1
2/*
3 * ng_lmi.c
4 *
5 * Copyright (c) 1996-1999 Whistle Communications, Inc.
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 * copyright notice above and the following disclaimer of warranties; and
14 * 2. No rights are granted, in any manner or form, to use Whistle
15 * Communications, Inc. trademarks, including the mark "WHISTLE
16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17 * such appears in the above copyright notice or in the software.
18 *
19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35 * OF SUCH DAMAGE.
36 *
37 * Author: Julian Elischer <julian@freebsd.org>
38 *
39 * $FreeBSD: head/sys/netgraph/ng_lmi.c 69922 2000-12-12 18:52:14Z julian $
40 * $Whistle: ng_lmi.c,v 1.38 1999/11/01 09:24:52 julian Exp $
41 */
42
43/*
44 * This node performs the frame relay LMI protocol. It knows how
45 * to do ITU Annex A, ANSI Annex D, and "Group-of-Four" variants
46 * of the protocol.
47 *
48 * A specific protocol can be forced by connecting the corresponding
49 * hook to DLCI 0 or 1023 (as appropriate) of a frame relay link.
50 *
51 * Alternately, this node can do auto-detection of the LMI protocol
52 * by connecting hook "auto0" to DLCI 0 and "auto1023" to DLCI 1023.
53 */
54
55#include <sys/param.h>
56#include <sys/systm.h>
57#include <sys/errno.h>
58#include <sys/kernel.h>
59#include <sys/malloc.h>
60#include <sys/mbuf.h>
61#include <sys/syslog.h>
62#include <netgraph/ng_message.h>
63#include <netgraph/netgraph.h>
64#include <netgraph/ng_lmi.h>
65
66/*
67 * Human readable names for LMI
68 */
69#define NAME_ANNEXA NG_LMI_HOOK_ANNEXA
70#define NAME_ANNEXD NG_LMI_HOOK_ANNEXD
71#define NAME_GROUP4 NG_LMI_HOOK_GROUPOF4
72#define NAME_NONE "None"
73
74#define MAX_DLCIS 128
75#define MAXDLCI 1023
76
77/*
78 * DLCI states
79 */
80#define DLCI_NULL 0
81#define DLCI_UP 1
82#define DLCI_DOWN 2
83
84/*
85 * Any received LMI frame should be at least this long
86 */
87#define LMI_MIN_LENGTH 8 /* XXX verify */
88
89/*
90 * Netgraph node methods and type descriptor
91 */
92static ng_constructor_t nglmi_constructor;
93static ng_rcvmsg_t nglmi_rcvmsg;
94static ng_shutdown_t nglmi_rmnode;
95static ng_newhook_t nglmi_newhook;
96static ng_rcvdata_t nglmi_rcvdata;
97static ng_disconnect_t nglmi_disconnect;
98static int nglmi_checkdata(hook_p hook, struct mbuf *m, meta_p meta);
99
100static struct ng_type typestruct = {
101 NG_VERSION,
102 NG_LMI_NODE_TYPE,
103 NULL,
104 nglmi_constructor,
105 nglmi_rcvmsg,
106 nglmi_rmnode,
107 nglmi_newhook,
108 NULL,
109 NULL,
110 nglmi_rcvdata,
111 nglmi_disconnect,
112 NULL
113};
114NETGRAPH_INIT(lmi, &typestruct);
115
116/*
117 * Info and status per node
118 */
119struct nglmi_softc {
120 node_p node; /* netgraph node */
121 int flags; /* state */
122 int poll_count; /* the count of times for autolmi */
123 int poll_state; /* state of auto detect machine */
124 u_char remote_seq; /* sequence number the remote sent */
125 u_char local_seq; /* last sequence number we sent */
126 u_char protoID; /* 9 for group of 4, 8 otherwise */
127 u_long seq_retries; /* sent this how many time so far */
128 struct callout_handle handle; /* see timeout(9) */
129 int liv_per_full;
130 int liv_rate;
131 int livs;
132 int need_full;
133 hook_p lmi_channel; /* whatever we ended up using */
134 hook_p lmi_annexA;
135 hook_p lmi_annexD;
136 hook_p lmi_group4;
137 hook_p lmi_channel0; /* auto-detect on DLCI 0 */
138 hook_p lmi_channel1023;/* auto-detect on DLCI 1023 */
139 char *protoname; /* cache protocol name */
140 u_char dlci_state[MAXDLCI + 1];
141 int invalidx; /* next dlci's to invalidate */
142};
143typedef struct nglmi_softc *sc_p;
144
145/*
146 * Other internal functions
147 */
148static void LMI_ticker(void *arg);
149static void nglmi_startup_fixed(sc_p sc, hook_p hook);
150static void nglmi_startup_auto(sc_p sc);
151static void nglmi_startup(sc_p sc);
152static void nglmi_inquire(sc_p sc, int full);
153static void ngauto_state_machine(sc_p sc);
154
155/*
156 * Values for 'flags' field
157 * NB: the SCF_CONNECTED flag is set if and only if the timer is running.
158 */
159#define SCF_CONNECTED 0x01 /* connected to something */
160#define SCF_AUTO 0x02 /* we are auto-detecting */
161#define SCF_FIXED 0x04 /* we are fixed from the start */
162
163#define SCF_LMITYPE 0x18 /* mask for determining Annex mode */
164#define SCF_NOLMI 0x00 /* no LMI type selected yet */
165#define SCF_ANNEX_A 0x08 /* running annex A mode */
166#define SCF_ANNEX_D 0x10 /* running annex D mode */
167#define SCF_GROUP4 0x18 /* running group of 4 */
168
169#define SETLMITYPE(sc, annex) \
170do { \
171 (sc)->flags &= ~SCF_LMITYPE; \
172 (sc)->flags |= (annex); \
173} while (0)
174
175#define NOPROTO(sc) (((sc)->flags & SCF_LMITYPE) == SCF_NOLMI)
176#define ANNEXA(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_A)
177#define ANNEXD(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_D)
178#define GROUP4(sc) (((sc)->flags & SCF_LMITYPE) == SCF_GROUP4)
179
180#define LMIPOLLSIZE 3
181#define LMI_PATIENCE 8 /* declare all DLCI DOWN after N LMI failures */
182
183/*
184 * Node constructor
185 */
186static int
187nglmi_constructor(node_p *nodep)
188{
189 sc_p sc;
190 int error = 0;
191
192 MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
193 if (sc == NULL)
194 return (ENOMEM);
195
196 callout_handle_init(&sc->handle);
197 if ((error = ng_make_node_common(&typestruct, nodep))) {
198 FREE(sc, M_NETGRAPH);
199 return (error);
200 }
201 (*nodep)->private = sc;
202 sc->protoname = NAME_NONE;
203 sc->node = *nodep;
204 sc->liv_per_full = NG_LMI_SEQ_PER_FULL; /* make this dynamic */
205 sc->liv_rate = NG_LMI_KEEPALIVE_RATE;
206 return (0);
207}
208
209/*
210 * The LMI channel has a private pointer which is the same as the
211 * node private pointer. The debug channel has a NULL private pointer.
212 */
213static int
214nglmi_newhook(node_p node, hook_p hook, const char *name)
215{
216 sc_p sc = node->private;
217
218 if (strcmp(name, NG_LMI_HOOK_DEBUG) == 0) {
219 hook->private = NULL;
220 return (0);
221 }
222 if (sc->flags & SCF_CONNECTED) {
223 /* already connected, return an error */
224 return (EINVAL);
225 }
226 if (strcmp(name, NG_LMI_HOOK_ANNEXA) == 0) {
227 sc->lmi_annexA = hook;
228 hook->private = node->private;
229 sc->protoID = 8;
230 SETLMITYPE(sc, SCF_ANNEX_A);
231 sc->protoname = NAME_ANNEXA;
232 nglmi_startup_fixed(sc, hook);
233 } else if (strcmp(name, NG_LMI_HOOK_ANNEXD) == 0) {
234 sc->lmi_annexD = hook;
235 hook->private = node->private;
236 sc->protoID = 8;
237 SETLMITYPE(sc, SCF_ANNEX_D);
238 sc->protoname = NAME_ANNEXD;
239 nglmi_startup_fixed(sc, hook);
240 } else if (strcmp(name, NG_LMI_HOOK_GROUPOF4) == 0) {
241 sc->lmi_group4 = hook;
242 hook->private = node->private;
243 sc->protoID = 9;
244 SETLMITYPE(sc, SCF_GROUP4);
245 sc->protoname = NAME_GROUP4;
246 nglmi_startup_fixed(sc, hook);
247 } else if (strcmp(name, NG_LMI_HOOK_AUTO0) == 0) {
248 /* Note this, and if B is already installed, we're complete */
249 sc->lmi_channel0 = hook;
250 sc->protoname = NAME_NONE;
251 hook->private = node->private;
252 if (sc->lmi_channel1023)
253 nglmi_startup_auto(sc);
254 } else if (strcmp(name, NG_LMI_HOOK_AUTO1023) == 0) {
255 /* Note this, and if A is already installed, we're complete */
256 sc->lmi_channel1023 = hook;
257 sc->protoname = NAME_NONE;
258 hook->private = node->private;
259 if (sc->lmi_channel0)
260 nglmi_startup_auto(sc);
261 } else
262 return (EINVAL); /* unknown hook */
263 return (0);
264}
265
266/*
267 * We have just attached to a live (we hope) node.
268 * Fire out a LMI inquiry, and then start up the timers.
269 */
270static void
271LMI_ticker(void *arg)
272{
273 sc_p sc = arg;
274 int s = splnet();
275
276 if (sc->flags & SCF_AUTO) {
277 ngauto_state_machine(sc);
278 sc->handle = timeout(LMI_ticker, sc, NG_LMI_POLL_RATE * hz);
279 } else {
280 if (sc->livs++ >= sc->liv_per_full) {
281 nglmi_inquire(sc, 1);
282 /* sc->livs = 0; *//* do this when we get the answer! */
283 } else {
284 nglmi_inquire(sc, 0);
285 }
286 sc->handle = timeout(LMI_ticker, sc, sc->liv_rate * hz);
287 }
288 splx(s);
289}
290
291static void
292nglmi_startup_fixed(sc_p sc, hook_p hook)
293{
294 sc->flags |= (SCF_FIXED | SCF_CONNECTED);
295 sc->lmi_channel = hook;
296 nglmi_startup(sc);
297}
298
299static void
300nglmi_startup_auto(sc_p sc)
301{
302 sc->flags |= (SCF_AUTO | SCF_CONNECTED);
303 sc->poll_state = 0; /* reset state machine */
304 sc->poll_count = 0;
305 nglmi_startup(sc);
306}
307
308static void
309nglmi_startup(sc_p sc)
310{
311 sc->remote_seq = 0;
312 sc->local_seq = 1;
313 sc->seq_retries = 0;
314 sc->livs = sc->liv_per_full - 1;
315 /* start off the ticker in 1 sec */
316 sc->handle = timeout(LMI_ticker, sc, hz);
317}
318
319#define META_PAD 16
320static void
321nglmi_inquire(sc_p sc, int full)
322{
323 struct mbuf *m;
324 char *cptr, *start;
325 int error;
326 meta_p meta = NULL;
327
328 if (sc->lmi_channel == NULL)
329 return;
330 MGETHDR(m, M_DONTWAIT, MT_DATA);
331 if (m == NULL) {
332 log(LOG_ERR, "nglmi: unable to start up LMI processing\n");
333 return;
334 }
335 m->m_pkthdr.rcvif = NULL;
336 /* Allocate a meta struct (and leave some slop for options to be
337 * added by other modules). */
338 /* MALLOC(meta, meta_p, sizeof( struct ng_meta) + META_PAD,
339 * M_NETGRAPH, M_NOWAIT); */
340 MALLOC(meta, meta_p, sizeof(*meta) + META_PAD, M_NETGRAPH, M_NOWAIT);
341 if (meta != NULL) { /* if it failed, well, it was optional anyhow */
342 meta->used_len = (u_short) sizeof(struct ng_meta);
343 meta->allocated_len
344 = (u_short) sizeof(struct ng_meta) + META_PAD;
345 meta->flags = 0;
346 meta->priority = NG_LMI_LMI_PRIORITY;
347 meta->discardability = -1;
348 }
349 m->m_data += 4; /* leave some room for a header */
350 cptr = start = mtod(m, char *);
351 /* add in the header for an LMI inquiry. */
352 *cptr++ = 0x03; /* UI frame */
353 if (GROUP4(sc))
354 *cptr++ = 0x09; /* proto discriminator */
355 else
356 *cptr++ = 0x08; /* proto discriminator */
357 *cptr++ = 0x00; /* call reference */
358 *cptr++ = 0x75; /* inquiry */
359
360 /* If we are Annex-D, there is this extra thing.. */
361 if (ANNEXD(sc))
362 *cptr++ = 0x95; /* ??? */
363 /* Add a request type */
364 if (ANNEXA(sc))
365 *cptr++ = 0x51; /* report type */
366 else
367 *cptr++ = 0x01; /* report type */
368 *cptr++ = 0x01; /* size = 1 */
369 if (full)
370 *cptr++ = 0x00; /* full */
371 else
372 *cptr++ = 0x01; /* partial */
373
374 /* Add a link verification IE */
375 if (ANNEXA(sc))
376 *cptr++ = 0x53; /* verification IE */
377 else
378 *cptr++ = 0x03; /* verification IE */
379 *cptr++ = 0x02; /* 2 extra bytes */
380 *cptr++ = sc->local_seq;
381 *cptr++ = sc->remote_seq;
382 sc->seq_retries++;
383
384 /* Send it */
385 m->m_len = m->m_pkthdr.len = cptr - start;
386 NG_SEND_DATA(error, sc->lmi_channel, m, meta);
387
388 /* If we've been sending requests for long enough, and there has
389 * been no response, then mark as DOWN, any DLCIs that are UP. */
390 if (sc->seq_retries == LMI_PATIENCE) {
391 int count;
392
393 for (count = 0; count < MAXDLCI; count++)
394 if (sc->dlci_state[count] == DLCI_UP)
395 sc->dlci_state[count] = DLCI_DOWN;
396 }
397}
398
399/*
400 * State machine for LMI auto-detect. The transitions are ordered
401 * to try the more likely possibilities first.
402 */
403static void
404ngauto_state_machine(sc_p sc)
405{
406 if ((sc->poll_count <= 0) || (sc->poll_count > LMIPOLLSIZE)) {
407 /* time to change states in the auto probe machine */
408 /* capture wild values of poll_count while we are at it */
409 sc->poll_count = LMIPOLLSIZE;
410 sc->poll_state++;
411 }
412 switch (sc->poll_state) {
413 case 7:
414 log(LOG_WARNING, "nglmi: no response from exchange\n");
415 default: /* capture bad states */
416 sc->poll_state = 1;
417 case 1:
418 sc->lmi_channel = sc->lmi_channel0;
419 SETLMITYPE(sc, SCF_ANNEX_D);
420 break;
421 case 2:
422 sc->lmi_channel = sc->lmi_channel1023;
423 SETLMITYPE(sc, SCF_ANNEX_D);
424 break;
425 case 3:
426 sc->lmi_channel = sc->lmi_channel0;
427 SETLMITYPE(sc, SCF_ANNEX_A);
428 break;
429 case 4:
430 sc->lmi_channel = sc->lmi_channel1023;
431 SETLMITYPE(sc, SCF_GROUP4);
432 break;
433 case 5:
434 sc->lmi_channel = sc->lmi_channel1023;
435 SETLMITYPE(sc, SCF_ANNEX_A);
436 break;
437 case 6:
438 sc->lmi_channel = sc->lmi_channel0;
439 SETLMITYPE(sc, SCF_GROUP4);
440 break;
441 }
442
443 /* send an inquirey encoded appropriatly */
444 nglmi_inquire(sc, 0);
445 sc->poll_count--;
446}
447
448/*
449 * Receive a netgraph control message.
450 */
451static int
452nglmi_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
453 struct ng_mesg **resp, hook_p lasthook)
454{
455 int error = 0;
456 sc_p sc = node->private;
457
458 switch (msg->header.typecookie) {
459 case NGM_GENERIC_COOKIE:
460 switch (msg->header.cmd) {
461 case NGM_TEXT_STATUS:
462 {
463 char *arg;
464 int pos, count;
465
466 NG_MKRESPONSE(*resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
467 if (*resp == NULL) {
468 error = ENOMEM;
469 break;
470 }
471 arg = (*resp)->data;
472 pos = sprintf(arg, "protocol %s ", sc->protoname);
473 if (sc->flags & SCF_FIXED)
474 pos += sprintf(arg + pos, "fixed\n");
475 else if (sc->flags & SCF_AUTO)
476 pos += sprintf(arg + pos, "auto-detecting\n");
477 else
478 pos += sprintf(arg + pos, "auto on dlci %d\n",
479 (sc->lmi_channel == sc->lmi_channel0) ?
480 0 : 1023);
481 pos += sprintf(arg + pos,
482 "keepalive period: %d seconds\n", sc->liv_rate);
483 pos += sprintf(arg + pos,
484 "unacknowledged keepalives: %ld\n",
485 sc->seq_retries);
486 for (count = 0;
487 ((count <= MAXDLCI)
488 && (pos < (NG_TEXTRESPONSE - 20)));
489 count++) {
490 if (sc->dlci_state[count]) {
491 pos += sprintf(arg + pos,
492 "dlci %d %s\n", count,
493 (sc->dlci_state[count]
494 == DLCI_UP) ? "up" : "down");
495 }
496 }
497 (*resp)->header.arglen = pos + 1;
498 break;
499 }
500 default:
501 error = EINVAL;
502 break;
503 }
504 break;
505 case NGM_LMI_COOKIE:
506 switch (msg->header.cmd) {
507 case NGM_LMI_GET_STATUS:
508 {
509 struct nglmistat *stat;
510 int k;
511
512 NG_MKRESPONSE(*resp, msg, sizeof(*stat), M_NOWAIT);
513 if (!*resp) {
514 error = ENOMEM;
515 break;
516 }
517 stat = (struct nglmistat *) (*resp)->data;
518 strncpy(stat->proto,
519 sc->protoname, sizeof(stat->proto) - 1);
520 strncpy(stat->hook,
521 sc->protoname, sizeof(stat->hook) - 1);
522 stat->autod = !!(sc->flags & SCF_AUTO);
523 stat->fixed = !!(sc->flags & SCF_FIXED);
524 for (k = 0; k <= MAXDLCI; k++) {
525 switch (sc->dlci_state[k]) {
526 case DLCI_UP:
527 stat->up[k / 8] |= (1 << (k % 8));
528 /* fall through */
529 case DLCI_DOWN:
530 stat->seen[k / 8] |= (1 << (k % 8));
531 break;
532 }
533 }
534 break;
535 }
536 default:
537 error = EINVAL;
538 break;
539 }
540 break;
541 default:
542 error = EINVAL;
543 break;
544 }
545 FREE(msg, M_NETGRAPH);
546 return (error);
547}
548
549#define STEPBY(stepsize) \
550 do { \
551 packetlen -= (stepsize); \
552 data += (stepsize); \
553 } while (0)
554
555/*
556 * receive data, and use it to update our status.
557 * Anything coming in on the debug port is discarded.
558 */
559static int
560nglmi_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
561 struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
562{
563 sc_p sc = hook->node->private;
564 u_char *data;
565 unsigned short dlci;
566 u_short packetlen;
567 int resptype_seen = 0;
568 int seq_seen = 0;
569
570 if (hook->private == NULL) {
571 goto drop;
572 }
573 packetlen = m->m_hdr.mh_len;
574
575 /* XXX what if it's more than 1 mbuf? */
576 if ((packetlen > MHLEN) && !(m->m_flags & M_EXT)) {
577 log(LOG_WARNING, "nglmi: packetlen (%d) too big\n", packetlen);
578 goto drop;
579 }
580 if (m->m_len < packetlen && (m = m_pullup(m, packetlen)) == NULL) {
581 log(LOG_WARNING,
582 "nglmi: m_pullup failed for %d bytes\n", packetlen);
583 NG_FREE_META(meta);
584 return (0);
585 }
586 if (nglmi_checkdata(hook, m, meta) == 0)
587 return (0);
588
589 /* pass the first 4 bytes (already checked in the nglmi_checkdata()) */
590 data = mtod(m, u_char *);
591 STEPBY(4);
592
593 /* Now check if there is a 'locking shift'. This is only seen in
594 * Annex D frames. don't bother checking, we already did that. Don't
595 * increment immediatly as it might not be there. */
596 if (ANNEXD(sc))
597 STEPBY(1);
598
599 /* If we get this far we should consider that it is a legitimate
600 * frame and we know what it is. */
601 if (sc->flags & SCF_AUTO) {
602 /* note the hook that this valid channel came from and drop
603 * out of auto probe mode. */
604 if (ANNEXA(sc))
605 sc->protoname = NAME_ANNEXA;
606 else if (ANNEXD(sc))
607 sc->protoname = NAME_ANNEXD;
608 else if (GROUP4(sc))
609 sc->protoname = NAME_GROUP4;
610 else {
611 log(LOG_ERR, "nglmi: No known type\n");
612 goto drop;
613 }
614 sc->lmi_channel = hook;
615 sc->flags &= ~SCF_AUTO;
616 log(LOG_INFO, "nglmi: auto-detected %s LMI on DLCI %d\n",
617 sc->protoname, hook == sc->lmi_channel0 ? 0 : 1023);
618 }
619
620 /* While there is more data in the status packet, keep processing
621 * status items. First make sure there is enough data for the
622 * segment descriptor's length field. */
623 while (packetlen >= 2) {
624 u_int segtype = data[0];
625 u_int segsize = data[1];
626
627 /* Now that we know how long it claims to be, make sure
628 * there is enough data for the next seg. */
629 if (packetlen < segsize + 2)
630 break;
631 switch (segtype) {
632 case 0x01:
633 case 0x51:
634 if (resptype_seen) {
635 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
636 goto nextIE;
637 }
638 resptype_seen++;
639 /* The remote end tells us what kind of response
640 * this is. Only expect a type 0 or 1. if we are a
641 * full status, invalidate a few DLCIs just to see
642 * that they are still ok. */
643 if (segsize != 1)
644 goto nextIE;
645 switch (data[2]) {
646 case 1:
647 /* partial status, do no extra processing */
648 break;
649 case 0:
650 {
651 int count = 0;
652 int idx = sc->invalidx;
653
654 for (count = 0; count < 10; count++) {
655 if (idx > MAXDLCI)
656 idx = 0;
657 if (sc->dlci_state[idx] == DLCI_UP)
658 sc->dlci_state[idx] = DLCI_DOWN;
659 idx++;
660 }
661 sc->invalidx = idx;
662 /* we got and we wanted one. relax
663 * now.. but don't reset to 0 if it
664 * was unrequested. */
665 if (sc->livs > sc->liv_per_full)
666 sc->livs = 0;
667 break;
668 }
669 }
670 break;
671 case 0x03:
672 case 0x53:
673 /* The remote tells us what it thinks the sequence
674 * numbers are. If it's not size 2, it must be a
675 * duplicate to have gotten this far, skip it. */
676 if (seq_seen != 0) /* already seen seq numbers */
677 goto nextIE;
678 if (segsize != 2)
679 goto nextIE;
680 sc->remote_seq = data[2];
681 if (sc->local_seq == data[3]) {
682 sc->local_seq++;
683 sc->seq_retries = 0;
684 /* Note that all 3 Frame protocols seem to
685 * not like 0 as a sequence number. */
686 if (sc->local_seq == 0)
687 sc->local_seq = 1;
688 }
689 break;
690 case 0x07:
691 case 0x57:
692 /* The remote tells us about a DLCI that it knows
693 * about. There may be many of these in a single
694 * status response */
695 switch (segsize) {
696 case 6:/* only on 'group of 4' */
697 dlci = ((u_short) data[2] & 0xff) << 8;
698 dlci |= (data[3] & 0xff);
699 if ((dlci < 1024) && (dlci > 0)) {
700 /* XXX */
701 }
702 break;
703 case 3:
704 dlci = ((u_short) data[2] & 0x3f) << 4;
705 dlci |= ((data[3] & 0x78) >> 3);
706 if ((dlci < 1024) && (dlci > 0)) {
707 /* set up the bottom half of the
708 * support for that dlci if it's not
709 * already been done */
710 /* store this information somewhere */
711 }
712 break;
713 default:
714 goto nextIE;
715 }
716 if (sc->dlci_state[dlci] != DLCI_UP) {
717 /* bring new DLCI to life */
718 /* may do more here some day */
719 if (sc->dlci_state[dlci] != DLCI_DOWN)
720 log(LOG_INFO,
721 "nglmi: DLCI %d became active\n",
722 dlci);
723 sc->dlci_state[dlci] = DLCI_UP;
724 }
725 break;
726 }
727nextIE:
728 STEPBY(segsize + 2);
729 }
730 NG_FREE_DATA(m, meta);
731 return (0);
732
733drop:
734 NG_FREE_DATA(m, meta);
735 return (EINVAL);
736}
737
738/*
739 * Check that a packet is entirely kosha.
740 * return 1 of ok, and 0 if not.
741 * All data is discarded if a 0 is returned.
742 */
743static int
744nglmi_checkdata(hook_p hook, struct mbuf *m, meta_p meta)
745{
746 sc_p sc = hook->node->private;
747 u_char *data;
748 u_short packetlen;
749 unsigned short dlci;
750 u_char type;
751 u_char nextbyte;
752 int seq_seen = 0;
753 int resptype_seen = 0; /* 0 , 1 (partial) or 2 (full) */
754 int highest_dlci = 0;
755
756 packetlen = m->m_hdr.mh_len;
757 data = mtod(m, u_char *);
758 if (*data != 0x03) {
759 log(LOG_WARNING, "nglmi: unexpected value in LMI(%d)\n", 1);
760 goto reject;
761 }
762 STEPBY(1);
763
764 /* look at the protocol ID */
765 nextbyte = *data;
766 if (sc->flags & SCF_AUTO) {
767 SETLMITYPE(sc, SCF_NOLMI); /* start with a clean slate */
768 switch (nextbyte) {
769 case 0x8:
770 sc->protoID = 8;
771 break;
772 case 0x9:
773 SETLMITYPE(sc, SCF_GROUP4);
774 sc->protoID = 9;
775 break;
776 default:
777 log(LOG_WARNING, "nglmi: bad Protocol ID(%d)\n",
778 (int) nextbyte);
779 goto reject;
780 }
781 } else {
782 if (nextbyte != sc->protoID) {
783 log(LOG_WARNING, "nglmi: unexpected Protocol ID(%d)\n",
784 (int) nextbyte);
785 goto reject;
786 }
787 }
788 STEPBY(1);
789
790 /* check call reference (always null in non ISDN frame relay) */
791 if (*data != 0x00) {
792 log(LOG_WARNING, "nglmi: unexpected Call Reference (0x%x)\n",
793 data[-1]);
794 goto reject;
795 }
796 STEPBY(1);
797
798 /* check message type */
799 switch ((type = *data)) {
800 case 0x75: /* Status enquiry */
801 log(LOG_WARNING, "nglmi: unexpected message type(0x%x)\n",
802 data[-1]);
803 goto reject;
804 case 0x7D: /* Status message */
805 break;
806 default:
807 log(LOG_WARNING,
808 "nglmi: unexpected msg type(0x%x) \n", (int) type);
809 goto reject;
810 }
811 STEPBY(1);
812
813 /* Now check if there is a 'locking shift'. This is only seen in
814 * Annex D frames. Don't increment immediately as it might not be
815 * there. */
816 nextbyte = *data;
817 if (sc->flags & SCF_AUTO) {
818 if (!(GROUP4(sc))) {
819 if (nextbyte == 0x95) {
820 SETLMITYPE(sc, SCF_ANNEX_D);
821 STEPBY(1);
822 } else
823 SETLMITYPE(sc, SCF_ANNEX_A);
824 } else if (nextbyte == 0x95) {
825 log(LOG_WARNING, "nglmi: locking shift seen in G4\n");
826 goto reject;
827 }
828 } else {
829 if (ANNEXD(sc)) {
830 if (*data == 0x95)
831 STEPBY(1);
832 else {
833 log(LOG_WARNING,
834 "nglmi: locking shift missing\n");
835 goto reject;
836 }
837 } else if (*data == 0x95) {
838 log(LOG_WARNING, "nglmi: locking shift seen\n");
839 goto reject;
840 }
841 }
842
843 /* While there is more data in the status packet, keep processing
844 * status items. First make sure there is enough data for the
845 * segment descriptor's length field. */
846 while (packetlen >= 2) {
847 u_int segtype = data[0];
848 u_int segsize = data[1];
849
850 /* Now that we know how long it claims to be, make sure
851 * there is enough data for the next seg. */
852 if (packetlen < (segsize + 2)) {
853 log(LOG_WARNING, "nglmi: IE longer than packet\n");
854 break;
855 }
856 switch (segtype) {
857 case 0x01:
858 case 0x51:
859 /* According to MCI's HP analyser, we should just
860 * ignore if there is mor ethan one of these (?). */
861 if (resptype_seen) {
862 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
863 goto nextIE;
864 }
865 if (segsize != 1) {
866 log(LOG_WARNING, "nglmi: MSGTYPE wrong size\n");
867 goto reject;
868 }
869 /* The remote end tells us what kind of response
870 * this is. Only expect a type 0 or 1. if it was a
871 * full (type 0) check we just asked for a type
872 * full. */
873 switch (data[2]) {
874 case 1:/* partial */
875 if (sc->livs > sc->liv_per_full) {
876 log(LOG_WARNING,
877 "nglmi: LIV when FULL expected\n");
878 goto reject; /* need full */
879 }
880 resptype_seen = 1;
881 break;
882 case 0:/* full */
883 /* Full response is always acceptable */
884 resptype_seen = 2;
885 break;
886 default:
887 log(LOG_WARNING,
888 "nglmi: Unknown report type %d\n", data[2]);
889 goto reject;
890 }
891 break;
892 case 0x03:
893 case 0x53:
894 /* The remote tells us what it thinks the sequence
895 * numbers are. I would have thought that there
896 * needs to be one and only one of these, but MCI
897 * want us to just ignore extras. (?) */
898 if (resptype_seen == 0) {
899 log(LOG_WARNING, "nglmi: no TYPE before SEQ\n");
900 goto reject;
901 }
902 if (seq_seen != 0) /* already seen seq numbers */
903 goto nextIE;
904 if (segsize != 2) {
905 log(LOG_WARNING, "nglmi: bad SEQ sts size\n");
906 goto reject;
907 }
908 if (sc->local_seq != data[3]) {
909 log(LOG_WARNING, "nglmi: unexpected SEQ\n");
910 goto reject;
911 }
912 seq_seen = 1;
913 break;
914 case 0x07:
915 case 0x57:
916 /* The remote tells us about a DLCI that it knows
917 * about. There may be many of these in a single
918 * status response */
919 if (seq_seen != 1) { /* already seen seq numbers? */
920 log(LOG_WARNING,
921 "nglmi: No sequence before DLCI\n");
922 goto reject;
923 }
924 if (resptype_seen != 2) { /* must be full */
925 log(LOG_WARNING,
926 "nglmi: No resp type before DLCI\n");
927 goto reject;
928 }
929 if (GROUP4(sc)) {
930 if (segsize != 6) {
931 log(LOG_WARNING,
932 "nglmi: wrong IE segsize\n");
933 goto reject;
934 }
935 dlci = ((u_short) data[2] & 0xff) << 8;
936 dlci |= (data[3] & 0xff);
937 } else {
938 if (segsize != 3) {
939 log(LOG_WARNING,
940 "nglmi: DLCI headersize of %d"
941 " not supported\n", segsize - 1);
942 goto reject;
943 }
944 dlci = ((u_short) data[2] & 0x3f) << 4;
945 dlci |= ((data[3] & 0x78) >> 3);
946 }
947 /* async can only have one of these */
948#if 0 /* async not yet accepted */
949 if (async && highest_dlci) {
950 log(LOG_WARNING,
951 "nglmi: Async with > 1 DLCI\n");
952 goto reject;
953 }
954#endif
955 /* Annex D says these will always be Ascending, but
956 * the HP test for G4 says we should accept
957 * duplicates, so for now allow that. ( <= vs. < ) */
958#if 0
959 /* MCI tests want us to accept out of order for AnxD */
960 if ((!GROUP4(sc)) && (dlci < highest_dlci)) {
961 /* duplicate or mis-ordered dlci */
962 /* (spec says they will increase in number) */
963 log(LOG_WARNING, "nglmi: DLCI out of order\n");
964 goto reject;
965 }
966#endif
967 if (dlci > 1023) {
968 log(LOG_WARNING, "nglmi: DLCI out of range\n");
969 goto reject;
970 }
971 highest_dlci = dlci;
972 break;
973 default:
974 log(LOG_WARNING,
975 "nglmi: unknown LMI segment type %d\n", segtype);
976 }
977nextIE:
978 STEPBY(segsize + 2);
979 }
980 if (packetlen != 0) { /* partial junk at end? */
981 log(LOG_WARNING,
982 "nglmi: %d bytes extra at end of packet\n", packetlen);
983 goto print;
984 }
985 if (resptype_seen == 0) {
986 log(LOG_WARNING, "nglmi: No response type seen\n");
987 goto reject; /* had no response type */
988 }
989 if (seq_seen == 0) {
990 log(LOG_WARNING, "nglmi: No sequence numbers seen\n");
991 goto reject; /* had no sequence numbers */
992 }
993 return (1);
994
995print:
996 {
997 int i, j, k, pos;
998 char buf[100];
999 int loc;
1000 u_char *bp = mtod(m, u_char *);
1001
1002 k = i = 0;
1003 loc = (m->m_hdr.mh_len - packetlen);
1004 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
1005 while (k < m->m_hdr.mh_len) {
1006 pos = 0;
1007 j = 0;
1008 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1009 pos += sprintf(buf + pos, "%c%02x",
1010 ((loc == k) ? '>' : ' '),
1011 bp[k]);
1012 k++;
1013 }
1014 if (i == 0)
1015 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1016 else
1017 log(LOG_WARNING, "%04d :%s\n", k, buf);
1018 i++;
1019 }
1020 }
1021 return (1);
1022reject:
1023 {
1024 int i, j, k, pos;
1025 char buf[100];
1026 int loc;
1027 u_char *bp = mtod(m, u_char *);
1028
1029 k = i = 0;
1030 loc = (m->m_hdr.mh_len - packetlen);
1031 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
1032 while (k < m->m_hdr.mh_len) {
1033 pos = 0;
1034 j = 0;
1035 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1036 pos += sprintf(buf + pos, "%c%02x",
1037 ((loc == k) ? '>' : ' '),
1038 bp[k]);
1039 k++;
1040 }
1041 if (i == 0)
1042 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1043 else
1044 log(LOG_WARNING, "%04d :%s\n", k, buf);
1045 i++;
1046 }
1047 }
1048 NG_FREE_DATA(m, meta);
1049 return (0);
1050}
1051
1052/*
1053 * Do local shutdown processing..
1054 * Cut any remaining links and free our local resources.
1055 */
1056static int
1057nglmi_rmnode(node_p node)
1058{
1059 const sc_p sc = node->private;
1060
1061 node->flags |= NG_INVALID;
1062 ng_cutlinks(node);
1063 ng_unname(node);
1064 node->private = NULL;
1065 ng_unref(sc->node);
1066 FREE(sc, M_NETGRAPH);
1067 return (0);
1068}
1069
1070/*
1071 * Hook disconnection
1072 * For this type, removal of any link except "debug" destroys the node.
1073 */
1074static int
1075nglmi_disconnect(hook_p hook)
1076{
1077 const sc_p sc = hook->node->private;
1078
1079 /* OK to remove debug hook(s) */
1080 if (hook->private == NULL)
1081 return (0);
1082
1083 /* Stop timer if it's currently active */
1084 if (sc->flags & SCF_CONNECTED)
1085 untimeout(LMI_ticker, sc, sc->handle);
1086
1087 /* Self-destruct */
1088 ng_rmnode(hook->node);
1089 return (0);
1090}
1091