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: src/sys/netgraph/ng_rfc1490.c,v 1.6.2.4 2002/07/02 22:17:18 archie Exp $ 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 "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 }; 87 typedef struct ng_rfc1490_private *priv_p; 88 89 /* Netgraph node methods */ 90 static ng_constructor_t ng_rfc1490_constructor; 91 static ng_rcvmsg_t ng_rfc1490_rcvmsg; 92 static ng_shutdown_t ng_rfc1490_rmnode; 93 static ng_newhook_t ng_rfc1490_newhook; 94 static ng_rcvdata_t ng_rfc1490_rcvdata; 95 static ng_disconnect_t ng_rfc1490_disconnect; 96 97 /* Node type descriptor */ 98 static struct ng_type typestruct = { 99 NG_VERSION, 100 NG_RFC1490_NODE_TYPE, 101 NULL, 102 ng_rfc1490_constructor, 103 ng_rfc1490_rcvmsg, 104 ng_rfc1490_rmnode, 105 ng_rfc1490_newhook, 106 NULL, 107 NULL, 108 ng_rfc1490_rcvdata, 109 ng_rfc1490_rcvdata, 110 ng_rfc1490_disconnect, 111 NULL 112 }; 113 NETGRAPH_INIT(rfc1490, &typestruct); 114 115 /************************************************************************ 116 NETGRAPH NODE STUFF 117 ************************************************************************/ 118 119 /* 120 * Node constructor 121 */ 122 static int 123 ng_rfc1490_constructor(node_p *nodep) 124 { 125 priv_p priv; 126 int error; 127 128 /* Allocate private structure */ 129 priv = kmalloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 130 if (priv == NULL) 131 return (ENOMEM); 132 133 /* Call generic node constructor */ 134 if ((error = ng_make_node_common(&typestruct, nodep))) { 135 kfree(priv, M_NETGRAPH); 136 return (error); 137 } 138 (*nodep)->private = priv; 139 140 /* Done */ 141 return (0); 142 } 143 144 /* 145 * Give our ok for a hook to be added 146 */ 147 static int 148 ng_rfc1490_newhook(node_p node, hook_p hook, const char *name) 149 { 150 const priv_p priv = node->private; 151 152 if (!strcmp(name, NG_RFC1490_HOOK_DOWNSTREAM)) { 153 if (priv->downlink) 154 return (EISCONN); 155 priv->downlink = hook; 156 } else if (!strcmp(name, NG_RFC1490_HOOK_PPP)) { 157 if (priv->ppp) 158 return (EISCONN); 159 priv->ppp = hook; 160 } else if (!strcmp(name, NG_RFC1490_HOOK_INET)) { 161 if (priv->inet) 162 return (EISCONN); 163 priv->inet = hook; 164 } else 165 return (EINVAL); 166 return (0); 167 } 168 169 /* 170 * Receive a control message. We don't support any special ones. 171 */ 172 static int 173 ng_rfc1490_rcvmsg(node_p node, struct ng_mesg *msg, 174 const char *raddr, struct ng_mesg **rp) 175 { 176 kfree(msg, M_NETGRAPH); 177 return (EINVAL); 178 } 179 180 /* 181 * Receive data on a hook and encapsulate according to RFC 1490. 182 * Only those nodes marked (*) are supported by this routine so far. 183 * 184 * Q.922 control 185 * | 186 * | 187 * -------------------------------------------- 188 * | 0x03 | 189 * UI I Frame 190 * | | 191 * --------------------------------- -------------- 192 * | 0x08 | 0x81 |0xCC |0xCF | 0x00 |..01.... |..10.... 193 * | | | | | 0x80 | | 194 * Q.933 CLNP IP(*) PPP(*) SNAP ISO 8208 ISO 8208 195 * | (rfc1973) | Modulo 8 Modulo 128 196 * | | 197 * -------------------- OUI 198 * | | | 199 * L2 ID L3 ID ------------------------- 200 * | User |00-80-C2 |00-00-00 201 * | specified | | 202 * | 0x70 PID Ethertype 203 * | | | 204 * ------------------- --------------... ---------- 205 * |0x51 |0x4E | |0x4C |0x1 |0xB | |0x806 | 206 * | | | | | | | | | 207 * 7776 Q.922 Others 802.2 802.3 802.6 Others ARP(*) Others 208 * 209 * 210 */ 211 212 #define MAX_ENCAPS_HDR 8 213 #define ERROUT(x) do { error = (x); goto done; } while (0) 214 #define OUICMP(P,A,B,C) ((P)[0]==(A) && (P)[1]==(B) && (P)[2]==(C)) 215 216 static int 217 ng_rfc1490_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 218 { 219 const node_p node = hook->node; 220 const priv_p priv = node->private; 221 int error = 0; 222 223 if (hook == priv->downlink) { 224 const u_char *start; 225 const u_char *ptr; 226 227 if (!m || (m->m_len < MAX_ENCAPS_HDR 228 && !(m = m_pullup(m, MAX_ENCAPS_HDR)))) 229 ERROUT(ENOBUFS); 230 ptr = start = mtod(m, const u_char *); 231 232 /* Must be UI frame */ 233 if (*ptr++ != HDLC_UI) 234 ERROUT(0); 235 236 /* Eat optional zero pad byte */ 237 if (*ptr == 0x00) 238 ptr++; 239 240 /* Multiplex on NLPID */ 241 switch (*ptr++) { 242 case NLPID_SNAP: 243 if (OUICMP(ptr, 0, 0, 0)) { /* It's an ethertype */ 244 u_int16_t etype; 245 246 ptr += 3; 247 etype = ntohs(*((const u_int16_t *)ptr)); 248 ptr += 2; 249 m_adj(m, ptr - start); 250 switch (etype) { 251 case ETHERTYPE_IP: 252 NG_SEND_DATA(error, 253 priv->inet, m, meta); 254 break; 255 case ETHERTYPE_ARP: 256 case ETHERTYPE_REVARP: 257 default: 258 ERROUT(0); 259 } 260 } else if (OUICMP(ptr, 0x00, 0x80, 0xc2)) /* 802.1 bridging */ 261 ERROUT(0); 262 else /* Other weird stuff... */ 263 ERROUT(0); 264 break; 265 case NLPID_IP: 266 m_adj(m, ptr - start); 267 NG_SEND_DATA(error, priv->inet, m, meta); 268 break; 269 case NLPID_PPP: 270 m_adj(m, ptr - start); 271 NG_SEND_DATA(error, priv->ppp, m, meta); 272 break; 273 case NLPID_Q933: 274 case NLPID_CLNP: 275 case NLPID_ESIS: 276 case NLPID_ISIS: 277 ERROUT(0); 278 default: /* Try PPP (see RFC 1973) */ 279 ptr--; /* NLPID becomes PPP proto */ 280 if ((*ptr & 0x01) == 0x01) 281 ERROUT(0); 282 m_adj(m, ptr - start); 283 NG_SEND_DATA(error, priv->ppp, m, meta); 284 break; 285 } 286 } else if (hook == priv->ppp) { 287 M_PREPEND(m, 2, MB_DONTWAIT); /* Prepend PPP NLPID */ 288 if (!m) 289 ERROUT(ENOBUFS); 290 mtod(m, u_char *)[0] = HDLC_UI; 291 mtod(m, u_char *)[1] = NLPID_PPP; 292 NG_SEND_DATA(error, priv->downlink, m, meta); 293 } else if (hook == priv->inet) { 294 M_PREPEND(m, 2, MB_DONTWAIT); /* Prepend IP NLPID */ 295 if (!m) 296 ERROUT(ENOBUFS); 297 mtod(m, u_char *)[0] = HDLC_UI; 298 mtod(m, u_char *)[1] = NLPID_IP; 299 NG_SEND_DATA(error, priv->downlink, m, meta); 300 } else 301 panic(__func__); 302 303 done: 304 NG_FREE_DATA(m, meta); 305 return (error); 306 } 307 308 /* 309 * Nuke node 310 */ 311 static int 312 ng_rfc1490_rmnode(node_p node) 313 { 314 const priv_p priv = node->private; 315 316 /* Take down netgraph node */ 317 node->flags |= NG_INVALID; 318 ng_cutlinks(node); 319 ng_unname(node); 320 bzero(priv, sizeof(*priv)); 321 node->private = NULL; 322 kfree(priv, M_NETGRAPH); 323 ng_unref(node); /* let the node escape */ 324 return (0); 325 } 326 327 /* 328 * Hook disconnection 329 */ 330 static int 331 ng_rfc1490_disconnect(hook_p hook) 332 { 333 const priv_p priv = hook->node->private; 334 335 if (hook->node->numhooks == 0) 336 ng_rmnode(hook->node); 337 else if (hook == priv->downlink) 338 priv->downlink = NULL; 339 else if (hook == priv->inet) 340 priv->inet = NULL; 341 else if (hook == priv->ppp) 342 priv->ppp = NULL; 343 else 344 panic(__func__); 345 return (0); 346 } 347 348