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 * $FreeBSD$
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_DONTWAIT, 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