[XFRM] netlink: Use nlmsg_parse() to parse attributes
[linux-2.6] / 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
31 static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb);
32 static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb);
33 static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *ev);
34
35 static int llc_conn_ac_inc_npta_value(struct sock *sk, struct sk_buff *skb);
36
37 static int llc_conn_ac_send_rr_rsp_f_set_ackpf(struct sock *sk,
38                                                struct sk_buff *skb);
39
40 static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb);
41
42 #define INCORRECT 0
43
44 int llc_conn_ac_clear_remote_busy(struct sock *sk, struct sk_buff *skb)
45 {
46         struct llc_sock *llc = llc_sk(sk);
47
48         if (llc->remote_busy_flag) {
49                 u8 nr;
50                 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
51
52                 llc->remote_busy_flag = 0;
53                 del_timer(&llc->busy_state_timer.timer);
54                 nr = LLC_I_GET_NR(pdu);
55                 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
56         }
57         return 0;
58 }
59
60 int llc_conn_ac_conn_ind(struct sock *sk, struct sk_buff *skb)
61 {
62         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
63
64         ev->ind_prim = LLC_CONN_PRIM;
65         return 0;
66 }
67
68 int llc_conn_ac_conn_confirm(struct sock *sk, struct sk_buff *skb)
69 {
70         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
71
72         ev->cfm_prim = LLC_CONN_PRIM;
73         return 0;
74 }
75
76 static int llc_conn_ac_data_confirm(struct sock *sk, struct sk_buff *skb)
77 {
78         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
79
80         ev->cfm_prim = LLC_DATA_PRIM;
81         return 0;
82 }
83
84 int llc_conn_ac_data_ind(struct sock *sk, struct sk_buff *skb)
85 {
86         llc_conn_rtn_pdu(sk, skb);
87         return 0;
88 }
89
90 int llc_conn_ac_disc_ind(struct sock *sk, struct sk_buff *skb)
91 {
92         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
93         u8 reason = 0;
94         int rc = 0;
95
96         if (ev->type == LLC_CONN_EV_TYPE_PDU) {
97                 struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
98
99                 if (LLC_PDU_IS_RSP(pdu) &&
100                     LLC_PDU_TYPE_IS_U(pdu) &&
101                     LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_DM)
102                         reason = LLC_DISC_REASON_RX_DM_RSP_PDU;
103                 else if (LLC_PDU_IS_CMD(pdu) &&
104                            LLC_PDU_TYPE_IS_U(pdu) &&
105                            LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_DISC)
106                         reason = LLC_DISC_REASON_RX_DISC_CMD_PDU;
107         } else if (ev->type == LLC_CONN_EV_TYPE_ACK_TMR)
108                 reason = LLC_DISC_REASON_ACK_TMR_EXP;
109         else
110                 rc = -EINVAL;
111         if (!rc) {
112                 ev->reason   = reason;
113                 ev->ind_prim = LLC_DISC_PRIM;
114         }
115         return rc;
116 }
117
118 int llc_conn_ac_disc_confirm(struct sock *sk, struct sk_buff *skb)
119 {
120         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
121
122         ev->reason   = ev->status;
123         ev->cfm_prim = LLC_DISC_PRIM;
124         return 0;
125 }
126
127 int llc_conn_ac_rst_ind(struct sock *sk, struct sk_buff *skb)
128 {
129         u8 reason = 0;
130         int rc = 1;
131         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
132         struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);
133         struct llc_sock *llc = llc_sk(sk);
134
135         switch (ev->type) {
136         case LLC_CONN_EV_TYPE_PDU:
137                 if (LLC_PDU_IS_RSP(pdu) &&
138                     LLC_PDU_TYPE_IS_U(pdu) &&
139                     LLC_U_PDU_RSP(pdu) == LLC_2_PDU_RSP_FRMR) {
140                         reason = LLC_RESET_REASON_LOCAL;
141                         rc = 0;
142                 } else if (LLC_PDU_IS_CMD(pdu) &&
143                            LLC_PDU_TYPE_IS_U(pdu) &&
144                            LLC_U_PDU_CMD(pdu) == LLC_2_PDU_CMD_SABME) {
145                         reason = LLC_RESET_REASON_REMOTE;
146                         rc = 0;
147                 }
148                 break;
149         case LLC_CONN_EV_TYPE_ACK_TMR:
150         case LLC_CONN_EV_TYPE_P_TMR:
151         case LLC_CONN_EV_TYPE_REJ_TMR:
152         case LLC_CONN_EV_TYPE_BUSY_TMR:
153                 if (llc->retry_count > llc->n2) {
154                         reason = LLC_RESET_REASON_LOCAL;
155                         rc = 0;
156                 }
157                 break;
158         }
159         if (!rc) {
160                 ev->reason   = reason;
161                 ev->ind_prim = LLC_RESET_PRIM;
162         }
163         return rc;
164 }
165
166 int llc_conn_ac_rst_confirm(struct sock *sk, struct sk_buff *skb)
167 {
168         struct llc_conn_state_ev *ev = llc_conn_ev(skb);
169
170         ev->reason   = 0;
171         ev->cfm_prim = LLC_RESET_PRIM;
172         return 0;
173 }
174
175 int llc_conn_ac_clear_remote_busy_if_f_eq_1(struct sock *sk,
176                                             struct sk_buff *skb)
177 {
178         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
179
180         if (LLC_PDU_IS_RSP(pdu) &&
181             LLC_PDU_TYPE_IS_I(pdu) &&
182             LLC_I_PF_IS_1(pdu) && llc_sk(sk)->ack_pf)
183                 llc_conn_ac_clear_remote_busy(sk, skb);
184         return 0;
185 }
186
187 int llc_conn_ac_stop_rej_tmr_if_data_flag_eq_2(struct sock *sk,
188                                                struct sk_buff *skb)
189 {
190         struct llc_sock *llc = llc_sk(sk);
191
192         if (llc->data_flag == 2)
193                 del_timer(&llc->rej_sent_timer.timer);
194         return 0;
195 }
196
197 int llc_conn_ac_send_disc_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
198 {
199         int rc = -ENOBUFS;
200         struct llc_sock *llc = llc_sk(sk);
201         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
202
203         if (nskb) {
204                 struct llc_sap *sap = llc->sap;
205
206                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
207                                     llc->daddr.lsap, LLC_PDU_CMD);
208                 llc_pdu_init_as_disc_cmd(nskb, 1);
209                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
210                 if (unlikely(rc))
211                         goto free;
212                 llc_conn_send_pdu(sk, nskb);
213                 llc_conn_ac_set_p_flag_1(sk, skb);
214         }
215 out:
216         return rc;
217 free:
218         kfree_skb(nskb);
219         goto out;
220 }
221
222 int llc_conn_ac_send_dm_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
223 {
224         int rc = -ENOBUFS;
225         struct llc_sock *llc = llc_sk(sk);
226         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
227
228         if (nskb) {
229                 struct llc_sap *sap = llc->sap;
230                 u8 f_bit;
231
232                 llc_pdu_decode_pf_bit(skb, &f_bit);
233                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
234                                     llc->daddr.lsap, LLC_PDU_RSP);
235                 llc_pdu_init_as_dm_rsp(nskb, f_bit);
236                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
237                 if (unlikely(rc))
238                         goto free;
239                 llc_conn_send_pdu(sk, nskb);
240         }
241 out:
242         return rc;
243 free:
244         kfree_skb(nskb);
245         goto out;
246 }
247
248 int llc_conn_ac_send_dm_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
249 {
250         int rc = -ENOBUFS;
251         struct llc_sock *llc = llc_sk(sk);
252         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
253
254         if (nskb) {
255                 struct llc_sap *sap = llc->sap;
256
257                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
258                                     llc->daddr.lsap, LLC_PDU_RSP);
259                 llc_pdu_init_as_dm_rsp(nskb, 1);
260                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
261                 if (unlikely(rc))
262                         goto free;
263                 llc_conn_send_pdu(sk, nskb);
264         }
265 out:
266         return rc;
267 free:
268         kfree_skb(nskb);
269         goto out;
270 }
271
272 int llc_conn_ac_send_frmr_rsp_f_set_x(struct sock *sk, struct sk_buff *skb)
273 {
274         u8 f_bit;
275         int rc = -ENOBUFS;
276         struct sk_buff *nskb;
277         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
278         struct llc_sock *llc = llc_sk(sk);
279
280         llc->rx_pdu_hdr = *((u32 *)pdu);
281         if (LLC_PDU_IS_CMD(pdu))
282                 llc_pdu_decode_pf_bit(skb, &f_bit);
283         else
284                 f_bit = 0;
285         nskb = llc_alloc_frame(sk, llc->dev);
286         if (nskb) {
287                 struct llc_sap *sap = llc->sap;
288
289                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
290                                     llc->daddr.lsap, LLC_PDU_RSP);
291                 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
292                                          llc->vR, INCORRECT);
293                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
294                 if (unlikely(rc))
295                         goto free;
296                 llc_conn_send_pdu(sk, nskb);
297         }
298 out:
299         return rc;
300 free:
301         kfree_skb(nskb);
302         goto out;
303 }
304
305 int llc_conn_ac_resend_frmr_rsp_f_set_0(struct sock *sk, struct sk_buff *skb)
306 {
307         int rc = -ENOBUFS;
308         struct llc_sock *llc = llc_sk(sk);
309         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
310
311         if (nskb) {
312                 struct llc_sap *sap = llc->sap;
313                 struct llc_pdu_sn *pdu = (struct llc_pdu_sn *)&llc->rx_pdu_hdr;
314
315                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
316                                     llc->daddr.lsap, LLC_PDU_RSP);
317                 llc_pdu_init_as_frmr_rsp(nskb, pdu, 0, llc->vS,
318                                          llc->vR, INCORRECT);
319                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
320                 if (unlikely(rc))
321                         goto free;
322                 llc_conn_send_pdu(sk, nskb);
323         }
324 out:
325         return rc;
326 free:
327         kfree_skb(nskb);
328         goto out;
329 }
330
331 int llc_conn_ac_resend_frmr_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
332 {
333         u8 f_bit;
334         int rc = -ENOBUFS;
335         struct sk_buff *nskb;
336         struct llc_sock *llc = llc_sk(sk);
337
338         llc_pdu_decode_pf_bit(skb, &f_bit);
339         nskb = llc_alloc_frame(sk, llc->dev);
340         if (nskb) {
341                 struct llc_sap *sap = llc->sap;
342                 struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
343
344                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
345                                     llc->daddr.lsap, LLC_PDU_RSP);
346                 llc_pdu_init_as_frmr_rsp(nskb, pdu, f_bit, llc->vS,
347                                          llc->vR, INCORRECT);
348                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
349                 if (unlikely(rc))
350                         goto free;
351                 llc_conn_send_pdu(sk, nskb);
352         }
353 out:
354         return rc;
355 free:
356         kfree_skb(nskb);
357         goto out;
358 }
359
360 int llc_conn_ac_send_i_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
361 {
362         int rc;
363         struct llc_sock *llc = llc_sk(sk);
364         struct llc_sap *sap = llc->sap;
365
366         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
367                             llc->daddr.lsap, LLC_PDU_CMD);
368         llc_pdu_init_as_i_cmd(skb, 1, llc->vS, llc->vR);
369         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
370         if (likely(!rc)) {
371                 llc_conn_send_pdu(sk, skb);
372                 llc_conn_ac_inc_vs_by_1(sk, skb);
373         }
374         return rc;
375 }
376
377 static int llc_conn_ac_send_i_cmd_p_set_0(struct sock *sk, struct sk_buff *skb)
378 {
379         int rc;
380         struct llc_sock *llc = llc_sk(sk);
381         struct llc_sap *sap = llc->sap;
382
383         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
384                             llc->daddr.lsap, LLC_PDU_CMD);
385         llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
386         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
387         if (likely(!rc)) {
388                 llc_conn_send_pdu(sk, skb);
389                 llc_conn_ac_inc_vs_by_1(sk, skb);
390         }
391         return rc;
392 }
393
394 int llc_conn_ac_send_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
395 {
396         int rc;
397         struct llc_sock *llc = llc_sk(sk);
398         struct llc_sap *sap = llc->sap;
399
400         llc_pdu_header_init(skb, LLC_PDU_TYPE_I, sap->laddr.lsap,
401                             llc->daddr.lsap, LLC_PDU_CMD);
402         llc_pdu_init_as_i_cmd(skb, 0, llc->vS, llc->vR);
403         rc = llc_mac_hdr_init(skb, llc->dev->dev_addr, llc->daddr.mac);
404         if (likely(!rc)) {
405                 llc_conn_send_pdu(sk, skb);
406                 llc_conn_ac_inc_vs_by_1(sk, skb);
407         }
408         return 0;
409 }
410
411 int llc_conn_ac_resend_i_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
412 {
413         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
414         u8 nr = LLC_I_GET_NR(pdu);
415
416         llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
417         return 0;
418 }
419
420 int llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(struct sock *sk,
421                                                 struct sk_buff *skb)
422 {
423         u8 nr;
424         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
425         int rc = -ENOBUFS;
426         struct llc_sock *llc = llc_sk(sk);
427         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
428
429         if (nskb) {
430                 struct llc_sap *sap = llc->sap;
431
432                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
433                                     llc->daddr.lsap, LLC_PDU_RSP);
434                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
435                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
436                 if (likely(!rc))
437                         llc_conn_send_pdu(sk, nskb);
438                 else
439                         kfree_skb(skb);
440         }
441         if (rc) {
442                 nr = LLC_I_GET_NR(pdu);
443                 rc = 0;
444                 llc_conn_resend_i_pdu_as_cmd(sk, nr, 0);
445         }
446         return rc;
447 }
448
449 int llc_conn_ac_resend_i_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
450 {
451         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
452         u8 nr = LLC_I_GET_NR(pdu);
453
454         llc_conn_resend_i_pdu_as_rsp(sk, nr, 1);
455         return 0;
456 }
457
458 int llc_conn_ac_send_rej_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
459 {
460         int rc = -ENOBUFS;
461         struct llc_sock *llc = llc_sk(sk);
462         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
463
464         if (nskb) {
465                 struct llc_sap *sap = llc->sap;
466
467                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
468                                     llc->daddr.lsap, LLC_PDU_CMD);
469                 llc_pdu_init_as_rej_cmd(nskb, 1, llc->vR);
470                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
471                 if (unlikely(rc))
472                         goto free;
473                 llc_conn_send_pdu(sk, nskb);
474         }
475 out:
476         return rc;
477 free:
478         kfree_skb(nskb);
479         goto out;
480 }
481
482 int llc_conn_ac_send_rej_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
483 {
484         int rc = -ENOBUFS;
485         struct llc_sock *llc = llc_sk(sk);
486         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
487
488         if (nskb) {
489                 struct llc_sap *sap = llc->sap;
490
491                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
492                                     llc->daddr.lsap, LLC_PDU_RSP);
493                 llc_pdu_init_as_rej_rsp(nskb, 1, llc->vR);
494                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
495                 if (unlikely(rc))
496                         goto free;
497                 llc_conn_send_pdu(sk, nskb);
498         }
499 out:
500         return rc;
501 free:
502         kfree_skb(nskb);
503         goto out;
504 }
505
506 int llc_conn_ac_send_rej_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
507 {
508         int rc = -ENOBUFS;
509         struct llc_sock *llc = llc_sk(sk);
510         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
511
512         if (nskb) {
513                 struct llc_sap *sap = llc->sap;
514
515                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
516                                     llc->daddr.lsap, LLC_PDU_RSP);
517                 llc_pdu_init_as_rej_rsp(nskb, 0, llc->vR);
518                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
519                 if (unlikely(rc))
520                         goto free;
521                 llc_conn_send_pdu(sk, nskb);
522         }
523 out:
524         return rc;
525 free:
526         kfree_skb(nskb);
527         goto out;
528 }
529
530 int llc_conn_ac_send_rnr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
531 {
532         int rc = -ENOBUFS;
533         struct llc_sock *llc = llc_sk(sk);
534         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
535
536         if (nskb) {
537                 struct llc_sap *sap = llc->sap;
538
539                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
540                                     llc->daddr.lsap, LLC_PDU_CMD);
541                 llc_pdu_init_as_rnr_cmd(nskb, 1, llc->vR);
542                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
543                 if (unlikely(rc))
544                         goto free;
545                 llc_conn_send_pdu(sk, nskb);
546         }
547 out:
548         return rc;
549 free:
550         kfree_skb(nskb);
551         goto out;
552 }
553
554 int llc_conn_ac_send_rnr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
555 {
556         int rc = -ENOBUFS;
557         struct llc_sock *llc = llc_sk(sk);
558         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
559
560         if (nskb) {
561                 struct llc_sap *sap = llc->sap;
562
563                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
564                                     llc->daddr.lsap, LLC_PDU_RSP);
565                 llc_pdu_init_as_rnr_rsp(nskb, 1, llc->vR);
566                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
567                 if (unlikely(rc))
568                         goto free;
569                 llc_conn_send_pdu(sk, nskb);
570         }
571 out:
572         return rc;
573 free:
574         kfree_skb(nskb);
575         goto out;
576 }
577
578 int llc_conn_ac_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
579 {
580         int rc = -ENOBUFS;
581         struct llc_sock *llc = llc_sk(sk);
582         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
583
584         if (nskb) {
585                 struct llc_sap *sap = llc->sap;
586
587                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
588                                     llc->daddr.lsap, LLC_PDU_RSP);
589                 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
590                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
591                 if (unlikely(rc))
592                         goto free;
593                 llc_conn_send_pdu(sk, nskb);
594         }
595 out:
596         return rc;
597 free:
598         kfree_skb(nskb);
599         goto out;
600 }
601
602 int llc_conn_ac_set_remote_busy(struct sock *sk, struct sk_buff *skb)
603 {
604         struct llc_sock *llc = llc_sk(sk);
605
606         if (!llc->remote_busy_flag) {
607                 llc->remote_busy_flag = 1;
608                 mod_timer(&llc->busy_state_timer.timer,
609                          jiffies + llc->busy_state_timer.expire);
610         }
611         return 0;
612 }
613
614 int llc_conn_ac_opt_send_rnr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
615 {
616         int rc = -ENOBUFS;
617         struct llc_sock *llc = llc_sk(sk);
618         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
619
620         if (nskb) {
621                 struct llc_sap *sap = llc->sap;
622
623                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
624                                     llc->daddr.lsap, LLC_PDU_RSP);
625                 llc_pdu_init_as_rnr_rsp(nskb, 0, llc->vR);
626                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
627                 if (unlikely(rc))
628                         goto free;
629                 llc_conn_send_pdu(sk, nskb);
630         }
631 out:
632         return rc;
633 free:
634         kfree_skb(nskb);
635         goto out;
636 }
637
638 int llc_conn_ac_send_rr_cmd_p_set_1(struct sock *sk, struct sk_buff *skb)
639 {
640         int rc = -ENOBUFS;
641         struct llc_sock *llc = llc_sk(sk);
642         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
643
644         if (nskb) {
645                 struct llc_sap *sap = llc->sap;
646
647                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
648                                     llc->daddr.lsap, LLC_PDU_CMD);
649                 llc_pdu_init_as_rr_cmd(nskb, 1, llc->vR);
650                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
651                 if (unlikely(rc))
652                         goto free;
653                 llc_conn_send_pdu(sk, nskb);
654         }
655 out:
656         return rc;
657 free:
658         kfree_skb(nskb);
659         goto out;
660 }
661
662 int llc_conn_ac_send_rr_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
663 {
664         int rc = -ENOBUFS;
665         struct llc_sock *llc = llc_sk(sk);
666         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
667
668         if (nskb) {
669                 struct llc_sap *sap = llc->sap;
670                 u8 f_bit = 1;
671
672                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
673                                     llc->daddr.lsap, LLC_PDU_RSP);
674                 llc_pdu_init_as_rr_rsp(nskb, f_bit, llc->vR);
675                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
676                 if (unlikely(rc))
677                         goto free;
678                 llc_conn_send_pdu(sk, nskb);
679         }
680 out:
681         return rc;
682 free:
683         kfree_skb(nskb);
684         goto out;
685 }
686
687 int llc_conn_ac_send_ack_rsp_f_set_1(struct sock *sk, struct sk_buff *skb)
688 {
689         int rc = -ENOBUFS;
690         struct llc_sock *llc = llc_sk(sk);
691         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
692
693         if (nskb) {
694                 struct llc_sap *sap = llc->sap;
695
696                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
697                                     llc->daddr.lsap, LLC_PDU_RSP);
698                 llc_pdu_init_as_rr_rsp(nskb, 1, llc->vR);
699                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
700                 if (unlikely(rc))
701                         goto free;
702                 llc_conn_send_pdu(sk, nskb);
703         }
704 out:
705         return rc;
706 free:
707         kfree_skb(nskb);
708         goto out;
709 }
710
711 int llc_conn_ac_send_rr_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
712 {
713         int rc = -ENOBUFS;
714         struct llc_sock *llc = llc_sk(sk);
715         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
716
717         if (nskb) {
718                 struct llc_sap *sap = llc->sap;
719
720                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
721                                     llc->daddr.lsap, LLC_PDU_RSP);
722                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
723                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
724                 if (unlikely(rc))
725                         goto free;
726                 llc_conn_send_pdu(sk, nskb);
727         }
728 out:
729         return rc;
730 free:
731         kfree_skb(nskb);
732         goto out;
733 }
734
735 int llc_conn_ac_send_ack_xxx_x_set_0(struct sock *sk, struct sk_buff *skb)
736 {
737         int rc = -ENOBUFS;
738         struct llc_sock *llc = llc_sk(sk);
739         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
740
741         if (nskb) {
742                 struct llc_sap *sap = llc->sap;
743
744                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_S, sap->laddr.lsap,
745                                     llc->daddr.lsap, LLC_PDU_RSP);
746                 llc_pdu_init_as_rr_rsp(nskb, 0, llc->vR);
747                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
748                 if (unlikely(rc))
749                         goto free;
750                 llc_conn_send_pdu(sk, nskb);
751         }
752 out:
753         return rc;
754 free:
755         kfree_skb(nskb);
756         goto out;
757 }
758
759 void llc_conn_set_p_flag(struct sock *sk, u8 value)
760 {
761         int state_changed = llc_sk(sk)->p_flag && !value;
762
763         llc_sk(sk)->p_flag = value;
764
765         if (state_changed)
766                 sk->sk_state_change(sk);
767 }
768
769 int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
770 {
771         int rc = -ENOBUFS;
772         struct llc_sock *llc = llc_sk(sk);
773         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
774
775         if (nskb) {
776                 struct llc_sap *sap = llc->sap;
777                 u8 *dmac = llc->daddr.mac;
778
779                 if (llc->dev->flags & IFF_LOOPBACK)
780                         dmac = llc->dev->dev_addr;
781                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
782                                     llc->daddr.lsap, LLC_PDU_CMD);
783                 llc_pdu_init_as_sabme_cmd(nskb, 1);
784                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, dmac);
785                 if (unlikely(rc))
786                         goto free;
787                 llc_conn_send_pdu(sk, nskb);
788                 llc_conn_set_p_flag(sk, 1);
789         }
790 out:
791         return rc;
792 free:
793         kfree_skb(nskb);
794         goto out;
795 }
796
797 int llc_conn_ac_send_ua_rsp_f_set_p(struct sock *sk, struct sk_buff *skb)
798 {
799         u8 f_bit;
800         int rc = -ENOBUFS;
801         struct llc_sock *llc = llc_sk(sk);
802         struct sk_buff *nskb = llc_alloc_frame(sk, llc->dev);
803
804         llc_pdu_decode_pf_bit(skb, &f_bit);
805         if (nskb) {
806                 struct llc_sap *sap = llc->sap;
807
808                 nskb->dev = llc->dev;
809                 llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, sap->laddr.lsap,
810                                     llc->daddr.lsap, LLC_PDU_RSP);
811                 llc_pdu_init_as_ua_rsp(nskb, f_bit);
812                 rc = llc_mac_hdr_init(nskb, llc->dev->dev_addr, llc->daddr.mac);
813                 if (unlikely(rc))
814                         goto free;
815                 llc_conn_send_pdu(sk, nskb);
816         }
817 out:
818         return rc;
819 free:
820         kfree_skb(nskb);
821         goto out;
822 }
823
824 int llc_conn_ac_set_s_flag_0(struct sock *sk, struct sk_buff *skb)
825 {
826         llc_sk(sk)->s_flag = 0;
827         return 0;
828 }
829
830 int llc_conn_ac_set_s_flag_1(struct sock *sk, struct sk_buff *skb)
831 {
832         llc_sk(sk)->s_flag = 1;
833         return 0;
834 }
835
836 int llc_conn_ac_start_p_timer(struct sock *sk, struct sk_buff *skb)
837 {
838         struct llc_sock *llc = llc_sk(sk);
839
840         llc_conn_set_p_flag(sk, 1);
841         mod_timer(&llc->pf_cycle_timer.timer,
842                   jiffies + llc->pf_cycle_timer.expire);
843         return 0;
844 }
845
846 /**
847  *      llc_conn_ac_send_ack_if_needed - check if ack is needed
848  *      @sk: current connection structure
849  *      @skb: current event
850  *
851  *      Checks number of received PDUs which have not been acknowledged, yet,
852  *      If number of them reaches to "npta"(Number of PDUs To Acknowledge) then
853  *      sends an RR response as acknowledgement for them.  Returns 0 for
854  *      success, 1 otherwise.
855  */
856 int llc_conn_ac_send_ack_if_needed(struct sock *sk, struct sk_buff *skb)
857 {
858         u8 pf_bit;
859         struct llc_sock *llc = llc_sk(sk);
860
861         llc_pdu_decode_pf_bit(skb, &pf_bit);
862         llc->ack_pf |= pf_bit & 1;
863         if (!llc->ack_must_be_send) {
864                 llc->first_pdu_Ns = llc->vR;
865                 llc->ack_must_be_send = 1;
866                 llc->ack_pf = pf_bit & 1;
867         }
868         if (((llc->vR - llc->first_pdu_Ns + 1 + LLC_2_SEQ_NBR_MODULO)
869                         % LLC_2_SEQ_NBR_MODULO) >= 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 > (u8) ~LLC_2_SEQ_NBR_MODULO)
998                         llc->npta = (u8) ~LLC_2_SEQ_NBR_MODULO;
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         if (llc->k - unacked_pdu < 1)
1069                 llc->k = 1;
1070         else
1071                 llc->k -= unacked_pdu;
1072         return 0;
1073 }
1074
1075 /**
1076  *      llc_conn_ac_inc_tx_win_size - tx window size is inc by 1
1077  *      @sk: current connection structure.
1078  *      @skb: current event.
1079  *
1080  *      After receiving an RR response with f-bit set to one, transmit window
1081  *      size is increased by one. Returns 0 for success, 1 otherwise.
1082  */
1083 int llc_conn_ac_inc_tx_win_size(struct sock *sk, struct sk_buff *skb)
1084 {
1085         struct llc_sock *llc = llc_sk(sk);
1086
1087         llc->k += 1;
1088         if (llc->k > (u8) ~LLC_2_SEQ_NBR_MODULO)
1089                 llc->k = (u8) ~LLC_2_SEQ_NBR_MODULO;
1090         return 0;
1091 }
1092
1093 int llc_conn_ac_stop_all_timers(struct sock *sk, struct sk_buff *skb)
1094 {
1095         struct llc_sock *llc = llc_sk(sk);
1096
1097         del_timer(&llc->pf_cycle_timer.timer);
1098         del_timer(&llc->ack_timer.timer);
1099         del_timer(&llc->rej_sent_timer.timer);
1100         del_timer(&llc->busy_state_timer.timer);
1101         llc->ack_must_be_send = 0;
1102         llc->ack_pf = 0;
1103         return 0;
1104 }
1105
1106 int llc_conn_ac_stop_other_timers(struct sock *sk, struct sk_buff *skb)
1107 {
1108         struct llc_sock *llc = llc_sk(sk);
1109
1110         del_timer(&llc->rej_sent_timer.timer);
1111         del_timer(&llc->pf_cycle_timer.timer);
1112         del_timer(&llc->busy_state_timer.timer);
1113         llc->ack_must_be_send = 0;
1114         llc->ack_pf = 0;
1115         return 0;
1116 }
1117
1118 int llc_conn_ac_start_ack_timer(struct sock *sk, struct sk_buff *skb)
1119 {
1120         struct llc_sock *llc = llc_sk(sk);
1121
1122         mod_timer(&llc->ack_timer.timer, jiffies + llc->ack_timer.expire);
1123         return 0;
1124 }
1125
1126 int llc_conn_ac_start_rej_timer(struct sock *sk, struct sk_buff *skb)
1127 {
1128         struct llc_sock *llc = llc_sk(sk);
1129
1130         mod_timer(&llc->rej_sent_timer.timer,
1131                   jiffies + llc->rej_sent_timer.expire);
1132         return 0;
1133 }
1134
1135 int llc_conn_ac_start_ack_tmr_if_not_running(struct sock *sk,
1136                                              struct sk_buff *skb)
1137 {
1138         struct llc_sock *llc = llc_sk(sk);
1139
1140         if (!timer_pending(&llc->ack_timer.timer))
1141                 mod_timer(&llc->ack_timer.timer,
1142                           jiffies + llc->ack_timer.expire);
1143         return 0;
1144 }
1145
1146 int llc_conn_ac_stop_ack_timer(struct sock *sk, struct sk_buff *skb)
1147 {
1148         del_timer(&llc_sk(sk)->ack_timer.timer);
1149         return 0;
1150 }
1151
1152 int llc_conn_ac_stop_p_timer(struct sock *sk, struct sk_buff *skb)
1153 {
1154         struct llc_sock *llc = llc_sk(sk);
1155
1156         del_timer(&llc->pf_cycle_timer.timer);
1157         llc_conn_set_p_flag(sk, 0);
1158         return 0;
1159 }
1160
1161 int llc_conn_ac_stop_rej_timer(struct sock *sk, struct sk_buff *skb)
1162 {
1163         del_timer(&llc_sk(sk)->rej_sent_timer.timer);
1164         return 0;
1165 }
1166
1167 int llc_conn_ac_upd_nr_received(struct sock *sk, struct sk_buff *skb)
1168 {
1169         int acked;
1170         u16 unacked = 0;
1171         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1172         struct llc_sock *llc = llc_sk(sk);
1173
1174         llc->last_nr = PDU_SUPV_GET_Nr(pdu);
1175         acked = llc_conn_remove_acked_pdus(sk, llc->last_nr, &unacked);
1176         /* On loopback we don't queue I frames in unack_pdu_q queue. */
1177         if (acked > 0 || (llc->dev->flags & IFF_LOOPBACK)) {
1178                 llc->retry_count = 0;
1179                 del_timer(&llc->ack_timer.timer);
1180                 if (llc->failed_data_req) {
1181                         /* already, we did not accept data from upper layer
1182                          * (tx_window full or unacceptable state). Now, we
1183                          * can send data and must inform to upper layer.
1184                          */
1185                         llc->failed_data_req = 0;
1186                         llc_conn_ac_data_confirm(sk, skb);
1187                 }
1188                 if (unacked)
1189                         mod_timer(&llc->ack_timer.timer,
1190                                   jiffies + llc->ack_timer.expire);
1191         } else if (llc->failed_data_req) {
1192                 u8 f_bit;
1193
1194                 llc_pdu_decode_pf_bit(skb, &f_bit);
1195                 if (f_bit == 1) {
1196                         llc->failed_data_req = 0;
1197                         llc_conn_ac_data_confirm(sk, skb);
1198                 }
1199         }
1200         return 0;
1201 }
1202
1203 int llc_conn_ac_upd_p_flag(struct sock *sk, struct sk_buff *skb)
1204 {
1205         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1206
1207         if (LLC_PDU_IS_RSP(pdu)) {
1208                 u8 f_bit;
1209
1210                 llc_pdu_decode_pf_bit(skb, &f_bit);
1211                 if (f_bit) {
1212                         llc_conn_set_p_flag(sk, 0);
1213                         llc_conn_ac_stop_p_timer(sk, skb);
1214                 }
1215         }
1216         return 0;
1217 }
1218
1219 int llc_conn_ac_set_data_flag_2(struct sock *sk, struct sk_buff *skb)
1220 {
1221         llc_sk(sk)->data_flag = 2;
1222         return 0;
1223 }
1224
1225 int llc_conn_ac_set_data_flag_0(struct sock *sk, struct sk_buff *skb)
1226 {
1227         llc_sk(sk)->data_flag = 0;
1228         return 0;
1229 }
1230
1231 int llc_conn_ac_set_data_flag_1(struct sock *sk, struct sk_buff *skb)
1232 {
1233         llc_sk(sk)->data_flag = 1;
1234         return 0;
1235 }
1236
1237 int llc_conn_ac_set_data_flag_1_if_data_flag_eq_0(struct sock *sk,
1238                                                   struct sk_buff *skb)
1239 {
1240         if (!llc_sk(sk)->data_flag)
1241                 llc_sk(sk)->data_flag = 1;
1242         return 0;
1243 }
1244
1245 int llc_conn_ac_set_p_flag_0(struct sock *sk, struct sk_buff *skb)
1246 {
1247         llc_conn_set_p_flag(sk, 0);
1248         return 0;
1249 }
1250
1251 static int llc_conn_ac_set_p_flag_1(struct sock *sk, struct sk_buff *skb)
1252 {
1253         llc_conn_set_p_flag(sk, 1);
1254         return 0;
1255 }
1256
1257 int llc_conn_ac_set_remote_busy_0(struct sock *sk, struct sk_buff *skb)
1258 {
1259         llc_sk(sk)->remote_busy_flag = 0;
1260         return 0;
1261 }
1262
1263 int llc_conn_ac_set_cause_flag_0(struct sock *sk, struct sk_buff *skb)
1264 {
1265         llc_sk(sk)->cause_flag = 0;
1266         return 0;
1267 }
1268
1269 int llc_conn_ac_set_cause_flag_1(struct sock *sk, struct sk_buff *skb)
1270 {
1271         llc_sk(sk)->cause_flag = 1;
1272         return 0;
1273 }
1274
1275 int llc_conn_ac_set_retry_cnt_0(struct sock *sk, struct sk_buff *skb)
1276 {
1277         llc_sk(sk)->retry_count = 0;
1278         return 0;
1279 }
1280
1281 int llc_conn_ac_inc_retry_cnt_by_1(struct sock *sk, struct sk_buff *skb)
1282 {
1283         llc_sk(sk)->retry_count++;
1284         return 0;
1285 }
1286
1287 int llc_conn_ac_set_vr_0(struct sock *sk, struct sk_buff *skb)
1288 {
1289         llc_sk(sk)->vR = 0;
1290         return 0;
1291 }
1292
1293 int llc_conn_ac_inc_vr_by_1(struct sock *sk, struct sk_buff *skb)
1294 {
1295         llc_sk(sk)->vR = PDU_GET_NEXT_Vr(llc_sk(sk)->vR);
1296         return 0;
1297 }
1298
1299 int llc_conn_ac_set_vs_0(struct sock *sk, struct sk_buff *skb)
1300 {
1301         llc_sk(sk)->vS = 0;
1302         return 0;
1303 }
1304
1305 int llc_conn_ac_set_vs_nr(struct sock *sk, struct sk_buff *skb)
1306 {
1307         llc_sk(sk)->vS = llc_sk(sk)->last_nr;
1308         return 0;
1309 }
1310
1311 static int llc_conn_ac_inc_vs_by_1(struct sock *sk, struct sk_buff *skb)
1312 {
1313         llc_sk(sk)->vS = (llc_sk(sk)->vS + 1) % LLC_2_SEQ_NBR_MODULO;
1314         return 0;
1315 }
1316
1317 static void llc_conn_tmr_common_cb(unsigned long timeout_data, u8 type)
1318 {
1319         struct sock *sk = (struct sock *)timeout_data;
1320         struct sk_buff *skb = alloc_skb(0, GFP_ATOMIC);
1321
1322         bh_lock_sock(sk);
1323         if (skb) {
1324                 struct llc_conn_state_ev *ev = llc_conn_ev(skb);
1325
1326                 skb_set_owner_r(skb, sk);
1327                 ev->type = type;
1328                 llc_process_tmr_ev(sk, skb);
1329         }
1330         bh_unlock_sock(sk);
1331 }
1332
1333 void llc_conn_pf_cycle_tmr_cb(unsigned long timeout_data)
1334 {
1335         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_P_TMR);
1336 }
1337
1338 void llc_conn_busy_tmr_cb(unsigned long timeout_data)
1339 {
1340         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_BUSY_TMR);
1341 }
1342
1343 void llc_conn_ack_tmr_cb(unsigned long timeout_data)
1344 {
1345         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_ACK_TMR);
1346 }
1347
1348 void llc_conn_rej_tmr_cb(unsigned long timeout_data)
1349 {
1350         llc_conn_tmr_common_cb(timeout_data, LLC_CONN_EV_TYPE_REJ_TMR);
1351 }
1352
1353 int llc_conn_ac_rst_vs(struct sock *sk, struct sk_buff *skb)
1354 {
1355         llc_sk(sk)->X = llc_sk(sk)->vS;
1356         llc_conn_ac_set_vs_nr(sk, skb);
1357         return 0;
1358 }
1359
1360 int llc_conn_ac_upd_vs(struct sock *sk, struct sk_buff *skb)
1361 {
1362         struct llc_pdu_sn *pdu = llc_pdu_sn_hdr(skb);
1363         u8 nr = PDU_SUPV_GET_Nr(pdu);
1364
1365         if (llc_circular_between(llc_sk(sk)->vS, nr, llc_sk(sk)->X))
1366                 llc_conn_ac_set_vs_nr(sk, skb);
1367         return 0;
1368 }
1369
1370 /*
1371  * Non-standard actions; these not contained in IEEE specification; for
1372  * our own usage
1373  */
1374 /**
1375  *      llc_conn_disc - removes connection from SAP list and frees it
1376  *      @sk: closed connection
1377  *      @skb: occurred event
1378  */
1379 int llc_conn_disc(struct sock *sk, struct sk_buff *skb)
1380 {
1381         /* FIXME: this thing seems to want to die */
1382         return 0;
1383 }
1384
1385 /**
1386  *      llc_conn_reset - resets connection
1387  *      @sk : reseting connection.
1388  *      @skb: occurred event.
1389  *
1390  *      Stop all timers, empty all queues and reset all flags.
1391  */
1392 int llc_conn_reset(struct sock *sk, struct sk_buff *skb)
1393 {
1394         llc_sk_reset(sk);
1395         return 0;
1396 }
1397
1398 /**
1399  *      llc_circular_between - designates that b is between a and c or not
1400  *      @a: lower bound
1401  *      @b: element to see if is between a and b
1402  *      @c: upper bound
1403  *
1404  *      This function designates that b is between a and c or not (for example,
1405  *      0 is between 127 and 1). Returns 1 if b is between a and c, 0
1406  *      otherwise.
1407  */
1408 u8 llc_circular_between(u8 a, u8 b, u8 c)
1409 {
1410         b = b - a;
1411         c = c - a;
1412         return b <= c;
1413 }
1414
1415 /**
1416  *      llc_process_tmr_ev - timer backend
1417  *      @sk: active connection
1418  *      @skb: occurred event
1419  *
1420  *      This function is called from timer callback functions. When connection
1421  *      is busy (during sending a data frame) timer expiration event must be
1422  *      queued. Otherwise this event can be sent to connection state machine.
1423  *      Queued events will process by llc_backlog_rcv function after sending
1424  *      data frame.
1425  */
1426 static void llc_process_tmr_ev(struct sock *sk, struct sk_buff *skb)
1427 {
1428         if (llc_sk(sk)->state == LLC_CONN_OUT_OF_SVC) {
1429                 printk(KERN_WARNING "%s: timer called on closed connection\n",
1430                        __FUNCTION__);
1431                 kfree_skb(skb);
1432         } else {
1433                 if (!sock_owned_by_user(sk))
1434                         llc_conn_state_process(sk, skb);
1435                 else {
1436                         llc_set_backlog_type(skb, LLC_EVENT);
1437                         sk_add_backlog(sk, skb);
1438                 }
1439         }
1440 }