freebsd-skq/sys/netinet6/in6_src.c
andre 6164d7c280 Introduce tcp_hostcache and remove the tcp specific metrics from
the routing table.  Move all usage and references in the tcp stack
from the routing table metrics to the tcp hostcache.

It caches measured parameters of past tcp sessions to provide better
initial start values for following connections from or to the same
source or destination.  Depending on the network parameters to/from
the remote host this can lead to significant speedups for new tcp
connections after the first one because they inherit and shortcut
the learning curve.

tcp_hostcache is designed for multiple concurrent access in SMP
environments with high contention and is hash indexed by remote
ip address.

It removes significant locking requirements from the tcp stack with
regard to the routing table.

Reviewed by:	sam (mentor), bms
Reviewed by:	-net, -current, core@kame.net (IPv6 parts)
Approved by:	re (scottl)
2003-11-20 20:07:39 +00:00

1213 lines
33 KiB
C

/* $FreeBSD$ */
/* $KAME: in6_src.c,v 1.132 2003/08/26 04:42:27 keiichi Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 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.
*/
/*
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)in_pcb.c 8.2 (Berkeley) 1/4/94
*/
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#ifdef ENABLE_DEFAULT_SCOPE
#include <netinet6/scope6_var.h>
#endif
#include <net/net_osdep.h>
static struct mtx addrsel_lock;
#define ADDRSEL_LOCK_INIT() mtx_init(&addrsel_lock, "addrsel_lock", NULL, MTX_DEF)
#define ADDRSEL_LOCK() mtx_lock(&addrsel_lock)
#define ADDRSEL_UNLOCK() mtx_unlock(&addrsel_lock)
#define ADDRSEL_LOCK_ASSERT() mtx_assert(&addrsel_lock, MA_OWNED)
#define ADDR_LABEL_NOTAPP (-1)
struct in6_addrpolicy defaultaddrpolicy;
int ip6_prefer_tempaddr = 0;
static int in6_selectif __P((struct sockaddr_in6 *, struct ip6_pktopts *,
struct ip6_moptions *,
struct route_in6 *ro,
struct ifnet **));
static struct in6_addrpolicy *lookup_addrsel_policy __P((struct sockaddr_in6 *));
static void init_policy_queue __P((void));
static int add_addrsel_policyent __P((struct in6_addrpolicy *));
static int delete_addrsel_policyent __P((struct in6_addrpolicy *));
static int walk_addrsel_policy __P((int (*)(struct in6_addrpolicy *, void *),
void *));
static int dump_addrsel_policyent __P((struct in6_addrpolicy *, void *));
static struct in6_addrpolicy *match_addrsel_policy __P((struct sockaddr_in6 *));
/*
* Return an IPv6 address, which is the most appropriate for a given
* destination and user specified options.
* If necessary, this function lookups the routing table and returns
* an entry to the caller for later use.
*/
#define REPLACE(r) do {\
if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \
sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
ip6stat.ip6s_sources_rule[(r)]++; \
/* printf("in6_selectsrc: replace %s with %s by %d\n", ia_best ? ip6_sprintf(&ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(&ia->ia_addr.sin6_addr), (r)); */ \
goto replace; \
} while(0)
#define NEXT(r) do {\
if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \
sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
ip6stat.ip6s_sources_rule[(r)]++; \
/* printf("in6_selectsrc: keep %s against %s by %d\n", ia_best ? ip6_sprintf(&ia_best->ia_addr.sin6_addr) : "none", ip6_sprintf(&ia->ia_addr.sin6_addr), (r)); */ \
goto next; /* XXX: we can't use 'continue' here */ \
} while(0)
#define BREAK(r) do { \
if ((r) < sizeof(ip6stat.ip6s_sources_rule) / \
sizeof(ip6stat.ip6s_sources_rule[0])) /* check for safety */ \
ip6stat.ip6s_sources_rule[(r)]++; \
goto out; /* XXX: we can't use 'break' here */ \
} while(0)
struct in6_addr *
in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp)
struct sockaddr_in6 *dstsock;
struct ip6_pktopts *opts;
struct ip6_moptions *mopts;
struct route_in6 *ro;
struct in6_addr *laddr;
int *errorp;
{
struct in6_addr *dst;
struct ifnet *ifp = NULL;
struct in6_ifaddr *ia = NULL, *ia_best = NULL;
struct in6_pktinfo *pi = NULL;
int dst_scope = -1, best_scope = -1, best_matchlen = -1;
struct in6_addrpolicy *dst_policy = NULL, *best_policy = NULL;
u_int32_t odstzone;
int prefer_tempaddr;
struct sockaddr_in6 dstsock0;
dstsock0 = *dstsock;
if (IN6_IS_SCOPE_LINKLOCAL(&dstsock0.sin6_addr) ||
IN6_IS_ADDR_MC_INTFACELOCAL(&dstsock0.sin6_addr)) {
/* KAME assumption: link id == interface id */
if (opts && opts->ip6po_pktinfo &&
opts->ip6po_pktinfo->ipi6_ifindex) {
ifp = ifnet_byindex(opts->ip6po_pktinfo->ipi6_ifindex);
dstsock0.sin6_addr.s6_addr16[1] =
htons(opts->ip6po_pktinfo->ipi6_ifindex);
} else if (mopts &&
IN6_IS_ADDR_MULTICAST(&dstsock0.sin6_addr) &&
mopts->im6o_multicast_ifp) {
ifp = mopts->im6o_multicast_ifp;
dstsock0.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
} else if ((*errorp = in6_embedscope(&dstsock0.sin6_addr,
&dstsock0, NULL, NULL)) != 0)
return (NULL);
}
dstsock = &dstsock0;
dst = &dstsock->sin6_addr;
*errorp = 0;
/*
* If the source address is explicitly specified by the caller,
* check if the requested source address is indeed a unicast address
* assigned to the node, and can be used as the packet's source
* address. If everything is okay, use the address as source.
*/
if (opts && (pi = opts->ip6po_pktinfo) &&
!IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) {
struct sockaddr_in6 srcsock;
struct in6_ifaddr *ia6;
/* get the outgoing interface */
if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp))
!= 0) {
return (NULL);
}
/*
* determine the appropriate zone id of the source based on
* the zone of the destination and the outgoing interface.
*/
bzero(&srcsock, sizeof(srcsock));
srcsock.sin6_family = AF_INET6;
srcsock.sin6_len = sizeof(srcsock);
srcsock.sin6_addr = pi->ipi6_addr;
if (ifp) {
if (in6_addr2zoneid(ifp, &pi->ipi6_addr,
&srcsock.sin6_scope_id)) {
*errorp = EINVAL; /* XXX */
return (NULL);
}
}
if ((*errorp = in6_embedscope(&srcsock.sin6_addr, &srcsock,
NULL, NULL)) != 0) {
return (NULL);
}
srcsock.sin6_scope_id = 0; /* XXX: ifa_ifwithaddr expects 0 */
ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)(&srcsock));
if (ia6 == NULL ||
(ia6->ia6_flags & (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY))) {
*errorp = EADDRNOTAVAIL;
return (NULL);
}
pi->ipi6_addr = srcsock.sin6_addr; /* XXX: this overrides pi */
return (&ia6->ia_addr.sin6_addr);
}
/*
* Otherwise, if the socket has already bound the source, just use it.
*/
if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr))
return (laddr);
/*
* If the address is not specified, choose the best one based on
* the outgoing interface and the destination address.
*/
/* get the outgoing interface */
if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, &ifp)) != 0)
return (NULL);
#ifdef DIAGNOSTIC
if (ifp == NULL) /* this should not happen */
panic("in6_selectsrc: NULL ifp");
#endif
if (in6_addr2zoneid(ifp, dst, &odstzone)) { /* impossible */
*errorp = EIO; /* XXX */
return (NULL);
}
for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
int new_scope = -1, new_matchlen = -1;
struct in6_addrpolicy *new_policy = NULL;
u_int32_t srczone, osrczone, dstzone;
struct ifnet *ifp1 = ia->ia_ifp;
/*
* We'll never take an address that breaks the scope zone
* of the destination. We also skip an address if its zone
* does not contain the outgoing interface.
* XXX: we should probably use sin6_scope_id here.
*/
if (in6_addr2zoneid(ifp1, dst, &dstzone) ||
odstzone != dstzone) {
continue;
}
if (in6_addr2zoneid(ifp, &ia->ia_addr.sin6_addr, &osrczone) ||
in6_addr2zoneid(ifp1, &ia->ia_addr.sin6_addr, &srczone) ||
osrczone != srczone) {
continue;
}
/* avoid unusable addresses */
if ((ia->ia6_flags &
(IN6_IFF_NOTREADY | IN6_IFF_ANYCAST | IN6_IFF_DETACHED))) {
continue;
}
if (!ip6_use_deprecated && IFA6_IS_DEPRECATED(ia))
continue;
/* Rule 1: Prefer same address */
if (IN6_ARE_ADDR_EQUAL(dst, &ia->ia_addr.sin6_addr)) {
ia_best = ia;
BREAK(1); /* there should be no better candidate */
}
if (ia_best == NULL)
REPLACE(0);
/* Rule 2: Prefer appropriate scope */
if (dst_scope < 0)
dst_scope = in6_addrscope(dst);
new_scope = in6_addrscope(&ia->ia_addr.sin6_addr);
if (IN6_ARE_SCOPE_CMP(best_scope, new_scope) < 0) {
if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0)
REPLACE(2);
NEXT(2);
} else if (IN6_ARE_SCOPE_CMP(new_scope, best_scope) < 0) {
if (IN6_ARE_SCOPE_CMP(new_scope, dst_scope) < 0)
NEXT(2);
REPLACE(2);
}
/*
* Rule 3: Avoid deprecated addresses. Note that the case of
* !ip6_use_deprecated is already rejected above.
*/
if (!IFA6_IS_DEPRECATED(ia_best) && IFA6_IS_DEPRECATED(ia))
NEXT(3);
if (IFA6_IS_DEPRECATED(ia_best) && !IFA6_IS_DEPRECATED(ia))
REPLACE(3);
/* Rule 4: Prefer home addresses */
/*
* XXX: This is a TODO. We should probably merge the MIP6
* case above.
*/
/* Rule 5: Prefer outgoing interface */
if (ia_best->ia_ifp == ifp && ia->ia_ifp != ifp)
NEXT(5);
if (ia_best->ia_ifp != ifp && ia->ia_ifp == ifp)
REPLACE(5);
/*
* Rule 6: Prefer matching label
* Note that best_policy should be non-NULL here.
*/
if (dst_policy == NULL)
dst_policy = lookup_addrsel_policy(dstsock);
if (dst_policy->label != ADDR_LABEL_NOTAPP) {
new_policy = lookup_addrsel_policy(&ia->ia_addr);
if (dst_policy->label == best_policy->label &&
dst_policy->label != new_policy->label)
NEXT(6);
if (dst_policy->label != best_policy->label &&
dst_policy->label == new_policy->label)
REPLACE(6);
}
/*
* Rule 7: Prefer public addresses.
* We allow users to reverse the logic by configuring
* a sysctl variable, so that privacy conscious users can
* always prefer temporary addresses.
*/
if (opts == NULL ||
opts->ip6po_prefer_tempaddr == IP6PO_TEMPADDR_SYSTEM) {
prefer_tempaddr = ip6_prefer_tempaddr;
} else if (opts->ip6po_prefer_tempaddr ==
IP6PO_TEMPADDR_NOTPREFER) {
prefer_tempaddr = 0;
} else
prefer_tempaddr = 1;
if (!(ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
(ia->ia6_flags & IN6_IFF_TEMPORARY)) {
if (prefer_tempaddr)
REPLACE(7);
else
NEXT(7);
}
if ((ia_best->ia6_flags & IN6_IFF_TEMPORARY) &&
!(ia->ia6_flags & IN6_IFF_TEMPORARY)) {
if (prefer_tempaddr)
NEXT(7);
else
REPLACE(7);
}
/*
* Rule 8: prefer addresses on alive interfaces.
* This is a KAME specific rule.
*/
if ((ia_best->ia_ifp->if_flags & IFF_UP) &&
!(ia->ia_ifp->if_flags & IFF_UP))
NEXT(8);
if (!(ia_best->ia_ifp->if_flags & IFF_UP) &&
(ia->ia_ifp->if_flags & IFF_UP))
REPLACE(8);
/*
* Rule 14: Use longest matching prefix.
* Note: in the address selection draft, this rule is
* documented as "Rule 8". However, since it is also
* documented that this rule can be overridden, we assign
* a large number so that it is easy to assign smaller numbers
* to more preferred rules.
*/
new_matchlen = in6_matchlen(&ia->ia_addr.sin6_addr, dst);
if (best_matchlen < new_matchlen)
REPLACE(14);
if (new_matchlen < best_matchlen)
NEXT(14);
/* Rule 15 is reserved. */
/*
* Last resort: just keep the current candidate.
* Or, do we need more rules?
*/
continue;
replace:
ia_best = ia;
best_scope = (new_scope >= 0 ? new_scope :
in6_addrscope(&ia_best->ia_addr.sin6_addr));
best_policy = (new_policy ? new_policy :
lookup_addrsel_policy(&ia_best->ia_addr));
best_matchlen = (new_matchlen >= 0 ? new_matchlen :
in6_matchlen(&ia_best->ia_addr.sin6_addr,
dst));
next:
continue;
out:
break;
}
if ((ia = ia_best) == NULL) {
*errorp = EADDRNOTAVAIL;
return (NULL);
}
return (&ia->ia_addr.sin6_addr);
}
static int
in6_selectif(dstsock, opts, mopts, ro, retifp)
struct sockaddr_in6 *dstsock;
struct ip6_pktopts *opts;
struct ip6_moptions *mopts;
struct route_in6 *ro;
struct ifnet **retifp;
{
int error;
struct route_in6 sro;
struct rtentry *rt = NULL;
if (ro == NULL) {
bzero(&sro, sizeof(sro));
ro = &sro;
}
if ((error = in6_selectroute(dstsock, opts, mopts, ro, retifp,
&rt, 0)) != 0) {
if (rt && rt == sro.ro_rt)
RTFREE(rt);
return (error);
}
/*
* do not use a rejected or black hole route.
* XXX: this check should be done in the L2 output routine.
* However, if we skipped this check here, we'd see the following
* scenario:
* - install a rejected route for a scoped address prefix
* (like fe80::/10)
* - send a packet to a destination that matches the scoped prefix,
* with ambiguity about the scope zone.
* - pick the outgoing interface from the route, and disambiguate the
* scope zone with the interface.
* - ip6_output() would try to get another route with the "new"
* destination, which may be valid.
* - we'd see no error on output.
* Although this may not be very harmful, it should still be confusing.
* We thus reject the case here.
*/
if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) {
int flags = (rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
if (rt && rt == sro.ro_rt)
RTFREE(rt);
return (flags);
}
/*
* Adjust the "outgoing" interface. If we're going to loop the packet
* back to ourselves, the ifp would be the loopback interface.
* However, we'd rather know the interface associated to the
* destination address (which should probably be one of our own
* addresses.)
*/
if (rt && rt->rt_ifa && rt->rt_ifa->ifa_ifp)
*retifp = rt->rt_ifa->ifa_ifp;
if (rt && rt == sro.ro_rt)
RTFREE(rt);
return (0);
}
int
in6_selectroute(dstsock, opts, mopts, ro, retifp, retrt, clone)
struct sockaddr_in6 *dstsock;
struct ip6_pktopts *opts;
struct ip6_moptions *mopts;
struct route_in6 *ro;
struct ifnet **retifp;
struct rtentry **retrt;
int clone; /* meaningful only for bsdi and freebsd. */
{
int error = 0;
struct ifnet *ifp = NULL;
struct rtentry *rt = NULL;
struct sockaddr_in6 *sin6_next;
struct in6_pktinfo *pi = NULL;
struct in6_addr *dst = &dstsock->sin6_addr;
#if 0
if (dstsock->sin6_addr.s6_addr32[0] == 0 &&
dstsock->sin6_addr.s6_addr32[1] == 0 &&
!IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) {
printf("in6_selectroute: strange destination %s\n",
ip6_sprintf(&dstsock->sin6_addr));
} else {
printf("in6_selectroute: destination = %s%%%d\n",
ip6_sprintf(&dstsock->sin6_addr),
dstsock->sin6_scope_id); /* for debug */
}
#endif
/* If the caller specify the outgoing interface explicitly, use it. */
if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) {
/* XXX boundary check is assumed to be already done. */
ifp = ifnet_byindex(pi->ipi6_ifindex);
if (ifp != NULL &&
(retrt == NULL || IN6_IS_ADDR_MULTICAST(dst))) {
/*
* we do not have to check nor get the route for
* multicast.
*/
goto done;
} else
goto getroute;
}
/*
* If the destination address is a multicast address and the outgoing
* interface for the address is specified by the caller, use it.
*/
if (IN6_IS_ADDR_MULTICAST(dst) &&
mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) {
goto done; /* we do not need a route for multicast. */
}
getroute:
/*
* If the next hop address for the packet is specified by the caller,
* use it as the gateway.
*/
if (opts && opts->ip6po_nexthop) {
struct route_in6 *ron;
sin6_next = satosin6(opts->ip6po_nexthop);
/* at this moment, we only support AF_INET6 next hops */
if (sin6_next->sin6_family != AF_INET6) {
error = EAFNOSUPPORT; /* or should we proceed? */
goto done;
}
/*
* If the next hop is an IPv6 address, then the node identified
* by that address must be a neighbor of the sending host.
*/
ron = &opts->ip6po_nextroute;
if ((ron->ro_rt &&
(ron->ro_rt->rt_flags & (RTF_UP | RTF_LLINFO)) !=
(RTF_UP | RTF_LLINFO)) ||
!SA6_ARE_ADDR_EQUAL(satosin6(&ron->ro_dst), sin6_next)) {
if (ron->ro_rt) {
RTFREE(ron->ro_rt);
ron->ro_rt = NULL;
}
*satosin6(&ron->ro_dst) = *sin6_next;
}
if (ron->ro_rt == NULL) {
rtalloc((struct route *)ron); /* multi path case? */
if (ron->ro_rt == NULL ||
!(ron->ro_rt->rt_flags & RTF_LLINFO)) {
if (ron->ro_rt) {
RTFREE(ron->ro_rt);
ron->ro_rt = NULL;
}
error = EHOSTUNREACH;
goto done;
}
}
rt = ron->ro_rt;
ifp = rt->rt_ifp;
/*
* When cloning is required, try to allocate a route to the
* destination so that the caller can store path MTU
* information.
*/
if (!clone)
goto done;
}
/*
* Use a cached route if it exists and is valid, else try to allocate
* a new one. Note that we should check the address family of the
* cached destination, in case of sharing the cache with IPv4.
*/
if (ro) {
if (ro->ro_rt &&
(!(ro->ro_rt->rt_flags & RTF_UP) ||
((struct sockaddr *)(&ro->ro_dst))->sa_family != AF_INET6 ||
!IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr,
dst))) {
RTFREE(ro->ro_rt);
ro->ro_rt = (struct rtentry *)NULL;
}
if (ro->ro_rt == (struct rtentry *)NULL) {
struct sockaddr_in6 *sa6;
/* No route yet, so try to acquire one */
bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
sa6 = (struct sockaddr_in6 *)&ro->ro_dst;
*sa6 = *dstsock;
sa6->sin6_scope_id = 0;
if (clone) {
rtalloc((struct route *)ro);
} else {
ro->ro_rt = rtalloc1(&((struct route *)ro)
->ro_dst, NULL, 0UL);
if (ro->ro_rt)
RT_UNLOCK(ro->ro_rt);
}
}
/*
* do not care about the result if we have the nexthop
* explicitly specified.
*/
if (opts && opts->ip6po_nexthop)
goto done;
if (ro->ro_rt) {
ifp = ro->ro_rt->rt_ifp;
if (ifp == NULL) { /* can this really happen? */
RTFREE(ro->ro_rt);
ro->ro_rt = NULL;
}
}
if (ro->ro_rt == NULL)
error = EHOSTUNREACH;
rt = ro->ro_rt;
/*
* Check if the outgoing interface conflicts with
* the interface specified by ipi6_ifindex (if specified).
* Note that loopback interface is always okay.
* (this may happen when we are sending a packet to one of
* our own addresses.)
*/
if (opts && opts->ip6po_pktinfo
&& opts->ip6po_pktinfo->ipi6_ifindex) {
if (!(ifp->if_flags & IFF_LOOPBACK) &&
ifp->if_index !=
opts->ip6po_pktinfo->ipi6_ifindex) {
error = EHOSTUNREACH;
goto done;
}
}
}
done:
if (ifp == NULL && rt == NULL) {
/*
* This can happen if the caller did not pass a cached route
* nor any other hints. We treat this case an error.
*/
error = EHOSTUNREACH;
}
if (error == EHOSTUNREACH)
ip6stat.ip6s_noroute++;
if (retifp != NULL)
*retifp = ifp;
if (retrt != NULL)
*retrt = rt; /* rt may be NULL */
return (error);
}
/*
* Default hop limit selection. The precedence is as follows:
* 1. Hoplimit value specified via ioctl.
* 2. (If the outgoing interface is detected) the current
* hop limit of the interface specified by router advertisement.
* 3. The system default hoplimit.
*/
int
in6_selecthlim(in6p, ifp)
struct in6pcb *in6p;
struct ifnet *ifp;
{
if (in6p && in6p->in6p_hops >= 0)
return (in6p->in6p_hops);
else if (ifp)
return (ND_IFINFO(ifp)->chlim);
else if (in6p && !IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
struct route_in6 ro6;
struct ifnet *lifp;
bzero(&ro6, sizeof(ro6));
ro6.ro_dst.sin6_family = AF_INET6;
ro6.ro_dst.sin6_len = sizeof(struct sockaddr_in6);
ro6.ro_dst.sin6_addr = in6p->in6p_faddr;
rtalloc((struct route *)&ro6);
if (ro6.ro_rt) {
lifp = ro6.ro_rt->rt_ifp;
RTFREE(ro6.ro_rt);
if (lifp)
return (ND_IFINFO(lifp)->chlim);
} else
return (ip6_defhlim);
}
return (ip6_defhlim);
}
/*
* XXX: this is borrowed from in6_pcbbind(). If possible, we should
* share this function by all *bsd*...
*/
int
in6_pcbsetport(laddr, inp, td)
struct in6_addr *laddr;
struct inpcb *inp;
struct thread *td;
{
struct socket *so = inp->inp_socket;
u_int16_t lport = 0, first, last, *lastport;
int count, error = 0, wild = 0;
struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
/* XXX: this is redundant when called from in6_pcbbind */
if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
wild = INPLOOKUP_WILDCARD;
inp->inp_flags |= INP_ANONPORT;
if (inp->inp_flags & INP_HIGHPORT) {
first = ipport_hifirstauto; /* sysctl */
last = ipport_hilastauto;
lastport = &pcbinfo->lasthi;
} else if (inp->inp_flags & INP_LOWPORT) {
if (td && (error = suser(td)))
return error;
first = ipport_lowfirstauto; /* 1023 */
last = ipport_lowlastauto; /* 600 */
lastport = &pcbinfo->lastlow;
} else {
first = ipport_firstauto; /* sysctl */
last = ipport_lastauto;
lastport = &pcbinfo->lastport;
}
/*
* Simple check to ensure all ports are not used up causing
* a deadlock here.
*
* We split the two cases (up and down) so that the direction
* is not being tested on each round of the loop.
*/
if (first > last) {
/*
* counting down
*/
count = first - last;
do {
if (count-- < 0) { /* completely used? */
/*
* Undo any address bind that may have
* occurred above.
*/
inp->in6p_laddr = in6addr_any;
return (EAGAIN);
}
--*lastport;
if (*lastport > first || *lastport < last)
*lastport = first;
lport = htons(*lastport);
} while (in6_pcblookup_local(pcbinfo,
&inp->in6p_laddr, lport, wild));
} else {
/*
* counting up
*/
count = last - first;
do {
if (count-- < 0) { /* completely used? */
/*
* Undo any address bind that may have
* occurred above.
*/
inp->in6p_laddr = in6addr_any;
return (EAGAIN);
}
++*lastport;
if (*lastport < first || *lastport > last)
*lastport = first;
lport = htons(*lastport);
} while (in6_pcblookup_local(pcbinfo,
&inp->in6p_laddr, lport, wild));
}
inp->inp_lport = lport;
if (in_pcbinshash(inp) != 0) {
inp->in6p_laddr = in6addr_any;
inp->inp_lport = 0;
return (EAGAIN);
}
return (0);
}
/*
* Generate kernel-internal form (scopeid embedded into s6_addr16[1]).
* If the address scope of is link-local, embed the interface index in the
* address. The routine determines our precedence
* between advanced API scope/interface specification and basic API
* specification.
*
* This function should be nuked in the future, when we get rid of embedded
* scopeid thing.
*
* XXX actually, it is over-specification to return ifp against sin6_scope_id.
* there can be multiple interfaces that belong to a particular scope zone
* (in specification, we have 1:N mapping between a scope zone and interfaces).
* we may want to change the function to return something other than ifp.
*/
int
in6_embedscope(in6, sin6, in6p, ifpp)
struct in6_addr *in6;
const struct sockaddr_in6 *sin6;
struct in6pcb *in6p;
struct ifnet **ifpp;
{
struct ifnet *ifp = NULL;
u_int32_t zoneid = sin6->sin6_scope_id;
*in6 = sin6->sin6_addr;
if (ifpp)
*ifpp = NULL;
/*
* don't try to read sin6->sin6_addr beyond here, since the caller may
* ask us to overwrite existing sockaddr_in6
*/
#ifdef ENABLE_DEFAULT_SCOPE
if (zoneid == 0)
zoneid = scope6_addr2default(in6);
#endif
if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
struct in6_pktinfo *pi;
/* KAME assumption: link id == interface id */
if (in6p && in6p->in6p_outputopts &&
(pi = in6p->in6p_outputopts->ip6po_pktinfo) &&
pi->ipi6_ifindex) {
ifp = ifnet_byindex(pi->ipi6_ifindex);
in6->s6_addr16[1] = htons(pi->ipi6_ifindex);
} else if (in6p && IN6_IS_ADDR_MULTICAST(in6) &&
in6p->in6p_moptions &&
in6p->in6p_moptions->im6o_multicast_ifp) {
ifp = in6p->in6p_moptions->im6o_multicast_ifp;
in6->s6_addr16[1] = htons(ifp->if_index);
} else if (zoneid) {
if (if_index < zoneid)
return (ENXIO); /* XXX EINVAL? */
ifp = ifnet_byindex(zoneid);
/* XXX assignment to 16bit from 32bit variable */
in6->s6_addr16[1] = htons(zoneid & 0xffff);
}
if (ifpp)
*ifpp = ifp;
}
return 0;
}
/*
* generate standard sockaddr_in6 from embedded form.
* touches sin6_addr and sin6_scope_id only.
*
* this function should be nuked in the future, when we get rid of
* embedded scopeid thing.
*/
int
in6_recoverscope(sin6, in6, ifp)
struct sockaddr_in6 *sin6;
const struct in6_addr *in6;
struct ifnet *ifp;
{
u_int32_t zoneid;
sin6->sin6_addr = *in6;
/*
* don't try to read *in6 beyond here, since the caller may
* ask us to overwrite existing sockaddr_in6
*/
sin6->sin6_scope_id = 0;
if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) {
/*
* KAME assumption: link id == interface id
*/
zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]);
if (zoneid) {
/* sanity check */
if (zoneid < 0 || if_index < zoneid)
return ENXIO;
if (ifp && ifp->if_index != zoneid)
return ENXIO;
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id = zoneid;
}
}
return 0;
}
/*
* just clear the embedded scope identifier.
*/
void
in6_clearscope(addr)
struct in6_addr *addr;
{
if (IN6_IS_SCOPE_LINKLOCAL(addr) || IN6_IS_ADDR_MC_INTFACELOCAL(addr))
addr->s6_addr16[1] = 0;
}
void
addrsel_policy_init()
{
ADDRSEL_LOCK_INIT();
init_policy_queue();
/* initialize the "last resort" policy */
bzero(&defaultaddrpolicy, sizeof(defaultaddrpolicy));
defaultaddrpolicy.label = ADDR_LABEL_NOTAPP;
}
static struct in6_addrpolicy *
lookup_addrsel_policy(key)
struct sockaddr_in6 *key;
{
struct in6_addrpolicy *match = NULL;
ADDRSEL_LOCK();
match = match_addrsel_policy(key);
if (match == NULL)
match = &defaultaddrpolicy;
else
match->use++;
ADDRSEL_UNLOCK();
return (match);
}
/*
* Subroutines to manage the address selection policy table via sysctl.
*/
struct walkarg {
struct sysctl_req *w_req;
};
static int in6_src_sysctl(SYSCTL_HANDLER_ARGS);
SYSCTL_DECL(_net_inet6_ip6);
SYSCTL_NODE(_net_inet6_ip6, IPV6CTL_ADDRCTLPOLICY, addrctlpolicy,
CTLFLAG_RD, in6_src_sysctl, "");
static int
in6_src_sysctl(SYSCTL_HANDLER_ARGS)
{
struct walkarg w;
if (req->newptr)
return EPERM;
bzero(&w, sizeof(w));
w.w_req = req;
return (walk_addrsel_policy(dump_addrsel_policyent, &w));
}
int
in6_src_ioctl(cmd, data)
u_long cmd;
caddr_t data;
{
int i;
struct in6_addrpolicy ent0;
if (cmd != SIOCAADDRCTL_POLICY && cmd != SIOCDADDRCTL_POLICY)
return (EOPNOTSUPP); /* check for safety */
ent0 = *(struct in6_addrpolicy *)data;
if (ent0.label == ADDR_LABEL_NOTAPP)
return (EINVAL);
/* check if the prefix mask is consecutive. */
if (in6_mask2len(&ent0.addrmask.sin6_addr, NULL) < 0)
return (EINVAL);
/* clear trailing garbages (if any) of the prefix address. */
for (i = 0; i < 4; i++) {
ent0.addr.sin6_addr.s6_addr32[i] &=
ent0.addrmask.sin6_addr.s6_addr32[i];
}
ent0.use = 0;
switch (cmd) {
case SIOCAADDRCTL_POLICY:
return (add_addrsel_policyent(&ent0));
case SIOCDADDRCTL_POLICY:
return (delete_addrsel_policyent(&ent0));
}
return (0); /* XXX: compromise compilers */
}
/*
* The followings are implementation of the policy table using a
* simple tail queue.
* XXX such details should be hidden.
* XXX implementation using binary tree should be more efficient.
*/
struct addrsel_policyent {
TAILQ_ENTRY(addrsel_policyent) ape_entry;
struct in6_addrpolicy ape_policy;
};
TAILQ_HEAD(addrsel_policyhead, addrsel_policyent);
struct addrsel_policyhead addrsel_policytab;
static void
init_policy_queue()
{
TAILQ_INIT(&addrsel_policytab);
}
static int
add_addrsel_policyent(newpolicy)
struct in6_addrpolicy *newpolicy;
{
struct addrsel_policyent *new, *pol;
MALLOC(new, struct addrsel_policyent *, sizeof(*new), M_IFADDR,
M_WAITOK);
ADDRSEL_LOCK();
/* duplication check */
for (pol = TAILQ_FIRST(&addrsel_policytab); pol;
pol = TAILQ_NEXT(pol, ape_entry)) {
if (SA6_ARE_ADDR_EQUAL(&newpolicy->addr,
&pol->ape_policy.addr) &&
SA6_ARE_ADDR_EQUAL(&newpolicy->addrmask,
&pol->ape_policy.addrmask)) {
ADDRSEL_UNLOCK();
FREE(new, M_IFADDR);
return (EEXIST); /* or override it? */
}
}
bzero(new, sizeof(*new));
/* XXX: should validate entry */
new->ape_policy = *newpolicy;
TAILQ_INSERT_TAIL(&addrsel_policytab, new, ape_entry);
ADDRSEL_UNLOCK();
return (0);
}
static int
delete_addrsel_policyent(key)
struct in6_addrpolicy *key;
{
struct addrsel_policyent *pol;
ADDRSEL_LOCK();
/* search for the entry in the table */
for (pol = TAILQ_FIRST(&addrsel_policytab); pol;
pol = TAILQ_NEXT(pol, ape_entry)) {
if (SA6_ARE_ADDR_EQUAL(&key->addr, &pol->ape_policy.addr) &&
SA6_ARE_ADDR_EQUAL(&key->addrmask,
&pol->ape_policy.addrmask)) {
break;
}
}
if (pol == NULL) {
ADDRSEL_UNLOCK();
return (ESRCH);
}
TAILQ_REMOVE(&addrsel_policytab, pol, ape_entry);
ADDRSEL_UNLOCK();
return (0);
}
static int
walk_addrsel_policy(callback, w)
int (*callback) __P((struct in6_addrpolicy *, void *));
void *w;
{
struct addrsel_policyent *pol;
int error = 0;
ADDRSEL_LOCK();
for (pol = TAILQ_FIRST(&addrsel_policytab); pol;
pol = TAILQ_NEXT(pol, ape_entry)) {
if ((error = (*callback)(&pol->ape_policy, w)) != 0) {
ADDRSEL_UNLOCK();
return (error);
}
}
ADDRSEL_UNLOCK();
return (error);
}
static int
dump_addrsel_policyent(pol, arg)
struct in6_addrpolicy *pol;
void *arg;
{
int error = 0;
struct walkarg *w = arg;
error = SYSCTL_OUT(w->w_req, pol, sizeof(*pol));
return (error);
}
static struct in6_addrpolicy *
match_addrsel_policy(key)
struct sockaddr_in6 *key;
{
struct addrsel_policyent *pent;
struct in6_addrpolicy *bestpol = NULL, *pol;
int matchlen, bestmatchlen = -1;
u_char *mp, *ep, *k, *p, m;
for (pent = TAILQ_FIRST(&addrsel_policytab); pent;
pent = TAILQ_NEXT(pent, ape_entry)) {
matchlen = 0;
pol = &pent->ape_policy;
mp = (u_char *)&pol->addrmask.sin6_addr;
ep = mp + 16; /* XXX: scope field? */
k = (u_char *)&key->sin6_addr;
p = (u_char *)&pol->addr.sin6_addr;
for (; mp < ep && *mp; mp++, k++, p++) {
m = *mp;
if ((*k & m) != *p)
goto next; /* not match */
if (m == 0xff) /* short cut for a typical case */
matchlen += 8;
else {
while (m >= 0x80) {
matchlen++;
m <<= 1;
}
}
}
/* matched. check if this is better than the current best. */
if (bestpol == NULL ||
matchlen > bestmatchlen) {
bestpol = pol;
bestmatchlen = matchlen;
}
next:
continue;
}
return (bestpol);
}