1 /* 2 * ng_ppp.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-2000 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Author: Archie Cobbs <archie@freebsd.org> 39 * 40 * $FreeBSD$ 41 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $ 42 */ 43 44 /* 45 * PPP node type. 46 */ 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/kernel.h> 51 #include <sys/limits.h> 52 #include <sys/time.h> 53 #include <sys/mbuf.h> 54 #include <sys/malloc.h> 55 #include <sys/errno.h> 56 #include <sys/ctype.h> 57 58 #include <netgraph/ng_message.h> 59 #include <netgraph/netgraph.h> 60 #include <netgraph/ng_parse.h> 61 #include <netgraph/ng_ppp.h> 62 #include <netgraph/ng_vjc.h> 63 64 #ifdef NG_SEPARATE_MALLOC 65 MALLOC_DEFINE(M_NETGRAPH_PPP, "netgraph_ppp", "netgraph ppp node"); 66 #else 67 #define M_NETGRAPH_PPP M_NETGRAPH 68 #endif 69 70 #define PROT_VALID(p) (((p) & 0x0101) == 0x0001) 71 #define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000) 72 73 /* Some PPP protocol numbers we're interested in */ 74 #define PROT_APPLETALK 0x0029 75 #define PROT_COMPD 0x00fd 76 #define PROT_CRYPTD 0x0053 77 #define PROT_IP 0x0021 78 #define PROT_IPV6 0x0057 79 #define PROT_IPX 0x002b 80 #define PROT_LCP 0xc021 81 #define PROT_MP 0x003d 82 #define PROT_VJCOMP 0x002d 83 #define PROT_VJUNCOMP 0x002f 84 85 /* Multilink PPP definitions */ 86 #define MP_MIN_MRRU 1500 /* per RFC 1990 */ 87 #define MP_INITIAL_SEQ 0 /* per RFC 1990 */ 88 #define MP_MIN_LINK_MRU 32 89 90 #define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */ 91 #define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */ 92 #define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */ 93 #define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */ 94 95 #define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */ 96 #define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */ 97 #define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */ 98 #define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */ 99 100 #define MP_NOSEQ 0x7fffffff /* impossible sequence number */ 101 102 /* Sign extension of MP sequence numbers */ 103 #define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \ 104 ((s) | ~MP_SHORT_SEQ_MASK) \ 105 : ((s) & MP_SHORT_SEQ_MASK)) 106 #define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \ 107 ((s) | ~MP_LONG_SEQ_MASK) \ 108 : ((s) & MP_LONG_SEQ_MASK)) 109 110 /* Comparision of MP sequence numbers. Note: all sequence numbers 111 except priv->xseq are stored with the sign bit extended. */ 112 #define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y)) 113 #define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y)) 114 115 #define MP_RECV_SEQ_DIFF(priv,x,y) \ 116 ((priv)->conf.recvShortSeq ? \ 117 MP_SHORT_SEQ_DIFF((x), (y)) : \ 118 MP_LONG_SEQ_DIFF((x), (y))) 119 120 /* Increment receive sequence number */ 121 #define MP_NEXT_RECV_SEQ(priv,seq) \ 122 ((priv)->conf.recvShortSeq ? \ 123 MP_SHORT_EXTEND((seq) + 1) : \ 124 MP_LONG_EXTEND((seq) + 1)) 125 126 /* Don't fragment transmitted packets smaller than this */ 127 #define MP_MIN_FRAG_LEN 6 128 129 /* Maximum fragment reasssembly queue length */ 130 #define MP_MAX_QUEUE_LEN 128 131 132 /* Fragment queue scanner period */ 133 #define MP_FRAGTIMER_INTERVAL (hz/2) 134 135 /* We store incoming fragments this way */ 136 struct ng_ppp_frag { 137 int seq; /* fragment seq# */ 138 u_char first; /* First in packet? */ 139 u_char last; /* Last in packet? */ 140 struct timeval timestamp; /* time of reception */ 141 struct mbuf *data; /* Fragment data */ 142 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */ 143 }; 144 145 /* We use integer indicies to refer to the non-link hooks */ 146 static const char *const ng_ppp_hook_names[] = { 147 NG_PPP_HOOK_ATALK, 148 #define HOOK_INDEX_ATALK 0 149 NG_PPP_HOOK_BYPASS, 150 #define HOOK_INDEX_BYPASS 1 151 NG_PPP_HOOK_COMPRESS, 152 #define HOOK_INDEX_COMPRESS 2 153 NG_PPP_HOOK_ENCRYPT, 154 #define HOOK_INDEX_ENCRYPT 3 155 NG_PPP_HOOK_DECOMPRESS, 156 #define HOOK_INDEX_DECOMPRESS 4 157 NG_PPP_HOOK_DECRYPT, 158 #define HOOK_INDEX_DECRYPT 5 159 NG_PPP_HOOK_INET, 160 #define HOOK_INDEX_INET 6 161 NG_PPP_HOOK_IPX, 162 #define HOOK_INDEX_IPX 7 163 NG_PPP_HOOK_VJC_COMP, 164 #define HOOK_INDEX_VJC_COMP 8 165 NG_PPP_HOOK_VJC_IP, 166 #define HOOK_INDEX_VJC_IP 9 167 NG_PPP_HOOK_VJC_UNCOMP, 168 #define HOOK_INDEX_VJC_UNCOMP 10 169 NG_PPP_HOOK_VJC_VJIP, 170 #define HOOK_INDEX_VJC_VJIP 11 171 NG_PPP_HOOK_IPV6, 172 #define HOOK_INDEX_IPV6 12 173 NULL 174 #define HOOK_INDEX_MAX 13 175 }; 176 177 /* We store index numbers in the hook private pointer. The HOOK_INDEX() 178 for a hook is either the index (above) for normal hooks, or the ones 179 complement of the link number for link hooks. 180 XXX Not any more.. (what a hack) 181 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private)) 182 */ 183 184 /* Per-link private information */ 185 struct ng_ppp_link { 186 struct ng_ppp_link_conf conf; /* link configuration */ 187 hook_p hook; /* connection to link data */ 188 int32_t seq; /* highest rec'd seq# - MSEQ */ 189 u_int32_t latency; /* calculated link latency */ 190 struct timeval lastWrite; /* time of last write */ 191 int bytesInQueue; /* bytes in the output queue */ 192 struct ng_ppp_link_stat stats; /* Link stats */ 193 }; 194 195 /* Total per-node private information */ 196 struct ng_ppp_private { 197 struct ng_ppp_bund_conf conf; /* bundle config */ 198 struct ng_ppp_link_stat bundleStats; /* bundle stats */ 199 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */ 200 int32_t xseq; /* next out MP seq # */ 201 int32_t mseq; /* min links[i].seq */ 202 u_char vjCompHooked; /* VJ comp hooked up? */ 203 u_char allLinksEqual; /* all xmit the same? */ 204 u_int numActiveLinks; /* how many links up */ 205 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */ 206 u_int lastLink; /* for round robin */ 207 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */ 208 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */ 209 frags; 210 int qlen; /* fraq queue length */ 211 struct callout fragTimer; /* fraq queue check */ 212 }; 213 typedef struct ng_ppp_private *priv_p; 214 215 /* Netgraph node methods */ 216 static ng_constructor_t ng_ppp_constructor; 217 static ng_rcvmsg_t ng_ppp_rcvmsg; 218 static ng_shutdown_t ng_ppp_shutdown; 219 static ng_newhook_t ng_ppp_newhook; 220 static ng_rcvdata_t ng_ppp_rcvdata; 221 static ng_disconnect_t ng_ppp_disconnect; 222 223 /* Helper functions */ 224 static int ng_ppp_input(node_p node, int bypass, 225 int linkNum, item_p item); 226 static int ng_ppp_output(node_p node, int bypass, int proto, 227 int linkNum, item_p item); 228 static int ng_ppp_mp_input(node_p node, int linkNum, item_p item); 229 static int ng_ppp_check_packet(node_p node); 230 static void ng_ppp_get_packet(node_p node, struct mbuf **mp); 231 static int ng_ppp_frag_process(node_p node); 232 static int ng_ppp_frag_trim(node_p node); 233 static void ng_ppp_frag_timeout(node_p node, hook_p hook, void *arg1, 234 int arg2); 235 static void ng_ppp_frag_checkstale(node_p node); 236 static void ng_ppp_frag_reset(node_p node); 237 static int ng_ppp_mp_output(node_p node, struct mbuf *m); 238 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib); 239 static int ng_ppp_intcmp(void *latency, const void *v1, const void *v2); 240 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK); 241 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len); 242 static int ng_ppp_config_valid(node_p node, 243 const struct ng_ppp_node_conf *newConf); 244 static void ng_ppp_update(node_p node, int newConf); 245 static void ng_ppp_start_frag_timer(node_p node); 246 static void ng_ppp_stop_frag_timer(node_p node); 247 248 /* Parse type for struct ng_ppp_mp_state_type */ 249 static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = { 250 &ng_parse_hint32_type, 251 NG_PPP_MAX_LINKS 252 }; 253 static const struct ng_parse_type ng_ppp_rseq_array_type = { 254 &ng_parse_fixedarray_type, 255 &ng_ppp_rseq_array_info, 256 }; 257 static const struct ng_parse_struct_field ng_ppp_mp_state_type_fields[] 258 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type); 259 static const struct ng_parse_type ng_ppp_mp_state_type = { 260 &ng_parse_struct_type, 261 &ng_ppp_mp_state_type_fields 262 }; 263 264 /* Parse type for struct ng_ppp_link_conf */ 265 static const struct ng_parse_struct_field ng_ppp_link_type_fields[] 266 = NG_PPP_LINK_TYPE_INFO; 267 static const struct ng_parse_type ng_ppp_link_type = { 268 &ng_parse_struct_type, 269 &ng_ppp_link_type_fields 270 }; 271 272 /* Parse type for struct ng_ppp_bund_conf */ 273 static const struct ng_parse_struct_field ng_ppp_bund_type_fields[] 274 = NG_PPP_BUND_TYPE_INFO; 275 static const struct ng_parse_type ng_ppp_bund_type = { 276 &ng_parse_struct_type, 277 &ng_ppp_bund_type_fields 278 }; 279 280 /* Parse type for struct ng_ppp_node_conf */ 281 static const struct ng_parse_fixedarray_info ng_ppp_array_info = { 282 &ng_ppp_link_type, 283 NG_PPP_MAX_LINKS 284 }; 285 static const struct ng_parse_type ng_ppp_link_array_type = { 286 &ng_parse_fixedarray_type, 287 &ng_ppp_array_info, 288 }; 289 static const struct ng_parse_struct_field ng_ppp_conf_type_fields[] 290 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type); 291 static const struct ng_parse_type ng_ppp_conf_type = { 292 &ng_parse_struct_type, 293 &ng_ppp_conf_type_fields 294 }; 295 296 /* Parse type for struct ng_ppp_link_stat */ 297 static const struct ng_parse_struct_field ng_ppp_stats_type_fields[] 298 = NG_PPP_STATS_TYPE_INFO; 299 static const struct ng_parse_type ng_ppp_stats_type = { 300 &ng_parse_struct_type, 301 &ng_ppp_stats_type_fields 302 }; 303 304 /* List of commands and how to convert arguments to/from ASCII */ 305 static const struct ng_cmdlist ng_ppp_cmds[] = { 306 { 307 NGM_PPP_COOKIE, 308 NGM_PPP_SET_CONFIG, 309 "setconfig", 310 &ng_ppp_conf_type, 311 NULL 312 }, 313 { 314 NGM_PPP_COOKIE, 315 NGM_PPP_GET_CONFIG, 316 "getconfig", 317 NULL, 318 &ng_ppp_conf_type 319 }, 320 { 321 NGM_PPP_COOKIE, 322 NGM_PPP_GET_MP_STATE, 323 "getmpstate", 324 NULL, 325 &ng_ppp_mp_state_type 326 }, 327 { 328 NGM_PPP_COOKIE, 329 NGM_PPP_GET_LINK_STATS, 330 "getstats", 331 &ng_parse_int16_type, 332 &ng_ppp_stats_type 333 }, 334 { 335 NGM_PPP_COOKIE, 336 NGM_PPP_CLR_LINK_STATS, 337 "clrstats", 338 &ng_parse_int16_type, 339 NULL 340 }, 341 { 342 NGM_PPP_COOKIE, 343 NGM_PPP_GETCLR_LINK_STATS, 344 "getclrstats", 345 &ng_parse_int16_type, 346 &ng_ppp_stats_type 347 }, 348 { 0 } 349 }; 350 351 /* Node type descriptor */ 352 static struct ng_type ng_ppp_typestruct = { 353 .version = NG_ABI_VERSION, 354 .name = NG_PPP_NODE_TYPE, 355 .constructor = ng_ppp_constructor, 356 .rcvmsg = ng_ppp_rcvmsg, 357 .shutdown = ng_ppp_shutdown, 358 .newhook = ng_ppp_newhook, 359 .rcvdata = ng_ppp_rcvdata, 360 .disconnect = ng_ppp_disconnect, 361 .cmdlist = ng_ppp_cmds, 362 }; 363 NETGRAPH_INIT(ppp, &ng_ppp_typestruct); 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 ng_callout_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, 0)) == 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 if ((item = ng_package_data(m, NG_NOFLAGS)) != 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 if ((item = ng_package_data(m, NG_NOFLAGS)) != NULL) 1331 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, 1332 item); 1333 } 1334 } 1335 1336 /* Check for stale fragments while we're here */ 1337 ng_ppp_frag_checkstale(node); 1338 1339 /* Check queue length */ 1340 if (priv->qlen > MP_MAX_QUEUE_LEN) { 1341 struct ng_ppp_frag *qent; 1342 int i; 1343 1344 /* Get oldest fragment */ 1345 KASSERT(!TAILQ_EMPTY(&priv->frags), 1346 ("%s: empty q", __func__)); 1347 qent = TAILQ_FIRST(&priv->frags); 1348 1349 /* Bump MSEQ if necessary */ 1350 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) { 1351 priv->mseq = qent->seq; 1352 for (i = 0; i < priv->numActiveLinks; i++) { 1353 struct ng_ppp_link *const alink = 1354 &priv->links[priv->activeLinks[i]]; 1355 1356 if (MP_RECV_SEQ_DIFF(priv, 1357 alink->seq, priv->mseq) < 0) 1358 alink->seq = priv->mseq; 1359 } 1360 } 1361 1362 /* Drop it */ 1363 priv->bundleStats.dropFragments++; 1364 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1365 NG_FREE_M(qent->data); 1366 FREE(qent, M_NETGRAPH_PPP); 1367 priv->qlen--; 1368 1369 /* Process queue again */ 1370 return ng_ppp_frag_process(node); 1371 } 1372 1373 /* Done */ 1374 return (0); 1375 } 1376 1377 /* 1378 * Check for 'stale' completed packets that need to be delivered 1379 * 1380 * If a link goes down or has a temporary failure, MSEQ can get 1381 * "stuck", because no new incoming fragments appear on that link. 1382 * This can cause completed packets to never get delivered if 1383 * their sequence numbers are all > MSEQ + 1. 1384 * 1385 * This routine checks how long all of the completed packets have 1386 * been sitting in the queue, and if too long, removes fragments 1387 * from the queue and increments MSEQ to allow them to be delivered. 1388 */ 1389 static void 1390 ng_ppp_frag_checkstale(node_p node) 1391 { 1392 const priv_p priv = NG_NODE_PRIVATE(node); 1393 struct ng_ppp_frag *qent, *beg, *end; 1394 struct timeval now, age; 1395 struct mbuf *m; 1396 int i, seq; 1397 item_p item; 1398 int endseq; 1399 1400 now.tv_sec = 0; /* uninitialized state */ 1401 while (1) { 1402 1403 /* If queue is empty, we're done */ 1404 if (TAILQ_EMPTY(&priv->frags)) 1405 break; 1406 1407 /* Find the first complete packet in the queue */ 1408 beg = end = NULL; 1409 seq = TAILQ_FIRST(&priv->frags)->seq; 1410 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1411 if (qent->first) 1412 beg = qent; 1413 else if (qent->seq != seq) 1414 beg = NULL; 1415 if (beg != NULL && qent->last) { 1416 end = qent; 1417 break; 1418 } 1419 seq = MP_NEXT_RECV_SEQ(priv, seq); 1420 } 1421 1422 /* If none found, exit */ 1423 if (end == NULL) 1424 break; 1425 1426 /* Get current time (we assume we've been up for >= 1 second) */ 1427 if (now.tv_sec == 0) 1428 getmicrouptime(&now); 1429 1430 /* Check if packet has been queued too long */ 1431 age = now; 1432 timevalsub(&age, &beg->timestamp); 1433 if (timevalcmp(&age, &ng_ppp_max_staleness, < )) 1434 break; 1435 1436 /* Throw away junk fragments in front of the completed packet */ 1437 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) { 1438 KASSERT(!TAILQ_EMPTY(&priv->frags), 1439 ("%s: empty q", __func__)); 1440 priv->bundleStats.dropFragments++; 1441 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1442 NG_FREE_M(qent->data); 1443 FREE(qent, M_NETGRAPH_PPP); 1444 priv->qlen--; 1445 } 1446 1447 /* Extract completed packet */ 1448 endseq = end->seq; 1449 ng_ppp_get_packet(node, &m); 1450 1451 /* Bump MSEQ if necessary */ 1452 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, endseq) < 0) { 1453 priv->mseq = endseq; 1454 for (i = 0; i < priv->numActiveLinks; i++) { 1455 struct ng_ppp_link *const alink = 1456 &priv->links[priv->activeLinks[i]]; 1457 1458 if (MP_RECV_SEQ_DIFF(priv, 1459 alink->seq, priv->mseq) < 0) 1460 alink->seq = priv->mseq; 1461 } 1462 } 1463 1464 /* Deliver packet */ 1465 if ((item = ng_package_data(m, NG_NOFLAGS)) != NULL) 1466 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, item); 1467 } 1468 } 1469 1470 /* 1471 * Periodically call ng_ppp_frag_checkstale() 1472 */ 1473 static void 1474 ng_ppp_frag_timeout(node_p node, hook_p hook, void *arg1, int arg2) 1475 { 1476 /* XXX: is this needed? */ 1477 if (NG_NODE_NOT_VALID(node)) 1478 return; 1479 1480 /* Scan the fragment queue */ 1481 ng_ppp_frag_checkstale(node); 1482 1483 /* Start timer again */ 1484 ng_ppp_start_frag_timer(node); 1485 } 1486 1487 /* 1488 * Deliver a frame out on the bundle, i.e., figure out how to fragment 1489 * the frame across the individual PPP links and do so. 1490 */ 1491 static int 1492 ng_ppp_mp_output(node_p node, struct mbuf *m) 1493 { 1494 const priv_p priv = NG_NODE_PRIVATE(node); 1495 const int hdr_len = priv->conf.xmitShortSeq ? 2 : 4; 1496 int distrib[NG_PPP_MAX_LINKS]; 1497 int firstFragment; 1498 int activeLinkNum; 1499 item_p item; 1500 1501 /* At least one link must be active */ 1502 if (priv->numActiveLinks == 0) { 1503 NG_FREE_M(m); 1504 return (ENETDOWN); 1505 } 1506 1507 /* Round-robin strategy */ 1508 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) { 1509 activeLinkNum = priv->lastLink++ % priv->numActiveLinks; 1510 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0])); 1511 distrib[activeLinkNum] = m->m_pkthdr.len; 1512 goto deliver; 1513 } 1514 1515 /* Strategy when all links are equivalent (optimize the common case) */ 1516 if (priv->allLinksEqual) { 1517 const int fraction = m->m_pkthdr.len / priv->numActiveLinks; 1518 int i, remain; 1519 1520 for (i = 0; i < priv->numActiveLinks; i++) 1521 distrib[priv->lastLink++ % priv->numActiveLinks] 1522 = fraction; 1523 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks); 1524 while (remain > 0) { 1525 distrib[priv->lastLink++ % priv->numActiveLinks]++; 1526 remain--; 1527 } 1528 goto deliver; 1529 } 1530 1531 /* Strategy when all links are not equivalent */ 1532 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib); 1533 1534 deliver: 1535 /* Update stats */ 1536 priv->bundleStats.xmitFrames++; 1537 priv->bundleStats.xmitOctets += m->m_pkthdr.len; 1538 1539 /* Send alloted portions of frame out on the link(s) */ 1540 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1; 1541 activeLinkNum >= 0; activeLinkNum--) { 1542 const int linkNum = priv->activeLinks[activeLinkNum]; 1543 struct ng_ppp_link *const link = &priv->links[linkNum]; 1544 1545 /* Deliver fragment(s) out the next link */ 1546 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) { 1547 int len, lastFragment, error; 1548 struct mbuf *m2; 1549 1550 /* Calculate fragment length; don't exceed link MTU */ 1551 len = distrib[activeLinkNum]; 1552 if (len > link->conf.mru - hdr_len) 1553 len = link->conf.mru - hdr_len; 1554 distrib[activeLinkNum] -= len; 1555 lastFragment = (len == m->m_pkthdr.len); 1556 1557 /* Split off next fragment as "m2" */ 1558 m2 = m; 1559 if (!lastFragment) { 1560 struct mbuf *n = m_split(m, len, M_DONTWAIT); 1561 1562 if (n == NULL) { 1563 NG_FREE_M(m); 1564 return (ENOMEM); 1565 } 1566 m = n; 1567 } 1568 1569 /* Prepend MP header */ 1570 if (priv->conf.xmitShortSeq) { 1571 u_int16_t shdr; 1572 1573 shdr = priv->xseq; 1574 priv->xseq = 1575 (priv->xseq + 1) & MP_SHORT_SEQ_MASK; 1576 if (firstFragment) 1577 shdr |= MP_SHORT_FIRST_FLAG; 1578 if (lastFragment) 1579 shdr |= MP_SHORT_LAST_FLAG; 1580 shdr = htons(shdr); 1581 m2 = ng_ppp_prepend(m2, &shdr, 2); 1582 } else { 1583 u_int32_t lhdr; 1584 1585 lhdr = priv->xseq; 1586 priv->xseq = 1587 (priv->xseq + 1) & MP_LONG_SEQ_MASK; 1588 if (firstFragment) 1589 lhdr |= MP_LONG_FIRST_FLAG; 1590 if (lastFragment) 1591 lhdr |= MP_LONG_LAST_FLAG; 1592 lhdr = htonl(lhdr); 1593 m2 = ng_ppp_prepend(m2, &lhdr, 4); 1594 } 1595 if (m2 == NULL) { 1596 if (!lastFragment) 1597 m_freem(m); 1598 return (ENOBUFS); 1599 } 1600 1601 /* Send fragment */ 1602 if ((item = ng_package_data(m2, NG_NOFLAGS)) != NULL) { 1603 error = ng_ppp_output(node, 0, PROT_MP, 1604 linkNum, item); 1605 if (error != 0) { 1606 if (!lastFragment) 1607 NG_FREE_M(m); 1608 return (error); 1609 } 1610 } 1611 } 1612 } 1613 1614 /* Done */ 1615 return (0); 1616 } 1617 1618 /* 1619 * Computing the optimal fragmentation 1620 * ----------------------------------- 1621 * 1622 * This routine tries to compute the optimal fragmentation pattern based 1623 * on each link's latency, bandwidth, and calculated additional latency. 1624 * The latter quantity is the additional latency caused by previously 1625 * written data that has not been transmitted yet. 1626 * 1627 * This algorithm is only useful when not all of the links have the 1628 * same latency and bandwidth values. 1629 * 1630 * The essential idea is to make the last bit of each fragment of the 1631 * frame arrive at the opposite end at the exact same time. This greedy 1632 * algorithm is optimal, in that no other scheduling could result in any 1633 * packet arriving any sooner unless packets are delivered out of order. 1634 * 1635 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and 1636 * latency l_i (in miliseconds). Consider the function function f_i(t) 1637 * which is equal to the number of bytes that will have arrived at 1638 * the peer after t miliseconds if we start writing continuously at 1639 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i). 1640 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i). 1641 * Note that the y-intersect is always <= zero because latency can't be 1642 * negative. Note also that really the function is f_i(t) except when 1643 * f_i(t) is negative, in which case the function is zero. To take 1644 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }. 1645 * So the actual number of bytes that will have arrived at the peer after 1646 * t miliseconds is f_i(t) * Q_i(t). 1647 * 1648 * At any given time, each link has some additional latency a_i >= 0 1649 * due to previously written fragment(s) which are still in the queue. 1650 * This value is easily computed from the time since last transmission, 1651 * the previous latency value, the number of bytes written, and the 1652 * link's bandwidth. 1653 * 1654 * Assume that l_i includes any a_i already, and that the links are 1655 * sorted by latency, so that l_i <= l_{i+1}. 1656 * 1657 * Let N be the total number of bytes in the current frame we are sending. 1658 * 1659 * Suppose we were to start writing bytes at time t = 0 on all links 1660 * simultaneously, which is the most we can possibly do. Then let 1661 * F(t) be equal to the total number of bytes received by the peer 1662 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)). 1663 * 1664 * Our goal is simply this: fragment the frame across the links such 1665 * that the peer is able to reconstruct the completed frame as soon as 1666 * possible, i.e., at the least possible value of t. Call this value t_0. 1667 * 1668 * Then it follows that F(t_0) = N. Our strategy is first to find the value 1669 * of t_0, and then deduce how many bytes to write to each link. 1670 * 1671 * Rewriting F(t_0): 1672 * 1673 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) ) 1674 * 1675 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will 1676 * lie in one of these ranges. To find it, we just need to find the i such 1677 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values 1678 * for Q_i() in this range, plug in the remaining values, solving for t_0. 1679 * 1680 * Once t_0 is known, then the number of bytes to send on link i is 1681 * just f_i(t_0) * Q_i(t_0). 1682 * 1683 * In other words, we start allocating bytes to the links one at a time. 1684 * We keep adding links until the frame is completely sent. Some links 1685 * may not get any bytes because their latency is too high. 1686 * 1687 * Is all this work really worth the trouble? Depends on the situation. 1688 * The bigger the ratio of computer speed to link speed, and the more 1689 * important total bundle latency is (e.g., for interactive response time), 1690 * the more it's worth it. There is however the cost of calling this 1691 * function for every frame. The running time is O(n^2) where n is the 1692 * number of links that receive a non-zero number of bytes. 1693 * 1694 * Since latency is measured in miliseconds, the "resolution" of this 1695 * algorithm is one milisecond. 1696 * 1697 * To avoid this algorithm altogether, configure all links to have the 1698 * same latency and bandwidth. 1699 */ 1700 static void 1701 ng_ppp_mp_strategy(node_p node, int len, int *distrib) 1702 { 1703 const priv_p priv = NG_NODE_PRIVATE(node); 1704 int latency[NG_PPP_MAX_LINKS]; 1705 int sortByLatency[NG_PPP_MAX_LINKS]; 1706 int activeLinkNum; 1707 int t0, total, topSum, botSum; 1708 struct timeval now; 1709 int i, numFragments; 1710 1711 /* If only one link, this gets real easy */ 1712 if (priv->numActiveLinks == 1) { 1713 distrib[0] = len; 1714 return; 1715 } 1716 1717 /* Get current time */ 1718 getmicrouptime(&now); 1719 1720 /* Compute latencies for each link at this point in time */ 1721 for (activeLinkNum = 0; 1722 activeLinkNum < priv->numActiveLinks; activeLinkNum++) { 1723 struct ng_ppp_link *alink; 1724 struct timeval diff; 1725 int xmitBytes; 1726 1727 /* Start with base latency value */ 1728 alink = &priv->links[priv->activeLinks[activeLinkNum]]; 1729 latency[activeLinkNum] = alink->latency; 1730 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */ 1731 1732 /* Any additional latency? */ 1733 if (alink->bytesInQueue == 0) 1734 continue; 1735 1736 /* Compute time delta since last write */ 1737 diff = now; 1738 timevalsub(&diff, &alink->lastWrite); 1739 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */ 1740 alink->bytesInQueue = 0; 1741 continue; 1742 } 1743 1744 /* How many bytes could have transmitted since last write? */ 1745 xmitBytes = (alink->conf.bandwidth * diff.tv_sec) 1746 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100; 1747 alink->bytesInQueue -= xmitBytes; 1748 if (alink->bytesInQueue < 0) 1749 alink->bytesInQueue = 0; 1750 else 1751 latency[activeLinkNum] += 1752 (100 * alink->bytesInQueue) / alink->conf.bandwidth; 1753 } 1754 1755 /* Sort active links by latency */ 1756 qsort_r(sortByLatency, 1757 priv->numActiveLinks, sizeof(*sortByLatency), latency, ng_ppp_intcmp); 1758 1759 /* Find the interval we need (add links in sortByLatency[] order) */ 1760 for (numFragments = 1; 1761 numFragments < priv->numActiveLinks; numFragments++) { 1762 for (total = i = 0; i < numFragments; i++) { 1763 int flowTime; 1764 1765 flowTime = latency[sortByLatency[numFragments]] 1766 - latency[sortByLatency[i]]; 1767 total += ((flowTime * priv->links[ 1768 priv->activeLinks[sortByLatency[i]]].conf.bandwidth) 1769 + 99) / 100; 1770 } 1771 if (total >= len) 1772 break; 1773 } 1774 1775 /* Solve for t_0 in that interval */ 1776 for (topSum = botSum = i = 0; i < numFragments; i++) { 1777 int bw = priv->links[ 1778 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1779 1780 topSum += latency[sortByLatency[i]] * bw; /* / 100 */ 1781 botSum += bw; /* / 100 */ 1782 } 1783 t0 = ((len * 100) + topSum + botSum / 2) / botSum; 1784 1785 /* Compute f_i(t_0) all i */ 1786 bzero(distrib, priv->numActiveLinks * sizeof(*distrib)); 1787 for (total = i = 0; i < numFragments; i++) { 1788 int bw = priv->links[ 1789 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1790 1791 distrib[sortByLatency[i]] = 1792 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100; 1793 total += distrib[sortByLatency[i]]; 1794 } 1795 1796 /* Deal with any rounding error */ 1797 if (total < len) { 1798 struct ng_ppp_link *fastLink = 1799 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1800 int fast = 0; 1801 1802 /* Find the fastest link */ 1803 for (i = 1; i < numFragments; i++) { 1804 struct ng_ppp_link *const link = 1805 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1806 1807 if (link->conf.bandwidth > fastLink->conf.bandwidth) { 1808 fast = i; 1809 fastLink = link; 1810 } 1811 } 1812 distrib[sortByLatency[fast]] += len - total; 1813 } else while (total > len) { 1814 struct ng_ppp_link *slowLink = 1815 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1816 int delta, slow = 0; 1817 1818 /* Find the slowest link that still has bytes to remove */ 1819 for (i = 1; i < numFragments; i++) { 1820 struct ng_ppp_link *const link = 1821 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1822 1823 if (distrib[sortByLatency[slow]] == 0 1824 || (distrib[sortByLatency[i]] > 0 1825 && link->conf.bandwidth < 1826 slowLink->conf.bandwidth)) { 1827 slow = i; 1828 slowLink = link; 1829 } 1830 } 1831 delta = total - len; 1832 if (delta > distrib[sortByLatency[slow]]) 1833 delta = distrib[sortByLatency[slow]]; 1834 distrib[sortByLatency[slow]] -= delta; 1835 total -= delta; 1836 } 1837 } 1838 1839 /* 1840 * Compare two integers 1841 */ 1842 static int 1843 ng_ppp_intcmp(void *latency, const void *v1, const void *v2) 1844 { 1845 const int index1 = *((const int *) v1); 1846 const int index2 = *((const int *) v2); 1847 1848 return ((int *)latency)[index1] - ((int *)latency)[index2]; 1849 } 1850 1851 /* 1852 * Prepend a possibly compressed PPP protocol number in front of a frame 1853 */ 1854 static struct mbuf * 1855 ng_ppp_addproto(struct mbuf *m, int proto, int compOK) 1856 { 1857 if (compOK && PROT_COMPRESSABLE(proto)) { 1858 u_char pbyte = (u_char)proto; 1859 1860 return ng_ppp_prepend(m, &pbyte, 1); 1861 } else { 1862 u_int16_t pword = htons((u_int16_t)proto); 1863 1864 return ng_ppp_prepend(m, &pword, 2); 1865 } 1866 } 1867 1868 /* 1869 * Prepend some bytes to an mbuf 1870 */ 1871 static struct mbuf * 1872 ng_ppp_prepend(struct mbuf *m, const void *buf, int len) 1873 { 1874 M_PREPEND(m, len, M_DONTWAIT); 1875 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL)) 1876 return (NULL); 1877 bcopy(buf, mtod(m, u_char *), len); 1878 return (m); 1879 } 1880 1881 /* 1882 * Update private information that is derived from other private information 1883 */ 1884 static void 1885 ng_ppp_update(node_p node, int newConf) 1886 { 1887 const priv_p priv = NG_NODE_PRIVATE(node); 1888 int i; 1889 1890 /* Update active status for VJ Compression */ 1891 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL 1892 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL 1893 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL 1894 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL; 1895 1896 /* Increase latency for each link an amount equal to one MP header */ 1897 if (newConf) { 1898 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1899 int hdrBytes; 1900 1901 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2) 1902 + (priv->links[i].conf.enableProtoComp ? 1 : 2) 1903 + (priv->conf.xmitShortSeq ? 2 : 4); 1904 priv->links[i].latency = 1905 priv->links[i].conf.latency + 1906 ((hdrBytes * priv->links[i].conf.bandwidth) + 50) 1907 / 100; 1908 } 1909 } 1910 1911 /* Update list of active links */ 1912 bzero(&priv->activeLinks, sizeof(priv->activeLinks)); 1913 priv->numActiveLinks = 0; 1914 priv->allLinksEqual = 1; 1915 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1916 struct ng_ppp_link *const link = &priv->links[i]; 1917 1918 /* Is link active? */ 1919 if (link->conf.enableLink && link->hook != NULL) { 1920 struct ng_ppp_link *link0; 1921 1922 /* Add link to list of active links */ 1923 priv->activeLinks[priv->numActiveLinks++] = i; 1924 link0 = &priv->links[priv->activeLinks[0]]; 1925 1926 /* Determine if all links are still equal */ 1927 if (link->latency != link0->latency 1928 || link->conf.bandwidth != link0->conf.bandwidth) 1929 priv->allLinksEqual = 0; 1930 1931 /* Initialize rec'd sequence number */ 1932 if (link->seq == MP_NOSEQ) { 1933 link->seq = (link == link0) ? 1934 MP_INITIAL_SEQ : link0->seq; 1935 } 1936 } else 1937 link->seq = MP_NOSEQ; 1938 } 1939 1940 /* Update MP state as multi-link is active or not */ 1941 if (priv->conf.enableMultilink && priv->numActiveLinks > 0) 1942 ng_ppp_start_frag_timer(node); 1943 else { 1944 ng_ppp_stop_frag_timer(node); 1945 ng_ppp_frag_reset(node); 1946 priv->xseq = MP_INITIAL_SEQ; 1947 priv->mseq = MP_INITIAL_SEQ; 1948 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1949 struct ng_ppp_link *const link = &priv->links[i]; 1950 1951 bzero(&link->lastWrite, sizeof(link->lastWrite)); 1952 link->bytesInQueue = 0; 1953 link->seq = MP_NOSEQ; 1954 } 1955 } 1956 } 1957 1958 /* 1959 * Determine if a new configuration would represent a valid change 1960 * from the current configuration and link activity status. 1961 */ 1962 static int 1963 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf) 1964 { 1965 const priv_p priv = NG_NODE_PRIVATE(node); 1966 int i, newNumLinksActive; 1967 1968 /* Check per-link config and count how many links would be active */ 1969 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) { 1970 if (newConf->links[i].enableLink && priv->links[i].hook != NULL) 1971 newNumLinksActive++; 1972 if (!newConf->links[i].enableLink) 1973 continue; 1974 if (newConf->links[i].mru < MP_MIN_LINK_MRU) 1975 return (0); 1976 if (newConf->links[i].bandwidth == 0) 1977 return (0); 1978 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH) 1979 return (0); 1980 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY) 1981 return (0); 1982 } 1983 1984 /* Check bundle parameters */ 1985 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU) 1986 return (0); 1987 1988 /* Disallow changes to multi-link configuration while MP is active */ 1989 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) { 1990 if (!priv->conf.enableMultilink 1991 != !newConf->bund.enableMultilink 1992 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq 1993 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq) 1994 return (0); 1995 } 1996 1997 /* At most one link can be active unless multi-link is enabled */ 1998 if (!newConf->bund.enableMultilink && newNumLinksActive > 1) 1999 return (0); 2000 2001 /* Configuration change would be valid */ 2002 return (1); 2003 } 2004 2005 /* 2006 * Free all entries in the fragment queue 2007 */ 2008 static void 2009 ng_ppp_frag_reset(node_p node) 2010 { 2011 const priv_p priv = NG_NODE_PRIVATE(node); 2012 struct ng_ppp_frag *qent, *qnext; 2013 2014 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) { 2015 qnext = TAILQ_NEXT(qent, f_qent); 2016 NG_FREE_M(qent->data); 2017 FREE(qent, M_NETGRAPH_PPP); 2018 } 2019 TAILQ_INIT(&priv->frags); 2020 priv->qlen = 0; 2021 } 2022 2023 /* 2024 * Start fragment queue timer 2025 */ 2026 static void 2027 ng_ppp_start_frag_timer(node_p node) 2028 { 2029 const priv_p priv = NG_NODE_PRIVATE(node); 2030 2031 if (!(callout_pending(&priv->fragTimer))) 2032 ng_callout(&priv->fragTimer, node, NULL, MP_FRAGTIMER_INTERVAL, 2033 ng_ppp_frag_timeout, NULL, 0); 2034 } 2035 2036 /* 2037 * Stop fragment queue timer 2038 */ 2039 static void 2040 ng_ppp_stop_frag_timer(node_p node) 2041 { 2042 const priv_p priv = NG_NODE_PRIVATE(node); 2043 2044 if (callout_pending(&priv->fragTimer)) 2045 ng_uncallout(&priv->fragTimer, node); 2046 } 2047