freebsd-skq/sys/netinet6/scope6.c
Pedro F. Giffuni 51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00

575 lines
14 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
*
* $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/systm.h>
#include <sys/queue.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet6/in6_var.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#ifdef ENABLE_DEFAULT_SCOPE
VNET_DEFINE(int, ip6_use_defzone) = 1;
#else
VNET_DEFINE(int, ip6_use_defzone) = 0;
#endif
VNET_DEFINE(int, deembed_scopeid) = 1;
SYSCTL_DECL(_net_inet6_ip6);
SYSCTL_INT(_net_inet6_ip6, OID_AUTO, deembed_scopeid, CTLFLAG_VNET | CTLFLAG_RW,
&VNET_NAME(deembed_scopeid), 0,
"Extract embedded zone ID and set it to sin6_scope_id in sockaddr_in6.");
/*
* 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 VNET_DEFINE(struct scope6_id, sid_default);
#define V_sid_default VNET(sid_default)
#define SID(ifp) \
(((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id)
static int scope6_get(struct ifnet *, struct scope6_id *);
static int scope6_set(struct ifnet *, struct scope6_id *);
void
scope6_init(void)
{
bzero(&V_sid_default, sizeof(V_sid_default));
if (!IS_DEFAULT_VNET(curvnet))
return;
SCOPE6_LOCK_INIT();
}
struct scope6_id *
scope6_ifattach(struct ifnet *ifp)
{
struct scope6_id *sid;
sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO);
/*
* 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;
return (sid);
}
void
scope6_ifdetach(struct scope6_id *sid)
{
free(sid, M_IFADDR);
}
int
scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp)
{
struct in6_ifreq *ifr;
if (ifp->if_afdata[AF_INET6] == NULL)
return (EPFNOSUPPORT);
ifr = (struct in6_ifreq *)data;
switch (cmd) {
case SIOCSSCOPE6:
return (scope6_set(ifp,
(struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
case SIOCGSCOPE6:
return (scope6_get(ifp,
(struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
case SIOCGSCOPE6DEF:
return (scope6_get_default(
(struct scope6_id *)ifr->ifr_ifru.ifru_scope_id));
default:
return (EOPNOTSUPP);
}
}
static int
scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
{
int i;
int error = 0;
struct scope6_id *sid = NULL;
IF_AFDATA_WLOCK(ifp);
sid = SID(ifp);
if (!sid) { /* paranoid? */
IF_AFDATA_WUNLOCK(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...
*/
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_WUNLOCK(ifp);
return (EINVAL);
}
if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
idlist->s6id_list[i] > V_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_WUNLOCK(ifp);
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];
}
}
IF_AFDATA_WUNLOCK(ifp);
return (error);
}
static int
scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
{
struct scope6_id *sid;
/* We only need to lock the interface's afdata for SID() to work. */
IF_AFDATA_RLOCK(ifp);
sid = SID(ifp);
if (sid == NULL) { /* paranoid? */
IF_AFDATA_RUNLOCK(ifp);
return (EINVAL);
}
*idlist = *sid;
IF_AFDATA_RUNLOCK(ifp);
return (0);
}
/*
* Get a scope of the address. Node-local, link-local, site-local or global.
*/
int
in6_addrscope(const struct in6_addr *addr)
{
if (IN6_IS_ADDR_MULTICAST(addr)) {
/*
* Addresses with reserved value F must be treated as
* global multicast addresses.
*/
if (IPV6_ADDR_MC_SCOPE(addr) == 0x0f)
return (IPV6_ADDR_SCOPE_GLOBAL);
return (IPV6_ADDR_MC_SCOPE(addr));
}
if (IN6_IS_ADDR_LINKLOCAL(addr) ||
IN6_IS_ADDR_LOOPBACK(addr))
return (IPV6_ADDR_SCOPE_LINKLOCAL);
if (IN6_IS_ADDR_SITELOCAL(addr))
return (IPV6_ADDR_SCOPE_SITELOCAL);
return (IPV6_ADDR_SCOPE_GLOBAL);
}
/*
* ifp - note that this might be NULL
*/
void
scope6_setdefault(struct ifnet *ifp)
{
/*
* 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) {
V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
ifp->if_index;
V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
ifp->if_index;
} else {
V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
}
SCOPE6_UNLOCK();
}
int
scope6_get_default(struct scope6_id *idlist)
{
SCOPE6_LOCK();
*idlist = V_sid_default;
SCOPE6_UNLOCK();
return (0);
}
u_int32_t
scope6_addr2default(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 = V_sid_default.s6id_list[in6_addrscope(addr)];
SCOPE6_UNLOCK();
return (id);
}
/*
* Validate the specified scope zone ID in the sin6_scope_id field. If the ID
* is unspecified (=0), needs to be specified, and the default zone ID can be
* used, the default value will be used.
* This routine then generates the kernel-internal form: if the address scope
* of is interface-local or link-local, embed the interface index in the
* address.
*/
int
sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok)
{
u_int32_t zoneid;
if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok)
zoneid = scope6_addr2default(&sin6->sin6_addr);
if (zoneid != 0 &&
(IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) {
/*
* At this moment, we only check interface-local and
* link-local scope IDs, and use interface indices as the
* zone IDs assuming a one-to-one mapping between interfaces
* and links.
*/
if (V_if_index < zoneid || ifnet_byindex(zoneid) == NULL)
return (ENXIO);
/* XXX assignment to 16bit from 32bit variable */
sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff);
sin6->sin6_scope_id = 0;
}
return 0;
}
/*
* generate standard sockaddr_in6 from embedded form.
*/
int
sa6_recoverscope(struct sockaddr_in6 *sin6)
{
char ip6buf[INET6_ADDRSTRLEN];
u_int32_t zoneid;
if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) ||
IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) {
/*
* KAME assumption: link id == interface id
*/
zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]);
if (zoneid) {
/* sanity check */
if (V_if_index < zoneid)
return (ENXIO);
#if 0
/* XXX: Disabled due to possible deadlock. */
if (!ifnet_byindex(zoneid))
return (ENXIO);
#endif
if (sin6->sin6_scope_id != 0 &&
zoneid != sin6->sin6_scope_id) {
log(LOG_NOTICE,
"%s: embedded scope mismatch: %s%%%d. "
"sin6_scope_id was overridden\n", __func__,
ip6_sprintf(ip6buf, &sin6->sin6_addr),
sin6->sin6_scope_id);
}
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id = zoneid;
}
}
return 0;
}
/*
* Determine the appropriate scope zone ID for in6 and ifp. If ret_id is
* non NULL, it is set to the zone ID. If the zone ID needs to be embedded
* in the in6_addr structure, in6 will be modified.
*
* ret_id - unnecessary?
*/
int
in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
{
int scope;
u_int32_t zoneid = 0;
struct scope6_id *sid;
/*
* special case: the loopback address can only belong to a loopback
* interface.
*/
if (IN6_IS_ADDR_LOOPBACK(in6)) {
if (!(ifp->if_flags & IFF_LOOPBACK))
return (EINVAL);
} else {
scope = in6_addrscope(in6);
if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL ||
scope == IPV6_ADDR_SCOPE_LINKLOCAL) {
/*
* Currently we use interface indeces as the
* zone IDs for interface-local and link-local
* scopes.
*/
zoneid = ifp->if_index;
in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
} else if (scope != IPV6_ADDR_SCOPE_GLOBAL) {
IF_AFDATA_RLOCK(ifp);
sid = SID(ifp);
zoneid = sid->s6id_list[scope];
IF_AFDATA_RUNLOCK(ifp);
}
}
if (ret_id != NULL)
*ret_id = zoneid;
return (0);
}
/*
* Just clear the embedded scope identifier. Return 0 if the original address
* is intact; return non 0 if the address is modified.
*/
int
in6_clearscope(struct in6_addr *in6)
{
int modified = 0;
if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
if (in6->s6_addr16[1] != 0)
modified = 1;
in6->s6_addr16[1] = 0;
}
return (modified);
}
/*
* Return the scope identifier or zero.
*/
uint16_t
in6_getscope(struct in6_addr *in6)
{
if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6))
return (in6->s6_addr16[1]);
return (0);
}
/*
* Return pointer to ifnet structure, corresponding to the zone id of
* link-local scope.
*/
struct ifnet*
in6_getlinkifnet(uint32_t zoneid)
{
return (ifnet_byindex((u_short)zoneid));
}
/*
* Return zone id for the specified scope.
*/
uint32_t
in6_getscopezone(const struct ifnet *ifp, int scope)
{
if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL ||
scope == IPV6_ADDR_SCOPE_LINKLOCAL)
return (ifp->if_index);
if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT)
return (SID(ifp)->s6id_list[scope]);
return (0);
}
/*
* Extracts scope from adddress @dst, stores cleared address
* inside @dst and zone inside @scopeid
*/
void
in6_splitscope(const struct in6_addr *src, struct in6_addr *dst,
uint32_t *scopeid)
{
uint32_t zoneid;
*dst = *src;
zoneid = ntohs(in6_getscope(dst));
in6_clearscope(dst);
*scopeid = zoneid;
}
/*
* This function is for checking sockaddr_in6 structure passed
* from the application level (usually).
*
* sin6_scope_id should be set for link-local unicast, link-local and
* interface-local multicast addresses.
*
* If it is zero, then look into default zone ids. If default zone id is
* not set or disabled, then return error.
*/
int
sa6_checkzone(struct sockaddr_in6 *sa6)
{
int scope;
scope = in6_addrscope(&sa6->sin6_addr);
if (scope == IPV6_ADDR_SCOPE_GLOBAL)
return (sa6->sin6_scope_id ? EINVAL: 0);
if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) &&
scope != IPV6_ADDR_SCOPE_LINKLOCAL &&
scope != IPV6_ADDR_SCOPE_INTFACELOCAL) {
if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0)
sa6->sin6_scope_id = V_sid_default.s6id_list[scope];
return (0);
}
/*
* Since ::1 address always configured on the lo0, we can
* automatically set its zone id, when it is not specified.
* Return error, when specified zone id doesn't match with
* actual value.
*/
if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) {
if (sa6->sin6_scope_id == 0)
sa6->sin6_scope_id = in6_getscopezone(V_loif, scope);
else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope))
return (EADDRNOTAVAIL);
}
/* XXX: we can validate sin6_scope_id here */
if (sa6->sin6_scope_id != 0)
return (0);
if (V_ip6_use_defzone != 0)
sa6->sin6_scope_id = V_sid_default.s6id_list[scope];
/* Return error if we can't determine zone id */
return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL);
}
/*
* This function is similar to sa6_checkzone, but it uses given ifp
* to initialize sin6_scope_id.
*/
int
sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6)
{
int scope;
scope = in6_addrscope(&sa6->sin6_addr);
if (scope == IPV6_ADDR_SCOPE_LINKLOCAL ||
scope == IPV6_ADDR_SCOPE_INTFACELOCAL) {
if (sa6->sin6_scope_id == 0) {
sa6->sin6_scope_id = in6_getscopezone(ifp, scope);
return (0);
} else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope))
return (EADDRNOTAVAIL);
}
return (sa6_checkzone(sa6));
}