1/*
2 * ng_h4.c
3 */
4
5/*-
6 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
7 *
8 * Copyright (c) 2001-2002 Maksim Yevmenkin <m_evmenkin@yahoo.com>
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * $Id: ng_h4.c,v 1.10 2005/10/31 17:57:43 max Exp $
33 * $FreeBSD$
34 *
35 * Based on:
36 * ---------
37 *
38 * FreeBSD: src/sys/netgraph/ng_tty.c
39 * Author: Archie Cobbs <archie@freebsd.org>
40 *
41 */
42
43#include <sys/param.h>
44#include <sys/systm.h>
45#include <sys/kernel.h>
46#include <sys/conf.h>
47#include <sys/endian.h>
48#include <sys/errno.h>
49#include <sys/fcntl.h>
50#include <sys/ioccom.h>
51#include <sys/malloc.h>
52#include <sys/mbuf.h>
53#include <sys/priv.h>
54#include <sys/socket.h>
55#include <sys/tty.h>
56#include <sys/ttycom.h>
57#include <net/if.h>
58#include <net/if_var.h>
59#include <netgraph/ng_message.h>
60#include <netgraph/netgraph.h>
61#include <netgraph/ng_parse.h>
62#include <netgraph/bluetooth/include/ng_bluetooth.h>
63#include <netgraph/bluetooth/include/ng_hci.h>
64#include <netgraph/bluetooth/include/ng_h4.h>
65#include <netgraph/bluetooth/drivers/h4/ng_h4_var.h>
66#include <netgraph/bluetooth/drivers/h4/ng_h4_prse.h>
67
68/*****************************************************************************
69 *****************************************************************************
70 ** This node implements a Bluetooth HCI UART transport layer as per chapter
71 ** H4 of the Bluetooth Specification Book v1.1. It is a terminal line
72 ** discipline that is also a netgraph node. Installing this line discipline
73 ** on a terminal device instantiates a new netgraph node of this type, which
74 ** allows access to the device via the "hook" hook of the node.
75 **
76 ** Once the line discipline is installed, you can find out the name of the
77 ** corresponding netgraph node via a NGIOCGINFO ioctl().
78 *****************************************************************************
79 *****************************************************************************/
80
81/* MALLOC define */
82#ifndef NG_SEPARATE_MALLOC
83MALLOC_DEFINE(M_NETGRAPH_H4, "netgraph_h4", "Netgraph Bluetooth H4 node");
84#else
85#define M_NETGRAPH_H4 M_NETGRAPH
86#endif /* NG_SEPARATE_MALLOC */
87
88/* Line discipline methods */
89static int	ng_h4_open	(struct cdev *, struct tty *);
90static int	ng_h4_close	(struct tty *, int);
91static int	ng_h4_read	(struct tty *, struct uio *, int);
92static int	ng_h4_write	(struct tty *, struct uio *, int);
93static int	ng_h4_input	(int, struct tty *);
94static int	ng_h4_start	(struct tty *);
95static int	ng_h4_ioctl	(struct tty *, u_long, caddr_t,
96					int, struct thread *);
97
98/* Line discipline descriptor */
99static struct linesw		ng_h4_disc = {
100	ng_h4_open,		/* open */
101	ng_h4_close,		/* close */
102	ng_h4_read,		/* read */
103	ng_h4_write,		/* write */
104	ng_h4_ioctl,		/* ioctl */
105	ng_h4_input,		/* input */
106	ng_h4_start,		/* start */
107	ttymodem		/* modem */
108};
109
110/* Netgraph methods */
111static ng_constructor_t		ng_h4_constructor;
112static ng_rcvmsg_t		ng_h4_rcvmsg;
113static ng_shutdown_t		ng_h4_shutdown;
114static ng_newhook_t		ng_h4_newhook;
115static ng_connect_t		ng_h4_connect;
116static ng_rcvdata_t		ng_h4_rcvdata;
117static ng_disconnect_t		ng_h4_disconnect;
118
119/* Other stuff */
120static void	ng_h4_process_timeout	(node_p, hook_p, void *, int);
121static int	ng_h4_mod_event		(module_t, int, void *);
122
123/* Netgraph node type descriptor */
124static struct ng_type		typestruct = {
125	.version =	NG_ABI_VERSION,
126	.name =		NG_H4_NODE_TYPE,
127	.mod_event =	ng_h4_mod_event,
128	.constructor =	ng_h4_constructor,
129	.rcvmsg =	ng_h4_rcvmsg,
130	.shutdown =	ng_h4_shutdown,
131	.newhook =	ng_h4_newhook,
132	.connect =	ng_h4_connect,
133	.rcvdata =	ng_h4_rcvdata,
134	.disconnect =	ng_h4_disconnect,
135	.cmdlist =	ng_h4_cmdlist
136};
137NETGRAPH_INIT(h4, &typestruct);
138MODULE_VERSION(ng_h4, NG_BLUETOOTH_VERSION);
139
140static int	ng_h4_node = 0;
141
142/*****************************************************************************
143 *****************************************************************************
144 **			    Line discipline methods
145 *****************************************************************************
146 *****************************************************************************/
147
148/*
149 * Set our line discipline on the tty.
150 */
151
152static int
153ng_h4_open(struct cdev *dev, struct tty *tp)
154{
155	struct thread	*td = curthread;
156	char		 name[NG_NODESIZ];
157	ng_h4_info_p	 sc = NULL;
158	int		 error;
159
160	/* Super-user only */
161	error = priv_check(td, PRIV_NETGRAPH_TTY); /* XXX */
162	if (error != 0)
163		return (error);
164
165	/* Initialize private struct */
166	sc = malloc(sizeof(*sc), M_NETGRAPH_H4, M_NOWAIT|M_ZERO);
167	if (sc == NULL)
168		return (ENOMEM);
169
170	sc->tp = tp;
171	sc->debug = NG_H4_WARN_LEVEL;
172
173	sc->state = NG_H4_W4_PKT_IND;
174	sc->want = 1;
175	sc->got = 0;
176
177	mtx_init(&sc->outq.ifq_mtx, "ng_h4 node+queue", NULL, MTX_DEF);
178	IFQ_SET_MAXLEN(&sc->outq, NG_H4_DEFAULTQLEN);
179	ng_callout_init(&sc->timo);
180
181	NG_H4_LOCK(sc);
182
183	/* Setup netgraph node */
184	error = ng_make_node_common(&typestruct, &sc->node);
185	if (error != 0) {
186		NG_H4_UNLOCK(sc);
187
188		printf("%s: Unable to create new node!\n", __func__);
189
190		mtx_destroy(&sc->outq.ifq_mtx);
191		bzero(sc, sizeof(*sc));
192		free(sc, M_NETGRAPH_H4);
193
194		return (error);
195	}
196
197	/* Assign node its name */
198	snprintf(name, sizeof(name), "%s%d", typestruct.name, ng_h4_node ++);
199
200	error = ng_name_node(sc->node, name);
201	if (error != 0) {
202		NG_H4_UNLOCK(sc);
203
204		printf("%s: %s - node name exists?\n", __func__, name);
205
206		NG_NODE_UNREF(sc->node);
207		mtx_destroy(&sc->outq.ifq_mtx);
208		bzero(sc, sizeof(*sc));
209		free(sc, M_NETGRAPH_H4);
210
211		return (error);
212	}
213
214	/* Set back pointers */
215	NG_NODE_SET_PRIVATE(sc->node, sc);
216	tp->t_lsc = (caddr_t) sc;
217
218	/* The node has to be a WRITER because data can change node status */
219	NG_NODE_FORCE_WRITER(sc->node);
220
221	/*
222	 * Pre-allocate cblocks to the an appropriate amount.
223	 * I'm not sure what is appropriate.
224	 */
225
226	ttyflush(tp, FREAD | FWRITE);
227	clist_alloc_cblocks(&tp->t_canq, 0, 0);
228	clist_alloc_cblocks(&tp->t_rawq, 0, 0);
229	clist_alloc_cblocks(&tp->t_outq,
230		MLEN + NG_H4_HIWATER, MLEN + NG_H4_HIWATER);
231
232	NG_H4_UNLOCK(sc);
233
234	return (error);
235} /* ng_h4_open */
236
237/*
238 * Line specific close routine, called from device close routine
239 * and from ttioctl. This causes the node to be destroyed as well.
240 */
241
242static int
243ng_h4_close(struct tty *tp, int flag)
244{
245	ng_h4_info_p	sc = (ng_h4_info_p) tp->t_lsc;
246
247	ttyflush(tp, FREAD | FWRITE);
248	clist_free_cblocks(&tp->t_outq);
249
250	if (sc != NULL) {
251		NG_H4_LOCK(sc);
252
253		if (callout_pending(&sc->timo))
254			ng_uncallout(&sc->timo, sc->node);
255
256		tp->t_lsc = NULL;
257		sc->dying = 1;
258
259		NG_H4_UNLOCK(sc);
260
261		ng_rmnode_self(sc->node);
262	}
263
264	return (0);
265} /* ng_h4_close */
266
267/*
268 * Once the device has been turned into a node, we don't allow reading.
269 */
270
271static int
272ng_h4_read(struct tty *tp, struct uio *uio, int flag)
273{
274	return (EIO);
275} /* ng_h4_read */
276
277/*
278 * Once the device has been turned into a node, we don't allow writing.
279 */
280
281static int
282ng_h4_write(struct tty *tp, struct uio *uio, int flag)
283{
284	return (EIO);
285} /* ng_h4_write */
286
287/*
288 * We implement the NGIOCGINFO ioctl() defined in ng_message.h.
289 */
290
291static int
292ng_h4_ioctl(struct tty *tp, u_long cmd, caddr_t data, int flag,
293		struct thread *td)
294{
295	ng_h4_info_p	sc = (ng_h4_info_p) tp->t_lsc;
296	int		error = 0;
297
298	if (sc == NULL)
299		return (ENXIO);
300
301	NG_H4_LOCK(sc);
302
303	switch (cmd) {
304	case NGIOCGINFO:
305#undef	NI
306#define NI(x)	((struct nodeinfo *)(x))
307
308		bzero(data, sizeof(*NI(data)));
309
310		if (NG_NODE_HAS_NAME(sc->node))
311			strncpy(NI(data)->name, NG_NODE_NAME(sc->node),
312				sizeof(NI(data)->name) - 1);
313
314		strncpy(NI(data)->type, sc->node->nd_type->name,
315			sizeof(NI(data)->type) - 1);
316
317		NI(data)->id = (u_int32_t) ng_node2ID(sc->node);
318		NI(data)->hooks = NG_NODE_NUMHOOKS(sc->node);
319		break;
320
321	default:
322		error = ENOIOCTL;
323		break;
324	}
325
326	NG_H4_UNLOCK(sc);
327
328	return (error);
329} /* ng_h4_ioctl */
330
331/*
332 * Receive data coming from the device. We get one character at a time, which
333 * is kindof silly.
334 */
335
336static int
337ng_h4_input(int c, struct tty *tp)
338{
339	ng_h4_info_p	sc = (ng_h4_info_p) tp->t_lsc;
340
341	if (sc == NULL || tp != sc->tp ||
342	    sc->node == NULL || NG_NODE_NOT_VALID(sc->node))
343		return (0);
344
345	NG_H4_LOCK(sc);
346
347	/* Check for error conditions */
348	if ((tp->t_state & TS_CONNECTED) == 0) {
349		NG_H4_INFO("%s: %s - no carrier\n", __func__,
350			NG_NODE_NAME(sc->node));
351
352		sc->state = NG_H4_W4_PKT_IND;
353		sc->want = 1;
354		sc->got = 0;
355
356		NG_H4_UNLOCK(sc);
357
358		return (0); /* XXX Loss of synchronization here! */
359	}
360
361	/* Check for framing error or overrun on this char */
362	if (c & TTY_ERRORMASK) {
363		NG_H4_ERR("%s: %s - line error %#x, c=%#x\n", __func__,
364			NG_NODE_NAME(sc->node), c & TTY_ERRORMASK,
365			c & TTY_CHARMASK);
366
367		NG_H4_STAT_IERROR(sc->stat);
368
369		sc->state = NG_H4_W4_PKT_IND;
370		sc->want = 1;
371		sc->got = 0;
372
373		NG_H4_UNLOCK(sc);
374
375		return (0); /* XXX Loss of synchronization here! */
376	}
377
378	NG_H4_STAT_BYTES_RECV(sc->stat, 1);
379
380	/* Append char to mbuf */
381	if (sc->got >= sizeof(sc->ibuf)) {
382		NG_H4_ALERT("%s: %s - input buffer overflow, c=%#x, got=%d\n",
383			__func__, NG_NODE_NAME(sc->node), c & TTY_CHARMASK,
384			sc->got);
385
386		NG_H4_STAT_IERROR(sc->stat);
387
388		sc->state = NG_H4_W4_PKT_IND;
389		sc->want = 1;
390		sc->got = 0;
391
392		NG_H4_UNLOCK(sc);
393
394		return (0); /* XXX Loss of synchronization here! */
395	}
396
397	sc->ibuf[sc->got ++] = (c & TTY_CHARMASK);
398
399	NG_H4_INFO("%s: %s - got char %#x, want=%d, got=%d\n", __func__,
400		NG_NODE_NAME(sc->node), c, sc->want, sc->got);
401
402	if (sc->got < sc->want) {
403		NG_H4_UNLOCK(sc);
404
405		return (0); /* Wait for more */
406	}
407
408	switch (sc->state) {
409	/* Got packet indicator */
410	case NG_H4_W4_PKT_IND:
411		NG_H4_INFO("%s: %s - got packet indicator %#x\n", __func__,
412			NG_NODE_NAME(sc->node), sc->ibuf[0]);
413
414		sc->state = NG_H4_W4_PKT_HDR;
415
416		/*
417		 * Since packet indicator included in the packet header
418		 * just set sc->want to sizeof(packet header).
419		 */
420
421		switch (sc->ibuf[0]) {
422		case NG_HCI_ACL_DATA_PKT:
423			sc->want = sizeof(ng_hci_acldata_pkt_t);
424			break;
425
426		case NG_HCI_SCO_DATA_PKT:
427			sc->want = sizeof(ng_hci_scodata_pkt_t);
428			break;
429
430		case NG_HCI_EVENT_PKT:
431			sc->want = sizeof(ng_hci_event_pkt_t);
432			break;
433
434		default:
435			NG_H4_WARN("%s: %s - ignoring unknown packet " \
436				"type=%#x\n", __func__, NG_NODE_NAME(sc->node),
437				sc->ibuf[0]);
438
439			NG_H4_STAT_IERROR(sc->stat);
440
441			sc->state = NG_H4_W4_PKT_IND;
442			sc->want = 1;
443			sc->got = 0;
444			break;
445		}
446		break;
447
448	/* Got packet header */
449	case NG_H4_W4_PKT_HDR:
450		sc->state = NG_H4_W4_PKT_DATA;
451
452		switch (sc->ibuf[0]) {
453		case NG_HCI_ACL_DATA_PKT:
454			c = le16toh(((ng_hci_acldata_pkt_t *)
455				(sc->ibuf))->length);
456			break;
457
458		case NG_HCI_SCO_DATA_PKT:
459			c = ((ng_hci_scodata_pkt_t *)(sc->ibuf))->length;
460			break;
461
462		case NG_HCI_EVENT_PKT:
463			c = ((ng_hci_event_pkt_t *)(sc->ibuf))->length;
464			break;
465
466		default:
467			KASSERT((0), ("Invalid packet type=%#x\n",
468				sc->ibuf[0]));
469			break;
470		}
471
472		NG_H4_INFO("%s: %s - got packet header, packet type=%#x, " \
473			"packet size=%d, payload size=%d\n", __func__,
474			NG_NODE_NAME(sc->node), sc->ibuf[0], sc->got, c);
475
476		if (c > 0) {
477			sc->want += c;
478
479			/*
480			 * Try to prevent possible buffer overrun
481			 *
482			 * XXX I'm *really* confused here. It turns out
483			 * that Xircom card sends us packets with length
484			 * greater then 512 bytes! This is greater then
485			 * our old receive buffer (ibuf) size. In the same
486			 * time the card demands from us *not* to send
487			 * packets greater then 192 bytes. Weird! How the
488			 * hell i should know how big *receive* buffer
489			 * should be? For now increase receiving buffer
490			 * size to 1K and add the following check.
491			 */
492
493			if (sc->want >= sizeof(sc->ibuf)) {
494				int	b;
495
496				NG_H4_ALERT("%s: %s - packet too big for " \
497					"buffer, type=%#x, got=%d, want=%d, " \
498					"length=%d\n", __func__,
499					NG_NODE_NAME(sc->node), sc->ibuf[0],
500					sc->got, sc->want, c);
501
502				NG_H4_ALERT("Packet header:\n");
503				for (b = 0; b < sc->got; b++)
504					NG_H4_ALERT("%#x ", sc->ibuf[b]);
505				NG_H4_ALERT("\n");
506
507				/* Reset state */
508				NG_H4_STAT_IERROR(sc->stat);
509
510				sc->state = NG_H4_W4_PKT_IND;
511				sc->want = 1;
512				sc->got = 0;
513			}
514
515			break;
516		}
517
518		/* else FALLTHROUGH and deliver frame */
519		/* XXX Is this true? Should we deliver empty frame? */
520
521	/* Got packet data */
522	case NG_H4_W4_PKT_DATA:
523		NG_H4_INFO("%s: %s - got full packet, packet type=%#x, " \
524			"packet size=%d\n", __func__,
525			NG_NODE_NAME(sc->node), sc->ibuf[0], sc->got);
526
527		if (sc->hook != NULL && NG_HOOK_IS_VALID(sc->hook)) {
528			struct mbuf	*m = NULL;
529
530			MGETHDR(m, M_NOWAIT, MT_DATA);
531			if (m != NULL) {
532				m->m_pkthdr.len = 0;
533
534				/* XXX m_copyback() is stupid */
535				m->m_len = min(MHLEN, sc->got);
536
537				m_copyback(m, 0, sc->got, sc->ibuf);
538				NG_SEND_DATA_ONLY(c, sc->hook, m);
539			} else {
540				NG_H4_ERR("%s: %s - could not get mbuf\n",
541					__func__, NG_NODE_NAME(sc->node));
542
543				NG_H4_STAT_IERROR(sc->stat);
544			}
545		}
546
547		sc->state = NG_H4_W4_PKT_IND;
548		sc->want = 1;
549		sc->got = 0;
550
551		NG_H4_STAT_PCKTS_RECV(sc->stat);
552		break;
553
554	default:
555		KASSERT((0), ("Invalid H4 node state=%d", sc->state));
556		break;
557	}
558
559	NG_H4_UNLOCK(sc);
560
561	return (0);
562} /* ng_h4_input */
563
564/*
565 * This is called when the device driver is ready for more output. Called from
566 * tty system.
567 */
568
569static int
570ng_h4_start(struct tty *tp)
571{
572	ng_h4_info_p	 sc = (ng_h4_info_p) tp->t_lsc;
573	struct mbuf	*m = NULL;
574	int		 size;
575
576	if (sc == NULL || tp != sc->tp ||
577	    sc->node == NULL || NG_NODE_NOT_VALID(sc->node))
578		return (0);
579
580#if 0
581	while (tp->t_outq.c_cc < NG_H4_HIWATER) { /* XXX 2.2 specific ? */
582#else
583	while (1) {
584#endif
585		/* Remove first mbuf from queue */
586		IF_DEQUEUE(&sc->outq, m);
587		if (m == NULL)
588			break;
589
590		/* Send as much of it as possible */
591		while (m != NULL) {
592			size = m->m_len - b_to_q(mtod(m, u_char *),
593					m->m_len, &tp->t_outq);
594
595			NG_H4_LOCK(sc);
596			NG_H4_STAT_BYTES_SENT(sc->stat, size);
597			NG_H4_UNLOCK(sc);
598
599			m->m_data += size;
600			m->m_len -= size;
601			if (m->m_len > 0)
602				break;	/* device can't take no more */
603
604			m = m_free(m);
605		}
606
607		/* Put remainder of mbuf chain (if any) back on queue */
608		if (m != NULL) {
609			IF_PREPEND(&sc->outq, m);
610			break;
611		}
612
613		/* Full packet has been sent */
614		NG_H4_LOCK(sc);
615		NG_H4_STAT_PCKTS_SENT(sc->stat);
616		NG_H4_UNLOCK(sc);
617	}
618
619	/*
620	 * Call output process whether or not there is any output. We are
621	 * being called in lieu of ttstart and must do what it would.
622	 */
623
624	tt_oproc(sc->tp);
625
626	/*
627	 * This timeout is needed for operation on a pseudo-tty, because the
628	 * pty code doesn't call pppstart after it has drained the t_outq.
629	 */
630
631	NG_H4_LOCK(sc);
632
633	if (!IFQ_IS_EMPTY(&sc->outq) && !callout_pending(&sc->timo))
634		ng_callout(&sc->timo, sc->node, NULL, 1,
635			ng_h4_process_timeout, NULL, 0);
636
637	NG_H4_UNLOCK(sc);
638
639	return (0);
640} /* ng_h4_start */
641
642/*****************************************************************************
643 *****************************************************************************
644 **			    Netgraph node methods
645 *****************************************************************************
646 *****************************************************************************/
647
648/*
649 * Initialize a new node of this type. We only allow nodes to be created as
650 * a result of setting the line discipline on a tty, so always return an error
651 * if not.
652 */
653
654static int
655ng_h4_constructor(node_p node)
656{
657	return (EOPNOTSUPP);
658} /* ng_h4_constructor */
659
660/*
661 * Add a new hook. There can only be one.
662 */
663
664static int
665ng_h4_newhook(node_p node, hook_p hook, const char *name)
666{
667	ng_h4_info_p	sc = (ng_h4_info_p) NG_NODE_PRIVATE(node);
668
669	if (strcmp(name, NG_H4_HOOK) != 0)
670		return (EINVAL);
671
672	NG_H4_LOCK(sc);
673
674	if (sc->hook != NULL) {
675		NG_H4_UNLOCK(sc);
676		return (EISCONN);
677	}
678	sc->hook = hook;
679
680	NG_H4_UNLOCK(sc);
681
682	return (0);
683} /* ng_h4_newhook */
684
685/*
686 * Connect hook. Just say yes.
687 */
688
689static int
690ng_h4_connect(hook_p hook)
691{
692	ng_h4_info_p	sc = (ng_h4_info_p) NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
693
694	if (hook != sc->hook)
695		panic("%s: hook != sc->hook\n", __func__);
696
697	NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
698	NG_HOOK_FORCE_QUEUE(hook);
699
700	return (0);
701} /* ng_h4_connect */
702
703/*
704 * Disconnect the hook
705 */
706
707static int
708ng_h4_disconnect(hook_p hook)
709{
710	ng_h4_info_p	sc = (ng_h4_info_p) NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
711
712	/*
713	 * We need to check for sc != NULL because we can be called from
714	 * ng_h4_close() via ng_rmnode_self()
715	 */
716
717	if (sc != NULL) {
718		if (hook != sc->hook)
719			panic("%s: hook != sc->hook\n", __func__);
720
721		NG_H4_LOCK(sc);
722
723		/* XXX do we have to untimeout and drain out queue? */
724		if (callout_pending(&sc->timo))
725			ng_uncallout(&sc->timo, sc->node);
726
727		_IF_DRAIN(&sc->outq);
728
729		sc->state = NG_H4_W4_PKT_IND;
730		sc->want = 1;
731		sc->got = 0;
732
733		sc->hook = NULL;
734
735		NG_H4_UNLOCK(sc);
736	}
737
738	return (0);
739} /* ng_h4_disconnect */
740
741/*
742 * Remove this node. The does the netgraph portion of the shutdown.
743 * This should only be called indirectly from ng_h4_close().
744 */
745
746static int
747ng_h4_shutdown(node_p node)
748{
749	ng_h4_info_p	sc = (ng_h4_info_p) NG_NODE_PRIVATE(node);
750
751	NG_H4_LOCK(sc);
752
753	if (!sc->dying) {
754		NG_H4_UNLOCK(sc);
755
756		NG_NODE_REVIVE(node);	/* we will persist */
757
758		return (EOPNOTSUPP);
759	}
760
761	NG_H4_UNLOCK(sc);
762
763	NG_NODE_SET_PRIVATE(node, NULL);
764
765	_IF_DRAIN(&sc->outq);
766
767	NG_NODE_UNREF(node);
768	mtx_destroy(&sc->outq.ifq_mtx);
769	bzero(sc, sizeof(*sc));
770	free(sc, M_NETGRAPH_H4);
771
772	return (0);
773} /* ng_h4_shutdown */
774
775/*
776 * Receive incoming data from Netgraph system. Put it on our
777 * output queue and start output if necessary.
778 */
779
780static int
781ng_h4_rcvdata(hook_p hook, item_p item)
782{
783	ng_h4_info_p	 sc = (ng_h4_info_p)NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
784	struct mbuf	*m = NULL;
785	int		 qlen;
786
787	if (sc == NULL)
788		return (EHOSTDOWN);
789
790	if (hook != sc->hook)
791		panic("%s: hook != sc->hook\n", __func__);
792
793	NGI_GET_M(item, m);
794	NG_FREE_ITEM(item);
795
796	NG_H4_LOCK(sc);
797
798	if (_IF_QFULL(&sc->outq)) {
799		NG_H4_ERR("%s: %s - dropping mbuf, len=%d\n", __func__,
800			NG_NODE_NAME(sc->node), m->m_pkthdr.len);
801
802		NG_H4_STAT_OERROR(sc->stat);
803
804		NG_H4_UNLOCK(sc);
805
806		NG_FREE_M(m);
807
808		return (ENOBUFS);
809	}
810
811	NG_H4_INFO("%s: %s - queue mbuf, len=%d\n", __func__,
812		NG_NODE_NAME(sc->node), m->m_pkthdr.len);
813
814	_IF_ENQUEUE(&sc->outq, m);
815	qlen = _IF_QLEN(&sc->outq);
816
817	NG_H4_UNLOCK(sc);
818
819	/*
820	 * If qlen > 1, then we should already have a scheduled callout
821	 */
822
823	if (qlen == 1) {
824		mtx_lock(&Giant);
825		ng_h4_start(sc->tp);
826		mtx_unlock(&Giant);
827	}
828
829	return (0);
830} /* ng_h4_rcvdata */
831
832/*
833 * Receive control message
834 */
835
836static int
837ng_h4_rcvmsg(node_p node, item_p item, hook_p lasthook)
838{
839	ng_h4_info_p	 sc = (ng_h4_info_p) NG_NODE_PRIVATE(node);
840	struct ng_mesg	*msg = NULL, *resp = NULL;
841	int		 error = 0;
842
843	if (sc == NULL)
844		return (EHOSTDOWN);
845
846	NGI_GET_MSG(item, msg);
847	NG_H4_LOCK(sc);
848
849	switch (msg->header.typecookie) {
850	case NGM_GENERIC_COOKIE:
851		switch (msg->header.cmd) {
852		case NGM_TEXT_STATUS:
853			NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
854			if (resp == NULL)
855				error = ENOMEM;
856			else
857				snprintf(resp->data, NG_TEXTRESPONSE,
858					"Hook: %s\n"   \
859					"Debug: %d\n"  \
860					"State: %d\n"  \
861					"Queue: [have:%d,max:%d]\n" \
862					"Input: [got:%d,want:%d]",
863					(sc->hook != NULL)? NG_H4_HOOK : "",
864					sc->debug,
865					sc->state,
866					_IF_QLEN(&sc->outq),
867					sc->outq.ifq_maxlen,
868					sc->got,
869					sc->want);
870			break;
871
872		default:
873			error = EINVAL;
874			break;
875		}
876		break;
877
878	case NGM_H4_COOKIE:
879		switch (msg->header.cmd) {
880		case NGM_H4_NODE_RESET:
881			_IF_DRAIN(&sc->outq);
882			sc->state = NG_H4_W4_PKT_IND;
883			sc->want = 1;
884			sc->got = 0;
885			break;
886
887		case NGM_H4_NODE_GET_STATE:
888			NG_MKRESPONSE(resp, msg, sizeof(ng_h4_node_state_ep),
889				M_NOWAIT);
890			if (resp == NULL)
891				error = ENOMEM;
892			else
893				*((ng_h4_node_state_ep *)(resp->data)) =
894					sc->state;
895			break;
896
897		case NGM_H4_NODE_GET_DEBUG:
898			NG_MKRESPONSE(resp, msg, sizeof(ng_h4_node_debug_ep),
899				M_NOWAIT);
900			if (resp == NULL)
901				error = ENOMEM;
902			else
903				*((ng_h4_node_debug_ep *)(resp->data)) =
904					sc->debug;
905			break;
906
907		case NGM_H4_NODE_SET_DEBUG:
908			if (msg->header.arglen != sizeof(ng_h4_node_debug_ep))
909				error = EMSGSIZE;
910			else
911				sc->debug =
912					*((ng_h4_node_debug_ep *)(msg->data));
913			break;
914
915		case NGM_H4_NODE_GET_QLEN:
916			NG_MKRESPONSE(resp, msg, sizeof(ng_h4_node_qlen_ep),
917				M_NOWAIT);
918			if (resp == NULL)
919				error = ENOMEM;
920			else
921				*((ng_h4_node_qlen_ep *)(resp->data)) =
922					sc->outq.ifq_maxlen;
923			break;
924
925		case NGM_H4_NODE_SET_QLEN:
926			if (msg->header.arglen != sizeof(ng_h4_node_qlen_ep))
927				error = EMSGSIZE;
928			else if (*((ng_h4_node_qlen_ep *)(msg->data)) <= 0)
929				error = EINVAL;
930			else
931				IFQ_SET_MAXLEN(&sc->outq,
932					*((ng_h4_node_qlen_ep *)(msg->data)));
933			break;
934
935		case NGM_H4_NODE_GET_STAT:
936			NG_MKRESPONSE(resp, msg, sizeof(ng_h4_node_stat_ep),
937				M_NOWAIT);
938			if (resp == NULL)
939				error = ENOMEM;
940			else
941				bcopy(&sc->stat, resp->data,
942					sizeof(ng_h4_node_stat_ep));
943			break;
944
945		case NGM_H4_NODE_RESET_STAT:
946			NG_H4_STAT_RESET(sc->stat);
947			break;
948
949		default:
950			error = EINVAL;
951			break;
952		}
953		break;
954
955	default:
956		error = EINVAL;
957		break;
958	}
959
960	NG_H4_UNLOCK(sc);
961
962	NG_RESPOND_MSG(error, node, item, resp);
963	NG_FREE_MSG(msg);
964
965	return (error);
966} /* ng_h4_rcvmsg */
967
968/*
969 * Timeout processing function.
970 * We still have data to output to the device, so try sending more.
971 */
972
973static void
974ng_h4_process_timeout(node_p node, hook_p hook, void *arg1, int arg2)
975{
976	ng_h4_info_p	sc = (ng_h4_info_p) NG_NODE_PRIVATE(node);
977
978	mtx_lock(&Giant);
979	ng_h4_start(sc->tp);
980	mtx_unlock(&Giant);
981} /* ng_h4_process_timeout */
982
983/*
984 * Handle loading and unloading for this node type
985 */
986
987static int
988ng_h4_mod_event(module_t mod, int event, void *data)
989{
990	static int	ng_h4_ldisc;
991	int		error = 0;
992
993	switch (event) {
994	case MOD_LOAD:
995		/* Register line discipline */
996		mtx_lock(&Giant);
997		ng_h4_ldisc = ldisc_register(H4DISC, &ng_h4_disc);
998		mtx_unlock(&Giant);
999
1000		if (ng_h4_ldisc < 0) {
1001			printf("%s: can't register H4 line discipline\n",
1002				__func__);
1003			error = EIO;
1004		}
1005		break;
1006
1007	case MOD_UNLOAD:
1008		/* Unregister line discipline */
1009		mtx_lock(&Giant);
1010		ldisc_deregister(ng_h4_ldisc);
1011		mtx_unlock(&Giant);
1012		break;
1013
1014	default:
1015		error = EOPNOTSUPP;
1016		break;
1017	}
1018
1019	return (error);
1020} /* ng_h4_mod_event */
1021