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/limits.h> 51 #include <sys/time.h> 52 #include <sys/mbuf.h> 53 #include <sys/malloc.h> 54 #include <sys/errno.h> 55 #include <sys/ctype.h> 56 57 #include <netgraph/ng_message.h> 58 #include <netgraph/netgraph.h> 59 #include <netgraph/ng_parse.h> 60 #include <netgraph/ng_ppp.h> 61 #include <netgraph/ng_vjc.h> 62 63 #ifdef NG_SEPARATE_MALLOC 64 MALLOC_DEFINE(M_NETGRAPH_PPP, "netgraph_ppp", "netgraph ppp node"); 65 #else 66 #define M_NETGRAPH_PPP M_NETGRAPH 67 #endif 68 69 #define PROT_VALID(p) (((p) & 0x0101) == 0x0001) 70 #define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000) 71 72 /* Some PPP protocol numbers we're interested in */ 73 #define PROT_APPLETALK 0x0029 74 #define PROT_COMPD 0x00fd 75 #define PROT_CRYPTD 0x0053 76 #define PROT_IP 0x0021 77 #define PROT_IPV6 0x0057 78 #define PROT_IPX 0x002b 79 #define PROT_LCP 0xc021 80 #define PROT_MP 0x003d 81 #define PROT_VJCOMP 0x002d 82 #define PROT_VJUNCOMP 0x002f 83 84 /* Multilink PPP definitions */ 85 #define MP_MIN_MRRU 1500 /* per RFC 1990 */ 86 #define MP_INITIAL_SEQ 0 /* per RFC 1990 */ 87 #define MP_MIN_LINK_MRU 32 88 89 #define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */ 90 #define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */ 91 #define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */ 92 #define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */ 93 94 #define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */ 95 #define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */ 96 #define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */ 97 #define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */ 98 99 #define MP_NOSEQ 0x7fffffff /* impossible sequence number */ 100 101 /* Sign extension of MP sequence numbers */ 102 #define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \ 103 ((s) | ~MP_SHORT_SEQ_MASK) \ 104 : ((s) & MP_SHORT_SEQ_MASK)) 105 #define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \ 106 ((s) | ~MP_LONG_SEQ_MASK) \ 107 : ((s) & MP_LONG_SEQ_MASK)) 108 109 /* Comparision of MP sequence numbers. Note: all sequence numbers 110 except priv->xseq are stored with the sign bit extended. */ 111 #define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y)) 112 #define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y)) 113 114 #define MP_RECV_SEQ_DIFF(priv,x,y) \ 115 ((priv)->conf.recvShortSeq ? \ 116 MP_SHORT_SEQ_DIFF((x), (y)) : \ 117 MP_LONG_SEQ_DIFF((x), (y))) 118 119 /* Increment receive sequence number */ 120 #define MP_NEXT_RECV_SEQ(priv,seq) \ 121 ((priv)->conf.recvShortSeq ? \ 122 MP_SHORT_EXTEND((seq) + 1) : \ 123 MP_LONG_EXTEND((seq) + 1)) 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 */ 135 struct 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 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */ 142 }; 143 144 /* We use integer indicies to refer to the non-link hooks */ 145 static const char *const ng_ppp_hook_names[] = { 146 NG_PPP_HOOK_ATALK, 147 #define HOOK_INDEX_ATALK 0 148 NG_PPP_HOOK_BYPASS, 149 #define HOOK_INDEX_BYPASS 1 150 NG_PPP_HOOK_COMPRESS, 151 #define HOOK_INDEX_COMPRESS 2 152 NG_PPP_HOOK_ENCRYPT, 153 #define HOOK_INDEX_ENCRYPT 3 154 NG_PPP_HOOK_DECOMPRESS, 155 #define HOOK_INDEX_DECOMPRESS 4 156 NG_PPP_HOOK_DECRYPT, 157 #define HOOK_INDEX_DECRYPT 5 158 NG_PPP_HOOK_INET, 159 #define HOOK_INDEX_INET 6 160 NG_PPP_HOOK_IPX, 161 #define HOOK_INDEX_IPX 7 162 NG_PPP_HOOK_VJC_COMP, 163 #define HOOK_INDEX_VJC_COMP 8 164 NG_PPP_HOOK_VJC_IP, 165 #define HOOK_INDEX_VJC_IP 9 166 NG_PPP_HOOK_VJC_UNCOMP, 167 #define HOOK_INDEX_VJC_UNCOMP 10 168 NG_PPP_HOOK_VJC_VJIP, 169 #define HOOK_INDEX_VJC_VJIP 11 170 NG_PPP_HOOK_IPV6, 171 #define HOOK_INDEX_IPV6 12 172 NULL 173 #define HOOK_INDEX_MAX 13 174 }; 175 176 /* We store index numbers in the hook private pointer. The HOOK_INDEX() 177 for a hook is either the index (above) for normal hooks, or the ones 178 complement of the link number for link hooks. 179 XXX Not any more.. (what a hack) 180 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private)) 181 */ 182 183 /* Per-link private information */ 184 struct ng_ppp_link { 185 struct ng_ppp_link_conf conf; /* link configuration */ 186 hook_p hook; /* connection to link data */ 187 int32_t seq; /* highest rec'd seq# - MSEQ */ 188 struct timeval lastWrite; /* time of last write */ 189 int bytesInQueue; /* bytes in the output queue */ 190 struct ng_ppp_link_stat stats; /* Link stats */ 191 }; 192 193 /* Total per-node private information */ 194 struct ng_ppp_private { 195 struct ng_ppp_bund_conf conf; /* bundle config */ 196 struct ng_ppp_link_stat bundleStats; /* bundle stats */ 197 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */ 198 int32_t xseq; /* next out MP seq # */ 199 int32_t mseq; /* min links[i].seq */ 200 u_char vjCompHooked; /* VJ comp hooked up? */ 201 u_char allLinksEqual; /* all xmit the same? */ 202 u_char timerActive; /* frag timer active? */ 203 u_int numActiveLinks; /* how many links up */ 204 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */ 205 u_int lastLink; /* for round robin */ 206 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */ 207 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */ 208 frags; 209 int qlen; /* fraq queue length */ 210 struct callout_handle fragTimer; /* fraq queue check */ 211 }; 212 typedef struct ng_ppp_private *priv_p; 213 214 /* Netgraph node methods */ 215 static ng_constructor_t ng_ppp_constructor; 216 static ng_rcvmsg_t ng_ppp_rcvmsg; 217 static ng_shutdown_t ng_ppp_shutdown; 218 static ng_newhook_t ng_ppp_newhook; 219 static ng_rcvdata_t ng_ppp_rcvdata; 220 static ng_disconnect_t ng_ppp_disconnect; 221 222 /* Helper functions */ 223 static int ng_ppp_input(node_p node, int bypass, 224 int linkNum, item_p item); 225 static int ng_ppp_output(node_p node, int bypass, int proto, 226 int linkNum, item_p item); 227 static int ng_ppp_mp_input(node_p node, int linkNum, item_p item); 228 static int ng_ppp_check_packet(node_p node); 229 static void ng_ppp_get_packet(node_p node, struct mbuf **mp); 230 static int ng_ppp_frag_process(node_p node); 231 static int ng_ppp_frag_trim(node_p node); 232 static void ng_ppp_frag_timeout(void *arg); 233 static void ng_ppp_frag_checkstale(node_p node); 234 static void ng_ppp_frag_reset(node_p node); 235 static int ng_ppp_mp_output(node_p node, struct mbuf *m); 236 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib); 237 static int ng_ppp_intcmp(const void *v1, const void *v2); 238 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK); 239 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len); 240 static int ng_ppp_config_valid(node_p node, 241 const struct ng_ppp_node_conf *newConf); 242 static void ng_ppp_update(node_p node, int newConf); 243 static void ng_ppp_start_frag_timer(node_p node); 244 static void ng_ppp_stop_frag_timer(node_p node); 245 246 /* Parse type for struct ng_ppp_mp_state_type */ 247 static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = { 248 &ng_parse_hint32_type, 249 NG_PPP_MAX_LINKS 250 }; 251 static const struct ng_parse_type ng_ppp_rseq_array_type = { 252 &ng_parse_fixedarray_type, 253 &ng_ppp_rseq_array_info, 254 }; 255 static const struct ng_parse_struct_field ng_ppp_mp_state_type_fields[] 256 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type); 257 static const struct ng_parse_type ng_ppp_mp_state_type = { 258 &ng_parse_struct_type, 259 &ng_ppp_mp_state_type_fields 260 }; 261 262 /* Parse type for struct ng_ppp_link_conf */ 263 static const struct ng_parse_struct_field ng_ppp_link_type_fields[] 264 = NG_PPP_LINK_TYPE_INFO; 265 static const struct ng_parse_type ng_ppp_link_type = { 266 &ng_parse_struct_type, 267 &ng_ppp_link_type_fields 268 }; 269 270 /* Parse type for struct ng_ppp_bund_conf */ 271 static const struct ng_parse_struct_field ng_ppp_bund_type_fields[] 272 = NG_PPP_BUND_TYPE_INFO; 273 static const struct ng_parse_type ng_ppp_bund_type = { 274 &ng_parse_struct_type, 275 &ng_ppp_bund_type_fields 276 }; 277 278 /* Parse type for struct ng_ppp_node_conf */ 279 static const struct ng_parse_fixedarray_info ng_ppp_array_info = { 280 &ng_ppp_link_type, 281 NG_PPP_MAX_LINKS 282 }; 283 static const struct ng_parse_type ng_ppp_link_array_type = { 284 &ng_parse_fixedarray_type, 285 &ng_ppp_array_info, 286 }; 287 static const struct ng_parse_struct_field ng_ppp_conf_type_fields[] 288 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type); 289 static const struct ng_parse_type ng_ppp_conf_type = { 290 &ng_parse_struct_type, 291 &ng_ppp_conf_type_fields 292 }; 293 294 /* Parse type for struct ng_ppp_link_stat */ 295 static const struct ng_parse_struct_field ng_ppp_stats_type_fields[] 296 = NG_PPP_STATS_TYPE_INFO; 297 static const struct ng_parse_type ng_ppp_stats_type = { 298 &ng_parse_struct_type, 299 &ng_ppp_stats_type_fields 300 }; 301 302 /* List of commands and how to convert arguments to/from ASCII */ 303 static const struct ng_cmdlist ng_ppp_cmds[] = { 304 { 305 NGM_PPP_COOKIE, 306 NGM_PPP_SET_CONFIG, 307 "setconfig", 308 &ng_ppp_conf_type, 309 NULL 310 }, 311 { 312 NGM_PPP_COOKIE, 313 NGM_PPP_GET_CONFIG, 314 "getconfig", 315 NULL, 316 &ng_ppp_conf_type 317 }, 318 { 319 NGM_PPP_COOKIE, 320 NGM_PPP_GET_MP_STATE, 321 "getmpstate", 322 NULL, 323 &ng_ppp_mp_state_type 324 }, 325 { 326 NGM_PPP_COOKIE, 327 NGM_PPP_GET_LINK_STATS, 328 "getstats", 329 &ng_parse_int16_type, 330 &ng_ppp_stats_type 331 }, 332 { 333 NGM_PPP_COOKIE, 334 NGM_PPP_CLR_LINK_STATS, 335 "clrstats", 336 &ng_parse_int16_type, 337 NULL 338 }, 339 { 340 NGM_PPP_COOKIE, 341 NGM_PPP_GETCLR_LINK_STATS, 342 "getclrstats", 343 &ng_parse_int16_type, 344 &ng_ppp_stats_type 345 }, 346 { 0 } 347 }; 348 349 /* Node type descriptor */ 350 static struct ng_type ng_ppp_typestruct = { 351 .version = NG_ABI_VERSION, 352 .name = NG_PPP_NODE_TYPE, 353 .constructor = ng_ppp_constructor, 354 .rcvmsg = ng_ppp_rcvmsg, 355 .shutdown = ng_ppp_shutdown, 356 .newhook = ng_ppp_newhook, 357 .rcvdata = ng_ppp_rcvdata, 358 .disconnect = ng_ppp_disconnect, 359 .cmdlist = ng_ppp_cmds, 360 }; 361 NETGRAPH_INIT(ppp, &ng_ppp_typestruct); 362 363 static int *compareLatencies; /* hack for ng_ppp_intcmp() */ 364 365 /* Address and control field header */ 366 static const u_char ng_ppp_acf[2] = { 0xff, 0x03 }; 367 368 /* Maximum time we'll let a complete incoming packet sit in the queue */ 369 static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */ 370 371 #define ERROUT(x) do { error = (x); goto done; } while (0) 372 373 /************************************************************************ 374 NETGRAPH NODE STUFF 375 ************************************************************************/ 376 377 /* 378 * Node type constructor 379 */ 380 static int 381 ng_ppp_constructor(node_p node) 382 { 383 priv_p priv; 384 int i; 385 386 /* Allocate private structure */ 387 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_PPP, M_NOWAIT | M_ZERO); 388 if (priv == NULL) 389 return (ENOMEM); 390 391 NG_NODE_SET_PRIVATE(node, priv); 392 393 /* Initialize state */ 394 TAILQ_INIT(&priv->frags); 395 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 396 priv->links[i].seq = MP_NOSEQ; 397 callout_handle_init(&priv->fragTimer); 398 399 /* Done */ 400 return (0); 401 } 402 403 /* 404 * Give our OK for a hook to be added 405 */ 406 static int 407 ng_ppp_newhook(node_p node, hook_p hook, const char *name) 408 { 409 const priv_p priv = NG_NODE_PRIVATE(node); 410 int linkNum = -1; 411 hook_p *hookPtr = NULL; 412 int hookIndex = -1; 413 414 /* Figure out which hook it is */ 415 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */ 416 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) { 417 const char *cp; 418 char *eptr; 419 420 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX); 421 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 422 return (EINVAL); 423 linkNum = (int)strtoul(cp, &eptr, 10); 424 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS) 425 return (EINVAL); 426 hookPtr = &priv->links[linkNum].hook; 427 hookIndex = ~linkNum; 428 } else { /* must be a non-link hook */ 429 int i; 430 431 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) { 432 if (strcmp(name, ng_ppp_hook_names[i]) == 0) { 433 hookPtr = &priv->hooks[i]; 434 hookIndex = i; 435 break; 436 } 437 } 438 if (ng_ppp_hook_names[i] == NULL) 439 return (EINVAL); /* no such hook */ 440 } 441 442 /* See if hook is already connected */ 443 if (*hookPtr != NULL) 444 return (EISCONN); 445 446 /* Disallow more than one link unless multilink is enabled */ 447 if (linkNum != -1 && priv->links[linkNum].conf.enableLink 448 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1) 449 return (ENODEV); 450 451 /* OK */ 452 *hookPtr = hook; 453 NG_HOOK_SET_PRIVATE(hook, (void *)(intptr_t)hookIndex); 454 ng_ppp_update(node, 0); 455 return (0); 456 } 457 458 /* 459 * Receive a control message 460 */ 461 static int 462 ng_ppp_rcvmsg(node_p node, item_p item, hook_p lasthook) 463 { 464 const priv_p priv = NG_NODE_PRIVATE(node); 465 struct ng_mesg *resp = NULL; 466 int error = 0; 467 struct ng_mesg *msg; 468 469 NGI_GET_MSG(item, msg); 470 switch (msg->header.typecookie) { 471 case NGM_PPP_COOKIE: 472 switch (msg->header.cmd) { 473 case NGM_PPP_SET_CONFIG: 474 { 475 struct ng_ppp_node_conf *const conf = 476 (struct ng_ppp_node_conf *)msg->data; 477 int i; 478 479 /* Check for invalid or illegal config */ 480 if (msg->header.arglen != sizeof(*conf)) 481 ERROUT(EINVAL); 482 if (!ng_ppp_config_valid(node, conf)) 483 ERROUT(EINVAL); 484 485 /* Copy config */ 486 priv->conf = conf->bund; 487 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 488 priv->links[i].conf = conf->links[i]; 489 ng_ppp_update(node, 1); 490 break; 491 } 492 case NGM_PPP_GET_CONFIG: 493 { 494 struct ng_ppp_node_conf *conf; 495 int i; 496 497 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT); 498 if (resp == NULL) 499 ERROUT(ENOMEM); 500 conf = (struct ng_ppp_node_conf *)resp->data; 501 conf->bund = priv->conf; 502 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 503 conf->links[i] = priv->links[i].conf; 504 break; 505 } 506 case NGM_PPP_GET_MP_STATE: 507 { 508 struct ng_ppp_mp_state *info; 509 int i; 510 511 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT); 512 if (resp == NULL) 513 ERROUT(ENOMEM); 514 info = (struct ng_ppp_mp_state *)resp->data; 515 bzero(info, sizeof(*info)); 516 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 517 if (priv->links[i].seq != MP_NOSEQ) 518 info->rseq[i] = priv->links[i].seq; 519 } 520 info->mseq = priv->mseq; 521 info->xseq = priv->xseq; 522 break; 523 } 524 case NGM_PPP_GET_LINK_STATS: 525 case NGM_PPP_CLR_LINK_STATS: 526 case NGM_PPP_GETCLR_LINK_STATS: 527 { 528 struct ng_ppp_link_stat *stats; 529 u_int16_t linkNum; 530 531 if (msg->header.arglen != sizeof(u_int16_t)) 532 ERROUT(EINVAL); 533 linkNum = *((u_int16_t *) msg->data); 534 if (linkNum >= NG_PPP_MAX_LINKS 535 && linkNum != NG_PPP_BUNDLE_LINKNUM) 536 ERROUT(EINVAL); 537 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ? 538 &priv->bundleStats : &priv->links[linkNum].stats; 539 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) { 540 NG_MKRESPONSE(resp, msg, 541 sizeof(struct ng_ppp_link_stat), M_NOWAIT); 542 if (resp == NULL) 543 ERROUT(ENOMEM); 544 bcopy(stats, resp->data, sizeof(*stats)); 545 } 546 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS) 547 bzero(stats, sizeof(*stats)); 548 break; 549 } 550 default: 551 error = EINVAL; 552 break; 553 } 554 break; 555 case NGM_VJC_COOKIE: 556 { 557 /* 558 * Forward it to the vjc node. leave the 559 * old return address alone. 560 * If we have no hook, let NG_RESPOND_MSG 561 * clean up any remaining resources. 562 * Because we have no resp, the item will be freed 563 * along with anything it references. Don't 564 * let msg be freed twice. 565 */ 566 NGI_MSG(item) = msg; /* put it back in the item */ 567 msg = NULL; 568 if ((lasthook = priv->links[HOOK_INDEX_VJC_IP].hook)) { 569 NG_FWD_ITEM_HOOK(error, item, lasthook); 570 } 571 return (error); 572 } 573 default: 574 error = EINVAL; 575 break; 576 } 577 done: 578 NG_RESPOND_MSG(error, node, item, resp); 579 NG_FREE_MSG(msg); 580 return (error); 581 } 582 583 /* 584 * Receive data on a hook 585 */ 586 static int 587 ng_ppp_rcvdata(hook_p hook, item_p item) 588 { 589 const node_p node = NG_HOOK_NODE(hook); 590 const priv_p priv = NG_NODE_PRIVATE(node); 591 const int index = (intptr_t)NG_HOOK_PRIVATE(hook); 592 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM; 593 hook_p outHook = NULL; 594 int proto = 0, error; 595 struct mbuf *m; 596 597 NGI_GET_M(item, m); 598 /* Did it come from a link hook? */ 599 if (index < 0) { 600 struct ng_ppp_link *link; 601 602 /* Convert index into a link number */ 603 linkNum = (u_int16_t)~index; 604 KASSERT(linkNum < NG_PPP_MAX_LINKS, 605 ("%s: bogus index 0x%x", __func__, index)); 606 link = &priv->links[linkNum]; 607 608 /* Stats */ 609 link->stats.recvFrames++; 610 link->stats.recvOctets += m->m_pkthdr.len; 611 612 /* Strip address and control fields, if present */ 613 if (m->m_pkthdr.len >= 2) { 614 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 615 NG_FREE_ITEM(item); 616 return (ENOBUFS); 617 } 618 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0) 619 m_adj(m, 2); 620 } 621 622 /* Dispatch incoming frame (if not enabled, to bypass) */ 623 NGI_M(item) = m; /* put changed m back in item */ 624 return ng_ppp_input(node, 625 !link->conf.enableLink, linkNum, item); 626 } 627 628 /* Get protocol & check if data allowed from this hook */ 629 NGI_M(item) = m; /* put possibly changed m back in item */ 630 switch (index) { 631 632 /* Outgoing data */ 633 case HOOK_INDEX_ATALK: 634 if (!priv->conf.enableAtalk) { 635 NG_FREE_ITEM(item); 636 return (ENXIO); 637 } 638 proto = PROT_APPLETALK; 639 break; 640 case HOOK_INDEX_IPX: 641 if (!priv->conf.enableIPX) { 642 NG_FREE_ITEM(item); 643 return (ENXIO); 644 } 645 proto = PROT_IPX; 646 break; 647 case HOOK_INDEX_IPV6: 648 if (!priv->conf.enableIPv6) { 649 NG_FREE_ITEM(item); 650 return (ENXIO); 651 } 652 proto = PROT_IPV6; 653 break; 654 case HOOK_INDEX_INET: 655 case HOOK_INDEX_VJC_VJIP: 656 if (!priv->conf.enableIP) { 657 NG_FREE_ITEM(item); 658 return (ENXIO); 659 } 660 proto = PROT_IP; 661 break; 662 case HOOK_INDEX_VJC_COMP: 663 if (!priv->conf.enableVJCompression) { 664 NG_FREE_ITEM(item); 665 return (ENXIO); 666 } 667 proto = PROT_VJCOMP; 668 break; 669 case HOOK_INDEX_VJC_UNCOMP: 670 if (!priv->conf.enableVJCompression) { 671 NG_FREE_ITEM(item); 672 return (ENXIO); 673 } 674 proto = PROT_VJUNCOMP; 675 break; 676 case HOOK_INDEX_COMPRESS: 677 if (!priv->conf.enableCompression) { 678 NG_FREE_ITEM(item); 679 return (ENXIO); 680 } 681 proto = PROT_COMPD; 682 break; 683 case HOOK_INDEX_ENCRYPT: 684 if (!priv->conf.enableEncryption) { 685 NG_FREE_ITEM(item); 686 return (ENXIO); 687 } 688 proto = PROT_CRYPTD; 689 break; 690 case HOOK_INDEX_BYPASS: 691 if (m->m_pkthdr.len < 4) { 692 NG_FREE_ITEM(item); 693 return (EINVAL); 694 } 695 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 696 NGI_M(item) = NULL; /* don't free twice */ 697 NG_FREE_ITEM(item); 698 return (ENOBUFS); 699 } 700 NGI_M(item) = m; /* m may have changed */ 701 linkNum = ntohs(mtod(m, u_int16_t *)[0]); 702 proto = ntohs(mtod(m, u_int16_t *)[1]); 703 m_adj(m, 4); 704 if (linkNum >= NG_PPP_MAX_LINKS 705 && linkNum != NG_PPP_BUNDLE_LINKNUM) { 706 NG_FREE_ITEM(item); 707 return (EINVAL); 708 } 709 break; 710 711 /* Incoming data */ 712 case HOOK_INDEX_VJC_IP: 713 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) { 714 NG_FREE_ITEM(item); 715 return (ENXIO); 716 } 717 break; 718 case HOOK_INDEX_DECOMPRESS: 719 if (!priv->conf.enableDecompression) { 720 NG_FREE_ITEM(item); 721 return (ENXIO); 722 } 723 break; 724 case HOOK_INDEX_DECRYPT: 725 if (!priv->conf.enableDecryption) { 726 NG_FREE_ITEM(item); 727 return (ENXIO); 728 } 729 break; 730 default: 731 panic("%s: bogus index 0x%x", __func__, index); 732 } 733 734 /* Now figure out what to do with the frame */ 735 switch (index) { 736 737 /* Outgoing data */ 738 case HOOK_INDEX_INET: 739 if (priv->conf.enableVJCompression && priv->vjCompHooked) { 740 outHook = priv->hooks[HOOK_INDEX_VJC_IP]; 741 break; 742 } 743 /* FALLTHROUGH */ 744 case HOOK_INDEX_ATALK: 745 case HOOK_INDEX_IPV6: 746 case HOOK_INDEX_IPX: 747 case HOOK_INDEX_VJC_COMP: 748 case HOOK_INDEX_VJC_UNCOMP: 749 case HOOK_INDEX_VJC_VJIP: 750 if (priv->conf.enableCompression 751 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) { 752 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 753 NGI_M(item) = NULL; 754 NG_FREE_ITEM(item); 755 return (ENOBUFS); 756 } 757 NGI_M(item) = m; /* m may have changed */ 758 outHook = priv->hooks[HOOK_INDEX_COMPRESS]; 759 break; 760 } 761 /* FALLTHROUGH */ 762 case HOOK_INDEX_COMPRESS: 763 if (priv->conf.enableEncryption 764 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) { 765 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 766 NGI_M(item) = NULL; 767 NG_FREE_ITEM(item); 768 return (ENOBUFS); 769 } 770 NGI_M(item) = m; /* m may have changed */ 771 outHook = priv->hooks[HOOK_INDEX_ENCRYPT]; 772 break; 773 } 774 /* FALLTHROUGH */ 775 case HOOK_INDEX_ENCRYPT: 776 return ng_ppp_output(node, 0, proto, NG_PPP_BUNDLE_LINKNUM, item); 777 778 case HOOK_INDEX_BYPASS: 779 return ng_ppp_output(node, 1, proto, linkNum, item); 780 781 /* Incoming data */ 782 case HOOK_INDEX_DECRYPT: 783 case HOOK_INDEX_DECOMPRESS: 784 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 785 786 case HOOK_INDEX_VJC_IP: 787 outHook = priv->hooks[HOOK_INDEX_INET]; 788 break; 789 } 790 791 /* Send packet out hook */ 792 NG_FWD_ITEM_HOOK(error, item, outHook); 793 return (error); 794 } 795 796 /* 797 * Destroy node 798 */ 799 static int 800 ng_ppp_shutdown(node_p node) 801 { 802 const priv_p priv = NG_NODE_PRIVATE(node); 803 804 /* Stop fragment queue timer */ 805 ng_ppp_stop_frag_timer(node); 806 807 /* Take down netgraph node */ 808 ng_ppp_frag_reset(node); 809 bzero(priv, sizeof(*priv)); 810 FREE(priv, M_NETGRAPH_PPP); 811 NG_NODE_SET_PRIVATE(node, NULL); 812 NG_NODE_UNREF(node); /* let the node escape */ 813 return (0); 814 } 815 816 /* 817 * Hook disconnection 818 */ 819 static int 820 ng_ppp_disconnect(hook_p hook) 821 { 822 const node_p node = NG_HOOK_NODE(hook); 823 const priv_p priv = NG_NODE_PRIVATE(node); 824 const int index = (intptr_t)NG_HOOK_PRIVATE(hook); 825 826 /* Zero out hook pointer */ 827 if (index < 0) 828 priv->links[~index].hook = NULL; 829 else 830 priv->hooks[index] = NULL; 831 832 /* Update derived info (or go away if no hooks left) */ 833 if (NG_NODE_NUMHOOKS(node) > 0) { 834 ng_ppp_update(node, 0); 835 } else { 836 if (NG_NODE_IS_VALID(node)) { 837 ng_rmnode_self(node); 838 } 839 } 840 return (0); 841 } 842 843 /************************************************************************ 844 HELPER STUFF 845 ************************************************************************/ 846 847 /* 848 * Handle an incoming frame. Extract the PPP protocol number 849 * and dispatch accordingly. 850 */ 851 static int 852 ng_ppp_input(node_p node, int bypass, int linkNum, item_p item) 853 { 854 const priv_p priv = NG_NODE_PRIVATE(node); 855 hook_p outHook = NULL; 856 int proto, error; 857 struct mbuf *m; 858 859 860 NGI_GET_M(item, m); 861 /* Extract protocol number */ 862 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) { 863 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) { 864 NG_FREE_ITEM(item); 865 return (ENOBUFS); 866 } 867 proto = (proto << 8) + *mtod(m, u_char *); 868 m_adj(m, 1); 869 } 870 if (!PROT_VALID(proto)) { 871 if (linkNum == NG_PPP_BUNDLE_LINKNUM) 872 priv->bundleStats.badProtos++; 873 else 874 priv->links[linkNum].stats.badProtos++; 875 NG_FREE_ITEM(item); 876 NG_FREE_M(m); 877 return (EINVAL); 878 } 879 880 /* Bypass frame? */ 881 if (bypass) 882 goto bypass; 883 884 /* Check protocol */ 885 switch (proto) { 886 case PROT_COMPD: 887 if (priv->conf.enableDecompression) 888 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS]; 889 break; 890 case PROT_CRYPTD: 891 if (priv->conf.enableDecryption) 892 outHook = priv->hooks[HOOK_INDEX_DECRYPT]; 893 break; 894 case PROT_VJCOMP: 895 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 896 outHook = priv->hooks[HOOK_INDEX_VJC_COMP]; 897 break; 898 case PROT_VJUNCOMP: 899 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 900 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP]; 901 break; 902 case PROT_MP: 903 if (priv->conf.enableMultilink 904 && linkNum != NG_PPP_BUNDLE_LINKNUM) { 905 NGI_M(item) = m; 906 return ng_ppp_mp_input(node, linkNum, item); 907 } 908 break; 909 case PROT_APPLETALK: 910 if (priv->conf.enableAtalk) 911 outHook = priv->hooks[HOOK_INDEX_ATALK]; 912 break; 913 case PROT_IPX: 914 if (priv->conf.enableIPX) 915 outHook = priv->hooks[HOOK_INDEX_IPX]; 916 break; 917 case PROT_IP: 918 if (priv->conf.enableIP) 919 outHook = priv->hooks[HOOK_INDEX_INET]; 920 break; 921 case PROT_IPV6: 922 if (priv->conf.enableIPv6) 923 outHook = priv->hooks[HOOK_INDEX_IPV6]; 924 break; 925 } 926 927 bypass: 928 /* For unknown/inactive protocols, forward out the bypass hook */ 929 if (outHook == NULL) { 930 u_int16_t hdr[2]; 931 932 hdr[0] = htons(linkNum); 933 hdr[1] = htons((u_int16_t)proto); 934 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) { 935 NG_FREE_ITEM(item); 936 return (ENOBUFS); 937 } 938 outHook = priv->hooks[HOOK_INDEX_BYPASS]; 939 } 940 941 /* Forward frame */ 942 NG_FWD_NEW_DATA(error, item, outHook, m); 943 return (error); 944 } 945 946 /* 947 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM. 948 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0. 949 * 950 * If the frame is too big for the particular link, return EMSGSIZE. 951 */ 952 static int 953 ng_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 u_int16_t mru; 961 962 /* Extract mbuf */ 963 NGI_GET_M(item, m); 964 965 /* If not doing MP, map bundle virtual link to (the only) link */ 966 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink) 967 linkNum = priv->activeLinks[0]; 968 969 /* Get link pointer (optimization) */ 970 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ? 971 &priv->links[linkNum] : NULL; 972 973 /* Check link status (if real) */ 974 if (linkNum != NG_PPP_BUNDLE_LINKNUM) { 975 if (!bypass && !link->conf.enableLink) { 976 NG_FREE_M(m); 977 NG_FREE_ITEM(item); 978 return (ENXIO); 979 } 980 if (link->hook == NULL) { 981 NG_FREE_M(m); 982 NG_FREE_ITEM(item); 983 return (ENETDOWN); 984 } 985 } 986 987 /* Check peer's MRU for this link */ 988 mru = (link != NULL) ? link->conf.mru : priv->conf.mrru; 989 if (mru != 0 && m->m_pkthdr.len > mru) { 990 NG_FREE_M(m); 991 NG_FREE_ITEM(item); 992 return (EMSGSIZE); 993 } 994 995 /* Prepend protocol number, possibly compressed */ 996 if ((m = ng_ppp_addproto(m, proto, 997 linkNum == NG_PPP_BUNDLE_LINKNUM 998 || link->conf.enableProtoComp)) == NULL) { 999 NG_FREE_ITEM(item); 1000 return (ENOBUFS); 1001 } 1002 1003 /* Special handling for the MP virtual link */ 1004 if (linkNum == NG_PPP_BUNDLE_LINKNUM) { 1005 /* discard the queue item */ 1006 NG_FREE_ITEM(item); 1007 return ng_ppp_mp_output(node, m); 1008 } 1009 1010 /* Prepend address and control field (unless compressed) */ 1011 if (proto == PROT_LCP || !link->conf.enableACFComp) { 1012 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) { 1013 NG_FREE_ITEM(item); 1014 return (ENOBUFS); 1015 } 1016 } 1017 1018 /* Deliver frame */ 1019 len = m->m_pkthdr.len; 1020 NG_FWD_NEW_DATA(error, item, link->hook, m); 1021 1022 /* Update stats and 'bytes in queue' counter */ 1023 if (error == 0) { 1024 link->stats.xmitFrames++; 1025 link->stats.xmitOctets += len; 1026 link->bytesInQueue += len; 1027 getmicrouptime(&link->lastWrite); 1028 } 1029 return error; 1030 } 1031 1032 /* 1033 * Handle an incoming multi-link fragment 1034 * 1035 * The fragment reassembly algorithm is somewhat complex. This is mainly 1036 * because we are required not to reorder the reconstructed packets, yet 1037 * fragments are only guaranteed to arrive in order on a per-link basis. 1038 * In other words, when we have a complete packet ready, but the previous 1039 * packet is still incomplete, we have to decide between delivering the 1040 * complete packet and throwing away the incomplete one, or waiting to 1041 * see if the remainder of the incomplete one arrives, at which time we 1042 * can deliver both packets, in order. 1043 * 1044 * This problem is exacerbated by "sequence number slew", which is when 1045 * the sequence numbers coming in from different links are far apart from 1046 * each other. In particular, certain unnamed equipment (*cough* Ascend) 1047 * has been seen to generate sequence number slew of up to 10 on an ISDN 1048 * 2B-channel MP link. There is nothing invalid about sequence number slew 1049 * but it makes the reasssembly process have to work harder. 1050 * 1051 * However, the peer is required to transmit fragments in order on each 1052 * link. That means if we define MSEQ as the minimum over all links of 1053 * the highest sequence number received on that link, then we can always 1054 * give up any hope of receiving a fragment with sequence number < MSEQ in 1055 * the future (all of this using 'wraparound' sequence number space). 1056 * Therefore we can always immediately throw away incomplete packets 1057 * missing fragments with sequence numbers < MSEQ. 1058 * 1059 * Here is an overview of our algorithm: 1060 * 1061 * o Received fragments are inserted into a queue, for which we 1062 * maintain these invariants between calls to this function: 1063 * 1064 * - Fragments are ordered in the queue by sequence number 1065 * - If a complete packet is at the head of the queue, then 1066 * the first fragment in the packet has seq# > MSEQ + 1 1067 * (otherwise, we could deliver it immediately) 1068 * - If any fragments have seq# < MSEQ, then they are necessarily 1069 * part of a packet whose missing seq#'s are all > MSEQ (otherwise, 1070 * we can throw them away because they'll never be completed) 1071 * - The queue contains at most MP_MAX_QUEUE_LEN fragments 1072 * 1073 * o We have a periodic timer that checks the queue for the first 1074 * complete packet that has been sitting in the queue "too long". 1075 * When one is detected, all previous (incomplete) fragments are 1076 * discarded, their missing fragments are declared lost and MSEQ 1077 * is increased. 1078 * 1079 * o If we recieve a fragment with seq# < MSEQ, we throw it away 1080 * because we've already delcared it lost. 1081 * 1082 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM. 1083 */ 1084 static int 1085 ng_ppp_mp_input(node_p node, int linkNum, item_p item) 1086 { 1087 const priv_p priv = NG_NODE_PRIVATE(node); 1088 struct ng_ppp_link *const link = &priv->links[linkNum]; 1089 struct ng_ppp_frag frag0, *frag = &frag0; 1090 struct ng_ppp_frag *qent; 1091 int i, diff, inserted; 1092 struct mbuf *m; 1093 1094 NGI_GET_M(item, m); 1095 NG_FREE_ITEM(item); 1096 /* Stats */ 1097 priv->bundleStats.recvFrames++; 1098 priv->bundleStats.recvOctets += m->m_pkthdr.len; 1099 1100 /* Extract fragment information from MP header */ 1101 if (priv->conf.recvShortSeq) { 1102 u_int16_t shdr; 1103 1104 if (m->m_pkthdr.len < 2) { 1105 link->stats.runts++; 1106 NG_FREE_M(m); 1107 return (EINVAL); 1108 } 1109 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) 1110 return (ENOBUFS); 1111 1112 shdr = ntohs(*mtod(m, u_int16_t *)); 1113 frag->seq = MP_SHORT_EXTEND(shdr); 1114 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0; 1115 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0; 1116 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq); 1117 m_adj(m, 2); 1118 } else { 1119 u_int32_t lhdr; 1120 1121 if (m->m_pkthdr.len < 4) { 1122 link->stats.runts++; 1123 NG_FREE_M(m); 1124 return (EINVAL); 1125 } 1126 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) 1127 return (ENOBUFS); 1128 1129 lhdr = ntohl(*mtod(m, u_int32_t *)); 1130 frag->seq = MP_LONG_EXTEND(lhdr); 1131 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0; 1132 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0; 1133 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq); 1134 m_adj(m, 4); 1135 } 1136 frag->data = m; 1137 getmicrouptime(&frag->timestamp); 1138 1139 /* If sequence number is < MSEQ, we've already declared this 1140 fragment as lost, so we have no choice now but to drop it */ 1141 if (diff < 0) { 1142 link->stats.dropFragments++; 1143 NG_FREE_M(m); 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_ppp_frag_process(node); 1162 return (ENOMEM); 1163 } 1164 *frag = frag0; 1165 1166 /* Add fragment to queue, which is sorted by sequence number */ 1167 inserted = 0; 1168 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) { 1169 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq); 1170 if (diff > 0) { 1171 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent); 1172 inserted = 1; 1173 break; 1174 } else if (diff == 0) { /* should never happen! */ 1175 link->stats.dupFragments++; 1176 NG_FREE_M(frag->data); 1177 FREE(frag, M_NETGRAPH_PPP); 1178 return (EINVAL); 1179 } 1180 } 1181 if (!inserted) 1182 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent); 1183 priv->qlen++; 1184 1185 /* Process the queue */ 1186 return ng_ppp_frag_process(node); 1187 } 1188 1189 /* 1190 * Examine our list of fragments, and determine if there is a 1191 * complete and deliverable packet at the head of the list. 1192 * Return 1 if so, zero otherwise. 1193 */ 1194 static int 1195 ng_ppp_check_packet(node_p node) 1196 { 1197 const priv_p priv = NG_NODE_PRIVATE(node); 1198 struct ng_ppp_frag *qent, *qnext; 1199 1200 /* Check for empty queue */ 1201 if (TAILQ_EMPTY(&priv->frags)) 1202 return (0); 1203 1204 /* Check first fragment is the start of a deliverable packet */ 1205 qent = TAILQ_FIRST(&priv->frags); 1206 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1) 1207 return (0); 1208 1209 /* Check that all the fragments are there */ 1210 while (!qent->last) { 1211 qnext = TAILQ_NEXT(qent, f_qent); 1212 if (qnext == NULL) /* end of queue */ 1213 return (0); 1214 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)) 1215 return (0); 1216 qent = qnext; 1217 } 1218 1219 /* Got one */ 1220 return (1); 1221 } 1222 1223 /* 1224 * Pull a completed packet off the head of the incoming fragment queue. 1225 * This assumes there is a completed packet there to pull off. 1226 */ 1227 static void 1228 ng_ppp_get_packet(node_p node, struct mbuf **mp) 1229 { 1230 const priv_p priv = NG_NODE_PRIVATE(node); 1231 struct ng_ppp_frag *qent, *qnext; 1232 struct mbuf *m = NULL, *tail; 1233 1234 qent = TAILQ_FIRST(&priv->frags); 1235 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first, 1236 ("%s: no packet", __func__)); 1237 for (tail = NULL; qent != NULL; qent = qnext) { 1238 qnext = TAILQ_NEXT(qent, f_qent); 1239 KASSERT(!TAILQ_EMPTY(&priv->frags), 1240 ("%s: empty q", __func__)); 1241 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1242 if (tail == NULL) 1243 tail = m = qent->data; 1244 else { 1245 m->m_pkthdr.len += qent->data->m_pkthdr.len; 1246 tail->m_next = qent->data; 1247 } 1248 while (tail->m_next != NULL) 1249 tail = tail->m_next; 1250 if (qent->last) 1251 qnext = NULL; 1252 FREE(qent, M_NETGRAPH_PPP); 1253 priv->qlen--; 1254 } 1255 *mp = m; 1256 } 1257 1258 /* 1259 * Trim fragments from the queue whose packets can never be completed. 1260 * This assumes a complete packet is NOT at the beginning of the queue. 1261 * Returns 1 if fragments were removed, zero otherwise. 1262 */ 1263 static int 1264 ng_ppp_frag_trim(node_p node) 1265 { 1266 const priv_p priv = NG_NODE_PRIVATE(node); 1267 struct ng_ppp_frag *qent, *qnext = NULL; 1268 int removed = 0; 1269 1270 /* Scan for "dead" fragments and remove them */ 1271 while (1) { 1272 int dead = 0; 1273 1274 /* If queue is empty, we're done */ 1275 if (TAILQ_EMPTY(&priv->frags)) 1276 break; 1277 1278 /* Determine whether first fragment can ever be completed */ 1279 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1280 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0) 1281 break; 1282 qnext = TAILQ_NEXT(qent, f_qent); 1283 KASSERT(qnext != NULL, 1284 ("%s: last frag < MSEQ?", __func__)); 1285 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq) 1286 || qent->last || qnext->first) { 1287 dead = 1; 1288 break; 1289 } 1290 } 1291 if (!dead) 1292 break; 1293 1294 /* Remove fragment and all others in the same packet */ 1295 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) { 1296 KASSERT(!TAILQ_EMPTY(&priv->frags), 1297 ("%s: empty q", __func__)); 1298 priv->bundleStats.dropFragments++; 1299 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1300 NG_FREE_M(qent->data); 1301 FREE(qent, M_NETGRAPH_PPP); 1302 priv->qlen--; 1303 removed = 1; 1304 } 1305 } 1306 return (removed); 1307 } 1308 1309 /* 1310 * Run the queue, restoring the queue invariants 1311 */ 1312 static int 1313 ng_ppp_frag_process(node_p node) 1314 { 1315 const priv_p priv = NG_NODE_PRIVATE(node); 1316 struct mbuf *m; 1317 item_p item; 1318 1319 /* Deliver any deliverable packets */ 1320 while (ng_ppp_check_packet(node)) { 1321 ng_ppp_get_packet(node, &m); 1322 item = ng_package_data(m, NULL); 1323 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1324 } 1325 1326 /* Delete dead fragments and try again */ 1327 if (ng_ppp_frag_trim(node)) { 1328 while (ng_ppp_check_packet(node)) { 1329 ng_ppp_get_packet(node, &m); 1330 item = ng_package_data(m, NULL); 1331 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1332 } 1333 } 1334 1335 /* Check for stale fragments while we're here */ 1336 ng_ppp_frag_checkstale(node); 1337 1338 /* Check queue length */ 1339 if (priv->qlen > MP_MAX_QUEUE_LEN) { 1340 struct ng_ppp_frag *qent; 1341 int i; 1342 1343 /* Get oldest fragment */ 1344 KASSERT(!TAILQ_EMPTY(&priv->frags), 1345 ("%s: empty q", __func__)); 1346 qent = TAILQ_FIRST(&priv->frags); 1347 1348 /* Bump MSEQ if necessary */ 1349 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) { 1350 priv->mseq = qent->seq; 1351 for (i = 0; i < priv->numActiveLinks; i++) { 1352 struct ng_ppp_link *const alink = 1353 &priv->links[priv->activeLinks[i]]; 1354 1355 if (MP_RECV_SEQ_DIFF(priv, 1356 alink->seq, priv->mseq) < 0) 1357 alink->seq = priv->mseq; 1358 } 1359 } 1360 1361 /* Drop it */ 1362 priv->bundleStats.dropFragments++; 1363 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1364 NG_FREE_M(qent->data); 1365 FREE(qent, M_NETGRAPH_PPP); 1366 priv->qlen--; 1367 1368 /* Process queue again */ 1369 return ng_ppp_frag_process(node); 1370 } 1371 1372 /* Done */ 1373 return (0); 1374 } 1375 1376 /* 1377 * Check for 'stale' completed packets that need to be delivered 1378 * 1379 * If a link goes down or has a temporary failure, MSEQ can get 1380 * "stuck", because no new incoming fragments appear on that link. 1381 * This can cause completed packets to never get delivered if 1382 * their sequence numbers are all > MSEQ + 1. 1383 * 1384 * This routine checks how long all of the completed packets have 1385 * been sitting in the queue, and if too long, removes fragments 1386 * from the queue and increments MSEQ to allow them to be delivered. 1387 */ 1388 static void 1389 ng_ppp_frag_checkstale(node_p node) 1390 { 1391 const priv_p priv = NG_NODE_PRIVATE(node); 1392 struct ng_ppp_frag *qent, *beg, *end; 1393 struct timeval now, age; 1394 struct mbuf *m; 1395 int i, seq; 1396 item_p item; 1397 int endseq; 1398 1399 now.tv_sec = 0; /* uninitialized state */ 1400 while (1) { 1401 1402 /* If queue is empty, we're done */ 1403 if (TAILQ_EMPTY(&priv->frags)) 1404 break; 1405 1406 /* Find the first complete packet in the queue */ 1407 beg = end = NULL; 1408 seq = TAILQ_FIRST(&priv->frags)->seq; 1409 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1410 if (qent->first) 1411 beg = qent; 1412 else if (qent->seq != seq) 1413 beg = NULL; 1414 if (beg != NULL && qent->last) { 1415 end = qent; 1416 break; 1417 } 1418 seq = MP_NEXT_RECV_SEQ(priv, seq); 1419 } 1420 1421 /* If none found, exit */ 1422 if (end == NULL) 1423 break; 1424 1425 /* Get current time (we assume we've been up for >= 1 second) */ 1426 if (now.tv_sec == 0) 1427 getmicrouptime(&now); 1428 1429 /* Check if packet has been queued too long */ 1430 age = now; 1431 timevalsub(&age, &beg->timestamp); 1432 if (timevalcmp(&age, &ng_ppp_max_staleness, < )) 1433 break; 1434 1435 /* Throw away junk fragments in front of the completed packet */ 1436 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) { 1437 KASSERT(!TAILQ_EMPTY(&priv->frags), 1438 ("%s: empty q", __func__)); 1439 priv->bundleStats.dropFragments++; 1440 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1441 NG_FREE_M(qent->data); 1442 FREE(qent, M_NETGRAPH_PPP); 1443 priv->qlen--; 1444 } 1445 1446 /* Extract completed packet */ 1447 endseq = end->seq; 1448 ng_ppp_get_packet(node, &m); 1449 1450 /* Bump MSEQ if necessary */ 1451 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, endseq) < 0) { 1452 priv->mseq = endseq; 1453 for (i = 0; i < priv->numActiveLinks; i++) { 1454 struct ng_ppp_link *const alink = 1455 &priv->links[priv->activeLinks[i]]; 1456 1457 if (MP_RECV_SEQ_DIFF(priv, 1458 alink->seq, priv->mseq) < 0) 1459 alink->seq = priv->mseq; 1460 } 1461 } 1462 1463 /* Deliver packet */ 1464 item = ng_package_data(m, NULL); 1465 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1466 } 1467 } 1468 1469 /* 1470 * Periodically call ng_ppp_frag_checkstale() 1471 */ 1472 static void 1473 ng_ppp_frag_timeout(void *arg) 1474 { 1475 const node_p node = arg; 1476 const priv_p priv = NG_NODE_PRIVATE(node); 1477 int s = splnet(); 1478 1479 /* Handle the race where shutdown happens just before splnet() above */ 1480 if (NG_NODE_NOT_VALID(node)) { 1481 NG_NODE_UNREF(node); 1482 splx(s); 1483 return; 1484 } 1485 1486 /* Reset timer state after timeout */ 1487 KASSERT(priv->timerActive, ("%s: !timerActive", __func__)); 1488 priv->timerActive = 0; 1489 KASSERT(node->nd_refs > 1, ("%s: nd_refs=%d", __func__, node->nd_refs)); 1490 NG_NODE_UNREF(node); 1491 1492 /* Start timer again */ 1493 ng_ppp_start_frag_timer(node); 1494 1495 /* Scan the fragment queue */ 1496 ng_ppp_frag_checkstale(node); 1497 splx(s); 1498 } 1499 1500 /* 1501 * Deliver a frame out on the bundle, i.e., figure out how to fragment 1502 * the frame across the individual PPP links and do so. 1503 */ 1504 static int 1505 ng_ppp_mp_output(node_p node, struct mbuf *m) 1506 { 1507 const priv_p priv = NG_NODE_PRIVATE(node); 1508 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4; 1509 int distrib[NG_PPP_MAX_LINKS]; 1510 int firstFragment; 1511 int activeLinkNum; 1512 item_p item; 1513 1514 /* At least one link must be active */ 1515 if (priv->numActiveLinks == 0) { 1516 NG_FREE_M(m); 1517 return (ENETDOWN); 1518 } 1519 1520 /* Round-robin strategy */ 1521 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) { 1522 activeLinkNum = priv->lastLink++ % priv->numActiveLinks; 1523 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0])); 1524 distrib[activeLinkNum] = m->m_pkthdr.len; 1525 goto deliver; 1526 } 1527 1528 /* Strategy when all links are equivalent (optimize the common case) */ 1529 if (priv->allLinksEqual) { 1530 const int fraction = m->m_pkthdr.len / priv->numActiveLinks; 1531 int i, remain; 1532 1533 for (i = 0; i < priv->numActiveLinks; i++) 1534 distrib[priv->lastLink++ % priv->numActiveLinks] 1535 = fraction; 1536 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks); 1537 while (remain > 0) { 1538 distrib[priv->lastLink++ % priv->numActiveLinks]++; 1539 remain--; 1540 } 1541 goto deliver; 1542 } 1543 1544 /* Strategy when all links are not equivalent */ 1545 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib); 1546 1547 deliver: 1548 /* Update stats */ 1549 priv->bundleStats.xmitFrames++; 1550 priv->bundleStats.xmitOctets += m->m_pkthdr.len; 1551 1552 /* Send alloted portions of frame out on the link(s) */ 1553 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1; 1554 activeLinkNum >= 0; activeLinkNum--) { 1555 const int linkNum = priv->activeLinks[activeLinkNum]; 1556 struct ng_ppp_link *const link = &priv->links[linkNum]; 1557 1558 /* Deliver fragment(s) out the next link */ 1559 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) { 1560 int len, lastFragment, error; 1561 struct mbuf *m2; 1562 1563 /* Calculate fragment length; don't exceed link MTU */ 1564 len = distrib[activeLinkNum]; 1565 if (len > link->conf.mru - hdr_len) 1566 len = link->conf.mru - hdr_len; 1567 distrib[activeLinkNum] -= len; 1568 lastFragment = (len == m->m_pkthdr.len); 1569 1570 /* Split off next fragment as "m2" */ 1571 m2 = m; 1572 if (!lastFragment) { 1573 struct mbuf *n = m_split(m, len, M_DONTWAIT); 1574 1575 if (n == NULL) { 1576 NG_FREE_M(m); 1577 return (ENOMEM); 1578 } 1579 m = n; 1580 } 1581 1582 /* Prepend MP header */ 1583 if (priv->conf.xmitShortSeq) { 1584 u_int16_t shdr; 1585 1586 shdr = priv->xseq; 1587 priv->xseq = 1588 (priv->xseq + 1) & MP_SHORT_SEQ_MASK; 1589 if (firstFragment) 1590 shdr |= MP_SHORT_FIRST_FLAG; 1591 if (lastFragment) 1592 shdr |= MP_SHORT_LAST_FLAG; 1593 shdr = htons(shdr); 1594 m2 = ng_ppp_prepend(m2, &shdr, 2); 1595 } else { 1596 u_int32_t lhdr; 1597 1598 lhdr = priv->xseq; 1599 priv->xseq = 1600 (priv->xseq + 1) & MP_LONG_SEQ_MASK; 1601 if (firstFragment) 1602 lhdr |= MP_LONG_FIRST_FLAG; 1603 if (lastFragment) 1604 lhdr |= MP_LONG_LAST_FLAG; 1605 lhdr = htonl(lhdr); 1606 m2 = ng_ppp_prepend(m2, &lhdr, 4); 1607 } 1608 if (m2 == NULL) { 1609 if (!lastFragment) 1610 m_freem(m); 1611 return (ENOBUFS); 1612 } 1613 1614 /* Send fragment */ 1615 item = ng_package_data(m2, NULL); 1616 error = ng_ppp_output(node, 0, PROT_MP, linkNum, item); 1617 if (error != 0) { 1618 if (!lastFragment) 1619 NG_FREE_M(m); 1620 return (error); 1621 } 1622 } 1623 } 1624 1625 /* Done */ 1626 return (0); 1627 } 1628 1629 /* 1630 * Computing the optimal fragmentation 1631 * ----------------------------------- 1632 * 1633 * This routine tries to compute the optimal fragmentation pattern based 1634 * on each link's latency, bandwidth, and calculated additional latency. 1635 * The latter quantity is the additional latency caused by previously 1636 * written data that has not been transmitted yet. 1637 * 1638 * This algorithm is only useful when not all of the links have the 1639 * same latency and bandwidth values. 1640 * 1641 * The essential idea is to make the last bit of each fragment of the 1642 * frame arrive at the opposite end at the exact same time. This greedy 1643 * algorithm is optimal, in that no other scheduling could result in any 1644 * packet arriving any sooner unless packets are delivered out of order. 1645 * 1646 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and 1647 * latency l_i (in miliseconds). Consider the function function f_i(t) 1648 * which is equal to the number of bytes that will have arrived at 1649 * the peer after t miliseconds if we start writing continuously at 1650 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i). 1651 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i). 1652 * Note that the y-intersect is always <= zero because latency can't be 1653 * negative. Note also that really the function is f_i(t) except when 1654 * f_i(t) is negative, in which case the function is zero. To take 1655 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }. 1656 * So the actual number of bytes that will have arrived at the peer after 1657 * t miliseconds is f_i(t) * Q_i(t). 1658 * 1659 * At any given time, each link has some additional latency a_i >= 0 1660 * due to previously written fragment(s) which are still in the queue. 1661 * This value is easily computed from the time since last transmission, 1662 * the previous latency value, the number of bytes written, and the 1663 * link's bandwidth. 1664 * 1665 * Assume that l_i includes any a_i already, and that the links are 1666 * sorted by latency, so that l_i <= l_{i+1}. 1667 * 1668 * Let N be the total number of bytes in the current frame we are sending. 1669 * 1670 * Suppose we were to start writing bytes at time t = 0 on all links 1671 * simultaneously, which is the most we can possibly do. Then let 1672 * F(t) be equal to the total number of bytes received by the peer 1673 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)). 1674 * 1675 * Our goal is simply this: fragment the frame across the links such 1676 * that the peer is able to reconstruct the completed frame as soon as 1677 * possible, i.e., at the least possible value of t. Call this value t_0. 1678 * 1679 * Then it follows that F(t_0) = N. Our strategy is first to find the value 1680 * of t_0, and then deduce how many bytes to write to each link. 1681 * 1682 * Rewriting F(t_0): 1683 * 1684 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) ) 1685 * 1686 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will 1687 * lie in one of these ranges. To find it, we just need to find the i such 1688 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values 1689 * for Q_i() in this range, plug in the remaining values, solving for t_0. 1690 * 1691 * Once t_0 is known, then the number of bytes to send on link i is 1692 * just f_i(t_0) * Q_i(t_0). 1693 * 1694 * In other words, we start allocating bytes to the links one at a time. 1695 * We keep adding links until the frame is completely sent. Some links 1696 * may not get any bytes because their latency is too high. 1697 * 1698 * Is all this work really worth the trouble? Depends on the situation. 1699 * The bigger the ratio of computer speed to link speed, and the more 1700 * important total bundle latency is (e.g., for interactive response time), 1701 * the more it's worth it. There is however the cost of calling this 1702 * function for every frame. The running time is O(n^2) where n is the 1703 * number of links that receive a non-zero number of bytes. 1704 * 1705 * Since latency is measured in miliseconds, the "resolution" of this 1706 * algorithm is one milisecond. 1707 * 1708 * To avoid this algorithm altogether, configure all links to have the 1709 * same latency and bandwidth. 1710 */ 1711 static void 1712 ng_ppp_mp_strategy(node_p node, int len, int *distrib) 1713 { 1714 const priv_p priv = NG_NODE_PRIVATE(node); 1715 int latency[NG_PPP_MAX_LINKS]; 1716 int sortByLatency[NG_PPP_MAX_LINKS]; 1717 int activeLinkNum; 1718 int t0, total, topSum, botSum; 1719 struct timeval now; 1720 int i, numFragments; 1721 1722 /* If only one link, this gets real easy */ 1723 if (priv->numActiveLinks == 1) { 1724 distrib[0] = len; 1725 return; 1726 } 1727 1728 /* Get current time */ 1729 getmicrouptime(&now); 1730 1731 /* Compute latencies for each link at this point in time */ 1732 for (activeLinkNum = 0; 1733 activeLinkNum < priv->numActiveLinks; activeLinkNum++) { 1734 struct ng_ppp_link *alink; 1735 struct timeval diff; 1736 int xmitBytes; 1737 1738 /* Start with base latency value */ 1739 alink = &priv->links[priv->activeLinks[activeLinkNum]]; 1740 latency[activeLinkNum] = alink->conf.latency; 1741 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */ 1742 1743 /* Any additional latency? */ 1744 if (alink->bytesInQueue == 0) 1745 continue; 1746 1747 /* Compute time delta since last write */ 1748 diff = now; 1749 timevalsub(&diff, &alink->lastWrite); 1750 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */ 1751 alink->bytesInQueue = 0; 1752 continue; 1753 } 1754 1755 /* How many bytes could have transmitted since last write? */ 1756 xmitBytes = (alink->conf.bandwidth * diff.tv_sec) 1757 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100; 1758 alink->bytesInQueue -= xmitBytes; 1759 if (alink->bytesInQueue < 0) 1760 alink->bytesInQueue = 0; 1761 else 1762 latency[activeLinkNum] += 1763 (100 * alink->bytesInQueue) / alink->conf.bandwidth; 1764 } 1765 1766 /* Sort active links by latency */ 1767 compareLatencies = latency; 1768 qsort(sortByLatency, 1769 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp); 1770 compareLatencies = NULL; 1771 1772 /* Find the interval we need (add links in sortByLatency[] order) */ 1773 for (numFragments = 1; 1774 numFragments < priv->numActiveLinks; numFragments++) { 1775 for (total = i = 0; i < numFragments; i++) { 1776 int flowTime; 1777 1778 flowTime = latency[sortByLatency[numFragments]] 1779 - latency[sortByLatency[i]]; 1780 total += ((flowTime * priv->links[ 1781 priv->activeLinks[sortByLatency[i]]].conf.bandwidth) 1782 + 99) / 100; 1783 } 1784 if (total >= len) 1785 break; 1786 } 1787 1788 /* Solve for t_0 in that interval */ 1789 for (topSum = botSum = i = 0; i < numFragments; i++) { 1790 int bw = priv->links[ 1791 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1792 1793 topSum += latency[sortByLatency[i]] * bw; /* / 100 */ 1794 botSum += bw; /* / 100 */ 1795 } 1796 t0 = ((len * 100) + topSum + botSum / 2) / botSum; 1797 1798 /* Compute f_i(t_0) all i */ 1799 bzero(distrib, priv->numActiveLinks * sizeof(*distrib)); 1800 for (total = i = 0; i < numFragments; i++) { 1801 int bw = priv->links[ 1802 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1803 1804 distrib[sortByLatency[i]] = 1805 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100; 1806 total += distrib[sortByLatency[i]]; 1807 } 1808 1809 /* Deal with any rounding error */ 1810 if (total < len) { 1811 struct ng_ppp_link *fastLink = 1812 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1813 int fast = 0; 1814 1815 /* Find the fastest link */ 1816 for (i = 1; i < numFragments; i++) { 1817 struct ng_ppp_link *const link = 1818 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1819 1820 if (link->conf.bandwidth > fastLink->conf.bandwidth) { 1821 fast = i; 1822 fastLink = link; 1823 } 1824 } 1825 distrib[sortByLatency[fast]] += len - total; 1826 } else while (total > len) { 1827 struct ng_ppp_link *slowLink = 1828 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1829 int delta, slow = 0; 1830 1831 /* Find the slowest link that still has bytes to remove */ 1832 for (i = 1; i < numFragments; i++) { 1833 struct ng_ppp_link *const link = 1834 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1835 1836 if (distrib[sortByLatency[slow]] == 0 1837 || (distrib[sortByLatency[i]] > 0 1838 && link->conf.bandwidth < 1839 slowLink->conf.bandwidth)) { 1840 slow = i; 1841 slowLink = link; 1842 } 1843 } 1844 delta = total - len; 1845 if (delta > distrib[sortByLatency[slow]]) 1846 delta = distrib[sortByLatency[slow]]; 1847 distrib[sortByLatency[slow]] -= delta; 1848 total -= delta; 1849 } 1850 } 1851 1852 /* 1853 * Compare two integers 1854 */ 1855 static int 1856 ng_ppp_intcmp(const void *v1, const void *v2) 1857 { 1858 const int index1 = *((const int *) v1); 1859 const int index2 = *((const int *) v2); 1860 1861 return compareLatencies[index1] - compareLatencies[index2]; 1862 } 1863 1864 /* 1865 * Prepend a possibly compressed PPP protocol number in front of a frame 1866 */ 1867 static struct mbuf * 1868 ng_ppp_addproto(struct mbuf *m, int proto, int compOK) 1869 { 1870 if (compOK && PROT_COMPRESSABLE(proto)) { 1871 u_char pbyte = (u_char)proto; 1872 1873 return ng_ppp_prepend(m, &pbyte, 1); 1874 } else { 1875 u_int16_t pword = htons((u_int16_t)proto); 1876 1877 return ng_ppp_prepend(m, &pword, 2); 1878 } 1879 } 1880 1881 /* 1882 * Prepend some bytes to an mbuf 1883 */ 1884 static struct mbuf * 1885 ng_ppp_prepend(struct mbuf *m, const void *buf, int len) 1886 { 1887 M_PREPEND(m, len, M_DONTWAIT); 1888 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL)) 1889 return (NULL); 1890 bcopy(buf, mtod(m, u_char *), len); 1891 return (m); 1892 } 1893 1894 /* 1895 * Update private information that is derived from other private information 1896 */ 1897 static void 1898 ng_ppp_update(node_p node, int newConf) 1899 { 1900 const priv_p priv = NG_NODE_PRIVATE(node); 1901 int i; 1902 1903 /* Update active status for VJ Compression */ 1904 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL 1905 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL 1906 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL 1907 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL; 1908 1909 /* Increase latency for each link an amount equal to one MP header */ 1910 if (newConf) { 1911 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1912 int hdrBytes; 1913 1914 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2) 1915 + (priv->links[i].conf.enableProtoComp ? 1 : 2) 1916 + (priv->conf.xmitShortSeq ? 2 : 4); 1917 priv->links[i].conf.latency += 1918 ((hdrBytes * priv->links[i].conf.bandwidth) + 50) 1919 / 100; 1920 } 1921 } 1922 1923 /* Update list of active links */ 1924 bzero(&priv->activeLinks, sizeof(priv->activeLinks)); 1925 priv->numActiveLinks = 0; 1926 priv->allLinksEqual = 1; 1927 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1928 struct ng_ppp_link *const link = &priv->links[i]; 1929 1930 /* Is link active? */ 1931 if (link->conf.enableLink && link->hook != NULL) { 1932 struct ng_ppp_link *link0; 1933 1934 /* Add link to list of active links */ 1935 priv->activeLinks[priv->numActiveLinks++] = i; 1936 link0 = &priv->links[priv->activeLinks[0]]; 1937 1938 /* Determine if all links are still equal */ 1939 if (link->conf.latency != link0->conf.latency 1940 || link->conf.bandwidth != link0->conf.bandwidth) 1941 priv->allLinksEqual = 0; 1942 1943 /* Initialize rec'd sequence number */ 1944 if (link->seq == MP_NOSEQ) { 1945 link->seq = (link == link0) ? 1946 MP_INITIAL_SEQ : link0->seq; 1947 } 1948 } else 1949 link->seq = MP_NOSEQ; 1950 } 1951 1952 /* Update MP state as multi-link is active or not */ 1953 if (priv->conf.enableMultilink && priv->numActiveLinks > 0) 1954 ng_ppp_start_frag_timer(node); 1955 else { 1956 ng_ppp_stop_frag_timer(node); 1957 ng_ppp_frag_reset(node); 1958 priv->xseq = MP_INITIAL_SEQ; 1959 priv->mseq = MP_INITIAL_SEQ; 1960 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1961 struct ng_ppp_link *const link = &priv->links[i]; 1962 1963 bzero(&link->lastWrite, sizeof(link->lastWrite)); 1964 link->bytesInQueue = 0; 1965 link->seq = MP_NOSEQ; 1966 } 1967 } 1968 } 1969 1970 /* 1971 * Determine if a new configuration would represent a valid change 1972 * from the current configuration and link activity status. 1973 */ 1974 static int 1975 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf) 1976 { 1977 const priv_p priv = NG_NODE_PRIVATE(node); 1978 int i, newNumLinksActive; 1979 1980 /* Check per-link config and count how many links would be active */ 1981 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) { 1982 if (newConf->links[i].enableLink && priv->links[i].hook != NULL) 1983 newNumLinksActive++; 1984 if (!newConf->links[i].enableLink) 1985 continue; 1986 if (newConf->links[i].mru < MP_MIN_LINK_MRU) 1987 return (0); 1988 if (newConf->links[i].bandwidth == 0) 1989 return (0); 1990 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH) 1991 return (0); 1992 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY) 1993 return (0); 1994 } 1995 1996 /* Check bundle parameters */ 1997 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU) 1998 return (0); 1999 2000 /* Disallow changes to multi-link configuration while MP is active */ 2001 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) { 2002 if (!priv->conf.enableMultilink 2003 != !newConf->bund.enableMultilink 2004 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq 2005 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq) 2006 return (0); 2007 } 2008 2009 /* At most one link can be active unless multi-link is enabled */ 2010 if (!newConf->bund.enableMultilink && newNumLinksActive > 1) 2011 return (0); 2012 2013 /* Configuration change would be valid */ 2014 return (1); 2015 } 2016 2017 /* 2018 * Free all entries in the fragment queue 2019 */ 2020 static void 2021 ng_ppp_frag_reset(node_p node) 2022 { 2023 const priv_p priv = NG_NODE_PRIVATE(node); 2024 struct ng_ppp_frag *qent, *qnext; 2025 2026 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) { 2027 qnext = TAILQ_NEXT(qent, f_qent); 2028 NG_FREE_M(qent->data); 2029 FREE(qent, M_NETGRAPH_PPP); 2030 } 2031 TAILQ_INIT(&priv->frags); 2032 priv->qlen = 0; 2033 } 2034 2035 /* 2036 * Start fragment queue timer 2037 */ 2038 static void 2039 ng_ppp_start_frag_timer(node_p node) 2040 { 2041 const priv_p priv = NG_NODE_PRIVATE(node); 2042 2043 if (!priv->timerActive) { 2044 priv->fragTimer = timeout(ng_ppp_frag_timeout, 2045 node, MP_FRAGTIMER_INTERVAL); 2046 priv->timerActive = 1; 2047 NG_NODE_REF(node); 2048 } 2049 } 2050 2051 /* 2052 * Stop fragment queue timer 2053 */ 2054 static void 2055 ng_ppp_stop_frag_timer(node_p node) 2056 { 2057 const priv_p priv = NG_NODE_PRIVATE(node); 2058 2059 if (priv->timerActive) { 2060 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer); 2061 priv->timerActive = 0; 2062 KASSERT(node->nd_refs > 1, 2063 ("%s: nd_refs=%d", __func__, node->nd_refs)); 2064 NG_NODE_UNREF(node); 2065 } 2066 } 2067 2068