/net/rose/rose_link.c
C | 291 lines | 202 code | 58 blank | 31 comment | 29 complexity | c76d7a9609ef6204cb63f7208b193d30 MD5 | raw file
- /*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
- */
- #include <linux/errno.h>
- #include <linux/types.h>
- #include <linux/socket.h>
- #include <linux/in.h>
- #include <linux/kernel.h>
- #include <linux/jiffies.h>
- #include <linux/timer.h>
- #include <linux/string.h>
- #include <linux/sockios.h>
- #include <linux/net.h>
- #include <linux/slab.h>
- #include <net/ax25.h>
- #include <linux/inet.h>
- #include <linux/netdevice.h>
- #include <linux/skbuff.h>
- #include <net/sock.h>
- #include <linux/fcntl.h>
- #include <linux/mm.h>
- #include <linux/interrupt.h>
- #include <linux/netfilter.h>
- #include <net/rose.h>
- static void rose_ftimer_expiry(unsigned long);
- static void rose_t0timer_expiry(unsigned long);
- static void rose_transmit_restart_confirmation(struct rose_neigh *neigh);
- static void rose_transmit_restart_request(struct rose_neigh *neigh);
- void rose_start_ftimer(struct rose_neigh *neigh)
- {
- del_timer(&neigh->ftimer);
- neigh->ftimer.data = (unsigned long)neigh;
- neigh->ftimer.function = &rose_ftimer_expiry;
- neigh->ftimer.expires =
- jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);
- add_timer(&neigh->ftimer);
- }
- static void rose_start_t0timer(struct rose_neigh *neigh)
- {
- del_timer(&neigh->t0timer);
- neigh->t0timer.data = (unsigned long)neigh;
- neigh->t0timer.function = &rose_t0timer_expiry;
- neigh->t0timer.expires =
- jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);
- add_timer(&neigh->t0timer);
- }
- void rose_stop_ftimer(struct rose_neigh *neigh)
- {
- del_timer(&neigh->ftimer);
- }
- void rose_stop_t0timer(struct rose_neigh *neigh)
- {
- del_timer(&neigh->t0timer);
- }
- int rose_ftimer_running(struct rose_neigh *neigh)
- {
- return timer_pending(&neigh->ftimer);
- }
- static int rose_t0timer_running(struct rose_neigh *neigh)
- {
- return timer_pending(&neigh->t0timer);
- }
- static void rose_ftimer_expiry(unsigned long param)
- {
- }
- static void rose_t0timer_expiry(unsigned long param)
- {
- struct rose_neigh *neigh = (struct rose_neigh *)param;
- rose_transmit_restart_request(neigh);
- neigh->dce_mode = 0;
- rose_start_t0timer(neigh);
- }
- /*
- * Interface to ax25_send_frame. Changes my level 2 callsign depending
- * on whether we have a global ROSE callsign or use the default port
- * callsign.
- */
- static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
- {
- ax25_address *rose_call;
- ax25_cb *ax25s;
- if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
- rose_call = (ax25_address *)neigh->dev->dev_addr;
- else
- rose_call = &rose_callsign;
- ax25s = neigh->ax25;
- neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
- if (ax25s)
- ax25_cb_put(ax25s);
- return neigh->ax25 != NULL;
- }
- /*
- * Interface to ax25_link_up. Changes my level 2 callsign depending
- * on whether we have a global ROSE callsign or use the default port
- * callsign.
- */
- static int rose_link_up(struct rose_neigh *neigh)
- {
- ax25_address *rose_call;
- ax25_cb *ax25s;
- if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
- rose_call = (ax25_address *)neigh->dev->dev_addr;
- else
- rose_call = &rose_callsign;
- ax25s = neigh->ax25;
- neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
- if (ax25s)
- ax25_cb_put(ax25s);
- return neigh->ax25 != NULL;
- }
- /*
- * This handles all restart and diagnostic frames.
- */
- void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype)
- {
- struct sk_buff *skbn;
- switch (frametype) {
- case ROSE_RESTART_REQUEST:
- rose_stop_t0timer(neigh);
- neigh->restarted = 1;
- neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED);
- rose_transmit_restart_confirmation(neigh);
- break;
- case ROSE_RESTART_CONFIRMATION:
- rose_stop_t0timer(neigh);
- neigh->restarted = 1;
- break;
- case ROSE_DIAGNOSTIC:
- printk(KERN_WARNING "ROSE: received diagnostic #%d - %02X %02X %02X\n", skb->data[3], skb->data[4], skb->data[5], skb->data[6]);
- break;
- default:
- printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
- break;
- }
- if (neigh->restarted) {
- while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
- if (!rose_send_frame(skbn, neigh))
- kfree_skb(skbn);
- }
- }
- /*
- * This routine is called when a Restart Request is needed
- */
- static void rose_transmit_restart_request(struct rose_neigh *neigh)
- {
- struct sk_buff *skb;
- unsigned char *dptr;
- int len;
- len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
- if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
- return;
- skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
- dptr = skb_put(skb, ROSE_MIN_LEN + 3);
- *dptr++ = AX25_P_ROSE;
- *dptr++ = ROSE_GFI;
- *dptr++ = 0x00;
- *dptr++ = ROSE_RESTART_REQUEST;
- *dptr++ = ROSE_DTE_ORIGINATED;
- *dptr++ = 0;
- if (!rose_send_frame(skb, neigh))
- kfree_skb(skb);
- }
- /*
- * This routine is called when a Restart Confirmation is needed
- */
- static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
- {
- struct sk_buff *skb;
- unsigned char *dptr;
- int len;
- len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
- if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
- return;
- skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
- dptr = skb_put(skb, ROSE_MIN_LEN + 1);
- *dptr++ = AX25_P_ROSE;
- *dptr++ = ROSE_GFI;
- *dptr++ = 0x00;
- *dptr++ = ROSE_RESTART_CONFIRMATION;
- if (!rose_send_frame(skb, neigh))
- kfree_skb(skb);
- }
- /*
- * This routine is called when a Clear Request is needed outside of the context
- * of a connected socket.
- */
- void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
- {
- struct sk_buff *skb;
- unsigned char *dptr;
- int len;
- len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
- if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
- return;
- skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
- dptr = skb_put(skb, ROSE_MIN_LEN + 3);
- *dptr++ = AX25_P_ROSE;
- *dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI;
- *dptr++ = ((lci >> 0) & 0xFF);
- *dptr++ = ROSE_CLEAR_REQUEST;
- *dptr++ = cause;
- *dptr++ = diagnostic;
- if (!rose_send_frame(skb, neigh))
- kfree_skb(skb);
- }
- void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
- {
- unsigned char *dptr;
- if (neigh->loopback) {
- rose_loopback_queue(skb, neigh);
- return;
- }
- if (!rose_link_up(neigh))
- neigh->restarted = 0;
- dptr = skb_push(skb, 1);
- *dptr++ = AX25_P_ROSE;
- if (neigh->restarted) {
- if (!rose_send_frame(skb, neigh))
- kfree_skb(skb);
- } else {
- skb_queue_tail(&neigh->queue, skb);
- if (!rose_t0timer_running(neigh)) {
- rose_transmit_restart_request(neigh);
- neigh->dce_mode = 0;
- rose_start_t0timer(neigh);
- }
- }
- }