[LLC]: Fix the accept path
[linux-3.10.git] / net / llc / llc_c_ac.c
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>
21 #include <net/llc_conn.h>
22 #include <net/llc_sap.h>
23 #include <net/sock.h>
24 #include <net/llc_c_ev.h>
25 #include <net/llc_c_ac.h>
26 #include <net/llc_c_st.h>
27 #include <net/llc_pdu.h>
28 #include <net/llc.h>
29
30 #include "llc_output.h"
31
32 static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb);
33 static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb);
34 static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *ev);
35
36 static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb);
37
38 static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
39                                                struct sk_buff *skb);
40
41 static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb);
42
43 #define INCORRECT 0
44
45 int 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
61 int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
62 {
63         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
64
65         ev->ind_prim = LLC_CONN_PRIM;
66         return 0;
67 }
68
69 int 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
77 static 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
85 int 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
91 int 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;
110         else
111                 rc = -EINVAL;
112         if (!rc) {
113                 ev->reason   = reason;
114                 ev->ind_prim = LLC_DISC_PRIM;
115         }
116         return rc;
117 }
118
119 int 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
128 int 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;
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;
157                 }
158                 break;
159         }
160         if (!rc) {
161                 ev->reason   = reason;
162                 ev->ind_prim = LLC_RESET_PRIM;
163         }
164         return rc;
165 }
166
167 int 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
176 int 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
188 int 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
198 int llc_conn_ac_send_disc_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
199 {
200         int rc = -ENOBUFS;
201         struct llc_sock *llc = llc_sk(sk);
202         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
203
204         if (nskb) {
205                 struct llc_sap *sap = llc->sap;
206
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);
211                 if (unlikely(rc))
212                         goto free;
213                 llc_conn_send_pdu(sk, nskb);
214                 llc_conn_ac_set_p_flag_1(sk, skb);
215         }
216 out:
217         return rc;
218 free:
219         kfree_skb(nskb);
220         goto out;
221 }
222
223 int llc_conn_ac_send_dm_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
224 {
225         int rc = -ENOBUFS;
226         struct llc_sock *llc = llc_sk(sk);
227         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
228
229         if (nskb) {
230                 struct llc_sap *sap = llc->sap;
231                 u8 f_bit;
232
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);
238                 if (unlikely(rc))
239                         goto free;
240                 llc_conn_send_pdu(sk, nskb);
241         }
242 out:
243         return rc;
244 free:
245         kfree_skb(nskb);
246         goto out;
247 }
248
249 int llc_conn_ac_send_dm_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
250 {
251         int rc = -ENOBUFS;
252         struct llc_sock *llc = llc_sk(sk);
253         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
254
255         if (nskb) {
256                 struct llc_sap *sap = llc->sap;
257
258                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
259                                     llc->daddr.lsap, LLC_PDU_RSP);
260                 llc_pdu_init_as_dm_rsp(nskb, 1);
261                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
262                 if (unlikely(rc))
263                         goto free;
264                 llc_conn_send_pdu(sk, nskb);
265         }
266 out:
267         return rc;
268 free:
269         kfree_skb(nskb);
270         goto out;
271 }
272
273 int 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;
286         nskb = llc_alloc_frame(sk, llc->dev);
287         if (nskb) {
288                 struct llc_sap *sap = llc->sap;
289
290                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
291                                     llc->daddr.lsap, LLC_PDU_RSP);
292                 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
293                                          llc->vR, INCORRECT);
294                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
295                 if (unlikely(rc))
296                         goto free;
297                 llc_conn_send_pdu(sk, nskb);
298         }
299 out:
300         return rc;
301 free:
302         kfree_skb(nskb);
303         goto out;
304 }
305
306 int llc_conn_ac_resend_frmr_rsp_f_set_0(struct sock *sk, struct sk_buff *skb)
307 {
308         int rc = -ENOBUFS;
309         struct llc_sock *llc = llc_sk(sk);
310         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
311
312         if (nskb) {
313                 struct llc_sap *sap = llc->sap;
314                 struct llc_pdu_sn *pdu = (struct llc_pdu_sn *)&llc->rx_pdu_hdr;
315
316                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
317                                     llc->daddr.lsap, LLC_PDU_RSP);
318                 llc_pdu_init_as_frmr_rsp(nskb, pdu, 0, llc->vS,
319                                          llc->vR, INCORRECT);
320                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
321                 if (unlikely(rc))
322                         goto free;
323                 llc_conn_send_pdu(sk, nskb);
324         }
325 out:
326         return rc;
327 free:
328         kfree_skb(nskb);
329         goto out;
330 }
331
332 int llc_conn_ac_resend_frmr_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
333 {
334         u8 f_bit;
335         int rc = -ENOBUFS;
336         struct sk_buff *nskb;
337         struct llc_sock *llc = llc_sk(sk);
338
339         llc_pdu_decode_pf_bit(skb, &f_bit);
340         nskb = llc_alloc_frame(sk, llc->dev);
341         if (nskb) {
342                 struct llc_sap *sap = llc->sap;
343                 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
344
345                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
346                                     llc->daddr.lsap, LLC_PDU_RSP);
347                 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
348                                          llc->vR, INCORRECT);
349                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
350                 if (unlikely(rc))
351                         goto free;
352                 llc_conn_send_pdu(sk, nskb);
353         }
354 out:
355         return rc;
356 free:
357         kfree_skb(nskb);
358         goto out;
359 }
360
361 int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
362 {
363         int rc;
364         struct llc_sock *llc = llc_sk(sk);
365         struct llc_sap *sap = llc->sap;
366
367         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
368                             llc->daddr.lsap, LLC_PDU_CMD);
369         llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR);
370         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
371         if (likely(!rc)) {
372                 llc_conn_send_pdu(sk, skb);
373                 llc_conn_ac_inc_vs_by_1(sk, skb);
374         }
375         return rc;
376 }
377
378 static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb)
379 {
380         int rc;
381         struct llc_sock *llc = llc_sk(sk);
382         struct llc_sap *sap = llc->sap;
383
384         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
385                             llc->daddr.lsap, LLC_PDU_CMD);
386         llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
387         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
388         if (likely(!rc)) {
389                 llc_conn_send_pdu(sk, skb);
390                 llc_conn_ac_inc_vs_by_1(sk, skb);
391         }
392         return rc;
393 }
394
395 int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
396 {
397         int rc;
398         struct llc_sock *llc = llc_sk(sk);
399         struct llc_sap *sap = llc->sap;
400
401         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
402                             llc->daddr.lsap, LLC_PDU_CMD);
403         llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
404         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
405         if (likely(!rc)) {
406                 llc_conn_send_pdu(sk, skb);
407                 llc_conn_ac_inc_vs_by_1(sk, skb);
408         }
409         return 0;
410 }
411
412 int llc_conn_ac_resend_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
413 {
414         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
415         u8 nr = LLC_I_GET_NR(pdu);
416
417         llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
418         return 0;
419 }
420
421 int llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(struct sock *sk,
422                                                 struct sk_buff *skb)
423 {
424         u8 nr;
425         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
426         int rc = -ENOBUFS;
427         struct llc_sock *llc = llc_sk(sk);
428         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
429
430         if (nskb) {
431                 struct llc_sap *sap = llc->sap;
432
433                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
434                                     llc->daddr.lsap, LLC_PDU_RSP);
435                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
436                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
437                 if (likely(!rc))
438                         llc_conn_send_pdu(sk, nskb);
439                 else
440                         kfree_skb(skb);
441         }
442         if (rc) {
443                 nr = LLC_I_GET_NR(pdu);
444                 rc = 0;
445                 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
446         }
447         return rc;
448 }
449
450 int llc_conn_ac_resend_i_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
451 {
452         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
453         u8 nr = LLC_I_GET_NR(pdu);
454
455         llc_conn_resend_i_pdu_as_rsp(sk, nr, 1);
456         return 0;
457 }
458
459 int llc_conn_ac_send_rej_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
460 {
461         int rc = -ENOBUFS;
462         struct llc_sock *llc = llc_sk(sk);
463         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
464
465         if (nskb) {
466                 struct llc_sap *sap = llc->sap;
467
468                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
469                                     llc->daddr.lsap, LLC_PDU_CMD);
470                 llc_pdu_init_as_rej_cmd(nskb, 1, llc->vR);
471                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
472                 if (unlikely(rc))
473                         goto free;
474                 llc_conn_send_pdu(sk, nskb);
475         }
476 out:
477         return rc;
478 free:
479         kfree_skb(nskb);
480         goto out;
481 }
482
483 int llc_conn_ac_send_rej_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
484 {
485         int rc = -ENOBUFS;
486         struct llc_sock *llc = llc_sk(sk);
487         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
488
489         if (nskb) {
490                 struct llc_sap *sap = llc->sap;
491
492                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
493                                     llc->daddr.lsap, LLC_PDU_RSP);
494                 llc_pdu_init_as_rej_rsp(nskb, 1, llc->vR);
495                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
496                 if (unlikely(rc))
497                         goto free;
498                 llc_conn_send_pdu(sk, nskb);
499         }
500 out:
501         return rc;
502 free:
503         kfree_skb(nskb);
504         goto out;
505 }
506
507 int llc_conn_ac_send_rej_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
508 {
509         int rc = -ENOBUFS;
510         struct llc_sock *llc = llc_sk(sk);
511         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
512
513         if (nskb) {
514                 struct llc_sap *sap = llc->sap;
515
516                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
517                                     llc->daddr.lsap, LLC_PDU_RSP);
518                 llc_pdu_init_as_rej_rsp(nskb, 0, llc->vR);
519                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
520                 if (unlikely(rc))
521                         goto free;
522                 llc_conn_send_pdu(sk, nskb);
523         }
524 out:
525         return rc;
526 free:
527         kfree_skb(nskb);
528         goto out;
529 }
530
531 int llc_conn_ac_send_rnr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
532 {
533         int rc = -ENOBUFS;
534         struct llc_sock *llc = llc_sk(sk);
535         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
536
537         if (nskb) {
538                 struct llc_sap *sap = llc->sap;
539
540                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
541                                     llc->daddr.lsap, LLC_PDU_CMD);
542                 llc_pdu_init_as_rnr_cmd(nskb, 1, llc->vR);
543                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
544                 if (unlikely(rc))
545                         goto free;
546                 llc_conn_send_pdu(sk, nskb);
547         }
548 out:
549         return rc;
550 free:
551         kfree_skb(nskb);
552         goto out;
553 }
554
555 int llc_conn_ac_send_rnr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
556 {
557         int rc = -ENOBUFS;
558         struct llc_sock *llc = llc_sk(sk);
559         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
560
561         if (nskb) {
562                 struct llc_sap *sap = llc->sap;
563
564                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
565                                     llc->daddr.lsap, LLC_PDU_RSP);
566                 llc_pdu_init_as_rnr_rsp(nskb, 1, llc->vR);
567                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
568                 if (unlikely(rc))
569                         goto free;
570                 llc_conn_send_pdu(sk, nskb);
571         }
572 out:
573         return rc;
574 free:
575         kfree_skb(nskb);
576         goto out;
577 }
578
579 int llc_conn_ac_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
580 {
581         int rc = -ENOBUFS;
582         struct llc_sock *llc = llc_sk(sk);
583         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
584
585         if (nskb) {
586                 struct llc_sap *sap = llc->sap;
587
588                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
589                                     llc->daddr.lsap, LLC_PDU_RSP);
590                 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
591                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
592                 if (unlikely(rc))
593                         goto free;
594                 llc_conn_send_pdu(sk, nskb);
595         }
596 out:
597         return rc;
598 free:
599         kfree_skb(nskb);
600         goto out;
601 }
602
603 int llc_conn_ac_set_remote_busy(struct sock *sk, struct sk_buff *skb)
604 {
605         struct llc_sock *llc = llc_sk(sk);
606
607         if (!llc->remote_busy_flag) {
608                 llc->remote_busy_flag = 1;
609                 mod_timer(&llc->busy_state_timer.timer,
610                          jiffies + llc->busy_state_timer.expire);
611         }
612         return 0;
613 }
614
615 int llc_conn_ac_opt_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
616 {
617         int rc = -ENOBUFS;
618         struct llc_sock *llc = llc_sk(sk);
619         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
620
621         if (nskb) {
622                 struct llc_sap *sap = llc->sap;
623
624                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
625                                     llc->daddr.lsap, LLC_PDU_RSP);
626                 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
627                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
628                 if (unlikely(rc))
629                         goto free;
630                 llc_conn_send_pdu(sk, nskb);
631         }
632 out:
633         return rc;
634 free:
635         kfree_skb(nskb);
636         goto out;
637 }
638
639 int llc_conn_ac_send_rr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
640 {
641         int rc = -ENOBUFS;
642         struct llc_sock *llc = llc_sk(sk);
643         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
644
645         if (nskb) {
646                 struct llc_sap *sap = llc->sap;
647
648                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
649                                     llc->daddr.lsap, LLC_PDU_CMD);
650                 llc_pdu_init_as_rr_cmd(nskb, 1, llc->vR);
651                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
652                 if (unlikely(rc))
653                         goto free;
654                 llc_conn_send_pdu(sk, nskb);
655         }
656 out:
657         return rc;
658 free:
659         kfree_skb(nskb);
660         goto out;
661 }
662
663 int llc_conn_ac_send_rr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
664 {
665         int rc = -ENOBUFS;
666         struct llc_sock *llc = llc_sk(sk);
667         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
668
669         if (nskb) {
670                 struct llc_sap *sap = llc->sap;
671                 u8 f_bit = 1;
672
673                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
674                                     llc->daddr.lsap, LLC_PDU_RSP);
675                 llc_pdu_init_as_rr_rsp(nskb, f_bit, llc->vR);
676                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
677                 if (unlikely(rc))
678                         goto free;
679                 llc_conn_send_pdu(sk, nskb);
680         }
681 out:
682         return rc;
683 free:
684         kfree_skb(nskb);
685         goto out;
686 }
687
688 int llc_conn_ac_send_ack_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
689 {
690         int rc = -ENOBUFS;
691         struct llc_sock *llc = llc_sk(sk);
692         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
693
694         if (nskb) {
695                 struct llc_sap *sap = llc->sap;
696
697                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
698                                     llc->daddr.lsap, LLC_PDU_RSP);
699                 llc_pdu_init_as_rr_rsp(nskb, 1, llc->vR);
700                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
701                 if (unlikely(rc))
702                         goto free;
703                 llc_conn_send_pdu(sk, nskb);
704         }
705 out:
706         return rc;
707 free:
708         kfree_skb(nskb);
709         goto out;
710 }
711
712 int llc_conn_ac_send_rr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
713 {
714         int rc = -ENOBUFS;
715         struct llc_sock *llc = llc_sk(sk);
716         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
717
718         if (nskb) {
719                 struct llc_sap *sap = llc->sap;
720
721                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
722                                     llc->daddr.lsap, LLC_PDU_RSP);
723                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
724                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
725                 if (unlikely(rc))
726                         goto free;
727                 llc_conn_send_pdu(sk, nskb);
728         }
729 out:
730         return rc;
731 free:
732         kfree_skb(nskb);
733         goto out;
734 }
735
736 int llc_conn_ac_send_ack_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
737 {
738         int rc = -ENOBUFS;
739         struct llc_sock *llc = llc_sk(sk);
740         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
741
742         if (nskb) {
743                 struct llc_sap *sap = llc->sap;
744
745                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
746                                     llc->daddr.lsap, LLC_PDU_RSP);
747                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
748                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
749                 if (unlikely(rc))
750                         goto free;
751                 llc_conn_send_pdu(sk, nskb);
752         }
753 out:
754         return rc;
755 free:
756         kfree_skb(nskb);
757         goto out;
758 }
759
760 void llc_conn_set_p_flag(struct sock *sk, u8 value)
761 {
762         int state_changed = llc_sk(sk)->p_flag && !value;
763
764         llc_sk(sk)->p_flag = value;
765
766         if (state_changed)
767                 sk->sk_state_change(sk);
768 }
769
770 int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
771 {
772         int rc = -ENOBUFS;
773         struct llc_sock *llc = llc_sk(sk);
774         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
775
776         if (nskb) {
777                 struct llc_sap *sap = llc->sap;
778                 u8 *dmac = llc->daddr.mac;
779
780                 if (llc->dev->flags & IFF_LOOPBACK)
781                         dmac = llc->dev->dev_addr;
782                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
783                                     llc->daddr.lsap, LLC_PDU_CMD);
784                 llc_pdu_init_as_sabme_cmd(nskb, 1);
785                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, dmac);
786                 if (unlikely(rc))
787                         goto free;
788                 llc_conn_send_pdu(sk, nskb);
789                 llc_conn_set_p_flag(sk, 1);
790         }
791 out:
792         return rc;
793 free:
794         kfree_skb(nskb);
795         goto out;
796 }
797
798 int llc_conn_ac_send_ua_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
799 {
800         u8 f_bit;
801         int rc = -ENOBUFS;
802         struct llc_sock *llc = llc_sk(sk);
803         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
804
805         llc_pdu_decode_pf_bit(skb, &f_bit);
806         if (nskb) {
807                 struct llc_sap *sap = llc->sap;
808
809                 nskb->dev = llc->dev;
810                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
811                                     llc->daddr.lsap, LLC_PDU_RSP);
812                 llc_pdu_init_as_ua_rsp(nskb, f_bit);
813                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
814                 if (unlikely(rc))
815                         goto free;
816                 llc_conn_send_pdu(sk, nskb);
817         }
818 out:
819         return rc;
820 free:
821         kfree_skb(nskb);
822         goto out;
823 }
824
825 int llc_conn_ac_set_s_flag_0(struct sock *sk, struct sk_buff *skb)
826 {
827         llc_sk(sk)->s_flag = 0;
828         return 0;
829 }
830
831 int llc_conn_ac_set_s_flag_1(struct sock *sk, struct sk_buff *skb)
832 {
833         llc_sk(sk)->s_flag = 1;
834         return 0;
835 }
836
837 int llc_conn_ac_start_p_timer(struct sock *sk, struct sk_buff *skb)
838 {
839         struct llc_sock *llc = llc_sk(sk);
840
841         llc_conn_set_p_flag(sk, 1);
842         mod_timer(&llc->pf_cycle_timer.timer,
843                   jiffies + llc->pf_cycle_timer.expire);
844         return 0;
845 }
846
847 /**
848  *      llc_conn_ac_send_ack_if_needed - check if ack is needed
849  *      @sk: current connection structure
850  *      @skb: current event
851  *
852  *      Checks number of received PDUs which have not been acknowledged, yet,
853  *      If number of them reaches to "npta"(Number of PDUs To Acknowledge) then
854  *      sends an RR response as acknowledgement for them.  Returns 0 for
855  *      success, 1 otherwise.
856  */
857 int llc_conn_ac_send_ack_if_needed(struct sock *sk, struct sk_buff *skb)
858 {
859         u8 pf_bit;
860         struct llc_sock *llc = llc_sk(sk);
861
862         llc_pdu_decode_pf_bit(skb, &pf_bit);
863         llc->ack_pf |= pf_bit & 1;
864         if (!llc->ack_must_be_send) {
865                 llc->first_pdu_Ns = llc->vR;
866                 llc->ack_must_be_send = 1;
867                 llc->ack_pf = pf_bit & 1;
868         }
869         if (((llc->vR - llc->first_pdu_Ns + 129) % 128) >= llc->npta) {
870                 llc_conn_ac_send_rr_rsp_f_set_ackpf(sk, skb);
871                 llc->ack_must_be_send   = 0;
872                 llc->ack_pf             = 0;
873                 llc_conn_ac_inc_npta_value(sk, skb);
874         }
875         return 0;
876 }
877
878 /**
879  *      llc_conn_ac_rst_sendack_flag - resets ack_must_be_send flag
880  *      @sk: current connection structure
881  *      @skb: current event
882  *
883  *      This action resets ack_must_be_send flag of given connection, this flag
884  *      indicates if there is any PDU which has not been acknowledged yet.
885  *      Returns 0 for success, 1 otherwise.
886  */
887 int llc_conn_ac_rst_sendack_flag(struct sock *sk, struct sk_buff *skb)
888 {
889         llc_sk(sk)->ack_must_be_send = llc_sk(sk)->ack_pf = 0;
890         return 0;
891 }
892
893 /**
894  *      llc_conn_ac_send_i_rsp_f_set_ackpf - acknowledge received PDUs
895  *      @sk: current connection structure
896  *      @skb: current event
897  *
898  *      Sends an I response PDU with f-bit set to ack_pf flag as acknowledge to
899  *      all received PDUs which have not been acknowledged, yet. ack_pf flag is
900  *      set to one if one PDU with p-bit set to one is received.  Returns 0 for
901  *      success, 1 otherwise.
902  */
903 static int llc_conn_ac_send_i_rsp_f_set_ackpf(struct sock *sk,
904                                               struct sk_buff *skb)
905 {
906         int rc;
907         struct llc_sock *llc = llc_sk(sk);
908         struct llc_sap *sap = llc->sap;
909
910         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
911                             llc->daddr.lsap, LLC_PDU_RSP);
912         llc_pdu_init_as_i_cmd(skb, llc->ack_pf, llc->vS, llc->vR);
913         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
914         if (likely(!rc)) {
915                 llc_conn_send_pdu(sk, skb);
916                 llc_conn_ac_inc_vs_by_1(sk, skb);
917         }
918         return rc;
919 }
920
921 /**
922  *      llc_conn_ac_send_i_as_ack - sends an I-format PDU to acknowledge rx PDUs
923  *      @sk: current connection structure.
924  *      @skb: current event.
925  *
926  *      This action sends an I-format PDU as acknowledge to received PDUs which
927  *      have not been acknowledged, yet, if there is any. By using of this
928  *      action number of acknowledgements decreases, this technic is called
929  *      piggy backing. Returns 0 for success, 1 otherwise.
930  */
931 int llc_conn_ac_send_i_as_ack(struct sock *sk, struct sk_buff *skb)
932 {
933         struct llc_sock *llc = llc_sk(sk);
934
935         if (llc->ack_must_be_send) {
936                 llc_conn_ac_send_i_rsp_f_set_ackpf(sk, skb);
937                 llc->ack_must_be_send = 0 ;
938                 llc->ack_pf = 0;
939         } else
940                 llc_conn_ac_send_i_cmd_p_set_0(sk, skb);
941         return 0;
942 }
943
944 /**
945  *      llc_conn_ac_send_rr_rsp_f_set_ackpf - ack all rx PDUs not yet acked
946  *      @sk: current connection structure.
947  *      @skb: current event.
948  *
949  *      This action sends an RR response with f-bit set to ack_pf flag as
950  *      acknowledge to all received PDUs which have not been acknowledged, yet,
951  *      if there is any. ack_pf flag indicates if a PDU has been received with
952  *      p-bit set to one. Returns 0 for success, 1 otherwise.
953  */
954 static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
955                                                struct sk_buff *skb)
956 {
957         int rc = -ENOBUFS;
958         struct llc_sock *llc = llc_sk(sk);
959         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
960
961         if (nskb) {
962                 struct llc_sap *sap = llc->sap;
963
964                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
965                                     llc->daddr.lsap, LLC_PDU_RSP);
966                 llc_pdu_init_as_rr_rsp(nskb, llc->ack_pf, llc->vR);
967                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
968                 if (unlikely(rc))
969                         goto free;
970                 llc_conn_send_pdu(sk, nskb);
971         }
972 out:
973         return rc;
974 free:
975         kfree_skb(nskb);
976         goto out;
977 }
978
979 /**
980  *      llc_conn_ac_inc_npta_value - tries to make value of npta greater
981  *      @sk: current connection structure.
982  *      @skb: current event.
983  *
984  *      After "inc_cntr" times calling of this action, "npta" increase by one.
985  *      this action tries to make vale of "npta" greater as possible; number of
986  *      acknowledgements decreases by increasing of "npta". Returns 0 for
987  *      success, 1 otherwise.
988  */
989 static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb)
990 {
991         struct llc_sock *llc = llc_sk(sk);
992
993         if (!llc->inc_cntr) {
994                 llc->dec_step = 0;
995                 llc->dec_cntr = llc->inc_cntr = 2;
996                 ++llc->npta;
997                 if (llc->npta > 127)
998                         llc->npta = 127 ;
999         } else
1000                 --llc->inc_cntr;
1001         return 0;
1002 }
1003
1004 /**
1005  *      llc_conn_ac_adjust_npta_by_rr - decreases "npta" by one
1006  *      @sk: current connection structure.
1007  *      @skb: current event.
1008  *
1009  *      After receiving "dec_cntr" times RR command, this action decreases
1010  *      "npta" by one. Returns 0 for success, 1 otherwise.
1011  */
1012 int llc_conn_ac_adjust_npta_by_rr(struct sock *sk, struct sk_buff *skb)
1013 {
1014         struct llc_sock *llc = llc_sk(sk);
1015
1016         if (!llc->connect_step && !llc->remote_busy_flag) {
1017                 if (!llc->dec_step) {
1018                         if (!llc->dec_cntr) {
1019                                 llc->inc_cntr = llc->dec_cntr = 2;
1020                                 if (llc->npta > 0)
1021                                         llc->npta = llc->npta - 1;
1022                         } else
1023                                 llc->dec_cntr -=1;
1024                 }
1025         } else
1026                 llc->connect_step = 0 ;
1027         return 0;
1028 }
1029
1030 /**
1031  *      llc_conn_ac_adjust_npta_by_rnr - decreases "npta" by one
1032  *      @sk: current connection structure.
1033  *      @skb: current event.
1034  *
1035  *      After receiving "dec_cntr" times RNR command, this action decreases
1036  *      "npta" by one. Returns 0 for success, 1 otherwise.
1037  */
1038 int llc_conn_ac_adjust_npta_by_rnr(struct sock *sk, struct sk_buff *skb)
1039 {
1040         struct llc_sock *llc = llc_sk(sk);
1041
1042         if (llc->remote_busy_flag)
1043                 if (!llc->dec_step) {
1044                         if (!llc->dec_cntr) {
1045                                 llc->inc_cntr = llc->dec_cntr = 2;
1046                                 if (llc->npta > 0)
1047                                         --llc->npta;
1048                         } else
1049                                 --llc->dec_cntr;
1050                 }
1051         return 0;
1052 }
1053
1054 /**
1055  *      llc_conn_ac_dec_tx_win_size - decreases tx window size
1056  *      @sk: current connection structure.
1057  *      @skb: current event.
1058  *
1059  *      After receiving of a REJ command or response, transmit window size is
1060  *      decreased by number of PDUs which are outstanding yet. Returns 0 for
1061  *      success, 1 otherwise.
1062  */
1063 int llc_conn_ac_dec_tx_win_size(struct sock *sk, struct sk_buff *skb)
1064 {
1065         struct llc_sock *llc = llc_sk(sk);
1066         u8 unacked_pdu = skb_queue_len(&llc->pdu_unack_q);
1067
1068         llc->k -= unacked_pdu;
1069         if (llc->k < 2)
1070                 llc->k = 2;
1071         return 0;
1072 }
1073
1074 /**
1075  *      llc_conn_ac_inc_tx_win_size - tx window size is inc by 1
1076  *      @sk: current connection structure.
1077  *      @skb: current event.
1078  *
1079  *      After receiving an RR response with f-bit set to one, transmit window
1080  *      size is increased by one. Returns 0 for success, 1 otherwise.
1081  */
1082 int llc_conn_ac_inc_tx_win_size(struct sock *sk, struct sk_buff *skb)
1083 {
1084         struct llc_sock *llc = llc_sk(sk);
1085
1086         llc->k += 1;
1087         if (llc->k > 128)
1088                 llc->k = 128 ;
1089         return 0;
1090 }
1091
1092 int llc_conn_ac_stop_all_timers(struct sock *sk, struct sk_buff *skb)
1093 {
1094         struct llc_sock *llc = llc_sk(sk);
1095
1096         del_timer(&llc->pf_cycle_timer.timer);
1097         del_timer(&llc->ack_timer.timer);
1098         del_timer(&llc->rej_sent_timer.timer);
1099         del_timer(&llc->busy_state_timer.timer);
1100         llc->ack_must_be_send = 0;
1101         llc->ack_pf = 0;
1102         return 0;
1103 }
1104
1105 int llc_conn_ac_stop_other_timers(struct sock *sk, struct sk_buff *skb)
1106 {
1107         struct llc_sock *llc = llc_sk(sk);
1108
1109         del_timer(&llc->rej_sent_timer.timer);
1110         del_timer(&llc->pf_cycle_timer.timer);
1111         del_timer(&llc->busy_state_timer.timer);
1112         llc->ack_must_be_send = 0;
1113         llc->ack_pf = 0;
1114         return 0;
1115 }
1116
1117 int llc_conn_ac_start_ack_timer(struct sock *sk, struct sk_buff *skb)
1118 {
1119         struct llc_sock *llc = llc_sk(sk);
1120
1121         mod_timer(&llc->ack_timer.timer, jiffies + llc->ack_timer.expire);
1122         return 0;
1123 }
1124
1125 int llc_conn_ac_start_rej_timer(struct sock *sk, struct sk_buff *skb)
1126 {
1127         struct llc_sock *llc = llc_sk(sk);
1128
1129         mod_timer(&llc->rej_sent_timer.timer,
1130                   jiffies + llc->rej_sent_timer.expire);
1131         return 0;
1132 }
1133
1134 int llc_conn_ac_start_ack_tmr_if_not_running(struct sock *sk,
1135                                              struct sk_buff *skb)
1136 {
1137         struct llc_sock *llc = llc_sk(sk);
1138
1139         if (!timer_pending(&llc->ack_timer.timer))
1140                 mod_timer(&llc->ack_timer.timer,
1141                           jiffies + llc->ack_timer.expire);
1142         return 0;
1143 }
1144
1145 int llc_conn_ac_stop_ack_timer(struct sock *sk, struct sk_buff *skb)
1146 {
1147         del_timer(&llc_sk(sk)->ack_timer.timer);
1148         return 0;
1149 }
1150
1151 int llc_conn_ac_stop_p_timer(struct sock *sk, struct sk_buff *skb)
1152 {
1153         struct llc_sock *llc = llc_sk(sk);
1154
1155         del_timer(&llc->pf_cycle_timer.timer);
1156         llc_conn_set_p_flag(sk, 0);
1157         return 0;
1158 }
1159
1160 int llc_conn_ac_stop_rej_timer(struct sock *sk, struct sk_buff *skb)
1161 {
1162         del_timer(&llc_sk(sk)->rej_sent_timer.timer);
1163         return 0;
1164 }
1165
1166 int llc_conn_ac_upd_nr_received(struct sock *sk, struct sk_buff *skb)
1167 {
1168         int acked;
1169         u16 unacked = 0;
1170         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1171         struct llc_sock *llc = llc_sk(sk);
1172
1173         llc->last_nr = PDU_SUPV_GET_Nr(pdu);
1174         acked = llc_conn_remove_acked_pdus(sk, llc->last_nr, &unacked);
1175         /* On loopback we don't queue I frames in unack_pdu_q queue. */
1176         if (acked > 0 || (llc->dev->flags & IFF_LOOPBACK)) {
1177                 llc->retry_count = 0;
1178                 del_timer(&llc->ack_timer.timer);
1179                 if (llc->failed_data_req) {
1180                         /* already, we did not accept data from upper layer
1181                          * (tx_window full or unacceptable state). Now, we
1182                          * can send data and must inform to upper layer.
1183                          */
1184                         llc->failed_data_req = 0;
1185                         llc_conn_ac_data_confirm(sk, skb);
1186                 }
1187                 if (unacked)
1188                         mod_timer(&llc->ack_timer.timer,
1189                                   jiffies + llc->ack_timer.expire);
1190         } else if (llc->failed_data_req) {
1191                 u8 f_bit;
1192
1193                 llc_pdu_decode_pf_bit(skb, &f_bit);
1194                 if (f_bit == 1) {
1195                         llc->failed_data_req = 0;
1196                         llc_conn_ac_data_confirm(sk, skb);
1197                 }
1198         }
1199         return 0;
1200 }
1201
1202 int llc_conn_ac_upd_p_flag(struct sock *sk, struct sk_buff *skb)
1203 {
1204         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1205
1206         if (LLC_PDU_IS_RSP(pdu)) {
1207                 u8 f_bit;
1208
1209                 llc_pdu_decode_pf_bit(skb, &f_bit);
1210                 if (f_bit) {
1211                         llc_conn_set_p_flag(sk, 0);
1212                         llc_conn_ac_stop_p_timer(sk, skb);
1213                 }
1214         }
1215         return 0;
1216 }
1217
1218 int llc_conn_ac_set_data_flag_2(struct sock *sk, struct sk_buff *skb)
1219 {
1220         llc_sk(sk)->data_flag = 2;
1221         return 0;
1222 }
1223
1224 int llc_conn_ac_set_data_flag_0(struct sock *sk, struct sk_buff *skb)
1225 {
1226         llc_sk(sk)->data_flag = 0;
1227         return 0;
1228 }
1229
1230 int llc_conn_ac_set_data_flag_1(struct sock *sk, struct sk_buff *skb)
1231 {
1232         llc_sk(sk)->data_flag = 1;
1233         return 0;
1234 }
1235
1236 int llc_conn_ac_set_data_flag_1_if_data_flag_eq_0(struct sock *sk,
1237                                                   struct sk_buff *skb)
1238 {
1239         if (!llc_sk(sk)->data_flag)
1240                 llc_sk(sk)->data_flag = 1;
1241         return 0;
1242 }
1243
1244 int llc_conn_ac_set_p_flag_0(struct sock *sk, struct sk_buff *skb)
1245 {
1246         llc_conn_set_p_flag(sk, 0);
1247         return 0;
1248 }
1249
1250 static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb)
1251 {
1252         llc_conn_set_p_flag(sk, 1);
1253         return 0;
1254 }
1255
1256 int llc_conn_ac_set_remote_busy_0(struct sock *sk, struct sk_buff *skb)
1257 {
1258         llc_sk(sk)->remote_busy_flag = 0;
1259         return 0;
1260 }
1261
1262 int llc_conn_ac_set_cause_flag_0(struct sock *sk, struct sk_buff *skb)
1263 {
1264         llc_sk(sk)->cause_flag = 0;
1265         return 0;
1266 }
1267
1268 int llc_conn_ac_set_cause_flag_1(struct sock *sk, struct sk_buff *skb)
1269 {
1270         llc_sk(sk)->cause_flag = 1;
1271         return 0;
1272 }
1273
1274 int llc_conn_ac_set_retry_cnt_0(struct sock *sk, struct sk_buff *skb)
1275 {
1276         llc_sk(sk)->retry_count = 0;
1277         return 0;
1278 }
1279
1280 int llc_conn_ac_inc_retry_cnt_by_1(struct sock *sk, struct sk_buff *skb)
1281 {
1282         llc_sk(sk)->retry_count++;
1283         return 0;
1284 }
1285
1286 int llc_conn_ac_set_vr_0(struct sock *sk, struct sk_buff *skb)
1287 {
1288         llc_sk(sk)->vR = 0;
1289         return 0;
1290 }
1291
1292 int llc_conn_ac_inc_vr_by_1(struct sock *sk, struct sk_buff *skb)
1293 {
1294         llc_sk(sk)->vR = PDU_GET_NEXT_Vr(llc_sk(sk)->vR);
1295         return 0;
1296 }
1297
1298 int llc_conn_ac_set_vs_0(struct sock *sk, struct sk_buff *skb)
1299 {
1300         llc_sk(sk)->vS = 0;
1301         return 0;
1302 }
1303
1304 int llc_conn_ac_set_vs_nr(struct sock *sk, struct sk_buff *skb)
1305 {
1306         llc_sk(sk)->vS = llc_sk(sk)->last_nr;
1307         return 0;
1308 }
1309
1310 static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb)
1311 {
1312         llc_sk(sk)->vS = (llc_sk(sk)->vS + 1) % 128;
1313         return 0;
1314 }
1315
1316 static void llc_conn_tmr_common_cb(unsigned long timeout_data, u8 type)
1317 {
1318         struct sock *sk = (struct sock *)timeout_data;
1319         struct sk_buff *skb = alloc_skb(0, GFP_ATOMIC);
1320
1321         bh_lock_sock(sk);
1322         if (skb) {
1323                 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
1324
1325                 skb_set_owner_r(skb, sk);
1326                 ev->type = type;
1327                 llc_process_tmr_ev(sk, skb);
1328         }
1329         bh_unlock_sock(sk);
1330 }
1331
1332 void llc_conn_pf_cycle_tmr_cb(unsigned long timeout_data)
1333 {
1334         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_P_TMR);
1335 }
1336
1337 void llc_conn_busy_tmr_cb(unsigned long timeout_data)
1338 {
1339         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_BUSY_TMR);
1340 }
1341
1342 void llc_conn_ack_tmr_cb(unsigned long timeout_data)
1343 {
1344         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_ACK_TMR);
1345 }
1346
1347 void llc_conn_rej_tmr_cb(unsigned long timeout_data)
1348 {
1349         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_REJ_TMR);
1350 }
1351
1352 int llc_conn_ac_rst_vs(struct sock *sk, struct sk_buff *skb)
1353 {
1354         llc_sk(sk)->X = llc_sk(sk)->vS;
1355         llc_conn_ac_set_vs_nr(sk, skb);
1356         return 0;
1357 }
1358
1359 int llc_conn_ac_upd_vs(struct sock *sk, struct sk_buff *skb)
1360 {
1361         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1362         u8 nr = PDU_SUPV_GET_Nr(pdu);
1363
1364         if (llc_circular_between(llc_sk(sk)->vS, nr, llc_sk(sk)->X))
1365                 llc_conn_ac_set_vs_nr(sk, skb);
1366         return 0;
1367 }
1368
1369 /*
1370  * Non-standard actions; these not contained in IEEE specification; for
1371  * our own usage
1372  */
1373 /**
1374  *      llc_conn_disc - removes connection from SAP list and frees it
1375  *      @sk: closed connection
1376  *      @skb: occurred event
1377  */
1378 int llc_conn_disc(struct sock *sk, struct sk_buff *skb)
1379 {
1380         /* FIXME: this thing seems to want to die */
1381         return 0;
1382 }
1383
1384 /**
1385  *      llc_conn_reset - resets connection
1386  *      @sk : reseting connection.
1387  *      @skb: occurred event.
1388  *
1389  *      Stop all timers, empty all queues and reset all flags.
1390  */
1391 int llc_conn_reset(struct sock *sk, struct sk_buff *skb)
1392 {
1393         llc_sk_reset(sk);
1394         return 0;
1395 }
1396
1397 /**
1398  *      llc_circular_between - designates that b is between a and c or not
1399  *      @a: lower bound
1400  *      @b: element to see if is between a and b
1401  *      @c: upper bound
1402  *
1403  *      This function designates that b is between a and c or not (for example,
1404  *      0 is between 127 and 1). Returns 1 if b is between a and c, 0
1405  *      otherwise.
1406  */
1407 u8 llc_circular_between(u8 a, u8 b, u8 c)
1408 {
1409         b = b - a;
1410         c = c - a;
1411         return b <= c;
1412 }
1413
1414 /**
1415  *      llc_process_tmr_ev - timer backend
1416  *      @sk: active connection
1417  *      @skb: occurred event
1418  *
1419  *      This function is called from timer callback functions. When connection
1420  *      is busy (during sending a data frame) timer expiration event must be
1421  *      queued. Otherwise this event can be sent to connection state machine.
1422  *      Queued events will process by llc_backlog_rcv function after sending
1423  *      data frame.
1424  */
1425 static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb)
1426 {
1427         if (llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC) {
1428                 printk(KERN_WARNING "%s: timer called on closed connection\n",
1429                        __FUNCTION__);
1430                 kfree_skb(skb);
1431         } else {
1432                 if (!sock_owned_by_user(sk))
1433                         llc_conn_state_process(sk, skb);
1434                 else {
1435                         llc_set_backlog_type(skb, LLC_EVENT);
1436                         sk_add_backlog(sk, skb);
1437                 }
1438         }
1439 }