net/llc/llc_s_ac.c

   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                 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  */
  77 int 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  */
 101 int 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);
 120 out:
 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  */
 133 int 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
 149 int 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);
 171 out:
 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  */
 183 int 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  */
 196 int 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  */
 210 int 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 }