1 2/* 3 * ng_sample.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 *
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39 * $FreeBSD: head/sys/netgraph/ng_sample.c 132828 2004-07-29 08:05:02Z glebius $
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39 * $FreeBSD: head/sys/netgraph/ng_sample.c 139238 2004-12-23 18:39:13Z rik $ |
40 * $Whistle: ng_sample.c,v 1.13 1999/11/01 09:24:52 julian Exp $ 41 */ 42 43#include <sys/param.h> 44#include <sys/systm.h> 45#include <sys/kernel.h> 46#include <sys/mbuf.h> 47#include <sys/malloc.h> 48#include <sys/ctype.h> 49#include <sys/errno.h> 50#include <sys/syslog.h> 51 52#include <netgraph/ng_message.h> 53#include <netgraph/ng_parse.h> 54#include <netgraph/ng_sample.h> 55#include <netgraph/netgraph.h> 56 57/* If you do complicated mallocs you may want to do this */ 58/* and use it for your mallocs */ 59#ifdef NG_SEPARATE_MALLOC 60MALLOC_DEFINE(M_NETGRAPH_XXX, "netgraph_xxx", "netgraph xxx node "); 61#else 62#define M_NETGRAPH_XXX M_NETGRAPH 63#endif 64 65/* 66 * This section contains the netgraph method declarations for the 67 * sample node. These methods define the netgraph 'type'. 68 */ 69 70static ng_constructor_t ng_xxx_constructor; 71static ng_rcvmsg_t ng_xxx_rcvmsg; 72static ng_shutdown_t ng_xxx_shutdown; 73static ng_newhook_t ng_xxx_newhook; 74static ng_connect_t ng_xxx_connect; 75static ng_rcvdata_t ng_xxx_rcvdata; /* note these are both ng_rcvdata_t */ 76static ng_disconnect_t ng_xxx_disconnect; 77 78/* Parse type for struct ngxxxstat */ 79static const struct ng_parse_struct_field ng_xxx_stat_type_fields[] 80 = NG_XXX_STATS_TYPE_INFO; 81static const struct ng_parse_type ng_xxx_stat_type = { 82 &ng_parse_struct_type, 83 &ng_xxx_stat_type_fields 84}; 85 86/* List of commands and how to convert arguments to/from ASCII */ 87static const struct ng_cmdlist ng_xxx_cmdlist[] = { 88 { 89 NGM_XXX_COOKIE, 90 NGM_XXX_GET_STATUS, 91 "getstatus", 92 NULL, 93 &ng_xxx_stat_type, 94 }, 95 { 96 NGM_XXX_COOKIE, 97 NGM_XXX_SET_FLAG, 98 "setflag", 99 &ng_parse_int32_type, 100 NULL 101 }, 102 { 0 } 103}; 104 105/* Netgraph node type descriptor */ 106static struct ng_type typestruct = { 107 .version = NG_ABI_VERSION, 108 .name = NG_XXX_NODE_TYPE, 109 .constructor = ng_xxx_constructor, 110 .rcvmsg = ng_xxx_rcvmsg, 111 .shutdown = ng_xxx_shutdown, 112 .newhook = ng_xxx_newhook, 113/* .findhook = ng_xxx_findhook, */ 114 .connect = ng_xxx_connect, 115 .rcvdata = ng_xxx_rcvdata, 116 .disconnect = ng_xxx_disconnect, 117 .cmdlist = ng_xxx_cmdlist, 118}; 119NETGRAPH_INIT(xxx, &typestruct); 120 121/* Information we store for each hook on each node */ 122struct XXX_hookinfo { 123 int dlci; /* The DLCI it represents, -1 == downstream */ 124 int channel; /* The channel representing this DLCI */ 125 hook_p hook; 126}; 127 128/* Information we store for each node */ 129struct XXX { 130 struct XXX_hookinfo channel[XXX_NUM_DLCIS]; 131 struct XXX_hookinfo downstream_hook; 132 node_p node; /* back pointer to node */ 133 hook_p debughook; 134 u_int packets_in; /* packets in from downstream */ 135 u_int packets_out; /* packets out towards downstream */ 136 u_int32_t flags; 137}; 138typedef struct XXX *xxx_p; 139 140/* 141 * Allocate the private data structure. The generic node has already 142 * been created. Link them together. We arrive with a reference to the node 143 * i.e. the reference count is incremented for us already. 144 * 145 * If this were a device node than this work would be done in the attach() 146 * routine and the constructor would return EINVAL as you should not be able 147 * to creatednodes that depend on hardware (unless you can add the hardware :) 148 */ 149static int 150ng_xxx_constructor(node_p node) 151{ 152 xxx_p privdata; 153 int i; 154 155 /* Initialize private descriptor */ 156 MALLOC(privdata, xxx_p, sizeof(*privdata), M_NETGRAPH, 157 M_NOWAIT | M_ZERO); 158 if (privdata == NULL) 159 return (ENOMEM); 160 for (i = 0; i < XXX_NUM_DLCIS; i++) { 161 privdata->channel[i].dlci = -2; 162 privdata->channel[i].channel = i; 163 } 164 165 /* Link structs together; this counts as our one reference to *nodep */ 166 NG_NODE_SET_PRIVATE(node, privdata); 167 privdata->node = node; 168 return (0); 169} 170 171/* 172 * Give our ok for a hook to be added... 173 * If we are not running this might kick a device into life. 174 * Possibly decode information out of the hook name. 175 * Add the hook's private info to the hook structure. 176 * (if we had some). In this example, we assume that there is a 177 * an array of structs, called 'channel' in the private info, 178 * one for each active channel. The private 179 * pointer of each hook points to the appropriate XXX_hookinfo struct 180 * so that the source of an input packet is easily identified. 181 * (a dlci is a frame relay channel) 182 */ 183static int 184ng_xxx_newhook(node_p node, hook_p hook, const char *name) 185{ 186 const xxx_p xxxp = NG_NODE_PRIVATE(node); 187 const char *cp; 188 int dlci = 0; 189 int chan; 190 191#if 0 192 /* Possibly start up the device if it's not already going */ 193 if ((xxxp->flags & SCF_RUNNING) == 0) { 194 ng_xxx_start_hardware(xxxp); 195 } 196#endif 197 198 /* Example of how one might use hooks with embedded numbers: All 199 * hooks start with 'dlci' and have a decimal trailing channel 200 * number up to 4 digits Use the leadin defined int he associated .h 201 * file. */ 202 if (strncmp(name, 203 NG_XXX_HOOK_DLCI_LEADIN, strlen(NG_XXX_HOOK_DLCI_LEADIN)) == 0) { 204 char *eptr; 205
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206 cp = name + sizeof(NG_XXX_HOOK_DLCI_LEADIN);
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206 cp = name + strlen(NG_XXX_HOOK_DLCI_LEADIN); |
207 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 208 return (EINVAL); 209 dlci = (int)strtoul(cp, &eptr, 10); 210 if (*eptr != '\0' || dlci < 0 || dlci > 1023) 211 return (EINVAL); 212 213 /* We have a dlci, now either find it, or allocate it */ 214 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 215 if (xxxp->channel[chan].dlci == dlci) 216 break; 217 if (chan == XXX_NUM_DLCIS) { 218 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 219 if (xxxp->channel[chan].dlci != -2) 220 continue; 221 if (chan == XXX_NUM_DLCIS) 222 return (ENOBUFS); 223 } 224 if (xxxp->channel[chan].hook != NULL) 225 return (EADDRINUSE); 226 NG_HOOK_SET_PRIVATE(hook, xxxp->channel + chan); 227 xxxp->channel[chan].hook = hook; 228 return (0); 229 } else if (strcmp(name, NG_XXX_HOOK_DOWNSTREAM) == 0) { 230 /* Example of simple predefined hooks. */ 231 /* do something specific to the downstream connection */ 232 xxxp->downstream_hook.hook = hook; 233 NG_HOOK_SET_PRIVATE(hook, &xxxp->downstream_hook); 234 } else if (strcmp(name, NG_XXX_HOOK_DEBUG) == 0) { 235 /* do something specific to a debug connection */ 236 xxxp->debughook = hook; 237 NG_HOOK_SET_PRIVATE(hook, NULL); 238 } else 239 return (EINVAL); /* not a hook we know about */ 240 return(0); 241} 242 243/* 244 * Get a netgraph control message. 245 * We actually recieve a queue item that has a pointer to the message. 246 * If we free the item, the message will be freed too, unless we remove 247 * it from the item using NGI_GET_MSG(); 248 * The return address is also stored in the item, as an ng_ID_t, 249 * accessible as NGI_RETADDR(item); 250 * Check it is one we understand. If needed, send a response. 251 * We could save the address for an async action later, but don't here. 252 * Always free the message. 253 * The response should be in a malloc'd region that the caller can 'free'. 254 * A response is not required. 255 * Theoretically you could respond defferently to old message types if 256 * the cookie in the header didn't match what we consider to be current 257 * (so that old userland programs could continue to work). 258 */ 259static int 260ng_xxx_rcvmsg(node_p node, item_p item, hook_p lasthook) 261{ 262 const xxx_p xxxp = NG_NODE_PRIVATE(node); 263 struct ng_mesg *resp = NULL; 264 int error = 0; 265 struct ng_mesg *msg; 266 267 NGI_GET_MSG(item, msg); 268 /* Deal with message according to cookie and command */ 269 switch (msg->header.typecookie) { 270 case NGM_XXX_COOKIE: 271 switch (msg->header.cmd) { 272 case NGM_XXX_GET_STATUS: 273 { 274 struct ngxxxstat *stats; 275 276 NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT); 277 if (!resp) { 278 error = ENOMEM; 279 break; 280 } 281 stats = (struct ngxxxstat *) resp->data; 282 stats->packets_in = xxxp->packets_in; 283 stats->packets_out = xxxp->packets_out; 284 break; 285 } 286 case NGM_XXX_SET_FLAG: 287 if (msg->header.arglen != sizeof(u_int32_t)) { 288 error = EINVAL; 289 break; 290 } 291 xxxp->flags = *((u_int32_t *) msg->data); 292 break; 293 default: 294 error = EINVAL; /* unknown command */ 295 break; 296 } 297 break; 298 default: 299 error = EINVAL; /* unknown cookie type */ 300 break; 301 } 302 303 /* Take care of synchronous response, if any */ 304 NG_RESPOND_MSG(error, node, item, resp); 305 /* Free the message and return */ 306 NG_FREE_MSG(msg); 307 return(error); 308} 309 310/* 311 * Receive data, and do something with it. 312 * Actually we receive a queue item which holds the data. 313 * If we free the item it will also free the data unless we have 314 * previously disassociated it using the NGI_GET_M() macro. 315 * Possibly send it out on another link after processing. 316 * Possibly do something different if it comes from different 317 * hooks. The caller will never free m, so if we use up this data or 318 * abort we must free it. 319 * 320 * If we want, we may decide to force this data to be queued and reprocessed 321 * at the netgraph NETISR time. 322 * We would do that by setting the HK_QUEUE flag on our hook. We would do that 323 * in the connect() method. 324 */ 325static int 326ng_xxx_rcvdata(hook_p hook, item_p item ) 327{ 328 const xxx_p xxxp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 329 int chan = -2; 330 int dlci = -2; 331 int error; 332 struct mbuf *m; 333 334 NGI_GET_M(item, m); 335 if (NG_HOOK_PRIVATE(hook)) { 336 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 337 chan = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->channel; 338 if (dlci != -1) { 339 /* If received on a DLCI hook process for this 340 * channel and pass it to the downstream module. 341 * Normally one would add a multiplexing header at 342 * the front here */ 343 /* M_PREPEND(....) ; */ 344 /* mtod(m, xxxxxx)->dlci = dlci; */ 345 NG_FWD_NEW_DATA(error, item, 346 xxxp->downstream_hook.hook, m); 347 xxxp->packets_out++; 348 } else { 349 /* data came from the multiplexed link */ 350 dlci = 1; /* get dlci from header */ 351 /* madjust(....) *//* chop off header */ 352 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 353 if (xxxp->channel[chan].dlci == dlci) 354 break; 355 if (chan == XXX_NUM_DLCIS) { 356 NG_FREE_ITEM(item); 357 NG_FREE_M(m); 358 return (ENETUNREACH); 359 } 360 /* If we were called at splnet, use the following: 361 * NG_SEND_DATA_ONLY(error, otherhook, m); if this 362 * node is running at some SPL other than SPLNET 363 * then you should use instead: error = 364 * ng_queueit(otherhook, m, NULL); m = NULL; 365 * This queues the data using the standard NETISR 366 * system and schedules the data to be picked 367 * up again once the system has moved to SPLNET and 368 * the processing of the data can continue. After 369 * these are run 'm' should be considered 370 * as invalid and NG_SEND_DATA actually zaps them. */ 371 NG_FWD_NEW_DATA(error, item, 372 xxxp->channel[chan].hook, m); 373 xxxp->packets_in++; 374 } 375 } else { 376 /* It's the debug hook, throw it away.. */ 377 if (hook == xxxp->downstream_hook.hook) { 378 NG_FREE_ITEM(item); 379 NG_FREE_M(m); 380 } 381 } 382 return 0; 383} 384 385#if 0 386/* 387 * If this were a device node, the data may have been received in response 388 * to some interrupt. 389 * in which case it would probably look as follows: 390 */ 391devintr() 392{ 393 int error; 394 * here */ 395 396 /* get packet from device and send on */ 397 m = MGET(blah blah) 398 399 NG_SEND_DATA_ONLY(error, xxxp->upstream_hook.hook, m); 400 /* see note above in xxx_rcvdata() */ 401 /* and ng_xxx_connect() */ 402} 403 404#endif /* 0 */ 405 406/* 407 * Do local shutdown processing.. 408 * All our links and the name have already been removed. 409 * If we are a persistant device, we might refuse to go away. 410 * In the case of a persistant node we signal the framework that we 411 * are still in business by clearing the NGF_INVALID bit. However 412 * If we find the NGF_REALLY_DIE bit set, this means that 413 * we REALLY need to die (e.g. hardware removed). 414 * This would have been set using the NG_NODE_REALLY_DIE(node) 415 * macro in some device dependent function (not shown here) before 416 * calling ng_rmnode_self(). 417 */ 418static int 419ng_xxx_shutdown(node_p node) 420{ 421 const xxx_p privdata = NG_NODE_PRIVATE(node); 422 423#ifndef PERSISTANT_NODE 424 NG_NODE_SET_PRIVATE(node, NULL); 425 NG_NODE_UNREF(node); 426 FREE(privdata, M_NETGRAPH); 427#else 428 if (node->nd_flags & NGF_REALLY_DIE) { 429 /* 430 * WE came here because the widget card is being unloaded, 431 * so stop being persistant. 432 * Actually undo all the things we did on creation. 433 */ 434 NG_NODE_SET_PRIVATE(node, NULL); 435 NG_NODE_UNREF(privdata->node); 436 FREE(privdata, M_NETGRAPH); 437 return (0); 438 } 439 NG_NODE_REVIVE(node); /* tell ng_rmnode() we will persist */ 440#endif /* PERSISTANT_NODE */ 441 return (0); 442} 443 444/* 445 * This is called once we've already connected a new hook to the other node. 446 * It gives us a chance to balk at the last minute. 447 */ 448static int 449ng_xxx_connect(hook_p hook) 450{ 451#if 0 452 /* 453 * If we were a driver running at other than splnet then 454 * we should set the QUEUE bit on the edge so that we 455 * will deliver by queing. 456 */ 457 if /*it is the upstream hook */ 458 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 459#endif 460#if 0 461 /* 462 * If for some reason we want incoming date to be queued 463 * by the NETISR system and delivered later we can set the same bit on 464 * OUR hook. (maybe to allow unwinding of the stack) 465 */ 466 467 if (NG_HOOK_PRIVATE(hook)) { 468 int dlci; 469 /* 470 * If it's dlci 1023, requeue it so that it's handled 471 * at a lower priority. This is how a node decides to 472 * defer a data message. 473 */ 474 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 475 if (dlci == 1023) { 476 NG_HOOK_FORCE_QUEUE(hook); 477 } 478#endif 479 /* otherwise be really amiable and just say "YUP that's OK by me! " */ 480 return (0); 481} 482 483/* 484 * Hook disconnection 485 * 486 * For this type, removal of the last link destroys the node 487 */ 488static int 489ng_xxx_disconnect(hook_p hook) 490{ 491 if (NG_HOOK_PRIVATE(hook)) 492 ((struct XXX_hookinfo *) (NG_HOOK_PRIVATE(hook)))->hook = NULL; 493 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 494 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */ 495 ng_rmnode_self(NG_HOOK_NODE(hook)); 496 return (0); 497} 498
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