From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Add context structure and helper functions to look up for a matching
IPv6 entry in the flowtable and to forward packets.
No functional changes are intended.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
net/netfilter/nf_flow_table_ip.c | 112 ++++++++++++++++++++-----------
1 file changed, 71 insertions(+), 41 deletions(-)
diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 3fb476167d1d..d248763917ad 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -570,32 +570,31 @@ static void nf_flow_nat_ipv6(const struct flow_offload *flow,
}
}
-static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
- struct flow_offload_tuple *tuple, u32 *hdrsize,
- u32 offset)
+static int nf_flow_tuple_ipv6(struct nf_flowtable_ctx *ctx, struct sk_buff *skb,
+ struct flow_offload_tuple *tuple)
{
struct flow_ports *ports;
struct ipv6hdr *ip6h;
unsigned int thoff;
u8 nexthdr;
- thoff = sizeof(*ip6h) + offset;
+ thoff = sizeof(*ip6h) + ctx->offset;
if (!pskb_may_pull(skb, thoff))
return -1;
- ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
+ ip6h = (struct ipv6hdr *)(skb_network_header(skb) + ctx->offset);
nexthdr = ip6h->nexthdr;
switch (nexthdr) {
case IPPROTO_TCP:
- *hdrsize = sizeof(struct tcphdr);
+ ctx->hdrsize = sizeof(struct tcphdr);
break;
case IPPROTO_UDP:
- *hdrsize = sizeof(struct udphdr);
+ ctx->hdrsize = sizeof(struct udphdr);
break;
#ifdef CONFIG_NF_CT_PROTO_GRE
case IPPROTO_GRE:
- *hdrsize = sizeof(struct gre_base_hdr);
+ ctx->hdrsize = sizeof(struct gre_base_hdr);
break;
#endif
default:
@@ -605,7 +604,7 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
if (ip6h->hop_limit <= 1)
return -1;
- if (!pskb_may_pull(skb, thoff + *hdrsize))
+ if (!pskb_may_pull(skb, thoff + ctx->hdrsize))
return -1;
switch (nexthdr) {
@@ -625,65 +624,47 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
}
}
- ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
+ ip6h = (struct ipv6hdr *)(skb_network_header(skb) + ctx->offset);
tuple->src_v6 = ip6h->saddr;
tuple->dst_v6 = ip6h->daddr;
tuple->l3proto = AF_INET6;
tuple->l4proto = nexthdr;
- tuple->iifidx = dev->ifindex;
+ tuple->iifidx = ctx->in->ifindex;
nf_flow_tuple_encap(skb, tuple);
return 0;
}
-unsigned int
-nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
+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 flow_offload_tuple_rhash *tuplehash;
- struct nf_flowtable *flow_table = priv;
- struct flow_offload_tuple tuple = {};
enum flow_offload_tuple_dir dir;
- const struct in6_addr *nexthop;
struct flow_offload *flow;
- struct net_device *outdev;
unsigned int thoff, mtu;
- u32 hdrsize, offset = 0;
struct ipv6hdr *ip6h;
- struct rt6_info *rt;
- int ret;
-
- if (skb->protocol != htons(ETH_P_IPV6) &&
- !nf_flow_skb_encap_protocol(skb, htons(ETH_P_IPV6), &offset))
- return NF_ACCEPT;
-
- if (nf_flow_tuple_ipv6(skb, state->in, &tuple, &hdrsize, offset) < 0)
- return NF_ACCEPT;
-
- tuplehash = flow_offload_lookup(flow_table, &tuple);
- if (tuplehash == NULL)
- return NF_ACCEPT;
dir = tuplehash->tuple.dir;
flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
- mtu = flow->tuplehash[dir].tuple.mtu + offset;
+ mtu = flow->tuplehash[dir].tuple.mtu + ctx->offset;
if (unlikely(nf_flow_exceeds_mtu(skb, mtu)))
- return NF_ACCEPT;
+ return 0;
- ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
- thoff = sizeof(*ip6h) + offset;
+ ip6h = (struct ipv6hdr *)(skb_network_header(skb) + ctx->offset);
+ thoff = sizeof(*ip6h) + ctx->offset;
if (nf_flow_state_check(flow, ip6h->nexthdr, skb, thoff))
- return NF_ACCEPT;
+ return 0;
if (!nf_flow_dst_check(&tuplehash->tuple)) {
flow_offload_teardown(flow);
- return NF_ACCEPT;
+ return 0;
}
- if (skb_try_make_writable(skb, thoff + hdrsize))
- return NF_DROP;
+ if (skb_try_make_writable(skb, thoff + ctx->hdrsize))
+ return -1;
flow_offload_refresh(flow_table, flow);
@@ -698,6 +679,52 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
if (flow_table->flags & NF_FLOWTABLE_COUNTER)
nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
+ return 1;
+}
+
+static struct flow_offload_tuple_rhash *
+nf_flow_offload_ipv6_lookup(struct nf_flowtable_ctx *ctx,
+ struct nf_flowtable *flow_table,
+ struct sk_buff *skb)
+{
+ struct flow_offload_tuple tuple = {};
+
+ if (skb->protocol != htons(ETH_P_IPV6) &&
+ !nf_flow_skb_encap_protocol(skb, htons(ETH_P_IPV6), &ctx->offset))
+ return NULL;
+
+ if (nf_flow_tuple_ipv6(ctx, skb, &tuple) < 0)
+ return NULL;
+
+ return flow_offload_lookup(flow_table, &tuple);
+}
+
+unsigned int
+nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
+ const struct nf_hook_state *state)
+{
+ struct flow_offload_tuple_rhash *tuplehash;
+ struct nf_flowtable *flow_table = priv;
+ enum flow_offload_tuple_dir dir;
+ struct nf_flowtable_ctx ctx = {
+ .in = state->in,
+ };
+ const struct in6_addr *nexthop;
+ struct flow_offload *flow;
+ struct net_device *outdev;
+ struct rt6_info *rt;
+ int ret;
+
+ tuplehash = nf_flow_offload_ipv6_lookup(&ctx, flow_table, skb);
+ if (tuplehash == NULL)
+ return NF_ACCEPT;
+
+ ret = nf_flow_offload_ipv6_forward(&ctx, flow_table, tuplehash, skb);
+ if (ret < 0)
+ return NF_DROP;
+ else if (ret == 0)
+ return NF_ACCEPT;
+
if (unlikely(tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)) {
rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
@@ -706,6 +733,9 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
return nf_flow_xmit_xfrm(skb, state, &rt->dst);
}
+ dir = tuplehash->tuple.dir;
+ flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
+
switch (tuplehash->tuple.xmit_type) {
case FLOW_OFFLOAD_XMIT_NEIGH:
rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
--
2.40.1
