diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c index 51c64b3d4e50..3fdb10d9bf7f 100644 --- a/net/netfilter/nf_flow_table_ip.c +++ b/net/netfilter/nf_flow_table_ip.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -637,6 +638,97 @@ static int nf_flow_tunnel_v4_push(struct net *net, struct sk_buff *skb, return 0; } +struct ipv6_tel_txoption { + struct ipv6_txoptions ops; + __u8 dst_opt[8]; +}; + +static int nf_flow_tunnel_ip6ip6_push(struct net *net, struct sk_buff *skb, + struct flow_offload_tuple *tuple, + struct in6_addr **ip6_daddr, + int encap_limit) +{ + struct ipv6hdr *ip6h = (struct ipv6hdr *)skb_network_header(skb); + u8 hop_limit = ip6h->hop_limit, proto = IPPROTO_IPV6; + struct rtable *rt = dst_rtable(tuple->dst_cache); + __u8 dsfield = ipv6_get_dsfield(ip6h); + struct flowi6 fl6 = { + .daddr = tuple->tun.src_v6, + .saddr = tuple->tun.dst_v6, + .flowi6_proto = proto, + }; + int err, mtu; + u32 headroom; + + err = iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6); + if (err) + return err; + + skb_set_inner_ipproto(skb, proto); + headroom = sizeof(*ip6h) + LL_RESERVED_SPACE(rt->dst.dev) + + rt->dst.header_len; + if (encap_limit) + headroom += 8; + err = skb_cow_head(skb, headroom); + if (err) + return err; + + skb_scrub_packet(skb, true); + mtu = dst_mtu(&rt->dst) - sizeof(*ip6h); + if (encap_limit) + mtu -= 8; + mtu = max(mtu, IPV6_MIN_MTU); + skb_dst_update_pmtu_no_confirm(skb, mtu); + + if (encap_limit > 0) { + struct ipv6_tel_txoption opt = { + .dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT, + .dst_opt[3] = 1, + .dst_opt[4] = encap_limit, + .dst_opt[5] = IPV6_TLV_PADN, + .dst_opt[6] = 1, + }; + struct ipv6_opt_hdr *hopt; + + opt.ops.dst1opt = (struct ipv6_opt_hdr *)opt.dst_opt; + opt.ops.opt_nflen = 8; + + hopt = skb_push(skb, ipv6_optlen(opt.ops.dst1opt)); + memcpy(hopt, opt.ops.dst1opt, ipv6_optlen(opt.ops.dst1opt)); + hopt->nexthdr = IPPROTO_IPV6; + proto = NEXTHDR_DEST; + } + + skb_push(skb, sizeof(*ip6h)); + skb_reset_network_header(skb); + + ip6h = ipv6_hdr(skb); + ip6_flow_hdr(ip6h, dsfield, + ip6_make_flowlabel(net, skb, fl6.flowlabel, true, &fl6)); + ip6h->hop_limit = hop_limit; + ip6h->nexthdr = proto; + ip6h->daddr = tuple->tun.src_v6; + ip6h->saddr = tuple->tun.dst_v6; + ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(*ip6h)); + IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); + + *ip6_daddr = &tuple->tun.src_v6; + + return 0; +} + +static int nf_flow_tunnel_v6_push(struct net *net, struct sk_buff *skb, + struct flow_offload_tuple *tuple, + struct in6_addr **ip6_daddr, + int encap_limit) +{ + if (tuple->tun_num) + return nf_flow_tunnel_ip6ip6_push(net, skb, tuple, ip6_daddr, + encap_limit); + + return 0; +} + static int nf_flow_encap_push(struct sk_buff *skb, struct flow_offload_tuple *tuple) { @@ -914,7 +1006,7 @@ static int nf_flow_tuple_ipv6(struct nf_flowtable_ctx *ctx, struct sk_buff *skb, static int nf_flow_offload_ipv6_forward(struct nf_flowtable_ctx *ctx, struct nf_flowtable *flow_table, struct flow_offload_tuple_rhash *tuplehash, - struct sk_buff *skb) + struct sk_buff *skb, int encap_limit) { enum flow_offload_tuple_dir dir; struct flow_offload *flow; @@ -925,6 +1017,12 @@ static int nf_flow_offload_ipv6_forward(struct nf_flowtable_ctx *ctx, flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); mtu = flow->tuplehash[dir].tuple.mtu + ctx->offset; + if (flow->tuplehash[!dir].tuple.tun_num) { + mtu -= sizeof(*ip6h); + if (encap_limit > 0) + mtu -= 8; /* encap limit option */ + } + if (unlikely(nf_flow_exceeds_mtu(skb, mtu))) return 0; @@ -977,6 +1075,7 @@ unsigned int nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) { + int encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT; struct flow_offload_tuple_rhash *tuplehash; struct nf_flowtable *flow_table = priv; struct flow_offload_tuple *other_tuple; @@ -995,7 +1094,8 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb, if (tuplehash == NULL) return NF_ACCEPT; - ret = nf_flow_offload_ipv6_forward(&ctx, flow_table, tuplehash, skb); + ret = nf_flow_offload_ipv6_forward(&ctx, flow_table, tuplehash, skb, + encap_limit); if (ret < 0) return NF_DROP; else if (ret == 0) @@ -1014,6 +1114,10 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb, other_tuple = &flow->tuplehash[!dir].tuple; ip6_daddr = &other_tuple->src_v6; + if (nf_flow_tunnel_v6_push(state->net, skb, other_tuple, + &ip6_daddr, encap_limit) < 0) + return NF_DROP; + if (nf_flow_encap_push(skb, other_tuple) < 0) return NF_DROP;