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  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_unit_data_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, ev->saddr.lsap,
 58			    ev->daddr.lsap, LLC_PDU_CMD);
 59	llc_pdu_init_as_ui_cmd(skb);
 60	rc = llc_mac_hdr_init(skb, ev->saddr.mac, 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, ev->saddr.lsap,
 83			    ev->daddr.lsap, LLC_PDU_CMD);
 84	llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, 0);
 85	rc = llc_mac_hdr_init(skb, ev->saddr.mac, 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, mac_da);
108	llc_pdu_decode_da(skb, mac_sa);
109	llc_pdu_decode_ssap(skb, &dsap);
110	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
111			       sizeof(struct llc_xid_info));
112	if (!nskb)
113		goto out;
114	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
115			    LLC_PDU_RSP);
116	llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 0);
117	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);
118	if (likely(!rc))
119		rc = dev_queue_xmit(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, ev->saddr.lsap,
139			    ev->daddr.lsap, LLC_PDU_CMD);
140	llc_pdu_init_as_test_cmd(skb);
141	rc = llc_mac_hdr_init(skb, ev->saddr.mac, 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, mac_da);
157	llc_pdu_decode_da(skb, mac_sa);
158	llc_pdu_decode_ssap(skb, &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, skb->dev, LLC_PDU_TYPE_U, data_size);
163	if (!nskb)
164		goto out;
165	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
166			    LLC_PDU_RSP);
167	llc_pdu_init_as_test_rsp(nskb, skb);
168	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);
169	if (likely(!rc))
170		rc = dev_queue_xmit(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}