sky2: use DEFINE_PCI_DEVICE_TABLE
[linux-2.6] / net / bridge / br_forward.c
1 /*
2  *      Forwarding decision
3  *      Linux ethernet bridge
4  *
5  *      Authors:
6  *      Lennert Buytenhek               <buytenh@gnu.org>
7  *
8  *      This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/netdevice.h>
16 #include <linux/skbuff.h>
17 #include <linux/if_vlan.h>
18 #include <linux/netfilter_bridge.h>
19 #include "br_private.h"
20
21 /* Don't forward packets to originating port or forwarding diasabled */
22 static inline int should_deliver(const struct net_bridge_port *p,
23                                  const struct sk_buff *skb)
24 {
25         return (skb->dev != p->dev && p->state == BR_STATE_FORWARDING);
26 }
27
28 static inline unsigned packet_length(const struct sk_buff *skb)
29 {
30         return skb->len - (skb->protocol == htons(ETH_P_8021Q) ? VLAN_HLEN : 0);
31 }
32
33 int br_dev_queue_push_xmit(struct sk_buff *skb)
34 {
35         /* drop mtu oversized packets except gso */
36         if (packet_length(skb) > skb->dev->mtu && !skb_is_gso(skb))
37                 kfree_skb(skb);
38         else {
39                 /* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
40                 if (nf_bridge_maybe_copy_header(skb))
41                         kfree_skb(skb);
42                 else {
43                         skb_push(skb, ETH_HLEN);
44
45                         dev_queue_xmit(skb);
46                 }
47         }
48
49         return 0;
50 }
51
52 int br_forward_finish(struct sk_buff *skb)
53 {
54         return NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
55                        br_dev_queue_push_xmit);
56
57 }
58
59 static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
60 {
61         skb->dev = to->dev;
62         NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
63                         br_forward_finish);
64 }
65
66 static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
67 {
68         struct net_device *indev;
69
70         indev = skb->dev;
71         skb->dev = to->dev;
72         skb_forward_csum(skb);
73
74         NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
75                         br_forward_finish);
76 }
77
78 /* called with rcu_read_lock */
79 void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
80 {
81         if (should_deliver(to, skb)) {
82                 __br_deliver(to, skb);
83                 return;
84         }
85
86         kfree_skb(skb);
87 }
88
89 /* called with rcu_read_lock */
90 void br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
91 {
92         if (should_deliver(to, skb)) {
93                 __br_forward(to, skb);
94                 return;
95         }
96
97         kfree_skb(skb);
98 }
99
100 /* called under bridge lock */
101 static void br_flood(struct net_bridge *br, struct sk_buff *skb,
102         void (*__packet_hook)(const struct net_bridge_port *p,
103                               struct sk_buff *skb))
104 {
105         struct net_bridge_port *p;
106         struct net_bridge_port *prev;
107
108         prev = NULL;
109
110         list_for_each_entry_rcu(p, &br->port_list, list) {
111                 if (should_deliver(p, skb)) {
112                         if (prev != NULL) {
113                                 struct sk_buff *skb2;
114
115                                 if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
116                                         br->dev->stats.tx_dropped++;
117                                         kfree_skb(skb);
118                                         return;
119                                 }
120
121                                 __packet_hook(prev, skb2);
122                         }
123
124                         prev = p;
125                 }
126         }
127
128         if (prev != NULL) {
129                 __packet_hook(prev, skb);
130                 return;
131         }
132
133         kfree_skb(skb);
134 }
135
136
137 /* called with rcu_read_lock */
138 void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb)
139 {
140         br_flood(br, skb, __br_deliver);
141 }
142
143 /* called under bridge lock */
144 void br_flood_forward(struct net_bridge *br, struct sk_buff *skb)
145 {
146         br_flood(br, skb, __br_forward);
147 }