ng_rfc1490.c revision 124506
1 2/* 3 * ng_rfc1490.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: Julian Elischer <julian@freebsd.org> 38 * 39 * $FreeBSD: head/sys/netgraph/ng_rfc1490.c 124506 2004-01-14 00:39:28Z green $ 40 * $Whistle: ng_rfc1490.c,v 1.22 1999/11/01 09:24:52 julian Exp $ 41 */ 42 43/* 44 * This node does RFC 1490 multiplexing. 45 * 46 * NOTE: RFC 1490 is updated by RFC 2427. 47 */ 48 49#include <sys/param.h> 50#include <sys/systm.h> 51#include <sys/errno.h> 52#include <sys/kernel.h> 53#include <sys/malloc.h> 54#include <sys/mbuf.h> 55#include <sys/errno.h> 56#include <sys/socket.h> 57 58#include <net/if.h> 59#include <netinet/in.h> 60#include <netinet/if_ether.h> 61 62#include <netgraph/ng_message.h> 63#include <netgraph/netgraph.h> 64#include <netgraph/ng_rfc1490.h> 65 66/* 67 * DEFINITIONS 68 */ 69 70/* Q.922 stuff -- see RFC 1490 */ 71#define HDLC_UI 0x03 72 73#define NLPID_IP 0xCC 74#define NLPID_PPP 0xCF 75#define NLPID_SNAP 0x80 76#define NLPID_Q933 0x08 77#define NLPID_CLNP 0x81 78#define NLPID_ESIS 0x82 79#define NLPID_ISIS 0x83 80 81/* Node private data */ 82struct ng_rfc1490_private { 83 hook_p downlink; 84 hook_p ppp; 85 hook_p inet; 86 hook_p ethernet; 87}; 88typedef struct ng_rfc1490_private *priv_p; 89 90/* Netgraph node methods */ 91static ng_constructor_t ng_rfc1490_constructor; 92static ng_rcvmsg_t ng_rfc1490_rcvmsg; 93static ng_shutdown_t ng_rfc1490_shutdown; 94static ng_newhook_t ng_rfc1490_newhook; 95static ng_rcvdata_t ng_rfc1490_rcvdata; 96static ng_disconnect_t ng_rfc1490_disconnect; 97 98/* Node type descriptor */ 99static struct ng_type typestruct = { 100 NG_ABI_VERSION, 101 NG_RFC1490_NODE_TYPE, 102 NULL, 103 ng_rfc1490_constructor, 104 ng_rfc1490_rcvmsg, 105 ng_rfc1490_shutdown, 106 ng_rfc1490_newhook, 107 NULL, 108 NULL, 109 ng_rfc1490_rcvdata, 110 ng_rfc1490_disconnect, 111 NULL 112}; 113NETGRAPH_INIT(rfc1490, &typestruct); 114 115/************************************************************************ 116 NETGRAPH NODE STUFF 117 ************************************************************************/ 118 119/* 120 * Node constructor 121 */ 122static int 123ng_rfc1490_constructor(node_p node) 124{ 125 priv_p priv; 126 127 /* Allocate private structure */ 128 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 129 if (priv == NULL) 130 return (ENOMEM); 131 132 NG_NODE_SET_PRIVATE(node, priv); 133 134 /* Done */ 135 return (0); 136} 137 138/* 139 * Give our ok for a hook to be added 140 */ 141static int 142ng_rfc1490_newhook(node_p node, hook_p hook, const char *name) 143{ 144 const priv_p priv = NG_NODE_PRIVATE(node); 145 146 if (!strcmp(name, NG_RFC1490_HOOK_DOWNSTREAM)) { 147 if (priv->downlink) 148 return (EISCONN); 149 priv->downlink = hook; 150 } else if (!strcmp(name, NG_RFC1490_HOOK_PPP)) { 151 if (priv->ppp) 152 return (EISCONN); 153 priv->ppp = hook; 154 } else if (!strcmp(name, NG_RFC1490_HOOK_INET)) { 155 if (priv->inet) 156 return (EISCONN); 157 priv->inet = hook; 158 } else if (!strcmp(name, NG_RFC1490_HOOK_ETHERNET)) { 159 if (priv->ethernet) 160 return (EISCONN); 161 priv->ethernet = hook; 162 } else 163 return (EINVAL); 164 return (0); 165} 166 167/* 168 * Receive a control message. We don't support any special ones. 169 */ 170static int 171ng_rfc1490_rcvmsg(node_p node, item_p item, hook_p lasthook) 172{ 173 NG_FREE_ITEM(item); 174 return (EINVAL); 175} 176 177/* 178 * Receive data on a hook and encapsulate according to RFC 1490. 179 * Only those nodes marked (*) are supported by this routine so far. 180 * 181 * Q.922 control 182 * | 183 * | 184 * -------------------------------------------- 185 * | 0x03 | 186 * UI I Frame 187 * | | 188 * --------------------------------- -------------- 189 * | 0x08 | 0x81 |0xCC |0xCF | 0x00 |..01.... |..10.... 190 * | | | | | 0x80 | | 191 * Q.933 CLNP IP(*) PPP(*) SNAP ISO 8208 ISO 8208 192 * | (rfc1973) | Modulo 8 Modulo 128 193 * | | 194 * -------------------- OUI 195 * | | | 196 * L2 ID L3 ID ------------------------- 197 * | User |00-80-C2 |00-00-00 198 * | specified | | 199 * | 0x70 PID Ethertype 200 * | | | 201 * ------------------- -----------------... ---------- 202 * |0x51 |0x4E | |0x4C |0x7 |0xB | |0x806 | 203 * | | | | | | | | | 204 * 7776 Q.922 Others 802.2 802.3(*) 802.6 Others ARP(*) Others 205 * 206 * 207 */ 208 209#define MAX_ENCAPS_HDR 8 210#define ERROUT(x) do { error = (x); goto done; } while (0) 211#define OUICMP(P,A,B,C) ((P)[0]==(A) && (P)[1]==(B) && (P)[2]==(C)) 212 213static int 214ng_rfc1490_rcvdata(hook_p hook, item_p item) 215{ 216 const node_p node = NG_HOOK_NODE(hook); 217 const priv_p priv = NG_NODE_PRIVATE(node); 218 int error = 0; 219 struct mbuf *m; 220 221 NGI_GET_M(item, m); 222 if (hook == priv->downlink) { 223 const u_char *start; 224 const u_char *ptr; 225 226 if (!m || (m->m_len < MAX_ENCAPS_HDR 227 && !(m = m_pullup(m, MAX_ENCAPS_HDR)))) 228 ERROUT(ENOBUFS); 229 ptr = start = mtod(m, const u_char *); 230 231 /* Must be UI frame */ 232 if (*ptr++ != HDLC_UI) 233 ERROUT(0); 234 235 /* Eat optional zero pad byte */ 236 if (*ptr == 0x00) 237 ptr++; 238 239 /* Multiplex on NLPID */ 240 switch (*ptr++) { 241 case NLPID_SNAP: 242 if (OUICMP(ptr, 0, 0, 0)) { /* It's an ethertype */ 243 u_int16_t etype; 244 245 ptr += 3; 246 etype = ntohs(*((const u_int16_t *)ptr)); 247 ptr += 2; 248 m_adj(m, ptr - start); 249 switch (etype) { 250 case ETHERTYPE_IP: 251 NG_FWD_NEW_DATA(error, item, 252 priv->inet, m); 253 break; 254 case ETHERTYPE_ARP: 255 case ETHERTYPE_REVARP: 256 default: 257 ERROUT(0); 258 } 259 } else if (OUICMP(ptr, 0x00, 0x80, 0xc2)) { 260 /* 802.1 bridging */ 261 ptr += 3; 262 if (*ptr++ != 0x00) 263 ERROUT(0); /* unknown PID octet 0 */ 264 if (*ptr++ != 0x07) 265 ERROUT(0); /* not FCS-less 802.3 */ 266 m_adj(m, ptr - start); 267 NG_FWD_NEW_DATA(error, item, priv->ethernet, m); 268 } else /* Other weird stuff... */ 269 ERROUT(0); 270 break; 271 case NLPID_IP: 272 m_adj(m, ptr - start); 273 NG_FWD_NEW_DATA(error, item, priv->inet, m); 274 break; 275 case NLPID_PPP: 276 m_adj(m, ptr - start); 277 NG_FWD_NEW_DATA(error, item, priv->ppp, m); 278 break; 279 case NLPID_Q933: 280 case NLPID_CLNP: 281 case NLPID_ESIS: 282 case NLPID_ISIS: 283 ERROUT(0); 284 default: /* Try PPP (see RFC 1973) */ 285 ptr--; /* NLPID becomes PPP proto */ 286 if ((*ptr & 0x01) == 0x01) 287 ERROUT(0); 288 m_adj(m, ptr - start); 289 NG_FWD_NEW_DATA(error, item, priv->ppp, m); 290 break; 291 } 292 } else if (hook == priv->ppp) { 293 M_PREPEND(m, 2, M_DONTWAIT); /* Prepend PPP NLPID */ 294 if (!m) 295 ERROUT(ENOBUFS); 296 mtod(m, u_char *)[0] = HDLC_UI; 297 mtod(m, u_char *)[1] = NLPID_PPP; 298 NG_FWD_NEW_DATA(error, item, priv->downlink, m); 299 } else if (hook == priv->inet) { 300 M_PREPEND(m, 2, M_DONTWAIT); /* Prepend IP NLPID */ 301 if (!m) 302 ERROUT(ENOBUFS); 303 mtod(m, u_char *)[0] = HDLC_UI; 304 mtod(m, u_char *)[1] = NLPID_IP; 305 NG_FWD_NEW_DATA(error, item, priv->downlink, m); 306 } else if (hook == priv->ethernet) { 307 M_PREPEND(m, 8, M_DONTWAIT); /* Prepend NLPID, OUI, PID */ 308 if (!m) 309 ERROUT(ENOBUFS); 310 mtod(m, u_char *)[0] = HDLC_UI; 311 mtod(m, u_char *)[1] = 0x00; /* pad */ 312 mtod(m, u_char *)[2] = NLPID_SNAP; 313 mtod(m, u_char *)[3] = 0x00; /* OUI */ 314 mtod(m, u_char *)[4] = 0x80; 315 mtod(m, u_char *)[5] = 0xc2; 316 mtod(m, u_char *)[6] = 0x00; /* PID */ 317 mtod(m, u_char *)[7] = 0x07; 318 NG_FWD_NEW_DATA(error, item, priv->downlink, m); 319 } else 320 panic(__func__); 321 322done: 323 if (item) 324 NG_FREE_ITEM(item); 325 NG_FREE_M(m); 326 return (error); 327} 328 329/* 330 * Nuke node 331 */ 332static int 333ng_rfc1490_shutdown(node_p node) 334{ 335 const priv_p priv = NG_NODE_PRIVATE(node); 336 337 /* Take down netgraph node */ 338 bzero(priv, sizeof(*priv)); 339 FREE(priv, M_NETGRAPH); 340 NG_NODE_SET_PRIVATE(node, NULL); 341 NG_NODE_UNREF(node); /* let the node escape */ 342 return (0); 343} 344 345/* 346 * Hook disconnection 347 */ 348static int 349ng_rfc1490_disconnect(hook_p hook) 350{ 351 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 352 353 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 354 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 355 ng_rmnode_self(NG_HOOK_NODE(hook)); 356 else if (hook == priv->downlink) 357 priv->downlink = NULL; 358 else if (hook == priv->inet) 359 priv->inet = NULL; 360 else if (hook == priv->ppp) 361 priv->ppp = NULL; 362 else if (hook == priv->ethernet) 363 priv->ethernet = NULL; 364 else 365 panic(__func__); 366 return (0); 367} 368 369