diff options
Diffstat (limited to 'net/ipv6/route.c')
| -rw-r--r-- | net/ipv6/route.c | 2783 |
1 files changed, 2783 insertions, 0 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c new file mode 100644 index 0000000..89dc699 --- /dev/null +++ b/net/ipv6/route.c @@ -0,0 +1,2783 @@ +/* + * Linux INET6 implementation + * FIB front-end. + * + * Authors: + * Pedro Roque <roque@di.fc.ul.pt> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +/* Changes: + * + * 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. + */ + +#include <linux/capability.h> +#include <linux/errno.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 <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/xfrm.h> +#include <net/netevent.h> +#include <net/netlink.h> + +#include <asm/uaccess.h> + +#ifdef CONFIG_SYSCTL +#include <linux/sysctl.h> +#endif + +/* Set to 3 to get tracing. */ +#define RT6_DEBUG 2 + +#if RT6_DEBUG >= 3 +#define RDBG(x) printk x +#define RT6_TRACE(x...) printk(KERN_DEBUG x) +#else +#define RDBG(x) +#define RT6_TRACE(x...) do { ; } while (0) +#endif + +#define CLONE_OFFLINK_ROUTE 0 + +static struct rt6_info * ip6_rt_copy(struct rt6_info *ort); +static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie); +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 int ip6_dst_gc(struct dst_ops *ops); + +static int ip6_pkt_discard(struct sk_buff *skb); +static int ip6_pkt_discard_out(struct sk_buff *skb); +static void ip6_link_failure(struct sk_buff *skb); +static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu); + +#ifdef CONFIG_IPV6_ROUTE_INFO +static struct rt6_info *rt6_add_route_info(struct net *net, + struct in6_addr *prefix, int prefixlen, + struct in6_addr *gwaddr, int ifindex, + unsigned pref); +static struct rt6_info *rt6_get_route_info(struct net *net, + struct in6_addr *prefix, int prefixlen, + struct in6_addr *gwaddr, int ifindex); +#endif + +static struct dst_ops ip6_dst_ops_template = { + .family = AF_INET6, + .protocol = __constant_htons(ETH_P_IPV6), + .gc = ip6_dst_gc, + .gc_thresh = 1024, + .check = ip6_dst_check, + .destroy = ip6_dst_destroy, + .ifdown = ip6_dst_ifdown, + .negative_advice = ip6_negative_advice, + .link_failure = ip6_link_failure, + .update_pmtu = ip6_rt_update_pmtu, + .local_out = __ip6_local_out, + .entry_size = sizeof(struct rt6_info), + .entries = ATOMIC_INIT(0), +}; + +static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) +{ +} + +static struct dst_ops ip6_dst_blackhole_ops = { + .family = AF_INET6, + .protocol = __constant_htons(ETH_P_IPV6), + .destroy = ip6_dst_destroy, + .check = ip6_dst_check, + .update_pmtu = ip6_rt_blackhole_update_pmtu, + .entry_size = sizeof(struct rt6_info), + .entries = ATOMIC_INIT(0), +}; + +static struct rt6_info ip6_null_entry_template = { + .u = { + .dst = { + .__refcnt = ATOMIC_INIT(1), + .__use = 1, + .obsolete = -1, + .error = -ENETUNREACH, + .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, + .input = ip6_pkt_discard, + .output = ip6_pkt_discard_out, + } + }, + .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), + .rt6i_metric = ~(u32) 0, + .rt6i_ref = ATOMIC_INIT(1), +}; + +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + +static int ip6_pkt_prohibit(struct sk_buff *skb); +static int ip6_pkt_prohibit_out(struct sk_buff *skb); + +static struct rt6_info ip6_prohibit_entry_template = { + .u = { + .dst = { + .__refcnt = ATOMIC_INIT(1), + .__use = 1, + .obsolete = -1, + .error = -EACCES, + .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, + .input = ip6_pkt_prohibit, + .output = ip6_pkt_prohibit_out, + } + }, + .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), + .rt6i_metric = ~(u32) 0, + .rt6i_ref = ATOMIC_INIT(1), +}; + +static struct rt6_info ip6_blk_hole_entry_template = { + .u = { + .dst = { + .__refcnt = ATOMIC_INIT(1), + .__use = 1, + .obsolete = -1, + .error = -EINVAL, + .metrics = { [RTAX_HOPLIMIT - 1] = 255, }, + .input = dst_discard, + .output = dst_discard, + } + }, + .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), + .rt6i_metric = ~(u32) 0, + .rt6i_ref = ATOMIC_INIT(1), +}; + +#endif + +/* allocate dst with ip6_dst_ops */ +static inline struct rt6_info *ip6_dst_alloc(struct dst_ops *ops) +{ + return (struct rt6_info *)dst_alloc(ops); +} + +static void ip6_dst_destroy(struct dst_entry *dst) +{ + struct rt6_info *rt = (struct rt6_info *)dst; + struct inet6_dev *idev = rt->rt6i_idev; + + if (idev != NULL) { + rt->rt6i_idev = NULL; + in6_dev_put(idev); + } +} + +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; + struct net_device *loopback_dev = + dev_net(dev)->loopback_dev; + + if (dev != loopback_dev && idev != NULL && idev->dev == dev) { + struct inet6_dev *loopback_idev = + in6_dev_get(loopback_dev); + if (loopback_idev != NULL) { + rt->rt6i_idev = loopback_idev; + in6_dev_put(idev); + } + } +} + +static __inline__ int rt6_check_expired(const struct rt6_info *rt) +{ + return (rt->rt6i_flags & RTF_EXPIRES && + time_after(jiffies, rt->rt6i_expires)); +} + +static inline int rt6_need_strict(struct in6_addr *daddr) +{ + return (ipv6_addr_type(daddr) & + (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK)); +} + +/* + * Route lookup. Any table->tb6_lock is implied. + */ + +static inline struct rt6_info *rt6_device_match(struct net *net, + struct rt6_info *rt, + struct in6_addr *saddr, + int oif, + int flags) +{ + struct rt6_info *local = NULL; + struct rt6_info *sprt; + + if (!oif && ipv6_addr_any(saddr)) + goto out; + + for (sprt = rt; sprt; sprt = sprt->u.dst.rt6_next) { + struct net_device *dev = sprt->rt6i_dev; + + if (oif) { + if (dev->ifindex == oif) + return sprt; + if (dev->flags & IFF_LOOPBACK) { + if (sprt->rt6i_idev == NULL || + sprt->rt6i_idev->dev->ifindex != oif) { + if (flags & RT6_LOOKUP_F_IFACE && oif) + continue; + if (local && (!oif || + local->rt6i_idev->dev->ifindex == oif)) + continue; + } + local = sprt; + } + } else { + if (ipv6_chk_addr(net, saddr, dev, + flags & RT6_LOOKUP_F_IFACE)) + return sprt; + } + } + + if (oif) { + if (local) + return local; + + if (flags & RT6_LOOKUP_F_IFACE) + return net->ipv6.ip6_null_entry; + } +out: + return rt; +} + +#ifdef CONFIG_IPV6_ROUTER_PREF +static void rt6_probe(struct rt6_info *rt) +{ + struct neighbour *neigh = rt ? rt->rt6i_nexthop : NULL; + /* + * 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 (!neigh || (neigh->nud_state & NUD_VALID)) + return; + read_lock_bh(&neigh->lock); + if (!(neigh->nud_state & NUD_VALID) && + time_after(jiffies, neigh->updated + rt->rt6i_idev->cnf.rtr_probe_interval)) { + struct in6_addr mcaddr; + struct in6_addr *target; + + neigh->updated = jiffies; + read_unlock_bh(&neigh->lock); + + target = (struct in6_addr *)&neigh->primary_key; + addrconf_addr_solict_mult(target, &mcaddr); + ndisc_send_ns(rt->rt6i_dev, NULL, target, &mcaddr, NULL); + } else + read_unlock_bh(&neigh->lock); +} +#else +static inline void rt6_probe(struct rt6_info *rt) +{ + return; +} +#endif + +/* + * Default Router Selection (RFC 2461 6.3.6) + */ +static inline int rt6_check_dev(struct rt6_info *rt, int oif) +{ + struct net_device *dev = rt->rt6i_dev; + if (!oif || dev->ifindex == oif) + return 2; + if ((dev->flags & IFF_LOOPBACK) && + rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif) + return 1; + return 0; +} + +static inline int rt6_check_neigh(struct rt6_info *rt) +{ + struct neighbour *neigh = rt->rt6i_nexthop; + int m; + if (rt->rt6i_flags & RTF_NONEXTHOP || + !(rt->rt6i_flags & RTF_GATEWAY)) + m = 1; + else if (neigh) { + read_lock_bh(&neigh->lock); + if (neigh->nud_state & NUD_VALID) + m = 2; +#ifdef CONFIG_IPV6_ROUTER_PREF + else if (neigh->nud_state & NUD_FAILED) + m = 0; +#endif + else + m = 1; + read_unlock_bh(&neigh->lock); + } else + m = 0; + return m; +} + +static int rt6_score_route(struct rt6_info *rt, int oif, + int strict) +{ + int m, n; + + m = rt6_check_dev(rt, oif); + if (!m && (strict & RT6_LOOKUP_F_IFACE)) + return -1; +#ifdef CONFIG_IPV6_ROUTER_PREF + m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2; +#endif + n = rt6_check_neigh(rt); + if (!n && (strict & RT6_LOOKUP_F_REACHABLE)) + return -1; + return m; +} + +static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict, + int *mpri, struct rt6_info *match) +{ + int m; + + if (rt6_check_expired(rt)) + goto out; + + m = rt6_score_route(rt, oif, strict); + if (m < 0) + goto out; + + if (m > *mpri) { + if (strict & RT6_LOOKUP_F_REACHABLE) + rt6_probe(match); + *mpri = m; + match = rt; + } else if (strict & RT6_LOOKUP_F_REACHABLE) { + rt6_probe(rt); + } + +out: + return match; +} + +static struct rt6_info *find_rr_leaf(struct fib6_node *fn, + struct rt6_info *rr_head, + u32 metric, int oif, int strict) +{ + struct rt6_info *rt, *match; + int mpri = -1; + + match = NULL; + for (rt = rr_head; rt && rt->rt6i_metric == metric; + rt = rt->u.dst.rt6_next) + match = find_match(rt, oif, strict, &mpri, match); + for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric; + rt = rt->u.dst.rt6_next) + match = find_match(rt, oif, strict, &mpri, match); + + return match; +} + +static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict) +{ + struct rt6_info *match, *rt0; + struct net *net; + + RT6_TRACE("%s(fn->leaf=%p, oif=%d)\n", + __func__, fn->leaf, oif); + + rt0 = fn->rr_ptr; + if (!rt0) + fn->rr_ptr = rt0 = fn->leaf; + + match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict); + + if (!match && + (strict & RT6_LOOKUP_F_REACHABLE)) { + struct rt6_info *next = rt0->u.dst.rt6_next; + + /* no entries matched; do round-robin */ + if (!next || next->rt6i_metric != rt0->rt6i_metric) + next = fn->leaf; + + if (next != rt0) + fn->rr_ptr = next; + } + + RT6_TRACE("%s() => %p\n", + __func__, match); + + net = dev_net(rt0->rt6i_dev); + return (match ? match : net->ipv6.ip6_null_entry); +} + +#ifdef CONFIG_IPV6_ROUTE_INFO +int rt6_route_rcv(struct net_device *dev, u8 *opt, int len, + 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 rt6_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) + pref = ICMPV6_ROUTER_PREF_MEDIUM; + + 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; + } + + rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr, + dev->ifindex); + + if (rt && !lifetime) { + ip6_del_rt(rt); + rt = NULL; + } + + if (!rt && lifetime) + rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex, + pref); + else if (rt) + rt->rt6i_flags = RTF_ROUTEINFO | + (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); + + if (rt) { + if (!addrconf_finite_timeout(lifetime)) { + rt->rt6i_flags &= ~RTF_EXPIRES; + } else { + rt->rt6i_expires = jiffies + HZ * lifetime; + rt->rt6i_flags |= RTF_EXPIRES; + } + dst_release(&rt->u.dst); + } + return 0; +} +#endif + +#define BACKTRACK(__net, saddr) \ +do { \ + if (rt == __net->ipv6.ip6_null_entry) { \ + struct fib6_node *pn; \ + while (1) { \ + if (fn->fn_flags & RTN_TL_ROOT) \ + goto out; \ + pn = fn->parent; \ + if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn) \ + fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr); \ + else \ + fn = pn; \ + if (fn->fn_flags & RTN_RTINFO) \ + goto restart; \ + } \ + } \ +} while(0) + +static struct rt6_info *ip6_pol_route_lookup(struct net *net, + struct fib6_table *table, + struct flowi *fl, int flags) +{ + struct fib6_node *fn; + struct rt6_info *rt; + + read_lock_bh(&table->tb6_lock); + fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); +restart: + rt = fn->leaf; + rt = rt6_device_match(net, rt, &fl->fl6_src, fl->oif, flags); + BACKTRACK(net, &fl->fl6_src); +out: + dst_use(&rt->u.dst, jiffies); + read_unlock_bh(&table->tb6_lock); + return rt; + +} + +struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr, + const struct in6_addr *saddr, int oif, int strict) +{ + struct flowi fl = { + .oif = oif, + .nl_u = { + .ip6_u = { + .daddr = *daddr, + }, + }, + }; + struct dst_entry *dst; + int flags = strict ? RT6_LOOKUP_F_IFACE : 0; + + if (saddr) { + memcpy(&fl.fl6_src, saddr, sizeof(*saddr)); + flags |= RT6_LOOKUP_F_HAS_SADDR; + } + + dst = fib6_rule_lookup(net, &fl, 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 freed. In any case, if caller does not hold it, it may + be destroyed. + */ + +static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info) +{ + int err; + struct fib6_table *table; + + table = rt->rt6i_table; + write_lock_bh(&table->tb6_lock); + err = fib6_add(&table->tb6_root, rt, info); + write_unlock_bh(&table->tb6_lock); + + return err; +} + +int ip6_ins_rt(struct rt6_info *rt) +{ + struct nl_info info = { + .nl_net = dev_net(rt->rt6i_dev), + }; + return __ip6_ins_rt(rt, &info); +} + +static struct rt6_info *rt6_alloc_cow(struct rt6_info *ort, struct in6_addr *daddr, + struct in6_addr *saddr) +{ + struct rt6_info *rt; + + /* + * Clone the route. + */ + + rt = ip6_rt_copy(ort); + + if (rt) { + if (!(rt->rt6i_flags&RTF_GATEWAY)) { + if (rt->rt6i_dst.plen != 128 && + ipv6_addr_equal(&rt->rt6i_dst.addr, daddr)) + rt->rt6i_flags |= RTF_ANYCAST; + ipv6_addr_copy(&rt->rt6i_gateway, daddr); + } + + ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); + rt->rt6i_dst.plen = 128; + rt->rt6i_flags |= RTF_CACHE; + rt->u.dst.flags |= DST_HOST; + +#ifdef CONFIG_IPV6_SUBTREES + if (rt->rt6i_src.plen && saddr) { + ipv6_addr_copy(&rt->rt6i_src.addr, saddr); + rt->rt6i_src.plen = 128; + } +#endif + + rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); + + } + + return rt; +} + +static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, struct in6_addr *daddr) +{ + struct rt6_info *rt = ip6_rt_copy(ort); + if (rt) { + ipv6_addr_copy(&rt->rt6i_dst.addr, daddr); + rt->rt6i_dst.plen = 128; + rt->rt6i_flags |= RTF_CACHE; + rt->u.dst.flags |= DST_HOST; + rt->rt6i_nexthop = neigh_clone(ort->rt6i_nexthop); + } + return rt; +} + +static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif, + struct flowi *fl, int flags) +{ + struct fib6_node *fn; + struct rt6_info *rt, *nrt; + int strict = 0; + int attempts = 3; + int err; + int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE; + + strict |= flags & RT6_LOOKUP_F_IFACE; + +relookup: + read_lock_bh(&table->tb6_lock); + +restart_2: + fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); + +restart: + rt = rt6_select(fn, oif, strict | reachable); + + BACKTRACK(net, &fl->fl6_src); + if (rt == net->ipv6.ip6_null_entry || + rt->rt6i_flags & RTF_CACHE) + goto out; + + dst_hold(&rt->u.dst); + read_unlock_bh(&table->tb6_lock); + + if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) + nrt = rt6_alloc_cow(rt, &fl->fl6_dst, &fl->fl6_src); + else { +#if CLONE_OFFLINK_ROUTE + nrt = rt6_alloc_clone(rt, &fl->fl6_dst); +#else + goto out2; +#endif + } + + dst_release(&rt->u.dst); + rt = nrt ? : net->ipv6.ip6_null_entry; + + dst_hold(&rt->u.dst); + if (nrt) { + err = ip6_ins_rt(nrt); + if (!err) + goto out2; + } + + if (--attempts <= 0) + goto out2; + + /* + * Race condition! In the gap, when table->tb6_lock was + * released someone could insert this route. Relookup. + */ + dst_release(&rt->u.dst); + goto relookup; + +out: + if (reachable) { + reachable = 0; + goto restart_2; + } + dst_hold(&rt->u.dst); + read_unlock_bh(&table->tb6_lock); +out2: + rt->u.dst.lastuse = jiffies; + rt->u.dst.__use++; + + return rt; +} + +static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table, + struct flowi *fl, int flags) +{ + return ip6_pol_route(net, table, fl->iif, fl, flags); +} + +void ip6_route_input(struct sk_buff *skb) +{ + struct ipv6hdr *iph = ipv6_hdr(skb); + struct net *net = dev_net(skb->dev); + int flags = RT6_LOOKUP_F_HAS_SADDR; + struct flowi fl = { + .iif = skb->dev->ifindex, + .nl_u = { + .ip6_u = { + .daddr = iph->daddr, + .saddr = iph->saddr, + .flowlabel = (* (__be32 *) iph)&IPV6_FLOWINFO_MASK, + }, + }, + .mark = skb->mark, + .proto = iph->nexthdr, + }; + + if (rt6_need_strict(&iph->daddr)) + flags |= RT6_LOOKUP_F_IFACE; + + skb->dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input); +} + +static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table, + struct flowi *fl, int flags) +{ + return ip6_pol_route(net, table, fl->oif, fl, flags); +} + +struct dst_entry * ip6_route_output(struct net *net, struct sock *sk, + struct flowi *fl) +{ + int flags = 0; + + if (rt6_need_strict(&fl->fl6_dst)) + flags |= RT6_LOOKUP_F_IFACE; + + if (!ipv6_addr_any(&fl->fl6_src)) + flags |= RT6_LOOKUP_F_HAS_SADDR; + else if (sk) { + unsigned int prefs = inet6_sk(sk)->srcprefs; + if (prefs & IPV6_PREFER_SRC_TMP) + flags |= RT6_LOOKUP_F_SRCPREF_TMP; + if (prefs & IPV6_PREFER_SRC_PUBLIC) + flags |= RT6_LOOKUP_F_SRCPREF_PUBLIC; + if (prefs & IPV6_PREFER_SRC_COA) + flags |= RT6_LOOKUP_F_SRCPREF_COA; + } + + return fib6_rule_lookup(net, fl, flags, ip6_pol_route_output); +} + +EXPORT_SYMBOL(ip6_route_output); + +int ip6_dst_blackhole(struct sock *sk, struct dst_entry **dstp, struct flowi *fl) +{ + struct rt6_info *ort = (struct rt6_info *) *dstp; + struct rt6_info *rt = (struct rt6_info *) + dst_alloc(&ip6_dst_blackhole_ops); + struct dst_entry *new = NULL; + + if (rt) { + new = &rt->u.dst; + + atomic_set(&new->__refcnt, 1); + new->__use = 1; + new->input = dst_discard; + new->output = dst_discard; + + memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32)); + new->dev = ort->u.dst.dev; + if (new->dev) + dev_hold(new->dev); + rt->rt6i_idev = ort->rt6i_idev; + if (rt->rt6i_idev) + in6_dev_hold(rt->rt6i_idev); + rt->rt6i_expires = 0; + + ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway); + rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; + rt->rt6i_metric = 0; + + memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key)); +#ifdef CONFIG_IPV6_SUBTREES + memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key)); +#endif + + dst_free(new); + } + + dst_release(*dstp); + *dstp = new; + return (new ? 0 : -ENOMEM); +} +EXPORT_SYMBOL_GPL(ip6_dst_blackhole); + +/* + * Destination cache support functions + */ + +static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie) +{ + struct rt6_info *rt; + + rt = (struct rt6_info *) dst; + + if (rt && rt->rt6i_node && (rt->rt6i_node->fn_sernum == cookie)) + return dst; + + return NULL; +} + +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) + ip6_del_rt(rt); + else + dst_release(dst); + } + return NULL; +} + +static void ip6_link_failure(struct sk_buff *skb) +{ + struct rt6_info *rt; + + icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0, skb->dev); + + rt = (struct rt6_info *) skb->dst; + if (rt) { + if (rt->rt6i_flags&RTF_CACHE) { + dst_set_expires(&rt->u.dst, 0); + rt->rt6i_flags |= RTF_EXPIRES; + } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) + rt->rt6i_node->fn_sernum = -1; + } +} + +static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu) +{ + struct rt6_info *rt6 = (struct rt6_info*)dst; + + if (mtu < dst_mtu(dst) && rt6->rt6i_dst.plen == 128) { + rt6->rt6i_flags |= RTF_MODIFIED; + if (mtu < IPV6_MIN_MTU) { + mtu = IPV6_MIN_MTU; + dst->metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; + } + dst->metrics[RTAX_MTU-1] = mtu; + call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst); + } +} + +static int ipv6_get_mtu(struct net_device *dev); + +static inline unsigned int ipv6_advmss(struct net *net, unsigned int mtu) +{ + 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; +} + +static struct dst_entry *icmp6_dst_gc_list; +static DEFINE_SPINLOCK(icmp6_dst_lock); + +struct dst_entry *icmp6_dst_alloc(struct net_device *dev, + struct neighbour *neigh, + const struct in6_addr *addr) +{ + struct rt6_info *rt; + struct inet6_dev *idev = in6_dev_get(dev); + struct net *net = dev_net(dev); + + if (unlikely(idev == NULL)) + return NULL; + + rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); + if (unlikely(rt == NULL)) { + in6_dev_put(idev); + goto out; + } + + dev_hold(dev); + if (neigh) + neigh_hold(neigh); + else + neigh = ndisc_get_neigh(dev, addr); + + rt->rt6i_dev = dev; + rt->rt6i_idev = idev; + rt->rt6i_nexthop = neigh; + atomic_set(&rt->u.dst.__refcnt, 1); + rt->u.dst.metrics[RTAX_HOPLIMIT-1] = 255; + rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); + rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); + rt->u.dst.output = ip6_output; + +#if 0 /* there's no chance to use these for ndisc */ + rt->u.dst.flags = ipv6_addr_type(addr) & IPV6_ADDR_UNICAST + ? DST_HOST + : 0; + ipv6_addr_copy(&rt->rt6i_dst.addr, addr); + rt->rt6i_dst.plen = 128; +#endif + + spin_lock_bh(&icmp6_dst_lock); + rt->u.dst.next = icmp6_dst_gc_list; + icmp6_dst_gc_list = &rt->u.dst; + spin_unlock_bh(&icmp6_dst_lock); + + fib6_force_start_gc(net); + +out: + return &rt->u.dst; +} + +int icmp6_dst_gc(void) +{ + struct dst_entry *dst, *next, **pprev; + int more = 0; + + next = NULL; + + spin_lock_bh(&icmp6_dst_lock); + pprev = &icmp6_dst_gc_list; + + while ((dst = *pprev) != NULL) { + if (!atomic_read(&dst->__refcnt)) { + *pprev = dst->next; + dst_free(dst); + } else { + pprev = &dst->next; + ++more; + } + } + + spin_unlock_bh(&icmp6_dst_lock); + + return more; +} + +static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg), + void *arg) +{ + struct dst_entry *dst, **pprev; + + spin_lock_bh(&icmp6_dst_lock); + pprev = &icmp6_dst_gc_list; + while ((dst = *pprev) != NULL) { + struct rt6_info *rt = (struct rt6_info *) dst; + if (func(rt, arg)) { + *pprev = dst->next; + dst_free(dst); + } else { + pprev = &dst->next; + } + } + spin_unlock_bh(&icmp6_dst_lock); +} + +static int ip6_dst_gc(struct dst_ops *ops) +{ + unsigned long now = jiffies; + struct net *net = ops->dst_net; + int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval; + int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size; + int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity; + int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout; + unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc; + + if (time_after(rt_last_gc + rt_min_interval, now) && + atomic_read(&ops->entries) <= rt_max_size) + goto out; + + net->ipv6.ip6_rt_gc_expire++; + fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net); + net->ipv6.ip6_rt_last_gc = now; + if (atomic_read(&ops->entries) < ops->gc_thresh) + net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1; +out: + net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity; + return (atomic_read(&ops->entries) > rt_max_size); +} + +/* Clean host part of a prefix. Not necessary in radix tree, + but results in cleaner routing tables. + + Remove it only when all the things will work! + */ + +static int ipv6_get_mtu(struct net_device *dev) +{ + int mtu = IPV6_MIN_MTU; + struct inet6_dev *idev; + + idev = in6_dev_get(dev); + if (idev) { + mtu = idev->cnf.mtu6; + in6_dev_put(idev); + } + return mtu; +} + +int ip6_dst_hoplimit(struct dst_entry *dst) +{ + int hoplimit = dst_metric(dst, RTAX_HOPLIMIT); + if (hoplimit < 0) { + struct net_device *dev = dst->dev; + struct inet6_dev *idev = in6_dev_get(dev); + if (idev) { + hoplimit = idev->cnf.hop_limit; + in6_dev_put(idev); + } else + hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; + } + return hoplimit; +} + +/* + * + */ + +int ip6_route_add(struct fib6_config *cfg) +{ + int err; + struct net *net = cfg->fc_nlinfo.nl_net; + struct rt6_info *rt = NULL; + struct net_device *dev = NULL; + struct inet6_dev *idev = NULL; + struct fib6_table *table; + int addr_type; + + if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128) + return -EINVAL; +#ifndef CONFIG_IPV6_SUBTREES + if (cfg->fc_src_len) + return -EINVAL; +#endif + if (cfg->fc_ifindex) { + err = -ENODEV; + dev = dev_get_by_index(net, cfg->fc_ifindex); + if (!dev) + goto out; + idev = in6_dev_get(dev); + if (!idev) + goto out; + } + + if (cfg->fc_metric == 0) + cfg->fc_metric = IP6_RT_PRIO_USER; + + table = fib6_new_table(net, cfg->fc_table); + if (table == NULL) { + err = -ENOBUFS; + goto out; + } + + rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); + + if (rt == NULL) { + err = -ENOMEM; + goto out; + } + + rt->u.dst.obsolete = -1; + rt->rt6i_expires = (cfg->fc_flags & RTF_EXPIRES) ? + jiffies + clock_t_to_jiffies(cfg->fc_expires) : + 0; + + if (cfg->fc_protocol == RTPROT_UNSPEC) + cfg->fc_protocol = RTPROT_BOOT; + rt->rt6i_protocol = cfg->fc_protocol; + + addr_type = ipv6_addr_type(&cfg->fc_dst); + + if (addr_type & IPV6_ADDR_MULTICAST) + rt->u.dst.input = ip6_mc_input; + else + rt->u.dst.input = ip6_forward; + + rt->u.dst.output = ip6_output; + + ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len); + rt->rt6i_dst.plen = cfg->fc_dst_len; + if (rt->rt6i_dst.plen == 128) + rt->u.dst.flags = DST_HOST; + +#ifdef CONFIG_IPV6_SUBTREES + ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len); + rt->rt6i_src.plen = cfg->fc_src_len; +#endif + + rt->rt6i_metric = cfg->fc_metric; + + /* We cannot add true routes via loopback here, + they would result in kernel looping; promote them to reject routes + */ + if ((cfg->fc_flags & RTF_REJECT) || + (dev && (dev->flags&IFF_LOOPBACK) && !(addr_type&IPV6_ADDR_LOOPBACK))) { + /* hold loopback dev/idev if we haven't done so. */ + if (dev != net->loopback_dev) { + if (dev) { + dev_put(dev); + in6_dev_put(idev); + } + dev = net->loopback_dev; + dev_hold(dev); + idev = in6_dev_get(dev); + if (!idev) { + err = -ENODEV; + goto out; + } + } + rt->u.dst.output = ip6_pkt_discard_out; + rt->u.dst.input = ip6_pkt_discard; + rt->u.dst.error = -ENETUNREACH; + rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP; + goto install_route; + } + + if (cfg->fc_flags & RTF_GATEWAY) { + struct in6_addr *gw_addr; + int gwa_type; + + gw_addr = &cfg->fc_gateway; + ipv6_addr_copy(&rt->rt6i_gateway, gw_addr); + gwa_type = ipv6_addr_type(gw_addr); + + if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) { + struct rt6_info *grt; + + /* IPv6 strictly inhibits using not link-local + addresses as nexthop address. + Otherwise, router will not able to send redirects. + It is very good, but in some (rare!) circumstances + (SIT, PtP, NBMA NOARP links) it is handy to allow + some exceptions. --ANK + */ + err = -EINVAL; + if (!(gwa_type&IPV6_ADDR_UNICAST)) + goto out; + + grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1); + + err = -EHOSTUNREACH; + if (grt == NULL) + goto out; + if (dev) { + if (dev != grt->rt6i_dev) { + dst_release(&grt->u.dst); + goto out; + } + } else { + dev = grt->rt6i_dev; + idev = grt->rt6i_idev; + dev_hold(dev); + in6_dev_hold(grt->rt6i_idev); + } + if (!(grt->rt6i_flags&RTF_GATEWAY)) + err = 0; + dst_release(&grt->u.dst); + + if (err) + goto out; + } + err = -EINVAL; + if (dev == NULL || (dev->flags&IFF_LOOPBACK)) + goto out; + } + + err = -ENODEV; + if (dev == NULL) + goto out; + + if (cfg->fc_flags & (RTF_GATEWAY | RTF_NONEXTHOP)) { + rt->rt6i_nexthop = __neigh_lookup_errno(&nd_tbl, &rt->rt6i_gateway, dev); + if (IS_ERR(rt->rt6i_nexthop)) { + err = PTR_ERR(rt->rt6i_nexthop); + rt->rt6i_nexthop = NULL; + goto out; + } + } + + rt->rt6i_flags = cfg->fc_flags; + +install_route: + if (cfg->fc_mx) { + struct nlattr *nla; + int remaining; + + nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) { + int type = nla_type(nla); + + if (type) { + if (type > RTAX_MAX) { + err = -EINVAL; + goto out; + } + + rt->u.dst.metrics[type - 1] = nla_get_u32(nla); + } + } + } + + if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0) + rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; + if (!dst_mtu(&rt->u.dst)) + rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(dev); + if (!dst_metric(&rt->u.dst, RTAX_ADVMSS)) + rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); + rt->u.dst.dev = dev; + rt->rt6i_idev = idev; + rt->rt6i_table = table; + + cfg->fc_nlinfo.nl_net = dev_net(dev); + + return __ip6_ins_rt(rt, &cfg->fc_nlinfo); + +out: + if (dev) + dev_put(dev); + if (idev) + in6_dev_put(idev); + if (rt) + dst_free(&rt->u.dst); + return err; +} + +static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info) +{ + int err; + struct fib6_table *table; + struct net *net = dev_net(rt->rt6i_dev); + + if (rt == net->ipv6.ip6_null_entry) + return -ENOENT; + + table = rt->rt6i_table; + write_lock_bh(&table->tb6_lock); + + err = fib6_del(rt, info); + dst_release(&rt->u.dst); + + write_unlock_bh(&table->tb6_lock); + + return err; +} + +int ip6_del_rt(struct rt6_info *rt) +{ + struct nl_info info = { + .nl_net = dev_net(rt->rt6i_dev), + }; + return __ip6_del_rt(rt, &info); +} + +static int ip6_route_del(struct fib6_config *cfg) +{ + struct fib6_table *table; + struct fib6_node *fn; + struct rt6_info *rt; + int err = -ESRCH; + + table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table); + if (table == NULL) + return err; + + read_lock_bh(&table->tb6_lock); + + fn = fib6_locate(&table->tb6_root, + &cfg->fc_dst, cfg->fc_dst_len, + &cfg->fc_src, cfg->fc_src_len); + + if (fn) { + for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { + if (cfg->fc_ifindex && + (rt->rt6i_dev == NULL || + rt->rt6i_dev->ifindex != cfg->fc_ifindex)) + continue; + if (cfg->fc_flags & RTF_GATEWAY && + !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway)) + continue; + if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric) + continue; + dst_hold(&rt->u.dst); + read_unlock_bh(&table->tb6_lock); + + return __ip6_del_rt(rt, &cfg->fc_nlinfo); + } + } + read_unlock_bh(&table->tb6_lock); + + return err; +} + +/* + * Handle redirects + */ +struct ip6rd_flowi { + struct flowi fl; + struct in6_addr gateway; +}; + +static struct rt6_info *__ip6_route_redirect(struct net *net, + struct fib6_table *table, + struct flowi *fl, + int flags) +{ + struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl; + struct rt6_info *rt; + struct fib6_node *fn; + + /* + * Get the "current" route for this destination and + * check if the redirect has come from approriate router. + * + * RFC 2461 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. + */ + + read_lock_bh(&table->tb6_lock); + fn = fib6_lookup(&table->tb6_root, &fl->fl6_dst, &fl->fl6_src); +restart: + for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { + /* + * Current route is on-link; redirect is always invalid. + * + * Seems, previous statement is not true. It could + * be node, which looks for us as on-link (f.e. proxy ndisc) + * But then router serving it might decide, that we should + * know truth 8)8) --ANK (980726). + */ + if (rt6_check_expired(rt)) + continue; + if (!(rt->rt6i_flags & RTF_GATEWAY)) + continue; + if (fl->oif != rt->rt6i_dev->ifindex) + continue; + if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway)) + continue; + break; + } + + if (!rt) + rt = net->ipv6.ip6_null_entry; + BACKTRACK(net, &fl->fl6_src); +out: + dst_hold(&rt->u.dst); + + read_unlock_bh(&table->tb6_lock); + + return rt; +}; + +static struct rt6_info *ip6_route_redirect(struct in6_addr *dest, + struct in6_addr *src, + struct in6_addr *gateway, + struct net_device *dev) +{ + int flags = RT6_LOOKUP_F_HAS_SADDR; + struct net *net = dev_net(dev); + struct ip6rd_flowi rdfl = { + .fl = { + .oif = dev->ifindex, + .nl_u = { + .ip6_u = { + .daddr = *dest, + .saddr = *src, + }, + }, + }, + .gateway = *gateway, + }; + + if (rt6_need_strict(dest)) + flags |= RT6_LOOKUP_F_IFACE; + + return (struct rt6_info *)fib6_rule_lookup(net, (struct flowi *)&rdfl, + flags, __ip6_route_redirect); +} + +void rt6_redirect(struct in6_addr *dest, struct in6_addr *src, + struct in6_addr *saddr, + struct neighbour *neigh, u8 *lladdr, int on_link) +{ + struct rt6_info *rt, *nrt = NULL; + struct netevent_redirect netevent; + struct net *net = dev_net(neigh->dev); + + rt = ip6_route_redirect(dest, src, saddr, neigh->dev); + + if (rt == net->ipv6.ip6_null_entry) { + if (net_ratelimit()) + printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop " + "for redirect target\n"); + goto out; + } + + /* + * We have finally decided to accept it. + */ + + neigh_update(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)) + ); + + /* + * 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(&rt->u.dst); + + /* Duplicate redirect: silently ignore. */ + if (neigh == rt->u.dst.neighbour) + goto out; + + nrt = ip6_rt_copy(rt); + if (nrt == NULL) + goto out; + + nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE; + if (on_link) + nrt->rt6i_flags &= ~RTF_GATEWAY; + + ipv6_addr_copy(&nrt->rt6i_dst.addr, dest); + nrt->rt6i_dst.plen = 128; + nrt->u.dst.flags |= DST_HOST; + + ipv6_addr_copy(&nrt->rt6i_gateway, (struct in6_addr*)neigh->primary_key); + nrt->rt6i_nexthop = neigh_clone(neigh); + /* Reset pmtu, it may be better */ + nrt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(neigh->dev); + nrt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(dev_net(neigh->dev), + dst_mtu(&nrt->u.dst)); + + if (ip6_ins_rt(nrt)) + goto out; + + netevent.old = &rt->u.dst; + netevent.new = &nrt->u.dst; + call_netevent_notifiers(NETEVENT_REDIRECT, &netevent); + + if (rt->rt6i_flags&RTF_CACHE) { + ip6_del_rt(rt); + return; + } + +out: + dst_release(&rt->u.dst); + return; +} + +/* + * Handle ICMP "packet too big" messages + * i.e. Path MTU discovery + */ + +void rt6_pmtu_discovery(struct in6_addr *daddr, struct in6_addr *saddr, + struct net_device *dev, u32 pmtu) +{ + struct rt6_info *rt, *nrt; + struct net *net = dev_net(dev); + int allfrag = 0; + + rt = rt6_lookup(net, daddr, saddr, dev->ifindex, 0); + if (rt == NULL) + return; + + if (pmtu >= dst_mtu(&rt->u.dst)) + goto out; + + if (pmtu < IPV6_MIN_MTU) { + /* + * According to RFC2460, PMTU is set to the IPv6 Minimum Link + * MTU (1280) and a fragment header should always be included + * after a node receiving Too Big message reporting PMTU is + * less than the IPv6 Minimum Link MTU. + */ + pmtu = IPV6_MIN_MTU; + allfrag = 1; + } + + /* New mtu received -> path was valid. + They are sent only in response to data packets, + so that this nexthop apparently is reachable. --ANK + */ + dst_confirm(&rt->u.dst); + + /* Host route. If it is static, it would be better + not to override it, but add new one, so that + when cache entry will expire old pmtu + would return automatically. + */ + if (rt->rt6i_flags & RTF_CACHE) { + rt->u.dst.metrics[RTAX_MTU-1] = pmtu; + if (allfrag) + rt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; + dst_set_expires(&rt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires); + rt->rt6i_flags |= RTF_MODIFIED|RTF_EXPIRES; + goto out; + } + + /* Network route. + Two cases are possible: + 1. It is connected route. Action: COW + 2. It is gatewayed route or NONEXTHOP route. Action: clone it. + */ + if (!rt->rt6i_nexthop && !(rt->rt6i_flags & RTF_NONEXTHOP)) + nrt = rt6_alloc_cow(rt, daddr, saddr); + else + nrt = rt6_alloc_clone(rt, daddr); + + if (nrt) { + nrt->u.dst.metrics[RTAX_MTU-1] = pmtu; + if (allfrag) + nrt->u.dst.metrics[RTAX_FEATURES-1] |= RTAX_FEATURE_ALLFRAG; + + /* According to RFC 1981, detecting PMTU increase shouldn't be + * happened within 5 mins, the recommended timer is 10 mins. + * Here this route expiration time is set to ip6_rt_mtu_expires + * which is 10 mins. After 10 mins the decreased pmtu is expired + * and detecting PMTU increase will be automatically happened. + */ + dst_set_expires(&nrt->u.dst, net->ipv6.sysctl.ip6_rt_mtu_expires); + nrt->rt6i_flags |= RTF_DYNAMIC|RTF_EXPIRES; + + ip6_ins_rt(nrt); + } +out: + dst_release(&rt->u.dst); +} + +/* + * Misc support functions + */ + +static struct rt6_info * ip6_rt_copy(struct rt6_info *ort) +{ + struct net *net = dev_net(ort->rt6i_dev); + struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); + + if (rt) { + rt->u.dst.input = ort->u.dst.input; + rt->u.dst.output = ort->u.dst.output; + + memcpy(rt->u.dst.metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32)); + rt->u.dst.error = ort->u.dst.error; + rt->u.dst.dev = ort->u.dst.dev; + if (rt->u.dst.dev) + dev_hold(rt->u.dst.dev); + rt->rt6i_idev = ort->rt6i_idev; + if (rt->rt6i_idev) + in6_dev_hold(rt->rt6i_idev); + rt->u.dst.lastuse = jiffies; + rt->rt6i_expires = 0; + + ipv6_addr_copy(&rt->rt6i_gateway, &ort->rt6i_gateway); + rt->rt6i_flags = ort->rt6i_flags & ~RTF_EXPIRES; + rt->rt6i_metric = 0; + + 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 + rt->rt6i_table = ort->rt6i_table; + } + return rt; +} + +#ifdef CONFIG_IPV6_ROUTE_INFO +static struct rt6_info *rt6_get_route_info(struct net *net, + struct in6_addr *prefix, int prefixlen, + struct in6_addr *gwaddr, int ifindex) +{ + struct fib6_node *fn; + struct rt6_info *rt = NULL; + struct fib6_table *table; + + table = fib6_get_table(net, RT6_TABLE_INFO); + if (table == NULL) + return NULL; + + write_lock_bh(&table->tb6_lock); + fn = fib6_locate(&table->tb6_root, prefix ,prefixlen, NULL, 0); + if (!fn) + goto out; + + for (rt = fn->leaf; rt; rt = rt->u.dst.rt6_next) { + if (rt->rt6i_dev->ifindex != ifindex) + continue; + if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY)) + continue; + if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr)) + continue; + dst_hold(&rt->u.dst); + break; + } +out: + write_unlock_bh(&table->tb6_lock); + return rt; +} + +static struct rt6_info *rt6_add_route_info(struct net *net, + struct in6_addr *prefix, int prefixlen, + struct in6_addr *gwaddr, int ifindex, + unsigned pref) +{ + struct fib6_config cfg = { + .fc_table = RT6_TABLE_INFO, + .fc_metric = IP6_RT_PRIO_USER, + .fc_ifindex = ifindex, + .fc_dst_len = prefixlen, + .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO | + RTF_UP | RTF_PREF(pref), + .fc_nlinfo.pid = 0, + .fc_nlinfo.nlh = NULL, + .fc_nlinfo.nl_net = net, + }; + + ipv6_addr_copy(&cfg.fc_dst, prefix); + ipv6_addr_copy(&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); + + return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex); +} +#endif + +struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *dev) +{ + struct rt6_info *rt; + struct fib6_table *table; + + table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT); + if (table == NULL) + return NULL; + + write_lock_bh(&table->tb6_lock); + for (rt = table->tb6_root.leaf; rt; rt=rt->u.dst.rt6_next) { + if (dev == rt->rt6i_dev && + ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) && + ipv6_addr_equal(&rt->rt6i_gateway, addr)) + break; + } + if (rt) + dst_hold(&rt->u.dst); + write_unlock_bh(&table->tb6_lock); + return rt; +} + +struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr, + struct net_device *dev, + unsigned int pref) +{ + struct fib6_config cfg = { + .fc_table = RT6_TABLE_DFLT, + .fc_metric = IP6_RT_PRIO_USER, + .fc_ifindex = dev->ifindex, + .fc_flags = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT | + RTF_UP | RTF_EXPIRES | RTF_PREF(pref), + .fc_nlinfo.pid = 0, + .fc_nlinfo.nlh = NULL, + .fc_nlinfo.nl_net = dev_net(dev), + }; + + ipv6_addr_copy(&cfg.fc_gateway, gwaddr); + + ip6_route_add(&cfg); + + return rt6_get_dflt_router(gwaddr, dev); +} + +void rt6_purge_dflt_routers(struct net *net) +{ + struct rt6_info *rt; + struct fib6_table *table; + + /* NOTE: Keep consistent with rt6_get_dflt_router */ + table = fib6_get_table(net, RT6_TABLE_DFLT); + if (table == NULL) + return; + +restart: + read_lock_bh(&table->tb6_lock); + for (rt = table->tb6_root.leaf; rt; rt = rt->u.dst.rt6_next) { + if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) { + dst_hold(&rt->u.dst); + read_unlock_bh(&table->tb6_lock); + ip6_del_rt(rt); + goto restart; + } + } + read_unlock_bh(&table->tb6_lock); +} + +static void rtmsg_to_fib6_config(struct net *net, + struct in6_rtmsg *rtmsg, + struct fib6_config *cfg) +{ + memset(cfg, 0, sizeof(*cfg)); + + cfg->fc_table = RT6_TABLE_MAIN; + cfg->fc_ifindex = rtmsg->rtmsg_ifindex; + cfg->fc_metric = rtmsg->rtmsg_metric; + cfg->fc_expires = rtmsg->rtmsg_info; + cfg->fc_dst_len = rtmsg->rtmsg_dst_len; + cfg->fc_src_len = rtmsg->rtmsg_src_len; + cfg->fc_flags = rtmsg->rtmsg_flags; + + cfg->fc_nlinfo.nl_net = net; + + ipv6_addr_copy(&cfg->fc_dst, &rtmsg->rtmsg_dst); + ipv6_addr_copy(&cfg->fc_src, &rtmsg->rtmsg_src); + ipv6_addr_copy(&cfg->fc_gateway, &rtmsg->rtmsg_gateway); +} + +int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg) +{ + struct fib6_config cfg; + struct in6_rtmsg rtmsg; + int err; + + switch(cmd) { + case SIOCADDRT: /* Add a route */ + case SIOCDELRT: /* Delete a route */ + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + err = copy_from_user(&rtmsg, arg, + sizeof(struct in6_rtmsg)); + if (err) + return -EFAULT; + + rtmsg_to_fib6_config(net, &rtmsg, &cfg); + + rtnl_lock(); + switch (cmd) { + case SIOCADDRT: + err = ip6_route_add(&cfg); + break; + case SIOCDELRT: + err = ip6_route_del(&cfg); + break; + default: + err = -EINVAL; + } + rtnl_unlock(); + + return err; + } + + return -EINVAL; +} + +/* + * Drop the packet on the floor + */ + +static int ip6_pkt_drop(struct sk_buff *skb, int code, int ipstats_mib_noroutes) +{ + int type; + struct dst_entry *dst = skb->dst; + switch (ipstats_mib_noroutes) { + case IPSTATS_MIB_INNOROUTES: + type = ipv6_addr_type(&ipv6_hdr(skb)->daddr); + if (type == IPV6_ADDR_ANY || type == IPV6_ADDR_RESERVED) { + IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), + IPSTATS_MIB_INADDRERRORS); + break; + } + /* FALLTHROUGH */ + case IPSTATS_MIB_OUTNOROUTES: + IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst), + ipstats_mib_noroutes); + break; + } + icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0, skb->dev); + kfree_skb(skb); + 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 sk_buff *skb) +{ + skb->dev = skb->dst->dev; + return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES); +} + +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + +static int ip6_pkt_prohibit(struct sk_buff *skb) +{ + return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES); +} + +static int ip6_pkt_prohibit_out(struct sk_buff *skb) +{ + skb->dev = skb->dst->dev; + return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); +} + +#endif + +/* + * Allocate a dst for local (unicast / anycast) address. + */ + +struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev, + const struct in6_addr *addr, + int anycast) +{ + struct net *net = dev_net(idev->dev); + struct rt6_info *rt = ip6_dst_alloc(net->ipv6.ip6_dst_ops); + + if (rt == NULL) + return ERR_PTR(-ENOMEM); + + dev_hold(net->loopback_dev); + in6_dev_hold(idev); + + rt->u.dst.flags = DST_HOST; + rt->u.dst.input = ip6_input; + rt->u.dst.output = ip6_output; + rt->rt6i_dev = net->loopback_dev; + rt->rt6i_idev = idev; + rt->u.dst.metrics[RTAX_MTU-1] = ipv6_get_mtu(rt->rt6i_dev); + rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, dst_mtu(&rt->u.dst)); + rt->u.dst.metrics[RTAX_HOPLIMIT-1] = -1; + rt->u.dst.obsolete = -1; + + rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP; + if (anycast) + rt->rt6i_flags |= RTF_ANYCAST; + else + rt->rt6i_flags |= RTF_LOCAL; + rt->rt6i_nexthop = ndisc_get_neigh(rt->rt6i_dev, &rt->rt6i_gateway); + if (rt->rt6i_nexthop == NULL) { + dst_free(&rt->u.dst); + return ERR_PTR(-ENOMEM); + } + + ipv6_addr_copy(&rt->rt6i_dst.addr, addr); + rt->rt6i_dst.plen = 128; + rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL); + + atomic_set(&rt->u.dst.__refcnt, 1); + + return rt; +} + +struct arg_dev_net { + struct net_device *dev; + struct net *net; +}; + +static int fib6_ifdown(struct rt6_info *rt, void *arg) +{ + struct net_device *dev = ((struct arg_dev_net *)arg)->dev; + struct net *net = ((struct arg_dev_net *)arg)->net; + + if (((void *)rt->rt6i_dev == dev || dev == NULL) && + rt != net->ipv6.ip6_null_entry) { + RT6_TRACE("deleted by ifdown %p\n", rt); + return -1; + } + return 0; +} + +void rt6_ifdown(struct net *net, struct net_device *dev) +{ + struct arg_dev_net adn = { + .dev = dev, + .net = net, + }; + + fib6_clean_all(net, fib6_ifdown, 0, &adn); + icmp6_clean_all(fib6_ifdown, &adn); +} + +struct rt6_mtu_change_arg +{ + struct net_device *dev; + unsigned mtu; +}; + +static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg) +{ + struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg; + struct inet6_dev *idev; + struct net *net = dev_net(arg->dev); + + /* 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 == NULL) + return 0; + + /* For administrative MTU increase, there is no way to discover + IPv6 PMTU increase, so PMTU increase should be updated here. + Since RFC 1981 doesn't include administrative MTU increase + update PMTU increase is a MUST. (i.e. jumbo frame) + */ + /* + If new MTU is less than route PMTU, this new MTU will be the + lowest MTU in the path, update the route PMTU to reflect PMTU + decreases; if new MTU is greater than route PMTU, and the + old MTU is the lowest MTU in the path, update the route PMTU + to reflect the increase. In this case if the other nodes' MTU + also have the lowest MTU, TOO BIG MESSAGE will be lead to + PMTU discouvery. + */ + if (rt->rt6i_dev == arg->dev && + !dst_metric_locked(&rt->u.dst, RTAX_MTU) && + (dst_mtu(&rt->u.dst) >= arg->mtu || + (dst_mtu(&rt->u.dst) < arg->mtu && + dst_mtu(&rt->u.dst) == idev->cnf.mtu6))) { + rt->u.dst.metrics[RTAX_MTU-1] = arg->mtu; + rt->u.dst.metrics[RTAX_ADVMSS-1] = ipv6_advmss(net, arg->mtu); + } + return 0; +} + +void rt6_mtu_change(struct net_device *dev, unsigned mtu) +{ + struct rt6_mtu_change_arg arg = { + .dev = dev, + .mtu = mtu, + }; + + fib6_clean_all(dev_net(dev), rt6_mtu_change_route, 0, &arg); +} + +static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = { + [RTA_GATEWAY] = { .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 }, +}; + +static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh, + struct fib6_config *cfg) +{ + struct rtmsg *rtm; + struct nlattr *tb[RTA_MAX+1]; + int err; + + err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); + if (err < 0) + goto errout; + + err = -EINVAL; + rtm = nlmsg_data(nlh); + memset(cfg, 0, sizeof(*cfg)); + + cfg->fc_table = rtm->rtm_table; + cfg->fc_dst_len = rtm->rtm_dst_len; + cfg->fc_src_len = rtm->rtm_src_len; + cfg->fc_flags = RTF_UP; + cfg->fc_protocol = rtm->rtm_protocol; + + if (rtm->rtm_type == RTN_UNREACHABLE) + cfg->fc_flags |= RTF_REJECT; + + cfg->fc_nlinfo.pid = NETLINK_CB(skb).pid; + cfg->fc_nlinfo.nlh = nlh; + cfg->fc_nlinfo.nl_net = sock_net(skb->sk); + + if (tb[RTA_GATEWAY]) { + nla_memcpy(&cfg->fc_gateway, tb[RTA_GATEWAY], 16); + cfg->fc_flags |= RTF_GATEWAY; + } + + 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_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]); + + err = 0; +errout: + return err; +} + +static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) +{ + struct fib6_config cfg; + int err; + + err = rtm_to_fib6_config(skb, nlh, &cfg); + if (err < 0) + return err; + + return ip6_route_del(&cfg); +} + +static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) +{ + struct fib6_config cfg; + int err; + + err = rtm_to_fib6_config(skb, nlh, &cfg); + if (err < 0) + return err; + + return ip6_route_add(&cfg); +} + +static inline size_t rt6_nlmsg_size(void) +{ + 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)); +} + +static int rt6_fill_node(struct net *net, + struct sk_buff *skb, struct rt6_info *rt, + struct in6_addr *dst, struct in6_addr *src, + int iif, int type, u32 pid, u32 seq, + int prefix, int nowait, unsigned int flags) +{ + struct rtmsg *rtm; + struct nlmsghdr *nlh; + long expires; + u32 table; + + if (prefix) { /* user wants prefix routes only */ + if (!(rt->rt6i_flags & RTF_PREFIX_RT)) { + /* success since this is not a prefix route */ + return 1; + } + } + + nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtm), flags); + if (nlh == NULL) + return -EMSGSIZE; + + rtm = nlmsg_data(nlh); + rtm->rtm_family = AF_INET6; + rtm->rtm_dst_len = rt->rt6i_dst.plen; + rtm->rtm_src_len = rt->rt6i_src.plen; + rtm->rtm_tos = 0; + if (rt->rt6i_table) + table = rt->rt6i_table->tb6_id; + else + table = RT6_TABLE_UNSPEC; + rtm->rtm_table = table; + NLA_PUT_U32(skb, RTA_TABLE, table); + if (rt->rt6i_flags&RTF_REJECT) + rtm->rtm_type = RTN_UNREACHABLE; + else if (rt->rt6i_dev && (rt->rt6i_dev->flags&IFF_LOOPBACK)) + rtm->rtm_type = RTN_LOCAL; + else + rtm->rtm_type = RTN_UNICAST; + rtm->rtm_flags = 0; + rtm->rtm_scope = RT_SCOPE_UNIVERSE; + rtm->rtm_protocol = rt->rt6i_protocol; + if (rt->rt6i_flags&RTF_DYNAMIC) + rtm->rtm_protocol = RTPROT_REDIRECT; + else if (rt->rt6i_flags & RTF_ADDRCONF) + rtm->rtm_protocol = RTPROT_KERNEL; + else if (rt->rt6i_flags&RTF_DEFAULT) + rtm->rtm_protocol = RTPROT_RA; + + if (rt->rt6i_flags&RTF_CACHE) + rtm->rtm_flags |= RTM_F_CLONED; + + if (dst) { + NLA_PUT(skb, RTA_DST, 16, dst); + rtm->rtm_dst_len = 128; + } else if (rtm->rtm_dst_len) + NLA_PUT(skb, RTA_DST, 16, &rt->rt6i_dst.addr); +#ifdef CONFIG_IPV6_SUBTREES + if (src) { + NLA_PUT(skb, RTA_SRC, 16, src); + rtm->rtm_src_len = 128; + } else if (rtm->rtm_src_len) + NLA_PUT(skb, RTA_SRC, 16, &rt->rt6i_src.addr); +#endif + if (iif) { +#ifdef CONFIG_IPV6_MROUTE + if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) { + int err = ip6mr_get_route(skb, rtm, nowait); + if (err <= 0) { + if (!nowait) { + if (err == 0) + return 0; + goto nla_put_failure; + } else { + if (err == -EMSGSIZE) + goto nla_put_failure; + } + } + } else +#endif + NLA_PUT_U32(skb, RTA_IIF, iif); + } else if (dst) { + struct inet6_dev *idev = ip6_dst_idev(&rt->u.dst); + struct in6_addr saddr_buf; + if (ipv6_dev_get_saddr(net, idev ? idev->dev : NULL, + dst, 0, &saddr_buf) == 0) + NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf); + } + + if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0) + goto nla_put_failure; + + if (rt->u.dst.neighbour) + NLA_PUT(skb, RTA_GATEWAY, 16, &rt->u.dst.neighbour->primary_key); + + if (rt->u.dst.dev) + NLA_PUT_U32(skb, RTA_OIF, rt->rt6i_dev->ifindex); + + NLA_PUT_U32(skb, RTA_PRIORITY, rt->rt6i_metric); + + if (!(rt->rt6i_flags & RTF_EXPIRES)) + expires = 0; + else if (rt->rt6i_expires - jiffies < INT_MAX) + expires = rt->rt6i_expires - jiffies; + else + expires = INT_MAX; + + if (rtnl_put_cacheinfo(skb, &rt->u.dst, 0, 0, 0, + expires, rt->u.dst.error) < 0) + goto nla_put_failure; + + return nlmsg_end(skb, nlh); + +nla_put_failure: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +int rt6_dump_route(struct rt6_info *rt, void *p_arg) +{ + struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg; + int prefix; + + if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) { + struct rtmsg *rtm = nlmsg_data(arg->cb->nlh); + prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0; + } else + prefix = 0; + + return rt6_fill_node(arg->net, + arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE, + NETLINK_CB(arg->cb->skb).pid, arg->cb->nlh->nlmsg_seq, + prefix, 0, NLM_F_MULTI); +} + +static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) +{ + struct net *net = sock_net(in_skb->sk); + struct nlattr *tb[RTA_MAX+1]; + struct rt6_info *rt; + struct sk_buff *skb; + struct rtmsg *rtm; + struct flowi fl; + int err, iif = 0; + + err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy); + if (err < 0) + goto errout; + + err = -EINVAL; + memset(&fl, 0, sizeof(fl)); + + if (tb[RTA_SRC]) { + if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr)) + goto errout; + + ipv6_addr_copy(&fl.fl6_src, nla_data(tb[RTA_SRC])); + } + + if (tb[RTA_DST]) { + if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr)) + goto errout; + + ipv6_addr_copy(&fl.fl6_dst, nla_data(tb[RTA_DST])); + } + + if (tb[RTA_IIF]) + iif = nla_get_u32(tb[RTA_IIF]); + + if (tb[RTA_OIF]) + fl.oif = nla_get_u32(tb[RTA_OIF]); + + if (iif) { + struct net_device *dev; + dev = __dev_get_by_index(net, iif); + if (!dev) { + err = -ENODEV; + goto errout; + } + } + + skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); + if (skb == NULL) { + err = -ENOBUFS; + goto errout; + } + + /* Reserve room for dummy headers, this skb can pass + through good chunk of routing engine. + */ + skb_reset_mac_header(skb); + skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr)); + + rt = (struct rt6_info*) ip6_route_output(net, NULL, &fl); + skb->dst = &rt->u.dst; + + err = rt6_fill_node(net, skb, rt, &fl.fl6_dst, &fl.fl6_src, iif, + RTM_NEWROUTE, NETLINK_CB(in_skb).pid, + nlh->nlmsg_seq, 0, 0, 0); + if (err < 0) { + kfree_skb(skb); + goto errout; + } + + err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); +errout: + return err; +} + +void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info) +{ + struct sk_buff *skb; + struct net *net = info->nl_net; + u32 seq; + int err; + + err = -ENOBUFS; + seq = info->nlh != NULL ? info->nlh->nlmsg_seq : 0; + + skb = nlmsg_new(rt6_nlmsg_size(), gfp_any()); + if (skb == NULL) + goto errout; + + err = rt6_fill_node(net, skb, rt, NULL, NULL, 0, + event, info->pid, seq, 0, 0, 0); + if (err < 0) { + /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(skb); + goto errout; + } + err = rtnl_notify(skb, net, info->pid, RTNLGRP_IPV6_ROUTE, + info->nlh, gfp_any()); +errout: + if (err < 0) + rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err); +} + +static int ip6_route_dev_notify(struct notifier_block *this, + unsigned long event, void *data) +{ + struct net_device *dev = (struct net_device *)data; + struct net *net = dev_net(dev); + + if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) { + net->ipv6.ip6_null_entry->u.dst.dev = dev; + net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev); +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + net->ipv6.ip6_prohibit_entry->u.dst.dev = dev; + net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev); + net->ipv6.ip6_blk_hole_entry->u.dst.dev = dev; + net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); +#endif + } + + return NOTIFY_OK; +} + +/* + * /proc + */ + +#ifdef CONFIG_PROC_FS + +#define RT6_INFO_LEN (32 + 4 + 32 + 4 + 32 + 40 + 5 + 1) + +struct rt6_proc_arg +{ + char *buffer; + int offset; + int length; + int skip; + int len; +}; + +static int rt6_info_route(struct rt6_info *rt, void *p_arg) +{ + struct seq_file *m = p_arg; + + seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_dst.addr), + rt->rt6i_dst.plen); + +#ifdef CONFIG_IPV6_SUBTREES + seq_printf(m, NIP6_SEQFMT " %02x ", NIP6(rt->rt6i_src.addr), + rt->rt6i_src.plen); +#else + seq_puts(m, "00000000000000000000000000000000 00 "); +#endif + + if (rt->rt6i_nexthop) { + seq_printf(m, NIP6_SEQFMT, + NIP6(*((struct in6_addr *)rt->rt6i_nexthop->primary_key))); + } else { + seq_puts(m, "00000000000000000000000000000000"); + } + seq_printf(m, " %08x %08x %08x %08x %8s\n", + rt->rt6i_metric, atomic_read(&rt->u.dst.__refcnt), + rt->u.dst.__use, rt->rt6i_flags, + rt->rt6i_dev ? rt->rt6i_dev->name : ""); + return 0; +} + +static int ipv6_route_show(struct seq_file *m, void *v) +{ + struct net *net = (struct net *)m->private; + fib6_clean_all(net, rt6_info_route, 0, m); + return 0; +} + +static int ipv6_route_open(struct inode *inode, struct file *file) +{ + return single_open_net(inode, file, ipv6_route_show); +} + +static const struct file_operations ipv6_route_proc_fops = { + .owner = THIS_MODULE, + .open = ipv6_route_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release_net, +}; + +static int rt6_stats_seq_show(struct seq_file *seq, void *v) +{ + struct net *net = (struct net *)seq->private; + seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n", + net->ipv6.rt6_stats->fib_nodes, + net->ipv6.rt6_stats->fib_route_nodes, + net->ipv6.rt6_stats->fib_rt_alloc, + net->ipv6.rt6_stats->fib_rt_entries, + net->ipv6.rt6_stats->fib_rt_cache, + atomic_read(&net->ipv6.ip6_dst_ops->entries), + net->ipv6.rt6_stats->fib_discarded_routes); + + return 0; +} + +static int rt6_stats_seq_open(struct inode *inode, struct file *file) +{ + return single_open_net(inode, file, rt6_stats_seq_show); +} + +static const struct file_operations rt6_stats_seq_fops = { + .owner = THIS_MODULE, + .open = rt6_stats_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release_net, +}; +#endif /* CONFIG_PROC_FS */ + +#ifdef CONFIG_SYSCTL + +static +int ipv6_sysctl_rtcache_flush(ctl_table *ctl, int write, struct file * filp, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct net *net = current->nsproxy->net_ns; + int delay = net->ipv6.sysctl.flush_delay; + if (write) { + proc_dointvec(ctl, write, filp, buffer, lenp, ppos); + fib6_run_gc(delay <= 0 ? ~0UL : (unsigned long)delay, net); + return 0; + } else + return -EINVAL; +} + +ctl_table ipv6_route_table_template[] = { + { + .procname = "flush", + .data = &init_net.ipv6.sysctl.flush_delay, + .maxlen = sizeof(int), + .mode = 0200, + .proc_handler = &ipv6_sysctl_rtcache_flush + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_THRESH, + .procname = "gc_thresh", + .data = &ip6_dst_ops_template.gc_thresh, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_IPV6_ROUTE_MAX_SIZE, + .procname = "max_size", + .data = &init_net.ipv6.sysctl.ip6_rt_max_size, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL, + .procname = "gc_min_interval", + .data = &init_net.ipv6.sysctl.ip6_rt_gc_min_interval, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_TIMEOUT, + .procname = "gc_timeout", + .data = &init_net.ipv6.sysctl.ip6_rt_gc_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_INTERVAL, + .procname = "gc_interval", + .data = &init_net.ipv6.sysctl.ip6_rt_gc_interval, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_ELASTICITY, + .procname = "gc_elasticity", + .data = &init_net.ipv6.sysctl.ip6_rt_gc_elasticity, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_MTU_EXPIRES, + .procname = "mtu_expires", + .data = &init_net.ipv6.sysctl.ip6_rt_mtu_expires, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_MIN_ADVMSS, + .procname = "min_adv_mss", + .data = &init_net.ipv6.sysctl.ip6_rt_min_advmss, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + .strategy = &sysctl_jiffies, + }, + { + .ctl_name = NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS, + .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, + .strategy = &sysctl_ms_jiffies, + }, + { .ctl_name = 0 } +}; + +struct ctl_table *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.flush_delay; + table[1].data = &net->ipv6.ip6_dst_ops->gc_thresh; + table[2].data = &net->ipv6.sysctl.ip6_rt_max_size; + 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; + } + + return table; +} +#endif + +static int ip6_route_net_init(struct net *net) +{ + int ret = -ENOMEM; + + net->ipv6.ip6_dst_ops = kmemdup(&ip6_dst_ops_template, + sizeof(*net->ipv6.ip6_dst_ops), + GFP_KERNEL); + if (!net->ipv6.ip6_dst_ops) + goto out; + net->ipv6.ip6_dst_ops->dst_net = hold_net(net); + + net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template, + sizeof(*net->ipv6.ip6_null_entry), + GFP_KERNEL); + if (!net->ipv6.ip6_null_entry) + goto out_ip6_dst_ops; + net->ipv6.ip6_null_entry->u.dst.path = + (struct dst_entry *)net->ipv6.ip6_null_entry; + net->ipv6.ip6_null_entry->u.dst.ops = net->ipv6.ip6_dst_ops; + +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + 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->u.dst.path = + (struct dst_entry *)net->ipv6.ip6_prohibit_entry; + net->ipv6.ip6_prohibit_entry->u.dst.ops = net->ipv6.ip6_dst_ops; + + 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->u.dst.path = + (struct dst_entry *)net->ipv6.ip6_blk_hole_entry; + net->ipv6.ip6_blk_hole_entry->u.dst.ops = net->ipv6.ip6_dst_ops; +#endif + + net->ipv6.sysctl.flush_delay = 0; + net->ipv6.sysctl.ip6_rt_max_size = 4096; + 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; + +#ifdef CONFIG_PROC_FS + proc_net_fops_create(net, "ipv6_route", 0, &ipv6_route_proc_fops); + proc_net_fops_create(net, "rt6_stats", S_IRUGO, &rt6_stats_seq_fops); +#endif + 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_ip6_dst_ops: + release_net(net->ipv6.ip6_dst_ops->dst_net); + kfree(net->ipv6.ip6_dst_ops); + goto out; +} + +static void ip6_route_net_exit(struct net *net) +{ +#ifdef CONFIG_PROC_FS + proc_net_remove(net, "ipv6_route"); + proc_net_remove(net, "rt6_stats"); +#endif + 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 + release_net(net->ipv6.ip6_dst_ops->dst_net); + kfree(net->ipv6.ip6_dst_ops); +} + +static struct pernet_operations ip6_route_net_ops = { + .init = ip6_route_net_init, + .exit = ip6_route_net_exit, +}; + +static struct notifier_block ip6_route_dev_notifier = { + .notifier_call = ip6_route_dev_notify, + .priority = 0, +}; + +int __init ip6_route_init(void) +{ + int ret; + + ret = -ENOMEM; + ip6_dst_ops_template.kmem_cachep = + kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0, + SLAB_HWCACHE_ALIGN, NULL); + if (!ip6_dst_ops_template.kmem_cachep) + goto out;; + + ret = register_pernet_subsys(&ip6_route_net_ops); + if (ret) + goto out_kmem_cache; + + ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep; + + /* Registering of the loopback is done before this portion of code, + * the loopback reference in rt6_info will not be taken, do it + * manually for init_net */ + init_net.ipv6.ip6_null_entry->u.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->u.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->u.dst.dev = init_net.loopback_dev; + init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); + #endif + ret = fib6_init(); + if (ret) + goto out_register_subsys; + + ret = xfrm6_init(); + if (ret) + goto out_fib6_init; + + ret = fib6_rules_init(); + if (ret) + goto xfrm6_init; + + ret = -ENOBUFS; + if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) || + __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) || + __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL)) + goto fib6_rules_init; + + ret = register_netdevice_notifier(&ip6_route_dev_notifier); + if (ret) + goto fib6_rules_init; + +out: + return ret; + +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_kmem_cache: + kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); + goto out; +} + +void ip6_route_cleanup(void) +{ + unregister_netdevice_notifier(&ip6_route_dev_notifier); + fib6_rules_cleanup(); + xfrm6_fini(); + fib6_gc_cleanup(); + unregister_pernet_subsys(&ip6_route_net_ops); + kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep); +} |
