1 2 /* 3 * ng_ppp.c 4 * 5 * Copyright (c) 1996-2000 Whistle Communications, Inc. 6 * All rights reserved. 7 * 8 * Subject to the following obligations and disclaimer of warranty, use and 9 * redistribution of this software, in source or object code forms, with or 10 * without modifications are expressly permitted by Whistle Communications; 11 * provided, however, that: 12 * 1. Any and all reproductions of the source or object code must include the 13 * copyright notice above and the following disclaimer of warranties; and 14 * 2. No rights are granted, in any manner or form, to use Whistle 15 * Communications, Inc. trademarks, including the mark "WHISTLE 16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 17 * such appears in the above copyright notice or in the software. 18 * 19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 35 * OF SUCH DAMAGE. 36 * 37 * Author: Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $ 41 */ 42 43 /* 44 * PPP node type. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/time.h> 51 #include <sys/mbuf.h> 52 #include <sys/malloc.h> 53 #include <sys/errno.h> 54 #include <sys/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 65 MALLOC_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 */ 136 struct 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 */ 147 static 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. 181 XXX Not any more.. (what a hack) 182 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private)) 183 */ 184 185 /* Per-link private information */ 186 struct 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 */ 196 struct 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 }; 214 typedef struct ng_ppp_private *priv_p; 215 216 /* Netgraph node methods */ 217 static ng_constructor_t ng_ppp_constructor; 218 static ng_rcvmsg_t ng_ppp_rcvmsg; 219 static ng_shutdown_t ng_ppp_shutdown; 220 static ng_newhook_t ng_ppp_newhook; 221 static ng_rcvdata_t ng_ppp_rcvdata; 222 static ng_disconnect_t ng_ppp_disconnect; 223 224 /* Helper functions */ 225 static int ng_ppp_input(node_p node, int bypass, 226 int linkNum, item_p item); 227 static int ng_ppp_output(node_p node, int bypass, int proto, 228 int linkNum, item_p item); 229 static int ng_ppp_mp_input(node_p node, int linkNum, item_p item); 230 static int ng_ppp_check_packet(node_p node); 231 static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap); 232 static int ng_ppp_frag_process(node_p node); 233 static int ng_ppp_frag_trim(node_p node); 234 static void ng_ppp_frag_timeout(void *arg); 235 static void ng_ppp_frag_checkstale(node_p node); 236 static void ng_ppp_frag_reset(node_p node); 237 static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta); 238 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib); 239 static int ng_ppp_intcmp(const void *v1, const void *v2); 240 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK); 241 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len); 242 static int ng_ppp_config_valid(node_p node, 243 const struct ng_ppp_node_conf *newConf); 244 static void ng_ppp_update(node_p node, int newConf); 245 static void ng_ppp_start_frag_timer(node_p node); 246 static void ng_ppp_stop_frag_timer(node_p node); 247 248 /* Parse type for struct ng_ppp_mp_state_type */ 249 static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = { 250 &ng_parse_hint32_type, 251 NG_PPP_MAX_LINKS 252 }; 253 static const struct ng_parse_type ng_ppp_rseq_array_type = { 254 &ng_parse_fixedarray_type, 255 &ng_ppp_rseq_array_info, 256 }; 257 static const struct ng_parse_struct_info ng_ppp_mp_state_type_info 258 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type); 259 static const struct ng_parse_type ng_ppp_mp_state_type = { 260 &ng_parse_struct_type, 261 &ng_ppp_mp_state_type_info, 262 }; 263 264 /* Parse type for struct ng_ppp_link_conf */ 265 static const struct ng_parse_struct_info 266 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO; 267 static const struct ng_parse_type ng_ppp_link_type = { 268 &ng_parse_struct_type, 269 &ng_ppp_link_type_info, 270 }; 271 272 /* Parse type for struct ng_ppp_bund_conf */ 273 static const struct ng_parse_struct_info 274 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO; 275 static const struct ng_parse_type ng_ppp_bund_type = { 276 &ng_parse_struct_type, 277 &ng_ppp_bund_type_info, 278 }; 279 280 /* Parse type for struct ng_ppp_node_conf */ 281 static const struct ng_parse_fixedarray_info ng_ppp_array_info = { 282 &ng_ppp_link_type, 283 NG_PPP_MAX_LINKS 284 }; 285 static const struct ng_parse_type ng_ppp_link_array_type = { 286 &ng_parse_fixedarray_type, 287 &ng_ppp_array_info, 288 }; 289 static const struct ng_parse_struct_info ng_ppp_conf_type_info 290 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type); 291 static const struct ng_parse_type ng_ppp_conf_type = { 292 &ng_parse_struct_type, 293 &ng_ppp_conf_type_info 294 }; 295 296 /* Parse type for struct ng_ppp_link_stat */ 297 static const struct ng_parse_struct_info 298 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO; 299 static const struct ng_parse_type ng_ppp_stats_type = { 300 &ng_parse_struct_type, 301 &ng_ppp_stats_type_info 302 }; 303 304 /* List of commands and how to convert arguments to/from ASCII */ 305 static 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 */ 352 static 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 }; 366 NETGRAPH_INIT(ppp, &ng_ppp_typestruct); 367 368 static int *compareLatencies; /* hack for ng_ppp_intcmp() */ 369 370 /* Address and control field header */ 371 static const u_char ng_ppp_acf[2] = { 0xff, 0x03 }; 372 373 /* Maximum time we'll let a complete incoming packet sit in the queue */ 374 static 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 */ 385 static int 386 ng_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 */ 411 static int 412 ng_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 *)hookIndex); 459 ng_ppp_update(node, 0); 460 return (0); 461 } 462 463 /* 464 * Receive a control message 465 */ 466 static int 467 ng_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 } 582 done: 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 */ 591 static int 592 ng_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 = (int)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 */ 804 static int 805 ng_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 */ 824 static int 825 ng_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 = (int)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 */ 856 static int 857 ng_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 return ng_ppp_mp_input(node, linkNum, item); 911 break; 912 case PROT_APPLETALK: 913 if (priv->conf.enableAtalk) 914 outHook = priv->hooks[HOOK_INDEX_ATALK]; 915 break; 916 case PROT_IPX: 917 if (priv->conf.enableIPX) 918 outHook = priv->hooks[HOOK_INDEX_IPX]; 919 break; 920 case PROT_IP: 921 if (priv->conf.enableIP) 922 outHook = priv->hooks[HOOK_INDEX_INET]; 923 break; 924 case PROT_IPV6: 925 if (priv->conf.enableIPv6) 926 outHook = priv->hooks[HOOK_INDEX_IPV6]; 927 break; 928 } 929 930 bypass: 931 /* For unknown/inactive protocols, forward out the bypass hook */ 932 if (outHook == NULL) { 933 u_int16_t hdr[2]; 934 935 hdr[0] = htons(linkNum); 936 hdr[1] = htons((u_int16_t)proto); 937 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) { 938 NG_FREE_ITEM(item); 939 return (ENOBUFS); 940 } 941 outHook = priv->hooks[HOOK_INDEX_BYPASS]; 942 } 943 944 /* Forward frame */ 945 NG_FWD_NEW_DATA(error, item, outHook, m); 946 return (error); 947 } 948 949 /* 950 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM. 951 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0. 952 * 953 * If the frame is too big for the particular link, return EMSGSIZE. 954 */ 955 static int 956 ng_ppp_output(node_p node, int bypass, 957 int proto, int linkNum, item_p item) 958 { 959 const priv_p priv = NG_NODE_PRIVATE(node); 960 struct ng_ppp_link *link; 961 int len, error; 962 struct mbuf *m; 963 u_int16_t mru; 964 965 /* Extract mbuf */ 966 NGI_GET_M(item, m); 967 968 /* If not doing MP, map bundle virtual link to (the only) link */ 969 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink) 970 linkNum = priv->activeLinks[0]; 971 972 /* Get link pointer (optimization) */ 973 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ? 974 &priv->links[linkNum] : NULL; 975 976 /* Check link status (if real) */ 977 if (linkNum != NG_PPP_BUNDLE_LINKNUM) { 978 if (!bypass && !link->conf.enableLink) { 979 NG_FREE_M(m); 980 NG_FREE_ITEM(item); 981 return (ENXIO); 982 } 983 if (link->hook == NULL) { 984 NG_FREE_M(m); 985 NG_FREE_ITEM(item); 986 return (ENETDOWN); 987 } 988 } 989 990 /* Check peer's MRU for this link */ 991 mru = (link != NULL) ? link->conf.mru : priv->conf.mrru; 992 if (mru != 0 && m->m_pkthdr.len > mru) { 993 NG_FREE_M(m); 994 NG_FREE_ITEM(item); 995 return (EMSGSIZE); 996 } 997 998 /* Prepend protocol number, possibly compressed */ 999 if ((m = ng_ppp_addproto(m, proto, 1000 linkNum == NG_PPP_BUNDLE_LINKNUM 1001 || link->conf.enableProtoComp)) == NULL) { 1002 NG_FREE_ITEM(item); 1003 return (ENOBUFS); 1004 } 1005 1006 /* Special handling for the MP virtual link */ 1007 if (linkNum == NG_PPP_BUNDLE_LINKNUM) { 1008 meta_p meta; 1009 1010 /* strip off and discard the queue item */ 1011 NGI_GET_META(item, meta); 1012 NG_FREE_ITEM(item); 1013 return ng_ppp_mp_output(node, m, meta); 1014 } 1015 1016 /* Prepend address and control field (unless compressed) */ 1017 if (proto == PROT_LCP || !link->conf.enableACFComp) { 1018 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) { 1019 NG_FREE_ITEM(item); 1020 return (ENOBUFS); 1021 } 1022 } 1023 1024 /* Deliver frame */ 1025 len = m->m_pkthdr.len; 1026 NG_FWD_NEW_DATA(error, item, link->hook, m); 1027 1028 /* Update stats and 'bytes in queue' counter */ 1029 if (error == 0) { 1030 link->stats.xmitFrames++; 1031 link->stats.xmitOctets += len; 1032 link->bytesInQueue += len; 1033 getmicrouptime(&link->lastWrite); 1034 } 1035 return error; 1036 } 1037 1038 /* 1039 * Handle an incoming multi-link fragment 1040 * 1041 * The fragment reassembly algorithm is somewhat complex. This is mainly 1042 * because we are required not to reorder the reconstructed packets, yet 1043 * fragments are only guaranteed to arrive in order on a per-link basis. 1044 * In other words, when we have a complete packet ready, but the previous 1045 * packet is still incomplete, we have to decide between delivering the 1046 * complete packet and throwing away the incomplete one, or waiting to 1047 * see if the remainder of the incomplete one arrives, at which time we 1048 * can deliver both packets, in order. 1049 * 1050 * This problem is exacerbated by "sequence number slew", which is when 1051 * the sequence numbers coming in from different links are far apart from 1052 * each other. In particular, certain unnamed equipment (*cough* Ascend) 1053 * has been seen to generate sequence number slew of up to 10 on an ISDN 1054 * 2B-channel MP link. There is nothing invalid about sequence number slew 1055 * but it makes the reasssembly process have to work harder. 1056 * 1057 * However, the peer is required to transmit fragments in order on each 1058 * link. That means if we define MSEQ as the minimum over all links of 1059 * the highest sequence number received on that link, then we can always 1060 * give up any hope of receiving a fragment with sequence number < MSEQ in 1061 * the future (all of this using 'wraparound' sequence number space). 1062 * Therefore we can always immediately throw away incomplete packets 1063 * missing fragments with sequence numbers < MSEQ. 1064 * 1065 * Here is an overview of our algorithm: 1066 * 1067 * o Received fragments are inserted into a queue, for which we 1068 * maintain these invariants between calls to this function: 1069 * 1070 * - Fragments are ordered in the queue by sequence number 1071 * - If a complete packet is at the head of the queue, then 1072 * the first fragment in the packet has seq# > MSEQ + 1 1073 * (otherwise, we could deliver it immediately) 1074 * - If any fragments have seq# < MSEQ, then they are necessarily 1075 * part of a packet whose missing seq#'s are all > MSEQ (otherwise, 1076 * we can throw them away because they'll never be completed) 1077 * - The queue contains at most MP_MAX_QUEUE_LEN fragments 1078 * 1079 * o We have a periodic timer that checks the queue for the first 1080 * complete packet that has been sitting in the queue "too long". 1081 * When one is detected, all previous (incomplete) fragments are 1082 * discarded, their missing fragments are declared lost and MSEQ 1083 * is increased. 1084 * 1085 * o If we recieve a fragment with seq# < MSEQ, we throw it away 1086 * because we've already delcared it lost. 1087 * 1088 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM. 1089 */ 1090 static int 1091 ng_ppp_mp_input(node_p node, int linkNum, item_p item) 1092 { 1093 const priv_p priv = NG_NODE_PRIVATE(node); 1094 struct ng_ppp_link *const link = &priv->links[linkNum]; 1095 struct ng_ppp_frag frag0, *frag = &frag0; 1096 struct ng_ppp_frag *qent; 1097 int i, diff, inserted; 1098 struct mbuf *m; 1099 meta_p meta; 1100 1101 NGI_GET_M(item, m); 1102 NGI_GET_META(item, meta); 1103 NG_FREE_ITEM(item); 1104 /* Stats */ 1105 priv->bundleStats.recvFrames++; 1106 priv->bundleStats.recvOctets += m->m_pkthdr.len; 1107 1108 /* Extract fragment information from MP header */ 1109 if (priv->conf.recvShortSeq) { 1110 u_int16_t shdr; 1111 1112 if (m->m_pkthdr.len < 2) { 1113 link->stats.runts++; 1114 NG_FREE_M(m); 1115 NG_FREE_META(meta); 1116 return (EINVAL); 1117 } 1118 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 1119 NG_FREE_META(meta); 1120 return (ENOBUFS); 1121 } 1122 shdr = ntohs(*mtod(m, u_int16_t *)); 1123 frag->seq = MP_SHORT_EXTEND(shdr); 1124 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0; 1125 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0; 1126 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq); 1127 m_adj(m, 2); 1128 } else { 1129 u_int32_t lhdr; 1130 1131 if (m->m_pkthdr.len < 4) { 1132 link->stats.runts++; 1133 NG_FREE_M(m); 1134 NG_FREE_META(meta); 1135 return (EINVAL); 1136 } 1137 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 1138 NG_FREE_META(meta); 1139 return (ENOBUFS); 1140 } 1141 lhdr = ntohl(*mtod(m, u_int32_t *)); 1142 frag->seq = MP_LONG_EXTEND(lhdr); 1143 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0; 1144 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0; 1145 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq); 1146 m_adj(m, 4); 1147 } 1148 frag->data = m; 1149 frag->meta = meta; 1150 getmicrouptime(&frag->timestamp); 1151 1152 /* If sequence number is < MSEQ, we've already declared this 1153 fragment as lost, so we have no choice now but to drop it */ 1154 if (diff < 0) { 1155 link->stats.dropFragments++; 1156 NG_FREE_M(m); 1157 NG_FREE_META(meta); 1158 return (0); 1159 } 1160 1161 /* Update highest received sequence number on this link and MSEQ */ 1162 priv->mseq = link->seq = frag->seq; 1163 for (i = 0; i < priv->numActiveLinks; i++) { 1164 struct ng_ppp_link *const alink = 1165 &priv->links[priv->activeLinks[i]]; 1166 1167 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0) 1168 priv->mseq = alink->seq; 1169 } 1170 1171 /* Allocate a new frag struct for the queue */ 1172 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH_PPP, M_NOWAIT); 1173 if (frag == NULL) { 1174 NG_FREE_M(m); 1175 NG_FREE_META(meta); 1176 ng_ppp_frag_process(node); 1177 return (ENOMEM); 1178 } 1179 *frag = frag0; 1180 1181 /* Add fragment to queue, which is sorted by sequence number */ 1182 inserted = 0; 1183 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) { 1184 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq); 1185 if (diff > 0) { 1186 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent); 1187 inserted = 1; 1188 break; 1189 } else if (diff == 0) { /* should never happen! */ 1190 link->stats.dupFragments++; 1191 NG_FREE_M(frag->data); 1192 NG_FREE_META(frag->meta); 1193 FREE(frag, M_NETGRAPH_PPP); 1194 return (EINVAL); 1195 } 1196 } 1197 if (!inserted) 1198 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent); 1199 priv->qlen++; 1200 1201 /* Process the queue */ 1202 return ng_ppp_frag_process(node); 1203 } 1204 1205 /* 1206 * Examine our list of fragments, and determine if there is a 1207 * complete and deliverable packet at the head of the list. 1208 * Return 1 if so, zero otherwise. 1209 */ 1210 static int 1211 ng_ppp_check_packet(node_p node) 1212 { 1213 const priv_p priv = NG_NODE_PRIVATE(node); 1214 struct ng_ppp_frag *qent, *qnext; 1215 1216 /* Check for empty queue */ 1217 if (TAILQ_EMPTY(&priv->frags)) 1218 return (0); 1219 1220 /* Check first fragment is the start of a deliverable packet */ 1221 qent = TAILQ_FIRST(&priv->frags); 1222 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1) 1223 return (0); 1224 1225 /* Check that all the fragments are there */ 1226 while (!qent->last) { 1227 qnext = TAILQ_NEXT(qent, f_qent); 1228 if (qnext == NULL) /* end of queue */ 1229 return (0); 1230 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)) 1231 return (0); 1232 qent = qnext; 1233 } 1234 1235 /* Got one */ 1236 return (1); 1237 } 1238 1239 /* 1240 * Pull a completed packet off the head of the incoming fragment queue. 1241 * This assumes there is a completed packet there to pull off. 1242 */ 1243 static void 1244 ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap) 1245 { 1246 const priv_p priv = NG_NODE_PRIVATE(node); 1247 struct ng_ppp_frag *qent, *qnext; 1248 struct mbuf *m = NULL, *tail; 1249 1250 qent = TAILQ_FIRST(&priv->frags); 1251 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first, 1252 ("%s: no packet", __func__)); 1253 for (tail = NULL; qent != NULL; qent = qnext) { 1254 qnext = TAILQ_NEXT(qent, f_qent); 1255 KASSERT(!TAILQ_EMPTY(&priv->frags), 1256 ("%s: empty q", __func__)); 1257 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1258 if (tail == NULL) { 1259 tail = m = qent->data; 1260 *metap = qent->meta; /* inherit first frag's meta */ 1261 } else { 1262 m->m_pkthdr.len += qent->data->m_pkthdr.len; 1263 tail->m_next = qent->data; 1264 NG_FREE_META(qent->meta); /* drop other frags' metas */ 1265 } 1266 while (tail->m_next != NULL) 1267 tail = tail->m_next; 1268 if (qent->last) 1269 qnext = NULL; 1270 FREE(qent, M_NETGRAPH_PPP); 1271 priv->qlen--; 1272 } 1273 *mp = m; 1274 } 1275 1276 /* 1277 * Trim fragments from the queue whose packets can never be completed. 1278 * This assumes a complete packet is NOT at the beginning of the queue. 1279 * Returns 1 if fragments were removed, zero otherwise. 1280 */ 1281 static int 1282 ng_ppp_frag_trim(node_p node) 1283 { 1284 const priv_p priv = NG_NODE_PRIVATE(node); 1285 struct ng_ppp_frag *qent, *qnext = NULL; 1286 int removed = 0; 1287 1288 /* Scan for "dead" fragments and remove them */ 1289 while (1) { 1290 int dead = 0; 1291 1292 /* If queue is empty, we're done */ 1293 if (TAILQ_EMPTY(&priv->frags)) 1294 break; 1295 1296 /* Determine whether first fragment can ever be completed */ 1297 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1298 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0) 1299 break; 1300 qnext = TAILQ_NEXT(qent, f_qent); 1301 KASSERT(qnext != NULL, 1302 ("%s: last frag < MSEQ?", __func__)); 1303 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq) 1304 || qent->last || qnext->first) { 1305 dead = 1; 1306 break; 1307 } 1308 } 1309 if (!dead) 1310 break; 1311 1312 /* Remove fragment and all others in the same packet */ 1313 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) { 1314 KASSERT(!TAILQ_EMPTY(&priv->frags), 1315 ("%s: empty q", __func__)); 1316 priv->bundleStats.dropFragments++; 1317 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1318 NG_FREE_M(qent->data); 1319 NG_FREE_META(qent->meta); 1320 FREE(qent, M_NETGRAPH_PPP); 1321 priv->qlen--; 1322 removed = 1; 1323 } 1324 } 1325 return (removed); 1326 } 1327 1328 /* 1329 * Run the queue, restoring the queue invariants 1330 */ 1331 static int 1332 ng_ppp_frag_process(node_p node) 1333 { 1334 const priv_p priv = NG_NODE_PRIVATE(node); 1335 struct mbuf *m; 1336 meta_p meta; 1337 item_p item; 1338 1339 /* Deliver any deliverable packets */ 1340 while (ng_ppp_check_packet(node)) { 1341 ng_ppp_get_packet(node, &m, &meta); 1342 item = ng_package_data(m, meta); 1343 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1344 } 1345 1346 /* Delete dead fragments and try again */ 1347 if (ng_ppp_frag_trim(node)) { 1348 while (ng_ppp_check_packet(node)) { 1349 ng_ppp_get_packet(node, &m, &meta); 1350 item = ng_package_data(m, meta); 1351 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1352 } 1353 } 1354 1355 /* Check for stale fragments while we're here */ 1356 ng_ppp_frag_checkstale(node); 1357 1358 /* Check queue length */ 1359 if (priv->qlen > MP_MAX_QUEUE_LEN) { 1360 struct ng_ppp_frag *qent; 1361 int i; 1362 1363 /* Get oldest fragment */ 1364 KASSERT(!TAILQ_EMPTY(&priv->frags), 1365 ("%s: empty q", __func__)); 1366 qent = TAILQ_FIRST(&priv->frags); 1367 1368 /* Bump MSEQ if necessary */ 1369 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) { 1370 priv->mseq = qent->seq; 1371 for (i = 0; i < priv->numActiveLinks; i++) { 1372 struct ng_ppp_link *const alink = 1373 &priv->links[priv->activeLinks[i]]; 1374 1375 if (MP_RECV_SEQ_DIFF(priv, 1376 alink->seq, priv->mseq) < 0) 1377 alink->seq = priv->mseq; 1378 } 1379 } 1380 1381 /* Drop it */ 1382 priv->bundleStats.dropFragments++; 1383 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1384 NG_FREE_M(qent->data); 1385 NG_FREE_META(qent->meta); 1386 FREE(qent, M_NETGRAPH_PPP); 1387 priv->qlen--; 1388 1389 /* Process queue again */ 1390 return ng_ppp_frag_process(node); 1391 } 1392 1393 /* Done */ 1394 return (0); 1395 } 1396 1397 /* 1398 * Check for 'stale' completed packets that need to be delivered 1399 * 1400 * If a link goes down or has a temporary failure, MSEQ can get 1401 * "stuck", because no new incoming fragments appear on that link. 1402 * This can cause completed packets to never get delivered if 1403 * their sequence numbers are all > MSEQ + 1. 1404 * 1405 * This routine checks how long all of the completed packets have 1406 * been sitting in the queue, and if too long, removes fragments 1407 * from the queue and increments MSEQ to allow them to be delivered. 1408 */ 1409 static void 1410 ng_ppp_frag_checkstale(node_p node) 1411 { 1412 const priv_p priv = NG_NODE_PRIVATE(node); 1413 struct ng_ppp_frag *qent, *beg, *end; 1414 struct timeval now, age; 1415 struct mbuf *m; 1416 meta_p meta; 1417 int i, seq; 1418 item_p item; 1419 1420 now.tv_sec = 0; /* uninitialized state */ 1421 while (1) { 1422 1423 /* If queue is empty, we're done */ 1424 if (TAILQ_EMPTY(&priv->frags)) 1425 break; 1426 1427 /* Find the first complete packet in the queue */ 1428 beg = end = NULL; 1429 seq = TAILQ_FIRST(&priv->frags)->seq; 1430 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1431 if (qent->first) 1432 beg = qent; 1433 else if (qent->seq != seq) 1434 beg = NULL; 1435 if (beg != NULL && qent->last) { 1436 end = qent; 1437 break; 1438 } 1439 seq = MP_NEXT_RECV_SEQ(priv, seq); 1440 } 1441 1442 /* If none found, exit */ 1443 if (end == NULL) 1444 break; 1445 1446 /* Get current time (we assume we've been up for >= 1 second) */ 1447 if (now.tv_sec == 0) 1448 getmicrouptime(&now); 1449 1450 /* Check if packet has been queued too long */ 1451 age = now; 1452 timevalsub(&age, &beg->timestamp); 1453 if (timevalcmp(&age, &ng_ppp_max_staleness, < )) 1454 break; 1455 1456 /* Throw away junk fragments in front of the completed packet */ 1457 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) { 1458 KASSERT(!TAILQ_EMPTY(&priv->frags), 1459 ("%s: empty q", __func__)); 1460 priv->bundleStats.dropFragments++; 1461 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1462 NG_FREE_M(qent->data); 1463 NG_FREE_META(qent->meta); 1464 FREE(qent, M_NETGRAPH_PPP); 1465 priv->qlen--; 1466 } 1467 1468 /* Extract completed packet */ 1469 ng_ppp_get_packet(node, &m, &meta); 1470 1471 /* Bump MSEQ if necessary */ 1472 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) { 1473 priv->mseq = end->seq; 1474 for (i = 0; i < priv->numActiveLinks; i++) { 1475 struct ng_ppp_link *const alink = 1476 &priv->links[priv->activeLinks[i]]; 1477 1478 if (MP_RECV_SEQ_DIFF(priv, 1479 alink->seq, priv->mseq) < 0) 1480 alink->seq = priv->mseq; 1481 } 1482 } 1483 1484 /* Deliver packet */ 1485 item = ng_package_data(m, meta); 1486 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1487 } 1488 } 1489 1490 /* 1491 * Periodically call ng_ppp_frag_checkstale() 1492 */ 1493 static void 1494 ng_ppp_frag_timeout(void *arg) 1495 { 1496 const node_p node = arg; 1497 const priv_p priv = NG_NODE_PRIVATE(node); 1498 int s = splnet(); 1499 1500 /* Handle the race where shutdown happens just before splnet() above */ 1501 if (NG_NODE_NOT_VALID(node)) { 1502 NG_NODE_UNREF(node); 1503 splx(s); 1504 return; 1505 } 1506 1507 /* Reset timer state after timeout */ 1508 KASSERT(priv->timerActive, ("%s: !timerActive", __func__)); 1509 priv->timerActive = 0; 1510 KASSERT(node->nd_refs > 1, ("%s: nd_refs=%d", __func__, node->nd_refs)); 1511 NG_NODE_UNREF(node); 1512 1513 /* Start timer again */ 1514 ng_ppp_start_frag_timer(node); 1515 1516 /* Scan the fragment queue */ 1517 ng_ppp_frag_checkstale(node); 1518 splx(s); 1519 } 1520 1521 /* 1522 * Deliver a frame out on the bundle, i.e., figure out how to fragment 1523 * the frame across the individual PPP links and do so. 1524 */ 1525 static int 1526 ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta) 1527 { 1528 const priv_p priv = NG_NODE_PRIVATE(node); 1529 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4; 1530 int distrib[NG_PPP_MAX_LINKS]; 1531 int firstFragment; 1532 int activeLinkNum; 1533 item_p item; 1534 1535 /* At least one link must be active */ 1536 if (priv->numActiveLinks == 0) { 1537 NG_FREE_M(m); 1538 NG_FREE_META(meta); 1539 return (ENETDOWN); 1540 } 1541 1542 /* Round-robin strategy */ 1543 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) { 1544 activeLinkNum = priv->lastLink++ % priv->numActiveLinks; 1545 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0])); 1546 distrib[activeLinkNum] = m->m_pkthdr.len; 1547 goto deliver; 1548 } 1549 1550 /* Strategy when all links are equivalent (optimize the common case) */ 1551 if (priv->allLinksEqual) { 1552 const int fraction = m->m_pkthdr.len / priv->numActiveLinks; 1553 int i, remain; 1554 1555 for (i = 0; i < priv->numActiveLinks; i++) 1556 distrib[priv->lastLink++ % priv->numActiveLinks] 1557 = fraction; 1558 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks); 1559 while (remain > 0) { 1560 distrib[priv->lastLink++ % priv->numActiveLinks]++; 1561 remain--; 1562 } 1563 goto deliver; 1564 } 1565 1566 /* Strategy when all links are not equivalent */ 1567 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib); 1568 1569 deliver: 1570 /* Update stats */ 1571 priv->bundleStats.xmitFrames++; 1572 priv->bundleStats.xmitOctets += m->m_pkthdr.len; 1573 1574 /* Send alloted portions of frame out on the link(s) */ 1575 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1; 1576 activeLinkNum >= 0; activeLinkNum--) { 1577 const int linkNum = priv->activeLinks[activeLinkNum]; 1578 struct ng_ppp_link *const link = &priv->links[linkNum]; 1579 1580 /* Deliver fragment(s) out the next link */ 1581 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) { 1582 int len, lastFragment, error; 1583 struct mbuf *m2; 1584 meta_p meta2; 1585 1586 /* Calculate fragment length; don't exceed link MTU */ 1587 len = distrib[activeLinkNum]; 1588 if (len > link->conf.mru - hdr_len) 1589 len = link->conf.mru - hdr_len; 1590 distrib[activeLinkNum] -= len; 1591 lastFragment = (len == m->m_pkthdr.len); 1592 1593 /* Split off next fragment as "m2" */ 1594 m2 = m; 1595 if (!lastFragment) { 1596 struct mbuf *n = m_split(m, len, M_NOWAIT); 1597 1598 if (n == NULL) { 1599 NG_FREE_M(m); 1600 NG_FREE_META(meta); 1601 return (ENOMEM); 1602 } 1603 m = n; 1604 } 1605 1606 /* Prepend MP header */ 1607 if (priv->conf.xmitShortSeq) { 1608 u_int16_t shdr; 1609 1610 shdr = priv->xseq; 1611 priv->xseq = 1612 (priv->xseq + 1) & MP_SHORT_SEQ_MASK; 1613 if (firstFragment) 1614 shdr |= MP_SHORT_FIRST_FLAG; 1615 if (lastFragment) 1616 shdr |= MP_SHORT_LAST_FLAG; 1617 shdr = htons(shdr); 1618 m2 = ng_ppp_prepend(m2, &shdr, 2); 1619 } else { 1620 u_int32_t lhdr; 1621 1622 lhdr = priv->xseq; 1623 priv->xseq = 1624 (priv->xseq + 1) & MP_LONG_SEQ_MASK; 1625 if (firstFragment) 1626 lhdr |= MP_LONG_FIRST_FLAG; 1627 if (lastFragment) 1628 lhdr |= MP_LONG_LAST_FLAG; 1629 lhdr = htonl(lhdr); 1630 m2 = ng_ppp_prepend(m2, &lhdr, 4); 1631 } 1632 if (m2 == NULL) { 1633 if (!lastFragment) 1634 m_freem(m); 1635 NG_FREE_META(meta); 1636 return (ENOBUFS); 1637 } 1638 1639 /* Copy the meta information, if any */ 1640 meta2 = lastFragment ? meta : ng_copy_meta(meta); 1641 1642 /* Send fragment */ 1643 item = ng_package_data(m2, meta2); 1644 error = ng_ppp_output(node, 0, PROT_MP, linkNum, item); 1645 if (error != 0) { 1646 if (!lastFragment) { 1647 NG_FREE_M(m); 1648 NG_FREE_META(meta); 1649 } 1650 return (error); 1651 } 1652 } 1653 } 1654 1655 /* Done */ 1656 return (0); 1657 } 1658 1659 /* 1660 * Computing the optimal fragmentation 1661 * ----------------------------------- 1662 * 1663 * This routine tries to compute the optimal fragmentation pattern based 1664 * on each link's latency, bandwidth, and calculated additional latency. 1665 * The latter quantity is the additional latency caused by previously 1666 * written data that has not been transmitted yet. 1667 * 1668 * This algorithm is only useful when not all of the links have the 1669 * same latency and bandwidth values. 1670 * 1671 * The essential idea is to make the last bit of each fragment of the 1672 * frame arrive at the opposite end at the exact same time. This greedy 1673 * algorithm is optimal, in that no other scheduling could result in any 1674 * packet arriving any sooner unless packets are delivered out of order. 1675 * 1676 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and 1677 * latency l_i (in miliseconds). Consider the function function f_i(t) 1678 * which is equal to the number of bytes that will have arrived at 1679 * the peer after t miliseconds if we start writing continuously at 1680 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i). 1681 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i). 1682 * Note that the y-intersect is always <= zero because latency can't be 1683 * negative. Note also that really the function is f_i(t) except when 1684 * f_i(t) is negative, in which case the function is zero. To take 1685 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }. 1686 * So the actual number of bytes that will have arrived at the peer after 1687 * t miliseconds is f_i(t) * Q_i(t). 1688 * 1689 * At any given time, each link has some additional latency a_i >= 0 1690 * due to previously written fragment(s) which are still in the queue. 1691 * This value is easily computed from the time since last transmission, 1692 * the previous latency value, the number of bytes written, and the 1693 * link's bandwidth. 1694 * 1695 * Assume that l_i includes any a_i already, and that the links are 1696 * sorted by latency, so that l_i <= l_{i+1}. 1697 * 1698 * Let N be the total number of bytes in the current frame we are sending. 1699 * 1700 * Suppose we were to start writing bytes at time t = 0 on all links 1701 * simultaneously, which is the most we can possibly do. Then let 1702 * F(t) be equal to the total number of bytes received by the peer 1703 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)). 1704 * 1705 * Our goal is simply this: fragment the frame across the links such 1706 * that the peer is able to reconstruct the completed frame as soon as 1707 * possible, i.e., at the least possible value of t. Call this value t_0. 1708 * 1709 * Then it follows that F(t_0) = N. Our strategy is first to find the value 1710 * of t_0, and then deduce how many bytes to write to each link. 1711 * 1712 * Rewriting F(t_0): 1713 * 1714 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) ) 1715 * 1716 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will 1717 * lie in one of these ranges. To find it, we just need to find the i such 1718 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values 1719 * for Q_i() in this range, plug in the remaining values, solving for t_0. 1720 * 1721 * Once t_0 is known, then the number of bytes to send on link i is 1722 * just f_i(t_0) * Q_i(t_0). 1723 * 1724 * In other words, we start allocating bytes to the links one at a time. 1725 * We keep adding links until the frame is completely sent. Some links 1726 * may not get any bytes because their latency is too high. 1727 * 1728 * Is all this work really worth the trouble? Depends on the situation. 1729 * The bigger the ratio of computer speed to link speed, and the more 1730 * important total bundle latency is (e.g., for interactive response time), 1731 * the more it's worth it. There is however the cost of calling this 1732 * function for every frame. The running time is O(n^2) where n is the 1733 * number of links that receive a non-zero number of bytes. 1734 * 1735 * Since latency is measured in miliseconds, the "resolution" of this 1736 * algorithm is one milisecond. 1737 * 1738 * To avoid this algorithm altogether, configure all links to have the 1739 * same latency and bandwidth. 1740 */ 1741 static void 1742 ng_ppp_mp_strategy(node_p node, int len, int *distrib) 1743 { 1744 const priv_p priv = NG_NODE_PRIVATE(node); 1745 int latency[NG_PPP_MAX_LINKS]; 1746 int sortByLatency[NG_PPP_MAX_LINKS]; 1747 int activeLinkNum; 1748 int t0, total, topSum, botSum; 1749 struct timeval now; 1750 int i, numFragments; 1751 1752 /* If only one link, this gets real easy */ 1753 if (priv->numActiveLinks == 1) { 1754 distrib[0] = len; 1755 return; 1756 } 1757 1758 /* Get current time */ 1759 getmicrouptime(&now); 1760 1761 /* Compute latencies for each link at this point in time */ 1762 for (activeLinkNum = 0; 1763 activeLinkNum < priv->numActiveLinks; activeLinkNum++) { 1764 struct ng_ppp_link *alink; 1765 struct timeval diff; 1766 int xmitBytes; 1767 1768 /* Start with base latency value */ 1769 alink = &priv->links[priv->activeLinks[activeLinkNum]]; 1770 latency[activeLinkNum] = alink->conf.latency; 1771 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */ 1772 1773 /* Any additional latency? */ 1774 if (alink->bytesInQueue == 0) 1775 continue; 1776 1777 /* Compute time delta since last write */ 1778 diff = now; 1779 timevalsub(&diff, &alink->lastWrite); 1780 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */ 1781 alink->bytesInQueue = 0; 1782 continue; 1783 } 1784 1785 /* How many bytes could have transmitted since last write? */ 1786 xmitBytes = (alink->conf.bandwidth * diff.tv_sec) 1787 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100; 1788 alink->bytesInQueue -= xmitBytes; 1789 if (alink->bytesInQueue < 0) 1790 alink->bytesInQueue = 0; 1791 else 1792 latency[activeLinkNum] += 1793 (100 * alink->bytesInQueue) / alink->conf.bandwidth; 1794 } 1795 1796 /* Sort active links by latency */ 1797 compareLatencies = latency; 1798 qsort(sortByLatency, 1799 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp); 1800 compareLatencies = NULL; 1801 1802 /* Find the interval we need (add links in sortByLatency[] order) */ 1803 for (numFragments = 1; 1804 numFragments < priv->numActiveLinks; numFragments++) { 1805 for (total = i = 0; i < numFragments; i++) { 1806 int flowTime; 1807 1808 flowTime = latency[sortByLatency[numFragments]] 1809 - latency[sortByLatency[i]]; 1810 total += ((flowTime * priv->links[ 1811 priv->activeLinks[sortByLatency[i]]].conf.bandwidth) 1812 + 99) / 100; 1813 } 1814 if (total >= len) 1815 break; 1816 } 1817 1818 /* Solve for t_0 in that interval */ 1819 for (topSum = botSum = i = 0; i < numFragments; i++) { 1820 int bw = priv->links[ 1821 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1822 1823 topSum += latency[sortByLatency[i]] * bw; /* / 100 */ 1824 botSum += bw; /* / 100 */ 1825 } 1826 t0 = ((len * 100) + topSum + botSum / 2) / botSum; 1827 1828 /* Compute f_i(t_0) all i */ 1829 bzero(distrib, priv->numActiveLinks * sizeof(*distrib)); 1830 for (total = i = 0; i < numFragments; i++) { 1831 int bw = priv->links[ 1832 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1833 1834 distrib[sortByLatency[i]] = 1835 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100; 1836 total += distrib[sortByLatency[i]]; 1837 } 1838 1839 /* Deal with any rounding error */ 1840 if (total < len) { 1841 struct ng_ppp_link *fastLink = 1842 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1843 int fast = 0; 1844 1845 /* Find the fastest link */ 1846 for (i = 1; i < numFragments; i++) { 1847 struct ng_ppp_link *const link = 1848 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1849 1850 if (link->conf.bandwidth > fastLink->conf.bandwidth) { 1851 fast = i; 1852 fastLink = link; 1853 } 1854 } 1855 distrib[sortByLatency[fast]] += len - total; 1856 } else while (total > len) { 1857 struct ng_ppp_link *slowLink = 1858 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1859 int delta, slow = 0; 1860 1861 /* Find the slowest link that still has bytes to remove */ 1862 for (i = 1; i < numFragments; i++) { 1863 struct ng_ppp_link *const link = 1864 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1865 1866 if (distrib[sortByLatency[slow]] == 0 1867 || (distrib[sortByLatency[i]] > 0 1868 && link->conf.bandwidth < 1869 slowLink->conf.bandwidth)) { 1870 slow = i; 1871 slowLink = link; 1872 } 1873 } 1874 delta = total - len; 1875 if (delta > distrib[sortByLatency[slow]]) 1876 delta = distrib[sortByLatency[slow]]; 1877 distrib[sortByLatency[slow]] -= delta; 1878 total -= delta; 1879 } 1880 } 1881 1882 /* 1883 * Compare two integers 1884 */ 1885 static int 1886 ng_ppp_intcmp(const void *v1, const void *v2) 1887 { 1888 const int index1 = *((const int *) v1); 1889 const int index2 = *((const int *) v2); 1890 1891 return compareLatencies[index1] - compareLatencies[index2]; 1892 } 1893 1894 /* 1895 * Prepend a possibly compressed PPP protocol number in front of a frame 1896 */ 1897 static struct mbuf * 1898 ng_ppp_addproto(struct mbuf *m, int proto, int compOK) 1899 { 1900 if (compOK && PROT_COMPRESSABLE(proto)) { 1901 u_char pbyte = (u_char)proto; 1902 1903 return ng_ppp_prepend(m, &pbyte, 1); 1904 } else { 1905 u_int16_t pword = htons((u_int16_t)proto); 1906 1907 return ng_ppp_prepend(m, &pword, 2); 1908 } 1909 } 1910 1911 /* 1912 * Prepend some bytes to an mbuf 1913 */ 1914 static struct mbuf * 1915 ng_ppp_prepend(struct mbuf *m, const void *buf, int len) 1916 { 1917 M_PREPEND(m, len, M_NOWAIT); 1918 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL)) 1919 return (NULL); 1920 bcopy(buf, mtod(m, u_char *), len); 1921 return (m); 1922 } 1923 1924 /* 1925 * Update private information that is derived from other private information 1926 */ 1927 static void 1928 ng_ppp_update(node_p node, int newConf) 1929 { 1930 const priv_p priv = NG_NODE_PRIVATE(node); 1931 int i; 1932 1933 /* Update active status for VJ Compression */ 1934 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL 1935 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL 1936 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL 1937 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL; 1938 1939 /* Increase latency for each link an amount equal to one MP header */ 1940 if (newConf) { 1941 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1942 int hdrBytes; 1943 1944 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2) 1945 + (priv->links[i].conf.enableProtoComp ? 1 : 2) 1946 + (priv->conf.xmitShortSeq ? 2 : 4); 1947 priv->links[i].conf.latency += 1948 ((hdrBytes * priv->links[i].conf.bandwidth) + 50) 1949 / 100; 1950 } 1951 } 1952 1953 /* Update list of active links */ 1954 bzero(&priv->activeLinks, sizeof(priv->activeLinks)); 1955 priv->numActiveLinks = 0; 1956 priv->allLinksEqual = 1; 1957 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1958 struct ng_ppp_link *const link = &priv->links[i]; 1959 1960 /* Is link active? */ 1961 if (link->conf.enableLink && link->hook != NULL) { 1962 struct ng_ppp_link *link0; 1963 1964 /* Add link to list of active links */ 1965 priv->activeLinks[priv->numActiveLinks++] = i; 1966 link0 = &priv->links[priv->activeLinks[0]]; 1967 1968 /* Determine if all links are still equal */ 1969 if (link->conf.latency != link0->conf.latency 1970 || link->conf.bandwidth != link0->conf.bandwidth) 1971 priv->allLinksEqual = 0; 1972 1973 /* Initialize rec'd sequence number */ 1974 if (link->seq == MP_NOSEQ) { 1975 link->seq = (link == link0) ? 1976 MP_INITIAL_SEQ : link0->seq; 1977 } 1978 } else 1979 link->seq = MP_NOSEQ; 1980 } 1981 1982 /* Update MP state as multi-link is active or not */ 1983 if (priv->conf.enableMultilink && priv->numActiveLinks > 0) 1984 ng_ppp_start_frag_timer(node); 1985 else { 1986 ng_ppp_stop_frag_timer(node); 1987 ng_ppp_frag_reset(node); 1988 priv->xseq = MP_INITIAL_SEQ; 1989 priv->mseq = MP_INITIAL_SEQ; 1990 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1991 struct ng_ppp_link *const link = &priv->links[i]; 1992 1993 bzero(&link->lastWrite, sizeof(link->lastWrite)); 1994 link->bytesInQueue = 0; 1995 link->seq = MP_NOSEQ; 1996 } 1997 } 1998 } 1999 2000 /* 2001 * Determine if a new configuration would represent a valid change 2002 * from the current configuration and link activity status. 2003 */ 2004 static int 2005 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf) 2006 { 2007 const priv_p priv = NG_NODE_PRIVATE(node); 2008 int i, newNumLinksActive; 2009 2010 /* Check per-link config and count how many links would be active */ 2011 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) { 2012 if (newConf->links[i].enableLink && priv->links[i].hook != NULL) 2013 newNumLinksActive++; 2014 if (!newConf->links[i].enableLink) 2015 continue; 2016 if (newConf->links[i].mru < MP_MIN_LINK_MRU) 2017 return (0); 2018 if (newConf->links[i].bandwidth == 0) 2019 return (0); 2020 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH) 2021 return (0); 2022 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY) 2023 return (0); 2024 } 2025 2026 /* Check bundle parameters */ 2027 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU) 2028 return (0); 2029 2030 /* Disallow changes to multi-link configuration while MP is active */ 2031 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) { 2032 if (!priv->conf.enableMultilink 2033 != !newConf->bund.enableMultilink 2034 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq 2035 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq) 2036 return (0); 2037 } 2038 2039 /* At most one link can be active unless multi-link is enabled */ 2040 if (!newConf->bund.enableMultilink && newNumLinksActive > 1) 2041 return (0); 2042 2043 /* Configuration change would be valid */ 2044 return (1); 2045 } 2046 2047 /* 2048 * Free all entries in the fragment queue 2049 */ 2050 static void 2051 ng_ppp_frag_reset(node_p node) 2052 { 2053 const priv_p priv = NG_NODE_PRIVATE(node); 2054 struct ng_ppp_frag *qent, *qnext; 2055 2056 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) { 2057 qnext = TAILQ_NEXT(qent, f_qent); 2058 NG_FREE_M(qent->data); 2059 NG_FREE_META(qent->meta); 2060 FREE(qent, M_NETGRAPH_PPP); 2061 } 2062 TAILQ_INIT(&priv->frags); 2063 priv->qlen = 0; 2064 } 2065 2066 /* 2067 * Start fragment queue timer 2068 */ 2069 static void 2070 ng_ppp_start_frag_timer(node_p node) 2071 { 2072 const priv_p priv = NG_NODE_PRIVATE(node); 2073 2074 if (!priv->timerActive) { 2075 priv->fragTimer = timeout(ng_ppp_frag_timeout, 2076 node, MP_FRAGTIMER_INTERVAL); 2077 priv->timerActive = 1; 2078 NG_NODE_REF(node); 2079 } 2080 } 2081 2082 /* 2083 * Stop fragment queue timer 2084 */ 2085 static void 2086 ng_ppp_stop_frag_timer(node_p node) 2087 { 2088 const priv_p priv = NG_NODE_PRIVATE(node); 2089 2090 if (priv->timerActive) { 2091 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer); 2092 priv->timerActive = 0; 2093 KASSERT(node->nd_refs > 1, 2094 ("%s: nd_refs=%d", __func__, node->nd_refs)); 2095 NG_NODE_UNREF(node); 2096 } 2097 } 2098 2099