/*
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/*
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* AX.25 release 037
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* AX.25 release 037
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*
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*
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* This code REQUIRES 2.1.15 or higher/ NET3.038
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* This code REQUIRES 2.1.15 or higher/ NET3.038
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*
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*
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* This module:
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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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* 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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* 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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* 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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* 2 of the License, or (at your option) any later version.
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*
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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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* 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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* 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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* 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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* read the SDL diagrams as the code is not obvious and probably very
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* easy to break;
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* easy to break;
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*
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*
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* History
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* History
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* AX.25 036 Jonathan(G4KLX) Cloned from ax25_out.c and ax25_subr.c.
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* AX.25 036 Jonathan(G4KLX) Cloned from ax25_out.c and ax25_subr.c.
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* Joerg(DL1BKE) Changed ax25_ds_enquiry_response(),
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* Joerg(DL1BKE) Changed ax25_ds_enquiry_response(),
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* fixed ax25_dama_on() and ax25_dama_off().
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* fixed ax25_dama_on() and ax25_dama_off().
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* AX.25 037 Jonathan(G4KLX) New timer architecture.
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* AX.25 037 Jonathan(G4KLX) New timer architecture.
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*/
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*/
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#include <linux/errno.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/socket.h>
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#include <linux/in.h>
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#include <linux/in.h>
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#include <linux/kernel.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/sched.h>
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#include <linux/timer.h>
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#include <linux/timer.h>
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#include <linux/string.h>
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#include <linux/string.h>
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#include <linux/sockios.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <linux/net.h>
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#include <net/ax25.h>
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#include <net/ax25.h>
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#include <linux/inet.h>
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#include <linux/inet.h>
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#include <linux/netdevice.h>
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#include <linux/netdevice.h>
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#include <linux/skbuff.h>
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#include <linux/skbuff.h>
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#include <net/sock.h>
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#include <net/sock.h>
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#include <asm/uaccess.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <asm/system.h>
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#include <linux/fcntl.h>
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#include <linux/fcntl.h>
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#include <linux/mm.h>
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#include <linux/mm.h>
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#include <linux/interrupt.h>
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#include <linux/interrupt.h>
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void ax25_ds_nr_error_recovery(ax25_cb *ax25)
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void ax25_ds_nr_error_recovery(ax25_cb *ax25)
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{
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{
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ax25_ds_establish_data_link(ax25);
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ax25_ds_establish_data_link(ax25);
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}
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}
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/*
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/*
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* dl1bke 960114: transmit I frames on DAMA poll
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* dl1bke 960114: transmit I frames on DAMA poll
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*/
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*/
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void ax25_ds_enquiry_response(ax25_cb *ax25)
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void ax25_ds_enquiry_response(ax25_cb *ax25)
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{
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{
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ax25_cb *ax25o;
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ax25_cb *ax25o;
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|
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/* Please note that neither DK4EG´s nor DG2FEF´s
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/* Please note that neither DK4EG´s nor DG2FEF´s
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* DAMA spec mention the following behaviour as seen
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* DAMA spec mention the following behaviour as seen
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* with TheFirmware:
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* with TheFirmware:
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*
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*
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* DB0ACH->DL1BKE <RR C P R0> [DAMA]
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* DB0ACH->DL1BKE <RR C P R0> [DAMA]
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* DL1BKE->DB0ACH <I NR=0 NS=0>
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* DL1BKE->DB0ACH <I NR=0 NS=0>
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* DL1BKE-7->DB0PRA-6 DB0ACH <I C S3 R5>
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* DL1BKE-7->DB0PRA-6 DB0ACH <I C S3 R5>
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* DL1BKE->DB0ACH <RR R F R0>
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* DL1BKE->DB0ACH <RR R F R0>
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*
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*
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* The Flexnet DAMA Master implementation apparently
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* The Flexnet DAMA Master implementation apparently
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* insists on the "proper" AX.25 behaviour:
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* insists on the "proper" AX.25 behaviour:
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*
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*
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* DB0ACH->DL1BKE <RR C P R0> [DAMA]
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* DB0ACH->DL1BKE <RR C P R0> [DAMA]
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* DL1BKE->DB0ACH <RR R F R0>
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* DL1BKE->DB0ACH <RR R F R0>
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* DL1BKE->DB0ACH <I NR=0 NS=0>
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* DL1BKE->DB0ACH <I NR=0 NS=0>
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* DL1BKE-7->DB0PRA-6 DB0ACH <I C S3 R5>
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* DL1BKE-7->DB0PRA-6 DB0ACH <I C S3 R5>
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*
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*
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* Flexnet refuses to send us *any* I frame if we send
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* Flexnet refuses to send us *any* I frame if we send
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* a REJ in case AX25_COND_REJECT is set. It is superfluous in
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* a REJ in case AX25_COND_REJECT is set. It is superfluous in
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* this mode anyway (a RR or RNR invokes the retransmission).
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* this mode anyway (a RR or RNR invokes the retransmission).
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* Is this a Flexnet bug?
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* Is this a Flexnet bug?
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*/
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*/
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ax25_std_enquiry_response(ax25);
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ax25_std_enquiry_response(ax25);
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if (!(ax25->condition & AX25_COND_PEER_RX_BUSY)) {
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if (!(ax25->condition & AX25_COND_PEER_RX_BUSY)) {
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ax25_requeue_frames(ax25);
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ax25_requeue_frames(ax25);
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ax25_kick(ax25);
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ax25_kick(ax25);
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}
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}
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if (ax25->state == AX25_STATE_1 || ax25->state == AX25_STATE_2 || skb_peek(&ax25->ack_queue) != NULL)
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if (ax25->state == AX25_STATE_1 || ax25->state == AX25_STATE_2 || skb_peek(&ax25->ack_queue) != NULL)
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ax25_ds_t1_timeout(ax25);
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ax25_ds_t1_timeout(ax25);
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else
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else
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ax25->n2count = 0;
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ax25->n2count = 0;
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ax25_start_t3timer(ax25);
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ax25_start_t3timer(ax25);
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ax25_ds_set_timer(ax25->ax25_dev);
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ax25_ds_set_timer(ax25->ax25_dev);
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for (ax25o = ax25_list; ax25o != NULL; ax25o = ax25o->next) {
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for (ax25o = ax25_list; ax25o != NULL; ax25o = ax25o->next) {
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if (ax25o == ax25)
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if (ax25o == ax25)
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continue;
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continue;
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if (ax25o->ax25_dev != ax25->ax25_dev)
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if (ax25o->ax25_dev != ax25->ax25_dev)
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continue;
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continue;
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if (ax25o->state == AX25_STATE_1 || ax25o->state == AX25_STATE_2) {
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if (ax25o->state == AX25_STATE_1 || ax25o->state == AX25_STATE_2) {
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ax25_ds_t1_timeout(ax25o);
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ax25_ds_t1_timeout(ax25o);
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continue;
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continue;
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}
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}
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if (!(ax25o->condition & AX25_COND_PEER_RX_BUSY) && ax25o->state == AX25_STATE_3) {
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if (!(ax25o->condition & AX25_COND_PEER_RX_BUSY) && ax25o->state == AX25_STATE_3) {
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ax25_requeue_frames(ax25o);
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ax25_requeue_frames(ax25o);
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ax25_kick(ax25o);
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ax25_kick(ax25o);
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}
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}
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if (ax25o->state == AX25_STATE_1 || ax25o->state == AX25_STATE_2 || skb_peek(&ax25o->ack_queue) != NULL)
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if (ax25o->state == AX25_STATE_1 || ax25o->state == AX25_STATE_2 || skb_peek(&ax25o->ack_queue) != NULL)
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ax25_ds_t1_timeout(ax25o);
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ax25_ds_t1_timeout(ax25o);
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/* do not start T3 for listening sockets (tnx DD8NE) */
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/* do not start T3 for listening sockets (tnx DD8NE) */
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if (ax25o->state != AX25_STATE_0)
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if (ax25o->state != AX25_STATE_0)
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ax25_start_t3timer(ax25o);
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ax25_start_t3timer(ax25o);
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}
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}
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}
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}
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void ax25_ds_establish_data_link(ax25_cb *ax25)
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void ax25_ds_establish_data_link(ax25_cb *ax25)
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{
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{
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ax25->condition &= AX25_COND_DAMA_MODE;
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ax25->condition &= AX25_COND_DAMA_MODE;
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ax25->n2count = 0;
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ax25->n2count = 0;
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ax25_calculate_t1(ax25);
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ax25_calculate_t1(ax25);
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ax25_start_t1timer(ax25);
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ax25_start_t1timer(ax25);
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ax25_stop_t2timer(ax25);
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ax25_stop_t2timer(ax25);
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ax25_start_t3timer(ax25);
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ax25_start_t3timer(ax25);
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}
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}
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/*
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/*
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* :::FIXME:::
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* :::FIXME:::
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* This is a kludge. Not all drivers recognize kiss commands.
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* This is a kludge. Not all drivers recognize kiss commands.
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* We need a driver level request to switch duplex mode, that does
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* We need a driver level request to switch duplex mode, that does
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* either SCC changing, PI config or KISS as required. Currently
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* either SCC changing, PI config or KISS as required. Currently
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* this request isn't reliable.
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* this request isn't reliable.
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*/
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*/
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static void ax25_kiss_cmd(ax25_dev *ax25_dev, unsigned char cmd, unsigned char param)
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static void ax25_kiss_cmd(ax25_dev *ax25_dev, unsigned char cmd, unsigned char param)
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{
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{
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struct sk_buff *skb;
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struct sk_buff *skb;
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unsigned char *p;
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unsigned char *p;
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if (ax25_dev->dev == NULL)
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if (ax25_dev->dev == NULL)
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return;
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return;
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if ((skb = alloc_skb(2, GFP_ATOMIC)) == NULL)
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if ((skb = alloc_skb(2, GFP_ATOMIC)) == NULL)
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return;
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return;
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skb->nh.raw = skb->data;
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skb->nh.raw = skb->data;
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p = skb_put(skb, 2);
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p = skb_put(skb, 2);
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*p++ = cmd;
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*p++ = cmd;
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*p++ = param;
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*p++ = param;
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skb->dev = ax25_dev->dev;
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skb->dev = ax25_dev->dev;
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skb->protocol = htons(ETH_P_AX25);
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skb->protocol = htons(ETH_P_AX25);
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dev_queue_xmit(skb);
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dev_queue_xmit(skb);
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}
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}
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/*
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/*
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* A nasty problem arises if we count the number of DAMA connections
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* A nasty problem arises if we count the number of DAMA connections
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* wrong, especially when connections on the device already existed
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* wrong, especially when connections on the device already existed
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* and our network node (or the sysop) decides to turn on DAMA Master
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* and our network node (or the sysop) decides to turn on DAMA Master
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* mode. We thus flag the 'real' slave connections with
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* mode. We thus flag the 'real' slave connections with
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* ax25->dama_slave=1 and look on every disconnect if still slave
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* ax25->dama_slave=1 and look on every disconnect if still slave
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* connections exist.
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* connections exist.
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*/
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*/
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static int ax25_check_dama_slave(ax25_dev *ax25_dev)
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static int ax25_check_dama_slave(ax25_dev *ax25_dev)
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{
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{
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ax25_cb *ax25;
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ax25_cb *ax25;
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for (ax25 = ax25_list; ax25 != NULL ; ax25 = ax25->next)
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for (ax25 = ax25_list; ax25 != NULL ; ax25 = ax25->next)
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if (ax25->ax25_dev == ax25_dev && (ax25->condition & AX25_COND_DAMA_MODE) && ax25->state > AX25_STATE_1)
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if (ax25->ax25_dev == ax25_dev && (ax25->condition & AX25_COND_DAMA_MODE) && ax25->state > AX25_STATE_1)
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return 1;
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return 1;
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return 0;
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return 0;
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}
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}
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void ax25_dev_dama_on(ax25_dev *ax25_dev)
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void ax25_dev_dama_on(ax25_dev *ax25_dev)
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{
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{
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if (ax25_dev == NULL)
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if (ax25_dev == NULL)
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return;
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return;
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if (ax25_dev->dama.slave == 0)
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if (ax25_dev->dama.slave == 0)
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ax25_kiss_cmd(ax25_dev, 5, 1);
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ax25_kiss_cmd(ax25_dev, 5, 1);
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|
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ax25_dev->dama.slave = 1;
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ax25_dev->dama.slave = 1;
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ax25_ds_set_timer(ax25_dev);
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ax25_ds_set_timer(ax25_dev);
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}
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}
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void ax25_dev_dama_off(ax25_dev *ax25_dev)
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void ax25_dev_dama_off(ax25_dev *ax25_dev)
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{
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{
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if (ax25_dev == NULL)
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if (ax25_dev == NULL)
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return;
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return;
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if (ax25_dev->dama.slave && !ax25_check_dama_slave(ax25_dev)) {
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if (ax25_dev->dama.slave && !ax25_check_dama_slave(ax25_dev)) {
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ax25_kiss_cmd(ax25_dev, 5, 0);
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ax25_kiss_cmd(ax25_dev, 5, 0);
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ax25_dev->dama.slave = 0;
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ax25_dev->dama.slave = 0;
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ax25_ds_del_timer(ax25_dev);
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ax25_ds_del_timer(ax25_dev);
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}
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}
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}
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}
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void ax25_dama_on(ax25_cb *ax25)
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void ax25_dama_on(ax25_cb *ax25)
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{
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{
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ax25_dev_dama_on(ax25->ax25_dev);
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ax25_dev_dama_on(ax25->ax25_dev);
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ax25->condition |= AX25_COND_DAMA_MODE;
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ax25->condition |= AX25_COND_DAMA_MODE;
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}
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}
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void ax25_dama_off(ax25_cb *ax25)
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void ax25_dama_off(ax25_cb *ax25)
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{
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{
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ax25->condition &= ~AX25_COND_DAMA_MODE;
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ax25->condition &= ~AX25_COND_DAMA_MODE;
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ax25_dev_dama_off(ax25->ax25_dev);
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ax25_dev_dama_off(ax25->ax25_dev);
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}
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}
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