1/* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License as published by 4 * the Free Software Foundation; either version 2 of the License, or 5 * (at your option) any later version. 6 * 7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 8 */ 9#include <linux/errno.h> 10#include <linux/types.h> 11#include <linux/socket.h> 12#include <linux/in.h> 13#include <linux/kernel.h> 14#include <linux/jiffies.h> 15#include <linux/timer.h> 16#include <linux/string.h> 17#include <linux/sockios.h> 18#include <linux/net.h> 19#include <linux/slab.h> 20#include <net/ax25.h> 21#include <linux/inet.h> 22#include <linux/netdevice.h> 23#include <linux/skbuff.h> 24#include <net/sock.h> 25#include <asm/system.h> 26#include <linux/fcntl.h> 27#include <linux/mm.h> 28#include <linux/interrupt.h> 29#include <linux/netfilter.h> 30#include <net/rose.h> 31 32static void rose_ftimer_expiry(unsigned long); 33static void rose_t0timer_expiry(unsigned long); 34 35static void rose_transmit_restart_confirmation(struct rose_neigh *neigh); 36static void rose_transmit_restart_request(struct rose_neigh *neigh); 37 38void rose_start_ftimer(struct rose_neigh *neigh) 39{ 40 del_timer(&neigh->ftimer); 41 42 neigh->ftimer.data = (unsigned long)neigh; 43 neigh->ftimer.function = &rose_ftimer_expiry; 44 neigh->ftimer.expires = 45 jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout); 46 47 add_timer(&neigh->ftimer); 48} 49 50static void rose_start_t0timer(struct rose_neigh *neigh) 51{ 52 del_timer(&neigh->t0timer); 53 54 neigh->t0timer.data = (unsigned long)neigh; 55 neigh->t0timer.function = &rose_t0timer_expiry; 56 neigh->t0timer.expires = 57 jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout); 58 59 add_timer(&neigh->t0timer); 60} 61 62void rose_stop_ftimer(struct rose_neigh *neigh) 63{ 64 del_timer(&neigh->ftimer); 65} 66 67void rose_stop_t0timer(struct rose_neigh *neigh) 68{ 69 del_timer(&neigh->t0timer); 70} 71 72int rose_ftimer_running(struct rose_neigh *neigh) 73{ 74 return timer_pending(&neigh->ftimer); 75} 76 77static int rose_t0timer_running(struct rose_neigh *neigh) 78{ 79 return timer_pending(&neigh->t0timer); 80} 81 82static void rose_ftimer_expiry(unsigned long param) 83{ 84} 85 86static void rose_t0timer_expiry(unsigned long param) 87{ 88 struct rose_neigh *neigh = (struct rose_neigh *)param; 89 90 rose_transmit_restart_request(neigh); 91 92 neigh->dce_mode = 0; 93 94 rose_start_t0timer(neigh); 95} 96 97/* 98 * Interface to ax25_send_frame. Changes my level 2 callsign depending 99 * on whether we have a global ROSE callsign or use the default port 100 * callsign. 101 */ 102static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh) 103{ 104 ax25_address *rose_call; 105 ax25_cb *ax25s; 106 107 if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) 108 rose_call = (ax25_address *)neigh->dev->dev_addr; 109 else 110 rose_call = &rose_callsign; 111 112 ax25s = neigh->ax25; 113 neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); 114 if (ax25s) 115 ax25_cb_put(ax25s); 116 117 return (neigh->ax25 != NULL); 118} 119 120/* 121 * Interface to ax25_link_up. Changes my level 2 callsign depending 122 * on whether we have a global ROSE callsign or use the default port 123 * callsign. 124 */ 125static int rose_link_up(struct rose_neigh *neigh) 126{ 127 ax25_address *rose_call; 128 ax25_cb *ax25s; 129 130 if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) 131 rose_call = (ax25_address *)neigh->dev->dev_addr; 132 else 133 rose_call = &rose_callsign; 134 135 ax25s = neigh->ax25; 136 neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); 137 if (ax25s) 138 ax25_cb_put(ax25s); 139 140 return (neigh->ax25 != NULL); 141} 142 143/* 144 * This handles all restart and diagnostic frames. 145 */ 146void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype) 147{ 148 struct sk_buff *skbn; 149 150 switch (frametype) { 151 case ROSE_RESTART_REQUEST: 152 rose_stop_t0timer(neigh); 153 neigh->restarted = 1; 154 neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED); 155 rose_transmit_restart_confirmation(neigh); 156 break; 157 158 case ROSE_RESTART_CONFIRMATION: 159 rose_stop_t0timer(neigh); 160 neigh->restarted = 1; 161 break; 162 163 case ROSE_DIAGNOSTIC: 164 printk(KERN_WARNING "ROSE: received diagnostic #%d - %02X %02X %02X\n", skb->data[3], skb->data[4], skb->data[5], skb->data[6]); 165 break; 166 167 default: 168 printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype); 169 break; 170 } 171 172 if (neigh->restarted) { 173 while ((skbn = skb_dequeue(&neigh->queue)) != NULL) 174 if (!rose_send_frame(skbn, neigh)) 175 kfree_skb(skbn); 176 } 177} 178 179/* 180 * This routine is called when a Restart Request is needed 181 */ 182static void rose_transmit_restart_request(struct rose_neigh *neigh) 183{ 184 struct sk_buff *skb; 185 unsigned char *dptr; 186 int len; 187 188 len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3; 189 190 if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) 191 return; 192 193 skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); 194 195 dptr = skb_put(skb, ROSE_MIN_LEN + 3); 196 197 *dptr++ = AX25_P_ROSE; 198 *dptr++ = ROSE_GFI; 199 *dptr++ = 0x00; 200 *dptr++ = ROSE_RESTART_REQUEST; 201 *dptr++ = ROSE_DTE_ORIGINATED; 202 *dptr++ = 0; 203 204 if (!rose_send_frame(skb, neigh)) 205 kfree_skb(skb); 206} 207 208/* 209 * This routine is called when a Restart Confirmation is needed 210 */ 211static void rose_transmit_restart_confirmation(struct rose_neigh *neigh) 212{ 213 struct sk_buff *skb; 214 unsigned char *dptr; 215 int len; 216 217 len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1; 218 219 if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) 220 return; 221 222 skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); 223 224 dptr = skb_put(skb, ROSE_MIN_LEN + 1); 225 226 *dptr++ = AX25_P_ROSE; 227 *dptr++ = ROSE_GFI; 228 *dptr++ = 0x00; 229 *dptr++ = ROSE_RESTART_CONFIRMATION; 230 231 if (!rose_send_frame(skb, neigh)) 232 kfree_skb(skb); 233} 234 235/* 236 * This routine is called when a Clear Request is needed outside of the context 237 * of a connected socket. 238 */ 239void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic) 240{ 241 struct sk_buff *skb; 242 unsigned char *dptr; 243 int len; 244 245 len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3; 246 247 if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) 248 return; 249 250 skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); 251 252 dptr = skb_put(skb, ROSE_MIN_LEN + 3); 253 254 *dptr++ = AX25_P_ROSE; 255 *dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI; 256 *dptr++ = ((lci >> 0) & 0xFF); 257 *dptr++ = ROSE_CLEAR_REQUEST; 258 *dptr++ = cause; 259 *dptr++ = diagnostic; 260 261 if (!rose_send_frame(skb, neigh)) 262 kfree_skb(skb); 263} 264 265void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh) 266{ 267 unsigned char *dptr; 268 269 270 if (neigh->loopback) { 271 rose_loopback_queue(skb, neigh); 272 return; 273 } 274 275 if (!rose_link_up(neigh)) 276 neigh->restarted = 0; 277 278 dptr = skb_push(skb, 1); 279 *dptr++ = AX25_P_ROSE; 280 281 if (neigh->restarted) { 282 if (!rose_send_frame(skb, neigh)) 283 kfree_skb(skb); 284 } else { 285 skb_queue_tail(&neigh->queue, skb); 286 287 if (!rose_t0timer_running(neigh)) { 288 rose_transmit_restart_request(neigh); 289 neigh->dce_mode = 0; 290 rose_start_t0timer(neigh); 291 } 292 } 293} 294