alistair23-linux/net/rose/rose_link.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

287 lines
6.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
*
* 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 <net/rose.h>
static void rose_ftimer_expiry(struct timer_list *);
static void rose_t0timer_expiry(struct timer_list *);
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.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.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(struct timer_list *t)
{
}
static void rose_t0timer_expiry(struct timer_list *t)
{
struct rose_neigh *neigh = from_timer(neigh, t, t0timer);
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:
pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3],
skb->data + 4);
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);
}
}
}