Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / net / rose / rose_link.c
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 <net/ax25.h>
20 #include <linux/inet.h>
21 #include <linux/netdevice.h>
22 #include <linux/skbuff.h>
23 #include <net/sock.h>
24 #include <asm/system.h>
25 #include <linux/fcntl.h>
26 #include <linux/mm.h>
27 #include <linux/interrupt.h>
28 #include <linux/netfilter.h>
29 #include <net/rose.h>
30
31 static void rose_ftimer_expiry(unsigned long);
32 static void rose_t0timer_expiry(unsigned long);
33
34 static void rose_transmit_restart_confirmation(struct rose_neigh *neigh);
35 static void rose_transmit_restart_request(struct rose_neigh *neigh);
36
37 void rose_start_ftimer(struct rose_neigh *neigh)
38 {
39         del_timer(&neigh->ftimer);
40
41         neigh->ftimer.data     = (unsigned long)neigh;
42         neigh->ftimer.function = &rose_ftimer_expiry;
43         neigh->ftimer.expires  =
44                 jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);
45
46         add_timer(&neigh->ftimer);
47 }
48
49 static void rose_start_t0timer(struct rose_neigh *neigh)
50 {
51         del_timer(&neigh->t0timer);
52
53         neigh->t0timer.data     = (unsigned long)neigh;
54         neigh->t0timer.function = &rose_t0timer_expiry;
55         neigh->t0timer.expires  =
56                 jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);
57
58         add_timer(&neigh->t0timer);
59 }
60
61 void rose_stop_ftimer(struct rose_neigh *neigh)
62 {
63         del_timer(&neigh->ftimer);
64 }
65
66 void rose_stop_t0timer(struct rose_neigh *neigh)
67 {
68         del_timer(&neigh->t0timer);
69 }
70
71 int rose_ftimer_running(struct rose_neigh *neigh)
72 {
73         return timer_pending(&neigh->ftimer);
74 }
75
76 static int rose_t0timer_running(struct rose_neigh *neigh)
77 {
78         return timer_pending(&neigh->t0timer);
79 }
80
81 static void rose_ftimer_expiry(unsigned long param)
82 {
83 }
84
85 static void rose_t0timer_expiry(unsigned long param)
86 {
87         struct rose_neigh *neigh = (struct rose_neigh *)param;
88
89         rose_transmit_restart_request(neigh);
90
91         neigh->dce_mode = 0;
92
93         rose_start_t0timer(neigh);
94 }
95
96 /*
97  *      Interface to ax25_send_frame. Changes my level 2 callsign depending
98  *      on whether we have a global ROSE callsign or use the default port
99  *      callsign.
100  */
101 static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
102 {
103         ax25_address *rose_call;
104         ax25_cb *ax25s;
105
106         if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
107                 rose_call = (ax25_address *)neigh->dev->dev_addr;
108         else
109                 rose_call = &rose_callsign;
110
111         ax25s = neigh->ax25;
112         neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
113         if (ax25s)
114                 ax25_cb_put(ax25s);
115
116         return (neigh->ax25 != NULL);
117 }
118
119 /*
120  *      Interface to ax25_link_up. Changes my level 2 callsign depending
121  *      on whether we have a global ROSE callsign or use the default port
122  *      callsign.
123  */
124 static int rose_link_up(struct rose_neigh *neigh)
125 {
126         ax25_address *rose_call;
127         ax25_cb *ax25s;
128
129         if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
130                 rose_call = (ax25_address *)neigh->dev->dev_addr;
131         else
132                 rose_call = &rose_callsign;
133
134         ax25s = neigh->ax25;
135         neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
136         if (ax25s)
137                 ax25_cb_put(ax25s);
138
139         return (neigh->ax25 != NULL);
140 }
141
142 /*
143  *      This handles all restart and diagnostic frames.
144  */
145 void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype)
146 {
147         struct sk_buff *skbn;
148
149         switch (frametype) {
150         case ROSE_RESTART_REQUEST:
151                 rose_stop_t0timer(neigh);
152                 neigh->restarted = 1;
153                 neigh->dce_mode  = (skb->data[3] == ROSE_DTE_ORIGINATED);
154                 rose_transmit_restart_confirmation(neigh);
155                 break;
156
157         case ROSE_RESTART_CONFIRMATION:
158                 rose_stop_t0timer(neigh);
159                 neigh->restarted = 1;
160                 break;
161
162         case ROSE_DIAGNOSTIC:
163                 printk(KERN_WARNING "ROSE: received diagnostic #%d - %02X %02X %02X\n", skb->data[3], skb->data[4], skb->data[5], skb->data[6]);
164                 break;
165
166         default:
167                 printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
168                 break;
169         }
170
171         if (neigh->restarted) {
172                 while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
173                         if (!rose_send_frame(skbn, neigh))
174                                 kfree_skb(skbn);
175         }
176 }
177
178 /*
179  *      This routine is called when a Restart Request is needed
180  */
181 static void rose_transmit_restart_request(struct rose_neigh *neigh)
182 {
183         struct sk_buff *skb;
184         unsigned char *dptr;
185         int len;
186
187         len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
188
189         if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
190                 return;
191
192         skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
193
194         dptr = skb_put(skb, ROSE_MIN_LEN + 3);
195
196         *dptr++ = AX25_P_ROSE;
197         *dptr++ = ROSE_GFI;
198         *dptr++ = 0x00;
199         *dptr++ = ROSE_RESTART_REQUEST;
200         *dptr++ = ROSE_DTE_ORIGINATED;
201         *dptr++ = 0;
202
203         if (!rose_send_frame(skb, neigh))
204                 kfree_skb(skb);
205 }
206
207 /*
208  * This routine is called when a Restart Confirmation is needed
209  */
210 static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
211 {
212         struct sk_buff *skb;
213         unsigned char *dptr;
214         int len;
215
216         len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
217
218         if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
219                 return;
220
221         skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
222
223         dptr = skb_put(skb, ROSE_MIN_LEN + 1);
224
225         *dptr++ = AX25_P_ROSE;
226         *dptr++ = ROSE_GFI;
227         *dptr++ = 0x00;
228         *dptr++ = ROSE_RESTART_CONFIRMATION;
229
230         if (!rose_send_frame(skb, neigh))
231                 kfree_skb(skb);
232 }
233
234 /*
235  * This routine is called when a Clear Request is needed outside of the context
236  * of a connected socket.
237  */
238 void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
239 {
240         struct sk_buff *skb;
241         unsigned char *dptr;
242         int len;
243
244         len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
245
246         if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
247                 return;
248
249         skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
250
251         dptr = skb_put(skb, ROSE_MIN_LEN + 3);
252
253         *dptr++ = AX25_P_ROSE;
254         *dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI;
255         *dptr++ = ((lci >> 0) & 0xFF);
256         *dptr++ = ROSE_CLEAR_REQUEST;
257         *dptr++ = cause;
258         *dptr++ = diagnostic;
259
260         if (!rose_send_frame(skb, neigh))
261                 kfree_skb(skb);
262 }
263
264 void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
265 {
266         unsigned char *dptr;
267
268 #if 0
269         if (call_fw_firewall(PF_ROSE, skb->dev, skb->data, NULL, &skb) != FW_ACCEPT) {
270                 kfree_skb(skb);
271                 return;
272         }
273 #endif
274
275         if (neigh->loopback) {
276                 rose_loopback_queue(skb, neigh);
277                 return;
278         }
279
280         if (!rose_link_up(neigh))
281                 neigh->restarted = 0;
282
283         dptr = skb_push(skb, 1);
284         *dptr++ = AX25_P_ROSE;
285
286         if (neigh->restarted) {
287                 if (!rose_send_frame(skb, neigh))
288                         kfree_skb(skb);
289         } else {
290                 skb_queue_tail(&neigh->queue, skb);
291
292                 if (!rose_t0timer_running(neigh)) {
293                         rose_transmit_restart_request(neigh);
294                         neigh->dce_mode = 0;
295                         rose_start_t0timer(neigh);
296                 }
297         }
298 }