blob: b88220a64cd8e0a7009971cc09f6507fc3f9b117 [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{
Stephen Hemminger7ce54e32005-05-29 14:16:48 -070026 netif_receive_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 return 0;
28}
29
30static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
31{
32 struct net_device *indev;
33
34 br->statistics.rx_packets++;
35 br->statistics.rx_bytes += skb->len;
36
37 indev = skb->dev;
38 skb->dev = br->dev;
39
40 NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL,
41 br_pass_frame_up_finish);
42}
43
44/* note: already called with rcu_read_lock (preempt_disabled) */
45int br_handle_frame_finish(struct sk_buff *skb)
46{
47 const unsigned char *dest = eth_hdr(skb)->h_dest;
48 struct net_bridge_port *p = skb->dev->br_port;
49 struct net_bridge *br = p->br;
50 struct net_bridge_fdb_entry *dst;
51 int passedup = 0;
52
Stephen Hemminger85967bb2005-05-29 14:15:55 -070053 /* insert into forwarding database after filtering to avoid spoofing */
54 br_fdb_update(p->br, p, eth_hdr(skb)->h_source);
55
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 if (br->dev->flags & IFF_PROMISC) {
57 struct sk_buff *skb2;
58
59 skb2 = skb_clone(skb, GFP_ATOMIC);
60 if (skb2 != NULL) {
61 passedup = 1;
62 br_pass_frame_up(br, skb2);
63 }
64 }
65
66 if (dest[0] & 1) {
67 br_flood_forward(br, skb, !passedup);
68 if (!passedup)
69 br_pass_frame_up(br, skb);
70 goto out;
71 }
72
73 dst = __br_fdb_get(br, dest);
74 if (dst != NULL && dst->is_local) {
75 if (!passedup)
76 br_pass_frame_up(br, skb);
77 else
78 kfree_skb(skb);
79 goto out;
80 }
81
82 if (dst != NULL) {
83 br_forward(dst->dst, skb);
84 goto out;
85 }
86
87 br_flood_forward(br, skb, 0);
88
89out:
90 return 0;
91}
92
93/*
94 * Called via br_handle_frame_hook.
95 * Return 0 if *pskb should be processed furthur
96 * 1 if *pskb is handled
97 * note: already called with rcu_read_lock (preempt_disabled)
98 */
99int br_handle_frame(struct net_bridge_port *p, struct sk_buff **pskb)
100{
101 struct sk_buff *skb = *pskb;
102 const unsigned char *dest = eth_hdr(skb)->h_dest;
103
104 if (p->state == BR_STATE_DISABLED)
105 goto err;
106
107 if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
108 goto err;
109
Stephen Hemminger85967bb2005-05-29 14:15:55 -0700110 if (p->state == BR_STATE_LEARNING)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 br_fdb_update(p->br, p, eth_hdr(skb)->h_source);
112
113 if (p->br->stp_enabled &&
114 !memcmp(dest, bridge_ula, 5) &&
115 !(dest[5] & 0xF0)) {
116 if (!dest[5]) {
117 NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev,
118 NULL, br_stp_handle_bpdu);
119 return 1;
120 }
121 }
122
123 else if (p->state == BR_STATE_FORWARDING) {
124 if (br_should_route_hook) {
125 if (br_should_route_hook(pskb))
126 return 0;
127 skb = *pskb;
128 dest = eth_hdr(skb)->h_dest;
129 }
130
Stephen Hemminger6ede2462005-10-25 15:04:59 -0700131 if (!compare_ether_addr(p->br->dev->dev_addr, dest))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 skb->pkt_type = PACKET_HOST;
133
134 NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
135 br_handle_frame_finish);
136 return 1;
137 }
138
139err:
140 kfree_skb(skb);
141 return 1;
142}