ng_device.c revision 285830
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: releng/10.2/sys/netgraph/ng_device.c 243882 2012-12-05 08:04:20Z glebius $ 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 priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO); 167 168 /* Allocate unit number */ 169 priv->unit = alloc_unr(ngd_unit); 170 171 /* Initialize mutexes and queue */ 172 mtx_init(&priv->ngd_mtx, "ng_device", NULL, MTX_DEF); 173 mtx_init(&priv->readq.ifq_mtx, "ng_device queue", NULL, MTX_DEF); 174 IFQ_SET_MAXLEN(&priv->readq, ifqmaxlen); 175 176 /* Link everything together */ 177 NG_NODE_SET_PRIVATE(node, priv); 178 priv->node = node; 179 180 priv->ngddev = make_dev(&ngd_cdevsw, priv->unit, UID_ROOT, 181 GID_WHEEL, 0600, NG_DEVICE_DEVNAME "%d", priv->unit); 182 if(priv->ngddev == NULL) { 183 printf("%s(): make_dev() failed\n",__func__); 184 mtx_destroy(&priv->ngd_mtx); 185 mtx_destroy(&priv->readq.ifq_mtx); 186 free_unr(ngd_unit, priv->unit); 187 free(priv, M_NETGRAPH); 188 return(EINVAL); 189 } 190 /* XXX: race here? */ 191 priv->ngddev->si_drv1 = priv; 192 193 return(0); 194} 195 196/* 197 * Process control message. 198 */ 199 200static int 201ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook) 202{ 203 const priv_p priv = NG_NODE_PRIVATE(node); 204 struct ng_mesg *msg; 205 struct ng_mesg *resp = NULL; 206 const char *dn; 207 int error = 0; 208 209 NGI_GET_MSG(item, msg); 210 211 if (msg->header.typecookie == NGM_DEVICE_COOKIE) { 212 switch (msg->header.cmd) { 213 case NGM_DEVICE_GET_DEVNAME: 214 /* XXX: Fix when MAX_NGD us bigger */ 215 NG_MKRESPONSE(resp, msg, 216 strlen(NG_DEVICE_DEVNAME) + 4, M_NOWAIT); 217 218 if (resp == NULL) 219 ERROUT(ENOMEM); 220 221 dn = devtoname(priv->ngddev); 222 strlcpy((char *)resp->data, dn, strlen(dn) + 1); 223 break; 224 225 default: 226 error = EINVAL; 227 break; 228 } 229 } else 230 error = EINVAL; 231 232done: 233 NG_RESPOND_MSG(error, node, item, resp); 234 NG_FREE_MSG(msg); 235 return (error); 236} 237 238/* 239 * Accept incoming hook. We support only one hook per node. 240 */ 241static int 242ng_device_newhook(node_p node, hook_p hook, const char *name) 243{ 244 priv_p priv = NG_NODE_PRIVATE(node); 245 246 DBG; 247 248 /* We have only one hook per node */ 249 if (priv->hook != NULL) 250 return (EISCONN); 251 252 priv->hook = hook; 253 254 return(0); 255} 256 257/* 258 * Receive data from hook, write it to device. 259 */ 260static int 261ng_device_rcvdata(hook_p hook, item_p item) 262{ 263 priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 264 struct mbuf *m; 265 266 DBG; 267 268 NGI_GET_M(item, m); 269 NG_FREE_ITEM(item); 270 271 IF_LOCK(&priv->readq); 272 if (_IF_QFULL(&priv->readq)) { 273 _IF_DROP(&priv->readq); 274 IF_UNLOCK(&priv->readq); 275 NG_FREE_M(m); 276 return (ENOBUFS); 277 } 278 279 _IF_ENQUEUE(&priv->readq, m); 280 IF_UNLOCK(&priv->readq); 281 mtx_lock(&priv->ngd_mtx); 282 if (priv->flags & NGDF_RWAIT) { 283 priv->flags &= ~NGDF_RWAIT; 284 wakeup(priv); 285 } 286 mtx_unlock(&priv->ngd_mtx); 287 288 return(0); 289} 290 291/* 292 * Removal of the hook destroys the node. 293 */ 294static int 295ng_device_disconnect(hook_p hook) 296{ 297 priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 298 299 DBG; 300 301 destroy_dev(priv->ngddev); 302 mtx_destroy(&priv->ngd_mtx); 303 304 IF_DRAIN(&priv->readq); 305 mtx_destroy(&(priv)->readq.ifq_mtx); 306 307 free_unr(ngd_unit, priv->unit); 308 309 free(priv, M_NETGRAPH); 310 311 ng_rmnode_self(NG_HOOK_NODE(hook)); 312 313 return(0); 314} 315 316/* 317 * Node shutdown. Everything is already done in disconnect method. 318 */ 319static int 320ng_device_shutdown(node_p node) 321{ 322 NG_NODE_UNREF(node); 323 return (0); 324} 325 326/****************************************************************************** 327 * Device methods 328 ******************************************************************************/ 329 330/* 331 * the device is opened 332 */ 333static int 334ngdopen(struct cdev *dev, int flag, int mode, struct thread *td) 335{ 336 priv_p priv = (priv_p )dev->si_drv1; 337 338 DBG; 339 340 mtx_lock(&priv->ngd_mtx); 341 priv->flags |= NGDF_OPEN; 342 mtx_unlock(&priv->ngd_mtx); 343 344 return(0); 345} 346 347/* 348 * the device is closed 349 */ 350static int 351ngdclose(struct cdev *dev, int flag, int mode, struct thread *td) 352{ 353 priv_p priv = (priv_p )dev->si_drv1; 354 355 DBG; 356 mtx_lock(&priv->ngd_mtx); 357 priv->flags &= ~NGDF_OPEN; 358 mtx_unlock(&priv->ngd_mtx); 359 360 return(0); 361} 362 363#if 0 /* 364 * The ioctl is transformed into netgraph control message. 365 * We do not process them, yet. 366 */ 367/* 368 * process ioctl 369 * 370 * they are translated into netgraph messages and passed on 371 * 372 */ 373static int 374ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td) 375{ 376 struct ngd_softc *sc = &ngd_softc; 377 struct ngd_connection * connection = NULL; 378 struct ngd_connection * tmp; 379 int error = 0; 380 struct ng_mesg *msg; 381 struct ngd_param_s * datap; 382 383 DBG; 384 385 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s), 386 M_NOWAIT); 387 if (msg == NULL) { 388 printf("%s(): msg == NULL\n",__func__); 389 goto nomsg; 390 } 391 392 /* pass the ioctl data into the ->data area */ 393 datap = (struct ngd_param_s *)msg->data; 394 datap->p = addr; 395 396 NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, 0); 397 if(error) 398 printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error); 399 400nomsg: 401 402 return(0); 403} 404#endif /* if 0 */ 405 406/* 407 * This function is called when a read(2) is done to our device. 408 * We process one mbuf from queue. 409 */ 410static int 411ngdread(struct cdev *dev, struct uio *uio, int flag) 412{ 413 priv_p priv = (priv_p )dev->si_drv1; 414 struct mbuf *m; 415 int len, error = 0; 416 417 DBG; 418 419 /* get an mbuf */ 420 do { 421 IF_DEQUEUE(&priv->readq, m); 422 if (m == NULL) { 423 if (flag & IO_NDELAY) 424 return (EWOULDBLOCK); 425 mtx_lock(&priv->ngd_mtx); 426 priv->flags |= NGDF_RWAIT; 427 if ((error = msleep(priv, &priv->ngd_mtx, 428 PDROP | PCATCH | (PZERO + 1), 429 "ngdread", 0)) != 0) 430 return (error); 431 } 432 } while (m == NULL); 433 434 while (m && uio->uio_resid > 0 && error == 0) { 435 len = MIN(uio->uio_resid, m->m_len); 436 if (len != 0) 437 error = uiomove(mtod(m, void *), len, uio); 438 m = m_free(m); 439 } 440 441 if (m) 442 m_freem(m); 443 444 return (error); 445} 446 447 448/* 449 * This function is called when our device is written to. 450 * We read the data from userland into mbuf chain and pass it to the remote hook. 451 * 452 */ 453static int 454ngdwrite(struct cdev *dev, struct uio *uio, int flag) 455{ 456 priv_p priv = (priv_p )dev->si_drv1; 457 struct mbuf *m; 458 int error = 0; 459 460 DBG; 461 462 if (uio->uio_resid == 0) 463 return (0); 464 465 if (uio->uio_resid < 0 || uio->uio_resid > IP_MAXPACKET) 466 return (EIO); 467 468 if ((m = m_uiotombuf(uio, M_NOWAIT, 0, 0, M_PKTHDR)) == NULL) 469 return (ENOBUFS); 470 471 NG_SEND_DATA_ONLY(error, priv->hook, m); 472 473 return (error); 474} 475 476/* 477 * we are being polled/selected 478 * check if there is data available for read 479 */ 480static int 481ngdpoll(struct cdev *dev, int events, struct thread *td) 482{ 483 priv_p priv = (priv_p )dev->si_drv1; 484 int revents = 0; 485 486 if (events & (POLLIN | POLLRDNORM) && 487 !IFQ_IS_EMPTY(&priv->readq)) 488 revents |= events & (POLLIN | POLLRDNORM); 489 490 return (revents); 491} 492