FreeBSD/Linux Kernel Cross Reference
sys/netgraph/ng_lmi.c
1 /*
2 * ng_lmi.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Author: Julian Elischer <julian@freebsd.org>
39 *
40 * $FreeBSD: src/sys/netgraph/ng_lmi.c,v 1.19.2.2 2005/01/31 23:26:29 imp Exp $
41 * $Whistle: ng_lmi.c,v 1.38 1999/11/01 09:24:52 julian Exp $
42 */
43
44 /*
45 * This node performs the frame relay LMI protocol. It knows how
46 * to do ITU Annex A, ANSI Annex D, and "Group-of-Four" variants
47 * of the protocol.
48 *
49 * A specific protocol can be forced by connecting the corresponding
50 * hook to DLCI 0 or 1023 (as appropriate) of a frame relay link.
51 *
52 * Alternately, this node can do auto-detection of the LMI protocol
53 * by connecting hook "auto0" to DLCI 0 and "auto1023" to DLCI 1023.
54 */
55
56 #include <sys/param.h>
57 #include <sys/systm.h>
58 #include <sys/errno.h>
59 #include <sys/kernel.h>
60 #include <sys/malloc.h>
61 #include <sys/mbuf.h>
62 #include <sys/syslog.h>
63 #include <netgraph/ng_message.h>
64 #include <netgraph/netgraph.h>
65 #include <netgraph/ng_lmi.h>
66
67 /*
68 * Human readable names for LMI
69 */
70 #define NAME_ANNEXA NG_LMI_HOOK_ANNEXA
71 #define NAME_ANNEXD NG_LMI_HOOK_ANNEXD
72 #define NAME_GROUP4 NG_LMI_HOOK_GROUPOF4
73 #define NAME_NONE "None"
74
75 #define MAX_DLCIS 128
76 #define MAXDLCI 1023
77
78 /*
79 * DLCI states
80 */
81 #define DLCI_NULL 0
82 #define DLCI_UP 1
83 #define DLCI_DOWN 2
84
85 /*
86 * Any received LMI frame should be at least this long
87 */
88 #define LMI_MIN_LENGTH 8 /* XXX verify */
89
90 /*
91 * Netgraph node methods and type descriptor
92 */
93 static ng_constructor_t nglmi_constructor;
94 static ng_rcvmsg_t nglmi_rcvmsg;
95 static ng_shutdown_t nglmi_shutdown;
96 static ng_newhook_t nglmi_newhook;
97 static ng_rcvdata_t nglmi_rcvdata;
98 static ng_disconnect_t nglmi_disconnect;
99 static int nglmi_checkdata(hook_p hook, struct mbuf *m);
100
101 static struct ng_type typestruct = {
102 .version = NG_ABI_VERSION,
103 .name = NG_LMI_NODE_TYPE,
104 .constructor = nglmi_constructor,
105 .rcvmsg = nglmi_rcvmsg,
106 .shutdown = nglmi_shutdown,
107 .newhook = nglmi_newhook,
108 .rcvdata = nglmi_rcvdata,
109 .disconnect = nglmi_disconnect,
110 };
111 NETGRAPH_INIT(lmi, &typestruct);
112
113 /*
114 * Info and status per node
115 */
116 struct nglmi_softc {
117 node_p node; /* netgraph node */
118 int flags; /* state */
119 int poll_count; /* the count of times for autolmi */
120 int poll_state; /* state of auto detect machine */
121 u_char remote_seq; /* sequence number the remote sent */
122 u_char local_seq; /* last sequence number we sent */
123 u_char protoID; /* 9 for group of 4, 8 otherwise */
124 u_long seq_retries; /* sent this how many time so far */
125 struct callout_handle handle; /* see timeout(9) */
126 int liv_per_full;
127 int liv_rate;
128 int livs;
129 int need_full;
130 hook_p lmi_channel; /* whatever we ended up using */
131 hook_p lmi_annexA;
132 hook_p lmi_annexD;
133 hook_p lmi_group4;
134 hook_p lmi_channel0; /* auto-detect on DLCI 0 */
135 hook_p lmi_channel1023;/* auto-detect on DLCI 1023 */
136 char *protoname; /* cache protocol name */
137 u_char dlci_state[MAXDLCI + 1];
138 int invalidx; /* next dlci's to invalidate */
139 };
140 typedef struct nglmi_softc *sc_p;
141
142 /*
143 * Other internal functions
144 */
145 static void LMI_ticker(void *arg);
146 static void nglmi_startup_fixed(sc_p sc, hook_p hook);
147 static void nglmi_startup_auto(sc_p sc);
148 static void nglmi_startup(sc_p sc);
149 static void nglmi_inquire(sc_p sc, int full);
150 static void ngauto_state_machine(sc_p sc);
151
152 /*
153 * Values for 'flags' field
154 * NB: the SCF_CONNECTED flag is set if and only if the timer is running.
155 */
156 #define SCF_CONNECTED 0x01 /* connected to something */
157 #define SCF_AUTO 0x02 /* we are auto-detecting */
158 #define SCF_FIXED 0x04 /* we are fixed from the start */
159
160 #define SCF_LMITYPE 0x18 /* mask for determining Annex mode */
161 #define SCF_NOLMI 0x00 /* no LMI type selected yet */
162 #define SCF_ANNEX_A 0x08 /* running annex A mode */
163 #define SCF_ANNEX_D 0x10 /* running annex D mode */
164 #define SCF_GROUP4 0x18 /* running group of 4 */
165
166 #define SETLMITYPE(sc, annex) \
167 do { \
168 (sc)->flags &= ~SCF_LMITYPE; \
169 (sc)->flags |= (annex); \
170 } while (0)
171
172 #define NOPROTO(sc) (((sc)->flags & SCF_LMITYPE) == SCF_NOLMI)
173 #define ANNEXA(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_A)
174 #define ANNEXD(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_D)
175 #define GROUP4(sc) (((sc)->flags & SCF_LMITYPE) == SCF_GROUP4)
176
177 #define LMIPOLLSIZE 3
178 #define LMI_PATIENCE 8 /* declare all DLCI DOWN after N LMI failures */
179
180 /*
181 * Node constructor
182 */
183 static int
184 nglmi_constructor(node_p node)
185 {
186 sc_p sc;
187
188 MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
189 if (sc == NULL)
190 return (ENOMEM);
191 callout_handle_init(&sc->handle);
192 NG_NODE_SET_PRIVATE(node, sc);
193 sc->protoname = NAME_NONE;
194 sc->node = node;
195 sc->liv_per_full = NG_LMI_SEQ_PER_FULL; /* make this dynamic */
196 sc->liv_rate = NG_LMI_KEEPALIVE_RATE;
197 return (0);
198 }
199
200 /*
201 * The LMI channel has a private pointer which is the same as the
202 * node private pointer. The debug channel has a NULL private pointer.
203 */
204 static int
205 nglmi_newhook(node_p node, hook_p hook, const char *name)
206 {
207 sc_p sc = NG_NODE_PRIVATE(node);
208
209 if (strcmp(name, NG_LMI_HOOK_DEBUG) == 0) {
210 NG_HOOK_SET_PRIVATE(hook, NULL);
211 return (0);
212 }
213 if (sc->flags & SCF_CONNECTED) {
214 /* already connected, return an error */
215 return (EINVAL);
216 }
217 if (strcmp(name, NG_LMI_HOOK_ANNEXA) == 0) {
218 sc->lmi_annexA = hook;
219 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
220 sc->protoID = 8;
221 SETLMITYPE(sc, SCF_ANNEX_A);
222 sc->protoname = NAME_ANNEXA;
223 nglmi_startup_fixed(sc, hook);
224 } else if (strcmp(name, NG_LMI_HOOK_ANNEXD) == 0) {
225 sc->lmi_annexD = hook;
226 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
227 sc->protoID = 8;
228 SETLMITYPE(sc, SCF_ANNEX_D);
229 sc->protoname = NAME_ANNEXD;
230 nglmi_startup_fixed(sc, hook);
231 } else if (strcmp(name, NG_LMI_HOOK_GROUPOF4) == 0) {
232 sc->lmi_group4 = hook;
233 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
234 sc->protoID = 9;
235 SETLMITYPE(sc, SCF_GROUP4);
236 sc->protoname = NAME_GROUP4;
237 nglmi_startup_fixed(sc, hook);
238 } else if (strcmp(name, NG_LMI_HOOK_AUTO0) == 0) {
239 /* Note this, and if B is already installed, we're complete */
240 sc->lmi_channel0 = hook;
241 sc->protoname = NAME_NONE;
242 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
243 if (sc->lmi_channel1023)
244 nglmi_startup_auto(sc);
245 } else if (strcmp(name, NG_LMI_HOOK_AUTO1023) == 0) {
246 /* Note this, and if A is already installed, we're complete */
247 sc->lmi_channel1023 = hook;
248 sc->protoname = NAME_NONE;
249 NG_HOOK_SET_PRIVATE(hook, NG_NODE_PRIVATE(node));
250 if (sc->lmi_channel0)
251 nglmi_startup_auto(sc);
252 } else
253 return (EINVAL); /* unknown hook */
254 return (0);
255 }
256
257 /*
258 * We have just attached to a live (we hope) node.
259 * Fire out a LMI inquiry, and then start up the timers.
260 */
261 static void
262 LMI_ticker(void *arg)
263 {
264 sc_p sc = arg;
265 int s = splnet();
266
267 if (sc->flags & SCF_AUTO) {
268 ngauto_state_machine(sc);
269 sc->handle = timeout(LMI_ticker, sc, NG_LMI_POLL_RATE * hz);
270 } else {
271 if (sc->livs++ >= sc->liv_per_full) {
272 nglmi_inquire(sc, 1);
273 /* sc->livs = 0; *//* do this when we get the answer! */
274 } else {
275 nglmi_inquire(sc, 0);
276 }
277 sc->handle = timeout(LMI_ticker, sc, sc->liv_rate * hz);
278 }
279 splx(s);
280 }
281
282 static void
283 nglmi_startup_fixed(sc_p sc, hook_p hook)
284 {
285 sc->flags |= (SCF_FIXED | SCF_CONNECTED);
286 sc->lmi_channel = hook;
287 nglmi_startup(sc);
288 }
289
290 static void
291 nglmi_startup_auto(sc_p sc)
292 {
293 sc->flags |= (SCF_AUTO | SCF_CONNECTED);
294 sc->poll_state = 0; /* reset state machine */
295 sc->poll_count = 0;
296 nglmi_startup(sc);
297 }
298
299 static void
300 nglmi_startup(sc_p sc)
301 {
302 sc->remote_seq = 0;
303 sc->local_seq = 1;
304 sc->seq_retries = 0;
305 sc->livs = sc->liv_per_full - 1;
306 /* start off the ticker in 1 sec */
307 sc->handle = timeout(LMI_ticker, sc, hz);
308 }
309
310 static void
311 nglmi_inquire(sc_p sc, int full)
312 {
313 struct mbuf *m;
314 struct ng_tag_prio *ptag;
315 char *cptr, *start;
316 int error;
317
318 if (sc->lmi_channel == NULL)
319 return;
320 MGETHDR(m, M_DONTWAIT, MT_DATA);
321 if (m == NULL) {
322 log(LOG_ERR, "nglmi: unable to start up LMI processing\n");
323 return;
324 }
325 m->m_pkthdr.rcvif = NULL;
326
327 /* Attach a tag to packet, marking it of link level state priority, so
328 * that device driver would put it in the beginning of queue */
329
330 ptag = (struct ng_tag_prio *)m_tag_alloc(NGM_GENERIC_COOKIE, NG_TAG_PRIO,
331 (sizeof(struct ng_tag_prio) - sizeof(struct m_tag)), M_NOWAIT);
332 if (ptag != NULL) { /* if it failed, well, it was optional anyhow */
333 ptag->priority = NG_PRIO_LINKSTATE;
334 ptag->discardability = -1;
335 m_tag_prepend(m, &ptag->tag);
336 }
337
338 m->m_data += 4; /* leave some room for a header */
339 cptr = start = mtod(m, char *);
340 /* add in the header for an LMI inquiry. */
341 *cptr++ = 0x03; /* UI frame */
342 if (GROUP4(sc))
343 *cptr++ = 0x09; /* proto discriminator */
344 else
345 *cptr++ = 0x08; /* proto discriminator */
346 *cptr++ = 0x00; /* call reference */
347 *cptr++ = 0x75; /* inquiry */
348
349 /* If we are Annex-D, add locking shift to codeset 5. */
350 if (ANNEXD(sc))
351 *cptr++ = 0x95; /* locking shift */
352 /* Add a request type */
353 if (ANNEXA(sc))
354 *cptr++ = 0x51; /* report type */
355 else
356 *cptr++ = 0x01; /* report type */
357 *cptr++ = 0x01; /* size = 1 */
358 if (full)
359 *cptr++ = 0x00; /* full */
360 else
361 *cptr++ = 0x01; /* partial */
362
363 /* Add a link verification IE */
364 if (ANNEXA(sc))
365 *cptr++ = 0x53; /* verification IE */
366 else
367 *cptr++ = 0x03; /* verification IE */
368 *cptr++ = 0x02; /* 2 extra bytes */
369 *cptr++ = sc->local_seq;
370 *cptr++ = sc->remote_seq;
371 sc->seq_retries++;
372
373 /* Send it */
374 m->m_len = m->m_pkthdr.len = cptr - start;
375 NG_SEND_DATA_ONLY(error, sc->lmi_channel, m);
376
377 /* If we've been sending requests for long enough, and there has
378 * been no response, then mark as DOWN, any DLCIs that are UP. */
379 if (sc->seq_retries == LMI_PATIENCE) {
380 int count;
381
382 for (count = 0; count < MAXDLCI; count++)
383 if (sc->dlci_state[count] == DLCI_UP)
384 sc->dlci_state[count] = DLCI_DOWN;
385 }
386 }
387
388 /*
389 * State machine for LMI auto-detect. The transitions are ordered
390 * to try the more likely possibilities first.
391 */
392 static void
393 ngauto_state_machine(sc_p sc)
394 {
395 if ((sc->poll_count <= 0) || (sc->poll_count > LMIPOLLSIZE)) {
396 /* time to change states in the auto probe machine */
397 /* capture wild values of poll_count while we are at it */
398 sc->poll_count = LMIPOLLSIZE;
399 sc->poll_state++;
400 }
401 switch (sc->poll_state) {
402 case 7:
403 log(LOG_WARNING, "nglmi: no response from exchange\n");
404 default: /* capture bad states */
405 sc->poll_state = 1;
406 case 1:
407 sc->lmi_channel = sc->lmi_channel0;
408 SETLMITYPE(sc, SCF_ANNEX_D);
409 break;
410 case 2:
411 sc->lmi_channel = sc->lmi_channel1023;
412 SETLMITYPE(sc, SCF_ANNEX_D);
413 break;
414 case 3:
415 sc->lmi_channel = sc->lmi_channel0;
416 SETLMITYPE(sc, SCF_ANNEX_A);
417 break;
418 case 4:
419 sc->lmi_channel = sc->lmi_channel1023;
420 SETLMITYPE(sc, SCF_GROUP4);
421 break;
422 case 5:
423 sc->lmi_channel = sc->lmi_channel1023;
424 SETLMITYPE(sc, SCF_ANNEX_A);
425 break;
426 case 6:
427 sc->lmi_channel = sc->lmi_channel0;
428 SETLMITYPE(sc, SCF_GROUP4);
429 break;
430 }
431
432 /* send an inquirey encoded appropriatly */
433 nglmi_inquire(sc, 0);
434 sc->poll_count--;
435 }
436
437 /*
438 * Receive a netgraph control message.
439 */
440 static int
441 nglmi_rcvmsg(node_p node, item_p item, hook_p lasthook)
442 {
443 sc_p sc = NG_NODE_PRIVATE(node);
444 struct ng_mesg *resp = NULL;
445 int error = 0;
446 struct ng_mesg *msg;
447
448 NGI_GET_MSG(item, msg);
449 switch (msg->header.typecookie) {
450 case NGM_GENERIC_COOKIE:
451 switch (msg->header.cmd) {
452 case NGM_TEXT_STATUS:
453 {
454 char *arg;
455 int pos, count;
456
457 NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
458 if (resp == NULL) {
459 error = ENOMEM;
460 break;
461 }
462 arg = resp->data;
463 pos = sprintf(arg, "protocol %s ", sc->protoname);
464 if (sc->flags & SCF_FIXED)
465 pos += sprintf(arg + pos, "fixed\n");
466 else if (sc->flags & SCF_AUTO)
467 pos += sprintf(arg + pos, "auto-detecting\n");
468 else
469 pos += sprintf(arg + pos, "auto on dlci %d\n",
470 (sc->lmi_channel == sc->lmi_channel0) ?
471 0 : 1023);
472 pos += sprintf(arg + pos,
473 "keepalive period: %d seconds\n", sc->liv_rate);
474 pos += sprintf(arg + pos,
475 "unacknowledged keepalives: %ld\n",
476 sc->seq_retries);
477 for (count = 0;
478 ((count <= MAXDLCI)
479 && (pos < (NG_TEXTRESPONSE - 20)));
480 count++) {
481 if (sc->dlci_state[count]) {
482 pos += sprintf(arg + pos,
483 "dlci %d %s\n", count,
484 (sc->dlci_state[count]
485 == DLCI_UP) ? "up" : "down");
486 }
487 }
488 resp->header.arglen = pos + 1;
489 break;
490 }
491 default:
492 error = EINVAL;
493 break;
494 }
495 break;
496 case NGM_LMI_COOKIE:
497 switch (msg->header.cmd) {
498 case NGM_LMI_GET_STATUS:
499 {
500 struct nglmistat *stat;
501 int k;
502
503 NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
504 if (!resp) {
505 error = ENOMEM;
506 break;
507 }
508 stat = (struct nglmistat *) resp->data;
509 strncpy(stat->proto,
510 sc->protoname, sizeof(stat->proto) - 1);
511 strncpy(stat->hook,
512 sc->protoname, sizeof(stat->hook) - 1);
513 stat->autod = !!(sc->flags & SCF_AUTO);
514 stat->fixed = !!(sc->flags & SCF_FIXED);
515 for (k = 0; k <= MAXDLCI; k++) {
516 switch (sc->dlci_state[k]) {
517 case DLCI_UP:
518 stat->up[k / 8] |= (1 << (k % 8));
519 /* fall through */
520 case DLCI_DOWN:
521 stat->seen[k / 8] |= (1 << (k % 8));
522 break;
523 }
524 }
525 break;
526 }
527 default:
528 error = EINVAL;
529 break;
530 }
531 break;
532 default:
533 error = EINVAL;
534 break;
535 }
536
537 NG_RESPOND_MSG(error, node, item, resp);
538 NG_FREE_MSG(msg);
539 return (error);
540 }
541
542 #define STEPBY(stepsize) \
543 do { \
544 packetlen -= (stepsize); \
545 data += (stepsize); \
546 } while (0)
547
548 /*
549 * receive data, and use it to update our status.
550 * Anything coming in on the debug port is discarded.
551 */
552 static int
553 nglmi_rcvdata(hook_p hook, item_p item)
554 {
555 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
556 const u_char *data;
557 unsigned short dlci;
558 u_short packetlen;
559 int resptype_seen = 0;
560 int seq_seen = 0;
561 struct mbuf *m;
562
563 NGI_GET_M(item, m);
564 NG_FREE_ITEM(item);
565 if (NG_HOOK_PRIVATE(hook) == NULL) {
566 goto drop;
567 }
568 packetlen = m->m_hdr.mh_len;
569
570 /* XXX what if it's more than 1 mbuf? */
571 if ((packetlen > MHLEN) && !(m->m_flags & M_EXT)) {
572 log(LOG_WARNING, "nglmi: packetlen (%d) too big\n", packetlen);
573 goto drop;
574 }
575 if (m->m_len < packetlen && (m = m_pullup(m, packetlen)) == NULL) {
576 log(LOG_WARNING,
577 "nglmi: m_pullup failed for %d bytes\n", packetlen);
578 return (0);
579 }
580 if (nglmi_checkdata(hook, m) == 0)
581 return (0);
582
583 /* pass the first 4 bytes (already checked in the nglmi_checkdata()) */
584 data = mtod(m, const u_char *);
585 STEPBY(4);
586
587 /* Now check if there is a 'locking shift'. This is only seen in
588 * Annex D frames. don't bother checking, we already did that. Don't
589 * increment immediatly as it might not be there. */
590 if (ANNEXD(sc))
591 STEPBY(1);
592
593 /* If we get this far we should consider that it is a legitimate
594 * frame and we know what it is. */
595 if (sc->flags & SCF_AUTO) {
596 /* note the hook that this valid channel came from and drop
597 * out of auto probe mode. */
598 if (ANNEXA(sc))
599 sc->protoname = NAME_ANNEXA;
600 else if (ANNEXD(sc))
601 sc->protoname = NAME_ANNEXD;
602 else if (GROUP4(sc))
603 sc->protoname = NAME_GROUP4;
604 else {
605 log(LOG_ERR, "nglmi: No known type\n");
606 goto drop;
607 }
608 sc->lmi_channel = hook;
609 sc->flags &= ~SCF_AUTO;
610 log(LOG_INFO, "nglmi: auto-detected %s LMI on DLCI %d\n",
611 sc->protoname, hook == sc->lmi_channel0 ? 0 : 1023);
612 }
613
614 /* While there is more data in the status packet, keep processing
615 * status items. First make sure there is enough data for the
616 * segment descriptor's length field. */
617 while (packetlen >= 2) {
618 u_int segtype = data[0];
619 u_int segsize = data[1];
620
621 /* Now that we know how long it claims to be, make sure
622 * there is enough data for the next seg. */
623 if (packetlen < segsize + 2)
624 break;
625 switch (segtype) {
626 case 0x01:
627 case 0x51:
628 if (resptype_seen) {
629 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
630 goto nextIE;
631 }
632 resptype_seen++;
633 /* The remote end tells us what kind of response
634 * this is. Only expect a type 0 or 1. if we are a
635 * full status, invalidate a few DLCIs just to see
636 * that they are still ok. */
637 if (segsize != 1)
638 goto nextIE;
639 switch (data[2]) {
640 case 1:
641 /* partial status, do no extra processing */
642 break;
643 case 0:
644 {
645 int count = 0;
646 int idx = sc->invalidx;
647
648 for (count = 0; count < 10; count++) {
649 if (idx > MAXDLCI)
650 idx = 0;
651 if (sc->dlci_state[idx] == DLCI_UP)
652 sc->dlci_state[idx] = DLCI_DOWN;
653 idx++;
654 }
655 sc->invalidx = idx;
656 /* we got and we wanted one. relax
657 * now.. but don't reset to 0 if it
658 * was unrequested. */
659 if (sc->livs > sc->liv_per_full)
660 sc->livs = 0;
661 break;
662 }
663 }
664 break;
665 case 0x03:
666 case 0x53:
667 /* The remote tells us what it thinks the sequence
668 * numbers are. If it's not size 2, it must be a
669 * duplicate to have gotten this far, skip it. */
670 if (seq_seen != 0) /* already seen seq numbers */
671 goto nextIE;
672 if (segsize != 2)
673 goto nextIE;
674 sc->remote_seq = data[2];
675 if (sc->local_seq == data[3]) {
676 sc->local_seq++;
677 sc->seq_retries = 0;
678 /* Note that all 3 Frame protocols seem to
679 * not like 0 as a sequence number. */
680 if (sc->local_seq == 0)
681 sc->local_seq = 1;
682 }
683 break;
684 case 0x07:
685 case 0x57:
686 /* The remote tells us about a DLCI that it knows
687 * about. There may be many of these in a single
688 * status response */
689 switch (segsize) {
690 case 6:/* only on 'group of 4' */
691 dlci = ((u_short) data[2] & 0xff) << 8;
692 dlci |= (data[3] & 0xff);
693 if ((dlci < 1024) && (dlci > 0)) {
694 /* XXX */
695 }
696 break;
697 case 3:
698 dlci = ((u_short) data[2] & 0x3f) << 4;
699 dlci |= ((data[3] & 0x78) >> 3);
700 if ((dlci < 1024) && (dlci > 0)) {
701 /* set up the bottom half of the
702 * support for that dlci if it's not
703 * already been done */
704 /* store this information somewhere */
705 }
706 break;
707 default:
708 goto nextIE;
709 }
710 if (sc->dlci_state[dlci] != DLCI_UP) {
711 /* bring new DLCI to life */
712 /* may do more here some day */
713 if (sc->dlci_state[dlci] != DLCI_DOWN)
714 log(LOG_INFO,
715 "nglmi: DLCI %d became active\n",
716 dlci);
717 sc->dlci_state[dlci] = DLCI_UP;
718 }
719 break;
720 }
721 nextIE:
722 STEPBY(segsize + 2);
723 }
724 NG_FREE_M(m);
725 return (0);
726
727 drop:
728 NG_FREE_M(m);
729 return (EINVAL);
730 }
731
732 /*
733 * Check that a packet is entirely kosha.
734 * return 1 of ok, and 0 if not.
735 * All data is discarded if a 0 is returned.
736 */
737 static int
738 nglmi_checkdata(hook_p hook, struct mbuf *m)
739 {
740 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
741 const u_char *data;
742 u_short packetlen;
743 unsigned short dlci;
744 u_char type;
745 u_char nextbyte;
746 int seq_seen = 0;
747 int resptype_seen = 0; /* 0 , 1 (partial) or 2 (full) */
748 int highest_dlci = 0;
749
750 packetlen = m->m_hdr.mh_len;
751 data = mtod(m, const u_char *);
752 if (*data != 0x03) {
753 log(LOG_WARNING, "nglmi: unexpected value in LMI(%d)\n", 1);
754 goto reject;
755 }
756 STEPBY(1);
757
758 /* look at the protocol ID */
759 nextbyte = *data;
760 if (sc->flags & SCF_AUTO) {
761 SETLMITYPE(sc, SCF_NOLMI); /* start with a clean slate */
762 switch (nextbyte) {
763 case 0x8:
764 sc->protoID = 8;
765 break;
766 case 0x9:
767 SETLMITYPE(sc, SCF_GROUP4);
768 sc->protoID = 9;
769 break;
770 default:
771 log(LOG_WARNING, "nglmi: bad Protocol ID(%d)\n",
772 (int) nextbyte);
773 goto reject;
774 }
775 } else {
776 if (nextbyte != sc->protoID) {
777 log(LOG_WARNING, "nglmi: unexpected Protocol ID(%d)\n",
778 (int) nextbyte);
779 goto reject;
780 }
781 }
782 STEPBY(1);
783
784 /* check call reference (always null in non ISDN frame relay) */
785 if (*data != 0x00) {
786 log(LOG_WARNING, "nglmi: unexpected Call Reference (0x%x)\n",
787 data[-1]);
788 goto reject;
789 }
790 STEPBY(1);
791
792 /* check message type */
793 switch ((type = *data)) {
794 case 0x75: /* Status enquiry */
795 log(LOG_WARNING, "nglmi: unexpected message type(0x%x)\n",
796 data[-1]);
797 goto reject;
798 case 0x7D: /* Status message */
799 break;
800 default:
801 log(LOG_WARNING,
802 "nglmi: unexpected msg type(0x%x) \n", (int) type);
803 goto reject;
804 }
805 STEPBY(1);
806
807 /* Now check if there is a 'locking shift'. This is only seen in
808 * Annex D frames. Don't increment immediately as it might not be
809 * there. */
810 nextbyte = *data;
811 if (sc->flags & SCF_AUTO) {
812 if (!(GROUP4(sc))) {
813 if (nextbyte == 0x95) {
814 SETLMITYPE(sc, SCF_ANNEX_D);
815 STEPBY(1);
816 } else
817 SETLMITYPE(sc, SCF_ANNEX_A);
818 } else if (nextbyte == 0x95) {
819 log(LOG_WARNING, "nglmi: locking shift seen in G4\n");
820 goto reject;
821 }
822 } else {
823 if (ANNEXD(sc)) {
824 if (*data == 0x95)
825 STEPBY(1);
826 else {
827 log(LOG_WARNING,
828 "nglmi: locking shift missing\n");
829 goto reject;
830 }
831 } else if (*data == 0x95) {
832 log(LOG_WARNING, "nglmi: locking shift seen\n");
833 goto reject;
834 }
835 }
836
837 /* While there is more data in the status packet, keep processing
838 * status items. First make sure there is enough data for the
839 * segment descriptor's length field. */
840 while (packetlen >= 2) {
841 u_int segtype = data[0];
842 u_int segsize = data[1];
843
844 /* Now that we know how long it claims to be, make sure
845 * there is enough data for the next seg. */
846 if (packetlen < (segsize + 2)) {
847 log(LOG_WARNING, "nglmi: IE longer than packet\n");
848 break;
849 }
850 switch (segtype) {
851 case 0x01:
852 case 0x51:
853 /* According to MCI's HP analyser, we should just
854 * ignore if there is mor ethan one of these (?). */
855 if (resptype_seen) {
856 log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
857 goto nextIE;
858 }
859 if (segsize != 1) {
860 log(LOG_WARNING, "nglmi: MSGTYPE wrong size\n");
861 goto reject;
862 }
863 /* The remote end tells us what kind of response
864 * this is. Only expect a type 0 or 1. if it was a
865 * full (type 0) check we just asked for a type
866 * full. */
867 switch (data[2]) {
868 case 1:/* partial */
869 if (sc->livs > sc->liv_per_full) {
870 log(LOG_WARNING,
871 "nglmi: LIV when FULL expected\n");
872 goto reject; /* need full */
873 }
874 resptype_seen = 1;
875 break;
876 case 0:/* full */
877 /* Full response is always acceptable */
878 resptype_seen = 2;
879 break;
880 default:
881 log(LOG_WARNING,
882 "nglmi: Unknown report type %d\n", data[2]);
883 goto reject;
884 }
885 break;
886 case 0x03:
887 case 0x53:
888 /* The remote tells us what it thinks the sequence
889 * numbers are. I would have thought that there
890 * needs to be one and only one of these, but MCI
891 * want us to just ignore extras. (?) */
892 if (resptype_seen == 0) {
893 log(LOG_WARNING, "nglmi: no TYPE before SEQ\n");
894 goto reject;
895 }
896 if (seq_seen != 0) /* already seen seq numbers */
897 goto nextIE;
898 if (segsize != 2) {
899 log(LOG_WARNING, "nglmi: bad SEQ sts size\n");
900 goto reject;
901 }
902 if (sc->local_seq != data[3]) {
903 log(LOG_WARNING, "nglmi: unexpected SEQ\n");
904 goto reject;
905 }
906 seq_seen = 1;
907 break;
908 case 0x07:
909 case 0x57:
910 /* The remote tells us about a DLCI that it knows
911 * about. There may be many of these in a single
912 * status response */
913 if (seq_seen != 1) { /* already seen seq numbers? */
914 log(LOG_WARNING,
915 "nglmi: No sequence before DLCI\n");
916 goto reject;
917 }
918 if (resptype_seen != 2) { /* must be full */
919 log(LOG_WARNING,
920 "nglmi: No resp type before DLCI\n");
921 goto reject;
922 }
923 if (GROUP4(sc)) {
924 if (segsize != 6) {
925 log(LOG_WARNING,
926 "nglmi: wrong IE segsize\n");
927 goto reject;
928 }
929 dlci = ((u_short) data[2] & 0xff) << 8;
930 dlci |= (data[3] & 0xff);
931 } else {
932 if (segsize != 3) {
933 log(LOG_WARNING,
934 "nglmi: DLCI headersize of %d"
935 " not supported\n", segsize - 1);
936 goto reject;
937 }
938 dlci = ((u_short) data[2] & 0x3f) << 4;
939 dlci |= ((data[3] & 0x78) >> 3);
940 }
941 /* async can only have one of these */
942 #if 0 /* async not yet accepted */
943 if (async && highest_dlci) {
944 log(LOG_WARNING,
945 "nglmi: Async with > 1 DLCI\n");
946 goto reject;
947 }
948 #endif
949 /* Annex D says these will always be Ascending, but
950 * the HP test for G4 says we should accept
951 * duplicates, so for now allow that. ( <= vs. < ) */
952 #if 0
953 /* MCI tests want us to accept out of order for AnxD */
954 if ((!GROUP4(sc)) && (dlci < highest_dlci)) {
955 /* duplicate or mis-ordered dlci */
956 /* (spec says they will increase in number) */
957 log(LOG_WARNING, "nglmi: DLCI out of order\n");
958 goto reject;
959 }
960 #endif
961 if (dlci > 1023) {
962 log(LOG_WARNING, "nglmi: DLCI out of range\n");
963 goto reject;
964 }
965 highest_dlci = dlci;
966 break;
967 default:
968 log(LOG_WARNING,
969 "nglmi: unknown LMI segment type %d\n", segtype);
970 }
971 nextIE:
972 STEPBY(segsize + 2);
973 }
974 if (packetlen != 0) { /* partial junk at end? */
975 log(LOG_WARNING,
976 "nglmi: %d bytes extra at end of packet\n", packetlen);
977 goto print;
978 }
979 if (resptype_seen == 0) {
980 log(LOG_WARNING, "nglmi: No response type seen\n");
981 goto reject; /* had no response type */
982 }
983 if (seq_seen == 0) {
984 log(LOG_WARNING, "nglmi: No sequence numbers seen\n");
985 goto reject; /* had no sequence numbers */
986 }
987 return (1);
988
989 print:
990 {
991 int i, j, k, pos;
992 char buf[100];
993 int loc;
994 const u_char *bp = mtod(m, const u_char *);
995
996 k = i = 0;
997 loc = (m->m_hdr.mh_len - packetlen);
998 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
999 while (k < m->m_hdr.mh_len) {
1000 pos = 0;
1001 j = 0;
1002 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1003 pos += sprintf(buf + pos, "%c%02x",
1004 ((loc == k) ? '>' : ' '),
1005 bp[k]);
1006 k++;
1007 }
1008 if (i == 0)
1009 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1010 else
1011 log(LOG_WARNING, "%04d :%s\n", k, buf);
1012 i++;
1013 }
1014 }
1015 return (1);
1016 reject:
1017 {
1018 int i, j, k, pos;
1019 char buf[100];
1020 int loc;
1021 const u_char *bp = mtod(m, const u_char *);
1022
1023 k = i = 0;
1024 loc = (m->m_hdr.mh_len - packetlen);
1025 log(LOG_WARNING, "nglmi: error at location %d\n", loc);
1026 while (k < m->m_hdr.mh_len) {
1027 pos = 0;
1028 j = 0;
1029 while ((j++ < 16) && k < m->m_hdr.mh_len) {
1030 pos += sprintf(buf + pos, "%c%02x",
1031 ((loc == k) ? '>' : ' '),
1032 bp[k]);
1033 k++;
1034 }
1035 if (i == 0)
1036 log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
1037 else
1038 log(LOG_WARNING, "%04d :%s\n", k, buf);
1039 i++;
1040 }
1041 }
1042 NG_FREE_M(m);
1043 return (0);
1044 }
1045
1046 /*
1047 * Do local shutdown processing..
1048 * Cut any remaining links and free our local resources.
1049 */
1050 static int
1051 nglmi_shutdown(node_p node)
1052 {
1053 const sc_p sc = NG_NODE_PRIVATE(node);
1054
1055 NG_NODE_SET_PRIVATE(node, NULL);
1056 NG_NODE_UNREF(sc->node);
1057 FREE(sc, M_NETGRAPH);
1058 return (0);
1059 }
1060
1061 /*
1062 * Hook disconnection
1063 * For this type, removal of any link except "debug" destroys the node.
1064 */
1065 static int
1066 nglmi_disconnect(hook_p hook)
1067 {
1068 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
1069
1070 /* OK to remove debug hook(s) */
1071 if (NG_HOOK_PRIVATE(hook) == NULL)
1072 return (0);
1073
1074 /* Stop timer if it's currently active */
1075 if (sc->flags & SCF_CONNECTED)
1076 untimeout(LMI_ticker, sc, sc->handle);
1077
1078 /* Self-destruct */
1079 if (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
1080 ng_rmnode_self(NG_HOOK_NODE(hook));
1081 return (0);
1082 }
1083
Cache object: 34d79ddada1344caecbceb928c218862
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