FreeBSD/Linux Kernel Cross Reference
sys/netgraph/ng_lmi.c
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: releng/5.0/sys/netgraph/ng_lmi.c 97897 2002-06-05 23:35:31Z archie $
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 */
92 static ng_constructor_t nglmi_constructor;
93 static ng_rcvmsg_t nglmi_rcvmsg;
94 static ng_shutdown_t nglmi_shutdown;
95 static ng_newhook_t nglmi_newhook;
96 static ng_rcvdata_t nglmi_rcvdata;
97 static ng_disconnect_t nglmi_disconnect;
98 static int nglmi_checkdata(hook_p hook, struct mbuf *m);
99
100 static struct ng_type typestruct = {
101 NG_ABI_VERSION,
102 NG_LMI_NODE_TYPE,
103 NULL,
104 nglmi_constructor,
105 nglmi_rcvmsg,
106 nglmi_shutdown,
107 nglmi_newhook,
108 NULL,
109 NULL,
110 nglmi_rcvdata,
111 nglmi_disconnect,
112 NULL
113 };
114 NETGRAPH_INIT(lmi, &typestruct);
115
116 /*
117 * Info and status per node
118 */
119 struct 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 };
143 typedef struct nglmi_softc *sc_p;
144
145 /*
146 * Other internal functions
147 */
148 static void LMI_ticker(void *arg);
149 static void nglmi_startup_fixed(sc_p sc, hook_p hook);
150 static void nglmi_startup_auto(sc_p sc);
151 static void nglmi_startup(sc_p sc);
152 static void nglmi_inquire(sc_p sc, int full);
153 static 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) \
170 do { \
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 */
186 static int
187 nglmi_constructor(node_p node)
188 {
189 sc_p sc;
190
191 MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
192 if (sc == NULL)
193 return (ENOMEM);
194 callout_handle_init(&sc->handle);
195 NG_NODE_SET_PRIVATE(node, sc);
196 sc->protoname = NAME_NONE;
197 sc->node = node;
198 sc->liv_per_full = NG_LMI_SEQ_PER_FULL; /* make this dynamic */
199 sc->liv_rate = NG_LMI_KEEPALIVE_RATE;
200 return (0);
201 }
202
203 /*
204 * The LMI channel has a private pointer which is the same as the
205 * node private pointer. The debug channel has a NULL private pointer.
206 */
207 static int
208 nglmi_newhook(node_p node, hook_p hook, const char *name)
209 {
210 sc_p sc = NG_NODE_PRIVATE(node);
211
212 if (strcmp(name, NG_LMI_HOOK_DEBUG) == 0) {
213 NG_HOOK_SET_PRIVATE(hook, NULL);
214 return (0);
215 }
216 if (sc->flags & SCF_CONNECTED) {
217 /* already connected, return an error */
218 return (EINVAL);
219 }
220 if (strcmp(name, NG_LMI_HOOK_ANNEXA) == 0) {
221 sc->lmi_annexA = hook;
222 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
223 sc->protoID = 8;
224 SETLMITYPE(sc, SCF_ANNEX_A);
225 sc->protoname = NAME_ANNEXA;
226 nglmi_startup_fixed(sc, hook);
227 } else if (strcmp(name, NG_LMI_HOOK_ANNEXD) == 0) {
228 sc->lmi_annexD = hook;
229 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
230 sc->protoID = 8;
231 SETLMITYPE(sc, SCF_ANNEX_D);
232 sc->protoname = NAME_ANNEXD;
233 nglmi_startup_fixed(sc, hook);
234 } else if (strcmp(name, NG_LMI_HOOK_GROUPOF4) == 0) {
235 sc->lmi_group4 = hook;
236 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
237 sc->protoID = 9;
238 SETLMITYPE(sc, SCF_GROUP4);
239 sc->protoname = NAME_GROUP4;
240 nglmi_startup_fixed(sc, hook);
241 } else if (strcmp(name, NG_LMI_HOOK_AUTO0) == 0) {
242 /* Note this, and if B is already installed, we're complete */
243 sc->lmi_channel0 = hook;
244 sc->protoname = NAME_NONE;
245 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
246 if (sc->lmi_channel1023)
247 nglmi_startup_auto(sc);
248 } else if (strcmp(name, NG_LMI_HOOK_AUTO1023) == 0) {
249 /* Note this, and if A is already installed, we're complete */
250 sc->lmi_channel1023 = hook;
251 sc->protoname = NAME_NONE;
252 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
253 if (sc->lmi_channel0)
254 nglmi_startup_auto(sc);
255 } else
256 return (EINVAL); /* unknown hook */
257 return (0);
258 }
259
260 /*
261 * We have just attached to a live (we hope) node.
262 * Fire out a LMI inquiry, and then start up the timers.
263 */
264 static void
265 LMI_ticker(void *arg)
266 {
267 sc_p sc = arg;
268 int s = splnet();
269
270 if (sc->flags & SCF_AUTO) {
271 ngauto_state_machine(sc);
272 sc->handle = timeout(LMI_ticker, sc, NG_LMI_POLL_RATE * hz);
273 } else {
274 if (sc->livs++ >= sc->liv_per_full) {
275 nglmi_inquire(sc, 1);
276 /* sc->livs = 0; *//* do this when we get the answer! */
277 } else {
278 nglmi_inquire(sc, 0);
279 }
280 sc->handle = timeout(LMI_ticker, sc, sc->liv_rate * hz);
281 }
282 splx(s);
283 }
284
285 static void
286 nglmi_startup_fixed(sc_p sc, hook_p hook)
287 {
288 sc->flags |= (SCF_FIXED | SCF_CONNECTED);
289 sc->lmi_channel = hook;
290 nglmi_startup(sc);
291 }
292
293 static void
294 nglmi_startup_auto(sc_p sc)
295 {
296 sc->flags |= (SCF_AUTO | SCF_CONNECTED);
297 sc->poll_state = 0; /* reset state machine */
298 sc->poll_count = 0;
299 nglmi_startup(sc);
300 }
301
302 static void
303 nglmi_startup(sc_p sc)
304 {
305 sc->remote_seq = 0;
306 sc->local_seq = 1;
307 sc->seq_retries = 0;
308 sc->livs = sc->liv_per_full - 1;
309 /* start off the ticker in 1 sec */
310 sc->handle = timeout(LMI_ticker, sc, hz);
311 }
312
313 #define META_PAD 16
314 static void
315 nglmi_inquire(sc_p sc, int full)
316 {
317 struct mbuf *m;
318 char *cptr, *start;
319 int error;
320 meta_p meta = NULL;
321
322 if (sc->lmi_channel == NULL)
323 return;
324 MGETHDR(m, M_DONTWAIT, MT_DATA);
325 if (m == NULL) {
326 log(LOG_ERR, "nglmi: unable to start up LMI processing\n");
327 return;
328 }
329 m->m_pkthdr.rcvif = NULL;
330 /* Allocate a meta struct (and leave some slop for options to be
331 * added by other modules). */
332 MALLOC(meta, meta_p, sizeof(*meta) + META_PAD, M_NETGRAPH_META, M_NOWAIT);
333 if (meta != NULL) { /* if it failed, well, it was optional anyhow */
334 meta->used_len = (u_short) sizeof(struct ng_meta);
335 meta->allocated_len
336 = (u_short) sizeof(struct ng_meta) + META_PAD;
337 meta->flags = 0;
338 meta->priority = NG_LMI_LMI_PRIORITY;
339 meta->discardability = -1;
340 }
341 m->m_data += 4; /* leave some room for a header */
342 cptr = start = mtod(m, char *);
343 /* add in the header for an LMI inquiry. */
344 *cptr++ = 0x03; /* UI frame */
345 if (GROUP4(sc))
346 *cptr++ = 0x09; /* proto discriminator */
347 else
348 *cptr++ = 0x08; /* proto discriminator */
349 *cptr++ = 0x00; /* call reference */
350 *cptr++ = 0x75; /* inquiry */
351
352 /* If we are Annex-D, there is this extra thing.. */
353 if (ANNEXD(sc))
354 *cptr++ = 0x95; /* ??? */
355 /* Add a request type */
356 if (ANNEXA(sc))
357 *cptr++ = 0x51; /* report type */
358 else
359 *cptr++ = 0x01; /* report type */
360 *cptr++ = 0x01; /* size = 1 */
361 if (full)
362 *cptr++ = 0x00; /* full */
363 else
364 *cptr++ = 0x01; /* partial */
365
366 /* Add a link verification IE */
367 if (ANNEXA(sc))
368 *cptr++ = 0x53; /* verification IE */
369 else
370 *cptr++ = 0x03; /* verification IE */
371 *cptr++ = 0x02; /* 2 extra bytes */
372 *cptr++ = sc->local_seq;
373 *cptr++ = sc->remote_seq;
374 sc->seq_retries++;
375
376 /* Send it */
377 m->m_len = m->m_pkthdr.len = cptr - start;
378 NG_SEND_DATA(error, sc->lmi_channel, m, meta);
379
380 /* If we've been sending requests for long enough, and there has
381 * been no response, then mark as DOWN, any DLCIs that are UP. */
382 if (sc->seq_retries == LMI_PATIENCE) {
383 int count;
384
385 for (count = 0; count < MAXDLCI; count++)
386 if (sc->dlci_state[count] == DLCI_UP)
387 sc->dlci_state[count] = DLCI_DOWN;
388 }
389 }
390
391 /*
392 * State machine for LMI auto-detect. The transitions are ordered
393 * to try the more likely possibilities first.
394 */
395 static void
396 ngauto_state_machine(sc_p sc)
397 {
398 if ((sc->poll_count <= 0) || (sc->poll_count > LMIPOLLSIZE)) {
399 /* time to change states in the auto probe machine */
400 /* capture wild values of poll_count while we are at it */
401 sc->poll_count = LMIPOLLSIZE;
402 sc->poll_state++;
403 }
404 switch (sc->poll_state) {
405 case 7:
406 log(LOG_WARNING, "nglmi: no response from exchange\n");
407 default: /* capture bad states */
408 sc->poll_state = 1;
409 case 1:
410 sc->lmi_channel = sc->lmi_channel0;
411 SETLMITYPE(sc, SCF_ANNEX_D);
412 break;
413 case 2:
414 sc->lmi_channel = sc->lmi_channel1023;
415 SETLMITYPE(sc, SCF_ANNEX_D);
416 break;
417 case 3:
418 sc->lmi_channel = sc->lmi_channel0;
419 SETLMITYPE(sc, SCF_ANNEX_A);
420 break;
421 case 4:
422 sc->lmi_channel = sc->lmi_channel1023;
423 SETLMITYPE(sc, SCF_GROUP4);
424 break;
425 case 5:
426 sc->lmi_channel = sc->lmi_channel1023;
427 SETLMITYPE(sc, SCF_ANNEX_A);
428 break;
429 case 6:
430 sc->lmi_channel = sc->lmi_channel0;
431 SETLMITYPE(sc, SCF_GROUP4);
432 break;
433 }
434
435 /* send an inquirey encoded appropriatly */
436 nglmi_inquire(sc, 0);
437 sc->poll_count--;
438 }
439
440 /*
441 * Receive a netgraph control message.
442 */
443 static int
444 nglmi_rcvmsg(node_p node, item_p item, hook_p lasthook)
445 {
446 sc_p sc = NG_NODE_PRIVATE(node);
447 struct ng_mesg *resp = NULL;
448 int error = 0;
449 struct ng_mesg *msg;
450
451 NGI_GET_MSG(item, msg);
452 switch (msg->header.typecookie) {
453 case NGM_GENERIC_COOKIE:
454 switch (msg->header.cmd) {
455 case NGM_TEXT_STATUS:
456 {
457 char *arg;
458 int pos, count;
459
460 NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
461 if (resp == NULL) {
462 error = ENOMEM;
463 break;
464 }
465 arg = resp->data;
466 pos = sprintf(arg, "protocol %s ", sc->protoname);
467 if (sc->flags & SCF_FIXED)
468 pos += sprintf(arg + pos, "fixed\n");
469 else if (sc->flags & SCF_AUTO)
470 pos += sprintf(arg + pos, "auto-detecting\n");
471 else
472 pos += sprintf(arg + pos, "auto on dlci %d\n",
473 (sc->lmi_channel == sc->lmi_channel0) ?
474 0 : 1023);
475 pos += sprintf(arg + pos,
476 "keepalive period: %d seconds\n", sc->liv_rate);
477 pos += sprintf(arg + pos,
478 "unacknowledged keepalives: %ld\n",
479 sc->seq_retries);
480 for (count = 0;
481 ((count <= MAXDLCI)
482 && (pos < (NG_TEXTRESPONSE - 20)));
483 count++) {
484 if (sc->dlci_state[count]) {
485 pos += sprintf(arg + pos,
486 "dlci %d %s\n", count,
487 (sc->dlci_state[count]
488 == DLCI_UP) ? "up" : "down");
489 }
490 }
491 resp->header.arglen = pos + 1;
492 break;
493 }
494 default:
495 error = EINVAL;
496 break;
497 }
498 break;
499 case NGM_LMI_COOKIE:
500 switch (msg->header.cmd) {
501 case NGM_LMI_GET_STATUS:
502 {
503 struct nglmistat *stat;
504 int k;
505
506 NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
507 if (!resp) {
508 error = ENOMEM;
509 break;
510 }
511 stat = (struct nglmistat *) resp->data;
512 strncpy(stat->proto,
513 sc->protoname, sizeof(stat->proto) - 1);
514 strncpy(stat->hook,
515 sc->protoname, sizeof(stat->hook) - 1);
516 stat->autod = !!(sc->flags & SCF_AUTO);
517 stat->fixed = !!(sc->flags & SCF_FIXED);
518 for (k = 0; k <= MAXDLCI; k++) {
519 switch (sc->dlci_state[k]) {
520 case DLCI_UP:
521 stat->up[k / 8] |= (1 << (k % 8));
522 /* fall through */
523 case DLCI_DOWN:
524 stat->seen[k / 8] |= (1 << (k % 8));
525 break;
526 }
527 }
528 break;
529 }
530 default:
531 error = EINVAL;
532 break;
533 }
534 break;
535 default:
536 error = EINVAL;
537 break;
538 }
539
540 NG_RESPOND_MSG(error, node, item, resp);
541 NG_FREE_MSG(msg);
542 return (error);
543 }
544
545 #define STEPBY(stepsize) \
546 do { \
547 packetlen -= (stepsize); \
548 data += (stepsize); \
549 } while (0)
550
551 /*
552 * receive data, and use it to update our status.
553 * Anything coming in on the debug port is discarded.
554 */
555 static int
556 nglmi_rcvdata(hook_p hook, item_p item)
557 {
558 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
559 const u_char *data;
560 unsigned short dlci;
561 u_short packetlen;
562 int resptype_seen = 0;
563 int seq_seen = 0;
564 struct mbuf *m;
565
566 NGI_GET_M(item, m);
567 NG_FREE_ITEM(item);
568 if (NG_HOOK_PRIVATE(hook) == NULL) {
569 goto drop;
570 }
571 packetlen = m->m_hdr.mh_len;
572
573 /* XXX what if it's more than 1 mbuf? */
574 if ((packetlen > MHLEN) && !(m->m_flags & M_EXT)) {
575 log(LOG_WARNING, "nglmi: packetlen (%d) too big\n", packetlen);
576 goto drop;
577 }
578 if (m->m_len < packetlen && (m = m_pullup(m, packetlen)) == NULL) {
579 log(LOG_WARNING,
580 "nglmi: m_pullup failed for %d bytes\n", packetlen);
581 return (0);
582 }
583 if (nglmi_checkdata(hook, m) == 0)
584 return (0);
585
586 /* pass the first 4 bytes (already checked in the nglmi_checkdata()) */
587 data = mtod(m, const u_char *);
588 STEPBY(4);
589
590 /* Now check if there is a 'locking shift'. This is only seen in
591 * Annex D frames. don't bother checking, we already did that. Don't
592 * increment immediatly as it might not be there. */
593 if (ANNEXD(sc))
594 STEPBY(1);
595
596 /* If we get this far we should consider that it is a legitimate
597 * frame and we know what it is. */
598 if (sc->flags & SCF_AUTO) {
599 /* note the hook that this valid channel came from and drop
600 * out of auto probe mode. */
601 if (ANNEXA(sc))
602 sc->protoname = NAME_ANNEXA;
603 else if (ANNEXD(sc))
604 sc->protoname = NAME_ANNEXD;
605 else if (GROUP4(sc))
606 sc->protoname = NAME_GROUP4;
607 else {
608 log(LOG_ERR, "nglmi: No known type\n");
609 goto drop;
610 }
611 sc->lmi_channel = hook;
612 sc->flags &= ~SCF_AUTO;
613 log(LOG_INFO, "nglmi: auto-detected %s LMI on DLCI %d\n",
614 sc->protoname, hook == sc->lmi_channel0 ? 0 : 1023);
615 }
616
617 /* While there is more data in the status packet, keep processing
618 * status items. First make sure there is enough data for the
619 * segment descriptor's length field. */
620 while (packetlen >= 2) {
621 u_int segtype = data[0];
622 u_int segsize = data[1];
623
624 /* Now that we know how long it claims to be, make sure
625 * there is enough data for the next seg. */
626 if (packetlen < segsize + 2)
627 break;
628 switch (segtype) {
629 case 0x01:
630 case 0x51:
631 if (resptype_seen) {
632 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
633 goto nextIE;
634 }
635 resptype_seen++;
636 /* The remote end tells us what kind of response
637 * this is. Only expect a type 0 or 1. if we are a
638 * full status, invalidate a few DLCIs just to see
639 * that they are still ok. */
640 if (segsize != 1)
641 goto nextIE;
642 switch (data[2]) {
643 case 1:
644 /* partial status, do no extra processing */
645 break;
646 case 0:
647 {
648 int count = 0;
649 int idx = sc->invalidx;
650
651 for (count = 0; count < 10; count++) {
652 if (idx > MAXDLCI)
653 idx = 0;
654 if (sc->dlci_state[idx] == DLCI_UP)
655 sc->dlci_state[idx] = DLCI_DOWN;
656 idx++;
657 }
658 sc->invalidx = idx;
659 /* we got and we wanted one. relax
660 * now.. but don't reset to 0 if it
661 * was unrequested. */
662 if (sc->livs > sc->liv_per_full)
663 sc->livs = 0;
664 break;
665 }
666 }
667 break;
668 case 0x03:
669 case 0x53:
670 /* The remote tells us what it thinks the sequence
671 * numbers are. If it's not size 2, it must be a
672 * duplicate to have gotten this far, skip it. */
673 if (seq_seen != 0) /* already seen seq numbers */
674 goto nextIE;
675 if (segsize != 2)
676 goto nextIE;
677 sc->remote_seq = data[2];
678 if (sc->local_seq == data[3]) {
679 sc->local_seq++;
680 sc->seq_retries = 0;
681 /* Note that all 3 Frame protocols seem to
682 * not like 0 as a sequence number. */
683 if (sc->local_seq == 0)
684 sc->local_seq = 1;
685 }
686 break;
687 case 0x07:
688 case 0x57:
689 /* The remote tells us about a DLCI that it knows
690 * about. There may be many of these in a single
691 * status response */
692 switch (segsize) {
693 case 6:/* only on 'group of 4' */
694 dlci = ((u_short) data[2] & 0xff) << 8;
695 dlci |= (data[3] & 0xff);
696 if ((dlci < 1024) && (dlci > 0)) {
697 /* XXX */
698 }
699 break;
700 case 3:
701 dlci = ((u_short) data[2] & 0x3f) << 4;
702 dlci |= ((data[3] & 0x78) >> 3);
703 if ((dlci < 1024) && (dlci > 0)) {
704 /* set up the bottom half of the
705 * support for that dlci if it's not
706 * already been done */
707 /* store this information somewhere */
708 }
709 break;
710 default:
711 goto nextIE;
712 }
713 if (sc->dlci_state[dlci] != DLCI_UP) {
714 /* bring new DLCI to life */
715 /* may do more here some day */
716 if (sc->dlci_state[dlci] != DLCI_DOWN)
717 log(LOG_INFO,
718 "nglmi: DLCI %d became active\n",
719 dlci);
720 sc->dlci_state[dlci] = DLCI_UP;
721 }
722 break;
723 }
724 nextIE:
725 STEPBY(segsize + 2);
726 }
727 NG_FREE_M(m);
728 return (0);
729
730 drop:
731 NG_FREE_M(m);
732 return (EINVAL);
733 }
734
735 /*
736 * Check that a packet is entirely kosha.
737 * return 1 of ok, and 0 if not.
738 * All data is discarded if a 0 is returned.
739 */
740 static int
741 nglmi_checkdata(hook_p hook, struct mbuf *m)
742 {
743 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
744 const u_char *data;
745 u_short packetlen;
746 unsigned short dlci;
747 u_char type;
748 u_char nextbyte;
749 int seq_seen = 0;
750 int resptype_seen = 0; /* 0 , 1 (partial) or 2 (full) */
751 int highest_dlci = 0;
752
753 packetlen = m->m_hdr.mh_len;
754 data = mtod(m, const u_char *);
755 if (*data != 0x03) {
756 log(LOG_WARNING, "nglmi: unexpected value in LMI(%d)\n", 1);
757 goto reject;
758 }
759 STEPBY(1);
760
761 /* look at the protocol ID */
762 nextbyte = *data;
763 if (sc->flags & SCF_AUTO) {
764 SETLMITYPE(sc, SCF_NOLMI); /* start with a clean slate */
765 switch (nextbyte) {
766 case 0x8:
767 sc->protoID = 8;
768 break;
769 case 0x9:
770 SETLMITYPE(sc, SCF_GROUP4);
771 sc->protoID = 9;
772 break;
773 default:
774 log(LOG_WARNING, "nglmi: bad Protocol ID(%d)\n",
775 (int) nextbyte);
776 goto reject;
777 }
778 } else {
779 if (nextbyte != sc->protoID) {
780 log(LOG_WARNING, "nglmi: unexpected Protocol ID(%d)\n",
781 (int) nextbyte);
782 goto reject;
783 }
784 }
785 STEPBY(1);
786
787 /* check call reference (always null in non ISDN frame relay) */
788 if (*data != 0x00) {
789 log(LOG_WARNING, "nglmi: unexpected Call Reference (0x%x)\n",
790 data[-1]);
791 goto reject;
792 }
793 STEPBY(1);
794
795 /* check message type */
796 switch ((type = *data)) {
797 case 0x75: /* Status enquiry */
798 log(LOG_WARNING, "nglmi: unexpected message type(0x%x)\n",
799 data[-1]);
800 goto reject;
801 case 0x7D: /* Status message */
802 break;
803 default:
804 log(LOG_WARNING,
805 "nglmi: unexpected msg type(0x%x) \n", (int) type);
806 goto reject;
807 }
808 STEPBY(1);
809
810 /* Now check if there is a 'locking shift'. This is only seen in
811 * Annex D frames. Don't increment immediately as it might not be
812 * there. */
813 nextbyte = *data;
814 if (sc->flags & SCF_AUTO) {
815 if (!(GROUP4(sc))) {
816 if (nextbyte == 0x95) {
817 SETLMITYPE(sc, SCF_ANNEX_D);
818 STEPBY(1);
819 } else
820 SETLMITYPE(sc, SCF_ANNEX_A);
821 } else if (nextbyte == 0x95) {
822 log(LOG_WARNING, "nglmi: locking shift seen in G4\n");
823 goto reject;
824 }
825 } else {
826 if (ANNEXD(sc)) {
827 if (*data == 0x95)
828 STEPBY(1);
829 else {
830 log(LOG_WARNING,
831 "nglmi: locking shift missing\n");
832 goto reject;
833 }
834 } else if (*data == 0x95) {
835 log(LOG_WARNING, "nglmi: locking shift seen\n");
836 goto reject;
837 }
838 }
839
840 /* While there is more data in the status packet, keep processing
841 * status items. First make sure there is enough data for the
842 * segment descriptor's length field. */
843 while (packetlen >= 2) {
844 u_int segtype = data[0];
845 u_int segsize = data[1];
846
847 /* Now that we know how long it claims to be, make sure
848 * there is enough data for the next seg. */
849 if (packetlen < (segsize + 2)) {
850 log(LOG_WARNING, "nglmi: IE longer than packet\n");
851 break;
852 }
853 switch (segtype) {
854 case 0x01:
855 case 0x51:
856 /* According to MCI's HP analyser, we should just
857 * ignore if there is mor ethan one of these (?). */
858 if (resptype_seen) {
859 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
860 goto nextIE;
861 }
862 if (segsize != 1) {
863 log(LOG_WARNING, "nglmi: MSGTYPE wrong size\n");
864 goto reject;
865 }
866 /* The remote end tells us what kind of response
867 * this is. Only expect a type 0 or 1. if it was a
868 * full (type 0) check we just asked for a type
869 * full. */
870 switch (data[2]) {
871 case 1:/* partial */
872 if (sc->livs > sc->liv_per_full) {
873 log(LOG_WARNING,
874 "nglmi: LIV when FULL expected\n");
875 goto reject; /* need full */
876 }
877 resptype_seen = 1;
878 break;
879 case 0:/* full */
880 /* Full response is always acceptable */
881 resptype_seen = 2;
882 break;
883 default:
884 log(LOG_WARNING,
885 "nglmi: Unknown report type %d\n", data[2]);
886 goto reject;
887 }
888 break;
889 case 0x03:
890 case 0x53:
891 /* The remote tells us what it thinks the sequence
892 * numbers are. I would have thought that there
893 * needs to be one and only one of these, but MCI
894 * want us to just ignore extras. (?) */
895 if (resptype_seen == 0) {
896 log(LOG_WARNING, "nglmi: no TYPE before SEQ\n");
897 goto reject;
898 }
899 if (seq_seen != 0) /* already seen seq numbers */
900 goto nextIE;
901 if (segsize != 2) {
902 log(LOG_WARNING, "nglmi: bad SEQ sts size\n");
903 goto reject;
904 }
905 if (sc->local_seq != data[3]) {
906 log(LOG_WARNING, "nglmi: unexpected SEQ\n");
907 goto reject;
908 }
909 seq_seen = 1;
910 break;
911 case 0x07:
912 case 0x57:
913 /* The remote tells us about a DLCI that it knows
914 * about. There may be many of these in a single
915 * status response */
916 if (seq_seen != 1) { /* already seen seq numbers? */
917 log(LOG_WARNING,
918 "nglmi: No sequence before DLCI\n");
919 goto reject;
920 }
921 if (resptype_seen != 2) { /* must be full */
922 log(LOG_WARNING,
923 "nglmi: No resp type before DLCI\n");
924 goto reject;
925 }
926 if (GROUP4(sc)) {
927 if (segsize != 6) {
928 log(LOG_WARNING,
929 "nglmi: wrong IE segsize\n");
930 goto reject;
931 }
932 dlci = ((u_short) data[2] & 0xff) << 8;
933 dlci |= (data[3] & 0xff);
934 } else {
935 if (segsize != 3) {
936 log(LOG_WARNING,
937 "nglmi: DLCI headersize of %d"
938 " not supported\n", segsize - 1);
939 goto reject;
940 }
941 dlci = ((u_short) data[2] & 0x3f) << 4;
942 dlci |= ((data[3] & 0x78) >> 3);
943 }
944 /* async can only have one of these */
945 #if 0 /* async not yet accepted */
946 if (async && highest_dlci) {
947 log(LOG_WARNING,
948 "nglmi: Async with > 1 DLCI\n");
949 goto reject;
950 }
951 #endif
952 /* Annex D says these will always be Ascending, but
953 * the HP test for G4 says we should accept
954 * duplicates, so for now allow that. ( <= vs. < ) */
955 #if 0
956 /* MCI tests want us to accept out of order for AnxD */
957 if ((!GROUP4(sc)) && (dlci < highest_dlci)) {
958 /* duplicate or mis-ordered dlci */
959 /* (spec says they will increase in number) */
960 log(LOG_WARNING, "nglmi: DLCI out of order\n");
961 goto reject;
962 }
963 #endif
964 if (dlci > 1023) {
965 log(LOG_WARNING, "nglmi: DLCI out of range\n");
966 goto reject;
967 }
968 highest_dlci = dlci;
969 break;
970 default:
971 log(LOG_WARNING,
972 "nglmi: unknown LMI segment type %d\n", segtype);
973 }
974 nextIE:
975 STEPBY(segsize + 2);
976 }
977 if (packetlen != 0) { /* partial junk at end? */
978 log(LOG_WARNING,
979 "nglmi: %d bytes extra at end of packet\n", packetlen);
980 goto print;
981 }
982 if (resptype_seen == 0) {
983 log(LOG_WARNING, "nglmi: No response type seen\n");
984 goto reject; /* had no response type */
985 }
986 if (seq_seen == 0) {
987 log(LOG_WARNING, "nglmi: No sequence numbers seen\n");
988 goto reject; /* had no sequence numbers */
989 }
990 return (1);
991
992 print:
993 {
994 int i, j, k, pos;
995 char buf[100];
996 int loc;
997 const u_char *bp = mtod(m, const u_char *);
998
999 k = i = 0;
1000 loc = (m->m_hdr.mh_len - packetlen);
1001 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
1002 while (k < m->m_hdr.mh_len) {
1003 pos = 0;
1004 j = 0;
1005 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1006 pos += sprintf(buf + pos, "%c%02x",
1007 ((loc == k) ? '>' : ' '),
1008 bp[k]);
1009 k++;
1010 }
1011 if (i == 0)
1012 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1013 else
1014 log(LOG_WARNING, "%04d :%s\n", k, buf);
1015 i++;
1016 }
1017 }
1018 return (1);
1019 reject:
1020 {
1021 int i, j, k, pos;
1022 char buf[100];
1023 int loc;
1024 const u_char *bp = mtod(m, const u_char *);
1025
1026 k = i = 0;
1027 loc = (m->m_hdr.mh_len - packetlen);
1028 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
1029 while (k < m->m_hdr.mh_len) {
1030 pos = 0;
1031 j = 0;
1032 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1033 pos += sprintf(buf + pos, "%c%02x",
1034 ((loc == k) ? '>' : ' '),
1035 bp[k]);
1036 k++;
1037 }
1038 if (i == 0)
1039 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1040 else
1041 log(LOG_WARNING, "%04d :%s\n", k, buf);
1042 i++;
1043 }
1044 }
1045 NG_FREE_M(m);
1046 return (0);
1047 }
1048
1049 /*
1050 * Do local shutdown processing..
1051 * Cut any remaining links and free our local resources.
1052 */
1053 static int
1054 nglmi_shutdown(node_p node)
1055 {
1056 const sc_p sc = NG_NODE_PRIVATE(node);
1057
1058 NG_NODE_SET_PRIVATE(node, NULL);
1059 NG_NODE_UNREF(sc->node);
1060 FREE(sc, M_NETGRAPH);
1061 return (0);
1062 }
1063
1064 /*
1065 * Hook disconnection
1066 * For this type, removal of any link except "debug" destroys the node.
1067 */
1068 static int
1069 nglmi_disconnect(hook_p hook)
1070 {
1071 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1072
1073 /* OK to remove debug hook(s) */
1074 if (NG_HOOK_PRIVATE(hook) == NULL)
1075 return (0);
1076
1077 /* Stop timer if it's currently active */
1078 if (sc->flags & SCF_CONNECTED)
1079 untimeout(LMI_ticker, sc, sc->handle);
1080
1081 /* Self-destruct */
1082 if (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
1083 ng_rmnode_self(NG_HOOK_NODE(hook));
1084 return (0);
1085 }
1086
Cache object: 31cabdcec1f1626096ce7002c28855e0
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