]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
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; | |
1da177e4 LT |
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 | } |