blob: 204a8351efffc86f566e51b27f173c8bdee6c4cb [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * llc_station.c - station component of LLC
3 *
4 * Copyright (c) 1997 by Procom Technology, Inc.
5 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
6 *
7 * This program can be redistributed or modified under the terms of the
8 * GNU General Public License as published by the Free Software Foundation.
9 * This program is distributed without any warranty or implied warranty
10 * of merchantability or fitness for a particular purpose.
11 *
12 * See the GNU General Public License for more details.
13 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/init.h>
15#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090016#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <net/llc.h>
18#include <net/llc_sap.h>
19#include <net/llc_conn.h>
20#include <net/llc_c_ac.h>
21#include <net/llc_s_ac.h>
22#include <net/llc_c_ev.h>
23#include <net/llc_c_st.h>
24#include <net/llc_s_ev.h>
25#include <net/llc_s_st.h>
26#include <net/llc_pdu.h>
27
Linus Torvalds1da177e2005-04-16 15:20:36 -070028static int llc_stat_ev_rx_null_dsap_xid_c(struct sk_buff *skb)
29{
Linus Torvalds1da177e2005-04-16 15:20:36 -070030 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
31
Ben Hutchings025e3632012-09-15 17:11:18 +000032 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
Linus Torvalds1da177e2005-04-16 15:20:36 -070033 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
34 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID &&
35 !pdu->dsap ? 0 : 1; /* NULL DSAP value */
36}
37
Linus Torvalds1da177e2005-04-16 15:20:36 -070038static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb)
39{
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
41
Ben Hutchings025e3632012-09-15 17:11:18 +000042 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
44 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST &&
45 !pdu->dsap ? 0 : 1; /* NULL DSAP */
46}
47
Linus Torvalds1da177e2005-04-16 15:20:36 -070048static int llc_station_ac_send_xid_r(struct sk_buff *skb)
49{
50 u8 mac_da[ETH_ALEN], dsap;
51 int rc = 1;
Joonwoo Parkf83f1762008-03-31 21:02:47 -070052 struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
53 sizeof(struct llc_xid_info));
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55 if (!nskb)
56 goto out;
57 rc = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 llc_pdu_decode_sa(skb, mac_da);
59 llc_pdu_decode_ssap(skb, &dsap);
60 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
61 llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 127);
Joonwoo Parka5a04812008-03-28 16:28:36 -070062 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
Arnaldo Carvalho de Melo249ff1c2005-09-22 04:32:10 -030063 if (unlikely(rc))
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 goto free;
Ben Hutchings5ecf9ee2012-09-15 17:11:32 +000065 dev_queue_xmit(nskb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070066out:
67 return rc;
68free:
Sorin Dumitru91d27a82012-08-06 02:35:58 +000069 kfree_skb(nskb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 goto out;
71}
72
73static int llc_station_ac_send_test_r(struct sk_buff *skb)
74{
75 u8 mac_da[ETH_ALEN], dsap;
76 int rc = 1;
Joonwoo Parkf83f1762008-03-31 21:02:47 -070077 u32 data_size;
78 struct sk_buff *nskb;
79
80 /* The test request command is type U (llc_len = 3) */
81 data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
82 nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84 if (!nskb)
85 goto out;
86 rc = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 llc_pdu_decode_sa(skb, mac_da);
88 llc_pdu_decode_ssap(skb, &dsap);
89 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
YOSHIFUJI Hideakid57b1862007-02-09 23:25:01 +090090 llc_pdu_init_as_test_rsp(nskb, skb);
Joonwoo Parka5a04812008-03-28 16:28:36 -070091 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
Arnaldo Carvalho de Melo249ff1c2005-09-22 04:32:10 -030092 if (unlikely(rc))
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 goto free;
Ben Hutchings5ecf9ee2012-09-15 17:11:32 +000094 dev_queue_xmit(nskb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095out:
96 return rc;
97free:
Sorin Dumitru91d27a82012-08-06 02:35:58 +000098 kfree_skb(nskb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 goto out;
100}
101
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 * llc_station_rcv - send received pdu to the station state machine
104 * @skb: received frame.
105 *
106 * Sends data unit to station state machine.
107 */
108static void llc_station_rcv(struct sk_buff *skb)
109{
Ben Hutchings12ebc8b2012-09-15 17:11:47 +0000110 if (llc_stat_ev_rx_null_dsap_xid_c(skb))
111 llc_station_ac_send_xid_r(skb);
112 else if (llc_stat_ev_rx_null_dsap_test_c(skb))
113 llc_station_ac_send_test_r(skb);
Ben Hutchings04d191c2012-09-15 17:11:25 +0000114 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115}
116
Ben Hutchings60249352012-08-13 02:49:59 +0000117void __init llc_station_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118{
Ben Hutchingsaadf31d2012-08-13 02:50:55 +0000119 llc_set_station_handler(llc_station_rcv);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120}
121
Ben Hutchingsf4f87202012-08-13 02:50:43 +0000122void llc_station_exit(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123{
124 llc_set_station_handler(NULL);
125}