diff options
Diffstat (limited to 'net/ipv6/route.c')
| -rw-r--r-- | net/ipv6/route.c | 5948 |
1 files changed, 4381 insertions, 1567 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 4d30c96a819d..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> @@ -58,18 +56,25 @@ #include <net/xfrm.h> #include <net/netevent.h> #include <net/netlink.h> -#include <net/nexthop.h> +#include <net/rtnh.h> #include <net/lwtunnel.h> #include <net/ip_tunnels.h> #include <net/l3mdev.h> -#include <trace/events/fib6.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 = -3, RT6_NUD_FAIL_PROBE = -2, @@ -77,15 +82,17 @@ enum rt6_nud_state { RT6_NUD_SUCCEED = 1 }; -static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort); -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 net *net, struct sock *sk, struct sk_buff *skb); @@ -93,25 +100,29 @@ 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 void rt6_dst_from_metrics_check(struct rt6_info *rt); -static int rt6_score_route(struct rt6_info *rt, int oif, int strict); -static size_t rt6_nlmsg_size(struct rt6_info *rt); -static int rt6_fill_node(struct net *net, - struct sk_buff *skb, struct rt6_info *rt, - struct in6_addr *dst, struct in6_addr *src, +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, 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, struct net_device *dev); @@ -124,83 +135,69 @@ struct uncached_list { static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list); -static void rt6_uncached_list_add(struct rt6_info *rt) +void rt6_uncached_list_add(struct rt6_info *rt) { struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list); - rt->rt6i_uncached_list = ul; + rt->dst.rt_uncached_list = ul; spin_lock_bh(&ul->lock); - list_add_tail(&rt->rt6i_uncached, &ul->head); + list_add_tail(&rt->dst.rt_uncached, &ul->head); spin_unlock_bh(&ul->lock); } -static void rt6_uncached_list_del(struct rt6_info *rt) +void rt6_uncached_list_del(struct rt6_info *rt) { - if (!list_empty(&rt->rt6i_uncached)) { - struct uncached_list *ul = rt->rt6i_uncached_list; + if (!list_empty(&rt->dst.rt_uncached)) { + struct uncached_list *ul = rt->dst.rt_uncached_list; spin_lock_bh(&ul->lock); - list_del(&rt->rt6i_uncached); + list_del_init(&rt->dst.rt_uncached); spin_unlock_bh(&ul->lock); } } -static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev) +static void rt6_uncached_list_flush_dev(struct net_device *dev) { - struct net_device *loopback_dev = net->loopback_dev; int cpu; - if (dev == loopback_dev) - return; - for_each_possible_cpu(cpu) { struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu); - struct rt6_info *rt; + struct rt6_info *rt, *safe; + + if (list_empty(&ul->head)) + continue; spin_lock_bh(&ul->lock); - list_for_each_entry(rt, &ul->head, rt6i_uncached) { + 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; - if (rt_idev->dev == dev) { - rt->rt6i_idev = in6_dev_get(loopback_dev); + if (rt_idev && rt_idev->dev == dev) { + rt->rt6i_idev = in6_dev_get(blackhole_netdev); in6_dev_put(rt_idev); + handled = true; } if (rt_dev == dev) { - rt->dst.dev = loopback_dev; - dev_hold(rt->dst.dev); - dev_put(rt_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); } } -static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt) -{ - return dst_metrics_write_ptr(rt->dst.from); -} - -static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old) -{ - struct rt6_info *rt = (struct rt6_info *)dst; - - if (rt->rt6i_flags & RTF_PCPU) - return rt6_pcpu_cow_metrics(rt); - else if (rt->rt6i_flags & RTF_CACHE) - return NULL; - else - return dst_cow_metrics_generic(dst, old); -} - -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) @@ -208,26 +205,38 @@ 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) { - struct net_device *dev = dst->dev; - struct rt6_info *rt = (struct rt6_info *)dst; + const struct rt6_info *rt = dst_rt6_info(dst); + struct net_device *dev = dst_dev(dst); - daddr = choose_neigh_daddr(rt, NULL, daddr); + daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr); if (!daddr) return; if (dev->flags & (IFF_NOARP | IFF_LOOPBACK)) @@ -244,7 +253,7 @@ static struct dst_ops ip6_dst_ops_template = { .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, @@ -252,46 +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 struct dst_ops ip6_dst_blackhole_ops = { - .family = AF_INET6, - .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 = dst_cow_metrics_generic, - .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, @@ -299,16 +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 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, @@ -316,14 +314,11 @@ 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, @@ -331,58 +326,25 @@ static const struct rt6_info ip6_blk_hole_entry_template = { .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) { - struct dst_entry *dst = &rt->dst; - - memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst)); - INIT_LIST_HEAD(&rt->rt6i_siblings); - INIT_LIST_HEAD(&rt->rt6i_uncached); + memset_after(rt, 0, dst); } /* allocate dst with ip6_dst_ops */ -static 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, - 1, DST_OBSOLETE_FORCE_CHK, flags); - - if (rt) - rt6_info_init(rt); - - return rt; -} - -struct rt6_info *ip6_dst_alloc(struct net *net, - struct net_device *dev, +struct rt6_info *ip6_dst_alloc(struct net *net, struct net_device *dev, int flags) { - struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags); + struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev, + DST_OBSOLETE_FORCE_CHK, flags); if (rt) { - rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC); - if (rt->rt6i_pcpu) { - int cpu; - - for_each_possible_cpu(cpu) { - struct rt6_info **p; - - p = per_cpu_ptr(rt->rt6i_pcpu, cpu); - /* no one shares rt */ - *p = NULL; - } - } else { - dst_release_immediate(&rt->dst); - return NULL; - } + rt6_info_init(rt); + atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc); } return rt; @@ -391,12 +353,11 @@ EXPORT_SYMBOL(ip6_dst_alloc); static void ip6_dst_destroy(struct dst_entry *dst) { - struct rt6_info *rt = (struct rt6_info *)dst; - struct dst_entry *from = dst->from; + struct rt6_info *rt = dst_rt6_info(dst); + struct fib6_info *from; struct inet6_dev *idev; - dst_destroy_metrics_generic(dst); - free_percpu(rt->rt6i_pcpu); + ip_dst_metrics_put(dst); rt6_uncached_list_del(rt); idev = rt->rt6i_idev; @@ -405,133 +366,265 @@ static void ip6_dst_destroy(struct dst_entry *dst) in6_dev_put(idev); } - dst->from = NULL; - dst_release(from); + 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 void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev) { - struct rt6_info *rt = (struct rt6_info *)dst; + struct rt6_info *rt = dst_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); - } + struct fib6_info *from; + + if (idev && idev->dev != blackhole_netdev) { + struct inet6_dev *blackhole_idev = in6_dev_get(blackhole_netdev); + + if (blackhole_idev) { + rt->rt6i_idev = blackhole_idev; + in6_dev_put(idev); } } + from = unrcu_pointer(xchg(&rt->from, NULL)); + fib6_info_release(from); } static bool __rt6_check_expired(const struct rt6_info *rt) { if (rt->rt6i_flags & RTF_EXPIRES) - return time_after(jiffies, rt->dst.expires); - else - return false; + 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; } -/* 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) +static struct fib6_info * +rt6_multipath_first_sibling_rcu(const struct fib6_info *rt) { - return get_hash_from_flowi6(fl6) % candidate_count; + 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; } -static struct rt6_info *rt6_multipath_select(struct rt6_info *match, - struct flowi6 *fl6, int oif, - int strict) +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) { - struct rt6_info *sibling, *next_sibling; - int route_choosen; + struct fib6_info *first, *match = res->f6i; + struct fib6_info *sibling; + int hash; + + if (!match->nh && (!match->fib6_nsiblings || have_oif_match)) + goto out; + + if (match->nh && have_oif_match && res->nh) + return; - 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 (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 (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 (!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; + + 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; + } + +out: + res->f6i = match; + res->nh = match->fib6_nh; } /* - * Route lookup. Any table->tb6_lock is implied. + * Route lookup. rcu_read_lock() should be held. */ -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 bool __rt6_device_match(struct net *net, const struct fib6_nh *nh, + const struct in6_addr *saddr, int oif, int flags) { - struct rt6_info *local = NULL; - struct rt6_info *sprt; + const struct net_device *dev; - if (!oif && ipv6_addr_any(saddr)) - goto out; + if (nh->fib_nh_flags & RTNH_F_DEAD) + return false; - 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) - continue; - if (local && - local->rt6i_idev->dev->ifindex == oif) - continue; - } - local = sprt; - } + 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; +} + +struct fib6_nh_dm_arg { + struct net *net; + const struct in6_addr *saddr; + int oif; + int flags; + struct fib6_nh *nh; +}; + +static int __rt6_nh_dev_match(struct fib6_nh *nh, void *_arg) +{ + struct fib6_nh_dm_arg *arg = _arg; + + arg->nh = nh; + return __rt6_device_match(arg->net, nh, arg->saddr, arg->oif, + arg->flags); +} + +/* 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 (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 (flags & RT6_LOOKUP_F_IFACE) - return net->ipv6.ip6_null_entry; + 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 @@ -539,6 +632,7 @@ 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) @@ -549,14 +643,19 @@ static void rt6_probe_deferred(struct work_struct *w) addrconf_addr_solict_mult(&work->target, &mcaddr); ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0); - dev_put(work->dev); + netdev_put(work->dev, &work->dev_tracker); kfree(work); } -static void rt6_probe(struct rt6_info *rt) +static void rt6_probe(struct fib6_nh *fib6_nh) { - struct __rt6_probe_work *work; + 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 @@ -565,42 +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) { - if (neigh->nud_state & NUD_VALID) + if (READ_ONCE(neigh->nud_state) & NUD_VALID) goto out; - work = NULL; - write_lock(&neigh->lock); + write_lock_bh(&neigh->lock); if (!(neigh->nud_state & NUD_VALID) && time_after(jiffies, neigh->updated + - rt->rt6i_idev->cnf.rtr_probe_interval)) { + READ_ONCE(idev->cnf.rtr_probe_interval))) { work = kmalloc(sizeof(*work), GFP_ATOMIC); if (work) __neigh_set_probe_once(neigh); } - write_unlock(&neigh->lock); - } else { + 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); } - if (work) { + if (!work || cmpxchg(&fib6_nh->last_probe, + last_probe, jiffies) != last_probe) { + kfree(work); + } else { INIT_WORK(&work->work, rt6_probe_deferred); - work->target = rt->rt6i_gateway; - dev_hold(rt->dst.dev); - work->dev = rt->dst.dev; + work->target = *nh_gw; + netdev_hold(dev, &work->dev_tracker, GFP_ATOMIC); + work->dev = dev; schedule_work(&work->work); } out: - rcu_read_unlock_bh(); + rcu_read_unlock(); } #else -static inline void rt6_probe(struct rt6_info *rt) +static inline void rt6_probe(struct fib6_nh *fib6_nh) { } #endif @@ -608,85 +717,72 @@ 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) -{ - 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) +static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh) { - 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_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; - struct inet6_dev *idev = rt->rt6i_idev; - struct net_device *dev = rt->dst.dev; + bool rc = false; + int m; - if (dev && !netif_carrier_ok(dev) && - idev->cnf.ignore_routes_with_linkdown && - !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE)) + if (nh->fib_nh_flags & RTNH_F_DEAD) goto out; - if (rt6_check_expired(rt)) + 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(rt, oif, strict); + 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 */ @@ -695,86 +791,175 @@ static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, } 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, *cont; - int mpri = -1; + struct fib6_nh_frl_arg *arg = _arg; - match = NULL; - cont = NULL; - for (rt = rr_head; rt; rt = rt->dst.rt6_next) { - if (rt->rt6i_metric != metric) { - cont = rt; - break; - } + arg->nh = nh; + return find_match(nh, arg->flags, arg->oif, arg->strict, + arg->mpri, arg->do_rr); +} - match = find_match(rt, oif, strict, &mpri, match, 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 (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) { - if (rt->rt6i_metric != metric) { - cont = rt; - break; + 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; } - match = find_match(rt, oif, strict, &mpri, match, do_rr); + 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; + + __find_rr_leaf(rr_head, NULL, metric, res, &cont, + oif, strict, do_rr, &mpri); - if (match || !cont) - return match; + __find_rr_leaf(leaf, rr_head, metric, res, &cont, + oif, strict, do_rr, &mpri); - for (rt = cont; rt; rt = rt->dst.rt6_next) - match = find_match(rt, oif, strict, &mpri, match, do_rr); + 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; - rt0 = fn->rr_ptr; + /* make sure this function or its helpers sets f6i */ + res->f6i = NULL; + + if (!leaf || leaf == net->ipv6.fib6_null_entry) + goto out; + + 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 != rt0) - fn->rr_ptr = next; + 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); + } } - net = dev_net(rt0->dst.dev); - return match ? match : net->ipv6.ip6_null_entry; +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; + } } -static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt) +static bool rt6_is_gw_or_nonexthop(const struct fib6_result *res) { - return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY)); + return (res->f6i->fib6_flags & RTF_NONEXTHOP) || + res->nh->fib_nh_gw_family; } #ifdef CONFIG_IPV6_ROUTE_INFO @@ -784,9 +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; @@ -824,13 +1010,13 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, } if (rinfo->prefix_len == 0) - rt = rt6_get_dflt_router(gwaddr, dev); + 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; } @@ -838,31 +1024,180 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, 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 +/* + * 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; + struct fib6_node *pn, *sn; while (1) { if (fn->fn_flags & RTN_TL_ROOT) return NULL; - pn = fn->parent; - if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) - fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); + 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) @@ -870,43 +1205,112 @@ static struct fib6_node* fib6_backtrack(struct fib6_node *fn, } } -static struct rt6_info *ip6_pol_route_lookup(struct net *net, +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); - if (rt == net->ipv6.ip6_null_entry) { + 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; } - dst_use(&rt->dst, jiffies); - read_unlock_bh(&table->tb6_lock); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); + fib6_select_path(net, &res, fl6, fl6->flowi6_oif, + fl6->flowi6_oif != 0, skb, flags); - return rt; + /* 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: + 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) + 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, @@ -920,9 +1324,9 @@ 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); @@ -936,59 +1340,57 @@ EXPORT_SYMBOL(rt6_lookup); * Caller must hold dst before calling it. */ -static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info, - struct mx6_config *mxc, +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, mxc, extack); - 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), }; - struct mx6_config mxc = { .mx = NULL, }; + struct nl_info info = { .nl_net = net, }; - /* Hold dst to account for the reference from the fib6 tree */ - dst_hold(&rt->dst); - return __ip6_ins_rt(rt, &info, &mxc, NULL); + return __ip6_ins_rt(rt, &info, NULL); } -static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort, +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. */ - if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU)) - ort = (struct rt6_info *)ort->dst.from; - - rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0); + if (!fib6_info_hold_safe(f6i)) + return NULL; - if (!rt) + dev = ip6_rt_get_dev_rcu(res); + rt = ip6_dst_alloc(dev_net(dev), dev, 0); + if (!rt) { + fib6_info_release(f6i); return NULL; + } - ip6_rt_copy_init(rt, ort); + ip6_rt_copy_init(rt, res); rt->rt6i_flags |= RTF_CACHE; - rt->rt6i_metric = 0; - rt->dst.flags |= DST_HOST; rt->rt6i_dst.addr = *daddr; rt->rt6i_dst.plen = 128; - if (!rt6_is_gw_or_nonexthop(ort)) { - if (ort->rt6i_dst.plen != 128 && - ipv6_addr_equal(&ort->rt6i_dst.addr, daddr)) + 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) { @@ -1001,99 +1403,835 @@ static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort, return rt; } -static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt) +static struct rt6_info *ip6_rt_pcpu_alloc(const struct fib6_result *res) { + struct fib6_info *f6i = res->f6i; + unsigned short flags = fib6_info_dst_flags(f6i); + struct net_device *dev; struct rt6_info *pcpu_rt; - pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev), - rt->dst.dev, rt->dst.flags); + if (!fib6_info_hold_safe(f6i)) + return NULL; - if (!pcpu_rt) + 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, rt); - pcpu_rt->rt6i_protocol = rt->rt6i_protocol; + } + 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; } -/* It should be called with read_lock_bh(&tb6_lock) acquired */ -static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt) +static bool rt6_is_valid(const struct rt6_info *rt6) +{ + return rt6->sernum == rt_genid_ipv6(dev_net(rt6->dst.dev)); +} + +/* 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, **p; + struct rt6_info *pcpu_rt; + + pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu); - p = this_cpu_ptr(rt->rt6i_pcpu); - pcpu_rt = *p; + if (pcpu_rt && pcpu_rt->sernum && !rt6_is_valid(pcpu_rt)) { + struct rt6_info *prev, **p; + + 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); + } - if (pcpu_rt) { - dst_hold(&pcpu_rt->dst); - rt6_dst_from_metrics_check(pcpu_rt); + pcpu_rt = NULL; } + return pcpu_rt; } -static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt) +static struct rt6_info *rt6_make_pcpu_route(struct net *net, + const struct fib6_result *res) { - struct fib6_table *table = rt->rt6i_table; struct rt6_info *pcpu_rt, *prev, **p; - pcpu_rt = ip6_rt_pcpu_alloc(rt); - if (!pcpu_rt) { - struct net *net = dev_net(rt->dst.dev); + 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); - dst_hold(&net->ipv6.ip6_null_entry->dst); - return net->ipv6.ip6_null_entry; + if (res->f6i->fib6_destroying) { + struct fib6_info *from; + + from = unrcu_pointer(xchg(&pcpu_rt->from, NULL)); + fib6_info_release(from); } - read_lock_bh(&table->tb6_lock); - if (rt->rt6i_pcpu) { - p = this_cpu_ptr(rt->rt6i_pcpu); - prev = cmpxchg(p, NULL, pcpu_rt); - if (prev) { - /* If someone did it before us, return prev instead */ - dst_release_immediate(&pcpu_rt->dst); - pcpu_rt = prev; + 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; + + 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); + +#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 + bucket = rcu_dereference(nh->rt6i_exception_bucket); + + /* remove bucket flushed bit if set */ + if (bucket) { + unsigned long p = (unsigned long)bucket; + + p &= ~FIB6_EXCEPTION_BUCKET_FLUSHED; + bucket = (struct rt6_exception_bucket *)p; + } + + return bucket; +} + +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. + */ + 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: + 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); + } + + 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 { - /* rt has been removed from the fib6 tree - * before we have a chance to acquire the read_lock. - * In this case, don't brother to create a pcpu rt - * since rt is going away anyway. The next - * dst_check() will trigger a re-lookup. - */ - dst_release_immediate(&pcpu_rt->dst); - pcpu_rt = rt; + fib6_nh_flush_exceptions(f6i->fib6_nh, f6i); } - dst_hold(&pcpu_rt->dst); - rt6_dst_from_metrics_check(pcpu_rt); - read_unlock_bh(&table->tb6_lock); - return pcpu_rt; } -struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, - int oif, struct flowi6 *fl6, int flags) +/* 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) { - struct fib6_node *fn, *saved_fn; - struct rt6_info *rt; - int strict = 0; + const struct in6_addr *src_key = NULL; + struct rt6_exception_bucket *bucket; + struct rt6_exception *rt6_ex; + struct rt6_info *ret = NULL; - strict |= flags & RT6_LOOKUP_F_IFACE; - strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE; - if (net->ipv6.devconf_all->forwarding == 0) - strict |= RT6_LOOKUP_F_REACHABLE; +#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); - read_lock_bh(&table->tb6_lock); + if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i)) + ret = rt6_ex->rt6i; - fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr); - saved_fn = fn; +#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 + }; - if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) - oif = 0; + 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: - rt = rt6_select(fn, oif, strict); - if (rt->rt6i_nsiblings) - rt = rt6_multipath_select(rt, fl6, oif, strict); - if (rt == net->ipv6.ip6_null_entry) { + 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; @@ -1105,95 +2243,380 @@ 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; - if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) { - dst_use(&rt->dst, jiffies); - read_unlock_bh(&table->tb6_lock); + rcu_read_lock(); - rt6_dst_from_metrics_check(rt); + fib6_table_lookup(net, table, oif, fl6, &res, strict); + if (res.f6i == net->ipv6.fib6_null_entry) + goto out; - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); - return rt; + 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) && - !(rt->rt6i_flags & RTF_GATEWAY))) { + !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); - struct rt6_info *uncached_rt; - - dst_use(&rt->dst, jiffies); - read_unlock_bh(&table->tb6_lock); - - uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL); - dst_release(&rt->dst); - - if (uncached_rt) { - /* Uncached_rt's refcnt is taken during ip6_rt_cache_alloc() - * No need for another dst_hold() + 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(uncached_rt); - } else { - uncached_rt = net->ipv6.ip6_null_entry; - dst_hold(&uncached_rt->dst); - } - - trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6); - return uncached_rt; + rt6_uncached_list_add(rt); + rcu_read_unlock(); + return rt; + } } else { /* Get a percpu copy */ + local_bh_disable(); + rt = rt6_get_pcpu_route(&res); - struct rt6_info *pcpu_rt; - - rt->dst.lastuse = jiffies; - rt->dst.__use++; - pcpu_rt = rt6_get_pcpu_route(rt); - - if (pcpu_rt) { - read_unlock_bh(&table->tb6_lock); - } else { - /* We have to do the read_unlock first - * because rt6_make_pcpu_route() may trigger - * ip6_dst_gc() which will take the write_lock. - */ - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); - pcpu_rt = rt6_make_pcpu_route(rt); - dst_release(&rt->dst); - } - - trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6); - return pcpu_rt; + 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); } struct dst_entry *ip6_route_input_lookup(struct net *net, struct net_device *dev, - struct flowi6 *fl6, int flags) + 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, @@ -1203,28 +2626,43 @@ 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; + + 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(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags)); + 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_flags(struct net *net, const struct sock *sk, - struct flowi6 *fl6, int flags) +static struct dst_entry *ip6_route_output_flags_noref(struct net *net, + const struct sock *sk, + struct flowi6 *fl6, + int flags) { bool any_src; - if (rt6_need_strict(&fl6->daddr)) { + 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; @@ -1232,6 +2670,7 @@ struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, fl6->flowi6_iif = LOOPBACK_IFINDEX; + 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)) @@ -1240,22 +2679,44 @@ struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk, 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); +} + +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, loopback_dev, 1, - DST_OBSOLETE_NONE, 0); + rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, + DST_OBSOLETE_DEAD, 0); if (rt) { rt6_info_init(rt); + atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc); new = &rt->dst; new->__use = 1; @@ -1267,7 +2728,6 @@ struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_ori rt->rt6i_idev = in6_dev_get(loopback_dev); rt->rt6i_gateway = ort->rt6i_gateway; rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU; - rt->rt6i_metric = 0; memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); #ifdef CONFIG_IPV6_SUBTREES @@ -1283,16 +2743,27 @@ struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_ori * Destination cache support functions */ -static void rt6_dst_from_metrics_check(struct rt6_info *rt) +static bool fib6_check(struct fib6_info *f6i, u32 cookie) { - if (rt->dst.from && - dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from)) - dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true); + 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, u32 cookie) +static struct dst_entry *rt6_check(struct rt6_info *rt, + struct fib6_info *from, + u32 cookie) { - if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie)) + u32 rt_cookie = 0; + + if (!from || !fib6_get_cookie_safe(from, &rt_cookie) || + rt_cookie != cookie) return NULL; if (rt6_check_expired(rt)) @@ -1301,52 +2772,68 @@ static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie) return &rt->dst; } -static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie) +static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, + struct fib6_info *from, + u32 cookie) { if (!__rt6_check_expired(rt) && - rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK && - rt6_check((struct rt6_info *)(rt->dst.from), cookie)) + READ_ONCE(rt->dst.obsolete) == DST_OBSOLETE_FORCE_CHK && + fib6_check(from, cookie)) return &rt->dst; - else - return NULL; + return NULL; } -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) { + 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. */ - rt6_dst_from_metrics_check(rt); + from = rcu_dereference(rt->from); - if (rt->rt6i_flags & RTF_PCPU || - (unlikely(!list_empty(&rt->rt6i_uncached)) && rt->dst.from)) - return rt6_dst_from_check(rt, cookie); + if (from && (rt->rt6i_flags & RTF_PCPU || + unlikely(!list_empty(&rt->dst.rt_uncached)))) + dst_ret = rt6_dst_from_check(rt, from, cookie); else - return rt6_check(rt, cookie); + 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) @@ -1355,43 +2842,68 @@ 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) { - if (dst_hold_safe(&rt->dst)) - ip6_del_rt(rt); - } 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 rt6_update_expires(struct rt6_info *rt0, int timeout) +{ + if (!(rt0->rt6i_flags & RTF_EXPIRES)) { + struct fib6_info *from; + + rcu_read_lock(); + from = rcu_dereference(rt0->from); + if (from) + WRITE_ONCE(rt0->dst.expires, from->expires); + rcu_read_unlock(); + } + + 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; - rt->rt6i_pmtu = mtu; 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 || rt->rt6i_node); + (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) + const struct ipv6hdr *iph, u32 mtu, + bool confirm_neigh) { const struct in6_addr *daddr, *saddr; - struct rt6_info *rt6 = (struct rt6_info *)dst; - - if (rt6->rt6i_flags & RTF_LOCAL) - return; + struct rt6_info *rt6 = dst_rt6_info(dst); - if (dst_metric_locked(dst, RTAX_MTU)) - return; + /* 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; @@ -1403,38 +2915,69 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk, daddr = NULL; saddr = NULL; } - dst_confirm_neigh(dst, daddr); - mtu = max_t(u32, mtu, IPV6_MIN_MTU); + + 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; - nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr); - if (nrt6) { - rt6_do_update_pmtu(nrt6, mtu); + rcu_read_lock(); + res.f6i = rcu_dereference(rt6->from); + if (!res.f6i) + goto out_unlock; - /* ip6_ins_rt(nrt6) will bump the - * rt6->rt6i_node->fn_sernum - * which will fail the next rt6_check() and - * invalidate the sk->sk_dst_cache. - */ - ip6_ins_rt(nrt6); - /* Release the reference taken in - * ip6_rt_cache_alloc() + 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. */ - dst_release(&nrt6->dst); + 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); + } +out_unlock: + rcu_read_unlock(); } } 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) { - __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu); + __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, @@ -1442,32 +2985,35 @@ void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu, { 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 ? mark : IP6_REPLY_MARK(net, skb->mark); - fl6.daddr = iph->daddr; - fl6.saddr = iph->saddr; - fl6.flowlabel = ip6_flowinfo(iph); - fl6.flowi6_uid = uid; + 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, iph, 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) { + int oif = sk->sk_bound_dev_if; struct dst_entry *dst; - ip6_update_pmtu(skb, sock_net(sk), mtu, - sk->sk_bound_dev_if, sk->sk_mark, sk->sk_uid); + 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 || !dst->obsolete || + if (!dst || !READ_ONCE(dst->obsolete) || dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) return; @@ -1478,19 +3024,89 @@ void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu) } EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu); +void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst, + const struct flowi6 *fl6) +{ +#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; }; -static struct rt6_info *__ip6_route_redirect(struct net *net, +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 *rt; + 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; /* Get the "current" route for this destination and @@ -1503,48 +3119,65 @@ static struct rt6_info *__ip6_route_redirect(struct net *net, * routes. */ - 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: - for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { - if (rt6_check_expired(rt)) + for_each_fib6_node_rt_rcu(fn) { + res.f6i = rt; + if (fib6_check_expired(rt)) continue; - if (rt->dst.error) + if (rt->fib6_flags & RTF_REJECT) break; - if (!(rt->rt6i_flags & RTF_GATEWAY)) - continue; - if (fl6->flowi6_oif != rt->dst.dev->ifindex) - continue; - if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway)) - continue; - 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.ip6_null_entry; - else if (rt->dst.error) { - rt = net->ipv6.ip6_null_entry; + 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.ip6_null_entry) { + 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: - dst_hold(&rt->dst); + 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); + } - read_unlock_bh(&table->tb6_lock); + rcu_read_unlock(); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); - return rt; + 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 in6_addr *gateway) + 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; @@ -1552,7 +3185,7 @@ static struct dst_entry *ip6_route_redirect(struct net *net, rdfl.fl6 = *fl6; rdfl.gateway = *gateway; - return fib6_rule_lookup(net, &rdfl.fl6, + return fib6_rule_lookup(net, &rdfl.fl6, skb, flags, __ip6_route_redirect); } @@ -1561,62 +3194,62 @@ void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark, { const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data; struct dst_entry *dst; - struct flowi6 fl6; - - memset(&fl6, 0, sizeof(fl6)); - fl6.flowi6_iif = LOOPBACK_IFINDEX; - fl6.flowi6_oif = oif; - fl6.flowi6_mark = mark; - fl6.daddr = iph->daddr; - fl6.saddr = iph->saddr; - fl6.flowlabel = ip6_flowinfo(iph); - fl6.flowi6_uid = uid; + 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, &ipv6_hdr(skb)->saddr); + 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, - u32 mark) +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; - - memset(&fl6, 0, sizeof(fl6)); - fl6.flowi6_iif = LOOPBACK_IFINDEX; - fl6.flowi6_oif = oif; - fl6.flowi6_mark = mark; - fl6.daddr = msg->dest; - fl6.saddr = iph->daddr; - fl6.flowi6_uid = sock_net_uid(net, NULL); + 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, &iph->saddr); + 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, - sk->sk_uid); + 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. @@ -1628,31 +3261,51 @@ 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) { - const struct rt6_info *rt = (const struct rt6_info *)dst; - unsigned int mtu = rt->rt6i_pmtu; - struct inet6_dev *idev; + return ip6_dst_mtu_maybe_forward(dst, false); +} +EXPORT_INDIRECT_CALLABLE(ip6_mtu); - if (mtu) - goto out; +/* 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; + struct rt6_info *rt; + u32 mtu = 0; - mtu = dst_metric_raw(dst, RTAX_MTU); - if (mtu) - goto out; + 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)); + } -out: mtu = min_t(unsigned int, mtu, IP6_MAX_MTU); - - return mtu - lwtunnel_headroom(dst->lwtstate, mtu); +out: + return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu); } struct dst_entry *icmp6_dst_alloc(struct net_device *dev, @@ -1673,7 +3326,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev, goto out; } - rt->dst.flags |= DST_HOST; + rt->dst.input = ip6_input; rt->dst.output = ip6_output; rt->rt6i_gateway = fl6->daddr; rt->rt6i_dst.addr = fl6->daddr; @@ -1681,7 +3334,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev, rt->rt6i_idev = idev; dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0); - /* Add this dst into uncached_list so that rt6_ifdown() can + /* Add this dst into uncached_list so that rt6_disable_ip() can * do proper release of the net_device */ rt6_uncached_list_add(rt); @@ -1692,163 +3345,452 @@ out: return dst; } -static int ip6_dst_gc(struct dst_ops *ops) +static void ip6_dst_gc(struct dst_ops *ops) { 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; + unsigned int val; int entries; - entries = dst_entries_get_fast(ops); - if (time_after(rt_last_gc + rt_min_interval, jiffies) && - entries <= rt_max_size) + if (time_after(rt_last_gc + rt_min_interval, jiffies)) goto out; - net->ipv6.ip6_rt_gc_expire++; - fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true); + 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) - net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1; + atomic_set(&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; + val = atomic_read(&net->ipv6.ip6_rt_gc_expire); + atomic_set(&net->ipv6.ip6_rt_gc_expire, val - (val >> rt_elasticity)); } -static int ip6_convert_metrics(struct mx6_config *mxc, - const struct fib6_config *cfg) +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) { - bool ecn_ca = false; - struct nlattr *nla; - int remaining; - u32 *mp; + struct flowi6 fl6 = { + .flowi6_oif = cfg->fc_ifindex, + .daddr = *gw_addr, + .saddr = cfg->fc_prefsrc, + }; + struct fib6_table *table; + int err; - if (!cfg->fc_mx) - return 0; + table = fib6_get_table(net, tbid); + if (!table) + return -EINVAL; - mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL); - if (unlikely(!mp)) - return -ENOMEM; + if (!ipv6_addr_any(&cfg->fc_prefsrc)) + flags |= RT6_LOOKUP_F_HAS_SADDR; - nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { - int type = nla_type(nla); - u32 val; + flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE; - if (!type) - continue; - if (unlikely(type > RTAX_MAX)) - goto err; + 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); - if (type == RTAX_CC_ALGO) { - char tmp[TCP_CA_NAME_MAX]; + return err; +} - nla_strlcpy(tmp, nla, sizeof(tmp)); - val = tcp_ca_get_key_by_name(tmp, &ecn_ca); - if (val == TCP_CA_UNSPEC) - goto err; - } else { - val = nla_get_u32(nla); - } - if (type == RTAX_HOPLIMIT && val > 255) - val = 255; - if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK)) - goto err; +static int ip6_route_check_nh_onlink(struct net *net, + struct fib6_config *cfg, + const struct net_device *dev, + struct netlink_ext_ack *extack) +{ + 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; - mp[type - 1] = val; - __set_bit(type - 1, mxc->mx_valid); + 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; } - if (ecn_ca) { - __set_bit(RTAX_FEATURES - 1, mxc->mx_valid); - mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA; + return err; +} + +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) +{ + 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; } - mxc->mx = mp; - return 0; - err: - kfree(mp); - return -EINVAL; + 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; + + 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; } -static struct rt6_info *ip6_nh_lookup_table(struct net *net, - struct fib6_config *cfg, - const struct in6_addr *gw_addr) +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) { - struct flowi6 fl6 = { - .flowi6_oif = cfg->fc_ifindex, - .daddr = *gw_addr, - .saddr = cfg->fc_prefsrc, - }; - struct fib6_table *table; - struct rt6_info *rt; - int flags = RT6_LOOKUP_F_IFACE | RT6_LOOKUP_F_IGNORE_LINKSTATE; + 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; - table = fib6_get_table(net, cfg->fc_table); - if (!table) - return NULL; + /* 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 (!ipv6_addr_any(&cfg->fc_prefsrc)) - flags |= RT6_LOOKUP_F_HAS_SADDR; + 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; + } - rt = ip6_pol_route(net, table, cfg->fc_ifindex, &fl6, flags); + rcu_read_lock(); - /* if table lookup failed, fall back to full lookup */ - if (rt == net->ipv6.ip6_null_entry) { - ip6_rt_put(rt); - rt = NULL; + if (cfg->fc_flags & RTNH_F_ONLINK) + err = ip6_route_check_nh_onlink(net, cfg, dev, extack); + else + err = ip6_route_check_nh(net, cfg, _dev, dev_tracker, + idev); + + rcu_read_unlock(); + + if (err) + goto out; } - return rt; + /* 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; + } + + err = 0; +out: + return err; } -static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg, - struct netlink_ext_ack *extack) +static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type) { - struct net *net = cfg->fc_nlinfo.nl_net; - struct rt6_info *rt = NULL; + if ((flags & RTF_REJECT) || + (dev && (dev->flags & IFF_LOOPBACK) && + !(addr_type & IPV6_ADDR_LOOPBACK) && + !(flags & (RTF_ANYCAST | RTF_LOCAL)))) + return true; + + return false; +} + +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) +{ + 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 = -EINVAL; + int err; + + 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) { + dev = netdev_get_by_index(net, cfg->fc_ifindex, + dev_tracker, gfp_flags); + if (!dev) + goto out; + idev = in6_dev_get(dev); + if (!idev) + goto out; + } + + 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 out; + 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 out; + goto errout; } + +#ifdef CONFIG_IPV6_SUBTREES if (cfg->fc_src_len > 128) { NL_SET_ERR_MSG(extack, "Invalid source address length"); - goto out; + 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; } -#ifndef CONFIG_IPV6_SUBTREES +#else if (cfg->fc_src_len) { NL_SET_ERR_MSG(extack, "Specifying source address requires IPV6_SUBTREES to be enabled"); - goto out; + goto errout; } #endif - if (cfg->fc_ifindex) { - err = -ENODEV; - dev = dev_get_by_index(net, cfg->fc_ifindex); - if (!dev) - goto out; - idev = in6_dev_get(dev); - if (!idev) - goto out; - } + return 0; +errout: + return -EINVAL; +} - if (cfg->fc_metric == 0) - cfg->fc_metric = IP6_RT_PRIO_USER; +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); @@ -1859,300 +3801,186 @@ static struct rt6_info *ip6_route_info_create(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, - (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT); - + 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); + 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; - 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->dst.output = ip6_output; - - if (cfg->fc_encap) { - struct lwtunnel_state *lwtstate; - - err = lwtunnel_build_state(cfg->fc_encap_type, - cfg->fc_encap, AF_INET6, cfg, - &lwtstate, extack); - if (err) - goto out; - rt->dst.lwtstate = lwtstate_get(lwtstate); - if (lwtunnel_output_redirect(rt->dst.lwtstate)) { - rt->dst.lwtstate->orig_output = rt->dst.output; - rt->dst.output = lwtunnel_output; - } - if (lwtunnel_input_redirect(rt->dst.lwtstate)) { - rt->dst.lwtstate->orig_input = rt->dst.input; - rt->dst.input = lwtunnel_input; - } - } - - 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; #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; - } - } - rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; - switch (cfg->fc_type) { - case RTN_BLACKHOLE: - rt->dst.error = -EINVAL; - rt->dst.output = dst_discard_out; - rt->dst.input = dst_discard; - break; - case RTN_PROHIBIT: - rt->dst.error = -EACCES; - rt->dst.output = ip6_pkt_prohibit_out; - rt->dst.input = ip6_pkt_prohibit; - break; - case RTN_THROW: - case RTN_UNREACHABLE: - default: - rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN - : (cfg->fc_type == RTN_UNREACHABLE) - ? -EHOSTUNREACH : -ENETUNREACH; - rt->dst.output = ip6_pkt_discard_out; - rt->dst.input = ip6_pkt_discard; - break; - } - goto install_route; - } + if (cfg->fc_nh_id) { + struct nexthop *nh; - if (cfg->fc_flags & RTF_GATEWAY) { - const struct in6_addr *gw_addr; - int gwa_type; + 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; + } - gw_addr = &cfg->fc_gateway; - gwa_type = ipv6_addr_type(gw_addr); + err = fib6_check_nexthop(nh, cfg, extack); + if (err) + goto out_free; - /* 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. - */ - err = -EINVAL; - if (ipv6_chk_addr_and_flags(net, gw_addr, - gwa_type & IPV6_ADDR_LINKLOCAL ? - dev : NULL, 0, 0)) { - NL_SET_ERR_MSG(extack, "Invalid gateway address"); - goto out; + if (!nexthop_get(nh)) { + NL_SET_ERR_MSG(extack, "Nexthop has been deleted"); + err = -ENOENT; + goto out_free; } - rt->rt6i_gateway = *gw_addr; - - if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { - struct rt6_info *grt = NULL; - - /* 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; - } - if (cfg->fc_table) { - grt = ip6_nh_lookup_table(net, cfg, gw_addr); + rt->nh = nh; + fib6_nh = nexthop_fib6_nh(rt->nh); - if (grt) { - if (grt->rt6i_flags & RTF_GATEWAY || - (dev && dev != grt->dst.dev)) { - ip6_rt_put(grt); - grt = NULL; - } - } - } + rcu_read_unlock(); + } else { + int addr_type; - if (!grt) - grt = rt6_lookup(net, gw_addr, NULL, - cfg->fc_ifindex, 1); + err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack); + if (err) + goto out_release; - 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); + fib6_nh = rt->fib6_nh; - if (err) - goto out; - } - 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; - } + /* 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; } - err = -ENODEV; - if (!dev) - goto out; - 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: - rt->dst.dev = dev; - rt->rt6i_idev = idev; - rt->rt6i_table = table; - - cfg->fc_nlinfo.nl_net = dev_net(dev); - - return rt; -out: - if (dev) - dev_put(dev); - if (idev) - in6_dev_put(idev); - if (rt) - dst_release_immediate(&rt->dst); + rt->fib6_prefsrc.addr = cfg->fc_prefsrc; + rt->fib6_prefsrc.plen = 128; + } - return ERR_PTR(err); + 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; } -int ip6_route_add(struct fib6_config *cfg, +int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags, struct netlink_ext_ack *extack) { - struct mx6_config mxc = { .mx = NULL, }; - struct rt6_info *rt; + struct fib6_info *rt; int err; - rt = ip6_route_info_create(cfg, extack); - if (IS_ERR(rt)) { - err = PTR_ERR(rt); - rt = NULL; - goto out; - } - - err = ip6_convert_metrics(&mxc, cfg); + err = fib6_config_validate(cfg, extack); if (err) - goto out; + return err; - err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc, extack); + rt = ip6_route_info_create(cfg, gfp_flags, extack); + if (IS_ERR(rt)) + return PTR_ERR(rt); - kfree(mxc.mx); + err = ip6_route_info_create_nh(rt, cfg, gfp_flags, extack); + if (err) + return err; - return err; -out: - if (rt) - dst_release_immediate(&rt->dst); + err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack); + fib6_info_release(rt); 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_del_rt_siblings(struct rt6_info *rt, 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; @@ -2160,20 +3988,21 @@ static int __ip6_del_rt_siblings(struct rt6_info *rt, struct fib6_config *cfg) struct fib6_table *table; int err = -ENOENT; - if (rt == net->ipv6.ip6_null_entry) + if (rt == net->ipv6.fib6_null_entry) goto out_put; - table = rt->rt6i_table; - write_lock_bh(&table->tb6_lock); + table = rt->fib6_table; + spin_lock_bh(&table->tb6_lock); - if (rt->rt6i_nsiblings && cfg->fc_delete_all_nh) { - struct rt6_info *sibling, *next_sibling; + 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, + if (rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0, RTM_DELROUTE, info->portid, seq, 0) < 0) { kfree_skb(skb); @@ -2182,9 +4011,35 @@ static int __ip6_del_rt_siblings(struct rt6_info *rt, struct fib6_config *cfg) 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->rt6i_siblings, - rt6i_siblings) { + &rt->fib6_siblings, + fib6_siblings) { err = fib6_del(sibling, info); if (err) goto out_unlock; @@ -2193,9 +4048,9 @@ static int __ip6_del_rt_siblings(struct rt6_info *rt, struct fib6_config *cfg) err = fib6_del(rt, info); out_unlock: - write_unlock_bh(&table->tb6_lock); + spin_unlock_bh(&table->tb6_lock); out_put: - ip6_rt_put(rt); + fib6_info_release(rt); if (skb) { rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE, @@ -2204,12 +4059,68 @@ out_put: 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); @@ -2218,39 +4129,75 @@ static int ip6_route_del(struct fib6_config *cfg, 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) { - if ((rt->rt6i_flags & RTF_CACHE) && - !(cfg->fc_flags & RTF_CACHE)) + 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)) - continue; - if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric) + !ipv6_addr_equal(&cfg->fc_gateway, &nh->fib_nh_gw6)) continue; - if (cfg->fc_protocol && cfg->fc_protocol != rt->rt6i_protocol) + if (!fib6_info_hold_safe(rt)) continue; - dst_hold(&rt->dst); - read_unlock_bh(&table->tb6_lock); /* if gateway was specified only delete the one hop */ if (cfg->fc_flags & RTF_GATEWAY) - return __ip6_del_rt(rt, &cfg->fc_nlinfo); - - return __ip6_del_rt_siblings(rt, cfg); + 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; } @@ -2259,6 +4206,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu { 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; @@ -2293,7 +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: @@ -2316,7 +4265,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu } } - rt = (struct rt6_info *) dst; + 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; @@ -2343,7 +4292,33 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu NEIGH_UPDATE_F_ISROUTER)), NDISC_REDIRECT, &ndopts); - nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL); + 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; + } + + 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; @@ -2353,8 +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)) - goto out_release; + /* 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; @@ -2362,59 +4340,13 @@ 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_release: - /* Release the reference taken in - * ip6_rt_cache_alloc() - */ - dst_release(&nrt->dst); - out: + rcu_read_unlock(); neigh_release(neigh); } -/* - * Misc support functions - */ - -static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from) -{ - BUG_ON(from->dst.from); - - rt->rt6i_flags &= ~RTF_EXPIRES; - dst_hold(&from->dst); - rt->dst.from = &from->dst; - dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true); -} - -static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort) -{ - rt->dst.input = ort->dst.input; - rt->dst.output = ort->dst.output; - rt->rt6i_dst = ort->rt6i_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; - rt6_set_from(rt, ort); - rt->rt6i_metric = ort->rt6i_metric; -#ifdef CONFIG_IPV6_SUBTREES - rt->rt6i_src = ort->rt6i_src; -#endif - rt->rt6i_prefsrc = ort->rt6i_prefsrc; - rt->rt6i_table = ort->rt6i_table; - rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate); -} - #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, struct net_device *dev) @@ -2422,34 +4354,39 @@ static struct rt6_info *rt6_get_route_info(struct net *net, 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, 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, struct net_device *dev, @@ -2461,12 +4398,14 @@ static struct rt6_info *rt6_add_route_info(struct net *net, .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_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO; cfg.fc_dst = *prefix; cfg.fc_gateway = *gwaddr; @@ -2474,53 +4413,68 @@ static struct rt6_info *rt6_add_route_info(struct net *net, if (!prefixlen) cfg.fc_flags |= RTF_DEFAULT; - ip6_route_add(&cfg, NULL); + ip6_route_add(&cfg, GFP_ATOMIC, NULL); 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) { u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT; - struct rt6_info *rt; + struct fib6_info *rt; struct fib6_table *table; - table = fib6_get_table(dev_net(dev), tb_id); + 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 = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT, - .fc_metric = IP6_RT_PRIO_USER, + .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; - if (!ip6_route_add(&cfg, NULL)) { + if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) { struct fib6_table *table; table = fib6_get_table(dev_net(dev), cfg.fc_table); @@ -2528,25 +4482,29 @@ struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr, 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 fib6_table *table) +static void __rt6_purge_dflt_routers(struct net *net, + struct fib6_table *table) { - struct rt6_info *rt; + struct fib6_info *rt; 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); + 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; } } - read_unlock_bh(&table->tb6_lock); + rcu_read_unlock(); table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER; } @@ -2563,7 +4521,7 @@ void rt6_purge_dflt_routers(struct net *net) 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(table); + __rt6_purge_dflt_routers(net, table); } } @@ -2574,59 +4532,50 @@ 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 = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ? - : 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, NULL); - break; - case SIOCDELRT: - err = ip6_route_del(&cfg, NULL); - 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; } /* @@ -2635,24 +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; } @@ -2663,7 +4629,7 @@ static int ip6_pkt_discard(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); } @@ -2674,7 +4640,7 @@ 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) { - skb->dev = skb_dst(skb)->dev; + skb->dev = skb_dst_dev(skb); return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); } @@ -2682,66 +4648,70 @@ static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff * 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) { - u32 tb_id; - struct net *net = dev_net(idev->dev); - struct net_device *dev = net->loopback_dev; - struct rt6_info *rt; - - /* use L3 Master device as loopback for host routes if device - * is enslaved and address is not link local or multicast - */ - if (!rt6_need_strict(addr)) - dev = l3mdev_master_dev_rcu(idev->dev) ? : dev; + 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; - rt = ip6_dst_alloc(net, dev, DST_NOCOUNT); - if (!rt) - 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_protocol = RTPROT_KERNEL; - 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_gateway = *addr; - rt->rt6i_dst.addr = *addr; - rt->rt6i_dst.plen = 128; - tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL; - rt->rt6i_table = fib6_get_table(net, tb_id); + if (!anycast && + (READ_ONCE(net->ipv6.devconf_all->disable_policy) || + READ_ONCE(idev->cnf.disable_policy))) + f6i->dst_nopolicy = true; - return rt; + 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; } @@ -2750,26 +4720,35 @@ 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, &adni); } -#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY) -#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE) +#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT) /* Remove routers and update dst entries when gateway turn into host. */ -static int fib6_clean_tohost(struct rt6_info *rt, void *arg) +static int fib6_clean_tohost(struct fib6_info *rt, void *arg) { struct in6_addr *gateway = (struct in6_addr *)arg; + struct fib6_nh *nh; + + /* RA routes do not use nexthops */ + if (rt->nh) + return 0; - if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) || - ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) && - ipv6_addr_equal(gateway, &rt->rt6i_gateway)) { + 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; } @@ -2778,45 +4757,292 @@ void rt6_clean_tohost(struct net *net, struct in6_addr *gateway) fib6_clean_all(net, fib6_clean_tohost, gateway); } -struct arg_dev_net { - struct net_device *dev; - struct net *net; +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_sync_up(struct net_device *dev, unsigned char nh_flags) +{ + struct arg_netdev_event arg = { + .dev = dev, + { + .nh_flags = nh_flags, + }, + }; + + 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 rt6_info *rt, void *arg) +static int fib6_ifdown(struct fib6_info *rt, void *p_arg) { - const struct arg_dev_net *adn = arg; - const struct net_device *dev = adn->dev; + const struct arg_netdev_event *arg = p_arg; + const struct net_device *dev = arg->dev; + struct net *net = dev_net(dev); - if ((rt->dst.dev == dev || !dev) && - rt != adn->net->ipv6.ip6_null_entry && - (rt->rt6i_nsiblings == 0 || - (dev && netdev_unregistering(dev)) || - !rt->rt6i_idev->cnf.ignore_routes_with_linkdown)) - return -1; + 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_ifdown(struct net *net, struct net_device *dev) +void rt6_sync_down_dev(struct net_device *dev, unsigned long event) { - struct arg_dev_net adn = { + struct arg_netdev_event arg = { .dev = dev, - .net = net, + { + .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); +} - fib6_clean_all(net, fib6_ifdown, &adn); - if (dev) - rt6_uncached_list_flush_dev(net, dev); +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; @@ -2831,38 +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 discovery. - */ - if (rt->dst.dev == arg->dev && - dst_metric_raw(&rt->dst, RTAX_MTU) && - !dst_metric_locked(&rt->dst, RTAX_MTU)) { - if (rt->rt6i_flags & RTF_CACHE) { - /* For RTF_CACHE with rt6i_pmtu == 0 - * (i.e. a redirected route), - * the metrics of its rt->dst.from has already - * been updated. - */ - if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu) - rt->rt6i_pmtu = arg->mtu; - } else if (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) @@ -2876,7 +5081,9 @@ void rt6_mtu_change(struct net_device *dev, unsigned int mtu) } 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 }, @@ -2888,32 +5095,103 @@ static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { [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 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, - NULL); + 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 || @@ -2927,14 +5205,26 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, if (rtm->rtm_flags & RTM_F_CLONED) cfg->fc_flags |= RTF_CACHE; - cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; - cfg->fc_nlinfo.nlh = nlh; - cfg->fc_nlinfo.nl_net = sock_net(skb->sk); + 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]) { 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; @@ -2975,8 +5265,7 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]); cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]); - err = lwtunnel_valid_encap_type_attr(cfg->fc_mp, - cfg->fc_mp_len, extack); + err = rtm_to_fib6_multipath_config(cfg, extack, newroute); if (err < 0) goto errout; } @@ -3015,52 +5304,36 @@ errout: } struct rt6_nh { - struct rt6_info *rt6_info; + struct fib6_info *fib6_info; struct fib6_config r_cfg; - struct mx6_config mxc; - struct list_head next; + struct list_head list; }; -static void ip6_print_replace_route_err(struct list_head *rt6_nh_list) -{ - struct rt6_nh *nh; - - list_for_each_entry(nh, rt6_nh_list, next) { - pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6c nexthop %pI6c ifi %d\n", - &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway, - nh->r_cfg.fc_ifindex); - } -} - static int ip6_route_info_append(struct list_head *rt6_nh_list, - struct rt6_info *rt, struct fib6_config *r_cfg) + struct fib6_info *rt, + struct fib6_config *r_cfg) { struct rt6_nh *nh; - int err = -EEXIST; - list_for_each_entry(nh, rt6_nh_list, next) { - /* check if rt6_info already exists */ - if (rt6_duplicate_nexthop(nh->rt6_info, rt)) - return err; + 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->rt6_info = rt; - err = ip6_convert_metrics(&nh->mxc, r_cfg); - if (err) { - kfree(nh); - return err; - } + + nh->fib6_info = rt; memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg)); - list_add_tail(&nh->next, rt6_nh_list); + list_add_tail(&nh->list, rt6_nh_list); return 0; } -static void ip6_route_mpath_notify(struct rt6_info *rt, - struct rt6_info *rt_last, +static void ip6_route_mpath_notify(struct fib6_info *rt, + struct fib6_info *rt_last, struct nl_info *info, __u16 nlflags) { @@ -3070,34 +5343,71 @@ static void ip6_route_mpath_notify(struct rt6_info *rt, * nexthop. Since sibling routes are always added at the end of * the list, find the first sibling of the last route appended */ - if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->rt6i_nsiblings) { - rt = list_first_entry(&rt_last->rt6i_siblings, - struct rt6_info, - rt6i_siblings); + 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 rt6_info *rt_notif = NULL, *rt_last = NULL; + 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; - struct rt6_info *rt; + LIST_HEAD(rt6_nh_list); struct rt6_nh *err_nh; - struct rt6_nh *nh, *nh_safe; + struct fib6_info *rt; __u16 nlflags; int remaining; int attrlen; - int err = 1; + int replace; int nhn = 0; - int replace = (cfg->fc_nlinfo.nlh && - (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE)); - LIST_HEAD(rt6_nh_list); + 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) @@ -3107,7 +5417,7 @@ static int ip6_route_multipath_add(struct fib6_config *cfg, rtnh = (struct rtnexthop *)cfg->fc_mp; /* Parse a Multipath Entry and build a list (rt6_nh_list) of - * rt6_info structs per nexthop + * fib6_info structs per nexthop */ while (rtnh_ok(rtnh, remaining)) { memcpy(&r_cfg, cfg, sizeof(*cfg)); @@ -3123,22 +5433,32 @@ static int ip6_route_multipath_add(struct fib6_config *cfg, 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); } - rt = ip6_route_info_create(&r_cfg, extack); + 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) { + 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) { - dst_release_immediate(&rt->dst); + fib6_info_release(rt); goto cleanup; } @@ -3151,22 +5471,28 @@ static int ip6_route_multipath_add(struct fib6_config *cfg, */ 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, next) { - rt_last = nh->rt6_info; - err = __ip6_ins_rt(nh->rt6_info, info, &nh->mxc, extack); - /* save reference to first route for notification */ - if (!rt_notif && !err) - rt_notif = nh->rt6_info; + list_for_each_entry(nh, &rt6_nh_list, list) { + err = __ip6_ins_rt(nh->fib6_info, info, extack); - /* nh->rt6_info is used or freed at this point, reset to NULL*/ - nh->rt6_info = NULL; if (err) { if (replace && nhn) - ip6_print_replace_route_err(&rt6_nh_list); + 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 * these flags after the first nexthop: if there is a collision, @@ -3175,11 +5501,37 @@ static int ip6_route_multipath_add(struct fib6_config *cfg, * nexthops have been replaced by first new, the rest should * be added to it. */ - cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL | - NLM_F_REPLACE); + 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; @@ -3193,18 +5545,16 @@ add_errout: ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags); /* Delete routes that were already added */ - list_for_each_entry(nh, &rt6_nh_list, next) { + 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, next) { - if (nh->rt6_info) - dst_release_immediate(&nh->rt6_info->dst); - kfree(nh->mxc.mx); - list_del(&nh->next); + list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, list) { + fib6_info_release(nh->fib6_info); + list_del(&nh->list); kfree(nh); } @@ -3216,9 +5566,10 @@ static int ip6_route_multipath_del(struct fib6_config *cfg, { struct fib6_config r_cfg; struct rtnexthop *rtnh; + int last_err = 0; int remaining; int attrlen; - int err = 1, last_err = 0; + int err; remaining = cfg->fc_mp_len; rtnh = (struct rtnexthop *)cfg->fc_mp; @@ -3235,10 +5586,11 @@ static int ip6_route_multipath_del(struct fib6_config *cfg, 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; } } + err = ip6_route_del(&r_cfg, extack); if (err) last_err = err; @@ -3259,9 +5611,20 @@ static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, if (err < 0) return err; - if (cfg.fc_mp) + 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 { + } else { cfg.fc_delete_all_nh = 1; return ip6_route_del(&cfg, extack); } @@ -3277,25 +5640,64 @@ static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, 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_add(&cfg, extack); else - return ip6_route_add(&cfg, extack); + return ip6_route_add(&cfg, GFP_KERNEL, extack); } -static size_t rt6_nlmsg_size(struct rt6_info *rt) +/* 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 = 0; + int *nexthop_len = arg; - if (rt->rt6i_nsiblings) { - nexthop_len = nla_total_size(0) /* RTA_MULTIPATH */ - + NLA_ALIGN(sizeof(struct rtnexthop)) - + nla_total_size(16) /* RTA_GATEWAY */ - + lwtunnel_get_encap_size(rt->dst.lwtstate); + *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */ + + NLA_ALIGN(sizeof(struct rtnexthop)) + + nla_total_size(16); /* RTA_GATEWAY */ - nexthop_len *= rt->rt6i_nsiblings; + 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 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 */ @@ -3309,59 +5711,31 @@ static size_t rt6_nlmsg_size(struct rt6_info *rt) + nla_total_size(sizeof(struct rta_cacheinfo)) + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */ + nla_total_size(1) /* RTA_PREF */ - + lwtunnel_get_encap_size(rt->dst.lwtstate) + nexthop_len; } -static int rt6_nexthop_info(struct sk_buff *skb, struct rt6_info *rt, - unsigned int *flags, bool skip_oif) +static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh, + unsigned char *flags) { - if (!netif_running(rt->dst.dev) || !netif_carrier_ok(rt->dst.dev)) { - *flags |= RTNH_F_LINKDOWN; - if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown) - *flags |= RTNH_F_DEAD; - } + if (nexthop_is_multipath(nh)) { + struct nlattr *mp; - if (rt->rt6i_flags & RTF_GATEWAY) { - if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0) + mp = nla_nest_start_noflag(skb, RTA_MULTIPATH); + if (!mp) goto nla_put_failure; - } - - /* not needed for multipath encoding b/c it has a rtnexthop struct */ - if (!skip_oif && rt->dst.dev && - nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex)) - goto nla_put_failure; - - if (rt->dst.lwtstate && - lwtunnel_fill_encap(skb, rt->dst.lwtstate) < 0) - goto nla_put_failure; - - return 0; - -nla_put_failure: - return -EMSGSIZE; -} - -/* add multipath next hop */ -static int rt6_add_nexthop(struct sk_buff *skb, struct rt6_info *rt) -{ - struct rtnexthop *rtnh; - unsigned int flags = 0; - - rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); - if (!rtnh) - goto nla_put_failure; - rtnh->rtnh_hops = 0; - rtnh->rtnh_ifindex = rt->dst.dev ? rt->dst.dev->ifindex : 0; - - if (rt6_nexthop_info(skb, rt, &flags, true) < 0) - goto nla_put_failure; + if (nexthop_mpath_fill_node(skb, nh, AF_INET6)) + goto nla_put_failure; - rtnh->rtnh_flags = flags; + nla_nest_end(skb, mp); + } else { + struct fib6_nh *fib6_nh; - /* length of rtnetlink header + attributes */ - rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; + 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; @@ -3369,79 +5743,61 @@ nla_put_failure: return -EMSGSIZE; } -static int rt6_fill_node(struct net *net, - struct sk_buff *skb, struct rt6_info *rt, - struct in6_addr *dst, struct in6_addr *src, +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) { - u32 metrics[RTAX_MAX]; - struct rtmsg *rtm; + 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; - long expires; - u32 table; + 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->rt6i_flags & RTF_ANYCAST) - rtm->rtm_type = RTN_ANYCAST; - 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_in6_addr(skb, RTA_DST, 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_in6_addr(skb, RTA_DST, &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) { @@ -3449,12 +5805,12 @@ static int rt6_fill_node(struct net *net, goto nla_put_failure; rtm->rtm_src_len = 128; } else if (rtm->rtm_src_len && - nla_put_in6_addr(skb, RTA_SRC, &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)) { + if (ipv6_addr_is_multicast(&rt6_dst->addr)) { int err = ip6mr_get_route(net, skb, rtm, portid); if (err == 0) @@ -3465,61 +5821,110 @@ static int rt6_fill_node(struct net *net, #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 && + 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; + saddr_buf = rt->fib6_prefsrc.addr; if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf)) goto nla_put_failure; } - memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics)); - if (rt->rt6i_pmtu) - metrics[RTAX_MTU - 1] = rt->rt6i_pmtu; - if (rtnetlink_put_metrics(skb, metrics) < 0) + pmetrics = dst ? dst_metrics_ptr(dst) : rt->fib6_metrics->metrics; + if (rtnetlink_put_metrics(skb, pmetrics) < 0) goto nla_put_failure; - if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric)) + 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 (rt->rt6i_nsiblings) { - struct rt6_info *sibling, *next_sibling; + 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(skb, RTA_MULTIPATH); + mp = nla_nest_start_noflag(skb, RTA_MULTIPATH); if (!mp) goto nla_put_failure; - if (rt6_add_nexthop(skb, rt) < 0) + if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common, + rt->fib6_nh->fib_nh_weight, AF_INET6, + 0) < 0) goto nla_put_failure; - list_for_each_entry_safe(sibling, next_sibling, - &rt->rt6i_siblings, rt6i_siblings) { - if (rt6_add_nexthop(skb, sibling) < 0) + 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 (rt6_nexthop_info(skb, rt, &rtm->rtm_flags, false) < 0) + 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 (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, &rt->dst, 0, expires, rt->dst.error) < 0) + if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0) goto nla_put_failure; - if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags))) + if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags))) goto nla_put_failure; @@ -3531,29 +5936,248 @@ nla_put_failure: 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; + 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.ip6_null_entry) - return 0; + if (rt == net->ipv6.fib6_null_entry) + return -1; - if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) { - struct rtmsg *rtm = nlmsg_data(arg->cb->nlh); + 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; + } - /* user wants prefix routes only */ - if (rtm->rtm_flags & RTM_F_PREFIX && - !(rt->rt6i_flags & RTF_PREFIX_RT)) { - /* success since this is not a prefix route */ - 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; + + 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(); + + if (err) + return count + w.count; + } + + return -1; +} + +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 rt6_fill_node(net, - arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, - NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq, - NLM_F_MULTI); + return 0; } static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, @@ -3562,22 +6186,21 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, 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; + struct flowi6 fl6 = {}; + __be32 flowlabel; bool fibmatch; - err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy, - extack); + 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); - fl6.flowlabel = ip6_make_flowinfo(rtm->rtm_tos, 0); fibmatch = !!(rtm->rtm_flags & RTM_F_FIB_MATCH); if (tb[RTA_SRC]) { @@ -3609,12 +6232,32 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, 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; } @@ -3624,19 +6267,17 @@ 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; - if (!fibmatch) - dst = 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; - if (!fibmatch) - dst = ip6_route_output(net, NULL, &fl6); + dst = ip6_route_output(net, NULL, &fl6); } - if (fibmatch) - dst = ip6_route_lookup(net, &fl6, 0); - rt = container_of(dst, struct rt6_info, dst); + rt = dst_rt6_info(dst); if (rt->dst.error) { err = rt->dst.error; ip6_rt_put(rt); @@ -3657,14 +6298,25 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, } skb_dst_set(skb, &rt->dst); - if (fibmatch) - err = rt6_fill_node(net, skb, rt, NULL, NULL, iif, - RTM_NEWROUTE, NETLINK_CB(in_skb).portid, - nlh->nlmsg_seq, 0); - else - err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif, - RTM_NEWROUTE, NETLINK_CB(in_skb).portid, - nlh->nlmsg_seq, 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; @@ -3675,23 +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; + 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, nlm_flags); + 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); @@ -3702,10 +6391,62 @@ 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) { @@ -3716,6 +6457,7 @@ static int ip6_route_dev_notify(struct notifier_block *this, 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 @@ -3729,10 +6471,10 @@ static int ip6_route_dev_notify(struct notifier_block *this, /* NETDEV_UNREGISTER could be fired for multiple times by * netdev_wait_allrefs(). Make sure we only call this once. */ - in6_dev_put(net->ipv6.ip6_null_entry->rt6i_idev); + in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev); #ifdef CONFIG_IPV6_MULTIPLE_TABLES - in6_dev_put(net->ipv6.ip6_prohibit_entry->rt6i_idev); - in6_dev_put(net->ipv6.ip6_blk_hole_entry->rt6i_idev); + in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev); + in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev); #endif } @@ -3744,22 +6486,13 @@ static int ip6_route_dev_notify(struct notifier_block *this, */ #ifdef CONFIG_PROC_FS - -static const struct file_operations ipv6_route_proc_fops = { - .owner = THIS_MODULE, - .open = ipv6_route_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_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), @@ -3767,46 +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 ? 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", @@ -3816,11 +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", @@ -3871,7 +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) @@ -3883,10 +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; @@ -3894,14 +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) @@ -3914,51 +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: @@ -3970,6 +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: @@ -3978,6 +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); @@ -3989,8 +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; } @@ -4048,6 +6804,7 @@ 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 @@ -4058,6 +6815,51 @@ void __init ip6_route_init_special_entries(void) #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; @@ -4066,7 +6868,7 @@ int __init ip6_route_init(void) 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; @@ -4100,16 +6902,22 @@ 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); @@ -4121,6 +6929,7 @@ 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(); @@ -4141,6 +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(); |