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: releng/5.0/sys/netgraph/ng_device.c 98402 2002-06-18 21:32:33Z julian $
32 *
33 */
34
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/mbuf.h>
39 #include <sys/uio.h>
40 #include <sys/queue.h>
41 #include <sys/malloc.h>
42 #include <sys/conf.h>
43 #include <sys/poll.h>
44 #include <sys/ioccom.h>
45
46 #include <netgraph/ng_message.h>
47 #include <netgraph/netgraph.h>
48
49 #include "ng_device.h"
50
51 /* turn this on for verbose messages */
52 #define NGD_DEBUG
53
54 /* Netgraph methods */
55 static ng_constructor_t ng_device_cons;
56 static ng_rcvmsg_t ng_device_rcvmsg;
57 static ng_newhook_t ng_device_newhook;
58 static ng_connect_t ng_device_connect;
59 static ng_rcvdata_t ng_device_rcvdata;
60 static ng_disconnect_t ng_device_disconnect;
61 static int ng_device_mod_event(module_t mod, int event, void *data);
62
63 static int ng_device_init(void);
64 static int get_free_unit(void);
65
66 /* Netgraph type */
67 static struct ng_type typestruct = {
68 NG_ABI_VERSION, /* version */
69 NG_DEVICE_NODE_TYPE, /* name */
70 ng_device_mod_event, /* modevent */
71 ng_device_cons, /* constructor */
72 ng_device_rcvmsg, /* receive msg */
73 NULL, /* shutdown */
74 ng_device_newhook, /* newhook */
75 NULL, /* findhook */
76 ng_device_connect, /* connect */
77 ng_device_rcvdata, /* receive data */
78 ng_device_disconnect, /* disconnect */
79 NULL
80 };
81 NETGRAPH_INIT(device, &typestruct);
82
83 /* per hook data */
84 struct ngd_connection {
85 SLIST_ENTRY(ngd_connection) links;
86
87 dev_t ngddev;
88 struct ng_hook *active_hook;
89 char *readq;
90 int loc;
91 int unit;
92 };
93
94 /* global data */
95 struct ngd_softc {
96 SLIST_HEAD(, ngd_connection) head;
97
98 node_p node;
99 char nodename[NG_NODELEN + 1];
100 } ngd_softc;
101
102 /* helper definition */
103 #define MIN(a, b) ((a) < (b) ? (a) : (b))
104
105 /* the per connection receiving queue maximum */
106 #define NGD_QUEUE_SIZE (1024*10)
107
108 /* Maximum number of NGD devices */
109 #define MAX_NGD 25 /* should be more than enough for now */
110
111 static d_close_t ngdclose;
112 static d_open_t ngdopen;
113 static d_read_t ngdread;
114 static d_write_t ngdwrite;
115 static d_ioctl_t ngdioctl;
116 static d_poll_t ngdpoll;
117
118 #define NGD_CDEV_MAJOR 20
119 static struct cdevsw ngd_cdevsw = {
120 /* open */ ngdopen,
121 /* close */ ngdclose,
122 /* read */ ngdread,
123 /* write */ ngdwrite,
124 /* ioctl */ ngdioctl,
125 /* poll */ ngdpoll,
126 /* mmap */ nommap,
127 /* strategy */ nostrategy,
128 /* name */ "ngd",
129 /* maj */ NGD_CDEV_MAJOR,
130 /* dump */ nodump,
131 /* psize */ nopsize,
132 /* flags */ 0,
133 };
134
135 /*
136 * this holds all the stuff that should be done at load time
137 */
138 static int
139 ng_device_mod_event(module_t mod, int event, void *data)
140 {
141 int error = 0;
142
143 #ifdef NGD_DEBUG
144 printf("%s()\n",__func__);
145 #endif /* NGD_DEBUG */
146
147 switch (event) {
148 case MOD_LOAD:
149
150 ng_device_init();
151 break;
152
153 case MOD_UNLOAD:
154 /* XXX do we need to do something specific ? */
155 /* ng_device_breakdown */
156 break;
157
158 default:
159 error = EOPNOTSUPP;
160 break;
161 }
162
163 return(error);
164 }
165
166
167 static int
168 ng_device_init()
169 {
170 struct ngd_softc *sc = &ngd_softc;
171
172 #ifdef NGD_DEBUG
173 printf("%s()\n",__func__);
174 #endif /* NGD_DEBUG */
175
176 SLIST_INIT(&sc->head);
177
178 if (ng_make_node_common(&typestruct, &sc->node) != 0) {
179 printf("%s(): ng_make_node_common failed\n",__func__);
180 return(ENXIO);
181 }
182 sprintf(sc->nodename, "%s", NG_DEVICE_NODE_TYPE);
183 if (ng_name_node(sc->node, sc->nodename)) {
184 NG_NODE_UNREF(sc->node); /* make it go away again */
185 printf("%s(): ng_name_node failed\n",__func__);
186 return(ENXIO);
187 }
188 NG_NODE_SET_PRIVATE(sc->node, sc);
189
190 return(0);
191 }
192
193 /*
194 * don't allow to be created, only the device can do that
195 */
196 static int
197 ng_device_cons(node_p node)
198 {
199
200 #ifdef NGD_DEBUG
201 printf("%s()\n",__func__);
202 #endif /* NGD_DEBUG */
203
204 return(EINVAL);
205 }
206
207 /*
208 * Receive control message. We just bounce it back as a reply.
209 */
210 static int
211 ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook)
212 {
213 struct ngd_softc *sc = &ngd_softc;
214 struct ng_mesg *msg;
215 int error = 0;
216 struct ngd_connection * connection = NULL;
217 struct ngd_connection *tmp = NULL;
218
219 #ifdef NGD_DEBUG
220 printf("%s()\n",__func__);
221 #endif /* NGD_DEBUG */
222
223 NGI_GET_MSG(item, msg);
224
225 SLIST_FOREACH(tmp,&sc->head,links) {
226 if(tmp->active_hook == lasthook) {
227 connection = tmp;
228 }
229 }
230 if(connection == NULL) {
231 printf("%s(): connection is still NULL, no hook found\n",__func__);
232 return(-1);
233 }
234
235 return(error);
236 }
237
238 static int
239 get_free_unit()
240 {
241 struct ngd_connection *tmp = NULL;
242 struct ngd_softc *sc = &ngd_softc;
243 int n = 0;
244 int unit = -1;
245
246 #ifdef NGD_DEBUG
247 printf("%s()\n",__func__);
248 #endif /* NGD_DEBUG */
249
250 /* When there is no list yet, the first device unit is always 0. */
251 if SLIST_EMPTY(&sc->head) {
252 unit = 0;
253 return(unit);
254 }
255
256 /* Just do a brute force loop to find the first free unit that is
257 * smaller than MAX_NGD.
258 * Set MAX_NGD to a large value, doesn't impact performance.
259 */
260 for(n = 0;n<MAX_NGD && unit == -1;n++) {
261 SLIST_FOREACH(tmp,&sc->head,links) {
262
263 if(tmp->unit == n) {
264 unit = -1;
265 break;
266 }
267 unit = n;
268 }
269 }
270
271 return(unit);
272 }
273
274 /*
275 * incoming hook
276 */
277 static int
278 ng_device_newhook(node_p node, hook_p hook, const char *name)
279 {
280 struct ngd_softc *sc = &ngd_softc;
281 struct ngd_connection * new_connection = NULL;
282
283 #ifdef NGD_DEBUG
284 printf("%s()\n",__func__);
285 #endif /* NGD_DEBUG */
286
287 new_connection = malloc(sizeof(struct ngd_connection), M_DEVBUF, M_NOWAIT);
288 if(new_connection == NULL) {
289 printf("%s(): ERROR: new_connection == NULL\n",__func__);
290 return(-1);
291 }
292
293 new_connection->unit = get_free_unit();
294 if(new_connection->unit<0) {
295 printf("%s: No free unit found by get_free_unit(), "
296 "increas MAX_NGD\n",__func__);
297 return(-1);
298 }
299 new_connection->ngddev = make_dev(&ngd_cdevsw, new_connection->unit, 0, 0,0600,"ngd%d",new_connection->unit);
300 if(new_connection->ngddev == NULL) {
301 printf("%s(): make_dev failed\n",__func__);
302 return(-1);
303 }
304
305 new_connection->readq = malloc(sizeof(char)*NGD_QUEUE_SIZE, M_DEVBUF, M_NOWAIT | M_ZERO);
306 if(new_connection->readq == NULL) {
307 printf("%s(): readq malloc failed\n",__func__);
308 return(-1);
309 }
310
311 /* point to begin of buffer */
312 new_connection->loc = 0;
313 new_connection->active_hook = hook;
314
315 SLIST_INSERT_HEAD(&sc->head, new_connection, links);
316
317 return(0);
318 }
319
320 /*
321 * we gave ok to a new hook
322 * now connect
323 */
324 static int
325 ng_device_connect(hook_p hook)
326 {
327
328 #ifdef NGD_DEBUG
329 printf("%s()\n",__func__);
330 #endif /* NGD_DEBUG */
331
332 return(0);
333 }
334
335
336 /*
337 * Receive data from hook
338 */
339 static int
340 ng_device_rcvdata(hook_p hook, item_p item)
341 {
342 struct mbuf *m;
343 struct ngd_softc *sc = &ngd_softc;
344 struct ngd_connection * connection = NULL;
345 struct ngd_connection * tmp;
346 char *buffer;
347
348 #ifdef NGD_DEBUG
349 printf("%s()\n",__func__);
350 #endif /* NGD_DEBUG */
351
352 SLIST_FOREACH(tmp,&sc->head,links) {
353 if(tmp->active_hook == hook) {
354 connection = tmp;
355 }
356 }
357 if(connection == NULL) {
358 printf("%s(): connection is still NULL, no hook found\n",__func__);
359 return(-1);
360 }
361
362 NGI_GET_M(item, m);
363 NG_FREE_ITEM(item);
364
365 m = m_pullup(m,m->m_len);
366 if(m == NULL) {
367 printf("%s(): ERROR: m_pullup failed\n",__func__);
368 return(-1);
369 }
370
371 buffer = malloc(sizeof(char)*m->m_len, M_DEVBUF, M_NOWAIT | M_ZERO);
372 if(buffer == NULL) {
373 printf("%s(): ERROR: buffer malloc failed\n",__func__);
374 return(-1);
375 }
376
377 buffer = mtod(m,char *);
378
379 if( (connection->loc+m->m_len) < NGD_QUEUE_SIZE) {
380 memcpy(connection->readq+connection->loc, buffer, m->m_len);
381 connection->loc += m->m_len;
382 } else
383 printf("%s(): queue full, first read out a bit\n",__func__);
384
385 free(buffer,M_DEVBUF);
386
387 return(0);
388 }
389
390 /*
391 * Removal of the last link destroys the node
392 */
393 static int
394 ng_device_disconnect(hook_p hook)
395 {
396 struct ngd_softc *sc = &ngd_softc;
397 struct ngd_connection * connection = NULL;
398 struct ngd_connection * tmp;
399
400 #ifdef NGD_DEBUG
401 printf("%s()\n",__func__);
402 #endif /* NGD_DEBUG */
403
404 SLIST_FOREACH(tmp,&sc->head,links) {
405 if(tmp->active_hook == hook) {
406 connection = tmp;
407 }
408 }
409 if(connection == NULL) {
410 printf("%s(): connection is still NULL, no hook found\n",__func__);
411 return(-1);
412 }
413
414 free(connection->readq,M_DEVBUF);
415
416 destroy_dev(connection->ngddev);
417
418 SLIST_REMOVE(&sc->head,connection,ngd_connection,links);
419
420 return(0);
421 }
422 /*
423 * the device is opened
424 */
425 static int
426 ngdopen(dev_t dev, int flag, int mode, struct thread *td)
427 {
428
429 #ifdef NGD_DEBUG
430 printf("%s()\n",__func__);
431 #endif /* NGD_DEBUG */
432
433 return(0);
434 }
435
436 /*
437 * the device is closed
438 */
439 static int
440 ngdclose(dev_t dev, int flag, int mode, struct thread *td)
441 {
442
443 #ifdef NGD_DEBUG
444 printf("%s()\n",__func__);
445 #endif
446
447 return(0);
448 }
449
450
451 /*
452 * process ioctl
453 *
454 * they are translated into netgraph messages and passed on
455 *
456 */
457 static int
458 ngdioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
459 {
460 struct ngd_softc *sc = &ngd_softc;
461 struct ngd_connection * connection = NULL;
462 struct ngd_connection * tmp;
463 int error = 0;
464 struct ng_mesg *msg;
465 struct ngd_param_s * datap;
466
467 #ifdef NGD_DEBUG
468 printf("%s()\n",__func__);
469 #endif /* NGD_DEBUG */
470
471 SLIST_FOREACH(tmp,&sc->head,links) {
472 if(tmp->ngddev == dev) {
473 connection = tmp;
474 }
475 }
476 if(connection == NULL) {
477 printf("%s(): connection is still NULL, no dev found\n",__func__);
478 return(-1);
479 }
480
481 /* NG_MKMESSAGE(msg, cookie, cmdid, len, how) */
482 NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
483 M_NOWAIT);
484 if (msg == NULL) {
485 printf("%s(): msg == NULL\n",__func__);
486 goto nomsg;
487 }
488
489 /* pass the ioctl data into the ->data area */
490 datap = (struct ngd_param_s *)msg->data;
491 datap->p = addr;
492
493 /* NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr) */
494 NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, NULL);
495 if(error)
496 printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error);
497
498 nomsg:
499
500 return(0);
501 }
502
503
504 /*
505 * This function is called when a read(2) is done to our device.
506 * We pass the data available in kernelspace on into userland using
507 * uiomove.
508 */
509 static int
510 ngdread(dev_t dev, struct uio *uio, int flag)
511 {
512 int ret = 0, amnt;
513 char buffer[uio->uio_resid+1];
514 struct ngd_softc *sc = &ngd_softc;
515 struct ngd_connection * connection = NULL;
516 struct ngd_connection * tmp;
517
518 #ifdef NGD_DEBUG
519 printf("%s()\n",__func__);
520 #endif /* NGD_DEBUG */
521
522 SLIST_FOREACH(tmp,&sc->head,links) {
523 if(tmp->ngddev == dev) {
524 connection = tmp;
525 }
526 }
527 if(connection == NULL) {
528 printf("%s(): connection is still NULL, no dev found\n",__func__);
529 return(-1);
530 }
531
532 while ( ( uio->uio_resid > 0 ) && ( connection->loc > 0 ) ) {
533 amnt = MIN(uio->uio_resid,connection->loc);
534
535 memcpy(buffer,connection->readq, amnt);
536 memcpy(connection->readq, connection->readq+amnt,
537 connection->loc-amnt);
538 connection->loc -= amnt;
539
540 ret = uiomove((caddr_t)buffer, amnt, uio);
541 if(ret != 0)
542 goto error;
543
544 }
545 return(0);
546
547 error:
548 printf("%s(): uiomove returns error %d\n",__func__,ret);
549 /* do error cleanup here */
550 return(ret);
551 }
552
553
554 /*
555 * This function is called when our device is written to.
556 * We read the data from userland into our local buffer and pass it on
557 * into the remote hook.
558 *
559 */
560 static int
561 ngdwrite(dev_t dev, struct uio *uio, int flag)
562 {
563 int ret;
564 int error = 0;
565 struct mbuf *m;
566 char buffer[uio->uio_resid];
567 int len = uio->uio_resid;
568 struct ngd_softc *sc =& ngd_softc;
569 struct ngd_connection * connection = NULL;
570 struct ngd_connection * tmp;
571
572 #ifdef NGD_DEBUG
573 printf("%s()\n",__func__);
574 #endif /* NGD_DEBUG */
575
576 SLIST_FOREACH(tmp,&sc->head,links) {
577 if(tmp->ngddev == dev) {
578 connection = tmp;
579 }
580 }
581
582 if(connection == NULL) {
583 printf("%s(): connection is still NULL, no dev found\n",__func__);
584 return(-1);
585 }
586
587 if (len > 0) {
588 if ((ret = uiomove((caddr_t)buffer, len, uio)) != 0)
589 goto error;
590 } else
591 printf("%s(): len <= 0 : is this supposed to happen?!\n",__func__);
592
593 m = m_devget(buffer,len,0,NULL,NULL);
594
595 NG_SEND_DATA_ONLY(error,connection->active_hook,m);
596
597 return(0);
598
599 error:
600 /* do error cleanup here */
601 printf("%s(): uiomove returned err: %d\n",__func__,ret);
602
603 return(ret);
604 }
605
606 /*
607 * we are being polled/selected
608 * check if there is data available for read
609 */
610 static int
611 ngdpoll(dev_t dev, int events, struct thread *td)
612 {
613 int revents = 0;
614 struct ngd_softc *sc = &ngd_softc;
615 struct ngd_connection * connection = NULL;
616 struct ngd_connection * tmp;
617
618
619 if (events & (POLLIN | POLLRDNORM)) {
620 /* get the connection we have to know the loc from */
621 SLIST_FOREACH(tmp,&sc->head,links) {
622 if(tmp->ngddev == dev) {
623 connection = tmp;
624 }
625 }
626 if(connection == NULL) {
627 printf("%s(): ERROR: connection is still NULL,"
628 "no dev found\n",__func__);
629 return(-1);
630 }
631
632 if (connection->loc > 0)
633 revents |= events & (POLLIN | POLLRDNORM);
634 }
635
636 return(revents);
637 }
Cache object: 2c2f34423720c3816d67424c49f109d9
|