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/*-
* Copyright (c) 2015
* Alexander V. Chernikov <melifaro@FreeBSD.org>
*
* 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 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_route.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/rmlock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/kernel.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/route/route_ctl.h>
#include <net/route/route_var.h>
#include <net/route/nhop.h>
#include <net/toeplitz.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip_mroute.h>
#include <netinet/ip6.h>
#include <netinet6/in6_fib.h>
#include <netinet6/in6_var.h>
#include <netinet6/nd6.h>
#include <netinet6/scope6_var.h>
#include <net/if_types.h>
#ifdef INET6
CHK_STRUCT_ROUTE_COMPAT(struct route_in6, ro_dst);
#ifdef ROUTE_MPATH
struct _hash_5tuple_ipv6 {
struct in6_addr src;
struct in6_addr dst;
unsigned short src_port;
unsigned short dst_port;
char proto;
char spare[3];
};
_Static_assert(sizeof(struct _hash_5tuple_ipv6) == 40,
"_hash_5tuple_ipv6 size is wrong");
uint32_t
fib6_calc_software_hash(const struct in6_addr *src, const struct in6_addr *dst,
unsigned short src_port, unsigned short dst_port, char proto,
uint32_t *phashtype)
{
struct _hash_5tuple_ipv6 data;
data.src = *src;
data.dst = *dst;
data.src_port = src_port;
data.dst_port = dst_port;
data.proto = proto;
data.spare[0] = data.spare[1] = data.spare[2] = 0;
*phashtype = M_HASHTYPE_OPAQUE_HASH;
return (toeplitz_hash(MPATH_ENTROPY_KEY_LEN, mpath_entropy_key,
sizeof(data), (uint8_t *)&data));
}
#endif
/*
* Looks up path in fib @fibnum specified by @dst.
* Assumes scope is deembedded and provided in @scopeid.
*
* Returns path nexthop on success. Nexthop is safe to use
* within the current network epoch. If longer lifetime is required,
* one needs to pass NHR_REF as a flag. This will return referenced
* nexthop.
*/
struct nhop_object *
fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid, uint32_t flags, uint32_t flowid)
{
RIB_RLOCK_TRACKER;
struct rib_head *rh;
struct radix_node *rn;
struct nhop_object *nh;
KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum"));
rh = rt_tables_get_rnh(fibnum, AF_INET6);
if (rh == NULL)
return (NULL);
struct sockaddr_in6 sin6 = {
.sin6_len = sizeof(struct sockaddr_in6),
.sin6_addr = *dst6,
};
/* Assume scopeid is valid and embed it directly */
if (IN6_IS_SCOPE_LINKLOCAL(dst6))
sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
RIB_RLOCK(rh);
rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
nh = nhop_select((RNTORT(rn))->rt_nhop, flowid);
/* Ensure route & ifp is UP */
if (RT_LINK_IS_UP(nh->nh_ifp)) {
if (flags & NHR_REF)
nhop_ref_object(nh);
RIB_RUNLOCK(rh);
return (nh);
}
}
RIB_RUNLOCK(rh);
RTSTAT_INC(rts_unreach);
return (NULL);
}
inline static int
check_urpf_nhop(const struct nhop_object *nh, uint32_t flags,
const struct ifnet *src_if)
{
if (src_if != NULL && nh->nh_aifp == src_if) {
return (1);
}
if (src_if == NULL) {
if ((flags & NHR_NODEFAULT) == 0)
return (1);
else if ((nh->nh_flags & NHF_DEFAULT) == 0)
return (1);
}
return (0);
}
static int
check_urpf(struct nhop_object *nh, uint32_t flags,
const struct ifnet *src_if)
{
#ifdef ROUTE_MPATH
if (NH_IS_NHGRP(nh)) {
struct weightened_nhop *wn;
uint32_t num_nhops;
wn = nhgrp_get_nhops((struct nhgrp_object *)nh, &num_nhops);
for (int i = 0; i < num_nhops; i++) {
if (check_urpf_nhop(wn[i].nh, flags, src_if) != 0)
return (1);
}
return (0);
} else
#endif
return (check_urpf_nhop(nh, flags, src_if));
}
static struct nhop_object *
lookup_nhop(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid)
{
RIB_RLOCK_TRACKER;
struct rib_head *rh;
struct radix_node *rn;
struct nhop_object *nh;
KASSERT((fibnum < rt_numfibs), ("fib6_check_urpf: bad fibnum"));
rh = rt_tables_get_rnh(fibnum, AF_INET6);
if (rh == NULL)
return (NULL);
/* Prepare lookup key */
struct sockaddr_in6 sin6 = {
.sin6_len = sizeof(struct sockaddr_in6),
.sin6_addr = *dst6,
};
/* Assume scopeid is valid and embed it directly */
if (IN6_IS_SCOPE_LINKLOCAL(dst6))
sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
nh = NULL;
RIB_RLOCK(rh);
rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0))
nh = RNTORT(rn)->rt_nhop;
RIB_RUNLOCK(rh);
return (nh);
}
/*
* Performs reverse path forwarding lookup.
* If @src_if is non-zero, verifies that at least 1 path goes via
* this interface.
* If @src_if is zero, verifies that route exist.
* if @flags contains NHR_NOTDEFAULT, do not consider default route.
*
* Returns 1 if route matching conditions is found, 0 otherwise.
*/
int
fib6_check_urpf(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid, uint32_t flags, const struct ifnet *src_if)
{
struct nhop_object *nh;
nh = lookup_nhop(fibnum, dst6, scopeid);
if (nh != NULL)
return (check_urpf(nh, flags, src_if));
return (0);
}
/*
* Function returning prefix match data along with the nexthop data.
* Intended to be used by the control plane code.
* Supported flags:
* NHR_UNLOCKED: do not lock radix during lookup.
* Returns pointer to rtentry and raw nexthop in @rnd. Both rtentry
* and nexthop are safe to use within current epoch. Note:
* Note: rnd_nhop can actually be the nexthop group.
*/
struct rtentry *
fib6_lookup_rt(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid, uint32_t flags, struct route_nhop_data *rnd)
{
RIB_RLOCK_TRACKER;
struct rib_head *rh;
struct radix_node *rn;
struct rtentry *rt;
KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum"));
rh = rt_tables_get_rnh(fibnum, AF_INET6);
if (rh == NULL)
return (NULL);
struct sockaddr_in6 sin6 = {
.sin6_len = sizeof(struct sockaddr_in6),
.sin6_addr = *dst6,
};
/* Assume scopeid is valid and embed it directly */
if (IN6_IS_SCOPE_LINKLOCAL(dst6))
sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff);
rt = NULL;
if (!(flags & NHR_UNLOCKED))
RIB_RLOCK(rh);
rn = rh->rnh_matchaddr((void *)&sin6, &rh->head);
if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) {
rt = (struct rtentry *)rn;
rnd->rnd_nhop = rt->rt_nhop;
rnd->rnd_weight = rt->rt_weight;
}
if (!(flags & NHR_UNLOCKED))
RIB_RUNLOCK(rh);
return (rt);
}
struct nhop_object *
fib6_lookup_debugnet(uint32_t fibnum, const struct in6_addr *dst6,
uint32_t scopeid, uint32_t flags)
{
struct rtentry *rt;
struct route_nhop_data rnd;
rt = fib6_lookup_rt(fibnum, dst6, scopeid, NHR_UNLOCKED, &rnd);
if (rt != NULL) {
struct nhop_object *nh = nhop_select(rnd.rnd_nhop, 0);
/* Ensure route & ifp is UP */
if (RT_LINK_IS_UP(nh->nh_ifp))
return (nh);
}
return (NULL);
}
#endif
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