1 2 /* 3 * ng_vjc.c 4 * 5 * Copyright (c) 1996-1999 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: src/sys/netgraph/ng_vjc.c,v 1.9.2.5 2002/07/02 23:44:03 archie Exp $ 40 * $Whistle: ng_vjc.c,v 1.17 1999/11/01 09:24:52 julian Exp $ 41 */ 42 43 /* 44 * This node performs Van Jacobson IP header (de)compression. 45 * You must have included net/slcompress.c in your kernel compilation. 46 */ 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/errno.h> 51 #include <sys/kernel.h> 52 #include <sys/mbuf.h> 53 #include <sys/malloc.h> 54 #include <sys/errno.h> 55 56 #include <netgraph/ng_message.h> 57 #include <netgraph/netgraph.h> 58 #include <netgraph/ng_parse.h> 59 #include "ng_vjc.h" 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/ip.h> 64 #include <netinet/tcp.h> 65 66 #include <net/slcompress.h> 67 68 /* Check agreement with slcompress.c */ 69 #if MAX_STATES != NG_VJC_MAX_CHANNELS 70 #error NG_VJC_MAX_CHANNELS must be the same as MAX_STATES 71 #endif 72 73 /* Maximum length of a compressed TCP VJ header */ 74 #define MAX_VJHEADER 19 75 76 /* Node private data */ 77 struct ng_vjc_private { 78 struct ngm_vjc_config conf; 79 struct slcompress slc; 80 hook_p ip; 81 hook_p vjcomp; 82 hook_p vjuncomp; 83 hook_p vjip; 84 }; 85 typedef struct ng_vjc_private *priv_p; 86 87 #define ERROUT(x) do { error = (x); goto done; } while (0) 88 89 /* Netgraph node methods */ 90 static ng_constructor_t ng_vjc_constructor; 91 static ng_rcvmsg_t ng_vjc_rcvmsg; 92 static ng_shutdown_t ng_vjc_rmnode; 93 static ng_newhook_t ng_vjc_newhook; 94 static ng_rcvdata_t ng_vjc_rcvdata; 95 static ng_disconnect_t ng_vjc_disconnect; 96 97 /* Helper stuff */ 98 static struct mbuf *ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP); 99 100 /* Parse type for struct ngm_vjc_config */ 101 static const struct ng_parse_struct_field ng_vjc_config_type_fields[] 102 = NG_VJC_CONFIG_TYPE_INFO; 103 static const struct ng_parse_type ng_vjc_config_type = { 104 &ng_parse_struct_type, 105 &ng_vjc_config_type_fields 106 }; 107 108 /* Parse type for the 'last_cs' and 'cs_next' fields in struct slcompress, 109 which are pointers converted to integer indices, so parse them that way. */ 110 #if _MACHINE_ARCH == i386 111 #define NG_VJC_TSTATE_PTR_TYPE &ng_parse_uint32_type 112 #else 113 #error Unsupported _MACHINE_ARCH 114 #endif 115 116 /* Parse type for the 'cs_hdr' field in a struct cstate. Ideally we would 117 like to use a 'struct ip' type instead of a simple array of bytes. */ 118 static const struct ng_parse_fixedarray_info ng_vjc_cs_hdr_type_info = { 119 &ng_parse_hint8_type, 120 MAX_HDR 121 }; 122 static const struct ng_parse_type ng_vjc_cs_hdr_type = { 123 &ng_parse_fixedarray_type, 124 &ng_vjc_cs_hdr_type_info 125 }; 126 127 /* Parse type for a struct cstate */ 128 static const struct ng_parse_struct_field ng_vjc_cstate_type_fields[] = { 129 { "cs_next", NG_VJC_TSTATE_PTR_TYPE }, 130 { "cs_hlen", &ng_parse_uint16_type }, 131 { "cs_id", &ng_parse_uint8_type }, 132 { "cs_filler", &ng_parse_uint8_type }, 133 { "cs_hdr", &ng_vjc_cs_hdr_type }, 134 { NULL } 135 }; 136 static const struct ng_parse_type ng_vjc_cstate_type = { 137 &ng_parse_struct_type, 138 &ng_vjc_cstate_type_fields 139 }; 140 141 /* Parse type for an array of MAX_STATES struct cstate's, ie, tstate & rstate */ 142 static const struct ng_parse_fixedarray_info ng_vjc_cstatearray_type_info = { 143 &ng_vjc_cstate_type, 144 MAX_STATES 145 }; 146 static const struct ng_parse_type ng_vjc_cstatearray_type = { 147 &ng_parse_fixedarray_type, 148 &ng_vjc_cstatearray_type_info 149 }; 150 151 /* Parse type for struct slcompress. Keep this in sync with the 152 definition of struct slcompress defined in <net/slcompress.h> */ 153 static const struct ng_parse_struct_field ng_vjc_slcompress_type_fields[] = { 154 { "last_cs", NG_VJC_TSTATE_PTR_TYPE }, 155 { "last_recv", &ng_parse_uint8_type }, 156 { "last_xmit", &ng_parse_uint8_type }, 157 { "flags", &ng_parse_hint16_type }, 158 #ifndef SL_NO_STATS 159 { "sls_packets", &ng_parse_uint32_type }, 160 { "sls_compressed", &ng_parse_uint32_type }, 161 { "sls_searches", &ng_parse_uint32_type }, 162 { "sls_misses", &ng_parse_uint32_type }, 163 { "sls_uncompressedin", &ng_parse_uint32_type }, 164 { "sls_compressedin", &ng_parse_uint32_type }, 165 { "sls_errorin", &ng_parse_uint32_type }, 166 { "sls_tossed", &ng_parse_uint32_type }, 167 #endif 168 { "tstate", &ng_vjc_cstatearray_type }, 169 { "rstate", &ng_vjc_cstatearray_type }, 170 { NULL } 171 }; 172 static const struct ng_parse_type ng_vjc_slcompress_type = { 173 &ng_parse_struct_type, 174 &ng_vjc_slcompress_type_fields 175 }; 176 177 /* List of commands and how to convert arguments to/from ASCII */ 178 static const struct ng_cmdlist ng_vjc_cmds[] = { 179 { 180 NGM_VJC_COOKIE, 181 NGM_VJC_SET_CONFIG, 182 "setconfig", 183 &ng_vjc_config_type, 184 NULL 185 }, 186 { 187 NGM_VJC_COOKIE, 188 NGM_VJC_GET_CONFIG, 189 "getconfig", 190 NULL, 191 &ng_vjc_config_type, 192 }, 193 { 194 NGM_VJC_COOKIE, 195 NGM_VJC_GET_STATE, 196 "getstate", 197 NULL, 198 &ng_vjc_slcompress_type, 199 }, 200 { 201 NGM_VJC_COOKIE, 202 NGM_VJC_CLR_STATS, 203 "clrstats", 204 NULL, 205 NULL, 206 }, 207 { 208 NGM_VJC_COOKIE, 209 NGM_VJC_RECV_ERROR, 210 "recverror", 211 NULL, 212 NULL, 213 }, 214 { 0 } 215 }; 216 217 /* Node type descriptor */ 218 static struct ng_type ng_vjc_typestruct = { 219 NG_VERSION, 220 NG_VJC_NODE_TYPE, 221 NULL, 222 ng_vjc_constructor, 223 ng_vjc_rcvmsg, 224 ng_vjc_rmnode, 225 ng_vjc_newhook, 226 NULL, 227 NULL, 228 ng_vjc_rcvdata, 229 ng_vjc_rcvdata, 230 ng_vjc_disconnect, 231 ng_vjc_cmds 232 }; 233 NETGRAPH_INIT(vjc, &ng_vjc_typestruct); 234 235 /************************************************************************ 236 NETGRAPH NODE METHODS 237 ************************************************************************/ 238 239 /* 240 * Create a new node 241 */ 242 static int 243 ng_vjc_constructor(node_p *nodep) 244 { 245 priv_p priv; 246 int error; 247 248 /* Allocate private structure */ 249 priv = kmalloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 250 if (priv == NULL) 251 return (ENOMEM); 252 253 /* Call generic node constructor */ 254 if ((error = ng_make_node_common(&ng_vjc_typestruct, nodep))) { 255 kfree(priv, M_NETGRAPH); 256 return (error); 257 } 258 (*nodep)->private = priv; 259 260 /* Done */ 261 return (0); 262 } 263 264 /* 265 * Add a new hook 266 */ 267 static int 268 ng_vjc_newhook(node_p node, hook_p hook, const char *name) 269 { 270 const priv_p priv = (priv_p) node->private; 271 hook_p *hookp; 272 273 /* Get hook */ 274 if (strcmp(name, NG_VJC_HOOK_IP) == 0) 275 hookp = &priv->ip; 276 else if (strcmp(name, NG_VJC_HOOK_VJCOMP) == 0) 277 hookp = &priv->vjcomp; 278 else if (strcmp(name, NG_VJC_HOOK_VJUNCOMP) == 0) 279 hookp = &priv->vjuncomp; 280 else if (strcmp(name, NG_VJC_HOOK_VJIP) == 0) 281 hookp = &priv->vjip; 282 else 283 return (EINVAL); 284 285 /* See if already connected */ 286 if (*hookp) 287 return (EISCONN); 288 289 /* OK */ 290 *hookp = hook; 291 return (0); 292 } 293 294 /* 295 * Receive a control message 296 */ 297 static int 298 ng_vjc_rcvmsg(node_p node, struct ng_mesg *msg, 299 const char *raddr, struct ng_mesg **rptr) 300 { 301 const priv_p priv = (priv_p) node->private; 302 struct ng_mesg *resp = NULL; 303 int error = 0; 304 305 /* Check type cookie */ 306 switch (msg->header.typecookie) { 307 case NGM_VJC_COOKIE: 308 switch (msg->header.cmd) { 309 case NGM_VJC_SET_CONFIG: 310 { 311 struct ngm_vjc_config *const c = 312 (struct ngm_vjc_config *) msg->data; 313 314 if (msg->header.arglen != sizeof(*c)) 315 ERROUT(EINVAL); 316 if ((priv->conf.enableComp || priv->conf.enableDecomp) 317 && (c->enableComp || c->enableDecomp)) 318 ERROUT(EALREADY); 319 if (c->enableComp) { 320 if (c->maxChannel > NG_VJC_MAX_CHANNELS - 1 321 || c->maxChannel < NG_VJC_MIN_CHANNELS - 1) 322 ERROUT(EINVAL); 323 } else 324 c->maxChannel = NG_VJC_MAX_CHANNELS - 1; 325 if (c->enableComp != 0 || c->enableDecomp != 0) { 326 bzero(&priv->slc, sizeof(priv->slc)); 327 sl_compress_init(&priv->slc, c->maxChannel); 328 } 329 priv->conf = *c; 330 break; 331 } 332 case NGM_VJC_GET_CONFIG: 333 { 334 struct ngm_vjc_config *conf; 335 336 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT); 337 if (resp == NULL) 338 ERROUT(ENOMEM); 339 conf = (struct ngm_vjc_config *)resp->data; 340 *conf = priv->conf; 341 break; 342 } 343 case NGM_VJC_GET_STATE: 344 { 345 const struct slcompress *const sl0 = &priv->slc; 346 struct slcompress *sl; 347 u_int16_t index; 348 int i; 349 350 /* Get response structure */ 351 NG_MKRESPONSE(resp, msg, sizeof(*sl), M_NOWAIT); 352 if (resp == NULL) 353 ERROUT(ENOMEM); 354 sl = (struct slcompress *)resp->data; 355 *sl = *sl0; 356 357 /* Replace pointers with integer indicies */ 358 if (sl->last_cs != NULL) { 359 index = sl0->last_cs - sl0->tstate; 360 bzero(&sl->last_cs, sizeof(sl->last_cs)); 361 *((u_int16_t *)&sl->last_cs) = index; 362 } 363 for (i = 0; i < MAX_STATES; i++) { 364 struct cstate *const cs = &sl->tstate[i]; 365 366 index = sl0->tstate[i].cs_next - sl0->tstate; 367 bzero(&cs->cs_next, sizeof(cs->cs_next)); 368 *((u_int16_t *)&cs->cs_next) = index; 369 } 370 break; 371 } 372 case NGM_VJC_CLR_STATS: 373 priv->slc.sls_packets = 0; 374 priv->slc.sls_compressed = 0; 375 priv->slc.sls_searches = 0; 376 priv->slc.sls_misses = 0; 377 priv->slc.sls_uncompressedin = 0; 378 priv->slc.sls_compressedin = 0; 379 priv->slc.sls_errorin = 0; 380 priv->slc.sls_tossed = 0; 381 break; 382 case NGM_VJC_RECV_ERROR: 383 sl_uncompress_tcp(NULL, 0, TYPE_ERROR, &priv->slc); 384 break; 385 default: 386 error = EINVAL; 387 break; 388 } 389 break; 390 default: 391 error = EINVAL; 392 break; 393 } 394 if (rptr) 395 *rptr = resp; 396 else if (resp) 397 kfree(resp, M_NETGRAPH); 398 399 done: 400 kfree(msg, M_NETGRAPH); 401 return (error); 402 } 403 404 /* 405 * Receive data 406 */ 407 static int 408 ng_vjc_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 409 { 410 const node_p node = hook->node; 411 const priv_p priv = (priv_p) node->private; 412 int error = 0; 413 414 if (hook == priv->ip) { /* outgoing packet */ 415 u_int type = TYPE_IP; 416 417 /* Compress packet if enabled and proto is TCP */ 418 if (priv->conf.enableComp) { 419 struct ip *ip; 420 421 if ((m = ng_vjc_pulluphdrs(m, 0)) == NULL) { 422 NG_FREE_META(meta); 423 return (ENOBUFS); 424 } 425 ip = mtod(m, struct ip *); 426 if (ip->ip_p == IPPROTO_TCP) { 427 const int origLen = m->m_len; 428 429 type = sl_compress_tcp(m, ip, 430 &priv->slc, priv->conf.compressCID); 431 m->m_pkthdr.len += m->m_len - origLen; 432 } 433 } 434 435 /* Dispatch to the appropriate outgoing hook */ 436 switch (type) { 437 case TYPE_IP: 438 hook = priv->vjip; 439 break; 440 case TYPE_UNCOMPRESSED_TCP: 441 hook = priv->vjuncomp; 442 break; 443 case TYPE_COMPRESSED_TCP: 444 hook = priv->vjcomp; 445 break; 446 default: 447 panic("%s: type=%d", __func__, type); 448 } 449 } else if (hook == priv->vjcomp) { /* incoming compressed packet */ 450 int vjlen, need2pullup; 451 struct mbuf *hm; 452 u_char *hdr; 453 u_int hlen; 454 455 /* Are we decompressing? */ 456 if (!priv->conf.enableDecomp) { 457 NG_FREE_DATA(m, meta); 458 return (ENXIO); 459 } 460 461 /* Pull up the necessary amount from the mbuf */ 462 need2pullup = MAX_VJHEADER; 463 if (need2pullup > m->m_pkthdr.len) 464 need2pullup = m->m_pkthdr.len; 465 if (m->m_len < need2pullup 466 && (m = m_pullup(m, need2pullup)) == NULL) { 467 priv->slc.sls_errorin++; 468 NG_FREE_META(meta); 469 return (ENOBUFS); 470 } 471 472 /* Uncompress packet to reconstruct TCP/IP header */ 473 vjlen = sl_uncompress_tcp_core(mtod(m, u_char *), 474 m->m_len, m->m_pkthdr.len, TYPE_COMPRESSED_TCP, 475 &priv->slc, &hdr, &hlen); 476 if (vjlen <= 0) { 477 NG_FREE_DATA(m, meta); 478 return (EINVAL); 479 } 480 m_adj(m, vjlen); 481 482 /* Copy the reconstructed TCP/IP headers into a new mbuf */ 483 MGETHDR(hm, MB_DONTWAIT, MT_DATA); 484 if (hm == NULL) { 485 priv->slc.sls_errorin++; 486 NG_FREE_DATA(m, meta); 487 return (ENOBUFS); 488 } 489 hm->m_len = 0; 490 hm->m_pkthdr.rcvif = NULL; 491 if (hlen > MHLEN) { /* unlikely, but can happen */ 492 MCLGET(hm, MB_DONTWAIT); 493 if ((hm->m_flags & M_EXT) == 0) { 494 m_freem(hm); 495 priv->slc.sls_errorin++; 496 NG_FREE_DATA(m, meta); 497 return (ENOBUFS); 498 } 499 } 500 bcopy(hdr, mtod(hm, u_char *), hlen); 501 hm->m_len = hlen; 502 503 /* Glue TCP/IP headers and rest of packet together */ 504 hm->m_next = m; 505 hm->m_pkthdr.len = hlen + m->m_pkthdr.len; 506 m = hm; 507 hook = priv->ip; 508 } else if (hook == priv->vjuncomp) { /* incoming uncompressed pkt */ 509 u_char *hdr; 510 u_int hlen; 511 512 /* Are we decompressing? */ 513 if (!priv->conf.enableDecomp) { 514 NG_FREE_DATA(m, meta); 515 return (ENXIO); 516 } 517 518 /* Pull up IP+TCP headers */ 519 if ((m = ng_vjc_pulluphdrs(m, 1)) == NULL) { 520 NG_FREE_META(meta); 521 return (ENOBUFS); 522 } 523 524 /* Run packet through uncompressor */ 525 if (sl_uncompress_tcp_core(mtod(m, u_char *), 526 m->m_len, m->m_pkthdr.len, TYPE_UNCOMPRESSED_TCP, 527 &priv->slc, &hdr, &hlen) < 0) { 528 NG_FREE_DATA(m, meta); 529 return (EINVAL); 530 } 531 hook = priv->ip; 532 } else if (hook == priv->vjip) /* incoming regular packet (bypass) */ 533 hook = priv->ip; 534 else 535 panic("%s: unknown hook", __func__); 536 537 /* Send result back out */ 538 NG_SEND_DATA(error, hook, m, meta); 539 return (error); 540 } 541 542 /* 543 * Shutdown node 544 */ 545 static int 546 ng_vjc_rmnode(node_p node) 547 { 548 const priv_p priv = (priv_p) node->private; 549 550 node->flags |= NG_INVALID; 551 ng_cutlinks(node); 552 ng_unname(node); 553 bzero(priv, sizeof(*priv)); 554 kfree(priv, M_NETGRAPH); 555 node->private = NULL; 556 ng_unref(node); 557 return (0); 558 } 559 560 /* 561 * Hook disconnection 562 */ 563 static int 564 ng_vjc_disconnect(hook_p hook) 565 { 566 const node_p node = hook->node; 567 const priv_p priv = node->private; 568 569 /* Zero out hook pointer */ 570 if (hook == priv->ip) 571 priv->ip = NULL; 572 else if (hook == priv->vjcomp) 573 priv->vjcomp = NULL; 574 else if (hook == priv->vjuncomp) 575 priv->vjuncomp = NULL; 576 else if (hook == priv->vjip) 577 priv->vjip = NULL; 578 else 579 panic("%s: unknown hook", __func__); 580 581 /* Go away if no hooks left */ 582 if (node->numhooks == 0) 583 ng_rmnode(node); 584 return (0); 585 } 586 587 /************************************************************************ 588 HELPER STUFF 589 ************************************************************************/ 590 591 /* 592 * Pull up the full IP and TCP headers of a packet. If packet is not 593 * a TCP packet, just pull up the IP header. 594 */ 595 static struct mbuf * 596 ng_vjc_pulluphdrs(struct mbuf *m, int knownTCP) 597 { 598 struct ip *ip; 599 struct tcphdr *tcp; 600 int ihlen, thlen; 601 602 if (m->m_len < sizeof(*ip) && (m = m_pullup(m, sizeof(*ip))) == NULL) 603 return (NULL); 604 ip = mtod(m, struct ip *); 605 if (!knownTCP && ip->ip_p != IPPROTO_TCP) 606 return (m); 607 ihlen = ip->ip_hl << 2; 608 if (m->m_len < ihlen + sizeof(*tcp)) { 609 if ((m = m_pullup(m, ihlen + sizeof(*tcp))) == NULL) 610 return (NULL); 611 ip = mtod(m, struct ip *); 612 } 613 tcp = (struct tcphdr *)((u_char *)ip + ihlen); 614 thlen = tcp->th_off << 2; 615 if (m->m_len < ihlen + thlen) 616 m = m_pullup(m, ihlen + thlen); 617 return (m); 618 } 619 620