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authorLinus Torvalds <torvalds@linux-foundation.org>2008-07-20 20:43:29 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-20 20:43:29 -0400
commitdb6d8c7a4027b48d797b369a53f8470aaeed7063 (patch)
treee140c104a89abc2154e1f41a7db8ebecbb6fa0b4 /net/802/stp.c
parent3a533374283aea50eab3976d8a6d30532175f009 (diff)
parentfb65a7c091529bfffb1262515252c0d0f6241c5c (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (1232 commits) iucv: Fix bad merging. net_sched: Add size table for qdiscs net_sched: Add accessor function for packet length for qdiscs net_sched: Add qdisc_enqueue wrapper highmem: Export totalhigh_pages. ipv6 mcast: Omit redundant address family checks in ip6_mc_source(). net: Use standard structures for generic socket address structures. ipv6 netns: Make several "global" sysctl variables namespace aware. netns: Use net_eq() to compare net-namespaces for optimization. ipv6: remove unused macros from net/ipv6.h ipv6: remove unused parameter from ip6_ra_control tcp: fix kernel panic with listening_get_next tcp: Remove redundant checks when setting eff_sacks tcp: options clean up tcp: Fix MD5 signatures for non-linear skbs sctp: Update sctp global memory limit allocations. sctp: remove unnecessary byteshifting, calculate directly in big-endian sctp: Allow only 1 listening socket with SO_REUSEADDR sctp: Do not leak memory on multiple listen() calls sctp: Support ipv6only AF_INET6 sockets. ...
Diffstat (limited to 'net/802/stp.c')
-rw-r--r--net/802/stp.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/net/802/stp.c b/net/802/stp.c
new file mode 100644
index 000000000000..0b7a24452d11
--- /dev/null
+++ b/net/802/stp.c
@@ -0,0 +1,102 @@
1/*
2 * STP SAP demux
3 *
4 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * version 2 as published by the Free Software Foundation.
9 */
10#include <linux/mutex.h>
11#include <linux/skbuff.h>
12#include <linux/etherdevice.h>
13#include <linux/llc.h>
14#include <net/llc.h>
15#include <net/llc_pdu.h>
16#include <net/stp.h>
17
18/* 01:80:c2:00:00:20 - 01:80:c2:00:00:2F */
19#define GARP_ADDR_MIN 0x20
20#define GARP_ADDR_MAX 0x2F
21#define GARP_ADDR_RANGE (GARP_ADDR_MAX - GARP_ADDR_MIN)
22
23static const struct stp_proto *garp_protos[GARP_ADDR_RANGE + 1] __read_mostly;
24static const struct stp_proto *stp_proto __read_mostly;
25
26static struct llc_sap *sap __read_mostly;
27static unsigned int sap_registered;
28static DEFINE_MUTEX(stp_proto_mutex);
29
30/* Called under rcu_read_lock from LLC */
31static int stp_pdu_rcv(struct sk_buff *skb, struct net_device *dev,
32 struct packet_type *pt, struct net_device *orig_dev)
33{
34 const struct ethhdr *eh = eth_hdr(skb);
35 const struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
36 const struct stp_proto *proto;
37
38 if (pdu->ssap != LLC_SAP_BSPAN ||
39 pdu->dsap != LLC_SAP_BSPAN ||
40 pdu->ctrl_1 != LLC_PDU_TYPE_U)
41 goto err;
42
43 if (eh->h_dest[5] >= GARP_ADDR_MIN && eh->h_dest[5] <= GARP_ADDR_MAX) {
44 proto = rcu_dereference(garp_protos[eh->h_dest[5] -
45 GARP_ADDR_MIN]);
46 if (proto &&
47 compare_ether_addr(eh->h_dest, proto->group_address))
48 goto err;
49 } else
50 proto = rcu_dereference(stp_proto);
51
52 if (!proto)
53 goto err;
54
55 proto->rcv(proto, skb, dev);
56 return 0;
57
58err:
59 kfree_skb(skb);
60 return 0;
61}
62
63int stp_proto_register(const struct stp_proto *proto)
64{
65 int err = 0;
66
67 mutex_lock(&stp_proto_mutex);
68 if (sap_registered++ == 0) {
69 sap = llc_sap_open(LLC_SAP_BSPAN, stp_pdu_rcv);
70 if (!sap) {
71 err = -ENOMEM;
72 goto out;
73 }
74 }
75 if (is_zero_ether_addr(proto->group_address))
76 rcu_assign_pointer(stp_proto, proto);
77 else
78 rcu_assign_pointer(garp_protos[proto->group_address[5] -
79 GARP_ADDR_MIN], proto);
80out:
81 mutex_unlock(&stp_proto_mutex);
82 return err;
83}
84EXPORT_SYMBOL_GPL(stp_proto_register);
85
86void stp_proto_unregister(const struct stp_proto *proto)
87{
88 mutex_lock(&stp_proto_mutex);
89 if (is_zero_ether_addr(proto->group_address))
90 rcu_assign_pointer(stp_proto, NULL);
91 else
92 rcu_assign_pointer(garp_protos[proto->group_address[5] -
93 GARP_ADDR_MIN], NULL);
94 synchronize_rcu();
95
96 if (--sap_registered == 0)
97 llc_sap_put(sap);
98 mutex_unlock(&stp_proto_mutex);
99}
100EXPORT_SYMBOL_GPL(stp_proto_unregister);
101
102MODULE_LICENSE("GPL");