Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Handle incoming frames |
| 3 | * Linux ethernet bridge |
| 4 | * |
| 5 | * Authors: |
| 6 | * Lennert Buytenhek <buytenh@gnu.org> |
| 7 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/kernel.h> |
| 16 | #include <linux/netdevice.h> |
| 17 | #include <linux/etherdevice.h> |
| 18 | #include <linux/netfilter_bridge.h> |
| 19 | #include "br_private.h" |
| 20 | |
Stephen Hemminger | fda93d9 | 2006-03-20 22:59:21 -0800 | [diff] [blame] | 21 | /* Bridge group multicast address 802.1d (pg 51). */ |
| 22 | const u8 br_group_address[ETH_ALEN] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | |
Herbert Xu | 68b7c89 | 2010-02-27 19:41:40 +0000 | [diff] [blame] | 24 | static int br_pass_frame_up(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | { |
Herbert Xu | 68b7c89 | 2010-02-27 19:41:40 +0000 | [diff] [blame] | 26 | struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev; |
stephen hemminger | 14bb478 | 2010-03-02 13:32:09 +0000 | [diff] [blame] | 27 | struct net_bridge *br = netdev_priv(brdev); |
| 28 | struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
Eric Dumazet | 406818f | 2010-06-23 13:00:48 -0700 | [diff] [blame] | 30 | u64_stats_update_begin(&brstats->syncp); |
stephen hemminger | 14bb478 | 2010-03-02 13:32:09 +0000 | [diff] [blame] | 31 | brstats->rx_packets++; |
| 32 | brstats->rx_bytes += skb->len; |
Eric Dumazet | 406818f | 2010-06-23 13:00:48 -0700 | [diff] [blame] | 33 | u64_stats_update_end(&brstats->syncp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
| 35 | indev = skb->dev; |
Pavel Emelyanov | a339f1c | 2008-05-21 14:13:47 -0700 | [diff] [blame] | 36 | skb->dev = brdev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
Jan Engelhardt | 713aefa | 2010-03-23 04:07:21 +0100 | [diff] [blame] | 38 | return NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL, |
Herbert Xu | 68b7c89 | 2010-02-27 19:41:40 +0000 | [diff] [blame] | 39 | netif_receive_skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | } |
| 41 | |
stephen hemminger | eeaf61d | 2010-07-27 08:26:30 +0000 | [diff] [blame] | 42 | /* note: already called with rcu_read_lock */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | int br_handle_frame_finish(struct sk_buff *skb) |
| 44 | { |
| 45 | const unsigned char *dest = eth_hdr(skb)->h_dest; |
Jiri Pirko | f350a0a | 2010-06-15 06:50:45 +0000 | [diff] [blame] | 46 | struct net_bridge_port *p = br_port_get_rcu(skb->dev); |
Stephen Hemminger | b3f1be4 | 2006-02-09 17:08:52 -0800 | [diff] [blame] | 47 | struct net_bridge *br; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | struct net_bridge_fdb_entry *dst; |
Herbert Xu | c4fcb78 | 2010-02-27 19:41:48 +0000 | [diff] [blame] | 49 | struct net_bridge_mdb_entry *mdst; |
Herbert Xu | e081e1e | 2007-09-16 16:20:48 -0700 | [diff] [blame] | 50 | struct sk_buff *skb2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Stephen Hemminger | b3f1be4 | 2006-02-09 17:08:52 -0800 | [diff] [blame] | 52 | if (!p || p->state == BR_STATE_DISABLED) |
| 53 | goto drop; |
Stephen Hemminger | 85967bb | 2005-05-29 14:15:55 -0700 | [diff] [blame] | 54 | |
Stephen Hemminger | b3f1be4 | 2006-02-09 17:08:52 -0800 | [diff] [blame] | 55 | /* insert into forwarding database after filtering to avoid spoofing */ |
| 56 | br = p->br; |
| 57 | br_fdb_update(br, p, eth_hdr(skb)->h_source); |
| 58 | |
Herbert Xu | c4fcb78 | 2010-02-27 19:41:48 +0000 | [diff] [blame] | 59 | if (is_multicast_ether_addr(dest) && |
| 60 | br_multicast_rcv(br, p, skb)) |
| 61 | goto drop; |
| 62 | |
Stephen Hemminger | b3f1be4 | 2006-02-09 17:08:52 -0800 | [diff] [blame] | 63 | if (p->state == BR_STATE_LEARNING) |
| 64 | goto drop; |
Stephen Hemminger | 0e5eaba | 2005-12-21 19:00:18 -0800 | [diff] [blame] | 65 | |
Herbert Xu | 68b7c89 | 2010-02-27 19:41:40 +0000 | [diff] [blame] | 66 | BR_INPUT_SKB_CB(skb)->brdev = br->dev; |
| 67 | |
Herbert Xu | e081e1e | 2007-09-16 16:20:48 -0700 | [diff] [blame] | 68 | /* The packet skb2 goes to the local host (NULL to skip). */ |
| 69 | skb2 = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | |
Herbert Xu | e081e1e | 2007-09-16 16:20:48 -0700 | [diff] [blame] | 71 | if (br->dev->flags & IFF_PROMISC) |
| 72 | skb2 = skb; |
| 73 | |
| 74 | dst = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | |
Kris Katterjohn | dbbc098 | 2006-01-06 13:05:58 -0800 | [diff] [blame] | 76 | if (is_multicast_ether_addr(dest)) { |
Herbert Xu | c4fcb78 | 2010-02-27 19:41:48 +0000 | [diff] [blame] | 77 | mdst = br_mdb_get(br, skb); |
YOSHIFUJI Hideaki / 吉藤英明 | 32dec5d | 2010-03-15 21:51:18 +0000 | [diff] [blame] | 78 | if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) { |
Herbert Xu | c4fcb78 | 2010-02-27 19:41:48 +0000 | [diff] [blame] | 79 | if ((mdst && !hlist_unhashed(&mdst->mglist)) || |
| 80 | br_multicast_is_router(br)) |
| 81 | skb2 = skb; |
| 82 | br_multicast_forward(mdst, skb, skb2); |
| 83 | skb = NULL; |
| 84 | if (!skb2) |
| 85 | goto out; |
| 86 | } else |
| 87 | skb2 = skb; |
| 88 | |
Pavel Emelyanov | a339f1c | 2008-05-21 14:13:47 -0700 | [diff] [blame] | 89 | br->dev->stats.multicast++; |
Herbert Xu | e081e1e | 2007-09-16 16:20:48 -0700 | [diff] [blame] | 90 | } else if ((dst = __br_fdb_get(br, dest)) && dst->is_local) { |
| 91 | skb2 = skb; |
| 92 | /* Do not forward the packet since it's local. */ |
| 93 | skb = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | } |
| 95 | |
Herbert Xu | e081e1e | 2007-09-16 16:20:48 -0700 | [diff] [blame] | 96 | if (skb) { |
| 97 | if (dst) |
Michael Braun | 7f7708f | 2010-03-16 00:26:22 -0700 | [diff] [blame] | 98 | br_forward(dst->dst, skb, skb2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | else |
Herbert Xu | b33084b | 2010-02-27 19:41:41 +0000 | [diff] [blame] | 100 | br_flood_forward(br, skb, skb2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | } |
| 102 | |
Herbert Xu | 87557c1 | 2010-02-27 19:41:39 +0000 | [diff] [blame] | 103 | if (skb2) |
Herbert Xu | 68b7c89 | 2010-02-27 19:41:40 +0000 | [diff] [blame] | 104 | return br_pass_frame_up(skb2); |
Herbert Xu | 87557c1 | 2010-02-27 19:41:39 +0000 | [diff] [blame] | 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | out: |
| 107 | return 0; |
Stephen Hemminger | b3f1be4 | 2006-02-09 17:08:52 -0800 | [diff] [blame] | 108 | drop: |
| 109 | kfree_skb(skb); |
| 110 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | } |
| 112 | |
stephen hemminger | eeaf61d | 2010-07-27 08:26:30 +0000 | [diff] [blame] | 113 | /* note: already called with rcu_read_lock */ |
Stephen Hemminger | cf0f02d | 2006-03-20 22:59:06 -0800 | [diff] [blame] | 114 | static int br_handle_local_finish(struct sk_buff *skb) |
| 115 | { |
Jiri Pirko | f350a0a | 2010-06-15 06:50:45 +0000 | [diff] [blame] | 116 | struct net_bridge_port *p = br_port_get_rcu(skb->dev); |
Stephen Hemminger | cf0f02d | 2006-03-20 22:59:06 -0800 | [diff] [blame] | 117 | |
Jiri Pirko | f350a0a | 2010-06-15 06:50:45 +0000 | [diff] [blame] | 118 | br_fdb_update(p->br, p, eth_hdr(skb)->h_source); |
Stephen Hemminger | cf0f02d | 2006-03-20 22:59:06 -0800 | [diff] [blame] | 119 | return 0; /* process further */ |
| 120 | } |
| 121 | |
| 122 | /* Does address match the link local multicast address. |
| 123 | * 01:80:c2:00:00:0X |
| 124 | */ |
Andrew Morton | b3e83d6 | 2006-03-20 23:00:56 -0800 | [diff] [blame] | 125 | static inline int is_link_local(const unsigned char *dest) |
Stephen Hemminger | cf0f02d | 2006-03-20 22:59:06 -0800 | [diff] [blame] | 126 | { |
Al Viro | 582ee43 | 2007-07-26 17:33:39 +0100 | [diff] [blame] | 127 | __be16 *a = (__be16 *)dest; |
| 128 | static const __be16 *b = (const __be16 *)br_group_address; |
YOSHIFUJI Hideaki | 91c5ec3 | 2007-12-12 03:51:03 +0900 | [diff] [blame] | 129 | static const __be16 m = cpu_to_be16(0xfff0); |
Stephen Hemminger | fd74e6c | 2007-03-12 16:25:32 -0700 | [diff] [blame] | 130 | |
| 131 | return ((a[0] ^ b[0]) | (a[1] ^ b[1]) | ((a[2] ^ b[2]) & m)) == 0; |
Stephen Hemminger | cf0f02d | 2006-03-20 22:59:06 -0800 | [diff] [blame] | 132 | } |
| 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | /* |
Stephen Hemminger | 6229e36 | 2007-03-21 13:38:47 -0700 | [diff] [blame] | 135 | * Return NULL if skb is handled |
stephen hemminger | eeaf61d | 2010-07-27 08:26:30 +0000 | [diff] [blame] | 136 | * note: already called with rcu_read_lock |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | */ |
Jiri Pirko | ab95bfe | 2010-06-01 21:52:08 +0000 | [diff] [blame] | 138 | struct sk_buff *br_handle_frame(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | { |
Jiri Pirko | ab95bfe | 2010-06-01 21:52:08 +0000 | [diff] [blame] | 140 | struct net_bridge_port *p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | const unsigned char *dest = eth_hdr(skb)->h_dest; |
Pavel Emelyanov | 82de382 | 2007-11-29 23:58:58 +1100 | [diff] [blame] | 142 | int (*rhook)(struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | |
Simon Horman | c2368e7 | 2010-08-22 17:35:32 +0000 | [diff] [blame] | 144 | if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) |
Jiri Pirko | ab95bfe | 2010-06-01 21:52:08 +0000 | [diff] [blame] | 145 | return skb; |
| 146 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | if (!is_valid_ether_addr(eth_hdr(skb)->h_source)) |
Stephen Hemminger | 467aea0 | 2007-03-21 13:42:06 -0700 | [diff] [blame] | 148 | goto drop; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | |
Herbert Xu | 7b99565 | 2007-10-14 00:39:01 -0700 | [diff] [blame] | 150 | skb = skb_share_check(skb, GFP_ATOMIC); |
| 151 | if (!skb) |
| 152 | return NULL; |
| 153 | |
Jiri Pirko | f350a0a | 2010-06-15 06:50:45 +0000 | [diff] [blame] | 154 | p = br_port_get_rcu(skb->dev); |
Jiri Pirko | ab95bfe | 2010-06-01 21:52:08 +0000 | [diff] [blame] | 155 | |
Stephen Hemminger | 2111f8b | 2007-04-25 22:05:55 -0700 | [diff] [blame] | 156 | if (unlikely(is_link_local(dest))) { |
| 157 | /* Pause frames shouldn't be passed up by driver anyway */ |
| 158 | if (skb->protocol == htons(ETH_P_PAUSE)) |
| 159 | goto drop; |
| 160 | |
Stephen Hemminger | a598f6a | 2009-05-15 06:10:13 +0000 | [diff] [blame] | 161 | /* If STP is turned off, then forward */ |
Benjamin Poirier | 1e253c3 | 2010-10-18 16:09:35 +0000 | [diff] [blame] | 162 | if (p->br->stp_enabled == BR_NO_STP) |
Stephen Hemminger | a598f6a | 2009-05-15 06:10:13 +0000 | [diff] [blame] | 163 | goto forward; |
| 164 | |
Jan Engelhardt | 713aefa | 2010-03-23 04:07:21 +0100 | [diff] [blame] | 165 | if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev, |
Stephen Hemminger | 43aa192 | 2008-06-17 16:09:45 -0700 | [diff] [blame] | 166 | NULL, br_handle_local_finish)) |
| 167 | return NULL; /* frame consumed by filter */ |
| 168 | else |
| 169 | return skb; /* continue processing */ |
Stephen Hemminger | 2111f8b | 2007-04-25 22:05:55 -0700 | [diff] [blame] | 170 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Stephen Hemminger | a598f6a | 2009-05-15 06:10:13 +0000 | [diff] [blame] | 172 | forward: |
Stephen Hemminger | 467aea0 | 2007-03-21 13:42:06 -0700 | [diff] [blame] | 173 | switch (p->state) { |
| 174 | case BR_STATE_FORWARDING: |
Pavel Emelyanov | 82de382 | 2007-11-29 23:58:58 +1100 | [diff] [blame] | 175 | rhook = rcu_dereference(br_should_route_hook); |
| 176 | if (rhook != NULL) { |
| 177 | if (rhook(skb)) |
Stephen Hemminger | 6229e36 | 2007-03-21 13:38:47 -0700 | [diff] [blame] | 178 | return skb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | dest = eth_hdr(skb)->h_dest; |
| 180 | } |
Stephen Hemminger | 467aea0 | 2007-03-21 13:42:06 -0700 | [diff] [blame] | 181 | /* fall through */ |
| 182 | case BR_STATE_LEARNING: |
Stephen Hemminger | 6ede246 | 2005-10-25 15:04:59 -0700 | [diff] [blame] | 183 | if (!compare_ether_addr(p->br->dev->dev_addr, dest)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | skb->pkt_type = PACKET_HOST; |
| 185 | |
Jan Engelhardt | 713aefa | 2010-03-23 04:07:21 +0100 | [diff] [blame] | 186 | NF_HOOK(NFPROTO_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | br_handle_frame_finish); |
Stephen Hemminger | 467aea0 | 2007-03-21 13:42:06 -0700 | [diff] [blame] | 188 | break; |
| 189 | default: |
| 190 | drop: |
| 191 | kfree_skb(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | } |
Stephen Hemminger | 6229e36 | 2007-03-21 13:38:47 -0700 | [diff] [blame] | 193 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | } |