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1275 |
phoenix |
/*
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* NET An implementation of the IEEE 802.2 LLC protocol for the
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* LINUX operating system. LLC is implemented as a set of
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* state machines and callbacks for higher networking layers.
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*
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* Class 2 llc algorithm.
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* Pseudocode interpreter, transition table lookup,
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* data_request & indicate primitives...
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*
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* Code for initialization, termination, registration and
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* MAC layer glue.
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*
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* Copyright Tim Alpaerts,
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*
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Changes
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* Alan Cox : Chainsawed into Linux format
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* Modified to use llc_ names
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* Changed callbacks
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*
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* This file must be processed by sed before it can be compiled.
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*/
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#include
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#include
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#include
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#include
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#include
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#include
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#include
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#include
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#include
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#include "pseudo/pseudocode.h"
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#include "transit/pdutr.h"
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#include "transit/timertr.h"
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#include
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#include
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/*
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* Data_request() is called by the client to present a data unit
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* to the llc for transmission.
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* In the future this function should also check if the transmit window
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* allows the sending of another pdu, and if not put the skb on the atq
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* for deferred sending.
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*/
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int llc_data_request(llcptr lp, struct sk_buff *skb)
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| 54 |
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{
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if (skb_headroom(skb) < (lp->dev->hard_header_len +4)){
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printk("cl2llc: data_request() not enough headroom in skb\n");
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return -1;
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};
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skb_push(skb, 4);
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if ((lp->state != NORMAL) && (lp->state != BUSY) && (lp->state != REJECT))
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{
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printk("cl2llc: data_request() while no llc connection\n");
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return -1;
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}
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| 68 |
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if (lp->remote_busy)
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{ /* if the remote llc is BUSY, */
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| 70 |
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ADD_TO_ATQ(skb); /* save skb in the await transmit queue */
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return 0;
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}
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else
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{
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/*
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* Else proceed with xmit
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*/
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switch(lp->state)
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{
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case NORMAL:
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if(lp->p_flag)
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llc_interpret_pseudo_code(lp, NORMAL2, skb, NO_FRAME);
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else
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llc_interpret_pseudo_code(lp, NORMAL1, skb, NO_FRAME);
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break;
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case BUSY:
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if (lp->p_flag)
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llc_interpret_pseudo_code(lp, BUSY2, skb, NO_FRAME);
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else
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llc_interpret_pseudo_code(lp, BUSY1, skb, NO_FRAME);
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break;
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case REJECT:
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if (lp->p_flag)
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llc_interpret_pseudo_code(lp, REJECT2, skb, NO_FRAME);
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else
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llc_interpret_pseudo_code(lp, REJECT1, skb, NO_FRAME);
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break;
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default:;
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}
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if(lp->llc_callbacks)
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{
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lp->llc_event(lp);
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lp->llc_callbacks=0;
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}
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| 106 |
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return 0;
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}
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| 108 |
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}
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| 110 |
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| 111 |
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| 112 |
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/*
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* Disconnect_request() requests that the llc to terminate a connection
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*/
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| 116 |
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void disconnect_request(llcptr lp)
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{
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if ((lp->state == NORMAL) ||
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(lp->state == BUSY) ||
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(lp->state == REJECT) ||
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(lp->state == AWAIT) ||
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(lp->state == AWAIT_BUSY) ||
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(lp->state == AWAIT_REJECT))
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{
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lp->state = D_CONN;
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llc_interpret_pseudo_code(lp, SH1, NULL, NO_FRAME);
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if(lp->llc_callbacks)
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{
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lp->llc_event(lp);
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lp->llc_callbacks=0;
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}
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/*
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* lp may be invalid after the callback
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*/
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}
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}
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| 138 |
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| 139 |
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/*
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* Connect_request() requests that the llc to start a connection
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*/
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void connect_request(llcptr lp)
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{
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if (lp->state == ADM)
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{
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lp->state = SETUP;
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| 148 |
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llc_interpret_pseudo_code(lp, ADM1, NULL, NO_FRAME);
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if(lp->llc_callbacks)
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{
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| 151 |
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lp->llc_event(lp);
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lp->llc_callbacks=0;
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}
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/*
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* lp may be invalid after the callback
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*/
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}
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}
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| 159 |
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| 160 |
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| 161 |
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/*
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* Interpret_pseudo_code() executes the actions in the connection component
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* state transition table. Table 4 in document on p88.
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*
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* If this function is called to handle an incoming pdu, skb will point
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* to the buffer with the pdu and type will contain the decoded pdu type.
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*
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* If called by data_request skb points to an skb that was skb_alloc-ed by
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* the llc client to hold the information unit to be transmitted, there is
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* no valid type in this case.
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*
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* If called because a timer expired no skb is passed, and there is no
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* type.
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*/
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void llc_interpret_pseudo_code(llcptr lp, int pc_label, struct sk_buff *skb,
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char type)
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{
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short int pc; /* program counter in pseudo code array */
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| 180 |
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char p_flag_received;
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frameptr fr;
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| 182 |
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int resend_count; /* number of pdus resend by llc_resend_ipdu() */
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int ack_count; /* number of pdus acknowledged */
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| 184 |
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struct sk_buff *skb2;
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| 185 |
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| 186 |
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if (skb != NULL)
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{
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fr = (frameptr) skb->data;
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| 189 |
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}
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else
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fr = NULL;
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| 192 |
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| 193 |
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pc = pseudo_code_idx[pc_label];
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while(pseudo_code[pc])
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{
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switch(pseudo_code[pc])
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{
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| 198 |
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case IF_F=1_CLEAR_REMOTE_BUSY:
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if ((type != I_CMD) || (fr->i_hdr.i_pflag == 0))
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break;
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| 201 |
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case CLEAR_REMOTE_BUSY:
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lp->remote_busy = 0;
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llc_stop_timer(lp, BUSY_TIMER);
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| 204 |
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if ((lp->state == NORMAL) ||
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| 205 |
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(lp->state == REJECT) ||
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| 206 |
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(lp->state == BUSY))
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| 207 |
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{
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| 208 |
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skb2 = llc_pull_from_atq(lp);
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| 209 |
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if (skb2 != NULL)
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| 210 |
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llc_start_timer(lp, ACK_TIMER);
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| 211 |
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while (skb2 != NULL)
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| 212 |
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{
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| 213 |
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llc_sendipdu( lp, I_CMD, 0, skb2);
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| 214 |
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skb2 = llc_pull_from_atq(lp);
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| 215 |
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}
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| 216 |
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}
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| 217 |
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break;
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| 218 |
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case CONNECT_INDICATION:
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| 219 |
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lp->state = NORMAL; /* needed to eliminate connect_response() */
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| 220 |
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lp->llc_mode = MODE_ABM;
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| 221 |
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lp->llc_callbacks|=LLC_CONN_INDICATION;
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| 222 |
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break;
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| 223 |
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case CONNECT_CONFIRM:
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| 224 |
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lp->llc_mode = MODE_ABM;
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| 225 |
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lp->llc_callbacks|=LLC_CONN_CONFIRM;
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| 226 |
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break;
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| 227 |
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case DATA_INDICATION:
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| 228 |
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skb_pull(skb, 4);
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| 229 |
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lp->inc_skb=skb;
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| 230 |
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lp->llc_callbacks|=LLC_DATA_INDIC;
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| 231 |
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break;
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| 232 |
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case DISCONNECT_INDICATION:
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| 233 |
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lp->llc_mode = MODE_ADM;
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| 234 |
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lp->llc_callbacks|=LLC_DISC_INDICATION;
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| 235 |
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break;
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| 236 |
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case RESET_INDICATION(LOCAL):
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| 237 |
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lp->llc_callbacks|=LLC_RESET_INDIC_LOC;
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| 238 |
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break;
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| 239 |
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case RESET_INDICATION(REMOTE):
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| 240 |
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lp->llc_callbacks|=LLC_RESET_INDIC_REM;
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| 241 |
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break;
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| 242 |
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case RESET_CONFIRM:
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| 243 |
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lp->llc_callbacks|=LLC_RST_CONFIRM;
|
| 244 |
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break;
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| 245 |
|
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case REPORT_STATUS(FRMR_RECEIVED):
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| 246 |
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lp->llc_callbacks|=LLC_FRMR_RECV;
|
| 247 |
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break;
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| 248 |
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case REPORT_STATUS(FRMR_SENT):
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| 249 |
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lp->llc_callbacks|=LLC_FRMR_SENT;
|
| 250 |
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break;
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| 251 |
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case REPORT_STATUS(REMOTE_BUSY):
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| 252 |
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lp->llc_callbacks|=LLC_REMOTE_BUSY;
|
| 253 |
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break;
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| 254 |
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case REPORT_STATUS(REMOTE_NOT_BUSY):
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| 255 |
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lp->llc_callbacks|=LLC_REMOTE_NOTBUSY;
|
| 256 |
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break;
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| 257 |
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case SEND_DISC_CMD(P=X):
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| 258 |
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llc_sendpdu(lp, DISC_CMD, lp->f_flag, 0, NULL);
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| 259 |
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break;
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| 260 |
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case SEND_DM_RSP(F=X):
|
| 261 |
|
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llc_sendpdu(lp, DM_RSP, 0, 0, NULL);
|
| 262 |
|
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break;
|
| 263 |
|
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case SEND_FRMR_RSP(F=X):
|
| 264 |
|
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lp->frmr_info_fld.cntl1 = fr->pdu_cntl.byte1;
|
| 265 |
|
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lp->frmr_info_fld.cntl2 = fr->pdu_cntl.byte2;
|
| 266 |
|
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lp->frmr_info_fld.vs = lp->vs;
|
| 267 |
|
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lp->frmr_info_fld.vr_cr = lp->vr;
|
| 268 |
|
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llc_sendpdu(lp, FRMR_RSP, 0, 5, (char *) &lp->frmr_info_fld);
|
| 269 |
|
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break;
|
| 270 |
|
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case RE-SEND_FRMR_RSP(F=0):
|
| 271 |
|
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llc_sendpdu(lp, FRMR_RSP, 0, 5, (char *) &lp->frmr_info_fld);
|
| 272 |
|
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break;
|
| 273 |
|
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case RE-SEND_FRMR_RSP(F=P):
|
| 274 |
|
|
llc_sendpdu(lp, FRMR_RSP, lp->p_flag,
|
| 275 |
|
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5, (char *) &lp->frmr_info_fld);
|
| 276 |
|
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break;
|
| 277 |
|
|
case SEND_I_CMD(P=1):
|
| 278 |
|
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llc_sendipdu(lp, I_CMD, 1, skb);
|
| 279 |
|
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break;
|
| 280 |
|
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case RE-SEND_I_CMD(P=1):
|
| 281 |
|
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resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 1);
|
| 282 |
|
|
break;
|
| 283 |
|
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case RE-SEND_I_CMD(P=1)_OR_SEND_RR:
|
| 284 |
|
|
resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 1);
|
| 285 |
|
|
if (resend_count == 0)
|
| 286 |
|
|
{
|
| 287 |
|
|
llc_sendpdu(lp, RR_CMD, 1, 0, NULL);
|
| 288 |
|
|
}
|
| 289 |
|
|
break;
|
| 290 |
|
|
case SEND_I_XXX(X=0):
|
| 291 |
|
|
llc_sendipdu(lp, I_CMD, 0, skb);
|
| 292 |
|
|
break;
|
| 293 |
|
|
case RE-SEND_I_XXX(X=0):
|
| 294 |
|
|
resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 0);
|
| 295 |
|
|
break;
|
| 296 |
|
|
case RE-SEND_I_XXX(X=0)_OR_SEND_RR:
|
| 297 |
|
|
resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_CMD, 0);
|
| 298 |
|
|
if (resend_count == 0)
|
| 299 |
|
|
{
|
| 300 |
|
|
llc_sendpdu(lp, RR_CMD, 0, 0, NULL);
|
| 301 |
|
|
}
|
| 302 |
|
|
break;
|
| 303 |
|
|
case RE-SEND_I_RSP(F=1):
|
| 304 |
|
|
resend_count = llc_resend_ipdu(lp, fr->i_hdr.nr, I_RSP, 1);
|
| 305 |
|
|
break;
|
| 306 |
|
|
case SEND_REJ_CMD(P=1):
|
| 307 |
|
|
llc_sendpdu(lp, REJ_CMD, 1, 0, NULL);
|
| 308 |
|
|
break;
|
| 309 |
|
|
case SEND_REJ_RSP(F=1):
|
| 310 |
|
|
llc_sendpdu(lp, REJ_RSP, 1, 0, NULL);
|
| 311 |
|
|
break;
|
| 312 |
|
|
case SEND_REJ_XXX(X=0):
|
| 313 |
|
|
if (IS_RSP(fr))
|
| 314 |
|
|
llc_sendpdu(lp, REJ_CMD, 0, 0, NULL);
|
| 315 |
|
|
else
|
| 316 |
|
|
llc_sendpdu(lp, REJ_RSP, 0, 0, NULL);
|
| 317 |
|
|
break;
|
| 318 |
|
|
case SEND_RNR_CMD(F=1):
|
| 319 |
|
|
llc_sendpdu(lp, RNR_CMD, 1, 0, NULL);
|
| 320 |
|
|
break;
|
| 321 |
|
|
case SEND_RNR_RSP(F=1):
|
| 322 |
|
|
llc_sendpdu(lp, RNR_RSP, 1, 0, NULL);
|
| 323 |
|
|
break;
|
| 324 |
|
|
case SEND_RNR_XXX(X=0):
|
| 325 |
|
|
if (IS_RSP(fr))
|
| 326 |
|
|
llc_sendpdu(lp, RNR_CMD, 0, 0, NULL);
|
| 327 |
|
|
else
|
| 328 |
|
|
llc_sendpdu(lp, RNR_RSP, 0, 0, NULL);
|
| 329 |
|
|
break;
|
| 330 |
|
|
case SET_REMOTE_BUSY:
|
| 331 |
|
|
if (lp->remote_busy == 0)
|
| 332 |
|
|
{
|
| 333 |
|
|
lp->remote_busy = 1;
|
| 334 |
|
|
llc_start_timer(lp, BUSY_TIMER);
|
| 335 |
|
|
lp->llc_callbacks|=LLC_REMOTE_BUSY;
|
| 336 |
|
|
}
|
| 337 |
|
|
else if (lp->timer_state[BUSY_TIMER] == TIMER_IDLE)
|
| 338 |
|
|
{
|
| 339 |
|
|
llc_start_timer(lp, BUSY_TIMER);
|
| 340 |
|
|
}
|
| 341 |
|
|
break;
|
| 342 |
|
|
case OPTIONAL_SEND_RNR_XXX(X=0):
|
| 343 |
|
|
if (IS_RSP(fr))
|
| 344 |
|
|
llc_sendpdu(lp, RNR_CMD, 0, 0, NULL);
|
| 345 |
|
|
else
|
| 346 |
|
|
llc_sendpdu(lp, RNR_RSP, 0, 0, NULL);
|
| 347 |
|
|
break;
|
| 348 |
|
|
case SEND_RR_CMD(P=1):
|
| 349 |
|
|
llc_sendpdu(lp, RR_CMD, 1, 0, NULL);
|
| 350 |
|
|
break;
|
| 351 |
|
|
case SEND_ACKNOWLEDGE_CMD(P=1):
|
| 352 |
|
|
llc_sendpdu(lp, RR_CMD, 1, 0, NULL);
|
| 353 |
|
|
break;
|
| 354 |
|
|
case SEND_RR_RSP(F=1):
|
| 355 |
|
|
llc_sendpdu(lp, RR_RSP, 1, 0, NULL);
|
| 356 |
|
|
break;
|
| 357 |
|
|
case SEND_ACKNOWLEDGE_RSP(F=1):
|
| 358 |
|
|
llc_sendpdu(lp, RR_RSP, 1, 0, NULL);
|
| 359 |
|
|
break;
|
| 360 |
|
|
case SEND_RR_XXX(X=0):
|
| 361 |
|
|
llc_sendpdu(lp, RR_RSP, 0, 0, NULL);
|
| 362 |
|
|
break;
|
| 363 |
|
|
case SEND_ACKNOWLEDGE_XXX(X=0):
|
| 364 |
|
|
if (IS_RSP(fr))
|
| 365 |
|
|
llc_sendpdu(lp, RR_CMD, 0, 0, NULL);
|
| 366 |
|
|
else
|
| 367 |
|
|
llc_sendpdu(lp, RR_RSP, 0, 0, NULL);
|
| 368 |
|
|
break;
|
| 369 |
|
|
case SEND_SABME_CMD(P=X):
|
| 370 |
|
|
llc_sendpdu(lp, SABME_CMD, 0, 0, NULL);
|
| 371 |
|
|
lp->f_flag = 0;
|
| 372 |
|
|
break;
|
| 373 |
|
|
case SEND_UA_RSP(F=X):
|
| 374 |
|
|
llc_sendpdu(lp, UA_RSP, lp->f_flag, 0, NULL);
|
| 375 |
|
|
break;
|
| 376 |
|
|
case S_FLAG:=0:
|
| 377 |
|
|
lp->s_flag = 0;
|
| 378 |
|
|
break;
|
| 379 |
|
|
case S_FLAG:=1:
|
| 380 |
|
|
lp->s_flag = 1;
|
| 381 |
|
|
break;
|
| 382 |
|
|
case START_P_TIMER:
|
| 383 |
|
|
if(lp->timer_state[P_TIMER] == TIMER_RUNNING)
|
| 384 |
|
|
llc_stop_timer(lp, P_TIMER);
|
| 385 |
|
|
llc_start_timer(lp, P_TIMER);
|
| 386 |
|
|
if (lp->p_flag == 0)
|
| 387 |
|
|
{
|
| 388 |
|
|
lp->retry_count = 0;
|
| 389 |
|
|
lp->p_flag = 1;
|
| 390 |
|
|
}
|
| 391 |
|
|
break;
|
| 392 |
|
|
case START_ACK_TIMER_IF_NOT_RUNNING:
|
| 393 |
|
|
if (lp->timer_state[ACK_TIMER] == TIMER_IDLE)
|
| 394 |
|
|
llc_start_timer(lp, ACK_TIMER);
|
| 395 |
|
|
break;
|
| 396 |
|
|
case START_ACK_TIMER:
|
| 397 |
|
|
llc_start_timer(lp, ACK_TIMER);
|
| 398 |
|
|
break;
|
| 399 |
|
|
case START_REJ_TIMER:
|
| 400 |
|
|
llc_start_timer(lp, REJ_TIMER);
|
| 401 |
|
|
break;
|
| 402 |
|
|
case STOP_ACK_TIMER:
|
| 403 |
|
|
llc_stop_timer(lp, ACK_TIMER);
|
| 404 |
|
|
break;
|
| 405 |
|
|
case STOP_P_TIMER:
|
| 406 |
|
|
llc_stop_timer(lp, ACK_TIMER);
|
| 407 |
|
|
lp->p_flag = 0;
|
| 408 |
|
|
break;
|
| 409 |
|
|
case IF_DATA_FLAG=2_STOP_REJ_TIMER:
|
| 410 |
|
|
if (lp->data_flag == 2)
|
| 411 |
|
|
llc_stop_timer(lp, REJ_TIMER);
|
| 412 |
|
|
break;
|
| 413 |
|
|
case STOP_REJ_TIMER:
|
| 414 |
|
|
llc_stop_timer(lp, REJ_TIMER);
|
| 415 |
|
|
break;
|
| 416 |
|
|
case STOP_ALL_TIMERS:
|
| 417 |
|
|
llc_stop_timer(lp, ACK_TIMER);
|
| 418 |
|
|
llc_stop_timer(lp, P_TIMER);
|
| 419 |
|
|
llc_stop_timer(lp, REJ_TIMER);
|
| 420 |
|
|
llc_stop_timer(lp, BUSY_TIMER);
|
| 421 |
|
|
break;
|
| 422 |
|
|
case STOP_OTHER_TIMERS:
|
| 423 |
|
|
llc_stop_timer(lp, P_TIMER);
|
| 424 |
|
|
llc_stop_timer(lp, REJ_TIMER);
|
| 425 |
|
|
llc_stop_timer(lp, BUSY_TIMER);
|
| 426 |
|
|
break;
|
| 427 |
|
|
case UPDATE_N(R)_RECEIVED:
|
| 428 |
|
|
ack_count = llc_free_acknowledged_skbs(lp,
|
| 429 |
|
|
(unsigned char) fr->s_hdr.nr);
|
| 430 |
|
|
if (ack_count > 0)
|
| 431 |
|
|
{
|
| 432 |
|
|
lp->retry_count = 0;
|
| 433 |
|
|
llc_stop_timer(lp, ACK_TIMER);
|
| 434 |
|
|
if (skb_peek(&lp->rtq) != NULL)
|
| 435 |
|
|
{
|
| 436 |
|
|
/*
|
| 437 |
|
|
* Re-transmit queue not empty
|
| 438 |
|
|
*/
|
| 439 |
|
|
llc_start_timer(lp, ACK_TIMER);
|
| 440 |
|
|
}
|
| 441 |
|
|
}
|
| 442 |
|
|
break;
|
| 443 |
|
|
case UPDATE_P_FLAG:
|
| 444 |
|
|
if (IS_UFRAME(fr))
|
| 445 |
|
|
p_flag_received = fr->u_hdr.u_pflag;
|
| 446 |
|
|
else
|
| 447 |
|
|
p_flag_received = fr->i_hdr.i_pflag;
|
| 448 |
|
|
if ((fr->pdu_hdr.ssap & 0x01) && (p_flag_received))
|
| 449 |
|
|
{
|
| 450 |
|
|
lp->p_flag = 0;
|
| 451 |
|
|
llc_stop_timer(lp, P_TIMER);
|
| 452 |
|
|
}
|
| 453 |
|
|
break;
|
| 454 |
|
|
case DATA_FLAG:=2:
|
| 455 |
|
|
lp->data_flag = 2;
|
| 456 |
|
|
break;
|
| 457 |
|
|
case DATA_FLAG:=0:
|
| 458 |
|
|
lp->data_flag = 0;
|
| 459 |
|
|
break;
|
| 460 |
|
|
case DATA_FLAG:=1:
|
| 461 |
|
|
lp->data_flag = 1;
|
| 462 |
|
|
break;
|
| 463 |
|
|
case IF_DATA_FLAG_=0_THEN_DATA_FLAG:=1:
|
| 464 |
|
|
if (lp->data_flag == 0)
|
| 465 |
|
|
lp->data_flag = 1;
|
| 466 |
|
|
break;
|
| 467 |
|
|
case P_FLAG:=0:
|
| 468 |
|
|
lp->p_flag = 0;
|
| 469 |
|
|
break;
|
| 470 |
|
|
case P_FLAG:=P:
|
| 471 |
|
|
lp->p_flag = lp->f_flag;
|
| 472 |
|
|
break;
|
| 473 |
|
|
case REMOTE_BUSY:=0:
|
| 474 |
|
|
lp->remote_busy = 0;
|
| 475 |
|
|
break;
|
| 476 |
|
|
case RETRY_COUNT:=0:
|
| 477 |
|
|
lp->retry_count = 0;
|
| 478 |
|
|
break;
|
| 479 |
|
|
case RETRY_COUNT:=RETRY_COUNT+1:
|
| 480 |
|
|
lp->retry_count++;
|
| 481 |
|
|
break;
|
| 482 |
|
|
case V(R):=0:
|
| 483 |
|
|
lp->vr = 0;
|
| 484 |
|
|
break;
|
| 485 |
|
|
case V(R):=V(R)+1:
|
| 486 |
|
|
lp->vr++;
|
| 487 |
|
|
break;
|
| 488 |
|
|
case V(S):=0:
|
| 489 |
|
|
lp->vs = 0;
|
| 490 |
|
|
break;
|
| 491 |
|
|
case V(S):=N(R):
|
| 492 |
|
|
lp->vs = fr->i_hdr.nr;
|
| 493 |
|
|
break;
|
| 494 |
|
|
case F_FLAG:=P:
|
| 495 |
|
|
if (IS_UFRAME(fr))
|
| 496 |
|
|
lp->f_flag = fr->u_hdr.u_pflag;
|
| 497 |
|
|
else
|
| 498 |
|
|
lp->f_flag = fr->i_hdr.i_pflag;
|
| 499 |
|
|
break;
|
| 500 |
|
|
default:;
|
| 501 |
|
|
}
|
| 502 |
|
|
pc++;
|
| 503 |
|
|
}
|
| 504 |
|
|
}
|
| 505 |
|
|
|
| 506 |
|
|
|
| 507 |
|
|
/*
|
| 508 |
|
|
* Process_otype2_frame will handle incoming frames
|
| 509 |
|
|
* for 802.2 Type 2 Procedure.
|
| 510 |
|
|
*/
|
| 511 |
|
|
|
| 512 |
|
|
void llc_process_otype2_frame(llcptr lp, struct sk_buff *skb, char type)
|
| 513 |
|
|
{
|
| 514 |
|
|
int idx; /* index in transition table */
|
| 515 |
|
|
int pc_label; /* action to perform, from tr tbl */
|
| 516 |
|
|
int validation; /* result of validate_seq_nos */
|
| 517 |
|
|
int p_flag_received; /* p_flag in received frame */
|
| 518 |
|
|
frameptr fr;
|
| 519 |
|
|
|
| 520 |
|
|
fr = (frameptr) skb->data;
|
| 521 |
|
|
|
| 522 |
|
|
if (IS_UFRAME(fr))
|
| 523 |
|
|
p_flag_received = fr->u_hdr.u_pflag;
|
| 524 |
|
|
else
|
| 525 |
|
|
p_flag_received = fr->i_hdr.i_pflag;
|
| 526 |
|
|
|
| 527 |
|
|
switch(lp->state)
|
| 528 |
|
|
{
|
| 529 |
|
|
/* Compute index in transition table: */
|
| 530 |
|
|
case ADM:
|
| 531 |
|
|
idx = type;
|
| 532 |
|
|
idx = (idx << 1) + p_flag_received;
|
| 533 |
|
|
break;
|
| 534 |
|
|
case CONN:
|
| 535 |
|
|
case RESET_WAIT:
|
| 536 |
|
|
case RESET_CHECK:
|
| 537 |
|
|
case ERROR:
|
| 538 |
|
|
idx = type;
|
| 539 |
|
|
break;
|
| 540 |
|
|
case SETUP:
|
| 541 |
|
|
case RESET:
|
| 542 |
|
|
case D_CONN:
|
| 543 |
|
|
idx = type;
|
| 544 |
|
|
idx = (idx << 1) + lp->p_flag;
|
| 545 |
|
|
break;
|
| 546 |
|
|
case NORMAL:
|
| 547 |
|
|
case BUSY:
|
| 548 |
|
|
case REJECT:
|
| 549 |
|
|
case AWAIT:
|
| 550 |
|
|
case AWAIT_BUSY:
|
| 551 |
|
|
case AWAIT_REJECT:
|
| 552 |
|
|
validation = llc_validate_seq_nos(lp, fr);
|
| 553 |
|
|
if (validation > 3)
|
| 554 |
|
|
type = BAD_FRAME;
|
| 555 |
|
|
idx = type;
|
| 556 |
|
|
idx = (idx << 1);
|
| 557 |
|
|
if (validation & 1)
|
| 558 |
|
|
idx = idx +1;
|
| 559 |
|
|
idx = (idx << 1) + p_flag_received;
|
| 560 |
|
|
idx = (idx << 1) + lp->p_flag;
|
| 561 |
|
|
default:
|
| 562 |
|
|
printk("llc_proc: bad state\n");
|
| 563 |
|
|
return;
|
| 564 |
|
|
}
|
| 565 |
|
|
idx = (idx << 1) + pdutr_offset[lp->state];
|
| 566 |
|
|
lp->state = pdutr_entry[idx +1];
|
| 567 |
|
|
pc_label = pdutr_entry[idx];
|
| 568 |
|
|
if (pc_label != NOP)
|
| 569 |
|
|
{
|
| 570 |
|
|
llc_interpret_pseudo_code(lp, pc_label, skb, type);
|
| 571 |
|
|
if(lp->llc_callbacks)
|
| 572 |
|
|
{
|
| 573 |
|
|
lp->llc_event(lp);
|
| 574 |
|
|
lp->llc_callbacks=0;
|
| 575 |
|
|
}
|
| 576 |
|
|
/*
|
| 577 |
|
|
* lp may no longer be valid after this point. Be
|
| 578 |
|
|
* careful what is added!
|
| 579 |
|
|
*/
|
| 580 |
|
|
}
|
| 581 |
|
|
}
|
| 582 |
|
|
|
| 583 |
|
|
|
| 584 |
|
|
void llc_timer_expired(llcptr lp, int t)
|
| 585 |
|
|
{
|
| 586 |
|
|
int idx; /* index in transition table */
|
| 587 |
|
|
int pc_label; /* action to perform, from tr tbl */
|
| 588 |
|
|
|
| 589 |
|
|
lp->timer_state[t] = TIMER_EXPIRED;
|
| 590 |
|
|
idx = lp->state; /* Compute index in transition table: */
|
| 591 |
|
|
idx = (idx << 2) + t;
|
| 592 |
|
|
idx = idx << 1;
|
| 593 |
|
|
if (lp->retry_count >= lp->n2)
|
| 594 |
|
|
idx = idx + 1;
|
| 595 |
|
|
idx = (idx << 1) + lp->s_flag;
|
| 596 |
|
|
idx = (idx << 1) + lp->p_flag;
|
| 597 |
|
|
idx = idx << 1; /* 2 bytes per entry: action & newstate */
|
| 598 |
|
|
|
| 599 |
|
|
pc_label = timertr_entry[idx];
|
| 600 |
|
|
if (pc_label != NOP)
|
| 601 |
|
|
{
|
| 602 |
|
|
llc_interpret_pseudo_code(lp, pc_label, NULL, NO_FRAME);
|
| 603 |
|
|
lp->state = timertr_entry[idx +1];
|
| 604 |
|
|
}
|
| 605 |
|
|
lp->timer_state[t] = TIMER_IDLE;
|
| 606 |
|
|
if(lp->llc_callbacks)
|
| 607 |
|
|
{
|
| 608 |
|
|
lp->llc_event(lp);
|
| 609 |
|
|
lp->llc_callbacks=0;
|
| 610 |
|
|
}
|
| 611 |
|
|
/*
|
| 612 |
|
|
* And lp may have vanished in the event callback
|
| 613 |
|
|
*/
|
| 614 |
|
|
}
|
| 615 |
|
|
|
