ng_ppp.c revision 87599
1275970Scy 2275970Scy/* 3275970Scy * ng_ppp.c 4275970Scy * 5275970Scy * Copyright (c) 1996-2000 Whistle Communications, Inc. 6275970Scy * All rights reserved. 7275970Scy * 8275970Scy * Subject to the following obligations and disclaimer of warranty, use and 9275970Scy * redistribution of this software, in source or object code forms, with or 10275970Scy * without modifications are expressly permitted by Whistle Communications; 11275970Scy * provided, however, that: 12275970Scy * 1. Any and all reproductions of the source or object code must include the 13275970Scy * copyright notice above and the following disclaimer of warranties; and 14275970Scy * 2. No rights are granted, in any manner or form, to use Whistle 15275970Scy * Communications, Inc. trademarks, including the mark "WHISTLE 16275970Scy * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 17275970Scy * such appears in the above copyright notice or in the software. 18275970Scy * 19275970Scy * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 20275970Scy * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 21275970Scy * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 22275970Scy * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 23275970Scy * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 24275970Scy * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 25275970Scy * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 26275970Scy * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 27275970Scy * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 28275970Scy * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 29275970Scy * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 30275970Scy * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 31275970Scy * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 32275970Scy * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33275970Scy * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34275970Scy * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 35 * OF SUCH DAMAGE. 36 * 37 * Author: Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD: head/sys/netgraph/ng_ppp.c 87599 2001-12-10 08:09:49Z obrien $ 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 (((seq) + 1) & ((priv)->conf.recvShortSeq ? \ 123 MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK)) 124 125/* Don't fragment transmitted packets smaller than this */ 126#define MP_MIN_FRAG_LEN 6 127 128/* Maximum fragment reasssembly queue length */ 129#define MP_MAX_QUEUE_LEN 128 130 131/* Fragment queue scanner period */ 132#define MP_FRAGTIMER_INTERVAL (hz/2) 133 134/* We store incoming fragments this way */ 135struct ng_ppp_frag { 136 int seq; /* fragment seq# */ 137 u_char first; /* First in packet? */ 138 u_char last; /* Last in packet? */ 139 struct timeval timestamp; /* time of reception */ 140 struct mbuf *data; /* Fragment data */ 141 meta_p meta; /* Fragment meta */ 142 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */ 143}; 144 145/* We use integer indicies to refer to the non-link hooks */ 146static const char *const ng_ppp_hook_names[] = { 147 NG_PPP_HOOK_ATALK, 148#define HOOK_INDEX_ATALK 0 149 NG_PPP_HOOK_BYPASS, 150#define HOOK_INDEX_BYPASS 1 151 NG_PPP_HOOK_COMPRESS, 152#define HOOK_INDEX_COMPRESS 2 153 NG_PPP_HOOK_ENCRYPT, 154#define HOOK_INDEX_ENCRYPT 3 155 NG_PPP_HOOK_DECOMPRESS, 156#define HOOK_INDEX_DECOMPRESS 4 157 NG_PPP_HOOK_DECRYPT, 158#define HOOK_INDEX_DECRYPT 5 159 NG_PPP_HOOK_INET, 160#define HOOK_INDEX_INET 6 161 NG_PPP_HOOK_IPX, 162#define HOOK_INDEX_IPX 7 163 NG_PPP_HOOK_VJC_COMP, 164#define HOOK_INDEX_VJC_COMP 8 165 NG_PPP_HOOK_VJC_IP, 166#define HOOK_INDEX_VJC_IP 9 167 NG_PPP_HOOK_VJC_UNCOMP, 168#define HOOK_INDEX_VJC_UNCOMP 10 169 NG_PPP_HOOK_VJC_VJIP, 170#define HOOK_INDEX_VJC_VJIP 11 171 NG_PPP_HOOK_IPV6, 172#define HOOK_INDEX_IPV6 12 173 NULL 174#define HOOK_INDEX_MAX 13 175}; 176 177/* We store index numbers in the hook private pointer. The HOOK_INDEX() 178 for a hook is either the index (above) for normal hooks, or the ones 179 complement of the link number for link hooks. 180XXX Not any more.. (what a hack) 181#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private)) 182*/ 183 184/* Per-link private information */ 185struct ng_ppp_link { 186 struct ng_ppp_link_conf conf; /* link configuration */ 187 hook_p hook; /* connection to link data */ 188 int32_t seq; /* highest rec'd seq# - MSEQ */ 189 struct timeval lastWrite; /* time of last write */ 190 int bytesInQueue; /* bytes in the output queue */ 191 struct ng_ppp_link_stat stats; /* Link stats */ 192}; 193 194/* Total per-node private information */ 195struct ng_ppp_private { 196 struct ng_ppp_bund_conf conf; /* bundle config */ 197 struct ng_ppp_link_stat bundleStats; /* bundle stats */ 198 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */ 199 int32_t xseq; /* next out MP seq # */ 200 int32_t mseq; /* min links[i].seq */ 201 u_char vjCompHooked; /* VJ comp hooked up? */ 202 u_char allLinksEqual; /* all xmit the same? */ 203 u_char timerActive; /* frag timer active? */ 204 u_int numActiveLinks; /* how many links up */ 205 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */ 206 u_int lastLink; /* for round robin */ 207 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */ 208 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */ 209 frags; 210 int qlen; /* fraq queue length */ 211 struct callout_handle fragTimer; /* fraq queue check */ 212}; 213typedef struct ng_ppp_private *priv_p; 214 215/* Netgraph node methods */ 216static ng_constructor_t ng_ppp_constructor; 217static ng_rcvmsg_t ng_ppp_rcvmsg; 218static ng_shutdown_t ng_ppp_shutdown; 219static ng_newhook_t ng_ppp_newhook; 220static ng_rcvdata_t ng_ppp_rcvdata; 221static ng_disconnect_t ng_ppp_disconnect; 222 223/* Helper functions */ 224static int ng_ppp_input(node_p node, int bypass, 225 int linkNum, item_p item); 226static int ng_ppp_output(node_p node, int bypass, int proto, 227 int linkNum, item_p item); 228static int ng_ppp_mp_input(node_p node, int linkNum, item_p item); 229static int ng_ppp_check_packet(node_p node); 230static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap); 231static int ng_ppp_frag_process(node_p node); 232static int ng_ppp_frag_trim(node_p node); 233static void ng_ppp_frag_timeout(void *arg); 234static void ng_ppp_frag_checkstale(node_p node); 235static void ng_ppp_frag_reset(node_p node); 236static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta); 237static void ng_ppp_mp_strategy(node_p node, int len, int *distrib); 238static int ng_ppp_intcmp(const void *v1, const void *v2); 239static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK); 240static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len); 241static int ng_ppp_config_valid(node_p node, 242 const struct ng_ppp_node_conf *newConf); 243static void ng_ppp_update(node_p node, int newConf); 244static void ng_ppp_start_frag_timer(node_p node); 245static void ng_ppp_stop_frag_timer(node_p node); 246 247/* Parse type for struct ng_ppp_mp_state_type */ 248static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = { 249 &ng_parse_hint32_type, 250 NG_PPP_MAX_LINKS 251}; 252static const struct ng_parse_type ng_ppp_rseq_array_type = { 253 &ng_parse_fixedarray_type, 254 &ng_ppp_rseq_array_info, 255}; 256static const struct ng_parse_struct_info ng_ppp_mp_state_type_info 257 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type); 258static const struct ng_parse_type ng_ppp_mp_state_type = { 259 &ng_parse_struct_type, 260 &ng_ppp_mp_state_type_info, 261}; 262 263/* Parse type for struct ng_ppp_link_conf */ 264static const struct ng_parse_struct_info 265 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO; 266static const struct ng_parse_type ng_ppp_link_type = { 267 &ng_parse_struct_type, 268 &ng_ppp_link_type_info, 269}; 270 271/* Parse type for struct ng_ppp_bund_conf */ 272static const struct ng_parse_struct_info 273 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO; 274static const struct ng_parse_type ng_ppp_bund_type = { 275 &ng_parse_struct_type, 276 &ng_ppp_bund_type_info, 277}; 278 279/* Parse type for struct ng_ppp_node_conf */ 280static const struct ng_parse_fixedarray_info ng_ppp_array_info = { 281 &ng_ppp_link_type, 282 NG_PPP_MAX_LINKS 283}; 284static const struct ng_parse_type ng_ppp_link_array_type = { 285 &ng_parse_fixedarray_type, 286 &ng_ppp_array_info, 287}; 288static const struct ng_parse_struct_info ng_ppp_conf_type_info 289 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type); 290static const struct ng_parse_type ng_ppp_conf_type = { 291 &ng_parse_struct_type, 292 &ng_ppp_conf_type_info 293}; 294 295/* Parse type for struct ng_ppp_link_stat */ 296static const struct ng_parse_struct_info 297 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO; 298static const struct ng_parse_type ng_ppp_stats_type = { 299 &ng_parse_struct_type, 300 &ng_ppp_stats_type_info 301}; 302 303/* List of commands and how to convert arguments to/from ASCII */ 304static const struct ng_cmdlist ng_ppp_cmds[] = { 305 { 306 NGM_PPP_COOKIE, 307 NGM_PPP_SET_CONFIG, 308 "setconfig", 309 &ng_ppp_conf_type, 310 NULL 311 }, 312 { 313 NGM_PPP_COOKIE, 314 NGM_PPP_GET_CONFIG, 315 "getconfig", 316 NULL, 317 &ng_ppp_conf_type 318 }, 319 { 320 NGM_PPP_COOKIE, 321 NGM_PPP_GET_MP_STATE, 322 "getmpstate", 323 NULL, 324 &ng_ppp_mp_state_type 325 }, 326 { 327 NGM_PPP_COOKIE, 328 NGM_PPP_GET_LINK_STATS, 329 "getstats", 330 &ng_parse_int16_type, 331 &ng_ppp_stats_type 332 }, 333 { 334 NGM_PPP_COOKIE, 335 NGM_PPP_CLR_LINK_STATS, 336 "clrstats", 337 &ng_parse_int16_type, 338 NULL 339 }, 340 { 341 NGM_PPP_COOKIE, 342 NGM_PPP_GETCLR_LINK_STATS, 343 "getclrstats", 344 &ng_parse_int16_type, 345 &ng_ppp_stats_type 346 }, 347 { 0 } 348}; 349 350/* Node type descriptor */ 351static struct ng_type ng_ppp_typestruct = { 352 NG_ABI_VERSION, 353 NG_PPP_NODE_TYPE, 354 NULL, 355 ng_ppp_constructor, 356 ng_ppp_rcvmsg, 357 ng_ppp_shutdown, 358 ng_ppp_newhook, 359 NULL, 360 NULL, 361 ng_ppp_rcvdata, 362 ng_ppp_disconnect, 363 ng_ppp_cmds 364}; 365NETGRAPH_INIT(ppp, &ng_ppp_typestruct); 366 367static int *compareLatencies; /* hack for ng_ppp_intcmp() */ 368 369/* Address and control field header */ 370static const u_char ng_ppp_acf[2] = { 0xff, 0x03 }; 371 372/* Maximum time we'll let a complete incoming packet sit in the queue */ 373static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */ 374 375#define ERROUT(x) do { error = (x); goto done; } while (0) 376 377/************************************************************************ 378 NETGRAPH NODE STUFF 379 ************************************************************************/ 380 381/* 382 * Node type constructor 383 */ 384static int 385ng_ppp_constructor(node_p node) 386{ 387 priv_p priv; 388 int i; 389 390 /* Allocate private structure */ 391 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_PPP, M_NOWAIT | M_ZERO); 392 if (priv == NULL) 393 return (ENOMEM); 394 395 NG_NODE_SET_PRIVATE(node, priv); 396 397 /* Initialize state */ 398 TAILQ_INIT(&priv->frags); 399 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 400 priv->links[i].seq = MP_NOSEQ; 401 callout_handle_init(&priv->fragTimer); 402 403 /* Done */ 404 return (0); 405} 406 407/* 408 * Give our OK for a hook to be added 409 */ 410static int 411ng_ppp_newhook(node_p node, hook_p hook, const char *name) 412{ 413 const priv_p priv = NG_NODE_PRIVATE(node); 414 int linkNum = -1; 415 hook_p *hookPtr = NULL; 416 int hookIndex = -1; 417 418 /* Figure out which hook it is */ 419 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */ 420 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) { 421 const char *cp; 422 char *eptr; 423 424 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX); 425 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 426 return (EINVAL); 427 linkNum = (int)strtoul(cp, &eptr, 10); 428 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS) 429 return (EINVAL); 430 hookPtr = &priv->links[linkNum].hook; 431 hookIndex = ~linkNum; 432 } else { /* must be a non-link hook */ 433 int i; 434 435 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) { 436 if (strcmp(name, ng_ppp_hook_names[i]) == 0) { 437 hookPtr = &priv->hooks[i]; 438 hookIndex = i; 439 break; 440 } 441 } 442 if (ng_ppp_hook_names[i] == NULL) 443 return (EINVAL); /* no such hook */ 444 } 445 446 /* See if hook is already connected */ 447 if (*hookPtr != NULL) 448 return (EISCONN); 449 450 /* Disallow more than one link unless multilink is enabled */ 451 if (linkNum != -1 && priv->links[linkNum].conf.enableLink 452 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1) 453 return (ENODEV); 454 455 /* OK */ 456 *hookPtr = hook; 457 NG_HOOK_SET_PRIVATE(hook, (void *)hookIndex); 458 ng_ppp_update(node, 0); 459 return (0); 460} 461 462/* 463 * Receive a control message 464 */ 465static int 466ng_ppp_rcvmsg(node_p node, item_p item, hook_p lasthook) 467{ 468 const priv_p priv = NG_NODE_PRIVATE(node); 469 struct ng_mesg *resp = NULL; 470 int error = 0; 471 struct ng_mesg *msg; 472 473 NGI_GET_MSG(item, msg); 474 switch (msg->header.typecookie) { 475 case NGM_PPP_COOKIE: 476 switch (msg->header.cmd) { 477 case NGM_PPP_SET_CONFIG: 478 { 479 struct ng_ppp_node_conf *const conf = 480 (struct ng_ppp_node_conf *)msg->data; 481 int i; 482 483 /* Check for invalid or illegal config */ 484 if (msg->header.arglen != sizeof(*conf)) 485 ERROUT(EINVAL); 486 if (!ng_ppp_config_valid(node, conf)) 487 ERROUT(EINVAL); 488 489 /* Copy config */ 490 priv->conf = conf->bund; 491 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 492 priv->links[i].conf = conf->links[i]; 493 ng_ppp_update(node, 1); 494 break; 495 } 496 case NGM_PPP_GET_CONFIG: 497 { 498 struct ng_ppp_node_conf *conf; 499 int i; 500 501 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT); 502 if (resp == NULL) 503 ERROUT(ENOMEM); 504 conf = (struct ng_ppp_node_conf *)resp->data; 505 conf->bund = priv->conf; 506 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 507 conf->links[i] = priv->links[i].conf; 508 break; 509 } 510 case NGM_PPP_GET_MP_STATE: 511 { 512 struct ng_ppp_mp_state *info; 513 int i; 514 515 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT); 516 if (resp == NULL) 517 ERROUT(ENOMEM); 518 info = (struct ng_ppp_mp_state *)resp->data; 519 bzero(info, sizeof(*info)); 520 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 521 if (priv->links[i].seq != MP_NOSEQ) 522 info->rseq[i] = priv->links[i].seq; 523 } 524 info->mseq = priv->mseq; 525 info->xseq = priv->xseq; 526 break; 527 } 528 case NGM_PPP_GET_LINK_STATS: 529 case NGM_PPP_CLR_LINK_STATS: 530 case NGM_PPP_GETCLR_LINK_STATS: 531 { 532 struct ng_ppp_link_stat *stats; 533 u_int16_t linkNum; 534 535 if (msg->header.arglen != sizeof(u_int16_t)) 536 ERROUT(EINVAL); 537 linkNum = *((u_int16_t *) msg->data); 538 if (linkNum >= NG_PPP_MAX_LINKS 539 && linkNum != NG_PPP_BUNDLE_LINKNUM) 540 ERROUT(EINVAL); 541 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ? 542 &priv->bundleStats : &priv->links[linkNum].stats; 543 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) { 544 NG_MKRESPONSE(resp, msg, 545 sizeof(struct ng_ppp_link_stat), M_NOWAIT); 546 if (resp == NULL) 547 ERROUT(ENOMEM); 548 bcopy(stats, resp->data, sizeof(*stats)); 549 } 550 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS) 551 bzero(stats, sizeof(*stats)); 552 break; 553 } 554 default: 555 error = EINVAL; 556 break; 557 } 558 break; 559 case NGM_VJC_COOKIE: 560 { 561 /* 562 * Forward it to the vjc node. leave the 563 * old return address alone. 564 * If we have no hook, let NG_RESPOND_MSG 565 * clean up any remaining resources. 566 * Because we have no resp, the item will be freed 567 * along with anything it references. Don't 568 * let msg be freed twice. 569 */ 570 NGI_MSG(item) = msg; /* put it back in the item */ 571 msg = NULL; 572 if ((lasthook = priv->links[HOOK_INDEX_VJC_IP].hook)) { 573 NG_FWD_ITEM_HOOK(error, item, lasthook); 574 } 575 return (error); 576 } 577 default: 578 error = EINVAL; 579 break; 580 } 581done: 582 NG_RESPOND_MSG(error, node, item, resp); 583 NG_FREE_MSG(msg); 584 return (error); 585} 586 587/* 588 * Receive data on a hook 589 */ 590static int 591ng_ppp_rcvdata(hook_p hook, item_p item) 592{ 593 const node_p node = NG_HOOK_NODE(hook); 594 const priv_p priv = NG_NODE_PRIVATE(node); 595 const int index = (int)NG_HOOK_PRIVATE(hook); 596 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM; 597 hook_p outHook = NULL; 598 int proto = 0, error; 599 struct mbuf *m; 600 601 NGI_GET_M(item, m); 602 /* Did it come from a link hook? */ 603 if (index < 0) { 604 struct ng_ppp_link *link; 605 606 /* Convert index into a link number */ 607 linkNum = (u_int16_t)~index; 608 KASSERT(linkNum < NG_PPP_MAX_LINKS, 609 ("%s: bogus index 0x%x", __func__, index)); 610 link = &priv->links[linkNum]; 611 612 /* Stats */ 613 link->stats.recvFrames++; 614 link->stats.recvOctets += m->m_pkthdr.len; 615 616 /* Strip address and control fields, if present */ 617 if (m->m_pkthdr.len >= 2) { 618 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 619 NG_FREE_ITEM(item); 620 return (ENOBUFS); 621 } 622 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0) 623 m_adj(m, 2); 624 } 625 626 /* Dispatch incoming frame (if not enabled, to bypass) */ 627 NGI_M(item) = m; /* put changed m back in item */ 628 return ng_ppp_input(node, 629 !link->conf.enableLink, linkNum, item); 630 } 631 632 /* Get protocol & check if data allowed from this hook */ 633 NGI_M(item) = m; /* put possibly changed m back in item */ 634 switch (index) { 635 636 /* Outgoing data */ 637 case HOOK_INDEX_ATALK: 638 if (!priv->conf.enableAtalk) { 639 NG_FREE_ITEM(item); 640 return (ENXIO); 641 } 642 proto = PROT_APPLETALK; 643 break; 644 case HOOK_INDEX_IPX: 645 if (!priv->conf.enableIPX) { 646 NG_FREE_ITEM(item); 647 return (ENXIO); 648 } 649 proto = PROT_IPX; 650 break; 651 case HOOK_INDEX_IPV6: 652 if (!priv->conf.enableIPv6) { 653 NG_FREE_ITEM(item); 654 return (ENXIO); 655 } 656 proto = PROT_IPV6; 657 break; 658 case HOOK_INDEX_INET: 659 case HOOK_INDEX_VJC_VJIP: 660 if (!priv->conf.enableIP) { 661 NG_FREE_ITEM(item); 662 return (ENXIO); 663 } 664 proto = PROT_IP; 665 break; 666 case HOOK_INDEX_VJC_COMP: 667 if (!priv->conf.enableVJCompression) { 668 NG_FREE_ITEM(item); 669 return (ENXIO); 670 } 671 proto = PROT_VJCOMP; 672 break; 673 case HOOK_INDEX_VJC_UNCOMP: 674 if (!priv->conf.enableVJCompression) { 675 NG_FREE_ITEM(item); 676 return (ENXIO); 677 } 678 proto = PROT_VJUNCOMP; 679 break; 680 case HOOK_INDEX_COMPRESS: 681 if (!priv->conf.enableCompression) { 682 NG_FREE_ITEM(item); 683 return (ENXIO); 684 } 685 proto = PROT_COMPD; 686 break; 687 case HOOK_INDEX_ENCRYPT: 688 if (!priv->conf.enableEncryption) { 689 NG_FREE_ITEM(item); 690 return (ENXIO); 691 } 692 proto = PROT_CRYPTD; 693 break; 694 case HOOK_INDEX_BYPASS: 695 if (m->m_pkthdr.len < 4) { 696 NG_FREE_ITEM(item); 697 return (EINVAL); 698 } 699 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 700 NGI_M(item) = NULL; /* don't free twice */ 701 NG_FREE_ITEM(item); 702 return (ENOBUFS); 703 } 704 NGI_M(item) = m; /* m may have changed */ 705 linkNum = ntohs(mtod(m, u_int16_t *)[0]); 706 proto = ntohs(mtod(m, u_int16_t *)[1]); 707 m_adj(m, 4); 708 if (linkNum >= NG_PPP_MAX_LINKS 709 && linkNum != NG_PPP_BUNDLE_LINKNUM) { 710 NG_FREE_ITEM(item); 711 return (EINVAL); 712 } 713 break; 714 715 /* Incoming data */ 716 case HOOK_INDEX_VJC_IP: 717 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) { 718 NG_FREE_ITEM(item); 719 return (ENXIO); 720 } 721 break; 722 case HOOK_INDEX_DECOMPRESS: 723 if (!priv->conf.enableDecompression) { 724 NG_FREE_ITEM(item); 725 return (ENXIO); 726 } 727 break; 728 case HOOK_INDEX_DECRYPT: 729 if (!priv->conf.enableDecryption) { 730 NG_FREE_ITEM(item); 731 return (ENXIO); 732 } 733 break; 734 default: 735 panic("%s: bogus index 0x%x", __func__, index); 736 } 737 738 /* Now figure out what to do with the frame */ 739 switch (index) { 740 741 /* Outgoing data */ 742 case HOOK_INDEX_INET: 743 if (priv->conf.enableVJCompression && priv->vjCompHooked) { 744 outHook = priv->hooks[HOOK_INDEX_VJC_IP]; 745 break; 746 } 747 /* FALLTHROUGH */ 748 case HOOK_INDEX_ATALK: 749 case HOOK_INDEX_IPV6: 750 case HOOK_INDEX_IPX: 751 case HOOK_INDEX_VJC_COMP: 752 case HOOK_INDEX_VJC_UNCOMP: 753 case HOOK_INDEX_VJC_VJIP: 754 if (priv->conf.enableCompression 755 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) { 756 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 757 NGI_M(item) = NULL; 758 NG_FREE_ITEM(item); 759 return (ENOBUFS); 760 } 761 NGI_M(item) = m; /* m may have changed */ 762 outHook = priv->hooks[HOOK_INDEX_COMPRESS]; 763 break; 764 } 765 /* FALLTHROUGH */ 766 case HOOK_INDEX_COMPRESS: 767 if (priv->conf.enableEncryption 768 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) { 769 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 770 NGI_M(item) = NULL; 771 NG_FREE_ITEM(item); 772 return (ENOBUFS); 773 } 774 NGI_M(item) = m; /* m may have changed */ 775 outHook = priv->hooks[HOOK_INDEX_ENCRYPT]; 776 break; 777 } 778 /* FALLTHROUGH */ 779 case HOOK_INDEX_ENCRYPT: 780 return ng_ppp_output(node, 0, proto, NG_PPP_BUNDLE_LINKNUM, item); 781 782 case HOOK_INDEX_BYPASS: 783 return ng_ppp_output(node, 1, proto, linkNum, item); 784 785 /* Incoming data */ 786 case HOOK_INDEX_DECRYPT: 787 case HOOK_INDEX_DECOMPRESS: 788 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 789 790 case HOOK_INDEX_VJC_IP: 791 outHook = priv->hooks[HOOK_INDEX_INET]; 792 break; 793 } 794 795 /* Send packet out hook */ 796 NG_FWD_ITEM_HOOK(error, item, outHook); 797 return (error); 798} 799 800/* 801 * Destroy node 802 */ 803static int 804ng_ppp_shutdown(node_p node) 805{ 806 const priv_p priv = NG_NODE_PRIVATE(node); 807 808 /* Stop fragment queue timer */ 809 ng_ppp_stop_frag_timer(node); 810 811 /* Take down netgraph node */ 812 ng_ppp_frag_reset(node); 813 bzero(priv, sizeof(*priv)); 814 FREE(priv, M_NETGRAPH_PPP); 815 NG_NODE_SET_PRIVATE(node, NULL); 816 NG_NODE_UNREF(node); /* let the node escape */ 817 return (0); 818} 819 820/* 821 * Hook disconnection 822 */ 823static int 824ng_ppp_disconnect(hook_p hook) 825{ 826 const node_p node = NG_HOOK_NODE(hook); 827 const priv_p priv = NG_NODE_PRIVATE(node); 828 const int index = (int)NG_HOOK_PRIVATE(hook); 829 830 /* Zero out hook pointer */ 831 if (index < 0) 832 priv->links[~index].hook = NULL; 833 else 834 priv->hooks[index] = NULL; 835 836 /* Update derived info (or go away if no hooks left) */ 837 if (NG_NODE_NUMHOOKS(node) > 0) { 838 ng_ppp_update(node, 0); 839 } else { 840 if (NG_NODE_IS_VALID(node)) { 841 ng_rmnode_self(node); 842 } 843 } 844 return (0); 845} 846 847/************************************************************************ 848 HELPER STUFF 849 ************************************************************************/ 850 851/* 852 * Handle an incoming frame. Extract the PPP protocol number 853 * and dispatch accordingly. 854 */ 855static int 856ng_ppp_input(node_p node, int bypass, int linkNum, item_p item) 857{ 858 const priv_p priv = NG_NODE_PRIVATE(node); 859 hook_p outHook = NULL; 860 int proto, error; 861 struct mbuf *m; 862 863 864 NGI_GET_M(item, m); 865 /* Extract protocol number */ 866 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) { 867 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) { 868 NG_FREE_ITEM(item); 869 return (ENOBUFS); 870 } 871 proto = (proto << 8) + *mtod(m, u_char *); 872 m_adj(m, 1); 873 } 874 if (!PROT_VALID(proto)) { 875 if (linkNum == NG_PPP_BUNDLE_LINKNUM) 876 priv->bundleStats.badProtos++; 877 else 878 priv->links[linkNum].stats.badProtos++; 879 NG_FREE_ITEM(item); 880 NG_FREE_M(m); 881 return (EINVAL); 882 } 883 884 /* Bypass frame? */ 885 if (bypass) 886 goto bypass; 887 888 /* Check protocol */ 889 switch (proto) { 890 case PROT_COMPD: 891 if (priv->conf.enableDecompression) 892 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS]; 893 break; 894 case PROT_CRYPTD: 895 if (priv->conf.enableDecryption) 896 outHook = priv->hooks[HOOK_INDEX_DECRYPT]; 897 break; 898 case PROT_VJCOMP: 899 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 900 outHook = priv->hooks[HOOK_INDEX_VJC_COMP]; 901 break; 902 case PROT_VJUNCOMP: 903 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 904 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP]; 905 break; 906 case PROT_MP: 907 if (priv->conf.enableMultilink 908 && linkNum != NG_PPP_BUNDLE_LINKNUM) 909 return ng_ppp_mp_input(node, linkNum, item); 910 break; 911 case PROT_APPLETALK: 912 if (priv->conf.enableAtalk) 913 outHook = priv->hooks[HOOK_INDEX_ATALK]; 914 break; 915 case PROT_IPX: 916 if (priv->conf.enableIPX) 917 outHook = priv->hooks[HOOK_INDEX_IPX]; 918 break; 919 case PROT_IP: 920 if (priv->conf.enableIP) 921 outHook = priv->hooks[HOOK_INDEX_INET]; 922 break; 923 case PROT_IPV6: 924 if (priv->conf.enableIPv6) 925 outHook = priv->hooks[HOOK_INDEX_IPV6]; 926 break; 927 } 928 929bypass: 930 /* For unknown/inactive protocols, forward out the bypass hook */ 931 if (outHook == NULL) { 932 u_int16_t hdr[2]; 933 934 hdr[0] = htons(linkNum); 935 hdr[1] = htons((u_int16_t)proto); 936 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) { 937 NG_FREE_ITEM(item); 938 return (ENOBUFS); 939 } 940 outHook = priv->hooks[HOOK_INDEX_BYPASS]; 941 } 942 943 /* Forward frame */ 944 NG_FWD_NEW_DATA(error, item, outHook, m); 945 return (error); 946} 947 948/* 949 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM 950 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0. 951 */ 952static int 953ng_ppp_output(node_p node, int bypass, 954 int proto, int linkNum, item_p item) 955{ 956 const priv_p priv = NG_NODE_PRIVATE(node); 957 struct ng_ppp_link *link; 958 int len, error; 959 struct mbuf *m; 960 961 NGI_GET_M(item, m); /* separate them for a while */ 962 /* If not doing MP, map bundle virtual link to (the only) link */ 963 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink) 964 linkNum = priv->activeLinks[0]; 965 966 /* Get link pointer (optimization) */ 967 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ? 968 &priv->links[linkNum] : NULL; 969 970 /* Check link status (if real) */ 971 if (linkNum != NG_PPP_BUNDLE_LINKNUM) { 972 if (!bypass && !link->conf.enableLink) { 973 NG_FREE_M(m); 974 NG_FREE_ITEM(item); 975 return (ENXIO); 976 } 977 if (link->hook == NULL) { 978 NG_FREE_M(m); 979 NG_FREE_ITEM(item); 980 return (ENETDOWN); 981 } 982 } 983 984 /* Prepend protocol number, possibly compressed */ 985 if ((m = ng_ppp_addproto(m, proto, 986 linkNum == NG_PPP_BUNDLE_LINKNUM 987 || link->conf.enableProtoComp)) == NULL) { 988 NG_FREE_ITEM(item); 989 return (ENOBUFS); 990 } 991 992 /* Special handling for the MP virtual link */ 993 if (linkNum == NG_PPP_BUNDLE_LINKNUM) { 994 meta_p meta; 995 996 /* strip off and discard the queue item */ 997 NGI_GET_META(item, meta); 998 NG_FREE_ITEM(item); 999 return ng_ppp_mp_output(node, m, meta); 1000 } 1001 1002 /* Prepend address and control field (unless compressed) */ 1003 if (proto == PROT_LCP || !link->conf.enableACFComp) { 1004 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) { 1005 NG_FREE_ITEM(item); 1006 return (ENOBUFS); 1007 } 1008 } 1009 1010 /* Deliver frame */ 1011 len = m->m_pkthdr.len; 1012 NG_FWD_NEW_DATA(error, item, link->hook, m); 1013 1014 /* Update stats and 'bytes in queue' counter */ 1015 if (error == 0) { 1016 link->stats.xmitFrames++; 1017 link->stats.xmitOctets += len; 1018 link->bytesInQueue += len; 1019 getmicrouptime(&link->lastWrite); 1020 } 1021 return error; 1022} 1023 1024/* 1025 * Handle an incoming multi-link fragment 1026 * 1027 * The fragment reassembly algorithm is somewhat complex. This is mainly 1028 * because we are required not to reorder the reconstructed packets, yet 1029 * fragments are only guaranteed to arrive in order on a per-link basis. 1030 * In other words, when we have a complete packet ready, but the previous 1031 * packet is still incomplete, we have to decide between delivering the 1032 * complete packet and throwing away the incomplete one, or waiting to 1033 * see if the remainder of the incomplete one arrives, at which time we 1034 * can deliver both packets, in order. 1035 * 1036 * This problem is exacerbated by "sequence number slew", which is when 1037 * the sequence numbers coming in from different links are far apart from 1038 * each other. In particular, certain unnamed equipment (*cough* Ascend) 1039 * has been seen to generate sequence number slew of up to 10 on an ISDN 1040 * 2B-channel MP link. There is nothing invalid about sequence number slew 1041 * but it makes the reasssembly process have to work harder. 1042 * 1043 * However, the peer is required to transmit fragments in order on each 1044 * link. That means if we define MSEQ as the minimum over all links of 1045 * the highest sequence number received on that link, then we can always 1046 * give up any hope of receiving a fragment with sequence number < MSEQ in 1047 * the future (all of this using 'wraparound' sequence number space). 1048 * Therefore we can always immediately throw away incomplete packets 1049 * missing fragments with sequence numbers < MSEQ. 1050 * 1051 * Here is an overview of our algorithm: 1052 * 1053 * o Received fragments are inserted into a queue, for which we 1054 * maintain these invariants between calls to this function: 1055 * 1056 * - Fragments are ordered in the queue by sequence number 1057 * - If a complete packet is at the head of the queue, then 1058 * the first fragment in the packet has seq# > MSEQ + 1 1059 * (otherwise, we could deliver it immediately) 1060 * - If any fragments have seq# < MSEQ, then they are necessarily 1061 * part of a packet whose missing seq#'s are all > MSEQ (otherwise, 1062 * we can throw them away because they'll never be completed) 1063 * - The queue contains at most MP_MAX_QUEUE_LEN fragments 1064 * 1065 * o We have a periodic timer that checks the queue for the first 1066 * complete packet that has been sitting in the queue "too long". 1067 * When one is detected, all previous (incomplete) fragments are 1068 * discarded, their missing fragments are declared lost and MSEQ 1069 * is increased. 1070 * 1071 * o If we recieve a fragment with seq# < MSEQ, we throw it away 1072 * because we've already delcared it lost. 1073 * 1074 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM. 1075 */ 1076static int 1077ng_ppp_mp_input(node_p node, int linkNum, item_p item) 1078{ 1079 const priv_p priv = NG_NODE_PRIVATE(node); 1080 struct ng_ppp_link *const link = &priv->links[linkNum]; 1081 struct ng_ppp_frag frag0, *frag = &frag0; 1082 struct ng_ppp_frag *qent; 1083 int i, diff, inserted; 1084 struct mbuf *m; 1085 meta_p meta; 1086 1087 NGI_GET_M(item, m); 1088 NGI_GET_META(item, meta); 1089 NG_FREE_ITEM(item); 1090 /* Stats */ 1091 priv->bundleStats.recvFrames++; 1092 priv->bundleStats.recvOctets += m->m_pkthdr.len; 1093 1094 /* Extract fragment information from MP header */ 1095 if (priv->conf.recvShortSeq) { 1096 u_int16_t shdr; 1097 1098 if (m->m_pkthdr.len < 2) { 1099 link->stats.runts++; 1100 NG_FREE_M(m); 1101 NG_FREE_META(meta); 1102 return (EINVAL); 1103 } 1104 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 1105 NG_FREE_META(meta); 1106 return (ENOBUFS); 1107 } 1108 shdr = ntohs(*mtod(m, u_int16_t *)); 1109 frag->seq = MP_SHORT_EXTEND(shdr); 1110 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0; 1111 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0; 1112 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq); 1113 m_adj(m, 2); 1114 } else { 1115 u_int32_t lhdr; 1116 1117 if (m->m_pkthdr.len < 4) { 1118 link->stats.runts++; 1119 NG_FREE_M(m); 1120 NG_FREE_META(meta); 1121 return (EINVAL); 1122 } 1123 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 1124 NG_FREE_META(meta); 1125 return (ENOBUFS); 1126 } 1127 lhdr = ntohl(*mtod(m, u_int32_t *)); 1128 frag->seq = MP_LONG_EXTEND(lhdr); 1129 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0; 1130 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0; 1131 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq); 1132 m_adj(m, 4); 1133 } 1134 frag->data = m; 1135 frag->meta = meta; 1136 getmicrouptime(&frag->timestamp); 1137 1138 /* If sequence number is < MSEQ, we've already declared this 1139 fragment as lost, so we have no choice now but to drop it */ 1140 if (diff < 0) { 1141 link->stats.dropFragments++; 1142 NG_FREE_M(m); 1143 NG_FREE_META(meta); 1144 return (0); 1145 } 1146 1147 /* Update highest received sequence number on this link and MSEQ */ 1148 priv->mseq = link->seq = frag->seq; 1149 for (i = 0; i < priv->numActiveLinks; i++) { 1150 struct ng_ppp_link *const alink = 1151 &priv->links[priv->activeLinks[i]]; 1152 1153 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0) 1154 priv->mseq = alink->seq; 1155 } 1156 1157 /* Allocate a new frag struct for the queue */ 1158 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH_PPP, M_NOWAIT); 1159 if (frag == NULL) { 1160 NG_FREE_M(m); 1161 NG_FREE_META(meta); 1162 ng_ppp_frag_process(node); 1163 return (ENOMEM); 1164 } 1165 *frag = frag0; 1166 1167 /* Add fragment to queue, which is sorted by sequence number */ 1168 inserted = 0; 1169 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) { 1170 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq); 1171 if (diff > 0) { 1172 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent); 1173 inserted = 1; 1174 break; 1175 } else if (diff == 0) { /* should never happen! */ 1176 link->stats.dupFragments++; 1177 NG_FREE_M(frag->data); 1178 NG_FREE_META(frag->meta); 1179 FREE(frag, M_NETGRAPH_PPP); 1180 return (EINVAL); 1181 } 1182 } 1183 if (!inserted) 1184 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent); 1185 priv->qlen++; 1186 1187 /* Process the queue */ 1188 return ng_ppp_frag_process(node); 1189} 1190 1191/* 1192 * Examine our list of fragments, and determine if there is a 1193 * complete and deliverable packet at the head of the list. 1194 * Return 1 if so, zero otherwise. 1195 */ 1196static int 1197ng_ppp_check_packet(node_p node) 1198{ 1199 const priv_p priv = NG_NODE_PRIVATE(node); 1200 struct ng_ppp_frag *qent, *qnext; 1201 1202 /* Check for empty queue */ 1203 if (TAILQ_EMPTY(&priv->frags)) 1204 return (0); 1205 1206 /* Check first fragment is the start of a deliverable packet */ 1207 qent = TAILQ_FIRST(&priv->frags); 1208 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1) 1209 return (0); 1210 1211 /* Check that all the fragments are there */ 1212 while (!qent->last) { 1213 qnext = TAILQ_NEXT(qent, f_qent); 1214 if (qnext == NULL) /* end of queue */ 1215 return (0); 1216 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)) 1217 return (0); 1218 qent = qnext; 1219 } 1220 1221 /* Got one */ 1222 return (1); 1223} 1224 1225/* 1226 * Pull a completed packet off the head of the incoming fragment queue. 1227 * This assumes there is a completed packet there to pull off. 1228 */ 1229static void 1230ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap) 1231{ 1232 const priv_p priv = NG_NODE_PRIVATE(node); 1233 struct ng_ppp_frag *qent, *qnext; 1234 struct mbuf *m = NULL, *tail; 1235 1236 qent = TAILQ_FIRST(&priv->frags); 1237 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first, 1238 ("%s: no packet", __func__)); 1239 for (tail = NULL; qent != NULL; qent = qnext) { 1240 qnext = TAILQ_NEXT(qent, f_qent); 1241 KASSERT(!TAILQ_EMPTY(&priv->frags), 1242 ("%s: empty q", __func__)); 1243 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1244 if (tail == NULL) { 1245 tail = m = qent->data; 1246 *metap = qent->meta; /* inherit first frag's meta */ 1247 } else { 1248 m->m_pkthdr.len += qent->data->m_pkthdr.len; 1249 tail->m_next = qent->data; 1250 NG_FREE_META(qent->meta); /* drop other frags' metas */ 1251 } 1252 while (tail->m_next != NULL) 1253 tail = tail->m_next; 1254 if (qent->last) 1255 qnext = NULL; 1256 FREE(qent, M_NETGRAPH_PPP); 1257 priv->qlen--; 1258 } 1259 *mp = m; 1260} 1261 1262/* 1263 * Trim fragments from the queue whose packets can never be completed. 1264 * This assumes a complete packet is NOT at the beginning of the queue. 1265 * Returns 1 if fragments were removed, zero otherwise. 1266 */ 1267static int 1268ng_ppp_frag_trim(node_p node) 1269{ 1270 const priv_p priv = NG_NODE_PRIVATE(node); 1271 struct ng_ppp_frag *qent, *qnext = NULL; 1272 int removed = 0; 1273 1274 /* Scan for "dead" fragments and remove them */ 1275 while (1) { 1276 int dead = 0; 1277 1278 /* If queue is empty, we're done */ 1279 if (TAILQ_EMPTY(&priv->frags)) 1280 break; 1281 1282 /* Determine whether first fragment can ever be completed */ 1283 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1284 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0) 1285 break; 1286 qnext = TAILQ_NEXT(qent, f_qent); 1287 KASSERT(qnext != NULL, 1288 ("%s: last frag < MSEQ?", __func__)); 1289 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq) 1290 || qent->last || qnext->first) { 1291 dead = 1; 1292 break; 1293 } 1294 } 1295 if (!dead) 1296 break; 1297 1298 /* Remove fragment and all others in the same packet */ 1299 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) { 1300 KASSERT(!TAILQ_EMPTY(&priv->frags), 1301 ("%s: empty q", __func__)); 1302 priv->bundleStats.dropFragments++; 1303 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1304 NG_FREE_M(qent->data); 1305 NG_FREE_META(qent->meta); 1306 FREE(qent, M_NETGRAPH_PPP); 1307 priv->qlen--; 1308 removed = 1; 1309 } 1310 } 1311 return (removed); 1312} 1313 1314/* 1315 * Run the queue, restoring the queue invariants 1316 */ 1317static int 1318ng_ppp_frag_process(node_p node) 1319{ 1320 const priv_p priv = NG_NODE_PRIVATE(node); 1321 struct mbuf *m; 1322 meta_p meta; 1323 item_p item; 1324 1325 /* Deliver any deliverable packets */ 1326 while (ng_ppp_check_packet(node)) { 1327 ng_ppp_get_packet(node, &m, &meta); 1328 item = ng_package_data(m, meta); 1329 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1330 } 1331 1332 /* Delete dead fragments and try again */ 1333 if (ng_ppp_frag_trim(node)) { 1334 while (ng_ppp_check_packet(node)) { 1335 ng_ppp_get_packet(node, &m, &meta); 1336 item = ng_package_data(m, meta); 1337 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1338 } 1339 } 1340 1341 /* Check for stale fragments while we're here */ 1342 ng_ppp_frag_checkstale(node); 1343 1344 /* Check queue length */ 1345 if (priv->qlen > MP_MAX_QUEUE_LEN) { 1346 struct ng_ppp_frag *qent; 1347 int i; 1348 1349 /* Get oldest fragment */ 1350 KASSERT(!TAILQ_EMPTY(&priv->frags), 1351 ("%s: empty q", __func__)); 1352 qent = TAILQ_FIRST(&priv->frags); 1353 1354 /* Bump MSEQ if necessary */ 1355 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) { 1356 priv->mseq = qent->seq; 1357 for (i = 0; i < priv->numActiveLinks; i++) { 1358 struct ng_ppp_link *const alink = 1359 &priv->links[priv->activeLinks[i]]; 1360 1361 if (MP_RECV_SEQ_DIFF(priv, 1362 alink->seq, priv->mseq) < 0) 1363 alink->seq = priv->mseq; 1364 } 1365 } 1366 1367 /* Drop it */ 1368 priv->bundleStats.dropFragments++; 1369 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1370 NG_FREE_M(qent->data); 1371 NG_FREE_META(qent->meta); 1372 FREE(qent, M_NETGRAPH_PPP); 1373 priv->qlen--; 1374 1375 /* Process queue again */ 1376 return ng_ppp_frag_process(node); 1377 } 1378 1379 /* Done */ 1380 return (0); 1381} 1382 1383/* 1384 * Check for 'stale' completed packets that need to be delivered 1385 * 1386 * If a link goes down or has a temporary failure, MSEQ can get 1387 * "stuck", because no new incoming fragments appear on that link. 1388 * This can cause completed packets to never get delivered if 1389 * their sequence numbers are all > MSEQ + 1. 1390 * 1391 * This routine checks how long all of the completed packets have 1392 * been sitting in the queue, and if too long, removes fragments 1393 * from the queue and increments MSEQ to allow them to be delivered. 1394 */ 1395static void 1396ng_ppp_frag_checkstale(node_p node) 1397{ 1398 const priv_p priv = NG_NODE_PRIVATE(node); 1399 struct ng_ppp_frag *qent, *beg, *end; 1400 struct timeval now, age; 1401 struct mbuf *m; 1402 meta_p meta; 1403 int i, seq; 1404 item_p item; 1405 1406 now.tv_sec = 0; /* uninitialized state */ 1407 while (1) { 1408 1409 /* If queue is empty, we're done */ 1410 if (TAILQ_EMPTY(&priv->frags)) 1411 break; 1412 1413 /* Find the first complete packet in the queue */ 1414 beg = end = NULL; 1415 seq = TAILQ_FIRST(&priv->frags)->seq; 1416 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1417 if (qent->first) 1418 beg = qent; 1419 else if (qent->seq != seq) 1420 beg = NULL; 1421 if (beg != NULL && qent->last) { 1422 end = qent; 1423 break; 1424 } 1425 seq = MP_NEXT_RECV_SEQ(priv, seq); 1426 } 1427 1428 /* If none found, exit */ 1429 if (end == NULL) 1430 break; 1431 1432 /* Get current time (we assume we've been up for >= 1 second) */ 1433 if (now.tv_sec == 0) 1434 getmicrouptime(&now); 1435 1436 /* Check if packet has been queued too long */ 1437 age = now; 1438 timevalsub(&age, &beg->timestamp); 1439 if (timevalcmp(&age, &ng_ppp_max_staleness, < )) 1440 break; 1441 1442 /* Throw away junk fragments in front of the completed packet */ 1443 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) { 1444 KASSERT(!TAILQ_EMPTY(&priv->frags), 1445 ("%s: empty q", __func__)); 1446 priv->bundleStats.dropFragments++; 1447 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1448 NG_FREE_M(qent->data); 1449 NG_FREE_META(qent->meta); 1450 FREE(qent, M_NETGRAPH_PPP); 1451 priv->qlen--; 1452 } 1453 1454 /* Extract completed packet */ 1455 ng_ppp_get_packet(node, &m, &meta); 1456 1457 /* Bump MSEQ if necessary */ 1458 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) { 1459 priv->mseq = end->seq; 1460 for (i = 0; i < priv->numActiveLinks; i++) { 1461 struct ng_ppp_link *const alink = 1462 &priv->links[priv->activeLinks[i]]; 1463 1464 if (MP_RECV_SEQ_DIFF(priv, 1465 alink->seq, priv->mseq) < 0) 1466 alink->seq = priv->mseq; 1467 } 1468 } 1469 1470 /* Deliver packet */ 1471 item = ng_package_data(m, meta); 1472 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1473 } 1474} 1475 1476/* 1477 * Periodically call ng_ppp_frag_checkstale() 1478 */ 1479static void 1480ng_ppp_frag_timeout(void *arg) 1481{ 1482 const node_p node = arg; 1483 const priv_p priv = NG_NODE_PRIVATE(node); 1484 int s = splnet(); 1485 1486 /* Handle the race where shutdown happens just before splnet() above */ 1487 if (NG_NODE_NOT_VALID(node)) { 1488 NG_NODE_UNREF(node); 1489 splx(s); 1490 return; 1491 } 1492 1493 /* Reset timer state after timeout */ 1494 KASSERT(priv->timerActive, ("%s: !timerActive", __func__)); 1495 priv->timerActive = 0; 1496 KASSERT(node->nd_refs > 1, ("%s: nd_refs=%d", __func__, node->nd_refs)); 1497 NG_NODE_UNREF(node); 1498 1499 /* Start timer again */ 1500 ng_ppp_start_frag_timer(node); 1501 1502 /* Scan the fragment queue */ 1503 ng_ppp_frag_checkstale(node); 1504 splx(s); 1505} 1506 1507/* 1508 * Deliver a frame out on the bundle, i.e., figure out how to fragment 1509 * the frame across the individual PPP links and do so. 1510 */ 1511static int 1512ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta) 1513{ 1514 const priv_p priv = NG_NODE_PRIVATE(node); 1515 int distrib[NG_PPP_MAX_LINKS]; 1516 int firstFragment; 1517 int activeLinkNum; 1518 item_p item; 1519 1520 /* At least one link must be active */ 1521 if (priv->numActiveLinks == 0) { 1522 NG_FREE_M(m); 1523 NG_FREE_META(meta); 1524 return (ENETDOWN); 1525 } 1526 1527 /* Round-robin strategy */ 1528 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) { 1529 activeLinkNum = priv->lastLink++ % priv->numActiveLinks; 1530 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0])); 1531 distrib[activeLinkNum] = m->m_pkthdr.len; 1532 goto deliver; 1533 } 1534 1535 /* Strategy when all links are equivalent (optimize the common case) */ 1536 if (priv->allLinksEqual) { 1537 const int fraction = m->m_pkthdr.len / priv->numActiveLinks; 1538 int i, remain; 1539 1540 for (i = 0; i < priv->numActiveLinks; i++) 1541 distrib[priv->lastLink++ % priv->numActiveLinks] 1542 = fraction; 1543 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks); 1544 while (remain > 0) { 1545 distrib[priv->lastLink++ % priv->numActiveLinks]++; 1546 remain--; 1547 } 1548 goto deliver; 1549 } 1550 1551 /* Strategy when all links are not equivalent */ 1552 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib); 1553 1554deliver: 1555 /* Update stats */ 1556 priv->bundleStats.xmitFrames++; 1557 priv->bundleStats.xmitOctets += m->m_pkthdr.len; 1558 1559 /* Send alloted portions of frame out on the link(s) */ 1560 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1; 1561 activeLinkNum >= 0; activeLinkNum--) { 1562 const int linkNum = priv->activeLinks[activeLinkNum]; 1563 struct ng_ppp_link *const link = &priv->links[linkNum]; 1564 1565 /* Deliver fragment(s) out the next link */ 1566 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) { 1567 int len, lastFragment, error; 1568 struct mbuf *m2; 1569 meta_p meta2; 1570 1571 /* Calculate fragment length; don't exceed link MTU */ 1572 len = distrib[activeLinkNum]; 1573 if (len > link->conf.mru) 1574 len = link->conf.mru; 1575 distrib[activeLinkNum] -= len; 1576 lastFragment = (len == m->m_pkthdr.len); 1577 1578 /* Split off next fragment as "m2" */ 1579 m2 = m; 1580 if (!lastFragment) { 1581 struct mbuf *n = m_split(m, len, M_NOWAIT); 1582 1583 if (n == NULL) { 1584 NG_FREE_M(m); 1585 NG_FREE_META(meta); 1586 return (ENOMEM); 1587 } 1588 m = n; 1589 } 1590 1591 /* Prepend MP header */ 1592 if (priv->conf.xmitShortSeq) { 1593 u_int16_t shdr; 1594 1595 shdr = priv->xseq; 1596 priv->xseq = 1597 (priv->xseq + 1) & MP_SHORT_SEQ_MASK; 1598 if (firstFragment) 1599 shdr |= MP_SHORT_FIRST_FLAG; 1600 if (lastFragment) 1601 shdr |= MP_SHORT_LAST_FLAG; 1602 shdr = htons(shdr); 1603 m2 = ng_ppp_prepend(m2, &shdr, 2); 1604 } else { 1605 u_int32_t lhdr; 1606 1607 lhdr = priv->xseq; 1608 priv->xseq = 1609 (priv->xseq + 1) & MP_LONG_SEQ_MASK; 1610 if (firstFragment) 1611 lhdr |= MP_LONG_FIRST_FLAG; 1612 if (lastFragment) 1613 lhdr |= MP_LONG_LAST_FLAG; 1614 lhdr = htonl(lhdr); 1615 m2 = ng_ppp_prepend(m2, &lhdr, 4); 1616 } 1617 if (m2 == NULL) { 1618 if (!lastFragment) 1619 m_freem(m); 1620 NG_FREE_META(meta); 1621 return (ENOBUFS); 1622 } 1623 1624 /* Copy the meta information, if any */ 1625 meta2 = lastFragment ? meta : ng_copy_meta(meta); 1626 1627 /* Send fragment */ 1628 item = ng_package_data(m2, meta2); 1629 error = ng_ppp_output(node, 0, PROT_MP, linkNum, item); 1630 if (error != 0) { 1631 if (!lastFragment) { 1632 NG_FREE_M(m); 1633 NG_FREE_META(meta); 1634 } 1635 return (error); 1636 } 1637 } 1638 } 1639 1640 /* Done */ 1641 return (0); 1642} 1643 1644/* 1645 * Computing the optimal fragmentation 1646 * ----------------------------------- 1647 * 1648 * This routine tries to compute the optimal fragmentation pattern based 1649 * on each link's latency, bandwidth, and calculated additional latency. 1650 * The latter quantity is the additional latency caused by previously 1651 * written data that has not been transmitted yet. 1652 * 1653 * This algorithm is only useful when not all of the links have the 1654 * same latency and bandwidth values. 1655 * 1656 * The essential idea is to make the last bit of each fragment of the 1657 * frame arrive at the opposite end at the exact same time. This greedy 1658 * algorithm is optimal, in that no other scheduling could result in any 1659 * packet arriving any sooner unless packets are delivered out of order. 1660 * 1661 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and 1662 * latency l_i (in miliseconds). Consider the function function f_i(t) 1663 * which is equal to the number of bytes that will have arrived at 1664 * the peer after t miliseconds if we start writing continuously at 1665 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i). 1666 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i). 1667 * Note that the y-intersect is always <= zero because latency can't be 1668 * negative. Note also that really the function is f_i(t) except when 1669 * f_i(t) is negative, in which case the function is zero. To take 1670 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }. 1671 * So the actual number of bytes that will have arrived at the peer after 1672 * t miliseconds is f_i(t) * Q_i(t). 1673 * 1674 * At any given time, each link has some additional latency a_i >= 0 1675 * due to previously written fragment(s) which are still in the queue. 1676 * This value is easily computed from the time since last transmission, 1677 * the previous latency value, the number of bytes written, and the 1678 * link's bandwidth. 1679 * 1680 * Assume that l_i includes any a_i already, and that the links are 1681 * sorted by latency, so that l_i <= l_{i+1}. 1682 * 1683 * Let N be the total number of bytes in the current frame we are sending. 1684 * 1685 * Suppose we were to start writing bytes at time t = 0 on all links 1686 * simultaneously, which is the most we can possibly do. Then let 1687 * F(t) be equal to the total number of bytes received by the peer 1688 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)). 1689 * 1690 * Our goal is simply this: fragment the frame across the links such 1691 * that the peer is able to reconstruct the completed frame as soon as 1692 * possible, i.e., at the least possible value of t. Call this value t_0. 1693 * 1694 * Then it follows that F(t_0) = N. Our strategy is first to find the value 1695 * of t_0, and then deduce how many bytes to write to each link. 1696 * 1697 * Rewriting F(t_0): 1698 * 1699 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) ) 1700 * 1701 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will 1702 * lie in one of these ranges. To find it, we just need to find the i such 1703 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values 1704 * for Q_i() in this range, plug in the remaining values, solving for t_0. 1705 * 1706 * Once t_0 is known, then the number of bytes to send on link i is 1707 * just f_i(t_0) * Q_i(t_0). 1708 * 1709 * In other words, we start allocating bytes to the links one at a time. 1710 * We keep adding links until the frame is completely sent. Some links 1711 * may not get any bytes because their latency is too high. 1712 * 1713 * Is all this work really worth the trouble? Depends on the situation. 1714 * The bigger the ratio of computer speed to link speed, and the more 1715 * important total bundle latency is (e.g., for interactive response time), 1716 * the more it's worth it. There is however the cost of calling this 1717 * function for every frame. The running time is O(n^2) where n is the 1718 * number of links that receive a non-zero number of bytes. 1719 * 1720 * Since latency is measured in miliseconds, the "resolution" of this 1721 * algorithm is one milisecond. 1722 * 1723 * To avoid this algorithm altogether, configure all links to have the 1724 * same latency and bandwidth. 1725 */ 1726static void 1727ng_ppp_mp_strategy(node_p node, int len, int *distrib) 1728{ 1729 const priv_p priv = NG_NODE_PRIVATE(node); 1730 int latency[NG_PPP_MAX_LINKS]; 1731 int sortByLatency[NG_PPP_MAX_LINKS]; 1732 int activeLinkNum; 1733 int t0, total, topSum, botSum; 1734 struct timeval now; 1735 int i, numFragments; 1736 1737 /* If only one link, this gets real easy */ 1738 if (priv->numActiveLinks == 1) { 1739 distrib[0] = len; 1740 return; 1741 } 1742 1743 /* Get current time */ 1744 getmicrouptime(&now); 1745 1746 /* Compute latencies for each link at this point in time */ 1747 for (activeLinkNum = 0; 1748 activeLinkNum < priv->numActiveLinks; activeLinkNum++) { 1749 struct ng_ppp_link *alink; 1750 struct timeval diff; 1751 int xmitBytes; 1752 1753 /* Start with base latency value */ 1754 alink = &priv->links[priv->activeLinks[activeLinkNum]]; 1755 latency[activeLinkNum] = alink->conf.latency; 1756 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */ 1757 1758 /* Any additional latency? */ 1759 if (alink->bytesInQueue == 0) 1760 continue; 1761 1762 /* Compute time delta since last write */ 1763 diff = now; 1764 timevalsub(&diff, &alink->lastWrite); 1765 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */ 1766 alink->bytesInQueue = 0; 1767 continue; 1768 } 1769 1770 /* How many bytes could have transmitted since last write? */ 1771 xmitBytes = (alink->conf.bandwidth * diff.tv_sec) 1772 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100; 1773 alink->bytesInQueue -= xmitBytes; 1774 if (alink->bytesInQueue < 0) 1775 alink->bytesInQueue = 0; 1776 else 1777 latency[activeLinkNum] += 1778 (100 * alink->bytesInQueue) / alink->conf.bandwidth; 1779 } 1780 1781 /* Sort active links by latency */ 1782 compareLatencies = latency; 1783 qsort(sortByLatency, 1784 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp); 1785 compareLatencies = NULL; 1786 1787 /* Find the interval we need (add links in sortByLatency[] order) */ 1788 for (numFragments = 1; 1789 numFragments < priv->numActiveLinks; numFragments++) { 1790 for (total = i = 0; i < numFragments; i++) { 1791 int flowTime; 1792 1793 flowTime = latency[sortByLatency[numFragments]] 1794 - latency[sortByLatency[i]]; 1795 total += ((flowTime * priv->links[ 1796 priv->activeLinks[sortByLatency[i]]].conf.bandwidth) 1797 + 99) / 100; 1798 } 1799 if (total >= len) 1800 break; 1801 } 1802 1803 /* Solve for t_0 in that interval */ 1804 for (topSum = botSum = i = 0; i < numFragments; i++) { 1805 int bw = priv->links[ 1806 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1807 1808 topSum += latency[sortByLatency[i]] * bw; /* / 100 */ 1809 botSum += bw; /* / 100 */ 1810 } 1811 t0 = ((len * 100) + topSum + botSum / 2) / botSum; 1812 1813 /* Compute f_i(t_0) all i */ 1814 bzero(distrib, priv->numActiveLinks * sizeof(*distrib)); 1815 for (total = i = 0; i < numFragments; i++) { 1816 int bw = priv->links[ 1817 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1818 1819 distrib[sortByLatency[i]] = 1820 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100; 1821 total += distrib[sortByLatency[i]]; 1822 } 1823 1824 /* Deal with any rounding error */ 1825 if (total < len) { 1826 struct ng_ppp_link *fastLink = 1827 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1828 int fast = 0; 1829 1830 /* Find the fastest link */ 1831 for (i = 1; i < numFragments; i++) { 1832 struct ng_ppp_link *const link = 1833 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1834 1835 if (link->conf.bandwidth > fastLink->conf.bandwidth) { 1836 fast = i; 1837 fastLink = link; 1838 } 1839 } 1840 distrib[sortByLatency[fast]] += len - total; 1841 } else while (total > len) { 1842 struct ng_ppp_link *slowLink = 1843 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1844 int delta, slow = 0; 1845 1846 /* Find the slowest link that still has bytes to remove */ 1847 for (i = 1; i < numFragments; i++) { 1848 struct ng_ppp_link *const link = 1849 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1850 1851 if (distrib[sortByLatency[slow]] == 0 1852 || (distrib[sortByLatency[i]] > 0 1853 && link->conf.bandwidth < 1854 slowLink->conf.bandwidth)) { 1855 slow = i; 1856 slowLink = link; 1857 } 1858 } 1859 delta = total - len; 1860 if (delta > distrib[sortByLatency[slow]]) 1861 delta = distrib[sortByLatency[slow]]; 1862 distrib[sortByLatency[slow]] -= delta; 1863 total -= delta; 1864 } 1865} 1866 1867/* 1868 * Compare two integers 1869 */ 1870static int 1871ng_ppp_intcmp(const void *v1, const void *v2) 1872{ 1873 const int index1 = *((const int *) v1); 1874 const int index2 = *((const int *) v2); 1875 1876 return compareLatencies[index1] - compareLatencies[index2]; 1877} 1878 1879/* 1880 * Prepend a possibly compressed PPP protocol number in front of a frame 1881 */ 1882static struct mbuf * 1883ng_ppp_addproto(struct mbuf *m, int proto, int compOK) 1884{ 1885 if (compOK && PROT_COMPRESSABLE(proto)) { 1886 u_char pbyte = (u_char)proto; 1887 1888 return ng_ppp_prepend(m, &pbyte, 1); 1889 } else { 1890 u_int16_t pword = htons((u_int16_t)proto); 1891 1892 return ng_ppp_prepend(m, &pword, 2); 1893 } 1894} 1895 1896/* 1897 * Prepend some bytes to an mbuf 1898 */ 1899static struct mbuf * 1900ng_ppp_prepend(struct mbuf *m, const void *buf, int len) 1901{ 1902 M_PREPEND(m, len, M_NOWAIT); 1903 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL)) 1904 return (NULL); 1905 bcopy(buf, mtod(m, u_char *), len); 1906 return (m); 1907} 1908 1909/* 1910 * Update private information that is derived from other private information 1911 */ 1912static void 1913ng_ppp_update(node_p node, int newConf) 1914{ 1915 const priv_p priv = NG_NODE_PRIVATE(node); 1916 int i; 1917 1918 /* Update active status for VJ Compression */ 1919 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL 1920 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL 1921 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL 1922 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL; 1923 1924 /* Increase latency for each link an amount equal to one MP header */ 1925 if (newConf) { 1926 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1927 int hdrBytes; 1928 1929 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2) 1930 + (priv->links[i].conf.enableProtoComp ? 1 : 2) 1931 + (priv->conf.xmitShortSeq ? 2 : 4); 1932 priv->links[i].conf.latency += 1933 ((hdrBytes * priv->links[i].conf.bandwidth) + 50) 1934 / 100; 1935 } 1936 } 1937 1938 /* Update list of active links */ 1939 bzero(&priv->activeLinks, sizeof(priv->activeLinks)); 1940 priv->numActiveLinks = 0; 1941 priv->allLinksEqual = 1; 1942 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1943 struct ng_ppp_link *const link = &priv->links[i]; 1944 1945 /* Is link active? */ 1946 if (link->conf.enableLink && link->hook != NULL) { 1947 struct ng_ppp_link *link0; 1948 1949 /* Add link to list of active links */ 1950 priv->activeLinks[priv->numActiveLinks++] = i; 1951 link0 = &priv->links[priv->activeLinks[0]]; 1952 1953 /* Determine if all links are still equal */ 1954 if (link->conf.latency != link0->conf.latency 1955 || link->conf.bandwidth != link0->conf.bandwidth) 1956 priv->allLinksEqual = 0; 1957 1958 /* Initialize rec'd sequence number */ 1959 if (link->seq == MP_NOSEQ) { 1960 link->seq = (link == link0) ? 1961 MP_INITIAL_SEQ : link0->seq; 1962 } 1963 } else 1964 link->seq = MP_NOSEQ; 1965 } 1966 1967 /* Update MP state as multi-link is active or not */ 1968 if (priv->conf.enableMultilink && priv->numActiveLinks > 0) 1969 ng_ppp_start_frag_timer(node); 1970 else { 1971 ng_ppp_stop_frag_timer(node); 1972 ng_ppp_frag_reset(node); 1973 priv->xseq = MP_INITIAL_SEQ; 1974 priv->mseq = MP_INITIAL_SEQ; 1975 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1976 struct ng_ppp_link *const link = &priv->links[i]; 1977 1978 bzero(&link->lastWrite, sizeof(link->lastWrite)); 1979 link->bytesInQueue = 0; 1980 link->seq = MP_NOSEQ; 1981 } 1982 } 1983} 1984 1985/* 1986 * Determine if a new configuration would represent a valid change 1987 * from the current configuration and link activity status. 1988 */ 1989static int 1990ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf) 1991{ 1992 const priv_p priv = NG_NODE_PRIVATE(node); 1993 int i, newNumLinksActive; 1994 1995 /* Check per-link config and count how many links would be active */ 1996 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) { 1997 if (newConf->links[i].enableLink && priv->links[i].hook != NULL) 1998 newNumLinksActive++; 1999 if (!newConf->links[i].enableLink) 2000 continue; 2001 if (newConf->links[i].mru < MP_MIN_LINK_MRU) 2002 return (0); 2003 if (newConf->links[i].bandwidth == 0) 2004 return (0); 2005 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH) 2006 return (0); 2007 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY) 2008 return (0); 2009 } 2010 2011 /* Check bundle parameters */ 2012 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU) 2013 return (0); 2014 2015 /* Disallow changes to multi-link configuration while MP is active */ 2016 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) { 2017 if (!priv->conf.enableMultilink 2018 != !newConf->bund.enableMultilink 2019 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq 2020 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq) 2021 return (0); 2022 } 2023 2024 /* At most one link can be active unless multi-link is enabled */ 2025 if (!newConf->bund.enableMultilink && newNumLinksActive > 1) 2026 return (0); 2027 2028 /* Configuration change would be valid */ 2029 return (1); 2030} 2031 2032/* 2033 * Free all entries in the fragment queue 2034 */ 2035static void 2036ng_ppp_frag_reset(node_p node) 2037{ 2038 const priv_p priv = NG_NODE_PRIVATE(node); 2039 struct ng_ppp_frag *qent, *qnext; 2040 2041 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) { 2042 qnext = TAILQ_NEXT(qent, f_qent); 2043 NG_FREE_M(qent->data); 2044 NG_FREE_META(qent->meta); 2045 FREE(qent, M_NETGRAPH_PPP); 2046 } 2047 TAILQ_INIT(&priv->frags); 2048 priv->qlen = 0; 2049} 2050 2051/* 2052 * Start fragment queue timer 2053 */ 2054static void 2055ng_ppp_start_frag_timer(node_p node) 2056{ 2057 const priv_p priv = NG_NODE_PRIVATE(node); 2058 2059 if (!priv->timerActive) { 2060 priv->fragTimer = timeout(ng_ppp_frag_timeout, 2061 node, MP_FRAGTIMER_INTERVAL); 2062 priv->timerActive = 1; 2063 NG_NODE_REF(node); 2064 } 2065} 2066 2067/* 2068 * Stop fragment queue timer 2069 */ 2070static void 2071ng_ppp_stop_frag_timer(node_p node) 2072{ 2073 const priv_p priv = NG_NODE_PRIVATE(node); 2074 2075 if (priv->timerActive) { 2076 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer); 2077 priv->timerActive = 0; 2078 KASSERT(node->nd_refs > 1, 2079 ("%s: nd_refs=%d", __func__, node->nd_refs)); 2080 NG_NODE_UNREF(node); 2081 } 2082} 2083 2084