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Diffstat (limited to 'net/ipv4/netfilter/nf_flow_table_ipv4.c')
-rw-r--r--net/ipv4/netfilter/nf_flow_table_ipv4.c255
1 files changed, 1 insertions, 254 deletions
diff --git a/net/ipv4/netfilter/nf_flow_table_ipv4.c b/net/ipv4/netfilter/nf_flow_table_ipv4.c
index 0cd46bffa469..e1e56d7123d2 100644
--- a/net/ipv4/netfilter/nf_flow_table_ipv4.c
+++ b/net/ipv4/netfilter/nf_flow_table_ipv4.c
@@ -2,265 +2,12 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netfilter.h>
-#include <linux/rhashtable.h>
-#include <linux/ip.h>
-#include <linux/netdevice.h>
-#include <net/ip.h>
-#include <net/neighbour.h>
#include <net/netfilter/nf_flow_table.h>
#include <net/netfilter/nf_tables.h>
-/* For layer 4 checksum field offset. */
-#include <linux/tcp.h>
-#include <linux/udp.h>
-
-static int nf_flow_nat_ip_tcp(struct sk_buff *skb, unsigned int thoff,
- __be32 addr, __be32 new_addr)
-{
- struct tcphdr *tcph;
-
- if (!pskb_may_pull(skb, thoff + sizeof(*tcph)) ||
- skb_try_make_writable(skb, thoff + sizeof(*tcph)))
- return -1;
-
- tcph = (void *)(skb_network_header(skb) + thoff);
- inet_proto_csum_replace4(&tcph->check, skb, addr, new_addr, true);
-
- return 0;
-}
-
-static int nf_flow_nat_ip_udp(struct sk_buff *skb, unsigned int thoff,
- __be32 addr, __be32 new_addr)
-{
- struct udphdr *udph;
-
- if (!pskb_may_pull(skb, thoff + sizeof(*udph)) ||
- skb_try_make_writable(skb, thoff + sizeof(*udph)))
- return -1;
-
- udph = (void *)(skb_network_header(skb) + thoff);
- if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
- inet_proto_csum_replace4(&udph->check, skb, addr,
- new_addr, true);
- if (!udph->check)
- udph->check = CSUM_MANGLED_0;
- }
-
- return 0;
-}
-
-static int nf_flow_nat_ip_l4proto(struct sk_buff *skb, struct iphdr *iph,
- unsigned int thoff, __be32 addr,
- __be32 new_addr)
-{
- switch (iph->protocol) {
- case IPPROTO_TCP:
- if (nf_flow_nat_ip_tcp(skb, thoff, addr, new_addr) < 0)
- return NF_DROP;
- break;
- case IPPROTO_UDP:
- if (nf_flow_nat_ip_udp(skb, thoff, addr, new_addr) < 0)
- return NF_DROP;
- break;
- }
-
- return 0;
-}
-
-static int nf_flow_snat_ip(const struct flow_offload *flow, struct sk_buff *skb,
- struct iphdr *iph, unsigned int thoff,
- enum flow_offload_tuple_dir dir)
-{
- __be32 addr, new_addr;
-
- switch (dir) {
- case FLOW_OFFLOAD_DIR_ORIGINAL:
- addr = iph->saddr;
- new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v4.s_addr;
- iph->saddr = new_addr;
- break;
- case FLOW_OFFLOAD_DIR_REPLY:
- addr = iph->daddr;
- new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v4.s_addr;
- iph->daddr = new_addr;
- break;
- default:
- return -1;
- }
- csum_replace4(&iph->check, addr, new_addr);
-
- return nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
-}
-
-static int nf_flow_dnat_ip(const struct flow_offload *flow, struct sk_buff *skb,
- struct iphdr *iph, unsigned int thoff,
- enum flow_offload_tuple_dir dir)
-{
- __be32 addr, new_addr;
-
- switch (dir) {
- case FLOW_OFFLOAD_DIR_ORIGINAL:
- addr = iph->daddr;
- new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr;
- iph->daddr = new_addr;
- break;
- case FLOW_OFFLOAD_DIR_REPLY:
- addr = iph->saddr;
- new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr;
- iph->saddr = new_addr;
- break;
- default:
- return -1;
- }
- csum_replace4(&iph->check, addr, new_addr);
-
- return nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
-}
-
-static int nf_flow_nat_ip(const struct flow_offload *flow, struct sk_buff *skb,
- enum flow_offload_tuple_dir dir)
-{
- struct iphdr *iph = ip_hdr(skb);
- unsigned int thoff = iph->ihl * 4;
-
- if (flow->flags & FLOW_OFFLOAD_SNAT &&
- (nf_flow_snat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
- nf_flow_snat_ip(flow, skb, iph, thoff, dir) < 0))
- return -1;
- if (flow->flags & FLOW_OFFLOAD_DNAT &&
- (nf_flow_dnat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
- nf_flow_dnat_ip(flow, skb, iph, thoff, dir) < 0))
- return -1;
-
- return 0;
-}
-
-static bool ip_has_options(unsigned int thoff)
-{
- return thoff != sizeof(struct iphdr);
-}
-
-static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
- struct flow_offload_tuple *tuple)
-{
- struct flow_ports *ports;
- unsigned int thoff;
- struct iphdr *iph;
-
- if (!pskb_may_pull(skb, sizeof(*iph)))
- return -1;
-
- iph = ip_hdr(skb);
- thoff = iph->ihl * 4;
-
- if (ip_is_fragment(iph) ||
- unlikely(ip_has_options(thoff)))
- return -1;
-
- if (iph->protocol != IPPROTO_TCP &&
- iph->protocol != IPPROTO_UDP)
- return -1;
-
- thoff = iph->ihl * 4;
- if (!pskb_may_pull(skb, thoff + sizeof(*ports)))
- return -1;
-
- ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
-
- tuple->src_v4.s_addr = iph->saddr;
- tuple->dst_v4.s_addr = iph->daddr;
- tuple->src_port = ports->source;
- tuple->dst_port = ports->dest;
- tuple->l3proto = AF_INET;
- tuple->l4proto = iph->protocol;
- tuple->iifidx = dev->ifindex;
-
- return 0;
-}
-
-/* Based on ip_exceeds_mtu(). */
-static bool __nf_flow_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
-{
- if (skb->len <= mtu)
- return false;
-
- if ((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0)
- return false;
-
- if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))
- return false;
-
- return true;
-}
-
-static bool nf_flow_exceeds_mtu(struct sk_buff *skb, const struct rtable *rt)
-{
- u32 mtu;
-
- mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
- if (__nf_flow_exceeds_mtu(skb, mtu))
- return true;
-
- return false;
-}
-
-unsigned int
-nf_flow_offload_ip_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;
- struct flow_offload_tuple tuple = {};
- enum flow_offload_tuple_dir dir;
- struct flow_offload *flow;
- struct net_device *outdev;
- const struct rtable *rt;
- struct iphdr *iph;
- __be32 nexthop;
-
- if (skb->protocol != htons(ETH_P_IP))
- return NF_ACCEPT;
-
- if (nf_flow_tuple_ip(skb, state->in, &tuple) < 0)
- return NF_ACCEPT;
-
- tuplehash = flow_offload_lookup(flow_table, &tuple);
- if (tuplehash == NULL)
- return NF_ACCEPT;
-
- outdev = dev_get_by_index_rcu(state->net, tuplehash->tuple.oifidx);
- if (!outdev)
- return NF_ACCEPT;
-
- dir = tuplehash->tuple.dir;
- flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
-
- rt = (const struct rtable *)flow->tuplehash[dir].tuple.dst_cache;
- if (unlikely(nf_flow_exceeds_mtu(skb, rt)))
- return NF_ACCEPT;
-
- if (skb_try_make_writable(skb, sizeof(*iph)))
- return NF_DROP;
-
- if (flow->flags & (FLOW_OFFLOAD_SNAT | FLOW_OFFLOAD_DNAT) &&
- nf_flow_nat_ip(flow, skb, dir) < 0)
- return NF_DROP;
-
- flow->timeout = (u32)jiffies + NF_FLOW_TIMEOUT;
- iph = ip_hdr(skb);
- ip_decrease_ttl(iph);
-
- skb->dev = outdev;
- nexthop = rt_nexthop(rt, flow->tuplehash[!dir].tuple.src_v4.s_addr);
- neigh_xmit(NEIGH_ARP_TABLE, outdev, &nexthop, skb);
-
- return NF_STOLEN;
-}
-EXPORT_SYMBOL_GPL(nf_flow_offload_ip_hook);
static struct nf_flowtable_type flowtable_ipv4 = {
.family = NFPROTO_IPV4,
- .params = &nf_flow_offload_rhash_params,
- .gc = nf_flow_offload_work_gc,
+ .init = nf_flow_table_init,
.free = nf_flow_table_free,
.hook = nf_flow_offload_ip_hook,
.owner = THIS_MODULE,