1/* 2 * ng_sample.c 3 */ 4 5/*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Author: Julian Elischer <julian@freebsd.org> 39 * $Whistle: ng_sample.c,v 1.13 1999/11/01 09:24:52 julian Exp $ 40 */ 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/kernel.h> 45#include <sys/mbuf.h> 46#include <sys/malloc.h> 47#include <sys/ctype.h> 48#include <sys/errno.h> 49#include <sys/syslog.h> 50 51#include <netgraph/ng_message.h> 52#include <netgraph/ng_parse.h> 53#include <netgraph/ng_sample.h> 54#include <netgraph/netgraph.h> 55 56/* If you do complicated mallocs you may want to do this */ 57/* and use it for your mallocs */ 58#ifdef NG_SEPARATE_MALLOC 59static MALLOC_DEFINE(M_NETGRAPH_XXX, "netgraph_xxx", "netgraph xxx node"); 60#else 61#define M_NETGRAPH_XXX M_NETGRAPH 62#endif 63 64/* 65 * This section contains the netgraph method declarations for the 66 * sample node. These methods define the netgraph 'type'. 67 */ 68 69static ng_constructor_t ng_xxx_constructor; 70static ng_rcvmsg_t ng_xxx_rcvmsg; 71static ng_shutdown_t ng_xxx_shutdown; 72static ng_newhook_t ng_xxx_newhook; 73static ng_connect_t ng_xxx_connect; 74static ng_rcvdata_t ng_xxx_rcvdata; 75static ng_disconnect_t ng_xxx_disconnect; 76 77/* Parse type for struct ngxxxstat */ 78static const struct ng_parse_struct_field ng_xxx_stat_type_fields[] 79 = NG_XXX_STATS_TYPE_INFO; 80static const struct ng_parse_type ng_xxx_stat_type = { 81 &ng_parse_struct_type, 82 &ng_xxx_stat_type_fields 83}; 84 85/* List of commands and how to convert arguments to/from ASCII */ 86static const struct ng_cmdlist ng_xxx_cmdlist[] = { 87 { 88 NGM_XXX_COOKIE, 89 NGM_XXX_GET_STATUS, 90 "getstatus", 91 NULL, 92 &ng_xxx_stat_type, 93 }, 94 { 95 NGM_XXX_COOKIE, 96 NGM_XXX_SET_FLAG, 97 "setflag", 98 &ng_parse_int32_type, 99 NULL 100 }, 101 { 0 } 102}; 103 104/* Netgraph node type descriptor */ 105static struct ng_type typestruct = { 106 .version = NG_ABI_VERSION, 107 .name = NG_XXX_NODE_TYPE, 108 .constructor = ng_xxx_constructor, 109 .rcvmsg = ng_xxx_rcvmsg, 110 .shutdown = ng_xxx_shutdown, 111 .newhook = ng_xxx_newhook, 112/* .findhook = ng_xxx_findhook, */ 113 .connect = ng_xxx_connect, 114 .rcvdata = ng_xxx_rcvdata, 115 .disconnect = ng_xxx_disconnect, 116 .cmdlist = ng_xxx_cmdlist, 117}; 118NETGRAPH_INIT(xxx, &typestruct); 119 120/* Information we store for each hook on each node */ 121struct XXX_hookinfo { 122 int dlci; /* The DLCI it represents, -1 == downstream */ 123 int channel; /* The channel representing this DLCI */ 124 hook_p hook; 125}; 126 127/* Information we store for each node */ 128struct XXX { 129 struct XXX_hookinfo channel[XXX_NUM_DLCIS]; 130 struct XXX_hookinfo downstream_hook; 131 node_p node; /* back pointer to node */ 132 hook_p debughook; 133 u_int packets_in; /* packets in from downstream */ 134 u_int packets_out; /* packets out towards downstream */ 135 u_int32_t flags; 136}; 137typedef struct XXX *xxx_p; 138 139/* 140 * Allocate the private data structure. The generic node has already 141 * been created. Link them together. We arrive with a reference to the node 142 * i.e. the reference count is incremented for us already. 143 * 144 * If this were a device node than this work would be done in the attach() 145 * routine and the constructor would return EINVAL as you should not be able 146 * to creatednodes that depend on hardware (unless you can add the hardware :) 147 */ 148static int 149ng_xxx_constructor(node_p node) 150{ 151 xxx_p privdata; 152 int i; 153 154 /* Initialize private descriptor */ 155 privdata = malloc(sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO); 156 for (i = 0; i < XXX_NUM_DLCIS; i++) { 157 privdata->channel[i].dlci = -2; 158 privdata->channel[i].channel = i; 159 } 160 161 /* Link structs together; this counts as our one reference to *nodep */ 162 NG_NODE_SET_PRIVATE(node, privdata); 163 privdata->node = node; 164 return (0); 165} 166 167/* 168 * Give our ok for a hook to be added... 169 * If we are not running this might kick a device into life. 170 * Possibly decode information out of the hook name. 171 * Add the hook's private info to the hook structure. 172 * (if we had some). In this example, we assume that there is a 173 * an array of structs, called 'channel' in the private info, 174 * one for each active channel. The private 175 * pointer of each hook points to the appropriate XXX_hookinfo struct 176 * so that the source of an input packet is easily identified. 177 * (a dlci is a frame relay channel) 178 */ 179static int 180ng_xxx_newhook(node_p node, hook_p hook, const char *name) 181{ 182 const xxx_p xxxp = NG_NODE_PRIVATE(node); 183 const char *cp; 184 int dlci = 0; 185 int chan; 186 187#if 0 188 /* Possibly start up the device if it's not already going */ 189 if ((xxxp->flags & SCF_RUNNING) == 0) { 190 ng_xxx_start_hardware(xxxp); 191 } 192#endif 193 194 /* Example of how one might use hooks with embedded numbers: All 195 * hooks start with 'dlci' and have a decimal trailing channel 196 * number up to 4 digits Use the leadin defined int he associated .h 197 * file. */ 198 if (strncmp(name, 199 NG_XXX_HOOK_DLCI_LEADIN, strlen(NG_XXX_HOOK_DLCI_LEADIN)) == 0) { 200 char *eptr; 201 202 cp = name + strlen(NG_XXX_HOOK_DLCI_LEADIN); 203 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 204 return (EINVAL); 205 dlci = (int)strtoul(cp, &eptr, 10); 206 if (*eptr != '\0' || dlci < 0 || dlci > 1023) 207 return (EINVAL); 208 209 /* We have a dlci, now either find it, or allocate it */ 210 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 211 if (xxxp->channel[chan].dlci == dlci) 212 break; 213 if (chan == XXX_NUM_DLCIS) { 214 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 215 if (xxxp->channel[chan].dlci == -2) 216 break; 217 if (chan == XXX_NUM_DLCIS) 218 return (ENOBUFS); 219 xxxp->channel[chan].dlci = dlci; 220 } 221 if (xxxp->channel[chan].hook != NULL) 222 return (EADDRINUSE); 223 NG_HOOK_SET_PRIVATE(hook, xxxp->channel + chan); 224 xxxp->channel[chan].hook = hook; 225 return (0); 226 } else if (strcmp(name, NG_XXX_HOOK_DOWNSTREAM) == 0) { 227 /* Example of simple predefined hooks. */ 228 /* do something specific to the downstream connection */ 229 xxxp->downstream_hook.hook = hook; 230 NG_HOOK_SET_PRIVATE(hook, &xxxp->downstream_hook); 231 } else if (strcmp(name, NG_XXX_HOOK_DEBUG) == 0) { 232 /* do something specific to a debug connection */ 233 xxxp->debughook = hook; 234 NG_HOOK_SET_PRIVATE(hook, NULL); 235 } else 236 return (EINVAL); /* not a hook we know about */ 237 return(0); 238} 239 240/* 241 * Get a netgraph control message. 242 * We actually receive a queue item that has a pointer to the message. 243 * If we free the item, the message will be freed too, unless we remove 244 * it from the item using NGI_GET_MSG(); 245 * The return address is also stored in the item, as an ng_ID_t, 246 * accessible as NGI_RETADDR(item); 247 * Check it is one we understand. If needed, send a response. 248 * We could save the address for an async action later, but don't here. 249 * Always free the message. 250 * The response should be in a malloc'd region that the caller can 'free'. 251 * A response is not required. 252 * Theoretically you could respond defferently to old message types if 253 * the cookie in the header didn't match what we consider to be current 254 * (so that old userland programs could continue to work). 255 */ 256static int 257ng_xxx_rcvmsg(node_p node, item_p item, hook_p lasthook) 258{ 259 const xxx_p xxxp = NG_NODE_PRIVATE(node); 260 struct ng_mesg *resp = NULL; 261 int error = 0; 262 struct ng_mesg *msg; 263 264 NGI_GET_MSG(item, msg); 265 /* Deal with message according to cookie and command */ 266 switch (msg->header.typecookie) { 267 case NGM_XXX_COOKIE: 268 switch (msg->header.cmd) { 269 case NGM_XXX_GET_STATUS: 270 { 271 struct ngxxxstat *stats; 272 273 NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT); 274 if (!resp) { 275 error = ENOMEM; 276 break; 277 } 278 stats = (struct ngxxxstat *) resp->data; 279 stats->packets_in = xxxp->packets_in; 280 stats->packets_out = xxxp->packets_out; 281 break; 282 } 283 case NGM_XXX_SET_FLAG: 284 if (msg->header.arglen != sizeof(u_int32_t)) { 285 error = EINVAL; 286 break; 287 } 288 xxxp->flags = *((u_int32_t *) msg->data); 289 break; 290 default: 291 error = EINVAL; /* unknown command */ 292 break; 293 } 294 break; 295 default: 296 error = EINVAL; /* unknown cookie type */ 297 break; 298 } 299 300 /* Take care of synchronous response, if any */ 301 NG_RESPOND_MSG(error, node, item, resp); 302 /* Free the message and return */ 303 NG_FREE_MSG(msg); 304 return(error); 305} 306 307/* 308 * Receive data, and do something with it. 309 * Actually we receive a queue item which holds the data. 310 * If we free the item it will also free the data unless we have 311 * previously disassociated it using the NGI_GET_M() macro. 312 * Possibly send it out on another link after processing. 313 * Possibly do something different if it comes from different 314 * hooks. The caller will never free m, so if we use up this data or 315 * abort we must free it. 316 * 317 * If we want, we may decide to force this data to be queued and reprocessed 318 * at the netgraph NETISR time. 319 * We would do that by setting the HK_QUEUE flag on our hook. We would do that 320 * in the connect() method. 321 */ 322static int 323ng_xxx_rcvdata(hook_p hook, item_p item ) 324{ 325 const xxx_p xxxp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 326 int chan = -2; 327 int dlci = -2; 328 int error; 329 struct mbuf *m; 330 331 NGI_GET_M(item, m); 332 if (NG_HOOK_PRIVATE(hook)) { 333 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 334 chan = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->channel; 335 if (dlci != -1) { 336 /* If received on a DLCI hook process for this 337 * channel and pass it to the downstream module. 338 * Normally one would add a multiplexing header at 339 * the front here */ 340 /* M_PREPEND(....) ; */ 341 /* mtod(m, xxxxxx)->dlci = dlci; */ 342 NG_FWD_NEW_DATA(error, item, 343 xxxp->downstream_hook.hook, m); 344 xxxp->packets_out++; 345 } else { 346 /* data came from the multiplexed link */ 347 dlci = 1; /* get dlci from header */ 348 /* madjust(....) *//* chop off header */ 349 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 350 if (xxxp->channel[chan].dlci == dlci) 351 break; 352 if (chan == XXX_NUM_DLCIS) { 353 NG_FREE_ITEM(item); 354 NG_FREE_M(m); 355 return (ENETUNREACH); 356 } 357 /* After this are run 'm' should be considered 358 * as invalid. */ 359 NG_FWD_NEW_DATA(error, item, 360 xxxp->channel[chan].hook, m); 361 xxxp->packets_in++; 362 } 363 } else { 364 /* It's the debug hook, throw it away.. */ 365 if (hook == xxxp->downstream_hook.hook) { 366 NG_FREE_ITEM(item); 367 NG_FREE_M(m); 368 } 369 } 370 return 0; 371} 372 373#if 0 374/* 375 * If this were a device node, the data may have been received in response 376 * to some interrupt. 377 * in which case it would probably look as follows: 378 */ 379devintr() 380{ 381 int error; 382 383 /* get packet from device and send on */ 384 m = MGET(blah blah) 385 386 NG_SEND_DATA_ONLY(error, xxxp->upstream_hook.hook, m); 387 /* see note above in xxx_rcvdata() */ 388 /* and ng_xxx_connect() */ 389} 390 391#endif /* 0 */ 392 393/* 394 * Do local shutdown processing.. 395 * All our links and the name have already been removed. 396 * If we are a persistent device, we might refuse to go away. 397 * In the case of a persistent node we signal the framework that we 398 * are still in business by clearing the NGF_INVALID bit. However 399 * If we find the NGF_REALLY_DIE bit set, this means that 400 * we REALLY need to die (e.g. hardware removed). 401 * This would have been set using the NG_NODE_REALLY_DIE(node) 402 * macro in some device dependent function (not shown here) before 403 * calling ng_rmnode_self(). 404 */ 405static int 406ng_xxx_shutdown(node_p node) 407{ 408 const xxx_p privdata = NG_NODE_PRIVATE(node); 409 410#ifndef PERSISTANT_NODE 411 NG_NODE_SET_PRIVATE(node, NULL); 412 NG_NODE_UNREF(node); 413 free(privdata, M_NETGRAPH); 414#else 415 if (node->nd_flags & NGF_REALLY_DIE) { 416 /* 417 * WE came here because the widget card is being unloaded, 418 * so stop being persistent. 419 * Actually undo all the things we did on creation. 420 */ 421 NG_NODE_SET_PRIVATE(node, NULL); 422 NG_NODE_UNREF(privdata->node); 423 free(privdata, M_NETGRAPH); 424 return (0); 425 } 426 NG_NODE_REVIVE(node); /* tell ng_rmnode() we will persist */ 427#endif /* PERSISTANT_NODE */ 428 return (0); 429} 430 431/* 432 * This is called once we've already connected a new hook to the other node. 433 * It gives us a chance to balk at the last minute. 434 */ 435static int 436ng_xxx_connect(hook_p hook) 437{ 438#if 0 439 /* 440 * If we were a driver running at other than splnet then 441 * we should set the QUEUE bit on the edge so that we 442 * will deliver by queing. 443 */ 444 if /*it is the upstream hook */ 445 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 446#endif 447#if 0 448 /* 449 * If for some reason we want incoming date to be queued 450 * by the NETISR system and delivered later we can set the same bit on 451 * OUR hook. (maybe to allow unwinding of the stack) 452 */ 453 454 if (NG_HOOK_PRIVATE(hook)) { 455 int dlci; 456 /* 457 * If it's dlci 1023, requeue it so that it's handled 458 * at a lower priority. This is how a node decides to 459 * defer a data message. 460 */ 461 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 462 if (dlci == 1023) { 463 NG_HOOK_FORCE_QUEUE(hook); 464 } 465#endif 466 /* otherwise be really amiable and just say "YUP that's OK by me! " */ 467 return (0); 468} 469 470/* 471 * Hook disconnection 472 * 473 * For this type, removal of the last link destroys the node 474 */ 475static int 476ng_xxx_disconnect(hook_p hook) 477{ 478 if (NG_HOOK_PRIVATE(hook)) 479 ((struct XXX_hookinfo *) (NG_HOOK_PRIVATE(hook)))->hook = NULL; 480 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 481 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */ 482 ng_rmnode_self(NG_HOOK_NODE(hook)); 483 return (0); 484} 485