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Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-block.git] / net / llc / llc_c_ac.c
CommitLineData
1da177e4
LT		 1/*
2 * llc_c_ac.c - actions performed during connection state transition.
3 *
4 * Description:
5 * Functions in this module are implementation of connection component actions
6 * Details of actions can be found in IEEE-802.2 standard document.
7 * All functions have one connection and one event as input argument. All of
8 * them return 0 On success and 1 otherwise.
9 *
10 * Copyright (c) 1997 by Procom Technology, Inc.
11 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
12 *
13 * This program can be redistributed or modified under the terms of the
14 * GNU General Public License as published by the Free Software Foundation.
15 * This program is distributed without any warranty or implied warranty
16 * of merchantability or fitness for a particular purpose.
17 *
18 * See the GNU General Public License for more details.
19 */
20#include <linux/netdevice.h>
5a0e3ad6 21#include <linux/slab.h>
1da177e4
LT		 22#include <net/llc_conn.h>
23#include <net/llc_sap.h>
24#include <net/sock.h>
25#include <net/llc_c_ev.h>
26#include <net/llc_c_ac.h>
27#include <net/llc_c_st.h>
28#include <net/llc_pdu.h>
29#include <net/llc.h>
30
1da177e4
LT		 31
32static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb);
33static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb);
34static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *ev);
35
36static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb);
37
38static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
39 struct sk_buff *skb);
40
41static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb);
42
43#define INCORRECT 0
44
45int llc_conn_ac_clear_remote_busy(struct sock *sk, struct sk_buff *skb)
46{
47 struct llc_sock *llc = llc_sk(sk);
48
49 if (llc->remote_busy_flag) {
50 u8 nr;
51 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
52
53 llc->remote_busy_flag = 0;
54 del_timer(&llc->busy_state_timer.timer);
55 nr = LLC_I_GET_NR(pdu);
56 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
57 }
58 return 0;
59}
60
61int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
62{
d389424e
ACM		 63 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
64
65 ev->ind_prim = LLC_CONN_PRIM;
66 return 0;
1da177e4
LT		 67}
68
69int llc_conn_ac_conn_confirm(struct sock *sk, struct sk_buff *skb)
70{
71 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
72
73 ev->cfm_prim = LLC_CONN_PRIM;
74 return 0;
75}
76
77static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *skb)
78{
79 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
80
81 ev->cfm_prim = LLC_DATA_PRIM;
82 return 0;
83}
84
85int llc_conn_ac_data_ind(struct sock *sk, struct sk_buff *skb)
86{
87 llc_conn_rtn_pdu(sk, skb);
88 return 0;
89}
90
91int llc_conn_ac_disc_ind(struct sock *sk, struct sk_buff *skb)
92{
93 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
94 u8 reason = 0;
95 int rc = 0;
96
97 if (ev->type == LLC_CONN_EV_TYPE_PDU) {
98 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
99
100 if (LLC_PDU_IS_RSP(pdu) &&
101 LLC_PDU_TYPE_IS_U(pdu) &&
102 LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_DM)
103 reason = LLC_DISC_REASON_RX_DM_RSP_PDU;
104 else if (LLC_PDU_IS_CMD(pdu) &&
105 LLC_PDU_TYPE_IS_U(pdu) &&
106 LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_DISC)
107 reason = LLC_DISC_REASON_RX_DISC_CMD_PDU;
108 } else if (ev->type == LLC_CONN_EV_TYPE_ACK_TMR)
109 reason = LLC_DISC_REASON_ACK_TMR_EXP;
bdcc66cc 110 else
1da177e4 111 rc = -EINVAL;
1da177e4
LT		 112 if (!rc) {
113 ev->reason = reason;
114 ev->ind_prim = LLC_DISC_PRIM;
115 }
116 return rc;
117}
118
119int llc_conn_ac_disc_confirm(struct sock *sk, struct sk_buff *skb)
120{
121 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
122
123 ev->reason = ev->status;
124 ev->cfm_prim = LLC_DISC_PRIM;
125 return 0;
126}
127
128int llc_conn_ac_rst_ind(struct sock *sk, struct sk_buff *skb)
129{
130 u8 reason = 0;
131 int rc = 1;
132 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
133 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
134 struct llc_sock *llc = llc_sk(sk);
135
136 switch (ev->type) {
137 case LLC_CONN_EV_TYPE_PDU:
138 if (LLC_PDU_IS_RSP(pdu) &&
139 LLC_PDU_TYPE_IS_U(pdu) &&
140 LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_FRMR) {
141 reason = LLC_RESET_REASON_LOCAL;
142 rc = 0;
143 } else if (LLC_PDU_IS_CMD(pdu) &&
144 LLC_PDU_TYPE_IS_U(pdu) &&
145 LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_SABME) {
146 reason = LLC_RESET_REASON_REMOTE;
147 rc = 0;
1da177e4
LT		 148 }
149 break;
150 case LLC_CONN_EV_TYPE_ACK_TMR:
151 case LLC_CONN_EV_TYPE_P_TMR:
152 case LLC_CONN_EV_TYPE_REJ_TMR:
153 case LLC_CONN_EV_TYPE_BUSY_TMR:
154 if (llc->retry_count > llc->n2) {
155 reason = LLC_RESET_REASON_LOCAL;
156 rc = 0;
bdcc66cc 157 }
1da177e4
LT		 158 break;
159 }
160 if (!rc) {
161 ev->reason = reason;
162 ev->ind_prim = LLC_RESET_PRIM;
163 }
164 return rc;
165}
166
167int llc_conn_ac_rst_confirm(struct sock *sk, struct sk_buff *skb)
168{
169 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
170
171 ev->reason = 0;
172 ev->cfm_prim = LLC_RESET_PRIM;
173 return 0;
174}
175
176int llc_conn_ac_clear_remote_busy_if_f_eq_1(struct sock *sk,
177 struct sk_buff *skb)
178{
179 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
180
181 if (LLC_PDU_IS_RSP(pdu) &&
182 LLC_PDU_TYPE_IS_I(pdu) &&
183 LLC_I_PF_IS_1(pdu) && llc_sk(sk)->ack_pf)
184 llc_conn_ac_clear_remote_busy(sk, skb);
185 return 0;
186}
187
188int llc_conn_ac_stop_rej_tmr_if_data_flag_eq_2(struct sock *sk,
189 struct sk_buff *skb)
190{
191 struct llc_sock *llc = llc_sk(sk);
192
193 if (llc->data_flag == 2)
194 del_timer(&llc->rej_sent_timer.timer);
195 return 0;
196}
197
198int llc_conn_ac_send_disc_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
199{
200 int rc = -ENOBUFS;
1d67e650 201 struct llc_sock *llc = llc_sk(sk);
f83f1768 202 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 203
204 if (nskb) {
1da177e4
LT		 205 struct llc_sap *sap = llc->sap;
206
1da177e4
LT		 207 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
208 llc->daddr.lsap, LLC_PDU_CMD);
209 llc_pdu_init_as_disc_cmd(nskb, 1);
210 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 211 if (unlikely(rc))
1da177e4
LT		 212 goto free;
213 llc_conn_send_pdu(sk, nskb);
214 llc_conn_ac_set_p_flag_1(sk, skb);
215 }
216out:
217 return rc;
218free:
219 kfree_skb(nskb);
220 goto out;
221}
222
223int llc_conn_ac_send_dm_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
224{
225 int rc = -ENOBUFS;
1d67e650 226 struct llc_sock *llc = llc_sk(sk);
f83f1768 227 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 228
229 if (nskb) {
1da177e4
LT		 230 struct llc_sap *sap = llc->sap;
231 u8 f_bit;
232
1da177e4
LT		 233 llc_pdu_decode_pf_bit(skb, &f_bit);
234 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
235 llc->daddr.lsap, LLC_PDU_RSP);
236 llc_pdu_init_as_dm_rsp(nskb, f_bit);
237 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 238 if (unlikely(rc))
1da177e4
LT		 239 goto free;
240 llc_conn_send_pdu(sk, nskb);
241 }
242out:
243 return rc;
244free:
245 kfree_skb(nskb);
246 goto out;
247}
248
249int llc_conn_ac_send_dm_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
250{
251 int rc = -ENOBUFS;
1d67e650 252 struct llc_sock *llc = llc_sk(sk);
f83f1768 253 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 254
255 if (nskb) {
1da177e4 256 struct llc_sap *sap = llc->sap;
1da177e4 257
1da177e4
LT		 258 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
259 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 260 llc_pdu_init_as_dm_rsp(nskb, 1);
1da177e4 261 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 262 if (unlikely(rc))
1da177e4
LT		 263 goto free;
264 llc_conn_send_pdu(sk, nskb);
265 }
266out:
267 return rc;
268free:
269 kfree_skb(nskb);
270 goto out;
271}
272
273int llc_conn_ac_send_frmr_rsp_f_set_x(struct sock *sk, struct sk_buff *skb)
274{
275 u8 f_bit;
276 int rc = -ENOBUFS;
277 struct sk_buff *nskb;
278 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
279 struct llc_sock *llc = llc_sk(sk);
280
281 llc->rx_pdu_hdr = *((u32 *)pdu);
282 if (LLC_PDU_IS_CMD(pdu))
283 llc_pdu_decode_pf_bit(skb, &f_bit);
284 else
285 f_bit = 0;
f83f1768
JP		 286 nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
287 sizeof(struct llc_frmr_info));
1da177e4
LT		 288 if (nskb) {
289 struct llc_sap *sap = llc->sap;
290
1da177e4
LT		 291 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
292 llc->daddr.lsap, LLC_PDU_RSP);
293 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
294 llc->vR, INCORRECT);
295 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 296 if (unlikely(rc))
1da177e4
LT		 297 goto free;
298 llc_conn_send_pdu(sk, nskb);
299 }
300out:
301 return rc;
302free:
303 kfree_skb(nskb);
304 goto out;
305}
306
307int llc_conn_ac_resend_frmr_rsp_f_set_0(struct sock *sk, struct sk_buff *skb)
308{
309 int rc = -ENOBUFS;
1d67e650 310 struct llc_sock *llc = llc_sk(sk);
f83f1768
JP		 311 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
312 sizeof(struct llc_frmr_info));
1da177e4
LT		 313
314 if (nskb) {
1da177e4
LT		 315 struct llc_sap *sap = llc->sap;
316 struct llc_pdu_sn *pdu = (struct llc_pdu_sn *)&llc->rx_pdu_hdr;
317
1da177e4
LT		 318 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
319 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 320 llc_pdu_init_as_frmr_rsp(nskb, pdu, 0, llc->vS,
1da177e4
LT		 321 llc->vR, INCORRECT);
322 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 323 if (unlikely(rc))
1da177e4
LT		 324 goto free;
325 llc_conn_send_pdu(sk, nskb);
326 }
327out:
328 return rc;
329free:
330 kfree_skb(nskb);
331 goto out;
332}
333
334int llc_conn_ac_resend_frmr_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
335{
336 u8 f_bit;
337 int rc = -ENOBUFS;
338 struct sk_buff *nskb;
1d67e650 339 struct llc_sock *llc = llc_sk(sk);
1da177e4
LT		 340
341 llc_pdu_decode_pf_bit(skb, &f_bit);
f83f1768
JP		 342 nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U,
343 sizeof(struct llc_frmr_info));
1da177e4 344 if (nskb) {
1da177e4
LT		 345 struct llc_sap *sap = llc->sap;
346 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
347
1da177e4
LT		 348 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
349 llc->daddr.lsap, LLC_PDU_RSP);
350 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
351 llc->vR, INCORRECT);
352 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 353 if (unlikely(rc))
1da177e4
LT		 354 goto free;
355 llc_conn_send_pdu(sk, nskb);
356 }
357out:
358 return rc;
359free:
360 kfree_skb(nskb);
361 goto out;
362}
363
364int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
365{
366 int rc;
367 struct llc_sock *llc = llc_sk(sk);
368 struct llc_sap *sap = llc->sap;
369
370 llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
371 llc->daddr.lsap, LLC_PDU_CMD);
372 llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR);
373 rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 374 if (likely(!rc)) {
b74555de 375 skb_get(skb);
1da177e4
LT		 376 llc_conn_send_pdu(sk, skb);
377 llc_conn_ac_inc_vs_by_1(sk, skb);
378 }
379 return rc;
380}
381
382static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb)
383{
384 int rc;
385 struct llc_sock *llc = llc_sk(sk);
386 struct llc_sap *sap = llc->sap;
387
388 llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
389 llc->daddr.lsap, LLC_PDU_CMD);
390 llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
391 rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 392 if (likely(!rc)) {
b74555de
EB		 393 skb_get(skb);
394 llc_conn_send_pdu(sk, skb);
1da177e4
LT		 395 llc_conn_ac_inc_vs_by_1(sk, skb);
396 }
397 return rc;
398}
399
400int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
401{
402 int rc;
403 struct llc_sock *llc = llc_sk(sk);
404 struct llc_sap *sap = llc->sap;
405
406 llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
407 llc->daddr.lsap, LLC_PDU_CMD);
408 llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
409 rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 410 if (likely(!rc)) {
b74555de 411 skb_get(skb);
1da177e4
LT		 412 llc_conn_send_pdu(sk, skb);
413 llc_conn_ac_inc_vs_by_1(sk, skb);
414 }
415 return 0;
416}
417
418int llc_conn_ac_resend_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
419{
420 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
421 u8 nr = LLC_I_GET_NR(pdu);
422
423 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
424 return 0;
425}
426
427int llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(struct sock *sk,
428 struct sk_buff *skb)
429{
430 u8 nr;
431 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
432 int rc = -ENOBUFS;
1d67e650 433 struct llc_sock *llc = llc_sk(sk);
f83f1768 434 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 435
436 if (nskb) {
1da177e4
LT		 437 struct llc_sap *sap = llc->sap;
438
1da177e4
LT		 439 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
440 llc->daddr.lsap, LLC_PDU_RSP);
441 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
442 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 443 if (likely(!rc))
1da177e4
LT		 444 llc_conn_send_pdu(sk, nskb);
445 else
446 kfree_skb(skb);
447 }
448 if (rc) {
449 nr = LLC_I_GET_NR(pdu);
450 rc = 0;
451 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
452 }
453 return rc;
454}
455
456int llc_conn_ac_resend_i_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
457{
458 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
459 u8 nr = LLC_I_GET_NR(pdu);
460
461 llc_conn_resend_i_pdu_as_rsp(sk, nr, 1);
462 return 0;
463}
464
465int llc_conn_ac_send_rej_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
466{
467 int rc = -ENOBUFS;
1d67e650 468 struct llc_sock *llc = llc_sk(sk);
f83f1768 469 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 470
471 if (nskb) {
1da177e4
LT		 472 struct llc_sap *sap = llc->sap;
473
1da177e4
LT		 474 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
475 llc->daddr.lsap, LLC_PDU_CMD);
476 llc_pdu_init_as_rej_cmd(nskb, 1, llc->vR);
477 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 478 if (unlikely(rc))
1da177e4
LT		 479 goto free;
480 llc_conn_send_pdu(sk, nskb);
481 }
482out:
483 return rc;
484free:
485 kfree_skb(nskb);
486 goto out;
487}
488
489int llc_conn_ac_send_rej_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
490{
491 int rc = -ENOBUFS;
1d67e650 492 struct llc_sock *llc = llc_sk(sk);
f83f1768 493 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 494
495 if (nskb) {
1da177e4
LT		 496 struct llc_sap *sap = llc->sap;
497
1da177e4
LT		 498 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
499 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 500 llc_pdu_init_as_rej_rsp(nskb, 1, llc->vR);
1da177e4 501 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 502 if (unlikely(rc))
1da177e4
LT		 503 goto free;
504 llc_conn_send_pdu(sk, nskb);
505 }
506out:
507 return rc;
508free:
509 kfree_skb(nskb);
510 goto out;
511}
512
513int llc_conn_ac_send_rej_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
514{
515 int rc = -ENOBUFS;
1d67e650 516 struct llc_sock *llc = llc_sk(sk);
f83f1768 517 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 518
519 if (nskb) {
1da177e4 520 struct llc_sap *sap = llc->sap;
1da177e4 521
1da177e4
LT		 522 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
523 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 524 llc_pdu_init_as_rej_rsp(nskb, 0, llc->vR);
1da177e4 525 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 526 if (unlikely(rc))
1da177e4
LT		 527 goto free;
528 llc_conn_send_pdu(sk, nskb);
529 }
530out:
531 return rc;
532free:
533 kfree_skb(nskb);
534 goto out;
535}
536
537int llc_conn_ac_send_rnr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
538{
539 int rc = -ENOBUFS;
1d67e650 540 struct llc_sock *llc = llc_sk(sk);
f83f1768 541 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 542
543 if (nskb) {
1da177e4
LT		 544 struct llc_sap *sap = llc->sap;
545
1da177e4
LT		 546 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
547 llc->daddr.lsap, LLC_PDU_CMD);
548 llc_pdu_init_as_rnr_cmd(nskb, 1, llc->vR);
549 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 550 if (unlikely(rc))
1da177e4
LT		 551 goto free;
552 llc_conn_send_pdu(sk, nskb);
553 }
554out:
555 return rc;
556free:
557 kfree_skb(nskb);
558 goto out;
559}
560
561int llc_conn_ac_send_rnr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
562{
563 int rc = -ENOBUFS;
1d67e650 564 struct llc_sock *llc = llc_sk(sk);
f83f1768 565 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 566
567 if (nskb) {
1da177e4 568 struct llc_sap *sap = llc->sap;
1da177e4 569
1da177e4
LT		 570 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
571 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 572 llc_pdu_init_as_rnr_rsp(nskb, 1, llc->vR);
1da177e4 573 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 574 if (unlikely(rc))
1da177e4
LT		 575 goto free;
576 llc_conn_send_pdu(sk, nskb);
577 }
578out:
579 return rc;
580free:
581 kfree_skb(nskb);
582 goto out;
583}
584
585int llc_conn_ac_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
586{
587 int rc = -ENOBUFS;
1d67e650 588 struct llc_sock *llc = llc_sk(sk);
f83f1768 589 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 590
591 if (nskb) {
1da177e4
LT		 592 struct llc_sap *sap = llc->sap;
593
1da177e4
LT		 594 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
595 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 596 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
1da177e4 597 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 598 if (unlikely(rc))
1da177e4
LT		 599 goto free;
600 llc_conn_send_pdu(sk, nskb);
601 }
602out:
603 return rc;
604free:
605 kfree_skb(nskb);
606 goto out;
607}
608
609int llc_conn_ac_set_remote_busy(struct sock *sk, struct sk_buff *skb)
610{
611 struct llc_sock *llc = llc_sk(sk);
612
613 if (!llc->remote_busy_flag) {
614 llc->remote_busy_flag = 1;
615 mod_timer(&llc->busy_state_timer.timer,
590232a7 616 jiffies + llc->busy_state_timer.expire);
1da177e4
LT		 617 }
618 return 0;
619}
620
621int llc_conn_ac_opt_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
622{
623 int rc = -ENOBUFS;
1d67e650 624 struct llc_sock *llc = llc_sk(sk);
f83f1768 625 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 626
627 if (nskb) {
1da177e4
LT		 628 struct llc_sap *sap = llc->sap;
629
1da177e4
LT		 630 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
631 llc->daddr.lsap, LLC_PDU_RSP);
632 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
633 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 634 if (unlikely(rc))
1da177e4
LT		 635 goto free;
636 llc_conn_send_pdu(sk, nskb);
637 }
638out:
639 return rc;
640free:
641 kfree_skb(nskb);
642 goto out;
643}
644
645int llc_conn_ac_send_rr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
646{
647 int rc = -ENOBUFS;
1d67e650 648 struct llc_sock *llc = llc_sk(sk);
f83f1768 649 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 650
651 if (nskb) {
1da177e4
LT		 652 struct llc_sap *sap = llc->sap;
653
1da177e4
LT		 654 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
655 llc->daddr.lsap, LLC_PDU_CMD);
656 llc_pdu_init_as_rr_cmd(nskb, 1, llc->vR);
657 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 658 if (unlikely(rc))
1da177e4
LT		 659 goto free;
660 llc_conn_send_pdu(sk, nskb);
661 }
662out:
663 return rc;
664free:
665 kfree_skb(nskb);
666 goto out;
667}
668
669int llc_conn_ac_send_rr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
670{
671 int rc = -ENOBUFS;
1d67e650 672 struct llc_sock *llc = llc_sk(sk);
f83f1768 673 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 674
675 if (nskb) {
1da177e4
LT		 676 struct llc_sap *sap = llc->sap;
677 u8 f_bit = 1;
678
1da177e4
LT		 679 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
680 llc->daddr.lsap, LLC_PDU_RSP);
681 llc_pdu_init_as_rr_rsp(nskb, f_bit, llc->vR);
682 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 683 if (unlikely(rc))
1da177e4
LT		 684 goto free;
685 llc_conn_send_pdu(sk, nskb);
686 }
687out:
688 return rc;
689free:
690 kfree_skb(nskb);
691 goto out;
692}
693
694int llc_conn_ac_send_ack_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
695{
696 int rc = -ENOBUFS;
1d67e650 697 struct llc_sock *llc = llc_sk(sk);
f83f1768 698 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 699
700 if (nskb) {
1da177e4 701 struct llc_sap *sap = llc->sap;
1da177e4 702
1da177e4
LT		 703 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
704 llc->daddr.lsap, LLC_PDU_RSP);
838a75da 705 llc_pdu_init_as_rr_rsp(nskb, 1, llc->vR);
1da177e4 706 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 707 if (unlikely(rc))
1da177e4
LT		 708 goto free;
709 llc_conn_send_pdu(sk, nskb);
710 }
711out:
712 return rc;
713free:
714 kfree_skb(nskb);
715 goto out;
716}
717
718int llc_conn_ac_send_rr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
719{
720 int rc = -ENOBUFS;
1d67e650 721 struct llc_sock *llc = llc_sk(sk);
f83f1768 722 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 723
724 if (nskb) {
1da177e4
LT		 725 struct llc_sap *sap = llc->sap;
726
1da177e4
LT		 727 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
728 llc->daddr.lsap, LLC_PDU_RSP);
729 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
730 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 731 if (unlikely(rc))
1da177e4
LT		 732 goto free;
733 llc_conn_send_pdu(sk, nskb);
734 }
735out:
736 return rc;
737free:
738 kfree_skb(nskb);
739 goto out;
740}
741
742int llc_conn_ac_send_ack_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
743{
744 int rc = -ENOBUFS;
1d67e650 745 struct llc_sock *llc = llc_sk(sk);
f83f1768 746 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 747
748 if (nskb) {
1da177e4
LT		 749 struct llc_sap *sap = llc->sap;
750
1da177e4
LT		 751 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
752 llc->daddr.lsap, LLC_PDU_RSP);
753 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
754 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 755 if (unlikely(rc))
1da177e4
LT		 756 goto free;
757 llc_conn_send_pdu(sk, nskb);
758 }
759out:
760 return rc;
761free:
762 kfree_skb(nskb);
763 goto out;
764}
765
766void llc_conn_set_p_flag(struct sock *sk, u8 value)
767{
768 int state_changed = llc_sk(sk)->p_flag && !value;
769
770 llc_sk(sk)->p_flag = value;
771
772 if (state_changed)
773 sk->sk_state_change(sk);
774}
775
776int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
777{
778 int rc = -ENOBUFS;
1da177e4 779 struct llc_sock *llc = llc_sk(sk);
f83f1768 780 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 781
782 if (nskb) {
783 struct llc_sap *sap = llc->sap;
2ef6db76 784 const u8 *dmac = llc->daddr.mac;
1da177e4
LT		 785
786 if (llc->dev->flags & IFF_LOOPBACK)
787 dmac = llc->dev->dev_addr;
1da177e4
LT		 788 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
789 llc->daddr.lsap, LLC_PDU_CMD);
790 llc_pdu_init_as_sabme_cmd(nskb, 1);
791 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, dmac);
249ff1c6 792 if (unlikely(rc))
1da177e4
LT		 793 goto free;
794 llc_conn_send_pdu(sk, nskb);
795 llc_conn_set_p_flag(sk, 1);
796 }
797out:
798 return rc;
799free:
800 kfree_skb(nskb);
801 goto out;
802}
803
804int llc_conn_ac_send_ua_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
805{
806 u8 f_bit;
807 int rc = -ENOBUFS;
1d67e650 808 struct llc_sock *llc = llc_sk(sk);
f83f1768 809 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_U, 0);
1da177e4
LT		 810
811 llc_pdu_decode_pf_bit(skb, &f_bit);
812 if (nskb) {
1da177e4
LT		 813 struct llc_sap *sap = llc->sap;
814
815 nskb->dev = llc->dev;
816 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
817 llc->daddr.lsap, LLC_PDU_RSP);
818 llc_pdu_init_as_ua_rsp(nskb, f_bit);
819 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 820 if (unlikely(rc))
1da177e4
LT		 821 goto free;
822 llc_conn_send_pdu(sk, nskb);
823 }
824out:
825 return rc;
826free:
827 kfree_skb(nskb);
828 goto out;
829}
830
831int llc_conn_ac_set_s_flag_0(struct sock *sk, struct sk_buff *skb)
832{
833 llc_sk(sk)->s_flag = 0;
834 return 0;
835}
836
837int llc_conn_ac_set_s_flag_1(struct sock *sk, struct sk_buff *skb)
838{
839 llc_sk(sk)->s_flag = 1;
840 return 0;
841}
842
843int llc_conn_ac_start_p_timer(struct sock *sk, struct sk_buff *skb)
844{
845 struct llc_sock *llc = llc_sk(sk);
846
847 llc_conn_set_p_flag(sk, 1);
848 mod_timer(&llc->pf_cycle_timer.timer,
590232a7 849 jiffies + llc->pf_cycle_timer.expire);
1da177e4
LT		 850 return 0;
851}
852
853/**
854 * llc_conn_ac_send_ack_if_needed - check if ack is needed
855 * @sk: current connection structure
856 * @skb: current event
857 *
858 * Checks number of received PDUs which have not been acknowledged, yet,
859 * If number of them reaches to "npta"(Number of PDUs To Acknowledge) then
860 * sends an RR response as acknowledgement for them. Returns 0 for
861 * success, 1 otherwise.
862 */
863int llc_conn_ac_send_ack_if_needed(struct sock *sk, struct sk_buff *skb)
864{
865 u8 pf_bit;
866 struct llc_sock *llc = llc_sk(sk);
867
868 llc_pdu_decode_pf_bit(skb, &pf_bit);
869 llc->ack_pf |= pf_bit & 1;
870 if (!llc->ack_must_be_send) {
871 llc->first_pdu_Ns = llc->vR;
872 llc->ack_must_be_send = 1;
873 llc->ack_pf = pf_bit & 1;
874 }
59c6196e
JF		 875 if (((llc->vR - llc->first_pdu_Ns + 1 + LLC_2_SEQ_NBR_MODULO)
876 % LLC_2_SEQ_NBR_MODULO) >= llc->npta) {
1da177e4
LT		 877 llc_conn_ac_send_rr_rsp_f_set_ackpf(sk, skb);
878 llc->ack_must_be_send = 0;
879 llc->ack_pf = 0;
880 llc_conn_ac_inc_npta_value(sk, skb);
881 }
882 return 0;
883}
884
885/**
886 * llc_conn_ac_rst_sendack_flag - resets ack_must_be_send flag
887 * @sk: current connection structure
888 * @skb: current event
889 *
890 * This action resets ack_must_be_send flag of given connection, this flag
891 * indicates if there is any PDU which has not been acknowledged yet.
892 * Returns 0 for success, 1 otherwise.
893 */
894int llc_conn_ac_rst_sendack_flag(struct sock *sk, struct sk_buff *skb)
895{
896 llc_sk(sk)->ack_must_be_send = llc_sk(sk)->ack_pf = 0;
897 return 0;
898}
899
900/**
901 * llc_conn_ac_send_i_rsp_f_set_ackpf - acknowledge received PDUs
902 * @sk: current connection structure
903 * @skb: current event
904 *
905 * Sends an I response PDU with f-bit set to ack_pf flag as acknowledge to
906 * all received PDUs which have not been acknowledged, yet. ack_pf flag is
907 * set to one if one PDU with p-bit set to one is received. Returns 0 for
908 * success, 1 otherwise.
909 */
910static int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk,
911 struct sk_buff *skb)
912{
913 int rc;
914 struct llc_sock *llc = llc_sk(sk);
915 struct llc_sap *sap = llc->sap;
916
917 llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
918 llc->daddr.lsap, LLC_PDU_RSP);
919 llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR);
920 rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 921 if (likely(!rc)) {
b74555de
EB		 922 skb_get(skb);
923 llc_conn_send_pdu(sk, skb);
1da177e4
LT		 924 llc_conn_ac_inc_vs_by_1(sk, skb);
925 }
926 return rc;
927}
928
929/**
930 * llc_conn_ac_send_i_as_ack - sends an I-format PDU to acknowledge rx PDUs
931 * @sk: current connection structure.
932 * @skb: current event.
933 *
934 * This action sends an I-format PDU as acknowledge to received PDUs which
935 * have not been acknowledged, yet, if there is any. By using of this
936 * action number of acknowledgements decreases, this technic is called
937 * piggy backing. Returns 0 for success, 1 otherwise.
938 */
939int llc_conn_ac_send_i_as_ack(struct sock *sk, struct sk_buff *skb)
940{
941 struct llc_sock *llc = llc_sk(sk);
b85ab56c 942 int ret;
1da177e4
LT		 943
944 if (llc->ack_must_be_send) {
b85ab56c 945 ret = llc_conn_ac_send_i_rsp_f_set_ackpf(sk, skb);
1da177e4
LT		 946 llc->ack_must_be_send = 0 ;
947 llc->ack_pf = 0;
b85ab56c
CW		 948 } else {
949 ret = llc_conn_ac_send_i_cmd_p_set_0(sk, skb);
950 }
951
952 return ret;
1da177e4
LT		 953}
954
955/**
956 * llc_conn_ac_send_rr_rsp_f_set_ackpf - ack all rx PDUs not yet acked
957 * @sk: current connection structure.
958 * @skb: current event.
959 *
960 * This action sends an RR response with f-bit set to ack_pf flag as
961 * acknowledge to all received PDUs which have not been acknowledged, yet,
962 * if there is any. ack_pf flag indicates if a PDU has been received with
963 * p-bit set to one. Returns 0 for success, 1 otherwise.
964 */
965static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
966 struct sk_buff *skb)
967{
968 int rc = -ENOBUFS;
1d67e650 969 struct llc_sock *llc = llc_sk(sk);
f83f1768 970 struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev, LLC_PDU_TYPE_S, 0);
1da177e4
LT		 971
972 if (nskb) {
1da177e4
LT		 973 struct llc_sap *sap = llc->sap;
974
1da177e4
LT		 975 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
976 llc->daddr.lsap, LLC_PDU_RSP);
977 llc_pdu_init_as_rr_rsp(nskb, llc->ack_pf, llc->vR);
978 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
249ff1c6 979 if (unlikely(rc))
1da177e4
LT		 980 goto free;
981 llc_conn_send_pdu(sk, nskb);
982 }
983out:
984 return rc;
985free:
986 kfree_skb(nskb);
987 goto out;
988}
989
990/**
991 * llc_conn_ac_inc_npta_value - tries to make value of npta greater
992 * @sk: current connection structure.
993 * @skb: current event.
994 *
995 * After "inc_cntr" times calling of this action, "npta" increase by one.
996 * this action tries to make vale of "npta" greater as possible; number of
997 * acknowledgements decreases by increasing of "npta". Returns 0 for
998 * success, 1 otherwise.
999 */
1000static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb)
1001{
1002 struct llc_sock *llc = llc_sk(sk);
1003
1004 if (!llc->inc_cntr) {
1005 llc->dec_step = 0;
1006 llc->dec_cntr = llc->inc_cntr = 2;
1007 ++llc->npta;
38199824
DM		 1008 if (llc->npta > (u8) ~LLC_2_SEQ_NBR_MODULO)
1009 llc->npta = (u8) ~LLC_2_SEQ_NBR_MODULO;
1da177e4
LT		 1010 } else
1011 --llc->inc_cntr;
1012 return 0;
1013}
1014
1015/**
1016 * llc_conn_ac_adjust_npta_by_rr - decreases "npta" by one
1017 * @sk: current connection structure.
1018 * @skb: current event.
1019 *
1020 * After receiving "dec_cntr" times RR command, this action decreases
1021 * "npta" by one. Returns 0 for success, 1 otherwise.
1022 */
1023int llc_conn_ac_adjust_npta_by_rr(struct sock *sk, struct sk_buff *skb)
1024{
1025 struct llc_sock *llc = llc_sk(sk);
1026
1027 if (!llc->connect_step && !llc->remote_busy_flag) {
1028 if (!llc->dec_step) {
1029 if (!llc->dec_cntr) {
1030 llc->inc_cntr = llc->dec_cntr = 2;
1031 if (llc->npta > 0)
1032 llc->npta = llc->npta - 1;
1033 } else
1034 llc->dec_cntr -=1;
1035 }
1036 } else
1037 llc->connect_step = 0 ;
1038 return 0;
1039}
1040
1041/**
1042 * llc_conn_ac_adjust_npta_by_rnr - decreases "npta" by one
1043 * @sk: current connection structure.
1044 * @skb: current event.
1045 *
1046 * After receiving "dec_cntr" times RNR command, this action decreases
1047 * "npta" by one. Returns 0 for success, 1 otherwise.
1048 */
1049int llc_conn_ac_adjust_npta_by_rnr(struct sock *sk, struct sk_buff *skb)
1050{
1051 struct llc_sock *llc = llc_sk(sk);
1052
1053 if (llc->remote_busy_flag)
1054 if (!llc->dec_step) {
1055 if (!llc->dec_cntr) {
1056 llc->inc_cntr = llc->dec_cntr = 2;
1057 if (llc->npta > 0)
1058 --llc->npta;
1059 } else
1060 --llc->dec_cntr;
1061 }
1062 return 0;
1063}
1064
1065/**
1066 * llc_conn_ac_dec_tx_win_size - decreases tx window size
1067 * @sk: current connection structure.
1068 * @skb: current event.
1069 *
1070 * After receiving of a REJ command or response, transmit window size is
1071 * decreased by number of PDUs which are outstanding yet. Returns 0 for
1072 * success, 1 otherwise.
1073 */
1074int llc_conn_ac_dec_tx_win_size(struct sock *sk, struct sk_buff *skb)
1075{
1076 struct llc_sock *llc = llc_sk(sk);
1077 u8 unacked_pdu = skb_queue_len(&llc->pdu_unack_q);
1078
59c6196e
JF		 1079 if (llc->k - unacked_pdu < 1)
1080 llc->k = 1;
1081 else
1082 llc->k -= unacked_pdu;
1da177e4
LT		 1083 return 0;
1084}
1085
1086/**
1087 * llc_conn_ac_inc_tx_win_size - tx window size is inc by 1
1088 * @sk: current connection structure.
1089 * @skb: current event.
1090 *
1091 * After receiving an RR response with f-bit set to one, transmit window
1092 * size is increased by one. Returns 0 for success, 1 otherwise.
1093 */
1094int llc_conn_ac_inc_tx_win_size(struct sock *sk, struct sk_buff *skb)
1095{
1096 struct llc_sock *llc = llc_sk(sk);
1097
1098 llc->k += 1;
38199824
DM		 1099 if (llc->k > (u8) ~LLC_2_SEQ_NBR_MODULO)
1100 llc->k = (u8) ~LLC_2_SEQ_NBR_MODULO;
1da177e4
LT		 1101 return 0;
1102}
1103
1104int llc_conn_ac_stop_all_timers(struct sock *sk, struct sk_buff *skb)
1105{
b905ef9a 1106 llc_sk_stop_all_timers(sk, false);
1da177e4
LT		 1107 return 0;
1108}
1109
1110int llc_conn_ac_stop_other_timers(struct sock *sk, struct sk_buff *skb)
1111{
1112 struct llc_sock *llc = llc_sk(sk);
1113
1114 del_timer(&llc->rej_sent_timer.timer);
1115 del_timer(&llc->pf_cycle_timer.timer);
1116 del_timer(&llc->busy_state_timer.timer);
1117 llc->ack_must_be_send = 0;
1118 llc->ack_pf = 0;
1119 return 0;
1120}
1121
1122int llc_conn_ac_start_ack_timer(struct sock *sk, struct sk_buff *skb)
1123{
1124 struct llc_sock *llc = llc_sk(sk);
1125
590232a7 1126 mod_timer(&llc->ack_timer.timer, jiffies + llc->ack_timer.expire);
1da177e4
LT		 1127 return 0;
1128}
1129
1130int llc_conn_ac_start_rej_timer(struct sock *sk, struct sk_buff *skb)
1131{
1132 struct llc_sock *llc = llc_sk(sk);
1133
1134 mod_timer(&llc->rej_sent_timer.timer,
590232a7 1135 jiffies + llc->rej_sent_timer.expire);
1da177e4
LT		 1136 return 0;
1137}
1138
1139int llc_conn_ac_start_ack_tmr_if_not_running(struct sock *sk,
1140 struct sk_buff *skb)
1141{
1142 struct llc_sock *llc = llc_sk(sk);
1143
1144 if (!timer_pending(&llc->ack_timer.timer))
1145 mod_timer(&llc->ack_timer.timer,
590232a7 1146 jiffies + llc->ack_timer.expire);
1da177e4
LT		 1147 return 0;
1148}
1149
1150int llc_conn_ac_stop_ack_timer(struct sock *sk, struct sk_buff *skb)
1151{
1152 del_timer(&llc_sk(sk)->ack_timer.timer);
1153 return 0;
1154}
1155
1156int llc_conn_ac_stop_p_timer(struct sock *sk, struct sk_buff *skb)
1157{
1158 struct llc_sock *llc = llc_sk(sk);
1159
1160 del_timer(&llc->pf_cycle_timer.timer);
1161 llc_conn_set_p_flag(sk, 0);
1162 return 0;
1163}
1164
1165int llc_conn_ac_stop_rej_timer(struct sock *sk, struct sk_buff *skb)
1166{
1167 del_timer(&llc_sk(sk)->rej_sent_timer.timer);
1168 return 0;
1169}
1170
1171int llc_conn_ac_upd_nr_received(struct sock *sk, struct sk_buff *skb)
1172{
1173 int acked;
1174 u16 unacked = 0;
1175 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1176 struct llc_sock *llc = llc_sk(sk);
1177
1178 llc->last_nr = PDU_SUPV_GET_Nr(pdu);
1179 acked = llc_conn_remove_acked_pdus(sk, llc->last_nr, &unacked);
1180 /* On loopback we don't queue I frames in unack_pdu_q queue. */
1181 if (acked > 0 || (llc->dev->flags & IFF_LOOPBACK)) {
1182 llc->retry_count = 0;
1183 del_timer(&llc->ack_timer.timer);
1184 if (llc->failed_data_req) {
1185 /* already, we did not accept data from upper layer
1186 * (tx_window full or unacceptable state). Now, we
1187 * can send data and must inform to upper layer.
1188 */
1189 llc->failed_data_req = 0;
1190 llc_conn_ac_data_confirm(sk, skb);
1191 }
1192 if (unacked)
1193 mod_timer(&llc->ack_timer.timer,
590232a7 1194 jiffies + llc->ack_timer.expire);
1da177e4
LT		 1195 } else if (llc->failed_data_req) {
1196 u8 f_bit;
1197
1198 llc_pdu_decode_pf_bit(skb, &f_bit);
1199 if (f_bit == 1) {
1200 llc->failed_data_req = 0;
1201 llc_conn_ac_data_confirm(sk, skb);
1202 }
1203 }
1204 return 0;
1205}
1206
1207int llc_conn_ac_upd_p_flag(struct sock *sk, struct sk_buff *skb)
1208{
1209 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1210
1211 if (LLC_PDU_IS_RSP(pdu)) {
1212 u8 f_bit;
1213
1214 llc_pdu_decode_pf_bit(skb, &f_bit);
1215 if (f_bit) {
1216 llc_conn_set_p_flag(sk, 0);
1217 llc_conn_ac_stop_p_timer(sk, skb);
1218 }
1219 }
1220 return 0;
1221}
1222
1223int llc_conn_ac_set_data_flag_2(struct sock *sk, struct sk_buff *skb)
1224{
1225 llc_sk(sk)->data_flag = 2;
1226 return 0;
1227}
1228
1229int llc_conn_ac_set_data_flag_0(struct sock *sk, struct sk_buff *skb)
1230{
1231 llc_sk(sk)->data_flag = 0;
1232 return 0;
1233}
1234
1235int llc_conn_ac_set_data_flag_1(struct sock *sk, struct sk_buff *skb)
1236{
1237 llc_sk(sk)->data_flag = 1;
1238 return 0;
1239}
1240
1241int llc_conn_ac_set_data_flag_1_if_data_flag_eq_0(struct sock *sk,
1242 struct sk_buff *skb)
1243{
1244 if (!llc_sk(sk)->data_flag)
1245 llc_sk(sk)->data_flag = 1;
1246 return 0;
1247}
1248
1249int llc_conn_ac_set_p_flag_0(struct sock *sk, struct sk_buff *skb)
1250{
1251 llc_conn_set_p_flag(sk, 0);
1252 return 0;
1253}
1254
1255static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb)
1256{
1257 llc_conn_set_p_flag(sk, 1);
1258 return 0;
1259}
1260
1261int llc_conn_ac_set_remote_busy_0(struct sock *sk, struct sk_buff *skb)
1262{
1263 llc_sk(sk)->remote_busy_flag = 0;
1264 return 0;
1265}
1266
1267int llc_conn_ac_set_cause_flag_0(struct sock *sk, struct sk_buff *skb)
1268{
1269 llc_sk(sk)->cause_flag = 0;
1270 return 0;
1271}
1272
1273int llc_conn_ac_set_cause_flag_1(struct sock *sk, struct sk_buff *skb)
1274{
1275 llc_sk(sk)->cause_flag = 1;
1276 return 0;
1277}
1278
1279int llc_conn_ac_set_retry_cnt_0(struct sock *sk, struct sk_buff *skb)
1280{
1281 llc_sk(sk)->retry_count = 0;
1282 return 0;
1283}
1284
1285int llc_conn_ac_inc_retry_cnt_by_1(struct sock *sk, struct sk_buff *skb)
1286{
1287 llc_sk(sk)->retry_count++;
1288 return 0;
1289}
1290
1291int llc_conn_ac_set_vr_0(struct sock *sk, struct sk_buff *skb)
1292{
1293 llc_sk(sk)->vR = 0;
1294 return 0;
1295}
1296
1297int llc_conn_ac_inc_vr_by_1(struct sock *sk, struct sk_buff *skb)
1298{
1299 llc_sk(sk)->vR = PDU_GET_NEXT_Vr(llc_sk(sk)->vR);
1300 return 0;
1301}
1302
1303int llc_conn_ac_set_vs_0(struct sock *sk, struct sk_buff *skb)
1304{
1305 llc_sk(sk)->vS = 0;
1306 return 0;
1307}
1308
1309int llc_conn_ac_set_vs_nr(struct sock *sk, struct sk_buff *skb)
1310{
1311 llc_sk(sk)->vS = llc_sk(sk)->last_nr;
1312 return 0;
1313}
1314
2928c19e 1315static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb)
1da177e4 1316{
59c6196e 1317 llc_sk(sk)->vS = (llc_sk(sk)->vS + 1) % LLC_2_SEQ_NBR_MODULO;
1da177e4
LT		 1318 return 0;
1319}
1320
fc8bcaa0 1321static void llc_conn_tmr_common_cb(struct sock *sk, u8 type)
1da177e4 1322{
1da177e4
LT		 1323 struct sk_buff *skb = alloc_skb(0, GFP_ATOMIC);
1324
1325 bh_lock_sock(sk);
1326 if (skb) {
1327 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
1328
04e4223f 1329 skb_set_owner_r(skb, sk);
e0dd5519 1330 ev->type = type;
1da177e4
LT		 1331 llc_process_tmr_ev(sk, skb);
1332 }
1333 bh_unlock_sock(sk);
1334}
1335
fc8bcaa0 1336void llc_conn_pf_cycle_tmr_cb(struct timer_list *t)
1da177e4 1337{
fc8bcaa0
KC		 1338 struct llc_sock *llc = from_timer(llc, t, pf_cycle_timer.timer);
1339
1340 llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_P_TMR);
e0dd5519 1341}
1da177e4 1342
fc8bcaa0 1343void llc_conn_busy_tmr_cb(struct timer_list *t)
e0dd5519 1344{
fc8bcaa0
KC		 1345 struct llc_sock *llc = from_timer(llc, t, busy_state_timer.timer);
1346
1347 llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_BUSY_TMR);
1da177e4
LT		 1348}
1349
fc8bcaa0 1350void llc_conn_ack_tmr_cb(struct timer_list *t)
1da177e4 1351{
fc8bcaa0
KC		 1352 struct llc_sock *llc = from_timer(llc, t, ack_timer.timer);
1353
1354 llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_ACK_TMR);
1da177e4
LT		 1355}
1356
fc8bcaa0 1357void llc_conn_rej_tmr_cb(struct timer_list *t)
1da177e4 1358{
fc8bcaa0
KC		 1359 struct llc_sock *llc = from_timer(llc, t, rej_sent_timer.timer);
1360
1361 llc_conn_tmr_common_cb(&llc->sk, LLC_CONN_EV_TYPE_REJ_TMR);
1da177e4
LT		 1362}
1363
1364int llc_conn_ac_rst_vs(struct sock *sk, struct sk_buff *skb)
1365{
1366 llc_sk(sk)->X = llc_sk(sk)->vS;
1367 llc_conn_ac_set_vs_nr(sk, skb);
1368 return 0;
1369}
1370
1371int llc_conn_ac_upd_vs(struct sock *sk, struct sk_buff *skb)
1372{
1373 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1374 u8 nr = PDU_SUPV_GET_Nr(pdu);
1375
1376 if (llc_circular_between(llc_sk(sk)->vS, nr, llc_sk(sk)->X))
1377 llc_conn_ac_set_vs_nr(sk, skb);
1378 return 0;
1379}
1380
1381/*
1382 * Non-standard actions; these not contained in IEEE specification; for
1383 * our own usage
1384 */
1385/**
1386 * llc_conn_disc - removes connection from SAP list and frees it
1387 * @sk: closed connection
1388 * @skb: occurred event
1389 */
1390int llc_conn_disc(struct sock *sk, struct sk_buff *skb)
1391{
1392 /* FIXME: this thing seems to want to die */
1393 return 0;
1394}
1395
1396/**
1397 * llc_conn_reset - resets connection
1398 * @sk : reseting connection.
1399 * @skb: occurred event.
1400 *
1401 * Stop all timers, empty all queues and reset all flags.
1402 */
1403int llc_conn_reset(struct sock *sk, struct sk_buff *skb)
1404{
1405 llc_sk_reset(sk);
1406 return 0;
1407}
1408
1409/**
1410 * llc_circular_between - designates that b is between a and c or not
1411 * @a: lower bound
1412 * @b: element to see if is between a and b
1413 * @c: upper bound
1414 *
1415 * This function designates that b is between a and c or not (for example,
1416 * 0 is between 127 and 1). Returns 1 if b is between a and c, 0
1417 * otherwise.
1418 */
1419u8 llc_circular_between(u8 a, u8 b, u8 c)
1420{
1421 b = b - a;
1422 c = c - a;
1423 return b <= c;
1424}
1425
1426/**
1427 * llc_process_tmr_ev - timer backend
1428 * @sk: active connection
1429 * @skb: occurred event
1430 *
1431 * This function is called from timer callback functions. When connection
1432 * is busy (during sending a data frame) timer expiration event must be
1433 * queued. Otherwise this event can be sent to connection state machine.
1434 * Queued events will process by llc_backlog_rcv function after sending
1435 * data frame.
1436 */
1437static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb)
1438{
1439 if (llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC) {
1440 printk(KERN_WARNING "%s: timer called on closed connection\n",
0dc47877 1441 __func__);
1da177e4
LT		 1442 kfree_skb(skb);
1443 } else {
1444 if (!sock_owned_by_user(sk))
1445 llc_conn_state_process(sk, skb);
1446 else {
1447 llc_set_backlog_type(skb, LLC_EVENT);
a3a858ff 1448 __sk_add_backlog(sk, skb);
1da177e4
LT		 1449 }
1450 }
1451}
Linux 6.x block layer and io_uring tree(s)