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/ctype.h>
55
56#include <machine/limits.h>
57
58#include <netgraph/ng_message.h>
59#include <netgraph/netgraph.h>
60#include <netgraph/ng_parse.h>
61#include <netgraph/ng_ppp.h>
62#include <netgraph/ng_vjc.h>
63
64#ifdef NG_SEPARATE_MALLOC
65MALLOC_DEFINE(M_NETGRAPH_PPP, "netgraph_ppp", "netgraph ppp node");
66#else
67#define M_NETGRAPH_PPP M_NETGRAPH
68#endif
69
70#define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
71#define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
72
73/* Some PPP protocol numbers we're interested in */
74#define PROT_APPLETALK 0x0029
75#define PROT_COMPD 0x00fd
76#define PROT_CRYPTD 0x0053
77#define PROT_IP 0x0021
78#define PROT_IPV6 0x0057
79#define PROT_IPX 0x002b
80#define PROT_LCP 0xc021
81#define PROT_MP 0x003d
82#define PROT_VJCOMP 0x002d
83#define PROT_VJUNCOMP 0x002f
84
85/* Multilink PPP definitions */
86#define MP_MIN_MRRU 1500 /* per RFC 1990 */
87#define MP_INITIAL_SEQ 0 /* per RFC 1990 */
88#define MP_MIN_LINK_MRU 32
89
90#define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
91#define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
92#define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
93#define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
94
95#define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
96#define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
97#define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
98#define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
99
100#define MP_NOSEQ 0x7fffffff /* impossible sequence number */
101
102/* Sign extension of MP sequence numbers */
103#define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
104 ((s) | ~MP_SHORT_SEQ_MASK) \
105 : ((s) & MP_SHORT_SEQ_MASK))
106#define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
107 ((s) | ~MP_LONG_SEQ_MASK) \
108 : ((s) & MP_LONG_SEQ_MASK))
109
110/* Comparision of MP sequence numbers. Note: all sequence numbers
111 except priv->xseq are stored with the sign bit extended. */
112#define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y))
113#define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y))
114
115#define MP_RECV_SEQ_DIFF(priv,x,y) \
116 ((priv)->conf.recvShortSeq ? \
117 MP_SHORT_SEQ_DIFF((x), (y)) : \
118 MP_LONG_SEQ_DIFF((x), (y)))
119
120/* Increment receive sequence number */
121#define MP_NEXT_RECV_SEQ(priv,seq) \
122 ((priv)->conf.recvShortSeq ? \
123 MP_SHORT_EXTEND((seq) + 1) : \
124 MP_LONG_EXTEND((seq) + 1))
125
126/* Don't fragment transmitted packets smaller than this */
127#define MP_MIN_FRAG_LEN 6
128
129/* Maximum fragment reasssembly queue length */
130#define MP_MAX_QUEUE_LEN 128
131
132/* Fragment queue scanner period */
133#define MP_FRAGTIMER_INTERVAL (hz/2)
134
135/* We store incoming fragments this way */
136struct ng_ppp_frag {
137 int seq; /* fragment seq# */
138 u_char first; /* First in packet? */
139 u_char last; /* Last in packet? */
140 struct timeval timestamp; /* time of reception */
141 struct mbuf *data; /* Fragment data */
142 meta_p meta; /* Fragment meta */
143 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
144};
145
146/* We use integer indicies to refer to the non-link hooks */
147static const char *const ng_ppp_hook_names[] = {
148 NG_PPP_HOOK_ATALK,
149#define HOOK_INDEX_ATALK 0
150 NG_PPP_HOOK_BYPASS,
151#define HOOK_INDEX_BYPASS 1
152 NG_PPP_HOOK_COMPRESS,
153#define HOOK_INDEX_COMPRESS 2
154 NG_PPP_HOOK_ENCRYPT,
155#define HOOK_INDEX_ENCRYPT 3
156 NG_PPP_HOOK_DECOMPRESS,
157#define HOOK_INDEX_DECOMPRESS 4
158 NG_PPP_HOOK_DECRYPT,
159#define HOOK_INDEX_DECRYPT 5
160 NG_PPP_HOOK_INET,
161#define HOOK_INDEX_INET 6
162 NG_PPP_HOOK_IPX,
163#define HOOK_INDEX_IPX 7
164 NG_PPP_HOOK_VJC_COMP,
165#define HOOK_INDEX_VJC_COMP 8
166 NG_PPP_HOOK_VJC_IP,
167#define HOOK_INDEX_VJC_IP 9
168 NG_PPP_HOOK_VJC_UNCOMP,
169#define HOOK_INDEX_VJC_UNCOMP 10
170 NG_PPP_HOOK_VJC_VJIP,
171#define HOOK_INDEX_VJC_VJIP 11
172 NG_PPP_HOOK_IPV6,
173#define HOOK_INDEX_IPV6 12
174 NULL
175#define HOOK_INDEX_MAX 13
176};
177
178/* We store index numbers in the hook private pointer. The HOOK_INDEX()
179 for a hook is either the index (above) for normal hooks, or the ones
180 complement of the link number for link hooks.
181XXX Not any more.. (what a hack)
182#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
183*/
184
185/* Per-link private information */
186struct ng_ppp_link {
187 struct ng_ppp_link_conf conf; /* link configuration */
188 hook_p hook; /* connection to link data */
189 int32_t seq; /* highest rec'd seq# - MSEQ */
190 struct timeval lastWrite; /* time of last write */
191 int bytesInQueue; /* bytes in the output queue */
192 struct ng_ppp_link_stat stats; /* Link stats */
193};
194
195/* Total per-node private information */
196struct ng_ppp_private {
197 struct ng_ppp_bund_conf conf; /* bundle config */
198 struct ng_ppp_link_stat bundleStats; /* bundle stats */
199 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
200 int32_t xseq; /* next out MP seq # */
201 int32_t mseq; /* min links[i].seq */
202 u_char vjCompHooked; /* VJ comp hooked up? */
203 u_char allLinksEqual; /* all xmit the same? */
204 u_char timerActive; /* frag timer active? */
205 u_int numActiveLinks; /* how many links up */
206 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
207 u_int lastLink; /* for round robin */
208 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
209 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
210 frags;
211 int qlen; /* fraq queue length */
212 struct callout_handle fragTimer; /* fraq queue check */
213};
214typedef struct ng_ppp_private *priv_p;
215
216/* Netgraph node methods */
217static ng_constructor_t ng_ppp_constructor;
218static ng_rcvmsg_t ng_ppp_rcvmsg;
219static ng_shutdown_t ng_ppp_shutdown;
220static ng_newhook_t ng_ppp_newhook;
221static ng_rcvdata_t ng_ppp_rcvdata;
222static ng_disconnect_t ng_ppp_disconnect;
223
224/* Helper functions */
225static int ng_ppp_input(node_p node, int bypass,
226 int linkNum, item_p item);
227static int ng_ppp_output(node_p node, int bypass, int proto,
228 int linkNum, item_p item);
229static int ng_ppp_mp_input(node_p node, int linkNum, item_p item);
230static int ng_ppp_check_packet(node_p node);
231static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
232static int ng_ppp_frag_process(node_p node);
233static int ng_ppp_frag_trim(node_p node);
234static void ng_ppp_frag_timeout(void *arg);
235static void ng_ppp_frag_checkstale(node_p node);
236static void ng_ppp_frag_reset(node_p node);
237static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
238static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
239static int ng_ppp_intcmp(const void *v1, const void *v2);
240static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
241static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
242static int ng_ppp_config_valid(node_p node,
243 const struct ng_ppp_node_conf *newConf);
244static void ng_ppp_update(node_p node, int newConf);
245static void ng_ppp_start_frag_timer(node_p node);
246static void ng_ppp_stop_frag_timer(node_p node);
247
248/* Parse type for struct ng_ppp_mp_state_type */
249static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = {
250 &ng_parse_hint32_type,
251 NG_PPP_MAX_LINKS
252};
253static const struct ng_parse_type ng_ppp_rseq_array_type = {
254 &ng_parse_fixedarray_type,
255 &ng_ppp_rseq_array_info,
256};
257static const struct ng_parse_struct_field ng_ppp_mp_state_type_fields[]
258 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type);
259static const struct ng_parse_type ng_ppp_mp_state_type = {
260 &ng_parse_struct_type,
261 &ng_ppp_mp_state_type_fields
262};
263
264/* Parse type for struct ng_ppp_link_conf */
265static const struct ng_parse_struct_field ng_ppp_link_type_fields[]
266 = NG_PPP_LINK_TYPE_INFO;
267static const struct ng_parse_type ng_ppp_link_type = {
268 &ng_parse_struct_type,
269 &ng_ppp_link_type_fields
270};
271
272/* Parse type for struct ng_ppp_bund_conf */
273static const struct ng_parse_struct_field ng_ppp_bund_type_fields[]
274 = NG_PPP_BUND_TYPE_INFO;
275static const struct ng_parse_type ng_ppp_bund_type = {
276 &ng_parse_struct_type,
277 &ng_ppp_bund_type_fields
278};
279
280/* Parse type for struct ng_ppp_node_conf */
281static const struct ng_parse_fixedarray_info ng_ppp_array_info = {
282 &ng_ppp_link_type,
283 NG_PPP_MAX_LINKS
284};
285static const struct ng_parse_type ng_ppp_link_array_type = {
286 &ng_parse_fixedarray_type,
287 &ng_ppp_array_info,
288};
289static const struct ng_parse_struct_field ng_ppp_conf_type_fields[]
290 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
291static const struct ng_parse_type ng_ppp_conf_type = {
292 &ng_parse_struct_type,
293 &ng_ppp_conf_type_fields
294};
295
296/* Parse type for struct ng_ppp_link_stat */
297static const struct ng_parse_struct_field ng_ppp_stats_type_fields[]
298 = NG_PPP_STATS_TYPE_INFO;
299static const struct ng_parse_type ng_ppp_stats_type = {
300 &ng_parse_struct_type,
301 &ng_ppp_stats_type_fields
302};
303
304/* List of commands and how to convert arguments to/from ASCII */
305static const struct ng_cmdlist ng_ppp_cmds[] = {
306 {
307 NGM_PPP_COOKIE,
308 NGM_PPP_SET_CONFIG,
309 "setconfig",
310 &ng_ppp_conf_type,
311 NULL
312 },
313 {
314 NGM_PPP_COOKIE,
315 NGM_PPP_GET_CONFIG,
316 "getconfig",
317 NULL,
318 &ng_ppp_conf_type
319 },
320 {
321 NGM_PPP_COOKIE,
322 NGM_PPP_GET_MP_STATE,
323 "getmpstate",
324 NULL,
325 &ng_ppp_mp_state_type
326 },
327 {
328 NGM_PPP_COOKIE,
329 NGM_PPP_GET_LINK_STATS,
330 "getstats",
331 &ng_parse_int16_type,
332 &ng_ppp_stats_type
333 },
334 {
335 NGM_PPP_COOKIE,
336 NGM_PPP_CLR_LINK_STATS,
337 "clrstats",
338 &ng_parse_int16_type,
339 NULL
340 },
341 {
342 NGM_PPP_COOKIE,
343 NGM_PPP_GETCLR_LINK_STATS,
344 "getclrstats",
345 &ng_parse_int16_type,
346 &ng_ppp_stats_type
347 },
348 { 0 }
349};
350
351/* Node type descriptor */
352static struct ng_type ng_ppp_typestruct = {
353 NG_ABI_VERSION,
354 NG_PPP_NODE_TYPE,
355 NULL,
356 ng_ppp_constructor,
357 ng_ppp_rcvmsg,
358 ng_ppp_shutdown,
359 ng_ppp_newhook,
360 NULL,
361 NULL,
362 ng_ppp_rcvdata,
363 ng_ppp_disconnect,
364 ng_ppp_cmds
365};
366NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
367
368static int *compareLatencies; /* hack for ng_ppp_intcmp() */
369
370/* Address and control field header */
371static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
372
373/* Maximum time we'll let a complete incoming packet sit in the queue */
374static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
375
376#define ERROUT(x) do { error = (x); goto done; } while (0)
377
378/************************************************************************
379 NETGRAPH NODE STUFF
380 ************************************************************************/
381
382/*
383 * Node type constructor
384 */
385static int
386ng_ppp_constructor(node_p node)
387{
388 priv_p priv;
389 int i;
390
391 /* Allocate private structure */
392 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_PPP, M_NOWAIT | M_ZERO);
393 if (priv == NULL)
394 return (ENOMEM);
395
396 NG_NODE_SET_PRIVATE(node, priv);
397
398 /* Initialize state */
399 TAILQ_INIT(&priv->frags);
400 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
401 priv->links[i].seq = MP_NOSEQ;
402 callout_handle_init(&priv->fragTimer);
403
404 /* Done */
405 return (0);
406}
407
408/*
409 * Give our OK for a hook to be added
410 */
411static int
412ng_ppp_newhook(node_p node, hook_p hook, const char *name)
413{
414 const priv_p priv = NG_NODE_PRIVATE(node);
415 int linkNum = -1;
416 hook_p *hookPtr = NULL;
417 int hookIndex = -1;
418
419 /* Figure out which hook it is */
420 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
421 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
422 const char *cp;
423 char *eptr;
424
425 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
426 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
427 return (EINVAL);
428 linkNum = (int)strtoul(cp, &eptr, 10);
429 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
430 return (EINVAL);
431 hookPtr = &priv->links[linkNum].hook;
432 hookIndex = ~linkNum;
433 } else { /* must be a non-link hook */
434 int i;
435
436 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
437 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
438 hookPtr = &priv->hooks[i];
439 hookIndex = i;
440 break;
441 }
442 }
443 if (ng_ppp_hook_names[i] == NULL)
444 return (EINVAL); /* no such hook */
445 }
446
447 /* See if hook is already connected */
448 if (*hookPtr != NULL)
449 return (EISCONN);
450
451 /* Disallow more than one link unless multilink is enabled */
452 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
453 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
454 return (ENODEV);
455
456 /* OK */
457 *hookPtr = hook;
458 NG_HOOK_SET_PRIVATE(hook, (void *)(intptr_t)hookIndex);
459 ng_ppp_update(node, 0);
460 return (0);
461}
462
463/*
464 * Receive a control message
465 */
466static int
467ng_ppp_rcvmsg(node_p node, item_p item, hook_p lasthook)
468{
469 const priv_p priv = NG_NODE_PRIVATE(node);
470 struct ng_mesg *resp = NULL;
471 int error = 0;
472 struct ng_mesg *msg;
473
474 NGI_GET_MSG(item, msg);
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 /*
563 * Forward it to the vjc node. leave the
564 * old return address alone.
565 * If we have no hook, let NG_RESPOND_MSG
566 * clean up any remaining resources.
567 * Because we have no resp, the item will be freed
568 * along with anything it references. Don't
569 * let msg be freed twice.
570 */
571 NGI_MSG(item) = msg; /* put it back in the item */
572 msg = NULL;
573 if ((lasthook = priv->links[HOOK_INDEX_VJC_IP].hook)) {
574 NG_FWD_ITEM_HOOK(error, item, lasthook);
575 }
576 return (error);
577 }
578 default:
579 error = EINVAL;
580 break;
581 }
582done:
583 NG_RESPOND_MSG(error, node, item, resp);
584 NG_FREE_MSG(msg);
585 return (error);
586}
587
588/*
589 * Receive data on a hook
590 */
591static int
592ng_ppp_rcvdata(hook_p hook, item_p item)
593{
594 const node_p node = NG_HOOK_NODE(hook);
595 const priv_p priv = NG_NODE_PRIVATE(node);
596 const int index = (intptr_t)NG_HOOK_PRIVATE(hook);
597 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
598 hook_p outHook = NULL;
599 int proto = 0, error;
600 struct mbuf *m;
601
602 NGI_GET_M(item, m);
603 /* Did it come from a link hook? */
604 if (index < 0) {
605 struct ng_ppp_link *link;
606
607 /* Convert index into a link number */
608 linkNum = (u_int16_t)~index;
609 KASSERT(linkNum < NG_PPP_MAX_LINKS,
610 ("%s: bogus index 0x%x", __func__, index));
611 link = &priv->links[linkNum];
612
613 /* Stats */
614 link->stats.recvFrames++;
615 link->stats.recvOctets += m->m_pkthdr.len;
616
617 /* Strip address and control fields, if present */
618 if (m->m_pkthdr.len >= 2) {
619 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
620 NG_FREE_ITEM(item);
621 return (ENOBUFS);
622 }
623 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
624 m_adj(m, 2);
625 }
626
627 /* Dispatch incoming frame (if not enabled, to bypass) */
628 NGI_M(item) = m; /* put changed m back in item */
629 return ng_ppp_input(node,
630 !link->conf.enableLink, linkNum, item);
631 }
632
633 /* Get protocol & check if data allowed from this hook */
634 NGI_M(item) = m; /* put possibly changed m back in item */
635 switch (index) {
636
637 /* Outgoing data */
638 case HOOK_INDEX_ATALK:
639 if (!priv->conf.enableAtalk) {
640 NG_FREE_ITEM(item);
641 return (ENXIO);
642 }
643 proto = PROT_APPLETALK;
644 break;
645 case HOOK_INDEX_IPX:
646 if (!priv->conf.enableIPX) {
647 NG_FREE_ITEM(item);
648 return (ENXIO);
649 }
650 proto = PROT_IPX;
651 break;
652 case HOOK_INDEX_IPV6:
653 if (!priv->conf.enableIPv6) {
654 NG_FREE_ITEM(item);
655 return (ENXIO);
656 }
657 proto = PROT_IPV6;
658 break;
659 case HOOK_INDEX_INET:
660 case HOOK_INDEX_VJC_VJIP:
661 if (!priv->conf.enableIP) {
662 NG_FREE_ITEM(item);
663 return (ENXIO);
664 }
665 proto = PROT_IP;
666 break;
667 case HOOK_INDEX_VJC_COMP:
668 if (!priv->conf.enableVJCompression) {
669 NG_FREE_ITEM(item);
670 return (ENXIO);
671 }
672 proto = PROT_VJCOMP;
673 break;
674 case HOOK_INDEX_VJC_UNCOMP:
675 if (!priv->conf.enableVJCompression) {
676 NG_FREE_ITEM(item);
677 return (ENXIO);
678 }
679 proto = PROT_VJUNCOMP;
680 break;
681 case HOOK_INDEX_COMPRESS:
682 if (!priv->conf.enableCompression) {
683 NG_FREE_ITEM(item);
684 return (ENXIO);
685 }
686 proto = PROT_COMPD;
687 break;
688 case HOOK_INDEX_ENCRYPT:
689 if (!priv->conf.enableEncryption) {
690 NG_FREE_ITEM(item);
691 return (ENXIO);
692 }
693 proto = PROT_CRYPTD;
694 break;
695 case HOOK_INDEX_BYPASS:
696 if (m->m_pkthdr.len < 4) {
697 NG_FREE_ITEM(item);
698 return (EINVAL);
699 }
700 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
701 NGI_M(item) = NULL; /* don't free twice */
702 NG_FREE_ITEM(item);
703 return (ENOBUFS);
704 }
705 NGI_M(item) = m; /* m may have changed */
706 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
707 proto = ntohs(mtod(m, u_int16_t *)[1]);
708 m_adj(m, 4);
709 if (linkNum >= NG_PPP_MAX_LINKS
710 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
711 NG_FREE_ITEM(item);
712 return (EINVAL);
713 }
714 break;
715
716 /* Incoming data */
717 case HOOK_INDEX_VJC_IP:
718 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
719 NG_FREE_ITEM(item);
720 return (ENXIO);
721 }
722 break;
723 case HOOK_INDEX_DECOMPRESS:
724 if (!priv->conf.enableDecompression) {
725 NG_FREE_ITEM(item);
726 return (ENXIO);
727 }
728 break;
729 case HOOK_INDEX_DECRYPT:
730 if (!priv->conf.enableDecryption) {
731 NG_FREE_ITEM(item);
732 return (ENXIO);
733 }
734 break;
735 default:
736 panic("%s: bogus index 0x%x", __func__, index);
737 }
738
739 /* Now figure out what to do with the frame */
740 switch (index) {
741
742 /* Outgoing data */
743 case HOOK_INDEX_INET:
744 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
745 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
746 break;
747 }
748 /* FALLTHROUGH */
749 case HOOK_INDEX_ATALK:
750 case HOOK_INDEX_IPV6:
751 case HOOK_INDEX_IPX:
752 case HOOK_INDEX_VJC_COMP:
753 case HOOK_INDEX_VJC_UNCOMP:
754 case HOOK_INDEX_VJC_VJIP:
755 if (priv->conf.enableCompression
756 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
757 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
758 NGI_M(item) = NULL;
759 NG_FREE_ITEM(item);
760 return (ENOBUFS);
761 }
762 NGI_M(item) = m; /* m may have changed */
763 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
764 break;
765 }
766 /* FALLTHROUGH */
767 case HOOK_INDEX_COMPRESS:
768 if (priv->conf.enableEncryption
769 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
770 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
771 NGI_M(item) = NULL;
772 NG_FREE_ITEM(item);
773 return (ENOBUFS);
774 }
775 NGI_M(item) = m; /* m may have changed */
776 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
777 break;
778 }
779 /* FALLTHROUGH */
780 case HOOK_INDEX_ENCRYPT:
781 return ng_ppp_output(node, 0, proto, NG_PPP_BUNDLE_LINKNUM, item);
782
783 case HOOK_INDEX_BYPASS:
784 return ng_ppp_output(node, 1, proto, linkNum, item);
785
786 /* Incoming data */
787 case HOOK_INDEX_DECRYPT:
788 case HOOK_INDEX_DECOMPRESS:
789 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
790
791 case HOOK_INDEX_VJC_IP:
792 outHook = priv->hooks[HOOK_INDEX_INET];
793 break;
794 }
795
796 /* Send packet out hook */
797 NG_FWD_ITEM_HOOK(error, item, outHook);
798 return (error);
799}
800
801/*
802 * Destroy node
803 */
804static int
805ng_ppp_shutdown(node_p node)
806{
807 const priv_p priv = NG_NODE_PRIVATE(node);
808
809 /* Stop fragment queue timer */
810 ng_ppp_stop_frag_timer(node);
811
812 /* Take down netgraph node */
813 ng_ppp_frag_reset(node);
814 bzero(priv, sizeof(*priv));
815 FREE(priv, M_NETGRAPH_PPP);
816 NG_NODE_SET_PRIVATE(node, NULL);
817 NG_NODE_UNREF(node); /* let the node escape */
818 return (0);
819}
820
821/*
822 * Hook disconnection
823 */
824static int
825ng_ppp_disconnect(hook_p hook)
826{
827 const node_p node = NG_HOOK_NODE(hook);
828 const priv_p priv = NG_NODE_PRIVATE(node);
829 const int index = (intptr_t)NG_HOOK_PRIVATE(hook);
830
831 /* Zero out hook pointer */
832 if (index < 0)
833 priv->links[~index].hook = NULL;
834 else
835 priv->hooks[index] = NULL;
836
837 /* Update derived info (or go away if no hooks left) */
838 if (NG_NODE_NUMHOOKS(node) > 0) {
839 ng_ppp_update(node, 0);
840 } else {
841 if (NG_NODE_IS_VALID(node)) {
842 ng_rmnode_self(node);
843 }
844 }
845 return (0);
846}
847
848/************************************************************************
849 HELPER STUFF
850 ************************************************************************/
851
852/*
853 * Handle an incoming frame. Extract the PPP protocol number
854 * and dispatch accordingly.
855 */
856static int
857ng_ppp_input(node_p node, int bypass, int linkNum, item_p item)
858{
859 const priv_p priv = NG_NODE_PRIVATE(node);
860 hook_p outHook = NULL;
861 int proto, error;
862 struct mbuf *m;
863
864
865 NGI_GET_M(item, m);
866 /* Extract protocol number */
867 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
868 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
869 NG_FREE_ITEM(item);
870 return (ENOBUFS);
871 }
872 proto = (proto << 8) + *mtod(m, u_char *);
873 m_adj(m, 1);
874 }
875 if (!PROT_VALID(proto)) {
876 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
877 priv->bundleStats.badProtos++;
878 else
879 priv->links[linkNum].stats.badProtos++;
880 NG_FREE_ITEM(item);
881 NG_FREE_M(m);
882 return (EINVAL);
883 }
884
885 /* Bypass frame? */
886 if (bypass)
887 goto bypass;
888
889 /* Check protocol */
890 switch (proto) {
891 case PROT_COMPD:
892 if (priv->conf.enableDecompression)
893 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
894 break;
895 case PROT_CRYPTD:
896 if (priv->conf.enableDecryption)
897 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
898 break;
899 case PROT_VJCOMP:
900 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
901 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
902 break;
903 case PROT_VJUNCOMP:
904 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
905 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
906 break;
907 case PROT_MP:
908 if (priv->conf.enableMultilink
909 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
910 NGI_M(item) = m;
911 return ng_ppp_mp_input(node, linkNum, item);
912 }
913 break;
914 case PROT_APPLETALK:
915 if (priv->conf.enableAtalk)
916 outHook = priv->hooks[HOOK_INDEX_ATALK];
917 break;
918 case PROT_IPX:
919 if (priv->conf.enableIPX)
920 outHook = priv->hooks[HOOK_INDEX_IPX];
921 break;
922 case PROT_IP:
923 if (priv->conf.enableIP)
924 outHook = priv->hooks[HOOK_INDEX_INET];
925 break;
926 case PROT_IPV6:
927 if (priv->conf.enableIPv6)
928 outHook = priv->hooks[HOOK_INDEX_IPV6];
929 break;
930 }
931
932bypass:
933 /* For unknown/inactive protocols, forward out the bypass hook */
934 if (outHook == NULL) {
935 u_int16_t hdr[2];
936
937 hdr[0] = htons(linkNum);
938 hdr[1] = htons((u_int16_t)proto);
939 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
940 NG_FREE_ITEM(item);
941 return (ENOBUFS);
942 }
943 outHook = priv->hooks[HOOK_INDEX_BYPASS];
944 }
945
946 /* Forward frame */
947 NG_FWD_NEW_DATA(error, item, outHook, m);
948 return (error);
949}
950
951/*
952 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM.
953 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
954 *
955 * If the frame is too big for the particular link, return EMSGSIZE.
956 */
957static int
958ng_ppp_output(node_p node, int bypass,
959 int proto, int linkNum, item_p item)
960{
961 const priv_p priv = NG_NODE_PRIVATE(node);
962 struct ng_ppp_link *link;
963 int len, error;
964 struct mbuf *m;
965 u_int16_t mru;
966
967 /* Extract mbuf */
968 NGI_GET_M(item, m);
969
970 /* If not doing MP, map bundle virtual link to (the only) link */
971 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
972 linkNum = priv->activeLinks[0];
973
974 /* Get link pointer (optimization) */
975 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
976 &priv->links[linkNum] : NULL;
977
978 /* Check link status (if real) */
979 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
980 if (!bypass && !link->conf.enableLink) {
981 NG_FREE_M(m);
982 NG_FREE_ITEM(item);
983 return (ENXIO);
984 }
985 if (link->hook == NULL) {
986 NG_FREE_M(m);
987 NG_FREE_ITEM(item);
988 return (ENETDOWN);
989 }
990 }
991
992 /* Check peer's MRU for this link */
993 mru = (link != NULL) ? link->conf.mru : priv->conf.mrru;
994 if (mru != 0 && m->m_pkthdr.len > mru) {
995 NG_FREE_M(m);
996 NG_FREE_ITEM(item);
997 return (EMSGSIZE);
998 }
999
1000 /* Prepend protocol number, possibly compressed */
1001 if ((m = ng_ppp_addproto(m, proto,
1002 linkNum == NG_PPP_BUNDLE_LINKNUM
1003 || link->conf.enableProtoComp)) == NULL) {
1004 NG_FREE_ITEM(item);
1005 return (ENOBUFS);
1006 }
1007
1008 /* Special handling for the MP virtual link */
1009 if (linkNum == NG_PPP_BUNDLE_LINKNUM) {
1010 meta_p meta;
1011
1012 /* strip off and discard the queue item */
1013 NGI_GET_META(item, meta);
1014 NG_FREE_ITEM(item);
1015 return ng_ppp_mp_output(node, m, meta);
1016 }
1017
1018 /* Prepend address and control field (unless compressed) */
1019 if (proto == PROT_LCP || !link->conf.enableACFComp) {
1020 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
1021 NG_FREE_ITEM(item);
1022 return (ENOBUFS);
1023 }
1024 }
1025
1026 /* Deliver frame */
1027 len = m->m_pkthdr.len;
1028 NG_FWD_NEW_DATA(error, item, link->hook, m);
1029
1030 /* Update stats and 'bytes in queue' counter */
1031 if (error == 0) {
1032 link->stats.xmitFrames++;
1033 link->stats.xmitOctets += len;
1034 link->bytesInQueue += len;
1035 getmicrouptime(&link->lastWrite);
1036 }
1037 return error;
1038}
1039
1040/*
1041 * Handle an incoming multi-link fragment
1042 *
1043 * The fragment reassembly algorithm is somewhat complex. This is mainly
1044 * because we are required not to reorder the reconstructed packets, yet
1045 * fragments are only guaranteed to arrive in order on a per-link basis.
1046 * In other words, when we have a complete packet ready, but the previous
1047 * packet is still incomplete, we have to decide between delivering the
1048 * complete packet and throwing away the incomplete one, or waiting to
1049 * see if the remainder of the incomplete one arrives, at which time we
1050 * can deliver both packets, in order.
1051 *
1052 * This problem is exacerbated by "sequence number slew", which is when
1053 * the sequence numbers coming in from different links are far apart from
1054 * each other. In particular, certain unnamed equipment (*cough* Ascend)
1055 * has been seen to generate sequence number slew of up to 10 on an ISDN
1056 * 2B-channel MP link. There is nothing invalid about sequence number slew
1057 * but it makes the reasssembly process have to work harder.
1058 *
1059 * However, the peer is required to transmit fragments in order on each
1060 * link. That means if we define MSEQ as the minimum over all links of
1061 * the highest sequence number received on that link, then we can always
1062 * give up any hope of receiving a fragment with sequence number < MSEQ in
1063 * the future (all of this using 'wraparound' sequence number space).
1064 * Therefore we can always immediately throw away incomplete packets
1065 * missing fragments with sequence numbers < MSEQ.
1066 *
1067 * Here is an overview of our algorithm:
1068 *
1069 * o Received fragments are inserted into a queue, for which we
1070 * maintain these invariants between calls to this function:
1071 *
1072 * - Fragments are ordered in the queue by sequence number
1073 * - If a complete packet is at the head of the queue, then
1074 * the first fragment in the packet has seq# > MSEQ + 1
1075 * (otherwise, we could deliver it immediately)
1076 * - If any fragments have seq# < MSEQ, then they are necessarily
1077 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
1078 * we can throw them away because they'll never be completed)
1079 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
1080 *
1081 * o We have a periodic timer that checks the queue for the first
1082 * complete packet that has been sitting in the queue "too long".
1083 * When one is detected, all previous (incomplete) fragments are
1084 * discarded, their missing fragments are declared lost and MSEQ
1085 * is increased.
1086 *
1087 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1088 * because we've already delcared it lost.
1089 *
1090 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1091 */
1092static int
1093ng_ppp_mp_input(node_p node, int linkNum, item_p item)
1094{
1095 const priv_p priv = NG_NODE_PRIVATE(node);
1096 struct ng_ppp_link *const link = &priv->links[linkNum];
1097 struct ng_ppp_frag frag0, *frag = &frag0;
1098 struct ng_ppp_frag *qent;
1099 int i, diff, inserted;
1100 struct mbuf *m;
1101 meta_p meta;
1102
1103 NGI_GET_M(item, m);
1104 NGI_GET_META(item, meta);
1105 NG_FREE_ITEM(item);
1106 /* Stats */
1107 priv->bundleStats.recvFrames++;
1108 priv->bundleStats.recvOctets += m->m_pkthdr.len;
1109
1110 /* Extract fragment information from MP header */
1111 if (priv->conf.recvShortSeq) {
1112 u_int16_t shdr;
1113
1114 if (m->m_pkthdr.len < 2) {
1115 link->stats.runts++;
1116 NG_FREE_M(m);
1117 NG_FREE_META(meta);
1118 return (EINVAL);
1119 }
1120 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1121 NG_FREE_META(meta);
1122 return (ENOBUFS);
1123 }
1124 shdr = ntohs(*mtod(m, u_int16_t *));
1125 frag->seq = MP_SHORT_EXTEND(shdr);
1126 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1127 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1128 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1129 m_adj(m, 2);
1130 } else {
1131 u_int32_t lhdr;
1132
1133 if (m->m_pkthdr.len < 4) {
1134 link->stats.runts++;
1135 NG_FREE_M(m);
1136 NG_FREE_META(meta);
1137 return (EINVAL);
1138 }
1139 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1140 NG_FREE_META(meta);
1141 return (ENOBUFS);
1142 }
1143 lhdr = ntohl(*mtod(m, u_int32_t *));
1144 frag->seq = MP_LONG_EXTEND(lhdr);
1145 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1146 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1147 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1148 m_adj(m, 4);
1149 }
1150 frag->data = m;
1151 frag->meta = meta;
1152 getmicrouptime(&frag->timestamp);
1153
1154 /* If sequence number is < MSEQ, we've already declared this
1155 fragment as lost, so we have no choice now but to drop it */
1156 if (diff < 0) {
1157 link->stats.dropFragments++;
1158 NG_FREE_M(m);
1159 NG_FREE_META(meta);
1160 return (0);
1161 }
1162
1163 /* Update highest received sequence number on this link and MSEQ */
1164 priv->mseq = link->seq = frag->seq;
1165 for (i = 0; i < priv->numActiveLinks; i++) {
1166 struct ng_ppp_link *const alink =
1167 &priv->links[priv->activeLinks[i]];
1168
1169 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1170 priv->mseq = alink->seq;
1171 }
1172
1173 /* Allocate a new frag struct for the queue */
1174 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH_PPP, M_NOWAIT);
1175 if (frag == NULL) {
1176 NG_FREE_M(m);
1177 NG_FREE_META(meta);
1178 ng_ppp_frag_process(node);
1179 return (ENOMEM);
1180 }
1181 *frag = frag0;
1182
1183 /* Add fragment to queue, which is sorted by sequence number */
1184 inserted = 0;
1185 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) {
1186 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq);
1187 if (diff > 0) {
1188 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1189 inserted = 1;
1190 break;
1191 } else if (diff == 0) { /* should never happen! */
1192 link->stats.dupFragments++;
1193 NG_FREE_M(frag->data);
1194 NG_FREE_META(frag->meta);
1195 FREE(frag, M_NETGRAPH_PPP);
1196 return (EINVAL);
1197 }
1198 }
1199 if (!inserted)
1200 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1201 priv->qlen++;
1202
1203 /* Process the queue */
1204 return ng_ppp_frag_process(node);
1205}
1206
1207/*
1208 * Examine our list of fragments, and determine if there is a
1209 * complete and deliverable packet at the head of the list.
1210 * Return 1 if so, zero otherwise.
1211 */
1212static int
1213ng_ppp_check_packet(node_p node)
1214{
1215 const priv_p priv = NG_NODE_PRIVATE(node);
1216 struct ng_ppp_frag *qent, *qnext;
1217
1218 /* Check for empty queue */
1219 if (TAILQ_EMPTY(&priv->frags))
1220 return (0);
1221
1222 /* Check first fragment is the start of a deliverable packet */
1223 qent = TAILQ_FIRST(&priv->frags);
1224 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1225 return (0);
1226
1227 /* Check that all the fragments are there */
1228 while (!qent->last) {
1229 qnext = TAILQ_NEXT(qent, f_qent);
1230 if (qnext == NULL) /* end of queue */
1231 return (0);
1232 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq))
1233 return (0);
1234 qent = qnext;
1235 }
1236
1237 /* Got one */
1238 return (1);
1239}
1240
1241/*
1242 * Pull a completed packet off the head of the incoming fragment queue.
1243 * This assumes there is a completed packet there to pull off.
1244 */
1245static void
1246ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1247{
1248 const priv_p priv = NG_NODE_PRIVATE(node);
1249 struct ng_ppp_frag *qent, *qnext;
1250 struct mbuf *m = NULL, *tail;
1251
1252 qent = TAILQ_FIRST(&priv->frags);
1253 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first,
1254 ("%s: no packet", __func__));
1255 for (tail = NULL; qent != NULL; qent = qnext) {
1256 qnext = TAILQ_NEXT(qent, f_qent);
1257 KASSERT(!TAILQ_EMPTY(&priv->frags),
1258 ("%s: empty q", __func__));
1259 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1260 if (tail == NULL) {
1261 tail = m = qent->data;
1262 *metap = qent->meta; /* inherit first frag's meta */
1263 } else {
1264 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1265 tail->m_next = qent->data;
1266 NG_FREE_META(qent->meta); /* drop other frags' metas */
1267 }
1268 while (tail->m_next != NULL)
1269 tail = tail->m_next;
1270 if (qent->last)
1271 qnext = NULL;
1272 FREE(qent, M_NETGRAPH_PPP);
1273 priv->qlen--;
1274 }
1275 *mp = m;
1276}
1277
1278/*
1279 * Trim fragments from the queue whose packets can never be completed.
1280 * This assumes a complete packet is NOT at the beginning of the queue.
1281 * Returns 1 if fragments were removed, zero otherwise.
1282 */
1283static int
1284ng_ppp_frag_trim(node_p node)
1285{
1286 const priv_p priv = NG_NODE_PRIVATE(node);
1287 struct ng_ppp_frag *qent, *qnext = NULL;
1288 int removed = 0;
1289
1290 /* Scan for "dead" fragments and remove them */
1291 while (1) {
1292 int dead = 0;
1293
1294 /* If queue is empty, we're done */
1295 if (TAILQ_EMPTY(&priv->frags))
1296 break;
1297
1298 /* Determine whether first fragment can ever be completed */
1299 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1300 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1301 break;
1302 qnext = TAILQ_NEXT(qent, f_qent);
1303 KASSERT(qnext != NULL,
1304 ("%s: last frag < MSEQ?", __func__));
1305 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)
1306 || qent->last || qnext->first) {
1307 dead = 1;
1308 break;
1309 }
1310 }
1311 if (!dead)
1312 break;
1313
1314 /* Remove fragment and all others in the same packet */
1315 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) {
1316 KASSERT(!TAILQ_EMPTY(&priv->frags),
1317 ("%s: empty q", __func__));
1318 priv->bundleStats.dropFragments++;
1319 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1320 NG_FREE_M(qent->data);
1321 NG_FREE_META(qent->meta);
1322 FREE(qent, M_NETGRAPH_PPP);
1323 priv->qlen--;
1324 removed = 1;
1325 }
1326 }
1327 return (removed);
1328}
1329
1330/*
1331 * Run the queue, restoring the queue invariants
1332 */
1333static int
1334ng_ppp_frag_process(node_p node)
1335{
1336 const priv_p priv = NG_NODE_PRIVATE(node);
1337 struct mbuf *m;
1338 meta_p meta;
1339 item_p item;
1340
1341 /* Deliver any deliverable packets */
1342 while (ng_ppp_check_packet(node)) {
1343 ng_ppp_get_packet(node, &m, &meta);
1344 item = ng_package_data(m, meta);
1345 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1346 }
1347
1348 /* Delete dead fragments and try again */
1349 if (ng_ppp_frag_trim(node)) {
1350 while (ng_ppp_check_packet(node)) {
1351 ng_ppp_get_packet(node, &m, &meta);
1352 item = ng_package_data(m, meta);
1353 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1354 }
1355 }
1356
1357 /* Check for stale fragments while we're here */
1358 ng_ppp_frag_checkstale(node);
1359
1360 /* Check queue length */
1361 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1362 struct ng_ppp_frag *qent;
1363 int i;
1364
1365 /* Get oldest fragment */
1366 KASSERT(!TAILQ_EMPTY(&priv->frags),
1367 ("%s: empty q", __func__));
1368 qent = TAILQ_FIRST(&priv->frags);
1369
1370 /* Bump MSEQ if necessary */
1371 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1372 priv->mseq = qent->seq;
1373 for (i = 0; i < priv->numActiveLinks; i++) {
1374 struct ng_ppp_link *const alink =
1375 &priv->links[priv->activeLinks[i]];
1376
1377 if (MP_RECV_SEQ_DIFF(priv,
1378 alink->seq, priv->mseq) < 0)
1379 alink->seq = priv->mseq;
1380 }
1381 }
1382
1383 /* Drop it */
1384 priv->bundleStats.dropFragments++;
1385 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1386 NG_FREE_M(qent->data);
1387 NG_FREE_META(qent->meta);
1388 FREE(qent, M_NETGRAPH_PPP);
1389 priv->qlen--;
1390
1391 /* Process queue again */
1392 return ng_ppp_frag_process(node);
1393 }
1394
1395 /* Done */
1396 return (0);
1397}
1398
1399/*
1400 * Check for 'stale' completed packets that need to be delivered
1401 *
1402 * If a link goes down or has a temporary failure, MSEQ can get
1403 * "stuck", because no new incoming fragments appear on that link.
1404 * This can cause completed packets to never get delivered if
1405 * their sequence numbers are all > MSEQ + 1.
1406 *
1407 * This routine checks how long all of the completed packets have
1408 * been sitting in the queue, and if too long, removes fragments
1409 * from the queue and increments MSEQ to allow them to be delivered.
1410 */
1411static void
1412ng_ppp_frag_checkstale(node_p node)
1413{
1414 const priv_p priv = NG_NODE_PRIVATE(node);
1415 struct ng_ppp_frag *qent, *beg, *end;
1416 struct timeval now, age;
1417 struct mbuf *m;
1418 meta_p meta;
1419 int i, seq;
1420 item_p item;
1421
1422 now.tv_sec = 0; /* uninitialized state */
1423 while (1) {
1424
1425 /* If queue is empty, we're done */
1426 if (TAILQ_EMPTY(&priv->frags))
1427 break;
1428
1429 /* Find the first complete packet in the queue */
1430 beg = end = NULL;
1431 seq = TAILQ_FIRST(&priv->frags)->seq;
1432 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1433 if (qent->first)
1434 beg = qent;
1435 else if (qent->seq != seq)
1436 beg = NULL;
1437 if (beg != NULL && qent->last) {
1438 end = qent;
1439 break;
1440 }
1441 seq = MP_NEXT_RECV_SEQ(priv, seq);
1442 }
1443
1444 /* If none found, exit */
1445 if (end == NULL)
1446 break;
1447
1448 /* Get current time (we assume we've been up for >= 1 second) */
1449 if (now.tv_sec == 0)
1450 getmicrouptime(&now);
1451
1452 /* Check if packet has been queued too long */
1453 age = now;
1454 timevalsub(&age, &beg->timestamp);
1455 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1456 break;
1457
1458 /* Throw away junk fragments in front of the completed packet */
1459 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) {
1460 KASSERT(!TAILQ_EMPTY(&priv->frags),
1461 ("%s: empty q", __func__));
1462 priv->bundleStats.dropFragments++;
1463 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1464 NG_FREE_M(qent->data);
1465 NG_FREE_META(qent->meta);
1466 FREE(qent, M_NETGRAPH_PPP);
1467 priv->qlen--;
1468 }
1469
1470 /* Extract completed packet */
1471 ng_ppp_get_packet(node, &m, &meta);
1472
1473 /* Bump MSEQ if necessary */
1474 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) {
1475 priv->mseq = end->seq;
1476 for (i = 0; i < priv->numActiveLinks; i++) {
1477 struct ng_ppp_link *const alink =
1478 &priv->links[priv->activeLinks[i]];
1479
1480 if (MP_RECV_SEQ_DIFF(priv,
1481 alink->seq, priv->mseq) < 0)
1482 alink->seq = priv->mseq;
1483 }
1484 }
1485
1486 /* Deliver packet */
1487 item = ng_package_data(m, meta);
1488 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1489 }
1490}
1491
1492/*
1493 * Periodically call ng_ppp_frag_checkstale()
1494 */
1495static void
1496ng_ppp_frag_timeout(void *arg)
1497{
1498 const node_p node = arg;
1499 const priv_p priv = NG_NODE_PRIVATE(node);
1500 int s = splnet();
1501
1502 /* Handle the race where shutdown happens just before splnet() above */
1503 if (NG_NODE_NOT_VALID(node)) {
1504 NG_NODE_UNREF(node);
1505 splx(s);
1506 return;
1507 }
1508
1509 /* Reset timer state after timeout */
1510 KASSERT(priv->timerActive, ("%s: !timerActive", __func__));
1511 priv->timerActive = 0;
1512 KASSERT(node->nd_refs > 1, ("%s: nd_refs=%d", __func__, node->nd_refs));
1513 NG_NODE_UNREF(node);
1514
1515 /* Start timer again */
1516 ng_ppp_start_frag_timer(node);
1517
1518 /* Scan the fragment queue */
1519 ng_ppp_frag_checkstale(node);
1520 splx(s);
1521}
1522
1523/*
1524 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1525 * the frame across the individual PPP links and do so.
1526 */
1527static int
1528ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1529{
1530 const priv_p priv = NG_NODE_PRIVATE(node);
1531 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4;
1532 int distrib[NG_PPP_MAX_LINKS];
1533 int firstFragment;
1534 int activeLinkNum;
1535 item_p item;
1536
1537 /* At least one link must be active */
1538 if (priv->numActiveLinks == 0) {
1539 NG_FREE_M(m);
1540 NG_FREE_META(meta);
1541 return (ENETDOWN);
1542 }
1543
1544 /* Round-robin strategy */
1545 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1546 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1547 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1548 distrib[activeLinkNum] = m->m_pkthdr.len;
1549 goto deliver;
1550 }
1551
1552 /* Strategy when all links are equivalent (optimize the common case) */
1553 if (priv->allLinksEqual) {
1554 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1555 int i, remain;
1556
1557 for (i = 0; i < priv->numActiveLinks; i++)
1558 distrib[priv->lastLink++ % priv->numActiveLinks]
1559 = fraction;
1560 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1561 while (remain > 0) {
1562 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1563 remain--;
1564 }
1565 goto deliver;
1566 }
1567
1568 /* Strategy when all links are not equivalent */
1569 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1570
1571deliver:
1572 /* Update stats */
1573 priv->bundleStats.xmitFrames++;
1574 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1575
1576 /* Send alloted portions of frame out on the link(s) */
1577 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1578 activeLinkNum >= 0; activeLinkNum--) {
1579 const int linkNum = priv->activeLinks[activeLinkNum];
1580 struct ng_ppp_link *const link = &priv->links[linkNum];
1581
1582 /* Deliver fragment(s) out the next link */
1583 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1584 int len, lastFragment, error;
1585 struct mbuf *m2;
1586 meta_p meta2;
1587
1588 /* Calculate fragment length; don't exceed link MTU */
1589 len = distrib[activeLinkNum];
1590 if (len > link->conf.mru - hdr_len)
1591 len = link->conf.mru - hdr_len;
1592 distrib[activeLinkNum] -= len;
1593 lastFragment = (len == m->m_pkthdr.len);
1594
1595 /* Split off next fragment as "m2" */
1596 m2 = m;
1597 if (!lastFragment) {
| 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/ctype.h>
55
56#include <machine/limits.h>
57
58#include <netgraph/ng_message.h>
59#include <netgraph/netgraph.h>
60#include <netgraph/ng_parse.h>
61#include <netgraph/ng_ppp.h>
62#include <netgraph/ng_vjc.h>
63
64#ifdef NG_SEPARATE_MALLOC
65MALLOC_DEFINE(M_NETGRAPH_PPP, "netgraph_ppp", "netgraph ppp node");
66#else
67#define M_NETGRAPH_PPP M_NETGRAPH
68#endif
69
70#define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
71#define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
72
73/* Some PPP protocol numbers we're interested in */
74#define PROT_APPLETALK 0x0029
75#define PROT_COMPD 0x00fd
76#define PROT_CRYPTD 0x0053
77#define PROT_IP 0x0021
78#define PROT_IPV6 0x0057
79#define PROT_IPX 0x002b
80#define PROT_LCP 0xc021
81#define PROT_MP 0x003d
82#define PROT_VJCOMP 0x002d
83#define PROT_VJUNCOMP 0x002f
84
85/* Multilink PPP definitions */
86#define MP_MIN_MRRU 1500 /* per RFC 1990 */
87#define MP_INITIAL_SEQ 0 /* per RFC 1990 */
88#define MP_MIN_LINK_MRU 32
89
90#define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
91#define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
92#define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
93#define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
94
95#define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
96#define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
97#define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
98#define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
99
100#define MP_NOSEQ 0x7fffffff /* impossible sequence number */
101
102/* Sign extension of MP sequence numbers */
103#define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
104 ((s) | ~MP_SHORT_SEQ_MASK) \
105 : ((s) & MP_SHORT_SEQ_MASK))
106#define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
107 ((s) | ~MP_LONG_SEQ_MASK) \
108 : ((s) & MP_LONG_SEQ_MASK))
109
110/* Comparision of MP sequence numbers. Note: all sequence numbers
111 except priv->xseq are stored with the sign bit extended. */
112#define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y))
113#define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y))
114
115#define MP_RECV_SEQ_DIFF(priv,x,y) \
116 ((priv)->conf.recvShortSeq ? \
117 MP_SHORT_SEQ_DIFF((x), (y)) : \
118 MP_LONG_SEQ_DIFF((x), (y)))
119
120/* Increment receive sequence number */
121#define MP_NEXT_RECV_SEQ(priv,seq) \
122 ((priv)->conf.recvShortSeq ? \
123 MP_SHORT_EXTEND((seq) + 1) : \
124 MP_LONG_EXTEND((seq) + 1))
125
126/* Don't fragment transmitted packets smaller than this */
127#define MP_MIN_FRAG_LEN 6
128
129/* Maximum fragment reasssembly queue length */
130#define MP_MAX_QUEUE_LEN 128
131
132/* Fragment queue scanner period */
133#define MP_FRAGTIMER_INTERVAL (hz/2)
134
135/* We store incoming fragments this way */
136struct ng_ppp_frag {
137 int seq; /* fragment seq# */
138 u_char first; /* First in packet? */
139 u_char last; /* Last in packet? */
140 struct timeval timestamp; /* time of reception */
141 struct mbuf *data; /* Fragment data */
142 meta_p meta; /* Fragment meta */
143 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
144};
145
146/* We use integer indicies to refer to the non-link hooks */
147static const char *const ng_ppp_hook_names[] = {
148 NG_PPP_HOOK_ATALK,
149#define HOOK_INDEX_ATALK 0
150 NG_PPP_HOOK_BYPASS,
151#define HOOK_INDEX_BYPASS 1
152 NG_PPP_HOOK_COMPRESS,
153#define HOOK_INDEX_COMPRESS 2
154 NG_PPP_HOOK_ENCRYPT,
155#define HOOK_INDEX_ENCRYPT 3
156 NG_PPP_HOOK_DECOMPRESS,
157#define HOOK_INDEX_DECOMPRESS 4
158 NG_PPP_HOOK_DECRYPT,
159#define HOOK_INDEX_DECRYPT 5
160 NG_PPP_HOOK_INET,
161#define HOOK_INDEX_INET 6
162 NG_PPP_HOOK_IPX,
163#define HOOK_INDEX_IPX 7
164 NG_PPP_HOOK_VJC_COMP,
165#define HOOK_INDEX_VJC_COMP 8
166 NG_PPP_HOOK_VJC_IP,
167#define HOOK_INDEX_VJC_IP 9
168 NG_PPP_HOOK_VJC_UNCOMP,
169#define HOOK_INDEX_VJC_UNCOMP 10
170 NG_PPP_HOOK_VJC_VJIP,
171#define HOOK_INDEX_VJC_VJIP 11
172 NG_PPP_HOOK_IPV6,
173#define HOOK_INDEX_IPV6 12
174 NULL
175#define HOOK_INDEX_MAX 13
176};
177
178/* We store index numbers in the hook private pointer. The HOOK_INDEX()
179 for a hook is either the index (above) for normal hooks, or the ones
180 complement of the link number for link hooks.
181XXX Not any more.. (what a hack)
182#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
183*/
184
185/* Per-link private information */
186struct ng_ppp_link {
187 struct ng_ppp_link_conf conf; /* link configuration */
188 hook_p hook; /* connection to link data */
189 int32_t seq; /* highest rec'd seq# - MSEQ */
190 struct timeval lastWrite; /* time of last write */
191 int bytesInQueue; /* bytes in the output queue */
192 struct ng_ppp_link_stat stats; /* Link stats */
193};
194
195/* Total per-node private information */
196struct ng_ppp_private {
197 struct ng_ppp_bund_conf conf; /* bundle config */
198 struct ng_ppp_link_stat bundleStats; /* bundle stats */
199 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
200 int32_t xseq; /* next out MP seq # */
201 int32_t mseq; /* min links[i].seq */
202 u_char vjCompHooked; /* VJ comp hooked up? */
203 u_char allLinksEqual; /* all xmit the same? */
204 u_char timerActive; /* frag timer active? */
205 u_int numActiveLinks; /* how many links up */
206 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
207 u_int lastLink; /* for round robin */
208 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
209 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
210 frags;
211 int qlen; /* fraq queue length */
212 struct callout_handle fragTimer; /* fraq queue check */
213};
214typedef struct ng_ppp_private *priv_p;
215
216/* Netgraph node methods */
217static ng_constructor_t ng_ppp_constructor;
218static ng_rcvmsg_t ng_ppp_rcvmsg;
219static ng_shutdown_t ng_ppp_shutdown;
220static ng_newhook_t ng_ppp_newhook;
221static ng_rcvdata_t ng_ppp_rcvdata;
222static ng_disconnect_t ng_ppp_disconnect;
223
224/* Helper functions */
225static int ng_ppp_input(node_p node, int bypass,
226 int linkNum, item_p item);
227static int ng_ppp_output(node_p node, int bypass, int proto,
228 int linkNum, item_p item);
229static int ng_ppp_mp_input(node_p node, int linkNum, item_p item);
230static int ng_ppp_check_packet(node_p node);
231static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
232static int ng_ppp_frag_process(node_p node);
233static int ng_ppp_frag_trim(node_p node);
234static void ng_ppp_frag_timeout(void *arg);
235static void ng_ppp_frag_checkstale(node_p node);
236static void ng_ppp_frag_reset(node_p node);
237static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
238static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
239static int ng_ppp_intcmp(const void *v1, const void *v2);
240static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
241static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
242static int ng_ppp_config_valid(node_p node,
243 const struct ng_ppp_node_conf *newConf);
244static void ng_ppp_update(node_p node, int newConf);
245static void ng_ppp_start_frag_timer(node_p node);
246static void ng_ppp_stop_frag_timer(node_p node);
247
248/* Parse type for struct ng_ppp_mp_state_type */
249static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = {
250 &ng_parse_hint32_type,
251 NG_PPP_MAX_LINKS
252};
253static const struct ng_parse_type ng_ppp_rseq_array_type = {
254 &ng_parse_fixedarray_type,
255 &ng_ppp_rseq_array_info,
256};
257static const struct ng_parse_struct_field ng_ppp_mp_state_type_fields[]
258 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type);
259static const struct ng_parse_type ng_ppp_mp_state_type = {
260 &ng_parse_struct_type,
261 &ng_ppp_mp_state_type_fields
262};
263
264/* Parse type for struct ng_ppp_link_conf */
265static const struct ng_parse_struct_field ng_ppp_link_type_fields[]
266 = NG_PPP_LINK_TYPE_INFO;
267static const struct ng_parse_type ng_ppp_link_type = {
268 &ng_parse_struct_type,
269 &ng_ppp_link_type_fields
270};
271
272/* Parse type for struct ng_ppp_bund_conf */
273static const struct ng_parse_struct_field ng_ppp_bund_type_fields[]
274 = NG_PPP_BUND_TYPE_INFO;
275static const struct ng_parse_type ng_ppp_bund_type = {
276 &ng_parse_struct_type,
277 &ng_ppp_bund_type_fields
278};
279
280/* Parse type for struct ng_ppp_node_conf */
281static const struct ng_parse_fixedarray_info ng_ppp_array_info = {
282 &ng_ppp_link_type,
283 NG_PPP_MAX_LINKS
284};
285static const struct ng_parse_type ng_ppp_link_array_type = {
286 &ng_parse_fixedarray_type,
287 &ng_ppp_array_info,
288};
289static const struct ng_parse_struct_field ng_ppp_conf_type_fields[]
290 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
291static const struct ng_parse_type ng_ppp_conf_type = {
292 &ng_parse_struct_type,
293 &ng_ppp_conf_type_fields
294};
295
296/* Parse type for struct ng_ppp_link_stat */
297static const struct ng_parse_struct_field ng_ppp_stats_type_fields[]
298 = NG_PPP_STATS_TYPE_INFO;
299static const struct ng_parse_type ng_ppp_stats_type = {
300 &ng_parse_struct_type,
301 &ng_ppp_stats_type_fields
302};
303
304/* List of commands and how to convert arguments to/from ASCII */
305static const struct ng_cmdlist ng_ppp_cmds[] = {
306 {
307 NGM_PPP_COOKIE,
308 NGM_PPP_SET_CONFIG,
309 "setconfig",
310 &ng_ppp_conf_type,
311 NULL
312 },
313 {
314 NGM_PPP_COOKIE,
315 NGM_PPP_GET_CONFIG,
316 "getconfig",
317 NULL,
318 &ng_ppp_conf_type
319 },
320 {
321 NGM_PPP_COOKIE,
322 NGM_PPP_GET_MP_STATE,
323 "getmpstate",
324 NULL,
325 &ng_ppp_mp_state_type
326 },
327 {
328 NGM_PPP_COOKIE,
329 NGM_PPP_GET_LINK_STATS,
330 "getstats",
331 &ng_parse_int16_type,
332 &ng_ppp_stats_type
333 },
334 {
335 NGM_PPP_COOKIE,
336 NGM_PPP_CLR_LINK_STATS,
337 "clrstats",
338 &ng_parse_int16_type,
339 NULL
340 },
341 {
342 NGM_PPP_COOKIE,
343 NGM_PPP_GETCLR_LINK_STATS,
344 "getclrstats",
345 &ng_parse_int16_type,
346 &ng_ppp_stats_type
347 },
348 { 0 }
349};
350
351/* Node type descriptor */
352static struct ng_type ng_ppp_typestruct = {
353 NG_ABI_VERSION,
354 NG_PPP_NODE_TYPE,
355 NULL,
356 ng_ppp_constructor,
357 ng_ppp_rcvmsg,
358 ng_ppp_shutdown,
359 ng_ppp_newhook,
360 NULL,
361 NULL,
362 ng_ppp_rcvdata,
363 ng_ppp_disconnect,
364 ng_ppp_cmds
365};
366NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
367
368static int *compareLatencies; /* hack for ng_ppp_intcmp() */
369
370/* Address and control field header */
371static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
372
373/* Maximum time we'll let a complete incoming packet sit in the queue */
374static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
375
376#define ERROUT(x) do { error = (x); goto done; } while (0)
377
378/************************************************************************
379 NETGRAPH NODE STUFF
380 ************************************************************************/
381
382/*
383 * Node type constructor
384 */
385static int
386ng_ppp_constructor(node_p node)
387{
388 priv_p priv;
389 int i;
390
391 /* Allocate private structure */
392 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_PPP, M_NOWAIT | M_ZERO);
393 if (priv == NULL)
394 return (ENOMEM);
395
396 NG_NODE_SET_PRIVATE(node, priv);
397
398 /* Initialize state */
399 TAILQ_INIT(&priv->frags);
400 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
401 priv->links[i].seq = MP_NOSEQ;
402 callout_handle_init(&priv->fragTimer);
403
404 /* Done */
405 return (0);
406}
407
408/*
409 * Give our OK for a hook to be added
410 */
411static int
412ng_ppp_newhook(node_p node, hook_p hook, const char *name)
413{
414 const priv_p priv = NG_NODE_PRIVATE(node);
415 int linkNum = -1;
416 hook_p *hookPtr = NULL;
417 int hookIndex = -1;
418
419 /* Figure out which hook it is */
420 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
421 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
422 const char *cp;
423 char *eptr;
424
425 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
426 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
427 return (EINVAL);
428 linkNum = (int)strtoul(cp, &eptr, 10);
429 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
430 return (EINVAL);
431 hookPtr = &priv->links[linkNum].hook;
432 hookIndex = ~linkNum;
433 } else { /* must be a non-link hook */
434 int i;
435
436 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
437 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
438 hookPtr = &priv->hooks[i];
439 hookIndex = i;
440 break;
441 }
442 }
443 if (ng_ppp_hook_names[i] == NULL)
444 return (EINVAL); /* no such hook */
445 }
446
447 /* See if hook is already connected */
448 if (*hookPtr != NULL)
449 return (EISCONN);
450
451 /* Disallow more than one link unless multilink is enabled */
452 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
453 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
454 return (ENODEV);
455
456 /* OK */
457 *hookPtr = hook;
458 NG_HOOK_SET_PRIVATE(hook, (void *)(intptr_t)hookIndex);
459 ng_ppp_update(node, 0);
460 return (0);
461}
462
463/*
464 * Receive a control message
465 */
466static int
467ng_ppp_rcvmsg(node_p node, item_p item, hook_p lasthook)
468{
469 const priv_p priv = NG_NODE_PRIVATE(node);
470 struct ng_mesg *resp = NULL;
471 int error = 0;
472 struct ng_mesg *msg;
473
474 NGI_GET_MSG(item, msg);
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 /*
563 * Forward it to the vjc node. leave the
564 * old return address alone.
565 * If we have no hook, let NG_RESPOND_MSG
566 * clean up any remaining resources.
567 * Because we have no resp, the item will be freed
568 * along with anything it references. Don't
569 * let msg be freed twice.
570 */
571 NGI_MSG(item) = msg; /* put it back in the item */
572 msg = NULL;
573 if ((lasthook = priv->links[HOOK_INDEX_VJC_IP].hook)) {
574 NG_FWD_ITEM_HOOK(error, item, lasthook);
575 }
576 return (error);
577 }
578 default:
579 error = EINVAL;
580 break;
581 }
582done:
583 NG_RESPOND_MSG(error, node, item, resp);
584 NG_FREE_MSG(msg);
585 return (error);
586}
587
588/*
589 * Receive data on a hook
590 */
591static int
592ng_ppp_rcvdata(hook_p hook, item_p item)
593{
594 const node_p node = NG_HOOK_NODE(hook);
595 const priv_p priv = NG_NODE_PRIVATE(node);
596 const int index = (intptr_t)NG_HOOK_PRIVATE(hook);
597 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
598 hook_p outHook = NULL;
599 int proto = 0, error;
600 struct mbuf *m;
601
602 NGI_GET_M(item, m);
603 /* Did it come from a link hook? */
604 if (index < 0) {
605 struct ng_ppp_link *link;
606
607 /* Convert index into a link number */
608 linkNum = (u_int16_t)~index;
609 KASSERT(linkNum < NG_PPP_MAX_LINKS,
610 ("%s: bogus index 0x%x", __func__, index));
611 link = &priv->links[linkNum];
612
613 /* Stats */
614 link->stats.recvFrames++;
615 link->stats.recvOctets += m->m_pkthdr.len;
616
617 /* Strip address and control fields, if present */
618 if (m->m_pkthdr.len >= 2) {
619 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
620 NG_FREE_ITEM(item);
621 return (ENOBUFS);
622 }
623 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
624 m_adj(m, 2);
625 }
626
627 /* Dispatch incoming frame (if not enabled, to bypass) */
628 NGI_M(item) = m; /* put changed m back in item */
629 return ng_ppp_input(node,
630 !link->conf.enableLink, linkNum, item);
631 }
632
633 /* Get protocol & check if data allowed from this hook */
634 NGI_M(item) = m; /* put possibly changed m back in item */
635 switch (index) {
636
637 /* Outgoing data */
638 case HOOK_INDEX_ATALK:
639 if (!priv->conf.enableAtalk) {
640 NG_FREE_ITEM(item);
641 return (ENXIO);
642 }
643 proto = PROT_APPLETALK;
644 break;
645 case HOOK_INDEX_IPX:
646 if (!priv->conf.enableIPX) {
647 NG_FREE_ITEM(item);
648 return (ENXIO);
649 }
650 proto = PROT_IPX;
651 break;
652 case HOOK_INDEX_IPV6:
653 if (!priv->conf.enableIPv6) {
654 NG_FREE_ITEM(item);
655 return (ENXIO);
656 }
657 proto = PROT_IPV6;
658 break;
659 case HOOK_INDEX_INET:
660 case HOOK_INDEX_VJC_VJIP:
661 if (!priv->conf.enableIP) {
662 NG_FREE_ITEM(item);
663 return (ENXIO);
664 }
665 proto = PROT_IP;
666 break;
667 case HOOK_INDEX_VJC_COMP:
668 if (!priv->conf.enableVJCompression) {
669 NG_FREE_ITEM(item);
670 return (ENXIO);
671 }
672 proto = PROT_VJCOMP;
673 break;
674 case HOOK_INDEX_VJC_UNCOMP:
675 if (!priv->conf.enableVJCompression) {
676 NG_FREE_ITEM(item);
677 return (ENXIO);
678 }
679 proto = PROT_VJUNCOMP;
680 break;
681 case HOOK_INDEX_COMPRESS:
682 if (!priv->conf.enableCompression) {
683 NG_FREE_ITEM(item);
684 return (ENXIO);
685 }
686 proto = PROT_COMPD;
687 break;
688 case HOOK_INDEX_ENCRYPT:
689 if (!priv->conf.enableEncryption) {
690 NG_FREE_ITEM(item);
691 return (ENXIO);
692 }
693 proto = PROT_CRYPTD;
694 break;
695 case HOOK_INDEX_BYPASS:
696 if (m->m_pkthdr.len < 4) {
697 NG_FREE_ITEM(item);
698 return (EINVAL);
699 }
700 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
701 NGI_M(item) = NULL; /* don't free twice */
702 NG_FREE_ITEM(item);
703 return (ENOBUFS);
704 }
705 NGI_M(item) = m; /* m may have changed */
706 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
707 proto = ntohs(mtod(m, u_int16_t *)[1]);
708 m_adj(m, 4);
709 if (linkNum >= NG_PPP_MAX_LINKS
710 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
711 NG_FREE_ITEM(item);
712 return (EINVAL);
713 }
714 break;
715
716 /* Incoming data */
717 case HOOK_INDEX_VJC_IP:
718 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
719 NG_FREE_ITEM(item);
720 return (ENXIO);
721 }
722 break;
723 case HOOK_INDEX_DECOMPRESS:
724 if (!priv->conf.enableDecompression) {
725 NG_FREE_ITEM(item);
726 return (ENXIO);
727 }
728 break;
729 case HOOK_INDEX_DECRYPT:
730 if (!priv->conf.enableDecryption) {
731 NG_FREE_ITEM(item);
732 return (ENXIO);
733 }
734 break;
735 default:
736 panic("%s: bogus index 0x%x", __func__, index);
737 }
738
739 /* Now figure out what to do with the frame */
740 switch (index) {
741
742 /* Outgoing data */
743 case HOOK_INDEX_INET:
744 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
745 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
746 break;
747 }
748 /* FALLTHROUGH */
749 case HOOK_INDEX_ATALK:
750 case HOOK_INDEX_IPV6:
751 case HOOK_INDEX_IPX:
752 case HOOK_INDEX_VJC_COMP:
753 case HOOK_INDEX_VJC_UNCOMP:
754 case HOOK_INDEX_VJC_VJIP:
755 if (priv->conf.enableCompression
756 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
757 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
758 NGI_M(item) = NULL;
759 NG_FREE_ITEM(item);
760 return (ENOBUFS);
761 }
762 NGI_M(item) = m; /* m may have changed */
763 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
764 break;
765 }
766 /* FALLTHROUGH */
767 case HOOK_INDEX_COMPRESS:
768 if (priv->conf.enableEncryption
769 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
770 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
771 NGI_M(item) = NULL;
772 NG_FREE_ITEM(item);
773 return (ENOBUFS);
774 }
775 NGI_M(item) = m; /* m may have changed */
776 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
777 break;
778 }
779 /* FALLTHROUGH */
780 case HOOK_INDEX_ENCRYPT:
781 return ng_ppp_output(node, 0, proto, NG_PPP_BUNDLE_LINKNUM, item);
782
783 case HOOK_INDEX_BYPASS:
784 return ng_ppp_output(node, 1, proto, linkNum, item);
785
786 /* Incoming data */
787 case HOOK_INDEX_DECRYPT:
788 case HOOK_INDEX_DECOMPRESS:
789 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
790
791 case HOOK_INDEX_VJC_IP:
792 outHook = priv->hooks[HOOK_INDEX_INET];
793 break;
794 }
795
796 /* Send packet out hook */
797 NG_FWD_ITEM_HOOK(error, item, outHook);
798 return (error);
799}
800
801/*
802 * Destroy node
803 */
804static int
805ng_ppp_shutdown(node_p node)
806{
807 const priv_p priv = NG_NODE_PRIVATE(node);
808
809 /* Stop fragment queue timer */
810 ng_ppp_stop_frag_timer(node);
811
812 /* Take down netgraph node */
813 ng_ppp_frag_reset(node);
814 bzero(priv, sizeof(*priv));
815 FREE(priv, M_NETGRAPH_PPP);
816 NG_NODE_SET_PRIVATE(node, NULL);
817 NG_NODE_UNREF(node); /* let the node escape */
818 return (0);
819}
820
821/*
822 * Hook disconnection
823 */
824static int
825ng_ppp_disconnect(hook_p hook)
826{
827 const node_p node = NG_HOOK_NODE(hook);
828 const priv_p priv = NG_NODE_PRIVATE(node);
829 const int index = (intptr_t)NG_HOOK_PRIVATE(hook);
830
831 /* Zero out hook pointer */
832 if (index < 0)
833 priv->links[~index].hook = NULL;
834 else
835 priv->hooks[index] = NULL;
836
837 /* Update derived info (or go away if no hooks left) */
838 if (NG_NODE_NUMHOOKS(node) > 0) {
839 ng_ppp_update(node, 0);
840 } else {
841 if (NG_NODE_IS_VALID(node)) {
842 ng_rmnode_self(node);
843 }
844 }
845 return (0);
846}
847
848/************************************************************************
849 HELPER STUFF
850 ************************************************************************/
851
852/*
853 * Handle an incoming frame. Extract the PPP protocol number
854 * and dispatch accordingly.
855 */
856static int
857ng_ppp_input(node_p node, int bypass, int linkNum, item_p item)
858{
859 const priv_p priv = NG_NODE_PRIVATE(node);
860 hook_p outHook = NULL;
861 int proto, error;
862 struct mbuf *m;
863
864
865 NGI_GET_M(item, m);
866 /* Extract protocol number */
867 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
868 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
869 NG_FREE_ITEM(item);
870 return (ENOBUFS);
871 }
872 proto = (proto << 8) + *mtod(m, u_char *);
873 m_adj(m, 1);
874 }
875 if (!PROT_VALID(proto)) {
876 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
877 priv->bundleStats.badProtos++;
878 else
879 priv->links[linkNum].stats.badProtos++;
880 NG_FREE_ITEM(item);
881 NG_FREE_M(m);
882 return (EINVAL);
883 }
884
885 /* Bypass frame? */
886 if (bypass)
887 goto bypass;
888
889 /* Check protocol */
890 switch (proto) {
891 case PROT_COMPD:
892 if (priv->conf.enableDecompression)
893 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
894 break;
895 case PROT_CRYPTD:
896 if (priv->conf.enableDecryption)
897 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
898 break;
899 case PROT_VJCOMP:
900 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
901 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
902 break;
903 case PROT_VJUNCOMP:
904 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
905 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
906 break;
907 case PROT_MP:
908 if (priv->conf.enableMultilink
909 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
910 NGI_M(item) = m;
911 return ng_ppp_mp_input(node, linkNum, item);
912 }
913 break;
914 case PROT_APPLETALK:
915 if (priv->conf.enableAtalk)
916 outHook = priv->hooks[HOOK_INDEX_ATALK];
917 break;
918 case PROT_IPX:
919 if (priv->conf.enableIPX)
920 outHook = priv->hooks[HOOK_INDEX_IPX];
921 break;
922 case PROT_IP:
923 if (priv->conf.enableIP)
924 outHook = priv->hooks[HOOK_INDEX_INET];
925 break;
926 case PROT_IPV6:
927 if (priv->conf.enableIPv6)
928 outHook = priv->hooks[HOOK_INDEX_IPV6];
929 break;
930 }
931
932bypass:
933 /* For unknown/inactive protocols, forward out the bypass hook */
934 if (outHook == NULL) {
935 u_int16_t hdr[2];
936
937 hdr[0] = htons(linkNum);
938 hdr[1] = htons((u_int16_t)proto);
939 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
940 NG_FREE_ITEM(item);
941 return (ENOBUFS);
942 }
943 outHook = priv->hooks[HOOK_INDEX_BYPASS];
944 }
945
946 /* Forward frame */
947 NG_FWD_NEW_DATA(error, item, outHook, m);
948 return (error);
949}
950
951/*
952 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM.
953 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
954 *
955 * If the frame is too big for the particular link, return EMSGSIZE.
956 */
957static int
958ng_ppp_output(node_p node, int bypass,
959 int proto, int linkNum, item_p item)
960{
961 const priv_p priv = NG_NODE_PRIVATE(node);
962 struct ng_ppp_link *link;
963 int len, error;
964 struct mbuf *m;
965 u_int16_t mru;
966
967 /* Extract mbuf */
968 NGI_GET_M(item, m);
969
970 /* If not doing MP, map bundle virtual link to (the only) link */
971 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
972 linkNum = priv->activeLinks[0];
973
974 /* Get link pointer (optimization) */
975 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
976 &priv->links[linkNum] : NULL;
977
978 /* Check link status (if real) */
979 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
980 if (!bypass && !link->conf.enableLink) {
981 NG_FREE_M(m);
982 NG_FREE_ITEM(item);
983 return (ENXIO);
984 }
985 if (link->hook == NULL) {
986 NG_FREE_M(m);
987 NG_FREE_ITEM(item);
988 return (ENETDOWN);
989 }
990 }
991
992 /* Check peer's MRU for this link */
993 mru = (link != NULL) ? link->conf.mru : priv->conf.mrru;
994 if (mru != 0 && m->m_pkthdr.len > mru) {
995 NG_FREE_M(m);
996 NG_FREE_ITEM(item);
997 return (EMSGSIZE);
998 }
999
1000 /* Prepend protocol number, possibly compressed */
1001 if ((m = ng_ppp_addproto(m, proto,
1002 linkNum == NG_PPP_BUNDLE_LINKNUM
1003 || link->conf.enableProtoComp)) == NULL) {
1004 NG_FREE_ITEM(item);
1005 return (ENOBUFS);
1006 }
1007
1008 /* Special handling for the MP virtual link */
1009 if (linkNum == NG_PPP_BUNDLE_LINKNUM) {
1010 meta_p meta;
1011
1012 /* strip off and discard the queue item */
1013 NGI_GET_META(item, meta);
1014 NG_FREE_ITEM(item);
1015 return ng_ppp_mp_output(node, m, meta);
1016 }
1017
1018 /* Prepend address and control field (unless compressed) */
1019 if (proto == PROT_LCP || !link->conf.enableACFComp) {
1020 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
1021 NG_FREE_ITEM(item);
1022 return (ENOBUFS);
1023 }
1024 }
1025
1026 /* Deliver frame */
1027 len = m->m_pkthdr.len;
1028 NG_FWD_NEW_DATA(error, item, link->hook, m);
1029
1030 /* Update stats and 'bytes in queue' counter */
1031 if (error == 0) {
1032 link->stats.xmitFrames++;
1033 link->stats.xmitOctets += len;
1034 link->bytesInQueue += len;
1035 getmicrouptime(&link->lastWrite);
1036 }
1037 return error;
1038}
1039
1040/*
1041 * Handle an incoming multi-link fragment
1042 *
1043 * The fragment reassembly algorithm is somewhat complex. This is mainly
1044 * because we are required not to reorder the reconstructed packets, yet
1045 * fragments are only guaranteed to arrive in order on a per-link basis.
1046 * In other words, when we have a complete packet ready, but the previous
1047 * packet is still incomplete, we have to decide between delivering the
1048 * complete packet and throwing away the incomplete one, or waiting to
1049 * see if the remainder of the incomplete one arrives, at which time we
1050 * can deliver both packets, in order.
1051 *
1052 * This problem is exacerbated by "sequence number slew", which is when
1053 * the sequence numbers coming in from different links are far apart from
1054 * each other. In particular, certain unnamed equipment (*cough* Ascend)
1055 * has been seen to generate sequence number slew of up to 10 on an ISDN
1056 * 2B-channel MP link. There is nothing invalid about sequence number slew
1057 * but it makes the reasssembly process have to work harder.
1058 *
1059 * However, the peer is required to transmit fragments in order on each
1060 * link. That means if we define MSEQ as the minimum over all links of
1061 * the highest sequence number received on that link, then we can always
1062 * give up any hope of receiving a fragment with sequence number < MSEQ in
1063 * the future (all of this using 'wraparound' sequence number space).
1064 * Therefore we can always immediately throw away incomplete packets
1065 * missing fragments with sequence numbers < MSEQ.
1066 *
1067 * Here is an overview of our algorithm:
1068 *
1069 * o Received fragments are inserted into a queue, for which we
1070 * maintain these invariants between calls to this function:
1071 *
1072 * - Fragments are ordered in the queue by sequence number
1073 * - If a complete packet is at the head of the queue, then
1074 * the first fragment in the packet has seq# > MSEQ + 1
1075 * (otherwise, we could deliver it immediately)
1076 * - If any fragments have seq# < MSEQ, then they are necessarily
1077 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
1078 * we can throw them away because they'll never be completed)
1079 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
1080 *
1081 * o We have a periodic timer that checks the queue for the first
1082 * complete packet that has been sitting in the queue "too long".
1083 * When one is detected, all previous (incomplete) fragments are
1084 * discarded, their missing fragments are declared lost and MSEQ
1085 * is increased.
1086 *
1087 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1088 * because we've already delcared it lost.
1089 *
1090 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1091 */
1092static int
1093ng_ppp_mp_input(node_p node, int linkNum, item_p item)
1094{
1095 const priv_p priv = NG_NODE_PRIVATE(node);
1096 struct ng_ppp_link *const link = &priv->links[linkNum];
1097 struct ng_ppp_frag frag0, *frag = &frag0;
1098 struct ng_ppp_frag *qent;
1099 int i, diff, inserted;
1100 struct mbuf *m;
1101 meta_p meta;
1102
1103 NGI_GET_M(item, m);
1104 NGI_GET_META(item, meta);
1105 NG_FREE_ITEM(item);
1106 /* Stats */
1107 priv->bundleStats.recvFrames++;
1108 priv->bundleStats.recvOctets += m->m_pkthdr.len;
1109
1110 /* Extract fragment information from MP header */
1111 if (priv->conf.recvShortSeq) {
1112 u_int16_t shdr;
1113
1114 if (m->m_pkthdr.len < 2) {
1115 link->stats.runts++;
1116 NG_FREE_M(m);
1117 NG_FREE_META(meta);
1118 return (EINVAL);
1119 }
1120 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1121 NG_FREE_META(meta);
1122 return (ENOBUFS);
1123 }
1124 shdr = ntohs(*mtod(m, u_int16_t *));
1125 frag->seq = MP_SHORT_EXTEND(shdr);
1126 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1127 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1128 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1129 m_adj(m, 2);
1130 } else {
1131 u_int32_t lhdr;
1132
1133 if (m->m_pkthdr.len < 4) {
1134 link->stats.runts++;
1135 NG_FREE_M(m);
1136 NG_FREE_META(meta);
1137 return (EINVAL);
1138 }
1139 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1140 NG_FREE_META(meta);
1141 return (ENOBUFS);
1142 }
1143 lhdr = ntohl(*mtod(m, u_int32_t *));
1144 frag->seq = MP_LONG_EXTEND(lhdr);
1145 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1146 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1147 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1148 m_adj(m, 4);
1149 }
1150 frag->data = m;
1151 frag->meta = meta;
1152 getmicrouptime(&frag->timestamp);
1153
1154 /* If sequence number is < MSEQ, we've already declared this
1155 fragment as lost, so we have no choice now but to drop it */
1156 if (diff < 0) {
1157 link->stats.dropFragments++;
1158 NG_FREE_M(m);
1159 NG_FREE_META(meta);
1160 return (0);
1161 }
1162
1163 /* Update highest received sequence number on this link and MSEQ */
1164 priv->mseq = link->seq = frag->seq;
1165 for (i = 0; i < priv->numActiveLinks; i++) {
1166 struct ng_ppp_link *const alink =
1167 &priv->links[priv->activeLinks[i]];
1168
1169 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1170 priv->mseq = alink->seq;
1171 }
1172
1173 /* Allocate a new frag struct for the queue */
1174 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH_PPP, M_NOWAIT);
1175 if (frag == NULL) {
1176 NG_FREE_M(m);
1177 NG_FREE_META(meta);
1178 ng_ppp_frag_process(node);
1179 return (ENOMEM);
1180 }
1181 *frag = frag0;
1182
1183 /* Add fragment to queue, which is sorted by sequence number */
1184 inserted = 0;
1185 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) {
1186 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq);
1187 if (diff > 0) {
1188 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1189 inserted = 1;
1190 break;
1191 } else if (diff == 0) { /* should never happen! */
1192 link->stats.dupFragments++;
1193 NG_FREE_M(frag->data);
1194 NG_FREE_META(frag->meta);
1195 FREE(frag, M_NETGRAPH_PPP);
1196 return (EINVAL);
1197 }
1198 }
1199 if (!inserted)
1200 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1201 priv->qlen++;
1202
1203 /* Process the queue */
1204 return ng_ppp_frag_process(node);
1205}
1206
1207/*
1208 * Examine our list of fragments, and determine if there is a
1209 * complete and deliverable packet at the head of the list.
1210 * Return 1 if so, zero otherwise.
1211 */
1212static int
1213ng_ppp_check_packet(node_p node)
1214{
1215 const priv_p priv = NG_NODE_PRIVATE(node);
1216 struct ng_ppp_frag *qent, *qnext;
1217
1218 /* Check for empty queue */
1219 if (TAILQ_EMPTY(&priv->frags))
1220 return (0);
1221
1222 /* Check first fragment is the start of a deliverable packet */
1223 qent = TAILQ_FIRST(&priv->frags);
1224 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1225 return (0);
1226
1227 /* Check that all the fragments are there */
1228 while (!qent->last) {
1229 qnext = TAILQ_NEXT(qent, f_qent);
1230 if (qnext == NULL) /* end of queue */
1231 return (0);
1232 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq))
1233 return (0);
1234 qent = qnext;
1235 }
1236
1237 /* Got one */
1238 return (1);
1239}
1240
1241/*
1242 * Pull a completed packet off the head of the incoming fragment queue.
1243 * This assumes there is a completed packet there to pull off.
1244 */
1245static void
1246ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1247{
1248 const priv_p priv = NG_NODE_PRIVATE(node);
1249 struct ng_ppp_frag *qent, *qnext;
1250 struct mbuf *m = NULL, *tail;
1251
1252 qent = TAILQ_FIRST(&priv->frags);
1253 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first,
1254 ("%s: no packet", __func__));
1255 for (tail = NULL; qent != NULL; qent = qnext) {
1256 qnext = TAILQ_NEXT(qent, f_qent);
1257 KASSERT(!TAILQ_EMPTY(&priv->frags),
1258 ("%s: empty q", __func__));
1259 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1260 if (tail == NULL) {
1261 tail = m = qent->data;
1262 *metap = qent->meta; /* inherit first frag's meta */
1263 } else {
1264 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1265 tail->m_next = qent->data;
1266 NG_FREE_META(qent->meta); /* drop other frags' metas */
1267 }
1268 while (tail->m_next != NULL)
1269 tail = tail->m_next;
1270 if (qent->last)
1271 qnext = NULL;
1272 FREE(qent, M_NETGRAPH_PPP);
1273 priv->qlen--;
1274 }
1275 *mp = m;
1276}
1277
1278/*
1279 * Trim fragments from the queue whose packets can never be completed.
1280 * This assumes a complete packet is NOT at the beginning of the queue.
1281 * Returns 1 if fragments were removed, zero otherwise.
1282 */
1283static int
1284ng_ppp_frag_trim(node_p node)
1285{
1286 const priv_p priv = NG_NODE_PRIVATE(node);
1287 struct ng_ppp_frag *qent, *qnext = NULL;
1288 int removed = 0;
1289
1290 /* Scan for "dead" fragments and remove them */
1291 while (1) {
1292 int dead = 0;
1293
1294 /* If queue is empty, we're done */
1295 if (TAILQ_EMPTY(&priv->frags))
1296 break;
1297
1298 /* Determine whether first fragment can ever be completed */
1299 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1300 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1301 break;
1302 qnext = TAILQ_NEXT(qent, f_qent);
1303 KASSERT(qnext != NULL,
1304 ("%s: last frag < MSEQ?", __func__));
1305 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)
1306 || qent->last || qnext->first) {
1307 dead = 1;
1308 break;
1309 }
1310 }
1311 if (!dead)
1312 break;
1313
1314 /* Remove fragment and all others in the same packet */
1315 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) {
1316 KASSERT(!TAILQ_EMPTY(&priv->frags),
1317 ("%s: empty q", __func__));
1318 priv->bundleStats.dropFragments++;
1319 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1320 NG_FREE_M(qent->data);
1321 NG_FREE_META(qent->meta);
1322 FREE(qent, M_NETGRAPH_PPP);
1323 priv->qlen--;
1324 removed = 1;
1325 }
1326 }
1327 return (removed);
1328}
1329
1330/*
1331 * Run the queue, restoring the queue invariants
1332 */
1333static int
1334ng_ppp_frag_process(node_p node)
1335{
1336 const priv_p priv = NG_NODE_PRIVATE(node);
1337 struct mbuf *m;
1338 meta_p meta;
1339 item_p item;
1340
1341 /* Deliver any deliverable packets */
1342 while (ng_ppp_check_packet(node)) {
1343 ng_ppp_get_packet(node, &m, &meta);
1344 item = ng_package_data(m, meta);
1345 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1346 }
1347
1348 /* Delete dead fragments and try again */
1349 if (ng_ppp_frag_trim(node)) {
1350 while (ng_ppp_check_packet(node)) {
1351 ng_ppp_get_packet(node, &m, &meta);
1352 item = ng_package_data(m, meta);
1353 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1354 }
1355 }
1356
1357 /* Check for stale fragments while we're here */
1358 ng_ppp_frag_checkstale(node);
1359
1360 /* Check queue length */
1361 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1362 struct ng_ppp_frag *qent;
1363 int i;
1364
1365 /* Get oldest fragment */
1366 KASSERT(!TAILQ_EMPTY(&priv->frags),
1367 ("%s: empty q", __func__));
1368 qent = TAILQ_FIRST(&priv->frags);
1369
1370 /* Bump MSEQ if necessary */
1371 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1372 priv->mseq = qent->seq;
1373 for (i = 0; i < priv->numActiveLinks; i++) {
1374 struct ng_ppp_link *const alink =
1375 &priv->links[priv->activeLinks[i]];
1376
1377 if (MP_RECV_SEQ_DIFF(priv,
1378 alink->seq, priv->mseq) < 0)
1379 alink->seq = priv->mseq;
1380 }
1381 }
1382
1383 /* Drop it */
1384 priv->bundleStats.dropFragments++;
1385 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1386 NG_FREE_M(qent->data);
1387 NG_FREE_META(qent->meta);
1388 FREE(qent, M_NETGRAPH_PPP);
1389 priv->qlen--;
1390
1391 /* Process queue again */
1392 return ng_ppp_frag_process(node);
1393 }
1394
1395 /* Done */
1396 return (0);
1397}
1398
1399/*
1400 * Check for 'stale' completed packets that need to be delivered
1401 *
1402 * If a link goes down or has a temporary failure, MSEQ can get
1403 * "stuck", because no new incoming fragments appear on that link.
1404 * This can cause completed packets to never get delivered if
1405 * their sequence numbers are all > MSEQ + 1.
1406 *
1407 * This routine checks how long all of the completed packets have
1408 * been sitting in the queue, and if too long, removes fragments
1409 * from the queue and increments MSEQ to allow them to be delivered.
1410 */
1411static void
1412ng_ppp_frag_checkstale(node_p node)
1413{
1414 const priv_p priv = NG_NODE_PRIVATE(node);
1415 struct ng_ppp_frag *qent, *beg, *end;
1416 struct timeval now, age;
1417 struct mbuf *m;
1418 meta_p meta;
1419 int i, seq;
1420 item_p item;
1421
1422 now.tv_sec = 0; /* uninitialized state */
1423 while (1) {
1424
1425 /* If queue is empty, we're done */
1426 if (TAILQ_EMPTY(&priv->frags))
1427 break;
1428
1429 /* Find the first complete packet in the queue */
1430 beg = end = NULL;
1431 seq = TAILQ_FIRST(&priv->frags)->seq;
1432 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1433 if (qent->first)
1434 beg = qent;
1435 else if (qent->seq != seq)
1436 beg = NULL;
1437 if (beg != NULL && qent->last) {
1438 end = qent;
1439 break;
1440 }
1441 seq = MP_NEXT_RECV_SEQ(priv, seq);
1442 }
1443
1444 /* If none found, exit */
1445 if (end == NULL)
1446 break;
1447
1448 /* Get current time (we assume we've been up for >= 1 second) */
1449 if (now.tv_sec == 0)
1450 getmicrouptime(&now);
1451
1452 /* Check if packet has been queued too long */
1453 age = now;
1454 timevalsub(&age, &beg->timestamp);
1455 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1456 break;
1457
1458 /* Throw away junk fragments in front of the completed packet */
1459 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) {
1460 KASSERT(!TAILQ_EMPTY(&priv->frags),
1461 ("%s: empty q", __func__));
1462 priv->bundleStats.dropFragments++;
1463 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1464 NG_FREE_M(qent->data);
1465 NG_FREE_META(qent->meta);
1466 FREE(qent, M_NETGRAPH_PPP);
1467 priv->qlen--;
1468 }
1469
1470 /* Extract completed packet */
1471 ng_ppp_get_packet(node, &m, &meta);
1472
1473 /* Bump MSEQ if necessary */
1474 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) {
1475 priv->mseq = end->seq;
1476 for (i = 0; i < priv->numActiveLinks; i++) {
1477 struct ng_ppp_link *const alink =
1478 &priv->links[priv->activeLinks[i]];
1479
1480 if (MP_RECV_SEQ_DIFF(priv,
1481 alink->seq, priv->mseq) < 0)
1482 alink->seq = priv->mseq;
1483 }
1484 }
1485
1486 /* Deliver packet */
1487 item = ng_package_data(m, meta);
1488 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item);
1489 }
1490}
1491
1492/*
1493 * Periodically call ng_ppp_frag_checkstale()
1494 */
1495static void
1496ng_ppp_frag_timeout(void *arg)
1497{
1498 const node_p node = arg;
1499 const priv_p priv = NG_NODE_PRIVATE(node);
1500 int s = splnet();
1501
1502 /* Handle the race where shutdown happens just before splnet() above */
1503 if (NG_NODE_NOT_VALID(node)) {
1504 NG_NODE_UNREF(node);
1505 splx(s);
1506 return;
1507 }
1508
1509 /* Reset timer state after timeout */
1510 KASSERT(priv->timerActive, ("%s: !timerActive", __func__));
1511 priv->timerActive = 0;
1512 KASSERT(node->nd_refs > 1, ("%s: nd_refs=%d", __func__, node->nd_refs));
1513 NG_NODE_UNREF(node);
1514
1515 /* Start timer again */
1516 ng_ppp_start_frag_timer(node);
1517
1518 /* Scan the fragment queue */
1519 ng_ppp_frag_checkstale(node);
1520 splx(s);
1521}
1522
1523/*
1524 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1525 * the frame across the individual PPP links and do so.
1526 */
1527static int
1528ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1529{
1530 const priv_p priv = NG_NODE_PRIVATE(node);
1531 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4;
1532 int distrib[NG_PPP_MAX_LINKS];
1533 int firstFragment;
1534 int activeLinkNum;
1535 item_p item;
1536
1537 /* At least one link must be active */
1538 if (priv->numActiveLinks == 0) {
1539 NG_FREE_M(m);
1540 NG_FREE_META(meta);
1541 return (ENETDOWN);
1542 }
1543
1544 /* Round-robin strategy */
1545 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1546 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1547 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1548 distrib[activeLinkNum] = m->m_pkthdr.len;
1549 goto deliver;
1550 }
1551
1552 /* Strategy when all links are equivalent (optimize the common case) */
1553 if (priv->allLinksEqual) {
1554 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1555 int i, remain;
1556
1557 for (i = 0; i < priv->numActiveLinks; i++)
1558 distrib[priv->lastLink++ % priv->numActiveLinks]
1559 = fraction;
1560 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1561 while (remain > 0) {
1562 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1563 remain--;
1564 }
1565 goto deliver;
1566 }
1567
1568 /* Strategy when all links are not equivalent */
1569 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1570
1571deliver:
1572 /* Update stats */
1573 priv->bundleStats.xmitFrames++;
1574 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1575
1576 /* Send alloted portions of frame out on the link(s) */
1577 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1578 activeLinkNum >= 0; activeLinkNum--) {
1579 const int linkNum = priv->activeLinks[activeLinkNum];
1580 struct ng_ppp_link *const link = &priv->links[linkNum];
1581
1582 /* Deliver fragment(s) out the next link */
1583 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1584 int len, lastFragment, error;
1585 struct mbuf *m2;
1586 meta_p meta2;
1587
1588 /* Calculate fragment length; don't exceed link MTU */
1589 len = distrib[activeLinkNum];
1590 if (len > link->conf.mru - hdr_len)
1591 len = link->conf.mru - hdr_len;
1592 distrib[activeLinkNum] -= len;
1593 lastFragment = (len == m->m_pkthdr.len);
1594
1595 /* Split off next fragment as "m2" */
1596 m2 = m;
1597 if (!lastFragment) {
|