ng_device.c revision 183381
1/*- 2 * Copyright (c) 2002 Mark Santcroos <marks@ripe.net> 3 * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org> 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 * 25 * Netgraph "device" node 26 * 27 * This node presents a /dev/ngd%d device that interfaces to an other 28 * netgraph node. 29 * 30 * $FreeBSD: head/sys/netgraph/ng_device.c 183381 2008-09-26 14:19:52Z ed $ 31 * 32 */ 33 34#if 0 35#define DBG do { printf("ng_device: %s\n", __func__ ); } while (0) 36#else 37#define DBG do {} while (0) 38#endif 39 40#include <sys/param.h> 41#include <sys/conf.h> 42#include <sys/ioccom.h> 43#include <sys/kernel.h> 44#include <sys/malloc.h> 45#include <sys/mbuf.h> 46#include <sys/poll.h> 47#include <sys/queue.h> 48#include <sys/socket.h> 49#include <sys/systm.h> 50#include <sys/uio.h> 51#include <sys/vnode.h> 52 53#include <net/if.h> 54#include <net/if_var.h> 55#include <netinet/in.h> 56#include <netinet/in_systm.h> 57#include <netinet/ip.h> 58 59#include <netgraph/ng_message.h> 60#include <netgraph/netgraph.h> 61#include <netgraph/ng_device.h> 62 63#define ERROUT(x) do { error = (x); goto done; } while (0) 64 65/* Netgraph methods */ 66static int ng_device_mod_event(module_t, int, void *); 67static ng_constructor_t ng_device_constructor; 68static ng_rcvmsg_t ng_device_rcvmsg; 69static ng_shutdown_t ng_device_shutdown; 70static ng_newhook_t ng_device_newhook; 71static ng_rcvdata_t ng_device_rcvdata; 72static ng_disconnect_t ng_device_disconnect; 73 74/* Netgraph type */ 75static struct ng_type ngd_typestruct = { 76 .version = NG_ABI_VERSION, 77 .name = NG_DEVICE_NODE_TYPE, 78 .mod_event = ng_device_mod_event, 79 .constructor = ng_device_constructor, 80 .rcvmsg = ng_device_rcvmsg, 81 .shutdown = ng_device_shutdown, 82 .newhook = ng_device_newhook, 83 .rcvdata = ng_device_rcvdata, 84 .disconnect = ng_device_disconnect, 85}; 86NETGRAPH_INIT(device, &ngd_typestruct); 87 88/* per node data */ 89struct ngd_private { 90 struct ifqueue readq; 91 struct ng_node *node; 92 struct ng_hook *hook; 93 struct cdev *ngddev; 94 struct mtx ngd_mtx; 95 int unit; 96 uint16_t flags; 97#define NGDF_OPEN 0x0001 98#define NGDF_RWAIT 0x0002 99}; 100typedef struct ngd_private *priv_p; 101 102/* unit number allocator entity */ 103static struct unrhdr *ngd_unit; 104 105/* Maximum number of NGD devices */ 106#define MAX_NGD 999 107 108static d_close_t ngdclose; 109static d_open_t ngdopen; 110static d_read_t ngdread; 111static d_write_t ngdwrite; 112#if 0 113static d_ioctl_t ngdioctl; 114#endif 115static d_poll_t ngdpoll; 116 117static struct cdevsw ngd_cdevsw = { 118 .d_version = D_VERSION, 119 .d_open = ngdopen, 120 .d_close = ngdclose, 121 .d_read = ngdread, 122 .d_write = ngdwrite, 123#if 0 124 .d_ioctl = ngdioctl, 125#endif 126 .d_poll = ngdpoll, 127 .d_name = NG_DEVICE_DEVNAME, 128}; 129 130/****************************************************************************** 131 * Netgraph methods 132 ******************************************************************************/ 133 134/* 135 * Handle loading and unloading for this node type. 136 */ 137static int 138ng_device_mod_event(module_t mod, int event, void *data) 139{ 140 int error = 0; 141 142 switch (event) { 143 case MOD_LOAD: 144 ngd_unit = new_unrhdr(0, MAX_NGD, NULL); 145 break; 146 case MOD_UNLOAD: 147 delete_unrhdr(ngd_unit); 148 break; 149 default: 150 error = EOPNOTSUPP; 151 break; 152 } 153 return (error); 154} 155 156/* 157 * create new node 158 */ 159static int 160ng_device_constructor(node_p node) 161{ 162 priv_p priv; 163 164 DBG; 165 166 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 167 if (priv == NULL) 168 return (ENOMEM); 169 170 /* Allocate unit number */ 171 priv->unit = alloc_unr(ngd_unit); 172 173 /* Initialize mutexes and queue */ 174 mtx_init(&priv->ngd_mtx, "ng_device", NULL, MTX_DEF); 175 mtx_init(&priv->readq.ifq_mtx, "ng_device queue", NULL, MTX_DEF); 176 IFQ_SET_MAXLEN(&priv->readq, ifqmaxlen); 177 178 /* Link everything together */ 179 NG_NODE_SET_PRIVATE(node, priv); 180 priv->node = node; 181 182 priv->ngddev = make_dev(&ngd_cdevsw, priv->unit, UID_ROOT, 183 GID_WHEEL, 0600, NG_DEVICE_DEVNAME "%d", priv->unit); 184 if(priv->ngddev == NULL) { 185 printf("%s(): make_dev() failed\n",__func__); 186 mtx_destroy(&priv->ngd_mtx); 187 mtx_destroy(&priv->readq.ifq_mtx); 188 free_unr(ngd_unit, priv->unit); 189 FREE(priv, M_NETGRAPH); 190 return(EINVAL); 191 } 192 /* XXX: race here? */ 193 priv->ngddev->si_drv1 = priv; 194 195 return(0); 196} 197 198/* 199 * Process control message. 200 */ 201 202static int 203ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook) 204{ 205 const priv_p priv = NG_NODE_PRIVATE(node); 206 struct ng_mesg *msg; 207 struct ng_mesg *resp = NULL; 208 int error = 0; 209 210 NGI_GET_MSG(item, msg); 211 212 if (msg->header.typecookie == NGM_DEVICE_COOKIE) { 213 switch (msg->header.cmd) { 214 case NGM_DEVICE_GET_DEVNAME: 215 /* XXX: Fix when MAX_NGD us bigger */ 216 NG_MKRESPONSE(resp, msg, 217 strlen(NG_DEVICE_DEVNAME) + 4, M_NOWAIT); 218 219 if (resp == NULL) 220 ERROUT(ENOMEM); 221 222 strlcpy((char *)resp->data, priv->ngddev->si_name, 223 strlen(priv->ngddev->si_name) + 1); 224 break; 225 226 default: 227 error = EINVAL; 228 break; 229 } 230 } else 231 error = EINVAL; 232 233done: 234 NG_RESPOND_MSG(error, node, item, resp); 235 NG_FREE_MSG(msg); 236 return (error); 237} 238 239/* 240 * Accept incoming hook. We support only one hook per node. 241 */ 242static int 243ng_device_newhook(node_p node, hook_p hook, const char *name) 244{ 245 priv_p priv = NG_NODE_PRIVATE(node); 246 247 DBG; 248 249 /* We have only one hook per node */ 250 if (priv->hook != NULL) 251 return (EISCONN); 252 253 priv->hook = hook; 254 255 return(0); 256} 257 258/* 259 * Receive data from hook, write it to device. 260 */ 261static int 262ng_device_rcvdata(hook_p hook, item_p item) 263{ 264 priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 265 struct mbuf *m; 266 267 DBG; 268 269 NGI_GET_M(item, m); 270 NG_FREE_ITEM(item); 271 272 IF_LOCK(&priv->readq); 273 if (_IF_QFULL(&priv->readq)) { 274 _IF_DROP(&priv->readq); 275 IF_UNLOCK(&priv->readq); 276 NG_FREE_M(m); 277 return (ENOBUFS); 278 } 279 280 _IF_ENQUEUE(&priv->readq, m); 281 IF_UNLOCK(&priv->readq); 282 mtx_lock(&priv->ngd_mtx); 283 if (priv->flags & NGDF_RWAIT) { 284 priv->flags &= ~NGDF_RWAIT; 285 wakeup(priv); 286 } 287 mtx_unlock(&priv->ngd_mtx); 288 289 return(0); 290} 291 292/* 293 * Removal of the hook destroys the node. 294 */ 295static int 296ng_device_disconnect(hook_p hook) 297{ 298 priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 299 300 DBG; 301 302 destroy_dev(priv->ngddev); 303 mtx_destroy(&priv->ngd_mtx); 304 305 IF_DRAIN(&priv->readq); 306 mtx_destroy(&(priv)->readq.ifq_mtx); 307 308 free_unr(ngd_unit, priv->unit); 309 310 FREE(priv, M_NETGRAPH); 311 312 ng_rmnode_self(NG_HOOK_NODE(hook)); 313 314 return(0); 315} 316 317/* 318 * Node shutdown. Everything is already done in disconnect method. 319 */ 320static int 321ng_device_shutdown(node_p node) 322{ 323 NG_NODE_UNREF(node); 324 return (0); 325} 326 327/****************************************************************************** 328 * Device methods 329 ******************************************************************************/ 330 331/* 332 * the device is opened 333 */ 334static int 335ngdopen(struct cdev *dev, int flag, int mode, struct thread *td) 336{ 337 priv_p priv = (priv_p )dev->si_drv1; 338 339 DBG; 340 341 mtx_lock(&priv->ngd_mtx); 342 priv->flags |= NGDF_OPEN; 343 mtx_unlock(&priv->ngd_mtx); 344 345 return(0); 346} 347 348/* 349 * the device is closed 350 */ 351static int 352ngdclose(struct cdev *dev, int flag, int mode, struct thread *td) 353{ 354 priv_p priv = (priv_p )dev->si_drv1; 355 356 DBG; 357 mtx_lock(&priv->ngd_mtx); 358 priv->flags &= ~NGDF_OPEN; 359 mtx_unlock(&priv->ngd_mtx); 360 361 return(0); 362} 363 364#if 0 /* 365 * The ioctl is transformed into netgraph control message. 366 * We do not process them, yet. 367 */ 368/* 369 * process ioctl 370 * 371 * they are translated into netgraph messages and passed on 372 * 373 */ 374static int 375ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td) 376{ 377 struct ngd_softc *sc = &ngd_softc; 378 struct ngd_connection * connection = NULL; 379 struct ngd_connection * tmp; 380 int error = 0; 381 struct ng_mesg *msg; 382 struct ngd_param_s * datap; 383 384 DBG; 385 386 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s), 387 M_NOWAIT); 388 if (msg == NULL) { 389 printf("%s(): msg == NULL\n",__func__); 390 goto nomsg; 391 } 392 393 /* pass the ioctl data into the ->data area */ 394 datap = (struct ngd_param_s *)msg->data; 395 datap->p = addr; 396 397 NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, 0); 398 if(error) 399 printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error); 400 401nomsg: 402 403 return(0); 404} 405#endif /* if 0 */ 406 407/* 408 * This function is called when a read(2) is done to our device. 409 * We process one mbuf from queue. 410 */ 411static int 412ngdread(struct cdev *dev, struct uio *uio, int flag) 413{ 414 priv_p priv = (priv_p )dev->si_drv1; 415 struct mbuf *m; 416 int len, error = 0; 417 418 DBG; 419 420 /* get an mbuf */ 421 do { 422 IF_DEQUEUE(&priv->readq, m); 423 if (m == NULL) { 424 if (flag & IO_NDELAY) 425 return (EWOULDBLOCK); 426 mtx_lock(&priv->ngd_mtx); 427 priv->flags |= NGDF_RWAIT; 428 if ((error = msleep(priv, &priv->ngd_mtx, 429 PDROP | PCATCH | (PZERO + 1), 430 "ngdread", 0)) != 0) 431 return (error); 432 } 433 } while (m == NULL); 434 435 while (m && uio->uio_resid > 0 && error == 0) { 436 len = MIN(uio->uio_resid, m->m_len); 437 if (len != 0) 438 error = uiomove(mtod(m, void *), len, uio); 439 m = m_free(m); 440 } 441 442 if (m) 443 m_freem(m); 444 445 return (error); 446} 447 448 449/* 450 * This function is called when our device is written to. 451 * We read the data from userland into mbuf chain and pass it to the remote hook. 452 * 453 */ 454static int 455ngdwrite(struct cdev *dev, struct uio *uio, int flag) 456{ 457 priv_p priv = (priv_p )dev->si_drv1; 458 struct mbuf *m; 459 int error = 0; 460 461 DBG; 462 463 if (uio->uio_resid == 0) 464 return (0); 465 466 if (uio->uio_resid < 0 || uio->uio_resid > IP_MAXPACKET) 467 return (EIO); 468 469 if ((m = m_uiotombuf(uio, M_DONTWAIT, 0, 0, M_PKTHDR)) == NULL) 470 return (ENOBUFS); 471 472 NG_SEND_DATA_ONLY(error, priv->hook, m); 473 474 return (error); 475} 476 477/* 478 * we are being polled/selected 479 * check if there is data available for read 480 */ 481static int 482ngdpoll(struct cdev *dev, int events, struct thread *td) 483{ 484 priv_p priv = (priv_p )dev->si_drv1; 485 int revents = 0; 486 487 if (events & (POLLIN | POLLRDNORM) && 488 !IFQ_IS_EMPTY(&priv->readq)) 489 revents |= events & (POLLIN | POLLRDNORM); 490 491 return (revents); 492} 493