blob: 2b1cce46cab42f71faee654e91c9fdfc2a224551 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Handle incoming frames
3 * Linux ethernet bridge
4 *
5 * Authors:
6 * Lennert Buytenhek <buytenh@gnu.org>
7 *
8 * $Id: br_input.c,v 1.10 2001/12/24 04:50:20 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/etherdevice.h>
19#include <linux/netfilter_bridge.h>
20#include "br_private.h"
21
22const unsigned char bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
23
24static int br_pass_frame_up_finish(struct sk_buff *skb)
25{
26#ifdef CONFIG_NETFILTER_DEBUG
27 skb->nf_debug = 0;
28#endif
29 netif_rx(skb);
30
31 return 0;
32}
33
34static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
35{
36 struct net_device *indev;
37
38 br->statistics.rx_packets++;
39 br->statistics.rx_bytes += skb->len;
40
41 indev = skb->dev;
42 skb->dev = br->dev;
43
44 NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL,
45 br_pass_frame_up_finish);
46}
47
48/* note: already called with rcu_read_lock (preempt_disabled) */
49int br_handle_frame_finish(struct sk_buff *skb)
50{
51 const unsigned char *dest = eth_hdr(skb)->h_dest;
52 struct net_bridge_port *p = skb->dev->br_port;
53 struct net_bridge *br = p->br;
54 struct net_bridge_fdb_entry *dst;
55 int passedup = 0;
56
57 if (br->dev->flags & IFF_PROMISC) {
58 struct sk_buff *skb2;
59
60 skb2 = skb_clone(skb, GFP_ATOMIC);
61 if (skb2 != NULL) {
62 passedup = 1;
63 br_pass_frame_up(br, skb2);
64 }
65 }
66
67 if (dest[0] & 1) {
68 br_flood_forward(br, skb, !passedup);
69 if (!passedup)
70 br_pass_frame_up(br, skb);
71 goto out;
72 }
73
74 dst = __br_fdb_get(br, dest);
75 if (dst != NULL && dst->is_local) {
76 if (!passedup)
77 br_pass_frame_up(br, skb);
78 else
79 kfree_skb(skb);
80 goto out;
81 }
82
83 if (dst != NULL) {
84 br_forward(dst->dst, skb);
85 goto out;
86 }
87
88 br_flood_forward(br, skb, 0);
89
90out:
91 return 0;
92}
93
94/*
95 * Called via br_handle_frame_hook.
96 * Return 0 if *pskb should be processed furthur
97 * 1 if *pskb is handled
98 * note: already called with rcu_read_lock (preempt_disabled)
99 */
100int br_handle_frame(struct net_bridge_port *p, struct sk_buff **pskb)
101{
102 struct sk_buff *skb = *pskb;
103 const unsigned char *dest = eth_hdr(skb)->h_dest;
104
105 if (p->state == BR_STATE_DISABLED)
106 goto err;
107
108 if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
109 goto err;
110
111 if (p->state == BR_STATE_LEARNING ||
112 p->state == BR_STATE_FORWARDING)
113 br_fdb_update(p->br, p, eth_hdr(skb)->h_source);
114
115 if (p->br->stp_enabled &&
116 !memcmp(dest, bridge_ula, 5) &&
117 !(dest[5] & 0xF0)) {
118 if (!dest[5]) {
119 NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev,
120 NULL, br_stp_handle_bpdu);
121 return 1;
122 }
123 }
124
125 else if (p->state == BR_STATE_FORWARDING) {
126 if (br_should_route_hook) {
127 if (br_should_route_hook(pskb))
128 return 0;
129 skb = *pskb;
130 dest = eth_hdr(skb)->h_dest;
131 }
132
133 if (!memcmp(p->br->dev->dev_addr, dest, ETH_ALEN))
134 skb->pkt_type = PACKET_HOST;
135
136 NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
137 br_handle_frame_finish);
138 return 1;
139 }
140
141err:
142 kfree_skb(skb);
143 return 1;
144}