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1/*
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 */
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#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
28static int llc_stat_ev_rx_null_dsap_xid_c(struct sk_buff *skb)
29{
30 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
31
32 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
33 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
34 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID &&
35 !pdu->dsap; /* NULL DSAP value */
36}
37
38static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb)
39{
40 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
41
42 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
43 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
44 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST &&
45 !pdu->dsap; /* NULL DSAP */
46}
47
48static int llc_station_ac_send_xid_r(struct sk_buff *skb)
49{
50 u8 mac_da[ETH_ALEN], dsap;
51 int rc = 1;
52 struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
53 sizeof(struct llc_xid_info));
54
55 if (!nskb)
56 goto out;
57 llc_pdu_decode_sa(skb, mac_da);
58 llc_pdu_decode_ssap(skb, &dsap);
59 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
60 llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 127);
61 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
62 if (unlikely(rc))
63 goto free;
64 dev_queue_xmit(nskb);
65out:
66 return rc;
67free:
68 kfree_skb(nskb);
69 goto out;
70}
71
72static int llc_station_ac_send_test_r(struct sk_buff *skb)
73{
74 u8 mac_da[ETH_ALEN], dsap;
75 int rc = 1;
76 u32 data_size;
77 struct sk_buff *nskb;
78
79 /* The test request command is type U (llc_len = 3) */
80 data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
81 nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);
82
83 if (!nskb)
84 goto out;
85 llc_pdu_decode_sa(skb, mac_da);
86 llc_pdu_decode_ssap(skb, &dsap);
87 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
88 llc_pdu_init_as_test_rsp(nskb, skb);
89 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
90 if (unlikely(rc))
91 goto free;
92 dev_queue_xmit(nskb);
93out:
94 return rc;
95free:
96 kfree_skb(nskb);
97 goto out;
98}
99
100/**
101 * llc_station_rcv - send received pdu to the station state machine
102 * @skb: received frame.
103 *
104 * Sends data unit to station state machine.
105 */
106static void llc_station_rcv(struct sk_buff *skb)
107{
108 if (llc_stat_ev_rx_null_dsap_xid_c(skb))
109 llc_station_ac_send_xid_r(skb);
110 else if (llc_stat_ev_rx_null_dsap_test_c(skb))
111 llc_station_ac_send_test_r(skb);
112 kfree_skb(skb);
113}
114
115void __init llc_station_init(void)
116{
117 llc_set_station_handler(llc_station_rcv);
118}
119
120void llc_station_exit(void)
121{
122 llc_set_station_handler(NULL);
123}
1/*
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 */
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#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
28static int llc_stat_ev_rx_null_dsap_xid_c(struct sk_buff *skb)
29{
30 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
31
32 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
33 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
34 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID &&
35 !pdu->dsap; /* NULL DSAP value */
36}
37
38static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb)
39{
40 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
41
42 return LLC_PDU_IS_CMD(pdu) && /* command PDU */
43 LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */
44 LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST &&
45 !pdu->dsap; /* NULL DSAP */
46}
47
48static int llc_station_ac_send_xid_r(struct sk_buff *skb)
49{
50 u8 mac_da[ETH_ALEN], dsap;
51 int rc = 1;
52 struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
53 sizeof(struct llc_xid_info));
54
55 if (!nskb)
56 goto out;
57 llc_pdu_decode_sa(skb, mac_da);
58 llc_pdu_decode_ssap(skb, &dsap);
59 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
60 llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 127);
61 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
62 if (unlikely(rc))
63 goto free;
64 dev_queue_xmit(nskb);
65out:
66 return rc;
67free:
68 kfree_skb(nskb);
69 goto out;
70}
71
72static int llc_station_ac_send_test_r(struct sk_buff *skb)
73{
74 u8 mac_da[ETH_ALEN], dsap;
75 int rc = 1;
76 u32 data_size;
77 struct sk_buff *nskb;
78
79 if (skb->mac_len < ETH_HLEN)
80 goto out;
81
82 /* The test request command is type U (llc_len = 3) */
83 data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
84 nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);
85
86 if (!nskb)
87 goto out;
88 llc_pdu_decode_sa(skb, mac_da);
89 llc_pdu_decode_ssap(skb, &dsap);
90 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
91 llc_pdu_init_as_test_rsp(nskb, skb);
92 rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
93 if (unlikely(rc))
94 goto free;
95 dev_queue_xmit(nskb);
96out:
97 return rc;
98free:
99 kfree_skb(nskb);
100 goto out;
101}
102
103/**
104 * llc_station_rcv - send received pdu to the station state machine
105 * @skb: received frame.
106 *
107 * Sends data unit to station state machine.
108 */
109static void llc_station_rcv(struct sk_buff *skb)
110{
111 if (llc_stat_ev_rx_null_dsap_xid_c(skb))
112 llc_station_ac_send_xid_r(skb);
113 else if (llc_stat_ev_rx_null_dsap_test_c(skb))
114 llc_station_ac_send_test_r(skb);
115 kfree_skb(skb);
116}
117
118void __init llc_station_init(void)
119{
120 llc_set_station_handler(llc_station_rcv);
121}
122
123void llc_station_exit(void)
124{
125 llc_set_station_handler(NULL);
126}