Add Nicira extension to OpenFlow for dropping spoofed ARP packets.

[sliver-openvswitch.git] / datapath / flow.c

diff --git a/datapath/flow.c b/datapath/flow.c
index f769b14..c37c8e0 100644 (file)
--- a/datapath/flow.c
+++ b/datapath/flow.c
@@ -34,28 +34,13 @@
 struct kmem_cache *flow_cache;
 static unsigned int hash_seed;
 
-struct arp_eth_header
-{
-       __be16      ar_hrd;     /* format of hardware address   */
-       __be16      ar_pro;     /* format of protocol address   */
-       unsigned char   ar_hln; /* length of hardware address   */
-       unsigned char   ar_pln; /* length of protocol address   */
-       __be16      ar_op;      /* ARP opcode (command)     */
-
-       /* Ethernet+IPv4 specific members. */
-       unsigned char       ar_sha[ETH_ALEN];   /* sender hardware address  */
-       unsigned char       ar_sip[4];          /* sender IP address        */
-       unsigned char       ar_tha[ETH_ALEN];   /* target hardware address  */
-       unsigned char       ar_tip[4];          /* target IP address        */
-} __attribute__((packed));
-
-static inline int arphdr_ok(struct sk_buff *skb)
+static inline bool arphdr_ok(struct sk_buff *skb)
 {
        int nh_ofs = skb_network_offset(skb);
        return pskb_may_pull(skb, nh_ofs + sizeof(struct arp_eth_header));
 }
 
-static inline int iphdr_ok(struct sk_buff *skb)
+static inline bool iphdr_ok(struct sk_buff *skb)
 {
        int nh_ofs = skb_network_offset(skb);
        if (skb->len >= nh_ofs + sizeof(struct iphdr)) {
@@ -63,10 +48,10 @@ static inline int iphdr_ok(struct sk_buff *skb)
                return (ip_len >= sizeof(struct iphdr)
                        && pskb_may_pull(skb, nh_ofs + ip_len));
        }
-       return 0;
+       return false;
 }
 
-static inline int tcphdr_ok(struct sk_buff *skb)
+static inline bool tcphdr_ok(struct sk_buff *skb)
 {
        int th_ofs = skb_transport_offset(skb);
        if (pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))) {
@@ -74,16 +59,16 @@ static inline int tcphdr_ok(struct sk_buff *skb)
                return (tcp_len >= sizeof(struct tcphdr)
                        && skb->len >= th_ofs + tcp_len);
        }
-       return 0;
+       return false;
 }
 
-static inline int udphdr_ok(struct sk_buff *skb)
+static inline bool udphdr_ok(struct sk_buff *skb)
 {
        int th_ofs = skb_transport_offset(skb);
        return pskb_may_pull(skb, th_ofs + sizeof(struct udphdr));
 }
 
-static inline int icmphdr_ok(struct sk_buff *skb)
+static inline bool icmphdr_ok(struct sk_buff *skb)
 {
        int th_ofs = skb_transport_offset(skb);
        return pskb_may_pull(skb, th_ofs + sizeof(struct icmphdr));
@@ -219,22 +204,29 @@ static __be16 parse_ethertype(struct sk_buff *skb)
        return llc->ethertype;
 }
 
-/* Parses the Ethernet frame in 'skb', which was received on 'in_port',
- * and initializes 'key' to match.  Returns 1 if 'skb' contains an IP
- * fragment, 0 otherwise. */
+/**
+ * flow_extract - extracts a flow key from an Ethernet frame.
+ * @skb: sk_buff that contains the frame, with skb->data pointing to the
+ * Ethernet header
+ * @in_port: port number on which @skb was received.
+ * @key: output flow key
+ *
+ * The caller must ensure that skb->len >= ETH_HLEN.
+ *
+ * Sets OVS_CB(skb)->is_frag to %true if @skb is an IPv4 fragment, otherwise to
+ * %false.
+ */
 int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
 {
        struct ethhdr *eth;
-       int retval = 0;
 
        memset(key, 0, sizeof *key);
        key->tun_id = OVS_CB(skb)->tun_id;
        key->in_port = in_port;
        key->dl_vlan = htons(ODP_VLAN_NONE);
+       OVS_CB(skb)->is_frag = false;
 
-       if (skb->len < sizeof *eth)
-               return 0;
-       if (!pskb_may_pull(skb, skb->len >= 64 ? 64 : skb->len))
+       if (!pskb_may_pull(skb, min(skb->len, 64u)))
                return 0;
 
        skb_reset_mac_header(skb);
@@ -302,7 +294,7 @@ int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
                                }
                        }
                } else {
-                       retval = 1;
+                       OVS_CB(skb)->is_frag = true;
                }
        } else if (key->dl_type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
                struct arp_eth_header *arp;
@@ -328,7 +320,7 @@ int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
        } else {
                skb_reset_transport_header(skb);
        }
-       return retval;
+       return 0;
 }
 
 u32 flow_hash(const struct odp_flow_key *key)