// SPDX-License-Identifier: GPL-2.0-or-later/* * IPv6 input * Linux INET6 implementation * * Authors: * Pedro Roque <roque@di.fc.ul.pt> * Ian P. Morris <I.P.Morris@soton.ac.uk> * * Based in linux/net/ipv4/ip_input.c *//* Changes * * Mitsuru KANDA @USAGI and * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs(). */ #include <linux/errno.h>#include <linux/types.h>#include <linux/socket.h>#include <linux/sockios.h>#include <linux/net.h>#include <linux/netdevice.h>#include <linux/in6.h>#include <linux/icmpv6.h>#include <linux/mroute6.h>#include <linux/slab.h>#include <linux/indirect_call_wrapper.h> #include <linux/netfilter.h>#include <linux/netfilter_ipv6.h> #include <net/sock.h>#include <net/snmp.h>#include <net/udp.h> #include <net/ipv6.h>#include <net/protocol.h>#include <net/transp_v6.h>#include <net/rawv6.h>#include <net/ndisc.h>#include <net/ip6_route.h>#include <net/addrconf.h>#include <net/xfrm.h>#include <net/inet_ecn.h>#include <net/dst_metadata.h>#include <net/inet6_hashtables.h> static void tcp_v6_early_demux(struct sk_buff *skb){ struct net *net = dev_net_rcu(skb->dev); const struct ipv6hdr *hdr; const struct tcphdr *th; struct sock *sk; if (skb->pkt_type != PACKET_HOST) return; if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) return; hdr = ipv6_hdr(skb); th = tcp_hdr(skb); if (th->doff < sizeof(struct tcphdr) / 4) return; /* Note : We use inet6_iif() here, not tcp_v6_iif() */ sk = __inet6_lookup_established(net, &hdr->saddr, th->source, &hdr->daddr, ntohs(th->dest), inet6_iif(skb), inet6_sdif(skb)); if (sk) { skb->sk = sk; skb->destructor = sock_edemux; if (sk_fullsock(sk)) { struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst); if (dst) dst = dst_check(dst, sk->sk_rx_dst_cookie); if (dst && sk->sk_rx_dst_ifindex == skb->skb_iif) skb_dst_set_noref(skb, dst); } }} static void ip6_rcv_finish_core(struct net *net, struct sock *sk, struct sk_buff *skb){ if (READ_ONCE(net->ipv4.sysctl_ip_early_demux) && !skb_dst(skb) && !skb->sk) { switch (ipv6_hdr(skb)->nexthdr) { case IPPROTO_TCP: if (READ_ONCE(net->ipv4.sysctl_tcp_early_demux)) tcp_v6_early_demux(skb); break; case IPPROTO_UDP: if (READ_ONCE(net->ipv4.sysctl_udp_early_demux)) udp_v6_early_demux(skb); break; } } if (!skb_valid_dst(skb)) ip6_route_input(skb);} int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb){ /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip6_rcv(skb); if (!skb) return NET_RX_SUCCESS; ip6_rcv_finish_core(net, sk, skb); return dst_input(skb);} static void ip6_sublist_rcv_finish(struct list_head *head){ struct sk_buff *skb, *next; list_for_each_entry_safe(skb, next, head, list) { skb_list_del_init(skb); dst_input(skb); }} static bool ip6_can_use_hint(const struct sk_buff *skb, const struct sk_buff *hint){ return hint && !skb_dst(skb) && ipv6_addr_equal(&ipv6_hdr(hint)->daddr, &ipv6_hdr(skb)->daddr);} static struct sk_buff *ip6_extract_route_hint(const struct net *net, struct sk_buff *skb){ if (fib6_routes_require_src(net) || fib6_has_custom_rules(net) || IP6CB(skb)->flags & IP6SKB_MULTIPATH) return NULL; return skb;} static void ip6_list_rcv_finish(struct net *net, struct sock *sk, struct list_head *head){ struct sk_buff *skb, *next, *hint = NULL; struct dst_entry *curr_dst = NULL; LIST_HEAD(sublist); list_for_each_entry_safe(skb, next, head, list) { struct dst_entry *dst; skb_list_del_init(skb); /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip6_rcv(skb); if (!skb) continue; if (ip6_can_use_hint(skb, hint)) skb_dst_copy(skb, hint); else ip6_rcv_finish_core(net, sk, skb); dst = skb_dst(skb); if (curr_dst != dst) { hint = ip6_extract_route_hint(net, skb); /* dispatch old sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv_finish(&sublist); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dst = dst; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ ip6_sublist_rcv_finish(&sublist);} static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, struct net *net){ enum skb_drop_reason reason; const struct ipv6hdr *hdr; u32 pkt_len; struct inet6_dev *idev; if (skb->pkt_type == PACKET_OTHERHOST) { dev_core_stats_rx_otherhost_dropped_inc(skb->dev); kfree_skb_reason(skb, SKB_DROP_REASON_OTHERHOST); return NULL; } rcu_read_lock(); idev = __in6_dev_get(skb->dev); __IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_IN, skb->len); SKB_DR_SET(reason, NOT_SPECIFIED); if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL || !idev || unlikely(READ_ONCE(idev->cnf.disable_ipv6))) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); if (idev && unlikely(READ_ONCE(idev->cnf.disable_ipv6))) SKB_DR_SET(reason, IPV6DISABLED); goto drop; } memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); /* * Store incoming device index. When the packet will * be queued, we cannot refer to skb->dev anymore. * * BTW, when we send a packet for our own local address on a * non-loopback interface (e.g. ethX), it is being delivered * via the loopback interface (lo) here; skb->dev = loopback_dev. * It, however, should be considered as if it is being * arrived via the sending interface (ethX), because of the * nature of scoping architecture. --yoshfuji */ IP6CB(skb)->iif = skb_valid_dst(skb) ? ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex; if (unlikely(!pskb_may_pull(skb, sizeof(*hdr)))) goto err; hdr = ipv6_hdr(skb); if (hdr->version != 6) { SKB_DR_SET(reason, UNHANDLED_PROTO); goto err; } __IP6_ADD_STATS(net, idev, IPSTATS_MIB_NOECTPKTS + (ipv6_get_dsfield(hdr) & INET_ECN_MASK), max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); /* * RFC4291 2.5.3 * The loopback address must not be used as the source address in IPv6 * packets that are sent outside of a single node. [..] * A packet received on an interface with a destination address * of loopback must be dropped. */ if ((ipv6_addr_loopback(&hdr->saddr) || ipv6_addr_loopback(&hdr->daddr)) && !(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev)) goto err; /* RFC4291 Errata ID: 3480 * Interface-Local scope spans only a single interface on a * node and is useful only for loopback transmission of * multicast. Packets with interface-local scope received * from another node must be discarded. */ if (!(skb->pkt_type == PACKET_LOOPBACK || dev->flags & IFF_LOOPBACK) && ipv6_addr_is_multicast(&hdr->daddr) && IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 1) goto err; /* If enabled, drop unicast packets that were encapsulated in link-layer * multicast or broadcast to protected against the so-called "hole-196" * attack in 802.11 wireless. */ if (!ipv6_addr_is_multicast(&hdr->daddr) && (skb->pkt_type == PACKET_BROADCAST || skb->pkt_type == PACKET_MULTICAST) && READ_ONCE(idev->cnf.drop_unicast_in_l2_multicast)) { SKB_DR_SET(reason, UNICAST_IN_L2_MULTICAST); goto err; } /* RFC4291 2.7 * Nodes must not originate a packet to a multicast address whose scope * field contains the reserved value 0; if such a packet is received, it * must be silently dropped. */ if (ipv6_addr_is_multicast(&hdr->daddr) && IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 0) goto err; /* * RFC4291 2.7 * Multicast addresses must not be used as source addresses in IPv6 * packets or appear in any Routing header. */ if (ipv6_addr_is_multicast(&hdr->saddr)) goto err; skb->transport_header = skb->network_header + sizeof(*hdr); IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); pkt_len = ipv6_payload_len(skb, hdr); /* pkt_len may be zero if Jumbo payload option is present */ if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { if (pkt_len + sizeof(struct ipv6hdr) > skb->len) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INTRUNCATEDPKTS); SKB_DR_SET(reason, PKT_TOO_SMALL); goto drop; } if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) goto err; hdr = ipv6_hdr(skb); } if (hdr->nexthdr == NEXTHDR_HOP) { if (ipv6_parse_hopopts(skb) < 0) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); rcu_read_unlock(); return NULL; } } rcu_read_unlock(); /* Must drop socket now because of tproxy. */ if (!skb_sk_is_prefetched(skb)) skb_orphan(skb); return skb;err: __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); SKB_DR_OR(reason, IP_INHDR);drop: rcu_read_unlock(); kfree_skb_reason(skb, reason); return NULL;} int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev){ struct net *net = dev_net(skb->dev); skb = ip6_rcv_core(skb, dev, net); if (skb == NULL) return NET_RX_DROP; return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, net, NULL, skb, dev, NULL, ip6_rcv_finish);} static void ip6_sublist_rcv(struct list_head *head, struct net_device *dev, struct net *net){ NF_HOOK_LIST(NFPROTO_IPV6, NF_INET_PRE_ROUTING, net, NULL, head, dev, NULL, ip6_rcv_finish); ip6_list_rcv_finish(net, NULL, head);} /* Receive a list of IPv6 packets */void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, struct net_device *orig_dev){ struct net_device *curr_dev = NULL; struct net *curr_net = NULL; struct sk_buff *skb, *next; LIST_HEAD(sublist); list_for_each_entry_safe(skb, next, head, list) { struct net_device *dev = skb->dev; struct net *net = dev_net(dev); skb_list_del_init(skb); skb = ip6_rcv_core(skb, dev, net); if (skb == NULL) continue; if (curr_dev != dev || curr_net != net) { /* dispatch old sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv(&sublist, curr_dev, curr_net); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dev = dev; curr_net = net; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv(&sublist, curr_dev, curr_net);} INDIRECT_CALLABLE_DECLARE(int tcp_v6_rcv(struct sk_buff *)); /* * Deliver the packet to the host */void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr, bool have_final){ int exthdr_cnt = IP6CB(skb)->flags & IP6SKB_HOPBYHOP ? 1 : 0; const struct inet6_protocol *ipprot; struct inet6_dev *idev; unsigned int nhoff; SKB_DR(reason); bool raw; /* * Parse extension headers */ resubmit: idev = ip6_dst_idev(skb_dst(skb)); nhoff = IP6CB(skb)->nhoff; if (!have_final) { if (!pskb_pull(skb, skb_transport_offset(skb))) goto discard; nexthdr = skb_network_header(skb)[nhoff]; } resubmit_final: raw = raw6_local_deliver(skb, nexthdr); ipprot = rcu_dereference(inet6_protos[nexthdr]); if (ipprot) { int ret; if (have_final) { if (!(ipprot->flags & INET6_PROTO_FINAL)) { /* Once we've seen a final protocol don't * allow encapsulation on any non-final * ones. This allows foo in UDP encapsulation * to work. */ goto discard; } } else if (ipprot->flags & INET6_PROTO_FINAL) { const struct ipv6hdr *hdr; int sdif = inet6_sdif(skb); struct net_device *dev; /* Only do this once for first final protocol */ have_final = true; skb_postpull_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); hdr = ipv6_hdr(skb); /* skb->dev passed may be master dev for vrfs. */ if (sdif) { dev = dev_get_by_index_rcu(net, sdif); if (!dev) goto discard; } else { dev = skb->dev; } if (ipv6_addr_is_multicast(&hdr->daddr) && !ipv6_chk_mcast_addr(dev, &hdr->daddr, &hdr->saddr) && !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb))) { SKB_DR_SET(reason, IP_INADDRERRORS); goto discard; } } if (!(ipprot->flags & INET6_PROTO_NOPOLICY)) { if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { SKB_DR_SET(reason, XFRM_POLICY); goto discard; } nf_reset_ct(skb); } ret = INDIRECT_CALL_2(ipprot->handler, tcp_v6_rcv, udpv6_rcv, skb); if (ret > 0) { if (ipprot->flags & INET6_PROTO_FINAL) { /* Not an extension header, most likely UDP * encapsulation. Use return value as nexthdr * protocol not nhoff (which presumably is * not set by handler). */ nexthdr = ret; goto resubmit_final; } else { if (unlikely(exthdr_cnt++ >= IP6_MAX_EXT_HDRS_CNT)) { SKB_DR_SET(reason, IPV6_TOO_MANY_EXTHDRS); goto discard; } goto resubmit; } } else if (ret == 0) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDELIVERS); } } else {Lines 1–500 of 643. Load more
// SPDX-License-Identifier: GPL-2.0-or-later /* * IPv6 input * Linux INET6 implementation * * Authors: * Pedro Roque <roque@di.fc.ul.pt> * Ian P. Morris <I.P.Morris@soton.ac.uk> * * Based in linux/net/ipv4/ip_input.c */ /* Changes * * Mitsuru KANDA @USAGI and * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs(). */ #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/net.h> #include <linux/netdevice.h> #include <linux/in6.h> #include <linux/icmpv6.h> #include <linux/mroute6.h> #include <linux/slab.h> #include <linux/indirect_call_wrapper.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv6.h> #include <net/sock.h> #include <net/snmp.h> #include <net/udp.h> #include <net/ipv6.h> #include <net/protocol.h> #include <net/transp_v6.h> #include <net/rawv6.h> #include <net/ndisc.h> #include <net/ip6_route.h> #include <net/addrconf.h> #include <net/xfrm.h> #include <net/inet_ecn.h> #include <net/dst_metadata.h> #include <net/inet6_hashtables.h> static void tcp_v6_early_demux(struct sk_buff *skb) { struct net *net = dev_net_rcu(skb->dev); const struct ipv6hdr *hdr; const struct tcphdr *th; struct sock *sk; if (skb->pkt_type != PACKET_HOST) return; if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr))) return; hdr = ipv6_hdr(skb); th = tcp_hdr(skb); if (th->doff < sizeof(struct tcphdr) / 4) return; /* Note : We use inet6_iif() here, not tcp_v6_iif() */ sk = __inet6_lookup_established(net, &hdr->saddr, th->source, &hdr->daddr, ntohs(th->dest), inet6_iif(skb), inet6_sdif(skb)); if (sk) { skb->sk = sk; skb->destructor = sock_edemux; if (sk_fullsock(sk)) { struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst); if (dst) dst = dst_check(dst, sk->sk_rx_dst_cookie); if (dst && sk->sk_rx_dst_ifindex == skb->skb_iif) skb_dst_set_noref(skb, dst); } } } static void ip6_rcv_finish_core(struct net *net, struct sock *sk, struct sk_buff *skb) { if (READ_ONCE(net->ipv4.sysctl_ip_early_demux) && !skb_dst(skb) && !skb->sk) { switch (ipv6_hdr(skb)->nexthdr) { case IPPROTO_TCP: if (READ_ONCE(net->ipv4.sysctl_tcp_early_demux)) tcp_v6_early_demux(skb); break; case IPPROTO_UDP: if (READ_ONCE(net->ipv4.sysctl_udp_early_demux)) udp_v6_early_demux(skb); break; } } if (!skb_valid_dst(skb)) ip6_route_input(skb); } int ip6_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) { /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip6_rcv(skb); if (!skb) return NET_RX_SUCCESS; ip6_rcv_finish_core(net, sk, skb); return dst_input(skb); } static void ip6_sublist_rcv_finish(struct list_head *head) { struct sk_buff *skb, *next; list_for_each_entry_safe(skb, next, head, list) { skb_list_del_init(skb); dst_input(skb); } } static bool ip6_can_use_hint(const struct sk_buff *skb, const struct sk_buff *hint) { return hint && !skb_dst(skb) && ipv6_addr_equal(&ipv6_hdr(hint)->daddr, &ipv6_hdr(skb)->daddr); } static struct sk_buff *ip6_extract_route_hint(const struct net *net, struct sk_buff *skb) { if (fib6_routes_require_src(net) || fib6_has_custom_rules(net) || IP6CB(skb)->flags & IP6SKB_MULTIPATH) return NULL; return skb; } static void ip6_list_rcv_finish(struct net *net, struct sock *sk, struct list_head *head) { struct sk_buff *skb, *next, *hint = NULL; struct dst_entry *curr_dst = NULL; LIST_HEAD(sublist); list_for_each_entry_safe(skb, next, head, list) { struct dst_entry *dst; skb_list_del_init(skb); /* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip6_rcv(skb); if (!skb) continue; if (ip6_can_use_hint(skb, hint)) skb_dst_copy(skb, hint); else ip6_rcv_finish_core(net, sk, skb); dst = skb_dst(skb); if (curr_dst != dst) { hint = ip6_extract_route_hint(net, skb); /* dispatch old sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv_finish(&sublist); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dst = dst; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ ip6_sublist_rcv_finish(&sublist); } static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, struct net *net) { enum skb_drop_reason reason; const struct ipv6hdr *hdr; u32 pkt_len; struct inet6_dev *idev; if (skb->pkt_type == PACKET_OTHERHOST) { dev_core_stats_rx_otherhost_dropped_inc(skb->dev); kfree_skb_reason(skb, SKB_DROP_REASON_OTHERHOST); return NULL; } rcu_read_lock(); idev = __in6_dev_get(skb->dev); __IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_IN, skb->len); SKB_DR_SET(reason, NOT_SPECIFIED); if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL || !idev || unlikely(READ_ONCE(idev->cnf.disable_ipv6))) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); if (idev && unlikely(READ_ONCE(idev->cnf.disable_ipv6))) SKB_DR_SET(reason, IPV6DISABLED); goto drop; } memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); /* * Store incoming device index. When the packet will * be queued, we cannot refer to skb->dev anymore. * * BTW, when we send a packet for our own local address on a * non-loopback interface (e.g. ethX), it is being delivered * via the loopback interface (lo) here; skb->dev = loopback_dev. * It, however, should be considered as if it is being * arrived via the sending interface (ethX), because of the * nature of scoping architecture. --yoshfuji */ IP6CB(skb)->iif = skb_valid_dst(skb) ? ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex; if (unlikely(!pskb_may_pull(skb, sizeof(*hdr)))) goto err; hdr = ipv6_hdr(skb); if (hdr->version != 6) { SKB_DR_SET(reason, UNHANDLED_PROTO); goto err; } __IP6_ADD_STATS(net, idev, IPSTATS_MIB_NOECTPKTS + (ipv6_get_dsfield(hdr) & INET_ECN_MASK), max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); /* * RFC4291 2.5.3 * The loopback address must not be used as the source address in IPv6 * packets that are sent outside of a single node. [..] * A packet received on an interface with a destination address * of loopback must be dropped. */ if ((ipv6_addr_loopback(&hdr->saddr) || ipv6_addr_loopback(&hdr->daddr)) && !(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev)) goto err; /* RFC4291 Errata ID: 3480 * Interface-Local scope spans only a single interface on a * node and is useful only for loopback transmission of * multicast. Packets with interface-local scope received * from another node must be discarded. */ if (!(skb->pkt_type == PACKET_LOOPBACK || dev->flags & IFF_LOOPBACK) && ipv6_addr_is_multicast(&hdr->daddr) && IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 1) goto err; /* If enabled, drop unicast packets that were encapsulated in link-layer * multicast or broadcast to protected against the so-called "hole-196" * attack in 802.11 wireless. */ if (!ipv6_addr_is_multicast(&hdr->daddr) && (skb->pkt_type == PACKET_BROADCAST || skb->pkt_type == PACKET_MULTICAST) && READ_ONCE(idev->cnf.drop_unicast_in_l2_multicast)) { SKB_DR_SET(reason, UNICAST_IN_L2_MULTICAST); goto err; } /* RFC4291 2.7 * Nodes must not originate a packet to a multicast address whose scope * field contains the reserved value 0; if such a packet is received, it * must be silently dropped. */ if (ipv6_addr_is_multicast(&hdr->daddr) && IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 0) goto err; /* * RFC4291 2.7 * Multicast addresses must not be used as source addresses in IPv6 * packets or appear in any Routing header. */ if (ipv6_addr_is_multicast(&hdr->saddr)) goto err; skb->transport_header = skb->network_header + sizeof(*hdr); IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); pkt_len = ipv6_payload_len(skb, hdr); /* pkt_len may be zero if Jumbo payload option is present */ if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { if (pkt_len + sizeof(struct ipv6hdr) > skb->len) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INTRUNCATEDPKTS); SKB_DR_SET(reason, PKT_TOO_SMALL); goto drop; } if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) goto err; hdr = ipv6_hdr(skb); } if (hdr->nexthdr == NEXTHDR_HOP) { if (ipv6_parse_hopopts(skb) < 0) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); rcu_read_unlock(); return NULL; } } rcu_read_unlock(); /* Must drop socket now because of tproxy. */ if (!skb_sk_is_prefetched(skb)) skb_orphan(skb); return skb; err: __IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS); SKB_DR_OR(reason, IP_INHDR); drop: rcu_read_unlock(); kfree_skb_reason(skb, reason); return NULL; } int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct net *net = dev_net(skb->dev); skb = ip6_rcv_core(skb, dev, net); if (skb == NULL) return NET_RX_DROP; return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, net, NULL, skb, dev, NULL, ip6_rcv_finish); } static void ip6_sublist_rcv(struct list_head *head, struct net_device *dev, struct net *net) { NF_HOOK_LIST(NFPROTO_IPV6, NF_INET_PRE_ROUTING, net, NULL, head, dev, NULL, ip6_rcv_finish); ip6_list_rcv_finish(net, NULL, head); } /* Receive a list of IPv6 packets */ void ipv6_list_rcv(struct list_head *head, struct packet_type *pt, struct net_device *orig_dev) { struct net_device *curr_dev = NULL; struct net *curr_net = NULL; struct sk_buff *skb, *next; LIST_HEAD(sublist); list_for_each_entry_safe(skb, next, head, list) { struct net_device *dev = skb->dev; struct net *net = dev_net(dev); skb_list_del_init(skb); skb = ip6_rcv_core(skb, dev, net); if (skb == NULL) continue; if (curr_dev != dev || curr_net != net) { /* dispatch old sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv(&sublist, curr_dev, curr_net); /* start new sublist */ INIT_LIST_HEAD(&sublist); curr_dev = dev; curr_net = net; } list_add_tail(&skb->list, &sublist); } /* dispatch final sublist */ if (!list_empty(&sublist)) ip6_sublist_rcv(&sublist, curr_dev, curr_net); } INDIRECT_CALLABLE_DECLARE(int tcp_v6_rcv(struct sk_buff *)); /* * Deliver the packet to the host */ void ip6_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int nexthdr, bool have_final) { int exthdr_cnt = IP6CB(skb)->flags & IP6SKB_HOPBYHOP ? 1 : 0; const struct inet6_protocol *ipprot; struct inet6_dev *idev; unsigned int nhoff; SKB_DR(reason); bool raw; /* * Parse extension headers */ resubmit: idev = ip6_dst_idev(skb_dst(skb)); nhoff = IP6CB(skb)->nhoff; if (!have_final) { if (!pskb_pull(skb, skb_transport_offset(skb))) goto discard; nexthdr = skb_network_header(skb)[nhoff]; } resubmit_final: raw = raw6_local_deliver(skb, nexthdr); ipprot = rcu_dereference(inet6_protos[nexthdr]); if (ipprot) { int ret; if (have_final) { if (!(ipprot->flags & INET6_PROTO_FINAL)) { /* Once we've seen a final protocol don't * allow encapsulation on any non-final * ones. This allows foo in UDP encapsulation * to work. */ goto discard; } } else if (ipprot->flags & INET6_PROTO_FINAL) { const struct ipv6hdr *hdr; int sdif = inet6_sdif(skb); struct net_device *dev; /* Only do this once for first final protocol */ have_final = true; skb_postpull_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); hdr = ipv6_hdr(skb); /* skb->dev passed may be master dev for vrfs. */ if (sdif) { dev = dev_get_by_index_rcu(net, sdif); if (!dev) goto discard; } else { dev = skb->dev; } if (ipv6_addr_is_multicast(&hdr->daddr) && !ipv6_chk_mcast_addr(dev, &hdr->daddr, &hdr->saddr) && !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb))) { SKB_DR_SET(reason, IP_INADDRERRORS); goto discard; } } if (!(ipprot->flags & INET6_PROTO_NOPOLICY)) { if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { SKB_DR_SET(reason, XFRM_POLICY); goto discard; } nf_reset_ct(skb); } ret = INDIRECT_CALL_2(ipprot->handler, tcp_v6_rcv, udpv6_rcv, skb); if (ret > 0) { if (ipprot->flags & INET6_PROTO_FINAL) { /* Not an extension header, most likely UDP * encapsulation. Use return value as nexthdr * protocol not nhoff (which presumably is * not set by handler). */ nexthdr = ret; goto resubmit_final; } else { if (unlikely(exthdr_cnt++ >= IP6_MAX_EXT_HDRS_CNT)) { SKB_DR_SET(reason, IPV6_TOO_MANY_EXTHDRS); goto discard; } goto resubmit; } } else if (ret == 0) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDELIVERS); } } else {