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 * 40 * $FreeBSD: src/sys/netgraph/ng_sample.c,v 1.30 2005/02/06 19:24:59 glebius Exp $ 41 * $DragonFly: src/sys/netgraph7/ng_sample.c,v 1.2 2008/06/26 23:05:35 dillon Exp $ 42 * $Whistle: ng_sample.c,v 1.13 1999/11/01 09:24:52 julian Exp $ 43 */ 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/mbuf.h> 49 #include <sys/malloc.h> 50 #include <sys/ctype.h> 51 #include <sys/errno.h> 52 #include <sys/syslog.h> 53 54 #include "ng_message.h" 55 #include "ng_parse.h" 56 #include "ng_sample.h" 57 #include "netgraph.h" 58 59 /* If you do complicated mallocs you may want to do this */ 60 /* and use it for your mallocs */ 61 #ifdef NG_SEPARATE_MALLOC 62 MALLOC_DEFINE(M_NETGRAPH_XXX, "netgraph_xxx", "netgraph xxx node "); 63 #else 64 #define M_NETGRAPH_XXX M_NETGRAPH 65 #endif 66 67 /* 68 * This section contains the netgraph method declarations for the 69 * sample node. These methods define the netgraph 'type'. 70 */ 71 72 static ng_constructor_t ng_xxx_constructor; 73 static ng_rcvmsg_t ng_xxx_rcvmsg; 74 static ng_shutdown_t ng_xxx_shutdown; 75 static ng_newhook_t ng_xxx_newhook; 76 static ng_connect_t ng_xxx_connect; 77 static ng_rcvdata_t ng_xxx_rcvdata; 78 static ng_disconnect_t ng_xxx_disconnect; 79 80 /* Parse type for struct ngxxxstat */ 81 static const struct ng_parse_struct_field ng_xxx_stat_type_fields[] 82 = NG_XXX_STATS_TYPE_INFO; 83 static const struct ng_parse_type ng_xxx_stat_type = { 84 &ng_parse_struct_type, 85 &ng_xxx_stat_type_fields 86 }; 87 88 /* List of commands and how to convert arguments to/from ASCII */ 89 static const struct ng_cmdlist ng_xxx_cmdlist[] = { 90 { 91 NGM_XXX_COOKIE, 92 NGM_XXX_GET_STATUS, 93 "getstatus", 94 NULL, 95 &ng_xxx_stat_type, 96 }, 97 { 98 NGM_XXX_COOKIE, 99 NGM_XXX_SET_FLAG, 100 "setflag", 101 &ng_parse_int32_type, 102 NULL 103 }, 104 { 0 } 105 }; 106 107 /* Netgraph node type descriptor */ 108 static struct ng_type typestruct = { 109 .version = NG_ABI_VERSION, 110 .name = NG_XXX_NODE_TYPE, 111 .constructor = ng_xxx_constructor, 112 .rcvmsg = ng_xxx_rcvmsg, 113 .shutdown = ng_xxx_shutdown, 114 .newhook = ng_xxx_newhook, 115 /* .findhook = ng_xxx_findhook, */ 116 .connect = ng_xxx_connect, 117 .rcvdata = ng_xxx_rcvdata, 118 .disconnect = ng_xxx_disconnect, 119 .cmdlist = ng_xxx_cmdlist, 120 }; 121 NETGRAPH_INIT(xxx, &typestruct); 122 123 /* Information we store for each hook on each node */ 124 struct XXX_hookinfo { 125 int dlci; /* The DLCI it represents, -1 == downstream */ 126 int channel; /* The channel representing this DLCI */ 127 hook_p hook; 128 }; 129 130 /* Information we store for each node */ 131 struct XXX { 132 struct XXX_hookinfo channel[XXX_NUM_DLCIS]; 133 struct XXX_hookinfo downstream_hook; 134 node_p node; /* back pointer to node */ 135 hook_p debughook; 136 u_int packets_in; /* packets in from downstream */ 137 u_int packets_out; /* packets out towards downstream */ 138 u_int32_t flags; 139 }; 140 typedef struct XXX *xxx_p; 141 142 /* 143 * Allocate the private data structure. The generic node has already 144 * been created. Link them together. We arrive with a reference to the node 145 * i.e. the reference count is incremented for us already. 146 * 147 * If this were a device node than this work would be done in the attach() 148 * routine and the constructor would return EINVAL as you should not be able 149 * to creatednodes that depend on hardware (unless you can add the hardware :) 150 */ 151 static int 152 ng_xxx_constructor(node_p node) 153 { 154 xxx_p privdata; 155 int i; 156 157 /* Initialize private descriptor */ 158 privdata = kmalloc(sizeof(*privdata), M_NETGRAPH, 159 M_WAITOK | M_NULLOK | M_ZERO); 160 if (privdata == NULL) 161 return (ENOMEM); 162 for (i = 0; i < XXX_NUM_DLCIS; i++) { 163 privdata->channel[i].dlci = -2; 164 privdata->channel[i].channel = i; 165 } 166 167 /* Link structs together; this counts as our one reference to *nodep */ 168 NG_NODE_SET_PRIVATE(node, privdata); 169 privdata->node = node; 170 return (0); 171 } 172 173 /* 174 * Give our ok for a hook to be added... 175 * If we are not running this might kick a device into life. 176 * Possibly decode information out of the hook name. 177 * Add the hook's private info to the hook structure. 178 * (if we had some). In this example, we assume that there is a 179 * an array of structs, called 'channel' in the private info, 180 * one for each active channel. The private 181 * pointer of each hook points to the appropriate XXX_hookinfo struct 182 * so that the source of an input packet is easily identified. 183 * (a dlci is a frame relay channel) 184 */ 185 static int 186 ng_xxx_newhook(node_p node, hook_p hook, const char *name) 187 { 188 const xxx_p xxxp = NG_NODE_PRIVATE(node); 189 const char *cp; 190 int dlci = 0; 191 int chan; 192 193 #if 0 194 /* Possibly start up the device if it's not already going */ 195 if ((xxxp->flags & SCF_RUNNING) == 0) { 196 ng_xxx_start_hardware(xxxp); 197 } 198 #endif 199 200 /* Example of how one might use hooks with embedded numbers: All 201 * hooks start with 'dlci' and have a decimal trailing channel 202 * number up to 4 digits Use the leadin defined int he associated .h 203 * file. */ 204 if (strncmp(name, 205 NG_XXX_HOOK_DLCI_LEADIN, strlen(NG_XXX_HOOK_DLCI_LEADIN)) == 0) { 206 char *eptr; 207 208 cp = name + strlen(NG_XXX_HOOK_DLCI_LEADIN); 209 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0')) 210 return (EINVAL); 211 dlci = (int)strtoul(cp, &eptr, 10); 212 if (*eptr != '\0' || dlci < 0 || dlci > 1023) 213 return (EINVAL); 214 215 /* We have a dlci, now either find it, or allocate it */ 216 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 217 if (xxxp->channel[chan].dlci == dlci) 218 break; 219 if (chan == XXX_NUM_DLCIS) { 220 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 221 if (xxxp->channel[chan].dlci == -2) 222 break; 223 if (chan == XXX_NUM_DLCIS) 224 return (ENOBUFS); 225 xxxp->channel[chan].dlci = dlci; 226 } 227 if (xxxp->channel[chan].hook != NULL) 228 return (EADDRINUSE); 229 NG_HOOK_SET_PRIVATE(hook, xxxp->channel + chan); 230 xxxp->channel[chan].hook = hook; 231 return (0); 232 } else if (strcmp(name, NG_XXX_HOOK_DOWNSTREAM) == 0) { 233 /* Example of simple predefined hooks. */ 234 /* do something specific to the downstream connection */ 235 xxxp->downstream_hook.hook = hook; 236 NG_HOOK_SET_PRIVATE(hook, &xxxp->downstream_hook); 237 } else if (strcmp(name, NG_XXX_HOOK_DEBUG) == 0) { 238 /* do something specific to a debug connection */ 239 xxxp->debughook = hook; 240 NG_HOOK_SET_PRIVATE(hook, NULL); 241 } else 242 return (EINVAL); /* not a hook we know about */ 243 return(0); 244 } 245 246 /* 247 * Get a netgraph control message. 248 * We actually recieve a queue item that has a pointer to the message. 249 * If we free the item, the message will be freed too, unless we remove 250 * it from the item using NGI_GET_MSG(); 251 * The return address is also stored in the item, as an ng_ID_t, 252 * accessible as NGI_RETADDR(item); 253 * Check it is one we understand. If needed, send a response. 254 * We could save the address for an async action later, but don't here. 255 * Always free the message. 256 * The response should be in a malloc'd region that the caller can 'free'. 257 * A response is not required. 258 * Theoretically you could respond defferently to old message types if 259 * the cookie in the header didn't match what we consider to be current 260 * (so that old userland programs could continue to work). 261 */ 262 static int 263 ng_xxx_rcvmsg(node_p node, item_p item, hook_p lasthook) 264 { 265 const xxx_p xxxp = NG_NODE_PRIVATE(node); 266 struct ng_mesg *resp = NULL; 267 int error = 0; 268 struct ng_mesg *msg; 269 270 NGI_GET_MSG(item, msg); 271 /* Deal with message according to cookie and command */ 272 switch (msg->header.typecookie) { 273 case NGM_XXX_COOKIE: 274 switch (msg->header.cmd) { 275 case NGM_XXX_GET_STATUS: 276 { 277 struct ngxxxstat *stats; 278 279 NG_MKRESPONSE(resp, msg, sizeof(*stats), M_WAITOK | M_NULLOK); 280 if (!resp) { 281 error = ENOMEM; 282 break; 283 } 284 stats = (struct ngxxxstat *) resp->data; 285 stats->packets_in = xxxp->packets_in; 286 stats->packets_out = xxxp->packets_out; 287 break; 288 } 289 case NGM_XXX_SET_FLAG: 290 if (msg->header.arglen != sizeof(u_int32_t)) { 291 error = EINVAL; 292 break; 293 } 294 xxxp->flags = *((u_int32_t *) msg->data); 295 break; 296 default: 297 error = EINVAL; /* unknown command */ 298 break; 299 } 300 break; 301 default: 302 error = EINVAL; /* unknown cookie type */ 303 break; 304 } 305 306 /* Take care of synchronous response, if any */ 307 NG_RESPOND_MSG(error, node, item, resp); 308 /* Free the message and return */ 309 NG_FREE_MSG(msg); 310 return(error); 311 } 312 313 /* 314 * Receive data, and do something with it. 315 * Actually we receive a queue item which holds the data. 316 * If we free the item it will also free the data unless we have 317 * previously disassociated it using the NGI_GET_M() macro. 318 * Possibly send it out on another link after processing. 319 * Possibly do something different if it comes from different 320 * hooks. The caller will never free m, so if we use up this data or 321 * abort we must free it. 322 * 323 * If we want, we may decide to force this data to be queued and reprocessed 324 * at the netgraph NETISR time. 325 * We would do that by setting the HK_QUEUE flag on our hook. We would do that 326 * in the connect() method. 327 */ 328 static int 329 ng_xxx_rcvdata(hook_p hook, item_p item ) 330 { 331 const xxx_p xxxp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 332 int chan = -2; 333 int dlci = -2; 334 int error; 335 struct mbuf *m; 336 337 NGI_GET_M(item, m); 338 if (NG_HOOK_PRIVATE(hook)) { 339 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 340 chan = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->channel; 341 if (dlci != -1) { 342 /* If received on a DLCI hook process for this 343 * channel and pass it to the downstream module. 344 * Normally one would add a multiplexing header at 345 * the front here */ 346 /* M_PREPEND(....) ; */ 347 /* mtod(m, xxxxxx)->dlci = dlci; */ 348 NG_FWD_NEW_DATA(error, item, 349 xxxp->downstream_hook.hook, m); 350 xxxp->packets_out++; 351 } else { 352 /* data came from the multiplexed link */ 353 dlci = 1; /* get dlci from header */ 354 /* madjust(....) *//* chop off header */ 355 for (chan = 0; chan < XXX_NUM_DLCIS; chan++) 356 if (xxxp->channel[chan].dlci == dlci) 357 break; 358 if (chan == XXX_NUM_DLCIS) { 359 NG_FREE_ITEM(item); 360 NG_FREE_M(m); 361 return (ENETUNREACH); 362 } 363 /* If we were called at splnet, use the following: 364 * NG_SEND_DATA_ONLY(error, otherhook, m); if this 365 * node is running at some SPL other than SPLNET 366 * then you should use instead: error = 367 * ng_queueit(otherhook, m, NULL); m = NULL; 368 * This queues the data using the standard NETISR 369 * system and schedules the data to be picked 370 * up again once the system has moved to SPLNET and 371 * the processing of the data can continue. After 372 * these are run 'm' should be considered 373 * as invalid and NG_SEND_DATA actually zaps them. */ 374 NG_FWD_NEW_DATA(error, item, 375 xxxp->channel[chan].hook, m); 376 xxxp->packets_in++; 377 } 378 } else { 379 /* It's the debug hook, throw it away.. */ 380 if (hook == xxxp->downstream_hook.hook) { 381 NG_FREE_ITEM(item); 382 NG_FREE_M(m); 383 } 384 } 385 return 0; 386 } 387 388 #if 0 389 /* 390 * If this were a device node, the data may have been received in response 391 * to some interrupt. 392 * in which case it would probably look as follows: 393 */ 394 devintr() 395 { 396 int error; 397 398 /* get packet from device and send on */ 399 m = MGET(blah blah) 400 401 NG_SEND_DATA_ONLY(error, xxxp->upstream_hook.hook, m); 402 /* see note above in xxx_rcvdata() */ 403 /* and ng_xxx_connect() */ 404 } 405 406 #endif /* 0 */ 407 408 /* 409 * Do local shutdown processing.. 410 * All our links and the name have already been removed. 411 * If we are a persistant device, we might refuse to go away. 412 * In the case of a persistant node we signal the framework that we 413 * are still in business by clearing the NGF_INVALID bit. However 414 * If we find the NGF_REALLY_DIE bit set, this means that 415 * we REALLY need to die (e.g. hardware removed). 416 * This would have been set using the NG_NODE_REALLY_DIE(node) 417 * macro in some device dependent function (not shown here) before 418 * calling ng_rmnode_self(). 419 */ 420 static int 421 ng_xxx_shutdown(node_p node) 422 { 423 const xxx_p privdata = NG_NODE_PRIVATE(node); 424 425 #ifndef PERSISTANT_NODE 426 NG_NODE_SET_PRIVATE(node, NULL); 427 NG_NODE_UNREF(node); 428 kfree(privdata, M_NETGRAPH); 429 #else 430 if (node->nd_flags & NGF_REALLY_DIE) { 431 /* 432 * WE came here because the widget card is being unloaded, 433 * so stop being persistant. 434 * Actually undo all the things we did on creation. 435 */ 436 NG_NODE_SET_PRIVATE(node, NULL); 437 NG_NODE_UNREF(privdata->node); 438 kfree(privdata, M_NETGRAPH); 439 return (0); 440 } 441 NG_NODE_REVIVE(node); /* tell ng_rmnode() we will persist */ 442 #endif /* PERSISTANT_NODE */ 443 return (0); 444 } 445 446 /* 447 * This is called once we've already connected a new hook to the other node. 448 * It gives us a chance to balk at the last minute. 449 */ 450 static int 451 ng_xxx_connect(hook_p hook) 452 { 453 #if 0 454 /* 455 * If we were a driver running at other than splnet then 456 * we should set the QUEUE bit on the edge so that we 457 * will deliver by queing. 458 */ 459 if /*it is the upstream hook */ 460 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 461 #endif 462 #if 0 463 /* 464 * If for some reason we want incoming date to be queued 465 * by the NETISR system and delivered later we can set the same bit on 466 * OUR hook. (maybe to allow unwinding of the stack) 467 */ 468 469 if (NG_HOOK_PRIVATE(hook)) { 470 int dlci; 471 /* 472 * If it's dlci 1023, requeue it so that it's handled 473 * at a lower priority. This is how a node decides to 474 * defer a data message. 475 */ 476 dlci = ((struct XXX_hookinfo *) NG_HOOK_PRIVATE(hook))->dlci; 477 if (dlci == 1023) { 478 NG_HOOK_FORCE_QUEUE(hook); 479 } 480 #endif 481 /* otherwise be really amiable and just say "YUP that's OK by me! " */ 482 return (0); 483 } 484 485 /* 486 * Hook disconnection 487 * 488 * For this type, removal of the last link destroys the node 489 */ 490 static int 491 ng_xxx_disconnect(hook_p hook) 492 { 493 if (NG_HOOK_PRIVATE(hook)) 494 ((struct XXX_hookinfo *) (NG_HOOK_PRIVATE(hook)))->hook = NULL; 495 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 496 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */ 497 ng_rmnode_self(NG_HOOK_NODE(hook)); 498 return (0); 499 } 500 501