/*
   * llc_s_ac.c - actions performed during sap state transition.
   *
   * Description :
   *   Functions in this module are implementation of sap component actions.
   *   Details of actions can be found in IEEE-802.2 standard document.
   *   All functions have one sap and one event as input argument. All of
   *   them return 0 On success and 1 otherwise.
   *
   * Copyright (c) 1997 by Procom Technology, Inc.
   *		 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   *
   * This program can be redistributed or modified under the terms of the
   * GNU General Public License as published by the Free Software Foundation.
   * This program is distributed without any warranty or implied warranty
   * of merchantability or fitness for a particular purpose.
   *
   * See the GNU General Public License for more details.
   */
  
  #include <linux/netdevice.h>
  #include <net/llc.h>
  #include <net/llc_pdu.h>
  #include <net/llc_s_ac.h>
  #include <net/llc_s_ev.h>
  #include <net/llc_sap.h>

  
  /**
   *	llc_sap_action_unit_data_ind - forward UI PDU to network layer
   *	@sap: SAP
   *	@skb: the event to forward
   *
   *	Received a UI PDU from MAC layer; forward to network layer as a
   *	UNITDATA INDICATION; verify our event is the kind we expect
   */
  int llc_sap_action_unitdata_ind(struct llc_sap *sap, struct sk_buff *skb)
  {
  	llc_sap_rtn_pdu(sap, skb);
  	return 0;
  }
  
  /**
   *	llc_sap_action_send_ui - sends UI PDU resp to UNITDATA REQ to MAC layer
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Sends a UI PDU to the MAC layer in response to a UNITDATA REQUEST
   *	primitive from the network layer. Verifies event is a primitive type of
   *	event. Verify the primitive is a UNITDATA REQUEST.
   */
  int llc_sap_action_send_ui(struct llc_sap *sap, struct sk_buff *skb)
  {
  	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
  	int rc;
  
  	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ev->saddr.lsap,
  			    ev->daddr.lsap, LLC_PDU_CMD);
  	llc_pdu_init_as_ui_cmd(skb);
  	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);

  	if (likely(!rc)) {
  		skb_get(skb);

  		rc = dev_queue_xmit(skb);

  	}

  	return rc;
  }
  
  /**
   *	llc_sap_action_send_xid_c - send XID PDU as response to XID REQ
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Send a XID command PDU to MAC layer in response to a XID REQUEST
   *	primitive from the network layer. Verify event is a primitive type
   *	event. Verify the primitive is a XID REQUEST.
   */
  int llc_sap_action_send_xid_c(struct llc_sap *sap, struct sk_buff *skb)
  {
  	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
  	int rc;
  
  	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ev->saddr.lsap,
  			    ev->daddr.lsap, LLC_PDU_CMD);
  	llc_pdu_init_as_xid_cmd(skb, LLC_XID_NULL_CLASS_2, 0);
  	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);

  	if (likely(!rc)) {
  		skb_get(skb);

  		rc = dev_queue_xmit(skb);

  	}

  	return rc;
  }
  
  /**
   *	llc_sap_action_send_xid_r - send XID PDU resp to MAC for received XID
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Send XID response PDU to MAC in response to an earlier received XID
   *	command PDU. Verify event is a PDU type event
   */
  int llc_sap_action_send_xid_r(struct llc_sap *sap, struct sk_buff *skb)
  {
  	u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
  	int rc = 1;
  	struct sk_buff *nskb;
  
  	llc_pdu_decode_sa(skb, mac_da);
  	llc_pdu_decode_da(skb, mac_sa);
  	llc_pdu_decode_ssap(skb, &dsap);

  	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
  			       sizeof(struct llc_xid_info));

  	if (!nskb)
  		goto out;

  	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
  			    LLC_PDU_RSP);
  	llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 0);
  	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);

  	if (likely(!rc))

  		rc = dev_queue_xmit(nskb);
  out:
  	return rc;
  }
  
  /**
   *	llc_sap_action_send_test_c - send TEST PDU to MAC in resp to TEST REQ
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Send a TEST command PDU to the MAC layer in response to a TEST REQUEST
   *	primitive from the network layer. Verify event is a primitive type
   *	event; verify the primitive is a TEST REQUEST.
   */
  int llc_sap_action_send_test_c(struct llc_sap *sap, struct sk_buff *skb)
  {
  	struct llc_sap_state_ev *ev = llc_sap_ev(skb);
  	int rc;
  
  	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, ev->saddr.lsap,
  			    ev->daddr.lsap, LLC_PDU_CMD);
  	llc_pdu_init_as_test_cmd(skb);
  	rc = llc_mac_hdr_init(skb, ev->saddr.mac, ev->daddr.mac);

  	if (likely(!rc)) {
  		skb_get(skb);

  		rc = dev_queue_xmit(skb);

  	}

  	return rc;
  }
  
  int llc_sap_action_send_test_r(struct llc_sap *sap, struct sk_buff *skb)
  {
  	u8 mac_da[ETH_ALEN], mac_sa[ETH_ALEN], dsap;
  	struct sk_buff *nskb;
  	int rc = 1;

  	u32 data_size;

  
  	llc_pdu_decode_sa(skb, mac_da);
  	llc_pdu_decode_da(skb, mac_sa);
  	llc_pdu_decode_ssap(skb, &dsap);

  
  	/* The test request command is type U (llc_len = 3) */
  	data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
  	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);

  	if (!nskb)
  		goto out;

  	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap, dsap,
  			    LLC_PDU_RSP);
  	llc_pdu_init_as_test_rsp(nskb, skb);
  	rc = llc_mac_hdr_init(nskb, mac_sa, mac_da);

  	if (likely(!rc))

  		rc = dev_queue_xmit(nskb);
  out:
  	return rc;
  }
  
  /**
   *	llc_sap_action_report_status - report data link status to layer mgmt
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Report data link status to layer management. Verify our event is the
   *	kind we expect.
   */
  int llc_sap_action_report_status(struct llc_sap *sap, struct sk_buff *skb)
  {
  	return 0;
  }
  
  /**
   *	llc_sap_action_xid_ind - send XID PDU resp to net layer via XID IND
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Send a XID response PDU to the network layer via a XID INDICATION
   *	primitive.
   */
  int llc_sap_action_xid_ind(struct llc_sap *sap, struct sk_buff *skb)
  {
  	llc_sap_rtn_pdu(sap, skb);
  	return 0;
  }
  
  /**
   *	llc_sap_action_test_ind - send TEST PDU to net layer via TEST IND
   *	@sap: SAP
   *	@skb: the event to send
   *
   *	Send a TEST response PDU to the network layer via a TEST INDICATION
   *	primitive. Verify our event is a PDU type event.
   */
  int llc_sap_action_test_ind(struct llc_sap *sap, struct sk_buff *skb)
  {
  	llc_sap_rtn_pdu(sap, skb);
  	return 0;
  }