summaryrefslogtreecommitdiffstats
path: root/net/ipv6/route.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /net/ipv6/route.c
parentInitial commit. (diff)
downloadlinux-upstream/6.1.76.tar.xz
linux-upstream/6.1.76.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/ipv6/route.c')
-rw-r--r--net/ipv6/route.c6792
1 files changed, 6792 insertions, 0 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
new file mode 100644
index 000000000..7f65dc750
--- /dev/null
+++ b/net/ipv6/route.c
@@ -0,0 +1,6792 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux INET6 implementation
+ * FIB front-end.
+ *
+ * Authors:
+ * Pedro Roque <roque@di.fc.ul.pt>
+ */
+
+/* Changes:
+ *
+ * YOSHIFUJI Hideaki @USAGI
+ * reworked default router selection.
+ * - respect outgoing interface
+ * - select from (probably) reachable routers (i.e.
+ * routers in REACHABLE, STALE, DELAY or PROBE states).
+ * - always select the same router if it is (probably)
+ * reachable. otherwise, round-robin the list.
+ * Ville Nuorvala
+ * Fixed routing subtrees.
+ */
+
+#define pr_fmt(fmt) "IPv6: " fmt
+
+#include <linux/capability.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/types.h>
+#include <linux/times.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/route.h>
+#include <linux/netdevice.h>
+#include <linux/in6.h>
+#include <linux/mroute6.h>
+#include <linux/init.h>
+#include <linux/if_arp.h>
+#include <linux/proc_fs.h>
+#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>
+#include <net/ip6_fib.h>
+#include <net/ip6_route.h>
+#include <net/ndisc.h>
+#include <net/addrconf.h>
+#include <net/tcp.h>
+#include <linux/rtnetlink.h>
+#include <net/dst.h>
+#include <net/dst_metadata.h>
+#include <net/xfrm.h>
+#include <net/netevent.h>
+#include <net/netlink.h>
+#include <net/rtnh.h>
+#include <net/lwtunnel.h>
+#include <net/ip_tunnels.h>
+#include <net/l3mdev.h>
+#include <net/ip.h>
+#include <linux/uaccess.h>
+#include <linux/btf_ids.h>
+
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+
+static int ip6_rt_type_to_error(u8 fib6_type);
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/fib6.h>
+EXPORT_TRACEPOINT_SYMBOL_GPL(fib6_table_lookup);
+#undef CREATE_TRACE_POINTS
+
+enum rt6_nud_state {
+ RT6_NUD_FAIL_HARD = -3,
+ RT6_NUD_FAIL_PROBE = -2,
+ RT6_NUD_FAIL_DO_RR = -1,
+ RT6_NUD_SUCCEED = 1
+};
+
+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);
+INDIRECT_CALLABLE_SCOPE
+unsigned int ip6_mtu(const struct dst_entry *dst);
+static struct dst_entry *ip6_negative_advice(struct dst_entry *);
+static void ip6_dst_destroy(struct dst_entry *);
+static void ip6_dst_ifdown(struct dst_entry *,
+ struct net_device *dev, int how);
+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);
+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,
+ bool confirm_neigh);
+static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
+ struct sk_buff *skb);
+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 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 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);
+#endif
+
+struct uncached_list {
+ spinlock_t lock;
+ struct list_head head;
+ struct list_head quarantine;
+};
+
+static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
+
+void rt6_uncached_list_add(struct rt6_info *rt)
+{
+ struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
+
+ rt->rt6i_uncached_list = ul;
+
+ spin_lock_bh(&ul->lock);
+ list_add_tail(&rt->rt6i_uncached, &ul->head);
+ spin_unlock_bh(&ul->lock);
+}
+
+void rt6_uncached_list_del(struct rt6_info *rt)
+{
+ if (!list_empty(&rt->rt6i_uncached)) {
+ struct uncached_list *ul = rt->rt6i_uncached_list;
+
+ spin_lock_bh(&ul->lock);
+ list_del_init(&rt->rt6i_uncached);
+ spin_unlock_bh(&ul->lock);
+ }
+}
+
+static void rt6_uncached_list_flush_dev(struct net_device *dev)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
+ struct rt6_info *rt, *safe;
+
+ if (list_empty(&ul->head))
+ continue;
+
+ spin_lock_bh(&ul->lock);
+ list_for_each_entry_safe(rt, safe, &ul->head, rt6i_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(blackhole_netdev);
+ in6_dev_put(rt_idev);
+ handled = true;
+ }
+
+ if (rt_dev == dev) {
+ rt->dst.dev = blackhole_netdev;
+ netdev_ref_replace(rt_dev, blackhole_netdev,
+ &rt->dst.dev_tracker,
+ GFP_ATOMIC);
+ handled = true;
+ }
+ if (handled)
+ list_move(&rt->rt6i_uncached,
+ &ul->quarantine);
+ }
+ spin_unlock_bh(&ul->lock);
+ }
+}
+
+static inline const void *choose_neigh_daddr(const struct in6_addr *p,
+ struct sk_buff *skb,
+ const void *daddr)
+{
+ if (!ipv6_addr_any(p))
+ return (const void *) p;
+ else if (skb)
+ return &ipv6_hdr(skb)->daddr;
+ return daddr;
+}
+
+struct neighbour *ip6_neigh_lookup(const struct in6_addr *gw,
+ struct net_device *dev,
+ struct sk_buff *skb,
+ const void *daddr)
+{
+ struct neighbour *n;
+
+ daddr = choose_neigh_daddr(gw, skb, daddr);
+ n = __ipv6_neigh_lookup(dev, daddr);
+ if (n)
+ return n;
+
+ 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 = container_of(dst, struct rt6_info, dst);
+
+ return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any),
+ dst->dev, 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;
+
+ daddr = choose_neigh_daddr(rt6_nexthop(rt, &in6addr_any), NULL, daddr);
+ if (!daddr)
+ return;
+ if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
+ return;
+ if (ipv6_addr_is_multicast((const struct in6_addr *)daddr))
+ return;
+ __ipv6_confirm_neigh(dev, daddr);
+}
+
+static struct dst_ops ip6_dst_ops_template = {
+ .family = AF_INET6,
+ .gc = ip6_dst_gc,
+ .gc_thresh = 1024,
+ .check = ip6_dst_check,
+ .default_advmss = ip6_default_advmss,
+ .mtu = ip6_mtu,
+ .cow_metrics = dst_cow_metrics_generic,
+ .destroy = ip6_dst_destroy,
+ .ifdown = ip6_dst_ifdown,
+ .negative_advice = ip6_negative_advice,
+ .link_failure = ip6_link_failure,
+ .update_pmtu = ip6_rt_update_pmtu,
+ .redirect = rt6_do_redirect,
+ .local_out = __ip6_local_out,
+ .neigh_lookup = ip6_dst_neigh_lookup,
+ .confirm_neigh = ip6_confirm_neigh,
+};
+
+static struct dst_ops ip6_dst_blackhole_ops = {
+ .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),
+ .__use = 1,
+ .obsolete = DST_OBSOLETE_FORCE_CHK,
+ .error = -ENETUNREACH,
+ .input = ip6_pkt_discard,
+ .output = ip6_pkt_discard_out,
+ },
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+};
+
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+
+static const struct rt6_info ip6_prohibit_entry_template = {
+ .dst = {
+ .__refcnt = ATOMIC_INIT(1),
+ .__use = 1,
+ .obsolete = DST_OBSOLETE_FORCE_CHK,
+ .error = -EACCES,
+ .input = ip6_pkt_prohibit,
+ .output = ip6_pkt_prohibit_out,
+ },
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+};
+
+static const struct rt6_info ip6_blk_hole_entry_template = {
+ .dst = {
+ .__refcnt = ATOMIC_INIT(1),
+ .__use = 1,
+ .obsolete = DST_OBSOLETE_FORCE_CHK,
+ .error = -EINVAL,
+ .input = dst_discard,
+ .output = dst_discard_out,
+ },
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+};
+
+#endif
+
+static void rt6_info_init(struct rt6_info *rt)
+{
+ memset_after(rt, 0, dst);
+ INIT_LIST_HEAD(&rt->rt6i_uncached);
+}
+
+/* allocate dst with ip6_dst_ops */
+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);
+ atomic_inc(&net->ipv6.rt6_stats->fib_rt_alloc);
+ }
+
+ return rt;
+}
+EXPORT_SYMBOL(ip6_dst_alloc);
+
+static void ip6_dst_destroy(struct dst_entry *dst)
+{
+ struct rt6_info *rt = (struct rt6_info *)dst;
+ struct fib6_info *from;
+ struct inet6_dev *idev;
+
+ ip_dst_metrics_put(dst);
+ rt6_uncached_list_del(rt);
+
+ idev = rt->rt6i_idev;
+ if (idev) {
+ rt->rt6i_idev = NULL;
+ in6_dev_put(idev);
+ }
+
+ from = xchg((__force struct fib6_info **)&rt->from, NULL);
+ fib6_info_release(from);
+}
+
+static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
+ int how)
+{
+ struct rt6_info *rt = (struct rt6_info *)dst;
+ struct inet6_dev *idev = rt->rt6i_idev;
+
+ 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);
+ }
+ }
+}
+
+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;
+}
+
+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))
+ return true;
+ } else if (from) {
+ return rt->dst.obsolete != DST_OBSOLETE_FORCE_CHK ||
+ fib6_check_expired(from);
+ }
+ return false;
+}
+
+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 fib6_info *sibling, *next_sibling;
+ struct fib6_info *match = res->f6i;
+
+ if (!match->nh && (!match->fib6_nsiblings || have_oif_match))
+ goto out;
+
+ if (match->nh && have_oif_match && res->nh)
+ return;
+
+ if (skb)
+ IP6CB(skb)->flags |= IP6SKB_MULTIPATH;
+
+ /* We might have already computed the hash for ICMPv6 errors. In such
+ * case it will always be non-zero. Otherwise now is the time to do it.
+ */
+ if (!fl6->mp_hash &&
+ (!match->nh || nexthop_is_multipath(match->nh)))
+ fl6->mp_hash = rt6_multipath_hash(net, fl6, skb, NULL);
+
+ if (unlikely(match->nh)) {
+ nexthop_path_fib6_result(res, fl6->mp_hash);
+ return;
+ }
+
+ if (fl6->mp_hash <= atomic_read(&match->fib6_nh->fib_nh_upper_bound))
+ goto out;
+
+ list_for_each_entry_safe(sibling, next_sibling, &match->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 (fl6->mp_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. rcu_read_lock() should be held.
+ */
+
+static bool __rt6_device_match(struct net *net, const struct fib6_nh *nh,
+ const struct in6_addr *saddr, int oif, int flags)
+{
+ const struct net_device *dev;
+
+ if (nh->fib_nh_flags & RTNH_F_DEAD)
+ return false;
+
+ dev = nh->fib_nh_dev;
+ if (oif) {
+ if (dev->ifindex == oif)
+ return true;
+ } else {
+ if (ipv6_chk_addr(net, saddr, dev,
+ flags & RT6_LOOKUP_F_IFACE))
+ return true;
+ }
+
+ return false;
+}
+
+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 {
+ nh = f6i->fib6_nh;
+ }
+ if (!(nh->fib_nh_flags & RTNH_F_DEAD))
+ goto out;
+ }
+
+ 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 (nh->fib_nh_flags & RTNH_F_DEAD) {
+ res->f6i = net->ipv6.fib6_null_entry;
+ nh = res->f6i->fib6_nh;
+ }
+out:
+ 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
+struct __rt6_probe_work {
+ struct work_struct work;
+ struct in6_addr target;
+ struct net_device *dev;
+ netdevice_tracker dev_tracker;
+};
+
+static void rt6_probe_deferred(struct work_struct *w)
+{
+ struct in6_addr mcaddr;
+ struct __rt6_probe_work *work =
+ container_of(w, struct __rt6_probe_work, work);
+
+ addrconf_addr_solict_mult(&work->target, &mcaddr);
+ ndisc_send_ns(work->dev, &work->target, &mcaddr, NULL, 0);
+ netdev_put(work->dev, &work->dev_tracker);
+ kfree(work);
+}
+
+static void rt6_probe(struct fib6_nh *fib6_nh)
+{
+ struct __rt6_probe_work *work = NULL;
+ const struct in6_addr *nh_gw;
+ unsigned long last_probe;
+ struct neighbour *neigh;
+ struct net_device *dev;
+ struct inet6_dev *idev;
+
+ /*
+ * Okay, this does not seem to be appropriate
+ * for now, however, we need to check if it
+ * is really so; aka Router Reachability Probing.
+ *
+ * Router Reachability Probe MUST be rate-limited
+ * to no more than one per minute.
+ */
+ if (!fib6_nh->fib_nh_gw_family)
+ return;
+
+ 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);
+ neigh = __ipv6_neigh_lookup_noref(dev, nh_gw);
+ if (neigh) {
+ if (READ_ONCE(neigh->nud_state) & NUD_VALID)
+ goto out;
+
+ write_lock_bh(&neigh->lock);
+ if (!(neigh->nud_state & NUD_VALID) &&
+ time_after(jiffies,
+ neigh->updated + idev->cnf.rtr_probe_interval)) {
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ if (work)
+ __neigh_set_probe_once(neigh);
+ }
+ write_unlock_bh(&neigh->lock);
+ } else if (time_after(jiffies, last_probe +
+ idev->cnf.rtr_probe_interval)) {
+ work = kmalloc(sizeof(*work), GFP_ATOMIC);
+ }
+
+ if (!work || cmpxchg(&fib6_nh->last_probe,
+ last_probe, jiffies) != last_probe) {
+ kfree(work);
+ } else {
+ INIT_WORK(&work->work, rt6_probe_deferred);
+ work->target = *nh_gw;
+ netdev_hold(dev, &work->dev_tracker, GFP_ATOMIC);
+ work->dev = dev;
+ schedule_work(&work->work);
+ }
+
+out:
+ rcu_read_unlock();
+}
+#else
+static inline void rt6_probe(struct fib6_nh *fib6_nh)
+{
+}
+#endif
+
+/*
+ * Default Router Selection (RFC 2461 6.3.6)
+ */
+static enum rt6_nud_state rt6_check_neigh(const struct fib6_nh *fib6_nh)
+{
+ enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
+ struct neighbour *neigh;
+
+ rcu_read_lock();
+ neigh = __ipv6_neigh_lookup_noref(fib6_nh->fib_nh_dev,
+ &fib6_nh->fib_nh_gw6);
+ if (neigh) {
+ u8 nud_state = READ_ONCE(neigh->nud_state);
+
+ if (nud_state & NUD_VALID)
+ ret = RT6_NUD_SUCCEED;
+#ifdef CONFIG_IPV6_ROUTER_PREF
+ else if (!(nud_state & NUD_FAILED))
+ ret = RT6_NUD_SUCCEED;
+ else
+ ret = RT6_NUD_FAIL_PROBE;
+#endif
+ } else {
+ ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
+ RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
+ int strict)
+{
+ int m = 0;
+
+ if (!oif || nh->fib_nh_dev->ifindex == oif)
+ m = 2;
+
+ if (!m && (strict & RT6_LOOKUP_F_IFACE))
+ return RT6_NUD_FAIL_HARD;
+#ifdef CONFIG_IPV6_ROUTER_PREF
+ m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(fib6_flags)) << 2;
+#endif
+ 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 bool find_match(struct fib6_nh *nh, u32 fib6_flags,
+ int oif, int strict, int *mpri, bool *do_rr)
+{
+ bool match_do_rr = false;
+ bool rc = false;
+ int m;
+
+ if (nh->fib_nh_flags & RTNH_F_DEAD)
+ goto out;
+
+ if (ip6_ignore_linkdown(nh->fib_nh_dev) &&
+ nh->fib_nh_flags & RTNH_F_LINKDOWN &&
+ !(strict & RT6_LOOKUP_F_IGNORE_LINKSTATE))
+ goto out;
+
+ m = rt6_score_route(nh, fib6_flags, oif, strict);
+ if (m == RT6_NUD_FAIL_DO_RR) {
+ match_do_rr = true;
+ m = 0; /* lowest valid score */
+ } else if (m == RT6_NUD_FAIL_HARD) {
+ goto out;
+ }
+
+ if (strict & RT6_LOOKUP_F_REACHABLE)
+ 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;
+ rc = true;
+ }
+out:
+ return rc;
+}
+
+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 fib6_nh_frl_arg *arg = _arg;
+
+ arg->nh = nh;
+ return find_match(nh, arg->flags, arg->oif, arg->strict,
+ arg->mpri, arg->do_rr);
+}
+
+static void __find_rr_leaf(struct fib6_info *f6i_start,
+ struct fib6_info *nomatch, u32 metric,
+ struct fib6_result *res, struct fib6_info **cont,
+ int oif, int strict, bool *do_rr, int *mpri)
+{
+ struct fib6_info *f6i;
+
+ for (f6i = f6i_start;
+ f6i && f6i != nomatch;
+ f6i = rcu_dereference(f6i->fib6_next)) {
+ bool matched = false;
+ struct fib6_nh *nh;
+
+ if (cont && f6i->fib6_metric != metric) {
+ *cont = f6i;
+ return;
+ }
+
+ if (fib6_check_expired(f6i))
+ continue;
+
+ if (unlikely(f6i->nh)) {
+ struct fib6_nh_frl_arg arg = {
+ .flags = f6i->fib6_flags,
+ .oif = oif,
+ .strict = strict,
+ .mpri = mpri,
+ .do_rr = do_rr
+ };
+
+ if (nexthop_is_blackhole(f6i->nh)) {
+ res->fib6_flags = RTF_REJECT;
+ res->fib6_type = RTN_BLACKHOLE;
+ res->f6i = f6i;
+ res->nh = nexthop_fib6_nh(f6i->nh);
+ return;
+ }
+ if (nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_find_match,
+ &arg)) {
+ matched = true;
+ nh = arg.nh;
+ }
+ } else {
+ nh = f6i->fib6_nh;
+ if (find_match(nh, f6i->fib6_flags, oif, strict,
+ mpri, do_rr))
+ matched = true;
+ }
+ if (matched) {
+ res->f6i = f6i;
+ res->nh = nh;
+ res->fib6_flags = f6i->fib6_flags;
+ res->fib6_type = f6i->fib6_type;
+ }
+ }
+}
+
+static void find_rr_leaf(struct fib6_node *fn, struct fib6_info *leaf,
+ struct fib6_info *rr_head, int oif, int strict,
+ bool *do_rr, struct fib6_result *res)
+{
+ u32 metric = rr_head->fib6_metric;
+ struct fib6_info *cont = NULL;
+ int mpri = -1;
+
+ __find_rr_leaf(rr_head, NULL, metric, res, &cont,
+ oif, strict, do_rr, &mpri);
+
+ __find_rr_leaf(leaf, rr_head, metric, res, &cont,
+ oif, strict, do_rr, &mpri);
+
+ if (res->f6i || !cont)
+ return;
+
+ __find_rr_leaf(cont, NULL, metric, res, NULL,
+ oif, strict, do_rr, &mpri);
+}
+
+static void rt6_select(struct net *net, struct fib6_node *fn, int oif,
+ struct fib6_result *res, int strict)
+{
+ struct fib6_info *leaf = rcu_dereference(fn->leaf);
+ struct fib6_info *rt0;
+ bool do_rr = false;
+ int key_plen;
+
+ /* make sure this function or its helpers sets f6i */
+ res->f6i = NULL;
+
+ if (!leaf || leaf == net->ipv6.fib6_null_entry)
+ goto out;
+
+ rt0 = rcu_dereference(fn->rr_ptr);
+ if (!rt0)
+ rt0 = leaf;
+
+ /* 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 fib6_info *next = rcu_dereference(rt0->fib6_next);
+
+ /* no entries matched; do round-robin */
+ 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);
+ }
+ }
+
+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 fib6_result *res)
+{
+ return (res->f6i->fib6_flags & RTF_NONEXTHOP) ||
+ res->nh->fib_nh_gw_family;
+}
+
+#ifdef CONFIG_IPV6_ROUTE_INFO
+int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
+ const struct in6_addr *gwaddr)
+{
+ struct net *net = dev_net(dev);
+ struct route_info *rinfo = (struct route_info *) opt;
+ struct in6_addr prefix_buf, *prefix;
+ unsigned int pref;
+ unsigned long lifetime;
+ struct fib6_info *rt;
+
+ if (len < sizeof(struct route_info)) {
+ return -EINVAL;
+ }
+
+ /* Sanity check for prefix_len and length */
+ if (rinfo->length > 3) {
+ return -EINVAL;
+ } else if (rinfo->prefix_len > 128) {
+ return -EINVAL;
+ } else if (rinfo->prefix_len > 64) {
+ if (rinfo->length < 2) {
+ return -EINVAL;
+ }
+ } else if (rinfo->prefix_len > 0) {
+ if (rinfo->length < 1) {
+ return -EINVAL;
+ }
+ }
+
+ pref = rinfo->route_pref;
+ if (pref == ICMPV6_ROUTER_PREF_INVALID)
+ return -EINVAL;
+
+ lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
+
+ if (rinfo->length == 3)
+ prefix = (struct in6_addr *)rinfo->prefix;
+ else {
+ /* this function is safe */
+ ipv6_addr_prefix(&prefix_buf,
+ (struct in6_addr *)rinfo->prefix,
+ rinfo->prefix_len);
+ prefix = &prefix_buf;
+ }
+
+ if (rinfo->prefix_len == 0)
+ rt = rt6_get_dflt_router(net, gwaddr, dev);
+ else
+ rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
+ gwaddr, dev);
+
+ if (rt && !lifetime) {
+ ip6_del_rt(net, rt, false);
+ rt = NULL;
+ }
+
+ if (!rt && lifetime)
+ rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr,
+ dev, pref);
+ else if (rt)
+ rt->fib6_flags = RTF_ROUTEINFO |
+ (rt->fib6_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
+
+ if (rt) {
+ if (!addrconf_finite_timeout(lifetime))
+ fib6_clean_expires(rt);
+ else
+ fib6_set_expires(rt, jiffies + HZ * lifetime);
+
+ 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;
+ } else {
+ rt->dst.input = ip6_forward;
+ }
+
+ if (res->nh->fib_nh_lws) {
+ rt->dst.lwtstate = lwtstate_get(res->nh->fib_nh_lws);
+ lwtunnel_set_redirect(&rt->dst);
+ }
+
+ rt->dst.lastuse = jiffies;
+}
+
+/* Caller must already hold reference to @from */
+static void rt6_set_from(struct rt6_info *rt, struct fib6_info *from)
+{
+ rt->rt6i_flags &= ~RTF_EXPIRES;
+ rcu_assign_pointer(rt->from, from);
+ ip_dst_init_metrics(&rt->dst, from->fib6_metrics);
+}
+
+/* Caller must already hold reference to f6i in result */
+static void ip6_rt_copy_init(struct rt6_info *rt, const struct fib6_result *res)
+{
+ const struct fib6_nh *nh = res->nh;
+ const struct net_device *dev = nh->fib_nh_dev;
+ struct fib6_info *f6i = res->f6i;
+
+ ip6_rt_init_dst(rt, res);
+
+ rt->rt6i_dst = f6i->fib6_dst;
+ rt->rt6i_idev = dev ? in6_dev_get(dev) : NULL;
+ rt->rt6i_flags = res->fib6_flags;
+ if (nh->fib_nh_gw_family) {
+ rt->rt6i_gateway = nh->fib_nh_gw6;
+ rt->rt6i_flags |= RTF_GATEWAY;
+ }
+ rt6_set_from(rt, f6i);
+#ifdef CONFIG_IPV6_SUBTREES
+ rt->rt6i_src = f6i->fib6_src;
+#endif
+}
+
+static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
+ struct in6_addr *saddr)
+{
+ struct fib6_node *pn, *sn;
+ while (1) {
+ if (fn->fn_flags & RTN_TL_ROOT)
+ return NULL;
+ pn = rcu_dereference(fn->parent);
+ sn = FIB6_SUBTREE(pn);
+ if (sn && sn != fn)
+ fn = fib6_node_lookup(sn, NULL, saddr);
+ else
+ fn = pn;
+ if (fn->fn_flags & RTN_RTINFO)
+ return fn;
+ }
+}
+
+static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
+{
+ struct rt6_info *rt = *prt;
+
+ if (dst_hold_safe(&rt->dst))
+ return true;
+ if (net) {
+ rt = net->ipv6.ip6_null_entry;
+ dst_hold(&rt->dst);
+ } else {
+ rt = NULL;
+ }
+ *prt = rt;
+ return false;
+}
+
+/* called with rcu_lock held */
+static struct rt6_info *ip6_create_rt_rcu(const struct fib6_result *res)
+{
+ struct net_device *dev = res->nh->fib_nh_dev;
+ struct fib6_info *f6i = res->f6i;
+ unsigned short flags;
+ struct rt6_info *nrt;
+
+ if (!fib6_info_hold_safe(f6i))
+ goto fallback;
+
+ flags = fib6_info_dst_flags(f6i);
+ nrt = ip6_dst_alloc(dev_net(dev), dev, flags);
+ if (!nrt) {
+ fib6_info_release(f6i);
+ goto fallback;
+ }
+
+ ip6_rt_copy_init(nrt, res);
+ return nrt;
+
+fallback:
+ nrt = dev_net(dev)->ipv6.ip6_null_entry;
+ dst_hold(&nrt->dst);
+ return nrt;
+}
+
+INDIRECT_CALLABLE_SCOPE struct rt6_info *ip6_pol_route_lookup(struct net *net,
+ struct fib6_table *table,
+ struct flowi6 *fl6,
+ const struct sk_buff *skb,
+ int flags)
+{
+ struct fib6_result res = {};
+ struct fib6_node *fn;
+ struct rt6_info *rt;
+
+ rcu_read_lock();
+ fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
+restart:
+ res.f6i = rcu_dereference(fn->leaf);
+ if (!res.f6i)
+ res.f6i = net->ipv6.fib6_null_entry;
+ else
+ rt6_device_match(net, &res, &fl6->saddr, fl6->flowi6_oif,
+ flags);
+
+ if (res.f6i == net->ipv6.fib6_null_entry) {
+ fn = fib6_backtrack(fn, &fl6->saddr);
+ if (fn)
+ goto restart;
+
+ rt = net->ipv6.ip6_null_entry;
+ dst_hold(&rt->dst);
+ goto out;
+ } else if (res.fib6_flags & RTF_REJECT) {
+ goto do_create;
+ }
+
+ fib6_select_path(net, &res, fl6, fl6->flowi6_oif,
+ fl6->flowi6_oif != 0, skb, flags);
+
+ /* Search through exception table */
+ rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
+ if (rt) {
+ if (ip6_hold_safe(net, &rt))
+ dst_use_noref(&rt->dst, jiffies);
+ } else {
+do_create:
+ rt = ip6_create_rt_rcu(&res);
+ }
+
+out:
+ 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,
+ const struct sk_buff *skb, int flags)
+{
+ 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,
+ const struct sk_buff *skb, int strict)
+{
+ struct flowi6 fl6 = {
+ .flowi6_oif = oif,
+ .daddr = *daddr,
+ };
+ struct dst_entry *dst;
+ int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
+
+ if (saddr) {
+ memcpy(&fl6.saddr, saddr, sizeof(*saddr));
+ flags |= RT6_LOOKUP_F_HAS_SADDR;
+ }
+
+ dst = fib6_rule_lookup(net, &fl6, skb, flags, ip6_pol_route_lookup);
+ if (dst->error == 0)
+ return (struct rt6_info *) dst;
+
+ dst_release(dst);
+
+ return NULL;
+}
+EXPORT_SYMBOL(rt6_lookup);
+
+/* ip6_ins_rt is called with FREE table->tb6_lock.
+ * It takes new route entry, the addition fails by any reason the
+ * route is released.
+ * Caller must hold dst before calling it.
+ */
+
+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->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 net *net, struct fib6_info *rt)
+{
+ struct nl_info info = { .nl_net = net, };
+
+ return __ip6_ins_rt(rt, &info, NULL);
+}
+
+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 (!fib6_info_hold_safe(f6i))
+ return NULL;
+
+ 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, res);
+ rt->rt6i_flags |= RTF_CACHE;
+ rt->rt6i_dst.addr = *daddr;
+ rt->rt6i_dst.plen = 128;
+
+ if (!rt6_is_gw_or_nonexthop(res)) {
+ if (f6i->fib6_dst.plen != 128 &&
+ ipv6_addr_equal(&f6i->fib6_dst.addr, daddr))
+ rt->rt6i_flags |= RTF_ANYCAST;
+#ifdef CONFIG_IPV6_SUBTREES
+ if (rt->rt6i_src.plen && saddr) {
+ rt->rt6i_src.addr = *saddr;
+ rt->rt6i_src.plen = 128;
+ }
+#endif
+ }
+
+ return 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;
+
+ if (!fib6_info_hold_safe(f6i))
+ return NULL;
+
+ rcu_read_lock();
+ dev = ip6_rt_get_dev_rcu(res);
+ pcpu_rt = ip6_dst_alloc(dev_net(dev), dev, flags | DST_NOCOUNT);
+ rcu_read_unlock();
+ if (!pcpu_rt) {
+ fib6_info_release(f6i);
+ return NULL;
+ }
+ ip6_rt_copy_init(pcpu_rt, res);
+ pcpu_rt->rt6i_flags |= RTF_PCPU;
+
+ if (f6i->nh)
+ pcpu_rt->sernum = rt_genid_ipv6(dev_net(dev));
+
+ return pcpu_rt;
+}
+
+static 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;
+
+ pcpu_rt = this_cpu_read(*res->nh->rt6i_pcpu);
+
+ if (pcpu_rt && pcpu_rt->sernum && !rt6_is_valid(pcpu_rt)) {
+ struct rt6_info *prev, **p;
+
+ p = this_cpu_ptr(res->nh->rt6i_pcpu);
+ prev = xchg(p, NULL);
+ if (prev) {
+ dst_dev_put(&prev->dst);
+ dst_release(&prev->dst);
+ }
+
+ pcpu_rt = NULL;
+ }
+
+ return pcpu_rt;
+}
+
+static struct rt6_info *rt6_make_pcpu_route(struct net *net,
+ const struct fib6_result *res)
+{
+ struct rt6_info *pcpu_rt, *prev, **p;
+
+ pcpu_rt = ip6_rt_pcpu_alloc(res);
+ if (!pcpu_rt)
+ return NULL;
+
+ p = this_cpu_ptr(res->nh->rt6i_pcpu);
+ prev = cmpxchg(p, NULL, pcpu_rt);
+ BUG_ON(prev);
+
+ if (res->f6i->fib6_destroying) {
+ struct fib6_info *from;
+
+ from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
+ fib6_info_release(from);
+ }
+
+ return pcpu_rt;
+}
+
+/* exception hash table implementation
+ */
+static DEFINE_SPINLOCK(rt6_exception_lock);
+
+/* Remove rt6_ex from hash table and free the memory
+ * Caller must hold rt6_exception_lock
+ */
+static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
+ struct rt6_exception *rt6_ex)
+{
+ struct fib6_info *from;
+ 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
+ */
+ from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL);
+ fib6_info_release(from);
+ 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 = 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 + prandom_u32_max(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);
+ 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)
+ nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_flush_exceptions,
+ f6i);
+ else
+ fib6_nh_flush_exceptions(f6i->fib6_nh, f6i);
+}
+
+/* Find cached rt in the hash table inside passed in rt
+ * Caller has to hold rcu_read_lock()
+ */
+static struct rt6_info *rt6_find_cached_rt(const struct fib6_result *res,
+ const struct in6_addr *daddr,
+ const struct in6_addr *saddr)
+{
+ const struct in6_addr *src_key = NULL;
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct rt6_info *ret = NULL;
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* fib6i_src.plen != 0 indicates f6i is in subtree
+ * and exception table is indexed by a hash of
+ * both fib6_dst and fib6_src.
+ * However, the src addr used to create the hash
+ * might not be exactly the passed in saddr which
+ * is a /128 addr from the flow.
+ * So we need to use f6i->fib6_src to redo lookup
+ * if the passed in saddr does not find anything.
+ * (See the logic in ip6_rt_cache_alloc() on how
+ * rt->rt6i_src is updated.)
+ */
+ if (res->f6i->fib6_src.plen)
+ src_key = saddr;
+find_ex:
+#endif
+ bucket = fib6_nh_get_excptn_bucket(res->nh, NULL);
+ rt6_ex = __rt6_find_exception_rcu(&bucket, daddr, src_key);
+
+ if (rt6_ex && !rt6_check_expired(rt6_ex->rt6i))
+ ret = rt6_ex->rt6i;
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* Use fib6_src as src_key and redo lookup */
+ if (!ret && src_key && src_key != &res->f6i->fib6_src.addr) {
+ src_key = &res->f6i->fib6_src.addr;
+ goto find_ex;
+ }
+#endif
+
+ return ret;
+}
+
+/* Remove the passed in cached rt from the hash table that contains it */
+static int fib6_nh_remove_exception(const struct fib6_nh *nh, int plen,
+ const struct rt6_info *rt)
+{
+ const struct in6_addr *src_key = NULL;
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ int err;
+
+ if (!rcu_access_pointer(nh->rt6i_exception_bucket))
+ return -ENOENT;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
+
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates 'from' is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (plen)
+ src_key = &rt->rt6i_src.addr;
+#endif
+ rt6_ex = __rt6_find_exception_spinlock(&bucket,
+ &rt->rt6i_dst.addr,
+ src_key);
+ if (rt6_ex) {
+ rt6_remove_exception(bucket, rt6_ex);
+ err = 0;
+ } else {
+ err = -ENOENT;
+ }
+
+ spin_unlock_bh(&rt6_exception_lock);
+ return err;
+}
+
+struct fib6_nh_excptn_arg {
+ struct rt6_info *rt;
+ int plen;
+};
+
+static int rt6_nh_remove_exception_rt(struct fib6_nh *nh, void *_arg)
+{
+ struct fib6_nh_excptn_arg *arg = _arg;
+ int err;
+
+ err = fib6_nh_remove_exception(nh, arg->plen, arg->rt);
+ if (err == 0)
+ return 1;
+
+ return 0;
+}
+
+static int rt6_remove_exception_rt(struct rt6_info *rt)
+{
+ struct fib6_info *from;
+
+ from = rcu_dereference(rt->from);
+ if (!from || !(rt->rt6i_flags & RTF_CACHE))
+ return -EINVAL;
+
+ if (from->nh) {
+ struct fib6_nh_excptn_arg arg = {
+ .rt = rt,
+ .plen = from->fib6_src.plen
+ };
+ int rc;
+
+ /* rc = 1 means an entry was found */
+ rc = nexthop_for_each_fib6_nh(from->nh,
+ rt6_nh_remove_exception_rt,
+ &arg);
+ return rc ? 0 : -ENOENT;
+ }
+
+ return fib6_nh_remove_exception(from->fib6_nh,
+ from->fib6_src.plen, rt);
+}
+
+/* Find rt6_ex which contains the passed in rt cache and
+ * refresh its stamp
+ */
+static void fib6_nh_update_exception(const struct fib6_nh *nh, int plen,
+ const struct rt6_info *rt)
+{
+ const struct in6_addr *src_key = NULL;
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+
+ bucket = fib6_nh_get_excptn_bucket(nh, NULL);
+#ifdef CONFIG_IPV6_SUBTREES
+ /* rt6i_src.plen != 0 indicates 'from' is in subtree
+ * and exception table is indexed by a hash of
+ * both rt6i_dst and rt6i_src.
+ * Otherwise, the exception table is indexed by
+ * a hash of only rt6i_dst.
+ */
+ if (plen)
+ src_key = &rt->rt6i_src.addr;
+#endif
+ rt6_ex = __rt6_find_exception_rcu(&bucket, &rt->rt6i_dst.addr, src_key);
+ if (rt6_ex)
+ rt6_ex->stamp = jiffies;
+}
+
+struct fib6_nh_match_arg {
+ const struct net_device *dev;
+ const struct in6_addr *gw;
+ struct fib6_nh *match;
+};
+
+/* determine if fib6_nh has given device and gateway */
+static int fib6_nh_find_match(struct fib6_nh *nh, void *_arg)
+{
+ struct fib6_nh_match_arg *arg = _arg;
+
+ if (arg->dev != nh->fib_nh_dev ||
+ (arg->gw && !nh->fib_nh_gw_family) ||
+ (!arg->gw && nh->fib_nh_gw_family) ||
+ (arg->gw && !ipv6_addr_equal(arg->gw, &nh->fib_nh_gw6)))
+ return 0;
+
+ arg->match = nh;
+
+ /* found a match, break the loop */
+ return 1;
+}
+
+static void rt6_update_exception_stamp_rt(struct rt6_info *rt)
+{
+ struct fib6_info *from;
+ struct fib6_nh *fib6_nh;
+
+ rcu_read_lock();
+
+ from = rcu_dereference(rt->from);
+ if (!from || !(rt->rt6i_flags & RTF_CACHE))
+ goto unlock;
+
+ if (from->nh) {
+ struct fib6_nh_match_arg arg = {
+ .dev = rt->dst.dev,
+ .gw = &rt->rt6i_gateway,
+ };
+
+ nexthop_for_each_fib6_nh(from->nh, fib6_nh_find_match, &arg);
+
+ if (!arg.match)
+ goto unlock;
+ fib6_nh = arg.match;
+ } else {
+ fib6_nh = from->fib6_nh;
+ }
+ fib6_nh_update_exception(fib6_nh, from->fib6_src.plen, rt);
+unlock:
+ rcu_read_unlock();
+}
+
+static bool rt6_mtu_change_route_allowed(struct inet6_dev *idev,
+ struct rt6_info *rt, int mtu)
+{
+ /* If the new MTU is lower than the route PMTU, this new MTU will be the
+ * lowest MTU in the path: always allow updating the route PMTU to
+ * reflect PMTU decreases.
+ *
+ * If the new MTU is higher, and the route PMTU is equal to the local
+ * MTU, this means the old MTU is the lowest in the path, so allow
+ * updating it: if other nodes now have lower MTUs, PMTU discovery will
+ * handle this.
+ */
+
+ if (dst_mtu(&rt->dst) >= mtu)
+ return true;
+
+ if (dst_mtu(&rt->dst) == idev->cnf.mtu6)
+ return true;
+
+ return false;
+}
+
+static void rt6_exceptions_update_pmtu(struct inet6_dev *idev,
+ const struct fib6_nh *nh, int mtu)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ int i;
+
+ bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
+ if (!bucket)
+ return;
+
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry(rt6_ex, &bucket->chain, hlist) {
+ struct rt6_info *entry = rt6_ex->rt6i;
+
+ /* For RTF_CACHE with rt6i_pmtu == 0 (i.e. a redirected
+ * route), the metrics of its rt->from have already
+ * been updated.
+ */
+ if (dst_metric_raw(&entry->dst, RTAX_MTU) &&
+ rt6_mtu_change_route_allowed(idev, entry, mtu))
+ dst_metric_set(&entry->dst, RTAX_MTU, mtu);
+ }
+ bucket++;
+ }
+}
+
+#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
+
+static void fib6_nh_exceptions_clean_tohost(const struct fib6_nh *nh,
+ const struct in6_addr *gateway)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ if (!rcu_access_pointer(nh->rt6i_exception_bucket))
+ return;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp,
+ &bucket->chain, hlist) {
+ struct rt6_info *entry = rt6_ex->rt6i;
+
+ if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
+ RTF_CACHE_GATEWAY &&
+ ipv6_addr_equal(gateway,
+ &entry->rt6i_gateway)) {
+ rt6_remove_exception(bucket, rt6_ex);
+ }
+ }
+ bucket++;
+ }
+ }
+
+ spin_unlock_bh(&rt6_exception_lock);
+}
+
+static void rt6_age_examine_exception(struct rt6_exception_bucket *bucket,
+ struct rt6_exception *rt6_ex,
+ struct fib6_gc_args *gc_args,
+ unsigned long now)
+{
+ struct rt6_info *rt = rt6_ex->rt6i;
+
+ /* we are pruning and obsoleting aged-out and non gateway exceptions
+ * even if others have still references to them, so that on next
+ * dst_check() such references can be dropped.
+ * EXPIRES exceptions - e.g. pmtu-generated ones are pruned when
+ * expired, independently from their aging, as per RFC 8201 section 4
+ */
+ if (!(rt->rt6i_flags & RTF_EXPIRES)) {
+ if (time_after_eq(now, rt->dst.lastuse + gc_args->timeout)) {
+ RT6_TRACE("aging clone %p\n", rt);
+ rt6_remove_exception(bucket, rt6_ex);
+ return;
+ }
+ } else if (time_after(jiffies, rt->dst.expires)) {
+ RT6_TRACE("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))) {
+ RT6_TRACE("purging route %p via non-router but gateway\n",
+ rt);
+ rt6_remove_exception(bucket, rt6_ex);
+ return;
+ }
+ }
+
+ gc_args->more++;
+}
+
+static void fib6_nh_age_exceptions(const struct fib6_nh *nh,
+ struct fib6_gc_args *gc_args,
+ unsigned long now)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ if (!rcu_access_pointer(nh->rt6i_exception_bucket))
+ return;
+
+ rcu_read_lock_bh();
+ spin_lock(&rt6_exception_lock);
+ bucket = fib6_nh_get_excptn_bucket(nh, &rt6_exception_lock);
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp,
+ &bucket->chain, hlist) {
+ rt6_age_examine_exception(bucket, rt6_ex,
+ gc_args, now);
+ }
+ bucket++;
+ }
+ }
+ spin_unlock(&rt6_exception_lock);
+ rcu_read_unlock_bh();
+}
+
+struct fib6_nh_age_excptn_arg {
+ struct fib6_gc_args *gc_args;
+ unsigned long now;
+};
+
+static int rt6_nh_age_exceptions(struct fib6_nh *nh, void *_arg)
+{
+ struct fib6_nh_age_excptn_arg *arg = _arg;
+
+ fib6_nh_age_exceptions(nh, arg->gc_args, arg->now);
+ return 0;
+}
+
+void rt6_age_exceptions(struct fib6_info *f6i,
+ struct fib6_gc_args *gc_args,
+ unsigned long now)
+{
+ if (f6i->nh) {
+ struct fib6_nh_age_excptn_arg arg = {
+ .gc_args = gc_args,
+ .now = now
+ };
+
+ nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_age_exceptions,
+ &arg);
+ } else {
+ fib6_nh_age_exceptions(f6i->fib6_nh, gc_args, now);
+ }
+}
+
+/* must be called with rcu lock held */
+int fib6_table_lookup(struct net *net, struct fib6_table *table, int oif,
+ struct flowi6 *fl6, struct fib6_result *res, int strict)
+{
+ struct fib6_node *fn, *saved_fn;
+
+ fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
+ saved_fn = fn;
+
+redo_rt6_select:
+ rt6_select(net, fn, oif, res, strict);
+ if (res->f6i == net->ipv6.fib6_null_entry) {
+ fn = fib6_backtrack(fn, &fl6->saddr);
+ if (fn)
+ goto redo_rt6_select;
+ else if (strict & RT6_LOOKUP_F_REACHABLE) {
+ /* also consider unreachable route */
+ strict &= ~RT6_LOOKUP_F_REACHABLE;
+ fn = saved_fn;
+ goto redo_rt6_select;
+ }
+ }
+
+ trace_fib6_table_lookup(net, res, table, fl6);
+
+ return 0;
+}
+
+struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
+ int oif, struct flowi6 *fl6,
+ const struct sk_buff *skb, int flags)
+{
+ struct fib6_result res = {};
+ struct rt6_info *rt = NULL;
+ int strict = 0;
+
+ WARN_ON_ONCE((flags & RT6_LOOKUP_F_DST_NOREF) &&
+ !rcu_read_lock_held());
+
+ strict |= flags & RT6_LOOKUP_F_IFACE;
+ strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE;
+ if (net->ipv6.devconf_all->forwarding == 0)
+ strict |= RT6_LOOKUP_F_REACHABLE;
+
+ rcu_read_lock();
+
+ fib6_table_lookup(net, table, oif, fl6, &res, strict);
+ if (res.f6i == net->ipv6.fib6_null_entry)
+ goto out;
+
+ fib6_select_path(net, &res, fl6, oif, false, skb, strict);
+
+ /*Search through exception table */
+ rt = rt6_find_cached_rt(&res, &fl6->daddr, &fl6->saddr);
+ if (rt) {
+ goto out;
+ } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
+ !res.nh->fib_nh_gw_family)) {
+ /* Create a RTF_CACHE clone which will not be
+ * owned by the fib6 tree. It is for the special case where
+ * the daddr in the skb during the neighbor look-up is different
+ * from the fl6->daddr used to look-up route here.
+ */
+ rt = ip6_rt_cache_alloc(&res, &fl6->daddr, NULL);
+
+ if (rt) {
+ /* 1 refcnt is taken during ip6_rt_cache_alloc().
+ * As rt6_uncached_list_add() does not consume refcnt,
+ * this refcnt is always returned to the caller even
+ * if caller sets RT6_LOOKUP_F_DST_NOREF flag.
+ */
+ rt6_uncached_list_add(rt);
+ rcu_read_unlock();
+
+ return rt;
+ }
+ } else {
+ /* Get a percpu copy */
+ local_bh_disable();
+ rt = rt6_get_pcpu_route(&res);
+
+ if (!rt)
+ rt = rt6_make_pcpu_route(net, &res);
+
+ local_bh_enable();
+ }
+out:
+ if (!rt)
+ rt = net->ipv6.ip6_null_entry;
+ if (!(flags & RT6_LOOKUP_F_DST_NOREF))
+ ip6_hold_safe(net, &rt);
+ rcu_read_unlock();
+
+ return rt;
+}
+EXPORT_SYMBOL_GPL(ip6_pol_route);
+
+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, skb, flags);
+}
+
+struct dst_entry *ip6_route_input_lookup(struct net *net,
+ struct net_device *dev,
+ struct flowi6 *fl6,
+ const struct sk_buff *skb,
+ int flags)
+{
+ if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
+ flags |= RT6_LOOKUP_F_IFACE;
+
+ return fib6_rule_lookup(net, fl6, 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 flow_hash_from_keys(&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 flow_hash_from_keys(&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)
+ hash_keys.ports.src = fl6->fl6_sport;
+ if (hash_fields & FIB_MULTIPATH_HASH_FIELD_DST_PORT)
+ hash_keys.ports.dst = fl6->fl6_dport;
+
+ return flow_hash_from_keys(&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 = flow_hash_from_keys(&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;
+ hash_keys.ports.src = fl6->fl6_sport;
+ hash_keys.ports.dst = fl6->fl6_dport;
+ hash_keys.basic.ip_proto = fl6->flowi6_proto;
+ }
+ mhash = flow_hash_from_keys(&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 = flow_hash_from_keys(&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 | RT6_LOOKUP_F_DST_NOREF;
+ struct ip_tunnel_info *tun_info;
+ struct flowi6 fl6 = {
+ .flowi6_iif = skb->dev->ifindex,
+ .daddr = iph->daddr,
+ .saddr = iph->saddr,
+ .flowlabel = ip6_flowinfo(iph),
+ .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_noref(skb, ip6_route_input_lookup(net, skb->dev,
+ &fl6, skb, 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, skb, flags);
+}
+
+struct dst_entry *ip6_route_output_flags_noref(struct net *net,
+ const struct sock *sk,
+ struct flowi6 *fl6, int flags)
+{
+ bool any_src;
+
+ if (ipv6_addr_type(&fl6->daddr) &
+ (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL)) {
+ struct dst_entry *dst;
+
+ /* This function does not take refcnt on the dst */
+ dst = l3mdev_link_scope_lookup(net, fl6);
+ if (dst)
+ return dst;
+ }
+
+ fl6->flowi6_iif = LOOPBACK_IFINDEX;
+
+ flags |= RT6_LOOKUP_F_DST_NOREF;
+ any_src = ipv6_addr_any(&fl6->saddr);
+ if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
+ (fl6->flowi6_oif && any_src))
+ flags |= RT6_LOOKUP_F_IFACE;
+
+ if (!any_src)
+ flags |= RT6_LOOKUP_F_HAS_SADDR;
+ else if (sk)
+ flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
+
+ return fib6_rule_lookup(net, fl6, NULL, flags, ip6_pol_route_output);
+}
+EXPORT_SYMBOL_GPL(ip6_route_output_flags_noref);
+
+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 = (struct rt6_info *)dst;
+ /* For dst cached in uncached_list, refcnt is already taken. */
+ if (list_empty(&rt6->rt6i_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 net_device *loopback_dev = net->loopback_dev;
+ struct dst_entry *new = NULL;
+
+ rt = dst_alloc(&ip6_dst_blackhole_ops, loopback_dev, 1,
+ 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;
+ new->input = dst_discard;
+ new->output = dst_discard_out;
+
+ dst_copy_metrics(new, &ort->dst);
+
+ rt->rt6i_idev = in6_dev_get(loopback_dev);
+ rt->rt6i_gateway = ort->rt6i_gateway;
+ rt->rt6i_flags = ort->rt6i_flags & ~RTF_PCPU;
+
+ memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
+#ifdef CONFIG_IPV6_SUBTREES
+ memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
+#endif
+ }
+
+ dst_release(dst_orig);
+ return new ? new : ERR_PTR(-ENOMEM);
+}
+
+/*
+ * Destination cache support functions
+ */
+
+static bool fib6_check(struct fib6_info *f6i, u32 cookie)
+{
+ u32 rt_cookie = 0;
+
+ if (!fib6_get_cookie_safe(f6i, &rt_cookie) || rt_cookie != cookie)
+ return false;
+
+ if (fib6_check_expired(f6i))
+ return false;
+
+ return true;
+}
+
+static struct dst_entry *rt6_check(struct rt6_info *rt,
+ struct fib6_info *from,
+ u32 cookie)
+{
+ u32 rt_cookie = 0;
+
+ if (!from || !fib6_get_cookie_safe(from, &rt_cookie) ||
+ rt_cookie != cookie)
+ return NULL;
+
+ if (rt6_check_expired(rt))
+ return NULL;
+
+ return &rt->dst;
+}
+
+static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt,
+ struct fib6_info *from,
+ u32 cookie)
+{
+ if (!__rt6_check_expired(rt) &&
+ rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
+ fib6_check(from, cookie))
+ return &rt->dst;
+ else
+ return NULL;
+}
+
+INDIRECT_CALLABLE_SCOPE struct dst_entry *ip6_dst_check(struct dst_entry *dst,
+ u32 cookie)
+{
+ struct dst_entry *dst_ret;
+ struct fib6_info *from;
+ struct rt6_info *rt;
+
+ rt = container_of(dst, struct 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.
+ */
+
+ from = rcu_dereference(rt->from);
+
+ if (from && (rt->rt6i_flags & RTF_PCPU ||
+ unlikely(!list_empty(&rt->rt6i_uncached))))
+ dst_ret = rt6_dst_from_check(rt, from, cookie);
+ else
+ dst_ret = rt6_check(rt, from, cookie);
+
+ rcu_read_unlock();
+
+ return dst_ret;
+}
+EXPORT_INDIRECT_CALLABLE(ip6_dst_check);
+
+static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
+{
+ struct rt6_info *rt = (struct rt6_info *) dst;
+
+ if (rt) {
+ if (rt->rt6i_flags & RTF_CACHE) {
+ rcu_read_lock();
+ if (rt6_check_expired(rt)) {
+ rt6_remove_exception_rt(rt);
+ dst = NULL;
+ }
+ rcu_read_unlock();
+ } else {
+ dst_release(dst);
+ dst = NULL;
+ }
+ }
+ return dst;
+}
+
+static void ip6_link_failure(struct sk_buff *skb)
+{
+ struct rt6_info *rt;
+
+ icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
+
+ rt = (struct rt6_info *) skb_dst(skb);
+ if (rt) {
+ rcu_read_lock();
+ if (rt->rt6i_flags & RTF_CACHE) {
+ 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)
+ 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;
+ rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
+}
+
+static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
+{
+ return !(rt->rt6i_flags & RTF_CACHE) &&
+ (rt->rt6i_flags & RTF_PCPU || rcu_access_pointer(rt->from));
+}
+
+static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
+ const struct ipv6hdr *iph, u32 mtu,
+ bool confirm_neigh)
+{
+ const struct in6_addr *daddr, *saddr;
+ struct rt6_info *rt6 = (struct rt6_info *)dst;
+
+ /* Note: do *NOT* check dst_metric_locked(dst, RTAX_MTU)
+ * IPv6 pmtu discovery isn't optional, so 'mtu lock' cannot disable it.
+ * [see also comment in rt6_mtu_change_route()]
+ */
+
+ if (iph) {
+ daddr = &iph->daddr;
+ saddr = &iph->saddr;
+ } else if (sk) {
+ daddr = &sk->sk_v6_daddr;
+ saddr = &inet6_sk(sk)->saddr;
+ } else {
+ daddr = NULL;
+ saddr = NULL;
+ }
+
+ if (confirm_neigh)
+ dst_confirm_neigh(dst, daddr);
+
+ if (mtu < IPV6_MIN_MTU)
+ return;
+ if (mtu >= dst_mtu(dst))
+ return;
+
+ if (!rt6_cache_allowed_for_pmtu(rt6)) {
+ rt6_do_update_pmtu(rt6, mtu);
+ /* update rt6_ex->stamp for cache */
+ if (rt6->rt6i_flags & RTF_CACHE)
+ rt6_update_exception_stamp_rt(rt6);
+ } else if (daddr) {
+ struct fib6_result res = {};
+ struct rt6_info *nrt6;
+
+ rcu_read_lock();
+ res.f6i = rcu_dereference(rt6->from);
+ if (!res.f6i)
+ goto out_unlock;
+
+ res.fib6_flags = res.f6i->fib6_flags;
+ res.fib6_type = res.f6i->fib6_type;
+
+ if (res.f6i->nh) {
+ struct fib6_nh_match_arg arg = {
+ .dev = dst->dev,
+ .gw = &rt6->rt6i_gateway,
+ };
+
+ nexthop_for_each_fib6_nh(res.f6i->nh,
+ fib6_nh_find_match, &arg);
+
+ /* fib6_info uses a nexthop that does not have fib6_nh
+ * using the dst->dev + gw. Should be impossible.
+ */
+ if (!arg.match)
+ goto out_unlock;
+
+ res.nh = arg.match;
+ } else {
+ res.nh = res.f6i->fib6_nh;
+ }
+
+ nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr);
+ if (nrt6) {
+ rt6_do_update_pmtu(nrt6, mtu);
+ if (rt6_insert_exception(nrt6, &res))
+ dst_release_immediate(&nrt6->dst);
+ }
+out_unlock:
+ rcu_read_unlock();
+ }
+}
+
+static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
+ struct sk_buff *skb, u32 mtu,
+ bool confirm_neigh)
+{
+ __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu,
+ confirm_neigh);
+}
+
+void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
+ int oif, u32 mark, kuid_t uid)
+{
+ const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
+ struct dst_entry *dst;
+ 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), 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;
+
+ 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->sk_uid);
+
+ dst = __sk_dst_get(sk);
+ if (!dst || !dst->obsolete ||
+ dst->ops->check(dst, inet6_sk(sk)->dst_cookie))
+ return;
+
+ bh_lock_sock(sk);
+ if (!sock_owned_by_user(sk) && !ipv6_addr_v4mapped(&sk->sk_v6_daddr))
+ ip6_datagram_dst_update(sk, false);
+ bh_unlock_sock(sk);
+}
+EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
+
+void ip6_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) ?
+ &sk->sk_v6_daddr : NULL,
+#ifdef CONFIG_IPV6_SUBTREES
+ ipv6_addr_equal(&fl6->saddr, &np->saddr) ?
+ &np->saddr :
+#endif
+ NULL);
+}
+
+static bool ip6_redirect_nh_match(const struct fib6_result *res,
+ struct flowi6 *fl6,
+ const struct in6_addr *gw,
+ struct rt6_info **ret)
+{
+ const struct fib6_nh *nh = res->nh;
+
+ if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
+ fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
+ return false;
+
+ /* rt_cache's gateway might be different from its 'parent'
+ * in the case of an ip redirect.
+ * So we keep searching in the exception table if the gateway
+ * is different.
+ */
+ if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
+ struct rt6_info *rt_cache;
+
+ rt_cache = rt6_find_cached_rt(res, &fl6->daddr, &fl6->saddr);
+ if (rt_cache &&
+ ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
+ *ret = rt_cache;
+ return true;
+ }
+ return false;
+ }
+ return true;
+}
+
+struct fib6_nh_rd_arg {
+ struct fib6_result *res;
+ struct flowi6 *fl6;
+ const struct in6_addr *gw;
+ struct rt6_info **ret;
+};
+
+static int fib6_nh_redirect_match(struct fib6_nh *nh, void *_arg)
+{
+ struct fib6_nh_rd_arg *arg = _arg;
+
+ arg->res->nh = nh;
+ return ip6_redirect_nh_match(arg->res, arg->fl6, arg->gw, arg->ret);
+}
+
+/* Handle redirects */
+struct ip6rd_flowi {
+ struct flowi6 fl6;
+ struct in6_addr gateway;
+};
+
+INDIRECT_CALLABLE_SCOPE struct rt6_info *__ip6_route_redirect(struct net *net,
+ struct fib6_table *table,
+ struct flowi6 *fl6,
+ const struct sk_buff *skb,
+ int flags)
+{
+ struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
+ struct rt6_info *ret = NULL;
+ struct fib6_result res = {};
+ struct fib6_nh_rd_arg arg = {
+ .res = &res,
+ .fl6 = fl6,
+ .gw = &rdfl->gateway,
+ .ret = &ret
+ };
+ struct fib6_info *rt;
+ struct fib6_node *fn;
+
+ /* Get the "current" route for this destination and
+ * check if the redirect has come from appropriate router.
+ *
+ * RFC 4861 specifies that redirects should only be
+ * accepted if they come from the nexthop to the target.
+ * Due to the way the routes are chosen, this notion
+ * is a bit fuzzy and one might need to check all possible
+ * routes.
+ */
+
+ rcu_read_lock();
+ fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
+restart:
+ for_each_fib6_node_rt_rcu(fn) {
+ res.f6i = rt;
+ if (fib6_check_expired(rt))
+ continue;
+ if (rt->fib6_flags & RTF_REJECT)
+ break;
+ if (unlikely(rt->nh)) {
+ if (nexthop_is_blackhole(rt->nh))
+ continue;
+ /* on match, res->nh is filled in and potentially ret */
+ if (nexthop_for_each_fib6_nh(rt->nh,
+ fib6_nh_redirect_match,
+ &arg))
+ goto out;
+ } else {
+ res.nh = rt->fib6_nh;
+ if (ip6_redirect_nh_match(&res, fl6, &rdfl->gateway,
+ &ret))
+ goto out;
+ }
+ }
+
+ if (!rt)
+ rt = net->ipv6.fib6_null_entry;
+ else if (rt->fib6_flags & RTF_REJECT) {
+ ret = net->ipv6.ip6_null_entry;
+ goto out;
+ }
+
+ if (rt == net->ipv6.fib6_null_entry) {
+ fn = fib6_backtrack(fn, &fl6->saddr);
+ if (fn)
+ goto restart;
+ }
+
+ res.f6i = rt;
+ res.nh = rt->fib6_nh;
+out:
+ if (ret) {
+ ip6_hold_safe(net, &ret);
+ } else {
+ res.fib6_flags = res.f6i->fib6_flags;
+ res.fib6_type = res.f6i->fib6_type;
+ ret = ip6_create_rt_rcu(&res);
+ }
+
+ rcu_read_unlock();
+
+ trace_fib6_table_lookup(net, &res, table, fl6);
+ return ret;
+};
+
+static struct dst_entry *ip6_route_redirect(struct net *net,
+ const struct flowi6 *fl6,
+ const struct sk_buff *skb,
+ const struct in6_addr *gateway)
+{
+ int flags = RT6_LOOKUP_F_HAS_SADDR;
+ struct ip6rd_flowi rdfl;
+
+ rdfl.fl6 = *fl6;
+ rdfl.gateway = *gateway;
+
+ return fib6_rule_lookup(net, &rdfl.fl6, skb,
+ flags, __ip6_route_redirect);
+}
+
+void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark,
+ kuid_t uid)
+{
+ const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
+ struct dst_entry *dst;
+ struct flowi6 fl6 = {
+ .flowi6_iif = LOOPBACK_IFINDEX,
+ .flowi6_oif = oif,
+ .flowi6_mark = mark,
+ .daddr = iph->daddr,
+ .saddr = iph->saddr,
+ .flowlabel = ip6_flowinfo(iph),
+ .flowi6_uid = uid,
+ };
+
+ dst = ip6_route_redirect(net, &fl6, skb, &ipv6_hdr(skb)->saddr);
+ rt6_do_redirect(dst, NULL, skb);
+ dst_release(dst);
+}
+EXPORT_SYMBOL_GPL(ip6_redirect);
+
+void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif)
+{
+ const struct ipv6hdr *iph = ipv6_hdr(skb);
+ const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
+ struct dst_entry *dst;
+ struct flowi6 fl6 = {
+ .flowi6_iif = LOOPBACK_IFINDEX,
+ .flowi6_oif = oif,
+ .daddr = msg->dest,
+ .saddr = iph->daddr,
+ .flowi6_uid = sock_net_uid(net, NULL),
+ };
+
+ dst = ip6_route_redirect(net, &fl6, skb, &iph->saddr);
+ rt6_do_redirect(dst, NULL, skb);
+ dst_release(dst);
+}
+
+void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
+{
+ ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if,
+ READ_ONCE(sk->sk_mark), sk->sk_uid);
+}
+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);
+
+ mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
+
+ if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
+ mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
+
+ /*
+ * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
+ * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
+ * IPV6_MAXPLEN is also valid and means: "any MSS,
+ * rely only on pmtu discovery"
+ */
+ if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
+ mtu = IPV6_MAXPLEN;
+ return mtu;
+}
+
+INDIRECT_CALLABLE_SCOPE unsigned int ip6_mtu(const struct dst_entry *dst)
+{
+ return ip6_dst_mtu_maybe_forward(dst, false);
+}
+EXPORT_INDIRECT_CALLABLE(ip6_mtu);
+
+/* MTU selection:
+ * 1. mtu on route is locked - use it
+ * 2. mtu from nexthop exception
+ * 3. mtu from egress device
+ *
+ * based on ip6_dst_mtu_forward and exception logic of
+ * rt6_find_cached_rt; called with rcu_read_lock
+ */
+u32 ip6_mtu_from_fib6(const struct fib6_result *res,
+ const struct in6_addr *daddr,
+ const struct in6_addr *saddr)
+{
+ const struct fib6_nh *nh = res->nh;
+ struct fib6_info *f6i = res->f6i;
+ struct inet6_dev *idev;
+ struct rt6_info *rt;
+ u32 mtu = 0;
+
+ if (unlikely(fib6_metric_locked(f6i, RTAX_MTU))) {
+ mtu = f6i->fib6_pmtu;
+ if (mtu)
+ goto out;
+ }
+
+ 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;
+
+ mtu = IPV6_MIN_MTU;
+ idev = __in6_dev_get(dev);
+ if (idev && idev->cnf.mtu6 > mtu)
+ mtu = idev->cnf.mtu6;
+ }
+
+ mtu = min_t(unsigned int, mtu, IP6_MAX_MTU);
+out:
+ return mtu - lwtunnel_headroom(nh->fib_nh_lws, mtu);
+}
+
+struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
+ struct flowi6 *fl6)
+{
+ struct dst_entry *dst;
+ struct rt6_info *rt;
+ struct inet6_dev *idev = in6_dev_get(dev);
+ struct net *net = dev_net(dev);
+
+ if (unlikely(!idev))
+ return ERR_PTR(-ENODEV);
+
+ rt = ip6_dst_alloc(net, dev, 0);
+ if (unlikely(!rt)) {
+ in6_dev_put(idev);
+ dst = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ rt->dst.input = ip6_input;
+ rt->dst.output = ip6_output;
+ rt->rt6i_gateway = fl6->daddr;
+ rt->rt6i_dst.addr = fl6->daddr;
+ rt->rt6i_dst.plen = 128;
+ rt->rt6i_idev = idev;
+ dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
+
+ /* Add this dst into uncached_list so that rt6_disable_ip() can
+ * do proper release of the net_device
+ */
+ rt6_uncached_list_add(rt);
+
+ dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
+
+out:
+ return dst;
+}
+
+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_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 (entries > ops->gc_thresh)
+ entries = dst_entries_get_slow(ops);
+
+ if (time_after(rt_last_gc + rt_min_interval, jiffies))
+ goto out;
+
+ fib6_run_gc(atomic_inc_return(&net->ipv6.ip6_rt_gc_expire), net, true);
+ entries = dst_entries_get_slow(ops);
+ if (entries < ops->gc_thresh)
+ atomic_set(&net->ipv6.ip6_rt_gc_expire, rt_gc_timeout >> 1);
+out:
+ val = atomic_read(&net->ipv6.ip6_rt_gc_expire);
+ atomic_set(&net->ipv6.ip6_rt_gc_expire, val - (val >> rt_elasticity));
+}
+
+static int ip6_nh_lookup_table(struct net *net, struct fib6_config *cfg,
+ const struct in6_addr *gw_addr, u32 tbid,
+ int flags, struct fib6_result *res)
+{
+ struct flowi6 fl6 = {
+ .flowi6_oif = cfg->fc_ifindex,
+ .daddr = *gw_addr,
+ .saddr = cfg->fc_prefsrc,
+ };
+ struct fib6_table *table;
+ int err;
+
+ table = fib6_get_table(net, tbid);
+ if (!table)
+ return -EINVAL;
+
+ if (!ipv6_addr_any(&cfg->fc_prefsrc))
+ flags |= RT6_LOOKUP_F_HAS_SADDR;
+
+ flags |= RT6_LOOKUP_F_IGNORE_LINKSTATE;
+
+ err = fib6_table_lookup(net, table, cfg->fc_ifindex, &fl6, res, flags);
+ if (!err && res->f6i != net->ipv6.fib6_null_entry)
+ fib6_select_path(net, res, &fl6, cfg->fc_ifindex,
+ cfg->fc_ifindex != 0, NULL, flags);
+
+ return 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;
+
+ 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;
+ }
+
+ return err;
+}
+
+static int ip6_route_check_nh(struct net *net,
+ struct fib6_config *cfg,
+ struct net_device **_dev,
+ 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;
+ }
+
+ 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;
+ dev_hold(dev);
+ *idev = in6_dev_get(dev);
+ }
+
+ return err;
+}
+
+static int ip6_validate_gw(struct net *net, struct fib6_config *cfg,
+ struct net_device **_dev, struct inet6_dev **idev,
+ struct netlink_ext_ack *extack)
+{
+ const struct in6_addr *gw_addr = &cfg->fc_gateway;
+ int gwa_type = ipv6_addr_type(gw_addr);
+ bool skip_dev = gwa_type & IPV6_ADDR_LINKLOCAL ? false : true;
+ const struct net_device *dev = *_dev;
+ bool need_addr_check = !dev;
+ int err = -EINVAL;
+
+ /* if gw_addr is local we will fail to detect this in case
+ * address is still TENTATIVE (DAD in progress). rt6_lookup()
+ * will return already-added prefix route via interface that
+ * prefix route was assigned to, which might be non-loopback.
+ */
+ if (dev &&
+ ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
+ NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
+ goto out;
+ }
+
+ if (gwa_type != (IPV6_ADDR_LINKLOCAL | IPV6_ADDR_UNICAST)) {
+ /* IPv6 strictly inhibits using not link-local
+ * addresses as nexthop address.
+ * Otherwise, router will not able to send redirects.
+ * It is very good, but in some (rare!) circumstances
+ * (SIT, PtP, NBMA NOARP links) it is handy to allow
+ * some exceptions. --ANK
+ * We allow IPv4-mapped nexthops to support RFC4798-type
+ * addressing
+ */
+ if (!(gwa_type & (IPV6_ADDR_UNICAST | IPV6_ADDR_MAPPED))) {
+ NL_SET_ERR_MSG(extack, "Invalid gateway address");
+ goto out;
+ }
+
+ rcu_read_lock();
+
+ 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, idev);
+
+ rcu_read_unlock();
+
+ if (err)
+ goto out;
+ }
+
+ /* reload in case device was changed */
+ dev = *_dev;
+
+ err = -EINVAL;
+ if (!dev) {
+ NL_SET_ERR_MSG(extack, "Egress device not specified");
+ goto out;
+ } else if (dev->flags & IFF_LOOPBACK) {
+ NL_SET_ERR_MSG(extack,
+ "Egress device can not be loopback device for this route");
+ goto out;
+ }
+
+ /* if we did not check gw_addr above, do so now that the
+ * egress device has been resolved.
+ */
+ if (need_addr_check &&
+ ipv6_chk_addr_and_flags(net, gw_addr, dev, skip_dev, 0, 0)) {
+ NL_SET_ERR_MSG(extack, "Gateway can not be a local address");
+ goto out;
+ }
+
+ err = 0;
+out:
+ return err;
+}
+
+static bool fib6_is_reject(u32 flags, struct net_device *dev, int addr_type)
+{
+ if ((flags & RTF_REJECT) ||
+ (dev && (dev->flags & IFF_LOOPBACK) &&
+ !(addr_type & IPV6_ADDR_LOOPBACK) &&
+ !(flags & (RTF_ANYCAST | RTF_LOCAL))))
+ return true;
+
+ return false;
+}
+
+int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
+ struct fib6_config *cfg, gfp_t gfp_flags,
+ struct netlink_ext_ack *extack)
+{
+ struct net_device *dev = NULL;
+ struct inet6_dev *idev = NULL;
+ int addr_type;
+ 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 = dev_get_by_index(net, cfg->fc_ifindex);
+ 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) {
+ 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;
+ }
+ }
+ goto pcpu_alloc;
+ }
+
+ if (cfg->fc_flags & RTF_GATEWAY) {
+ err = ip6_validate_gw(net, cfg, &dev, &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->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;
+ netdev_tracker_alloc(dev, &fib6_nh->fib_nh_dev_tracker, gfp_flags);
+
+ fib6_nh->fib_nh_oif = dev->ifindex;
+ err = 0;
+out:
+ if (idev)
+ in6_dev_put(idev);
+
+ if (err) {
+ lwtstate_put(fib6_nh->fib_nh_lws);
+ fib6_nh->fib_nh_lws = NULL;
+ dev_put(dev);
+ }
+
+ 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 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_info *rt = NULL;
+ struct nexthop *nh = NULL;
+ struct fib6_table *table;
+ struct fib6_nh *fib6_nh;
+ int err = -EINVAL;
+ int addr_type;
+
+ /* 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;
+ }
+
+ /* 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 out;
+ }
+
+ if (cfg->fc_type > RTN_MAX) {
+ NL_SET_ERR_MSG(extack, "Invalid route type");
+ goto out;
+ }
+
+ if (cfg->fc_dst_len > 128) {
+ NL_SET_ERR_MSG(extack, "Invalid prefix length");
+ goto out;
+ }
+ if (cfg->fc_src_len > 128) {
+ NL_SET_ERR_MSG(extack, "Invalid source address length");
+ goto out;
+ }
+#ifndef CONFIG_IPV6_SUBTREES
+ if (cfg->fc_src_len) {
+ NL_SET_ERR_MSG(extack,
+ "Specifying source address requires IPV6_SUBTREES to be enabled");
+ goto out;
+ }
+#endif
+ if (cfg->fc_nh_id) {
+ nh = nexthop_find_by_id(net, cfg->fc_nh_id);
+ if (!nh) {
+ NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
+ goto out;
+ }
+ err = fib6_check_nexthop(nh, cfg, extack);
+ if (err)
+ goto out;
+ }
+
+ err = -ENOBUFS;
+ if (cfg->fc_nlinfo.nlh &&
+ !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
+ table = fib6_get_table(net, cfg->fc_table);
+ if (!table) {
+ pr_warn("NLM_F_CREATE should be specified when creating new route\n");
+ table = fib6_new_table(net, cfg->fc_table);
+ }
+ } else {
+ table = fib6_new_table(net, cfg->fc_table);
+ }
+
+ if (!table)
+ goto out;
+
+ err = -ENOMEM;
+ rt = fib6_info_alloc(gfp_flags, !nh);
+ if (!rt)
+ goto out;
+
+ rt->fib6_metrics = ip_fib_metrics_init(net, cfg->fc_mx, cfg->fc_mx_len,
+ extack);
+ if (IS_ERR(rt->fib6_metrics)) {
+ err = PTR_ERR(rt->fib6_metrics);
+ /* Do not leave garbage there. */
+ rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
+ goto out_free;
+ }
+
+ if (cfg->fc_flags & RTF_ADDRCONF)
+ rt->dst_nocount = true;
+
+ if (cfg->fc_flags & RTF_EXPIRES)
+ fib6_set_expires(rt, jiffies +
+ clock_t_to_jiffies(cfg->fc_expires));
+ else
+ fib6_clean_expires(rt);
+
+ if (cfg->fc_protocol == RTPROT_UNSPEC)
+ cfg->fc_protocol = RTPROT_BOOT;
+ 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;
+
+ 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->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
+ rt->fib6_src.plen = cfg->fc_src_len;
+#endif
+ if (nh) {
+ if (rt->fib6_src.plen) {
+ NL_SET_ERR_MSG(extack, "Nexthops can not be used with source routing");
+ goto out_free;
+ }
+ if (!nexthop_get(nh)) {
+ NL_SET_ERR_MSG(extack, "Nexthop has been deleted");
+ goto out_free;
+ }
+ rt->nh = nh;
+ fib6_nh = nexthop_fib6_nh(rt->nh);
+ } else {
+ err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
+ if (err)
+ goto out;
+
+ fib6_nh = rt->fib6_nh;
+
+ /* We cannot add true routes via loopback here, they would
+ * result in kernel looping; promote them to reject routes
+ */
+ addr_type = ipv6_addr_type(&cfg->fc_dst);
+ if (fib6_is_reject(cfg->fc_flags, rt->fib6_nh->fib_nh_dev,
+ addr_type))
+ rt->fib6_flags = RTF_REJECT | RTF_NONEXTHOP;
+ }
+
+ if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
+ struct net_device *dev = fib6_nh->fib_nh_dev;
+
+ if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
+ NL_SET_ERR_MSG(extack, "Invalid source address");
+ err = -EINVAL;
+ goto out;
+ }
+ rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
+ rt->fib6_prefsrc.plen = 128;
+ } else
+ rt->fib6_prefsrc.plen = 0;
+
+ return rt;
+out:
+ fib6_info_release(rt);
+ return ERR_PTR(err);
+out_free:
+ ip_fib_metrics_put(rt->fib6_metrics);
+ kfree(rt);
+ return ERR_PTR(err);
+}
+
+int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_info *rt;
+ int err;
+
+ rt = ip6_route_info_create(cfg, gfp_flags, extack);
+ if (IS_ERR(rt))
+ return PTR_ERR(rt);
+
+ err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
+ fib6_info_release(rt);
+
+ return err;
+}
+
+static int __ip6_del_rt(struct fib6_info *rt, struct nl_info *info)
+{
+ struct net *net = info->nl_net;
+ struct fib6_table *table;
+ int err;
+
+ if (rt == net->ipv6.fib6_null_entry) {
+ err = -ENOENT;
+ goto out;
+ }
+
+ table = rt->fib6_table;
+ spin_lock_bh(&table->tb6_lock);
+ err = fib6_del(rt, info);
+ spin_unlock_bh(&table->tb6_lock);
+
+out:
+ fib6_info_release(rt);
+ return err;
+}
+
+int ip6_del_rt(struct net *net, struct fib6_info *rt, bool skip_notify)
+{
+ struct nl_info info = {
+ .nl_net = net,
+ .skip_notify = skip_notify
+ };
+
+ return __ip6_del_rt(rt, &info);
+}
+
+static int __ip6_del_rt_siblings(struct fib6_info *rt, struct fib6_config *cfg)
+{
+ struct nl_info *info = &cfg->fc_nlinfo;
+ struct net *net = info->nl_net;
+ struct sk_buff *skb = NULL;
+ struct fib6_table *table;
+ int err = -ENOENT;
+
+ if (rt == net->ipv6.fib6_null_entry)
+ goto out_put;
+ table = rt->fib6_table;
+ spin_lock_bh(&table->tb6_lock);
+
+ if (rt->fib6_nsiblings && cfg->fc_delete_all_nh) {
+ struct fib6_info *sibling, *next_sibling;
+ struct fib6_node *fn;
+
+ /* prefer to send a single notification with all hops */
+ skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
+ if (skb) {
+ u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
+
+ if (rt6_fill_node(net, skb, rt, NULL,
+ NULL, NULL, 0, RTM_DELROUTE,
+ info->portid, seq, 0) < 0) {
+ kfree_skb(skb);
+ skb = NULL;
+ } else
+ info->skip_notify = 1;
+ }
+
+ /* 'rt' points to the first sibling route. If it is not the
+ * leaf, then we do not need to send a notification. Otherwise,
+ * we need to check if the last sibling has a next route or not
+ * and emit a replace or delete notification, respectively.
+ */
+ info->skip_notify_kernel = 1;
+ fn = rcu_dereference_protected(rt->fib6_node,
+ lockdep_is_held(&table->tb6_lock));
+ if (rcu_access_pointer(fn->leaf) == rt) {
+ struct fib6_info *last_sibling, *replace_rt;
+
+ last_sibling = list_last_entry(&rt->fib6_siblings,
+ struct fib6_info,
+ fib6_siblings);
+ replace_rt = rcu_dereference_protected(
+ last_sibling->fib6_next,
+ lockdep_is_held(&table->tb6_lock));
+ if (replace_rt)
+ call_fib6_entry_notifiers_replace(net,
+ replace_rt);
+ else
+ call_fib6_multipath_entry_notifiers(net,
+ FIB_EVENT_ENTRY_DEL,
+ rt, rt->fib6_nsiblings,
+ NULL);
+ }
+ list_for_each_entry_safe(sibling, next_sibling,
+ &rt->fib6_siblings,
+ fib6_siblings) {
+ err = fib6_del(sibling, info);
+ if (err)
+ goto out_unlock;
+ }
+ }
+
+ err = fib6_del(rt, info);
+out_unlock:
+ spin_unlock_bh(&table->tb6_lock);
+out_put:
+ fib6_info_release(rt);
+
+ if (skb) {
+ rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
+ info->nlh, gfp_any());
+ }
+ return err;
+}
+
+static int __ip6_del_cached_rt(struct rt6_info *rt, struct fib6_config *cfg)
+{
+ int rc = -ESRCH;
+
+ if (cfg->fc_ifindex && rt->dst.dev->ifindex != cfg->fc_ifindex)
+ goto out;
+
+ if (cfg->fc_flags & RTF_GATEWAY &&
+ !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
+ goto out;
+
+ rc = rt6_remove_exception_rt(rt);
+out:
+ return rc;
+}
+
+static int ip6_del_cached_rt(struct fib6_config *cfg, struct fib6_info *rt,
+ struct fib6_nh *nh)
+{
+ struct fib6_result res = {
+ .f6i = rt,
+ .nh = nh,
+ };
+ struct rt6_info *rt_cache;
+
+ rt_cache = rt6_find_cached_rt(&res, &cfg->fc_dst, &cfg->fc_src);
+ if (rt_cache)
+ return __ip6_del_cached_rt(rt_cache, cfg);
+
+ return 0;
+}
+
+struct fib6_nh_del_cached_rt_arg {
+ struct fib6_config *cfg;
+ struct fib6_info *f6i;
+};
+
+static int fib6_nh_del_cached_rt(struct fib6_nh *nh, void *_arg)
+{
+ struct fib6_nh_del_cached_rt_arg *arg = _arg;
+ int rc;
+
+ rc = ip6_del_cached_rt(arg->cfg, arg->f6i, nh);
+ return rc != -ESRCH ? rc : 0;
+}
+
+static int ip6_del_cached_rt_nh(struct fib6_config *cfg, struct fib6_info *f6i)
+{
+ struct fib6_nh_del_cached_rt_arg arg = {
+ .cfg = cfg,
+ .f6i = f6i
+ };
+
+ return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_del_cached_rt, &arg);
+}
+
+static int ip6_route_del(struct fib6_config *cfg,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_table *table;
+ struct fib6_info *rt;
+ struct fib6_node *fn;
+ int err = -ESRCH;
+
+ table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
+ if (!table) {
+ NL_SET_ERR_MSG(extack, "FIB table does not exist");
+ return err;
+ }
+
+ 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_flags & RTF_CACHE));
+
+ if (fn) {
+ 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;
+ rcu_read_unlock();
+
+ return __ip6_del_rt(rt, &cfg->fc_nlinfo);
+ }
+ if (cfg->fc_nh_id)
+ continue;
+
+ nh = rt->fib6_nh;
+ if (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, &nh->fib_nh_gw6))
+ continue;
+ if (!fib6_info_hold_safe(rt))
+ continue;
+ rcu_read_unlock();
+
+ /* 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);
+ }
+ }
+ rcu_read_unlock();
+
+ return err;
+}
+
+static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
+{
+ 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;
+ struct rd_msg *msg;
+ int optlen, on_link;
+ u8 *lladdr;
+
+ optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
+ optlen -= sizeof(*msg);
+
+ if (optlen < 0) {
+ net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
+ return;
+ }
+
+ msg = (struct rd_msg *)icmp6_hdr(skb);
+
+ if (ipv6_addr_is_multicast(&msg->dest)) {
+ net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
+ return;
+ }
+
+ on_link = 0;
+ if (ipv6_addr_equal(&msg->dest, &msg->target)) {
+ on_link = 1;
+ } else if (ipv6_addr_type(&msg->target) !=
+ (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
+ net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
+ return;
+ }
+
+ in6_dev = __in6_dev_get(skb->dev);
+ if (!in6_dev)
+ return;
+ if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
+ return;
+
+ /* RFC2461 8.1:
+ * The IP source address of the Redirect MUST be the same as the current
+ * first-hop router for the specified ICMP Destination Address.
+ */
+
+ if (!ndisc_parse_options(skb->dev, msg->opt, optlen, &ndopts)) {
+ net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
+ return;
+ }
+
+ lladdr = NULL;
+ if (ndopts.nd_opts_tgt_lladdr) {
+ lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
+ skb->dev);
+ if (!lladdr) {
+ net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
+ return;
+ }
+ }
+
+ rt = (struct 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;
+ }
+
+ /* Redirect received -> path was valid.
+ * Look, redirects are sent only in response to data packets,
+ * so that this nexthop apparently is reachable. --ANK
+ */
+ dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
+
+ neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
+ if (!neigh)
+ return;
+
+ /*
+ * We have finally decided to accept it.
+ */
+
+ ndisc_update(skb->dev, neigh, lladdr, NUD_STALE,
+ NEIGH_UPDATE_F_WEAK_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE|
+ (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
+ NEIGH_UPDATE_F_ISROUTER)),
+ NDISC_REDIRECT, &ndopts);
+
+ rcu_read_lock();
+ res.f6i = rcu_dereference(rt->from);
+ if (!res.f6i)
+ goto out;
+
+ if (res.f6i->nh) {
+ struct fib6_nh_match_arg arg = {
+ .dev = dst->dev,
+ .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;
+
+ nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
+ if (on_link)
+ nrt->rt6i_flags &= ~RTF_GATEWAY;
+
+ nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
+
+ /* 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;
+ netevent.daddr = &msg->dest;
+ netevent.neigh = neigh;
+ call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
+
+out:
+ rcu_read_unlock();
+ neigh_release(neigh);
+}
+
+#ifdef CONFIG_IPV6_ROUTE_INFO
+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)
+{
+ u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
+ int ifindex = dev->ifindex;
+ struct fib6_node *fn;
+ struct fib6_info *rt = NULL;
+ struct fib6_table *table;
+
+ table = fib6_get_table(net, tb_id);
+ if (!table)
+ return NULL;
+
+ rcu_read_lock();
+ fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0, true);
+ if (!fn)
+ goto out;
+
+ for_each_fib6_node_rt_rcu(fn) {
+ /* these routes do not use nexthops */
+ if (rt->nh)
+ continue;
+ if (rt->fib6_nh->fib_nh_dev->ifindex != ifindex)
+ continue;
+ 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;
+ break;
+ }
+out:
+ rcu_read_unlock();
+ return rt;
+}
+
+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)
+{
+ struct fib6_config cfg = {
+ .fc_metric = IP6_RT_PRIO_USER,
+ .fc_ifindex = dev->ifindex,
+ .fc_dst_len = prefixlen,
+ .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
+ RTF_UP | RTF_PREF(pref),
+ .fc_protocol = RTPROT_RA,
+ .fc_type = RTN_UNICAST,
+ .fc_nlinfo.portid = 0,
+ .fc_nlinfo.nlh = NULL,
+ .fc_nlinfo.nl_net = net,
+ };
+
+ cfg.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_INFO;
+ cfg.fc_dst = *prefix;
+ cfg.fc_gateway = *gwaddr;
+
+ /* We should treat it as a default route if prefix length is 0. */
+ if (!prefixlen)
+ cfg.fc_flags |= RTF_DEFAULT;
+
+ ip6_route_add(&cfg, GFP_ATOMIC, NULL);
+
+ return rt6_get_route_info(net, prefix, prefixlen, gwaddr, dev);
+}
+#endif
+
+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 fib6_info *rt;
+ struct fib6_table *table;
+
+ table = fib6_get_table(net, tb_id);
+ if (!table)
+ return NULL;
+
+ 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 && !fib6_info_hold_safe(rt))
+ rt = NULL;
+ rcu_read_unlock();
+ return rt;
+}
+
+struct fib6_info *rt6_add_dflt_router(struct net *net,
+ const struct in6_addr *gwaddr,
+ struct net_device *dev,
+ unsigned int pref,
+ u32 defrtr_usr_metric)
+{
+ struct fib6_config cfg = {
+ .fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
+ .fc_metric = defrtr_usr_metric,
+ .fc_ifindex = dev->ifindex,
+ .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
+ RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
+ .fc_protocol = RTPROT_RA,
+ .fc_type = RTN_UNICAST,
+ .fc_nlinfo.portid = 0,
+ .fc_nlinfo.nlh = NULL,
+ .fc_nlinfo.nl_net = net,
+ };
+
+ cfg.fc_gateway = *gwaddr;
+
+ if (!ip6_route_add(&cfg, GFP_ATOMIC, NULL)) {
+ struct fib6_table *table;
+
+ table = fib6_get_table(dev_net(dev), cfg.fc_table);
+ if (table)
+ table->flags |= RT6_TABLE_HAS_DFLT_ROUTER;
+ }
+
+ return rt6_get_dflt_router(net, gwaddr, dev);
+}
+
+static void __rt6_purge_dflt_routers(struct net *net,
+ struct fib6_table *table)
+{
+ struct fib6_info *rt;
+
+restart:
+ rcu_read_lock();
+ for_each_fib6_node_rt_rcu(&table->tb6_root) {
+ struct net_device *dev = fib6_info_nh_dev(rt);
+ struct inet6_dev *idev = dev ? __in6_dev_get(dev) : NULL;
+
+ if (rt->fib6_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
+ (!idev || idev->cnf.accept_ra != 2) &&
+ fib6_info_hold_safe(rt)) {
+ rcu_read_unlock();
+ ip6_del_rt(net, rt, false);
+ goto restart;
+ }
+ }
+ rcu_read_unlock();
+
+ table->flags &= ~RT6_TABLE_HAS_DFLT_ROUTER;
+}
+
+void rt6_purge_dflt_routers(struct net *net)
+{
+ struct fib6_table *table;
+ struct hlist_head *head;
+ unsigned int h;
+
+ rcu_read_lock();
+
+ for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
+ head = &net->ipv6.fib_table_hash[h];
+ hlist_for_each_entry_rcu(table, head, tb6_hlist) {
+ if (table->flags & RT6_TABLE_HAS_DFLT_ROUTER)
+ __rt6_purge_dflt_routers(net, table);
+ }
+ }
+
+ rcu_read_unlock();
+}
+
+static void rtmsg_to_fib6_config(struct net *net,
+ struct in6_rtmsg *rtmsg,
+ struct fib6_config *cfg)
+{
+ *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 ? : IP6_RT_PRIO_USER,
+ .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,
+
+ .fc_nlinfo.nl_net = net,
+
+ .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, struct in6_rtmsg *rtmsg)
+{
+ struct fib6_config cfg;
+ int err;
+
+ if (cmd != SIOCADDRT && cmd != SIOCDELRT)
+ return -EINVAL;
+ if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+ return -EPERM;
+
+ rtmsg_to_fib6_config(net, rtmsg, &cfg);
+
+ rtnl_lock();
+ switch (cmd) {
+ case SIOCADDRT:
+ err = ip6_route_add(&cfg, GFP_KERNEL, NULL);
+ break;
+ case SIOCDELRT:
+ err = ip6_route_del(&cfg, NULL);
+ break;
+ }
+ rtnl_unlock();
+ return err;
+}
+
+/*
+ * Drop the packet on the floor
+ */
+
+static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct net *net = dev_net(dst->dev);
+ struct inet6_dev *idev;
+ SKB_DR(reason);
+ int type;
+
+ if (netif_is_l3_master(skb->dev) ||
+ dst->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) {
+ SKB_DR_SET(reason, IP_INADDRERRORS);
+ IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
+ break;
+ }
+ SKB_DR_SET(reason, IP_INNOROUTES);
+ fallthrough;
+ case IPSTATS_MIB_OUTNOROUTES:
+ 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_reason(skb, reason);
+ return 0;
+}
+
+static int ip6_pkt_discard(struct sk_buff *skb)
+{
+ return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
+}
+
+static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ skb->dev = skb_dst(skb)->dev;
+ return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
+}
+
+static int ip6_pkt_prohibit(struct sk_buff *skb)
+{
+ return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
+}
+
+static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ skb->dev = skb_dst(skb)->dev;
+ return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
+}
+
+/*
+ * Allocate a dst for local (unicast / anycast) address.
+ */
+
+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 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;
+
+ if (anycast) {
+ cfg.fc_type = RTN_ANYCAST;
+ cfg.fc_flags |= RTF_ANYCAST;
+ } else {
+ cfg.fc_type = RTN_LOCAL;
+ cfg.fc_flags |= RTF_LOCAL;
+ }
+
+ f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
+ if (!IS_ERR(f6i)) {
+ f6i->dst_nocount = true;
+
+ if (!anycast &&
+ (net->ipv6.devconf_all->disable_policy ||
+ idev->cnf.disable_policy))
+ f6i->dst_nopolicy = true;
+ }
+
+ 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 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 (!rt->nh &&
+ ((void *)rt->fib6_nh->fib_nh_dev == dev || !dev) &&
+ rt != net->ipv6.fib6_null_entry &&
+ ipv6_addr_equal(addr, &rt->fib6_prefsrc.addr)) {
+ spin_lock_bh(&rt6_exception_lock);
+ /* remove prefsrc entry */
+ rt->fib6_prefsrc.plen = 0;
+ spin_unlock_bh(&rt6_exception_lock);
+ }
+ return 0;
+}
+
+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)
+
+/* Remove routers and update dst entries when gateway turn into host. */
+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;
+
+ nh = rt->fib6_nh;
+ if (((rt->fib6_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) &&
+ nh->fib_nh_gw_family && ipv6_addr_equal(gateway, &nh->fib_nh_gw6))
+ return -1;
+
+ /* Further clean up cached routes in exception table.
+ * This is needed because cached route may have a different
+ * gateway than its 'parent' in the case of an ip redirect.
+ */
+ fib6_nh_exceptions_clean_tohost(nh, gateway);
+
+ return 0;
+}
+
+void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
+{
+ fib6_clean_all(net, fib6_clean_tohost, gateway);
+}
+
+struct arg_netdev_event {
+ const struct net_device *dev;
+ union {
+ unsigned char nh_flags;
+ unsigned long event;
+ };
+};
+
+static struct fib6_info *rt6_multipath_first_sibling(const struct fib6_info *rt)
+{
+ struct fib6_info *iter;
+ struct fib6_node *fn;
+
+ fn = rcu_dereference_protected(rt->fib6_node,
+ lockdep_is_held(&rt->fib6_table->tb6_lock));
+ iter = rcu_dereference_protected(fn->leaf,
+ lockdep_is_held(&rt->fib6_table->tb6_lock));
+ while (iter) {
+ if (iter->fib6_metric == rt->fib6_metric &&
+ rt6_qualify_for_ecmp(iter))
+ return iter;
+ iter = rcu_dereference_protected(iter->fib6_next,
+ lockdep_is_held(&rt->fib6_table->tb6_lock));
+ }
+
+ return NULL;
+}
+
+/* only called for fib entries with builtin fib6_nh */
+static bool rt6_is_dead(const struct fib6_info *rt)
+{
+ if (rt->fib6_nh->fib_nh_flags & RTNH_F_DEAD ||
+ (rt->fib6_nh->fib_nh_flags & RTNH_F_LINKDOWN &&
+ ip6_ignore_linkdown(rt->fib6_nh->fib_nh_dev)))
+ return true;
+
+ return false;
+}
+
+static int rt6_multipath_total_weight(const struct fib6_info *rt)
+{
+ struct fib6_info *iter;
+ int total = 0;
+
+ if (!rt6_is_dead(rt))
+ total += rt->fib6_nh->fib_nh_weight;
+
+ list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
+ if (!rt6_is_dead(iter))
+ total += iter->fib6_nh->fib_nh_weight;
+ }
+
+ return total;
+}
+
+static void rt6_upper_bound_set(struct fib6_info *rt, int *weight, int total)
+{
+ int upper_bound = -1;
+
+ if (!rt6_is_dead(rt)) {
+ *weight += rt->fib6_nh->fib_nh_weight;
+ upper_bound = DIV_ROUND_CLOSEST_ULL((u64) (*weight) << 31,
+ total) - 1;
+ }
+ atomic_set(&rt->fib6_nh->fib_nh_upper_bound, upper_bound);
+}
+
+static void rt6_multipath_upper_bound_set(struct fib6_info *rt, int total)
+{
+ struct fib6_info *iter;
+ int weight = 0;
+
+ rt6_upper_bound_set(rt, &weight, total);
+
+ list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings)
+ rt6_upper_bound_set(iter, &weight, total);
+}
+
+void rt6_multipath_rebalance(struct fib6_info *rt)
+{
+ struct fib6_info *first;
+ int total;
+
+ /* In case the entire multipath route was marked for flushing,
+ * then there is no need to rebalance upon the removal of every
+ * sibling route.
+ */
+ if (!rt->fib6_nsiblings || rt->should_flush)
+ return;
+
+ /* During lookup routes are evaluated in order, so we need to
+ * make sure upper bounds are assigned from the first sibling
+ * onwards.
+ */
+ first = rt6_multipath_first_sibling(rt);
+ if (WARN_ON_ONCE(!first))
+ return;
+
+ total = rt6_multipath_total_weight(first);
+ rt6_multipath_upper_bound_set(first, total);
+}
+
+static int fib6_ifup(struct fib6_info *rt, void *p_arg)
+{
+ const struct arg_netdev_event *arg = p_arg;
+ struct net *net = dev_net(arg->dev);
+
+ if (rt != net->ipv6.fib6_null_entry && !rt->nh &&
+ rt->fib6_nh->fib_nh_dev == arg->dev) {
+ rt->fib6_nh->fib_nh_flags &= ~arg->nh_flags;
+ fib6_update_sernum_upto_root(net, rt);
+ rt6_multipath_rebalance(rt);
+ }
+
+ return 0;
+}
+
+void rt6_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 fib6_info *rt, void *p_arg)
+{
+ const struct arg_netdev_event *arg = p_arg;
+ const struct net_device *dev = arg->dev;
+ struct net *net = dev_net(dev);
+
+ if (rt == net->ipv6.fib6_null_entry || rt->nh)
+ return 0;
+
+ switch (arg->event) {
+ case NETDEV_UNREGISTER:
+ return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
+ case NETDEV_DOWN:
+ if (rt->should_flush)
+ return -1;
+ if (!rt->fib6_nsiblings)
+ return rt->fib6_nh->fib_nh_dev == dev ? -1 : 0;
+ if (rt6_multipath_uses_dev(rt, dev)) {
+ unsigned int count;
+
+ count = rt6_multipath_dead_count(rt, dev);
+ if (rt->fib6_nsiblings + 1 == count) {
+ rt6_multipath_flush(rt);
+ return -1;
+ }
+ rt6_multipath_nh_flags_set(rt, dev, RTNH_F_DEAD |
+ RTNH_F_LINKDOWN);
+ fib6_update_sernum(net, rt);
+ rt6_multipath_rebalance(rt);
+ }
+ return -2;
+ case NETDEV_CHANGE:
+ if (rt->fib6_nh->fib_nh_dev != dev ||
+ rt->fib6_flags & (RTF_LOCAL | RTF_ANYCAST))
+ break;
+ rt->fib6_nh->fib_nh_flags |= RTNH_F_LINKDOWN;
+ rt6_multipath_rebalance(rt);
+ break;
+ }
+
+ return 0;
+}
+
+void rt6_sync_down_dev(struct net_device *dev, unsigned long event)
+{
+ struct arg_netdev_event arg = {
+ .dev = dev,
+ {
+ .event = event,
+ },
+ };
+ struct net *net = dev_net(dev);
+
+ if (net->ipv6.sysctl.skip_notify_on_dev_down)
+ fib6_clean_all_skip_notify(net, fib6_ifdown, &arg);
+ else
+ fib6_clean_all(net, fib6_ifdown, &arg);
+}
+
+void rt6_disable_ip(struct net_device *dev, unsigned long event)
+{
+ rt6_sync_down_dev(dev, event);
+ rt6_uncached_list_flush_dev(dev);
+ neigh_ifdown(&nd_tbl, dev);
+}
+
+struct rt6_mtu_change_arg {
+ struct net_device *dev;
+ unsigned int mtu;
+ struct fib6_info *f6i;
+};
+
+static int 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;
+
+ /* In IPv6 pmtu discovery is not optional,
+ so that RTAX_MTU lock cannot disable it.
+ We still use this lock to block changes
+ caused by addrconf/ndisc.
+ */
+
+ idev = __in6_dev_get(arg->dev);
+ if (!idev)
+ return 0;
+
+ 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 fib6_nh_mtu_change(f6i->fib6_nh, arg);
+}
+
+void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
+{
+ struct rt6_mtu_change_arg arg = {
+ .dev = dev,
+ .mtu = mtu,
+ };
+
+ fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
+}
+
+static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
+ [RTA_UNSPEC] = { .strict_start_type = RTA_DPORT + 1 },
+ [RTA_GATEWAY] = { .len = sizeof(struct in6_addr) },
+ [RTA_PREFSRC] = { .len = sizeof(struct in6_addr) },
+ [RTA_OIF] = { .type = NLA_U32 },
+ [RTA_IIF] = { .type = NLA_U32 },
+ [RTA_PRIORITY] = { .type = NLA_U32 },
+ [RTA_METRICS] = { .type = NLA_NESTED },
+ [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
+ [RTA_PREF] = { .type = NLA_U8 },
+ [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
+ [RTA_ENCAP] = { .type = NLA_NESTED },
+ [RTA_EXPIRES] = { .type = NLA_U32 },
+ [RTA_UID] = { .type = NLA_U32 },
+ [RTA_MARK] = { .type = NLA_U32 },
+ [RTA_TABLE] = { .type = NLA_U32 },
+ [RTA_IP_PROTO] = { .type = NLA_U8 },
+ [RTA_SPORT] = { .type = NLA_U16 },
+ [RTA_DPORT] = { .type = NLA_U16 },
+ [RTA_NH_ID] = { .type = NLA_U32 },
+};
+
+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;
+ struct nlattr *tb[RTA_MAX+1];
+ unsigned int pref;
+ int err;
+
+ 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);
+
+ if (rtm->rtm_tos) {
+ NL_SET_ERR_MSG(extack,
+ "Invalid dsfield (tos): option not available for IPv6");
+ 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 ||
+ rtm->rtm_type == RTN_PROHIBIT ||
+ rtm->rtm_type == RTN_THROW)
+ cfg->fc_flags |= RTF_REJECT;
+
+ if (rtm->rtm_type == RTN_LOCAL)
+ cfg->fc_flags |= RTF_LOCAL;
+
+ if (rtm->rtm_flags & RTM_F_CLONED)
+ cfg->fc_flags |= RTF_CACHE;
+
+ cfg->fc_flags |= (rtm->rtm_flags & RTNH_F_ONLINK);
+
+ if (tb[RTA_NH_ID]) {
+ if (tb[RTA_GATEWAY] || tb[RTA_OIF] ||
+ tb[RTA_MULTIPATH] || tb[RTA_ENCAP]) {
+ NL_SET_ERR_MSG(extack,
+ "Nexthop specification and nexthop id are mutually exclusive");
+ goto errout;
+ }
+ cfg->fc_nh_id = nla_get_u32(tb[RTA_NH_ID]);
+ }
+
+ if (tb[RTA_GATEWAY]) {
+ 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;
+
+ if (nla_len(tb[RTA_DST]) < plen)
+ goto errout;
+
+ nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
+ }
+
+ if (tb[RTA_SRC]) {
+ int plen = (rtm->rtm_src_len + 7) >> 3;
+
+ if (nla_len(tb[RTA_SRC]) < plen)
+ goto errout;
+
+ nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
+ }
+
+ if (tb[RTA_PREFSRC])
+ cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
+
+ if (tb[RTA_OIF])
+ cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
+
+ if (tb[RTA_PRIORITY])
+ cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
+
+ if (tb[RTA_METRICS]) {
+ cfg->fc_mx = nla_data(tb[RTA_METRICS]);
+ cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
+ }
+
+ if (tb[RTA_TABLE])
+ cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
+
+ if (tb[RTA_MULTIPATH]) {
+ 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);
+ if (err < 0)
+ goto errout;
+ }
+
+ if (tb[RTA_PREF]) {
+ pref = nla_get_u8(tb[RTA_PREF]);
+ if (pref != ICMPV6_ROUTER_PREF_LOW &&
+ pref != ICMPV6_ROUTER_PREF_HIGH)
+ pref = ICMPV6_ROUTER_PREF_MEDIUM;
+ cfg->fc_flags |= RTF_PREF(pref);
+ }
+
+ if (tb[RTA_ENCAP])
+ cfg->fc_encap = tb[RTA_ENCAP];
+
+ if (tb[RTA_ENCAP_TYPE]) {
+ cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
+
+ err = lwtunnel_valid_encap_type(cfg->fc_encap_type, extack);
+ if (err < 0)
+ goto errout;
+ }
+
+ if (tb[RTA_EXPIRES]) {
+ unsigned long timeout = addrconf_timeout_fixup(nla_get_u32(tb[RTA_EXPIRES]), HZ);
+
+ if (addrconf_finite_timeout(timeout)) {
+ cfg->fc_expires = jiffies_to_clock_t(timeout * HZ);
+ cfg->fc_flags |= RTF_EXPIRES;
+ }
+ }
+
+ err = 0;
+errout:
+ return err;
+}
+
+struct rt6_nh {
+ struct fib6_info *fib6_info;
+ struct fib6_config r_cfg;
+ struct list_head next;
+};
+
+static int ip6_route_info_append(struct net *net,
+ struct list_head *rt6_nh_list,
+ 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 fib6_info already exists */
+ if (rt6_duplicate_nexthop(nh->fib6_info, rt))
+ return err;
+ }
+
+ nh = kzalloc(sizeof(*nh), GFP_KERNEL);
+ if (!nh)
+ return -ENOMEM;
+ nh->fib6_info = rt;
+ memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
+ list_add_tail(&nh->next, rt6_nh_list);
+
+ return 0;
+}
+
+static void ip6_route_mpath_notify(struct fib6_info *rt,
+ struct fib6_info *rt_last,
+ struct nl_info *info,
+ __u16 nlflags)
+{
+ /* if this is an APPEND route, then rt points to the first route
+ * inserted and rt_last points to last route inserted. Userspace
+ * wants a consistent dump of the route which starts at the first
+ * nexthop. Since sibling routes are always added at the end of
+ * the list, find the first sibling of the last route appended
+ */
+ if ((nlflags & NLM_F_APPEND) && rt_last && rt_last->fib6_nsiblings) {
+ rt = list_first_entry(&rt_last->fib6_siblings,
+ struct fib6_info,
+ fib6_siblings);
+ }
+
+ if (rt)
+ inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
+}
+
+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 fib6_gw_from_attr(struct in6_addr *gw, struct nlattr *nla,
+ struct netlink_ext_ack *extack)
+{
+ if (nla_len(nla) < sizeof(*gw)) {
+ NL_SET_ERR_MSG(extack, "Invalid IPv6 address in RTA_GATEWAY");
+ return -EINVAL;
+ }
+
+ *gw = nla_get_in6_addr(nla);
+
+ return 0;
+}
+
+static int ip6_route_multipath_add(struct fib6_config *cfg,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_info *rt_notif = NULL, *rt_last = NULL;
+ struct nl_info *info = &cfg->fc_nlinfo;
+ struct fib6_config r_cfg;
+ struct rtnexthop *rtnh;
+ struct fib6_info *rt;
+ struct rt6_nh *err_nh;
+ struct rt6_nh *nh, *nh_safe;
+ __u16 nlflags;
+ int remaining;
+ int attrlen;
+ int err = 1;
+ int nhn = 0;
+ int replace = (cfg->fc_nlinfo.nlh &&
+ (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
+ LIST_HEAD(rt6_nh_list);
+
+ nlflags = replace ? NLM_F_REPLACE : NLM_F_CREATE;
+ if (info->nlh && info->nlh->nlmsg_flags & NLM_F_APPEND)
+ nlflags |= NLM_F_APPEND;
+
+ remaining = cfg->fc_mp_len;
+ rtnh = (struct rtnexthop *)cfg->fc_mp;
+
+ /* Parse a Multipath Entry and build a list (rt6_nh_list) of
+ * fib6_info structs per nexthop
+ */
+ while (rtnh_ok(rtnh, remaining)) {
+ memcpy(&r_cfg, cfg, sizeof(*cfg));
+ if (rtnh->rtnh_ifindex)
+ r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
+
+ attrlen = rtnh_attrlen(rtnh);
+ if (attrlen > 0) {
+ struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
+
+ nla = nla_find(attrs, attrlen, RTA_GATEWAY);
+ if (nla) {
+ err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
+ extack);
+ if (err)
+ goto cleanup;
+
+ r_cfg.fc_flags |= RTF_GATEWAY;
+ }
+ r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
+
+ /* RTA_ENCAP_TYPE length checked in
+ * lwtunnel_valid_encap_type_attr
+ */
+ nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
+ if (nla)
+ r_cfg.fc_encap_type = nla_get_u16(nla);
+ }
+
+ 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;
+ }
+ if (!rt6_qualify_for_ecmp(rt)) {
+ err = -EINVAL;
+ NL_SET_ERR_MSG(extack,
+ "Device only routes can not be added for IPv6 using the multipath API.");
+ fib6_info_release(rt);
+ goto cleanup;
+ }
+
+ rt->fib6_nh->fib_nh_weight = rtnh->rtnh_hops + 1;
+
+ err = ip6_route_info_append(info->nl_net, &rt6_nh_list,
+ rt, &r_cfg);
+ if (err) {
+ fib6_info_release(rt);
+ goto cleanup;
+ }
+
+ rtnh = rtnh_next(rtnh, &remaining);
+ }
+
+ if (list_empty(&rt6_nh_list)) {
+ NL_SET_ERR_MSG(extack,
+ "Invalid nexthop configuration - no valid nexthops");
+ return -EINVAL;
+ }
+
+ /* for add and replace send one notification with all nexthops.
+ * Skip the notification in fib6_add_rt2node and send one with
+ * the full route when done
+ */
+ info->skip_notify = 1;
+
+ /* For add and replace, send one notification with all nexthops. For
+ * append, send one notification with all appended nexthops.
+ */
+ info->skip_notify_kernel = 1;
+
+ err_nh = NULL;
+ list_for_each_entry(nh, &rt6_nh_list, next) {
+ err = __ip6_ins_rt(nh->fib6_info, info, extack);
+ fib6_info_release(nh->fib6_info);
+
+ if (!err) {
+ /* 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;
+ }
+
+ /* nh->fib6_info is used or freed at this point, reset to NULL*/
+ nh->fib6_info = NULL;
+ if (err) {
+ if (replace && nhn)
+ NL_SET_ERR_MSG_MOD(extack,
+ "multipath route replace failed (check consistency of installed routes)");
+ err_nh = nh;
+ goto add_errout;
+ }
+
+ /* Because each route is added like a single route we remove
+ * these flags after the first nexthop: if there is a collision,
+ * we have already failed to add the first nexthop:
+ * fib6_add_rt2node() has rejected it; when replacing, old
+ * nexthops have been replaced by first new, the rest should
+ * be added to it.
+ */
+ if (cfg->fc_nlinfo.nlh) {
+ cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
+ NLM_F_REPLACE);
+ cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
+ }
+ nhn++;
+ }
+
+ /* An in-kernel notification should only be sent in case the new
+ * multipath route is added as the first route in the node, or if
+ * it was appended to it. We pass 'rt_notif' since it is the first
+ * sibling and might allow us to skip some checks in the replace case.
+ */
+ if (ip6_route_mpath_should_notify(rt_notif)) {
+ enum fib_event_type fib_event;
+
+ if (rt_notif->fib6_nsiblings != nhn - 1)
+ fib_event = FIB_EVENT_ENTRY_APPEND;
+ else
+ fib_event = FIB_EVENT_ENTRY_REPLACE;
+
+ err = call_fib6_multipath_entry_notifiers(info->nl_net,
+ fib_event, rt_notif,
+ nhn - 1, extack);
+ if (err) {
+ /* Delete all the siblings that were just added */
+ err_nh = NULL;
+ goto add_errout;
+ }
+ }
+
+ /* success ... tell user about new route */
+ ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
+ goto cleanup;
+
+add_errout:
+ /* send notification for routes that were added so that
+ * the delete notifications sent by ip6_route_del are
+ * coherent
+ */
+ if (rt_notif)
+ ip6_route_mpath_notify(rt_notif, rt_last, info, nlflags);
+
+ /* Delete routes that were already added */
+ list_for_each_entry(nh, &rt6_nh_list, next) {
+ 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->fib6_info)
+ fib6_info_release(nh->fib6_info);
+ list_del(&nh->next);
+ kfree(nh);
+ }
+
+ return err;
+}
+
+static int ip6_route_multipath_del(struct fib6_config *cfg,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_config r_cfg;
+ struct rtnexthop *rtnh;
+ int last_err = 0;
+ int remaining;
+ int attrlen;
+ int err;
+
+ remaining = cfg->fc_mp_len;
+ rtnh = (struct rtnexthop *)cfg->fc_mp;
+
+ /* Parse a Multipath Entry */
+ while (rtnh_ok(rtnh, remaining)) {
+ memcpy(&r_cfg, cfg, sizeof(*cfg));
+ if (rtnh->rtnh_ifindex)
+ r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
+
+ attrlen = rtnh_attrlen(rtnh);
+ if (attrlen > 0) {
+ struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
+
+ nla = nla_find(attrs, attrlen, RTA_GATEWAY);
+ if (nla) {
+ err = fib6_gw_from_attr(&r_cfg.fc_gateway, nla,
+ extack);
+ if (err) {
+ last_err = err;
+ goto next_rtnh;
+ }
+
+ r_cfg.fc_flags |= RTF_GATEWAY;
+ }
+ }
+ err = ip6_route_del(&r_cfg, extack);
+ if (err)
+ last_err = err;
+
+next_rtnh:
+ rtnh = rtnh_next(rtnh, &remaining);
+ }
+
+ return last_err;
+}
+
+static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_config cfg;
+ int err;
+
+ err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
+ if (err < 0)
+ return err;
+
+ if (cfg.fc_nh_id &&
+ !nexthop_find_by_id(sock_net(skb->sk), cfg.fc_nh_id)) {
+ NL_SET_ERR_MSG(extack, "Nexthop id does not exist");
+ return -EINVAL;
+ }
+
+ if (cfg.fc_mp)
+ return ip6_route_multipath_del(&cfg, extack);
+ else {
+ cfg.fc_delete_all_nh = 1;
+ return ip6_route_del(&cfg, extack);
+ }
+}
+
+static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct fib6_config cfg;
+ int err;
+
+ err = rtm_to_fib6_config(skb, nlh, &cfg, extack);
+ if (err < 0)
+ return err;
+
+ if (cfg.fc_metric == 0)
+ cfg.fc_metric = IP6_RT_PRIO_USER;
+
+ if (cfg.fc_mp)
+ return ip6_route_multipath_add(&cfg, extack);
+ else
+ return ip6_route_add(&cfg, GFP_KERNEL, extack);
+}
+
+/* add the overhead of this fib6_nh to nexthop_len */
+static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
+{
+ int *nexthop_len = arg;
+
+ *nexthop_len += nla_total_size(0) /* RTA_MULTIPATH */
+ + NLA_ALIGN(sizeof(struct rtnexthop))
+ + nla_total_size(16); /* RTA_GATEWAY */
+
+ if (nh->fib_nh_lws) {
+ /* RTA_ENCAP_TYPE */
+ *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
+ /* RTA_ENCAP */
+ *nexthop_len += nla_total_size(2);
+ }
+
+ return 0;
+}
+
+static size_t rt6_nlmsg_size(struct fib6_info *f6i)
+{
+ 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);
+ } else {
+ struct fib6_info *sibling, *next_sibling;
+ struct fib6_nh *nh = f6i->fib6_nh;
+
+ nexthop_len = 0;
+ if (f6i->fib6_nsiblings) {
+ rt6_nh_nlmsg_size(nh, &nexthop_len);
+
+ list_for_each_entry_safe(sibling, next_sibling,
+ &f6i->fib6_siblings, fib6_siblings) {
+ rt6_nh_nlmsg_size(sibling->fib6_nh, &nexthop_len);
+ }
+ }
+ nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
+ }
+
+ return NLMSG_ALIGN(sizeof(struct rtmsg))
+ + nla_total_size(16) /* RTA_SRC */
+ + nla_total_size(16) /* RTA_DST */
+ + nla_total_size(16) /* RTA_GATEWAY */
+ + nla_total_size(16) /* RTA_PREFSRC */
+ + nla_total_size(4) /* RTA_TABLE */
+ + nla_total_size(4) /* RTA_IIF */
+ + nla_total_size(4) /* RTA_OIF */
+ + nla_total_size(4) /* RTA_PRIORITY */
+ + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
+ + nla_total_size(sizeof(struct rta_cacheinfo))
+ + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
+ + nla_total_size(1) /* RTA_PREF */
+ + nexthop_len;
+}
+
+static int rt6_fill_node_nexthop(struct sk_buff *skb, struct nexthop *nh,
+ unsigned char *flags)
+{
+ if (nexthop_is_multipath(nh)) {
+ struct nlattr *mp;
+
+ mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
+ if (!mp)
+ goto nla_put_failure;
+
+ if (nexthop_mpath_fill_node(skb, nh, AF_INET6))
+ goto nla_put_failure;
+
+ nla_nest_end(skb, mp);
+ } else {
+ struct fib6_nh *fib6_nh;
+
+ fib6_nh = nexthop_fib6_nh(nh);
+ if (fib_nexthop_info(skb, &fib6_nh->nh_common, AF_INET6,
+ flags, false) < 0)
+ goto nla_put_failure;
+ }
+
+ return 0;
+
+nla_put_failure:
+ return -EMSGSIZE;
+}
+
+static int rt6_fill_node(struct net *net, struct sk_buff *skb,
+ struct fib6_info *rt, struct dst_entry *dst,
+ struct in6_addr *dest, struct in6_addr *src,
+ int iif, int type, u32 portid, u32 seq,
+ unsigned int flags)
+{
+ struct rt6_info *rt6 = (struct rt6_info *)dst;
+ struct rt6key *rt6_dst, *rt6_src;
+ u32 *pmetrics, table, rt6_flags;
+ unsigned char nh_flags = 0;
+ struct nlmsghdr *nlh;
+ struct rtmsg *rtm;
+ long expires = 0;
+
+ nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
+ if (!nlh)
+ return -EMSGSIZE;
+
+ if (rt6) {
+ rt6_dst = &rt6->rt6i_dst;
+ rt6_src = &rt6->rt6i_src;
+ rt6_flags = rt6->rt6i_flags;
+ } else {
+ rt6_dst = &rt->fib6_dst;
+ rt6_src = &rt->fib6_src;
+ rt6_flags = rt->fib6_flags;
+ }
+
+ rtm = nlmsg_data(nlh);
+ rtm->rtm_family = AF_INET6;
+ rtm->rtm_dst_len = rt6_dst->plen;
+ rtm->rtm_src_len = rt6_src->plen;
+ rtm->rtm_tos = 0;
+ if (rt->fib6_table)
+ table = rt->fib6_table->tb6_id;
+ else
+ table = RT6_TABLE_UNSPEC;
+ rtm->rtm_table = table < 256 ? table : RT_TABLE_COMPAT;
+ if (nla_put_u32(skb, RTA_TABLE, table))
+ goto nla_put_failure;
+
+ rtm->rtm_type = rt->fib6_type;
+ rtm->rtm_flags = 0;
+ rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+ rtm->rtm_protocol = rt->fib6_protocol;
+
+ if (rt6_flags & RTF_CACHE)
+ rtm->rtm_flags |= RTM_F_CLONED;
+
+ 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, &rt6_dst->addr))
+ goto nla_put_failure;
+#ifdef CONFIG_IPV6_SUBTREES
+ if (src) {
+ if (nla_put_in6_addr(skb, RTA_SRC, src))
+ goto nla_put_failure;
+ rtm->rtm_src_len = 128;
+ } else if (rtm->rtm_src_len &&
+ nla_put_in6_addr(skb, RTA_SRC, &rt6_src->addr))
+ goto nla_put_failure;
+#endif
+ if (iif) {
+#ifdef CONFIG_IPV6_MROUTE
+ if (ipv6_addr_is_multicast(&rt6_dst->addr)) {
+ int err = ip6mr_get_route(net, skb, rtm, portid);
+
+ if (err == 0)
+ return 0;
+ if (err < 0)
+ goto nla_put_failure;
+ } else
+#endif
+ if (nla_put_u32(skb, RTA_IIF, iif))
+ goto nla_put_failure;
+ } else if (dest) {
+ struct in6_addr saddr_buf;
+ if (ip6_route_get_saddr(net, rt, dest, 0, &saddr_buf) == 0 &&
+ nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
+ goto nla_put_failure;
+ }
+
+ if (rt->fib6_prefsrc.plen) {
+ struct in6_addr saddr_buf;
+ saddr_buf = rt->fib6_prefsrc.addr;
+ if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
+ goto nla_put_failure;
+ }
+
+ 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->fib6_metric))
+ goto nla_put_failure;
+
+ /* For multipath routes, walk the siblings list and add
+ * each as a nexthop within RTA_MULTIPATH.
+ */
+ if (rt6) {
+ if (rt6_flags & RTF_GATEWAY &&
+ nla_put_in6_addr(skb, RTA_GATEWAY, &rt6->rt6i_gateway))
+ goto nla_put_failure;
+
+ if (dst->dev && nla_put_u32(skb, RTA_OIF, dst->dev->ifindex))
+ goto nla_put_failure;
+
+ if (dst->lwtstate &&
+ lwtunnel_fill_encap(skb, dst->lwtstate, RTA_ENCAP, RTA_ENCAP_TYPE) < 0)
+ goto nla_put_failure;
+ } else if (rt->fib6_nsiblings) {
+ struct fib6_info *sibling, *next_sibling;
+ struct nlattr *mp;
+
+ mp = nla_nest_start_noflag(skb, RTA_MULTIPATH);
+ if (!mp)
+ goto nla_put_failure;
+
+ if (fib_add_nexthop(skb, &rt->fib6_nh->nh_common,
+ rt->fib6_nh->fib_nh_weight, AF_INET6,
+ 0) < 0)
+ goto nla_put_failure;
+
+ list_for_each_entry_safe(sibling, next_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)
+ goto nla_put_failure;
+ }
+
+ nla_nest_end(skb, mp);
+ } else if (rt->nh) {
+ if (nla_put_u32(skb, RTA_NH_ID, rt->nh->id))
+ goto nla_put_failure;
+
+ if (nexthop_is_blackhole(rt->nh))
+ rtm->rtm_type = RTN_BLACKHOLE;
+
+ if (READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode) &&
+ rt6_fill_node_nexthop(skb, rt->nh, &nh_flags) < 0)
+ goto nla_put_failure;
+
+ rtm->rtm_flags |= nh_flags;
+ } else {
+ if (fib_nexthop_info(skb, &rt->fib6_nh->nh_common, AF_INET6,
+ &nh_flags, false) < 0)
+ goto nla_put_failure;
+
+ rtm->rtm_flags |= nh_flags;
+ }
+
+ if (rt6_flags & RTF_EXPIRES) {
+ expires = dst ? dst->expires : rt->expires;
+ expires -= jiffies;
+ }
+
+ if (!dst) {
+ if (READ_ONCE(rt->offload))
+ rtm->rtm_flags |= RTM_F_OFFLOAD;
+ if (READ_ONCE(rt->trap))
+ rtm->rtm_flags |= RTM_F_TRAP;
+ if (READ_ONCE(rt->offload_failed))
+ rtm->rtm_flags |= RTM_F_OFFLOAD_FAILED;
+ }
+
+ if (rtnl_put_cacheinfo(skb, dst, 0, expires, dst ? dst->error : 0) < 0)
+ goto nla_put_failure;
+
+ if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt6_flags)))
+ goto nla_put_failure;
+
+
+ nlmsg_end(skb, nlh);
+ return 0;
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+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 (f6i->fib6_nsiblings) {
+ struct fib6_info *sibling, *next_sibling;
+
+ list_for_each_entry_safe(sibling, next_sibling,
+ &f6i->fib6_siblings, fib6_siblings) {
+ if (sibling->fib6_nh->fib_nh_dev == dev)
+ return true;
+ }
+ }
+
+ 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.fib6_null_entry)
+ return -1;
+
+ if ((filter->flags & RTM_F_PREFIX) &&
+ !(rt->fib6_flags & RTF_PREFIX_RT)) {
+ /* success since this is not a prefix route */
+ return -1;
+ }
+ if (filter->filter_set &&
+ ((filter->rt_type && rt->fib6_type != filter->rt_type) ||
+ (filter->dev && !fib6_info_uses_dev(rt, filter->dev)) ||
+ (filter->protocol && rt->fib6_protocol != filter->protocol))) {
+ return -1;
+ }
+
+ if (filter->filter_set ||
+ !filter->dump_routes || !filter->dump_exceptions) {
+ flags |= NLM_F_DUMP_FILTERED;
+ }
+
+ if (filter->dump_routes) {
+ if (skip) {
+ skip--;
+ } else {
+ if (rt6_fill_node(net, arg->skb, rt, NULL, NULL, NULL,
+ 0, RTM_NEWROUTE,
+ NETLINK_CB(arg->cb->skb).portid,
+ arg->cb->nlh->nlmsg_seq, flags)) {
+ return 0;
+ }
+ count++;
+ }
+ }
+
+ if (filter->dump_exceptions) {
+ struct fib6_nh_exception_dump_walker w = { .dump = arg,
+ .rt = rt,
+ .flags = flags,
+ .skip = skip,
+ .count = 0 };
+ int err;
+
+ 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;
+
+ if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*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);
+
+ rtm = nlmsg_data(nlh);
+ 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;
+ }
+
+ 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:
+ break;
+ default:
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get route request");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh,
+ struct netlink_ext_ack *extack)
+{
+ struct net *net = sock_net(in_skb->sk);
+ struct nlattr *tb[RTA_MAX+1];
+ int err, iif = 0, oif = 0;
+ struct fib6_info *from;
+ struct dst_entry *dst;
+ struct rt6_info *rt;
+ struct sk_buff *skb;
+ struct rtmsg *rtm;
+ struct flowi6 fl6 = {};
+ bool fibmatch;
+
+ err = inet6_rtm_valid_getroute_req(in_skb, nlh, tb, extack);
+ if (err < 0)
+ goto errout;
+
+ err = -EINVAL;
+ 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]) {
+ if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
+ goto errout;
+
+ fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
+ }
+
+ if (tb[RTA_DST]) {
+ if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
+ goto errout;
+
+ fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
+ }
+
+ if (tb[RTA_IIF])
+ iif = nla_get_u32(tb[RTA_IIF]);
+
+ if (tb[RTA_OIF])
+ oif = nla_get_u32(tb[RTA_OIF]);
+
+ if (tb[RTA_MARK])
+ fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
+
+ if (tb[RTA_UID])
+ fl6.flowi6_uid = make_kuid(current_user_ns(),
+ nla_get_u32(tb[RTA_UID]));
+ else
+ fl6.flowi6_uid = iif ? INVALID_UID : current_uid();
+
+ if (tb[RTA_SPORT])
+ fl6.fl6_sport = nla_get_be16(tb[RTA_SPORT]);
+
+ if (tb[RTA_DPORT])
+ fl6.fl6_dport = nla_get_be16(tb[RTA_DPORT]);
+
+ if (tb[RTA_IP_PROTO]) {
+ err = rtm_getroute_parse_ip_proto(tb[RTA_IP_PROTO],
+ &fl6.flowi6_proto, AF_INET6,
+ extack);
+ if (err)
+ goto errout;
+ }
+
+ if (iif) {
+ struct net_device *dev;
+ int flags = 0;
+
+ rcu_read_lock();
+
+ dev = dev_get_by_index_rcu(net, iif);
+ if (!dev) {
+ rcu_read_unlock();
+ err = -ENODEV;
+ goto errout;
+ }
+
+ fl6.flowi6_iif = iif;
+
+ if (!ipv6_addr_any(&fl6.saddr))
+ flags |= RT6_LOOKUP_F_HAS_SADDR;
+
+ dst = ip6_route_input_lookup(net, dev, &fl6, NULL, flags);
+
+ rcu_read_unlock();
+ } else {
+ fl6.flowi6_oif = oif;
+
+ dst = ip6_route_output(net, NULL, &fl6);
+ }
+
+
+ rt = container_of(dst, struct rt6_info, dst);
+ if (rt->dst.error) {
+ err = rt->dst.error;
+ ip6_rt_put(rt);
+ goto errout;
+ }
+
+ if (rt == net->ipv6.ip6_null_entry) {
+ err = rt->dst.error;
+ ip6_rt_put(rt);
+ goto errout;
+ }
+
+ skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+ if (!skb) {
+ ip6_rt_put(rt);
+ err = -ENOBUFS;
+ goto errout;
+ }
+
+ skb_dst_set(skb, &rt->dst);
+
+ 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;
+ }
+
+ err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
+errout:
+ return err;
+}
+
+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;
+ u32 seq;
+ int err;
+
+ err = -ENOBUFS;
+ seq = info->nlh ? info->nlh->nlmsg_seq : 0;
+
+ skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
+ if (!skb)
+ goto errout;
+
+ err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
+ event, info->portid, seq, nlm_flags);
+ if (err < 0) {
+ /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
+ info->nlh, gfp_any());
+ return;
+errout:
+ if (err < 0)
+ 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, NULL, 0,
+ RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
+ if (err < 0) {
+ /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
+ info->nlh, gfp_any());
+ return;
+errout:
+ if (err < 0)
+ 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)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct net *net = dev_net(dev);
+
+ if (!(dev->flags & IFF_LOOPBACK))
+ return NOTIFY_OK;
+
+ if (event == NETDEV_REGISTER) {
+ net->ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = dev;
+ net->ipv6.ip6_null_entry->dst.dev = dev;
+ net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+ net->ipv6.ip6_prohibit_entry->dst.dev = dev;
+ net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
+ net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
+ net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
+#endif
+ } else if (event == NETDEV_UNREGISTER &&
+ dev->reg_state != NETREG_UNREGISTERED) {
+ /* NETDEV_UNREGISTER could be fired for multiple times by
+ * netdev_wait_allrefs(). Make sure we only call this once.
+ */
+ in6_dev_put_clear(&net->ipv6.ip6_null_entry->rt6i_idev);
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+ in6_dev_put_clear(&net->ipv6.ip6_prohibit_entry->rt6i_idev);
+ in6_dev_put_clear(&net->ipv6.ip6_blk_hole_entry->rt6i_idev);
+#endif
+ }
+
+ return NOTIFY_OK;
+}
+
+/*
+ * /proc
+ */
+
+#ifdef CONFIG_PROC_FS
+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,
+ 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),
+ net->ipv6.rt6_stats->fib_discarded_routes);
+
+ return 0;
+}
+#endif /* CONFIG_PROC_FS */
+
+#ifdef CONFIG_SYSCTL
+
+static int ipv6_sysctl_rtcache_flush(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;
+
+ net = (struct net *)ctl->extra1;
+ delay = net->ipv6.sysctl.flush_delay;
+ ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
+ if (ret)
+ return ret;
+
+ fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
+ return 0;
+}
+
+static struct ctl_table ipv6_route_table_template[] = {
+ {
+ .procname = "max_size",
+ .data = &init_net.ipv6.sysctl.ip6_rt_max_size,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "gc_thresh",
+ .data = &ip6_dst_ops_template.gc_thresh,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "flush",
+ .data = &init_net.ipv6.sysctl.flush_delay,
+ .maxlen = sizeof(int),
+ .mode = 0200,
+ .proc_handler = ipv6_sysctl_rtcache_flush
+ },
+ {
+ .procname = "gc_min_interval",
+ .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_jiffies,
+ },
+ {
+ .procname = "gc_timeout",
+ .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_jiffies,
+ },
+ {
+ .procname = "gc_interval",
+ .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_jiffies,
+ },
+ {
+ .procname = "gc_elasticity",
+ .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "mtu_expires",
+ .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_jiffies,
+ },
+ {
+ .procname = "min_adv_mss",
+ .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "gc_min_interval_ms",
+ .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
+ .maxlen = sizeof(int),
+ .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(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+ { }
+};
+
+struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
+{
+ struct ctl_table *table;
+
+ table = kmemdup(ipv6_route_table_template,
+ sizeof(ipv6_route_table_template),
+ GFP_KERNEL);
+
+ if (table) {
+ 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.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;
+ table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
+ 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;
+ table[10].data = &net->ipv6.sysctl.skip_notify_on_dev_down;
+
+ /* Don't export sysctls to unprivileged users */
+ if (net->user_ns != &init_user_ns)
+ table[1].procname = NULL;
+ }
+
+ return table;
+}
+#endif
+
+static int __net_init ip6_route_net_init(struct net *net)
+{
+ int ret = -ENOMEM;
+
+ memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
+ sizeof(net->ipv6.ip6_dst_ops));
+
+ 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_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->rt6i_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.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->rt6i_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.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->rt6i_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 = 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;
+
+ atomic_set(&net->ipv6.ip6_rt_gc_expire, 30*HZ);
+
+ ret = 0;
+out:
+ return ret;
+
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+out_ip6_prohibit_entry:
+ kfree(net->ipv6.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:
+ goto out;
+}
+
+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);
+ kfree(net->ipv6.ip6_blk_hole_entry);
+#endif
+ dst_entries_destroy(&net->ipv6.ip6_dst_ops);
+}
+
+static int __net_init ip6_route_net_init_late(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+ 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;
+}
+
+static void __net_exit ip6_route_net_exit_late(struct net *net)
+{
+#ifdef CONFIG_PROC_FS
+ remove_proc_entry("ipv6_route", net->proc_net);
+ remove_proc_entry("rt6_stats", net->proc_net);
+#endif
+}
+
+static struct pernet_operations ip6_route_net_ops = {
+ .init = ip6_route_net_init,
+ .exit = ip6_route_net_exit,
+};
+
+static int __net_init ipv6_inetpeer_init(struct net *net)
+{
+ struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
+
+ if (!bp)
+ return -ENOMEM;
+ inet_peer_base_init(bp);
+ net->ipv6.peers = bp;
+ return 0;
+}
+
+static void __net_exit ipv6_inetpeer_exit(struct net *net)
+{
+ struct inet_peer_base *bp = net->ipv6.peers;
+
+ net->ipv6.peers = NULL;
+ inetpeer_invalidate_tree(bp);
+ kfree(bp);
+}
+
+static struct pernet_operations ipv6_inetpeer_ops = {
+ .init = ipv6_inetpeer_init,
+ .exit = ipv6_inetpeer_exit,
+};
+
+static struct pernet_operations ip6_route_net_late_ops = {
+ .init = ip6_route_net_init_late,
+ .exit = ip6_route_net_exit_late,
+};
+
+static struct notifier_block ip6_route_dev_notifier = {
+ .notifier_call = ip6_route_dev_notify,
+ .priority = ADDRCONF_NOTIFY_PRIORITY - 10,
+};
+
+void __init ip6_route_init_special_entries(void)
+{
+ /* Registering of the loopback is done before this portion of code,
+ * the loopback reference in rt6_info will not be taken, do it
+ * manually for init_net */
+ init_net.ipv6.fib6_null_entry->fib6_nh->fib_nh_dev = init_net.loopback_dev;
+ init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
+ init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
+ #ifdef CONFIG_IPV6_MULTIPLE_TABLES
+ init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
+ init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
+ init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
+ init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
+ #endif
+}
+
+#if IS_BUILTIN(CONFIG_IPV6)
+#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
+DEFINE_BPF_ITER_FUNC(ipv6_route, struct bpf_iter_meta *meta, struct fib6_info *rt)
+
+BTF_ID_LIST(btf_fib6_info_id)
+BTF_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
+
+int __init ip6_route_init(void)
+{
+ int ret;
+ int cpu;
+
+ ret = -ENOMEM;
+ ip6_dst_ops_template.kmem_cachep =
+ kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL);
+ if (!ip6_dst_ops_template.kmem_cachep)
+ goto out;
+
+ ret = dst_entries_init(&ip6_dst_blackhole_ops);
+ if (ret)
+ goto out_kmem_cache;
+
+ ret = register_pernet_subsys(&ipv6_inetpeer_ops);
+ if (ret)
+ goto out_dst_entries;
+
+ ret = register_pernet_subsys(&ip6_route_net_ops);
+ if (ret)
+ goto out_register_inetpeer;
+
+ ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
+
+ ret = fib6_init();
+ if (ret)
+ goto out_register_subsys;
+
+ ret = xfrm6_init();
+ if (ret)
+ goto out_fib6_init;
+
+ ret = fib6_rules_init();
+ if (ret)
+ goto xfrm6_init;
+
+ ret = register_pernet_subsys(&ip6_route_net_late_ops);
+ if (ret)
+ goto fib6_rules_init;
+
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWROUTE,
+ inet6_rtm_newroute, NULL, 0);
+ if (ret < 0)
+ goto out_register_late_subsys;
+
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELROUTE,
+ inet6_rtm_delroute, NULL, 0);
+ if (ret < 0)
+ goto out_register_late_subsys;
+
+ ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE,
+ inet6_rtm_getroute, NULL,
+ RTNL_FLAG_DOIT_UNLOCKED);
+ if (ret < 0)
+ goto out_register_late_subsys;
+
+ ret = register_netdevice_notifier(&ip6_route_dev_notifier);
+ if (ret)
+ goto out_register_late_subsys;
+
+#if IS_BUILTIN(CONFIG_IPV6)
+#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
+ ret = bpf_iter_register();
+ if (ret)
+ goto out_register_late_subsys;
+#endif
+#endif
+
+ for_each_possible_cpu(cpu) {
+ struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
+
+ INIT_LIST_HEAD(&ul->head);
+ INIT_LIST_HEAD(&ul->quarantine);
+ spin_lock_init(&ul->lock);
+ }
+
+out:
+ return ret;
+
+out_register_late_subsys:
+ rtnl_unregister_all(PF_INET6);
+ unregister_pernet_subsys(&ip6_route_net_late_ops);
+fib6_rules_init:
+ fib6_rules_cleanup();
+xfrm6_init:
+ xfrm6_fini();
+out_fib6_init:
+ fib6_gc_cleanup();
+out_register_subsys:
+ unregister_pernet_subsys(&ip6_route_net_ops);
+out_register_inetpeer:
+ unregister_pernet_subsys(&ipv6_inetpeer_ops);
+out_dst_entries:
+ dst_entries_destroy(&ip6_dst_blackhole_ops);
+out_kmem_cache:
+ kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
+ goto out;
+}
+
+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();
+ xfrm6_fini();
+ fib6_gc_cleanup();
+ unregister_pernet_subsys(&ipv6_inetpeer_ops);
+ unregister_pernet_subsys(&ip6_route_net_ops);
+ dst_entries_destroy(&ip6_dst_blackhole_ops);
+ kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
+}