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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright (C) Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
5 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
6 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
7 */
8#include <linux/errno.h>
9#include <linux/types.h>
10#include <linux/socket.h>
11#include <linux/in.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/timer.h>
15#include <linux/string.h>
16#include <linux/sockios.h>
17#include <linux/spinlock.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 <linux/uaccess.h>
26#include <linux/fcntl.h>
27#include <linux/mm.h>
28#include <linux/interrupt.h>
29
30static DEFINE_SPINLOCK(ax25_frag_lock);
31
32ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, const ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev)
33{
34 ax25_dev *ax25_dev;
35 ax25_cb *ax25;
36
37 /*
38 * Take the default packet length for the device if zero is
39 * specified.
40 */
41 if (paclen == 0) {
42 rcu_read_lock();
43 ax25_dev = ax25_dev_ax25dev(dev);
44 if (!ax25_dev) {
45 rcu_read_unlock();
46 return NULL;
47 }
48 paclen = ax25_dev->values[AX25_VALUES_PACLEN];
49 rcu_read_unlock();
50 }
51
52 /*
53 * Look for an existing connection.
54 */
55 if ((ax25 = ax25_find_cb(src, dest, digi, dev)) != NULL) {
56 ax25_output(ax25, paclen, skb);
57 return ax25; /* It already existed */
58 }
59
60 rcu_read_lock();
61 ax25_dev = ax25_dev_ax25dev(dev);
62 if (!ax25_dev) {
63 rcu_read_unlock();
64 return NULL;
65 }
66
67 if ((ax25 = ax25_create_cb()) == NULL) {
68 rcu_read_unlock();
69 return NULL;
70 }
71 ax25_fillin_cb(ax25, ax25_dev);
72 rcu_read_unlock();
73
74 ax25->source_addr = *src;
75 ax25->dest_addr = *dest;
76
77 if (digi != NULL) {
78 ax25->digipeat = kmemdup(digi, sizeof(*digi), GFP_ATOMIC);
79 if (ax25->digipeat == NULL) {
80 ax25_cb_put(ax25);
81 return NULL;
82 }
83 }
84
85 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
86 case AX25_PROTO_STD_SIMPLEX:
87 case AX25_PROTO_STD_DUPLEX:
88 ax25_std_establish_data_link(ax25);
89 break;
90
91#ifdef CONFIG_AX25_DAMA_SLAVE
92 case AX25_PROTO_DAMA_SLAVE:
93 if (ax25_dev->dama.slave)
94 ax25_ds_establish_data_link(ax25);
95 else
96 ax25_std_establish_data_link(ax25);
97 break;
98#endif
99 }
100
101 /*
102 * There is one ref for the state machine; a caller needs
103 * one more to put it back, just like with the existing one.
104 */
105 ax25_cb_hold(ax25);
106
107 ax25_cb_add(ax25);
108
109 ax25->state = AX25_STATE_1;
110
111 ax25_start_heartbeat(ax25);
112
113 ax25_output(ax25, paclen, skb);
114
115 return ax25; /* We had to create it */
116}
117
118EXPORT_SYMBOL(ax25_send_frame);
119
120/*
121 * All outgoing AX.25 I frames pass via this routine. Therefore this is
122 * where the fragmentation of frames takes place. If fragment is set to
123 * zero then we are not allowed to do fragmentation, even if the frame
124 * is too large.
125 */
126void ax25_output(ax25_cb *ax25, int paclen, struct sk_buff *skb)
127{
128 struct sk_buff *skbn;
129 unsigned char *p;
130 int frontlen, len, fragno, ka9qfrag, first = 1;
131
132 if (paclen < 16) {
133 WARN_ON_ONCE(1);
134 kfree_skb(skb);
135 return;
136 }
137
138 if ((skb->len - 1) > paclen) {
139 if (*skb->data == AX25_P_TEXT) {
140 skb_pull(skb, 1); /* skip PID */
141 ka9qfrag = 0;
142 } else {
143 paclen -= 2; /* Allow for fragment control info */
144 ka9qfrag = 1;
145 }
146
147 fragno = skb->len / paclen;
148 if (skb->len % paclen == 0) fragno--;
149
150 frontlen = skb_headroom(skb); /* Address space + CTRL */
151
152 while (skb->len > 0) {
153 spin_lock_bh(&ax25_frag_lock);
154 if ((skbn = alloc_skb(paclen + 2 + frontlen, GFP_ATOMIC)) == NULL) {
155 spin_unlock_bh(&ax25_frag_lock);
156 printk(KERN_CRIT "AX.25: ax25_output - out of memory\n");
157 return;
158 }
159
160 if (skb->sk != NULL)
161 skb_set_owner_w(skbn, skb->sk);
162
163 spin_unlock_bh(&ax25_frag_lock);
164
165 len = (paclen > skb->len) ? skb->len : paclen;
166
167 if (ka9qfrag == 1) {
168 skb_reserve(skbn, frontlen + 2);
169 skb_set_network_header(skbn,
170 skb_network_offset(skb));
171 skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
172 p = skb_push(skbn, 2);
173
174 *p++ = AX25_P_SEGMENT;
175
176 *p = fragno--;
177 if (first) {
178 *p |= AX25_SEG_FIRST;
179 first = 0;
180 }
181 } else {
182 skb_reserve(skbn, frontlen + 1);
183 skb_set_network_header(skbn,
184 skb_network_offset(skb));
185 skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
186 p = skb_push(skbn, 1);
187 *p = AX25_P_TEXT;
188 }
189
190 skb_pull(skb, len);
191 skb_queue_tail(&ax25->write_queue, skbn); /* Throw it on the queue */
192 }
193
194 kfree_skb(skb);
195 } else {
196 skb_queue_tail(&ax25->write_queue, skb); /* Throw it on the queue */
197 }
198
199 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
200 case AX25_PROTO_STD_SIMPLEX:
201 case AX25_PROTO_STD_DUPLEX:
202 ax25_kick(ax25);
203 break;
204
205#ifdef CONFIG_AX25_DAMA_SLAVE
206 /*
207 * A DAMA slave is _required_ to work as normal AX.25L2V2
208 * if no DAMA master is available.
209 */
210 case AX25_PROTO_DAMA_SLAVE:
211 if (!ax25->ax25_dev->dama.slave) ax25_kick(ax25);
212 break;
213#endif
214 }
215}
216
217/*
218 * This procedure is passed a buffer descriptor for an iframe. It builds
219 * the rest of the control part of the frame and then writes it out.
220 */
221static void ax25_send_iframe(ax25_cb *ax25, struct sk_buff *skb, int poll_bit)
222{
223 unsigned char *frame;
224
225 if (skb == NULL)
226 return;
227
228 skb_reset_network_header(skb);
229
230 if (ax25->modulus == AX25_MODULUS) {
231 frame = skb_push(skb, 1);
232
233 *frame = AX25_I;
234 *frame |= (poll_bit) ? AX25_PF : 0;
235 *frame |= (ax25->vr << 5);
236 *frame |= (ax25->vs << 1);
237 } else {
238 frame = skb_push(skb, 2);
239
240 frame[0] = AX25_I;
241 frame[0] |= (ax25->vs << 1);
242 frame[1] = (poll_bit) ? AX25_EPF : 0;
243 frame[1] |= (ax25->vr << 1);
244 }
245
246 ax25_start_idletimer(ax25);
247
248 ax25_transmit_buffer(ax25, skb, AX25_COMMAND);
249}
250
251void ax25_kick(ax25_cb *ax25)
252{
253 struct sk_buff *skb, *skbn;
254 int last = 1;
255 unsigned short start, end, next;
256
257 if (ax25->state != AX25_STATE_3 && ax25->state != AX25_STATE_4)
258 return;
259
260 if (ax25->condition & AX25_COND_PEER_RX_BUSY)
261 return;
262
263 if (skb_peek(&ax25->write_queue) == NULL)
264 return;
265
266 start = (skb_peek(&ax25->ack_queue) == NULL) ? ax25->va : ax25->vs;
267 end = (ax25->va + ax25->window) % ax25->modulus;
268
269 if (start == end)
270 return;
271
272 /*
273 * Transmit data until either we're out of data to send or
274 * the window is full. Send a poll on the final I frame if
275 * the window is filled.
276 */
277
278 /*
279 * Dequeue the frame and copy it.
280 * Check for race with ax25_clear_queues().
281 */
282 skb = skb_dequeue(&ax25->write_queue);
283 if (!skb)
284 return;
285
286 ax25->vs = start;
287
288 do {
289 if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
290 skb_queue_head(&ax25->write_queue, skb);
291 break;
292 }
293
294 if (skb->sk != NULL)
295 skb_set_owner_w(skbn, skb->sk);
296
297 next = (ax25->vs + 1) % ax25->modulus;
298 last = (next == end);
299
300 /*
301 * Transmit the frame copy.
302 * bke 960114: do not set the Poll bit on the last frame
303 * in DAMA mode.
304 */
305 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
306 case AX25_PROTO_STD_SIMPLEX:
307 case AX25_PROTO_STD_DUPLEX:
308 ax25_send_iframe(ax25, skbn, (last) ? AX25_POLLON : AX25_POLLOFF);
309 break;
310
311#ifdef CONFIG_AX25_DAMA_SLAVE
312 case AX25_PROTO_DAMA_SLAVE:
313 ax25_send_iframe(ax25, skbn, AX25_POLLOFF);
314 break;
315#endif
316 }
317
318 ax25->vs = next;
319
320 /*
321 * Requeue the original data frame.
322 */
323 skb_queue_tail(&ax25->ack_queue, skb);
324
325 } while (!last && (skb = skb_dequeue(&ax25->write_queue)) != NULL);
326
327 ax25->condition &= ~AX25_COND_ACK_PENDING;
328
329 if (!ax25_t1timer_running(ax25)) {
330 ax25_stop_t3timer(ax25);
331 ax25_calculate_t1(ax25);
332 ax25_start_t1timer(ax25);
333 }
334}
335
336void ax25_transmit_buffer(ax25_cb *ax25, struct sk_buff *skb, int type)
337{
338 unsigned char *ptr;
339 int headroom;
340
341 if (ax25->ax25_dev == NULL) {
342 ax25_disconnect(ax25, ENETUNREACH);
343 return;
344 }
345
346 headroom = ax25_addr_size(ax25->digipeat);
347
348 if (unlikely(skb_headroom(skb) < headroom)) {
349 skb = skb_expand_head(skb, headroom);
350 if (!skb) {
351 printk(KERN_CRIT "AX.25: ax25_transmit_buffer - out of memory\n");
352 return;
353 }
354 }
355
356 ptr = skb_push(skb, headroom);
357
358 ax25_addr_build(ptr, &ax25->source_addr, &ax25->dest_addr, ax25->digipeat, type, ax25->modulus);
359
360 ax25_queue_xmit(skb, ax25->ax25_dev->dev);
361}
362
363/*
364 * A small shim to dev_queue_xmit to add the KISS control byte, and do
365 * any packet forwarding in operation.
366 */
367void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev)
368{
369 unsigned char *ptr;
370
371 rcu_read_lock();
372 skb->protocol = ax25_type_trans(skb, ax25_fwd_dev(dev));
373 rcu_read_unlock();
374
375 ptr = skb_push(skb, 1);
376 *ptr = 0x00; /* KISS */
377
378 dev_queue_xmit(skb);
379}
380
381int ax25_check_iframes_acked(ax25_cb *ax25, unsigned short nr)
382{
383 if (ax25->vs == nr) {
384 ax25_frames_acked(ax25, nr);
385 ax25_calculate_rtt(ax25);
386 ax25_stop_t1timer(ax25);
387 ax25_start_t3timer(ax25);
388 return 1;
389 } else {
390 if (ax25->va != nr) {
391 ax25_frames_acked(ax25, nr);
392 ax25_calculate_t1(ax25);
393 ax25_start_t1timer(ax25);
394 return 1;
395 }
396 }
397 return 0;
398}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright (C) Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
5 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
6 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
7 */
8#include <linux/errno.h>
9#include <linux/types.h>
10#include <linux/socket.h>
11#include <linux/in.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/timer.h>
15#include <linux/string.h>
16#include <linux/sockios.h>
17#include <linux/spinlock.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 <linux/uaccess.h>
26#include <linux/fcntl.h>
27#include <linux/mm.h>
28#include <linux/interrupt.h>
29
30static DEFINE_SPINLOCK(ax25_frag_lock);
31
32ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, const ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev)
33{
34 ax25_dev *ax25_dev;
35 ax25_cb *ax25;
36
37 /*
38 * Take the default packet length for the device if zero is
39 * specified.
40 */
41 if (paclen == 0) {
42 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
43 return NULL;
44
45 paclen = ax25_dev->values[AX25_VALUES_PACLEN];
46 }
47
48 /*
49 * Look for an existing connection.
50 */
51 if ((ax25 = ax25_find_cb(src, dest, digi, dev)) != NULL) {
52 ax25_output(ax25, paclen, skb);
53 return ax25; /* It already existed */
54 }
55
56 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
57 return NULL;
58
59 if ((ax25 = ax25_create_cb()) == NULL)
60 return NULL;
61
62 ax25_fillin_cb(ax25, ax25_dev);
63
64 ax25->source_addr = *src;
65 ax25->dest_addr = *dest;
66
67 if (digi != NULL) {
68 ax25->digipeat = kmemdup(digi, sizeof(*digi), GFP_ATOMIC);
69 if (ax25->digipeat == NULL) {
70 ax25_cb_put(ax25);
71 return NULL;
72 }
73 }
74
75 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
76 case AX25_PROTO_STD_SIMPLEX:
77 case AX25_PROTO_STD_DUPLEX:
78 ax25_std_establish_data_link(ax25);
79 break;
80
81#ifdef CONFIG_AX25_DAMA_SLAVE
82 case AX25_PROTO_DAMA_SLAVE:
83 if (ax25_dev->dama.slave)
84 ax25_ds_establish_data_link(ax25);
85 else
86 ax25_std_establish_data_link(ax25);
87 break;
88#endif
89 }
90
91 /*
92 * There is one ref for the state machine; a caller needs
93 * one more to put it back, just like with the existing one.
94 */
95 ax25_cb_hold(ax25);
96
97 ax25_cb_add(ax25);
98
99 ax25->state = AX25_STATE_1;
100
101 ax25_start_heartbeat(ax25);
102
103 ax25_output(ax25, paclen, skb);
104
105 return ax25; /* We had to create it */
106}
107
108EXPORT_SYMBOL(ax25_send_frame);
109
110/*
111 * All outgoing AX.25 I frames pass via this routine. Therefore this is
112 * where the fragmentation of frames takes place. If fragment is set to
113 * zero then we are not allowed to do fragmentation, even if the frame
114 * is too large.
115 */
116void ax25_output(ax25_cb *ax25, int paclen, struct sk_buff *skb)
117{
118 struct sk_buff *skbn;
119 unsigned char *p;
120 int frontlen, len, fragno, ka9qfrag, first = 1;
121
122 if (paclen < 16) {
123 WARN_ON_ONCE(1);
124 kfree_skb(skb);
125 return;
126 }
127
128 if ((skb->len - 1) > paclen) {
129 if (*skb->data == AX25_P_TEXT) {
130 skb_pull(skb, 1); /* skip PID */
131 ka9qfrag = 0;
132 } else {
133 paclen -= 2; /* Allow for fragment control info */
134 ka9qfrag = 1;
135 }
136
137 fragno = skb->len / paclen;
138 if (skb->len % paclen == 0) fragno--;
139
140 frontlen = skb_headroom(skb); /* Address space + CTRL */
141
142 while (skb->len > 0) {
143 spin_lock_bh(&ax25_frag_lock);
144 if ((skbn = alloc_skb(paclen + 2 + frontlen, GFP_ATOMIC)) == NULL) {
145 spin_unlock_bh(&ax25_frag_lock);
146 printk(KERN_CRIT "AX.25: ax25_output - out of memory\n");
147 return;
148 }
149
150 if (skb->sk != NULL)
151 skb_set_owner_w(skbn, skb->sk);
152
153 spin_unlock_bh(&ax25_frag_lock);
154
155 len = (paclen > skb->len) ? skb->len : paclen;
156
157 if (ka9qfrag == 1) {
158 skb_reserve(skbn, frontlen + 2);
159 skb_set_network_header(skbn,
160 skb_network_offset(skb));
161 skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
162 p = skb_push(skbn, 2);
163
164 *p++ = AX25_P_SEGMENT;
165
166 *p = fragno--;
167 if (first) {
168 *p |= AX25_SEG_FIRST;
169 first = 0;
170 }
171 } else {
172 skb_reserve(skbn, frontlen + 1);
173 skb_set_network_header(skbn,
174 skb_network_offset(skb));
175 skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
176 p = skb_push(skbn, 1);
177 *p = AX25_P_TEXT;
178 }
179
180 skb_pull(skb, len);
181 skb_queue_tail(&ax25->write_queue, skbn); /* Throw it on the queue */
182 }
183
184 kfree_skb(skb);
185 } else {
186 skb_queue_tail(&ax25->write_queue, skb); /* Throw it on the queue */
187 }
188
189 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
190 case AX25_PROTO_STD_SIMPLEX:
191 case AX25_PROTO_STD_DUPLEX:
192 ax25_kick(ax25);
193 break;
194
195#ifdef CONFIG_AX25_DAMA_SLAVE
196 /*
197 * A DAMA slave is _required_ to work as normal AX.25L2V2
198 * if no DAMA master is available.
199 */
200 case AX25_PROTO_DAMA_SLAVE:
201 if (!ax25->ax25_dev->dama.slave) ax25_kick(ax25);
202 break;
203#endif
204 }
205}
206
207/*
208 * This procedure is passed a buffer descriptor for an iframe. It builds
209 * the rest of the control part of the frame and then writes it out.
210 */
211static void ax25_send_iframe(ax25_cb *ax25, struct sk_buff *skb, int poll_bit)
212{
213 unsigned char *frame;
214
215 if (skb == NULL)
216 return;
217
218 skb_reset_network_header(skb);
219
220 if (ax25->modulus == AX25_MODULUS) {
221 frame = skb_push(skb, 1);
222
223 *frame = AX25_I;
224 *frame |= (poll_bit) ? AX25_PF : 0;
225 *frame |= (ax25->vr << 5);
226 *frame |= (ax25->vs << 1);
227 } else {
228 frame = skb_push(skb, 2);
229
230 frame[0] = AX25_I;
231 frame[0] |= (ax25->vs << 1);
232 frame[1] = (poll_bit) ? AX25_EPF : 0;
233 frame[1] |= (ax25->vr << 1);
234 }
235
236 ax25_start_idletimer(ax25);
237
238 ax25_transmit_buffer(ax25, skb, AX25_COMMAND);
239}
240
241void ax25_kick(ax25_cb *ax25)
242{
243 struct sk_buff *skb, *skbn;
244 int last = 1;
245 unsigned short start, end, next;
246
247 if (ax25->state != AX25_STATE_3 && ax25->state != AX25_STATE_4)
248 return;
249
250 if (ax25->condition & AX25_COND_PEER_RX_BUSY)
251 return;
252
253 if (skb_peek(&ax25->write_queue) == NULL)
254 return;
255
256 start = (skb_peek(&ax25->ack_queue) == NULL) ? ax25->va : ax25->vs;
257 end = (ax25->va + ax25->window) % ax25->modulus;
258
259 if (start == end)
260 return;
261
262 /*
263 * Transmit data until either we're out of data to send or
264 * the window is full. Send a poll on the final I frame if
265 * the window is filled.
266 */
267
268 /*
269 * Dequeue the frame and copy it.
270 * Check for race with ax25_clear_queues().
271 */
272 skb = skb_dequeue(&ax25->write_queue);
273 if (!skb)
274 return;
275
276 ax25->vs = start;
277
278 do {
279 if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
280 skb_queue_head(&ax25->write_queue, skb);
281 break;
282 }
283
284 if (skb->sk != NULL)
285 skb_set_owner_w(skbn, skb->sk);
286
287 next = (ax25->vs + 1) % ax25->modulus;
288 last = (next == end);
289
290 /*
291 * Transmit the frame copy.
292 * bke 960114: do not set the Poll bit on the last frame
293 * in DAMA mode.
294 */
295 switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) {
296 case AX25_PROTO_STD_SIMPLEX:
297 case AX25_PROTO_STD_DUPLEX:
298 ax25_send_iframe(ax25, skbn, (last) ? AX25_POLLON : AX25_POLLOFF);
299 break;
300
301#ifdef CONFIG_AX25_DAMA_SLAVE
302 case AX25_PROTO_DAMA_SLAVE:
303 ax25_send_iframe(ax25, skbn, AX25_POLLOFF);
304 break;
305#endif
306 }
307
308 ax25->vs = next;
309
310 /*
311 * Requeue the original data frame.
312 */
313 skb_queue_tail(&ax25->ack_queue, skb);
314
315 } while (!last && (skb = skb_dequeue(&ax25->write_queue)) != NULL);
316
317 ax25->condition &= ~AX25_COND_ACK_PENDING;
318
319 if (!ax25_t1timer_running(ax25)) {
320 ax25_stop_t3timer(ax25);
321 ax25_calculate_t1(ax25);
322 ax25_start_t1timer(ax25);
323 }
324}
325
326void ax25_transmit_buffer(ax25_cb *ax25, struct sk_buff *skb, int type)
327{
328 unsigned char *ptr;
329 int headroom;
330
331 if (ax25->ax25_dev == NULL) {
332 ax25_disconnect(ax25, ENETUNREACH);
333 return;
334 }
335
336 headroom = ax25_addr_size(ax25->digipeat);
337
338 if (unlikely(skb_headroom(skb) < headroom)) {
339 skb = skb_expand_head(skb, headroom);
340 if (!skb) {
341 printk(KERN_CRIT "AX.25: ax25_transmit_buffer - out of memory\n");
342 return;
343 }
344 }
345
346 ptr = skb_push(skb, headroom);
347
348 ax25_addr_build(ptr, &ax25->source_addr, &ax25->dest_addr, ax25->digipeat, type, ax25->modulus);
349
350 ax25_queue_xmit(skb, ax25->ax25_dev->dev);
351}
352
353/*
354 * A small shim to dev_queue_xmit to add the KISS control byte, and do
355 * any packet forwarding in operation.
356 */
357void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev)
358{
359 unsigned char *ptr;
360
361 skb->protocol = ax25_type_trans(skb, ax25_fwd_dev(dev));
362
363 ptr = skb_push(skb, 1);
364 *ptr = 0x00; /* KISS */
365
366 dev_queue_xmit(skb);
367}
368
369int ax25_check_iframes_acked(ax25_cb *ax25, unsigned short nr)
370{
371 if (ax25->vs == nr) {
372 ax25_frames_acked(ax25, nr);
373 ax25_calculate_rtt(ax25);
374 ax25_stop_t1timer(ax25);
375 ax25_start_t3timer(ax25);
376 return 1;
377 } else {
378 if (ax25->va != nr) {
379 ax25_frames_acked(ax25, nr);
380 ax25_calculate_t1(ax25);
381 ax25_start_t1timer(ax25);
382 return 1;
383 }
384 }
385 return 0;
386}