File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
new file mode 100644
index 0000000..84afb9a
--- /dev/null
+++ b/net/ipv6/ndisc.c
@@ -0,0 +1,1853 @@
+/*
+ * Neighbour Discovery for IPv6
+ * Linux INET6 implementation
+ *
+ * Authors:
+ * Pedro Roque <roque@di.fc.ul.pt>
+ * Mike Shaver <shaver@ingenia.com>
+ *
+ * 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:
+ *
+ * Alexey I. Froloff : RFC6106 (DNSSL) support
+ * Pierre Ynard : export userland ND options
+ * through netlink (RDNSS support)
+ * Lars Fenneberg : fixed MTU setting on receipt
+ * of an RA.
+ * Janos Farkas : kmalloc failure checks
+ * Alexey Kuznetsov : state machine reworked
+ * and moved to net/core.
+ * Pekka Savola : RFC2461 validation
+ * YOSHIFUJI Hideaki @USAGI : Verify ND options properly
+ */
+
+#define pr_fmt(fmt) "ICMPv6: " fmt
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/sched.h>
+#include <linux/net.h>
+#include <linux/in6.h>
+#include <linux/route.h>
+#include <linux/init.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+
+#include <linux/if_addr.h>
+#include <linux/if_arp.h>
+#include <linux/ipv6.h>
+#include <linux/icmpv6.h>
+#include <linux/jhash.h>
+
+#include <net/sock.h>
+#include <net/snmp.h>
+
+#include <net/ipv6.h>
+#include <net/protocol.h>
+#include <net/ndisc.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
+#include <net/icmp.h>
+
+#include <net/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include <net/flow.h>
+#include <net/ip6_checksum.h>
+#include <net/inet_common.h>
+#include <net/l3mdev.h>
+#include <linux/proc_fs.h>
+
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+
+/* Set to 3 to get tracing... */
+#define ND_DEBUG 1
+
+#define ND_PRINTK(val, level, fmt, ...) \
+do { \
+ if (val <= ND_DEBUG) \
+ net_##level##_ratelimited(fmt, ##__VA_ARGS__); \
+} while (0)
+
+static u32 ndisc_hash(const void *pkey,
+ const struct net_device *dev,
+ __u32 *hash_rnd);
+static bool ndisc_key_eq(const struct neighbour *neigh, const void *pkey);
+static int ndisc_constructor(struct neighbour *neigh);
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb);
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb);
+static int pndisc_constructor(struct pneigh_entry *n);
+static void pndisc_destructor(struct pneigh_entry *n);
+static void pndisc_redo(struct sk_buff *skb);
+
+static const struct neigh_ops ndisc_generic_ops = {
+ .family = AF_INET6,
+ .solicit = ndisc_solicit,
+ .error_report = ndisc_error_report,
+ .output = neigh_resolve_output,
+ .connected_output = neigh_connected_output,
+};
+
+static const struct neigh_ops ndisc_hh_ops = {
+ .family = AF_INET6,
+ .solicit = ndisc_solicit,
+ .error_report = ndisc_error_report,
+ .output = neigh_resolve_output,
+ .connected_output = neigh_resolve_output,
+};
+
+
+static const struct neigh_ops ndisc_direct_ops = {
+ .family = AF_INET6,
+ .output = neigh_direct_output,
+ .connected_output = neigh_direct_output,
+};
+
+struct neigh_table nd_tbl = {
+ .family = AF_INET6,
+ .key_len = sizeof(struct in6_addr),
+ .protocol = cpu_to_be16(ETH_P_IPV6),
+ .hash = ndisc_hash,
+ .key_eq = ndisc_key_eq,
+ .constructor = ndisc_constructor,
+ .pconstructor = pndisc_constructor,
+ .pdestructor = pndisc_destructor,
+ .proxy_redo = pndisc_redo,
+ .id = "ndisc_cache",
+ .parms = {
+ .tbl = &nd_tbl,
+ .reachable_time = ND_REACHABLE_TIME,
+ .data = {
+ [NEIGH_VAR_MCAST_PROBES] = 3,
+ [NEIGH_VAR_UCAST_PROBES] = 3,
+ [NEIGH_VAR_RETRANS_TIME] = ND_RETRANS_TIMER,
+ [NEIGH_VAR_BASE_REACHABLE_TIME] = ND_REACHABLE_TIME,
+ [NEIGH_VAR_DELAY_PROBE_TIME] = 5 * HZ,
+ [NEIGH_VAR_GC_STALETIME] = 60 * HZ,
+ [NEIGH_VAR_QUEUE_LEN_BYTES] = 64 * 1024,
+ [NEIGH_VAR_PROXY_QLEN] = 64,
+ [NEIGH_VAR_ANYCAST_DELAY] = 1 * HZ,
+ [NEIGH_VAR_PROXY_DELAY] = (8 * HZ) / 10,
+ },
+ },
+ .gc_interval = 30 * HZ,
+ .gc_thresh1 = 128,
+ .gc_thresh2 = 512,
+ .gc_thresh3 = 1024,
+};
+EXPORT_SYMBOL_GPL(nd_tbl);
+
+static void ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data)
+{
+ int pad = ndisc_addr_option_pad(skb->dev->type);
+ int data_len = skb->dev->addr_len;
+ int space = ndisc_opt_addr_space(skb->dev);
+ u8 *opt = skb_put(skb, space);
+
+ opt[0] = type;
+ opt[1] = space>>3;
+
+ memset(opt + 2, 0, pad);
+ opt += pad;
+ space -= pad;
+
+ memcpy(opt+2, data, data_len);
+ data_len += 2;
+ opt += data_len;
+ space -= data_len;
+ if (space > 0)
+ memset(opt, 0, space);
+}
+
+static struct nd_opt_hdr *ndisc_next_option(struct nd_opt_hdr *cur,
+ struct nd_opt_hdr *end)
+{
+ int type;
+ if (!cur || !end || cur >= end)
+ return NULL;
+ type = cur->nd_opt_type;
+ do {
+ cur = ((void *)cur) + (cur->nd_opt_len << 3);
+ } while (cur < end && cur->nd_opt_type != type);
+ return cur <= end && cur->nd_opt_type == type ? cur : NULL;
+}
+
+static inline int ndisc_is_useropt(struct nd_opt_hdr *opt)
+{
+ return opt->nd_opt_type == ND_OPT_RDNSS ||
+ opt->nd_opt_type == ND_OPT_DNSSL;
+}
+
+static struct nd_opt_hdr *ndisc_next_useropt(struct nd_opt_hdr *cur,
+ struct nd_opt_hdr *end)
+{
+ if (!cur || !end || cur >= end)
+ return NULL;
+ do {
+ cur = ((void *)cur) + (cur->nd_opt_len << 3);
+ } while (cur < end && !ndisc_is_useropt(cur));
+ return cur <= end && ndisc_is_useropt(cur) ? cur : NULL;
+}
+
+struct ndisc_options *ndisc_parse_options(u8 *opt, int opt_len,
+ struct ndisc_options *ndopts)
+{
+ struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)opt;
+
+ if (!nd_opt || opt_len < 0 || !ndopts)
+ return NULL;
+ memset(ndopts, 0, sizeof(*ndopts));
+ while (opt_len) {
+ int l;
+ if (opt_len < sizeof(struct nd_opt_hdr))
+ return NULL;
+ l = nd_opt->nd_opt_len << 3;
+ if (opt_len < l || l == 0)
+ return NULL;
+ switch (nd_opt->nd_opt_type) {
+ case ND_OPT_SOURCE_LL_ADDR:
+ case ND_OPT_TARGET_LL_ADDR:
+ case ND_OPT_MTU:
+ case ND_OPT_REDIRECT_HDR:
+ if (ndopts->nd_opt_array[nd_opt->nd_opt_type]) {
+ ND_PRINTK(2, warn,
+ "%s: duplicated ND6 option found: type=%d\n",
+ __func__, nd_opt->nd_opt_type);
+ } else {
+ ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
+ }
+ break;
+ case ND_OPT_PREFIX_INFO:
+ ndopts->nd_opts_pi_end = nd_opt;
+ if (!ndopts->nd_opt_array[nd_opt->nd_opt_type])
+ ndopts->nd_opt_array[nd_opt->nd_opt_type] = nd_opt;
+ break;
+#ifdef CONFIG_IPV6_ROUTE_INFO
+ case ND_OPT_ROUTE_INFO:
+ ndopts->nd_opts_ri_end = nd_opt;
+ if (!ndopts->nd_opts_ri)
+ ndopts->nd_opts_ri = nd_opt;
+ break;
+#endif
+ default:
+ if (ndisc_is_useropt(nd_opt)) {
+ ndopts->nd_useropts_end = nd_opt;
+ if (!ndopts->nd_useropts)
+ ndopts->nd_useropts = nd_opt;
+ } else {
+ /*
+ * Unknown options must be silently ignored,
+ * to accommodate future extension to the
+ * protocol.
+ */
+ ND_PRINTK(2, notice,
+ "%s: ignored unsupported option; type=%d, len=%d\n",
+ __func__,
+ nd_opt->nd_opt_type,
+ nd_opt->nd_opt_len);
+ }
+ }
+ opt_len -= l;
+ nd_opt = ((void *)nd_opt) + l;
+ }
+ return ndopts;
+}
+
+int ndisc_mc_map(const struct in6_addr *addr, char *buf, struct net_device *dev, int dir)
+{
+ switch (dev->type) {
+ case ARPHRD_ETHER:
+ case ARPHRD_IEEE802: /* Not sure. Check it later. --ANK */
+ case ARPHRD_FDDI:
+ ipv6_eth_mc_map(addr, buf);
+ return 0;
+ case ARPHRD_ARCNET:
+ ipv6_arcnet_mc_map(addr, buf);
+ return 0;
+ case ARPHRD_INFINIBAND:
+ ipv6_ib_mc_map(addr, dev->broadcast, buf);
+ return 0;
+ case ARPHRD_IPGRE:
+ return ipv6_ipgre_mc_map(addr, dev->broadcast, buf);
+ default:
+ if (dir) {
+ memcpy(buf, dev->broadcast, dev->addr_len);
+ return 0;
+ }
+ }
+ return -EINVAL;
+}
+EXPORT_SYMBOL(ndisc_mc_map);
+
+static u32 ndisc_hash(const void *pkey,
+ const struct net_device *dev,
+ __u32 *hash_rnd)
+{
+ return ndisc_hashfn(pkey, dev, hash_rnd);
+}
+
+static bool ndisc_key_eq(const struct neighbour *n, const void *pkey)
+{
+ return neigh_key_eq128(n, pkey);
+}
+
+static int ndisc_constructor(struct neighbour *neigh)
+{
+ struct in6_addr *addr = (struct in6_addr *)&neigh->primary_key;
+ struct net_device *dev = neigh->dev;
+ struct inet6_dev *in6_dev;
+ struct neigh_parms *parms;
+ bool is_multicast = ipv6_addr_is_multicast(addr);
+
+ in6_dev = in6_dev_get(dev);
+ if (!in6_dev) {
+ return -EINVAL;
+ }
+
+ parms = in6_dev->nd_parms;
+ __neigh_parms_put(neigh->parms);
+ neigh->parms = neigh_parms_clone(parms);
+
+ neigh->type = is_multicast ? RTN_MULTICAST : RTN_UNICAST;
+ if (!dev->header_ops) {
+ neigh->nud_state = NUD_NOARP;
+ neigh->ops = &ndisc_direct_ops;
+ neigh->output = neigh_direct_output;
+ } else {
+ if (is_multicast) {
+ neigh->nud_state = NUD_NOARP;
+ ndisc_mc_map(addr, neigh->ha, dev, 1);
+ } else if (dev->flags&(IFF_NOARP|IFF_LOOPBACK)) {
+ neigh->nud_state = NUD_NOARP;
+ memcpy(neigh->ha, dev->dev_addr, dev->addr_len);
+ if (dev->flags&IFF_LOOPBACK)
+ neigh->type = RTN_LOCAL;
+ } else if (dev->flags&IFF_POINTOPOINT) {
+ neigh->nud_state = NUD_NOARP;
+ memcpy(neigh->ha, dev->broadcast, dev->addr_len);
+ }
+ if (dev->header_ops->cache)
+ neigh->ops = &ndisc_hh_ops;
+ else
+ neigh->ops = &ndisc_generic_ops;
+ if (neigh->nud_state&NUD_VALID)
+ neigh->output = neigh->ops->connected_output;
+ else
+ neigh->output = neigh->ops->output;
+ }
+ in6_dev_put(in6_dev);
+ return 0;
+}
+
+static int pndisc_constructor(struct pneigh_entry *n)
+{
+ struct in6_addr *addr = (struct in6_addr *)&n->key;
+ struct in6_addr maddr;
+ struct net_device *dev = n->dev;
+
+ if (!dev || !__in6_dev_get(dev))
+ return -EINVAL;
+ addrconf_addr_solict_mult(addr, &maddr);
+ ipv6_dev_mc_inc(dev, &maddr);
+ return 0;
+}
+
+static void pndisc_destructor(struct pneigh_entry *n)
+{
+ struct in6_addr *addr = (struct in6_addr *)&n->key;
+ struct in6_addr maddr;
+ struct net_device *dev = n->dev;
+
+ if (!dev || !__in6_dev_get(dev))
+ return;
+ addrconf_addr_solict_mult(addr, &maddr);
+ ipv6_dev_mc_dec(dev, &maddr);
+}
+
+static struct sk_buff *ndisc_alloc_skb(struct net_device *dev,
+ int len)
+{
+ int hlen = LL_RESERVED_SPACE(dev);
+ int tlen = dev->needed_tailroom;
+ struct sock *sk = dev_net(dev)->ipv6.ndisc_sk;
+ struct sk_buff *skb;
+
+ skb = alloc_skb(hlen + sizeof(struct ipv6hdr) + len + tlen, GFP_ATOMIC);
+ if (!skb) {
+ ND_PRINTK(0, err, "ndisc: %s failed to allocate an skb\n",
+ __func__);
+ return NULL;
+ }
+
+ skb->protocol = htons(ETH_P_IPV6);
+ skb->dev = dev;
+
+ skb_reserve(skb, hlen + sizeof(struct ipv6hdr));
+ skb_reset_transport_header(skb);
+
+ /* Manually assign socket ownership as we avoid calling
+ * sock_alloc_send_pskb() to bypass wmem buffer limits
+ */
+ skb_set_owner_w(skb, sk);
+
+ return skb;
+}
+
+static void ip6_nd_hdr(struct sk_buff *skb,
+ const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ int hop_limit, int len)
+{
+ struct ipv6hdr *hdr;
+
+ skb_push(skb, sizeof(*hdr));
+ skb_reset_network_header(skb);
+ hdr = ipv6_hdr(skb);
+
+ ip6_flow_hdr(hdr, 0, 0);
+
+ hdr->payload_len = htons(len);
+ hdr->nexthdr = IPPROTO_ICMPV6;
+ hdr->hop_limit = hop_limit;
+
+ hdr->saddr = *saddr;
+ hdr->daddr = *daddr;
+}
+
+static void ndisc_send_skb(struct sk_buff *skb,
+ const struct in6_addr *daddr,
+ const struct in6_addr *saddr)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct net *net = dev_net(skb->dev);
+ struct sock *sk = net->ipv6.ndisc_sk;
+ struct inet6_dev *idev;
+ int err;
+ struct icmp6hdr *icmp6h = icmp6_hdr(skb);
+ u8 type;
+
+ type = icmp6h->icmp6_type;
+
+ if (!dst) {
+ struct flowi6 fl6;
+ int oif = l3mdev_fib_oif(skb->dev);
+
+ icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
+ if (oif != skb->dev->ifindex)
+ fl6.flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
+ dst = icmp6_dst_alloc(skb->dev, &fl6);
+ if (IS_ERR(dst)) {
+ kfree_skb(skb);
+ return;
+ }
+
+ skb_dst_set(skb, dst);
+ }
+
+ icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, skb->len,
+ IPPROTO_ICMPV6,
+ csum_partial(icmp6h,
+ skb->len, 0));
+
+ ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len);
+
+ rcu_read_lock();
+ idev = __in6_dev_get(dst->dev);
+ IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
+
+ err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
+ net, sk, skb, NULL, dst->dev,
+ dst_output);
+ if (!err) {
+ ICMP6MSGOUT_INC_STATS(net, idev, type);
+ ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
+ }
+
+ rcu_read_unlock();
+}
+
+void ndisc_send_na(struct net_device *dev, const struct in6_addr *daddr,
+ const struct in6_addr *solicited_addr,
+ bool router, bool solicited, bool override, bool inc_opt)
+{
+ struct sk_buff *skb;
+ struct in6_addr tmpaddr;
+ struct inet6_ifaddr *ifp;
+ const struct in6_addr *src_addr;
+ struct nd_msg *msg;
+ int optlen = 0;
+
+ /* for anycast or proxy, solicited_addr != src_addr */
+ ifp = ipv6_get_ifaddr(dev_net(dev), solicited_addr, dev, 1);
+ if (ifp) {
+ src_addr = solicited_addr;
+ if (ifp->flags & IFA_F_OPTIMISTIC)
+ override = false;
+ inc_opt |= ifp->idev->cnf.force_tllao;
+ in6_ifa_put(ifp);
+ } else {
+ if (ipv6_dev_get_saddr(dev_net(dev), dev, daddr,
+ inet6_sk(dev_net(dev)->ipv6.ndisc_sk)->srcprefs,
+ &tmpaddr))
+ return;
+ src_addr = &tmpaddr;
+ }
+
+ if (!dev->addr_len)
+ inc_opt = 0;
+ if (inc_opt)
+ optlen += ndisc_opt_addr_space(dev);
+
+ skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
+ if (!skb)
+ return;
+
+ msg = (struct nd_msg *)skb_put(skb, sizeof(*msg));
+ *msg = (struct nd_msg) {
+ .icmph = {
+ .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT,
+ .icmp6_router = router,
+ .icmp6_solicited = solicited,
+ .icmp6_override = override,
+ },
+ .target = *solicited_addr,
+ };
+
+ if (inc_opt)
+ ndisc_fill_addr_option(skb, ND_OPT_TARGET_LL_ADDR,
+ dev->dev_addr);
+
+
+ ndisc_send_skb(skb, daddr, src_addr);
+}
+
+static void ndisc_send_unsol_na(struct net_device *dev)
+{
+ struct inet6_dev *idev;
+ struct inet6_ifaddr *ifa;
+
+ idev = in6_dev_get(dev);
+ if (!idev)
+ return;
+
+ read_lock_bh(&idev->lock);
+ list_for_each_entry(ifa, &idev->addr_list, if_list) {
+ ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifa->addr,
+ /*router=*/ !!idev->cnf.forwarding,
+ /*solicited=*/ false, /*override=*/ true,
+ /*inc_opt=*/ true);
+ }
+ read_unlock_bh(&idev->lock);
+
+ in6_dev_put(idev);
+}
+
+void ndisc_send_ns(struct net_device *dev, const struct in6_addr *solicit,
+ const struct in6_addr *daddr, const struct in6_addr *saddr)
+{
+ struct sk_buff *skb;
+ struct in6_addr addr_buf;
+ int inc_opt = dev->addr_len;
+ int optlen = 0;
+ struct nd_msg *msg;
+
+ if (!saddr) {
+ if (ipv6_get_lladdr(dev, &addr_buf,
+ (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
+ return;
+ saddr = &addr_buf;
+ }
+
+ if (ipv6_addr_any(saddr))
+ inc_opt = false;
+ if (inc_opt)
+ optlen += ndisc_opt_addr_space(dev);
+
+ skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
+ if (!skb)
+ return;
+
+ msg = (struct nd_msg *)skb_put(skb, sizeof(*msg));
+ *msg = (struct nd_msg) {
+ .icmph = {
+ .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION,
+ },
+ .target = *solicit,
+ };
+
+ if (inc_opt)
+ ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
+ dev->dev_addr);
+
+ ndisc_send_skb(skb, daddr, saddr);
+}
+
+void ndisc_send_rs(struct net_device *dev, const struct in6_addr *saddr,
+ const struct in6_addr *daddr)
+{
+ struct sk_buff *skb;
+ struct rs_msg *msg;
+ int send_sllao = dev->addr_len;
+ int optlen = 0;
+
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+ /*
+ * According to section 2.2 of RFC 4429, we must not
+ * send router solicitations with a sllao from
+ * optimistic addresses, but we may send the solicitation
+ * if we don't include the sllao. So here we check
+ * if our address is optimistic, and if so, we
+ * suppress the inclusion of the sllao.
+ */
+ if (send_sllao) {
+ struct inet6_ifaddr *ifp = ipv6_get_ifaddr(dev_net(dev), saddr,
+ dev, 1);
+ if (ifp) {
+ if (ifp->flags & IFA_F_OPTIMISTIC) {
+ send_sllao = 0;
+ }
+ in6_ifa_put(ifp);
+ } else {
+ send_sllao = 0;
+ }
+ }
+#endif
+ if (send_sllao)
+ optlen += ndisc_opt_addr_space(dev);
+
+ skb = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
+ if (!skb)
+ return;
+
+ msg = (struct rs_msg *)skb_put(skb, sizeof(*msg));
+ *msg = (struct rs_msg) {
+ .icmph = {
+ .icmp6_type = NDISC_ROUTER_SOLICITATION,
+ },
+ };
+
+ if (send_sllao)
+ ndisc_fill_addr_option(skb, ND_OPT_SOURCE_LL_ADDR,
+ dev->dev_addr);
+
+ ndisc_send_skb(skb, daddr, saddr);
+}
+
+
+static void ndisc_error_report(struct neighbour *neigh, struct sk_buff *skb)
+{
+ /*
+ * "The sender MUST return an ICMP
+ * destination unreachable"
+ */
+ dst_link_failure(skb);
+ kfree_skb(skb);
+}
+
+/* Called with locked neigh: either read or both */
+
+static void ndisc_solicit(struct neighbour *neigh, struct sk_buff *skb)
+{
+ struct in6_addr *saddr = NULL;
+ struct in6_addr mcaddr;
+ struct net_device *dev = neigh->dev;
+ struct in6_addr *target = (struct in6_addr *)&neigh->primary_key;
+ int probes = atomic_read(&neigh->probes);
+
+ if (skb && ipv6_chk_addr_and_flags(dev_net(dev), &ipv6_hdr(skb)->saddr,
+ dev, 1,
+ IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))
+ saddr = &ipv6_hdr(skb)->saddr;
+ probes -= NEIGH_VAR(neigh->parms, UCAST_PROBES);
+ if (probes < 0) {
+ if (!(neigh->nud_state & NUD_VALID)) {
+ ND_PRINTK(1, dbg,
+ "%s: trying to ucast probe in NUD_INVALID: %pI6\n",
+ __func__, target);
+ }
+ ndisc_send_ns(dev, target, target, saddr);
+ } else if ((probes -= NEIGH_VAR(neigh->parms, APP_PROBES)) < 0) {
+ neigh_app_ns(neigh);
+ } else {
+ addrconf_addr_solict_mult(target, &mcaddr);
+ ndisc_send_ns(dev, target, &mcaddr, saddr);
+ }
+}
+
+static int pndisc_is_router(const void *pkey,
+ struct net_device *dev)
+{
+ struct pneigh_entry *n;
+ int ret = -1;
+
+ read_lock_bh(&nd_tbl.lock);
+ n = __pneigh_lookup(&nd_tbl, dev_net(dev), pkey, dev);
+ if (n)
+ ret = !!(n->flags & NTF_ROUTER);
+ read_unlock_bh(&nd_tbl.lock);
+
+ return ret;
+}
+
+static void ndisc_recv_ns(struct sk_buff *skb)
+{
+ struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
+ const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
+ const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
+ u8 *lladdr = NULL;
+ u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
+ offsetof(struct nd_msg, opt));
+ struct ndisc_options ndopts;
+ struct net_device *dev = skb->dev;
+ struct inet6_ifaddr *ifp;
+ struct inet6_dev *idev = NULL;
+ struct neighbour *neigh;
+ int dad = ipv6_addr_any(saddr);
+ bool inc;
+ int is_router = -1;
+
+ if (skb->len < sizeof(struct nd_msg)) {
+ ND_PRINTK(2, warn, "NS: packet too short\n");
+ return;
+ }
+
+ if (ipv6_addr_is_multicast(&msg->target)) {
+ ND_PRINTK(2, warn, "NS: multicast target address\n");
+ return;
+ }
+
+ /*
+ * RFC2461 7.1.1:
+ * DAD has to be destined for solicited node multicast address.
+ */
+ if (dad && !ipv6_addr_is_solict_mult(daddr)) {
+ ND_PRINTK(2, warn, "NS: bad DAD packet (wrong destination)\n");
+ return;
+ }
+
+ if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
+ ND_PRINTK(2, warn, "NS: invalid ND options\n");
+ return;
+ }
+
+ if (ndopts.nd_opts_src_lladdr) {
+ lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr, dev);
+ if (!lladdr) {
+ ND_PRINTK(2, warn,
+ "NS: invalid link-layer address length\n");
+ return;
+ }
+
+ /* RFC2461 7.1.1:
+ * If the IP source address is the unspecified address,
+ * there MUST NOT be source link-layer address option
+ * in the message.
+ */
+ if (dad) {
+ ND_PRINTK(2, warn,
+ "NS: bad DAD packet (link-layer address option)\n");
+ return;
+ }
+ }
+
+ inc = ipv6_addr_is_multicast(daddr);
+
+ ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
+ if (ifp) {
+have_ifp:
+ if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
+ if (dad) {
+ /*
+ * We are colliding with another node
+ * who is doing DAD
+ * so fail our DAD process
+ */
+ addrconf_dad_failure(ifp);
+ return;
+ } else {
+ /*
+ * This is not a dad solicitation.
+ * If we are an optimistic node,
+ * we should respond.
+ * Otherwise, we should ignore it.
+ */
+ if (!(ifp->flags & IFA_F_OPTIMISTIC))
+ goto out;
+ }
+ }
+
+ idev = ifp->idev;
+ } else {
+ struct net *net = dev_net(dev);
+
+ /* perhaps an address on the master device */
+ if (netif_is_l3_slave(dev)) {
+ struct net_device *mdev;
+
+ mdev = netdev_master_upper_dev_get_rcu(dev);
+ if (mdev) {
+ ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
+ if (ifp)
+ goto have_ifp;
+ }
+ }
+
+ idev = in6_dev_get(dev);
+ if (!idev) {
+ /* XXX: count this drop? */
+ return;
+ }
+
+ if (ipv6_chk_acast_addr(net, dev, &msg->target) ||
+ (idev->cnf.forwarding &&
+ (net->ipv6.devconf_all->proxy_ndp || idev->cnf.proxy_ndp) &&
+ (is_router = pndisc_is_router(&msg->target, dev)) >= 0)) {
+ if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) &&
+ skb->pkt_type != PACKET_HOST &&
+ inc &&
+ NEIGH_VAR(idev->nd_parms, PROXY_DELAY) != 0) {
+ /*
+ * for anycast or proxy,
+ * sender should delay its response
+ * by a random time between 0 and
+ * MAX_ANYCAST_DELAY_TIME seconds.
+ * (RFC2461) -- yoshfuji
+ */
+ struct sk_buff *n = skb_clone(skb, GFP_ATOMIC);
+ if (n)
+ pneigh_enqueue(&nd_tbl, idev->nd_parms, n);
+ goto out;
+ }
+ } else
+ goto out;
+ }
+
+ if (is_router < 0)
+ is_router = idev->cnf.forwarding;
+
+ if (dad) {
+ ndisc_send_na(dev, &in6addr_linklocal_allnodes, &msg->target,
+ !!is_router, false, (ifp != NULL), true);
+ goto out;
+ }
+
+ if (inc)
+ NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_mcast);
+ else
+ NEIGH_CACHE_STAT_INC(&nd_tbl, rcv_probes_ucast);
+
+ /*
+ * update / create cache entry
+ * for the source address
+ */
+ neigh = __neigh_lookup(&nd_tbl, saddr, dev,
+ !inc || lladdr || !dev->addr_len);
+ if (neigh)
+ neigh_update(neigh, lladdr, NUD_STALE,
+ NEIGH_UPDATE_F_WEAK_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE);
+ if (neigh || !dev->header_ops) {
+ ndisc_send_na(dev, saddr, &msg->target, !!is_router,
+ true, (ifp != NULL && inc), inc);
+ if (neigh)
+ neigh_release(neigh);
+ }
+
+out:
+ if (ifp)
+ in6_ifa_put(ifp);
+ else
+ in6_dev_put(idev);
+}
+
+static void ndisc_recv_na(struct sk_buff *skb)
+{
+ struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb);
+ struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
+ const struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
+ u8 *lladdr = NULL;
+ u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
+ offsetof(struct nd_msg, opt));
+ struct ndisc_options ndopts;
+ struct net_device *dev = skb->dev;
+ struct inet6_ifaddr *ifp;
+ struct neighbour *neigh;
+
+ if (skb->len < sizeof(struct nd_msg)) {
+ ND_PRINTK(2, warn, "NA: packet too short\n");
+ return;
+ }
+
+ if (ipv6_addr_is_multicast(&msg->target)) {
+ ND_PRINTK(2, warn, "NA: target address is multicast\n");
+ return;
+ }
+
+ if (ipv6_addr_is_multicast(daddr) &&
+ msg->icmph.icmp6_solicited) {
+ ND_PRINTK(2, warn, "NA: solicited NA is multicasted\n");
+ return;
+ }
+
+ if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
+ ND_PRINTK(2, warn, "NS: invalid ND option\n");
+ return;
+ }
+ if (ndopts.nd_opts_tgt_lladdr) {
+ lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, dev);
+ if (!lladdr) {
+ ND_PRINTK(2, warn,
+ "NA: invalid link-layer address length\n");
+ return;
+ }
+ }
+ ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
+ if (ifp) {
+ if (skb->pkt_type != PACKET_LOOPBACK
+ && (ifp->flags & IFA_F_TENTATIVE)) {
+ addrconf_dad_failure(ifp);
+ return;
+ }
+ /* What should we make now? The advertisement
+ is invalid, but ndisc specs say nothing
+ about it. It could be misconfiguration, or
+ an smart proxy agent tries to help us :-)
+
+ We should not print the error if NA has been
+ received from loopback - it is just our own
+ unsolicited advertisement.
+ */
+ if (skb->pkt_type != PACKET_LOOPBACK)
+ ND_PRINTK(1, warn,
+ "NA: someone advertises our address %pI6 on %s!\n",
+ &ifp->addr, ifp->idev->dev->name);
+ in6_ifa_put(ifp);
+ return;
+ }
+ neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
+
+ if (neigh) {
+ u8 old_flags = neigh->flags;
+ struct net *net = dev_net(dev);
+
+ if (neigh->nud_state & NUD_FAILED)
+ goto out;
+
+ /*
+ * Don't update the neighbor cache entry on a proxy NA from
+ * ourselves because either the proxied node is off link or it
+ * has already sent a NA to us.
+ */
+ if (lladdr && !memcmp(lladdr, dev->dev_addr, dev->addr_len) &&
+ net->ipv6.devconf_all->forwarding && net->ipv6.devconf_all->proxy_ndp &&
+ pneigh_lookup(&nd_tbl, net, &msg->target, dev, 0)) {
+ /* XXX: idev->cnf.proxy_ndp */
+ goto out;
+ }
+
+ neigh_update(neigh, lladdr,
+ msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
+ NEIGH_UPDATE_F_WEAK_OVERRIDE|
+ (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
+ NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
+ (msg->icmph.icmp6_router ? NEIGH_UPDATE_F_ISROUTER : 0));
+
+ if ((old_flags & ~neigh->flags) & NTF_ROUTER) {
+ /*
+ * Change: router to host
+ */
+ rt6_clean_tohost(dev_net(dev), saddr);
+ }
+
+out:
+ neigh_release(neigh);
+ }
+}
+
+static void ndisc_recv_rs(struct sk_buff *skb)
+{
+ struct rs_msg *rs_msg = (struct rs_msg *)skb_transport_header(skb);
+ unsigned long ndoptlen = skb->len - sizeof(*rs_msg);
+ struct neighbour *neigh;
+ struct inet6_dev *idev;
+ const struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
+ struct ndisc_options ndopts;
+ u8 *lladdr = NULL;
+
+ if (skb->len < sizeof(*rs_msg))
+ return;
+
+ idev = __in6_dev_get(skb->dev);
+ if (!idev) {
+ ND_PRINTK(1, err, "RS: can't find in6 device\n");
+ return;
+ }
+
+ /* Don't accept RS if we're not in router mode */
+ if (!idev->cnf.forwarding)
+ goto out;
+
+ /*
+ * Don't update NCE if src = ::;
+ * this implies that the source node has no ip address assigned yet.
+ */
+ if (ipv6_addr_any(saddr))
+ goto out;
+
+ /* Parse ND options */
+ if (!ndisc_parse_options(rs_msg->opt, ndoptlen, &ndopts)) {
+ ND_PRINTK(2, notice, "NS: invalid ND option, ignored\n");
+ goto out;
+ }
+
+ if (ndopts.nd_opts_src_lladdr) {
+ lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
+ skb->dev);
+ if (!lladdr)
+ goto out;
+ }
+
+ neigh = __neigh_lookup(&nd_tbl, saddr, skb->dev, 1);
+ if (neigh) {
+ neigh_update(neigh, lladdr, NUD_STALE,
+ NEIGH_UPDATE_F_WEAK_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE_ISROUTER);
+ neigh_release(neigh);
+ }
+out:
+ return;
+}
+
+static void ndisc_ra_useropt(struct sk_buff *ra, struct nd_opt_hdr *opt)
+{
+ struct icmp6hdr *icmp6h = (struct icmp6hdr *)skb_transport_header(ra);
+ struct sk_buff *skb;
+ struct nlmsghdr *nlh;
+ struct nduseroptmsg *ndmsg;
+ struct net *net = dev_net(ra->dev);
+ int err;
+ int base_size = NLMSG_ALIGN(sizeof(struct nduseroptmsg)
+ + (opt->nd_opt_len << 3));
+ size_t msg_size = base_size + nla_total_size(sizeof(struct in6_addr));
+
+ skb = nlmsg_new(msg_size, GFP_ATOMIC);
+ if (!skb) {
+ err = -ENOBUFS;
+ goto errout;
+ }
+
+ nlh = nlmsg_put(skb, 0, 0, RTM_NEWNDUSEROPT, base_size, 0);
+ if (!nlh) {
+ goto nla_put_failure;
+ }
+
+ ndmsg = nlmsg_data(nlh);
+ ndmsg->nduseropt_family = AF_INET6;
+ ndmsg->nduseropt_ifindex = ra->dev->ifindex;
+ ndmsg->nduseropt_icmp_type = icmp6h->icmp6_type;
+ ndmsg->nduseropt_icmp_code = icmp6h->icmp6_code;
+ ndmsg->nduseropt_opts_len = opt->nd_opt_len << 3;
+
+ memcpy(ndmsg + 1, opt, opt->nd_opt_len << 3);
+
+ if (nla_put_in6_addr(skb, NDUSEROPT_SRCADDR, &ipv6_hdr(ra)->saddr))
+ goto nla_put_failure;
+ nlmsg_end(skb, nlh);
+
+ rtnl_notify(skb, net, 0, RTNLGRP_ND_USEROPT, NULL, GFP_ATOMIC);
+ return;
+
+nla_put_failure:
+ nlmsg_free(skb);
+ err = -EMSGSIZE;
+errout:
+ rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err);
+}
+
+static void ndisc_router_discovery(struct sk_buff *skb)
+{
+ struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb);
+ struct neighbour *neigh = NULL;
+ struct inet6_dev *in6_dev;
+ struct rt6_info *rt = NULL;
+ int lifetime;
+ struct ndisc_options ndopts;
+ int optlen;
+ unsigned int pref = 0;
+ __u32 old_if_flags;
+ bool send_ifinfo_notify = false;
+
+ __u8 *opt = (__u8 *)(ra_msg + 1);
+
+ optlen = (skb_tail_pointer(skb) - skb_transport_header(skb)) -
+ sizeof(struct ra_msg);
+
+ ND_PRINTK(2, info,
+ "RA: %s, dev: %s\n",
+ __func__, skb->dev->name);
+ if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
+ ND_PRINTK(2, warn, "RA: source address is not link-local\n");
+ return;
+ }
+ if (optlen < 0) {
+ ND_PRINTK(2, warn, "RA: packet too short\n");
+ return;
+ }
+
+#ifdef CONFIG_IPV6_NDISC_NODETYPE
+ if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) {
+ ND_PRINTK(2, warn, "RA: from host or unauthorized router\n");
+ return;
+ }
+#endif
+
+ /*
+ * set the RA_RECV flag in the interface
+ */
+
+ in6_dev = __in6_dev_get(skb->dev);
+ if (!in6_dev) {
+ ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n",
+ skb->dev->name);
+ return;
+ }
+
+ if (!ndisc_parse_options(opt, optlen, &ndopts)) {
+ ND_PRINTK(2, warn, "RA: invalid ND options\n");
+ return;
+ }
+
+ if (!ipv6_accept_ra(in6_dev)) {
+ ND_PRINTK(2, info,
+ "RA: %s, did not accept ra for dev: %s\n",
+ __func__, skb->dev->name);
+ goto skip_linkparms;
+ }
+
+#ifdef CONFIG_IPV6_NDISC_NODETYPE
+ /* skip link-specific parameters from interior routers */
+ if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
+ ND_PRINTK(2, info,
+ "RA: %s, nodetype is NODEFAULT, dev: %s\n",
+ __func__, skb->dev->name);
+ goto skip_linkparms;
+ }
+#endif
+
+ if (in6_dev->if_flags & IF_RS_SENT) {
+ /*
+ * flag that an RA was received after an RS was sent
+ * out on this interface.
+ */
+ in6_dev->if_flags |= IF_RA_RCVD;
+ }
+
+ /*
+ * Remember the managed/otherconf flags from most recently
+ * received RA message (RFC 2462) -- yoshfuji
+ */
+ old_if_flags = in6_dev->if_flags;
+ in6_dev->if_flags = (in6_dev->if_flags & ~(IF_RA_MANAGED |
+ IF_RA_OTHERCONF)) |
+ (ra_msg->icmph.icmp6_addrconf_managed ?
+ IF_RA_MANAGED : 0) |
+ (ra_msg->icmph.icmp6_addrconf_other ?
+ IF_RA_OTHERCONF : 0);
+
+ if (old_if_flags != in6_dev->if_flags)
+ send_ifinfo_notify = true;
+
+ if (!in6_dev->cnf.accept_ra_defrtr) {
+ ND_PRINTK(2, info,
+ "RA: %s, defrtr is false for dev: %s\n",
+ __func__, skb->dev->name);
+ goto skip_defrtr;
+ }
+
+ /* Do not accept RA with source-addr found on local machine unless
+ * accept_ra_from_local is set to true.
+ */
+ if (!in6_dev->cnf.accept_ra_from_local &&
+ ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
+ in6_dev->dev, 0)) {
+ ND_PRINTK(2, info,
+ "RA from local address detected on dev: %s: default router ignored\n",
+ skb->dev->name);
+ goto skip_defrtr;
+ }
+
+ lifetime = ntohs(ra_msg->icmph.icmp6_rt_lifetime);
+
+#ifdef CONFIG_IPV6_ROUTER_PREF
+ pref = ra_msg->icmph.icmp6_router_pref;
+ /* 10b is handled as if it were 00b (medium) */
+ if (pref == ICMPV6_ROUTER_PREF_INVALID ||
+ !in6_dev->cnf.accept_ra_rtr_pref)
+ pref = ICMPV6_ROUTER_PREF_MEDIUM;
+#endif
+
+ rt = rt6_get_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev);
+
+ if (rt) {
+ neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
+ if (!neigh) {
+ ND_PRINTK(0, err,
+ "RA: %s got default router without neighbour\n",
+ __func__);
+ ip6_rt_put(rt);
+ return;
+ }
+ }
+ if (rt && lifetime == 0) {
+ ip6_del_rt(rt);
+ rt = NULL;
+ }
+
+ ND_PRINTK(3, info, "RA: rt: %p lifetime: %d, for dev: %s\n",
+ rt, lifetime, skb->dev->name);
+ if (!rt && lifetime) {
+ ND_PRINTK(3, info, "RA: adding default router\n");
+
+ rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref);
+ if (!rt) {
+ ND_PRINTK(0, err,
+ "RA: %s failed to add default route\n",
+ __func__);
+ return;
+ }
+
+ neigh = dst_neigh_lookup(&rt->dst, &ipv6_hdr(skb)->saddr);
+ if (!neigh) {
+ ND_PRINTK(0, err,
+ "RA: %s got default router without neighbour\n",
+ __func__);
+ ip6_rt_put(rt);
+ return;
+ }
+ neigh->flags |= NTF_ROUTER;
+ } else if (rt) {
+ rt->rt6i_flags = (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
+ }
+
+ if (rt)
+ rt6_set_expires(rt, jiffies + (HZ * lifetime));
+ if (in6_dev->cnf.accept_ra_min_hop_limit < 256 &&
+ ra_msg->icmph.icmp6_hop_limit) {
+ if (in6_dev->cnf.accept_ra_min_hop_limit <= ra_msg->icmph.icmp6_hop_limit) {
+ in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+ if (rt)
+ dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
+ ra_msg->icmph.icmp6_hop_limit);
+ } else {
+ ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than minimum\n");
+ }
+ }
+
+skip_defrtr:
+
+ /*
+ * Update Reachable Time and Retrans Timer
+ */
+
+ if (in6_dev->nd_parms) {
+ unsigned long rtime = ntohl(ra_msg->retrans_timer);
+
+ if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/HZ) {
+ rtime = (rtime*HZ)/1000;
+ if (rtime < HZ/10)
+ rtime = HZ/10;
+ NEIGH_VAR_SET(in6_dev->nd_parms, RETRANS_TIME, rtime);
+ in6_dev->tstamp = jiffies;
+ send_ifinfo_notify = true;
+ }
+
+ rtime = ntohl(ra_msg->reachable_time);
+ if (rtime && rtime/1000 < MAX_SCHEDULE_TIMEOUT/(3*HZ)) {
+ rtime = (rtime*HZ)/1000;
+
+ if (rtime < HZ/10)
+ rtime = HZ/10;
+
+ if (rtime != NEIGH_VAR(in6_dev->nd_parms, BASE_REACHABLE_TIME)) {
+ NEIGH_VAR_SET(in6_dev->nd_parms,
+ BASE_REACHABLE_TIME, rtime);
+ NEIGH_VAR_SET(in6_dev->nd_parms,
+ GC_STALETIME, 3 * rtime);
+ in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime);
+ in6_dev->tstamp = jiffies;
+ send_ifinfo_notify = true;
+ }
+ }
+ }
+
+ /*
+ * Send a notify if RA changed managed/otherconf flags or timer settings
+ */
+ if (send_ifinfo_notify)
+ inet6_ifinfo_notify(RTM_NEWLINK, in6_dev);
+
+skip_linkparms:
+
+ /*
+ * Process options.
+ */
+
+ if (!neigh)
+ neigh = __neigh_lookup(&nd_tbl, &ipv6_hdr(skb)->saddr,
+ skb->dev, 1);
+ if (neigh) {
+ u8 *lladdr = NULL;
+ if (ndopts.nd_opts_src_lladdr) {
+ lladdr = ndisc_opt_addr_data(ndopts.nd_opts_src_lladdr,
+ skb->dev);
+ if (!lladdr) {
+ ND_PRINTK(2, warn,
+ "RA: invalid link-layer address length\n");
+ goto out;
+ }
+ }
+ neigh_update(neigh, lladdr, NUD_STALE,
+ NEIGH_UPDATE_F_WEAK_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE|
+ NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
+ NEIGH_UPDATE_F_ISROUTER);
+ }
+
+ if (!ipv6_accept_ra(in6_dev)) {
+ ND_PRINTK(2, info,
+ "RA: %s, accept_ra is false for dev: %s\n",
+ __func__, skb->dev->name);
+ goto out;
+ }
+
+#ifdef CONFIG_IPV6_ROUTE_INFO
+ if (!in6_dev->cnf.accept_ra_from_local &&
+ ipv6_chk_addr(dev_net(in6_dev->dev), &ipv6_hdr(skb)->saddr,
+ in6_dev->dev, 0)) {
+ ND_PRINTK(2, info,
+ "RA from local address detected on dev: %s: router info ignored.\n",
+ skb->dev->name);
+ goto skip_routeinfo;
+ }
+
+ if (in6_dev->cnf.accept_ra_rtr_pref && ndopts.nd_opts_ri) {
+ struct nd_opt_hdr *p;
+ for (p = ndopts.nd_opts_ri;
+ p;
+ p = ndisc_next_option(p, ndopts.nd_opts_ri_end)) {
+ struct route_info *ri = (struct route_info *)p;
+#ifdef CONFIG_IPV6_NDISC_NODETYPE
+ if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT &&
+ ri->prefix_len == 0)
+ continue;
+#endif
+ if (ri->prefix_len == 0 &&
+ !in6_dev->cnf.accept_ra_defrtr)
+ continue;
+ if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
+ continue;
+ rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,
+ &ipv6_hdr(skb)->saddr);
+ }
+ }
+
+skip_routeinfo:
+#endif
+
+#ifdef CONFIG_IPV6_NDISC_NODETYPE
+ /* skip link-specific ndopts from interior routers */
+ if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) {
+ ND_PRINTK(2, info,
+ "RA: %s, nodetype is NODEFAULT (interior routes), dev: %s\n",
+ __func__, skb->dev->name);
+ goto out;
+ }
+#endif
+
+ if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) {
+ struct nd_opt_hdr *p;
+ for (p = ndopts.nd_opts_pi;
+ p;
+ p = ndisc_next_option(p, ndopts.nd_opts_pi_end)) {
+ addrconf_prefix_rcv(skb->dev, (u8 *)p,
+ (p->nd_opt_len) << 3,
+ ndopts.nd_opts_src_lladdr != NULL);
+ }
+ }
+
+ if (ndopts.nd_opts_mtu && in6_dev->cnf.accept_ra_mtu) {
+ __be32 n;
+ u32 mtu;
+
+ memcpy(&n, ((u8 *)(ndopts.nd_opts_mtu+1))+2, sizeof(mtu));
+ mtu = ntohl(n);
+
+ if (mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) {
+ ND_PRINTK(2, warn, "RA: invalid mtu: %d\n", mtu);
+ } else if (in6_dev->cnf.mtu6 != mtu) {
+ in6_dev->cnf.mtu6 = mtu;
+
+ if (rt)
+ dst_metric_set(&rt->dst, RTAX_MTU, mtu);
+
+ rt6_mtu_change(skb->dev, mtu);
+ }
+ }
+
+ if (ndopts.nd_useropts) {
+ struct nd_opt_hdr *p;
+ for (p = ndopts.nd_useropts;
+ p;
+ p = ndisc_next_useropt(p, ndopts.nd_useropts_end)) {
+ ndisc_ra_useropt(skb, p);
+ }
+ }
+
+ if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) {
+ ND_PRINTK(2, warn, "RA: invalid RA options\n");
+ }
+out:
+ ip6_rt_put(rt);
+ if (neigh)
+ neigh_release(neigh);
+}
+
+static void ndisc_redirect_rcv(struct sk_buff *skb)
+{
+ u8 *hdr;
+ struct ndisc_options ndopts;
+ struct rd_msg *msg = (struct rd_msg *)skb_transport_header(skb);
+ u32 ndoptlen = skb_tail_pointer(skb) - (skb_transport_header(skb) +
+ offsetof(struct rd_msg, opt));
+
+#ifdef CONFIG_IPV6_NDISC_NODETYPE
+ switch (skb->ndisc_nodetype) {
+ case NDISC_NODETYPE_HOST:
+ case NDISC_NODETYPE_NODEFAULT:
+ ND_PRINTK(2, warn,
+ "Redirect: from host or unauthorized router\n");
+ return;
+ }
+#endif
+
+ if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
+ ND_PRINTK(2, warn,
+ "Redirect: source address is not link-local\n");
+ return;
+ }
+
+ if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts))
+ return;
+
+ if (!ndopts.nd_opts_rh) {
+ ip6_redirect_no_header(skb, dev_net(skb->dev),
+ skb->dev->ifindex, 0);
+ return;
+ }
+
+ hdr = (u8 *)ndopts.nd_opts_rh;
+ hdr += 8;
+ if (!pskb_pull(skb, hdr - skb_transport_header(skb)))
+ return;
+
+ icmpv6_notify(skb, NDISC_REDIRECT, 0, 0);
+}
+
+static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb,
+ struct sk_buff *orig_skb,
+ int rd_len)
+{
+ u8 *opt = skb_put(skb, rd_len);
+
+ memset(opt, 0, 8);
+ *(opt++) = ND_OPT_REDIRECT_HDR;
+ *(opt++) = (rd_len >> 3);
+ opt += 6;
+
+ memcpy(opt, ipv6_hdr(orig_skb), rd_len - 8);
+}
+
+void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
+{
+ struct net_device *dev = skb->dev;
+ struct net *net = dev_net(dev);
+ struct sock *sk = net->ipv6.ndisc_sk;
+ int optlen = 0;
+ struct inet_peer *peer;
+ struct sk_buff *buff;
+ struct rd_msg *msg;
+ struct in6_addr saddr_buf;
+ struct rt6_info *rt;
+ struct dst_entry *dst;
+ struct flowi6 fl6;
+ int rd_len;
+ u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
+ int oif = l3mdev_fib_oif(dev);
+ bool ret;
+
+ if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
+ ND_PRINTK(2, warn, "Redirect: no link-local address on %s\n",
+ dev->name);
+ return;
+ }
+
+ if (!ipv6_addr_equal(&ipv6_hdr(skb)->daddr, target) &&
+ ipv6_addr_type(target) != (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
+ ND_PRINTK(2, warn,
+ "Redirect: target address is not link-local unicast\n");
+ return;
+ }
+
+ icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
+ &saddr_buf, &ipv6_hdr(skb)->saddr, oif);
+
+ if (oif != skb->dev->ifindex)
+ fl6.flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
+
+ dst = ip6_route_output(net, NULL, &fl6);
+ if (dst->error) {
+ dst_release(dst);
+ return;
+ }
+ dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
+ if (IS_ERR(dst))
+ return;
+
+ rt = (struct rt6_info *) dst;
+
+ if (rt->rt6i_flags & RTF_GATEWAY) {
+ ND_PRINTK(2, warn,
+ "Redirect: destination is not a neighbour\n");
+ goto release;
+ }
+ peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr, 1);
+ ret = inet_peer_xrlim_allow(peer, 1*HZ);
+ if (peer)
+ inet_putpeer(peer);
+ if (!ret)
+ goto release;
+
+ if (dev->addr_len) {
+ struct neighbour *neigh = dst_neigh_lookup(skb_dst(skb), target);
+ if (!neigh) {
+ ND_PRINTK(2, warn,
+ "Redirect: no neigh for target address\n");
+ goto release;
+ }
+
+ read_lock_bh(&neigh->lock);
+ if (neigh->nud_state & NUD_VALID) {
+ memcpy(ha_buf, neigh->ha, dev->addr_len);
+ read_unlock_bh(&neigh->lock);
+ ha = ha_buf;
+ optlen += ndisc_opt_addr_space(dev);
+ } else
+ read_unlock_bh(&neigh->lock);
+
+ neigh_release(neigh);
+ }
+
+ rd_len = min_t(unsigned int,
+ IPV6_MIN_MTU - sizeof(struct ipv6hdr) - sizeof(*msg) - optlen,
+ skb->len + 8);
+ rd_len &= ~0x7;
+ optlen += rd_len;
+
+ buff = ndisc_alloc_skb(dev, sizeof(*msg) + optlen);
+ if (!buff)
+ goto release;
+
+ msg = (struct rd_msg *)skb_put(buff, sizeof(*msg));
+ *msg = (struct rd_msg) {
+ .icmph = {
+ .icmp6_type = NDISC_REDIRECT,
+ },
+ .target = *target,
+ .dest = ipv6_hdr(skb)->daddr,
+ };
+
+ /*
+ * include target_address option
+ */
+
+ if (ha)
+ ndisc_fill_addr_option(buff, ND_OPT_TARGET_LL_ADDR, ha);
+
+ /*
+ * build redirect option and copy skb over to the new packet.
+ */
+
+ if (rd_len)
+ ndisc_fill_redirect_hdr_option(buff, skb, rd_len);
+
+ skb_dst_set(buff, dst);
+ ndisc_send_skb(buff, &ipv6_hdr(skb)->saddr, &saddr_buf);
+ return;
+
+release:
+ dst_release(dst);
+}
+
+static void pndisc_redo(struct sk_buff *skb)
+{
+ ndisc_recv_ns(skb);
+ kfree_skb(skb);
+}
+
+static bool ndisc_suppress_frag_ndisc(struct sk_buff *skb)
+{
+ struct inet6_dev *idev = __in6_dev_get(skb->dev);
+
+ if (!idev)
+ return true;
+ if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED &&
+ idev->cnf.suppress_frag_ndisc) {
+ net_warn_ratelimited("Received fragmented ndisc packet. Carefully consider disabling suppress_frag_ndisc.\n");
+ return true;
+ }
+ return false;
+}
+
+int ndisc_rcv(struct sk_buff *skb)
+{
+ struct nd_msg *msg;
+
+ if (ndisc_suppress_frag_ndisc(skb))
+ return 0;
+
+ if (skb_linearize(skb))
+ return 0;
+
+ msg = (struct nd_msg *)skb_transport_header(skb);
+
+ __skb_push(skb, skb->data - skb_transport_header(skb));
+
+ if (ipv6_hdr(skb)->hop_limit != 255) {
+ ND_PRINTK(2, warn, "NDISC: invalid hop-limit: %d\n",
+ ipv6_hdr(skb)->hop_limit);
+ return 0;
+ }
+
+ if (msg->icmph.icmp6_code != 0) {
+ ND_PRINTK(2, warn, "NDISC: invalid ICMPv6 code: %d\n",
+ msg->icmph.icmp6_code);
+ return 0;
+ }
+
+ memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
+
+ switch (msg->icmph.icmp6_type) {
+ case NDISC_NEIGHBOUR_SOLICITATION:
+ ndisc_recv_ns(skb);
+ break;
+
+ case NDISC_NEIGHBOUR_ADVERTISEMENT:
+ ndisc_recv_na(skb);
+ break;
+
+ case NDISC_ROUTER_SOLICITATION:
+ ndisc_recv_rs(skb);
+ break;
+
+ case NDISC_ROUTER_ADVERTISEMENT:
+ ndisc_router_discovery(skb);
+ break;
+
+ case NDISC_REDIRECT:
+ ndisc_redirect_rcv(skb);
+ break;
+ }
+
+ return 0;
+}
+
+static int ndisc_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct netdev_notifier_change_info *change_info;
+ struct net *net = dev_net(dev);
+ struct inet6_dev *idev;
+
+ switch (event) {
+ case NETDEV_CHANGEADDR:
+ neigh_changeaddr(&nd_tbl, dev);
+ fib6_run_gc(0, net, false);
+ idev = in6_dev_get(dev);
+ if (!idev)
+ break;
+ if (idev->cnf.ndisc_notify)
+ ndisc_send_unsol_na(dev);
+ in6_dev_put(idev);
+ break;
+ case NETDEV_CHANGE:
+ change_info = ptr;
+ if (change_info->flags_changed & IFF_NOARP)
+ neigh_changeaddr(&nd_tbl, dev);
+ break;
+ case NETDEV_DOWN:
+ neigh_ifdown(&nd_tbl, dev);
+ fib6_run_gc(0, net, false);
+ break;
+ case NETDEV_NOTIFY_PEERS:
+ ndisc_send_unsol_na(dev);
+ break;
+ default:
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block ndisc_netdev_notifier = {
+ .notifier_call = ndisc_netdev_event,
+};
+
+#ifdef CONFIG_SYSCTL
+static void ndisc_warn_deprecated_sysctl(struct ctl_table *ctl,
+ const char *func, const char *dev_name)
+{
+ static char warncomm[TASK_COMM_LEN];
+ static int warned;
+ if (strcmp(warncomm, current->comm) && warned < 5) {
+ strcpy(warncomm, current->comm);
+ pr_warn("process `%s' is using deprecated sysctl (%s) net.ipv6.neigh.%s.%s - use net.ipv6.neigh.%s.%s_ms instead\n",
+ warncomm, func,
+ dev_name, ctl->procname,
+ dev_name, ctl->procname);
+ warned++;
+ }
+}
+
+int ndisc_ifinfo_sysctl_change(struct ctl_table *ctl, int write, void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net_device *dev = ctl->extra1;
+ struct inet6_dev *idev;
+ int ret;
+
+ if ((strcmp(ctl->procname, "retrans_time") == 0) ||
+ (strcmp(ctl->procname, "base_reachable_time") == 0))
+ ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default");
+
+ if (strcmp(ctl->procname, "retrans_time") == 0)
+ ret = neigh_proc_dointvec(ctl, write, buffer, lenp, ppos);
+
+ else if (strcmp(ctl->procname, "base_reachable_time") == 0)
+ ret = neigh_proc_dointvec_jiffies(ctl, write,
+ buffer, lenp, ppos);
+
+ else if ((strcmp(ctl->procname, "retrans_time_ms") == 0) ||
+ (strcmp(ctl->procname, "base_reachable_time_ms") == 0))
+ ret = neigh_proc_dointvec_ms_jiffies(ctl, write,
+ buffer, lenp, ppos);
+ else
+ ret = -1;
+
+ if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) {
+ if (ctl->data == &NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME))
+ idev->nd_parms->reachable_time =
+ neigh_rand_reach_time(NEIGH_VAR(idev->nd_parms, BASE_REACHABLE_TIME));
+ idev->tstamp = jiffies;
+ inet6_ifinfo_notify(RTM_NEWLINK, idev);
+ in6_dev_put(idev);
+ }
+ return ret;
+}
+
+
+#endif
+
+static int __net_init ndisc_net_init(struct net *net)
+{
+ struct ipv6_pinfo *np;
+ struct sock *sk;
+ int err;
+
+ err = inet_ctl_sock_create(&sk, PF_INET6,
+ SOCK_RAW, IPPROTO_ICMPV6, net);
+ if (err < 0) {
+ ND_PRINTK(0, err,
+ "NDISC: Failed to initialize the control socket (err %d)\n",
+ err);
+ return err;
+ }
+
+ net->ipv6.ndisc_sk = sk;
+
+ np = inet6_sk(sk);
+ np->hop_limit = 255;
+ /* Do not loopback ndisc messages */
+ np->mc_loop = 0;
+
+ return 0;
+}
+
+static void __net_exit ndisc_net_exit(struct net *net)
+{
+ inet_ctl_sock_destroy(net->ipv6.ndisc_sk);
+}
+
+static struct pernet_operations ndisc_net_ops = {
+ .init = ndisc_net_init,
+ .exit = ndisc_net_exit,
+};
+
+int __init ndisc_init(void)
+{
+ int err;
+
+ err = register_pernet_subsys(&ndisc_net_ops);
+ if (err)
+ return err;
+ /*
+ * Initialize the neighbour table
+ */
+ neigh_table_init(NEIGH_ND_TABLE, &nd_tbl);
+
+#ifdef CONFIG_SYSCTL
+ err = neigh_sysctl_register(NULL, &nd_tbl.parms,
+ ndisc_ifinfo_sysctl_change);
+ if (err)
+ goto out_unregister_pernet;
+out:
+#endif
+ return err;
+
+#ifdef CONFIG_SYSCTL
+out_unregister_pernet:
+ unregister_pernet_subsys(&ndisc_net_ops);
+ goto out;
+#endif
+}
+
+int __init ndisc_late_init(void)
+{
+ return register_netdevice_notifier(&ndisc_netdev_notifier);
+}
+
+void ndisc_late_cleanup(void)
+{
+ unregister_netdevice_notifier(&ndisc_netdev_notifier);
+}
+
+void ndisc_cleanup(void)
+{
+#ifdef CONFIG_SYSCTL
+ neigh_sysctl_unregister(&nd_tbl.parms);
+#endif
+ neigh_table_clear(NEIGH_ND_TABLE, &nd_tbl);
+ unregister_pernet_subsys(&ndisc_net_ops);
+}