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HAMMER Utilities: Remove time/transaction-id conversion directives.
[dragonfly.git] / sys / netgraph / ppp / ng_ppp.c
blobe0e30c7aff31b6d1cb51b02d78e31e6cab56fc04
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: src/sys/netgraph/ng_ppp.c,v 1.15.2.10 2003/03/10 17:55:48 archie Exp $
40 * $DragonFly: src/sys/netgraph/ppp/ng_ppp.c,v 1.13 2008/01/05 14:02:39 swildner Exp $
41 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $
42 */
43
44 /*
45 * PPP node type.
46 */
47
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/kernel.h>
51 #include <sys/time.h>
52 #include <sys/mbuf.h>
53 #include <sys/malloc.h>
54 #include <sys/errno.h>
55 #include <sys/ctype.h>
56 #include <sys/thread2.h>
57
58 #include <machine/limits.h>
59
60 #include <netgraph/ng_message.h>
61 #include <netgraph/netgraph.h>
62 #include <netgraph/ng_parse.h>
63 #include "ng_ppp.h"
64 #include <netgraph/vjc/ng_vjc.h>
65
66 #define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
67 #define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
68
69 /* Some PPP protocol numbers we're interested in */
70 #define PROT_APPLETALK 0x0029
71 #define PROT_COMPD 0x00fd
72 #define PROT_CRYPTD 0x0053
73 #define PROT_IP 0x0021
74 #define PROT_IPV6 0x0057
75 #define PROT_IPX 0x002b
76 #define PROT_LCP 0xc021
77 #define PROT_MP 0x003d
78 #define PROT_VJCOMP 0x002d
79 #define PROT_VJUNCOMP 0x002f
80
81 /* Multilink PPP definitions */
82 #define MP_MIN_MRRU 1500 /* per RFC 1990 */
83 #define MP_INITIAL_SEQ 0 /* per RFC 1990 */
84 #define MP_MIN_LINK_MRU 32
85
86 #define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
87 #define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
88 #define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
89 #define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
90
91 #define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
92 #define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
93 #define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
94 #define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
95
96 #define MP_NOSEQ 0x7fffffff /* impossible sequence number */
97
98 /* Sign extension of MP sequence numbers */
99 #define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
100 ((s) | ~MP_SHORT_SEQ_MASK) \
101 : ((s) & MP_SHORT_SEQ_MASK))
102 #define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
103 ((s) | ~MP_LONG_SEQ_MASK) \
104 : ((s) & MP_LONG_SEQ_MASK))
105
106 /* Comparision of MP sequence numbers. Note: all sequence numbers
107 except priv->xseq are stored with the sign bit extended. */
108 #define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y))
109 #define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y))
110
111 #define MP_RECV_SEQ_DIFF(priv,x,y) \
112 ((priv)->conf.recvShortSeq ? \
113 MP_SHORT_SEQ_DIFF((x), (y)) : \
114 MP_LONG_SEQ_DIFF((x), (y)))
115
116 /* Increment receive sequence number */
117 #define MP_NEXT_RECV_SEQ(priv,seq) \
118 ((priv)->conf.recvShortSeq ? \
119 MP_SHORT_EXTEND((seq) + 1) : \
120 MP_LONG_EXTEND((seq) + 1))
121
122 /* Don't fragment transmitted packets smaller than this */
123 #define MP_MIN_FRAG_LEN 6
124
125 /* Maximum fragment reasssembly queue length */
126 #define MP_MAX_QUEUE_LEN 128
127
128 /* Fragment queue scanner period */
129 #define MP_FRAGTIMER_INTERVAL (hz/2)
130
131 /* We store incoming fragments this way */
132 struct ng_ppp_frag {
133 int seq; /* fragment seq# */
134 u_char first; /* First in packet? */
135 u_char last; /* Last in packet? */
136 struct timeval timestamp; /* time of reception */
137 struct mbuf *data; /* Fragment data */
138 meta_p meta; /* Fragment meta */
139 CIRCLEQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
140 };
141
142 /* We use integer indicies to refer to the non-link hooks */
143 static const char *const ng_ppp_hook_names[] = {
144 NG_PPP_HOOK_ATALK,
145 #define HOOK_INDEX_ATALK 0
146 NG_PPP_HOOK_BYPASS,
147 #define HOOK_INDEX_BYPASS 1
148 NG_PPP_HOOK_COMPRESS,
149 #define HOOK_INDEX_COMPRESS 2
150 NG_PPP_HOOK_ENCRYPT,
151 #define HOOK_INDEX_ENCRYPT 3
152 NG_PPP_HOOK_DECOMPRESS,
153 #define HOOK_INDEX_DECOMPRESS 4
154 NG_PPP_HOOK_DECRYPT,
155 #define HOOK_INDEX_DECRYPT 5
156 NG_PPP_HOOK_INET,
157 #define HOOK_INDEX_INET 6
158 NG_PPP_HOOK_IPX,
159 #define HOOK_INDEX_IPX 7
160 NG_PPP_HOOK_VJC_COMP,
161 #define HOOK_INDEX_VJC_COMP 8
162 NG_PPP_HOOK_VJC_IP,
163 #define HOOK_INDEX_VJC_IP 9
164 NG_PPP_HOOK_VJC_UNCOMP,
165 #define HOOK_INDEX_VJC_UNCOMP 10
166 NG_PPP_HOOK_VJC_VJIP,
167 #define HOOK_INDEX_VJC_VJIP 11
168 NG_PPP_HOOK_IPV6,
169 #define HOOK_INDEX_IPV6 12
170 NULL
171 #define HOOK_INDEX_MAX 13
172 };
173
174 /* We store index numbers in the hook private pointer. The HOOK_INDEX()
175 for a hook is either the index (above) for normal hooks, or the ones
176 complement of the link number for link hooks. */
177 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
178
179 /* Per-link private information */
180 struct ng_ppp_link {
181 struct ng_ppp_link_conf conf; /* link configuration */
182 hook_p hook; /* connection to link data */
183 int32_t seq; /* highest rec'd seq# - MSEQ */
184 struct timeval lastWrite; /* time of last write */
185 int bytesInQueue; /* bytes in the output queue */
186 struct ng_ppp_link_stat stats; /* Link stats */
187 };
188
189 /* Total per-node private information */
190 struct ng_ppp_private {
191 struct ng_ppp_bund_conf conf; /* bundle config */
192 struct ng_ppp_link_stat bundleStats; /* bundle stats */
193 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
194 int32_t xseq; /* next out MP seq # */
195 int32_t mseq; /* min links[i].seq */
196 u_char vjCompHooked; /* VJ comp hooked up? */
197 u_char allLinksEqual; /* all xmit the same? */
198 u_char timerActive; /* frag timer active? */
199 u_int numActiveLinks; /* how many links up */
200 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
201 u_int lastLink; /* for round robin */
202 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
203 CIRCLEQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
204 frags;
205 int qlen; /* fraq queue length */
206 struct callout fragTimer; /* fraq queue check */
207 };
208 typedef struct ng_ppp_private *priv_p;
209
210 /* Netgraph node methods */
211 static ng_constructor_t ng_ppp_constructor;
212 static ng_rcvmsg_t ng_ppp_rcvmsg;
213 static ng_shutdown_t ng_ppp_rmnode;
214 static ng_newhook_t ng_ppp_newhook;
215 static ng_rcvdata_t ng_ppp_rcvdata;
216 static ng_disconnect_t ng_ppp_disconnect;
217
218 /* Helper functions */
219 static int ng_ppp_input(node_p node, int bypass,
220 int linkNum, struct mbuf *m, meta_p meta);
221 static int ng_ppp_output(node_p node, int bypass, int proto,
222 int linkNum, struct mbuf *m, meta_p meta);
223 static int ng_ppp_mp_input(node_p node, int linkNum,
224 struct mbuf *m, meta_p meta);
225 static int ng_ppp_check_packet(node_p node);
226 static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
227 static int ng_ppp_frag_process(node_p node);
228 static int ng_ppp_frag_trim(node_p node);
229 static void ng_ppp_frag_timeout(void *arg);
230 static void ng_ppp_frag_checkstale(node_p node);
231 static void ng_ppp_frag_reset(node_p node);
232 static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
233 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
234 static int ng_ppp_intcmp(const void *v1, const void *v2);
235 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
236 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
237 static int ng_ppp_config_valid(node_p node,
238 const struct ng_ppp_node_conf *newConf);
239 static void ng_ppp_update(node_p node, int newConf);
240 static void ng_ppp_start_frag_timer(node_p node);
241 static void ng_ppp_stop_frag_timer(node_p node);
242
243 /* Parse type for struct ng_ppp_mp_state_type */
244 static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = {
245 &ng_parse_hint32_type,
246 NG_PPP_MAX_LINKS
247 };
248 static const struct ng_parse_type ng_ppp_rseq_array_type = {
249 &ng_parse_fixedarray_type,
250 &ng_ppp_rseq_array_info,
251 };
252 static const struct ng_parse_struct_field ng_ppp_mp_state_type_fields[]
253 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type);
254 static const struct ng_parse_type ng_ppp_mp_state_type = {
255 &ng_parse_struct_type,
256 &ng_ppp_mp_state_type_fields
257 };
258
259 /* Parse type for struct ng_ppp_link_conf */
260 static const struct ng_parse_struct_field ng_ppp_link_type_fields[]
261 = NG_PPP_LINK_TYPE_INFO;
262 static const struct ng_parse_type ng_ppp_link_type = {
263 &ng_parse_struct_type,
264 &ng_ppp_link_type_fields
265 };
266
267 /* Parse type for struct ng_ppp_bund_conf */
268 static const struct ng_parse_struct_field ng_ppp_bund_type_fields[]
269 = NG_PPP_BUND_TYPE_INFO;
270 static const struct ng_parse_type ng_ppp_bund_type = {
271 &ng_parse_struct_type,
272 &ng_ppp_bund_type_fields
273 };
274
275 /* Parse type for struct ng_ppp_node_conf */
276 static const struct ng_parse_fixedarray_info ng_ppp_array_info = {
277 &ng_ppp_link_type,
278 NG_PPP_MAX_LINKS
279 };
280 static const struct ng_parse_type ng_ppp_link_array_type = {
281 &ng_parse_fixedarray_type,
282 &ng_ppp_array_info,
283 };
284 static const struct ng_parse_struct_field ng_ppp_conf_type_fields[]
285 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
286 static const struct ng_parse_type ng_ppp_conf_type = {
287 &ng_parse_struct_type,
288 &ng_ppp_conf_type_fields
289 };
290
291 /* Parse type for struct ng_ppp_link_stat */
292 static const struct ng_parse_struct_field ng_ppp_stats_type_fields[]
293 = NG_PPP_STATS_TYPE_INFO;
294 static const struct ng_parse_type ng_ppp_stats_type = {
295 &ng_parse_struct_type,
296 &ng_ppp_stats_type_fields
297 };
298
299 /* List of commands and how to convert arguments to/from ASCII */
300 static const struct ng_cmdlist ng_ppp_cmds[] = {
301 {
302 NGM_PPP_COOKIE,
303 NGM_PPP_SET_CONFIG,
304 "setconfig",
305 &ng_ppp_conf_type,
306 NULL
307 },
308 {
309 NGM_PPP_COOKIE,
310 NGM_PPP_GET_CONFIG,
311 "getconfig",
312 NULL,
313 &ng_ppp_conf_type
314 },
315 {
316 NGM_PPP_COOKIE,
317 NGM_PPP_GET_MP_STATE,
318 "getmpstate",
319 NULL,
320 &ng_ppp_mp_state_type
321 },
322 {
323 NGM_PPP_COOKIE,
324 NGM_PPP_GET_LINK_STATS,
325 "getstats",
326 &ng_parse_int16_type,
327 &ng_ppp_stats_type
328 },
329 {
330 NGM_PPP_COOKIE,
331 NGM_PPP_CLR_LINK_STATS,
332 "clrstats",
333 &ng_parse_int16_type,
334 NULL
335 },
336 {
337 NGM_PPP_COOKIE,
338 NGM_PPP_GETCLR_LINK_STATS,
339 "getclrstats",
340 &ng_parse_int16_type,
341 &ng_ppp_stats_type
342 },
343 { 0 }
344 };
345
346 /* Node type descriptor */
347 static struct ng_type ng_ppp_typestruct = {
348 NG_VERSION,
349 NG_PPP_NODE_TYPE,
350 NULL,
351 ng_ppp_constructor,
352 ng_ppp_rcvmsg,
353 ng_ppp_rmnode,
354 ng_ppp_newhook,
355 NULL,
356 NULL,
357 ng_ppp_rcvdata,
358 ng_ppp_rcvdata,
359 ng_ppp_disconnect,
360 ng_ppp_cmds
361 };
362 NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
363
364 static int *compareLatencies; /* hack for ng_ppp_intcmp() */
365
366 /* Address and control field header */
367 static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
368
369 /* Maximum time we'll let a complete incoming packet sit in the queue */
370 static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
371
372 #define ERROUT(x) do { error = (x); goto done; } while (0)
373
374 /************************************************************************
375 NETGRAPH NODE STUFF
376 ************************************************************************/
377
378 /*
379 * Node type constructor
380 */
381 static int
382 ng_ppp_constructor(node_p *nodep)
383 {
384 priv_p priv;
385 int i, error;
386
387 /* Allocate private structure */
388 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
389 if (priv == NULL)
390 return (ENOMEM);
391
392 /* Call generic node constructor */
393 if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) {
394 FREE(priv, M_NETGRAPH);
395 return (error);
396 }
397 (*nodep)->private = priv;
398
399 /* Initialize state */
400 CIRCLEQ_INIT(&priv->frags);
401 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
402 priv->links[i].seq = MP_NOSEQ;
403 callout_init(&priv->fragTimer);
404
405 /* Done */
406 return (0);
407 }
408
409 /*
410 * Give our OK for a hook to be added
411 */
412 static int
413 ng_ppp_newhook(node_p node, hook_p hook, const char *name)
414 {
415 const priv_p priv = node->private;
416 int linkNum = -1;
417 hook_p *hookPtr = NULL;
418 int hookIndex = -1;
419
420 /* Figure out which hook it is */
421 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
422 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
423 const char *cp;
424 char *eptr;
425
426 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
427 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
428 return (EINVAL);
429 linkNum = (int)strtoul(cp, &eptr, 10);
430 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
431 return (EINVAL);
432 hookPtr = &priv->links[linkNum].hook;
433 hookIndex = ~linkNum;
434 } else { /* must be a non-link hook */
435 int i;
436
437 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
438 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
439 hookPtr = &priv->hooks[i];
440 hookIndex = i;
441 break;
442 }
443 }
444 if (ng_ppp_hook_names[i] == NULL)
445 return (EINVAL); /* no such hook */
446 }
447
448 /* See if hook is already connected */
449 if (*hookPtr != NULL)
450 return (EISCONN);
451
452 /* Disallow more than one link unless multilink is enabled */
453 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
454 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
455 return (ENODEV);
456
457 /* OK */
458 *hookPtr = hook;
459 HOOK_INDEX(hook) = hookIndex;
460 ng_ppp_update(node, 0);
461 return (0);
462 }
463
464 /*
465 * Receive a control message
466 */
467 static int
468 ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg,
469 const char *raddr, struct ng_mesg **rptr)
470 {
471 const priv_p priv = node->private;
472 struct ng_mesg *resp = NULL;
473 int error = 0;
474
475 switch (msg->header.typecookie) {
476 case NGM_PPP_COOKIE:
477 switch (msg->header.cmd) {
478 case NGM_PPP_SET_CONFIG:
479 {
480 struct ng_ppp_node_conf *const conf =
481 (struct ng_ppp_node_conf *)msg->data;
482 int i;
483
484 /* Check for invalid or illegal config */
485 if (msg->header.arglen != sizeof(*conf))
486 ERROUT(EINVAL);
487 if (!ng_ppp_config_valid(node, conf))
488 ERROUT(EINVAL);
489
490 /* Copy config */
491 priv->conf = conf->bund;
492 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
493 priv->links[i].conf = conf->links[i];
494 ng_ppp_update(node, 1);
495 break;
496 }
497 case NGM_PPP_GET_CONFIG:
498 {
499 struct ng_ppp_node_conf *conf;
500 int i;
501
502 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
503 if (resp == NULL)
504 ERROUT(ENOMEM);
505 conf = (struct ng_ppp_node_conf *)resp->data;
506 conf->bund = priv->conf;
507 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
508 conf->links[i] = priv->links[i].conf;
509 break;
510 }
511 case NGM_PPP_GET_MP_STATE:
512 {
513 struct ng_ppp_mp_state *info;
514 int i;
515
516 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT);
517 if (resp == NULL)
518 ERROUT(ENOMEM);
519 info = (struct ng_ppp_mp_state *)resp->data;
520 bzero(info, sizeof(*info));
521 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
522 if (priv->links[i].seq != MP_NOSEQ)
523 info->rseq[i] = priv->links[i].seq;
524 }
525 info->mseq = priv->mseq;
526 info->xseq = priv->xseq;
527 break;
528 }
529 case NGM_PPP_GET_LINK_STATS:
530 case NGM_PPP_CLR_LINK_STATS:
531 case NGM_PPP_GETCLR_LINK_STATS:
532 {
533 struct ng_ppp_link_stat *stats;
534 u_int16_t linkNum;
535
536 if (msg->header.arglen != sizeof(u_int16_t))
537 ERROUT(EINVAL);
538 linkNum = *((u_int16_t *) msg->data);
539 if (linkNum >= NG_PPP_MAX_LINKS
540 && linkNum != NG_PPP_BUNDLE_LINKNUM)
541 ERROUT(EINVAL);
542 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ?
543 &priv->bundleStats : &priv->links[linkNum].stats;
544 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) {
545 NG_MKRESPONSE(resp, msg,
546 sizeof(struct ng_ppp_link_stat), M_NOWAIT);
547 if (resp == NULL)
548 ERROUT(ENOMEM);
549 bcopy(stats, resp->data, sizeof(*stats));
550 }
551 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS)
552 bzero(stats, sizeof(*stats));
553 break;
554 }
555 default:
556 error = EINVAL;
557 break;
558 }
559 break;
560 case NGM_VJC_COOKIE:
561 {
562 char path[NG_PATHSIZ];
563 node_p origNode;
564
565 if ((error = ng_path2node(node, raddr, &origNode, NULL)) != 0)
566 ERROUT(error);
567 ksnprintf(path, sizeof(path), "[%lx]:%s",
568 (long)node, NG_PPP_HOOK_VJC_IP);
569 return ng_send_msg(origNode, msg, path, rptr);
570 }
571 default:
572 error = EINVAL;
573 break;
574 }
575 if (rptr)
576 *rptr = resp;
577 else if (resp)
578 FREE(resp, M_NETGRAPH);
579
580 done:
581 FREE(msg, M_NETGRAPH);
582 return (error);
583 }
584
585 /*
586 * Receive data on a hook
587 */
588 static int
589 ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
590 {
591 const node_p node = hook->node;
592 const priv_p priv = node->private;
593 const int index = HOOK_INDEX(hook);
594 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
595 hook_p outHook = NULL;
596 int proto = 0, error;
597
598 /* Did it come from a link hook? */
599 if (index < 0) {
600 struct ng_ppp_link *link;
601
602 /* Convert index into a link number */
603 linkNum = (u_int16_t)~index;
604 KASSERT(linkNum < NG_PPP_MAX_LINKS,
605 ("%s: bogus index 0x%x", __func__, index));
606 link = &priv->links[linkNum];
607
608 /* Stats */
609 link->stats.recvFrames++;
610 link->stats.recvOctets += m->m_pkthdr.len;
611
612 /* Strip address and control fields, if present */
613 if (m->m_pkthdr.len >= 2) {
614 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
615 NG_FREE_DATA(m, meta);
616 return (ENOBUFS);
617 }
618 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
619 m_adj(m, 2);
620 }
621
622 /* Dispatch incoming frame (if not enabled, to bypass) */
623 return ng_ppp_input(node,
624 !link->conf.enableLink, linkNum, m, meta);
625 }
626
627 /* Get protocol & check if data allowed from this hook */
628 switch (index) {
629
630 /* Outgoing data */
631 case HOOK_INDEX_ATALK:
632 if (!priv->conf.enableAtalk) {
633 NG_FREE_DATA(m, meta);
634 return (ENXIO);
635 }
636 proto = PROT_APPLETALK;
637 break;
638 case HOOK_INDEX_IPX:
639 if (!priv->conf.enableIPX) {
640 NG_FREE_DATA(m, meta);
641 return (ENXIO);
642 }
643 proto = PROT_IPX;
644 break;
645 case HOOK_INDEX_IPV6:
646 if (!priv->conf.enableIPv6) {
647 NG_FREE_DATA(m, meta);
648 return (ENXIO);
649 }
650 proto = PROT_IPV6;
651 break;
652 case HOOK_INDEX_INET:
653 case HOOK_INDEX_VJC_VJIP:
654 if (!priv->conf.enableIP) {
655 NG_FREE_DATA(m, meta);
656 return (ENXIO);
657 }
658 proto = PROT_IP;
659 break;
660 case HOOK_INDEX_VJC_COMP:
661 if (!priv->conf.enableVJCompression) {
662 NG_FREE_DATA(m, meta);
663 return (ENXIO);
664 }
665 proto = PROT_VJCOMP;
666 break;
667 case HOOK_INDEX_VJC_UNCOMP:
668 if (!priv->conf.enableVJCompression) {
669 NG_FREE_DATA(m, meta);
670 return (ENXIO);
671 }
672 proto = PROT_VJUNCOMP;
673 break;
674 case HOOK_INDEX_COMPRESS:
675 if (!priv->conf.enableCompression) {
676 NG_FREE_DATA(m, meta);
677 return (ENXIO);
678 }
679 proto = PROT_COMPD;
680 break;
681 case HOOK_INDEX_ENCRYPT:
682 if (!priv->conf.enableEncryption) {
683 NG_FREE_DATA(m, meta);
684 return (ENXIO);
685 }
686 proto = PROT_CRYPTD;
687 break;
688 case HOOK_INDEX_BYPASS:
689 if (m->m_pkthdr.len < 4) {
690 NG_FREE_DATA(m, meta);
691 return (EINVAL);
692 }
693 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
694 NG_FREE_META(meta);
695 return (ENOBUFS);
696 }
697 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
698 proto = ntohs(mtod(m, u_int16_t *)[1]);
699 m_adj(m, 4);
700 if (linkNum >= NG_PPP_MAX_LINKS
701 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
702 NG_FREE_DATA(m, meta);
703 return (EINVAL);
704 }
705 break;
706
707 /* Incoming data */
708 case HOOK_INDEX_VJC_IP:
709 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
710 NG_FREE_DATA(m, meta);
711 return (ENXIO);
712 }
713 break;
714 case HOOK_INDEX_DECOMPRESS:
715 if (!priv->conf.enableDecompression) {
716 NG_FREE_DATA(m, meta);
717 return (ENXIO);
718 }
719 break;
720 case HOOK_INDEX_DECRYPT:
721 if (!priv->conf.enableDecryption) {
722 NG_FREE_DATA(m, meta);
723 return (ENXIO);
724 }
725 break;
726 default:
727 panic("%s: bogus index 0x%x", __func__, index);
728 }
729
730 /* Now figure out what to do with the frame */
731 switch (index) {
732
733 /* Outgoing data */
734 case HOOK_INDEX_INET:
735 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
736 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
737 break;
738 }
739 /* FALLTHROUGH */
740 case HOOK_INDEX_ATALK:
741 case HOOK_INDEX_IPV6:
742 case HOOK_INDEX_IPX:
743 case HOOK_INDEX_VJC_COMP:
744 case HOOK_INDEX_VJC_UNCOMP:
745 case HOOK_INDEX_VJC_VJIP:
746 if (priv->conf.enableCompression
747 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
748 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
749 NG_FREE_META(meta);
750 return (ENOBUFS);
751 }
752 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
753 break;
754 }
755 /* FALLTHROUGH */
756 case HOOK_INDEX_COMPRESS:
757 if (priv->conf.enableEncryption
758 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
759 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
760 NG_FREE_META(meta);
761 return (ENOBUFS);
762 }
763 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
764 break;
765 }
766 /* FALLTHROUGH */
767 case HOOK_INDEX_ENCRYPT:
768 return ng_ppp_output(node, 0,
769 proto, NG_PPP_BUNDLE_LINKNUM, m, meta);
770
771 case HOOK_INDEX_BYPASS:
772 return ng_ppp_output(node, 1, proto, linkNum, m, meta);
773
774 /* Incoming data */
775 case HOOK_INDEX_DECRYPT:
776 case HOOK_INDEX_DECOMPRESS:
777 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
778
779 case HOOK_INDEX_VJC_IP:
780 outHook = priv->hooks[HOOK_INDEX_INET];
781 break;
782 }
783
784 /* Send packet out hook */
785 NG_SEND_DATA(error, outHook, m, meta);
786 return (error);
787 }
788
789 /*
790 * Destroy node
791 */
792 static int
793 ng_ppp_rmnode(node_p node)
794 {
795 const priv_p priv = node->private;
796
797 /* Stop fragment queue timer */
798 ng_ppp_stop_frag_timer(node);
799
800 /* Take down netgraph node */
801 node->flags |= NG_INVALID;
802 ng_cutlinks(node);
803 ng_unname(node);
804 ng_ppp_frag_reset(node);
805 bzero(priv, sizeof(*priv));
806 FREE(priv, M_NETGRAPH);
807 node->private = NULL;
808 ng_unref(node); /* let the node escape */
809 return (0);
810 }
811
812 /*
813 * Hook disconnection
814 */
815 static int
816 ng_ppp_disconnect(hook_p hook)
817 {
818 const node_p node = hook->node;
819 const priv_p priv = node->private;
820 const int index = HOOK_INDEX(hook);
821
822 /* Zero out hook pointer */
823 if (index < 0)
824 priv->links[~index].hook = NULL;
825 else
826 priv->hooks[index] = NULL;
827
828 /* Update derived info (or go away if no hooks left) */
829 if (node->numhooks > 0)
830 ng_ppp_update(node, 0);
831 else
832 ng_rmnode(node);
833 return (0);
834 }
835
836 /************************************************************************
837 HELPER STUFF
838 ************************************************************************/
839
840 /*
841 * Handle an incoming frame. Extract the PPP protocol number
842 * and dispatch accordingly.
843 */
844 static int
845 ng_ppp_input(node_p node, int bypass, int linkNum, struct mbuf *m, meta_p meta)
846 {
847 const priv_p priv = node->private;
848 hook_p outHook = NULL;
849 int proto, error;
850
851 /* Extract protocol number */
852 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
853 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
854 NG_FREE_META(meta);
855 return (ENOBUFS);
856 }
857 proto = (proto << 8) + *mtod(m, u_char *);
858 m_adj(m, 1);
859 }
860 if (!PROT_VALID(proto)) {
861 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
862 priv->bundleStats.badProtos++;
863 else
864 priv->links[linkNum].stats.badProtos++;
865 NG_FREE_DATA(m, meta);
866 return (EINVAL);
867 }
868
869 /* Bypass frame? */
870 if (bypass)
871 goto bypass;
872
873 /* Check protocol */
874 switch (proto) {
875 case PROT_COMPD:
876 if (priv->conf.enableDecompression)
877 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
878 break;
879 case PROT_CRYPTD:
880 if (priv->conf.enableDecryption)
881 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
882 break;
883 case PROT_VJCOMP:
884 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
885 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
886 break;
887 case PROT_VJUNCOMP:
888 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
889 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
890 break;
891 case PROT_MP:
892 if (priv->conf.enableMultilink
893 && linkNum != NG_PPP_BUNDLE_LINKNUM)
894 return ng_ppp_mp_input(node, linkNum, m, meta);
895 break;
896 case PROT_APPLETALK:
897 if (priv->conf.enableAtalk)
898 outHook = priv->hooks[HOOK_INDEX_ATALK];
899 break;
900 case PROT_IPX:
901 if (priv->conf.enableIPX)
902 outHook = priv->hooks[HOOK_INDEX_IPX];
903 break;
904 case PROT_IP:
905 if (priv->conf.enableIP)
906 outHook = priv->hooks[HOOK_INDEX_INET];
907 break;
908 case PROT_IPV6:
909 if (priv->conf.enableIPv6)
910 outHook = priv->hooks[HOOK_INDEX_IPV6];
911 break;
912 }
913
914 bypass:
915 /* For unknown/inactive protocols, forward out the bypass hook */
916 if (outHook == NULL) {
917 u_int16_t hdr[2];
918
919 hdr[0] = htons(linkNum);
920 hdr[1] = htons((u_int16_t)proto);
921 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
922 NG_FREE_META(meta);
923 return (ENOBUFS);
924 }
925 outHook = priv->hooks[HOOK_INDEX_BYPASS];
926 }
927
928 /* Forward frame */
929 NG_SEND_DATA(error, outHook, m, meta);
930 return (error);
931 }
932
933 /*
934 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM.
935 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
936 *
937 * If the frame is too big for the particular link, return EMSGSIZE.
938 */
939 static int
940 ng_ppp_output(node_p node, int bypass,
941 int proto, int linkNum, struct mbuf *m, meta_p meta)
942 {
943 const priv_p priv = node->private;
944 struct ng_ppp_link *link;
945 int len, error;
946 u_int16_t mru;
947
948 /* If not doing MP, map bundle virtual link to (the only) link */
949 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
950 linkNum = priv->activeLinks[0];
951
952 /* Get link pointer (optimization) */
953 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
954 &priv->links[linkNum] : NULL;
955
956 /* Check link status (if real) */
957 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
958 if (!bypass && !link->conf.enableLink) {
959 NG_FREE_DATA(m, meta);
960 return (ENXIO);
961 }
962 if (link->hook == NULL) {
963 NG_FREE_DATA(m, meta);
964 return (ENETDOWN);
965 }
966 }
967
968 /* Check peer's MRU for this link */
969 mru = (link != NULL) ? link->conf.mru : priv->conf.mrru;
970 if (mru != 0 && m->m_pkthdr.len > mru) {
971 NG_FREE_DATA(m, meta);
972 return (EMSGSIZE);
973 }
974
975 /* Prepend protocol number, possibly compressed */
976 if ((m = ng_ppp_addproto(m, proto,
977 linkNum == NG_PPP_BUNDLE_LINKNUM
978 || link->conf.enableProtoComp)) == NULL) {
979 NG_FREE_META(meta);
980 return (ENOBUFS);
981 }
982
983 /* Special handling for the MP virtual link */
984 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
985 return ng_ppp_mp_output(node, m, meta);
986
987 /* Prepend address and control field (unless compressed) */
988 if (proto == PROT_LCP || !link->conf.enableACFComp) {
989 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
990 NG_FREE_META(meta);
991 return (ENOBUFS);
992 }
993 }
994
995 /* Deliver frame */
996 len = m->m_pkthdr.len;
997 NG_SEND_DATA(error, link->hook, m, meta);
998
999 /* Update stats and 'bytes in queue' counter */
1000 if (error == 0) {
1001 link->stats.xmitFrames++;
1002 link->stats.xmitOctets += len;
1003 link->bytesInQueue += len;
1004 getmicrouptime(&link->lastWrite);
1005 }
1006 return error;
1007 }
1008
1009 /*
1010 * Handle an incoming multi-link fragment
1011 *
1012 * The fragment reassembly algorithm is somewhat complex. This is mainly
1013 * because we are required not to reorder the reconstructed packets, yet
1014 * fragments are only guaranteed to arrive in order on a per-link basis.
1015 * In other words, when we have a complete packet ready, but the previous
1016 * packet is still incomplete, we have to decide between delivering the
1017 * complete packet and throwing away the incomplete one, or waiting to
1018 * see if the remainder of the incomplete one arrives, at which time we
1019 * can deliver both packets, in order.
1020 *
1021 * This problem is exacerbated by "sequence number slew", which is when
1022 * the sequence numbers coming in from different links are far apart from
1023 * each other. In particular, certain unnamed equipment (*cough* Ascend)
1024 * has been seen to generate sequence number slew of up to 10 on an ISDN
1025 * 2B-channel MP link. There is nothing invalid about sequence number slew
1026 * but it makes the reasssembly process have to work harder.
1027 *
1028 * However, the peer is required to transmit fragments in order on each
1029 * link. That means if we define MSEQ as the minimum over all links of
1030 * the highest sequence number received on that link, then we can always
1031 * give up any hope of receiving a fragment with sequence number < MSEQ in
1032 * the future (all of this using 'wraparound' sequence number space).
1033 * Therefore we can always immediately throw away incomplete packets
1034 * missing fragments with sequence numbers < MSEQ.
1035 *
1036 * Here is an overview of our algorithm:
1037 *
1038 * o Received fragments are inserted into a queue, for which we
1039 * maintain these invariants between calls to this function:
1040 *
1041 * - Fragments are ordered in the queue by sequence number
1042 * - If a complete packet is at the head of the queue, then
1043 * the first fragment in the packet has seq# > MSEQ + 1
1044 * (otherwise, we could deliver it immediately)
1045 * - If any fragments have seq# < MSEQ, then they are necessarily
1046 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
1047 * we can throw them away because they'll never be completed)
1048 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
1049 *
1050 * o We have a periodic timer that checks the queue for the first
1051 * complete packet that has been sitting in the queue "too long".
1052 * When one is detected, all previous (incomplete) fragments are
1053 * discarded, their missing fragments are declared lost and MSEQ
1054 * is increased.
1055 *
1056 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1057 * because we've already delcared it lost.
1058 *
1059 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1060 */
1061 static int
1062 ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
1063 {
1064 const priv_p priv = node->private;
1065 struct ng_ppp_link *const link = &priv->links[linkNum];
1066 struct ng_ppp_frag frag0, *frag = &frag0;
1067 struct ng_ppp_frag *qent;
1068 int i, diff, inserted;
1069
1070 /* Stats */
1071 priv->bundleStats.recvFrames++;
1072 priv->bundleStats.recvOctets += m->m_pkthdr.len;
1073
1074 /* Extract fragment information from MP header */
1075 if (priv->conf.recvShortSeq) {
1076 u_int16_t shdr;
1077
1078 if (m->m_pkthdr.len < 2) {
1079 link->stats.runts++;
1080 NG_FREE_DATA(m, meta);
1081 return (EINVAL);
1082 }
1083 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1084 NG_FREE_META(meta);
1085 return (ENOBUFS);
1086 }
1087 shdr = ntohs(*mtod(m, u_int16_t *));
1088 frag->seq = MP_SHORT_EXTEND(shdr);
1089 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1090 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1091 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1092 m_adj(m, 2);
1093 } else {
1094 u_int32_t lhdr;
1095
1096 if (m->m_pkthdr.len < 4) {
1097 link->stats.runts++;
1098 NG_FREE_DATA(m, meta);
1099 return (EINVAL);
1100 }
1101 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1102 NG_FREE_META(meta);
1103 return (ENOBUFS);
1104 }
1105 lhdr = ntohl(*mtod(m, u_int32_t *));
1106 frag->seq = MP_LONG_EXTEND(lhdr);
1107 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1108 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1109 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1110 m_adj(m, 4);
1111 }
1112 frag->data = m;
1113 frag->meta = meta;
1114 getmicrouptime(&frag->timestamp);
1115
1116 /* If sequence number is < MSEQ, we've already declared this
1117 fragment as lost, so we have no choice now but to drop it */
1118 if (diff < 0) {
1119 link->stats.dropFragments++;
1120 NG_FREE_DATA(m, meta);
1121 return (0);
1122 }
1123
1124 /* Update highest received sequence number on this link and MSEQ */
1125 priv->mseq = link->seq = frag->seq;
1126 for (i = 0; i < priv->numActiveLinks; i++) {
1127 struct ng_ppp_link *const alink =
1128 &priv->links[priv->activeLinks[i]];
1129
1130 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1131 priv->mseq = alink->seq;
1132 }
1133
1134 /* Allocate a new frag struct for the queue */
1135 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT);
1136 if (frag == NULL) {
1137 NG_FREE_DATA(m, meta);
1138 ng_ppp_frag_process(node);
1139 return (ENOMEM);
1140 }
1141 *frag = frag0;
1142
1143 /* Add fragment to queue, which is sorted by sequence number */
1144 inserted = 0;
1145 CIRCLEQ_FOREACH_REVERSE(qent, &priv->frags, f_qent) {
1146 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq);
1147 if (diff > 0) {
1148 CIRCLEQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1149 inserted = 1;
1150 break;
1151 } else if (diff == 0) { /* should never happen! */
1152 link->stats.dupFragments++;
1153 NG_FREE_DATA(frag->data, frag->meta);
1154 FREE(frag, M_NETGRAPH);
1155 return (EINVAL);
1156 }
1157 }
1158 if (!inserted)
1159 CIRCLEQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1160 priv->qlen++;
1161
1162 /* Process the queue */
1163 return ng_ppp_frag_process(node);
1164 }
1165
1166 /*
1167 * Examine our list of fragments, and determine if there is a
1168 * complete and deliverable packet at the head of the list.
1169 * Return 1 if so, zero otherwise.
1170 */
1171 static int
1172 ng_ppp_check_packet(node_p node)
1173 {
1174 const priv_p priv = node->private;
1175 struct ng_ppp_frag *qent, *qnext;
1176
1177 /* Check for empty queue */
1178 if (CIRCLEQ_EMPTY(&priv->frags))
1179 return (0);
1180
1181 /* Check first fragment is the start of a deliverable packet */
1182 qent = CIRCLEQ_FIRST(&priv->frags);
1183 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1184 return (0);
1185
1186 /* Check that all the fragments are there */
1187 while (!qent->last) {
1188 qnext = CIRCLEQ_NEXT(qent, f_qent);
1189 if (qnext == (void *)&priv->frags) /* end of queue */
1190 return (0);
1191 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq))
1192 return (0);
1193 qent = qnext;
1194 }
1195
1196 /* Got one */
1197 return (1);
1198 }
1199
1200 /*
1201 * Pull a completed packet off the head of the incoming fragment queue.
1202 * This assumes there is a completed packet there to pull off.
1203 */
1204 static void
1205 ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1206 {
1207 const priv_p priv = node->private;
1208 struct ng_ppp_frag *qent, *qnext;
1209 struct mbuf *m = NULL, *tail;
1210
1211 qent = CIRCLEQ_FIRST(&priv->frags);
1212 KASSERT(!CIRCLEQ_EMPTY(&priv->frags) && qent->first,
1213 ("%s: no packet", __func__));
1214 for (tail = NULL; qent != NULL; qent = qnext) {
1215 qnext = CIRCLEQ_NEXT(qent, f_qent);
1216 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1217 ("%s: empty q", __func__));
1218 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1219 if (tail == NULL) {
1220 tail = m = qent->data;
1221 *metap = qent->meta; /* inherit first frag's meta */
1222 } else {
1223 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1224 tail->m_next = qent->data;
1225 NG_FREE_META(qent->meta); /* drop other frags' metas */
1226 }
1227 while (tail->m_next != NULL)
1228 tail = tail->m_next;
1229 if (qent->last)
1230 qnext = NULL;
1231 FREE(qent, M_NETGRAPH);
1232 priv->qlen--;
1233 }
1234 *mp = m;
1235 }
1236
1237 /*
1238 * Trim fragments from the queue whose packets can never be completed.
1239 * This assumes a complete packet is NOT at the beginning of the queue.
1240 * Returns 1 if fragments were removed, zero otherwise.
1241 */
1242 static int
1243 ng_ppp_frag_trim(node_p node)
1244 {
1245 const priv_p priv = node->private;
1246 struct ng_ppp_frag *qent, *qnext = NULL;
1247 int removed = 0;
1248
1249 /* Scan for "dead" fragments and remove them */
1250 while (1) {
1251 int dead = 0;
1252
1253 /* If queue is empty, we're done */
1254 if (CIRCLEQ_EMPTY(&priv->frags))
1255 break;
1256
1257 /* Determine whether first fragment can ever be completed */
1258 CIRCLEQ_FOREACH(qent, &priv->frags, f_qent) {
1259 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1260 break;
1261 qnext = CIRCLEQ_NEXT(qent, f_qent);
1262 KASSERT(qnext != (void*)&priv->frags,
1263 ("%s: last frag < MSEQ?", __func__));
1264 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)
1265 || qent->last || qnext->first) {
1266 dead = 1;
1267 break;
1268 }
1269 }
1270 if (!dead)
1271 break;
1272
1273 /* Remove fragment and all others in the same packet */
1274 while ((qent = CIRCLEQ_FIRST(&priv->frags)) != qnext) {
1275 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1276 ("%s: empty q", __func__));
1277 priv->bundleStats.dropFragments++;
1278 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1279 NG_FREE_DATA(qent->data, qent->meta);
1280 FREE(qent, M_NETGRAPH);
1281 priv->qlen--;
1282 removed = 1;
1283 }
1284 }
1285 return (removed);
1286 }
1287
1288 /*
1289 * Run the queue, restoring the queue invariants
1290 */
1291 static int
1292 ng_ppp_frag_process(node_p node)
1293 {
1294 const priv_p priv = node->private;
1295 struct mbuf *m;
1296 meta_p meta;
1297
1298 /* Deliver any deliverable packets */
1299 while (ng_ppp_check_packet(node)) {
1300 ng_ppp_get_packet(node, &m, &meta);
1301 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1302 }
1303
1304 /* Delete dead fragments and try again */
1305 if (ng_ppp_frag_trim(node)) {
1306 while (ng_ppp_check_packet(node)) {
1307 ng_ppp_get_packet(node, &m, &meta);
1308 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1309 }
1310 }
1311
1312 /* Check for stale fragments while we're here */
1313 ng_ppp_frag_checkstale(node);
1314
1315 /* Check queue length */
1316 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1317 struct ng_ppp_frag *qent;
1318 int i;
1319
1320 /* Get oldest fragment */
1321 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1322 ("%s: empty q", __func__));
1323 qent = CIRCLEQ_FIRST(&priv->frags);
1324
1325 /* Bump MSEQ if necessary */
1326 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1327 priv->mseq = qent->seq;
1328 for (i = 0; i < priv->numActiveLinks; i++) {
1329 struct ng_ppp_link *const alink =
1330 &priv->links[priv->activeLinks[i]];
1331
1332 if (MP_RECV_SEQ_DIFF(priv,
1333 alink->seq, priv->mseq) < 0)
1334 alink->seq = priv->mseq;
1335 }
1336 }
1337
1338 /* Drop it */
1339 priv->bundleStats.dropFragments++;
1340 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1341 NG_FREE_DATA(qent->data, qent->meta);
1342 FREE(qent, M_NETGRAPH);
1343 priv->qlen--;
1344
1345 /* Process queue again */
1346 return ng_ppp_frag_process(node);
1347 }
1348
1349 /* Done */
1350 return (0);
1351 }
1352
1353 /*
1354 * Check for 'stale' completed packets that need to be delivered
1355 *
1356 * If a link goes down or has a temporary failure, MSEQ can get
1357 * "stuck", because no new incoming fragments appear on that link.
1358 * This can cause completed packets to never get delivered if
1359 * their sequence numbers are all > MSEQ + 1.
1360 *
1361 * This routine checks how long all of the completed packets have
1362 * been sitting in the queue, and if too long, removes fragments
1363 * from the queue and increments MSEQ to allow them to be delivered.
1364 */
1365 static void
1366 ng_ppp_frag_checkstale(node_p node)
1367 {
1368 const priv_p priv = node->private;
1369 struct ng_ppp_frag *qent, *beg, *end;
1370 struct timeval now, age;
1371 struct mbuf *m;
1372 meta_p meta;
1373 int i, seq;
1374 int endseq;
1375
1376 now.tv_sec = 0; /* uninitialized state */
1377 while (1) {
1378
1379 /* If queue is empty, we're done */
1380 if (CIRCLEQ_EMPTY(&priv->frags))
1381 break;
1382
1383 /* Find the first complete packet in the queue */
1384 beg = end = NULL;
1385 seq = CIRCLEQ_FIRST(&priv->frags)->seq;
1386 CIRCLEQ_FOREACH(qent, &priv->frags, f_qent) {
1387 if (qent->first)
1388 beg = qent;
1389 else if (qent->seq != seq)
1390 beg = NULL;
1391 if (beg != NULL && qent->last) {
1392 end = qent;
1393 break;
1394 }
1395 seq = MP_NEXT_RECV_SEQ(priv, seq);
1396 }
1397
1398 /* If none found, exit */
1399 if (end == NULL)
1400 break;
1401
1402 /* Get current time (we assume we've been up for >= 1 second) */
1403 if (now.tv_sec == 0)
1404 getmicrouptime(&now);
1405
1406 /* Check if packet has been queued too long */
1407 age = now;
1408 timevalsub(&age, &beg->timestamp);
1409 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1410 break;
1411
1412 /* Throw away junk fragments in front of the completed packet */
1413 while ((qent = CIRCLEQ_FIRST(&priv->frags)) != beg) {
1414 KASSERT(!CIRCLEQ_EMPTY(&priv->frags),
1415 ("%s: empty q", __func__));
1416 priv->bundleStats.dropFragments++;
1417 CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
1418 NG_FREE_DATA(qent->data, qent->meta);
1419 FREE(qent, M_NETGRAPH);
1420 priv->qlen--;
1421 }
1422
1423 /* Extract completed packet */
1424 endseq = end->seq;
1425 ng_ppp_get_packet(node, &m, &meta);
1426
1427 /* Bump MSEQ if necessary */
1428 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, endseq) < 0) {
1429 priv->mseq = endseq;
1430 for (i = 0; i < priv->numActiveLinks; i++) {
1431 struct ng_ppp_link *const alink =
1432 &priv->links[priv->activeLinks[i]];
1433
1434 if (MP_RECV_SEQ_DIFF(priv,
1435 alink->seq, priv->mseq) < 0)
1436 alink->seq = priv->mseq;
1437 }
1438 }
1439
1440 /* Deliver packet */
1441 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1442 }
1443 }
1444
1445 /*
1446 * Periodically call ng_ppp_frag_checkstale()
1447 */
1448 static void
1449 ng_ppp_frag_timeout(void *arg)
1450 {
1451 const node_p node = arg;
1452 const priv_p priv = node->private;
1453
1454 crit_enter();
1455 /* Handle the race where shutdown happens just before splnet() above */
1456 if ((node->flags & NG_INVALID) != 0) {
1457 ng_unref(node);
1458 crit_exit();
1459 return;
1460 }
1461
1462 /* Reset timer state after timeout */
1463 KASSERT(priv->timerActive, ("%s: !timerActive", __func__));
1464 priv->timerActive = 0;
1465 KASSERT(node->refs > 1, ("%s: refs=%d", __func__, node->refs));
1466 ng_unref(node);
1467
1468 /* Start timer again */
1469 ng_ppp_start_frag_timer(node);
1470
1471 /* Scan the fragment queue */
1472 ng_ppp_frag_checkstale(node);
1473 crit_exit();
1474 }
1475
1476 /*
1477 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1478 * the frame across the individual PPP links and do so.
1479 */
1480 static int
1481 ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1482 {
1483 const priv_p priv = node->private;
1484 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4;
1485 int distrib[NG_PPP_MAX_LINKS];
1486 int firstFragment;
1487 int activeLinkNum;
1488
1489 /* At least one link must be active */
1490 if (priv->numActiveLinks == 0) {
1491 NG_FREE_DATA(m, meta);
1492 return (ENETDOWN);
1493 }
1494
1495 /* Round-robin strategy */
1496 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1497 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1498 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1499 distrib[activeLinkNum] = m->m_pkthdr.len;
1500 goto deliver;
1501 }
1502
1503 /* Strategy when all links are equivalent (optimize the common case) */
1504 if (priv->allLinksEqual) {
1505 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1506 int i, remain;
1507
1508 for (i = 0; i < priv->numActiveLinks; i++)
1509 distrib[priv->lastLink++ % priv->numActiveLinks]
1510 = fraction;
1511 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1512 while (remain > 0) {
1513 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1514 remain--;
1515 }
1516 goto deliver;
1517 }
1518
1519 /* Strategy when all links are not equivalent */
1520 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1521
1522 deliver:
1523 /* Update stats */
1524 priv->bundleStats.xmitFrames++;
1525 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1526
1527 /* Send alloted portions of frame out on the link(s) */
1528 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1529 activeLinkNum >= 0; activeLinkNum--) {
1530 const int linkNum = priv->activeLinks[activeLinkNum];
1531 struct ng_ppp_link *const link = &priv->links[linkNum];
1532
1533 /* Deliver fragment(s) out the next link */
1534 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1535 int len, lastFragment, error;
1536 struct mbuf *m2;
1537 meta_p meta2;
1538
1539 /* Calculate fragment length; don't exceed link MTU */
1540 len = distrib[activeLinkNum];
1541 if (len > link->conf.mru - hdr_len)
1542 len = link->conf.mru - hdr_len;
1543 distrib[activeLinkNum] -= len;
1544 lastFragment = (len == m->m_pkthdr.len);
1545
1546 /* Split off next fragment as "m2" */
1547 m2 = m;
1548 if (!lastFragment) {
1549 struct mbuf *n = m_split(m, len, MB_DONTWAIT);
1550
1551 if (n == NULL) {
1552 NG_FREE_DATA(m, meta);
1553 return (ENOMEM);
1554 }
1555 m = n;
1556 }
1557
1558 /* Prepend MP header */
1559 if (priv->conf.xmitShortSeq) {
1560 u_int16_t shdr;
1561
1562 shdr = priv->xseq;
1563 priv->xseq =
1564 (priv->xseq + 1) & MP_SHORT_SEQ_MASK;
1565 if (firstFragment)
1566 shdr |= MP_SHORT_FIRST_FLAG;
1567 if (lastFragment)
1568 shdr |= MP_SHORT_LAST_FLAG;
1569 shdr = htons(shdr);
1570 m2 = ng_ppp_prepend(m2, &shdr, 2);
1571 } else {
1572 u_int32_t lhdr;
1573
1574 lhdr = priv->xseq;
1575 priv->xseq =
1576 (priv->xseq + 1) & MP_LONG_SEQ_MASK;
1577 if (firstFragment)
1578 lhdr |= MP_LONG_FIRST_FLAG;
1579 if (lastFragment)
1580 lhdr |= MP_LONG_LAST_FLAG;
1581 lhdr = htonl(lhdr);
1582 m2 = ng_ppp_prepend(m2, &lhdr, 4);
1583 }
1584 if (m2 == NULL) {
1585 if (!lastFragment)
1586 m_freem(m);
1587 NG_FREE_META(meta);
1588 return (ENOBUFS);
1589 }
1590
1591 /* Copy the meta information, if any */
1592 meta2 = lastFragment ? meta : ng_copy_meta(meta);
1593
1594 /* Send fragment */
1595 error = ng_ppp_output(node, 0,
1596 PROT_MP, linkNum, m2, meta2);
1597 if (error != 0) {
1598 if (!lastFragment)
1599 NG_FREE_DATA(m, meta);
1600 return (error);
1601 }
1602 }
1603 }
1604
1605 /* Done */
1606 return (0);
1607 }
1608
1609 /*
1610 * Computing the optimal fragmentation
1611 * -----------------------------------
1612 *
1613 * This routine tries to compute the optimal fragmentation pattern based
1614 * on each link's latency, bandwidth, and calculated additional latency.
1615 * The latter quantity is the additional latency caused by previously
1616 * written data that has not been transmitted yet.
1617 *
1618 * This algorithm is only useful when not all of the links have the
1619 * same latency and bandwidth values.
1620 *
1621 * The essential idea is to make the last bit of each fragment of the
1622 * frame arrive at the opposite end at the exact same time. This greedy
1623 * algorithm is optimal, in that no other scheduling could result in any
1624 * packet arriving any sooner unless packets are delivered out of order.
1625 *
1626 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and
1627 * latency l_i (in miliseconds). Consider the function function f_i(t)
1628 * which is equal to the number of bytes that will have arrived at
1629 * the peer after t miliseconds if we start writing continuously at
1630 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i).
1631 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i).
1632 * Note that the y-intersect is always <= zero because latency can't be
1633 * negative. Note also that really the function is f_i(t) except when
1634 * f_i(t) is negative, in which case the function is zero. To take
1635 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }.
1636 * So the actual number of bytes that will have arrived at the peer after
1637 * t miliseconds is f_i(t) * Q_i(t).
1638 *
1639 * At any given time, each link has some additional latency a_i >= 0
1640 * due to previously written fragment(s) which are still in the queue.
1641 * This value is easily computed from the time since last transmission,
1642 * the previous latency value, the number of bytes written, and the
1643 * link's bandwidth.
1644 *
1645 * Assume that l_i includes any a_i already, and that the links are
1646 * sorted by latency, so that l_i <= l_{i+1}.
1647 *
1648 * Let N be the total number of bytes in the current frame we are sending.
1649 *
1650 * Suppose we were to start writing bytes at time t = 0 on all links
1651 * simultaneously, which is the most we can possibly do. Then let
1652 * F(t) be equal to the total number of bytes received by the peer
1653 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)).
1654 *
1655 * Our goal is simply this: fragment the frame across the links such
1656 * that the peer is able to reconstruct the completed frame as soon as
1657 * possible, i.e., at the least possible value of t. Call this value t_0.
1658 *
1659 * Then it follows that F(t_0) = N. Our strategy is first to find the value
1660 * of t_0, and then deduce how many bytes to write to each link.
1661 *
1662 * Rewriting F(t_0):
1663 *
1664 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) )
1665 *
1666 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will
1667 * lie in one of these ranges. To find it, we just need to find the i such
1668 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values
1669 * for Q_i() in this range, plug in the remaining values, solving for t_0.
1670 *
1671 * Once t_0 is known, then the number of bytes to send on link i is
1672 * just f_i(t_0) * Q_i(t_0).
1673 *
1674 * In other words, we start allocating bytes to the links one at a time.
1675 * We keep adding links until the frame is completely sent. Some links
1676 * may not get any bytes because their latency is too high.
1677 *
1678 * Is all this work really worth the trouble? Depends on the situation.
1679 * The bigger the ratio of computer speed to link speed, and the more
1680 * important total bundle latency is (e.g., for interactive response time),
1681 * the more it's worth it. There is however the cost of calling this
1682 * function for every frame. The running time is O(n^2) where n is the
1683 * number of links that receive a non-zero number of bytes.
1684 *
1685 * Since latency is measured in miliseconds, the "resolution" of this
1686 * algorithm is one milisecond.
1687 *
1688 * To avoid this algorithm altogether, configure all links to have the
1689 * same latency and bandwidth.
1690 */
1691 static void
1692 ng_ppp_mp_strategy(node_p node, int len, int *distrib)
1693 {
1694 const priv_p priv = node->private;
1695 int latency[NG_PPP_MAX_LINKS];
1696 int sortByLatency[NG_PPP_MAX_LINKS];
1697 int activeLinkNum;
1698 int t0, total, topSum, botSum;
1699 struct timeval now;
1700 int i, numFragments;
1701
1702 /* If only one link, this gets real easy */
1703 if (priv->numActiveLinks == 1) {
1704 distrib[0] = len;
1705 return;
1706 }
1707
1708 /* Get current time */
1709 getmicrouptime(&now);
1710
1711 /* Compute latencies for each link at this point in time */
1712 for (activeLinkNum = 0;
1713 activeLinkNum < priv->numActiveLinks; activeLinkNum++) {
1714 struct ng_ppp_link *alink;
1715 struct timeval diff;
1716 int xmitBytes;
1717
1718 /* Start with base latency value */
1719 alink = &priv->links[priv->activeLinks[activeLinkNum]];
1720 latency[activeLinkNum] = alink->conf.latency;
1721 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */
1722
1723 /* Any additional latency? */
1724 if (alink->bytesInQueue == 0)
1725 continue;
1726
1727 /* Compute time delta since last write */
1728 diff = now;
1729 timevalsub(&diff, &alink->lastWrite);
1730 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */
1731 alink->bytesInQueue = 0;
1732 continue;
1733 }
1734
1735 /* How many bytes could have transmitted since last write? */
1736 xmitBytes = (alink->conf.bandwidth * diff.tv_sec)
1737 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100;
1738 alink->bytesInQueue -= xmitBytes;
1739 if (alink->bytesInQueue < 0)
1740 alink->bytesInQueue = 0;
1741 else
1742 latency[activeLinkNum] +=
1743 (100 * alink->bytesInQueue) / alink->conf.bandwidth;
1744 }
1745
1746 /* Sort active links by latency */
1747 compareLatencies = latency;
1748 kqsort(sortByLatency,
1749 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp);
1750 compareLatencies = NULL;
1751
1752 /* Find the interval we need (add links in sortByLatency[] order) */
1753 for (numFragments = 1;
1754 numFragments < priv->numActiveLinks; numFragments++) {
1755 for (total = i = 0; i < numFragments; i++) {
1756 int flowTime;
1757
1758 flowTime = latency[sortByLatency[numFragments]]
1759 - latency[sortByLatency[i]];
1760 total += ((flowTime * priv->links[
1761 priv->activeLinks[sortByLatency[i]]].conf.bandwidth)
1762 + 99) / 100;
1763 }
1764 if (total >= len)
1765 break;
1766 }
1767
1768 /* Solve for t_0 in that interval */
1769 for (topSum = botSum = i = 0; i < numFragments; i++) {
1770 int bw = priv->links[
1771 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1772
1773 topSum += latency[sortByLatency[i]] * bw; /* / 100 */
1774 botSum += bw; /* / 100 */
1775 }
1776 t0 = ((len * 100) + topSum + botSum / 2) / botSum;
1777
1778 /* Compute f_i(t_0) all i */
1779 bzero(distrib, priv->numActiveLinks * sizeof(*distrib));
1780 for (total = i = 0; i < numFragments; i++) {
1781 int bw = priv->links[
1782 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1783
1784 distrib[sortByLatency[i]] =
1785 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100;
1786 total += distrib[sortByLatency[i]];
1787 }
1788
1789 /* Deal with any rounding error */
1790 if (total < len) {
1791 struct ng_ppp_link *fastLink =
1792 &priv->links[priv->activeLinks[sortByLatency[0]]];
1793 int fast = 0;
1794
1795 /* Find the fastest link */
1796 for (i = 1; i < numFragments; i++) {
1797 struct ng_ppp_link *const link =
1798 &priv->links[priv->activeLinks[sortByLatency[i]]];
1799
1800 if (link->conf.bandwidth > fastLink->conf.bandwidth) {
1801 fast = i;
1802 fastLink = link;
1803 }
1804 }
1805 distrib[sortByLatency[fast]] += len - total;
1806 } else while (total > len) {
1807 struct ng_ppp_link *slowLink =
1808 &priv->links[priv->activeLinks[sortByLatency[0]]];
1809 int delta, slow = 0;
1810
1811 /* Find the slowest link that still has bytes to remove */
1812 for (i = 1; i < numFragments; i++) {
1813 struct ng_ppp_link *const link =
1814 &priv->links[priv->activeLinks[sortByLatency[i]]];
1815
1816 if (distrib[sortByLatency[slow]] == 0
1817 || (distrib[sortByLatency[i]] > 0
1818 && link->conf.bandwidth <
1819 slowLink->conf.bandwidth)) {
1820 slow = i;
1821 slowLink = link;
1822 }
1823 }
1824 delta = total - len;
1825 if (delta > distrib[sortByLatency[slow]])
1826 delta = distrib[sortByLatency[slow]];
1827 distrib[sortByLatency[slow]] -= delta;
1828 total -= delta;
1829 }
1830 }
1831
1832 /*
1833 * Compare two integers
1834 */
1835 static int
1836 ng_ppp_intcmp(const void *v1, const void *v2)
1837 {
1838 const int index1 = *((const int *) v1);
1839 const int index2 = *((const int *) v2);
1840
1841 return compareLatencies[index1] - compareLatencies[index2];
1842 }
1843
1844 /*
1845 * Prepend a possibly compressed PPP protocol number in front of a frame
1846 */
1847 static struct mbuf *
1848 ng_ppp_addproto(struct mbuf *m, int proto, int compOK)
1849 {
1850 if (compOK && PROT_COMPRESSABLE(proto)) {
1851 u_char pbyte = (u_char)proto;
1852
1853 return ng_ppp_prepend(m, &pbyte, 1);
1854 } else {
1855 u_int16_t pword = htons((u_int16_t)proto);
1856
1857 return ng_ppp_prepend(m, &pword, 2);
1858 }
1859 }
1860
1861 /*
1862 * Prepend some bytes to an mbuf
1863 */
1864 static struct mbuf *
1865 ng_ppp_prepend(struct mbuf *m, const void *buf, int len)
1866 {
1867 M_PREPEND(m, len, MB_DONTWAIT);
1868 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL))
1869 return (NULL);
1870 bcopy(buf, mtod(m, u_char *), len);
1871 return (m);
1872 }
1873
1874 /*
1875 * Update private information that is derived from other private information
1876 */
1877 static void
1878 ng_ppp_update(node_p node, int newConf)
1879 {
1880 const priv_p priv = node->private;
1881 int i;
1882
1883 /* Update active status for VJ Compression */
1884 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL
1885 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL
1886 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL
1887 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL;
1888
1889 /* Increase latency for each link an amount equal to one MP header */
1890 if (newConf) {
1891 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1892 int hdrBytes;
1893
1894 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2)
1895 + (priv->links[i].conf.enableProtoComp ? 1 : 2)
1896 + (priv->conf.xmitShortSeq ? 2 : 4);
1897 priv->links[i].conf.latency +=
1898 ((hdrBytes * priv->links[i].conf.bandwidth) + 50)
1899 / 100;
1900 }
1901 }
1902
1903 /* Update list of active links */
1904 bzero(&priv->activeLinks, sizeof(priv->activeLinks));
1905 priv->numActiveLinks = 0;
1906 priv->allLinksEqual = 1;
1907 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1908 struct ng_ppp_link *const link = &priv->links[i];
1909
1910 /* Is link active? */
1911 if (link->conf.enableLink && link->hook != NULL) {
1912 struct ng_ppp_link *link0;
1913
1914 /* Add link to list of active links */
1915 priv->activeLinks[priv->numActiveLinks++] = i;
1916 link0 = &priv->links[priv->activeLinks[0]];
1917
1918 /* Determine if all links are still equal */
1919 if (link->conf.latency != link0->conf.latency
1920 || link->conf.bandwidth != link0->conf.bandwidth)
1921 priv->allLinksEqual = 0;
1922
1923 /* Initialize rec'd sequence number */
1924 if (link->seq == MP_NOSEQ) {
1925 link->seq = (link == link0) ?
1926 MP_INITIAL_SEQ : link0->seq;
1927 }
1928 } else
1929 link->seq = MP_NOSEQ;
1930 }
1931
1932 /* Update MP state as multi-link is active or not */
1933 if (priv->conf.enableMultilink && priv->numActiveLinks > 0)
1934 ng_ppp_start_frag_timer(node);
1935 else {
1936 ng_ppp_stop_frag_timer(node);
1937 ng_ppp_frag_reset(node);
1938 priv->xseq = MP_INITIAL_SEQ;
1939 priv->mseq = MP_INITIAL_SEQ;
1940 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1941 struct ng_ppp_link *const link = &priv->links[i];
1942
1943 bzero(&link->lastWrite, sizeof(link->lastWrite));
1944 link->bytesInQueue = 0;
1945 link->seq = MP_NOSEQ;
1946 }
1947 }
1948 }
1949
1950 /*
1951 * Determine if a new configuration would represent a valid change
1952 * from the current configuration and link activity status.
1953 */
1954 static int
1955 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf)
1956 {
1957 const priv_p priv = node->private;
1958 int i, newNumLinksActive;
1959
1960 /* Check per-link config and count how many links would be active */
1961 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) {
1962 if (newConf->links[i].enableLink && priv->links[i].hook != NULL)
1963 newNumLinksActive++;
1964 if (!newConf->links[i].enableLink)
1965 continue;
1966 if (newConf->links[i].mru < MP_MIN_LINK_MRU)
1967 return (0);
1968 if (newConf->links[i].bandwidth == 0)
1969 return (0);
1970 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH)
1971 return (0);
1972 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY)
1973 return (0);
1974 }
1975
1976 /* Check bundle parameters */
1977 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU)
1978 return (0);
1979
1980 /* Disallow changes to multi-link configuration while MP is active */
1981 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) {
1982 if (!priv->conf.enableMultilink
1983 != !newConf->bund.enableMultilink
1984 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq
1985 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq)
1986 return (0);
1987 }
1988
1989 /* At most one link can be active unless multi-link is enabled */
1990 if (!newConf->bund.enableMultilink && newNumLinksActive > 1)
1991 return (0);
1992
1993 /* Configuration change would be valid */
1994 return (1);
1995 }
1996
1997 /*
1998 * Free all entries in the fragment queue
1999 */
2000 static void
2001 ng_ppp_frag_reset(node_p node)
2002 {
2003 const priv_p priv = node->private;
2004 struct ng_ppp_frag *qent, *qnext;
2005
2006 for (qent = CIRCLEQ_FIRST(&priv->frags);
2007 qent != (void *)&priv->frags; qent = qnext) {
2008 qnext = CIRCLEQ_NEXT(qent, f_qent);
2009 NG_FREE_DATA(qent->data, qent->meta);
2010 FREE(qent, M_NETGRAPH);
2011 }
2012 CIRCLEQ_INIT(&priv->frags);
2013 priv->qlen = 0;
2014 }
2015
2016 /*
2017 * Start fragment queue timer
2018 */
2019 static void
2020 ng_ppp_start_frag_timer(node_p node)
2021 {
2022 const priv_p priv = node->private;
2023
2024 if (!priv->timerActive) {
2025 callout_reset(&priv->fragTimer, MP_FRAGTIMER_INTERVAL,
2026 ng_ppp_frag_timeout, node);
2027 priv->timerActive = 1;
2028 node->refs++;
2029 }
2030 }
2031
2032 /*
2033 * Stop fragment queue timer
2034 */
2035 static void
2036 ng_ppp_stop_frag_timer(node_p node)
2037 {
2038 const priv_p priv = node->private;
2039
2040 if (priv->timerActive) {
2041 callout_stop(&priv->fragTimer);
2042 priv->timerActive = 0;
2043 KASSERT(node->refs > 1,
2044 ("%s: refs=%d", __func__, node->refs));
2045 ng_unref(node);
2046 }
2047 }
2048
DragonFly BSD