1/*
2 * llc_s_ac.c - actions performed during sap state transition.
3 *
4 * Description :
5 * Functions in this module are implementation of sap component actions.
6 * Details of actions can be found in IEEE-802.2 standard document.
7 * All functions have one sap and one event as input argument. All of
8 * them return 0 On success and 1 otherwise.
9 *
10 * Copyright (c) 1997 by Procom Technology, Inc.
11 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
12 *
13 * This program can be redistributed or modified under the terms of the
14 * GNU General Public License as published by the Free Software Foundation.
15 * This program is distributed without any warranty or implied warranty
16 * of merchantability or fitness for a particular purpose.
17 *
18 * See the GNU General Public License for more details.
19 */
20
21#include <linux/netdevice.h>
22#include <net/llc.h>
23#include <net/llc_pdu.h>
24#include <net/llc_s_ac.h>
25#include <net/llc_s_ev.h>
26#include <net/llc_sap.h>
27
28
29/**
30 * llc_sap_action_unitdata_ind - forward UI PDU to network layer
31 * @sap: SAP
32 * @skb: the event to forward
33 *
34 * Received a UI PDU from MAC layer; forward to network layer as a
35 * UNITDATA INDICATION; verify our event is the kind we expect
36 */
37int llc_sap_action_unitdata_ind(struct llc_sap *sap, struct sk_buff *skb)
38{
39 llc_sap_rtn_pdu(sap, skb);
40 return 0;
41}
42
43/**
44 * llc_sap_action_send_ui - sends UI PDU resp to UNITDATA REQ to MAC layer
45 * @sap: SAP
46 * @skb: the event to send
47 *
48 * Sends a UI PDU to the MAC layer in response to a UNITDATA REQUEST
49 * primitive from the network layer. Verifies event is a primitive type of
50 * event. Verify the primitive is a UNITDATA REQUEST.
51 */
52int llc_sap_action_send_ui(struct llc_sap *sap, struct sk_buff *skb)
53{
54 struct llc_sap_state_ev *ev = llc_sap_ev(skb);
55 int rc;
56
57 llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ssap: ev->saddr.lsap,
58 dsap: ev->daddr.lsap, LLC_PDU_CMD);
59 llc_pdu_init_as_ui_cmd(skb);
60 rc = llc_mac_hdr_init(skb, sa: ev->saddr.mac, da: ev->daddr.mac);
61 if (likely(!rc)) {
62 skb_get(skb);
63 rc = dev_queue_xmit(skb);
64 }
65 return rc;
66}
67
68/**
69 * llc_sap_action_send_xid_c - send XID PDU as response to XID REQ
70 * @sap: SAP
71 * @skb: the event to send
72 *
73 * Send a XID command PDU to MAC layer in response to a XID REQUEST
74 * primitive from the network layer. Verify event is a primitive type
75 * event. Verify the primitive is a XID REQUEST.
76 */
77int llc_sap_action_send_xid_c(struct llc_sap *sap, struct sk_buff *skb)
78{
79 struct llc_sap_state_ev *ev = llc_sap_ev(skb);
80 int rc;
81
82 llc_pdu_header_init(skb, LLC_PDU_TYPE_U_XID, ssap: ev->saddr.lsap,
83 dsap: ev->daddr.lsap, LLC_PDU_CMD);
84 llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, rx_window: 0);
85 rc = llc_mac_hdr_init(skb, sa: ev->saddr.mac, da: ev->daddr.mac);
86 if (likely(!rc)) {
87 skb_get(skb);
88 rc = dev_queue_xmit(skb);
89 }
90 return rc;
91}
92
93/**
94 * llc_sap_action_send_xid_r - send XID PDU resp to MAC for received XID
95 * @sap: SAP
96 * @skb: the event to send
97 *
98 * Send XID response PDU to MAC in response to an earlier received XID
99 * command PDU. Verify event is a PDU type event
100 */
101int llc_sap_action_send_xid_r(struct llc_sap *sap, struct sk_buff *skb)
102{
103 u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
104 int rc = 1;
105 struct sk_buff *nskb;
106
107 llc_pdu_decode_sa(skb, sa: mac_da);
108 llc_pdu_decode_da(skb, da: mac_sa);
109 llc_pdu_decode_ssap(skb, ssap: &dsap);
110 nskb = llc_alloc_frame(NULL, dev: skb->dev, LLC_PDU_TYPE_U,
111 data_size: sizeof(struct llc_xid_info));
112 if (!nskb)
113 goto out;
114 llc_pdu_header_init(skb: nskb, LLC_PDU_TYPE_U, ssap: sap->laddr.lsap, dsap,
115 LLC_PDU_RSP);
116 llc_pdu_init_as_xid_rsp(skb: nskb, LLC_XID_NULL_CLASS_2, rx_window: 0);
117 rc = llc_mac_hdr_init(skb: nskb, sa: mac_sa, da: mac_da);
118 if (likely(!rc))
119 rc = dev_queue_xmit(skb: nskb);
120out:
121 return rc;
122}
123
124/**
125 * llc_sap_action_send_test_c - send TEST PDU to MAC in resp to TEST REQ
126 * @sap: SAP
127 * @skb: the event to send
128 *
129 * Send a TEST command PDU to the MAC layer in response to a TEST REQUEST
130 * primitive from the network layer. Verify event is a primitive type
131 * event; verify the primitive is a TEST REQUEST.
132 */
133int llc_sap_action_send_test_c(struct llc_sap *sap, struct sk_buff *skb)
134{
135 struct llc_sap_state_ev *ev = llc_sap_ev(skb);
136 int rc;
137
138 llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ssap: ev->saddr.lsap,
139 dsap: ev->daddr.lsap, LLC_PDU_CMD);
140 llc_pdu_init_as_test_cmd(skb);
141 rc = llc_mac_hdr_init(skb, sa: ev->saddr.mac, da: ev->daddr.mac);
142 if (likely(!rc)) {
143 skb_get(skb);
144 rc = dev_queue_xmit(skb);
145 }
146 return rc;
147}
148
149int llc_sap_action_send_test_r(struct llc_sap *sap, struct sk_buff *skb)
150{
151 u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
152 struct sk_buff *nskb;
153 int rc = 1;
154 u32 data_size;
155
156 llc_pdu_decode_sa(skb, sa: mac_da);
157 llc_pdu_decode_da(skb, da: mac_sa);
158 llc_pdu_decode_ssap(skb, ssap: &dsap);
159
160 /* The test request command is type U (llc_len = 3) */
161 data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
162 nskb = llc_alloc_frame(NULL, dev: skb->dev, LLC_PDU_TYPE_U, data_size);
163 if (!nskb)
164 goto out;
165 llc_pdu_header_init(skb: nskb, LLC_PDU_TYPE_U, ssap: sap->laddr.lsap, dsap,
166 LLC_PDU_RSP);
167 llc_pdu_init_as_test_rsp(skb: nskb, ev_skb: skb);
168 rc = llc_mac_hdr_init(skb: nskb, sa: mac_sa, da: mac_da);
169 if (likely(!rc))
170 rc = dev_queue_xmit(skb: nskb);
171out:
172 return rc;
173}
174
175/**
176 * llc_sap_action_report_status - report data link status to layer mgmt
177 * @sap: SAP
178 * @skb: the event to send
179 *
180 * Report data link status to layer management. Verify our event is the
181 * kind we expect.
182 */
183int llc_sap_action_report_status(struct llc_sap *sap, struct sk_buff *skb)
184{
185 return 0;
186}
187
188/**
189 * llc_sap_action_xid_ind - send XID PDU resp to net layer via XID IND
190 * @sap: SAP
191 * @skb: the event to send
192 *
193 * Send a XID response PDU to the network layer via a XID INDICATION
194 * primitive.
195 */
196int llc_sap_action_xid_ind(struct llc_sap *sap, struct sk_buff *skb)
197{
198 llc_sap_rtn_pdu(sap, skb);
199 return 0;
200}
201
202/**
203 * llc_sap_action_test_ind - send TEST PDU to net layer via TEST IND
204 * @sap: SAP
205 * @skb: the event to send
206 *
207 * Send a TEST response PDU to the network layer via a TEST INDICATION
208 * primitive. Verify our event is a PDU type event.
209 */
210int llc_sap_action_test_ind(struct llc_sap *sap, struct sk_buff *skb)
211{
212 llc_sap_rtn_pdu(sap, skb);
213 return 0;
214}
215

source code of linux/net/llc/llc_s_ac.c