FreeBSD/Linux Kernel Cross Reference
sys/netgraph/ng_ppp.c
1
2 /*
3 * ng_ppp.c
4 *
5 * Copyright (c) 1996-2000 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: Archie Cobbs <archie@freebsd.org>
38 *
39 * $FreeBSD$
40 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $
41 */
42
43 /*
44 * PPP node type.
45 */
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/kernel.h>
50 #include <sys/time.h>
51 #include <sys/mbuf.h>
52 #include <sys/malloc.h>
53 #include <sys/errno.h>
54 #include <sys/syslog.h>
55 #include <sys/ctype.h>
56
57 #include <machine/limits.h>
58
59 #include <netgraph/ng_message.h>
60 #include <netgraph/netgraph.h>
61 #include <netgraph/ng_parse.h>
62 #include <netgraph/ng_ppp.h>
63 #include <netgraph/ng_vjc.h>
64
65 #define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
66 #define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
67
68 /* Some PPP protocol numbers we're interested in */
69 #define PROT_APPLETALK 0x0029
70 #define PROT_COMPD 0x00fd
71 #define PROT_CRYPTD 0x0053
72 #define PROT_IP 0x0021
73 #define PROT_IPV6 0x0057
74 #define PROT_IPX 0x002b
75 #define PROT_LCP 0xc021
76 #define PROT_MP 0x003d
77 #define PROT_VJCOMP 0x002d
78 #define PROT_VJUNCOMP 0x002f
79
80 /* Multilink PPP definitions */
81 #define MP_MIN_MRRU 1500 /* per RFC 1990 */
82 #define MP_INITIAL_SEQ 0 /* per RFC 1990 */
83 #define MP_MIN_LINK_MRU 32
84
85 #define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
86 #define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
87 #define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
88 #define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
89
90 #define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
91 #define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
92 #define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
93 #define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
94
95 #define MP_NOSEQ INT_MAX /* impossible sequence number */
96
97 #define MP_SEQ_MASK(priv) ((priv)->conf.recvShortSeq ? \
98 MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK)
99
100 /* Sign extension of MP sequence numbers */
101 #define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
102 ((s) | ~MP_SHORT_SEQ_MASK) : (s))
103 #define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
104 ((s) | ~MP_LONG_SEQ_MASK) : (s))
105
106 /* Comparision of MP sequence numbers */
107 #define MP_SHORT_SEQ_DIFF(x,y) (MP_SHORT_EXTEND(x) - MP_SHORT_EXTEND(y))
108 #define MP_LONG_SEQ_DIFF(x,y) (MP_LONG_EXTEND(x) - MP_LONG_EXTEND(y))
109
110 #define MP_SEQ_DIFF(priv,x,y) ((priv)->conf.recvShortSeq ? \
111 MP_SHORT_SEQ_DIFF((x), (y)) : \
112 MP_LONG_SEQ_DIFF((x), (y)))
113
114 #define MP_NEXT_SEQ(priv,seq) (((seq) + 1) & MP_SEQ_MASK(priv))
115 #define MP_PREV_SEQ(priv,seq) (((seq) - 1) & MP_SEQ_MASK(priv))
116
117 /* Don't fragment transmitted packets smaller than this */
118 #define MP_MIN_FRAG_LEN 6
119
120 /* Maximum fragment reasssembly queue length */
121 #define MP_MAX_QUEUE_LEN 128
122
123 /* Fragment queue scanner period */
124 #define MP_FRAGTIMER_INTERVAL (hz/2)
125
126 /* We store incoming fragments this way */
127 struct ng_ppp_frag {
128 int seq; /* fragment seq# */
129 u_char first; /* First in packet? */
130 u_char last; /* Last in packet? */
131 struct timeval timestamp; /* time of reception */
132 struct mbuf *data; /* Fragment data */
133 meta_p meta; /* Fragment meta */
134 CIRCLEQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
135 };
136
137 /* We use integer indicies to refer to the non-link hooks */
138 static const char *const ng_ppp_hook_names[] = {
139 NG_PPP_HOOK_ATALK,
140 #define HOOK_INDEX_ATALK 0
141 NG_PPP_HOOK_BYPASS,
142 #define HOOK_INDEX_BYPASS 1
143 NG_PPP_HOOK_COMPRESS,
144 #define HOOK_INDEX_COMPRESS 2
145 NG_PPP_HOOK_ENCRYPT,
146 #define HOOK_INDEX_ENCRYPT 3
147 NG_PPP_HOOK_DECOMPRESS,
148 #define HOOK_INDEX_DECOMPRESS 4
149 NG_PPP_HOOK_DECRYPT,
150 #define HOOK_INDEX_DECRYPT 5
151 NG_PPP_HOOK_INET,
152 #define HOOK_INDEX_INET 6
153 NG_PPP_HOOK_IPX,
154 #define HOOK_INDEX_IPX 7
155 NG_PPP_HOOK_VJC_COMP,
156 #define HOOK_INDEX_VJC_COMP 8
157 NG_PPP_HOOK_VJC_IP,
158 #define HOOK_INDEX_VJC_IP 9
159 NG_PPP_HOOK_VJC_UNCOMP,
160 #define HOOK_INDEX_VJC_UNCOMP 10
161 NG_PPP_HOOK_VJC_VJIP,
162 #define HOOK_INDEX_VJC_VJIP 11
163 NG_PPP_HOOK_IPV6,
164 #define HOOK_INDEX_IPV6 12
165 NULL
166 #define HOOK_INDEX_MAX 13
167 };
168
169 /* We store index numbers in the hook private pointer. The HOOK_INDEX()
170 for a hook is either the index (above) for normal hooks, or the ones
171 complement of the link number for link hooks. */
172 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
173
174 /* Per-link private information */
175 struct ng_ppp_link {
176 struct ng_ppp_link_conf conf; /* link configuration */
177 hook_p hook; /* connection to link data */
178 int seq; /* highest rec'd seq# - MSEQ */
179 struct timeval lastWrite; /* time of last write */
180 int bytesInQueue; /* bytes in the output queue */
181 struct ng_ppp_link_stat stats; /* Link stats */
182 };
183
184 /* Total per-node private information */
185 struct ng_ppp_private {
186 struct ng_ppp_bund_conf conf; /* bundle config */
187 struct ng_ppp_link_stat bundleStats; /* bundle stats */
188 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
189 int xseq; /* next out MP seq # */
190 int mseq; /* min links[i].seq */
191 u_char vjCompHooked; /* VJ comp hooked up? */
192 u_char allLinksEqual; /* all xmit the same? */
193 u_char timerActive; /* frag timer active? */
194 u_int numActiveLinks; /* how many links up */
195 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
196 u_int lastLink; /* for round robin */
197 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
198 CIRCLEQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
199 frags;
200 int qlen; /* fraq queue length */
201 struct callout_handle fragTimer; /* fraq queue check */
202 };
203 typedef struct ng_ppp_private *priv_p;
204
205 /* Netgraph node methods */
206 static ng_constructor_t ng_ppp_constructor;
207 static ng_rcvmsg_t ng_ppp_rcvmsg;
208 static ng_shutdown_t ng_ppp_rmnode;
209 static ng_newhook_t ng_ppp_newhook;
210 static ng_rcvdata_t ng_ppp_rcvdata;
211 static ng_disconnect_t ng_ppp_disconnect;
212
213 /* Helper functions */
214 static int ng_ppp_input(node_p node, int bypass,
215 int linkNum, struct mbuf *m, meta_p meta);
216 static int ng_ppp_output(node_p node, int bypass, int proto,
217 int linkNum, struct mbuf *m, meta_p meta);
218 static int ng_ppp_mp_input(node_p node, int linkNum,
219 struct mbuf *m, meta_p meta);
220 static int ng_ppp_check_packet(node_p node);
221 static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
222 static int ng_ppp_frag_process(node_p node);
223 static int ng_ppp_frag_trim(node_p node);
224 static void ng_ppp_frag_timeout(void *arg);
225 static void ng_ppp_frag_checkstale(node_p node);
226 static void ng_ppp_frag_reset(node_p node);
227 static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
228 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
229 static int ng_ppp_intcmp(const void *v1, const void *v2);
230 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
231 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
232 static int ng_ppp_config_valid(node_p node,
233 const struct ng_ppp_node_conf *newConf);
234 static void ng_ppp_update(node_p node, int newConf);
235 static void ng_ppp_start_frag_timer(node_p node);
236 static void ng_ppp_stop_frag_timer(node_p node);
237
238 /* Parse type for struct ng_ppp_link_conf */
239 static const struct ng_parse_struct_info
240 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO;
241 static const struct ng_parse_type ng_ppp_link_type = {
242 &ng_parse_struct_type,
243 &ng_ppp_link_type_info,
244 };
245
246 /* Parse type for struct ng_ppp_bund_conf */
247 static const struct ng_parse_struct_info
248 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO;
249 static const struct ng_parse_type ng_ppp_bund_type = {
250 &ng_parse_struct_type,
251 &ng_ppp_bund_type_info,
252 };
253
254 /* Parse type for struct ng_ppp_node_conf */
255 struct ng_parse_fixedarray_info ng_ppp_array_info = {
256 &ng_ppp_link_type,
257 NG_PPP_MAX_LINKS
258 };
259 static const struct ng_parse_type ng_ppp_link_array_type = {
260 &ng_parse_fixedarray_type,
261 &ng_ppp_array_info,
262 };
263 static const struct ng_parse_struct_info ng_ppp_conf_type_info
264 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
265 static const struct ng_parse_type ng_ppp_conf_type = {
266 &ng_parse_struct_type,
267 &ng_ppp_conf_type_info
268 };
269
270 /* Parse type for struct ng_ppp_link_stat */
271 static const struct ng_parse_struct_info
272 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO;
273 static const struct ng_parse_type ng_ppp_stats_type = {
274 &ng_parse_struct_type,
275 &ng_ppp_stats_type_info
276 };
277
278 /* List of commands and how to convert arguments to/from ASCII */
279 static const struct ng_cmdlist ng_ppp_cmds[] = {
280 {
281 NGM_PPP_COOKIE,
282 NGM_PPP_SET_CONFIG,
283 "setconfig",
284 &ng_ppp_conf_type,
285 NULL
286 },
287 {
288 NGM_PPP_COOKIE,
289 NGM_PPP_GET_CONFIG,
290 "getconfig",
291 NULL,
292 &ng_ppp_conf_type
293 },
294 {
295 NGM_PPP_COOKIE,
296 NGM_PPP_GET_LINK_STATS,
297 "getstats",
298 &ng_parse_int16_type,
299 &ng_ppp_stats_type
300 },
301 {
302 NGM_PPP_COOKIE,
303 NGM_PPP_CLR_LINK_STATS,
304 "clrstats",
305 &ng_parse_int16_type,
306 NULL
307 },
308 {
309 NGM_PPP_COOKIE,
310 NGM_PPP_GETCLR_LINK_STATS,
311 "getclrstats",
312 &ng_parse_int16_type,
313 &ng_ppp_stats_type
314 },
315 { 0 }
316 };
317
318 /* Node type descriptor */
319 static struct ng_type ng_ppp_typestruct = {
320 NG_VERSION,
321 NG_PPP_NODE_TYPE,
322 NULL,
323 ng_ppp_constructor,
324 ng_ppp_rcvmsg,
325 ng_ppp_rmnode,
326 ng_ppp_newhook,
327 NULL,
328 NULL,
329 ng_ppp_rcvdata,
330 ng_ppp_rcvdata,
331 ng_ppp_disconnect,
332 ng_ppp_cmds
333 };
334 NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
335
336 static int *compareLatencies; /* hack for ng_ppp_intcmp() */
337
338 /* Address and control field header */
339 static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
340
341 /* Maximum time we'll let a complete incoming packet sit in the queue */
342 static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
343
344 #define ERROUT(x) do { error = (x); goto done; } while (0)
345
346 /************************************************************************
347 NETGRAPH NODE STUFF
348 ************************************************************************/
349
350 /*
351 * Node type constructor
352 */
353 static int
354 ng_ppp_constructor(node_p *nodep)
355 {
356 priv_p priv;
357 int i, error;
358
359 /* Allocate private structure */
360 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK);
361 if (priv == NULL)
362 return (ENOMEM);
363 bzero(priv, sizeof(*priv));
364
365 /* Call generic node constructor */
366 if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) {
367 FREE(priv, M_NETGRAPH);
368 return (error);
369 }
370 (*nodep)->private = priv;
371
372 /* Initialize state */
373 CIRCLEQ_INIT(&priv->frags);
374 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
375 priv->links[i].seq = MP_NOSEQ;
376 callout_handle_init(&priv->fragTimer);
377
378 /* Done */
379 return (0);
380 }
381
382 /*
383 * Give our OK for a hook to be added
384 */
385 static int
386 ng_ppp_newhook(node_p node, hook_p hook, const char *name)
387 {
388 const priv_p priv = node->private;
389 int linkNum = -1;
390 hook_p *hookPtr = NULL;
391 int hookIndex = -1;
392
393 /* Figure out which hook it is */
394 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
395 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
396 const char *cp;
397 char *eptr;
398
399 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
400 if (!isdigit(*cp) || (cp[0] == '' && cp[1] != '\0'))
401 return (EINVAL);
402 linkNum = (int)strtoul(cp, &eptr, 10);
403 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
404 return (EINVAL);
405 hookPtr = &priv->links[linkNum].hook;
406 hookIndex = ~linkNum;
407 } else { /* must be a non-link hook */
408 int i;
409
410 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
411 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
412 hookPtr = &priv->hooks[i];
413 hookIndex = i;
414 break;
415 }
416 }
417 if (ng_ppp_hook_names[i] == NULL)
418 return (EINVAL); /* no such hook */
419 }
420
421 /* See if hook is already connected */
422 if (*hookPtr != NULL)
423 return (EISCONN);
424
425 /* Disallow more than one link unless multilink is enabled */
426 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
427 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
428 return (ENODEV);
429
430 /* OK */
431 *hookPtr = hook;
432 HOOK_INDEX(hook) = hookIndex;
433 ng_ppp_update(node, 0);
434 return (0);
435 }
436
437 /*
438 * Receive a control message
439 */
440 static int
441 ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg,
442 const char *raddr, struct ng_mesg **rptr)
443 {
444 const priv_p priv = node->private;
445 struct ng_mesg *resp = NULL;
446 int error = 0;
447
448 switch (msg->header.typecookie) {
449 case NGM_PPP_COOKIE:
450 switch (msg->header.cmd) {
451 case NGM_PPP_SET_CONFIG:
452 {
453 struct ng_ppp_node_conf *const conf =
454 (struct ng_ppp_node_conf *)msg->data;
455 int i;
456
457 /* Check for invalid or illegal config */
458 if (msg->header.arglen != sizeof(*conf))
459 ERROUT(EINVAL);
460 if (!ng_ppp_config_valid(node, conf))
461 ERROUT(EINVAL);
462
463 /* Copy config */
464 priv->conf = conf->bund;
465 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
466 priv->links[i].conf = conf->links[i];
467 ng_ppp_update(node, 1);
468 break;
469 }
470 case NGM_PPP_GET_CONFIG:
471 {
472 struct ng_ppp_node_conf *conf;
473 int i;
474
475 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
476 if (resp == NULL)
477 ERROUT(ENOMEM);
478 conf = (struct ng_ppp_node_conf *)resp->data;
479 conf->bund = priv->conf;
480 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
481 conf->links[i] = priv->links[i].conf;
482 break;
483 }
484 case NGM_PPP_GET_LINK_STATS:
485 case NGM_PPP_CLR_LINK_STATS:
486 case NGM_PPP_GETCLR_LINK_STATS:
487 {
488 struct ng_ppp_link_stat *stats;
489 u_int16_t linkNum;
490
491 if (msg->header.arglen != sizeof(u_int16_t))
492 ERROUT(EINVAL);
493 linkNum = *((u_int16_t *) msg->data);
494 if (linkNum >= NG_PPP_MAX_LINKS
495 && linkNum != NG_PPP_BUNDLE_LINKNUM)
496 ERROUT(EINVAL);
497 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ?
498 &priv->bundleStats : &priv->links[linkNum].stats;
499 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) {
500 NG_MKRESPONSE(resp, msg,
501 sizeof(struct ng_ppp_link_stat), M_NOWAIT);
502 if (resp == NULL)
503 ERROUT(ENOMEM);
504 bcopy(stats, resp->data, sizeof(*stats));
505 }
506 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS)
507 bzero(stats, sizeof(*stats));
508 break;
509 }
510 default:
511 error = EINVAL;
512 break;
513 }
514 break;
515 case NGM_VJC_COOKIE:
516 {
517 char path[NG_PATHLEN + 1];
518 node_p origNode;
519
520 if ((error = ng_path2node(node, raddr, &origNode, NULL)) != 0)
521 ERROUT(error);
522 snprintf(path, sizeof(path), "[%lx]:%s",
523 (long)node, NG_PPP_HOOK_VJC_IP);
524 return ng_send_msg(origNode, msg, path, rptr);
525 }
526 default:
527 error = EINVAL;
528 break;
529 }
530 if (rptr)
531 *rptr = resp;
532 else if (resp)
533 FREE(resp, M_NETGRAPH);
534
535 done:
536 FREE(msg, M_NETGRAPH);
537 return (error);
538 }
539
540 /*
541 * Receive data on a hook
542 */
543 static int
544 ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
545 {
546 const node_p node = hook->node;
547 const priv_p priv = node->private;
548 const int index = HOOK_INDEX(hook);
549 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
550 hook_p outHook = NULL;
551 int proto = 0, error;
552
553 /* Did it come from a link hook? */
554 if (index < 0) {
555 struct ng_ppp_link *link;
556
557 /* Convert index into a link number */
558 linkNum = (u_int16_t)~index;
559 KASSERT(linkNum < NG_PPP_MAX_LINKS,
560 ("%s: bogus index 0x%x", __FUNCTION__, index));
561 link = &priv->links[linkNum];
562
563 /* Stats */
564 link->stats.recvFrames++;
565 link->stats.recvOctets += m->m_pkthdr.len;
566
567 /* Strip address and control fields, if present */
568 if (m->m_pkthdr.len >= 2) {
569 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
570 NG_FREE_DATA(m, meta);
571 return (ENOBUFS);
572 }
573 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
574 m_adj(m, 2);
575 }
576
577 /* Dispatch incoming frame (if not enabled, to bypass) */
578 return ng_ppp_input(node,
579 !link->conf.enableLink, linkNum, m, meta);
580 }
581
582 /* Get protocol & check if data allowed from this hook */
583 switch (index) {
584
585 /* Outgoing data */
586 case HOOK_INDEX_ATALK:
587 if (!priv->conf.enableAtalk) {
588 NG_FREE_DATA(m, meta);
589 return (ENXIO);
590 }
591 proto = PROT_APPLETALK;
592 break;
593 case HOOK_INDEX_IPX:
594 if (!priv->conf.enableIPX) {
595 NG_FREE_DATA(m, meta);
596 return (ENXIO);
597 }
598 proto = PROT_IPX;
599 break;
600 case HOOK_INDEX_IPV6:
601 if (!priv->conf.enableIPv6) {
602 NG_FREE_DATA(m, meta);
603 return (ENXIO);
604 }
605 proto = PROT_IPV6;
606 break;
607 case HOOK_INDEX_INET:
608 case HOOK_INDEX_VJC_VJIP:
609 if (!priv->conf.enableIP) {
610 NG_FREE_DATA(m, meta);
611 return (ENXIO);
612 }
613 proto = PROT_IP;
614 break;
615 case HOOK_INDEX_VJC_COMP:
616 if (!priv->conf.enableVJCompression) {
617 NG_FREE_DATA(m, meta);
618 return (ENXIO);
619 }
620 proto = PROT_VJCOMP;
621 break;
622 case HOOK_INDEX_VJC_UNCOMP:
623 if (!priv->conf.enableVJCompression) {
624 NG_FREE_DATA(m, meta);
625 return (ENXIO);
626 }
627 proto = PROT_VJUNCOMP;
628 break;
629 case HOOK_INDEX_COMPRESS:
630 if (!priv->conf.enableCompression) {
631 NG_FREE_DATA(m, meta);
632 return (ENXIO);
633 }
634 proto = PROT_COMPD;
635 break;
636 case HOOK_INDEX_ENCRYPT:
637 if (!priv->conf.enableEncryption) {
638 NG_FREE_DATA(m, meta);
639 return (ENXIO);
640 }
641 proto = PROT_CRYPTD;
642 break;
643 case HOOK_INDEX_BYPASS:
644 if (m->m_pkthdr.len < 4) {
645 NG_FREE_DATA(m, meta);
646 return (EINVAL);
647 }
648 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
649 NG_FREE_META(meta);
650 return (ENOBUFS);
651 }
652 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
653 proto = ntohs(mtod(m, u_int16_t *)[1]);
654 m_adj(m, 4);
655 if (linkNum >= NG_PPP_MAX_LINKS
656 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
657 NG_FREE_DATA(m, meta);
658 return (EINVAL);
659 }
660 break;
661
662 /* Incoming data */
663 case HOOK_INDEX_VJC_IP:
664 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
665 NG_FREE_DATA(m, meta);
666 return (ENXIO);
667 }
668 break;
669 case HOOK_INDEX_DECOMPRESS:
670 if (!priv->conf.enableDecompression) {
671 NG_FREE_DATA(m, meta);
672 return (ENXIO);
673 }
674 break;
675 case HOOK_INDEX_DECRYPT:
676 if (!priv->conf.enableDecryption) {
677 NG_FREE_DATA(m, meta);
678 return (ENXIO);
679 }
680 break;
681 default:
682 panic("%s: bogus index 0x%x", __FUNCTION__, index);
683 }
684
685 /* Now figure out what to do with the frame */
686 switch (index) {
687
688 /* Outgoing data */
689 case HOOK_INDEX_INET:
690 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
691 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
692 break;
693 }
694 /* FALLTHROUGH */
695 case HOOK_INDEX_ATALK:
696 case HOOK_INDEX_IPV6:
697 case HOOK_INDEX_IPX:
698 case HOOK_INDEX_VJC_COMP:
699 case HOOK_INDEX_VJC_UNCOMP:
700 case HOOK_INDEX_VJC_VJIP:
701 if (priv->conf.enableCompression
702 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
703 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
704 NG_FREE_META(meta);
705 return (ENOBUFS);
706 }
707 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
708 break;
709 }
710 /* FALLTHROUGH */
711 case HOOK_INDEX_COMPRESS:
712 if (priv->conf.enableEncryption
713 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
714 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
715 NG_FREE_META(meta);
716 return (ENOBUFS);
717 }
718 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
719 break;
720 }
721 /* FALLTHROUGH */
722 case HOOK_INDEX_ENCRYPT:
723 return ng_ppp_output(node, 0,
724 proto, NG_PPP_BUNDLE_LINKNUM, m, meta);
725
726 case HOOK_INDEX_BYPASS:
727 return ng_ppp_output(node, 1, proto, linkNum, m, meta);
728
729 /* Incoming data */
730 case HOOK_INDEX_DECRYPT:
731 case HOOK_INDEX_DECOMPRESS:
732 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
733
734 case HOOK_INDEX_VJC_IP:
735 outHook = priv->hooks[HOOK_INDEX_INET];
736 break;
737 }
738
739 /* Send packet out hook */
740 NG_SEND_DATA(error, outHook, m, meta);
741 return (error);
742 }
743
744 /*
745 * Destroy node
746 */
747 static int
748 ng_ppp_rmnode(node_p node)
749 {
750 const priv_p priv = node->private;
751
752 /* Stop fragment queue timer */
753 ng_ppp_stop_frag_timer(node);
754
755 /* Take down netgraph node */
756 node->flags |= NG_INVALID;
757 ng_cutlinks(node);
758 ng_unname(node);
759 ng_ppp_frag_reset(node);
760 bzero(priv, sizeof(*priv));
761 FREE(priv, M_NETGRAPH);
762 node->private = NULL;
763 ng_unref(node); /* let the node escape */
764 return (0);
765 }
766
767 /*
768 * Hook disconnection
769 */
770 static int
771 ng_ppp_disconnect(hook_p hook)
772 {
773 const node_p node = hook->node;
774 const priv_p priv = node->private;
775 const int index = HOOK_INDEX(hook);
776
777 /* Zero out hook pointer */
778 if (index < 0)
779 priv->links[~index].hook = NULL;
780 else
781 priv->hooks[index] = NULL;
782
783 /* Update derived info (or go away if no hooks left) */
784 if (node->numhooks > 0)
785 ng_ppp_update(node, 0);
786 else
787 ng_rmnode(node);
788 return (0);
789 }
790
791 /************************************************************************
792 HELPER STUFF
793 ************************************************************************/
794
795 /*
796 * Handle an incoming frame. Extract the PPP protocol number
797 * and dispatch accordingly.
798 */
799 static int
800 ng_ppp_input(node_p node, int bypass, int linkNum, struct mbuf *m, meta_p meta)
801 {
802 const priv_p priv = node->private;
803 hook_p outHook = NULL;
804 int proto, error;
805
806 /* Extract protocol number */
807 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
808 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
809 NG_FREE_META(meta);
810 return (ENOBUFS);
811 }
812 proto = (proto << 8) + *mtod(m, u_char *);
813 m_adj(m, 1);
814 }
815 if (!PROT_VALID(proto)) {
816 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
817 priv->bundleStats.badProtos++;
818 else
819 priv->links[linkNum].stats.badProtos++;
820 NG_FREE_DATA(m, meta);
821 return (EINVAL);
822 }
823
824 /* Bypass frame? */
825 if (bypass)
826 goto bypass;
827
828 /* Check protocol */
829 switch (proto) {
830 case PROT_COMPD:
831 if (priv->conf.enableDecompression)
832 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
833 break;
834 case PROT_CRYPTD:
835 if (priv->conf.enableDecryption)
836 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
837 break;
838 case PROT_VJCOMP:
839 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
840 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
841 break;
842 case PROT_VJUNCOMP:
843 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
844 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
845 break;
846 case PROT_MP:
847 if (priv->conf.enableMultilink
848 && linkNum != NG_PPP_BUNDLE_LINKNUM)
849 return ng_ppp_mp_input(node, linkNum, m, meta);
850 break;
851 case PROT_APPLETALK:
852 if (priv->conf.enableAtalk)
853 outHook = priv->hooks[HOOK_INDEX_ATALK];
854 break;
855 case PROT_IPX:
856 if (priv->conf.enableIPX)
857 outHook = priv->hooks[HOOK_INDEX_IPX];
858 break;
859 case PROT_IP:
860 if (priv->conf.enableIP)
861 outHook = priv->hooks[HOOK_INDEX_INET];
862 break;
863 case PROT_IPV6:
864 if (priv->conf.enableIPv6)
865 outHook = priv->hooks[HOOK_INDEX_IPV6];
866 break;
867 }
868
869 bypass:
870 /* For unknown/inactive protocols, forward out the bypass hook */
871 if (outHook == NULL) {
872 u_int16_t hdr[2];
873
874 hdr[0] = htons(linkNum);
875 hdr[1] = htons((u_int16_t)proto);
876 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
877 NG_FREE_META(meta);
878 return (ENOBUFS);
879 }
880 outHook = priv->hooks[HOOK_INDEX_BYPASS];
881 }
882
883 /* Forward frame */
884 NG_SEND_DATA(error, outHook, m, meta);
885 return (error);
886 }
887
888 /*
889 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM
890 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
891 */
892 static int
893 ng_ppp_output(node_p node, int bypass,
894 int proto, int linkNum, struct mbuf *m, meta_p meta)
895 {
896 const priv_p priv = node->private;
897 struct ng_ppp_link *link;
898 int len, error;
899
900 /* If not doing MP, map bundle virtual link to (the only) link */
901 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
902 linkNum = priv->activeLinks[0];
903
904 /* Get link pointer (optimization) */
905 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
906 &priv->links[linkNum] : NULL;
907
908 /* Check link status (if real) */
909 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
910 if (!bypass && !link->conf.enableLink) {
911 NG_FREE_DATA(m, meta);
912 return (ENXIO);
913 }
914 if (link->hook == NULL) {
915 NG_FREE_DATA(m, meta);
916 return (ENETDOWN);
917 }
918 }
919
920 /* Prepend protocol number, possibly compressed */
921 if ((m = ng_ppp_addproto(m, proto,
922 linkNum == NG_PPP_BUNDLE_LINKNUM
923 || link->conf.enableProtoComp)) == NULL) {
924 NG_FREE_META(meta);
925 return (ENOBUFS);
926 }
927
928 /* Special handling for the MP virtual link */
929 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
930 return ng_ppp_mp_output(node, m, meta);
931
932 /* Prepend address and control field (unless compressed) */
933 if (proto == PROT_LCP || !link->conf.enableACFComp) {
934 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
935 NG_FREE_META(meta);
936 return (ENOBUFS);
937 }
938 }
939
940 /* Deliver frame */
941 len = m->m_pkthdr.len;
942 NG_SEND_DATA(error, link->hook, m, meta);
943
944 /* Update stats and 'bytes in queue' counter */
945 if (error == 0) {
946 link->stats.xmitFrames++;
947 link->stats.xmitOctets += len;
948 link->bytesInQueue += len;
949 getmicrouptime(&link->lastWrite);
950 }
951 return error;
952 }
953
954 /*
955 * Handle an incoming multi-link fragment
956 *
957 * The fragment reassembly algorithm is somewhat complex. This is mainly
958 * because we are required not to reorder the reconstructed packets, yet
959 * fragments are only guaranteed to arrive in order on a per-link basis.
960 * In other words, when we have a complete packet ready, but the previous
961 * packet is still incomplete, we have to decide between delivering the
962 * complete packet and throwing away the incomplete one, or waiting to
963 * see if the remainder of the incomplete one arrives, at which time we
964 * can deliver both packets, in order.
965 *
966 * This problem is exacerbated by "sequence number slew", which is when
967 * the sequence numbers coming in from different links are far apart from
968 * each other. In particular, certain unnamed equipment (*cough* Ascend)
969 * has been seen to generate sequence number slew of up to 10 on an ISDN
970 * 2B-channel MP link. There is nothing invalid about sequence number slew
971 * but it makes the reasssembly process have to work harder.
972 *
973 * However, the peer is required to transmit fragments in order on each
974 * link. That means if we define MSEQ as the minimum over all links of
975 * the highest sequence number received on that link, then we can always
976 * give up any hope of receiving a fragment with sequence number < MSEQ in
977 * the future (all of this using 'wraparound' sequence number space).
978 * Therefore we can always immediately throw away incomplete packets
979 * missing fragments with sequence numbers < MSEQ.
980 *
981 * Here is an overview of our algorithm:
982 *
983 * o Received fragments are inserted into a queue, for which we
984 * maintain these invariants between calls to this function:
985 *
986 * - Fragments are ordered in the queue by sequence number
987 * - If a complete packet is at the head of the queue, then
988 * the first fragment in the packet has seq# > MSEQ + 1
989 * (otherwise, we could deliver it immediately)
990 * - If any fragments have seq# < MSEQ, then they are necessarily
991 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
992 * we can throw them away because they'll never be completed)
993 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
994 *
995 * o We have a periodic timer that checks the queue for the first
996 * complete packet that has been sitting in the queue "too long".
997 * When one is detected, all previous (incomplete) fragments are
998 * discarded, their missing fragments are declared lost and MSEQ
999 * is increased.
1000 *
1001 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1002 * because we've already delcared it lost.
1003 *
1004 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1005 */
1006 static int
1007 ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
1008 {
1009 const priv_p priv = node->private;
1010 struct ng_ppp_link *const link = &priv->links[linkNum];
1011 struct ng_ppp_frag frag0, *frag = &frag0;
1012 struct ng_ppp_frag *qent;
1013 int i, diff, inserted;
1014
1015 /* Extract fragment information from MP header */
1016 if (priv->conf.recvShortSeq) {
1017 u_int16_t shdr;
1018
1019 if (m->m_pkthdr.len < 2) {
1020 link->stats.runts++;
1021 NG_FREE_DATA(m, meta);
1022 return (EINVAL);
1023 }
1024 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1025 NG_FREE_META(meta);
1026 return (ENOBUFS);
1027 }
1028 shdr = ntohs(*mtod(m, u_int16_t *));
1029 frag->seq = shdr & MP_SHORT_SEQ_MASK;
1030 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1031 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1032 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1033 m_adj(m, 2);
1034 } else {
1035 u_int32_t lhdr;
1036
1037 if (m->m_pkthdr.len < 4) {
1038 link->stats.runts++;
1039 NG_FREE_DATA(m, meta);
1040 return (EINVAL);
1041 }
1042 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1043 NG_FREE_META(meta);
1044 return (ENOBUFS);
1045 }
1046 lhdr = ntohl(*mtod(m, u_int32_t *));
1047 frag->seq = lhdr & MP_LONG_SEQ_MASK;
1048 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1049 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1050 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1051 m_adj(m, 4);
1052 }
1053 frag->data = m;
1054 frag->meta = meta;
1055 getmicrouptime(&frag->timestamp);
1056
1057 /* If sequence number is < MSEQ, we've already declared this
1058 fragment as lost, so we have no choice now but to drop it */
1059 if (diff < 0) {
1060 link->stats.dropFragments++;
1061 NG_FREE_DATA(m, meta);
1062 return (0);
1063 }
1064
1065 /* Update highest received sequence number on this link and MSEQ */
1066 priv->mseq = link->seq = frag->seq;
1067 for (i = 0; i < priv->numActiveLinks; i++) {
1068 struct ng_ppp_link *const alink =
1069 &priv->links[priv->activeLinks[i]];
1070
1071 if (MP_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1072 priv->mseq = alink->seq;
1073 }
1074
1075 /* Allocate a new frag struct for the queue */
1076 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT);
1077 if (frag == NULL) {
1078 NG_FREE_DATA(m, meta);
1079 ng_ppp_frag_process(node);
1080 return (ENOMEM);
1081 }
1082 *frag = frag0;
1083
1084 /* Add fragment to queue, which is sorted by sequence number */
1085 inserted = 0;
1086 CIRCLEQ_FOREACH_REVERSE(qent, &priv->frags, f_qent) {
1087 diff = MP_SEQ_DIFF(priv, frag->seq, qent->seq);
1088 if (diff > 0) {
1089 CIRCLEQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1090 inserted = 1;
1091 break;
1092 } else if (diff == 0) { /* should never happen! */
1093 link->stats.dupFragments++;
1094 NG_FREE_DATA(frag->data, frag->meta);
1095 FREE(frag, M_NETGRAPH);
1096 return (EINVAL);
1097 }
1098 }
1099 if (!inserted)
1100 CIRCLEQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1101 priv->qlen++;
1102
1103 /* Process the queue */
1104 return ng_ppp_frag_process(node);
1105 }
1106
1107 /*
1108 * Examine our list of fragments, and determine if there is a
1109 * complete and deliverable packet at the head of the list.
1110 * Return 1 if so, zero otherwise.
1111 */
1112 static int
1113 ng_ppp_check_packet(node_p node)
1114 {
1115 const priv_p priv = node->private;
1116 struct ng_ppp_frag *qent, *qnext;
1117
1118 /* Check for empty queue */
1119 if (CIRCLEQ_EMPTY(&priv->frags))
1120 return (0);
1121
1122 /* Check first fragment is the start of a deliverable packet */
1123 qent = CIRCLEQ_FIRST(&priv->frags);
1124 if (!qent->first || MP_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1125 return (0);
1126
1127 /* Check that all the fragments are there */
1128 while (!qent->last) {
1129 qnext = CIRCLEQ_NEXT(qent, f_qent);
1130 if (qnext == (void *)&priv->frags) /* end of queue */
1131 return (0);
1132 if (qnext->seq != MP_NEXT_SEQ(priv, qent->seq))
1133 return (0);
1134 qent = qnext;
1135 }
1136
1137 /* Got one */
1138 return (1);
1139 }
1140
1141 /*
1142 * Pull a completed packet off the head of the incoming fragment queue.
1143 * This assumes there is a completed packet there to pull off.
1144 */
1145 static void
1146 ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1147 {
1148 const priv_p priv = node->private;
1149 struct ng_ppp_frag *qent, *qnext;
1150 struct mbuf *m = NULL, *tail;
1151
1152 qent = CIRCLEQ_FIRST(&priv->frags);
1153 KASSERT(!CIRCLEQ_EMPTY(&priv->frags) && qent->first,
1154 ("%s: no packet", __FUNCTION__));
1155 for (tail = NULL; qent != NULL; qent = qnext) {
1156 qnext = CIRCLEQ_NEXT(qent, f_qent);
1157 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1158 ("%s: empty q", __FUNCTION__));
1159 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1160 if (tail == NULL) {
1161 tail = m = qent->data;
1162 *metap = qent->meta; /* inherit first frag's meta */
1163 } else {
1164 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1165 tail->m_next = qent->data;
1166 NG_FREE_META(qent->meta); /* drop other frags' metas */
1167 }
1168 while (tail->m_next != NULL)
1169 tail = tail->m_next;
1170 if (qent->last)
1171 qnext = NULL;
1172 FREE(qent, M_NETGRAPH);
1173 priv->qlen--;
1174 }
1175 *mp = m;
1176 }
1177
1178 /*
1179 * Trim fragments from the queue whose packets can never be completed.
1180 * This assumes a complete packet is NOT at the beginning of the queue.
1181 * Returns 1 if fragments were removed, zero otherwise.
1182 */
1183 static int
1184 ng_ppp_frag_trim(node_p node)
1185 {
1186 const priv_p priv = node->private;
1187 struct ng_ppp_frag *qent, *qnext = NULL;
1188 int removed = 0;
1189
1190 /* Scan for "dead" fragments and remove them */
1191 while (1) {
1192 int dead = 0;
1193
1194 /* If queue is empty, we're done */
1195 if (CIRCLEQ_EMPTY(&priv->frags))
1196 break;
1197
1198 /* Determine whether first fragment can ever be completed */
1199 CIRCLEQ_FOREACH(qent, &priv->frags, f_qent) {
1200 if (MP_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1201 break;
1202 qnext = CIRCLEQ_NEXT(qent, f_qent);
1203 KASSERT(qnext != (void*)&priv->frags,
1204 ("%s: last frag < MSEQ?", __FUNCTION__));
1205 if (qnext->seq != MP_NEXT_SEQ(priv, qent->seq)
1206 || qent->last || qnext->first) {
1207 dead = 1;
1208 break;
1209 }
1210 }
1211 if (!dead)
1212 break;
1213
1214 /* Remove fragment and all others in the same packet */
1215 while ((qent = CIRCLEQ_FIRST(&priv->frags)) != qnext) {
1216 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1217 ("%s: empty q", __FUNCTION__));
1218 priv->bundleStats.dropFragments++;
1219 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1220 NG_FREE_DATA(qent->data, qent->meta);
1221 FREE(qent, M_NETGRAPH);
1222 priv->qlen--;
1223 removed = 1;
1224 }
1225 }
1226 return (removed);
1227 }
1228
1229 /*
1230 * Run the queue, restoring the queue invariants
1231 */
1232 static int
1233 ng_ppp_frag_process(node_p node)
1234 {
1235 const priv_p priv = node->private;
1236 struct mbuf *m;
1237 meta_p meta;
1238
1239 /* Deliver any deliverable packets */
1240 while (ng_ppp_check_packet(node)) {
1241 ng_ppp_get_packet(node, &m, &meta);
1242 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1243 }
1244
1245 /* Delete dead fragments and try again */
1246 if (ng_ppp_frag_trim(node)) {
1247 while (ng_ppp_check_packet(node)) {
1248 ng_ppp_get_packet(node, &m, &meta);
1249 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1250 }
1251 }
1252
1253 /* Check for stale fragments while we're here */
1254 ng_ppp_frag_checkstale(node);
1255
1256 /* Check queue length */
1257 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1258 struct ng_ppp_frag *qent;
1259 int i;
1260
1261 /* Get oldest fragment */
1262 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1263 ("%s: empty q", __FUNCTION__));
1264 qent = CIRCLEQ_FIRST(&priv->frags);
1265
1266 /* Bump MSEQ if necessary */
1267 if (MP_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1268 priv->mseq = qent->seq;
1269 for (i = 0; i < priv->numActiveLinks; i++) {
1270 struct ng_ppp_link *const alink =
1271 &priv->links[priv->activeLinks[i]];
1272
1273 if (MP_SEQ_DIFF(priv,
1274 alink->seq, priv->mseq) < 0)
1275 alink->seq = priv->mseq;
1276 }
1277 }
1278
1279 /* Drop it */
1280 priv->bundleStats.dropFragments++;
1281 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1282 NG_FREE_DATA(qent->data, qent->meta);
1283 FREE(qent, M_NETGRAPH);
1284 priv->qlen--;
1285
1286 /* Process queue again */
1287 return ng_ppp_frag_process(node);
1288 }
1289
1290 /* Done */
1291 return (0);
1292 }
1293
1294 /*
1295 * Check for 'stale' completed packets that need to be delivered
1296 *
1297 * If a link goes down or has a temporary failure, MSEQ can get
1298 * "stuck", because no new incoming fragments appear on that link.
1299 * This can cause completed packets to never get delivered if
1300 * their sequence numbers are all > MSEQ + 1.
1301 *
1302 * This routine checks how long all of the completed packets have
1303 * been sitting in the queue, and if too long, removes fragments
1304 * from the queue and increments MSEQ to allow them to be delivered.
1305 */
1306 static void
1307 ng_ppp_frag_checkstale(node_p node)
1308 {
1309 const priv_p priv = node->private;
1310 struct ng_ppp_frag *qent, *beg, *end;
1311 struct timeval now, age;
1312 struct mbuf *m;
1313 meta_p meta;
1314 int i, seq;
1315
1316 now.tv_sec = 0; /* uninitialized state */
1317 while (1) {
1318
1319 /* If queue is empty, we're done */
1320 if (CIRCLEQ_EMPTY(&priv->frags))
1321 break;
1322
1323 /* Find the first complete packet in the queue */
1324 beg = end = NULL;
1325 seq = CIRCLEQ_FIRST(&priv->frags)->seq;
1326 CIRCLEQ_FOREACH(qent, &priv->frags, f_qent) {
1327 if (qent->first)
1328 beg = qent;
1329 else if (qent->seq != seq)
1330 beg = NULL;
1331 if (beg != NULL && qent->last) {
1332 end = qent;
1333 break;
1334 }
1335 seq = MP_NEXT_SEQ(priv, seq);
1336 }
1337
1338 /* If none found, exit */
1339 if (end == NULL)
1340 break;
1341
1342 /* Get current time (we assume we've been up for >= 1 second) */
1343 if (now.tv_sec == 0)
1344 getmicrouptime(&now);
1345
1346 /* Check if packet has been queued too long */
1347 age = now;
1348 timevalsub(&age, &beg->timestamp);
1349 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1350 break;
1351
1352 /* Throw away junk fragments in front of the completed packet */
1353 while ((qent = CIRCLEQ_FIRST(&priv->frags)) != beg) {
1354 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1355 ("%s: empty q", __FUNCTION__));
1356 priv->bundleStats.dropFragments++;
1357 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1358 NG_FREE_DATA(qent->data, qent->meta);
1359 FREE(qent, M_NETGRAPH);
1360 priv->qlen--;
1361 }
1362
1363 /* Extract completed packet */
1364 ng_ppp_get_packet(node, &m, &meta);
1365
1366 /* Bump MSEQ if necessary */
1367 if (MP_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) {
1368 priv->mseq = end->seq;
1369 for (i = 0; i < priv->numActiveLinks; i++) {
1370 struct ng_ppp_link *const alink =
1371 &priv->links[priv->activeLinks[i]];
1372
1373 if (MP_SEQ_DIFF(priv,
1374 alink->seq, priv->mseq) < 0)
1375 alink->seq = priv->mseq;
1376 }
1377 }
1378
1379 /* Deliver packet */
1380 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1381 }
1382 }
1383
1384 /*
1385 * Periodically call ng_ppp_frag_checkstale()
1386 */
1387 static void
1388 ng_ppp_frag_timeout(void *arg)
1389 {
1390 const node_p node = arg;
1391 const priv_p priv = node->private;
1392 int s = splnet();
1393
1394 /* Handle the race where shutdown happens just before splnet() above */
1395 if ((node->flags & NG_INVALID) != 0) {
1396 ng_unref(node);
1397 splx(s);
1398 return;
1399 }
1400
1401 /* Reset timer state after timeout */
1402 KASSERT(priv->timerActive, ("%s: !timerActive", __FUNCTION__));
1403 priv->timerActive = 0;
1404 KASSERT(node->refs > 1, ("%s: refs=%d", __FUNCTION__, node->refs));
1405 ng_unref(node);
1406
1407 /* Start timer again */
1408 ng_ppp_start_frag_timer(node);
1409
1410 /* Scan the fragment queue */
1411 ng_ppp_frag_checkstale(node);
1412 splx(s);
1413 }
1414
1415 /*
1416 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1417 * the frame across the individual PPP links and do so.
1418 */
1419 static int
1420 ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1421 {
1422 const priv_p priv = node->private;
1423 int distrib[NG_PPP_MAX_LINKS];
1424 int firstFragment;
1425 int activeLinkNum;
1426
1427 /* At least one link must be active */
1428 if (priv->numActiveLinks == 0) {
1429 NG_FREE_DATA(m, meta);
1430 return (ENETDOWN);
1431 }
1432
1433 /* Round-robin strategy */
1434 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1435 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1436 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1437 distrib[activeLinkNum] = m->m_pkthdr.len;
1438 goto deliver;
1439 }
1440
1441 /* Strategy when all links are equivalent (optimize the common case) */
1442 if (priv->allLinksEqual) {
1443 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1444 int i, remain;
1445
1446 for (i = 0; i < priv->numActiveLinks; i++)
1447 distrib[priv->lastLink++ % priv->numActiveLinks]
1448 = fraction;
1449 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1450 while (remain > 0) {
1451 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1452 remain--;
1453 }
1454 goto deliver;
1455 }
1456
1457 /* Strategy when all links are not equivalent */
1458 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1459
1460 deliver:
1461 /* Update stats */
1462 priv->bundleStats.xmitFrames++;
1463 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1464
1465 /* Send alloted portions of frame out on the link(s) */
1466 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1467 activeLinkNum >= 0; activeLinkNum--) {
1468 const int linkNum = priv->activeLinks[activeLinkNum];
1469 struct ng_ppp_link *const link = &priv->links[linkNum];
1470
1471 /* Deliver fragment(s) out the next link */
1472 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1473 int len, lastFragment, error;
1474 struct mbuf *m2;
1475 meta_p meta2;
1476
1477 /* Calculate fragment length; don't exceed link MTU */
1478 len = distrib[activeLinkNum];
1479 if (len > link->conf.mru)
1480 len = link->conf.mru;
1481 distrib[activeLinkNum] -= len;
1482 lastFragment = (len == m->m_pkthdr.len);
1483
1484 /* Split off next fragment as "m2" */
1485 m2 = m;
1486 if (!lastFragment) {
1487 struct mbuf *n = m_split(m, len, M_NOWAIT);
1488
1489 if (n == NULL) {
1490 NG_FREE_DATA(m, meta);
1491 return (ENOMEM);
1492 }
1493 m = n;
1494 }
1495
1496 /* Prepend MP header */
1497 if (priv->conf.xmitShortSeq) {
1498 u_int16_t shdr;
1499
1500 shdr = priv->xseq;
1501 priv->xseq =
1502 (priv->xseq + 1) % MP_SHORT_SEQ_MASK;
1503 if (firstFragment)
1504 shdr |= MP_SHORT_FIRST_FLAG;
1505 if (lastFragment)
1506 shdr |= MP_SHORT_LAST_FLAG;
1507 shdr = htons(shdr);
1508 m2 = ng_ppp_prepend(m2, &shdr, 2);
1509 } else {
1510 u_int32_t lhdr;
1511
1512 lhdr = priv->xseq;
1513 priv->xseq =
1514 (priv->xseq + 1) % MP_LONG_SEQ_MASK;
1515 if (firstFragment)
1516 lhdr |= MP_LONG_FIRST_FLAG;
1517 if (lastFragment)
1518 lhdr |= MP_LONG_LAST_FLAG;
1519 lhdr = htonl(lhdr);
1520 m2 = ng_ppp_prepend(m2, &lhdr, 4);
1521 }
1522 if (m2 == NULL) {
1523 if (!lastFragment)
1524 m_freem(m);
1525 NG_FREE_META(meta);
1526 return (ENOBUFS);
1527 }
1528
1529 /* Copy the meta information, if any */
1530 meta2 = lastFragment ? meta : ng_copy_meta(meta);
1531
1532 /* Send fragment */
1533 error = ng_ppp_output(node, 0,
1534 PROT_MP, linkNum, m2, meta2);
1535 if (error != 0) {
1536 if (!lastFragment)
1537 NG_FREE_DATA(m, meta);
1538 return (error);
1539 }
1540 }
1541 }
1542
1543 /* Done */
1544 return (0);
1545 }
1546
1547 /*
1548 * Computing the optimal fragmentation
1549 * -----------------------------------
1550 *
1551 * This routine tries to compute the optimal fragmentation pattern based
1552 * on each link's latency, bandwidth, and calculated additional latency.
1553 * The latter quantity is the additional latency caused by previously
1554 * written data that has not been transmitted yet.
1555 *
1556 * This algorithm is only useful when not all of the links have the
1557 * same latency and bandwidth values.
1558 *
1559 * The essential idea is to make the last bit of each fragment of the
1560 * frame arrive at the opposite end at the exact same time. This greedy
1561 * algorithm is optimal, in that no other scheduling could result in any
1562 * packet arriving any sooner unless packets are delivered out of order.
1563 *
1564 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and
1565 * latency l_i (in miliseconds). Consider the function function f_i(t)
1566 * which is equal to the number of bytes that will have arrived at
1567 * the peer after t miliseconds if we start writing continuously at
1568 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i).
1569 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i).
1570 * Note that the y-intersect is always <= zero because latency can't be
1571 * negative. Note also that really the function is f_i(t) except when
1572 * f_i(t) is negative, in which case the function is zero. To take
1573 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }.
1574 * So the actual number of bytes that will have arrived at the peer after
1575 * t miliseconds is f_i(t) * Q_i(t).
1576 *
1577 * At any given time, each link has some additional latency a_i >= 0
1578 * due to previously written fragment(s) which are still in the queue.
1579 * This value is easily computed from the time since last transmission,
1580 * the previous latency value, the number of bytes written, and the
1581 * link's bandwidth.
1582 *
1583 * Assume that l_i includes any a_i already, and that the links are
1584 * sorted by latency, so that l_i <= l_{i+1}.
1585 *
1586 * Let N be the total number of bytes in the current frame we are sending.
1587 *
1588 * Suppose we were to start writing bytes at time t = 0 on all links
1589 * simultaneously, which is the most we can possibly do. Then let
1590 * F(t) be equal to the total number of bytes received by the peer
1591 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)).
1592 *
1593 * Our goal is simply this: fragment the frame across the links such
1594 * that the peer is able to reconstruct the completed frame as soon as
1595 * possible, i.e., at the least possible value of t. Call this value t_0.
1596 *
1597 * Then it follows that F(t_0) = N. Our strategy is first to find the value
1598 * of t_0, and then deduce how many bytes to write to each link.
1599 *
1600 * Rewriting F(t_0):
1601 *
1602 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) )
1603 *
1604 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will
1605 * lie in one of these ranges. To find it, we just need to find the i such
1606 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values
1607 * for Q_i() in this range, plug in the remaining values, solving for t_0.
1608 *
1609 * Once t_0 is known, then the number of bytes to send on link i is
1610 * just f_i(t_0) * Q_i(t_0).
1611 *
1612 * In other words, we start allocating bytes to the links one at a time.
1613 * We keep adding links until the frame is completely sent. Some links
1614 * may not get any bytes because their latency is too high.
1615 *
1616 * Is all this work really worth the trouble? Depends on the situation.
1617 * The bigger the ratio of computer speed to link speed, and the more
1618 * important total bundle latency is (e.g., for interactive response time),
1619 * the more it's worth it. There is however the cost of calling this
1620 * function for every frame. The running time is O(n^2) where n is the
1621 * number of links that receive a non-zero number of bytes.
1622 *
1623 * Since latency is measured in miliseconds, the "resolution" of this
1624 * algorithm is one milisecond.
1625 *
1626 * To avoid this algorithm altogether, configure all links to have the
1627 * same latency and bandwidth.
1628 */
1629 static void
1630 ng_ppp_mp_strategy(node_p node, int len, int *distrib)
1631 {
1632 const priv_p priv = node->private;
1633 int latency[NG_PPP_MAX_LINKS];
1634 int sortByLatency[NG_PPP_MAX_LINKS];
1635 int activeLinkNum;
1636 int t0, total, topSum, botSum;
1637 struct timeval now;
1638 int i, numFragments;
1639
1640 /* If only one link, this gets real easy */
1641 if (priv->numActiveLinks == 1) {
1642 distrib[0] = len;
1643 return;
1644 }
1645
1646 /* Get current time */
1647 getmicrouptime(&now);
1648
1649 /* Compute latencies for each link at this point in time */
1650 for (activeLinkNum = 0;
1651 activeLinkNum < priv->numActiveLinks; activeLinkNum++) {
1652 struct ng_ppp_link *alink;
1653 struct timeval diff;
1654 int xmitBytes;
1655
1656 /* Start with base latency value */
1657 alink = &priv->links[priv->activeLinks[activeLinkNum]];
1658 latency[activeLinkNum] = alink->conf.latency;
1659 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */
1660
1661 /* Any additional latency? */
1662 if (alink->bytesInQueue == 0)
1663 continue;
1664
1665 /* Compute time delta since last write */
1666 diff = now;
1667 timevalsub(&diff, &alink->lastWrite);
1668 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */
1669 alink->bytesInQueue = 0;
1670 continue;
1671 }
1672
1673 /* How many bytes could have transmitted since last write? */
1674 xmitBytes = (alink->conf.bandwidth * diff.tv_sec)
1675 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100;
1676 alink->bytesInQueue -= xmitBytes;
1677 if (alink->bytesInQueue < 0)
1678 alink->bytesInQueue = 0;
1679 else
1680 latency[activeLinkNum] +=
1681 (100 * alink->bytesInQueue) / alink->conf.bandwidth;
1682 }
1683
1684 /* Sort active links by latency */
1685 compareLatencies = latency;
1686 qsort(sortByLatency,
1687 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp);
1688 compareLatencies = NULL;
1689
1690 /* Find the interval we need (add links in sortByLatency[] order) */
1691 for (numFragments = 1;
1692 numFragments < priv->numActiveLinks; numFragments++) {
1693 for (total = i = 0; i < numFragments; i++) {
1694 int flowTime;
1695
1696 flowTime = latency[sortByLatency[numFragments]]
1697 - latency[sortByLatency[i]];
1698 total += ((flowTime * priv->links[
1699 priv->activeLinks[sortByLatency[i]]].conf.bandwidth)
1700 + 99) / 100;
1701 }
1702 if (total >= len)
1703 break;
1704 }
1705
1706 /* Solve for t_0 in that interval */
1707 for (topSum = botSum = i = 0; i < numFragments; i++) {
1708 int bw = priv->links[
1709 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1710
1711 topSum += latency[sortByLatency[i]] * bw; /* / 100 */
1712 botSum += bw; /* / 100 */
1713 }
1714 t0 = ((len * 100) + topSum + botSum / 2) / botSum;
1715
1716 /* Compute f_i(t_0) all i */
1717 bzero(distrib, priv->numActiveLinks * sizeof(*distrib));
1718 for (total = i = 0; i < numFragments; i++) {
1719 int bw = priv->links[
1720 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1721
1722 distrib[sortByLatency[i]] =
1723 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100;
1724 total += distrib[sortByLatency[i]];
1725 }
1726
1727 /* Deal with any rounding error */
1728 if (total < len) {
1729 struct ng_ppp_link *fastLink =
1730 &priv->links[priv->activeLinks[sortByLatency[0]]];
1731 int fast = 0;
1732
1733 /* Find the fastest link */
1734 for (i = 1; i < numFragments; i++) {
1735 struct ng_ppp_link *const link =
1736 &priv->links[priv->activeLinks[sortByLatency[i]]];
1737
1738 if (link->conf.bandwidth > fastLink->conf.bandwidth) {
1739 fast = i;
1740 fastLink = link;
1741 }
1742 }
1743 distrib[sortByLatency[fast]] += len - total;
1744 } else while (total > len) {
1745 struct ng_ppp_link *slowLink =
1746 &priv->links[priv->activeLinks[sortByLatency[0]]];
1747 int delta, slow = 0;
1748
1749 /* Find the slowest link that still has bytes to remove */
1750 for (i = 1; i < numFragments; i++) {
1751 struct ng_ppp_link *const link =
1752 &priv->links[priv->activeLinks[sortByLatency[i]]];
1753
1754 if (distrib[sortByLatency[slow]] == 0
1755 || (distrib[sortByLatency[i]] > 0
1756 && link->conf.bandwidth <
1757 slowLink->conf.bandwidth)) {
1758 slow = i;
1759 slowLink = link;
1760 }
1761 }
1762 delta = total - len;
1763 if (delta > distrib[sortByLatency[slow]])
1764 delta = distrib[sortByLatency[slow]];
1765 distrib[sortByLatency[slow]] -= delta;
1766 total -= delta;
1767 }
1768 }
1769
1770 /*
1771 * Compare two integers
1772 */
1773 static int
1774 ng_ppp_intcmp(const void *v1, const void *v2)
1775 {
1776 const int index1 = *((const int *) v1);
1777 const int index2 = *((const int *) v2);
1778
1779 return compareLatencies[index1] - compareLatencies[index2];
1780 }
1781
1782 /*
1783 * Prepend a possibly compressed PPP protocol number in front of a frame
1784 */
1785 static struct mbuf *
1786 ng_ppp_addproto(struct mbuf *m, int proto, int compOK)
1787 {
1788 if (compOK && PROT_COMPRESSABLE(proto)) {
1789 u_char pbyte = (u_char)proto;
1790
1791 return ng_ppp_prepend(m, &pbyte, 1);
1792 } else {
1793 u_int16_t pword = htons((u_int16_t)proto);
1794
1795 return ng_ppp_prepend(m, &pword, 2);
1796 }
1797 }
1798
1799 /*
1800 * Prepend some bytes to an mbuf
1801 */
1802 static struct mbuf *
1803 ng_ppp_prepend(struct mbuf *m, const void *buf, int len)
1804 {
1805 M_PREPEND(m, len, M_NOWAIT);
1806 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL))
1807 return (NULL);
1808 bcopy(buf, mtod(m, u_char *), len);
1809 return (m);
1810 }
1811
1812 /*
1813 * Update private information that is derived from other private information
1814 */
1815 static void
1816 ng_ppp_update(node_p node, int newConf)
1817 {
1818 const priv_p priv = node->private;
1819 int i;
1820
1821 /* Update active status for VJ Compression */
1822 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL
1823 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL
1824 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL
1825 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL;
1826
1827 /* Increase latency for each link an amount equal to one MP header */
1828 if (newConf) {
1829 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1830 int hdrBytes;
1831
1832 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2)
1833 + (priv->links[i].conf.enableProtoComp ? 1 : 2)
1834 + (priv->conf.xmitShortSeq ? 2 : 4);
1835 priv->links[i].conf.latency +=
1836 ((hdrBytes * priv->links[i].conf.bandwidth) + 50)
1837 / 100;
1838 }
1839 }
1840
1841 /* Update list of active links */
1842 bzero(&priv->activeLinks, sizeof(priv->activeLinks));
1843 priv->numActiveLinks = 0;
1844 priv->allLinksEqual = 1;
1845 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1846 struct ng_ppp_link *const link = &priv->links[i];
1847
1848 /* Is link active? */
1849 if (link->conf.enableLink && link->hook != NULL) {
1850 struct ng_ppp_link *link0;
1851
1852 /* Add link to list of active links */
1853 priv->activeLinks[priv->numActiveLinks++] = i;
1854 link0 = &priv->links[priv->activeLinks[0]];
1855
1856 /* Determine if all links are still equal */
1857 if (link->conf.latency != link0->conf.latency
1858 || link->conf.bandwidth != link0->conf.bandwidth)
1859 priv->allLinksEqual = 0;
1860
1861 /* Initialize rec'd sequence number */
1862 if (link->seq == MP_NOSEQ) {
1863 link->seq = (link == link0) ?
1864 MP_INITIAL_SEQ : link0->seq;
1865 }
1866 } else
1867 link->seq = MP_NOSEQ;
1868 }
1869
1870 /* Update MP state as multi-link is active or not */
1871 if (priv->conf.enableMultilink && priv->numActiveLinks > 0)
1872 ng_ppp_start_frag_timer(node);
1873 else {
1874 ng_ppp_stop_frag_timer(node);
1875 ng_ppp_frag_reset(node);
1876 priv->xseq = MP_INITIAL_SEQ;
1877 priv->mseq = MP_INITIAL_SEQ;
1878 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1879 struct ng_ppp_link *const link = &priv->links[i];
1880
1881 bzero(&link->lastWrite, sizeof(link->lastWrite));
1882 link->bytesInQueue = 0;
1883 link->seq = MP_NOSEQ;
1884 }
1885 }
1886 }
1887
1888 /*
1889 * Determine if a new configuration would represent a valid change
1890 * from the current configuration and link activity status.
1891 */
1892 static int
1893 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf)
1894 {
1895 const priv_p priv = node->private;
1896 int i, newNumLinksActive;
1897
1898 /* Check per-link config and count how many links would be active */
1899 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) {
1900 if (newConf->links[i].enableLink && priv->links[i].hook != NULL)
1901 newNumLinksActive++;
1902 if (!newConf->links[i].enableLink)
1903 continue;
1904 if (newConf->links[i].mru < MP_MIN_LINK_MRU)
1905 return (0);
1906 if (newConf->links[i].bandwidth == 0)
1907 return (0);
1908 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH)
1909 return (0);
1910 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY)
1911 return (0);
1912 }
1913
1914 /* Check bundle parameters */
1915 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU)
1916 return (0);
1917
1918 /* Disallow changes to multi-link configuration while MP is active */
1919 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) {
1920 if (!priv->conf.enableMultilink
1921 != !newConf->bund.enableMultilink
1922 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq
1923 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq)
1924 return (0);
1925 }
1926
1927 /* At most one link can be active unless multi-link is enabled */
1928 if (!newConf->bund.enableMultilink && newNumLinksActive > 1)
1929 return (0);
1930
1931 /* Configuration change would be valid */
1932 return (1);
1933 }
1934
1935 /*
1936 * Free all entries in the fragment queue
1937 */
1938 static void
1939 ng_ppp_frag_reset(node_p node)
1940 {
1941 const priv_p priv = node->private;
1942 struct ng_ppp_frag *qent, *qnext;
1943
1944 for (qent = CIRCLEQ_FIRST(&priv->frags);
1945 qent != (void *)&priv->frags; qent = qnext) {
1946 qnext = CIRCLEQ_NEXT(qent, f_qent);
1947 NG_FREE_DATA(qent->data, qent->meta);
1948 FREE(qent, M_NETGRAPH);
1949 }
1950 CIRCLEQ_INIT(&priv->frags);
1951 priv->qlen = 0;
1952 }
1953
1954 /*
1955 * Start fragment queue timer
1956 */
1957 static void
1958 ng_ppp_start_frag_timer(node_p node)
1959 {
1960 const priv_p priv = node->private;
1961
1962 if (!priv->timerActive) {
1963 priv->fragTimer = timeout(ng_ppp_frag_timeout,
1964 node, MP_FRAGTIMER_INTERVAL);
1965 priv->timerActive = 1;
1966 node->refs++;
1967 }
1968 }
1969
1970 /*
1971 * Stop fragment queue timer
1972 */
1973 static void
1974 ng_ppp_stop_frag_timer(node_p node)
1975 {
1976 const priv_p priv = node->private;
1977
1978 if (priv->timerActive) {
1979 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer);
1980 priv->timerActive = 0;
1981 KASSERT(node->refs > 1,
1982 ("%s: refs=%d", __FUNCTION__, node->refs));
1983 ng_unref(node);
1984 }
1985 }
1986
Cache object: 4f59ca83a8eac0efc6e6b1f396dbbb02
|