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