diff options
Diffstat (limited to 'net/ipv6/route.c')
| -rw-r--r-- | net/ipv6/route.c | 6593 |
1 files changed, 5194 insertions, 1399 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index a8c891aa2464..aee6a10b112a 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1,14 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Linux INET6 implementation * FIB front-end. * * Authors: * Pedro Roque <roque@di.fc.ul.pt> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ /* Changes: @@ -44,6 +40,8 @@ #include <linux/seq_file.h> #include <linux/nsproxy.h> #include <linux/slab.h> +#include <linux/jhash.h> +#include <linux/siphash.h> #include <net/net_namespace.h> #include <net/snmp.h> #include <net/ipv6.h> @@ -54,89 +52,152 @@ #include <net/tcp.h> #include <linux/rtnetlink.h> #include <net/dst.h> +#include <net/dst_metadata.h> #include <net/xfrm.h> #include <net/netevent.h> #include <net/netlink.h> -#include <net/nexthop.h> - -#include <asm/uaccess.h> +#include <net/rtnh.h> +#include <net/lwtunnel.h> +#include <net/ip_tunnels.h> +#include <net/l3mdev.h> +#include <net/ip.h> +#include <linux/uaccess.h> +#include <linux/btf_ids.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif +static int ip6_rt_type_to_error(u8 fib6_type); + +#define CREATE_TRACE_POINTS +#include <trace/events/fib6.h> +EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup); +#undef CREATE_TRACE_POINTS + enum rt6_nud_state { - RT6_NUD_FAIL_HARD = -2, - RT6_NUD_FAIL_SOFT = -1, + RT6_NUD_FAIL_HARD = -3, + RT6_NUD_FAIL_PROBE = -2, + RT6_NUD_FAIL_DO_RR = -1, RT6_NUD_SUCCEED = 1 }; -static struct rt6_info *ip6_rt_copy(struct rt6_info *ort, - const struct in6_addr *dest); -static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); +INDIRECT_CALLABLE_SCOPE +struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); static unsigned int ip6_default_advmss(const struct dst_entry *dst); -static unsigned int ip6_mtu(const struct dst_entry *dst); -static struct dst_entry *ip6_negative_advice(struct dst_entry *); +INDIRECT_CALLABLE_SCOPE +unsigned int ip6_mtu(const struct dst_entry *dst); +static void ip6_negative_advice(struct sock *sk, + struct dst_entry *dst); static void ip6_dst_destroy(struct dst_entry *); static void ip6_dst_ifdown(struct dst_entry *, - struct net_device *dev, int how); -static int ip6_dst_gc(struct dst_ops *ops); + struct net_device *dev); +static void ip6_dst_gc(struct dst_ops *ops); static int ip6_pkt_discard(struct sk_buff *skb); -static int ip6_pkt_discard_out(struct sk_buff *skb); +static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb); +static int ip6_pkt_prohibit(struct sk_buff *skb); +static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb); static void ip6_link_failure(struct sk_buff *skb); static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, - struct sk_buff *skb, u32 mtu); + struct sk_buff *skb, u32 mtu, + bool confirm_neigh); static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb); -static int rt6_score_route(struct rt6_info *rt, int oif, int strict); +static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif, + int strict); +static size_t rt6_nlmsg_size(struct fib6_info *f6i); +static int rt6_fill_node(struct net *net, struct sk_buff *skb, + struct fib6_info *rt, struct dst_entry *dst, + struct in6_addr *dest, struct in6_addr *src, + int iif, int type, u32 portid, u32 seq, + unsigned int flags); +static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res, + const struct in6_addr *daddr, + const struct in6_addr *saddr); #ifdef CONFIG_IPV6_ROUTE_INFO -static struct rt6_info *rt6_add_route_info(struct net *net, +static struct fib6_info *rt6_add_route_info(struct net *net, const struct in6_addr *prefix, int prefixlen, - const struct in6_addr *gwaddr, int ifindex, + const struct in6_addr *gwaddr, + struct net_device *dev, unsigned int pref); -static struct rt6_info *rt6_get_route_info(struct net *net, +static struct fib6_info *rt6_get_route_info(struct net *net, const struct in6_addr *prefix, int prefixlen, - const struct in6_addr *gwaddr, int ifindex); + const struct in6_addr *gwaddr, + struct net_device *dev); #endif -static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old) +struct uncached_list { + spinlock_t lock; + struct list_head head; +}; + +static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list); + +void rt6_uncached_list_add(struct rt6_info *rt) { - struct rt6_info *rt = (struct rt6_info *) dst; - struct inet_peer *peer; - u32 *p = NULL; + struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list); - if (!(rt->dst.flags & DST_HOST)) - return NULL; + rt->dst.rt_uncached_list = ul; + + spin_lock_bh(&ul->lock); + list_add_tail(&rt->dst.rt_uncached, &ul->head); + spin_unlock_bh(&ul->lock); +} + +void rt6_uncached_list_del(struct rt6_info *rt) +{ + if (!list_empty(&rt->dst.rt_uncached)) { + struct uncached_list *ul = rt->dst.rt_uncached_list; + + spin_lock_bh(&ul->lock); + list_del_init(&rt->dst.rt_uncached); + spin_unlock_bh(&ul->lock); + } +} + +static void rt6_uncached_list_flush_dev(struct net_device *dev) +{ + int cpu; - peer = rt6_get_peer_create(rt); - if (peer) { - u32 *old_p = __DST_METRICS_PTR(old); - unsigned long prev, new; + for_each_possible_cpu(cpu) { + struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu); + struct rt6_info *rt, *safe; - p = peer->metrics; - if (inet_metrics_new(peer)) - memcpy(p, old_p, sizeof(u32) * RTAX_MAX); + if (list_empty(&ul->head)) + continue; + + spin_lock_bh(&ul->lock); + list_for_each_entry_safe(rt, safe, &ul->head, dst.rt_uncached) { + struct inet6_dev *rt_idev = rt->rt6i_idev; + struct net_device *rt_dev = rt->dst.dev; + bool handled = false; - new = (unsigned long) p; - prev = cmpxchg(&dst->_metrics, old, new); + if (rt_idev && rt_idev->dev == dev) { + rt->rt6i_idev = in6_dev_get(blackhole_netdev); + in6_dev_put(rt_idev); + handled = true; + } - if (prev != old) { - p = __DST_METRICS_PTR(prev); - if (prev & DST_METRICS_READ_ONLY) - p = NULL; + if (rt_dev == dev) { + rt->dst.dev = blackhole_netdev; + netdev_ref_replace(rt_dev, blackhole_netdev, + &rt->dst.dev_tracker, + GFP_ATOMIC); + handled = true; + } + if (handled) + list_del_init(&rt->dst.rt_uncached); } + spin_unlock_bh(&ul->lock); } - return p; } -static inline const void *choose_neigh_daddr(struct rt6_info *rt, +static inline const void *choose_neigh_daddr(const struct in6_addr *p, struct sk_buff *skb, const void *daddr) { - struct in6_addr *p = &rt->rt6i_gateway; - if (!ipv6_addr_any(p)) return (const void *) p; else if (skb) @@ -144,29 +205,55 @@ static inline const void *choose_neigh_daddr(struct rt6_info *rt, return daddr; } -static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst, - struct sk_buff *skb, - const void *daddr) +struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw, + struct net_device *dev, + struct sk_buff *skb, + const void *daddr) { - struct rt6_info *rt = (struct rt6_info *) dst; struct neighbour *n; - daddr = choose_neigh_daddr(rt, skb, daddr); - n = __ipv6_neigh_lookup(dst->dev, daddr); + daddr = choose_neigh_daddr(gw, skb, daddr); + n = __ipv6_neigh_lookup(dev, daddr); if (n) return n; - return neigh_create(&nd_tbl, daddr, dst->dev); + + n = neigh_create(&nd_tbl, daddr, dev); + return IS_ERR(n) ? NULL : n; +} + +static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst, + struct sk_buff *skb, + const void *daddr) +{ + const struct rt6_info *rt = dst_rt6_info(dst); + + return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any), + dst_dev(dst), skb, daddr); +} + +static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr) +{ + const struct rt6_info *rt = dst_rt6_info(dst); + struct net_device *dev = dst_dev(dst); + + daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr); + if (!daddr) + return; + if (dev->flags & (IFF_NOARP | IFF_LOOPBACK)) + return; + if (ipv6_addr_is_multicast((const struct in6_addr *)daddr)) + return; + __ipv6_confirm_neigh(dev, daddr); } static struct dst_ops ip6_dst_ops_template = { .family = AF_INET6, - .protocol = cpu_to_be16(ETH_P_IPV6), .gc = ip6_dst_gc, .gc_thresh = 1024, .check = ip6_dst_check, .default_advmss = ip6_default_advmss, .mtu = ip6_mtu, - .cow_metrics = ipv6_cow_metrics, + .cow_metrics = dst_cow_metrics_generic, .destroy = ip6_dst_destroy, .ifdown = ip6_dst_ifdown, .negative_advice = ip6_negative_advice, @@ -174,52 +261,38 @@ static struct dst_ops ip6_dst_ops_template = { .update_pmtu = ip6_rt_update_pmtu, .redirect = rt6_do_redirect, .local_out = __ip6_local_out, - .neigh_lookup = ip6_neigh_lookup, + .neigh_lookup = ip6_dst_neigh_lookup, + .confirm_neigh = ip6_confirm_neigh, }; -static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst) -{ - unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); - - return mtu ? : dst->dev->mtu; -} - -static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk, - struct sk_buff *skb, u32 mtu) -{ -} - -static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk, - struct sk_buff *skb) -{ -} - -static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst, - unsigned long old) -{ - return NULL; -} - static struct dst_ops ip6_dst_blackhole_ops = { - .family = AF_INET6, - .protocol = cpu_to_be16(ETH_P_IPV6), - .destroy = ip6_dst_destroy, - .check = ip6_dst_check, - .mtu = ip6_blackhole_mtu, - .default_advmss = ip6_default_advmss, - .update_pmtu = ip6_rt_blackhole_update_pmtu, - .redirect = ip6_rt_blackhole_redirect, - .cow_metrics = ip6_rt_blackhole_cow_metrics, - .neigh_lookup = ip6_neigh_lookup, + .family = AF_INET6, + .default_advmss = ip6_default_advmss, + .neigh_lookup = ip6_dst_neigh_lookup, + .check = ip6_dst_check, + .destroy = ip6_dst_destroy, + .cow_metrics = dst_cow_metrics_generic, + .update_pmtu = dst_blackhole_update_pmtu, + .redirect = dst_blackhole_redirect, + .mtu = dst_blackhole_mtu, }; static const u32 ip6_template_metrics[RTAX_MAX] = { [RTAX_HOPLIMIT - 1] = 0, }; +static const struct fib6_info fib6_null_entry_template = { + .fib6_flags = (RTF_REJECT | RTF_NONEXTHOP), + .fib6_protocol = RTPROT_KERNEL, + .fib6_metric = ~(u32)0, + .fib6_ref = REFCOUNT_INIT(1), + .fib6_type = RTN_UNREACHABLE, + .fib6_metrics = (struct dst_metrics *)&dst_default_metrics, +}; + static const struct rt6_info ip6_null_entry_template = { .dst = { - .__refcnt = ATOMIC_INIT(1), + .__rcuref = RCUREF_INIT(1), .__use = 1, .obsolete = DST_OBSOLETE_FORCE_CHK, .error = -ENETUNREACH, @@ -227,19 +300,13 @@ static const struct rt6_info ip6_null_entry_template = { .output = ip6_pkt_discard_out, }, .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), - .rt6i_protocol = RTPROT_KERNEL, - .rt6i_metric = ~(u32) 0, - .rt6i_ref = ATOMIC_INIT(1), }; #ifdef CONFIG_IPV6_MULTIPLE_TABLES -static int ip6_pkt_prohibit(struct sk_buff *skb); -static int ip6_pkt_prohibit_out(struct sk_buff *skb); - static const struct rt6_info ip6_prohibit_entry_template = { .dst = { - .__refcnt = ATOMIC_INIT(1), + .__rcuref = RCUREF_INIT(1), .__use = 1, .obsolete = DST_OBSOLETE_FORCE_CHK, .error = -EACCES, @@ -247,239 +314,348 @@ static const struct rt6_info ip6_prohibit_entry_template = { .output = ip6_pkt_prohibit_out, }, .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), - .rt6i_protocol = RTPROT_KERNEL, - .rt6i_metric = ~(u32) 0, - .rt6i_ref = ATOMIC_INIT(1), }; static const struct rt6_info ip6_blk_hole_entry_template = { .dst = { - .__refcnt = ATOMIC_INIT(1), + .__rcuref = RCUREF_INIT(1), .__use = 1, .obsolete = DST_OBSOLETE_FORCE_CHK, .error = -EINVAL, .input = dst_discard, - .output = dst_discard, + .output = dst_discard_out, }, .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), - .rt6i_protocol = RTPROT_KERNEL, - .rt6i_metric = ~(u32) 0, - .rt6i_ref = ATOMIC_INIT(1), }; #endif +static void rt6_info_init(struct rt6_info *rt) +{ + memset_after(rt, 0, dst); +} + /* allocate dst with ip6_dst_ops */ -static inline struct rt6_info *ip6_dst_alloc(struct net *net, - struct net_device *dev, - int flags, - struct fib6_table *table) +struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, + int flags) { struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev, - 0, DST_OBSOLETE_FORCE_CHK, flags); + DST_OBSOLETE_FORCE_CHK, flags); if (rt) { - struct dst_entry *dst = &rt->dst; - - memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst)); - rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers); - rt->rt6i_genid = rt_genid(net); - INIT_LIST_HEAD(&rt->rt6i_siblings); - rt->rt6i_nsiblings = 0; + rt6_info_init(rt); + atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc); } + return rt; } +EXPORT_SYMBOL(ip6_dst_alloc); static void ip6_dst_destroy(struct dst_entry *dst) { - struct rt6_info *rt = (struct rt6_info *)dst; - struct inet6_dev *idev = rt->rt6i_idev; - struct dst_entry *from = dst->from; + struct rt6_info *rt = dst_rt6_info(dst); + struct fib6_info *from; + struct inet6_dev *idev; - if (!(rt->dst.flags & DST_HOST)) - dst_destroy_metrics_generic(dst); + ip_dst_metrics_put(dst); + rt6_uncached_list_del(rt); + idev = rt->rt6i_idev; if (idev) { rt->rt6i_idev = NULL; in6_dev_put(idev); } - dst->from = NULL; - dst_release(from); - - if (rt6_has_peer(rt)) { - struct inet_peer *peer = rt6_peer_ptr(rt); - inet_putpeer(peer); - } + from = unrcu_pointer(xchg(&rt->from, NULL)); + fib6_info_release(from); } -void rt6_bind_peer(struct rt6_info *rt, int create) +static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev) { - struct inet_peer_base *base; - struct inet_peer *peer; + struct rt6_info *rt = dst_rt6_info(dst); + struct inet6_dev *idev = rt->rt6i_idev; + struct fib6_info *from; - base = inetpeer_base_ptr(rt->_rt6i_peer); - if (!base) - return; + if (idev && idev->dev != blackhole_netdev) { + struct inet6_dev *blackhole_idev = in6_dev_get(blackhole_netdev); - peer = inet_getpeer_v6(base, &rt->rt6i_dst.addr, create); - if (peer) { - if (!rt6_set_peer(rt, peer)) - inet_putpeer(peer); + if (blackhole_idev) { + rt->rt6i_idev = blackhole_idev; + in6_dev_put(idev); + } } + from = unrcu_pointer(xchg(&rt->from, NULL)); + fib6_info_release(from); } -static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, - int how) +static bool __rt6_check_expired(const struct rt6_info *rt) { - struct rt6_info *rt = (struct rt6_info *)dst; - struct inet6_dev *idev = rt->rt6i_idev; - struct net_device *loopback_dev = - dev_net(dev)->loopback_dev; - - if (dev != loopback_dev) { - if (idev && idev->dev == dev) { - struct inet6_dev *loopback_idev = - in6_dev_get(loopback_dev); - if (loopback_idev) { - rt->rt6i_idev = loopback_idev; - in6_dev_put(idev); - } - } - } + if (rt->rt6i_flags & RTF_EXPIRES) + return time_after(jiffies, READ_ONCE(rt->dst.expires)); + return false; } static bool rt6_check_expired(const struct rt6_info *rt) { + struct fib6_info *from; + + from = rcu_dereference(rt->from); + if (rt->rt6i_flags & RTF_EXPIRES) { - if (time_after(jiffies, rt->dst.expires)) + if (time_after(jiffies, READ_ONCE(rt->dst.expires))) return true; - } else if (rt->dst.from) { - return rt6_check_expired((struct rt6_info *) rt->dst.from); + } else if (from) { + return READ_ONCE(rt->dst.obsolete) != DST_OBSOLETE_FORCE_CHK || + fib6_check_expired(from); } return false; } -static bool rt6_need_strict(const struct in6_addr *daddr) +static struct fib6_info * +rt6_multipath_first_sibling_rcu(const struct fib6_info *rt) { - return ipv6_addr_type(daddr) & - (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK); + struct fib6_info *iter; + struct fib6_node *fn; + + fn = rcu_dereference(rt->fib6_node); + if (!fn) + goto out; + iter = rcu_dereference(fn->leaf); + if (!iter) + goto out; + + while (iter) { + if (iter->fib6_metric == rt->fib6_metric && + rt6_qualify_for_ecmp(iter)) + return iter; + iter = rcu_dereference(iter->fib6_next); + } + +out: + return NULL; } -/* Multipath route selection: - * Hash based function using packet header and flowlabel. - * Adapted from fib_info_hashfn() - */ -static int rt6_info_hash_nhsfn(unsigned int candidate_count, - const struct flowi6 *fl6) +void fib6_select_path(const struct net *net, struct fib6_result *res, + struct flowi6 *fl6, int oif, bool have_oif_match, + const struct sk_buff *skb, int strict) { - unsigned int val = fl6->flowi6_proto; + struct fib6_info *first, *match = res->f6i; + struct fib6_info *sibling; + int hash; - val ^= ipv6_addr_hash(&fl6->daddr); - val ^= ipv6_addr_hash(&fl6->saddr); + if (!match->nh && (!match->fib6_nsiblings || have_oif_match)) + goto out; - /* Work only if this not encapsulated */ - switch (fl6->flowi6_proto) { - case IPPROTO_UDP: - case IPPROTO_TCP: - case IPPROTO_SCTP: - val ^= (__force u16)fl6->fl6_sport; - val ^= (__force u16)fl6->fl6_dport; - break; + if (match->nh && have_oif_match && res->nh) + return; + + if (skb) + IP6CB(skb)->flags |= IP6SKB_MULTIPATH; + + /* We might have already computed the hash for ICMPv6 errors. In such + * case it will always be non-zero. Otherwise now is the time to do it. + */ + if (!fl6->mp_hash && + (!match->nh || nexthop_is_multipath(match->nh))) + fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL); + + if (unlikely(match->nh)) { + nexthop_path_fib6_result(res, fl6->mp_hash); + return; + } + + first = rt6_multipath_first_sibling_rcu(match); + if (!first) + goto out; - case IPPROTO_ICMPV6: - val ^= (__force u16)fl6->fl6_icmp_type; - val ^= (__force u16)fl6->fl6_icmp_code; + hash = fl6->mp_hash; + if (hash <= atomic_read(&first->fib6_nh->fib_nh_upper_bound)) { + if (rt6_score_route(first->fib6_nh, first->fib6_flags, oif, + strict) >= 0) + match = first; + goto out; + } + + list_for_each_entry_rcu(sibling, &first->fib6_siblings, + fib6_siblings) { + const struct fib6_nh *nh = sibling->fib6_nh; + int nh_upper_bound; + + nh_upper_bound = atomic_read(&nh->fib_nh_upper_bound); + if (hash > nh_upper_bound) + continue; + if (rt6_score_route(nh, sibling->fib6_flags, oif, strict) < 0) + break; + match = sibling; break; } - /* RFC6438 recommands to use flowlabel */ - val ^= (__force u32)fl6->flowlabel; - /* Perhaps, we need to tune, this function? */ - val = val ^ (val >> 7) ^ (val >> 12); - return val % candidate_count; +out: + res->f6i = match; + res->nh = match->fib6_nh; } -static struct rt6_info *rt6_multipath_select(struct rt6_info *match, - struct flowi6 *fl6, int oif, - int strict) +/* + * Route lookup. rcu_read_lock() should be held. + */ + +static bool __rt6_device_match(struct net *net, const struct fib6_nh *nh, + const struct in6_addr *saddr, int oif, int flags) { - struct rt6_info *sibling, *next_sibling; - int route_choosen; + const struct net_device *dev; - route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6); - /* Don't change the route, if route_choosen == 0 - * (siblings does not include ourself) - */ - if (route_choosen) - list_for_each_entry_safe(sibling, next_sibling, - &match->rt6i_siblings, rt6i_siblings) { - route_choosen--; - if (route_choosen == 0) { - if (rt6_score_route(sibling, oif, strict) < 0) - break; - match = sibling; - break; - } - } - return match; + if (nh->fib_nh_flags & RTNH_F_DEAD) + return false; + + dev = nh->fib_nh_dev; + if (oif) { + if (dev->ifindex == oif) + return true; + } else { + if (ipv6_chk_addr(net, saddr, dev, + flags & RT6_LOOKUP_F_IFACE)) + return true; + } + + return false; } -/* - * Route lookup. Any table->tb6_lock is implied. - */ +struct fib6_nh_dm_arg { + struct net *net; + const struct in6_addr *saddr; + int oif; + int flags; + struct fib6_nh *nh; +}; -static inline struct rt6_info *rt6_device_match(struct net *net, - struct rt6_info *rt, - const struct in6_addr *saddr, - int oif, - int flags) +static int __rt6_nh_dev_match(struct fib6_nh *nh, void *_arg) { - struct rt6_info *local = NULL; - struct rt6_info *sprt; + struct fib6_nh_dm_arg *arg = _arg; - if (!oif && ipv6_addr_any(saddr)) - goto out; + arg->nh = nh; + return __rt6_device_match(arg->net, nh, arg->saddr, arg->oif, + arg->flags); +} - for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) { - struct net_device *dev = sprt->dst.dev; - - if (oif) { - if (dev->ifindex == oif) - return sprt; - if (dev->flags & IFF_LOOPBACK) { - if (!sprt->rt6i_idev || - sprt->rt6i_idev->dev->ifindex != oif) { - if (flags & RT6_LOOKUP_F_IFACE && oif) - continue; - if (local && (!oif || - local->rt6i_idev->dev->ifindex == oif)) - continue; - } - local = sprt; - } +/* returns fib6_nh from nexthop or NULL */ +static struct fib6_nh *rt6_nh_dev_match(struct net *net, struct nexthop *nh, + struct fib6_result *res, + const struct in6_addr *saddr, + int oif, int flags) +{ + struct fib6_nh_dm_arg arg = { + .net = net, + .saddr = saddr, + .oif = oif, + .flags = flags, + }; + + if (nexthop_is_blackhole(nh)) + return NULL; + + if (nexthop_for_each_fib6_nh(nh, __rt6_nh_dev_match, &arg)) + return arg.nh; + + return NULL; +} + +static void rt6_device_match(struct net *net, struct fib6_result *res, + const struct in6_addr *saddr, int oif, int flags) +{ + struct fib6_info *f6i = res->f6i; + struct fib6_info *spf6i; + struct fib6_nh *nh; + + if (!oif && ipv6_addr_any(saddr)) { + if (unlikely(f6i->nh)) { + nh = nexthop_fib6_nh(f6i->nh); + if (nexthop_is_blackhole(f6i->nh)) + goto out_blackhole; } else { - if (ipv6_chk_addr(net, saddr, dev, - flags & RT6_LOOKUP_F_IFACE)) - return sprt; + nh = f6i->fib6_nh; } + if (!(nh->fib_nh_flags & RTNH_F_DEAD)) + goto out; } - if (oif) { - if (local) - return local; + for (spf6i = f6i; spf6i; spf6i = rcu_dereference(spf6i->fib6_next)) { + bool matched = false; - if (flags & RT6_LOOKUP_F_IFACE) - return net->ipv6.ip6_null_entry; + if (unlikely(spf6i->nh)) { + nh = rt6_nh_dev_match(net, spf6i->nh, res, saddr, + oif, flags); + if (nh) + matched = true; + } else { + nh = spf6i->fib6_nh; + if (__rt6_device_match(net, nh, saddr, oif, flags)) + matched = true; + } + if (matched) { + res->f6i = spf6i; + goto out; + } + } + + if (oif && flags & RT6_LOOKUP_F_IFACE) { + res->f6i = net->ipv6.fib6_null_entry; + nh = res->f6i->fib6_nh; + goto out; + } + + if (unlikely(f6i->nh)) { + nh = nexthop_fib6_nh(f6i->nh); + if (nexthop_is_blackhole(f6i->nh)) + goto out_blackhole; + } else { + nh = f6i->fib6_nh; + } + + if (nh->fib_nh_flags & RTNH_F_DEAD) { + res->f6i = net->ipv6.fib6_null_entry; + nh = res->f6i->fib6_nh; } out: - return rt; + res->nh = nh; + res->fib6_type = res->f6i->fib6_type; + res->fib6_flags = res->f6i->fib6_flags; + return; + +out_blackhole: + res->fib6_flags |= RTF_REJECT; + res->fib6_type = RTN_BLACKHOLE; + res->nh = nh; } #ifdef CONFIG_IPV6_ROUTER_PREF -static void rt6_probe(struct rt6_info *rt) +struct __rt6_probe_work { + struct work_struct work; + struct in6_addr target; + struct net_device *dev; + netdevice_tracker dev_tracker; +}; + +static void rt6_probe_deferred(struct work_struct *w) +{ + struct in6_addr mcaddr; + struct __rt6_probe_work *work = + container_of(w, struct __rt6_probe_work, work); + + addrconf_addr_solict_mult(&work->target, &mcaddr); + ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0); + netdev_put(work->dev, &work->dev_tracker); + kfree(work); +} + +static void rt6_probe(struct fib6_nh *fib6_nh) { + struct __rt6_probe_work *work = NULL; + const struct in6_addr *nh_gw; + unsigned long last_probe; struct neighbour *neigh; + struct net_device *dev; + struct inet6_dev *idev; + /* * Okay, this does not seem to be appropriate * for now, however, we need to check if it @@ -488,37 +664,52 @@ static void rt6_probe(struct rt6_info *rt) * Router Reachability Probe MUST be rate-limited * to no more than one per minute. */ - if (!rt || !(rt->rt6i_flags & RTF_GATEWAY)) + if (!fib6_nh->fib_nh_gw_family) return; - rcu_read_lock_bh(); - neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway); + + nh_gw = &fib6_nh->fib_nh_gw6; + dev = fib6_nh->fib_nh_dev; + rcu_read_lock(); + last_probe = READ_ONCE(fib6_nh->last_probe); + idev = __in6_dev_get(dev); + if (!idev) + goto out; + neigh = __ipv6_neigh_lookup_noref(dev, nh_gw); if (neigh) { - write_lock(&neigh->lock); - if (neigh->nud_state & NUD_VALID) + if (READ_ONCE(neigh->nud_state) & NUD_VALID) goto out; - } - - if (!neigh || - time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) { - struct in6_addr mcaddr; - struct in6_addr *target; - if (neigh) { - neigh->updated = jiffies; - write_unlock(&neigh->lock); + write_lock_bh(&neigh->lock); + if (!(neigh->nud_state & NUD_VALID) && + time_after(jiffies, + neigh->updated + + READ_ONCE(idev->cnf.rtr_probe_interval))) { + work = kmalloc(sizeof(*work), GFP_ATOMIC); + if (work) + __neigh_set_probe_once(neigh); } + write_unlock_bh(&neigh->lock); + } else if (time_after(jiffies, last_probe + + READ_ONCE(idev->cnf.rtr_probe_interval))) { + work = kmalloc(sizeof(*work), GFP_ATOMIC); + } - target = (struct in6_addr *)&rt->rt6i_gateway; - addrconf_addr_solict_mult(target, &mcaddr); - ndisc_send_ns(rt->dst.dev, NULL, target, &mcaddr, NULL); + if (!work || cmpxchg(&fib6_nh->last_probe, + last_probe, jiffies) != last_probe) { + kfree(work); } else { -out: - write_unlock(&neigh->lock); + INIT_WORK(&work->work, rt6_probe_deferred); + work->target = *nh_gw; + netdev_hold(dev, &work->dev_tracker, GFP_ATOMIC); + work->dev = dev; + schedule_work(&work->work); } - rcu_read_unlock_bh(); + +out: + rcu_read_unlock(); } #else -static inline void rt6_probe(struct rt6_info *rt) +static inline void rt6_probe(struct fib6_nh *fib6_nh) { } #endif @@ -526,140 +717,249 @@ static inline void rt6_probe(struct rt6_info *rt) /* * Default Router Selection (RFC 2461 6.3.6) */ -static inline int rt6_check_dev(struct rt6_info *rt, int oif) +static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh) { - struct net_device *dev = rt->dst.dev; - if (!oif || dev->ifindex == oif) - return 2; - if ((dev->flags & IFF_LOOPBACK) && - rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif) - return 1; - return 0; -} - -static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt) -{ - struct neighbour *neigh; enum rt6_nud_state ret = RT6_NUD_FAIL_HARD; + struct neighbour *neigh; - if (rt->rt6i_flags & RTF_NONEXTHOP || - !(rt->rt6i_flags & RTF_GATEWAY)) - return RT6_NUD_SUCCEED; - - rcu_read_lock_bh(); - neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway); + rcu_read_lock(); + neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev, + &fib6_nh->fib_nh_gw6); if (neigh) { - read_lock(&neigh->lock); - if (neigh->nud_state & NUD_VALID) + u8 nud_state = READ_ONCE(neigh->nud_state); + + if (nud_state & NUD_VALID) ret = RT6_NUD_SUCCEED; #ifdef CONFIG_IPV6_ROUTER_PREF - else if (!(neigh->nud_state & NUD_FAILED)) + else if (!(nud_state & NUD_FAILED)) ret = RT6_NUD_SUCCEED; + else + ret = RT6_NUD_FAIL_PROBE; #endif - read_unlock(&neigh->lock); } else { ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ? - RT6_NUD_SUCCEED : RT6_NUD_FAIL_SOFT; + RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR; } - rcu_read_unlock_bh(); + rcu_read_unlock(); return ret; } -static int rt6_score_route(struct rt6_info *rt, int oif, +static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif, int strict) { - int m; + int m = 0; + + if (!oif || nh->fib_nh_dev->ifindex == oif) + m = 2; - m = rt6_check_dev(rt, oif); if (!m && (strict & RT6_LOOKUP_F_IFACE)) return RT6_NUD_FAIL_HARD; #ifdef CONFIG_IPV6_ROUTER_PREF - m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2; + m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(fib6_flags)) << 2; #endif - if (strict & RT6_LOOKUP_F_REACHABLE) { - int n = rt6_check_neigh(rt); + if ((strict & RT6_LOOKUP_F_REACHABLE) && + !(fib6_flags & RTF_NONEXTHOP) && nh->fib_nh_gw_family) { + int n = rt6_check_neigh(nh); if (n < 0) return n; } return m; } -static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, - int *mpri, struct rt6_info *match, - bool *do_rr) +static bool find_match(struct fib6_nh *nh, u32 fib6_flags, + int oif, int strict, int *mpri, bool *do_rr) { - int m; bool match_do_rr = false; + bool rc = false; + int m; - if (rt6_check_expired(rt)) + if (nh->fib_nh_flags & RTNH_F_DEAD) goto out; - m = rt6_score_route(rt, oif, strict); - if (m == RT6_NUD_FAIL_SOFT && !IS_ENABLED(CONFIG_IPV6_ROUTER_PREF)) { + if (ip6_ignore_linkdown(nh->fib_nh_dev) && + nh->fib_nh_flags & RTNH_F_LINKDOWN && + !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE)) + goto out; + + m = rt6_score_route(nh, fib6_flags, oif, strict); + if (m == RT6_NUD_FAIL_DO_RR) { match_do_rr = true; m = 0; /* lowest valid score */ - } else if (m < 0) { + } else if (m == RT6_NUD_FAIL_HARD) { goto out; } if (strict & RT6_LOOKUP_F_REACHABLE) - rt6_probe(rt); + rt6_probe(nh); + /* note that m can be RT6_NUD_FAIL_PROBE at this point */ if (m > *mpri) { *do_rr = match_do_rr; *mpri = m; - match = rt; + rc = true; } out: - return match; + return rc; } -static struct rt6_info *find_rr_leaf(struct fib6_node *fn, - struct rt6_info *rr_head, - u32 metric, int oif, int strict, - bool *do_rr) +struct fib6_nh_frl_arg { + u32 flags; + int oif; + int strict; + int *mpri; + bool *do_rr; + struct fib6_nh *nh; +}; + +static int rt6_nh_find_match(struct fib6_nh *nh, void *_arg) { - struct rt6_info *rt, *match; + struct fib6_nh_frl_arg *arg = _arg; + + arg->nh = nh; + return find_match(nh, arg->flags, arg->oif, arg->strict, + arg->mpri, arg->do_rr); +} + +static void __find_rr_leaf(struct fib6_info *f6i_start, + struct fib6_info *nomatch, u32 metric, + struct fib6_result *res, struct fib6_info **cont, + int oif, int strict, bool *do_rr, int *mpri) +{ + struct fib6_info *f6i; + + for (f6i = f6i_start; + f6i && f6i != nomatch; + f6i = rcu_dereference(f6i->fib6_next)) { + bool matched = false; + struct fib6_nh *nh; + + if (cont && f6i->fib6_metric != metric) { + *cont = f6i; + return; + } + + if (fib6_check_expired(f6i)) + continue; + + if (unlikely(f6i->nh)) { + struct fib6_nh_frl_arg arg = { + .flags = f6i->fib6_flags, + .oif = oif, + .strict = strict, + .mpri = mpri, + .do_rr = do_rr + }; + + if (nexthop_is_blackhole(f6i->nh)) { + res->fib6_flags = RTF_REJECT; + res->fib6_type = RTN_BLACKHOLE; + res->f6i = f6i; + res->nh = nexthop_fib6_nh(f6i->nh); + return; + } + if (nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_find_match, + &arg)) { + matched = true; + nh = arg.nh; + } + } else { + nh = f6i->fib6_nh; + if (find_match(nh, f6i->fib6_flags, oif, strict, + mpri, do_rr)) + matched = true; + } + if (matched) { + res->f6i = f6i; + res->nh = nh; + res->fib6_flags = f6i->fib6_flags; + res->fib6_type = f6i->fib6_type; + } + } +} + +static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf, + struct fib6_info *rr_head, int oif, int strict, + bool *do_rr, struct fib6_result *res) +{ + u32 metric = rr_head->fib6_metric; + struct fib6_info *cont = NULL; int mpri = -1; - match = NULL; - for (rt = rr_head; rt && rt->rt6i_metric == metric; - rt = rt->dst.rt6_next) - match = find_match(rt, oif, strict, &mpri, match, do_rr); - for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric; - rt = rt->dst.rt6_next) - match = find_match(rt, oif, strict, &mpri, match, do_rr); + __find_rr_leaf(rr_head, NULL, metric, res, &cont, + oif, strict, do_rr, &mpri); + + __find_rr_leaf(leaf, rr_head, metric, res, &cont, + oif, strict, do_rr, &mpri); + + if (res->f6i || !cont) + return; - return match; + __find_rr_leaf(cont, NULL, metric, res, NULL, + oif, strict, do_rr, &mpri); } -static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict) +static void rt6_select(struct net *net, struct fib6_node *fn, int oif, + struct fib6_result *res, int strict) { - struct rt6_info *match, *rt0; - struct net *net; + struct fib6_info *leaf = rcu_dereference(fn->leaf); + struct fib6_info *rt0; bool do_rr = false; + int key_plen; + + /* make sure this function or its helpers sets f6i */ + res->f6i = NULL; + + if (!leaf || leaf == net->ipv6.fib6_null_entry) + goto out; - rt0 = fn->rr_ptr; + rt0 = rcu_dereference(fn->rr_ptr); if (!rt0) - fn->rr_ptr = rt0 = fn->leaf; + rt0 = leaf; - match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict, - &do_rr); + /* Double check to make sure fn is not an intermediate node + * and fn->leaf does not points to its child's leaf + * (This might happen if all routes under fn are deleted from + * the tree and fib6_repair_tree() is called on the node.) + */ + key_plen = rt0->fib6_dst.plen; +#ifdef CONFIG_IPV6_SUBTREES + if (rt0->fib6_src.plen) + key_plen = rt0->fib6_src.plen; +#endif + if (fn->fn_bit != key_plen) + goto out; + find_rr_leaf(fn, leaf, rt0, oif, strict, &do_rr, res); if (do_rr) { - struct rt6_info *next = rt0->dst.rt6_next; + struct fib6_info *next = rcu_dereference(rt0->fib6_next); /* no entries matched; do round-robin */ - if (!next || next->rt6i_metric != rt0->rt6i_metric) - next = fn->leaf; + if (!next || next->fib6_metric != rt0->fib6_metric) + next = leaf; + + if (next != rt0) { + spin_lock_bh(&leaf->fib6_table->tb6_lock); + /* make sure next is not being deleted from the tree */ + if (next->fib6_node) + rcu_assign_pointer(fn->rr_ptr, next); + spin_unlock_bh(&leaf->fib6_table->tb6_lock); + } + } - if (next != rt0) - fn->rr_ptr = next; +out: + if (!res->f6i) { + res->f6i = net->ipv6.fib6_null_entry; + res->nh = res->f6i->fib6_nh; + res->fib6_flags = res->f6i->fib6_flags; + res->fib6_type = res->f6i->fib6_type; } +} - net = dev_net(rt0->dst.dev); - return match ? match : net->ipv6.ip6_null_entry; +static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res) +{ + return (res->f6i->fib6_flags & RTF_NONEXTHOP) || + res->nh->fib_nh_gw_family; } #ifdef CONFIG_IPV6_ROUTE_INFO @@ -669,9 +969,10 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, struct net *net = dev_net(dev); struct route_info *rinfo = (struct route_info *) opt; struct in6_addr prefix_buf, *prefix; + struct fib6_table *table; unsigned int pref; unsigned long lifetime; - struct rt6_info *rt; + struct fib6_info *rt; if (len < sizeof(struct route_info)) { return -EINVAL; @@ -708,82 +1009,308 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, prefix = &prefix_buf; } - rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr, - dev->ifindex); + if (rinfo->prefix_len == 0) + rt = rt6_get_dflt_router(net, gwaddr, dev); + else + rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, + gwaddr, dev); if (rt && !lifetime) { - ip6_del_rt(rt); + ip6_del_rt(net, rt, false); rt = NULL; } if (!rt && lifetime) - rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex, - pref); + rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, + dev, pref); else if (rt) - rt->rt6i_flags = RTF_ROUTEINFO | - (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); + rt->fib6_flags = RTF_ROUTEINFO | + (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); if (rt) { - if (!addrconf_finite_timeout(lifetime)) - rt6_clean_expires(rt); - else - rt6_set_expires(rt, jiffies + HZ * lifetime); + table = rt->fib6_table; + spin_lock_bh(&table->tb6_lock); - ip6_rt_put(rt); + if (!addrconf_finite_timeout(lifetime)) { + fib6_clean_expires(rt); + fib6_remove_gc_list(rt); + } else { + fib6_set_expires(rt, jiffies + HZ * lifetime); + fib6_add_gc_list(rt); + } + + spin_unlock_bh(&table->tb6_lock); + + fib6_info_release(rt); } return 0; } #endif -#define BACKTRACK(__net, saddr) \ -do { \ - if (rt == __net->ipv6.ip6_null_entry) { \ - struct fib6_node *pn; \ - while (1) { \ - if (fn->fn_flags & RTN_TL_ROOT) \ - goto out; \ - pn = fn->parent; \ - if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \ - fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \ - else \ - fn = pn; \ - if (fn->fn_flags & RTN_RTINFO) \ - goto restart; \ - } \ - } \ -} while (0) - -static struct rt6_info *ip6_pol_route_lookup(struct net *net, +/* + * Misc support functions + */ + +/* called with rcu_lock held */ +static struct net_device *ip6_rt_get_dev_rcu(const struct fib6_result *res) +{ + struct net_device *dev = res->nh->fib_nh_dev; + + if (res->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) { + /* for copies of local routes, dst->dev needs to be the + * device if it is a master device, the master device if + * device is enslaved, and the loopback as the default + */ + if (netif_is_l3_slave(dev) && + !rt6_need_strict(&res->f6i->fib6_dst.addr)) + dev = l3mdev_master_dev_rcu(dev); + else if (!netif_is_l3_master(dev)) + dev = dev_net(dev)->loopback_dev; + /* last case is netif_is_l3_master(dev) is true in which + * case we want dev returned to be dev + */ + } + + return dev; +} + +static const int fib6_prop[RTN_MAX + 1] = { + [RTN_UNSPEC] = 0, + [RTN_UNICAST] = 0, + [RTN_LOCAL] = 0, + [RTN_BROADCAST] = 0, + [RTN_ANYCAST] = 0, + [RTN_MULTICAST] = 0, + [RTN_BLACKHOLE] = -EINVAL, + [RTN_UNREACHABLE] = -EHOSTUNREACH, + [RTN_PROHIBIT] = -EACCES, + [RTN_THROW] = -EAGAIN, + [RTN_NAT] = -EINVAL, + [RTN_XRESOLVE] = -EINVAL, +}; + +static int ip6_rt_type_to_error(u8 fib6_type) +{ + return fib6_prop[fib6_type]; +} + +static unsigned short fib6_info_dst_flags(struct fib6_info *rt) +{ + unsigned short flags = 0; + + if (rt->dst_nocount) + flags |= DST_NOCOUNT; + if (rt->dst_nopolicy) + flags |= DST_NOPOLICY; + + return flags; +} + +static void ip6_rt_init_dst_reject(struct rt6_info *rt, u8 fib6_type) +{ + rt->dst.error = ip6_rt_type_to_error(fib6_type); + + switch (fib6_type) { + case RTN_BLACKHOLE: + rt->dst.output = dst_discard_out; + rt->dst.input = dst_discard; + break; + case RTN_PROHIBIT: + rt->dst.output = ip6_pkt_prohibit_out; + rt->dst.input = ip6_pkt_prohibit; + break; + case RTN_THROW: + case RTN_UNREACHABLE: + default: + rt->dst.output = ip6_pkt_discard_out; + rt->dst.input = ip6_pkt_discard; + break; + } +} + +static void ip6_rt_init_dst(struct rt6_info *rt, const struct fib6_result *res) +{ + struct fib6_info *f6i = res->f6i; + + if (res->fib6_flags & RTF_REJECT) { + ip6_rt_init_dst_reject(rt, res->fib6_type); + return; + } + + rt->dst.error = 0; + rt->dst.output = ip6_output; + + if (res->fib6_type == RTN_LOCAL || res->fib6_type == RTN_ANYCAST) { + rt->dst.input = ip6_input; + } else if (ipv6_addr_type(&f6i->fib6_dst.addr) & IPV6_ADDR_MULTICAST) { + rt->dst.input = ip6_mc_input; + rt->dst.output = ip6_mr_output; + } else { + rt->dst.input = ip6_forward; + } + + if (res->nh->fib_nh_lws) { + rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws); + lwtunnel_set_redirect(&rt->dst); + } + + rt->dst.lastuse = jiffies; +} + +/* Caller must already hold reference to @from */ +static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from) +{ + rt->rt6i_flags &= ~RTF_EXPIRES; + rcu_assign_pointer(rt->from, from); + ip_dst_init_metrics(&rt->dst, from->fib6_metrics); +} + +/* Caller must already hold reference to f6i in result */ +static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res) +{ + const struct fib6_nh *nh = res->nh; + const struct net_device *dev = nh->fib_nh_dev; + struct fib6_info *f6i = res->f6i; + + ip6_rt_init_dst(rt, res); + + rt->rt6i_dst = f6i->fib6_dst; + rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL; + rt->rt6i_flags = res->fib6_flags; + if (nh->fib_nh_gw_family) { + rt->rt6i_gateway = nh->fib_nh_gw6; + rt->rt6i_flags |= RTF_GATEWAY; + } + rt6_set_from(rt, f6i); +#ifdef CONFIG_IPV6_SUBTREES + rt->rt6i_src = f6i->fib6_src; +#endif +} + +static struct fib6_node* fib6_backtrack(struct fib6_node *fn, + struct in6_addr *saddr) +{ + struct fib6_node *pn, *sn; + while (1) { + if (fn->fn_flags & RTN_TL_ROOT) + return NULL; + pn = rcu_dereference(fn->parent); + sn = FIB6_SUBTREE(pn); + if (sn && sn != fn) + fn = fib6_node_lookup(sn, NULL, saddr); + else + fn = pn; + if (fn->fn_flags & RTN_RTINFO) + return fn; + } +} + +static bool ip6_hold_safe(struct net *net, struct rt6_info **prt) +{ + struct rt6_info *rt = *prt; + + if (dst_hold_safe(&rt->dst)) + return true; + if (net) { + rt = net->ipv6.ip6_null_entry; + dst_hold(&rt->dst); + } else { + rt = NULL; + } + *prt = rt; + return false; +} + +/* called with rcu_lock held */ +static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res) +{ + struct net_device *dev = res->nh->fib_nh_dev; + struct fib6_info *f6i = res->f6i; + unsigned short flags; + struct rt6_info *nrt; + + if (!fib6_info_hold_safe(f6i)) + goto fallback; + + flags = fib6_info_dst_flags(f6i); + nrt = ip6_dst_alloc(dev_net(dev), dev, flags); + if (!nrt) { + fib6_info_release(f6i); + goto fallback; + } + + ip6_rt_copy_init(nrt, res); + return nrt; + +fallback: + nrt = dev_net(dev)->ipv6.ip6_null_entry; + dst_hold(&nrt->dst); + return nrt; +} + +INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_lookup(struct net *net, struct fib6_table *table, - struct flowi6 *fl6, int flags) + struct flowi6 *fl6, + const struct sk_buff *skb, + int flags) { + struct fib6_result res = {}; struct fib6_node *fn; struct rt6_info *rt; - read_lock_bh(&table->tb6_lock); - fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); + rcu_read_lock(); + fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); restart: - rt = fn->leaf; - rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags); - if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0) - rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags); - BACKTRACK(net, &fl6->saddr); + res.f6i = rcu_dereference(fn->leaf); + if (!res.f6i) + res.f6i = net->ipv6.fib6_null_entry; + else + rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif, + flags); + + if (res.f6i == net->ipv6.fib6_null_entry) { + fn = fib6_backtrack(fn, &fl6->saddr); + if (fn) + goto restart; + + rt = net->ipv6.ip6_null_entry; + dst_hold(&rt->dst); + goto out; + } else if (res.fib6_flags & RTF_REJECT) { + goto do_create; + } + + fib6_select_path(net, &res, fl6, fl6->flowi6_oif, + fl6->flowi6_oif != 0, skb, flags); + + /* Search through exception table */ + rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr); + if (rt) { + if (ip6_hold_safe(net, &rt)) + dst_use_noref(&rt->dst, jiffies); + } else { +do_create: + rt = ip6_create_rt_rcu(&res); + } + out: - dst_use(&rt->dst, jiffies); - read_unlock_bh(&table->tb6_lock); - return rt; + trace_fib6_table_lookup(net, &res, table, fl6); + rcu_read_unlock(); + + return rt; } -struct dst_entry * ip6_route_lookup(struct net *net, struct flowi6 *fl6, - int flags) +struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6, + const struct sk_buff *skb, int flags) { - return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup); + return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_lookup); } EXPORT_SYMBOL_GPL(ip6_route_lookup); struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, - const struct in6_addr *saddr, int oif, int strict) + const struct in6_addr *saddr, int oif, + const struct sk_buff *skb, int strict) { struct flowi6 fl6 = { .flowi6_oif = oif, @@ -797,66 +1324,74 @@ struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, flags |= RT6_LOOKUP_F_HAS_SADDR; } - dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup); + dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup); if (dst->error == 0) - return (struct rt6_info *) dst; + return dst_rt6_info(dst); dst_release(dst); return NULL; } - EXPORT_SYMBOL(rt6_lookup); /* ip6_ins_rt is called with FREE table->tb6_lock. - It takes new route entry, the addition fails by any reason the - route is freed. In any case, if caller does not hold it, it may - be destroyed. + * It takes new route entry, the addition fails by any reason the + * route is released. + * Caller must hold dst before calling it. */ -static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info) +static int __ip6_ins_rt(struct fib6_info *rt, struct nl_info *info, + struct netlink_ext_ack *extack) { int err; struct fib6_table *table; - table = rt->rt6i_table; - write_lock_bh(&table->tb6_lock); - err = fib6_add(&table->tb6_root, rt, info); - write_unlock_bh(&table->tb6_lock); + table = rt->fib6_table; + spin_lock_bh(&table->tb6_lock); + err = fib6_add(&table->tb6_root, rt, info, extack); + spin_unlock_bh(&table->tb6_lock); return err; } -int ip6_ins_rt(struct rt6_info *rt) +int ip6_ins_rt(struct net *net, struct fib6_info *rt) { - struct nl_info info = { - .nl_net = dev_net(rt->dst.dev), - }; - return __ip6_ins_rt(rt, &info); + struct nl_info info = { .nl_net = net, }; + + return __ip6_ins_rt(rt, &info, NULL); } -static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, - const struct in6_addr *daddr, - const struct in6_addr *saddr) +static struct rt6_info *ip6_rt_cache_alloc(const struct fib6_result *res, + const struct in6_addr *daddr, + const struct in6_addr *saddr) { + struct fib6_info *f6i = res->f6i; + struct net_device *dev; struct rt6_info *rt; /* * Clone the route. */ - rt = ip6_rt_copy(ort, daddr); + if (!fib6_info_hold_safe(f6i)) + return NULL; - if (rt) { - if (!(rt->rt6i_flags & RTF_GATEWAY)) { - if (ort->rt6i_dst.plen != 128 && - ipv6_addr_equal(&ort->rt6i_dst.addr, daddr)) - rt->rt6i_flags |= RTF_ANYCAST; - rt->rt6i_gateway = *daddr; - } + dev = ip6_rt_get_dev_rcu(res); + rt = ip6_dst_alloc(dev_net(dev), dev, 0); + if (!rt) { + fib6_info_release(f6i); + return NULL; + } - rt->rt6i_flags |= RTF_CACHE; + ip6_rt_copy_init(rt, res); + rt->rt6i_flags |= RTF_CACHE; + rt->rt6i_dst.addr = *daddr; + rt->rt6i_dst.plen = 128; + if (!rt6_is_gw_or_nonexthop(res)) { + if (f6i->fib6_dst.plen != 128 && + ipv6_addr_equal(&f6i->fib6_dst.addr, daddr)) + rt->rt6i_flags |= RTF_ANYCAST; #ifdef CONFIG_IPV6_SUBTREES if (rt->rt6i_src.plen && saddr) { rt->rt6i_src.addr = *saddr; @@ -868,108 +1403,1221 @@ static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, return rt; } -static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, - const struct in6_addr *daddr) +static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res) { - struct rt6_info *rt = ip6_rt_copy(ort, daddr); + struct fib6_info *f6i = res->f6i; + unsigned short flags = fib6_info_dst_flags(f6i); + struct net_device *dev; + struct rt6_info *pcpu_rt; - if (rt) - rt->rt6i_flags |= RTF_CACHE; - return rt; + if (!fib6_info_hold_safe(f6i)) + return NULL; + + rcu_read_lock(); + dev = ip6_rt_get_dev_rcu(res); + pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags | DST_NOCOUNT); + rcu_read_unlock(); + if (!pcpu_rt) { + fib6_info_release(f6i); + return NULL; + } + ip6_rt_copy_init(pcpu_rt, res); + pcpu_rt->rt6i_flags |= RTF_PCPU; + + if (f6i->nh) + pcpu_rt->sernum = rt_genid_ipv6(dev_net(dev)); + + return pcpu_rt; } -static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif, - struct flowi6 *fl6, int flags) +static bool rt6_is_valid(const struct rt6_info *rt6) { - struct fib6_node *fn; - struct rt6_info *rt, *nrt; - int strict = 0; - int attempts = 3; - int err; - int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE; + return rt6->sernum == rt_genid_ipv6(dev_net(rt6->dst.dev)); +} - strict |= flags & RT6_LOOKUP_F_IFACE; +/* It should be called with rcu_read_lock() acquired */ +static struct rt6_info *rt6_get_pcpu_route(const struct fib6_result *res) +{ + struct rt6_info *pcpu_rt; -relookup: - read_lock_bh(&table->tb6_lock); + pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu); -restart_2: - fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); + if (pcpu_rt && pcpu_rt->sernum && !rt6_is_valid(pcpu_rt)) { + struct rt6_info *prev, **p; -restart: - rt = rt6_select(fn, oif, strict | reachable); - if (rt->rt6i_nsiblings) - rt = rt6_multipath_select(rt, fl6, oif, strict | reachable); - BACKTRACK(net, &fl6->saddr); - if (rt == net->ipv6.ip6_null_entry || - rt->rt6i_flags & RTF_CACHE) - goto out; + p = this_cpu_ptr(res->nh->rt6i_pcpu); + /* Paired with READ_ONCE() in __fib6_drop_pcpu_from() */ + prev = xchg(p, NULL); + if (prev) { + dst_dev_put(&prev->dst); + dst_release(&prev->dst); + } + + pcpu_rt = NULL; + } + + return pcpu_rt; +} + +static struct rt6_info *rt6_make_pcpu_route(struct net *net, + const struct fib6_result *res) +{ + struct rt6_info *pcpu_rt, *prev, **p; + + pcpu_rt = ip6_rt_pcpu_alloc(res); + if (!pcpu_rt) + return NULL; + + p = this_cpu_ptr(res->nh->rt6i_pcpu); + prev = cmpxchg(p, NULL, pcpu_rt); + BUG_ON(prev); + + if (res->f6i->fib6_destroying) { + struct fib6_info *from; + + from = unrcu_pointer(xchg(&pcpu_rt->from, NULL)); + fib6_info_release(from); + } + + return pcpu_rt; +} + +/* exception hash table implementation + */ +static DEFINE_SPINLOCK(rt6_exception_lock); + +/* Remove rt6_ex from hash table and free the memory + * Caller must hold rt6_exception_lock + */ +static void rt6_remove_exception(struct rt6_exception_bucket *bucket, + struct rt6_exception *rt6_ex) +{ + struct net *net; + + if (!bucket || !rt6_ex) + return; + + net = dev_net(rt6_ex->rt6i->dst.dev); + net->ipv6.rt6_stats->fib_rt_cache--; + + /* purge completely the exception to allow releasing the held resources: + * some [sk] cache may keep the dst around for unlimited time + */ + dst_dev_put(&rt6_ex->rt6i->dst); + + hlist_del_rcu(&rt6_ex->hlist); + dst_release(&rt6_ex->rt6i->dst); + kfree_rcu(rt6_ex, rcu); + WARN_ON_ONCE(!bucket->depth); + bucket->depth--; +} + +/* Remove oldest rt6_ex in bucket and free the memory + * Caller must hold rt6_exception_lock + */ +static void rt6_exception_remove_oldest(struct rt6_exception_bucket *bucket) +{ + struct rt6_exception *rt6_ex, *oldest = NULL; + + if (!bucket) + return; + + hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) { + if (!oldest || time_before(rt6_ex->stamp, oldest->stamp)) + oldest = rt6_ex; + } + rt6_remove_exception(bucket, oldest); +} + +static u32 rt6_exception_hash(const struct in6_addr *dst, + const struct in6_addr *src) +{ + static siphash_aligned_key_t rt6_exception_key; + struct { + struct in6_addr dst; + struct in6_addr src; + } __aligned(SIPHASH_ALIGNMENT) combined = { + .dst = *dst, + }; + u64 val; + + net_get_random_once(&rt6_exception_key, sizeof(rt6_exception_key)); + +#ifdef CONFIG_IPV6_SUBTREES + if (src) + combined.src = *src; +#endif + val = siphash(&combined, sizeof(combined), &rt6_exception_key); + + return hash_64(val, FIB6_EXCEPTION_BUCKET_SIZE_SHIFT); +} + +/* Helper function to find the cached rt in the hash table + * and update bucket pointer to point to the bucket for this + * (daddr, saddr) pair + * Caller must hold rt6_exception_lock + */ +static struct rt6_exception * +__rt6_find_exception_spinlock(struct rt6_exception_bucket **bucket, + const struct in6_addr *daddr, + const struct in6_addr *saddr) +{ + struct rt6_exception *rt6_ex; + u32 hval; + + if (!(*bucket) || !daddr) + return NULL; + + hval = rt6_exception_hash(daddr, saddr); + *bucket += hval; - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); + hlist_for_each_entry(rt6_ex, &(*bucket)->chain, hlist) { + struct rt6_info *rt6 = rt6_ex->rt6i; + bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr); - if (!(rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY))) - nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr); - else if (!(rt->dst.flags & DST_HOST)) - nrt = rt6_alloc_clone(rt, &fl6->daddr); +#ifdef CONFIG_IPV6_SUBTREES + if (matched && saddr) + matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr); +#endif + if (matched) + return rt6_ex; + } + return NULL; +} + +/* Helper function to find the cached rt in the hash table + * and update bucket pointer to point to the bucket for this + * (daddr, saddr) pair + * Caller must hold rcu_read_lock() + */ +static struct rt6_exception * +__rt6_find_exception_rcu(struct rt6_exception_bucket **bucket, + const struct in6_addr *daddr, + const struct in6_addr *saddr) +{ + struct rt6_exception *rt6_ex; + u32 hval; + + WARN_ON_ONCE(!rcu_read_lock_held()); + + if (!(*bucket) || !daddr) + return NULL; + + hval = rt6_exception_hash(daddr, saddr); + *bucket += hval; + + hlist_for_each_entry_rcu(rt6_ex, &(*bucket)->chain, hlist) { + struct rt6_info *rt6 = rt6_ex->rt6i; + bool matched = ipv6_addr_equal(daddr, &rt6->rt6i_dst.addr); + +#ifdef CONFIG_IPV6_SUBTREES + if (matched && saddr) + matched = ipv6_addr_equal(saddr, &rt6->rt6i_src.addr); +#endif + if (matched) + return rt6_ex; + } + return NULL; +} + +static unsigned int fib6_mtu(const struct fib6_result *res) +{ + const struct fib6_nh *nh = res->nh; + unsigned int mtu; + + if (res->f6i->fib6_pmtu) { + mtu = res->f6i->fib6_pmtu; + } else { + struct net_device *dev = nh->fib_nh_dev; + struct inet6_dev *idev; + + rcu_read_lock(); + idev = __in6_dev_get(dev); + mtu = READ_ONCE(idev->cnf.mtu6); + rcu_read_unlock(); + } + + mtu = min_t(unsigned int, mtu, IP6_MAX_MTU); + + return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu); +} + +#define FIB6_EXCEPTION_BUCKET_FLUSHED 0x1UL + +/* used when the flushed bit is not relevant, only access to the bucket + * (ie., all bucket users except rt6_insert_exception); + * + * called under rcu lock; sometimes called with rt6_exception_lock held + */ +static +struct rt6_exception_bucket *fib6_nh_get_excptn_bucket(const struct fib6_nh *nh, + spinlock_t *lock) +{ + struct rt6_exception_bucket *bucket; + + if (lock) + bucket = rcu_dereference_protected(nh->rt6i_exception_bucket, + lockdep_is_held(lock)); else - goto out2; + bucket = rcu_dereference(nh->rt6i_exception_bucket); - ip6_rt_put(rt); - rt = nrt ? : net->ipv6.ip6_null_entry; + /* remove bucket flushed bit if set */ + if (bucket) { + unsigned long p = (unsigned long)bucket; - dst_hold(&rt->dst); - if (nrt) { - err = ip6_ins_rt(nrt); - if (!err) - goto out2; + p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED; + bucket = (struct rt6_exception_bucket *)p; } - if (--attempts <= 0) - goto out2; + return bucket; +} - /* - * Race condition! In the gap, when table->tb6_lock was - * released someone could insert this route. Relookup. +static bool fib6_nh_excptn_bucket_flushed(struct rt6_exception_bucket *bucket) +{ + unsigned long p = (unsigned long)bucket; + + return !!(p & FIB6_EXCEPTION_BUCKET_FLUSHED); +} + +/* called with rt6_exception_lock held */ +static void fib6_nh_excptn_bucket_set_flushed(struct fib6_nh *nh, + spinlock_t *lock) +{ + struct rt6_exception_bucket *bucket; + unsigned long p; + + bucket = rcu_dereference_protected(nh->rt6i_exception_bucket, + lockdep_is_held(lock)); + + p = (unsigned long)bucket; + p |= FIB6_EXCEPTION_BUCKET_FLUSHED; + bucket = (struct rt6_exception_bucket *)p; + rcu_assign_pointer(nh->rt6i_exception_bucket, bucket); +} + +static int rt6_insert_exception(struct rt6_info *nrt, + const struct fib6_result *res) +{ + struct net *net = dev_net(nrt->dst.dev); + struct rt6_exception_bucket *bucket; + struct fib6_info *f6i = res->f6i; + struct in6_addr *src_key = NULL; + struct rt6_exception *rt6_ex; + struct fib6_nh *nh = res->nh; + int max_depth; + int err = 0; + + spin_lock_bh(&rt6_exception_lock); + + bucket = rcu_dereference_protected(nh->rt6i_exception_bucket, + lockdep_is_held(&rt6_exception_lock)); + if (!bucket) { + bucket = kcalloc(FIB6_EXCEPTION_BUCKET_SIZE, sizeof(*bucket), + GFP_ATOMIC); + if (!bucket) { + err = -ENOMEM; + goto out; + } + rcu_assign_pointer(nh->rt6i_exception_bucket, bucket); + } else if (fib6_nh_excptn_bucket_flushed(bucket)) { + err = -EINVAL; + goto out; + } + +#ifdef CONFIG_IPV6_SUBTREES + /* fib6_src.plen != 0 indicates f6i is in subtree + * and exception table is indexed by a hash of + * both fib6_dst and fib6_src. + * Otherwise, the exception table is indexed by + * a hash of only fib6_dst. */ - ip6_rt_put(rt); - goto relookup; + if (f6i->fib6_src.plen) + src_key = &nrt->rt6i_src.addr; +#endif + /* rt6_mtu_change() might lower mtu on f6i. + * Only insert this exception route if its mtu + * is less than f6i's mtu value. + */ + if (dst_metric_raw(&nrt->dst, RTAX_MTU) >= fib6_mtu(res)) { + err = -EINVAL; + goto out; + } + + rt6_ex = __rt6_find_exception_spinlock(&bucket, &nrt->rt6i_dst.addr, + src_key); + if (rt6_ex) + rt6_remove_exception(bucket, rt6_ex); + + rt6_ex = kzalloc(sizeof(*rt6_ex), GFP_ATOMIC); + if (!rt6_ex) { + err = -ENOMEM; + goto out; + } + rt6_ex->rt6i = nrt; + rt6_ex->stamp = jiffies; + hlist_add_head_rcu(&rt6_ex->hlist, &bucket->chain); + bucket->depth++; + net->ipv6.rt6_stats->fib_rt_cache++; + + /* Randomize max depth to avoid some side channels attacks. */ + max_depth = FIB6_MAX_DEPTH + get_random_u32_below(FIB6_MAX_DEPTH); + while (bucket->depth > max_depth) + rt6_exception_remove_oldest(bucket); out: - if (reachable) { - reachable = 0; - goto restart_2; + spin_unlock_bh(&rt6_exception_lock); + + /* Update fn->fn_sernum to invalidate all cached dst */ + if (!err) { + spin_lock_bh(&f6i->fib6_table->tb6_lock); + fib6_update_sernum(net, f6i); + fib6_add_gc_list(f6i); + spin_unlock_bh(&f6i->fib6_table->tb6_lock); + fib6_force_start_gc(net); } - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); -out2: - rt->dst.lastuse = jiffies; - rt->dst.__use++; + + return err; +} + +static void fib6_nh_flush_exceptions(struct fib6_nh *nh, struct fib6_info *from) +{ + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + struct hlist_node *tmp; + int i; + + spin_lock_bh(&rt6_exception_lock); + + bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock); + if (!bucket) + goto out; + + /* Prevent rt6_insert_exception() to recreate the bucket list */ + if (!from) + fib6_nh_excptn_bucket_set_flushed(nh, &rt6_exception_lock); + + for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) { + hlist_for_each_entry_safe(rt6_ex, tmp, &bucket->chain, hlist) { + if (!from || + rcu_access_pointer(rt6_ex->rt6i->from) == from) + rt6_remove_exception(bucket, rt6_ex); + } + WARN_ON_ONCE(!from && bucket->depth); + bucket++; + } +out: + spin_unlock_bh(&rt6_exception_lock); +} + +static int rt6_nh_flush_exceptions(struct fib6_nh *nh, void *arg) +{ + struct fib6_info *f6i = arg; + + fib6_nh_flush_exceptions(nh, f6i); + + return 0; +} + +void rt6_flush_exceptions(struct fib6_info *f6i) +{ + if (f6i->nh) { + rcu_read_lock(); + nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions, f6i); + rcu_read_unlock(); + } else { + fib6_nh_flush_exceptions(f6i->fib6_nh, f6i); + } +} + +/* Find cached rt in the hash table inside passed in rt + * Caller has to hold rcu_read_lock() + */ +static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res, + const struct in6_addr *daddr, + const struct in6_addr *saddr) +{ + const struct in6_addr *src_key = NULL; + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + struct rt6_info *ret = NULL; + +#ifdef CONFIG_IPV6_SUBTREES + /* fib6i_src.plen != 0 indicates f6i is in subtree + * and exception table is indexed by a hash of + * both fib6_dst and fib6_src. + * However, the src addr used to create the hash + * might not be exactly the passed in saddr which + * is a /128 addr from the flow. + * So we need to use f6i->fib6_src to redo lookup + * if the passed in saddr does not find anything. + * (See the logic in ip6_rt_cache_alloc() on how + * rt->rt6i_src is updated.) + */ + if (res->f6i->fib6_src.plen) + src_key = saddr; +find_ex: +#endif + bucket = fib6_nh_get_excptn_bucket(res->nh, NULL); + rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key); + + if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i)) + ret = rt6_ex->rt6i; + +#ifdef CONFIG_IPV6_SUBTREES + /* Use fib6_src as src_key and redo lookup */ + if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) { + src_key = &res->f6i->fib6_src.addr; + goto find_ex; + } +#endif + + return ret; +} + +/* Remove the passed in cached rt from the hash table that contains it */ +static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen, + const struct rt6_info *rt) +{ + const struct in6_addr *src_key = NULL; + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + int err; + + if (!rcu_access_pointer(nh->rt6i_exception_bucket)) + return -ENOENT; + + spin_lock_bh(&rt6_exception_lock); + bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock); + +#ifdef CONFIG_IPV6_SUBTREES + /* rt6i_src.plen != 0 indicates 'from' is in subtree + * and exception table is indexed by a hash of + * both rt6i_dst and rt6i_src. + * Otherwise, the exception table is indexed by + * a hash of only rt6i_dst. + */ + if (plen) + src_key = &rt->rt6i_src.addr; +#endif + rt6_ex = __rt6_find_exception_spinlock(&bucket, + &rt->rt6i_dst.addr, + src_key); + if (rt6_ex) { + rt6_remove_exception(bucket, rt6_ex); + err = 0; + } else { + err = -ENOENT; + } + + spin_unlock_bh(&rt6_exception_lock); + return err; +} + +struct fib6_nh_excptn_arg { + struct rt6_info *rt; + int plen; +}; + +static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_excptn_arg *arg = _arg; + int err; + + err = fib6_nh_remove_exception(nh, arg->plen, arg->rt); + if (err == 0) + return 1; + + return 0; +} + +static int rt6_remove_exception_rt(struct rt6_info *rt) +{ + struct fib6_info *from; + + from = rcu_dereference(rt->from); + if (!from || !(rt->rt6i_flags & RTF_CACHE)) + return -EINVAL; + + if (from->nh) { + struct fib6_nh_excptn_arg arg = { + .rt = rt, + .plen = from->fib6_src.plen + }; + int rc; + + /* rc = 1 means an entry was found */ + rc = nexthop_for_each_fib6_nh(from->nh, + rt6_nh_remove_exception_rt, + &arg); + return rc ? 0 : -ENOENT; + } + + return fib6_nh_remove_exception(from->fib6_nh, + from->fib6_src.plen, rt); +} + +/* Find rt6_ex which contains the passed in rt cache and + * refresh its stamp + */ +static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen, + const struct rt6_info *rt) +{ + const struct in6_addr *src_key = NULL; + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + + bucket = fib6_nh_get_excptn_bucket(nh, NULL); +#ifdef CONFIG_IPV6_SUBTREES + /* rt6i_src.plen != 0 indicates 'from' is in subtree + * and exception table is indexed by a hash of + * both rt6i_dst and rt6i_src. + * Otherwise, the exception table is indexed by + * a hash of only rt6i_dst. + */ + if (plen) + src_key = &rt->rt6i_src.addr; +#endif + rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key); + if (rt6_ex) + rt6_ex->stamp = jiffies; +} + +struct fib6_nh_match_arg { + const struct net_device *dev; + const struct in6_addr *gw; + struct fib6_nh *match; +}; + +/* determine if fib6_nh has given device and gateway */ +static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_match_arg *arg = _arg; + + if (arg->dev != nh->fib_nh_dev || + (arg->gw && !nh->fib_nh_gw_family) || + (!arg->gw && nh->fib_nh_gw_family) || + (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6))) + return 0; + + arg->match = nh; + + /* found a match, break the loop */ + return 1; +} + +static void rt6_update_exception_stamp_rt(struct rt6_info *rt) +{ + struct fib6_info *from; + struct fib6_nh *fib6_nh; + + rcu_read_lock(); + + from = rcu_dereference(rt->from); + if (!from || !(rt->rt6i_flags & RTF_CACHE)) + goto unlock; + + if (from->nh) { + struct fib6_nh_match_arg arg = { + .dev = rt->dst.dev, + .gw = &rt->rt6i_gateway, + }; + + nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg); + + if (!arg.match) + goto unlock; + fib6_nh = arg.match; + } else { + fib6_nh = from->fib6_nh; + } + fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt); +unlock: + rcu_read_unlock(); +} + +static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev, + struct rt6_info *rt, int mtu) +{ + /* If the new MTU is lower than the route PMTU, this new MTU will be the + * lowest MTU in the path: always allow updating the route PMTU to + * reflect PMTU decreases. + * + * If the new MTU is higher, and the route PMTU is equal to the local + * MTU, this means the old MTU is the lowest in the path, so allow + * updating it: if other nodes now have lower MTUs, PMTU discovery will + * handle this. + */ + + if (dst_mtu(&rt->dst) >= mtu) + return true; + + if (dst_mtu(&rt->dst) == idev->cnf.mtu6) + return true; + + return false; +} + +static void rt6_exceptions_update_pmtu(struct inet6_dev *idev, + const struct fib6_nh *nh, int mtu) +{ + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + int i; + + bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock); + if (!bucket) + return; + + for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) { + hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) { + struct rt6_info *entry = rt6_ex->rt6i; + + /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected + * route), the metrics of its rt->from have already + * been updated. + */ + if (dst_metric_raw(&entry->dst, RTAX_MTU) && + rt6_mtu_change_route_allowed(idev, entry, mtu)) + dst_metric_set(&entry->dst, RTAX_MTU, mtu); + } + bucket++; + } +} + +#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE) + +static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh, + const struct in6_addr *gateway) +{ + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + struct hlist_node *tmp; + int i; + + if (!rcu_access_pointer(nh->rt6i_exception_bucket)) + return; + + spin_lock_bh(&rt6_exception_lock); + bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock); + if (bucket) { + for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) { + hlist_for_each_entry_safe(rt6_ex, tmp, + &bucket->chain, hlist) { + struct rt6_info *entry = rt6_ex->rt6i; + + if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) == + RTF_CACHE_GATEWAY && + ipv6_addr_equal(gateway, + &entry->rt6i_gateway)) { + rt6_remove_exception(bucket, rt6_ex); + } + } + bucket++; + } + } + + spin_unlock_bh(&rt6_exception_lock); +} + +static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket, + struct rt6_exception *rt6_ex, + struct fib6_gc_args *gc_args, + unsigned long now) +{ + struct rt6_info *rt = rt6_ex->rt6i; + + /* we are pruning and obsoleting aged-out and non gateway exceptions + * even if others have still references to them, so that on next + * dst_check() such references can be dropped. + * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when + * expired, independently from their aging, as per RFC 8201 section 4 + */ + if (!(rt->rt6i_flags & RTF_EXPIRES)) { + if (time_after_eq(now, READ_ONCE(rt->dst.lastuse) + + gc_args->timeout)) { + pr_debug("aging clone %p\n", rt); + rt6_remove_exception(bucket, rt6_ex); + return; + } + } else if (time_after(jiffies, READ_ONCE(rt->dst.expires))) { + pr_debug("purging expired route %p\n", rt); + rt6_remove_exception(bucket, rt6_ex); + return; + } + + if (rt->rt6i_flags & RTF_GATEWAY) { + struct neighbour *neigh; + + neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway); + + if (!(neigh && (neigh->flags & NTF_ROUTER))) { + pr_debug("purging route %p via non-router but gateway\n", + rt); + rt6_remove_exception(bucket, rt6_ex); + return; + } + } + + gc_args->more++; +} + +static void fib6_nh_age_exceptions(const struct fib6_nh *nh, + struct fib6_gc_args *gc_args, + unsigned long now) +{ + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + struct hlist_node *tmp; + int i; + + if (!rcu_access_pointer(nh->rt6i_exception_bucket)) + return; + + rcu_read_lock_bh(); + spin_lock(&rt6_exception_lock); + bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock); + if (bucket) { + for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) { + hlist_for_each_entry_safe(rt6_ex, tmp, + &bucket->chain, hlist) { + rt6_age_examine_exception(bucket, rt6_ex, + gc_args, now); + } + bucket++; + } + } + spin_unlock(&rt6_exception_lock); + rcu_read_unlock_bh(); +} + +struct fib6_nh_age_excptn_arg { + struct fib6_gc_args *gc_args; + unsigned long now; +}; + +static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_age_excptn_arg *arg = _arg; + + fib6_nh_age_exceptions(nh, arg->gc_args, arg->now); + return 0; +} + +void rt6_age_exceptions(struct fib6_info *f6i, + struct fib6_gc_args *gc_args, + unsigned long now) +{ + if (f6i->nh) { + struct fib6_nh_age_excptn_arg arg = { + .gc_args = gc_args, + .now = now + }; + + nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions, + &arg); + } else { + fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now); + } +} + +/* must be called with rcu lock held */ +int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif, + struct flowi6 *fl6, struct fib6_result *res, int strict) +{ + struct fib6_node *fn, *saved_fn; + + fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); + saved_fn = fn; + +redo_rt6_select: + rt6_select(net, fn, oif, res, strict); + if (res->f6i == net->ipv6.fib6_null_entry) { + fn = fib6_backtrack(fn, &fl6->saddr); + if (fn) + goto redo_rt6_select; + else if (strict & RT6_LOOKUP_F_REACHABLE) { + /* also consider unreachable route */ + strict &= ~RT6_LOOKUP_F_REACHABLE; + fn = saved_fn; + goto redo_rt6_select; + } + } + + trace_fib6_table_lookup(net, res, table, fl6); + + return 0; +} + +struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, + int oif, struct flowi6 *fl6, + const struct sk_buff *skb, int flags) +{ + struct fib6_result res = {}; + struct rt6_info *rt = NULL; + int strict = 0; + + WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) && + !rcu_read_lock_held()); + + strict |= flags & RT6_LOOKUP_F_IFACE; + strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE; + if (READ_ONCE(net->ipv6.devconf_all->forwarding) == 0) + strict |= RT6_LOOKUP_F_REACHABLE; + + rcu_read_lock(); + + fib6_table_lookup(net, table, oif, fl6, &res, strict); + if (res.f6i == net->ipv6.fib6_null_entry) + goto out; + + fib6_select_path(net, &res, fl6, oif, false, skb, strict); + + /*Search through exception table */ + rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr); + if (rt) { + goto out; + } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) && + !res.nh->fib_nh_gw_family)) { + /* Create a RTF_CACHE clone which will not be + * owned by the fib6 tree. It is for the special case where + * the daddr in the skb during the neighbor look-up is different + * from the fl6->daddr used to look-up route here. + */ + rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL); + + if (rt) { + /* 1 refcnt is taken during ip6_rt_cache_alloc(). + * As rt6_uncached_list_add() does not consume refcnt, + * this refcnt is always returned to the caller even + * if caller sets RT6_LOOKUP_F_DST_NOREF flag. + */ + rt6_uncached_list_add(rt); + rcu_read_unlock(); + + return rt; + } + } else { + /* Get a percpu copy */ + local_bh_disable(); + rt = rt6_get_pcpu_route(&res); + + if (!rt) + rt = rt6_make_pcpu_route(net, &res); + + local_bh_enable(); + } +out: + if (!rt) + rt = net->ipv6.ip6_null_entry; + if (!(flags & RT6_LOOKUP_F_DST_NOREF)) + ip6_hold_safe(net, &rt); + rcu_read_unlock(); return rt; } +EXPORT_SYMBOL_GPL(ip6_pol_route); -static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table, - struct flowi6 *fl6, int flags) +INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_input(struct net *net, + struct fib6_table *table, + struct flowi6 *fl6, + const struct sk_buff *skb, + int flags) { - return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags); + return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, skb, flags); } -static struct dst_entry *ip6_route_input_lookup(struct net *net, - struct net_device *dev, - struct flowi6 *fl6, int flags) +struct dst_entry *ip6_route_input_lookup(struct net *net, + struct net_device *dev, + struct flowi6 *fl6, + const struct sk_buff *skb, + int flags) { if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG) flags |= RT6_LOOKUP_F_IFACE; - return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input); + return fib6_rule_lookup(net, fl6, skb, flags, ip6_pol_route_input); +} +EXPORT_SYMBOL_GPL(ip6_route_input_lookup); + +static void ip6_multipath_l3_keys(const struct sk_buff *skb, + struct flow_keys *keys, + struct flow_keys *flkeys) +{ + const struct ipv6hdr *outer_iph = ipv6_hdr(skb); + const struct ipv6hdr *key_iph = outer_iph; + struct flow_keys *_flkeys = flkeys; + const struct ipv6hdr *inner_iph; + const struct icmp6hdr *icmph; + struct ipv6hdr _inner_iph; + struct icmp6hdr _icmph; + + if (likely(outer_iph->nexthdr != IPPROTO_ICMPV6)) + goto out; + + icmph = skb_header_pointer(skb, skb_transport_offset(skb), + sizeof(_icmph), &_icmph); + if (!icmph) + goto out; + + if (!icmpv6_is_err(icmph->icmp6_type)) + goto out; + + inner_iph = skb_header_pointer(skb, + skb_transport_offset(skb) + sizeof(*icmph), + sizeof(_inner_iph), &_inner_iph); + if (!inner_iph) + goto out; + + key_iph = inner_iph; + _flkeys = NULL; +out: + if (_flkeys) { + keys->addrs.v6addrs.src = _flkeys->addrs.v6addrs.src; + keys->addrs.v6addrs.dst = _flkeys->addrs.v6addrs.dst; + keys->tags.flow_label = _flkeys->tags.flow_label; + keys->basic.ip_proto = _flkeys->basic.ip_proto; + } else { + keys->addrs.v6addrs.src = key_iph->saddr; + keys->addrs.v6addrs.dst = key_iph->daddr; + keys->tags.flow_label = ip6_flowlabel(key_iph); + keys->basic.ip_proto = key_iph->nexthdr; + } +} + +static u32 rt6_multipath_custom_hash_outer(const struct net *net, + const struct sk_buff *skb, + bool *p_has_inner) +{ + u32 hash_fields = ip6_multipath_hash_fields(net); + struct flow_keys keys, hash_keys; + + if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK)) + return 0; + + memset(&hash_keys, 0, sizeof(hash_keys)); + skb_flow_dissect_flow_keys(skb, &keys, FLOW_DISSECTOR_F_STOP_AT_ENCAP); + + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_IP) + hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_IP) + hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_IP_PROTO) + hash_keys.basic.ip_proto = keys.basic.ip_proto; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_FLOWLABEL) + hash_keys.tags.flow_label = keys.tags.flow_label; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_PORT) + hash_keys.ports.src = keys.ports.src; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT) + hash_keys.ports.dst = keys.ports.dst; + + *p_has_inner = !!(keys.control.flags & FLOW_DIS_ENCAPSULATION); + return fib_multipath_hash_from_keys(net, &hash_keys); +} + +static u32 rt6_multipath_custom_hash_inner(const struct net *net, + const struct sk_buff *skb, + bool has_inner) +{ + u32 hash_fields = ip6_multipath_hash_fields(net); + struct flow_keys keys, hash_keys; + + /* We assume the packet carries an encapsulation, but if none was + * encountered during dissection of the outer flow, then there is no + * point in calling the flow dissector again. + */ + if (!has_inner) + return 0; + + if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_MASK)) + return 0; + + memset(&hash_keys, 0, sizeof(hash_keys)); + skb_flow_dissect_flow_keys(skb, &keys, 0); + + if (!(keys.control.flags & FLOW_DIS_ENCAPSULATION)) + return 0; + + if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) { + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP) + hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP) + hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst; + } else if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) { + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP) + hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP) + hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL) + hash_keys.tags.flow_label = keys.tags.flow_label; + } + + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO) + hash_keys.basic.ip_proto = keys.basic.ip_proto; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT) + hash_keys.ports.src = keys.ports.src; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT) + hash_keys.ports.dst = keys.ports.dst; + + return fib_multipath_hash_from_keys(net, &hash_keys); } +static u32 rt6_multipath_custom_hash_skb(const struct net *net, + const struct sk_buff *skb) +{ + u32 mhash, mhash_inner; + bool has_inner = true; + + mhash = rt6_multipath_custom_hash_outer(net, skb, &has_inner); + mhash_inner = rt6_multipath_custom_hash_inner(net, skb, has_inner); + + return jhash_2words(mhash, mhash_inner, 0); +} + +static u32 rt6_multipath_custom_hash_fl6(const struct net *net, + const struct flowi6 *fl6) +{ + u32 hash_fields = ip6_multipath_hash_fields(net); + struct flow_keys hash_keys; + + if (!(hash_fields & FIB_MULTIPATH_HASH_FIELD_OUTER_MASK)) + return 0; + + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_IP) + hash_keys.addrs.v6addrs.src = fl6->saddr; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_IP) + hash_keys.addrs.v6addrs.dst = fl6->daddr; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_IP_PROTO) + hash_keys.basic.ip_proto = fl6->flowi6_proto; + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_FLOWLABEL) + hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6); + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_SRC_PORT) { + if (fl6->flowi6_flags & FLOWI_FLAG_ANY_SPORT) + hash_keys.ports.src = (__force __be16)get_random_u16(); + else + hash_keys.ports.src = fl6->fl6_sport; + } + if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT) + hash_keys.ports.dst = fl6->fl6_dport; + + return fib_multipath_hash_from_keys(net, &hash_keys); +} + +/* if skb is set it will be used and fl6 can be NULL */ +u32 rt6_multipath_hash(const struct net *net, const struct flowi6 *fl6, + const struct sk_buff *skb, struct flow_keys *flkeys) +{ + struct flow_keys hash_keys; + u32 mhash = 0; + + switch (ip6_multipath_hash_policy(net)) { + case 0: + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + if (skb) { + ip6_multipath_l3_keys(skb, &hash_keys, flkeys); + } else { + hash_keys.addrs.v6addrs.src = fl6->saddr; + hash_keys.addrs.v6addrs.dst = fl6->daddr; + hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6); + hash_keys.basic.ip_proto = fl6->flowi6_proto; + } + mhash = fib_multipath_hash_from_keys(net, &hash_keys); + break; + case 1: + if (skb) { + unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP; + struct flow_keys keys; + + /* short-circuit if we already have L4 hash present */ + if (skb->l4_hash) + return skb_get_hash_raw(skb) >> 1; + + memset(&hash_keys, 0, sizeof(hash_keys)); + + if (!flkeys) { + skb_flow_dissect_flow_keys(skb, &keys, flag); + flkeys = &keys; + } + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src; + hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst; + hash_keys.ports.src = flkeys->ports.src; + hash_keys.ports.dst = flkeys->ports.dst; + hash_keys.basic.ip_proto = flkeys->basic.ip_proto; + } else { + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + hash_keys.addrs.v6addrs.src = fl6->saddr; + hash_keys.addrs.v6addrs.dst = fl6->daddr; + if (fl6->flowi6_flags & FLOWI_FLAG_ANY_SPORT) + hash_keys.ports.src = (__force __be16)get_random_u16(); + else + hash_keys.ports.src = fl6->fl6_sport; + hash_keys.ports.dst = fl6->fl6_dport; + hash_keys.basic.ip_proto = fl6->flowi6_proto; + } + mhash = fib_multipath_hash_from_keys(net, &hash_keys); + break; + case 2: + memset(&hash_keys, 0, sizeof(hash_keys)); + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + if (skb) { + struct flow_keys keys; + + if (!flkeys) { + skb_flow_dissect_flow_keys(skb, &keys, 0); + flkeys = &keys; + } + + /* Inner can be v4 or v6 */ + if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) { + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; + hash_keys.addrs.v4addrs.src = flkeys->addrs.v4addrs.src; + hash_keys.addrs.v4addrs.dst = flkeys->addrs.v4addrs.dst; + } else if (flkeys->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) { + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + hash_keys.addrs.v6addrs.src = flkeys->addrs.v6addrs.src; + hash_keys.addrs.v6addrs.dst = flkeys->addrs.v6addrs.dst; + hash_keys.tags.flow_label = flkeys->tags.flow_label; + hash_keys.basic.ip_proto = flkeys->basic.ip_proto; + } else { + /* Same as case 0 */ + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + ip6_multipath_l3_keys(skb, &hash_keys, flkeys); + } + } else { + /* Same as case 0 */ + hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; + hash_keys.addrs.v6addrs.src = fl6->saddr; + hash_keys.addrs.v6addrs.dst = fl6->daddr; + hash_keys.tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6); + hash_keys.basic.ip_proto = fl6->flowi6_proto; + } + mhash = fib_multipath_hash_from_keys(net, &hash_keys); + break; + case 3: + if (skb) + mhash = rt6_multipath_custom_hash_skb(net, skb); + else + mhash = rt6_multipath_custom_hash_fl6(net, fl6); + break; + } + + return mhash >> 1; +} + +/* Called with rcu held */ void ip6_route_input(struct sk_buff *skb) { const struct ipv6hdr *iph = ipv6_hdr(skb); struct net *net = dev_net(skb->dev); - int flags = RT6_LOOKUP_F_HAS_SADDR; + int flags = RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_DST_NOREF; + struct ip_tunnel_info *tun_info; struct flowi6 fl6 = { .flowi6_iif = skb->dev->ifindex, .daddr = iph->daddr, @@ -978,70 +2626,113 @@ void ip6_route_input(struct sk_buff *skb) .flowi6_mark = skb->mark, .flowi6_proto = iph->nexthdr, }; + struct flow_keys *flkeys = NULL, _flkeys; + + tun_info = skb_tunnel_info(skb); + if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX)) + fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id; - skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags)); + if (fib6_rules_early_flow_dissect(net, skb, &fl6, &_flkeys)) + flkeys = &_flkeys; + + if (unlikely(fl6.flowi6_proto == IPPROTO_ICMPV6)) + fl6.mp_hash = rt6_multipath_hash(net, &fl6, skb, flkeys); + skb_dst_drop(skb); + skb_dst_set_noref(skb, ip6_route_input_lookup(net, skb->dev, + &fl6, skb, flags)); } -static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table, - struct flowi6 *fl6, int flags) +INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_output(struct net *net, + struct fib6_table *table, + struct flowi6 *fl6, + const struct sk_buff *skb, + int flags) { - return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags); + return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, skb, flags); } -struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk, - struct flowi6 *fl6) +static struct dst_entry *ip6_route_output_flags_noref(struct net *net, + const struct sock *sk, + struct flowi6 *fl6, + int flags) { - int flags = 0; + bool any_src; + + if (ipv6_addr_type(&fl6->daddr) & + (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) { + struct dst_entry *dst; + + /* This function does not take refcnt on the dst */ + dst = l3mdev_link_scope_lookup(net, fl6); + if (dst) + return dst; + } fl6->flowi6_iif = LOOPBACK_IFINDEX; - if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr)) + flags |= RT6_LOOKUP_F_DST_NOREF; + any_src = ipv6_addr_any(&fl6->saddr); + if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) || + (fl6->flowi6_oif && any_src)) flags |= RT6_LOOKUP_F_IFACE; - if (!ipv6_addr_any(&fl6->saddr)) + if (!any_src) flags |= RT6_LOOKUP_F_HAS_SADDR; else if (sk) - flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs); + flags |= rt6_srcprefs2flags(READ_ONCE(inet6_sk(sk)->srcprefs)); - return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output); + return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output); } -EXPORT_SYMBOL(ip6_route_output); +struct dst_entry *ip6_route_output_flags(struct net *net, + const struct sock *sk, + struct flowi6 *fl6, + int flags) +{ + struct dst_entry *dst; + struct rt6_info *rt6; + + rcu_read_lock(); + dst = ip6_route_output_flags_noref(net, sk, fl6, flags); + rt6 = dst_rt6_info(dst); + /* For dst cached in uncached_list, refcnt is already taken. */ + if (list_empty(&rt6->dst.rt_uncached) && !dst_hold_safe(dst)) { + dst = &net->ipv6.ip6_null_entry->dst; + dst_hold(dst); + } + rcu_read_unlock(); + + return dst; +} +EXPORT_SYMBOL_GPL(ip6_route_output_flags); struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig) { - struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig; + struct rt6_info *rt, *ort = dst_rt6_info(dst_orig); + struct net_device *loopback_dev = net->loopback_dev; struct dst_entry *new = NULL; - rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0); + rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, + DST_OBSOLETE_DEAD, 0); if (rt) { - new = &rt->dst; - - memset(new + 1, 0, sizeof(*rt) - sizeof(*new)); - rt6_init_peer(rt, net->ipv6.peers); + rt6_info_init(rt); + atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc); + new = &rt->dst; new->__use = 1; new->input = dst_discard; - new->output = dst_discard; + new->output = dst_discard_out; - if (dst_metrics_read_only(&ort->dst)) - new->_metrics = ort->dst._metrics; - else - dst_copy_metrics(new, &ort->dst); - rt->rt6i_idev = ort->rt6i_idev; - if (rt->rt6i_idev) - in6_dev_hold(rt->rt6i_idev); + dst_copy_metrics(new, &ort->dst); + rt->rt6i_idev = in6_dev_get(loopback_dev); rt->rt6i_gateway = ort->rt6i_gateway; - rt->rt6i_flags = ort->rt6i_flags; - rt->rt6i_metric = 0; + rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU; memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); #ifdef CONFIG_IPV6_SUBTREES memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); #endif - - dst_free(new); } dst_release(dst_orig); @@ -1052,41 +2743,97 @@ struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_ori * Destination cache support functions */ -static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie) +static bool fib6_check(struct fib6_info *f6i, u32 cookie) +{ + u32 rt_cookie = 0; + + if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie) + return false; + + if (fib6_check_expired(f6i)) + return false; + + return true; +} + +static struct dst_entry *rt6_check(struct rt6_info *rt, + struct fib6_info *from, + u32 cookie) +{ + u32 rt_cookie = 0; + + if (!from || !fib6_get_cookie_safe(from, &rt_cookie) || + rt_cookie != cookie) + return NULL; + + if (rt6_check_expired(rt)) + return NULL; + + return &rt->dst; +} + +static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, + struct fib6_info *from, + u32 cookie) { + if (!__rt6_check_expired(rt) && + READ_ONCE(rt->dst.obsolete) == DST_OBSOLETE_FORCE_CHK && + fib6_check(from, cookie)) + return &rt->dst; + return NULL; +} + +INDIRECT_CALLABLE_SCOPE struct dst_entry *ip6_dst_check(struct dst_entry *dst, + u32 cookie) +{ + struct dst_entry *dst_ret; + struct fib6_info *from; struct rt6_info *rt; - rt = (struct rt6_info *) dst; + rt = dst_rt6_info(dst); + + if (rt->sernum) + return rt6_is_valid(rt) ? dst : NULL; + + rcu_read_lock(); /* All IPV6 dsts are created with ->obsolete set to the value * DST_OBSOLETE_FORCE_CHK which forces validation calls down * into this function always. */ - if (rt->rt6i_genid != rt_genid(dev_net(rt->dst.dev))) - return NULL; - if (rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) - return dst; + from = rcu_dereference(rt->from); - return NULL; + if (from && (rt->rt6i_flags & RTF_PCPU || + unlikely(!list_empty(&rt->dst.rt_uncached)))) + dst_ret = rt6_dst_from_check(rt, from, cookie); + else + dst_ret = rt6_check(rt, from, cookie); + + rcu_read_unlock(); + + return dst_ret; } +EXPORT_INDIRECT_CALLABLE(ip6_dst_check); -static struct dst_entry *ip6_negative_advice(struct dst_entry *dst) +static void ip6_negative_advice(struct sock *sk, + struct dst_entry *dst) { - struct rt6_info *rt = (struct rt6_info *) dst; + struct rt6_info *rt = dst_rt6_info(dst); - if (rt) { - if (rt->rt6i_flags & RTF_CACHE) { - if (rt6_check_expired(rt)) { - ip6_del_rt(rt); - dst = NULL; - } - } else { - dst_release(dst); - dst = NULL; + if (rt->rt6i_flags & RTF_CACHE) { + rcu_read_lock(); + if (rt6_check_expired(rt)) { + /* rt/dst can not be destroyed yet, + * because of rcu_read_lock() + */ + sk_dst_reset(sk); + rt6_remove_exception_rt(rt); } + rcu_read_unlock(); + return; } - return dst; + sk_dst_reset(sk); } static void ip6_link_failure(struct sk_buff *skb) @@ -1095,106 +2842,414 @@ static void ip6_link_failure(struct sk_buff *skb) icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0); - rt = (struct rt6_info *) skb_dst(skb); + rt = dst_rt6_info(skb_dst(skb)); if (rt) { + rcu_read_lock(); if (rt->rt6i_flags & RTF_CACHE) { - dst_hold(&rt->dst); - if (ip6_del_rt(rt)) - dst_free(&rt->dst); - } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) { - rt->rt6i_node->fn_sernum = -1; + rt6_remove_exception_rt(rt); + } else { + struct fib6_info *from; + struct fib6_node *fn; + + from = rcu_dereference(rt->from); + if (from) { + fn = rcu_dereference(from->fib6_node); + if (fn && (rt->rt6i_flags & RTF_DEFAULT)) + WRITE_ONCE(fn->fn_sernum, -1); + } } + rcu_read_unlock(); } } -static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, - struct sk_buff *skb, u32 mtu) +static void rt6_update_expires(struct rt6_info *rt0, int timeout) { - struct rt6_info *rt6 = (struct rt6_info*)dst; + if (!(rt0->rt6i_flags & RTF_EXPIRES)) { + struct fib6_info *from; - dst_confirm(dst); - if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) { - struct net *net = dev_net(dst->dev); + rcu_read_lock(); + from = rcu_dereference(rt0->from); + if (from) + WRITE_ONCE(rt0->dst.expires, from->expires); + rcu_read_unlock(); + } - rt6->rt6i_flags |= RTF_MODIFIED; - if (mtu < IPV6_MIN_MTU) { - u32 features = dst_metric(dst, RTAX_FEATURES); - mtu = IPV6_MIN_MTU; - features |= RTAX_FEATURE_ALLFRAG; - dst_metric_set(dst, RTAX_FEATURES, features); + dst_set_expires(&rt0->dst, timeout); + rt0->rt6i_flags |= RTF_EXPIRES; +} + +static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu) +{ + struct net *net = dev_net(rt->dst.dev); + + dst_metric_set(&rt->dst, RTAX_MTU, mtu); + rt->rt6i_flags |= RTF_MODIFIED; + rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires); +} + +static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt) +{ + return !(rt->rt6i_flags & RTF_CACHE) && + (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from)); +} + +static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk, + const struct ipv6hdr *iph, u32 mtu, + bool confirm_neigh) +{ + const struct in6_addr *daddr, *saddr; + struct rt6_info *rt6 = dst_rt6_info(dst); + + /* Note: do *NOT* check dst_metric_locked(dst, RTAX_MTU) + * IPv6 pmtu discovery isn't optional, so 'mtu lock' cannot disable it. + * [see also comment in rt6_mtu_change_route()] + */ + + if (iph) { + daddr = &iph->daddr; + saddr = &iph->saddr; + } else if (sk) { + daddr = &sk->sk_v6_daddr; + saddr = &inet6_sk(sk)->saddr; + } else { + daddr = NULL; + saddr = NULL; + } + + if (confirm_neigh) + dst_confirm_neigh(dst, daddr); + + if (mtu < IPV6_MIN_MTU) + return; + if (mtu >= dst_mtu(dst)) + return; + + if (!rt6_cache_allowed_for_pmtu(rt6)) { + rt6_do_update_pmtu(rt6, mtu); + /* update rt6_ex->stamp for cache */ + if (rt6->rt6i_flags & RTF_CACHE) + rt6_update_exception_stamp_rt(rt6); + } else if (daddr) { + struct fib6_result res = {}; + struct rt6_info *nrt6; + + rcu_read_lock(); + res.f6i = rcu_dereference(rt6->from); + if (!res.f6i) + goto out_unlock; + + res.fib6_flags = res.f6i->fib6_flags; + res.fib6_type = res.f6i->fib6_type; + + if (res.f6i->nh) { + struct fib6_nh_match_arg arg = { + .dev = dst_dev_rcu(dst), + .gw = &rt6->rt6i_gateway, + }; + + nexthop_for_each_fib6_nh(res.f6i->nh, + fib6_nh_find_match, &arg); + + /* fib6_info uses a nexthop that does not have fib6_nh + * using the dst->dev + gw. Should be impossible. + */ + if (!arg.match) + goto out_unlock; + + res.nh = arg.match; + } else { + res.nh = res.f6i->fib6_nh; + } + + nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr); + if (nrt6) { + rt6_do_update_pmtu(nrt6, mtu); + if (rt6_insert_exception(nrt6, &res)) + dst_release_immediate(&nrt6->dst); } - dst_metric_set(dst, RTAX_MTU, mtu); - rt6_update_expires(rt6, net->ipv6.sysctl.ip6_rt_mtu_expires); +out_unlock: + rcu_read_unlock(); } } +static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, + struct sk_buff *skb, u32 mtu, + bool confirm_neigh) +{ + __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu, + confirm_neigh); +} + void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, - int oif, u32 mark) + int oif, u32 mark, kuid_t uid) { const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; struct dst_entry *dst; - struct flowi6 fl6; - - memset(&fl6, 0, sizeof(fl6)); - fl6.flowi6_oif = oif; - fl6.flowi6_mark = mark; - fl6.flowi6_flags = 0; - fl6.daddr = iph->daddr; - fl6.saddr = iph->saddr; - fl6.flowlabel = ip6_flowinfo(iph); + struct flowi6 fl6 = { + .flowi6_oif = oif, + .flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark), + .daddr = iph->daddr, + .saddr = iph->saddr, + .flowlabel = ip6_flowinfo(iph), + .flowi6_uid = uid, + }; dst = ip6_route_output(net, NULL, &fl6); if (!dst->error) - ip6_rt_update_pmtu(dst, NULL, skb, ntohl(mtu)); + __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu), true); dst_release(dst); } EXPORT_SYMBOL_GPL(ip6_update_pmtu); void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu) { - ip6_update_pmtu(skb, sock_net(sk), mtu, - sk->sk_bound_dev_if, sk->sk_mark); + int oif = sk->sk_bound_dev_if; + struct dst_entry *dst; + + if (!oif && skb->dev) + oif = l3mdev_master_ifindex(skb->dev); + + ip6_update_pmtu(skb, sock_net(sk), mtu, oif, READ_ONCE(sk->sk_mark), + sk_uid(sk)); + + dst = __sk_dst_get(sk); + if (!dst || !READ_ONCE(dst->obsolete) || + dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) + return; + + bh_lock_sock(sk); + if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) + ip6_datagram_dst_update(sk, false); + bh_unlock_sock(sk); } EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu); -void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark) +void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, + const struct flowi6 *fl6) { - const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; - struct dst_entry *dst; +#ifdef CONFIG_IPV6_SUBTREES + struct ipv6_pinfo *np = inet6_sk(sk); +#endif + + ip6_dst_store(sk, dst, + ipv6_addr_equal(&fl6->daddr, &sk->sk_v6_daddr), +#ifdef CONFIG_IPV6_SUBTREES + ipv6_addr_equal(&fl6->saddr, &np->saddr) ? + true : +#endif + false); +} + +static bool ip6_redirect_nh_match(const struct fib6_result *res, + struct flowi6 *fl6, + const struct in6_addr *gw, + struct rt6_info **ret) +{ + const struct fib6_nh *nh = res->nh; + + if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family || + fl6->flowi6_oif != nh->fib_nh_dev->ifindex) + return false; + + /* rt_cache's gateway might be different from its 'parent' + * in the case of an ip redirect. + * So we keep searching in the exception table if the gateway + * is different. + */ + if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) { + struct rt6_info *rt_cache; + + rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr); + if (rt_cache && + ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) { + *ret = rt_cache; + return true; + } + return false; + } + return true; +} + +struct fib6_nh_rd_arg { + struct fib6_result *res; + struct flowi6 *fl6; + const struct in6_addr *gw; + struct rt6_info **ret; +}; + +static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_rd_arg *arg = _arg; + + arg->res->nh = nh; + return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret); +} + +/* Handle redirects */ +struct ip6rd_flowi { struct flowi6 fl6; + struct in6_addr gateway; +}; + +INDIRECT_CALLABLE_SCOPE struct rt6_info *__ip6_route_redirect(struct net *net, + struct fib6_table *table, + struct flowi6 *fl6, + const struct sk_buff *skb, + int flags) +{ + struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6; + struct rt6_info *ret = NULL; + struct fib6_result res = {}; + struct fib6_nh_rd_arg arg = { + .res = &res, + .fl6 = fl6, + .gw = &rdfl->gateway, + .ret = &ret + }; + struct fib6_info *rt; + struct fib6_node *fn; - memset(&fl6, 0, sizeof(fl6)); - fl6.flowi6_oif = oif; - fl6.flowi6_mark = mark; - fl6.flowi6_flags = 0; - fl6.daddr = iph->daddr; - fl6.saddr = iph->saddr; - fl6.flowlabel = ip6_flowinfo(iph); + /* Get the "current" route for this destination and + * check if the redirect has come from appropriate router. + * + * RFC 4861 specifies that redirects should only be + * accepted if they come from the nexthop to the target. + * Due to the way the routes are chosen, this notion + * is a bit fuzzy and one might need to check all possible + * routes. + */ - dst = ip6_route_output(net, NULL, &fl6); - if (!dst->error) - rt6_do_redirect(dst, NULL, skb); + rcu_read_lock(); + fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); +restart: + for_each_fib6_node_rt_rcu(fn) { + res.f6i = rt; + if (fib6_check_expired(rt)) + continue; + if (rt->fib6_flags & RTF_REJECT) + break; + if (unlikely(rt->nh)) { + if (nexthop_is_blackhole(rt->nh)) + continue; + /* on match, res->nh is filled in and potentially ret */ + if (nexthop_for_each_fib6_nh(rt->nh, + fib6_nh_redirect_match, + &arg)) + goto out; + } else { + res.nh = rt->fib6_nh; + if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway, + &ret)) + goto out; + } + } + + if (!rt) + rt = net->ipv6.fib6_null_entry; + else if (rt->fib6_flags & RTF_REJECT) { + ret = net->ipv6.ip6_null_entry; + goto out; + } + + if (rt == net->ipv6.fib6_null_entry) { + fn = fib6_backtrack(fn, &fl6->saddr); + if (fn) + goto restart; + } + + res.f6i = rt; + res.nh = rt->fib6_nh; +out: + if (ret) { + ip6_hold_safe(net, &ret); + } else { + res.fib6_flags = res.f6i->fib6_flags; + res.fib6_type = res.f6i->fib6_type; + ret = ip6_create_rt_rcu(&res); + } + + rcu_read_unlock(); + + trace_fib6_table_lookup(net, &res, table, fl6); + return ret; +}; + +static struct dst_entry *ip6_route_redirect(struct net *net, + const struct flowi6 *fl6, + const struct sk_buff *skb, + const struct in6_addr *gateway) +{ + int flags = RT6_LOOKUP_F_HAS_SADDR; + struct ip6rd_flowi rdfl; + + rdfl.fl6 = *fl6; + rdfl.gateway = *gateway; + + return fib6_rule_lookup(net, &rdfl.fl6, skb, + flags, __ip6_route_redirect); +} + +void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, + kuid_t uid) +{ + const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; + struct dst_entry *dst; + struct flowi6 fl6 = { + .flowi6_iif = LOOPBACK_IFINDEX, + .flowi6_oif = oif, + .flowi6_mark = mark, + .daddr = iph->daddr, + .saddr = iph->saddr, + .flowlabel = ip6_flowinfo(iph), + .flowi6_uid = uid, + }; + + dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr); + rt6_do_redirect(dst, NULL, skb); dst_release(dst); } EXPORT_SYMBOL_GPL(ip6_redirect); +void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif) +{ + const struct ipv6hdr *iph = ipv6_hdr(skb); + const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb); + struct dst_entry *dst; + struct flowi6 fl6 = { + .flowi6_iif = LOOPBACK_IFINDEX, + .flowi6_oif = oif, + .daddr = msg->dest, + .saddr = iph->daddr, + .flowi6_uid = sock_net_uid(net, NULL), + }; + + dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr); + rt6_do_redirect(dst, NULL, skb); + dst_release(dst); +} + void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk) { - ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark); + ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, + READ_ONCE(sk->sk_mark), sk_uid(sk)); } EXPORT_SYMBOL_GPL(ip6_sk_redirect); static unsigned int ip6_default_advmss(const struct dst_entry *dst) { - struct net_device *dev = dst->dev; unsigned int mtu = dst_mtu(dst); - struct net *net = dev_net(dev); + struct net *net; mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr); + rcu_read_lock(); + + net = dst_dev_net_rcu(dst); if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss) mtu = net->ipv6.sysctl.ip6_rt_min_advmss; + rcu_read_unlock(); + /* * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. @@ -1206,28 +3261,53 @@ static unsigned int ip6_default_advmss(const struct dst_entry *dst) return mtu; } -static unsigned int ip6_mtu(const struct dst_entry *dst) +INDIRECT_CALLABLE_SCOPE unsigned int ip6_mtu(const struct dst_entry *dst) { + return ip6_dst_mtu_maybe_forward(dst, false); +} +EXPORT_INDIRECT_CALLABLE(ip6_mtu); + +/* MTU selection: + * 1. mtu on route is locked - use it + * 2. mtu from nexthop exception + * 3. mtu from egress device + * + * based on ip6_dst_mtu_forward and exception logic of + * rt6_find_cached_rt; called with rcu_read_lock + */ +u32 ip6_mtu_from_fib6(const struct fib6_result *res, + const struct in6_addr *daddr, + const struct in6_addr *saddr) +{ + const struct fib6_nh *nh = res->nh; + struct fib6_info *f6i = res->f6i; struct inet6_dev *idev; - unsigned int mtu = dst_metric_raw(dst, RTAX_MTU); + struct rt6_info *rt; + u32 mtu = 0; - if (mtu) - return mtu; + if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) { + mtu = f6i->fib6_pmtu; + if (mtu) + goto out; + } - mtu = IPV6_MIN_MTU; + rt = rt6_find_cached_rt(res, daddr, saddr); + if (unlikely(rt)) { + mtu = dst_metric_raw(&rt->dst, RTAX_MTU); + } else { + struct net_device *dev = nh->fib_nh_dev; - rcu_read_lock(); - idev = __in6_dev_get(dst->dev); - if (idev) - mtu = idev->cnf.mtu6; - rcu_read_unlock(); + mtu = IPV6_MIN_MTU; + idev = __in6_dev_get(dev); + if (idev) + mtu = max_t(u32, mtu, READ_ONCE(idev->cnf.mtu6)); + } - return mtu; + mtu = min_t(unsigned int, mtu, IP6_MAX_MTU); +out: + return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu); } -static struct dst_entry *icmp6_dst_gc_list; -static DEFINE_SPINLOCK(icmp6_dst_lock); - struct dst_entry *icmp6_dst_alloc(struct net_device *dev, struct flowi6 *fl6) { @@ -1239,27 +3319,25 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev, if (unlikely(!idev)) return ERR_PTR(-ENODEV); - rt = ip6_dst_alloc(net, dev, 0, NULL); + rt = ip6_dst_alloc(net, dev, 0); if (unlikely(!rt)) { in6_dev_put(idev); dst = ERR_PTR(-ENOMEM); goto out; } - rt->dst.flags |= DST_HOST; + rt->dst.input = ip6_input; rt->dst.output = ip6_output; - atomic_set(&rt->dst.__refcnt, 1); + rt->rt6i_gateway = fl6->daddr; rt->rt6i_dst.addr = fl6->daddr; rt->rt6i_dst.plen = 128; rt->rt6i_idev = idev; dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0); - spin_lock_bh(&icmp6_dst_lock); - rt->dst.next = icmp6_dst_gc_list; - icmp6_dst_gc_list = &rt->dst; - spin_unlock_bh(&icmp6_dst_lock); - - fib6_force_start_gc(net); + /* Add this dst into uncached_list so that rt6_disable_ip() can + * do proper release of the net_device + */ + rt6_uncached_list_add(rt); dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0); @@ -1267,117 +3345,250 @@ out: return dst; } -int icmp6_dst_gc(void) +static void ip6_dst_gc(struct dst_ops *ops) { - struct dst_entry *dst, **pprev; - int more = 0; + struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops); + int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval; + int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity; + int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout; + unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc; + unsigned int val; + int entries; - spin_lock_bh(&icmp6_dst_lock); - pprev = &icmp6_dst_gc_list; + if (time_after(rt_last_gc + rt_min_interval, jiffies)) + goto out; - while ((dst = *pprev) != NULL) { - if (!atomic_read(&dst->__refcnt)) { - *pprev = dst->next; - dst_free(dst); - } else { - pprev = &dst->next; - ++more; - } - } + fib6_run_gc(atomic_inc_return(&net->ipv6.ip6_rt_gc_expire), net, true); + entries = dst_entries_get_slow(ops); + if (entries < ops->gc_thresh) + atomic_set(&net->ipv6.ip6_rt_gc_expire, rt_gc_timeout >> 1); +out: + val = atomic_read(&net->ipv6.ip6_rt_gc_expire); + atomic_set(&net->ipv6.ip6_rt_gc_expire, val - (val >> rt_elasticity)); +} + +static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg, + const struct in6_addr *gw_addr, u32 tbid, + int flags, struct fib6_result *res) +{ + struct flowi6 fl6 = { + .flowi6_oif = cfg->fc_ifindex, + .daddr = *gw_addr, + .saddr = cfg->fc_prefsrc, + }; + struct fib6_table *table; + int err; + + table = fib6_get_table(net, tbid); + if (!table) + return -EINVAL; + + if (!ipv6_addr_any(&cfg->fc_prefsrc)) + flags |= RT6_LOOKUP_F_HAS_SADDR; + + flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE; - spin_unlock_bh(&icmp6_dst_lock); + err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags); + if (!err && res->f6i != net->ipv6.fib6_null_entry) + fib6_select_path(net, res, &fl6, cfg->fc_ifindex, + cfg->fc_ifindex != 0, NULL, flags); - return more; + return err; } -static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg), - void *arg) +static int ip6_route_check_nh_onlink(struct net *net, + struct fib6_config *cfg, + const struct net_device *dev, + struct netlink_ext_ack *extack) { - struct dst_entry *dst, **pprev; + u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN; + const struct in6_addr *gw_addr = &cfg->fc_gateway; + struct fib6_result res = {}; + int err; - spin_lock_bh(&icmp6_dst_lock); - pprev = &icmp6_dst_gc_list; - while ((dst = *pprev) != NULL) { - struct rt6_info *rt = (struct rt6_info *) dst; - if (func(rt, arg)) { - *pprev = dst->next; - dst_free(dst); - } else { - pprev = &dst->next; - } + err = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0, &res); + if (!err && !(res.fib6_flags & RTF_REJECT) && + /* ignore match if it is the default route */ + !ipv6_addr_any(&res.f6i->fib6_dst.addr) && + (res.fib6_type != RTN_UNICAST || dev != res.nh->fib_nh_dev)) { + NL_SET_ERR_MSG(extack, + "Nexthop has invalid gateway or device mismatch"); + err = -EINVAL; } - spin_unlock_bh(&icmp6_dst_lock); + + return err; } -static int ip6_dst_gc(struct dst_ops *ops) +static int ip6_route_check_nh(struct net *net, + struct fib6_config *cfg, + struct net_device **_dev, + netdevice_tracker *dev_tracker, + struct inet6_dev **idev) { - unsigned long now = jiffies; - struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops); - int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval; - int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size; - int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity; - int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout; - unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc; - int entries; + const struct in6_addr *gw_addr = &cfg->fc_gateway; + struct net_device *dev = _dev ? *_dev : NULL; + int flags = RT6_LOOKUP_F_IFACE; + struct fib6_result res = {}; + int err = -EHOSTUNREACH; + + if (cfg->fc_table) { + err = ip6_nh_lookup_table(net, cfg, gw_addr, + cfg->fc_table, flags, &res); + /* gw_addr can not require a gateway or resolve to a reject + * route. If a device is given, it must match the result. + */ + if (err || res.fib6_flags & RTF_REJECT || + res.nh->fib_nh_gw_family || + (dev && dev != res.nh->fib_nh_dev)) + err = -EHOSTUNREACH; + } - entries = dst_entries_get_fast(ops); - if (time_after(rt_last_gc + rt_min_interval, now) && - entries <= rt_max_size) - goto out; + if (err < 0) { + struct flowi6 fl6 = { + .flowi6_oif = cfg->fc_ifindex, + .daddr = *gw_addr, + }; + + err = fib6_lookup(net, cfg->fc_ifindex, &fl6, &res, flags); + if (err || res.fib6_flags & RTF_REJECT || + res.nh->fib_nh_gw_family) + err = -EHOSTUNREACH; - net->ipv6.ip6_rt_gc_expire++; - fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net); - net->ipv6.ip6_rt_last_gc = now; - entries = dst_entries_get_slow(ops); - if (entries < ops->gc_thresh) - net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1; -out: - net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity; - return entries > rt_max_size; + if (err) + return err; + + fib6_select_path(net, &res, &fl6, cfg->fc_ifindex, + cfg->fc_ifindex != 0, NULL, flags); + } + + err = 0; + if (dev) { + if (dev != res.nh->fib_nh_dev) + err = -EHOSTUNREACH; + } else { + *_dev = dev = res.nh->fib_nh_dev; + netdev_hold(dev, dev_tracker, GFP_ATOMIC); + *idev = in6_dev_get(dev); + } + + return err; } -int ip6_dst_hoplimit(struct dst_entry *dst) +static int ip6_validate_gw(struct net *net, struct fib6_config *cfg, + struct net_device **_dev, + netdevice_tracker *dev_tracker, + struct inet6_dev **idev, + struct netlink_ext_ack *extack) { - int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); - if (hoplimit == 0) { - struct net_device *dev = dst->dev; - struct inet6_dev *idev; + const struct in6_addr *gw_addr = &cfg->fc_gateway; + int gwa_type = ipv6_addr_type(gw_addr); + bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true; + const struct net_device *dev = *_dev; + bool need_addr_check = !dev; + int err = -EINVAL; + + /* if gw_addr is local we will fail to detect this in case + * address is still TENTATIVE (DAD in progress). rt6_lookup() + * will return already-added prefix route via interface that + * prefix route was assigned to, which might be non-loopback. + */ + if (dev && + ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) { + NL_SET_ERR_MSG(extack, "Gateway can not be a local address"); + goto out; + } + + if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) { + /* IPv6 strictly inhibits using not link-local + * addresses as nexthop address. + * Otherwise, router will not able to send redirects. + * It is very good, but in some (rare!) circumstances + * (SIT, PtP, NBMA NOARP links) it is handy to allow + * some exceptions. --ANK + * We allow IPv4-mapped nexthops to support RFC4798-type + * addressing + */ + if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) { + NL_SET_ERR_MSG(extack, "Invalid gateway address"); + goto out; + } rcu_read_lock(); - idev = __in6_dev_get(dev); - if (idev) - hoplimit = idev->cnf.hop_limit; + + if (cfg->fc_flags & RTNH_F_ONLINK) + err = ip6_route_check_nh_onlink(net, cfg, dev, extack); else - hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; + err = ip6_route_check_nh(net, cfg, _dev, dev_tracker, + idev); + rcu_read_unlock(); + + if (err) + goto out; + } + + /* reload in case device was changed */ + dev = *_dev; + + err = -EINVAL; + if (!dev) { + NL_SET_ERR_MSG(extack, "Egress device not specified"); + goto out; + } else if (dev->flags & IFF_LOOPBACK) { + NL_SET_ERR_MSG(extack, + "Egress device can not be loopback device for this route"); + goto out; + } + + /* if we did not check gw_addr above, do so now that the + * egress device has been resolved. + */ + if (need_addr_check && + ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) { + NL_SET_ERR_MSG(extack, "Gateway can not be a local address"); + goto out; } - return hoplimit; + + err = 0; +out: + return err; } -EXPORT_SYMBOL(ip6_dst_hoplimit); -/* - * - */ +static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type) +{ + if ((flags & RTF_REJECT) || + (dev && (dev->flags & IFF_LOOPBACK) && + !(addr_type & IPV6_ADDR_LOOPBACK) && + !(flags & (RTF_ANYCAST | RTF_LOCAL)))) + return true; + + return false; +} -int ip6_route_add(struct fib6_config *cfg) +int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh, + struct fib6_config *cfg, gfp_t gfp_flags, + struct netlink_ext_ack *extack) { - int err; - struct net *net = cfg->fc_nlinfo.nl_net; - struct rt6_info *rt = NULL; + netdevice_tracker *dev_tracker = &fib6_nh->fib_nh_dev_tracker; struct net_device *dev = NULL; struct inet6_dev *idev = NULL; - struct fib6_table *table; int addr_type; + int err; - if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128) - return -EINVAL; -#ifndef CONFIG_IPV6_SUBTREES - if (cfg->fc_src_len) - return -EINVAL; + fib6_nh->fib_nh_family = AF_INET6; +#ifdef CONFIG_IPV6_ROUTER_PREF + fib6_nh->last_probe = jiffies; #endif + if (cfg->fc_is_fdb) { + fib6_nh->fib_nh_gw6 = cfg->fc_gateway; + fib6_nh->fib_nh_gw_family = AF_INET6; + return 0; + } + + err = -ENODEV; if (cfg->fc_ifindex) { - err = -ENODEV; - dev = dev_get_by_index(net, cfg->fc_ifindex); + dev = netdev_get_by_index(net, cfg->fc_ifindex, + dev_tracker, gfp_flags); if (!dev) goto out; idev = in6_dev_get(dev); @@ -1385,10 +3596,201 @@ int ip6_route_add(struct fib6_config *cfg) goto out; } - if (cfg->fc_metric == 0) - cfg->fc_metric = IP6_RT_PRIO_USER; + if (cfg->fc_flags & RTNH_F_ONLINK) { + if (!dev) { + NL_SET_ERR_MSG(extack, + "Nexthop device required for onlink"); + goto out; + } + + if (!(dev->flags & IFF_UP)) { + NL_SET_ERR_MSG(extack, "Nexthop device is not up"); + err = -ENETDOWN; + goto out; + } + + fib6_nh->fib_nh_flags |= RTNH_F_ONLINK; + } + + fib6_nh->fib_nh_weight = 1; + + /* We cannot add true routes via loopback here, + * they would result in kernel looping; promote them to reject routes + */ + addr_type = ipv6_addr_type(&cfg->fc_dst); + if (fib6_is_reject(cfg->fc_flags, dev, addr_type)) { + /* hold loopback dev/idev if we haven't done so. */ + if (dev != net->loopback_dev) { + if (dev) { + netdev_put(dev, dev_tracker); + in6_dev_put(idev); + } + dev = net->loopback_dev; + netdev_hold(dev, dev_tracker, gfp_flags); + idev = in6_dev_get(dev); + if (!idev) { + err = -ENODEV; + goto out; + } + } + goto pcpu_alloc; + } + + if (cfg->fc_flags & RTF_GATEWAY) { + err = ip6_validate_gw(net, cfg, &dev, dev_tracker, + &idev, extack); + if (err) + goto out; + + fib6_nh->fib_nh_gw6 = cfg->fc_gateway; + fib6_nh->fib_nh_gw_family = AF_INET6; + } + + err = -ENODEV; + if (!dev) + goto out; + + if (!idev || idev->cnf.disable_ipv6) { + NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device"); + err = -EACCES; + goto out; + } + + if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) { + NL_SET_ERR_MSG(extack, "Nexthop device is not up"); + err = -ENETDOWN; + goto out; + } + + if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) && + !netif_carrier_ok(dev)) + fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN; + + err = fib_nh_common_init(net, &fib6_nh->nh_common, cfg->fc_encap, + cfg->fc_encap_type, cfg, gfp_flags, extack); + if (err) + goto out; + +pcpu_alloc: + fib6_nh->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags); + if (!fib6_nh->rt6i_pcpu) { + err = -ENOMEM; + goto out; + } + + fib6_nh->fib_nh_dev = dev; + fib6_nh->fib_nh_oif = dev->ifindex; + err = 0; +out: + if (idev) + in6_dev_put(idev); + + if (err) { + fib_nh_common_release(&fib6_nh->nh_common); + fib6_nh->nh_common.nhc_pcpu_rth_output = NULL; + fib6_nh->fib_nh_lws = NULL; + netdev_put(dev, dev_tracker); + } + + return err; +} + +void fib6_nh_release(struct fib6_nh *fib6_nh) +{ + struct rt6_exception_bucket *bucket; + + rcu_read_lock(); + + fib6_nh_flush_exceptions(fib6_nh, NULL); + bucket = fib6_nh_get_excptn_bucket(fib6_nh, NULL); + if (bucket) { + rcu_assign_pointer(fib6_nh->rt6i_exception_bucket, NULL); + kfree(bucket); + } + + rcu_read_unlock(); + + fib6_nh_release_dsts(fib6_nh); + free_percpu(fib6_nh->rt6i_pcpu); + + fib_nh_common_release(&fib6_nh->nh_common); +} + +void fib6_nh_release_dsts(struct fib6_nh *fib6_nh) +{ + int cpu; + + if (!fib6_nh->rt6i_pcpu) + return; + + for_each_possible_cpu(cpu) { + struct rt6_info *pcpu_rt, **ppcpu_rt; + + ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu); + pcpu_rt = xchg(ppcpu_rt, NULL); + if (pcpu_rt) { + dst_dev_put(&pcpu_rt->dst); + dst_release(&pcpu_rt->dst); + } + } +} + +static int fib6_config_validate(struct fib6_config *cfg, + struct netlink_ext_ack *extack) +{ + /* RTF_PCPU is an internal flag; can not be set by userspace */ + if (cfg->fc_flags & RTF_PCPU) { + NL_SET_ERR_MSG(extack, "Userspace can not set RTF_PCPU"); + goto errout; + } + + /* RTF_CACHE is an internal flag; can not be set by userspace */ + if (cfg->fc_flags & RTF_CACHE) { + NL_SET_ERR_MSG(extack, "Userspace can not set RTF_CACHE"); + goto errout; + } + + if (cfg->fc_type > RTN_MAX) { + NL_SET_ERR_MSG(extack, "Invalid route type"); + goto errout; + } + + if (cfg->fc_dst_len > 128) { + NL_SET_ERR_MSG(extack, "Invalid prefix length"); + goto errout; + } + +#ifdef CONFIG_IPV6_SUBTREES + if (cfg->fc_src_len > 128) { + NL_SET_ERR_MSG(extack, "Invalid source address length"); + goto errout; + } + + if (cfg->fc_nh_id && cfg->fc_src_len) { + NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing"); + goto errout; + } +#else + if (cfg->fc_src_len) { + NL_SET_ERR_MSG(extack, + "Specifying source address requires IPV6_SUBTREES to be enabled"); + goto errout; + } +#endif + return 0; +errout: + return -EINVAL; +} + +static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg, + gfp_t gfp_flags, + struct netlink_ext_ack *extack) +{ + struct net *net = cfg->fc_nlinfo.nl_net; + struct fib6_table *table; + struct fib6_info *rt; + int err; - err = -ENOBUFS; if (cfg->fc_nlinfo.nlh && !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) { table = fib6_get_table(net, cfg->fc_table); @@ -1399,275 +3801,412 @@ int ip6_route_add(struct fib6_config *cfg) } else { table = fib6_new_table(net, cfg->fc_table); } + if (!table) { + err = -ENOBUFS; + goto err; + } - if (!table) - goto out; - - rt = ip6_dst_alloc(net, NULL, DST_NOCOUNT, table); - + rt = fib6_info_alloc(gfp_flags, !cfg->fc_nh_id); if (!rt) { err = -ENOMEM; - goto out; + goto err; } + rt->fib6_metrics = ip_fib_metrics_init(cfg->fc_mx, cfg->fc_mx_len, + extack); + if (IS_ERR(rt->fib6_metrics)) { + err = PTR_ERR(rt->fib6_metrics); + goto free; + } + + if (cfg->fc_flags & RTF_ADDRCONF) + rt->dst_nocount = true; + if (cfg->fc_flags & RTF_EXPIRES) - rt6_set_expires(rt, jiffies + - clock_t_to_jiffies(cfg->fc_expires)); - else - rt6_clean_expires(rt); + fib6_set_expires(rt, jiffies + + clock_t_to_jiffies(cfg->fc_expires)); if (cfg->fc_protocol == RTPROT_UNSPEC) cfg->fc_protocol = RTPROT_BOOT; - rt->rt6i_protocol = cfg->fc_protocol; - - addr_type = ipv6_addr_type(&cfg->fc_dst); - if (addr_type & IPV6_ADDR_MULTICAST) - rt->dst.input = ip6_mc_input; - else if (cfg->fc_flags & RTF_LOCAL) - rt->dst.input = ip6_input; - else - rt->dst.input = ip6_forward; + rt->fib6_protocol = cfg->fc_protocol; + rt->fib6_table = table; + rt->fib6_metric = cfg->fc_metric; + rt->fib6_type = cfg->fc_type ? : RTN_UNICAST; + rt->fib6_flags = cfg->fc_flags & ~RTF_GATEWAY; - rt->dst.output = ip6_output; - - ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len); - rt->rt6i_dst.plen = cfg->fc_dst_len; - if (rt->rt6i_dst.plen == 128) - rt->dst.flags |= DST_HOST; + ipv6_addr_prefix(&rt->fib6_dst.addr, &cfg->fc_dst, cfg->fc_dst_len); + rt->fib6_dst.plen = cfg->fc_dst_len; - if (!(rt->dst.flags & DST_HOST) && cfg->fc_mx) { - u32 *metrics = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); - if (!metrics) { - err = -ENOMEM; - goto out; - } - dst_init_metrics(&rt->dst, metrics, 0); - } #ifdef CONFIG_IPV6_SUBTREES - ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len); - rt->rt6i_src.plen = cfg->fc_src_len; + ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len); + rt->fib6_src.plen = cfg->fc_src_len; #endif + return rt; +free: + kfree(rt); +err: + return ERR_PTR(err); +} - rt->rt6i_metric = cfg->fc_metric; +static int ip6_route_info_create_nh(struct fib6_info *rt, + struct fib6_config *cfg, + gfp_t gfp_flags, + struct netlink_ext_ack *extack) +{ + struct net *net = cfg->fc_nlinfo.nl_net; + struct fib6_nh *fib6_nh; + int err; - /* We cannot add true routes via loopback here, - they would result in kernel looping; promote them to reject routes - */ - if ((cfg->fc_flags & RTF_REJECT) || - (dev && (dev->flags & IFF_LOOPBACK) && - !(addr_type & IPV6_ADDR_LOOPBACK) && - !(cfg->fc_flags & RTF_LOCAL))) { - /* hold loopback dev/idev if we haven't done so. */ - if (dev != net->loopback_dev) { - if (dev) { - dev_put(dev); - in6_dev_put(idev); - } - dev = net->loopback_dev; - dev_hold(dev); - idev = in6_dev_get(dev); - if (!idev) { - err = -ENODEV; - goto out; - } + if (cfg->fc_nh_id) { + struct nexthop *nh; + + rcu_read_lock(); + + nh = nexthop_find_by_id(net, cfg->fc_nh_id); + if (!nh) { + err = -EINVAL; + NL_SET_ERR_MSG(extack, "Nexthop id does not exist"); + goto out_free; } - rt->dst.output = ip6_pkt_discard_out; - rt->dst.input = ip6_pkt_discard; - rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; - switch (cfg->fc_type) { - case RTN_BLACKHOLE: - rt->dst.error = -EINVAL; - break; - case RTN_PROHIBIT: - rt->dst.error = -EACCES; - break; - case RTN_THROW: - rt->dst.error = -EAGAIN; - break; - default: - rt->dst.error = -ENETUNREACH; - break; + + err = fib6_check_nexthop(nh, cfg, extack); + if (err) + goto out_free; + + if (!nexthop_get(nh)) { + NL_SET_ERR_MSG(extack, "Nexthop has been deleted"); + err = -ENOENT; + goto out_free; } - goto install_route; - } - if (cfg->fc_flags & RTF_GATEWAY) { - const struct in6_addr *gw_addr; - int gwa_type; - - gw_addr = &cfg->fc_gateway; - rt->rt6i_gateway = *gw_addr; - gwa_type = ipv6_addr_type(gw_addr); - - if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { - struct rt6_info *grt; - - /* IPv6 strictly inhibits using not link-local - addresses as nexthop address. - Otherwise, router will not able to send redirects. - It is very good, but in some (rare!) circumstances - (SIT, PtP, NBMA NOARP links) it is handy to allow - some exceptions. --ANK - */ - err = -EINVAL; - if (!(gwa_type & IPV6_ADDR_UNICAST)) - goto out; + rt->nh = nh; + fib6_nh = nexthop_fib6_nh(rt->nh); - grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1); + rcu_read_unlock(); + } else { + int addr_type; - err = -EHOSTUNREACH; - if (!grt) - goto out; - if (dev) { - if (dev != grt->dst.dev) { - ip6_rt_put(grt); - goto out; - } - } else { - dev = grt->dst.dev; - idev = grt->rt6i_idev; - dev_hold(dev); - in6_dev_hold(grt->rt6i_idev); - } - if (!(grt->rt6i_flags & RTF_GATEWAY)) - err = 0; - ip6_rt_put(grt); + err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack); + if (err) + goto out_release; - if (err) - goto out; - } - err = -EINVAL; - if (!dev || (dev->flags & IFF_LOOPBACK)) - goto out; - } + fib6_nh = rt->fib6_nh; - err = -ENODEV; - if (!dev) - goto out; + /* We cannot add true routes via loopback here, they would + * result in kernel looping; promote them to reject routes + */ + addr_type = ipv6_addr_type(&cfg->fc_dst); + if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev, + addr_type)) + rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP; + } if (!ipv6_addr_any(&cfg->fc_prefsrc)) { + struct net_device *dev = fib6_nh->fib_nh_dev; + if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) { + NL_SET_ERR_MSG(extack, "Invalid source address"); err = -EINVAL; - goto out; + goto out_release; } - rt->rt6i_prefsrc.addr = cfg->fc_prefsrc; - rt->rt6i_prefsrc.plen = 128; - } else - rt->rt6i_prefsrc.plen = 0; - - rt->rt6i_flags = cfg->fc_flags; - -install_route: - if (cfg->fc_mx) { - struct nlattr *nla; - int remaining; + rt->fib6_prefsrc.addr = cfg->fc_prefsrc; + rt->fib6_prefsrc.plen = 128; + } - nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { - int type = nla_type(nla); + return 0; +out_release: + fib6_info_release(rt); + return err; +out_free: + rcu_read_unlock(); + ip_fib_metrics_put(rt->fib6_metrics); + kfree(rt); + return err; +} - if (type) { - if (type > RTAX_MAX) { - err = -EINVAL; - goto out; - } +int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags, + struct netlink_ext_ack *extack) +{ + struct fib6_info *rt; + int err; - dst_metric_set(&rt->dst, type, nla_get_u32(nla)); - } - } - } + err = fib6_config_validate(cfg, extack); + if (err) + return err; - rt->dst.dev = dev; - rt->rt6i_idev = idev; - rt->rt6i_table = table; + rt = ip6_route_info_create(cfg, gfp_flags, extack); + if (IS_ERR(rt)) + return PTR_ERR(rt); - cfg->fc_nlinfo.nl_net = dev_net(dev); + err = ip6_route_info_create_nh(rt, cfg, gfp_flags, extack); + if (err) + return err; - return __ip6_ins_rt(rt, &cfg->fc_nlinfo); + err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack); + fib6_info_release(rt); -out: - if (dev) - dev_put(dev); - if (idev) - in6_dev_put(idev); - if (rt) - dst_free(&rt->dst); return err; } -static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info) +static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info) { - int err; + struct net *net = info->nl_net; struct fib6_table *table; - struct net *net = dev_net(rt->dst.dev); + int err; - if (rt == net->ipv6.ip6_null_entry) { + if (rt == net->ipv6.fib6_null_entry) { err = -ENOENT; goto out; } - table = rt->rt6i_table; - write_lock_bh(&table->tb6_lock); + table = rt->fib6_table; + spin_lock_bh(&table->tb6_lock); err = fib6_del(rt, info); - write_unlock_bh(&table->tb6_lock); + spin_unlock_bh(&table->tb6_lock); out: - ip6_rt_put(rt); + fib6_info_release(rt); return err; } -int ip6_del_rt(struct rt6_info *rt) +int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify) { struct nl_info info = { - .nl_net = dev_net(rt->dst.dev), + .nl_net = net, + .skip_notify = skip_notify }; + return __ip6_del_rt(rt, &info); } -static int ip6_route_del(struct fib6_config *cfg) +static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg) +{ + struct nl_info *info = &cfg->fc_nlinfo; + struct net *net = info->nl_net; + struct sk_buff *skb = NULL; + struct fib6_table *table; + int err = -ENOENT; + + if (rt == net->ipv6.fib6_null_entry) + goto out_put; + table = rt->fib6_table; + spin_lock_bh(&table->tb6_lock); + + if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) { + struct fib6_info *sibling, *next_sibling; + struct fib6_node *fn; + + /* prefer to send a single notification with all hops */ + skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any()); + if (skb) { + u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; + + if (rt6_fill_node(net, skb, rt, NULL, + NULL, NULL, 0, RTM_DELROUTE, + info->portid, seq, 0) < 0) { + kfree_skb(skb); + skb = NULL; + } else + info->skip_notify = 1; + } + + /* 'rt' points to the first sibling route. If it is not the + * leaf, then we do not need to send a notification. Otherwise, + * we need to check if the last sibling has a next route or not + * and emit a replace or delete notification, respectively. + */ + info->skip_notify_kernel = 1; + fn = rcu_dereference_protected(rt->fib6_node, + lockdep_is_held(&table->tb6_lock)); + if (rcu_access_pointer(fn->leaf) == rt) { + struct fib6_info *last_sibling, *replace_rt; + + last_sibling = list_last_entry(&rt->fib6_siblings, + struct fib6_info, + fib6_siblings); + replace_rt = rcu_dereference_protected( + last_sibling->fib6_next, + lockdep_is_held(&table->tb6_lock)); + if (replace_rt) + call_fib6_entry_notifiers_replace(net, + replace_rt); + else + call_fib6_multipath_entry_notifiers(net, + FIB_EVENT_ENTRY_DEL, + rt, rt->fib6_nsiblings, + NULL); + } + list_for_each_entry_safe(sibling, next_sibling, + &rt->fib6_siblings, + fib6_siblings) { + err = fib6_del(sibling, info); + if (err) + goto out_unlock; + } + } + + err = fib6_del(rt, info); +out_unlock: + spin_unlock_bh(&table->tb6_lock); +out_put: + fib6_info_release(rt); + + if (skb) { + rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE, + info->nlh, gfp_any()); + } + return err; +} + +static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg) +{ + int rc = -ESRCH; + + if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex) + goto out; + + if (cfg->fc_flags & RTF_GATEWAY && + !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway)) + goto out; + + rc = rt6_remove_exception_rt(rt); +out: + return rc; +} + +static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt, + struct fib6_nh *nh) +{ + struct fib6_result res = { + .f6i = rt, + .nh = nh, + }; + struct rt6_info *rt_cache; + + rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src); + if (rt_cache) + return __ip6_del_cached_rt(rt_cache, cfg); + + return 0; +} + +struct fib6_nh_del_cached_rt_arg { + struct fib6_config *cfg; + struct fib6_info *f6i; +}; + +static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_del_cached_rt_arg *arg = _arg; + int rc; + + rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh); + return rc != -ESRCH ? rc : 0; +} + +static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i) +{ + struct fib6_nh_del_cached_rt_arg arg = { + .cfg = cfg, + .f6i = f6i + }; + + return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg); +} + +static int ip6_route_del(struct fib6_config *cfg, + struct netlink_ext_ack *extack) { struct fib6_table *table; + struct fib6_info *rt; struct fib6_node *fn; - struct rt6_info *rt; int err = -ESRCH; table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table); - if (!table) + if (!table) { + NL_SET_ERR_MSG(extack, "FIB table does not exist"); return err; + } - read_lock_bh(&table->tb6_lock); + rcu_read_lock(); fn = fib6_locate(&table->tb6_root, &cfg->fc_dst, cfg->fc_dst_len, - &cfg->fc_src, cfg->fc_src_len); + &cfg->fc_src, cfg->fc_src_len, + !(cfg->fc_flags & RTF_CACHE)); if (fn) { - for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { + for_each_fib6_node_rt_rcu(fn) { + struct fib6_nh *nh; + + if (rt->nh && cfg->fc_nh_id && + rt->nh->id != cfg->fc_nh_id) + continue; + + if (cfg->fc_flags & RTF_CACHE) { + int rc = 0; + + if (rt->nh) { + rc = ip6_del_cached_rt_nh(cfg, rt); + } else if (cfg->fc_nh_id) { + continue; + } else { + nh = rt->fib6_nh; + rc = ip6_del_cached_rt(cfg, rt, nh); + } + if (rc != -ESRCH) { + rcu_read_unlock(); + return rc; + } + continue; + } + + if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric) + continue; + if (cfg->fc_protocol && + cfg->fc_protocol != rt->fib6_protocol) + continue; + + if (rt->nh) { + if (!fib6_info_hold_safe(rt)) + continue; + + err = __ip6_del_rt(rt, &cfg->fc_nlinfo); + break; + } + if (cfg->fc_nh_id) + continue; + + nh = rt->fib6_nh; if (cfg->fc_ifindex && - (!rt->dst.dev || - rt->dst.dev->ifindex != cfg->fc_ifindex)) + (!nh->fib_nh_dev || + nh->fib_nh_dev->ifindex != cfg->fc_ifindex)) continue; if (cfg->fc_flags & RTF_GATEWAY && - !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway)) + !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6)) continue; - if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric) + if (!fib6_info_hold_safe(rt)) continue; - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); - return __ip6_del_rt(rt, &cfg->fc_nlinfo); + /* if gateway was specified only delete the one hop */ + if (cfg->fc_flags & RTF_GATEWAY) + err = __ip6_del_rt(rt, &cfg->fc_nlinfo); + else + err = __ip6_del_rt_siblings(rt, cfg); + break; } } - read_unlock_bh(&table->tb6_lock); + rcu_read_unlock(); return err; } static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb) { - struct net *net = dev_net(skb->dev); struct netevent_redirect netevent; struct rt6_info *rt, *nrt = NULL; + struct fib6_result res = {}; struct ndisc_options ndopts; struct inet6_dev *in6_dev; struct neighbour *neigh; @@ -1702,7 +4241,8 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu in6_dev = __in6_dev_get(skb->dev); if (!in6_dev) return; - if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) + if (READ_ONCE(in6_dev->cnf.forwarding) || + !READ_ONCE(in6_dev->cnf.accept_redirects)) return; /* RFC2461 8.1: @@ -1710,7 +4250,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu * first-hop router for the specified ICMP Destination Address. */ - if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) { + if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) { net_dbg_ratelimited("rt6_redirect: invalid ND options\n"); return; } @@ -1725,8 +4265,8 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu } } - rt = (struct rt6_info *) dst; - if (rt == net->ipv6.ip6_null_entry) { + rt = dst_rt6_info(dst); + if (rt->rt6i_flags & RTF_REJECT) { net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n"); return; } @@ -1735,7 +4275,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu * Look, redirects are sent only in response to data packets, * so that this nexthop apparently is reachable. --ANK */ - dst_confirm(&rt->dst); + dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr); neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1); if (!neigh) @@ -1745,14 +4285,40 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu * We have finally decided to accept it. */ - neigh_update(neigh, lladdr, NUD_STALE, + ndisc_update(skb->dev, neigh, lladdr, NUD_STALE, NEIGH_UPDATE_F_WEAK_OVERRIDE| NEIGH_UPDATE_F_OVERRIDE| (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER| - NEIGH_UPDATE_F_ISROUTER)) - ); + NEIGH_UPDATE_F_ISROUTER)), + NDISC_REDIRECT, &ndopts); + + rcu_read_lock(); + res.f6i = rcu_dereference(rt->from); + if (!res.f6i) + goto out; + + if (res.f6i->nh) { + struct fib6_nh_match_arg arg = { + .dev = dst_dev_rcu(dst), + .gw = &rt->rt6i_gateway, + }; + + nexthop_for_each_fib6_nh(res.f6i->nh, + fib6_nh_find_match, &arg); + + /* fib6_info uses a nexthop that does not have fib6_nh + * using the dst->dev. Should be impossible + */ + if (!arg.match) + goto out; + res.nh = arg.match; + } else { + res.nh = res.f6i->fib6_nh; + } - nrt = ip6_rt_copy(rt, &msg->dest); + res.fib6_flags = res.f6i->fib6_flags; + res.fib6_type = res.f6i->fib6_type; + nrt = ip6_rt_cache_alloc(&res, &msg->dest, NULL); if (!nrt) goto out; @@ -1762,8 +4328,11 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key; - if (ip6_ins_rt(nrt)) + /* rt6_insert_exception() will take care of duplicated exceptions */ + if (rt6_insert_exception(nrt, &res)) { + dst_release_immediate(&nrt->dst); goto out; + } netevent.old = &rt->dst; netevent.new = &nrt->dst; @@ -1771,106 +4340,72 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu netevent.neigh = neigh; call_netevent_notifiers(NETEVENT_REDIRECT, &netevent); - if (rt->rt6i_flags & RTF_CACHE) { - rt = (struct rt6_info *) dst_clone(&rt->dst); - ip6_del_rt(rt); - } - out: + rcu_read_unlock(); neigh_release(neigh); } -/* - * Misc support functions - */ - -static struct rt6_info *ip6_rt_copy(struct rt6_info *ort, - const struct in6_addr *dest) -{ - struct net *net = dev_net(ort->dst.dev); - struct rt6_info *rt = ip6_dst_alloc(net, ort->dst.dev, 0, - ort->rt6i_table); - - if (rt) { - rt->dst.input = ort->dst.input; - rt->dst.output = ort->dst.output; - rt->dst.flags |= DST_HOST; - - rt->rt6i_dst.addr = *dest; - rt->rt6i_dst.plen = 128; - dst_copy_metrics(&rt->dst, &ort->dst); - rt->dst.error = ort->dst.error; - rt->rt6i_idev = ort->rt6i_idev; - if (rt->rt6i_idev) - in6_dev_hold(rt->rt6i_idev); - rt->dst.lastuse = jiffies; - - rt->rt6i_gateway = ort->rt6i_gateway; - rt->rt6i_flags = ort->rt6i_flags; - if ((ort->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) == - (RTF_DEFAULT | RTF_ADDRCONF)) - rt6_set_from(rt, ort); - rt->rt6i_metric = 0; - -#ifdef CONFIG_IPV6_SUBTREES - memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); -#endif - memcpy(&rt->rt6i_prefsrc, &ort->rt6i_prefsrc, sizeof(struct rt6key)); - rt->rt6i_table = ort->rt6i_table; - } - return rt; -} - #ifdef CONFIG_IPV6_ROUTE_INFO -static struct rt6_info *rt6_get_route_info(struct net *net, +static struct fib6_info *rt6_get_route_info(struct net *net, const struct in6_addr *prefix, int prefixlen, - const struct in6_addr *gwaddr, int ifindex) + const struct in6_addr *gwaddr, + struct net_device *dev) { + u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO; + int ifindex = dev->ifindex; struct fib6_node *fn; - struct rt6_info *rt = NULL; + struct fib6_info *rt = NULL; struct fib6_table *table; - table = fib6_get_table(net, RT6_TABLE_INFO); + table = fib6_get_table(net, tb_id); if (!table) return NULL; - read_lock_bh(&table->tb6_lock); - fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0); + rcu_read_lock(); + fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true); if (!fn) goto out; - for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { - if (rt->dst.dev->ifindex != ifindex) + for_each_fib6_node_rt_rcu(fn) { + /* these routes do not use nexthops */ + if (rt->nh) continue; - if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY)) + if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex) continue; - if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr)) + if (!(rt->fib6_flags & RTF_ROUTEINFO) || + !rt->fib6_nh->fib_nh_gw_family) + continue; + if (!ipv6_addr_equal(&rt->fib6_nh->fib_nh_gw6, gwaddr)) + continue; + if (!fib6_info_hold_safe(rt)) continue; - dst_hold(&rt->dst); break; } out: - read_unlock_bh(&table->tb6_lock); + rcu_read_unlock(); return rt; } -static struct rt6_info *rt6_add_route_info(struct net *net, +static struct fib6_info *rt6_add_route_info(struct net *net, const struct in6_addr *prefix, int prefixlen, - const struct in6_addr *gwaddr, int ifindex, + const struct in6_addr *gwaddr, + struct net_device *dev, unsigned int pref) { struct fib6_config cfg = { - .fc_table = RT6_TABLE_INFO, .fc_metric = IP6_RT_PRIO_USER, - .fc_ifindex = ifindex, + .fc_ifindex = dev->ifindex, .fc_dst_len = prefixlen, .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO | RTF_UP | RTF_PREF(pref), + .fc_protocol = RTPROT_RA, + .fc_type = RTN_UNICAST, .fc_nlinfo.portid = 0, .fc_nlinfo.nlh = NULL, .fc_nlinfo.nl_net = net, }; + cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO; cfg.fc_dst = *prefix; cfg.fc_gateway = *gwaddr; @@ -1878,136 +4413,169 @@ static struct rt6_info *rt6_add_route_info(struct net *net, if (!prefixlen) cfg.fc_flags |= RTF_DEFAULT; - ip6_route_add(&cfg); + ip6_route_add(&cfg, GFP_ATOMIC, NULL); - return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex); + return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev); } #endif -struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev) +struct fib6_info *rt6_get_dflt_router(struct net *net, + const struct in6_addr *addr, + struct net_device *dev) { - struct rt6_info *rt; + u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT; + struct fib6_info *rt; struct fib6_table *table; - table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT); + table = fib6_get_table(net, tb_id); if (!table) return NULL; - read_lock_bh(&table->tb6_lock); - for (rt = table->tb6_root.leaf; rt; rt=rt->dst.rt6_next) { - if (dev == rt->dst.dev && - ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && - ipv6_addr_equal(&rt->rt6i_gateway, addr)) + rcu_read_lock(); + for_each_fib6_node_rt_rcu(&table->tb6_root) { + struct fib6_nh *nh; + + /* RA routes do not use nexthops */ + if (rt->nh) + continue; + + nh = rt->fib6_nh; + if (dev == nh->fib_nh_dev && + ((rt->fib6_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && + ipv6_addr_equal(&nh->fib_nh_gw6, addr)) break; } - if (rt) - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); + if (rt && !fib6_info_hold_safe(rt)) + rt = NULL; + rcu_read_unlock(); return rt; } -struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, +struct fib6_info *rt6_add_dflt_router(struct net *net, + const struct in6_addr *gwaddr, struct net_device *dev, - unsigned int pref) + unsigned int pref, + u32 defrtr_usr_metric, + int lifetime) { struct fib6_config cfg = { - .fc_table = RT6_TABLE_DFLT, - .fc_metric = IP6_RT_PRIO_USER, + .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT, + .fc_metric = defrtr_usr_metric, .fc_ifindex = dev->ifindex, .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT | RTF_UP | RTF_EXPIRES | RTF_PREF(pref), + .fc_protocol = RTPROT_RA, + .fc_type = RTN_UNICAST, .fc_nlinfo.portid = 0, .fc_nlinfo.nlh = NULL, - .fc_nlinfo.nl_net = dev_net(dev), + .fc_nlinfo.nl_net = net, + .fc_expires = jiffies_to_clock_t(lifetime * HZ), }; cfg.fc_gateway = *gwaddr; - ip6_route_add(&cfg); + if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) { + struct fib6_table *table; + + table = fib6_get_table(dev_net(dev), cfg.fc_table); + if (table) + table->flags |= RT6_TABLE_HAS_DFLT_ROUTER; + } - return rt6_get_dflt_router(gwaddr, dev); + return rt6_get_dflt_router(net, gwaddr, dev); +} + +static void __rt6_purge_dflt_routers(struct net *net, + struct fib6_table *table) +{ + struct fib6_info *rt; + +restart: + rcu_read_lock(); + for_each_fib6_node_rt_rcu(&table->tb6_root) { + struct net_device *dev = fib6_info_nh_dev(rt); + struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL; + + if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) && + (!idev || idev->cnf.accept_ra != 2) && + fib6_info_hold_safe(rt)) { + rcu_read_unlock(); + ip6_del_rt(net, rt, false); + goto restart; + } + } + rcu_read_unlock(); + + table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER; } void rt6_purge_dflt_routers(struct net *net) { - struct rt6_info *rt; struct fib6_table *table; + struct hlist_head *head; + unsigned int h; - /* NOTE: Keep consistent with rt6_get_dflt_router */ - table = fib6_get_table(net, RT6_TABLE_DFLT); - if (!table) - return; + rcu_read_lock(); -restart: - read_lock_bh(&table->tb6_lock); - for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) { - if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) && - (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) { - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); - ip6_del_rt(rt); - goto restart; + for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { + head = &net->ipv6.fib_table_hash[h]; + hlist_for_each_entry_rcu(table, head, tb6_hlist) { + if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER) + __rt6_purge_dflt_routers(net, table); } } - read_unlock_bh(&table->tb6_lock); + + rcu_read_unlock(); } static void rtmsg_to_fib6_config(struct net *net, struct in6_rtmsg *rtmsg, struct fib6_config *cfg) { - memset(cfg, 0, sizeof(*cfg)); - - cfg->fc_table = RT6_TABLE_MAIN; - cfg->fc_ifindex = rtmsg->rtmsg_ifindex; - cfg->fc_metric = rtmsg->rtmsg_metric; - cfg->fc_expires = rtmsg->rtmsg_info; - cfg->fc_dst_len = rtmsg->rtmsg_dst_len; - cfg->fc_src_len = rtmsg->rtmsg_src_len; - cfg->fc_flags = rtmsg->rtmsg_flags; + *cfg = (struct fib6_config){ + .fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ? + : RT6_TABLE_MAIN, + .fc_ifindex = rtmsg->rtmsg_ifindex, + .fc_metric = rtmsg->rtmsg_metric, + .fc_expires = rtmsg->rtmsg_info, + .fc_dst_len = rtmsg->rtmsg_dst_len, + .fc_src_len = rtmsg->rtmsg_src_len, + .fc_flags = rtmsg->rtmsg_flags, + .fc_type = rtmsg->rtmsg_type, - cfg->fc_nlinfo.nl_net = net; + .fc_nlinfo.nl_net = net, - cfg->fc_dst = rtmsg->rtmsg_dst; - cfg->fc_src = rtmsg->rtmsg_src; - cfg->fc_gateway = rtmsg->rtmsg_gateway; + .fc_dst = rtmsg->rtmsg_dst, + .fc_src = rtmsg->rtmsg_src, + .fc_gateway = rtmsg->rtmsg_gateway, + }; } -int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) +int ipv6_route_ioctl(struct net *net, unsigned int cmd, struct in6_rtmsg *rtmsg) { struct fib6_config cfg; - struct in6_rtmsg rtmsg; int err; - switch(cmd) { - case SIOCADDRT: /* Add a route */ - case SIOCDELRT: /* Delete a route */ - if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) - return -EPERM; - err = copy_from_user(&rtmsg, arg, - sizeof(struct in6_rtmsg)); - if (err) - return -EFAULT; - - rtmsg_to_fib6_config(net, &rtmsg, &cfg); + if (cmd != SIOCADDRT && cmd != SIOCDELRT) + return -EINVAL; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + return -EPERM; - rtnl_lock(); - switch (cmd) { - case SIOCADDRT: - err = ip6_route_add(&cfg); - break; - case SIOCDELRT: - err = ip6_route_del(&cfg); - break; - default: - err = -EINVAL; - } - rtnl_unlock(); + rtmsg_to_fib6_config(net, rtmsg, &cfg); - return err; + switch (cmd) { + case SIOCADDRT: + /* Only do the default setting of fc_metric in route adding */ + if (cfg.fc_metric == 0) + cfg.fc_metric = IP6_RT_PRIO_USER; + err = ip6_route_add(&cfg, GFP_KERNEL, NULL); + break; + case SIOCDELRT: + err = ip6_route_del(&cfg, NULL); + break; } - return -EINVAL; + return err; } /* @@ -2016,24 +4584,41 @@ int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes) { - int type; struct dst_entry *dst = skb_dst(skb); + struct net_device *dev = dst_dev(dst); + struct net *net = dev_net(dev); + struct inet6_dev *idev; + SKB_DR(reason); + int type; + + if (netif_is_l3_master(skb->dev) || + dev == net->loopback_dev) + idev = __in6_dev_get_safely(dev_get_by_index_rcu(net, IP6CB(skb)->iif)); + else + idev = ip6_dst_idev(dst); + switch (ipstats_mib_noroutes) { case IPSTATS_MIB_INNOROUTES: type = ipv6_addr_type(&ipv6_hdr(skb)->daddr); if (type == IPV6_ADDR_ANY) { - IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), - IPSTATS_MIB_INADDRERRORS); + SKB_DR_SET(reason, IP_INADDRERRORS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS); break; } - /* FALLTHROUGH */ + SKB_DR_SET(reason, IP_INNOROUTES); + fallthrough; case IPSTATS_MIB_OUTNOROUTES: - IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), - ipstats_mib_noroutes); + SKB_DR_OR(reason, IP_OUTNOROUTES); + IP6_INC_STATS(net, idev, ipstats_mib_noroutes); break; } + + /* Start over by dropping the dst for l3mdev case */ + if (netif_is_l3_master(skb->dev)) + skb_dst_drop(skb); + icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0); - kfree_skb(skb); + kfree_skb_reason(skb, reason); return 0; } @@ -2042,99 +4627,91 @@ static int ip6_pkt_discard(struct sk_buff *skb) return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES); } -static int ip6_pkt_discard_out(struct sk_buff *skb) +static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb) { - skb->dev = skb_dst(skb)->dev; + skb->dev = skb_dst_dev(skb); return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES); } -#ifdef CONFIG_IPV6_MULTIPLE_TABLES - static int ip6_pkt_prohibit(struct sk_buff *skb) { return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES); } -static int ip6_pkt_prohibit_out(struct sk_buff *skb) +static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb) { - skb->dev = skb_dst(skb)->dev; + skb->dev = skb_dst_dev(skb); return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); } -#endif - /* * Allocate a dst for local (unicast / anycast) address. */ -struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, - const struct in6_addr *addr, - bool anycast) +struct fib6_info *addrconf_f6i_alloc(struct net *net, + struct inet6_dev *idev, + const struct in6_addr *addr, + bool anycast, gfp_t gfp_flags, + struct netlink_ext_ack *extack) { - struct net *net = dev_net(idev->dev); - struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev, 0, NULL); + struct fib6_config cfg = { + .fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL, + .fc_ifindex = idev->dev->ifindex, + .fc_flags = RTF_UP | RTF_NONEXTHOP, + .fc_dst = *addr, + .fc_dst_len = 128, + .fc_protocol = RTPROT_KERNEL, + .fc_nlinfo.nl_net = net, + .fc_ignore_dev_down = true, + }; + struct fib6_info *f6i; + int err; - if (!rt) { - net_warn_ratelimited("Maximum number of routes reached, consider increasing route/max_size\n"); - return ERR_PTR(-ENOMEM); + if (anycast) { + cfg.fc_type = RTN_ANYCAST; + cfg.fc_flags |= RTF_ANYCAST; + } else { + cfg.fc_type = RTN_LOCAL; + cfg.fc_flags |= RTF_LOCAL; } - in6_dev_hold(idev); + f6i = ip6_route_info_create(&cfg, gfp_flags, extack); + if (IS_ERR(f6i)) + return f6i; - rt->dst.flags |= DST_HOST; - rt->dst.input = ip6_input; - rt->dst.output = ip6_output; - rt->rt6i_idev = idev; + err = ip6_route_info_create_nh(f6i, &cfg, gfp_flags, extack); + if (err) + return ERR_PTR(err); - rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP; - if (anycast) - rt->rt6i_flags |= RTF_ANYCAST; - else - rt->rt6i_flags |= RTF_LOCAL; + f6i->dst_nocount = true; - rt->rt6i_dst.addr = *addr; - rt->rt6i_dst.plen = 128; - rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL); - - atomic_set(&rt->dst.__refcnt, 1); - - return rt; -} + if (!anycast && + (READ_ONCE(net->ipv6.devconf_all->disable_policy) || + READ_ONCE(idev->cnf.disable_policy))) + f6i->dst_nopolicy = true; -int ip6_route_get_saddr(struct net *net, - struct rt6_info *rt, - const struct in6_addr *daddr, - unsigned int prefs, - struct in6_addr *saddr) -{ - struct inet6_dev *idev = ip6_dst_idev((struct dst_entry*)rt); - int err = 0; - if (rt->rt6i_prefsrc.plen) - *saddr = rt->rt6i_prefsrc.addr; - else - err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, - daddr, prefs, saddr); - return err; + return f6i; } /* remove deleted ip from prefsrc entries */ struct arg_dev_net_ip { - struct net_device *dev; struct net *net; struct in6_addr *addr; }; -static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg) +static int fib6_remove_prefsrc(struct fib6_info *rt, void *arg) { - struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev; struct net *net = ((struct arg_dev_net_ip *)arg)->net; struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr; - if (((void *)rt->dst.dev == dev || !dev) && - rt != net->ipv6.ip6_null_entry && - ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) { + if (!rt->nh && + rt != net->ipv6.fib6_null_entry && + ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr) && + !ipv6_chk_addr(net, addr, rt->fib6_nh->fib_nh_dev, 0)) { + spin_lock_bh(&rt6_exception_lock); /* remove prefsrc entry */ - rt->rt6i_prefsrc.plen = 0; + rt->fib6_prefsrc.plen = 0; + spin_unlock_bh(&rt6_exception_lock); } return 0; } @@ -2143,47 +4720,329 @@ void rt6_remove_prefsrc(struct inet6_ifaddr *ifp) { struct net *net = dev_net(ifp->idev->dev); struct arg_dev_net_ip adni = { - .dev = ifp->idev->dev, .net = net, .addr = &ifp->addr, }; - fib6_clean_all(net, fib6_remove_prefsrc, 0, &adni); + fib6_clean_all(net, fib6_remove_prefsrc, &adni); } -struct arg_dev_net { - struct net_device *dev; - struct net *net; -}; +#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT) -static int fib6_ifdown(struct rt6_info *rt, void *arg) +/* Remove routers and update dst entries when gateway turn into host. */ +static int fib6_clean_tohost(struct fib6_info *rt, void *arg) { - const struct arg_dev_net *adn = arg; - const struct net_device *dev = adn->dev; + struct in6_addr *gateway = (struct in6_addr *)arg; + struct fib6_nh *nh; - if ((rt->dst.dev == dev || !dev) && - rt != adn->net->ipv6.ip6_null_entry) + /* RA routes do not use nexthops */ + if (rt->nh) + return 0; + + nh = rt->fib6_nh; + if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) && + nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6)) return -1; + /* Further clean up cached routes in exception table. + * This is needed because cached route may have a different + * gateway than its 'parent' in the case of an ip redirect. + */ + fib6_nh_exceptions_clean_tohost(nh, gateway); + + return 0; +} + +void rt6_clean_tohost(struct net *net, struct in6_addr *gateway) +{ + fib6_clean_all(net, fib6_clean_tohost, gateway); +} + +struct arg_netdev_event { + const struct net_device *dev; + union { + unsigned char nh_flags; + unsigned long event; + }; +}; + +static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt) +{ + struct fib6_info *iter; + struct fib6_node *fn; + + fn = rcu_dereference_protected(rt->fib6_node, + lockdep_is_held(&rt->fib6_table->tb6_lock)); + iter = rcu_dereference_protected(fn->leaf, + lockdep_is_held(&rt->fib6_table->tb6_lock)); + while (iter) { + if (iter->fib6_metric == rt->fib6_metric && + rt6_qualify_for_ecmp(iter)) + return iter; + iter = rcu_dereference_protected(iter->fib6_next, + lockdep_is_held(&rt->fib6_table->tb6_lock)); + } + + return NULL; +} + +/* only called for fib entries with builtin fib6_nh */ +static bool rt6_is_dead(const struct fib6_info *rt) +{ + if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD || + (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN && + ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev))) + return true; + + return false; +} + +static int rt6_multipath_total_weight(const struct fib6_info *rt) +{ + struct fib6_info *iter; + int total = 0; + + if (!rt6_is_dead(rt)) + total += rt->fib6_nh->fib_nh_weight; + + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) { + if (!rt6_is_dead(iter)) + total += iter->fib6_nh->fib_nh_weight; + } + + return total; +} + +static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total) +{ + int upper_bound = -1; + + if (!rt6_is_dead(rt)) { + *weight += rt->fib6_nh->fib_nh_weight; + upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31, + total) - 1; + } + atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound); +} + +static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total) +{ + struct fib6_info *iter; + int weight = 0; + + rt6_upper_bound_set(rt, &weight, total); + + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) + rt6_upper_bound_set(iter, &weight, total); +} + +void rt6_multipath_rebalance(struct fib6_info *rt) +{ + struct fib6_info *first; + int total; + + /* In case the entire multipath route was marked for flushing, + * then there is no need to rebalance upon the removal of every + * sibling route. + */ + if (!rt->fib6_nsiblings || rt->should_flush) + return; + + /* During lookup routes are evaluated in order, so we need to + * make sure upper bounds are assigned from the first sibling + * onwards. + */ + first = rt6_multipath_first_sibling(rt); + if (WARN_ON_ONCE(!first)) + return; + + total = rt6_multipath_total_weight(first); + rt6_multipath_upper_bound_set(first, total); +} + +static int fib6_ifup(struct fib6_info *rt, void *p_arg) +{ + const struct arg_netdev_event *arg = p_arg; + struct net *net = dev_net(arg->dev); + + if (rt != net->ipv6.fib6_null_entry && !rt->nh && + rt->fib6_nh->fib_nh_dev == arg->dev) { + rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags; + fib6_update_sernum_upto_root(net, rt); + rt6_multipath_rebalance(rt); + } + return 0; } -void rt6_ifdown(struct net *net, struct net_device *dev) +void rt6_sync_up(struct net_device *dev, unsigned char nh_flags) { - struct arg_dev_net adn = { + struct arg_netdev_event arg = { .dev = dev, - .net = net, + { + .nh_flags = nh_flags, + }, }; - fib6_clean_all(net, fib6_ifdown, 0, &adn); - icmp6_clean_all(fib6_ifdown, &adn); + if (nh_flags & RTNH_F_DEAD && netif_carrier_ok(dev)) + arg.nh_flags |= RTNH_F_LINKDOWN; + + fib6_clean_all(dev_net(dev), fib6_ifup, &arg); +} + +/* only called for fib entries with inline fib6_nh */ +static bool rt6_multipath_uses_dev(const struct fib6_info *rt, + const struct net_device *dev) +{ + struct fib6_info *iter; + + if (rt->fib6_nh->fib_nh_dev == dev) + return true; + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) + if (iter->fib6_nh->fib_nh_dev == dev) + return true; + + return false; +} + +static void rt6_multipath_flush(struct fib6_info *rt) +{ + struct fib6_info *iter; + + rt->should_flush = 1; + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) + iter->should_flush = 1; +} + +static unsigned int rt6_multipath_dead_count(const struct fib6_info *rt, + const struct net_device *down_dev) +{ + struct fib6_info *iter; + unsigned int dead = 0; + + if (rt->fib6_nh->fib_nh_dev == down_dev || + rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD) + dead++; + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) + if (iter->fib6_nh->fib_nh_dev == down_dev || + iter->fib6_nh->fib_nh_flags & RTNH_F_DEAD) + dead++; + + return dead; +} + +static void rt6_multipath_nh_flags_set(struct fib6_info *rt, + const struct net_device *dev, + unsigned char nh_flags) +{ + struct fib6_info *iter; + + if (rt->fib6_nh->fib_nh_dev == dev) + rt->fib6_nh->fib_nh_flags |= nh_flags; + list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) + if (iter->fib6_nh->fib_nh_dev == dev) + iter->fib6_nh->fib_nh_flags |= nh_flags; +} + +/* called with write lock held for table with rt */ +static int fib6_ifdown(struct fib6_info *rt, void *p_arg) +{ + const struct arg_netdev_event *arg = p_arg; + const struct net_device *dev = arg->dev; + struct net *net = dev_net(dev); + + if (rt == net->ipv6.fib6_null_entry || rt->nh) + return 0; + + switch (arg->event) { + case NETDEV_UNREGISTER: + return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0; + case NETDEV_DOWN: + if (rt->should_flush) + return -1; + if (!rt->fib6_nsiblings) + return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0; + if (rt6_multipath_uses_dev(rt, dev)) { + unsigned int count; + + count = rt6_multipath_dead_count(rt, dev); + if (rt->fib6_nsiblings + 1 == count) { + rt6_multipath_flush(rt); + return -1; + } + rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD | + RTNH_F_LINKDOWN); + fib6_update_sernum(net, rt); + rt6_multipath_rebalance(rt); + } + return -2; + case NETDEV_CHANGE: + if (rt->fib6_nh->fib_nh_dev != dev || + rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST)) + break; + rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN; + rt6_multipath_rebalance(rt); + break; + } + + return 0; +} + +void rt6_sync_down_dev(struct net_device *dev, unsigned long event) +{ + struct arg_netdev_event arg = { + .dev = dev, + { + .event = event, + }, + }; + struct net *net = dev_net(dev); + + if (net->ipv6.sysctl.skip_notify_on_dev_down) + fib6_clean_all_skip_notify(net, fib6_ifdown, &arg); + else + fib6_clean_all(net, fib6_ifdown, &arg); +} + +void rt6_disable_ip(struct net_device *dev, unsigned long event) +{ + rt6_sync_down_dev(dev, event); + rt6_uncached_list_flush_dev(dev); + neigh_ifdown(&nd_tbl, dev); } struct rt6_mtu_change_arg { struct net_device *dev; unsigned int mtu; + struct fib6_info *f6i; }; -static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) +static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg) +{ + struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *)_arg; + struct fib6_info *f6i = arg->f6i; + + /* For administrative MTU increase, there is no way to discover + * IPv6 PMTU increase, so PMTU increase should be updated here. + * Since RFC 1981 doesn't include administrative MTU increase + * update PMTU increase is a MUST. (i.e. jumbo frame) + */ + if (nh->fib_nh_dev == arg->dev) { + struct inet6_dev *idev = __in6_dev_get(arg->dev); + u32 mtu = f6i->fib6_pmtu; + + if (mtu >= arg->mtu || + (mtu < arg->mtu && mtu == idev->cnf.mtu6)) + fib6_metric_set(f6i, RTAX_MTU, arg->mtu); + + spin_lock_bh(&rt6_exception_lock); + rt6_exceptions_update_pmtu(idev, nh, arg->mtu); + spin_unlock_bh(&rt6_exception_lock); + } + + return 0; +} + +static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg) { struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg; struct inet6_dev *idev; @@ -2198,28 +5057,17 @@ static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) if (!idev) return 0; - /* For administrative MTU increase, there is no way to discover - IPv6 PMTU increase, so PMTU increase should be updated here. - Since RFC 1981 doesn't include administrative MTU increase - update PMTU increase is a MUST. (i.e. jumbo frame) - */ - /* - If new MTU is less than route PMTU, this new MTU will be the - lowest MTU in the path, update the route PMTU to reflect PMTU - decreases; if new MTU is greater than route PMTU, and the - old MTU is the lowest MTU in the path, update the route PMTU - to reflect the increase. In this case if the other nodes' MTU - also have the lowest MTU, TOO BIG MESSAGE will be lead to - PMTU discouvery. - */ - if (rt->dst.dev == arg->dev && - !dst_metric_locked(&rt->dst, RTAX_MTU) && - (dst_mtu(&rt->dst) >= arg->mtu || - (dst_mtu(&rt->dst) < arg->mtu && - dst_mtu(&rt->dst) == idev->cnf.mtu6))) { - dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu); + if (fib6_metric_locked(f6i, RTAX_MTU)) + return 0; + + arg->f6i = f6i; + if (f6i->nh) { + /* fib6_nh_mtu_change only returns 0, so this is safe */ + return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change, + arg); } - return 0; + + return fib6_nh_mtu_change(f6i->fib6_nh, arg); } void rt6_mtu_change(struct net_device *dev, unsigned int mtu) @@ -2229,39 +5077,121 @@ void rt6_mtu_change(struct net_device *dev, unsigned int mtu) .mtu = mtu, }; - fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg); + fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg); } static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { + [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 }, [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) }, + [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) }, [RTA_OIF] = { .type = NLA_U32 }, [RTA_IIF] = { .type = NLA_U32 }, [RTA_PRIORITY] = { .type = NLA_U32 }, [RTA_METRICS] = { .type = NLA_NESTED }, [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, + [RTA_PREF] = { .type = NLA_U8 }, + [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, + [RTA_ENCAP] = { .type = NLA_NESTED }, + [RTA_EXPIRES] = { .type = NLA_U32 }, + [RTA_UID] = { .type = NLA_U32 }, + [RTA_MARK] = { .type = NLA_U32 }, + [RTA_TABLE] = { .type = NLA_U32 }, + [RTA_IP_PROTO] = { .type = NLA_U8 }, + [RTA_SPORT] = { .type = NLA_U16 }, + [RTA_DPORT] = { .type = NLA_U16 }, + [RTA_NH_ID] = { .type = NLA_U32 }, + [RTA_FLOWLABEL] = { .type = NLA_BE32 }, }; +static int rtm_to_fib6_multipath_config(struct fib6_config *cfg, + struct netlink_ext_ack *extack, + bool newroute) +{ + struct rtnexthop *rtnh; + int remaining; + + remaining = cfg->fc_mp_len; + rtnh = (struct rtnexthop *)cfg->fc_mp; + + if (!rtnh_ok(rtnh, remaining)) { + NL_SET_ERR_MSG(extack, "Invalid nexthop configuration - no valid nexthops"); + return -EINVAL; + } + + do { + bool has_gateway = cfg->fc_flags & RTF_GATEWAY; + int attrlen = rtnh_attrlen(rtnh); + + if (attrlen > 0) { + struct nlattr *nla, *attrs; + + attrs = rtnh_attrs(rtnh); + nla = nla_find(attrs, attrlen, RTA_GATEWAY); + if (nla) { + if (nla_len(nla) < sizeof(cfg->fc_gateway)) { + NL_SET_ERR_MSG(extack, + "Invalid IPv6 address in RTA_GATEWAY"); + return -EINVAL; + } + + has_gateway = true; + } + } + + if (newroute && (cfg->fc_nh_id || !has_gateway)) { + NL_SET_ERR_MSG(extack, + "Device only routes can not be added for IPv6 using the multipath API."); + return -EINVAL; + } + + rtnh = rtnh_next(rtnh, &remaining); + } while (rtnh_ok(rtnh, remaining)); + + return lwtunnel_valid_encap_type_attr(cfg->fc_mp, cfg->fc_mp_len, extack); +} + static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, - struct fib6_config *cfg) + struct fib6_config *cfg, + struct netlink_ext_ack *extack) { - struct rtmsg *rtm; + bool newroute = nlh->nlmsg_type == RTM_NEWROUTE; struct nlattr *tb[RTA_MAX+1]; + struct rtmsg *rtm; + unsigned int pref; int err; - err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); + err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, + rtm_ipv6_policy, extack); if (err < 0) goto errout; err = -EINVAL; rtm = nlmsg_data(nlh); - memset(cfg, 0, sizeof(*cfg)); - cfg->fc_table = rtm->rtm_table; - cfg->fc_dst_len = rtm->rtm_dst_len; - cfg->fc_src_len = rtm->rtm_src_len; - cfg->fc_flags = RTF_UP; - cfg->fc_protocol = rtm->rtm_protocol; - cfg->fc_type = rtm->rtm_type; + if (rtm->rtm_tos) { + NL_SET_ERR_MSG(extack, + "Invalid dsfield (tos): option not available for IPv6"); + goto errout; + } + + if (tb[RTA_FLOWLABEL]) { + NL_SET_ERR_MSG_ATTR(extack, tb[RTA_FLOWLABEL], + "Flow label cannot be specified for this operation"); + goto errout; + } + + *cfg = (struct fib6_config){ + .fc_table = rtm->rtm_table, + .fc_dst_len = rtm->rtm_dst_len, + .fc_src_len = rtm->rtm_src_len, + .fc_flags = RTF_UP, + .fc_protocol = rtm->rtm_protocol, + .fc_type = rtm->rtm_type, + + .fc_nlinfo.portid = NETLINK_CB(skb).portid, + .fc_nlinfo.nlh = nlh, + .fc_nlinfo.nl_net = sock_net(skb->sk), + }; if (rtm->rtm_type == RTN_UNREACHABLE || rtm->rtm_type == RTN_BLACKHOLE || @@ -2272,14 +5202,29 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, if (rtm->rtm_type == RTN_LOCAL) cfg->fc_flags |= RTF_LOCAL; - cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; - cfg->fc_nlinfo.nlh = nlh; - cfg->fc_nlinfo.nl_net = sock_net(skb->sk); + if (rtm->rtm_flags & RTM_F_CLONED) + cfg->fc_flags |= RTF_CACHE; + + cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK); + + if (tb[RTA_NH_ID]) { + if (tb[RTA_GATEWAY] || tb[RTA_OIF] || + tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) { + NL_SET_ERR_MSG(extack, + "Nexthop specification and nexthop id are mutually exclusive"); + goto errout; + } + cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]); + } if (tb[RTA_GATEWAY]) { - nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16); + cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]); cfg->fc_flags |= RTF_GATEWAY; } + if (tb[RTA_VIA]) { + NL_SET_ERR_MSG(extack, "IPv6 does not support RTA_VIA attribute"); + goto errout; + } if (tb[RTA_DST]) { int plen = (rtm->rtm_dst_len + 7) >> 3; @@ -2300,7 +5245,7 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, } if (tb[RTA_PREFSRC]) - nla_memcpy(&cfg->fc_prefsrc, tb[RTA_PREFSRC], 16); + cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]); if (tb[RTA_OIF]) cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]); @@ -2319,6 +5264,38 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, if (tb[RTA_MULTIPATH]) { cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]); cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]); + + err = rtm_to_fib6_multipath_config(cfg, extack, newroute); + if (err < 0) + goto errout; + } + + if (tb[RTA_PREF]) { + pref = nla_get_u8(tb[RTA_PREF]); + if (pref != ICMPV6_ROUTER_PREF_LOW && + pref != ICMPV6_ROUTER_PREF_HIGH) + pref = ICMPV6_ROUTER_PREF_MEDIUM; + cfg->fc_flags |= RTF_PREF(pref); + } + + if (tb[RTA_ENCAP]) + cfg->fc_encap = tb[RTA_ENCAP]; + + if (tb[RTA_ENCAP_TYPE]) { + cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]); + + err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack); + if (err < 0) + goto errout; + } + + if (tb[RTA_EXPIRES]) { + unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ); + + if (addrconf_finite_timeout(timeout)) { + cfg->fc_expires = jiffies_to_clock_t(timeout * HZ); + cfg->fc_flags |= RTF_EXPIRES; + } } err = 0; @@ -2326,19 +5303,122 @@ errout: return err; } -static int ip6_route_multipath(struct fib6_config *cfg, int add) +struct rt6_nh { + struct fib6_info *fib6_info; + struct fib6_config r_cfg; + struct list_head list; +}; + +static int ip6_route_info_append(struct list_head *rt6_nh_list, + struct fib6_info *rt, + struct fib6_config *r_cfg) +{ + struct rt6_nh *nh; + + list_for_each_entry(nh, rt6_nh_list, list) { + /* check if fib6_info already exists */ + if (rt6_duplicate_nexthop(nh->fib6_info, rt)) + return -EEXIST; + } + + nh = kzalloc(sizeof(*nh), GFP_KERNEL); + if (!nh) + return -ENOMEM; + + nh->fib6_info = rt; + memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg)); + list_add_tail(&nh->list, rt6_nh_list); + + return 0; +} + +static void ip6_route_mpath_notify(struct fib6_info *rt, + struct fib6_info *rt_last, + struct nl_info *info, + __u16 nlflags) { + /* if this is an APPEND route, then rt points to the first route + * inserted and rt_last points to last route inserted. Userspace + * wants a consistent dump of the route which starts at the first + * nexthop. Since sibling routes are always added at the end of + * the list, find the first sibling of the last route appended + */ + rcu_read_lock(); + + if ((nlflags & NLM_F_APPEND) && rt_last && + READ_ONCE(rt_last->fib6_nsiblings)) { + rt = list_first_or_null_rcu(&rt_last->fib6_siblings, + struct fib6_info, + fib6_siblings); + } + + if (rt) + inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags); + + rcu_read_unlock(); +} + +static bool ip6_route_mpath_should_notify(const struct fib6_info *rt) +{ + bool rt_can_ecmp = rt6_qualify_for_ecmp(rt); + bool should_notify = false; + struct fib6_info *leaf; + struct fib6_node *fn; + + rcu_read_lock(); + fn = rcu_dereference(rt->fib6_node); + if (!fn) + goto out; + + leaf = rcu_dereference(fn->leaf); + if (!leaf) + goto out; + + if (rt == leaf || + (rt_can_ecmp && rt->fib6_metric == leaf->fib6_metric && + rt6_qualify_for_ecmp(leaf))) + should_notify = true; +out: + rcu_read_unlock(); + + return should_notify; +} + +static int ip6_route_multipath_add(struct fib6_config *cfg, + struct netlink_ext_ack *extack) +{ + struct fib6_info *rt_notif = NULL, *rt_last = NULL; + struct nl_info *info = &cfg->fc_nlinfo; + struct rt6_nh *nh, *nh_safe; struct fib6_config r_cfg; struct rtnexthop *rtnh; + LIST_HEAD(rt6_nh_list); + struct rt6_nh *err_nh; + struct fib6_info *rt; + __u16 nlflags; int remaining; int attrlen; - int err = 0, last_err = 0; + int replace; + int nhn = 0; + int err; + + err = fib6_config_validate(cfg, extack); + if (err) + return err; + + replace = (cfg->fc_nlinfo.nlh && + (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE)); + + nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE; + if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND) + nlflags |= NLM_F_APPEND; -beginning: - rtnh = (struct rtnexthop *)cfg->fc_mp; remaining = cfg->fc_mp_len; + rtnh = (struct rtnexthop *)cfg->fc_mp; - /* Parse a Multipath Entry */ + /* Parse a Multipath Entry and build a list (rt6_nh_list) of + * fib6_info structs per nexthop + */ while (rtnh_ok(rtnh, remaining)) { memcpy(&r_cfg, cfg, sizeof(*cfg)); if (rtnh->rtnh_ifindex) @@ -2350,69 +5430,274 @@ beginning: nla = nla_find(attrs, attrlen, RTA_GATEWAY); if (nla) { - nla_memcpy(&r_cfg.fc_gateway, nla, 16); + r_cfg.fc_gateway = nla_get_in6_addr(nla); r_cfg.fc_flags |= RTF_GATEWAY; } + + r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP); + nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE); + if (nla) + r_cfg.fc_encap_type = nla_get_u16(nla); } - err = add ? ip6_route_add(&r_cfg) : ip6_route_del(&r_cfg); + + r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK); + rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack); + if (IS_ERR(rt)) { + err = PTR_ERR(rt); + rt = NULL; + goto cleanup; + } + + err = ip6_route_info_create_nh(rt, &r_cfg, GFP_KERNEL, extack); if (err) { - last_err = err; - /* If we are trying to remove a route, do not stop the - * loop when ip6_route_del() fails (because next hop is - * already gone), we should try to remove all next hops. - */ - if (add) { - /* If add fails, we should try to delete all - * next hops that have been already added. - */ - add = 0; - goto beginning; - } + rt = NULL; + goto cleanup; + } + + rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1; + + err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg); + if (err) { + fib6_info_release(rt); + goto cleanup; + } + + rtnh = rtnh_next(rtnh, &remaining); + } + + /* for add and replace send one notification with all nexthops. + * Skip the notification in fib6_add_rt2node and send one with + * the full route when done + */ + info->skip_notify = 1; + + /* For add and replace, send one notification with all nexthops. For + * append, send one notification with all appended nexthops. + */ + info->skip_notify_kernel = 1; + + err_nh = NULL; + list_for_each_entry(nh, &rt6_nh_list, list) { + err = __ip6_ins_rt(nh->fib6_info, info, extack); + + if (err) { + if (replace && nhn) + NL_SET_ERR_MSG_MOD(extack, + "multipath route replace failed (check consistency of installed routes)"); + err_nh = nh; + goto add_errout; } + /* save reference to last route successfully inserted */ + rt_last = nh->fib6_info; + + /* save reference to first route for notification */ + if (!rt_notif) + rt_notif = nh->fib6_info; + /* Because each route is added like a single route we remove - * this flag after the first nexthop (if there is a collision, - * we have already fail to add the first nexthop: - * fib6_add_rt2node() has reject it). + * these flags after the first nexthop: if there is a collision, + * we have already failed to add the first nexthop: + * fib6_add_rt2node() has rejected it; when replacing, old + * nexthops have been replaced by first new, the rest should + * be added to it. */ - cfg->fc_nlinfo.nlh->nlmsg_flags &= ~NLM_F_EXCL; + if (cfg->fc_nlinfo.nlh) { + cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL | + NLM_F_REPLACE); + cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE; + } + nhn++; + } + + /* An in-kernel notification should only be sent in case the new + * multipath route is added as the first route in the node, or if + * it was appended to it. We pass 'rt_notif' since it is the first + * sibling and might allow us to skip some checks in the replace case. + */ + if (ip6_route_mpath_should_notify(rt_notif)) { + enum fib_event_type fib_event; + + if (rt_notif->fib6_nsiblings != nhn - 1) + fib_event = FIB_EVENT_ENTRY_APPEND; + else + fib_event = FIB_EVENT_ENTRY_REPLACE; + + err = call_fib6_multipath_entry_notifiers(info->nl_net, + fib_event, rt_notif, + nhn - 1, extack); + if (err) { + /* Delete all the siblings that were just added */ + err_nh = NULL; + goto add_errout; + } + } + + /* success ... tell user about new route */ + ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags); + goto cleanup; + +add_errout: + /* send notification for routes that were added so that + * the delete notifications sent by ip6_route_del are + * coherent + */ + if (rt_notif) + ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags); + + /* Delete routes that were already added */ + list_for_each_entry(nh, &rt6_nh_list, list) { + if (err_nh == nh) + break; + ip6_route_del(&nh->r_cfg, extack); + } + +cleanup: + list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, list) { + fib6_info_release(nh->fib6_info); + list_del(&nh->list); + kfree(nh); + } + + return err; +} + +static int ip6_route_multipath_del(struct fib6_config *cfg, + struct netlink_ext_ack *extack) +{ + struct fib6_config r_cfg; + struct rtnexthop *rtnh; + int last_err = 0; + int remaining; + int attrlen; + int err; + + remaining = cfg->fc_mp_len; + rtnh = (struct rtnexthop *)cfg->fc_mp; + + /* Parse a Multipath Entry */ + while (rtnh_ok(rtnh, remaining)) { + memcpy(&r_cfg, cfg, sizeof(*cfg)); + if (rtnh->rtnh_ifindex) + r_cfg.fc_ifindex = rtnh->rtnh_ifindex; + + attrlen = rtnh_attrlen(rtnh); + if (attrlen > 0) { + struct nlattr *nla, *attrs = rtnh_attrs(rtnh); + + nla = nla_find(attrs, attrlen, RTA_GATEWAY); + if (nla) { + r_cfg.fc_gateway = nla_get_in6_addr(nla); + r_cfg.fc_flags |= RTF_GATEWAY; + } + } + + err = ip6_route_del(&r_cfg, extack); + if (err) + last_err = err; + rtnh = rtnh_next(rtnh, &remaining); } return last_err; } -static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh) +static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) { struct fib6_config cfg; int err; - err = rtm_to_fib6_config(skb, nlh, &cfg); + err = rtm_to_fib6_config(skb, nlh, &cfg, extack); if (err < 0) return err; - if (cfg.fc_mp) - return ip6_route_multipath(&cfg, 0); - else - return ip6_route_del(&cfg); + if (cfg.fc_nh_id) { + rcu_read_lock(); + err = !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id); + rcu_read_unlock(); + + if (err) { + NL_SET_ERR_MSG(extack, "Nexthop id does not exist"); + return -EINVAL; + } + } + + if (cfg.fc_mp) { + return ip6_route_multipath_del(&cfg, extack); + } else { + cfg.fc_delete_all_nh = 1; + return ip6_route_del(&cfg, extack); + } } -static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh) +static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) { struct fib6_config cfg; int err; - err = rtm_to_fib6_config(skb, nlh, &cfg); + err = rtm_to_fib6_config(skb, nlh, &cfg, extack); if (err < 0) return err; + if (cfg.fc_metric == 0) + cfg.fc_metric = IP6_RT_PRIO_USER; + if (cfg.fc_mp) - return ip6_route_multipath(&cfg, 1); + return ip6_route_multipath_add(&cfg, extack); else - return ip6_route_add(&cfg); + return ip6_route_add(&cfg, GFP_KERNEL, extack); +} + +/* add the overhead of this fib6_nh to nexthop_len */ +static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg) +{ + int *nexthop_len = arg; + + *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */ + + NLA_ALIGN(sizeof(struct rtnexthop)) + + nla_total_size(16); /* RTA_GATEWAY */ + + if (nh->fib_nh_lws) { + /* RTA_ENCAP_TYPE */ + *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws); + /* RTA_ENCAP */ + *nexthop_len += nla_total_size(2); + } + + return 0; } -static inline size_t rt6_nlmsg_size(void) +static size_t rt6_nlmsg_size(struct fib6_info *f6i) { + struct fib6_info *sibling; + struct fib6_nh *nh; + int nexthop_len; + + if (f6i->nh) { + nexthop_len = nla_total_size(4); /* RTA_NH_ID */ + nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size, + &nexthop_len); + goto common; + } + + rcu_read_lock(); +retry: + nh = f6i->fib6_nh; + nexthop_len = 0; + if (READ_ONCE(f6i->fib6_nsiblings)) { + rt6_nh_nlmsg_size(nh, &nexthop_len); + + list_for_each_entry_rcu(sibling, &f6i->fib6_siblings, + fib6_siblings) { + rt6_nh_nlmsg_size(sibling->fib6_nh, &nexthop_len); + if (!READ_ONCE(f6i->fib6_nsiblings)) + goto retry; + } + } + rcu_read_unlock(); + nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws); +common: return NLMSG_ALIGN(sizeof(struct rtmsg)) + nla_total_size(16) /* RTA_SRC */ + nla_total_size(16) /* RTA_DST */ @@ -2423,187 +5708,500 @@ static inline size_t rt6_nlmsg_size(void) + nla_total_size(4) /* RTA_OIF */ + nla_total_size(4) /* RTA_PRIORITY */ + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */ - + nla_total_size(sizeof(struct rta_cacheinfo)); + + nla_total_size(sizeof(struct rta_cacheinfo)) + + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */ + + nla_total_size(1) /* RTA_PREF */ + + nexthop_len; } -static int rt6_fill_node(struct net *net, - struct sk_buff *skb, struct rt6_info *rt, - struct in6_addr *dst, struct in6_addr *src, - int iif, int type, u32 portid, u32 seq, - int prefix, int nowait, unsigned int flags) +static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh, + unsigned char *flags) { - struct rtmsg *rtm; - struct nlmsghdr *nlh; - long expires; - u32 table; + if (nexthop_is_multipath(nh)) { + struct nlattr *mp; - if (prefix) { /* user wants prefix routes only */ - if (!(rt->rt6i_flags & RTF_PREFIX_RT)) { - /* success since this is not a prefix route */ - return 1; - } + mp = nla_nest_start_noflag(skb, RTA_MULTIPATH); + if (!mp) + goto nla_put_failure; + + if (nexthop_mpath_fill_node(skb, nh, AF_INET6)) + goto nla_put_failure; + + nla_nest_end(skb, mp); + } else { + struct fib6_nh *fib6_nh; + + fib6_nh = nexthop_fib6_nh(nh); + if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6, + flags, false) < 0) + goto nla_put_failure; } + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static int rt6_fill_node(struct net *net, struct sk_buff *skb, + struct fib6_info *rt, struct dst_entry *dst, + struct in6_addr *dest, struct in6_addr *src, + int iif, int type, u32 portid, u32 seq, + unsigned int flags) +{ + struct rt6_info *rt6 = dst_rt6_info(dst); + struct rt6key *rt6_dst, *rt6_src; + u32 *pmetrics, table, rt6_flags; + unsigned char nh_flags = 0; + struct nlmsghdr *nlh; + struct rtmsg *rtm; + long expires = 0; + nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags); if (!nlh) return -EMSGSIZE; + if (rt6) { + rt6_dst = &rt6->rt6i_dst; + rt6_src = &rt6->rt6i_src; + rt6_flags = rt6->rt6i_flags; + } else { + rt6_dst = &rt->fib6_dst; + rt6_src = &rt->fib6_src; + rt6_flags = rt->fib6_flags; + } + rtm = nlmsg_data(nlh); rtm->rtm_family = AF_INET6; - rtm->rtm_dst_len = rt->rt6i_dst.plen; - rtm->rtm_src_len = rt->rt6i_src.plen; + rtm->rtm_dst_len = rt6_dst->plen; + rtm->rtm_src_len = rt6_src->plen; rtm->rtm_tos = 0; - if (rt->rt6i_table) - table = rt->rt6i_table->tb6_id; + if (rt->fib6_table) + table = rt->fib6_table->tb6_id; else table = RT6_TABLE_UNSPEC; - rtm->rtm_table = table; + rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT; if (nla_put_u32(skb, RTA_TABLE, table)) goto nla_put_failure; - if (rt->rt6i_flags & RTF_REJECT) { - switch (rt->dst.error) { - case -EINVAL: - rtm->rtm_type = RTN_BLACKHOLE; - break; - case -EACCES: - rtm->rtm_type = RTN_PROHIBIT; - break; - case -EAGAIN: - rtm->rtm_type = RTN_THROW; - break; - default: - rtm->rtm_type = RTN_UNREACHABLE; - break; - } - } - else if (rt->rt6i_flags & RTF_LOCAL) - rtm->rtm_type = RTN_LOCAL; - else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK)) - rtm->rtm_type = RTN_LOCAL; - else - rtm->rtm_type = RTN_UNICAST; + + rtm->rtm_type = rt->fib6_type; rtm->rtm_flags = 0; rtm->rtm_scope = RT_SCOPE_UNIVERSE; - rtm->rtm_protocol = rt->rt6i_protocol; - if (rt->rt6i_flags & RTF_DYNAMIC) - rtm->rtm_protocol = RTPROT_REDIRECT; - else if (rt->rt6i_flags & RTF_ADDRCONF) { - if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO)) - rtm->rtm_protocol = RTPROT_RA; - else - rtm->rtm_protocol = RTPROT_KERNEL; - } + rtm->rtm_protocol = rt->fib6_protocol; - if (rt->rt6i_flags & RTF_CACHE) + if (rt6_flags & RTF_CACHE) rtm->rtm_flags |= RTM_F_CLONED; - if (dst) { - if (nla_put(skb, RTA_DST, 16, dst)) + if (dest) { + if (nla_put_in6_addr(skb, RTA_DST, dest)) goto nla_put_failure; rtm->rtm_dst_len = 128; } else if (rtm->rtm_dst_len) - if (nla_put(skb, RTA_DST, 16, &rt->rt6i_dst.addr)) + if (nla_put_in6_addr(skb, RTA_DST, &rt6_dst->addr)) goto nla_put_failure; #ifdef CONFIG_IPV6_SUBTREES if (src) { - if (nla_put(skb, RTA_SRC, 16, src)) + if (nla_put_in6_addr(skb, RTA_SRC, src)) goto nla_put_failure; rtm->rtm_src_len = 128; } else if (rtm->rtm_src_len && - nla_put(skb, RTA_SRC, 16, &rt->rt6i_src.addr)) + nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr)) goto nla_put_failure; #endif if (iif) { #ifdef CONFIG_IPV6_MROUTE - if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) { - int err = ip6mr_get_route(net, skb, rtm, nowait); - if (err <= 0) { - if (!nowait) { - if (err == 0) - return 0; - goto nla_put_failure; - } else { - if (err == -EMSGSIZE) - goto nla_put_failure; - } - } + if (ipv6_addr_is_multicast(&rt6_dst->addr)) { + int err = ip6mr_get_route(net, skb, rtm, portid); + + if (err == 0) + return 0; + if (err < 0) + goto nla_put_failure; } else #endif if (nla_put_u32(skb, RTA_IIF, iif)) goto nla_put_failure; - } else if (dst) { + } else if (dest) { struct in6_addr saddr_buf; - if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 && - nla_put(skb, RTA_PREFSRC, 16, &saddr_buf)) + if (ip6_route_get_saddr(net, rt, dest, 0, 0, &saddr_buf) == 0 && + nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf)) goto nla_put_failure; } - if (rt->rt6i_prefsrc.plen) { + if (rt->fib6_prefsrc.plen) { struct in6_addr saddr_buf; - saddr_buf = rt->rt6i_prefsrc.addr; - if (nla_put(skb, RTA_PREFSRC, 16, &saddr_buf)) + saddr_buf = rt->fib6_prefsrc.addr; + if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf)) goto nla_put_failure; } - if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0) + pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics; + if (rtnetlink_put_metrics(skb, pmetrics) < 0) goto nla_put_failure; - if (rt->rt6i_flags & RTF_GATEWAY) { - if (nla_put(skb, RTA_GATEWAY, 16, &rt->rt6i_gateway) < 0) + if (nla_put_u32(skb, RTA_PRIORITY, rt->fib6_metric)) + goto nla_put_failure; + + /* For multipath routes, walk the siblings list and add + * each as a nexthop within RTA_MULTIPATH. + */ + if (rt6) { + struct net_device *dev; + + if (rt6_flags & RTF_GATEWAY && + nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway)) + goto nla_put_failure; + + dev = dst_dev(dst); + if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) + goto nla_put_failure; + + if (lwtunnel_fill_encap(skb, dst->lwtstate, RTA_ENCAP, RTA_ENCAP_TYPE) < 0) goto nla_put_failure; + } else if (READ_ONCE(rt->fib6_nsiblings)) { + struct fib6_info *sibling; + struct nlattr *mp; + + mp = nla_nest_start_noflag(skb, RTA_MULTIPATH); + if (!mp) + goto nla_put_failure; + + if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common, + rt->fib6_nh->fib_nh_weight, AF_INET6, + 0) < 0) + goto nla_put_failure; + + rcu_read_lock(); + + list_for_each_entry_rcu(sibling, &rt->fib6_siblings, + fib6_siblings) { + if (fib_add_nexthop(skb, &sibling->fib6_nh->nh_common, + sibling->fib6_nh->fib_nh_weight, + AF_INET6, 0) < 0) { + rcu_read_unlock(); + + goto nla_put_failure; + } + } + + rcu_read_unlock(); + + nla_nest_end(skb, mp); + } else if (rt->nh) { + if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id)) + goto nla_put_failure; + + if (nexthop_is_blackhole(rt->nh)) + rtm->rtm_type = RTN_BLACKHOLE; + + if (READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode) && + rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0) + goto nla_put_failure; + + rtm->rtm_flags |= nh_flags; + } else { + if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6, + &nh_flags, false) < 0) + goto nla_put_failure; + + rtm->rtm_flags |= nh_flags; } - if (rt->dst.dev && - nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) - goto nla_put_failure; - if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric)) - goto nla_put_failure; + if (rt6_flags & RTF_EXPIRES) { + expires = dst ? READ_ONCE(dst->expires) : rt->expires; + expires -= jiffies; + } - expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0; + if (!dst) { + if (READ_ONCE(rt->offload)) + rtm->rtm_flags |= RTM_F_OFFLOAD; + if (READ_ONCE(rt->trap)) + rtm->rtm_flags |= RTM_F_TRAP; + if (READ_ONCE(rt->offload_failed)) + rtm->rtm_flags |= RTM_F_OFFLOAD_FAILED; + } + + if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0) + goto nla_put_failure; - if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0) + if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags))) goto nla_put_failure; - return nlmsg_end(skb, nlh); + + nlmsg_end(skb, nlh); + return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } -int rt6_dump_route(struct rt6_info *rt, void *p_arg) +static int fib6_info_nh_uses_dev(struct fib6_nh *nh, void *arg) +{ + const struct net_device *dev = arg; + + if (nh->fib_nh_dev == dev) + return 1; + + return 0; +} + +static bool fib6_info_uses_dev(const struct fib6_info *f6i, + const struct net_device *dev) +{ + if (f6i->nh) { + struct net_device *_dev = (struct net_device *)dev; + + return !!nexthop_for_each_fib6_nh(f6i->nh, + fib6_info_nh_uses_dev, + _dev); + } + + if (f6i->fib6_nh->fib_nh_dev == dev) + return true; + + if (READ_ONCE(f6i->fib6_nsiblings)) { + const struct fib6_info *sibling; + + rcu_read_lock(); + list_for_each_entry_rcu(sibling, &f6i->fib6_siblings, + fib6_siblings) { + if (sibling->fib6_nh->fib_nh_dev == dev) { + rcu_read_unlock(); + return true; + } + if (!READ_ONCE(f6i->fib6_nsiblings)) + break; + } + rcu_read_unlock(); + } + return false; +} + +struct fib6_nh_exception_dump_walker { + struct rt6_rtnl_dump_arg *dump; + struct fib6_info *rt; + unsigned int flags; + unsigned int skip; + unsigned int count; +}; + +static int rt6_nh_dump_exceptions(struct fib6_nh *nh, void *arg) +{ + struct fib6_nh_exception_dump_walker *w = arg; + struct rt6_rtnl_dump_arg *dump = w->dump; + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + int i, err; + + bucket = fib6_nh_get_excptn_bucket(nh, NULL); + if (!bucket) + return 0; + + for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) { + hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) { + if (w->skip) { + w->skip--; + continue; + } + + /* Expiration of entries doesn't bump sernum, insertion + * does. Removal is triggered by insertion, so we can + * rely on the fact that if entries change between two + * partial dumps, this node is scanned again completely, + * see rt6_insert_exception() and fib6_dump_table(). + * + * Count expired entries we go through as handled + * entries that we'll skip next time, in case of partial + * node dump. Otherwise, if entries expire meanwhile, + * we'll skip the wrong amount. + */ + if (rt6_check_expired(rt6_ex->rt6i)) { + w->count++; + continue; + } + + err = rt6_fill_node(dump->net, dump->skb, w->rt, + &rt6_ex->rt6i->dst, NULL, NULL, 0, + RTM_NEWROUTE, + NETLINK_CB(dump->cb->skb).portid, + dump->cb->nlh->nlmsg_seq, w->flags); + if (err) + return err; + + w->count++; + } + bucket++; + } + + return 0; +} + +/* Return -1 if done with node, number of handled routes on partial dump */ +int rt6_dump_route(struct fib6_info *rt, void *p_arg, unsigned int skip) { struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg; - int prefix; + struct fib_dump_filter *filter = &arg->filter; + unsigned int flags = NLM_F_MULTI; + struct net *net = arg->net; + int count = 0; + + if (rt == net->ipv6.fib6_null_entry) + return -1; + + if ((filter->flags & RTM_F_PREFIX) && + !(rt->fib6_flags & RTF_PREFIX_RT)) { + /* success since this is not a prefix route */ + return -1; + } + if (filter->filter_set && + ((filter->rt_type && rt->fib6_type != filter->rt_type) || + (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) || + (filter->protocol && rt->fib6_protocol != filter->protocol))) { + return -1; + } + + if (filter->filter_set || + !filter->dump_routes || !filter->dump_exceptions) { + flags |= NLM_F_DUMP_FILTERED; + } + + if (filter->dump_routes) { + if (skip) { + skip--; + } else { + if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL, + 0, RTM_NEWROUTE, + NETLINK_CB(arg->cb->skb).portid, + arg->cb->nlh->nlmsg_seq, flags)) { + return 0; + } + count++; + } + } + + if (filter->dump_exceptions) { + struct fib6_nh_exception_dump_walker w = { .dump = arg, + .rt = rt, + .flags = flags, + .skip = skip, + .count = 0 }; + int err; - if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) { - struct rtmsg *rtm = nlmsg_data(arg->cb->nlh); - prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0; - } else - prefix = 0; + rcu_read_lock(); + if (rt->nh) { + err = nexthop_for_each_fib6_nh(rt->nh, + rt6_nh_dump_exceptions, + &w); + } else { + err = rt6_nh_dump_exceptions(rt->fib6_nh, &w); + } + rcu_read_unlock(); - return rt6_fill_node(arg->net, - arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, - NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq, - prefix, 0, NLM_F_MULTI); + if (err) + return count + w.count; + } + + return -1; } -static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh) +static int inet6_rtm_valid_getroute_req(struct sk_buff *skb, + const struct nlmsghdr *nlh, + struct nlattr **tb, + struct netlink_ext_ack *extack) +{ + struct rtmsg *rtm; + int i, err; + + rtm = nlmsg_payload(nlh, sizeof(*rtm)); + if (!rtm) { + NL_SET_ERR_MSG_MOD(extack, + "Invalid header for get route request"); + return -EINVAL; + } + + if (!netlink_strict_get_check(skb)) + return nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX, + rtm_ipv6_policy, extack); + + if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) || + (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) || + rtm->rtm_table || rtm->rtm_protocol || rtm->rtm_scope || + rtm->rtm_type) { + NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get route request"); + return -EINVAL; + } + if (rtm->rtm_flags & ~RTM_F_FIB_MATCH) { + NL_SET_ERR_MSG_MOD(extack, + "Invalid flags for get route request"); + return -EINVAL; + } + + err = nlmsg_parse_deprecated_strict(nlh, sizeof(*rtm), tb, RTA_MAX, + rtm_ipv6_policy, extack); + if (err) + return err; + + if ((tb[RTA_SRC] && !rtm->rtm_src_len) || + (tb[RTA_DST] && !rtm->rtm_dst_len)) { + NL_SET_ERR_MSG_MOD(extack, "rtm_src_len and rtm_dst_len must be 128 for IPv6"); + return -EINVAL; + } + + if (tb[RTA_FLOWLABEL] && + (nla_get_be32(tb[RTA_FLOWLABEL]) & ~IPV6_FLOWLABEL_MASK)) { + NL_SET_ERR_MSG_ATTR(extack, tb[RTA_FLOWLABEL], + "Invalid flow label"); + return -EINVAL; + } + + for (i = 0; i <= RTA_MAX; i++) { + if (!tb[i]) + continue; + + switch (i) { + case RTA_SRC: + case RTA_DST: + case RTA_IIF: + case RTA_OIF: + case RTA_MARK: + case RTA_UID: + case RTA_SPORT: + case RTA_DPORT: + case RTA_IP_PROTO: + case RTA_FLOWLABEL: + break; + default: + NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request"); + return -EINVAL; + } + } + + return 0; +} + +static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct nlattr *tb[RTA_MAX+1]; + int err, iif = 0, oif = 0; + struct fib6_info *from; + struct dst_entry *dst; struct rt6_info *rt; struct sk_buff *skb; struct rtmsg *rtm; - struct flowi6 fl6; - int err, iif = 0, oif = 0; + struct flowi6 fl6 = {}; + __be32 flowlabel; + bool fibmatch; - err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); + err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack); if (err < 0) goto errout; err = -EINVAL; - memset(&fl6, 0, sizeof(fl6)); + rtm = nlmsg_data(nlh); + fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH); if (tb[RTA_SRC]) { if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr)) @@ -2625,12 +6223,41 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh) if (tb[RTA_OIF]) oif = nla_get_u32(tb[RTA_OIF]); + if (tb[RTA_MARK]) + fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]); + + if (tb[RTA_UID]) + fl6.flowi6_uid = make_kuid(current_user_ns(), + nla_get_u32(tb[RTA_UID])); + else + fl6.flowi6_uid = iif ? INVALID_UID : current_uid(); + + if (tb[RTA_SPORT]) + fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]); + + if (tb[RTA_DPORT]) + fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]); + + if (tb[RTA_IP_PROTO]) { + err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO], + &fl6.flowi6_proto, AF_INET6, + extack); + if (err) + goto errout; + } + + flowlabel = nla_get_be32_default(tb[RTA_FLOWLABEL], 0); + fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, flowlabel); + if (iif) { struct net_device *dev; int flags = 0; - dev = __dev_get_by_index(net, iif); + rcu_read_lock(); + + dev = dev_get_by_index_rcu(net, iif); if (!dev) { + rcu_read_unlock(); err = -ENODEV; goto errout; } @@ -2640,12 +6267,27 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh) if (!ipv6_addr_any(&fl6.saddr)) flags |= RT6_LOOKUP_F_HAS_SADDR; - rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6, - flags); + dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags); + + rcu_read_unlock(); } else { fl6.flowi6_oif = oif; - rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6); + dst = ip6_route_output(net, NULL, &fl6); + } + + + rt = dst_rt6_info(dst); + if (rt->dst.error) { + err = rt->dst.error; + ip6_rt_put(rt); + goto errout; + } + + if (rt == net->ipv6.ip6_null_entry) { + err = rt->dst.error; + ip6_rt_put(rt); + goto errout; } skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); @@ -2655,17 +6297,26 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh) goto errout; } - /* Reserve room for dummy headers, this skb can pass - through good chunk of routing engine. - */ - skb_reset_mac_header(skb); - skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr)); - skb_dst_set(skb, &rt->dst); - err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif, - RTM_NEWROUTE, NETLINK_CB(in_skb).portid, - nlh->nlmsg_seq, 0, 0, 0); + rcu_read_lock(); + from = rcu_dereference(rt->from); + if (from) { + if (fibmatch) + err = rt6_fill_node(net, skb, from, NULL, NULL, NULL, + iif, RTM_NEWROUTE, + NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, 0); + else + err = rt6_fill_node(net, skb, from, dst, &fl6.daddr, + &fl6.saddr, iif, RTM_NEWROUTE, + NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, 0); + } else { + err = -ENETUNREACH; + } + rcu_read_unlock(); + if (err < 0) { kfree_skb(skb); goto errout; @@ -2676,22 +6327,60 @@ errout: return err; } -void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info) +void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info, + unsigned int nlm_flags) { - struct sk_buff *skb; struct net *net = info->nl_net; + struct sk_buff *skb; + size_t sz; u32 seq; int err; err = -ENOBUFS; seq = info->nlh ? info->nlh->nlmsg_seq : 0; - skb = nlmsg_new(rt6_nlmsg_size(), gfp_any()); + rcu_read_lock(); + sz = rt6_nlmsg_size(rt); +retry: + skb = nlmsg_new(sz, GFP_ATOMIC); + if (!skb) + goto errout; + + err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0, + event, info->portid, seq, nlm_flags); + if (err < 0) { + kfree_skb(skb); + /* -EMSGSIZE implies needed space grew under us. */ + if (err == -EMSGSIZE) { + sz = max(rt6_nlmsg_size(rt), sz << 1); + goto retry; + } + goto errout; + } + + rcu_read_unlock(); + + rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE, + info->nlh, GFP_ATOMIC); + return; +errout: + rcu_read_unlock(); + rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); +} + +void fib6_rt_update(struct net *net, struct fib6_info *rt, + struct nl_info *info) +{ + u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; + struct sk_buff *skb; + int err = -ENOBUFS; + + skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any()); if (!skb) goto errout; - err = rt6_fill_node(net, skb, rt, NULL, NULL, 0, - event, info->portid, seq, 0, 0, 0); + err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0, + RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE); if (err < 0) { /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); @@ -2702,9 +6391,61 @@ void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info) info->nlh, gfp_any()); return; errout: - if (err < 0) - rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); + rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); +} + +void fib6_info_hw_flags_set(struct net *net, struct fib6_info *f6i, + bool offload, bool trap, bool offload_failed) +{ + struct sk_buff *skb; + int err; + + if (READ_ONCE(f6i->offload) == offload && + READ_ONCE(f6i->trap) == trap && + READ_ONCE(f6i->offload_failed) == offload_failed) + return; + + WRITE_ONCE(f6i->offload, offload); + WRITE_ONCE(f6i->trap, trap); + + /* 2 means send notifications only if offload_failed was changed. */ + if (net->ipv6.sysctl.fib_notify_on_flag_change == 2 && + READ_ONCE(f6i->offload_failed) == offload_failed) + return; + + WRITE_ONCE(f6i->offload_failed, offload_failed); + + if (!rcu_access_pointer(f6i->fib6_node)) + /* The route was removed from the tree, do not send + * notification. + */ + return; + + if (!net->ipv6.sysctl.fib_notify_on_flag_change) + return; + + skb = nlmsg_new(rt6_nlmsg_size(f6i), GFP_KERNEL); + if (!skb) { + err = -ENOBUFS; + goto errout; + } + + err = rt6_fill_node(net, skb, f6i, NULL, NULL, NULL, 0, RTM_NEWROUTE, 0, + 0, 0); + if (err < 0) { + /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(skb); + goto errout; + } + + rtnl_notify(skb, net, 0, RTNLGRP_IPV6_ROUTE, NULL, GFP_KERNEL); + return; + +errout: + rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); } +EXPORT_SYMBOL(fib6_info_hw_flags_set); static int ip6_route_dev_notify(struct notifier_block *this, unsigned long event, void *ptr) @@ -2712,7 +6453,11 @@ static int ip6_route_dev_notify(struct notifier_block *this, struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct net *net = dev_net(dev); - if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) { + if (!(dev->flags & IFF_LOOPBACK)) + return NOTIFY_OK; + + if (event == NETDEV_REGISTER) { + net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev; net->ipv6.ip6_null_entry->dst.dev = dev; net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev); #ifdef CONFIG_IPV6_MULTIPLE_TABLES @@ -2721,6 +6466,16 @@ static int ip6_route_dev_notify(struct notifier_block *this, net->ipv6.ip6_blk_hole_entry->dst.dev = dev; net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); #endif + } else if (event == NETDEV_UNREGISTER && + dev->reg_state != NETREG_UNREGISTERED) { + /* NETDEV_UNREGISTER could be fired for multiple times by + * netdev_wait_allrefs(). Make sure we only call this once. + */ + in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev); +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev); + in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev); +#endif } return NOTIFY_OK; @@ -2731,66 +6486,13 @@ static int ip6_route_dev_notify(struct notifier_block *this, */ #ifdef CONFIG_PROC_FS - -struct rt6_proc_arg -{ - char *buffer; - int offset; - int length; - int skip; - int len; -}; - -static int rt6_info_route(struct rt6_info *rt, void *p_arg) -{ - struct seq_file *m = p_arg; - - seq_printf(m, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen); - -#ifdef CONFIG_IPV6_SUBTREES - seq_printf(m, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen); -#else - seq_puts(m, "00000000000000000000000000000000 00 "); -#endif - if (rt->rt6i_flags & RTF_GATEWAY) { - seq_printf(m, "%pi6", &rt->rt6i_gateway); - } else { - seq_puts(m, "00000000000000000000000000000000"); - } - seq_printf(m, " %08x %08x %08x %08x %8s\n", - rt->rt6i_metric, atomic_read(&rt->dst.__refcnt), - rt->dst.__use, rt->rt6i_flags, - rt->dst.dev ? rt->dst.dev->name : ""); - return 0; -} - -static int ipv6_route_show(struct seq_file *m, void *v) -{ - struct net *net = (struct net *)m->private; - fib6_clean_all_ro(net, rt6_info_route, 0, m); - return 0; -} - -static int ipv6_route_open(struct inode *inode, struct file *file) -{ - return single_open_net(inode, file, ipv6_route_show); -} - -static const struct file_operations ipv6_route_proc_fops = { - .owner = THIS_MODULE, - .open = ipv6_route_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release_net, -}; - static int rt6_stats_seq_show(struct seq_file *seq, void *v) { struct net *net = (struct net *)seq->private; seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n", net->ipv6.rt6_stats->fib_nodes, net->ipv6.rt6_stats->fib_route_nodes, - net->ipv6.rt6_stats->fib_rt_alloc, + atomic_read(&net->ipv6.rt6_stats->fib_rt_alloc), net->ipv6.rt6_stats->fib_rt_entries, net->ipv6.rt6_stats->fib_rt_cache, dst_entries_get_slow(&net->ipv6.ip6_dst_ops), @@ -2798,46 +6500,36 @@ static int rt6_stats_seq_show(struct seq_file *seq, void *v) return 0; } - -static int rt6_stats_seq_open(struct inode *inode, struct file *file) -{ - return single_open_net(inode, file, rt6_stats_seq_show); -} - -static const struct file_operations rt6_stats_seq_fops = { - .owner = THIS_MODULE, - .open = rt6_stats_seq_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release_net, -}; #endif /* CONFIG_PROC_FS */ #ifdef CONFIG_SYSCTL -static -int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) +static int ipv6_sysctl_rtcache_flush(const struct ctl_table *ctl, int write, + void *buffer, size_t *lenp, loff_t *ppos) { struct net *net; int delay; + int ret; if (!write) return -EINVAL; + ret = proc_dointvec(ctl, write, buffer, lenp, ppos); + if (ret) + return ret; + net = (struct net *)ctl->extra1; delay = net->ipv6.sysctl.flush_delay; - proc_dointvec(ctl, write, buffer, lenp, ppos); - fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net); + fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0); return 0; } -struct ctl_table ipv6_route_table_template[] = { +static struct ctl_table ipv6_route_table_template[] = { { - .procname = "flush", - .data = &init_net.ipv6.sysctl.flush_delay, + .procname = "max_size", + .data = &init_net.ipv6.sysctl.ip6_rt_max_size, .maxlen = sizeof(int), - .mode = 0200, - .proc_handler = ipv6_sysctl_rtcache_flush + .mode = 0644, + .proc_handler = proc_dointvec, }, { .procname = "gc_thresh", @@ -2847,11 +6539,11 @@ struct ctl_table ipv6_route_table_template[] = { .proc_handler = proc_dointvec, }, { - .procname = "max_size", - .data = &init_net.ipv6.sysctl.ip6_rt_max_size, + .procname = "flush", + .data = &init_net.ipv6.sysctl.flush_delay, .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, + .mode = 0200, + .proc_handler = ipv6_sysctl_rtcache_flush }, { .procname = "gc_min_interval", @@ -2902,7 +6594,15 @@ struct ctl_table ipv6_route_table_template[] = { .mode = 0644, .proc_handler = proc_dointvec_ms_jiffies, }, - { } + { + .procname = "skip_notify_on_dev_down", + .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down, + .maxlen = sizeof(u8), + .mode = 0644, + .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, }; struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) @@ -2914,10 +6614,10 @@ struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) GFP_KERNEL); if (table) { - table[0].data = &net->ipv6.sysctl.flush_delay; - table[0].extra1 = net; + table[0].data = &net->ipv6.sysctl.ip6_rt_max_size; table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh; - table[2].data = &net->ipv6.sysctl.ip6_rt_max_size; + table[2].data = &net->ipv6.sysctl.flush_delay; + table[2].extra1 = net; table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout; table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval; @@ -2925,14 +6625,20 @@ struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net) table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires; table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss; table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval; - - /* Don't export sysctls to unprivileged users */ - if (net->user_ns != &init_user_ns) - table[0].procname = NULL; + table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down; } return table; } + +size_t ipv6_route_sysctl_table_size(struct net *net) +{ + /* Don't export sysctls to unprivileged users */ + if (net->user_ns != &init_user_ns) + return 1; + + return ARRAY_SIZE(ipv6_route_table_template); +} #endif static int __net_init ip6_route_net_init(struct net *net) @@ -2945,51 +6651,59 @@ static int __net_init ip6_route_net_init(struct net *net) if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0) goto out_ip6_dst_ops; + net->ipv6.fib6_null_entry = fib6_info_alloc(GFP_KERNEL, true); + if (!net->ipv6.fib6_null_entry) + goto out_ip6_dst_entries; + memcpy(net->ipv6.fib6_null_entry, &fib6_null_entry_template, + sizeof(*net->ipv6.fib6_null_entry)); + net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template, sizeof(*net->ipv6.ip6_null_entry), GFP_KERNEL); if (!net->ipv6.ip6_null_entry) - goto out_ip6_dst_entries; - net->ipv6.ip6_null_entry->dst.path = - (struct dst_entry *)net->ipv6.ip6_null_entry; + goto out_fib6_null_entry; net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops; dst_init_metrics(&net->ipv6.ip6_null_entry->dst, ip6_template_metrics, true); + INIT_LIST_HEAD(&net->ipv6.ip6_null_entry->dst.rt_uncached); #ifdef CONFIG_IPV6_MULTIPLE_TABLES + net->ipv6.fib6_has_custom_rules = false; net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template, sizeof(*net->ipv6.ip6_prohibit_entry), GFP_KERNEL); if (!net->ipv6.ip6_prohibit_entry) goto out_ip6_null_entry; - net->ipv6.ip6_prohibit_entry->dst.path = - (struct dst_entry *)net->ipv6.ip6_prohibit_entry; net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops; dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst, ip6_template_metrics, true); + INIT_LIST_HEAD(&net->ipv6.ip6_prohibit_entry->dst.rt_uncached); net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template, sizeof(*net->ipv6.ip6_blk_hole_entry), GFP_KERNEL); if (!net->ipv6.ip6_blk_hole_entry) goto out_ip6_prohibit_entry; - net->ipv6.ip6_blk_hole_entry->dst.path = - (struct dst_entry *)net->ipv6.ip6_blk_hole_entry; net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops; dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst, ip6_template_metrics, true); + INIT_LIST_HEAD(&net->ipv6.ip6_blk_hole_entry->dst.rt_uncached); +#ifdef CONFIG_IPV6_SUBTREES + net->ipv6.fib6_routes_require_src = 0; +#endif #endif net->ipv6.sysctl.flush_delay = 0; - net->ipv6.sysctl.ip6_rt_max_size = 4096; + net->ipv6.sysctl.ip6_rt_max_size = INT_MAX; net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2; net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ; net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ; net->ipv6.sysctl.ip6_rt_gc_elasticity = 9; net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ; net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40; + net->ipv6.sysctl.skip_notify_on_dev_down = 0; - net->ipv6.ip6_rt_gc_expire = 30*HZ; + atomic_set(&net->ipv6.ip6_rt_gc_expire, 30*HZ); ret = 0; out: @@ -3001,6 +6715,8 @@ out_ip6_prohibit_entry: out_ip6_null_entry: kfree(net->ipv6.ip6_null_entry); #endif +out_fib6_null_entry: + kfree(net->ipv6.fib6_null_entry); out_ip6_dst_entries: dst_entries_destroy(&net->ipv6.ip6_dst_ops); out_ip6_dst_ops: @@ -3009,6 +6725,7 @@ out_ip6_dst_ops: static void __net_exit ip6_route_net_exit(struct net *net) { + kfree(net->ipv6.fib6_null_entry); kfree(net->ipv6.ip6_null_entry); #ifdef CONFIG_IPV6_MULTIPLE_TABLES kfree(net->ipv6.ip6_prohibit_entry); @@ -3020,8 +6737,16 @@ static void __net_exit ip6_route_net_exit(struct net *net) static int __net_init ip6_route_net_init_late(struct net *net) { #ifdef CONFIG_PROC_FS - proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops); - proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops); + if (!proc_create_net("ipv6_route", 0, net->proc_net, + &ipv6_route_seq_ops, + sizeof(struct ipv6_route_iter))) + return -ENOMEM; + + if (!proc_create_net_single("rt6_stats", 0444, net->proc_net, + rt6_stats_seq_show, NULL)) { + remove_proc_entry("ipv6_route", net->proc_net); + return -ENOMEM; + } #endif return 0; } @@ -3071,17 +6796,79 @@ static struct pernet_operations ip6_route_net_late_ops = { static struct notifier_block ip6_route_dev_notifier = { .notifier_call = ip6_route_dev_notify, - .priority = 0, + .priority = ADDRCONF_NOTIFY_PRIORITY - 10, +}; + +void __init ip6_route_init_special_entries(void) +{ + /* Registering of the loopback is done before this portion of code, + * the loopback reference in rt6_info will not be taken, do it + * manually for init_net */ + init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev; + init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev; + init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); + #ifdef CONFIG_IPV6_MULTIPLE_TABLES + init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev; + init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); + init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev; + init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); + #endif +} + +#if IS_BUILTIN(CONFIG_IPV6) +#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) +DEFINE_BPF_ITER_FUNC(ipv6_route, struct bpf_iter_meta *meta, struct fib6_info *rt) + +BTF_ID_LIST_SINGLE(btf_fib6_info_id, struct, fib6_info) + +static const struct bpf_iter_seq_info ipv6_route_seq_info = { + .seq_ops = &ipv6_route_seq_ops, + .init_seq_private = bpf_iter_init_seq_net, + .fini_seq_private = bpf_iter_fini_seq_net, + .seq_priv_size = sizeof(struct ipv6_route_iter), +}; + +static struct bpf_iter_reg ipv6_route_reg_info = { + .target = "ipv6_route", + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__ipv6_route, rt), + PTR_TO_BTF_ID_OR_NULL }, + }, + .seq_info = &ipv6_route_seq_info, +}; + +static int __init bpf_iter_register(void) +{ + ipv6_route_reg_info.ctx_arg_info[0].btf_id = *btf_fib6_info_id; + return bpf_iter_reg_target(&ipv6_route_reg_info); +} + +static void bpf_iter_unregister(void) +{ + bpf_iter_unreg_target(&ipv6_route_reg_info); +} +#endif +#endif + +static const struct rtnl_msg_handler ip6_route_rtnl_msg_handlers[] __initconst_or_module = { + {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWROUTE, + .doit = inet6_rtm_newroute, .flags = RTNL_FLAG_DOIT_UNLOCKED}, + {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELROUTE, + .doit = inet6_rtm_delroute, .flags = RTNL_FLAG_DOIT_UNLOCKED}, + {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETROUTE, + .doit = inet6_rtm_getroute, .flags = RTNL_FLAG_DOIT_UNLOCKED}, }; int __init ip6_route_init(void) { int ret; + int cpu; ret = -ENOMEM; ip6_dst_ops_template.kmem_cachep = kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0, - SLAB_HWCACHE_ALIGN, NULL); + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL); if (!ip6_dst_ops_template.kmem_cachep) goto out; @@ -3099,17 +6886,6 @@ int __init ip6_route_init(void) ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep; - /* Registering of the loopback is done before this portion of code, - * the loopback reference in rt6_info will not be taken, do it - * manually for init_net */ - init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev; - init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); - #ifdef CONFIG_IPV6_MULTIPLE_TABLES - init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev; - init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); - init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev; - init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); - #endif ret = fib6_init(); if (ret) goto out_register_subsys; @@ -3126,20 +6902,34 @@ int __init ip6_route_init(void) if (ret) goto fib6_rules_init; - ret = -ENOBUFS; - if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) || - __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) || - __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL)) + ret = rtnl_register_many(ip6_route_rtnl_msg_handlers); + if (ret < 0) goto out_register_late_subsys; ret = register_netdevice_notifier(&ip6_route_dev_notifier); if (ret) goto out_register_late_subsys; +#if IS_BUILTIN(CONFIG_IPV6) +#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) + ret = bpf_iter_register(); + if (ret) + goto out_register_late_subsys; +#endif +#endif + + for_each_possible_cpu(cpu) { + struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu); + + INIT_LIST_HEAD(&ul->head); + spin_lock_init(&ul->lock); + } + out: return ret; out_register_late_subsys: + rtnl_unregister_all(PF_INET6); unregister_pernet_subsys(&ip6_route_net_late_ops); fib6_rules_init: fib6_rules_cleanup(); @@ -3160,6 +6950,11 @@ out_kmem_cache: void ip6_route_cleanup(void) { +#if IS_BUILTIN(CONFIG_IPV6) +#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) + bpf_iter_unregister(); +#endif +#endif unregister_netdevice_notifier(&ip6_route_dev_notifier); unregister_pernet_subsys(&ip6_route_net_late_ops); fib6_rules_cleanup(); |