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1275 |
phoenix |
/*
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* AX.25 release 037
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*
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* This code REQUIRES 2.1.15 or higher/ NET3.038
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*
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* This module:
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* This module 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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* Most of this code is based on the SDL diagrams published in the 7th
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* ARRL Computer Networking Conference papers. The diagrams have mistakes
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* in them, but are mostly correct. Before you modify the code could you
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* read the SDL diagrams as the code is not obvious and probably very
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* easy to break;
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*
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* History
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* AX.25 036 Jonathan(G4KLX) Split from ax25_out.c.
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* AX.25 037 Jonathan(G4KLX) New timer architecture.
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*/
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/in.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/timer.h>
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#include <linux/string.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <net/ax25.h>
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#include <linux/inet.h>
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#include <linux/netdevice.h>
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#include <linux/skbuff.h>
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#include <net/sock.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <linux/fcntl.h>
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#include <linux/mm.h>
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#include <linux/interrupt.h>
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/*
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* The following routines are taken from page 170 of the 7th ARRL Computer
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* Networking Conference paper, as is the whole state machine.
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*/
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void ax25_std_nr_error_recovery(ax25_cb *ax25)
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{
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ax25_std_establish_data_link(ax25);
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}
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void ax25_std_establish_data_link(ax25_cb *ax25)
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{
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ax25->condition = 0x00;
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ax25->n2count = 0;
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if (ax25->modulus == AX25_MODULUS)
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ax25_send_control(ax25, AX25_SABM, AX25_POLLON, AX25_COMMAND);
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else
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ax25_send_control(ax25, AX25_SABME, AX25_POLLON, AX25_COMMAND);
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ax25_calculate_t1(ax25);
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ax25_stop_idletimer(ax25);
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ax25_stop_t3timer(ax25);
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ax25_stop_t2timer(ax25);
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ax25_start_t1timer(ax25);
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}
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void ax25_std_transmit_enquiry(ax25_cb *ax25)
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{
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if (ax25->condition & AX25_COND_OWN_RX_BUSY)
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ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_COMMAND);
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else
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ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_COMMAND);
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ax25->condition &= ~AX25_COND_ACK_PENDING;
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ax25_calculate_t1(ax25);
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ax25_start_t1timer(ax25);
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}
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void ax25_std_enquiry_response(ax25_cb *ax25)
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{
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if (ax25->condition & AX25_COND_OWN_RX_BUSY)
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ax25_send_control(ax25, AX25_RNR, AX25_POLLON, AX25_RESPONSE);
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else
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ax25_send_control(ax25, AX25_RR, AX25_POLLON, AX25_RESPONSE);
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ax25->condition &= ~AX25_COND_ACK_PENDING;
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}
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void ax25_std_timeout_response(ax25_cb *ax25)
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{
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if (ax25->condition & AX25_COND_OWN_RX_BUSY)
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ax25_send_control(ax25, AX25_RNR, AX25_POLLOFF, AX25_RESPONSE);
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else
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ax25_send_control(ax25, AX25_RR, AX25_POLLOFF, AX25_RESPONSE);
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ax25->condition &= ~AX25_COND_ACK_PENDING;
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}
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