sid_default;
SCOPE6_UNLOCK();
return (0);
}
u_int32_t
scope6_addr2default(addr)
struct in6_addr *addr;
{
u_int32_t id;
/*
* special case: The loopback address should be considered as
* link-local, but there's no ambiguity in the syntax.
*/
if (IN6_IS_ADDR_LOOPBACK(addr))
return (0);
/*
* XXX: 32-bit read is atomic on all our platforms, is it OK
* not to lock here?
*/
SCOPE6_LOCK();
id = sid_default.s6id_list[in6_addrscope(addr)];
SCOPE6_UNLOCK();
return (id);
}