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