| /* |
| * 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: |
| * |
| * 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 |
| */ |
| |
| /* Set to 3 to get tracing... */ |
| #define ND_DEBUG 1 |
| |
| #define ND_PRINTK(fmt, args...) do { if (net_ratelimit()) { printk(fmt, ## args); } } while(0) |
| #define ND_NOPRINTK(x...) do { ; } while(0) |
| #define ND_PRINTK0 ND_PRINTK |
| #define ND_PRINTK1 ND_NOPRINTK |
| #define ND_PRINTK2 ND_NOPRINTK |
| #define ND_PRINTK3 ND_NOPRINTK |
| #if ND_DEBUG >= 1 |
| #undef ND_PRINTK1 |
| #define ND_PRINTK1 ND_PRINTK |
| #endif |
| #if ND_DEBUG >= 2 |
| #undef ND_PRINTK2 |
| #define ND_PRINTK2 ND_PRINTK |
| #endif |
| #if ND_DEBUG >= 3 |
| #undef ND_PRINTK3 |
| #define ND_PRINTK3 ND_PRINTK |
| #endif |
| |
| #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> |
| #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/flow.h> |
| #include <net/ip6_checksum.h> |
| #include <linux/proc_fs.h> |
| |
| #include <linux/netfilter.h> |
| #include <linux/netfilter_ipv6.h> |
| |
| static struct socket *ndisc_socket; |
| |
| static u32 ndisc_hash(const void *pkey, const struct net_device *dev); |
| 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 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, |
| .hh_output = dev_queue_xmit, |
| .queue_xmit = dev_queue_xmit, |
| }; |
| |
| static 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, |
| .hh_output = dev_queue_xmit, |
| .queue_xmit = dev_queue_xmit, |
| }; |
| |
| |
| static struct neigh_ops ndisc_direct_ops = { |
| .family = AF_INET6, |
| .output = dev_queue_xmit, |
| .connected_output = dev_queue_xmit, |
| .hh_output = dev_queue_xmit, |
| .queue_xmit = dev_queue_xmit, |
| }; |
| |
| struct neigh_table nd_tbl = { |
| .family = AF_INET6, |
| .entry_size = sizeof(struct neighbour) + sizeof(struct in6_addr), |
| .key_len = sizeof(struct in6_addr), |
| .hash = ndisc_hash, |
| .constructor = ndisc_constructor, |
| .pconstructor = pndisc_constructor, |
| .pdestructor = pndisc_destructor, |
| .proxy_redo = pndisc_redo, |
| .id = "ndisc_cache", |
| .parms = { |
| .tbl = &nd_tbl, |
| .base_reachable_time = 30 * HZ, |
| .retrans_time = 1 * HZ, |
| .gc_staletime = 60 * HZ, |
| .reachable_time = 30 * HZ, |
| .delay_probe_time = 5 * HZ, |
| .queue_len = 3, |
| .ucast_probes = 3, |
| .mcast_probes = 3, |
| .anycast_delay = 1 * HZ, |
| .proxy_delay = (8 * HZ) / 10, |
| .proxy_qlen = 64, |
| }, |
| .gc_interval = 30 * HZ, |
| .gc_thresh1 = 128, |
| .gc_thresh2 = 512, |
| .gc_thresh3 = 1024, |
| }; |
| |
| /* ND options */ |
| struct ndisc_options { |
| struct nd_opt_hdr *nd_opt_array[__ND_OPT_ARRAY_MAX]; |
| #ifdef CONFIG_IPV6_ROUTE_INFO |
| struct nd_opt_hdr *nd_opts_ri; |
| struct nd_opt_hdr *nd_opts_ri_end; |
| #endif |
| }; |
| |
| #define nd_opts_src_lladdr nd_opt_array[ND_OPT_SOURCE_LL_ADDR] |
| #define nd_opts_tgt_lladdr nd_opt_array[ND_OPT_TARGET_LL_ADDR] |
| #define nd_opts_pi nd_opt_array[ND_OPT_PREFIX_INFO] |
| #define nd_opts_pi_end nd_opt_array[__ND_OPT_PREFIX_INFO_END] |
| #define nd_opts_rh nd_opt_array[ND_OPT_REDIRECT_HDR] |
| #define nd_opts_mtu nd_opt_array[ND_OPT_MTU] |
| |
| #define NDISC_OPT_SPACE(len) (((len)+2+7)&~7) |
| |
| /* |
| * Return the padding between the option length and the start of the |
| * link addr. Currently only IP-over-InfiniBand needs this, although |
| * if RFC 3831 IPv6-over-Fibre Channel is ever implemented it may |
| * also need a pad of 2. |
| */ |
| static int ndisc_addr_option_pad(unsigned short type) |
| { |
| switch (type) { |
| case ARPHRD_INFINIBAND: return 2; |
| default: return 0; |
| } |
| } |
| |
| static inline int ndisc_opt_addr_space(struct net_device *dev) |
| { |
| return NDISC_OPT_SPACE(dev->addr_len + ndisc_addr_option_pad(dev->type)); |
| } |
| |
| static u8 *ndisc_fill_addr_option(u8 *opt, int type, void *data, int data_len, |
| unsigned short addr_type) |
| { |
| int space = NDISC_OPT_SPACE(data_len); |
| int pad = ndisc_addr_option_pad(addr_type); |
| |
| 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; |
| if ((space -= data_len) > 0) |
| memset(opt, 0, space); |
| return opt + 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 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_PRINTK2(KERN_WARNING |
| "%s(): duplicated ND6 option found: type=%d\n", |
| __FUNCTION__, |
| 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] == 0) |
| 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: |
| /* |
| * Unknown options must be silently ignored, |
| * to accommodate future extension to the protocol. |
| */ |
| ND_PRINTK2(KERN_NOTICE |
| "%s(): ignored unsupported option; type=%d, len=%d\n", |
| __FUNCTION__, |
| nd_opt->nd_opt_type, nd_opt->nd_opt_len); |
| } |
| opt_len -= l; |
| nd_opt = ((void *)nd_opt) + l; |
| } |
| return ndopts; |
| } |
| |
| static inline u8 *ndisc_opt_addr_data(struct nd_opt_hdr *p, |
| struct net_device *dev) |
| { |
| u8 *lladdr = (u8 *)(p + 1); |
| int lladdrlen = p->nd_opt_len << 3; |
| int prepad = ndisc_addr_option_pad(dev->type); |
| if (lladdrlen != NDISC_OPT_SPACE(dev->addr_len + prepad)) |
| return NULL; |
| return (lladdr + prepad); |
| } |
| |
| int ndisc_mc_map(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_IEEE802_TR: |
| ipv6_tr_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, buf); |
| return 0; |
| 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) |
| { |
| const u32 *p32 = pkey; |
| u32 addr_hash, i; |
| |
| addr_hash = 0; |
| for (i = 0; i < (sizeof(struct in6_addr) / sizeof(u32)); i++) |
| addr_hash ^= *p32++; |
| |
| return jhash_2words(addr_hash, dev->ifindex, nd_tbl.hash_rnd); |
| } |
| |
| 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; |
| int is_multicast = ipv6_addr_is_multicast(addr); |
| |
| rcu_read_lock(); |
| in6_dev = in6_dev_get(dev); |
| if (in6_dev == NULL) { |
| rcu_read_unlock(); |
| return -EINVAL; |
| } |
| |
| parms = in6_dev->nd_parms; |
| __neigh_parms_put(neigh->parms); |
| neigh->parms = neigh_parms_clone(parms); |
| rcu_read_unlock(); |
| |
| 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->ops->queue_xmit; |
| } 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 == NULL || __in6_dev_get(dev) == NULL) |
| 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 == NULL || __in6_dev_get(dev) == NULL) |
| return; |
| addrconf_addr_solict_mult(addr, &maddr); |
| ipv6_dev_mc_dec(dev, &maddr); |
| } |
| |
| /* |
| * Send a Neighbour Advertisement |
| */ |
| |
| static inline void ndisc_flow_init(struct flowi *fl, u8 type, |
| struct in6_addr *saddr, struct in6_addr *daddr, |
| int oif) |
| { |
| memset(fl, 0, sizeof(*fl)); |
| ipv6_addr_copy(&fl->fl6_src, saddr); |
| ipv6_addr_copy(&fl->fl6_dst, daddr); |
| fl->proto = IPPROTO_ICMPV6; |
| fl->fl_icmp_type = type; |
| fl->fl_icmp_code = 0; |
| fl->oif = oif; |
| security_sk_classify_flow(ndisc_socket->sk, fl); |
| } |
| |
| static void __ndisc_send(struct net_device *dev, |
| struct neighbour *neigh, |
| struct in6_addr *daddr, struct in6_addr *saddr, |
| struct icmp6hdr *icmp6h, struct in6_addr *target, |
| int llinfo) |
| { |
| struct flowi fl; |
| struct dst_entry *dst; |
| struct sock *sk = ndisc_socket->sk; |
| struct sk_buff *skb; |
| struct icmp6hdr *hdr; |
| struct inet6_dev *idev; |
| int len; |
| int err; |
| u8 *opt, type; |
| |
| type = icmp6h->icmp6_type; |
| |
| ndisc_flow_init(&fl, type, saddr, daddr, |
| dev->ifindex); |
| |
| dst = ndisc_dst_alloc(dev, neigh, daddr, ip6_output); |
| if (!dst) |
| return; |
| |
| err = xfrm_lookup(&dst, &fl, NULL, 0); |
| if (err < 0) |
| return; |
| |
| if (!dev->addr_len) |
| llinfo = 0; |
| |
| len = sizeof(struct icmp6hdr) + (target ? sizeof(*target) : 0); |
| if (llinfo) |
| len += ndisc_opt_addr_space(dev); |
| |
| skb = sock_alloc_send_skb(sk, |
| (MAX_HEADER + sizeof(struct ipv6hdr) + |
| len + LL_RESERVED_SPACE(dev)), |
| 1, &err); |
| if (!skb) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 ND: %s() failed to allocate an skb.\n", |
| __FUNCTION__); |
| dst_release(dst); |
| return; |
| } |
| |
| skb_reserve(skb, LL_RESERVED_SPACE(dev)); |
| ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len); |
| |
| skb->transport_header = skb->tail; |
| skb_put(skb, len); |
| |
| hdr = (struct icmp6hdr *)skb_transport_header(skb); |
| memcpy(hdr, icmp6h, sizeof(*hdr)); |
| |
| opt = skb_transport_header(skb) + sizeof(struct icmp6hdr); |
| if (target) { |
| ipv6_addr_copy((struct in6_addr *)opt, target); |
| opt += sizeof(*target); |
| } |
| |
| if (llinfo) |
| ndisc_fill_addr_option(opt, llinfo, dev->dev_addr, |
| dev->addr_len, dev->type); |
| |
| hdr->icmp6_cksum = csum_ipv6_magic(saddr, daddr, len, |
| IPPROTO_ICMPV6, |
| csum_partial((__u8 *) hdr, |
| len, 0)); |
| |
| skb->dst = dst; |
| |
| idev = in6_dev_get(dst->dev); |
| IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS); |
| |
| err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, dst_output); |
| if (!err) { |
| ICMP6MSGOUT_INC_STATS(idev, type); |
| ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS); |
| } |
| |
| if (likely(idev != NULL)) |
| in6_dev_put(idev); |
| } |
| |
| static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh, |
| struct in6_addr *daddr, struct in6_addr *solicited_addr, |
| int router, int solicited, int override, int inc_opt) |
| { |
| struct in6_addr tmpaddr; |
| struct inet6_ifaddr *ifp; |
| struct in6_addr *src_addr; |
| struct icmp6hdr icmp6h = { |
| .icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT, |
| }; |
| |
| /* for anycast or proxy, solicited_addr != src_addr */ |
| ifp = ipv6_get_ifaddr(solicited_addr, dev, 1); |
| if (ifp) { |
| src_addr = solicited_addr; |
| if (ifp->flags & IFA_F_OPTIMISTIC) |
| override = 0; |
| in6_ifa_put(ifp); |
| } else { |
| if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr)) |
| return; |
| src_addr = &tmpaddr; |
| } |
| |
| icmp6h.icmp6_router = router; |
| icmp6h.icmp6_solicited = solicited; |
| icmp6h.icmp6_override = override; |
| |
| __ndisc_send(dev, neigh, daddr, src_addr, |
| &icmp6h, solicited_addr, |
| inc_opt ? ND_OPT_TARGET_LL_ADDR : 0); |
| } |
| |
| void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh, |
| struct in6_addr *solicit, |
| struct in6_addr *daddr, struct in6_addr *saddr) |
| { |
| struct in6_addr addr_buf; |
| struct icmp6hdr icmp6h = { |
| .icmp6_type = NDISC_NEIGHBOUR_SOLICITATION, |
| }; |
| |
| if (saddr == NULL) { |
| if (ipv6_get_lladdr(dev, &addr_buf, |
| (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC))) |
| return; |
| saddr = &addr_buf; |
| } |
| |
| __ndisc_send(dev, neigh, daddr, saddr, |
| &icmp6h, solicit, |
| !ipv6_addr_any(saddr) ? ND_OPT_SOURCE_LL_ADDR : 0); |
| } |
| |
| void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr, |
| struct in6_addr *daddr) |
| { |
| struct icmp6hdr icmp6h = { |
| .icmp6_type = NDISC_ROUTER_SOLICITATION, |
| }; |
| int send_sllao = dev->addr_len; |
| |
| #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 |
| * supress the inclusion of the sllao. |
| */ |
| if (send_sllao) { |
| struct inet6_ifaddr *ifp = ipv6_get_ifaddr(saddr, dev, 1); |
| if (ifp) { |
| if (ifp->flags & IFA_F_OPTIMISTIC) { |
| send_sllao = 0; |
| } |
| in6_ifa_put(ifp); |
| } else { |
| send_sllao = 0; |
| } |
| } |
| #endif |
| __ndisc_send(dev, NULL, daddr, saddr, |
| &icmp6h, NULL, |
| send_sllao ? ND_OPT_SOURCE_LL_ADDR : 0); |
| } |
| |
| |
| 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(&ipv6_hdr(skb)->saddr, dev, 1)) |
| saddr = &ipv6_hdr(skb)->saddr; |
| |
| if ((probes -= neigh->parms->ucast_probes) < 0) { |
| if (!(neigh->nud_state & NUD_VALID)) { |
| ND_PRINTK1(KERN_DEBUG |
| "%s(): trying to ucast probe in NUD_INVALID: " |
| NIP6_FMT "\n", |
| __FUNCTION__, |
| NIP6(*target)); |
| } |
| ndisc_send_ns(dev, neigh, target, target, saddr); |
| } else if ((probes -= neigh->parms->app_probes) < 0) { |
| #ifdef CONFIG_ARPD |
| neigh_app_ns(neigh); |
| #endif |
| } else { |
| addrconf_addr_solict_mult(target, &mcaddr); |
| ndisc_send_ns(dev, NULL, target, &mcaddr, saddr); |
| } |
| } |
| |
| static void ndisc_recv_ns(struct sk_buff *skb) |
| { |
| struct nd_msg *msg = (struct nd_msg *)skb_transport_header(skb); |
| struct in6_addr *saddr = &ipv6_hdr(skb)->saddr; |
| struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; |
| u8 *lladdr = NULL; |
| u32 ndoptlen = skb->tail - (skb->transport_header + |
| 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; |
| struct pneigh_entry *pneigh = NULL; |
| int dad = ipv6_addr_any(saddr); |
| int inc; |
| int is_router; |
| |
| if (ipv6_addr_is_multicast(&msg->target)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 NS: multicast target address"); |
| return; |
| } |
| |
| /* |
| * RFC2461 7.1.1: |
| * DAD has to be destined for solicited node multicast address. |
| */ |
| if (dad && |
| !(daddr->s6_addr32[0] == htonl(0xff020000) && |
| daddr->s6_addr32[1] == htonl(0x00000000) && |
| daddr->s6_addr32[2] == htonl(0x00000001) && |
| daddr->s6_addr [12] == 0xff )) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 NS: bad DAD packet (wrong destination)\n"); |
| return; |
| } |
| |
| if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 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_PRINTK2(KERN_WARNING |
| "ICMPv6 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_PRINTK2(KERN_WARNING |
| "ICMPv6 NS: bad DAD packet (link-layer address option)\n"); |
| return; |
| } |
| } |
| |
| inc = ipv6_addr_is_multicast(daddr); |
| |
| if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) { |
| |
| if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) { |
| if (dad) { |
| if (dev->type == ARPHRD_IEEE802_TR) { |
| const unsigned char *sadr; |
| sadr = skb_mac_header(skb); |
| if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 && |
| sadr[9] == dev->dev_addr[1] && |
| sadr[10] == dev->dev_addr[2] && |
| sadr[11] == dev->dev_addr[3] && |
| sadr[12] == dev->dev_addr[4] && |
| sadr[13] == dev->dev_addr[5]) { |
| /* looped-back to us */ |
| goto out; |
| } |
| } |
| |
| /* |
| * 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 { |
| idev = in6_dev_get(dev); |
| if (!idev) { |
| /* XXX: count this drop? */ |
| return; |
| } |
| |
| if (ipv6_chk_acast_addr(dev, &msg->target) || |
| (idev->cnf.forwarding && |
| (ipv6_devconf.proxy_ndp || idev->cnf.proxy_ndp) && |
| (pneigh = pneigh_lookup(&nd_tbl, |
| &msg->target, dev, 0)) != NULL)) { |
| if (!(NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED) && |
| skb->pkt_type != PACKET_HOST && |
| inc != 0 && |
| 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; |
| } |
| |
| is_router = !!(pneigh ? pneigh->flags & NTF_ROUTER : idev->cnf.forwarding); |
| |
| if (dad) { |
| struct in6_addr maddr; |
| |
| ipv6_addr_all_nodes(&maddr); |
| ndisc_send_na(dev, NULL, &maddr, &msg->target, |
| is_router, 0, (ifp != NULL), 1); |
| 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, neigh, saddr, &msg->target, |
| is_router, |
| 1, (ifp != NULL && inc), inc); |
| if (neigh) |
| neigh_release(neigh); |
| } |
| |
| out: |
| if (ifp) |
| in6_ifa_put(ifp); |
| else |
| in6_dev_put(idev); |
| |
| return; |
| } |
| |
| 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; |
| struct in6_addr *daddr = &ipv6_hdr(skb)->daddr; |
| u8 *lladdr = NULL; |
| u32 ndoptlen = skb->tail - (skb->transport_header + |
| 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_PRINTK2(KERN_WARNING |
| "ICMPv6 NA: packet too short\n"); |
| return; |
| } |
| |
| if (ipv6_addr_is_multicast(&msg->target)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 NA: target address is multicast.\n"); |
| return; |
| } |
| |
| if (ipv6_addr_is_multicast(daddr) && |
| msg->icmph.icmp6_solicited) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 NA: solicited NA is multicasted.\n"); |
| return; |
| } |
| |
| if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 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_PRINTK2(KERN_WARNING |
| "ICMPv6 NA: invalid link-layer address length\n"); |
| return; |
| } |
| } |
| if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1))) { |
| if (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 :-) |
| */ |
| ND_PRINTK1(KERN_WARNING |
| "ICMPv6 NA: someone advertises our address on %s!\n", |
| ifp->idev->dev->name); |
| in6_ifa_put(ifp); |
| return; |
| } |
| neigh = neigh_lookup(&nd_tbl, &msg->target, dev); |
| |
| if (neigh) { |
| u8 old_flags = neigh->flags; |
| |
| 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) && |
| ipv6_devconf.forwarding && ipv6_devconf.proxy_ndp && |
| pneigh_lookup(&nd_tbl, &msg->target, dev, 0)) { |
| /* XXX: idev->cnf.prixy_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 |
| */ |
| struct rt6_info *rt; |
| rt = rt6_get_dflt_router(saddr, dev); |
| if (rt) |
| ip6_del_rt(rt); |
| } |
| |
| 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; |
| 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) { |
| if (net_ratelimit()) |
| ND_PRINTK1("ICMP6 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)) { |
| if (net_ratelimit()) |
| ND_PRINTK2("ICMP6 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: |
| in6_dev_put(idev); |
| } |
| |
| 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; |
| |
| __u8 * opt = (__u8 *)(ra_msg + 1); |
| |
| optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg); |
| |
| if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 RA: source address is not link-local.\n"); |
| return; |
| } |
| if (optlen < 0) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 RA: packet too short\n"); |
| return; |
| } |
| |
| /* |
| * set the RA_RECV flag in the interface |
| */ |
| |
| in6_dev = in6_dev_get(skb->dev); |
| if (in6_dev == NULL) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 RA: can't find inet6 device for %s.\n", |
| skb->dev->name); |
| return; |
| } |
| if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_ra) { |
| in6_dev_put(in6_dev); |
| return; |
| } |
| |
| if (!ndisc_parse_options(opt, optlen, &ndopts)) { |
| in6_dev_put(in6_dev); |
| ND_PRINTK2(KERN_WARNING |
| "ICMP6 RA: invalid ND options\n"); |
| return; |
| } |
| |
| 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 |
| */ |
| 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 (!in6_dev->cnf.accept_ra_defrtr) |
| 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 = rt->rt6i_nexthop; |
| |
| if (rt && lifetime == 0) { |
| neigh_clone(neigh); |
| ip6_del_rt(rt); |
| rt = NULL; |
| } |
| |
| if (rt == NULL && lifetime) { |
| ND_PRINTK3(KERN_DEBUG |
| "ICMPv6 RA: adding default router.\n"); |
| |
| rt = rt6_add_dflt_router(&ipv6_hdr(skb)->saddr, skb->dev, pref); |
| if (rt == NULL) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 RA: %s() failed to add default route.\n", |
| __FUNCTION__); |
| in6_dev_put(in6_dev); |
| return; |
| } |
| |
| neigh = rt->rt6i_nexthop; |
| if (neigh == NULL) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 RA: %s() got default router without neighbour.\n", |
| __FUNCTION__); |
| dst_release(&rt->u.dst); |
| in6_dev_put(in6_dev); |
| return; |
| } |
| neigh->flags |= NTF_ROUTER; |
| } else if (rt) { |
| rt->rt6i_flags |= (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref); |
| } |
| |
| if (rt) |
| rt->rt6i_expires = jiffies + (HZ * lifetime); |
| |
| if (ra_msg->icmph.icmp6_hop_limit) { |
| in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit; |
| if (rt) |
| rt->u.dst.metrics[RTAX_HOPLIMIT-1] = ra_msg->icmph.icmp6_hop_limit; |
| } |
| |
| 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; |
| in6_dev->nd_parms->retrans_time = rtime; |
| in6_dev->tstamp = jiffies; |
| inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); |
| } |
| |
| 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 != in6_dev->nd_parms->base_reachable_time) { |
| in6_dev->nd_parms->base_reachable_time = rtime; |
| in6_dev->nd_parms->gc_staletime = 3 * rtime; |
| in6_dev->nd_parms->reachable_time = neigh_rand_reach_time(rtime); |
| in6_dev->tstamp = jiffies; |
| inet6_ifinfo_notify(RTM_NEWLINK, in6_dev); |
| } |
| } |
| } |
| |
| /* |
| * 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_PRINTK2(KERN_WARNING |
| "ICMPv6 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); |
| } |
| |
| #ifdef CONFIG_IPV6_ROUTE_INFO |
| 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)) { |
| if (((struct route_info *)p)->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); |
| } |
| } |
| #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); |
| } |
| } |
| |
| if (ndopts.nd_opts_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_PRINTK2(KERN_WARNING |
| "ICMPv6 RA: invalid mtu: %d\n", |
| mtu); |
| } else if (in6_dev->cnf.mtu6 != mtu) { |
| in6_dev->cnf.mtu6 = mtu; |
| |
| if (rt) |
| rt->u.dst.metrics[RTAX_MTU-1] = mtu; |
| |
| rt6_mtu_change(skb->dev, mtu); |
| } |
| } |
| |
| if (ndopts.nd_opts_tgt_lladdr || ndopts.nd_opts_rh) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 RA: invalid RA options"); |
| } |
| out: |
| if (rt) |
| dst_release(&rt->u.dst); |
| else if (neigh) |
| neigh_release(neigh); |
| in6_dev_put(in6_dev); |
| } |
| |
| static void ndisc_redirect_rcv(struct sk_buff *skb) |
| { |
| struct inet6_dev *in6_dev; |
| struct icmp6hdr *icmph; |
| struct in6_addr *dest; |
| struct in6_addr *target; /* new first hop to destination */ |
| struct neighbour *neigh; |
| int on_link = 0; |
| struct ndisc_options ndopts; |
| int optlen; |
| u8 *lladdr = NULL; |
| |
| if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: source address is not link-local.\n"); |
| return; |
| } |
| |
| optlen = skb->tail - skb->transport_header; |
| optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr); |
| |
| if (optlen < 0) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: packet too short\n"); |
| return; |
| } |
| |
| icmph = icmp6_hdr(skb); |
| target = (struct in6_addr *) (icmph + 1); |
| dest = target + 1; |
| |
| if (ipv6_addr_is_multicast(dest)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: destination address is multicast.\n"); |
| return; |
| } |
| |
| if (ipv6_addr_equal(dest, target)) { |
| on_link = 1; |
| } else if (ipv6_addr_type(target) != |
| (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: target address is not link-local unicast.\n"); |
| return; |
| } |
| |
| in6_dev = in6_dev_get(skb->dev); |
| if (!in6_dev) |
| return; |
| if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects) { |
| in6_dev_put(in6_dev); |
| return; |
| } |
| |
| /* RFC2461 8.1: |
| * The IP source address of the Redirect MUST be the same as the current |
| * first-hop router for the specified ICMP Destination Address. |
| */ |
| |
| if (!ndisc_parse_options((u8*)(dest + 1), optlen, &ndopts)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: invalid ND options\n"); |
| in6_dev_put(in6_dev); |
| return; |
| } |
| if (ndopts.nd_opts_tgt_lladdr) { |
| lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr, |
| skb->dev); |
| if (!lladdr) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: invalid link-layer address length\n"); |
| in6_dev_put(in6_dev); |
| return; |
| } |
| } |
| |
| neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1); |
| if (neigh) { |
| rt6_redirect(dest, &ipv6_hdr(skb)->daddr, |
| &ipv6_hdr(skb)->saddr, neigh, lladdr, |
| on_link); |
| neigh_release(neigh); |
| } |
| in6_dev_put(in6_dev); |
| } |
| |
| void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh, |
| struct in6_addr *target) |
| { |
| struct sock *sk = ndisc_socket->sk; |
| int len = sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr); |
| struct sk_buff *buff; |
| struct icmp6hdr *icmph; |
| struct in6_addr saddr_buf; |
| struct in6_addr *addrp; |
| struct net_device *dev; |
| struct rt6_info *rt; |
| struct dst_entry *dst; |
| struct inet6_dev *idev; |
| struct flowi fl; |
| u8 *opt; |
| int rd_len; |
| int err; |
| int hlen; |
| u8 ha_buf[MAX_ADDR_LEN], *ha = NULL; |
| |
| dev = skb->dev; |
| |
| if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 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_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: target address is not link-local unicast.\n"); |
| return; |
| } |
| |
| ndisc_flow_init(&fl, NDISC_REDIRECT, &saddr_buf, &ipv6_hdr(skb)->saddr, |
| dev->ifindex); |
| |
| dst = ip6_route_output(NULL, &fl); |
| if (dst == NULL) |
| return; |
| |
| err = xfrm_lookup(&dst, &fl, NULL, 0); |
| if (err) |
| return; |
| |
| rt = (struct rt6_info *) dst; |
| |
| if (rt->rt6i_flags & RTF_GATEWAY) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 Redirect: destination is not a neighbour.\n"); |
| dst_release(dst); |
| return; |
| } |
| if (!xrlim_allow(dst, 1*HZ)) { |
| dst_release(dst); |
| return; |
| } |
| |
| if (dev->addr_len) { |
| 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; |
| len += ndisc_opt_addr_space(dev); |
| } else |
| read_unlock_bh(&neigh->lock); |
| } |
| |
| rd_len = min_t(unsigned int, |
| IPV6_MIN_MTU-sizeof(struct ipv6hdr)-len, skb->len + 8); |
| rd_len &= ~0x7; |
| len += rd_len; |
| |
| buff = sock_alloc_send_skb(sk, |
| (MAX_HEADER + sizeof(struct ipv6hdr) + |
| len + LL_RESERVED_SPACE(dev)), |
| 1, &err); |
| if (buff == NULL) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 Redirect: %s() failed to allocate an skb.\n", |
| __FUNCTION__); |
| dst_release(dst); |
| return; |
| } |
| |
| hlen = 0; |
| |
| skb_reserve(buff, LL_RESERVED_SPACE(dev)); |
| ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr, |
| IPPROTO_ICMPV6, len); |
| |
| skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data); |
| skb_put(buff, len); |
| icmph = icmp6_hdr(buff); |
| |
| memset(icmph, 0, sizeof(struct icmp6hdr)); |
| icmph->icmp6_type = NDISC_REDIRECT; |
| |
| /* |
| * copy target and destination addresses |
| */ |
| |
| addrp = (struct in6_addr *)(icmph + 1); |
| ipv6_addr_copy(addrp, target); |
| addrp++; |
| ipv6_addr_copy(addrp, &ipv6_hdr(skb)->daddr); |
| |
| opt = (u8*) (addrp + 1); |
| |
| /* |
| * include target_address option |
| */ |
| |
| if (ha) |
| opt = ndisc_fill_addr_option(opt, ND_OPT_TARGET_LL_ADDR, ha, |
| dev->addr_len, dev->type); |
| |
| /* |
| * build redirect option and copy skb over to the new packet. |
| */ |
| |
| memset(opt, 0, 8); |
| *(opt++) = ND_OPT_REDIRECT_HDR; |
| *(opt++) = (rd_len >> 3); |
| opt += 6; |
| |
| memcpy(opt, ipv6_hdr(skb), rd_len - 8); |
| |
| icmph->icmp6_cksum = csum_ipv6_magic(&saddr_buf, &ipv6_hdr(skb)->saddr, |
| len, IPPROTO_ICMPV6, |
| csum_partial((u8 *) icmph, len, 0)); |
| |
| buff->dst = dst; |
| idev = in6_dev_get(dst->dev); |
| IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS); |
| err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, buff, NULL, dst->dev, dst_output); |
| if (!err) { |
| ICMP6MSGOUT_INC_STATS(idev, NDISC_REDIRECT); |
| ICMP6_INC_STATS(idev, ICMP6_MIB_OUTMSGS); |
| } |
| |
| if (likely(idev != NULL)) |
| in6_dev_put(idev); |
| } |
| |
| static void pndisc_redo(struct sk_buff *skb) |
| { |
| ndisc_recv_ns(skb); |
| kfree_skb(skb); |
| } |
| |
| int ndisc_rcv(struct sk_buff *skb) |
| { |
| struct nd_msg *msg; |
| |
| if (!pskb_may_pull(skb, skb->len)) |
| 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_PRINTK2(KERN_WARNING |
| "ICMPv6 NDISC: invalid hop-limit: %d\n", |
| ipv6_hdr(skb)->hop_limit); |
| return 0; |
| } |
| |
| if (msg->icmph.icmp6_code != 0) { |
| ND_PRINTK2(KERN_WARNING |
| "ICMPv6 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 = ptr; |
| |
| if (dev->nd_net != &init_net) |
| return NOTIFY_DONE; |
| |
| switch (event) { |
| case NETDEV_CHANGEADDR: |
| neigh_changeaddr(&nd_tbl, dev); |
| fib6_run_gc(~0UL); |
| break; |
| case NETDEV_DOWN: |
| neigh_ifdown(&nd_tbl, dev); |
| fib6_run_gc(~0UL); |
| 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); |
| printk(KERN_WARNING |
| "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, struct file * filp, void __user *buffer, size_t *lenp, loff_t *ppos) |
| { |
| struct net_device *dev = ctl->extra1; |
| struct inet6_dev *idev; |
| int ret; |
| |
| if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME || |
| ctl->ctl_name == NET_NEIGH_REACHABLE_TIME) |
| ndisc_warn_deprecated_sysctl(ctl, "syscall", dev ? dev->name : "default"); |
| |
| switch (ctl->ctl_name) { |
| case NET_NEIGH_RETRANS_TIME: |
| ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos); |
| break; |
| case NET_NEIGH_REACHABLE_TIME: |
| ret = proc_dointvec_jiffies(ctl, write, |
| filp, buffer, lenp, ppos); |
| break; |
| case NET_NEIGH_RETRANS_TIME_MS: |
| case NET_NEIGH_REACHABLE_TIME_MS: |
| ret = proc_dointvec_ms_jiffies(ctl, write, |
| filp, buffer, lenp, ppos); |
| break; |
| default: |
| ret = -1; |
| } |
| |
| if (write && ret == 0 && dev && (idev = in6_dev_get(dev)) != NULL) { |
| if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME || |
| ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS) |
| idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time); |
| idev->tstamp = jiffies; |
| inet6_ifinfo_notify(RTM_NEWLINK, idev); |
| in6_dev_put(idev); |
| } |
| return ret; |
| } |
| |
| static int ndisc_ifinfo_sysctl_strategy(ctl_table *ctl, int __user *name, |
| int nlen, void __user *oldval, |
| size_t __user *oldlenp, |
| void __user *newval, size_t newlen) |
| { |
| struct net_device *dev = ctl->extra1; |
| struct inet6_dev *idev; |
| int ret; |
| |
| if (ctl->ctl_name == NET_NEIGH_RETRANS_TIME || |
| ctl->ctl_name == NET_NEIGH_REACHABLE_TIME) |
| ndisc_warn_deprecated_sysctl(ctl, "procfs", dev ? dev->name : "default"); |
| |
| switch (ctl->ctl_name) { |
| case NET_NEIGH_REACHABLE_TIME: |
| ret = sysctl_jiffies(ctl, name, nlen, |
| oldval, oldlenp, newval, newlen); |
| break; |
| case NET_NEIGH_RETRANS_TIME_MS: |
| case NET_NEIGH_REACHABLE_TIME_MS: |
| ret = sysctl_ms_jiffies(ctl, name, nlen, |
| oldval, oldlenp, newval, newlen); |
| break; |
| default: |
| ret = 0; |
| } |
| |
| if (newval && newlen && ret > 0 && |
| dev && (idev = in6_dev_get(dev)) != NULL) { |
| if (ctl->ctl_name == NET_NEIGH_REACHABLE_TIME || |
| ctl->ctl_name == NET_NEIGH_REACHABLE_TIME_MS) |
| idev->nd_parms->reachable_time = neigh_rand_reach_time(idev->nd_parms->base_reachable_time); |
| idev->tstamp = jiffies; |
| inet6_ifinfo_notify(RTM_NEWLINK, idev); |
| in6_dev_put(idev); |
| } |
| |
| return ret; |
| } |
| |
| #endif |
| |
| int __init ndisc_init(struct net_proto_family *ops) |
| { |
| struct ipv6_pinfo *np; |
| struct sock *sk; |
| int err; |
| |
| err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6, &ndisc_socket); |
| if (err < 0) { |
| ND_PRINTK0(KERN_ERR |
| "ICMPv6 NDISC: Failed to initialize the control socket (err %d).\n", |
| err); |
| ndisc_socket = NULL; /* For safety. */ |
| return err; |
| } |
| |
| sk = ndisc_socket->sk; |
| np = inet6_sk(sk); |
| sk->sk_allocation = GFP_ATOMIC; |
| np->hop_limit = 255; |
| /* Do not loopback ndisc messages */ |
| np->mc_loop = 0; |
| sk->sk_prot->unhash(sk); |
| |
| /* |
| * Initialize the neighbour table |
| */ |
| |
| neigh_table_init(&nd_tbl); |
| |
| #ifdef CONFIG_SYSCTL |
| neigh_sysctl_register(NULL, &nd_tbl.parms, NET_IPV6, NET_IPV6_NEIGH, |
| "ipv6", |
| &ndisc_ifinfo_sysctl_change, |
| &ndisc_ifinfo_sysctl_strategy); |
| #endif |
| |
| register_netdevice_notifier(&ndisc_netdev_notifier); |
| return 0; |
| } |
| |
| void ndisc_cleanup(void) |
| { |
| unregister_netdevice_notifier(&ndisc_netdev_notifier); |
| #ifdef CONFIG_SYSCTL |
| neigh_sysctl_unregister(&nd_tbl.parms); |
| #endif |
| neigh_table_clear(&nd_tbl); |
| sock_release(ndisc_socket); |
| ndisc_socket = NULL; /* For safety. */ |
| } |