[NETFILTER]: Kill nf_debug
[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  *      $Id: br_forward.c,v 1.4 2001/08/14 22:05:57 davem Exp $
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/netdevice.h>
18 #include <linux/skbuff.h>
19 #include <linux/netfilter_bridge.h>
20 #include "br_private.h"
21
22 static inline int should_deliver(const struct net_bridge_port *p, 
23                                  const struct sk_buff *skb)
24 {
25         if (skb->dev == p->dev ||
26             p->state != BR_STATE_FORWARDING)
27                 return 0;
28
29         return 1;
30 }
31
32 int br_dev_queue_push_xmit(struct sk_buff *skb)
33 {
34         if (skb->len > skb->dev->mtu) 
35                 kfree_skb(skb);
36         else {
37 #ifdef CONFIG_BRIDGE_NETFILTER
38                 /* ip_refrag calls ip_fragment, doesn't copy the MAC header. */
39                 nf_bridge_maybe_copy_header(skb);
40 #endif
41                 skb_push(skb, ETH_HLEN);
42
43                 dev_queue_xmit(skb);
44         }
45
46         return 0;
47 }
48
49 int br_forward_finish(struct sk_buff *skb)
50 {
51         NF_HOOK(PF_BRIDGE, NF_BR_POST_ROUTING, skb, NULL, skb->dev,
52                         br_dev_queue_push_xmit);
53
54         return 0;
55 }
56
57 static void __br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
58 {
59         skb->dev = to->dev;
60         NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
61                         br_forward_finish);
62 }
63
64 static void __br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
65 {
66         struct net_device *indev;
67
68         indev = skb->dev;
69         skb->dev = to->dev;
70         skb->ip_summed = CHECKSUM_NONE;
71
72         NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, indev, skb->dev,
73                         br_forward_finish);
74 }
75
76 /* called with rcu_read_lock */
77 void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
78 {
79         if (should_deliver(to, skb)) {
80                 __br_deliver(to, skb);
81                 return;
82         }
83
84         kfree_skb(skb);
85 }
86
87 /* called with rcu_read_lock */
88 void br_forward(const struct net_bridge_port *to, struct sk_buff *skb)
89 {
90         if (should_deliver(to, skb)) {
91                 __br_forward(to, skb);
92                 return;
93         }
94
95         kfree_skb(skb);
96 }
97
98 /* called under bridge lock */
99 static void br_flood(struct net_bridge *br, struct sk_buff *skb, int clone,
100         void (*__packet_hook)(const struct net_bridge_port *p, 
101                               struct sk_buff *skb))
102 {
103         struct net_bridge_port *p;
104         struct net_bridge_port *prev;
105
106         if (clone) {
107                 struct sk_buff *skb2;
108
109                 if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
110                         br->statistics.tx_dropped++;
111                         return;
112                 }
113
114                 skb = skb2;
115         }
116
117         prev = NULL;
118
119         list_for_each_entry_rcu(p, &br->port_list, list) {
120                 if (should_deliver(p, skb)) {
121                         if (prev != NULL) {
122                                 struct sk_buff *skb2;
123
124                                 if ((skb2 = skb_clone(skb, GFP_ATOMIC)) == NULL) {
125                                         br->statistics.tx_dropped++;
126                                         kfree_skb(skb);
127                                         return;
128                                 }
129
130                                 __packet_hook(prev, skb2);
131                         }
132
133                         prev = p;
134                 }
135         }
136
137         if (prev != NULL) {
138                 __packet_hook(prev, skb);
139                 return;
140         }
141
142         kfree_skb(skb);
143 }
144
145
146 /* called with rcu_read_lock */
147 void br_flood_deliver(struct net_bridge *br, struct sk_buff *skb, int clone)
148 {
149         br_flood(br, skb, clone, __br_deliver);
150 }
151
152 /* called under bridge lock */
153 void br_flood_forward(struct net_bridge *br, struct sk_buff *skb, int clone)
154 {
155         br_flood(br, skb, clone, __br_forward);
156 }