1 /* 2 * Copyright (c) 2002 Mark Santcroos <marks@ripe.net> 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * Netgraph "device" node 27 * 28 * This node presents a /dev/ngd%d device that interfaces to an other 29 * netgraph node. 30 * 31 * $FreeBSD: src/sys/netgraph/ng_device.c,v 1.1.2.1 2002/08/23 07:15:44 julian Exp $ 32 * $DragonFly: src/sys/netgraph/ng_device.c,v 1.6 2006/01/14 11:10:47 swildner Exp $ 33 * 34 */ 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/mbuf.h> 40 #include <sys/uio.h> 41 #include <sys/queue.h> 42 #include <sys/malloc.h> 43 #include <sys/conf.h> 44 #include <sys/poll.h> 45 #include <sys/ioccom.h> 46 47 #include <netgraph/ng_message.h> 48 #include <netgraph/netgraph.h> 49 50 #include "ng_device.h" 51 52 /* turn this on for verbose messages */ 53 #define NGD_DEBUG 54 55 /* Netgraph methods */ 56 static ng_constructor_t ng_device_cons; 57 static ng_rcvmsg_t ng_device_rcvmsg; 58 static ng_newhook_t ng_device_newhook; 59 static ng_connect_t ng_device_connect; 60 static ng_rcvdata_t ng_device_rcvdata; 61 static ng_disconnect_t ng_device_disconnect; 62 static int ng_device_mod_event(module_t mod, int event, void *data); 63 64 static int ng_device_init(void); 65 static int get_free_unit(void); 66 67 /* Netgraph type */ 68 static struct ng_type typestruct = { 69 NG_VERSION, /* version */ 70 NG_DEVICE_NODE_TYPE, /* name */ 71 ng_device_mod_event, /* modevent */ 72 ng_device_cons, /* constructor */ 73 ng_device_rcvmsg, /* receive msg */ 74 NULL, /* shutdown */ 75 ng_device_newhook, /* newhook */ 76 NULL, /* findhook */ 77 ng_device_connect, /* connect */ 78 ng_device_rcvdata, /* receive data */ 79 ng_device_rcvdata, /* receive queued data */ 80 ng_device_disconnect, /* disconnect */ 81 NULL 82 }; 83 NETGRAPH_INIT(device, &typestruct); 84 85 /* per hook data */ 86 struct ngd_connection { 87 SLIST_ENTRY(ngd_connection) links; 88 89 dev_t ngddev; 90 struct ng_hook *active_hook; 91 char *readq; 92 int loc; 93 int unit; 94 }; 95 96 /* global data */ 97 struct ngd_softc { 98 SLIST_HEAD(, ngd_connection) head; 99 100 node_p node; 101 char nodename[NG_NODELEN + 1]; 102 } ngd_softc; 103 104 /* helper definition */ 105 #define MIN(a, b) ((a) < (b) ? (a) : (b)) 106 107 /* the per connection receiving queue maximum */ 108 #define NGD_QUEUE_SIZE (1024*10) 109 110 /* Maximum number of NGD devices */ 111 #define MAX_NGD 25 /* should be more than enough for now */ 112 113 static d_close_t ngdclose; 114 static d_open_t ngdopen; 115 static d_read_t ngdread; 116 static d_write_t ngdwrite; 117 static d_ioctl_t ngdioctl; 118 static d_poll_t ngdpoll; 119 120 #define NGD_CDEV_MAJOR 20 121 static struct cdevsw ngd_cdevsw = { 122 /* name */ "ngd", 123 /* maj */ NGD_CDEV_MAJOR, 124 /* flags */ 0, 125 /* port */ NULL, 126 /* clone */ NULL, 127 128 /* open */ ngdopen, 129 /* close */ ngdclose, 130 /* read */ ngdread, 131 /* write */ ngdwrite, 132 /* ioctl */ ngdioctl, 133 /* poll */ ngdpoll, 134 /* mmap */ nommap, 135 /* strategy */ nostrategy, 136 /* dump */ nodump, 137 /* psize */ nopsize 138 }; 139 140 /* 141 * this holds all the stuff that should be done at load time 142 */ 143 static int 144 ng_device_mod_event(module_t mod, int event, void *data) 145 { 146 int error = 0; 147 148 #ifdef NGD_DEBUG 149 printf("%s()\n", __func__); 150 #endif /* NGD_DEBUG */ 151 152 switch (event) { 153 case MOD_LOAD: 154 cdevsw_add(&ngd_cdevsw, 0, 0); 155 ng_device_init(); 156 break; 157 158 case MOD_UNLOAD: 159 /* XXX do we need to do something specific ? */ 160 /* ng_device_breakdown */ 161 cdevsw_remove(&ngd_cdevsw, 0, 0); 162 error = EBUSY; /* no unload! */ 163 break; 164 165 166 default: 167 error = EOPNOTSUPP; 168 break; 169 } 170 171 return(error); 172 } 173 174 175 static int 176 ng_device_init(void) 177 { 178 struct ngd_softc *sc = &ngd_softc; 179 180 #ifdef NGD_DEBUG 181 printf("%s()\n", __func__); 182 #endif /* NGD_DEBUG */ 183 184 SLIST_INIT(&sc->head); 185 186 if (ng_make_node_common(&typestruct, &sc->node) != 0) { 187 printf("%s(): ng_make_node_common failed\n", __func__); 188 return(ENXIO); 189 } 190 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE); 191 if (ng_name_node(sc->node, sc->nodename)) { 192 NG_NODE_UNREF(sc->node); /* make it go away again */ 193 printf("%s(): ng_name_node failed\n", __func__); 194 return(ENXIO); 195 } 196 NG_NODE_SET_PRIVATE(sc->node, sc); 197 198 return(0); 199 } 200 201 /* 202 * don't allow to be created, only the device can do that 203 */ 204 static int 205 ng_device_cons(node_p node) 206 { 207 208 #ifdef NGD_DEBUG 209 printf("%s()\n", __func__); 210 #endif /* NGD_DEBUG */ 211 212 return(EINVAL); 213 } 214 215 /* 216 * Receive control message. We just free it. 217 */ 218 static int 219 ng_device_rcvmsg(node_p node, 220 struct ng_mesg *msg, const char *retaddr, struct ng_mesg **rptr) 221 { 222 FREE(msg, M_NETGRAPH); 223 return(ENOTTY); 224 } 225 226 static int 227 get_free_unit(void) 228 { 229 struct ngd_connection *tmp = NULL; 230 struct ngd_softc *sc = &ngd_softc; 231 int n = 0; 232 int unit = -1; 233 234 #ifdef NGD_DEBUG 235 printf("%s()\n", __func__); 236 #endif /* NGD_DEBUG */ 237 238 /* When there is no list yet, the first device unit is always 0. */ 239 if SLIST_EMPTY(&sc->head) { 240 unit = 0; 241 return(unit); 242 } 243 244 /* Just do a brute force loop to find the first free unit that is 245 * smaller than MAX_NGD. 246 * Set MAX_NGD to a large value, doesn't impact performance. 247 */ 248 for(n = 0;n<MAX_NGD && unit == -1;n++) { 249 SLIST_FOREACH(tmp, &sc->head, links) { 250 251 if(tmp->unit == n) { 252 unit = -1; 253 break; 254 } 255 unit = n; 256 } 257 } 258 259 return(unit); 260 } 261 262 /* 263 * incoming hook 264 */ 265 static int 266 ng_device_newhook(node_p node, hook_p hook, const char *name) 267 { 268 struct ngd_softc *sc = &ngd_softc; 269 struct ngd_connection * new_connection = NULL; 270 271 #ifdef NGD_DEBUG 272 printf("%s()\n", __func__); 273 #endif /* NGD_DEBUG */ 274 275 new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT); 276 if(new_connection == NULL) { 277 printf("%s(): ERROR: new_connection == NULL\n", __func__); 278 return(-1); 279 } 280 281 new_connection->unit = get_free_unit(); 282 if(new_connection->unit<0) { 283 printf("%s: No free unit found by get_free_unit(), " 284 "increas MAX_NGD\n", __func__); 285 free(new_connection, M_DEVBUF); 286 return(-1); 287 } 288 new_connection->ngddev = make_dev(&ngd_cdevsw, 289 new_connection->unit, 0, 0, 0600, "ngd%d", new_connection->unit); 290 if(new_connection->ngddev == NULL) { 291 printf("%s(): make_dev failed\n", __func__); 292 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links); 293 free(new_connection, M_DEVBUF); 294 return(-1); 295 } 296 297 new_connection->readq = 298 malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO); 299 if(new_connection->readq == NULL) { 300 printf("%s(): readq malloc failed\n", __func__); 301 destroy_dev(new_connection->ngddev); 302 SLIST_REMOVE(&sc->head, new_connection, ngd_connection, links); 303 free(new_connection, M_DEVBUF); 304 return(-1); 305 } 306 307 /* point to begin of buffer */ 308 new_connection->loc = 0; 309 new_connection->active_hook = hook; 310 311 SLIST_INSERT_HEAD(&sc->head, new_connection, links); 312 313 return(0); 314 } 315 316 /* 317 * we gave ok to a new hook 318 * now connect 319 */ 320 static int 321 ng_device_connect(hook_p hook) 322 { 323 324 #ifdef NGD_DEBUG 325 printf("%s()\n", __func__); 326 #endif /* NGD_DEBUG */ 327 328 return(0); 329 } 330 331 332 /* 333 * Receive data from hook 334 */ 335 static int 336 ng_device_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 337 { 338 struct ngd_softc *sc = &ngd_softc; 339 struct ngd_connection * connection = NULL; 340 struct ngd_connection * tmp; 341 char *buffer; 342 343 #ifdef NGD_DEBUG 344 printf("%s()\n", __func__); 345 #endif /* NGD_DEBUG */ 346 347 SLIST_FOREACH(tmp, &sc->head, links) { 348 if(tmp->active_hook == hook) { 349 connection = tmp; 350 } 351 } 352 if(connection == NULL) { 353 printf("%s(): connection still NULL, no hook found\n", __func__); 354 return(-1); 355 } 356 357 NG_FREE_META(meta); 358 359 m = m_pullup(m, m->m_len); 360 if(m == NULL) { 361 printf("%s(): ERROR: m_pullup failed\n", __func__); 362 return(-1); 363 } 364 365 buffer = malloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO); 366 if(buffer == NULL) { 367 printf("%s(): ERROR: buffer malloc failed\n", __func__); 368 return(-1); 369 } 370 371 buffer = mtod(m, char *); 372 373 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) { 374 memcpy(connection->readq+connection->loc, buffer, m->m_len); 375 connection->loc += m->m_len; 376 } else 377 printf("%s(): queue full, first read out a bit\n", __func__); 378 379 free(buffer, M_DEVBUF); 380 381 return(0); 382 } 383 384 /* 385 * Removal of the last link destroys the node 386 */ 387 static int 388 ng_device_disconnect(hook_p hook) 389 { 390 struct ngd_softc *sc = &ngd_softc; 391 struct ngd_connection * connection = NULL; 392 struct ngd_connection * tmp; 393 394 #ifdef NGD_DEBUG 395 printf("%s()\n", __func__); 396 #endif /* NGD_DEBUG */ 397 398 SLIST_FOREACH(tmp, &sc->head, links) { 399 if(tmp->active_hook == hook) { 400 connection = tmp; 401 } 402 } 403 if(connection == NULL) { 404 printf("%s(): connection still NULL, no hook found\n", 405 __func__); 406 return(-1); 407 } 408 409 free(connection->readq, M_DEVBUF); 410 411 destroy_dev(connection->ngddev); 412 413 SLIST_REMOVE(&sc->head, connection, ngd_connection, links); 414 415 return(0); 416 } 417 /* 418 * the device is opened 419 */ 420 static int 421 ngdopen(dev_t dev, int flag, int mode, struct thread *td) 422 { 423 424 #ifdef NGD_DEBUG 425 printf("%s()\n", __func__); 426 #endif /* NGD_DEBUG */ 427 428 return(0); 429 } 430 431 /* 432 * the device is closed 433 */ 434 static int 435 ngdclose(dev_t dev, int flag, int mode, struct thread *td) 436 { 437 438 #ifdef NGD_DEBUG 439 printf("%s()\n", __func__); 440 #endif 441 442 return(0); 443 } 444 445 446 /* 447 * process ioctl 448 * 449 * they are translated into netgraph messages and passed on 450 * 451 */ 452 static int 453 ngdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct thread *td) 454 { 455 struct ngd_softc *sc = &ngd_softc; 456 struct ngd_connection * connection = NULL; 457 struct ngd_connection * tmp; 458 int error = 0; 459 struct ng_mesg *msg; 460 struct ngd_param_s * datap; 461 462 #ifdef NGD_DEBUG 463 printf("%s()\n", __func__); 464 #endif /* NGD_DEBUG */ 465 466 SLIST_FOREACH(tmp, &sc->head, links) { 467 if(tmp->ngddev == dev) { 468 connection = tmp; 469 } 470 } 471 if(connection == NULL) { 472 printf("%s(): connection still NULL, no dev found\n", 473 __func__); 474 return(-1); 475 } 476 477 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */ 478 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s), 479 M_NOWAIT); 480 if (msg == NULL) { 481 printf("%s(): msg == NULL\n", __func__); 482 goto nomsg; 483 } 484 485 /* pass the ioctl data into the ->data area */ 486 datap = (struct ngd_param_s *)msg->data; 487 datap->p = addr; 488 489 /*ng_send_msg(node_p here, struct ng_mesg *msg, 490 const char *address, struct ng_mesg **resp); */ 491 error = ng_send_msg(sc->node, msg, 492 NG_HOOK_NAME(connection->active_hook), NULL); 493 if(error) 494 printf("%s(): ng_send_msg() error: %d\n", __func__, error); 495 496 nomsg: 497 498 return(0); 499 } 500 501 502 /* 503 * This function is called when a read(2) is done to our device. 504 * We pass the data available in kernelspace on into userland using 505 * uiomove. 506 */ 507 static int 508 ngdread(dev_t dev, struct uio *uio, int flag) 509 { 510 int ret = 0, amnt; 511 char buffer[uio->uio_resid+1]; 512 struct ngd_softc *sc = &ngd_softc; 513 struct ngd_connection * connection = NULL; 514 struct ngd_connection * tmp; 515 516 #ifdef NGD_DEBUG 517 printf("%s()\n", __func__); 518 #endif /* NGD_DEBUG */ 519 520 SLIST_FOREACH(tmp, &sc->head, links) { 521 if(tmp->ngddev == dev) { 522 connection = tmp; 523 } 524 } 525 if(connection == NULL) { 526 printf("%s(): connection still NULL, no dev found\n", __func__); 527 return(-1); 528 } 529 530 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) { 531 amnt = MIN(uio->uio_resid, connection->loc); 532 533 memcpy(buffer, connection->readq, amnt); 534 memcpy(connection->readq, connection->readq+amnt, 535 connection->loc-amnt); 536 connection->loc -= amnt; 537 538 ret = uiomove((caddr_t)buffer, amnt, uio); 539 if(ret != 0) 540 goto error; 541 542 } 543 return(0); 544 545 error: 546 printf("%s(): uiomove returns error %d\n", __func__, ret); 547 /* do error cleanup here */ 548 return(ret); 549 } 550 551 552 /* 553 * This function is called when our device is written to. 554 * We read the data from userland into our local buffer and pass it on 555 * into the remote hook. 556 * 557 */ 558 static int 559 ngdwrite(dev_t dev, struct uio *uio, int flag) 560 { 561 int ret; 562 int error = 0; 563 struct mbuf *m; 564 char buffer[uio->uio_resid]; 565 int len = uio->uio_resid; 566 struct ngd_softc *sc =& ngd_softc; 567 struct ngd_connection * connection = NULL; 568 struct ngd_connection * tmp; 569 570 #ifdef NGD_DEBUG 571 printf("%s()\n", __func__); 572 #endif /* NGD_DEBUG */ 573 574 SLIST_FOREACH(tmp, &sc->head, links) { 575 if(tmp->ngddev == dev) { 576 connection = tmp; 577 } 578 } 579 580 if(connection == NULL) { 581 printf("%s(): connection still NULL, no dev found\n", __func__); 582 return(-1); 583 } 584 585 if (len > 0) { 586 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0) 587 goto error; 588 } else 589 printf("%s(): len <= 0 : supposed to happen?!\n", __func__); 590 591 m = m_devget(buffer, len, 0, NULL, NULL); 592 593 NG_SEND_DATA_ONLY(error, connection->active_hook, m); 594 595 return(0); 596 597 error: 598 /* do error cleanup here */ 599 printf("%s(): uiomove returned err: %d\n", __func__, ret); 600 601 return(ret); 602 } 603 604 /* 605 * we are being polled/selected 606 * check if there is data available for read 607 */ 608 static int 609 ngdpoll(dev_t dev, int events, struct thread *td) 610 { 611 int revents = 0; 612 struct ngd_softc *sc = &ngd_softc; 613 struct ngd_connection * connection = NULL; 614 struct ngd_connection * tmp; 615 616 617 if (events & (POLLIN | POLLRDNORM)) { 618 /* get the connection we have to know the loc from */ 619 SLIST_FOREACH(tmp, &sc->head, links) { 620 if(tmp->ngddev == dev) { 621 connection = tmp; 622 } 623 } 624 if(connection == NULL) { 625 printf("%s(): ERROR: connection still NULL, " 626 "no dev found\n", __func__); 627 return(-1); 628 } 629 630 if (connection->loc > 0) 631 revents |= events & (POLLIN | POLLRDNORM); 632 } 633 634 return(revents); 635 } 636