1 2 /* 3 * ng_ppp.c 4 * 5 * Copyright (c) 1996-2000 Whistle Communications, Inc. 6 * All rights reserved. 7 * 8 * Subject to the following obligations and disclaimer of warranty, use and 9 * redistribution of this software, in source or object code forms, with or 10 * without modifications are expressly permitted by Whistle Communications; 11 * provided, however, that: 12 * 1. Any and all reproductions of the source or object code must include the 13 * copyright notice above and the following disclaimer of warranties; and 14 * 2. No rights are granted, in any manner or form, to use Whistle 15 * Communications, Inc. trademarks, including the mark "WHISTLE 16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 17 * such appears in the above copyright notice or in the software. 18 * 19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 35 * OF SUCH DAMAGE. 36 * 37 * Author: Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $ 41 */ 42 43 /* 44 * PPP node type. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/time.h> 51 #include <sys/mbuf.h> 52 #include <sys/malloc.h> 53 #include <sys/errno.h> 54 #include <sys/ctype.h> 55 56 #include <machine/limits.h> 57 58 #include <netgraph/ng_message.h> 59 #include <netgraph/netgraph.h> 60 #include <netgraph/ng_parse.h> 61 #include <netgraph/ng_ppp.h> 62 #include <netgraph/ng_vjc.h> 63 64 #define PROT_VALID(p) (((p) & 0x0101) == 0x0001) 65 #define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000) 66 67 /* Some PPP protocol numbers we're interested in */ 68 #define PROT_APPLETALK 0x0029 69 #define PROT_COMPD 0x00fd 70 #define PROT_CRYPTD 0x0053 71 #define PROT_IP 0x0021 72 #define PROT_IPV6 0x0057 73 #define PROT_IPX 0x002b 74 #define PROT_LCP 0xc021 75 #define PROT_MP 0x003d 76 #define PROT_VJCOMP 0x002d 77 #define PROT_VJUNCOMP 0x002f 78 79 /* Multilink PPP definitions */ 80 #define MP_MIN_MRRU 1500 /* per RFC 1990 */ 81 #define MP_INITIAL_SEQ 0 /* per RFC 1990 */ 82 #define MP_MIN_LINK_MRU 32 83 84 #define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */ 85 #define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */ 86 #define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */ 87 #define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */ 88 89 #define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */ 90 #define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */ 91 #define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */ 92 #define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */ 93 94 #define MP_NOSEQ 0x7fffffff /* impossible sequence number */ 95 96 /* Sign extension of MP sequence numbers */ 97 #define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \ 98 ((s) | ~MP_SHORT_SEQ_MASK) \ 99 : ((s) & MP_SHORT_SEQ_MASK)) 100 #define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \ 101 ((s) | ~MP_LONG_SEQ_MASK) \ 102 : ((s) & MP_LONG_SEQ_MASK)) 103 104 /* Comparision of MP sequence numbers. Note: all sequence numbers 105 except priv->xseq are stored with the sign bit extended. */ 106 #define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y)) 107 #define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y)) 108 109 #define MP_RECV_SEQ_DIFF(priv,x,y) \ 110 ((priv)->conf.recvShortSeq ? \ 111 MP_SHORT_SEQ_DIFF((x), (y)) : \ 112 MP_LONG_SEQ_DIFF((x), (y))) 113 114 /* Increment receive sequence number */ 115 #define MP_NEXT_RECV_SEQ(priv,seq) \ 116 (((seq) + 1) & ((priv)->conf.recvShortSeq ? \ 117 MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK)) 118 119 /* Don't fragment transmitted packets smaller than this */ 120 #define MP_MIN_FRAG_LEN 6 121 122 /* Maximum fragment reasssembly queue length */ 123 #define MP_MAX_QUEUE_LEN 128 124 125 /* Fragment queue scanner period */ 126 #define MP_FRAGTIMER_INTERVAL (hz/2) 127 128 /* We store incoming fragments this way */ 129 struct ng_ppp_frag { 130 int seq; /* fragment seq# */ 131 u_char first; /* First in packet? */ 132 u_char last; /* Last in packet? */ 133 struct timeval timestamp; /* time of reception */ 134 struct mbuf *data; /* Fragment data */ 135 meta_p meta; /* Fragment meta */ 136 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */ 137 }; 138 139 /* We use integer indicies to refer to the non-link hooks */ 140 static const char *const ng_ppp_hook_names[] = { 141 NG_PPP_HOOK_ATALK, 142 #define HOOK_INDEX_ATALK 0 143 NG_PPP_HOOK_BYPASS, 144 #define HOOK_INDEX_BYPASS 1 145 NG_PPP_HOOK_COMPRESS, 146 #define HOOK_INDEX_COMPRESS 2 147 NG_PPP_HOOK_ENCRYPT, 148 #define HOOK_INDEX_ENCRYPT 3 149 NG_PPP_HOOK_DECOMPRESS, 150 #define HOOK_INDEX_DECOMPRESS 4 151 NG_PPP_HOOK_DECRYPT, 152 #define HOOK_INDEX_DECRYPT 5 153 NG_PPP_HOOK_INET, 154 #define HOOK_INDEX_INET 6 155 NG_PPP_HOOK_IPX, 156 #define HOOK_INDEX_IPX 7 157 NG_PPP_HOOK_VJC_COMP, 158 #define HOOK_INDEX_VJC_COMP 8 159 NG_PPP_HOOK_VJC_IP, 160 #define HOOK_INDEX_VJC_IP 9 161 NG_PPP_HOOK_VJC_UNCOMP, 162 #define HOOK_INDEX_VJC_UNCOMP 10 163 NG_PPP_HOOK_VJC_VJIP, 164 #define HOOK_INDEX_VJC_VJIP 11 165 NG_PPP_HOOK_IPV6, 166 #define HOOK_INDEX_IPV6 12 167 NULL 168 #define HOOK_INDEX_MAX 13 169 }; 170 171 /* We store index numbers in the hook private pointer. The HOOK_INDEX() 172 for a hook is either the index (above) for normal hooks, or the ones 173 complement of the link number for link hooks. */ 174 #define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private)) 175 176 /* Per-link private information */ 177 struct ng_ppp_link { 178 struct ng_ppp_link_conf conf; /* link configuration */ 179 hook_p hook; /* connection to link data */ 180 int32_t seq; /* highest rec'd seq# - MSEQ */ 181 struct timeval lastWrite; /* time of last write */ 182 int bytesInQueue; /* bytes in the output queue */ 183 struct ng_ppp_link_stat stats; /* Link stats */ 184 }; 185 186 /* Total per-node private information */ 187 struct ng_ppp_private { 188 struct ng_ppp_bund_conf conf; /* bundle config */ 189 struct ng_ppp_link_stat bundleStats; /* bundle stats */ 190 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */ 191 int32_t xseq; /* next out MP seq # */ 192 int32_t mseq; /* min links[i].seq */ 193 u_char vjCompHooked; /* VJ comp hooked up? */ 194 u_char allLinksEqual; /* all xmit the same? */ 195 u_char timerActive; /* frag timer active? */ 196 u_int numActiveLinks; /* how many links up */ 197 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */ 198 u_int lastLink; /* for round robin */ 199 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */ 200 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */ 201 frags; 202 int qlen; /* fraq queue length */ 203 struct callout_handle fragTimer; /* fraq queue check */ 204 }; 205 typedef struct ng_ppp_private *priv_p; 206 207 /* Netgraph node methods */ 208 static ng_constructor_t ng_ppp_constructor; 209 static ng_rcvmsg_t ng_ppp_rcvmsg; 210 static ng_shutdown_t ng_ppp_rmnode; 211 static ng_newhook_t ng_ppp_newhook; 212 static ng_rcvdata_t ng_ppp_rcvdata; 213 static ng_disconnect_t ng_ppp_disconnect; 214 215 /* Helper functions */ 216 static int ng_ppp_input(node_p node, int bypass, 217 int linkNum, struct mbuf *m, meta_p meta); 218 static int ng_ppp_output(node_p node, int bypass, int proto, 219 int linkNum, struct mbuf *m, meta_p meta); 220 static int ng_ppp_mp_input(node_p node, int linkNum, 221 struct mbuf *m, meta_p meta); 222 static int ng_ppp_check_packet(node_p node); 223 static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap); 224 static int ng_ppp_frag_process(node_p node); 225 static int ng_ppp_frag_trim(node_p node); 226 static void ng_ppp_frag_timeout(void *arg); 227 static void ng_ppp_frag_checkstale(node_p node); 228 static void ng_ppp_frag_reset(node_p node); 229 static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta); 230 static void ng_ppp_mp_strategy(node_p node, int len, int *distrib); 231 static int ng_ppp_intcmp(const void *v1, const void *v2); 232 static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK); 233 static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len); 234 static int ng_ppp_config_valid(node_p node, 235 const struct ng_ppp_node_conf *newConf); 236 static void ng_ppp_update(node_p node, int newConf); 237 static void ng_ppp_start_frag_timer(node_p node); 238 static void ng_ppp_stop_frag_timer(node_p node); 239 240 /* Parse type for struct ng_ppp_mp_state_type */ 241 static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = { 242 &ng_parse_hint32_type, 243 NG_PPP_MAX_LINKS 244 }; 245 static const struct ng_parse_type ng_ppp_rseq_array_type = { 246 &ng_parse_fixedarray_type, 247 &ng_ppp_rseq_array_info, 248 }; 249 static const struct ng_parse_struct_info ng_ppp_mp_state_type_info 250 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type); 251 static const struct ng_parse_type ng_ppp_mp_state_type = { 252 &ng_parse_struct_type, 253 &ng_ppp_mp_state_type_info, 254 }; 255 256 /* Parse type for struct ng_ppp_link_conf */ 257 static const struct ng_parse_struct_info 258 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO; 259 static const struct ng_parse_type ng_ppp_link_type = { 260 &ng_parse_struct_type, 261 &ng_ppp_link_type_info, 262 }; 263 264 /* Parse type for struct ng_ppp_bund_conf */ 265 static const struct ng_parse_struct_info 266 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO; 267 static const struct ng_parse_type ng_ppp_bund_type = { 268 &ng_parse_struct_type, 269 &ng_ppp_bund_type_info, 270 }; 271 272 /* Parse type for struct ng_ppp_node_conf */ 273 static const struct ng_parse_fixedarray_info ng_ppp_array_info = { 274 &ng_ppp_link_type, 275 NG_PPP_MAX_LINKS 276 }; 277 static const struct ng_parse_type ng_ppp_link_array_type = { 278 &ng_parse_fixedarray_type, 279 &ng_ppp_array_info, 280 }; 281 static const struct ng_parse_struct_info ng_ppp_conf_type_info 282 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type); 283 static const struct ng_parse_type ng_ppp_conf_type = { 284 &ng_parse_struct_type, 285 &ng_ppp_conf_type_info 286 }; 287 288 /* Parse type for struct ng_ppp_link_stat */ 289 static const struct ng_parse_struct_info 290 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO; 291 static const struct ng_parse_type ng_ppp_stats_type = { 292 &ng_parse_struct_type, 293 &ng_ppp_stats_type_info 294 }; 295 296 /* List of commands and how to convert arguments to/from ASCII */ 297 static const struct ng_cmdlist ng_ppp_cmds[] = { 298 { 299 NGM_PPP_COOKIE, 300 NGM_PPP_SET_CONFIG, 301 "setconfig", 302 &ng_ppp_conf_type, 303 NULL 304 }, 305 { 306 NGM_PPP_COOKIE, 307 NGM_PPP_GET_CONFIG, 308 "getconfig", 309 NULL, 310 &ng_ppp_conf_type 311 }, 312 { 313 NGM_PPP_COOKIE, 314 NGM_PPP_GET_MP_STATE, 315 "getmpstate", 316 NULL, 317 &ng_ppp_mp_state_type 318 }, 319 { 320 NGM_PPP_COOKIE, 321 NGM_PPP_GET_LINK_STATS, 322 "getstats", 323 &ng_parse_int16_type, 324 &ng_ppp_stats_type 325 }, 326 { 327 NGM_PPP_COOKIE, 328 NGM_PPP_CLR_LINK_STATS, 329 "clrstats", 330 &ng_parse_int16_type, 331 NULL 332 }, 333 { 334 NGM_PPP_COOKIE, 335 NGM_PPP_GETCLR_LINK_STATS, 336 "getclrstats", 337 &ng_parse_int16_type, 338 &ng_ppp_stats_type 339 }, 340 { 0 } 341 }; 342 343 /* Node type descriptor */ 344 static struct ng_type ng_ppp_typestruct = { 345 NG_VERSION, 346 NG_PPP_NODE_TYPE, 347 NULL, 348 ng_ppp_constructor, 349 ng_ppp_rcvmsg, 350 ng_ppp_rmnode, 351 ng_ppp_newhook, 352 NULL, 353 NULL, 354 ng_ppp_rcvdata, 355 ng_ppp_rcvdata, 356 ng_ppp_disconnect, 357 ng_ppp_cmds 358 }; 359 NETGRAPH_INIT(ppp, &ng_ppp_typestruct); 360 361 static int *compareLatencies; /* hack for ng_ppp_intcmp() */ 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 *nodep) 380 { 381 priv_p priv; 382 int i, error; 383 384 /* Allocate private structure */ 385 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 386 if (priv == NULL) 387 return (ENOMEM); 388 389 /* Call generic node constructor */ 390 if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) { 391 FREE(priv, M_NETGRAPH); 392 return (error); 393 } 394 (*nodep)->private = priv; 395 396 /* Initialize state */ 397 TAILQ_INIT(&priv->frags); 398 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 399 priv->links[i].seq = MP_NOSEQ; 400 callout_handle_init(&priv->fragTimer); 401 402 /* Done */ 403 return (0); 404 } 405 406 /* 407 * Give our OK for a hook to be added 408 */ 409 static int 410 ng_ppp_newhook(node_p node, hook_p hook, const char *name) 411 { 412 const priv_p priv = node->private; 413 int linkNum = -1; 414 hook_p *hookPtr = NULL; 415 int hookIndex = -1; 416 417 /* Figure out which hook it is */ 418 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */ 419 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) { 420 const char *cp; 421 char *eptr; 422 423 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX); 424 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 425 return (EINVAL); 426 linkNum = (int)strtoul(cp, &eptr, 10); 427 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS) 428 return (EINVAL); 429 hookPtr = &priv->links[linkNum].hook; 430 hookIndex = ~linkNum; 431 } else { /* must be a non-link hook */ 432 int i; 433 434 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) { 435 if (strcmp(name, ng_ppp_hook_names[i]) == 0) { 436 hookPtr = &priv->hooks[i]; 437 hookIndex = i; 438 break; 439 } 440 } 441 if (ng_ppp_hook_names[i] == NULL) 442 return (EINVAL); /* no such hook */ 443 } 444 445 /* See if hook is already connected */ 446 if (*hookPtr != NULL) 447 return (EISCONN); 448 449 /* Disallow more than one link unless multilink is enabled */ 450 if (linkNum != -1 && priv->links[linkNum].conf.enableLink 451 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1) 452 return (ENODEV); 453 454 /* OK */ 455 *hookPtr = hook; 456 HOOK_INDEX(hook) = hookIndex; 457 ng_ppp_update(node, 0); 458 return (0); 459 } 460 461 /* 462 * Receive a control message 463 */ 464 static int 465 ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg, 466 const char *raddr, struct ng_mesg **rptr, hook_p lasthook) 467 { 468 const priv_p priv = node->private; 469 struct ng_mesg *resp = NULL; 470 int error = 0; 471 472 switch (msg->header.typecookie) { 473 case NGM_PPP_COOKIE: 474 switch (msg->header.cmd) { 475 case NGM_PPP_SET_CONFIG: 476 { 477 struct ng_ppp_node_conf *const conf = 478 (struct ng_ppp_node_conf *)msg->data; 479 int i; 480 481 /* Check for invalid or illegal config */ 482 if (msg->header.arglen != sizeof(*conf)) 483 ERROUT(EINVAL); 484 if (!ng_ppp_config_valid(node, conf)) 485 ERROUT(EINVAL); 486 487 /* Copy config */ 488 priv->conf = conf->bund; 489 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 490 priv->links[i].conf = conf->links[i]; 491 ng_ppp_update(node, 1); 492 break; 493 } 494 case NGM_PPP_GET_CONFIG: 495 { 496 struct ng_ppp_node_conf *conf; 497 int i; 498 499 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT); 500 if (resp == NULL) 501 ERROUT(ENOMEM); 502 conf = (struct ng_ppp_node_conf *)resp->data; 503 conf->bund = priv->conf; 504 for (i = 0; i < NG_PPP_MAX_LINKS; i++) 505 conf->links[i] = priv->links[i].conf; 506 break; 507 } 508 case NGM_PPP_GET_MP_STATE: 509 { 510 struct ng_ppp_mp_state *info; 511 int i; 512 513 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT); 514 if (resp == NULL) 515 ERROUT(ENOMEM); 516 info = (struct ng_ppp_mp_state *)resp->data; 517 bzero(info, sizeof(*info)); 518 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 519 if (priv->links[i].seq != MP_NOSEQ) 520 info->rseq[i] = priv->links[i].seq; 521 } 522 info->mseq = priv->mseq; 523 info->xseq = priv->xseq; 524 break; 525 } 526 case NGM_PPP_GET_LINK_STATS: 527 case NGM_PPP_CLR_LINK_STATS: 528 case NGM_PPP_GETCLR_LINK_STATS: 529 { 530 struct ng_ppp_link_stat *stats; 531 u_int16_t linkNum; 532 533 if (msg->header.arglen != sizeof(u_int16_t)) 534 ERROUT(EINVAL); 535 linkNum = *((u_int16_t *) msg->data); 536 if (linkNum >= NG_PPP_MAX_LINKS 537 && linkNum != NG_PPP_BUNDLE_LINKNUM) 538 ERROUT(EINVAL); 539 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ? 540 &priv->bundleStats : &priv->links[linkNum].stats; 541 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) { 542 NG_MKRESPONSE(resp, msg, 543 sizeof(struct ng_ppp_link_stat), M_NOWAIT); 544 if (resp == NULL) 545 ERROUT(ENOMEM); 546 bcopy(stats, resp->data, sizeof(*stats)); 547 } 548 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS) 549 bzero(stats, sizeof(*stats)); 550 break; 551 } 552 default: 553 error = EINVAL; 554 break; 555 } 556 break; 557 case NGM_VJC_COOKIE: 558 { 559 char path[NG_PATHLEN + 1]; 560 node_p origNode; 561 562 if ((error = ng_path2node(node, 563 raddr, &origNode, NULL, NULL)) != 0) 564 ERROUT(error); 565 snprintf(path, sizeof(path), "[%lx]:%s", 566 (long)node, NG_PPP_HOOK_VJC_IP); 567 return ng_send_msg(origNode, msg, path, rptr); 568 } 569 default: 570 error = EINVAL; 571 break; 572 } 573 if (rptr) 574 *rptr = resp; 575 else if (resp) 576 FREE(resp, M_NETGRAPH); 577 578 done: 579 FREE(msg, M_NETGRAPH); 580 return (error); 581 } 582 583 /* 584 * Receive data on a hook 585 */ 586 static int 587 ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta, 588 struct mbuf **ret_m, meta_p *ret_meta) 589 { 590 const node_p node = hook->node; 591 const priv_p priv = node->private; 592 const int index = HOOK_INDEX(hook); 593 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM; 594 hook_p outHook = NULL; 595 int proto = 0, error; 596 597 /* Did it come from a link hook? */ 598 if (index < 0) { 599 struct ng_ppp_link *link; 600 601 /* Convert index into a link number */ 602 linkNum = (u_int16_t)~index; 603 KASSERT(linkNum < NG_PPP_MAX_LINKS, 604 ("%s: bogus index 0x%x", __FUNCTION__, index)); 605 link = &priv->links[linkNum]; 606 607 /* Stats */ 608 link->stats.recvFrames++; 609 link->stats.recvOctets += m->m_pkthdr.len; 610 611 /* Strip address and control fields, if present */ 612 if (m->m_pkthdr.len >= 2) { 613 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 614 NG_FREE_DATA(m, meta); 615 return (ENOBUFS); 616 } 617 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0) 618 m_adj(m, 2); 619 } 620 621 /* Dispatch incoming frame (if not enabled, to bypass) */ 622 return ng_ppp_input(node, 623 !link->conf.enableLink, linkNum, m, meta); 624 } 625 626 /* Get protocol & check if data allowed from this hook */ 627 switch (index) { 628 629 /* Outgoing data */ 630 case HOOK_INDEX_ATALK: 631 if (!priv->conf.enableAtalk) { 632 NG_FREE_DATA(m, meta); 633 return (ENXIO); 634 } 635 proto = PROT_APPLETALK; 636 break; 637 case HOOK_INDEX_IPX: 638 if (!priv->conf.enableIPX) { 639 NG_FREE_DATA(m, meta); 640 return (ENXIO); 641 } 642 proto = PROT_IPX; 643 break; 644 case HOOK_INDEX_IPV6: 645 if (!priv->conf.enableIPv6) { 646 NG_FREE_DATA(m, meta); 647 return (ENXIO); 648 } 649 proto = PROT_IPV6; 650 break; 651 case HOOK_INDEX_INET: 652 case HOOK_INDEX_VJC_VJIP: 653 if (!priv->conf.enableIP) { 654 NG_FREE_DATA(m, meta); 655 return (ENXIO); 656 } 657 proto = PROT_IP; 658 break; 659 case HOOK_INDEX_VJC_COMP: 660 if (!priv->conf.enableVJCompression) { 661 NG_FREE_DATA(m, meta); 662 return (ENXIO); 663 } 664 proto = PROT_VJCOMP; 665 break; 666 case HOOK_INDEX_VJC_UNCOMP: 667 if (!priv->conf.enableVJCompression) { 668 NG_FREE_DATA(m, meta); 669 return (ENXIO); 670 } 671 proto = PROT_VJUNCOMP; 672 break; 673 case HOOK_INDEX_COMPRESS: 674 if (!priv->conf.enableCompression) { 675 NG_FREE_DATA(m, meta); 676 return (ENXIO); 677 } 678 proto = PROT_COMPD; 679 break; 680 case HOOK_INDEX_ENCRYPT: 681 if (!priv->conf.enableEncryption) { 682 NG_FREE_DATA(m, meta); 683 return (ENXIO); 684 } 685 proto = PROT_CRYPTD; 686 break; 687 case HOOK_INDEX_BYPASS: 688 if (m->m_pkthdr.len < 4) { 689 NG_FREE_DATA(m, meta); 690 return (EINVAL); 691 } 692 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 693 NG_FREE_META(meta); 694 return (ENOBUFS); 695 } 696 linkNum = ntohs(mtod(m, u_int16_t *)[0]); 697 proto = ntohs(mtod(m, u_int16_t *)[1]); 698 m_adj(m, 4); 699 if (linkNum >= NG_PPP_MAX_LINKS 700 && linkNum != NG_PPP_BUNDLE_LINKNUM) { 701 NG_FREE_DATA(m, meta); 702 return (EINVAL); 703 } 704 break; 705 706 /* Incoming data */ 707 case HOOK_INDEX_VJC_IP: 708 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) { 709 NG_FREE_DATA(m, meta); 710 return (ENXIO); 711 } 712 break; 713 case HOOK_INDEX_DECOMPRESS: 714 if (!priv->conf.enableDecompression) { 715 NG_FREE_DATA(m, meta); 716 return (ENXIO); 717 } 718 break; 719 case HOOK_INDEX_DECRYPT: 720 if (!priv->conf.enableDecryption) { 721 NG_FREE_DATA(m, meta); 722 return (ENXIO); 723 } 724 break; 725 default: 726 panic("%s: bogus index 0x%x", __FUNCTION__, index); 727 } 728 729 /* Now figure out what to do with the frame */ 730 switch (index) { 731 732 /* Outgoing data */ 733 case HOOK_INDEX_INET: 734 if (priv->conf.enableVJCompression && priv->vjCompHooked) { 735 outHook = priv->hooks[HOOK_INDEX_VJC_IP]; 736 break; 737 } 738 /* FALLTHROUGH */ 739 case HOOK_INDEX_ATALK: 740 case HOOK_INDEX_IPV6: 741 case HOOK_INDEX_IPX: 742 case HOOK_INDEX_VJC_COMP: 743 case HOOK_INDEX_VJC_UNCOMP: 744 case HOOK_INDEX_VJC_VJIP: 745 if (priv->conf.enableCompression 746 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) { 747 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 748 NG_FREE_META(meta); 749 return (ENOBUFS); 750 } 751 outHook = priv->hooks[HOOK_INDEX_COMPRESS]; 752 break; 753 } 754 /* FALLTHROUGH */ 755 case HOOK_INDEX_COMPRESS: 756 if (priv->conf.enableEncryption 757 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) { 758 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) { 759 NG_FREE_META(meta); 760 return (ENOBUFS); 761 } 762 outHook = priv->hooks[HOOK_INDEX_ENCRYPT]; 763 break; 764 } 765 /* FALLTHROUGH */ 766 case HOOK_INDEX_ENCRYPT: 767 return ng_ppp_output(node, 0, 768 proto, NG_PPP_BUNDLE_LINKNUM, m, meta); 769 770 case HOOK_INDEX_BYPASS: 771 return ng_ppp_output(node, 1, proto, linkNum, m, meta); 772 773 /* Incoming data */ 774 case HOOK_INDEX_DECRYPT: 775 case HOOK_INDEX_DECOMPRESS: 776 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta); 777 778 case HOOK_INDEX_VJC_IP: 779 outHook = priv->hooks[HOOK_INDEX_INET]; 780 break; 781 } 782 783 /* Send packet out hook */ 784 NG_SEND_DATA_RET(error, outHook, m, meta); 785 if (m != NULL || meta != NULL) 786 return ng_ppp_rcvdata(outHook, m, meta, NULL, NULL); 787 return (error); 788 } 789 790 /* 791 * Destroy node 792 */ 793 static int 794 ng_ppp_rmnode(node_p node) 795 { 796 const priv_p priv = node->private; 797 798 /* Stop fragment queue timer */ 799 ng_ppp_stop_frag_timer(node); 800 801 /* Take down netgraph node */ 802 node->flags |= NG_INVALID; 803 ng_cutlinks(node); 804 ng_unname(node); 805 ng_ppp_frag_reset(node); 806 bzero(priv, sizeof(*priv)); 807 FREE(priv, M_NETGRAPH); 808 node->private = NULL; 809 ng_unref(node); /* let the node escape */ 810 return (0); 811 } 812 813 /* 814 * Hook disconnection 815 */ 816 static int 817 ng_ppp_disconnect(hook_p hook) 818 { 819 const node_p node = hook->node; 820 const priv_p priv = node->private; 821 const int index = HOOK_INDEX(hook); 822 823 /* Zero out hook pointer */ 824 if (index < 0) 825 priv->links[~index].hook = NULL; 826 else 827 priv->hooks[index] = NULL; 828 829 /* Update derived info (or go away if no hooks left) */ 830 if (node->numhooks > 0) 831 ng_ppp_update(node, 0); 832 else 833 ng_rmnode(node); 834 return (0); 835 } 836 837 /************************************************************************ 838 HELPER STUFF 839 ************************************************************************/ 840 841 /* 842 * Handle an incoming frame. Extract the PPP protocol number 843 * and dispatch accordingly. 844 */ 845 static int 846 ng_ppp_input(node_p node, int bypass, int linkNum, struct mbuf *m, meta_p meta) 847 { 848 const priv_p priv = node->private; 849 hook_p outHook = NULL; 850 int proto, error; 851 852 /* Extract protocol number */ 853 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) { 854 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) { 855 NG_FREE_META(meta); 856 return (ENOBUFS); 857 } 858 proto = (proto << 8) + *mtod(m, u_char *); 859 m_adj(m, 1); 860 } 861 if (!PROT_VALID(proto)) { 862 if (linkNum == NG_PPP_BUNDLE_LINKNUM) 863 priv->bundleStats.badProtos++; 864 else 865 priv->links[linkNum].stats.badProtos++; 866 NG_FREE_DATA(m, meta); 867 return (EINVAL); 868 } 869 870 /* Bypass frame? */ 871 if (bypass) 872 goto bypass; 873 874 /* Check protocol */ 875 switch (proto) { 876 case PROT_COMPD: 877 if (priv->conf.enableDecompression) 878 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS]; 879 break; 880 case PROT_CRYPTD: 881 if (priv->conf.enableDecryption) 882 outHook = priv->hooks[HOOK_INDEX_DECRYPT]; 883 break; 884 case PROT_VJCOMP: 885 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 886 outHook = priv->hooks[HOOK_INDEX_VJC_COMP]; 887 break; 888 case PROT_VJUNCOMP: 889 if (priv->conf.enableVJDecompression && priv->vjCompHooked) 890 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP]; 891 break; 892 case PROT_MP: 893 if (priv->conf.enableMultilink 894 && linkNum != NG_PPP_BUNDLE_LINKNUM) 895 return ng_ppp_mp_input(node, linkNum, m, meta); 896 break; 897 case PROT_APPLETALK: 898 if (priv->conf.enableAtalk) 899 outHook = priv->hooks[HOOK_INDEX_ATALK]; 900 break; 901 case PROT_IPX: 902 if (priv->conf.enableIPX) 903 outHook = priv->hooks[HOOK_INDEX_IPX]; 904 break; 905 case PROT_IP: 906 if (priv->conf.enableIP) 907 outHook = priv->hooks[HOOK_INDEX_INET]; 908 break; 909 case PROT_IPV6: 910 if (priv->conf.enableIPv6) 911 outHook = priv->hooks[HOOK_INDEX_IPV6]; 912 break; 913 } 914 915 bypass: 916 /* For unknown/inactive protocols, forward out the bypass hook */ 917 if (outHook == NULL) { 918 u_int16_t hdr[2]; 919 920 hdr[0] = htons(linkNum); 921 hdr[1] = htons((u_int16_t)proto); 922 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) { 923 NG_FREE_META(meta); 924 return (ENOBUFS); 925 } 926 outHook = priv->hooks[HOOK_INDEX_BYPASS]; 927 } 928 929 /* Forward frame */ 930 NG_SEND_DATA(error, outHook, m, meta); 931 return (error); 932 } 933 934 /* 935 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM 936 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0. 937 */ 938 static int 939 ng_ppp_output(node_p node, int bypass, 940 int proto, int linkNum, struct mbuf *m, meta_p meta) 941 { 942 const priv_p priv = node->private; 943 struct ng_ppp_link *link; 944 int len, error; 945 946 /* If not doing MP, map bundle virtual link to (the only) link */ 947 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink) 948 linkNum = priv->activeLinks[0]; 949 950 /* Get link pointer (optimization) */ 951 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ? 952 &priv->links[linkNum] : NULL; 953 954 /* Check link status (if real) */ 955 if (linkNum != NG_PPP_BUNDLE_LINKNUM) { 956 if (!bypass && !link->conf.enableLink) { 957 NG_FREE_DATA(m, meta); 958 return (ENXIO); 959 } 960 if (link->hook == NULL) { 961 NG_FREE_DATA(m, meta); 962 return (ENETDOWN); 963 } 964 } 965 966 /* Prepend protocol number, possibly compressed */ 967 if ((m = ng_ppp_addproto(m, proto, 968 linkNum == NG_PPP_BUNDLE_LINKNUM 969 || link->conf.enableProtoComp)) == NULL) { 970 NG_FREE_META(meta); 971 return (ENOBUFS); 972 } 973 974 /* Special handling for the MP virtual link */ 975 if (linkNum == NG_PPP_BUNDLE_LINKNUM) 976 return ng_ppp_mp_output(node, m, meta); 977 978 /* Prepend address and control field (unless compressed) */ 979 if (proto == PROT_LCP || !link->conf.enableACFComp) { 980 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) { 981 NG_FREE_META(meta); 982 return (ENOBUFS); 983 } 984 } 985 986 /* Deliver frame */ 987 len = m->m_pkthdr.len; 988 NG_SEND_DATA(error, link->hook, m, meta); 989 990 /* Update stats and 'bytes in queue' counter */ 991 if (error == 0) { 992 link->stats.xmitFrames++; 993 link->stats.xmitOctets += len; 994 link->bytesInQueue += len; 995 getmicrouptime(&link->lastWrite); 996 } 997 return error; 998 } 999 1000 /* 1001 * Handle an incoming multi-link fragment 1002 * 1003 * The fragment reassembly algorithm is somewhat complex. This is mainly 1004 * because we are required not to reorder the reconstructed packets, yet 1005 * fragments are only guaranteed to arrive in order on a per-link basis. 1006 * In other words, when we have a complete packet ready, but the previous 1007 * packet is still incomplete, we have to decide between delivering the 1008 * complete packet and throwing away the incomplete one, or waiting to 1009 * see if the remainder of the incomplete one arrives, at which time we 1010 * can deliver both packets, in order. 1011 * 1012 * This problem is exacerbated by "sequence number slew", which is when 1013 * the sequence numbers coming in from different links are far apart from 1014 * each other. In particular, certain unnamed equipment (*cough* Ascend) 1015 * has been seen to generate sequence number slew of up to 10 on an ISDN 1016 * 2B-channel MP link. There is nothing invalid about sequence number slew 1017 * but it makes the reasssembly process have to work harder. 1018 * 1019 * However, the peer is required to transmit fragments in order on each 1020 * link. That means if we define MSEQ as the minimum over all links of 1021 * the highest sequence number received on that link, then we can always 1022 * give up any hope of receiving a fragment with sequence number < MSEQ in 1023 * the future (all of this using 'wraparound' sequence number space). 1024 * Therefore we can always immediately throw away incomplete packets 1025 * missing fragments with sequence numbers < MSEQ. 1026 * 1027 * Here is an overview of our algorithm: 1028 * 1029 * o Received fragments are inserted into a queue, for which we 1030 * maintain these invariants between calls to this function: 1031 * 1032 * - Fragments are ordered in the queue by sequence number 1033 * - If a complete packet is at the head of the queue, then 1034 * the first fragment in the packet has seq# > MSEQ + 1 1035 * (otherwise, we could deliver it immediately) 1036 * - If any fragments have seq# < MSEQ, then they are necessarily 1037 * part of a packet whose missing seq#'s are all > MSEQ (otherwise, 1038 * we can throw them away because they'll never be completed) 1039 * - The queue contains at most MP_MAX_QUEUE_LEN fragments 1040 * 1041 * o We have a periodic timer that checks the queue for the first 1042 * complete packet that has been sitting in the queue "too long". 1043 * When one is detected, all previous (incomplete) fragments are 1044 * discarded, their missing fragments are declared lost and MSEQ 1045 * is increased. 1046 * 1047 * o If we recieve a fragment with seq# < MSEQ, we throw it away 1048 * because we've already delcared it lost. 1049 * 1050 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM. 1051 */ 1052 static int 1053 ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta) 1054 { 1055 const priv_p priv = node->private; 1056 struct ng_ppp_link *const link = &priv->links[linkNum]; 1057 struct ng_ppp_frag frag0, *frag = &frag0; 1058 struct ng_ppp_frag *qent; 1059 int i, diff, inserted; 1060 1061 /* Stats */ 1062 priv->bundleStats.recvFrames++; 1063 priv->bundleStats.recvOctets += m->m_pkthdr.len; 1064 1065 /* Extract fragment information from MP header */ 1066 if (priv->conf.recvShortSeq) { 1067 u_int16_t shdr; 1068 1069 if (m->m_pkthdr.len < 2) { 1070 link->stats.runts++; 1071 NG_FREE_DATA(m, meta); 1072 return (EINVAL); 1073 } 1074 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) { 1075 NG_FREE_META(meta); 1076 return (ENOBUFS); 1077 } 1078 shdr = ntohs(*mtod(m, u_int16_t *)); 1079 frag->seq = MP_SHORT_EXTEND(shdr); 1080 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0; 1081 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0; 1082 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq); 1083 m_adj(m, 2); 1084 } else { 1085 u_int32_t lhdr; 1086 1087 if (m->m_pkthdr.len < 4) { 1088 link->stats.runts++; 1089 NG_FREE_DATA(m, meta); 1090 return (EINVAL); 1091 } 1092 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) { 1093 NG_FREE_META(meta); 1094 return (ENOBUFS); 1095 } 1096 lhdr = ntohl(*mtod(m, u_int32_t *)); 1097 frag->seq = MP_LONG_EXTEND(lhdr); 1098 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0; 1099 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0; 1100 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq); 1101 m_adj(m, 4); 1102 } 1103 frag->data = m; 1104 frag->meta = meta; 1105 getmicrouptime(&frag->timestamp); 1106 1107 /* If sequence number is < MSEQ, we've already declared this 1108 fragment as lost, so we have no choice now but to drop it */ 1109 if (diff < 0) { 1110 link->stats.dropFragments++; 1111 NG_FREE_DATA(m, meta); 1112 return (0); 1113 } 1114 1115 /* Update highest received sequence number on this link and MSEQ */ 1116 priv->mseq = link->seq = frag->seq; 1117 for (i = 0; i < priv->numActiveLinks; i++) { 1118 struct ng_ppp_link *const alink = 1119 &priv->links[priv->activeLinks[i]]; 1120 1121 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0) 1122 priv->mseq = alink->seq; 1123 } 1124 1125 /* Allocate a new frag struct for the queue */ 1126 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT); 1127 if (frag == NULL) { 1128 NG_FREE_DATA(m, meta); 1129 ng_ppp_frag_process(node); 1130 return (ENOMEM); 1131 } 1132 *frag = frag0; 1133 1134 /* Add fragment to queue, which is sorted by sequence number */ 1135 inserted = 0; 1136 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) { 1137 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq); 1138 if (diff > 0) { 1139 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent); 1140 inserted = 1; 1141 break; 1142 } else if (diff == 0) { /* should never happen! */ 1143 link->stats.dupFragments++; 1144 NG_FREE_DATA(frag->data, frag->meta); 1145 FREE(frag, M_NETGRAPH); 1146 return (EINVAL); 1147 } 1148 } 1149 if (!inserted) 1150 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent); 1151 priv->qlen++; 1152 1153 /* Process the queue */ 1154 return ng_ppp_frag_process(node); 1155 } 1156 1157 /* 1158 * Examine our list of fragments, and determine if there is a 1159 * complete and deliverable packet at the head of the list. 1160 * Return 1 if so, zero otherwise. 1161 */ 1162 static int 1163 ng_ppp_check_packet(node_p node) 1164 { 1165 const priv_p priv = node->private; 1166 struct ng_ppp_frag *qent, *qnext; 1167 1168 /* Check for empty queue */ 1169 if (TAILQ_EMPTY(&priv->frags)) 1170 return (0); 1171 1172 /* Check first fragment is the start of a deliverable packet */ 1173 qent = TAILQ_FIRST(&priv->frags); 1174 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1) 1175 return (0); 1176 1177 /* Check that all the fragments are there */ 1178 while (!qent->last) { 1179 qnext = TAILQ_NEXT(qent, f_qent); 1180 if (qnext == NULL) /* end of queue */ 1181 return (0); 1182 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)) 1183 return (0); 1184 qent = qnext; 1185 } 1186 1187 /* Got one */ 1188 return (1); 1189 } 1190 1191 /* 1192 * Pull a completed packet off the head of the incoming fragment queue. 1193 * This assumes there is a completed packet there to pull off. 1194 */ 1195 static void 1196 ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap) 1197 { 1198 const priv_p priv = node->private; 1199 struct ng_ppp_frag *qent, *qnext; 1200 struct mbuf *m = NULL, *tail; 1201 1202 qent = TAILQ_FIRST(&priv->frags); 1203 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first, 1204 ("%s: no packet", __FUNCTION__)); 1205 for (tail = NULL; qent != NULL; qent = qnext) { 1206 qnext = TAILQ_NEXT(qent, f_qent); 1207 KASSERT(!TAILQ_EMPTY(&priv->frags), 1208 ("%s: empty q", __FUNCTION__)); 1209 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1210 if (tail == NULL) { 1211 tail = m = qent->data; 1212 *metap = qent->meta; /* inherit first frag's meta */ 1213 } else { 1214 m->m_pkthdr.len += qent->data->m_pkthdr.len; 1215 tail->m_next = qent->data; 1216 NG_FREE_META(qent->meta); /* drop other frags' metas */ 1217 } 1218 while (tail->m_next != NULL) 1219 tail = tail->m_next; 1220 if (qent->last) 1221 qnext = NULL; 1222 FREE(qent, M_NETGRAPH); 1223 priv->qlen--; 1224 } 1225 *mp = m; 1226 } 1227 1228 /* 1229 * Trim fragments from the queue whose packets can never be completed. 1230 * This assumes a complete packet is NOT at the beginning of the queue. 1231 * Returns 1 if fragments were removed, zero otherwise. 1232 */ 1233 static int 1234 ng_ppp_frag_trim(node_p node) 1235 { 1236 const priv_p priv = node->private; 1237 struct ng_ppp_frag *qent, *qnext = NULL; 1238 int removed = 0; 1239 1240 /* Scan for "dead" fragments and remove them */ 1241 while (1) { 1242 int dead = 0; 1243 1244 /* If queue is empty, we're done */ 1245 if (TAILQ_EMPTY(&priv->frags)) 1246 break; 1247 1248 /* Determine whether first fragment can ever be completed */ 1249 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1250 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0) 1251 break; 1252 qnext = TAILQ_NEXT(qent, f_qent); 1253 KASSERT(qnext != NULL, 1254 ("%s: last frag < MSEQ?", __FUNCTION__)); 1255 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq) 1256 || qent->last || qnext->first) { 1257 dead = 1; 1258 break; 1259 } 1260 } 1261 if (!dead) 1262 break; 1263 1264 /* Remove fragment and all others in the same packet */ 1265 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) { 1266 KASSERT(!TAILQ_EMPTY(&priv->frags), 1267 ("%s: empty q", __FUNCTION__)); 1268 priv->bundleStats.dropFragments++; 1269 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1270 NG_FREE_DATA(qent->data, qent->meta); 1271 FREE(qent, M_NETGRAPH); 1272 priv->qlen--; 1273 removed = 1; 1274 } 1275 } 1276 return (removed); 1277 } 1278 1279 /* 1280 * Run the queue, restoring the queue invariants 1281 */ 1282 static int 1283 ng_ppp_frag_process(node_p node) 1284 { 1285 const priv_p priv = node->private; 1286 struct mbuf *m; 1287 meta_p meta; 1288 1289 /* Deliver any deliverable packets */ 1290 while (ng_ppp_check_packet(node)) { 1291 ng_ppp_get_packet(node, &m, &meta); 1292 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta); 1293 } 1294 1295 /* Delete dead fragments and try again */ 1296 if (ng_ppp_frag_trim(node)) { 1297 while (ng_ppp_check_packet(node)) { 1298 ng_ppp_get_packet(node, &m, &meta); 1299 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta); 1300 } 1301 } 1302 1303 /* Check for stale fragments while we're here */ 1304 ng_ppp_frag_checkstale(node); 1305 1306 /* Check queue length */ 1307 if (priv->qlen > MP_MAX_QUEUE_LEN) { 1308 struct ng_ppp_frag *qent; 1309 int i; 1310 1311 /* Get oldest fragment */ 1312 KASSERT(!TAILQ_EMPTY(&priv->frags), 1313 ("%s: empty q", __FUNCTION__)); 1314 qent = TAILQ_FIRST(&priv->frags); 1315 1316 /* Bump MSEQ if necessary */ 1317 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) { 1318 priv->mseq = qent->seq; 1319 for (i = 0; i < priv->numActiveLinks; i++) { 1320 struct ng_ppp_link *const alink = 1321 &priv->links[priv->activeLinks[i]]; 1322 1323 if (MP_RECV_SEQ_DIFF(priv, 1324 alink->seq, priv->mseq) < 0) 1325 alink->seq = priv->mseq; 1326 } 1327 } 1328 1329 /* Drop it */ 1330 priv->bundleStats.dropFragments++; 1331 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1332 NG_FREE_DATA(qent->data, qent->meta); 1333 FREE(qent, M_NETGRAPH); 1334 priv->qlen--; 1335 1336 /* Process queue again */ 1337 return ng_ppp_frag_process(node); 1338 } 1339 1340 /* Done */ 1341 return (0); 1342 } 1343 1344 /* 1345 * Check for 'stale' completed packets that need to be delivered 1346 * 1347 * If a link goes down or has a temporary failure, MSEQ can get 1348 * "stuck", because no new incoming fragments appear on that link. 1349 * This can cause completed packets to never get delivered if 1350 * their sequence numbers are all > MSEQ + 1. 1351 * 1352 * This routine checks how long all of the completed packets have 1353 * been sitting in the queue, and if too long, removes fragments 1354 * from the queue and increments MSEQ to allow them to be delivered. 1355 */ 1356 static void 1357 ng_ppp_frag_checkstale(node_p node) 1358 { 1359 const priv_p priv = node->private; 1360 struct ng_ppp_frag *qent, *beg, *end; 1361 struct timeval now, age; 1362 struct mbuf *m; 1363 meta_p meta; 1364 int i, seq; 1365 1366 now.tv_sec = 0; /* uninitialized state */ 1367 while (1) { 1368 1369 /* If queue is empty, we're done */ 1370 if (TAILQ_EMPTY(&priv->frags)) 1371 break; 1372 1373 /* Find the first complete packet in the queue */ 1374 beg = end = NULL; 1375 seq = TAILQ_FIRST(&priv->frags)->seq; 1376 TAILQ_FOREACH(qent, &priv->frags, f_qent) { 1377 if (qent->first) 1378 beg = qent; 1379 else if (qent->seq != seq) 1380 beg = NULL; 1381 if (beg != NULL && qent->last) { 1382 end = qent; 1383 break; 1384 } 1385 seq = MP_NEXT_RECV_SEQ(priv, seq); 1386 } 1387 1388 /* If none found, exit */ 1389 if (end == NULL) 1390 break; 1391 1392 /* Get current time (we assume we've been up for >= 1 second) */ 1393 if (now.tv_sec == 0) 1394 getmicrouptime(&now); 1395 1396 /* Check if packet has been queued too long */ 1397 age = now; 1398 timevalsub(&age, &beg->timestamp); 1399 if (timevalcmp(&age, &ng_ppp_max_staleness, < )) 1400 break; 1401 1402 /* Throw away junk fragments in front of the completed packet */ 1403 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) { 1404 KASSERT(!TAILQ_EMPTY(&priv->frags), 1405 ("%s: empty q", __FUNCTION__)); 1406 priv->bundleStats.dropFragments++; 1407 TAILQ_REMOVE(&priv->frags, qent, f_qent); 1408 NG_FREE_DATA(qent->data, qent->meta); 1409 FREE(qent, M_NETGRAPH); 1410 priv->qlen--; 1411 } 1412 1413 /* Extract completed packet */ 1414 ng_ppp_get_packet(node, &m, &meta); 1415 1416 /* Bump MSEQ if necessary */ 1417 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) { 1418 priv->mseq = end->seq; 1419 for (i = 0; i < priv->numActiveLinks; i++) { 1420 struct ng_ppp_link *const alink = 1421 &priv->links[priv->activeLinks[i]]; 1422 1423 if (MP_RECV_SEQ_DIFF(priv, 1424 alink->seq, priv->mseq) < 0) 1425 alink->seq = priv->mseq; 1426 } 1427 } 1428 1429 /* Deliver packet */ 1430 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta); 1431 } 1432 } 1433 1434 /* 1435 * Periodically call ng_ppp_frag_checkstale() 1436 */ 1437 static void 1438 ng_ppp_frag_timeout(void *arg) 1439 { 1440 const node_p node = arg; 1441 const priv_p priv = node->private; 1442 int s = splnet(); 1443 1444 /* Handle the race where shutdown happens just before splnet() above */ 1445 if ((node->flags & NG_INVALID) != 0) { 1446 ng_unref(node); 1447 splx(s); 1448 return; 1449 } 1450 1451 /* Reset timer state after timeout */ 1452 KASSERT(priv->timerActive, ("%s: !timerActive", __FUNCTION__)); 1453 priv->timerActive = 0; 1454 KASSERT(node->refs > 1, ("%s: refs=%d", __FUNCTION__, node->refs)); 1455 ng_unref(node); 1456 1457 /* Start timer again */ 1458 ng_ppp_start_frag_timer(node); 1459 1460 /* Scan the fragment queue */ 1461 ng_ppp_frag_checkstale(node); 1462 splx(s); 1463 } 1464 1465 /* 1466 * Deliver a frame out on the bundle, i.e., figure out how to fragment 1467 * the frame across the individual PPP links and do so. 1468 */ 1469 static int 1470 ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta) 1471 { 1472 const priv_p priv = node->private; 1473 int distrib[NG_PPP_MAX_LINKS]; 1474 int firstFragment; 1475 int activeLinkNum; 1476 1477 /* At least one link must be active */ 1478 if (priv->numActiveLinks == 0) { 1479 NG_FREE_DATA(m, meta); 1480 return (ENETDOWN); 1481 } 1482 1483 /* Round-robin strategy */ 1484 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) { 1485 activeLinkNum = priv->lastLink++ % priv->numActiveLinks; 1486 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0])); 1487 distrib[activeLinkNum] = m->m_pkthdr.len; 1488 goto deliver; 1489 } 1490 1491 /* Strategy when all links are equivalent (optimize the common case) */ 1492 if (priv->allLinksEqual) { 1493 const int fraction = m->m_pkthdr.len / priv->numActiveLinks; 1494 int i, remain; 1495 1496 for (i = 0; i < priv->numActiveLinks; i++) 1497 distrib[priv->lastLink++ % priv->numActiveLinks] 1498 = fraction; 1499 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks); 1500 while (remain > 0) { 1501 distrib[priv->lastLink++ % priv->numActiveLinks]++; 1502 remain--; 1503 } 1504 goto deliver; 1505 } 1506 1507 /* Strategy when all links are not equivalent */ 1508 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib); 1509 1510 deliver: 1511 /* Update stats */ 1512 priv->bundleStats.xmitFrames++; 1513 priv->bundleStats.xmitOctets += m->m_pkthdr.len; 1514 1515 /* Send alloted portions of frame out on the link(s) */ 1516 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1; 1517 activeLinkNum >= 0; activeLinkNum--) { 1518 const int linkNum = priv->activeLinks[activeLinkNum]; 1519 struct ng_ppp_link *const link = &priv->links[linkNum]; 1520 1521 /* Deliver fragment(s) out the next link */ 1522 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) { 1523 int len, lastFragment, error; 1524 struct mbuf *m2; 1525 meta_p meta2; 1526 1527 /* Calculate fragment length; don't exceed link MTU */ 1528 len = distrib[activeLinkNum]; 1529 if (len > link->conf.mru) 1530 len = link->conf.mru; 1531 distrib[activeLinkNum] -= len; 1532 lastFragment = (len == m->m_pkthdr.len); 1533 1534 /* Split off next fragment as "m2" */ 1535 m2 = m; 1536 if (!lastFragment) { 1537 struct mbuf *n = m_split(m, len, M_NOWAIT); 1538 1539 if (n == NULL) { 1540 NG_FREE_DATA(m, meta); 1541 return (ENOMEM); 1542 } 1543 m = n; 1544 } 1545 1546 /* Prepend MP header */ 1547 if (priv->conf.xmitShortSeq) { 1548 u_int16_t shdr; 1549 1550 shdr = priv->xseq; 1551 priv->xseq = 1552 (priv->xseq + 1) & MP_SHORT_SEQ_MASK; 1553 if (firstFragment) 1554 shdr |= MP_SHORT_FIRST_FLAG; 1555 if (lastFragment) 1556 shdr |= MP_SHORT_LAST_FLAG; 1557 shdr = htons(shdr); 1558 m2 = ng_ppp_prepend(m2, &shdr, 2); 1559 } else { 1560 u_int32_t lhdr; 1561 1562 lhdr = priv->xseq; 1563 priv->xseq = 1564 (priv->xseq + 1) & MP_LONG_SEQ_MASK; 1565 if (firstFragment) 1566 lhdr |= MP_LONG_FIRST_FLAG; 1567 if (lastFragment) 1568 lhdr |= MP_LONG_LAST_FLAG; 1569 lhdr = htonl(lhdr); 1570 m2 = ng_ppp_prepend(m2, &lhdr, 4); 1571 } 1572 if (m2 == NULL) { 1573 if (!lastFragment) 1574 m_freem(m); 1575 NG_FREE_META(meta); 1576 return (ENOBUFS); 1577 } 1578 1579 /* Copy the meta information, if any */ 1580 meta2 = lastFragment ? meta : ng_copy_meta(meta); 1581 1582 /* Send fragment */ 1583 error = ng_ppp_output(node, 0, 1584 PROT_MP, linkNum, m2, meta2); 1585 if (error != 0) { 1586 if (!lastFragment) 1587 NG_FREE_DATA(m, meta); 1588 return (error); 1589 } 1590 } 1591 } 1592 1593 /* Done */ 1594 return (0); 1595 } 1596 1597 /* 1598 * Computing the optimal fragmentation 1599 * ----------------------------------- 1600 * 1601 * This routine tries to compute the optimal fragmentation pattern based 1602 * on each link's latency, bandwidth, and calculated additional latency. 1603 * The latter quantity is the additional latency caused by previously 1604 * written data that has not been transmitted yet. 1605 * 1606 * This algorithm is only useful when not all of the links have the 1607 * same latency and bandwidth values. 1608 * 1609 * The essential idea is to make the last bit of each fragment of the 1610 * frame arrive at the opposite end at the exact same time. This greedy 1611 * algorithm is optimal, in that no other scheduling could result in any 1612 * packet arriving any sooner unless packets are delivered out of order. 1613 * 1614 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and 1615 * latency l_i (in miliseconds). Consider the function function f_i(t) 1616 * which is equal to the number of bytes that will have arrived at 1617 * the peer after t miliseconds if we start writing continuously at 1618 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i). 1619 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i). 1620 * Note that the y-intersect is always <= zero because latency can't be 1621 * negative. Note also that really the function is f_i(t) except when 1622 * f_i(t) is negative, in which case the function is zero. To take 1623 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }. 1624 * So the actual number of bytes that will have arrived at the peer after 1625 * t miliseconds is f_i(t) * Q_i(t). 1626 * 1627 * At any given time, each link has some additional latency a_i >= 0 1628 * due to previously written fragment(s) which are still in the queue. 1629 * This value is easily computed from the time since last transmission, 1630 * the previous latency value, the number of bytes written, and the 1631 * link's bandwidth. 1632 * 1633 * Assume that l_i includes any a_i already, and that the links are 1634 * sorted by latency, so that l_i <= l_{i+1}. 1635 * 1636 * Let N be the total number of bytes in the current frame we are sending. 1637 * 1638 * Suppose we were to start writing bytes at time t = 0 on all links 1639 * simultaneously, which is the most we can possibly do. Then let 1640 * F(t) be equal to the total number of bytes received by the peer 1641 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)). 1642 * 1643 * Our goal is simply this: fragment the frame across the links such 1644 * that the peer is able to reconstruct the completed frame as soon as 1645 * possible, i.e., at the least possible value of t. Call this value t_0. 1646 * 1647 * Then it follows that F(t_0) = N. Our strategy is first to find the value 1648 * of t_0, and then deduce how many bytes to write to each link. 1649 * 1650 * Rewriting F(t_0): 1651 * 1652 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) ) 1653 * 1654 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will 1655 * lie in one of these ranges. To find it, we just need to find the i such 1656 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values 1657 * for Q_i() in this range, plug in the remaining values, solving for t_0. 1658 * 1659 * Once t_0 is known, then the number of bytes to send on link i is 1660 * just f_i(t_0) * Q_i(t_0). 1661 * 1662 * In other words, we start allocating bytes to the links one at a time. 1663 * We keep adding links until the frame is completely sent. Some links 1664 * may not get any bytes because their latency is too high. 1665 * 1666 * Is all this work really worth the trouble? Depends on the situation. 1667 * The bigger the ratio of computer speed to link speed, and the more 1668 * important total bundle latency is (e.g., for interactive response time), 1669 * the more it's worth it. There is however the cost of calling this 1670 * function for every frame. The running time is O(n^2) where n is the 1671 * number of links that receive a non-zero number of bytes. 1672 * 1673 * Since latency is measured in miliseconds, the "resolution" of this 1674 * algorithm is one milisecond. 1675 * 1676 * To avoid this algorithm altogether, configure all links to have the 1677 * same latency and bandwidth. 1678 */ 1679 static void 1680 ng_ppp_mp_strategy(node_p node, int len, int *distrib) 1681 { 1682 const priv_p priv = node->private; 1683 int latency[NG_PPP_MAX_LINKS]; 1684 int sortByLatency[NG_PPP_MAX_LINKS]; 1685 int activeLinkNum; 1686 int t0, total, topSum, botSum; 1687 struct timeval now; 1688 int i, numFragments; 1689 1690 /* If only one link, this gets real easy */ 1691 if (priv->numActiveLinks == 1) { 1692 distrib[0] = len; 1693 return; 1694 } 1695 1696 /* Get current time */ 1697 getmicrouptime(&now); 1698 1699 /* Compute latencies for each link at this point in time */ 1700 for (activeLinkNum = 0; 1701 activeLinkNum < priv->numActiveLinks; activeLinkNum++) { 1702 struct ng_ppp_link *alink; 1703 struct timeval diff; 1704 int xmitBytes; 1705 1706 /* Start with base latency value */ 1707 alink = &priv->links[priv->activeLinks[activeLinkNum]]; 1708 latency[activeLinkNum] = alink->conf.latency; 1709 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */ 1710 1711 /* Any additional latency? */ 1712 if (alink->bytesInQueue == 0) 1713 continue; 1714 1715 /* Compute time delta since last write */ 1716 diff = now; 1717 timevalsub(&diff, &alink->lastWrite); 1718 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */ 1719 alink->bytesInQueue = 0; 1720 continue; 1721 } 1722 1723 /* How many bytes could have transmitted since last write? */ 1724 xmitBytes = (alink->conf.bandwidth * diff.tv_sec) 1725 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100; 1726 alink->bytesInQueue -= xmitBytes; 1727 if (alink->bytesInQueue < 0) 1728 alink->bytesInQueue = 0; 1729 else 1730 latency[activeLinkNum] += 1731 (100 * alink->bytesInQueue) / alink->conf.bandwidth; 1732 } 1733 1734 /* Sort active links by latency */ 1735 compareLatencies = latency; 1736 qsort(sortByLatency, 1737 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp); 1738 compareLatencies = NULL; 1739 1740 /* Find the interval we need (add links in sortByLatency[] order) */ 1741 for (numFragments = 1; 1742 numFragments < priv->numActiveLinks; numFragments++) { 1743 for (total = i = 0; i < numFragments; i++) { 1744 int flowTime; 1745 1746 flowTime = latency[sortByLatency[numFragments]] 1747 - latency[sortByLatency[i]]; 1748 total += ((flowTime * priv->links[ 1749 priv->activeLinks[sortByLatency[i]]].conf.bandwidth) 1750 + 99) / 100; 1751 } 1752 if (total >= len) 1753 break; 1754 } 1755 1756 /* Solve for t_0 in that interval */ 1757 for (topSum = botSum = i = 0; i < numFragments; i++) { 1758 int bw = priv->links[ 1759 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1760 1761 topSum += latency[sortByLatency[i]] * bw; /* / 100 */ 1762 botSum += bw; /* / 100 */ 1763 } 1764 t0 = ((len * 100) + topSum + botSum / 2) / botSum; 1765 1766 /* Compute f_i(t_0) all i */ 1767 bzero(distrib, priv->numActiveLinks * sizeof(*distrib)); 1768 for (total = i = 0; i < numFragments; i++) { 1769 int bw = priv->links[ 1770 priv->activeLinks[sortByLatency[i]]].conf.bandwidth; 1771 1772 distrib[sortByLatency[i]] = 1773 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100; 1774 total += distrib[sortByLatency[i]]; 1775 } 1776 1777 /* Deal with any rounding error */ 1778 if (total < len) { 1779 struct ng_ppp_link *fastLink = 1780 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1781 int fast = 0; 1782 1783 /* Find the fastest link */ 1784 for (i = 1; i < numFragments; i++) { 1785 struct ng_ppp_link *const link = 1786 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1787 1788 if (link->conf.bandwidth > fastLink->conf.bandwidth) { 1789 fast = i; 1790 fastLink = link; 1791 } 1792 } 1793 distrib[sortByLatency[fast]] += len - total; 1794 } else while (total > len) { 1795 struct ng_ppp_link *slowLink = 1796 &priv->links[priv->activeLinks[sortByLatency[0]]]; 1797 int delta, slow = 0; 1798 1799 /* Find the slowest link that still has bytes to remove */ 1800 for (i = 1; i < numFragments; i++) { 1801 struct ng_ppp_link *const link = 1802 &priv->links[priv->activeLinks[sortByLatency[i]]]; 1803 1804 if (distrib[sortByLatency[slow]] == 0 1805 || (distrib[sortByLatency[i]] > 0 1806 && link->conf.bandwidth < 1807 slowLink->conf.bandwidth)) { 1808 slow = i; 1809 slowLink = link; 1810 } 1811 } 1812 delta = total - len; 1813 if (delta > distrib[sortByLatency[slow]]) 1814 delta = distrib[sortByLatency[slow]]; 1815 distrib[sortByLatency[slow]] -= delta; 1816 total -= delta; 1817 } 1818 } 1819 1820 /* 1821 * Compare two integers 1822 */ 1823 static int 1824 ng_ppp_intcmp(const void *v1, const void *v2) 1825 { 1826 const int index1 = *((const int *) v1); 1827 const int index2 = *((const int *) v2); 1828 1829 return compareLatencies[index1] - compareLatencies[index2]; 1830 } 1831 1832 /* 1833 * Prepend a possibly compressed PPP protocol number in front of a frame 1834 */ 1835 static struct mbuf * 1836 ng_ppp_addproto(struct mbuf *m, int proto, int compOK) 1837 { 1838 if (compOK && PROT_COMPRESSABLE(proto)) { 1839 u_char pbyte = (u_char)proto; 1840 1841 return ng_ppp_prepend(m, &pbyte, 1); 1842 } else { 1843 u_int16_t pword = htons((u_int16_t)proto); 1844 1845 return ng_ppp_prepend(m, &pword, 2); 1846 } 1847 } 1848 1849 /* 1850 * Prepend some bytes to an mbuf 1851 */ 1852 static struct mbuf * 1853 ng_ppp_prepend(struct mbuf *m, const void *buf, int len) 1854 { 1855 M_PREPEND(m, len, M_NOWAIT); 1856 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL)) 1857 return (NULL); 1858 bcopy(buf, mtod(m, u_char *), len); 1859 return (m); 1860 } 1861 1862 /* 1863 * Update private information that is derived from other private information 1864 */ 1865 static void 1866 ng_ppp_update(node_p node, int newConf) 1867 { 1868 const priv_p priv = node->private; 1869 int i; 1870 1871 /* Update active status for VJ Compression */ 1872 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL 1873 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL 1874 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL 1875 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL; 1876 1877 /* Increase latency for each link an amount equal to one MP header */ 1878 if (newConf) { 1879 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1880 int hdrBytes; 1881 1882 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2) 1883 + (priv->links[i].conf.enableProtoComp ? 1 : 2) 1884 + (priv->conf.xmitShortSeq ? 2 : 4); 1885 priv->links[i].conf.latency += 1886 ((hdrBytes * priv->links[i].conf.bandwidth) + 50) 1887 / 100; 1888 } 1889 } 1890 1891 /* Update list of active links */ 1892 bzero(&priv->activeLinks, sizeof(priv->activeLinks)); 1893 priv->numActiveLinks = 0; 1894 priv->allLinksEqual = 1; 1895 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1896 struct ng_ppp_link *const link = &priv->links[i]; 1897 1898 /* Is link active? */ 1899 if (link->conf.enableLink && link->hook != NULL) { 1900 struct ng_ppp_link *link0; 1901 1902 /* Add link to list of active links */ 1903 priv->activeLinks[priv->numActiveLinks++] = i; 1904 link0 = &priv->links[priv->activeLinks[0]]; 1905 1906 /* Determine if all links are still equal */ 1907 if (link->conf.latency != link0->conf.latency 1908 || link->conf.bandwidth != link0->conf.bandwidth) 1909 priv->allLinksEqual = 0; 1910 1911 /* Initialize rec'd sequence number */ 1912 if (link->seq == MP_NOSEQ) { 1913 link->seq = (link == link0) ? 1914 MP_INITIAL_SEQ : link0->seq; 1915 } 1916 } else 1917 link->seq = MP_NOSEQ; 1918 } 1919 1920 /* Update MP state as multi-link is active or not */ 1921 if (priv->conf.enableMultilink && priv->numActiveLinks > 0) 1922 ng_ppp_start_frag_timer(node); 1923 else { 1924 ng_ppp_stop_frag_timer(node); 1925 ng_ppp_frag_reset(node); 1926 priv->xseq = MP_INITIAL_SEQ; 1927 priv->mseq = MP_INITIAL_SEQ; 1928 for (i = 0; i < NG_PPP_MAX_LINKS; i++) { 1929 struct ng_ppp_link *const link = &priv->links[i]; 1930 1931 bzero(&link->lastWrite, sizeof(link->lastWrite)); 1932 link->bytesInQueue = 0; 1933 link->seq = MP_NOSEQ; 1934 } 1935 } 1936 } 1937 1938 /* 1939 * Determine if a new configuration would represent a valid change 1940 * from the current configuration and link activity status. 1941 */ 1942 static int 1943 ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf) 1944 { 1945 const priv_p priv = node->private; 1946 int i, newNumLinksActive; 1947 1948 /* Check per-link config and count how many links would be active */ 1949 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) { 1950 if (newConf->links[i].enableLink && priv->links[i].hook != NULL) 1951 newNumLinksActive++; 1952 if (!newConf->links[i].enableLink) 1953 continue; 1954 if (newConf->links[i].mru < MP_MIN_LINK_MRU) 1955 return (0); 1956 if (newConf->links[i].bandwidth == 0) 1957 return (0); 1958 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH) 1959 return (0); 1960 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY) 1961 return (0); 1962 } 1963 1964 /* Check bundle parameters */ 1965 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU) 1966 return (0); 1967 1968 /* Disallow changes to multi-link configuration while MP is active */ 1969 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) { 1970 if (!priv->conf.enableMultilink 1971 != !newConf->bund.enableMultilink 1972 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq 1973 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq) 1974 return (0); 1975 } 1976 1977 /* At most one link can be active unless multi-link is enabled */ 1978 if (!newConf->bund.enableMultilink && newNumLinksActive > 1) 1979 return (0); 1980 1981 /* Configuration change would be valid */ 1982 return (1); 1983 } 1984 1985 /* 1986 * Free all entries in the fragment queue 1987 */ 1988 static void 1989 ng_ppp_frag_reset(node_p node) 1990 { 1991 const priv_p priv = node->private; 1992 struct ng_ppp_frag *qent, *qnext; 1993 1994 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) { 1995 qnext = TAILQ_NEXT(qent, f_qent); 1996 NG_FREE_DATA(qent->data, qent->meta); 1997 FREE(qent, M_NETGRAPH); 1998 } 1999 TAILQ_INIT(&priv->frags); 2000 priv->qlen = 0; 2001 } 2002 2003 /* 2004 * Start fragment queue timer 2005 */ 2006 static void 2007 ng_ppp_start_frag_timer(node_p node) 2008 { 2009 const priv_p priv = node->private; 2010 2011 if (!priv->timerActive) { 2012 priv->fragTimer = timeout(ng_ppp_frag_timeout, 2013 node, MP_FRAGTIMER_INTERVAL); 2014 priv->timerActive = 1; 2015 node->refs++; 2016 } 2017 } 2018 2019 /* 2020 * Stop fragment queue timer 2021 */ 2022 static void 2023 ng_ppp_stop_frag_timer(node_p node) 2024 { 2025 const priv_p priv = node->private; 2026 2027 if (priv->timerActive) { 2028 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer); 2029 priv->timerActive = 0; 2030 KASSERT(node->refs > 1, 2031 ("%s: refs=%d", __FUNCTION__, node->refs)); 2032 ng_unref(node); 2033 } 2034 } 2035 2036