netfilter: flowtable: add vlan support

Add the vlan id and protocol to the flow tuple to uniquely identify
flows from the receive path. For the transmit path, dev_hard_header() on
the vlan device push the headers. This patch includes support for two
vlan headers (QinQ) from the ingress path.

Add a generic encap field to the flowtable entry which stores the
protocol and the tag id. This allows to reuse these fields in the PPPoE
support coming in a later patch.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h
index 41c8436..e34fd3e 100644 (file)
--- a/include/net/netfilter/nf_flow_table.h
+++ b/include/net/netfilter/nf_flow_table.h
@@ -95,6 +95,8 @@ enum flow_offload_xmit_type {
        FLOW_OFFLOAD_XMIT_DIRECT,
 };
 
+#define NF_FLOW_TABLE_ENCAP_MAX                2
+
 struct flow_offload_tuple {
        union {
                struct in_addr          src_v4;
@@ -113,13 +115,17 @@ struct flow_offload_tuple {
 
        u8                              l3proto;
        u8                              l4proto;
+       struct {
+               u16                     id;
+               __be16                  proto;
+       } encap[NF_FLOW_TABLE_ENCAP_MAX];
 
        /* All members above are keys for lookups, see flow_offload_hash(). */
        struct { }                      __hash;
 
-       u8                              dir:6,
-                                       xmit_type:2;
-
+       u8                              dir:4,
+                                       xmit_type:2,
+                                       encap_num:2;
        u16                             mtu;
        union {
                struct dst_entry        *dst_cache;
@@ -174,6 +180,11 @@ struct nf_flow_route {
                struct dst_entry                *dst;
                struct {
                        u32                     ifindex;
+                       struct {
+                               u16             id;
+                               __be16          proto;
+                       } encap[NF_FLOW_TABLE_ENCAP_MAX];
+                       u8                      num_encaps;
                } in;
                struct {
                        u32                     ifindex;

diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index a92acb3..595f443 100644 (file)
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -80,6 +80,7 @@ static int flow_offload_fill_route(struct flow_offload *flow,
 {
        struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
        struct dst_entry *dst = route->tuple[dir].dst;
+       int i, j = 0;
 
        switch (flow_tuple->l3proto) {
        case NFPROTO_IPV4:
@@ -91,6 +92,12 @@ static int flow_offload_fill_route(struct flow_offload *flow,
        }
 
        flow_tuple->iifidx = route->tuple[dir].in.ifindex;
+       for (i = route->tuple[dir].in.num_encaps - 1; i >= 0; i--) {
+               flow_tuple->encap[j].id = route->tuple[dir].in.encap[i].id;
+               flow_tuple->encap[j].proto = route->tuple[dir].in.encap[i].proto;
+               j++;
+       }
+       flow_tuple->encap_num = route->tuple[dir].in.num_encaps;
 
        switch (route->tuple[dir].xmit_type) {
        case FLOW_OFFLOAD_XMIT_DIRECT:

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 9e84767..d906362 100644 (file)
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -136,23 +136,44 @@ static bool ip_has_options(unsigned int thoff)
        return thoff != sizeof(struct iphdr);
 }
 
+static void nf_flow_tuple_encap(struct sk_buff *skb,
+                               struct flow_offload_tuple *tuple)
+{
+       int i = 0;
+
+       if (skb_vlan_tag_present(skb)) {
+               tuple->encap[i].id = skb_vlan_tag_get(skb);
+               tuple->encap[i].proto = skb->vlan_proto;
+               i++;
+       }
+       if (skb->protocol == htons(ETH_P_8021Q)) {
+               struct vlan_ethhdr *veth = (struct vlan_ethhdr *)skb_mac_header(skb);
+
+               tuple->encap[i].id = ntohs(veth->h_vlan_TCI);
+               tuple->encap[i].proto = skb->protocol;
+       }
+}
+
 static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
-                           struct flow_offload_tuple *tuple, u32 *hdrsize)
+                           struct flow_offload_tuple *tuple, u32 *hdrsize,
+                           u32 offset)
 {
        struct flow_ports *ports;
        unsigned int thoff;
        struct iphdr *iph;
 
-       if (!pskb_may_pull(skb, sizeof(*iph)))
+       if (!pskb_may_pull(skb, sizeof(*iph) + offset))
                return -1;
 
-       iph = ip_hdr(skb);
-       thoff = iph->ihl * 4;
+       iph = (struct iphdr *)(skb_network_header(skb) + offset);
+       thoff = (iph->ihl * 4);
 
        if (ip_is_fragment(iph) ||
            unlikely(ip_has_options(thoff)))
                return -1;
 
+       thoff += offset;
+
        switch (iph->protocol) {
        case IPPROTO_TCP:
                *hdrsize = sizeof(struct tcphdr);
@@ -167,11 +188,10 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
        if (iph->ttl <= 1)
                return -1;
 
-       thoff = iph->ihl * 4;
        if (!pskb_may_pull(skb, thoff + *hdrsize))
                return -1;
 
-       iph = ip_hdr(skb);
+       iph = (struct iphdr *)(skb_network_header(skb) + offset);
        ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 
        tuple->src_v4.s_addr    = iph->saddr;
@@ -181,6 +201,7 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
        tuple->l3proto          = AF_INET;
        tuple->l4proto          = iph->protocol;
        tuple->iifidx           = dev->ifindex;
+       nf_flow_tuple_encap(skb, tuple);
 
        return 0;
 }
@@ -207,6 +228,43 @@ static unsigned int nf_flow_xmit_xfrm(struct sk_buff *skb,
        return NF_STOLEN;
 }
 
+static bool nf_flow_skb_encap_protocol(const struct sk_buff *skb, __be16 proto,
+                                      u32 *offset)
+{
+       if (skb->protocol == htons(ETH_P_8021Q)) {
+               struct vlan_ethhdr *veth;
+
+               veth = (struct vlan_ethhdr *)skb_mac_header(skb);
+               if (veth->h_vlan_encapsulated_proto == proto) {
+                       *offset += VLAN_HLEN;
+                       return true;
+               }
+       }
+
+       return false;
+}
+
+static void nf_flow_encap_pop(struct sk_buff *skb,
+                             struct flow_offload_tuple_rhash *tuplehash)
+{
+       struct vlan_hdr *vlan_hdr;
+       int i;
+
+       for (i = 0; i < tuplehash->tuple.encap_num; i++) {
+               if (skb_vlan_tag_present(skb)) {
+                       __vlan_hwaccel_clear_tag(skb);
+                       continue;
+               }
+               if (skb->protocol == htons(ETH_P_8021Q)) {
+                       vlan_hdr = (struct vlan_hdr *)skb->data;
+                       __skb_pull(skb, VLAN_HLEN);
+                       vlan_set_encap_proto(skb, vlan_hdr);
+                       skb_reset_network_header(skb);
+                       break;
+               }
+       }
+}
+
 static unsigned int nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,
                                       const struct flow_offload_tuple_rhash *tuplehash,
                                       unsigned short type)
@@ -235,17 +293,18 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
        enum flow_offload_tuple_dir dir;
        struct flow_offload *flow;
        struct net_device *outdev;
+       u32 hdrsize, offset = 0;
+       unsigned int thoff, mtu;
        struct rtable *rt;
-       unsigned int thoff;
        struct iphdr *iph;
        __be32 nexthop;
-       u32 hdrsize;
        int ret;
 
-       if (skb->protocol != htons(ETH_P_IP))
+       if (skb->protocol != htons(ETH_P_IP) &&
+           !nf_flow_skb_encap_protocol(skb, htons(ETH_P_IP), &offset))
                return NF_ACCEPT;
 
-       if (nf_flow_tuple_ip(skb, state->in, &tuple, &hdrsize) < 0)
+       if (nf_flow_tuple_ip(skb, state->in, &tuple, &hdrsize, offset) < 0)
                return NF_ACCEPT;
 
        tuplehash = flow_offload_lookup(flow_table, &tuple);
@@ -255,11 +314,12 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
        dir = tuplehash->tuple.dir;
        flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
 
-       if (unlikely(nf_flow_exceeds_mtu(skb, flow->tuplehash[dir].tuple.mtu)))
+       mtu = flow->tuplehash[dir].tuple.mtu + offset;
+       if (unlikely(nf_flow_exceeds_mtu(skb, mtu)))
                return NF_ACCEPT;
 
-       iph = ip_hdr(skb);
-       thoff = iph->ihl * 4;
+       iph = (struct iphdr *)(skb_network_header(skb) + offset);
+       thoff = (iph->ihl * 4) + offset;
        if (nf_flow_state_check(flow, iph->protocol, skb, thoff))
                return NF_ACCEPT;
 
@@ -277,6 +337,9 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
 
        flow_offload_refresh(flow_table, flow);
 
+       nf_flow_encap_pop(skb, tuplehash);
+       thoff -= offset;
+
        iph = ip_hdr(skb);
        nf_flow_nat_ip(flow, skb, thoff, dir, iph);
 
@@ -418,16 +481,18 @@ 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)
+                             struct flow_offload_tuple *tuple, u32 *hdrsize,
+                             u32 offset)
 {
        struct flow_ports *ports;
        struct ipv6hdr *ip6h;
        unsigned int thoff;
 
-       if (!pskb_may_pull(skb, sizeof(*ip6h)))
+       thoff = sizeof(*ip6h) + offset;
+       if (!pskb_may_pull(skb, thoff))
                return -1;
 
-       ip6h = ipv6_hdr(skb);
+       ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
 
        switch (ip6h->nexthdr) {
        case IPPROTO_TCP:
@@ -443,11 +508,10 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
        if (ip6h->hop_limit <= 1)
                return -1;
 
-       thoff = sizeof(*ip6h);
        if (!pskb_may_pull(skb, thoff + *hdrsize))
                return -1;
 
-       ip6h = ipv6_hdr(skb);
+       ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
        ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 
        tuple->src_v6           = ip6h->saddr;
@@ -457,6 +521,7 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
        tuple->l3proto          = AF_INET6;
        tuple->l4proto          = ip6h->nexthdr;
        tuple->iifidx           = dev->ifindex;
+       nf_flow_tuple_encap(skb, tuple);
 
        return 0;
 }
@@ -472,15 +537,17 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
        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;
-       u32 hdrsize;
        int ret;
 
-       if (skb->protocol != htons(ETH_P_IPV6))
+       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) < 0)
+       if (nf_flow_tuple_ipv6(skb, state->in, &tuple, &hdrsize, offset) < 0)
                return NF_ACCEPT;
 
        tuplehash = flow_offload_lookup(flow_table, &tuple);
@@ -490,11 +557,13 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
        dir = tuplehash->tuple.dir;
        flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
 
-       if (unlikely(nf_flow_exceeds_mtu(skb, flow->tuplehash[dir].tuple.mtu)))
+       mtu = flow->tuplehash[dir].tuple.mtu + offset;
+       if (unlikely(nf_flow_exceeds_mtu(skb, mtu)))
                return NF_ACCEPT;
 
-       if (nf_flow_state_check(flow, ipv6_hdr(skb)->nexthdr, skb,
-                               sizeof(*ip6h)))
+       ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
+       thoff = sizeof(*ip6h) + offset;
+       if (nf_flow_state_check(flow, ip6h->nexthdr, skb, thoff))
                return NF_ACCEPT;
 
        if (tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_NEIGH ||
@@ -506,11 +575,13 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
                }
        }
 
-       if (skb_try_make_writable(skb, sizeof(*ip6h) + hdrsize))
+       if (skb_try_make_writable(skb, thoff + hdrsize))
                return NF_DROP;
 
        flow_offload_refresh(flow_table, flow);
 
+       nf_flow_encap_pop(skb, tuplehash);
+
        ip6h = ipv6_hdr(skb);
        nf_flow_nat_ipv6(flow, skb, dir, ip6h);
 

diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index a6595dc..8392b1a 100644 (file)
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -66,6 +66,11 @@ static int nft_dev_fill_forward_path(const struct nf_flow_route *route,
 struct nft_forward_info {
        const struct net_device *indev;
        const struct net_device *outdev;
+       struct id {
+               __u16   id;
+               __be16  proto;
+       } encap[NF_FLOW_TABLE_ENCAP_MAX];
+       u8 num_encaps;
        u8 h_source[ETH_ALEN];
        u8 h_dest[ETH_ALEN];
        enum flow_offload_xmit_type xmit_type;
@@ -84,9 +89,23 @@ static void nft_dev_path_info(const struct net_device_path_stack *stack,
                path = &stack->path[i];
                switch (path->type) {
                case DEV_PATH_ETHERNET:
+               case DEV_PATH_VLAN:
                        info->indev = path->dev;
                        if (is_zero_ether_addr(info->h_source))
                                memcpy(info->h_source, path->dev->dev_addr, ETH_ALEN);
+
+                       if (path->type == DEV_PATH_ETHERNET)
+                               break;
+
+                       /* DEV_PATH_VLAN */
+                       if (info->num_encaps >= NF_FLOW_TABLE_ENCAP_MAX) {
+                               info->indev = NULL;
+                               break;
+                       }
+                       info->outdev = path->dev;
+                       info->encap[info->num_encaps].id = path->encap.id;
+                       info->encap[info->num_encaps].proto = path->encap.proto;
+                       info->num_encaps++;
                        break;
                case DEV_PATH_BRIDGE:
                        if (is_zero_ether_addr(info->h_source))
@@ -94,7 +113,6 @@ static void nft_dev_path_info(const struct net_device_path_stack *stack,
 
                        info->xmit_type = FLOW_OFFLOAD_XMIT_DIRECT;
                        break;
-               case DEV_PATH_VLAN:
                default:
                        info->indev = NULL;
                        break;
@@ -130,6 +148,7 @@ static void nft_dev_forward_path(struct nf_flow_route *route,
        struct net_device_path_stack stack;
        struct nft_forward_info info = {};
        unsigned char ha[ETH_ALEN];
+       int i;
 
        if (nft_dev_fill_forward_path(route, dst, ct, dir, ha, &stack) >= 0)
                nft_dev_path_info(&stack, &info, ha);
@@ -138,6 +157,11 @@ static void nft_dev_forward_path(struct nf_flow_route *route,
                return;
 
        route->tuple[!dir].in.ifindex = info.indev->ifindex;
+       for (i = 0; i < info.num_encaps; i++) {
+               route->tuple[!dir].in.encap[i].id = info.encap[i].id;
+               route->tuple[!dir].in.encap[i].proto = info.encap[i].proto;
+       }
+       route->tuple[!dir].in.num_encaps = info.num_encaps;
 
        if (info.xmit_type == FLOW_OFFLOAD_XMIT_DIRECT) {
                memcpy(route->tuple[dir].out.h_source, info.h_source, ETH_ALEN);