include/linux/netfilter_bridge.h

   1 #ifndef __LINUX_BRIDGE_NETFILTER_H
   2 #define __LINUX_BRIDGE_NETFILTER_H
   3
   4 #include <uapi/linux/netfilter_bridge.h>
   5
   6
   7 enum nf_br_hook_priorities {
   8         NF_BR_PRI_FIRST = INT_MIN,
   9         NF_BR_PRI_NAT_DST_BRIDGED = -300,
  10         NF_BR_PRI_FILTER_BRIDGED = -200,
  11         NF_BR_PRI_BRNF = 0,
  12         NF_BR_PRI_NAT_DST_OTHER = 100,
  13         NF_BR_PRI_FILTER_OTHER = 200,
  14         NF_BR_PRI_NAT_SRC = 300,
  15         NF_BR_PRI_LAST = INT_MAX,
  16 };
  17
  18 #ifdef CONFIG_BRIDGE_NETFILTER
  19
  20 #define BRNF_PKT_TYPE                   0x01
  21 #define BRNF_BRIDGED_DNAT               0x02
  22 #define BRNF_BRIDGED                    0x04
  23 #define BRNF_NF_BRIDGE_PREROUTING       0x08
  24 #define BRNF_8021Q                      0x10
  25 #define BRNF_PPPoE                      0x20
  26
  27 /* Only used in br_forward.c */
  28 int nf_bridge_copy_header(struct sk_buff *skb);
  29 static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
  30 {
  31         if (skb->nf_bridge &&
  32             skb->nf_bridge->mask & (BRNF_BRIDGED | BRNF_BRIDGED_DNAT))
  33                 return nf_bridge_copy_header(skb);
  34         return 0;
  35 }
  36
  37 static inline unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
  38 {
  39         switch (skb->protocol) {
  40         case __cpu_to_be16(ETH_P_8021Q):
  41                 return VLAN_HLEN;
  42         case __cpu_to_be16(ETH_P_PPP_SES):
  43                 return PPPOE_SES_HLEN;
  44         default:
  45                 return 0;
  46         }
  47 }
  48
  49 static inline unsigned int nf_bridge_mtu_reduction(const struct sk_buff *skb)
  50 {
  51         if (unlikely(skb->nf_bridge->mask & BRNF_PPPoE))
  52                 return PPPOE_SES_HLEN;
  53         return 0;
  54 }
  55
  56 int br_handle_frame_finish(struct sk_buff *skb);
  57 /* Only used in br_device.c */
  58 static inline int br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb)
  59 {
  60         struct nf_bridge_info *nf_bridge = skb->nf_bridge;
  61
  62         skb_pull(skb, ETH_HLEN);
  63         nf_bridge->mask ^= BRNF_BRIDGED_DNAT;
  64         skb_copy_to_linear_data_offset(skb, -(ETH_HLEN-ETH_ALEN),
  65                                        skb->nf_bridge->data, ETH_HLEN-ETH_ALEN);
  66         skb->dev = nf_bridge->physindev;
  67         return br_handle_frame_finish(skb);
  68 }
  69
  70 /* This is called by the IP fragmenting code and it ensures there is
  71  * enough room for the encapsulating header (if there is one). */
  72 static inline unsigned int nf_bridge_pad(const struct sk_buff *skb)
  73 {
  74         if (skb->nf_bridge)
  75                 return nf_bridge_encap_header_len(skb);
  76         return 0;
  77 }
  78
  79 struct bridge_skb_cb {
  80         union {
  81                 __be32 ipv4;
  82         } daddr;
  83 };
  84
  85 static inline void br_drop_fake_rtable(struct sk_buff *skb)
  86 {
  87         struct dst_entry *dst = skb_dst(skb);
  88
  89         if (dst && (dst->flags & DST_FAKE_RTABLE))
  90                 skb_dst_drop(skb);
  91 }
  92
  93 #else
  94 #define nf_bridge_maybe_copy_header(skb)        (0)
  95 #define nf_bridge_pad(skb)                      (0)
  96 #define br_drop_fake_rtable(skb)                do { } while (0)
  97 #endif /* CONFIG_BRIDGE_NETFILTER */
  98
  99 #endif