xref: /linux/net/llc/llc_s_ac.c (revision 44f57d78)
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  */
37 int 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  */
52 int 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 		rc = dev_queue_xmit(skb);
63 	return rc;
64 }
65 
66 /**
67  *	llc_sap_action_send_xid_c - send XID PDU as response to XID REQ
68  *	@sap: SAP
69  *	@skb: the event to send
70  *
71  *	Send a XID command PDU to MAC layer in response to a XID REQUEST
72  *	primitive from the network layer. Verify event is a primitive type
73  *	event. Verify the primitive is a XID REQUEST.
74  */
75 int llc_sap_action_send_xid_c(struct llc_sap *sap, struct sk_buff *skb)
76 {
77 	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
78 	int rc;
79 
80 	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ev->saddr.lsap,
81 			    ev->daddr.lsap, LLC_PDU_CMD);
82 	llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, 0);
83 	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);
84 	if (likely(!rc))
85 		rc = dev_queue_xmit(skb);
86 	return rc;
87 }
88 
89 /**
90  *	llc_sap_action_send_xid_r - send XID PDU resp to MAC for received XID
91  *	@sap: SAP
92  *	@skb: the event to send
93  *
94  *	Send XID response PDU to MAC in response to an earlier received XID
95  *	command PDU. Verify event is a PDU type event
96  */
97 int llc_sap_action_send_xid_r(struct llc_sap *sap, struct sk_buff *skb)
98 {
99 	u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
100 	int rc = 1;
101 	struct sk_buff *nskb;
102 
103 	llc_pdu_decode_sa(skb, mac_da);
104 	llc_pdu_decode_da(skb, mac_sa);
105 	llc_pdu_decode_ssap(skb, &dsap);
106 	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
107 			       sizeof(struct llc_xid_info));
108 	if (!nskb)
109 		goto out;
110 	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
111 			    LLC_PDU_RSP);
112 	llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 0);
113 	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);
114 	if (likely(!rc))
115 		rc = dev_queue_xmit(nskb);
116 out:
117 	return rc;
118 }
119 
120 /**
121  *	llc_sap_action_send_test_c - send TEST PDU to MAC in resp to TEST REQ
122  *	@sap: SAP
123  *	@skb: the event to send
124  *
125  *	Send a TEST command PDU to the MAC layer in response to a TEST REQUEST
126  *	primitive from the network layer. Verify event is a primitive type
127  *	event; verify the primitive is a TEST REQUEST.
128  */
129 int llc_sap_action_send_test_c(struct llc_sap *sap, struct sk_buff *skb)
130 {
131 	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
132 	int rc;
133 
134 	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ev->saddr.lsap,
135 			    ev->daddr.lsap, LLC_PDU_CMD);
136 	llc_pdu_init_as_test_cmd(skb);
137 	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);
138 	if (likely(!rc))
139 		rc = dev_queue_xmit(skb);
140 	return rc;
141 }
142 
143 int llc_sap_action_send_test_r(struct llc_sap *sap, struct sk_buff *skb)
144 {
145 	u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
146 	struct sk_buff *nskb;
147 	int rc = 1;
148 	u32 data_size;
149 
150 	llc_pdu_decode_sa(skb, mac_da);
151 	llc_pdu_decode_da(skb, mac_sa);
152 	llc_pdu_decode_ssap(skb, &dsap);
153 
154 	/* The test request command is type U (llc_len = 3) */
155 	data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
156 	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);
157 	if (!nskb)
158 		goto out;
159 	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
160 			    LLC_PDU_RSP);
161 	llc_pdu_init_as_test_rsp(nskb, skb);
162 	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);
163 	if (likely(!rc))
164 		rc = dev_queue_xmit(nskb);
165 out:
166 	return rc;
167 }
168 
169 /**
170  *	llc_sap_action_report_status - report data link status to layer mgmt
171  *	@sap: SAP
172  *	@skb: the event to send
173  *
174  *	Report data link status to layer management. Verify our event is the
175  *	kind we expect.
176  */
177 int llc_sap_action_report_status(struct llc_sap *sap, struct sk_buff *skb)
178 {
179 	return 0;
180 }
181 
182 /**
183  *	llc_sap_action_xid_ind - send XID PDU resp to net layer via XID IND
184  *	@sap: SAP
185  *	@skb: the event to send
186  *
187  *	Send a XID response PDU to the network layer via a XID INDICATION
188  *	primitive.
189  */
190 int llc_sap_action_xid_ind(struct llc_sap *sap, struct sk_buff *skb)
191 {
192 	llc_sap_rtn_pdu(sap, skb);
193 	return 0;
194 }
195 
196 /**
197  *	llc_sap_action_test_ind - send TEST PDU to net layer via TEST IND
198  *	@sap: SAP
199  *	@skb: the event to send
200  *
201  *	Send a TEST response PDU to the network layer via a TEST INDICATION
202  *	primitive. Verify our event is a PDU type event.
203  */
204 int llc_sap_action_test_ind(struct llc_sap *sap, struct sk_buff *skb)
205 {
206 	llc_sap_rtn_pdu(sap, skb);
207 	return 0;
208 }
209