1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002 Mark Santcroos <marks@ripe.net> 5 * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * 27 * Netgraph "device" node 28 * 29 * This node presents a /dev/ngd%d device that interfaces to an other 30 * netgraph node. 31 * 32 * $FreeBSD$ 33 * 34 */ 35 36 #if 0 37 #define DBG do { printf("ng_device: %s\n", __func__ ); } while (0) 38 #else 39 #define DBG do {} while (0) 40 #endif 41 42 #include <sys/param.h> 43 #include <sys/conf.h> 44 #include <sys/ioccom.h> 45 #include <sys/kernel.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/poll.h> 49 #include <sys/queue.h> 50 #include <sys/socket.h> 51 #include <sys/systm.h> 52 #include <sys/uio.h> 53 #include <sys/vnode.h> 54 55 #include <net/if.h> 56 #include <net/if_var.h> 57 #include <netinet/in.h> 58 #include <netinet/in_systm.h> 59 #include <netinet/ip.h> 60 61 #include <netgraph/ng_message.h> 62 #include <netgraph/netgraph.h> 63 #include <netgraph/ng_device.h> 64 65 #define ERROUT(x) do { error = (x); goto done; } while (0) 66 67 /* Netgraph methods */ 68 static int ng_device_mod_event(module_t, int, void *); 69 static ng_constructor_t ng_device_constructor; 70 static ng_rcvmsg_t ng_device_rcvmsg; 71 static ng_shutdown_t ng_device_shutdown; 72 static ng_newhook_t ng_device_newhook; 73 static ng_rcvdata_t ng_device_rcvdata; 74 static ng_disconnect_t ng_device_disconnect; 75 76 /* Netgraph type */ 77 static struct ng_type ngd_typestruct = { 78 .version = NG_ABI_VERSION, 79 .name = NG_DEVICE_NODE_TYPE, 80 .mod_event = ng_device_mod_event, 81 .constructor = ng_device_constructor, 82 .rcvmsg = ng_device_rcvmsg, 83 .shutdown = ng_device_shutdown, 84 .newhook = ng_device_newhook, 85 .rcvdata = ng_device_rcvdata, 86 .disconnect = ng_device_disconnect, 87 }; 88 NETGRAPH_INIT(device, &ngd_typestruct); 89 90 /* per node data */ 91 struct ngd_private { 92 struct ifqueue readq; 93 struct ng_node *node; 94 struct ng_hook *hook; 95 struct cdev *ngddev; 96 struct mtx ngd_mtx; 97 int unit; 98 uint16_t flags; 99 #define NGDF_OPEN 0x0001 100 #define NGDF_RWAIT 0x0002 101 }; 102 typedef struct ngd_private *priv_p; 103 104 /* unit number allocator entity */ 105 static struct unrhdr *ngd_unit; 106 107 /* Maximum number of NGD devices */ 108 #define MAX_NGD 999 109 110 static d_close_t ngdclose; 111 static d_open_t ngdopen; 112 static d_read_t ngdread; 113 static d_write_t ngdwrite; 114 #if 0 115 static d_ioctl_t ngdioctl; 116 #endif 117 static d_poll_t ngdpoll; 118 119 static struct cdevsw ngd_cdevsw = { 120 .d_version = D_VERSION, 121 .d_open = ngdopen, 122 .d_close = ngdclose, 123 .d_read = ngdread, 124 .d_write = ngdwrite, 125 #if 0 126 .d_ioctl = ngdioctl, 127 #endif 128 .d_poll = ngdpoll, 129 .d_name = NG_DEVICE_DEVNAME, 130 }; 131 132 /****************************************************************************** 133 * Netgraph methods 134 ******************************************************************************/ 135 136 /* 137 * Handle loading and unloading for this node type. 138 */ 139 static int 140 ng_device_mod_event(module_t mod, int event, void *data) 141 { 142 int error = 0; 143 144 switch (event) { 145 case MOD_LOAD: 146 ngd_unit = new_unrhdr(0, MAX_NGD, NULL); 147 break; 148 case MOD_UNLOAD: 149 delete_unrhdr(ngd_unit); 150 break; 151 default: 152 error = EOPNOTSUPP; 153 break; 154 } 155 return (error); 156 } 157 158 /* 159 * create new node 160 */ 161 static int 162 ng_device_constructor(node_p node) 163 { 164 priv_p priv; 165 166 DBG; 167 168 priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO); 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 */ 201 202 static int 203 ng_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 const char *dn; 209 int error = 0; 210 211 NGI_GET_MSG(item, msg); 212 213 if (msg->header.typecookie == NGM_DEVICE_COOKIE) { 214 switch (msg->header.cmd) { 215 case NGM_DEVICE_GET_DEVNAME: 216 /* XXX: Fix when MAX_NGD us bigger */ 217 NG_MKRESPONSE(resp, msg, 218 strlen(NG_DEVICE_DEVNAME) + 4, M_NOWAIT); 219 220 if (resp == NULL) 221 ERROUT(ENOMEM); 222 223 dn = devtoname(priv->ngddev); 224 strlcpy((char *)resp->data, dn, strlen(dn) + 1); 225 break; 226 227 default: 228 error = EINVAL; 229 break; 230 } 231 } else 232 error = EINVAL; 233 234 done: 235 NG_RESPOND_MSG(error, node, item, resp); 236 NG_FREE_MSG(msg); 237 return (error); 238 } 239 240 /* 241 * Accept incoming hook. We support only one hook per node. 242 */ 243 static int 244 ng_device_newhook(node_p node, hook_p hook, const char *name) 245 { 246 priv_p priv = NG_NODE_PRIVATE(node); 247 248 DBG; 249 250 /* We have only one hook per node */ 251 if (priv->hook != NULL) 252 return (EISCONN); 253 254 priv->hook = hook; 255 256 return(0); 257 } 258 259 /* 260 * Receive data from hook, write it to device. 261 */ 262 static int 263 ng_device_rcvdata(hook_p hook, item_p item) 264 { 265 priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 266 struct mbuf *m; 267 268 DBG; 269 270 NGI_GET_M(item, m); 271 NG_FREE_ITEM(item); 272 273 IF_LOCK(&priv->readq); 274 if (_IF_QFULL(&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 */ 295 static int 296 ng_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 */ 320 static int 321 ng_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 */ 334 static int 335 ngdopen(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 */ 351 static int 352 ngdclose(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 */ 374 static int 375 ngdioctl(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); 400 401 nomsg: 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 */ 411 static int 412 ngdread(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 */ 454 static int 455 ngdwrite(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_NOWAIT, 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 */ 481 static int 482 ngdpoll(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