diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index e2d19694ee8f..8b7d28f3aada 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -26,6 +26,8 @@ struct nf_ipv6_ops { int (*chk_addr)(struct net *net, const struct in6_addr *addr, const struct net_device *dev, int strict); void (*route_input)(struct sk_buff *skb); + int (*fragment)(struct sock *sk, struct sk_buff *skb, + int (*output)(struct sock *, struct sk_buff *)); }; extern const struct nf_ipv6_ops __rcu *nf_ipv6_ops; diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index d201ea4440c9..535f9dae743e 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -34,6 +34,7 @@ #include #include +#include #include #include @@ -320,6 +321,55 @@ bad: return -1; } +/* Equivalent to br_validate_ipv4 for IPv6 */ +static int br_validate_ipv6(struct sk_buff *skb) +{ + const struct ipv6hdr *hdr; + struct net_device *dev = skb->dev; + struct inet6_dev *idev = in6_dev_get(skb->dev); + u32 pkt_len; + u8 ip6h_len = sizeof(struct ipv6hdr); + + if (!pskb_may_pull(skb, ip6h_len)) + goto inhdr_error; + + if (skb->len < ip6h_len) + goto drop; + + hdr = ipv6_hdr(skb); + + if (hdr->version != 6) + goto inhdr_error; + + pkt_len = ntohs(hdr->payload_len); + + if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { + if (pkt_len + ip6h_len > skb->len) { + IP6_INC_STATS_BH(dev_net(dev), idev, + IPSTATS_MIB_INTRUNCATEDPKTS); + goto drop; + } + if (pskb_trim_rcsum(skb, pkt_len + ip6h_len)) { + IP6_INC_STATS_BH(dev_net(dev), idev, + IPSTATS_MIB_INDISCARDS); + goto drop; + } + } + if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb)) + goto drop; + + memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); + /* No IP options in IPv6 header; however it should be + * checked if some next headers need special treatment + */ + return 0; + +inhdr_error: + IP6_INC_STATS_BH(dev_net(dev), idev, IPSTATS_MIB_INHDRERRORS); +drop: + return -1; +} + static void nf_bridge_update_protocol(struct sk_buff *skb) { switch (skb->nf_bridge->orig_proto) { @@ -405,6 +455,8 @@ static int br_nf_pre_routing_finish_ipv6(struct sock *sk, struct sk_buff *skb) struct net_device *dev = skb->dev; const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops(); + nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size; + if (nf_bridge->pkt_otherhost) { skb->pkt_type = PACKET_OTHERHOST; nf_bridge->pkt_otherhost = false; @@ -606,35 +658,15 @@ static struct net_device *setup_pre_routing(struct sk_buff *skb) } /* Replicate the checks that IPv6 does on packet reception and pass the packet - * to ip6tables, which doesn't support NAT, so things are fairly simple. */ + * to ip6tables. + */ static unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops, struct sk_buff *skb, const struct nf_hook_state *state) { struct nf_bridge_info *nf_bridge; - const struct ipv6hdr *hdr; - u32 pkt_len; - if (skb->len < sizeof(struct ipv6hdr)) - return NF_DROP; - - if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) - return NF_DROP; - - hdr = ipv6_hdr(skb); - - if (hdr->version != 6) - return NF_DROP; - - pkt_len = ntohs(hdr->payload_len); - - if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { - if (pkt_len + sizeof(struct ipv6hdr) > skb->len) - return NF_DROP; - if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) - return NF_DROP; - } - if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb)) + if (br_validate_ipv6(skb)) return NF_DROP; nf_bridge_put(skb->nf_bridge); @@ -738,9 +770,11 @@ static int br_nf_forward_finish(struct sock *sk, struct sk_buff *skb) if (!IS_ARP(skb) && !IS_VLAN_ARP(skb)) { - if (skb->protocol == htons(ETH_P_IP)) { + if (skb->protocol == htons(ETH_P_IP)) nf_bridge->frag_max_size = IPCB(skb)->frag_max_size; - } + + if (skb->protocol == htons(ETH_P_IPV6)) + nf_bridge->frag_max_size = IP6CB(skb)->frag_max_size; in = nf_bridge->physindev; if (nf_bridge->pkt_otherhost) { @@ -808,6 +842,12 @@ static unsigned int br_nf_forward_ip(const struct nf_hook_ops *ops, IPCB(skb)->frag_max_size = nf_bridge->frag_max_size; } + if (pf == NFPROTO_IPV6) { + if (br_validate_ipv6(skb)) + return NF_DROP; + IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size; + } + nf_bridge->physoutdev = skb->dev; if (pf == NFPROTO_IPV4) skb->protocol = htons(ETH_P_IP); @@ -855,7 +895,7 @@ static unsigned int br_nf_forward_arp(const struct nf_hook_ops *ops, return NF_STOLEN; } -#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) || IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) static int br_nf_push_frag_xmit(struct sock *sk, struct sk_buff *skb) { struct brnf_frag_data *data; @@ -875,6 +915,7 @@ static int br_nf_push_frag_xmit(struct sock *sk, struct sk_buff *skb) nf_bridge_info_free(skb); return br_dev_queue_push_xmit(sk, skb); } +#endif static int br_nf_ip_fragment(struct sock *sk, struct sk_buff *skb, int (*output)(struct sock *, struct sk_buff *)) @@ -897,21 +938,23 @@ static int br_nf_ip_fragment(struct sock *sk, struct sk_buff *skb, static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb) { - int ret; struct nf_bridge_info *nf_bridge; unsigned int mtu_reserved; - if (skb_is_gso(skb) || skb->protocol != htons(ETH_P_IP)) { + mtu_reserved = nf_bridge_mtu_reduction(skb); + + if (skb_is_gso(skb) || skb->len + mtu_reserved <= skb->dev->mtu) { nf_bridge_info_free(skb); return br_dev_queue_push_xmit(sk, skb); } - mtu_reserved = nf_bridge_mtu_reduction(skb); nf_bridge = nf_bridge_info_get(skb); + +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV4) /* This is wrong! We should preserve the original fragment * boundaries by preserving frag_list rather than refragmenting. */ - if (skb->len + mtu_reserved > skb->dev->mtu) { + if (skb->protocol == htons(ETH_P_IP)) { struct brnf_frag_data *data; if (br_validate_ipv4(skb)) @@ -928,21 +971,37 @@ static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb) skb_copy_from_linear_data_offset(skb, -data->size, data->mac, data->size); - ret = br_nf_ip_fragment(sk, skb, br_nf_push_frag_xmit); - } else { - nf_bridge_info_free(skb); - ret = br_dev_queue_push_xmit(sk, skb); + return br_nf_ip_fragment(sk, skb, br_nf_push_frag_xmit); } +#endif +#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) + if (skb->protocol == htons(ETH_P_IPV6)) { + const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops(); + struct brnf_frag_data *data; - return ret; -} -#else -static int br_nf_dev_queue_xmit(struct sock *sk, struct sk_buff *skb) -{ + if (br_validate_ipv6(skb)) + return NF_DROP; + + IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size; + + nf_bridge_update_protocol(skb); + + data = this_cpu_ptr(&brnf_frag_data_storage); + data->encap_size = nf_bridge_encap_header_len(skb); + data->size = ETH_HLEN + data->encap_size; + + skb_copy_from_linear_data_offset(skb, -data->size, data->mac, + data->size); + + if (v6ops) + return v6ops->fragment(sk, skb, br_nf_push_frag_xmit); + else + return -EMSGSIZE; + } +#endif nf_bridge_info_free(skb); return br_dev_queue_push_xmit(sk, skb); } -#endif /* PF_BRIDGE/POST_ROUTING ********************************************/ static unsigned int br_nf_post_routing(const struct nf_hook_ops *ops, diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 8cde96e68fd5..5dccced71269 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -18,6 +18,7 @@ #include #include #include +#include #include #define BR_HASH_BITS 8 @@ -214,7 +215,10 @@ struct net_bridge spinlock_t hash_lock; struct hlist_head hash[BR_HASH_SIZE]; #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - struct rtable fake_rtable; + union { + struct rtable fake_rtable; + struct rt6_info fake_rt6_info; + }; bool nf_call_iptables; bool nf_call_ip6tables; bool nf_call_arptables; diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index bbca09fe9553..b4de08a83e0b 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -191,7 +191,8 @@ static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, static const struct nf_ipv6_ops ipv6ops = { .chk_addr = ipv6_chk_addr, - .route_input = ip6_route_input + .route_input = ip6_route_input, + .fragment = ip6_fragment }; static const struct nf_afinfo nf_ip6_afinfo = {