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#ifndef __LINUX_BRIDGE_NETFILTER_H
#define __LINUX_BRIDGE_NETFILTER_H
#include <uapi/linux/netfilter_bridge.h>
enum nf_br_hook_priorities {
NF_BR_PRI_FIRST = INT_MIN,
NF_BR_PRI_NAT_DST_BRIDGED = -300,
NF_BR_PRI_FILTER_BRIDGED = -200,
NF_BR_PRI_BRNF = 0,
NF_BR_PRI_NAT_DST_OTHER = 100,
NF_BR_PRI_FILTER_OTHER = 200,
NF_BR_PRI_NAT_SRC = 300,
NF_BR_PRI_LAST = INT_MAX,
};
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
#define BRNF_PKT_TYPE 0x01
#define BRNF_BRIDGED_DNAT 0x02
#define BRNF_BRIDGED 0x04
#define BRNF_NF_BRIDGE_PREROUTING 0x08
#define BRNF_8021Q 0x10
#define BRNF_PPPoE 0x20
static inline unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
{
switch (skb->protocol) {
case __cpu_to_be16(ETH_P_8021Q):
return VLAN_HLEN;
case __cpu_to_be16(ETH_P_PPP_SES):
return PPPOE_SES_HLEN;
default:
return 0;
}
}
static inline void nf_bridge_update_protocol(struct sk_buff *skb)
{
if (skb->nf_bridge->mask & BRNF_8021Q)
skb->protocol = htons(ETH_P_8021Q);
else if (skb->nf_bridge->mask & BRNF_PPPoE)
skb->protocol = htons(ETH_P_PPP_SES);
}
/* Fill in the header for fragmented IP packets handled by
* the IPv4 connection tracking code.
*
* Only used in br_forward.c
*/
static inline int nf_bridge_copy_header(struct sk_buff *skb)
{
int err;
unsigned int header_size;
nf_bridge_update_protocol(skb);
header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);
err = skb_cow_head(skb, header_size);
if (err)
return err;
skb_copy_to_linear_data_offset(skb, -header_size,
skb->nf_bridge->data, header_size);
__skb_push(skb, nf_bridge_encap_header_len(skb));
return 0;
}
static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
{
if (skb->nf_bridge &&
skb->nf_bridge->mask & (BRNF_BRIDGED | BRNF_BRIDGED_DNAT))
return nf_bridge_copy_header(skb);
return 0;
}
static inline unsigned int nf_bridge_mtu_reduction(const struct sk_buff *skb)
{
if (unlikely(skb->nf_bridge->mask & BRNF_PPPoE))
return PPPOE_SES_HLEN;
return 0;
}
int br_handle_frame_finish(struct sk_buff *skb);
/* Only used in br_device.c */
static inline int br_nf_pre_routing_finish_bridge_slow(struct sk_buff *skb)
{
struct nf_bridge_info *nf_bridge = skb->nf_bridge;
skb_pull(skb, ETH_HLEN);
nf_bridge->mask ^= BRNF_BRIDGED_DNAT;
skb_copy_to_linear_data_offset(skb, -(ETH_HLEN-ETH_ALEN),
skb->nf_bridge->data, ETH_HLEN-ETH_ALEN);
skb->dev = nf_bridge->physindev;
return br_handle_frame_finish(skb);
}
/* This is called by the IP fragmenting code and it ensures there is
* enough room for the encapsulating header (if there is one). */
static inline unsigned int nf_bridge_pad(const struct sk_buff *skb)
{
if (skb->nf_bridge)
return nf_bridge_encap_header_len(skb);
return 0;
}
struct bridge_skb_cb {
union {
__be32 ipv4;
} daddr;
};
static inline void br_drop_fake_rtable(struct sk_buff *skb)
{
struct dst_entry *dst = skb_dst(skb);
if (dst && (dst->flags & DST_FAKE_RTABLE))
skb_dst_drop(skb);
}
#else
#define nf_bridge_maybe_copy_header(skb) (0)
#define nf_bridge_pad(skb) (0)
#define br_drop_fake_rtable(skb) do { } while (0)
#endif /* CONFIG_BRIDGE_NETFILTER */
#endif
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