[dragonfly.git] / sys / netgraph7 / ng_UI.c

/*
 * ng_UI.c
 */

/*-
 * Copyright (c) 1996-1999 Whistle Communications, Inc.
 * All rights reserved.
 * 
 * Subject to the following obligations and disclaimer of warranty, use and
 * redistribution of this software, in source or object code forms, with or
 * without modifications are expressly permitted by Whistle Communications;
 * provided, however, that:
 * 1. Any and all reproductions of the source or object code must include the
 *    copyright notice above and the following disclaimer of warranties; and
 * 2. No rights are granted, in any manner or form, to use Whistle
 *    Communications, Inc. trademarks, including the mark "WHISTLE
 *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
 *    such appears in the above copyright notice or in the software.
 * 
 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * Author: Julian Elischer <julian@freebsd.org>
 *
 * $FreeBSD: src/sys/netgraph/ng_UI.c,v 1.20 2005/01/07 01:45:39 imp Exp $
 * $DragonFly: src/sys/netgraph7/ng_UI.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
 * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/errno.h>


#include "ng_message.h"
#include "netgraph.h"
#include "ng_UI.h"

/*
 * DEFINITIONS
 */

/* Everything, starting with sdlc on has defined UI as 0x03 */
#define HDLC_UI	0x03

/* Node private data */
struct ng_UI_private {
	hook_p  downlink;
	hook_p  uplink;
};
typedef struct ng_UI_private *priv_p;

/* Netgraph node methods */
static ng_constructor_t	ng_UI_constructor;
static ng_rcvmsg_t	ng_UI_rcvmsg;
static ng_shutdown_t	ng_UI_shutdown;
static ng_newhook_t	ng_UI_newhook;
static ng_rcvdata_t	ng_UI_rcvdata;
static ng_disconnect_t	ng_UI_disconnect;

/* Node type descriptor */
static struct ng_type typestruct = {
	.version =	NG_ABI_VERSION,
	.name =		NG_UI_NODE_TYPE,
	.constructor =	ng_UI_constructor,
	.rcvmsg =	ng_UI_rcvmsg,
	.shutdown =	ng_UI_shutdown,
	.newhook =	ng_UI_newhook,
	.rcvdata =	ng_UI_rcvdata,
	.disconnect =	ng_UI_disconnect,
};
NETGRAPH_INIT(UI, &typestruct);

/************************************************************************
			NETGRAPH NODE STUFF
 ************************************************************************/

/*
 * Create a newborn node. We start with an implicit reference.
 */

static int
ng_UI_constructor(node_p node)
{
	priv_p  priv;

	/* Allocate private structure */
	priv = kmalloc(sizeof(*priv), M_NETGRAPH,
		       M_WAITOK | M_NULLOK | M_ZERO);
	if (priv == NULL) {
		return (ENOMEM);
	}
	NG_NODE_SET_PRIVATE(node, priv);
	return (0);
}

/*
 * Give our ok for a hook to be added
 */
static int
ng_UI_newhook(node_p node, hook_p hook, const char *name)
{
	const priv_p priv = NG_NODE_PRIVATE(node);

	if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) {
		if (priv->downlink)
			return (EISCONN);
		priv->downlink = hook;
	} else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) {
		if (priv->uplink)
			return (EISCONN);
		priv->uplink = hook;
	} else
		return (EINVAL);
	return (0);
}

/*
 * Receive a control message
 */
static int
ng_UI_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
	int	error;
	const priv_p priv = NG_NODE_PRIVATE(node);
	struct ng_mesg *msg;

	msg = NGI_MSG(item); /* only peeking */
	if ((msg->header.typecookie == NGM_FLOW_COOKIE) && lasthook)  {
		if (lasthook == priv->downlink) {
			if (priv->uplink) {
				NG_FWD_ITEM_HOOK(error, item, priv->uplink);
				return (error);
			}
		} else {
			if (priv->downlink) {
				NG_FWD_ITEM_HOOK(error, item, priv->downlink);
				return (error);
			}
		}
	}
		
	NG_FREE_ITEM(item);
	return (EINVAL);
}

#define MAX_ENCAPS_HDR	1
#define ERROUT(x)	do { error = (x); goto done; } while (0)

/*
 * Receive a data frame
 */
static int
ng_UI_rcvdata(hook_p hook, item_p item)
{
	const node_p node = NG_HOOK_NODE(hook);
	const priv_p priv = NG_NODE_PRIVATE(node);
	struct mbuf *m;
	int error = 0;

	NGI_GET_M(item, m);
	if (hook == priv->downlink) {
		u_char *start, *ptr;

		if (m->m_len < MAX_ENCAPS_HDR
		    && !(m = m_pullup(m, MAX_ENCAPS_HDR)))
			ERROUT(ENOBUFS);
		ptr = start = mtod(m, u_char *);

		/* Must be UI frame */
		if (*ptr++ != HDLC_UI)
			ERROUT(0);

		m_adj(m, ptr - start);
		NG_FWD_NEW_DATA(error, item, priv->uplink, m);	/* m -> NULL */
	} else if (hook == priv->uplink) {
		M_PREPEND(m, 1, MB_DONTWAIT);	/* Prepend IP NLPID */
		if (!m)
			ERROUT(ENOBUFS);
		mtod(m, u_char *)[0] = HDLC_UI;
		NG_FWD_NEW_DATA(error, item, priv->downlink, m);	/* m -> NULL */
	} else
		panic(__func__);

done:
	NG_FREE_M(m);	/* does nothing if m == NULL */
	if (item)
		NG_FREE_ITEM(item);
	return (error);
}

/*
 * Shutdown node
 */
static int
ng_UI_shutdown(node_p node)
{
	const priv_p priv = NG_NODE_PRIVATE(node);

	/* Take down netgraph node */
	kfree(priv, M_NETGRAPH);
	NG_NODE_SET_PRIVATE(node, NULL);
	NG_NODE_UNREF(node);
	return (0);
}

/*
 * Hook disconnection
 */
static int
ng_UI_disconnect(hook_p hook)
{
	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));

	if (hook == priv->downlink)
		priv->downlink = NULL;
	else if (hook == priv->uplink)
		priv->uplink = NULL;
	else
		panic(__func__);
	/*
	 * If we are not already shutting down,
	 * and we have no more hooks, then DO shut down.
	 */
	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
			ng_rmnode_self(NG_HOOK_NODE(hook));
	}
	return (0);
}
Commit	Line	Data
b06ebda0 MD	1	/*
	2	* ng_UI.c
	3	*/
	4
	5	/*-
	6	* Copyright (c) 1996-1999 Whistle Communications, Inc.
	7	* All rights reserved.
	8	*
	9	* Subject to the following obligations and disclaimer of warranty, use and
	10	* redistribution of this software, in source or object code forms, with or
	11	* without modifications are expressly permitted by Whistle Communications;
	12	* provided, however, that:
	13	* 1. Any and all reproductions of the source or object code must include the
	14	* copyright notice above and the following disclaimer of warranties; and
	15	* 2. No rights are granted, in any manner or form, to use Whistle
	16	* Communications, Inc. trademarks, including the mark "WHISTLE
	17	* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
	18	* such appears in the above copyright notice or in the software.
	19	*
	20	* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
	21	* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
	22	* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
	23	* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
	24	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
	25	* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
	26	* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
	27	* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
	28	* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
	29	* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
	30	* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
	31	* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
	32	* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
	33	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	34	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	35	* THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
	36	* OF SUCH DAMAGE.
	37	*
	38	* Author: Julian Elischer <julian@freebsd.org>
	39	*
	40	* $FreeBSD: src/sys/netgraph/ng_UI.c,v 1.20 2005/01/07 01:45:39 imp Exp $
5a975a3d	41	* $DragonFly: src/sys/netgraph7/ng_UI.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
b06ebda0 MD	42	* $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $
	43	*/
	44
	45	#include <sys/param.h>
	46	#include <sys/systm.h>
	47	#include <sys/errno.h>
	48	#include <sys/kernel.h>
	49	#include <sys/malloc.h>
	50	#include <sys/mbuf.h>
	51	#include <sys/errno.h>
	52
	53
5a975a3d MD	54	#include "ng_message.h"
	55	#include "netgraph.h"
	56	#include "ng_UI.h"
b06ebda0 MD	57
	58	/*
	59	* DEFINITIONS
	60	*/
	61
	62	/* Everything, starting with sdlc on has defined UI as 0x03 */
	63	#define HDLC_UI 0x03
	64
	65	/* Node private data */
	66	struct ng_UI_private {
	67	hook_p downlink;
	68	hook_p uplink;
	69	};
	70	typedef struct ng_UI_private *priv_p;
	71
	72	/* Netgraph node methods */
	73	static ng_constructor_t ng_UI_constructor;
	74	static ng_rcvmsg_t ng_UI_rcvmsg;
	75	static ng_shutdown_t ng_UI_shutdown;
	76	static ng_newhook_t ng_UI_newhook;
	77	static ng_rcvdata_t ng_UI_rcvdata;
	78	static ng_disconnect_t ng_UI_disconnect;
	79
	80	/* Node type descriptor */
	81	static struct ng_type typestruct = {
	82	.version = NG_ABI_VERSION,
	83	.name = NG_UI_NODE_TYPE,
	84	.constructor = ng_UI_constructor,
	85	.rcvmsg = ng_UI_rcvmsg,
	86	.shutdown = ng_UI_shutdown,
	87	.newhook = ng_UI_newhook,
	88	.rcvdata = ng_UI_rcvdata,
	89	.disconnect = ng_UI_disconnect,
	90	};
	91	NETGRAPH_INIT(UI, &typestruct);
	92
	93	/************************************************************************
	94	NETGRAPH NODE STUFF
	95	************************************************************************/
	96
	97	/*
	98	* Create a newborn node. We start with an implicit reference.
	99	*/
	100
	101	static int
	102	ng_UI_constructor(node_p node)
	103	{
	104	priv_p priv;
	105
	106	/* Allocate private structure */
fc025606 SW	107	priv = kmalloc(sizeof(*priv), M_NETGRAPH,
fc025606 SW	108	M_WAITOK \| M_NULLOK \| M_ZERO);
b06ebda0 MD	109	if (priv == NULL) {
	110	return (ENOMEM);
	111	}
	112	NG_NODE_SET_PRIVATE(node, priv);
	113	return (0);
	114	}
	115
	116	/*
	117	* Give our ok for a hook to be added
	118	*/
	119	static int
	120	ng_UI_newhook(node_p node, hook_p hook, const char *name)
	121	{
	122	const priv_p priv = NG_NODE_PRIVATE(node);
	123
	124	if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) {
	125	if (priv->downlink)
	126	return (EISCONN);
	127	priv->downlink = hook;
	128	} else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) {
	129	if (priv->uplink)
	130	return (EISCONN);
	131	priv->uplink = hook;
	132	} else
	133	return (EINVAL);
	134	return (0);
	135	}
	136
	137	/*
	138	* Receive a control message
	139	*/
	140	static int
	141	ng_UI_rcvmsg(node_p node, item_p item, hook_p lasthook)
	142	{
	143	int error;
	144	const priv_p priv = NG_NODE_PRIVATE(node);
	145	struct ng_mesg *msg;
	146
	147	msg = NGI_MSG(item); /* only peeking */
	148	if ((msg->header.typecookie == NGM_FLOW_COOKIE) && lasthook) {
	149	if (lasthook == priv->downlink) {
	150	if (priv->uplink) {
	151	NG_FWD_ITEM_HOOK(error, item, priv->uplink);
	152	return (error);
	153	}
	154	} else {
	155	if (priv->downlink) {
	156	NG_FWD_ITEM_HOOK(error, item, priv->downlink);
	157	return (error);
	158	}
	159	}
	160	}
	161
	162	NG_FREE_ITEM(item);
	163	return (EINVAL);
	164	}
	165
	166	#define MAX_ENCAPS_HDR 1
	167	#define ERROUT(x) do { error = (x); goto done; } while (0)
	168
	169	/*
	170	* Receive a data frame
	171	*/
	172	static int
173	ng_UI_rcvdata(hook_p hook, item_p item)
174	{
175	const node_p node = NG_HOOK_NODE(hook);
176	const priv_p priv = NG_NODE_PRIVATE(node);
177	struct mbuf *m;
178	int error = 0;
179
180	NGI_GET_M(item, m);
181	if (hook == priv->downlink) {
182	u_char start, ptr;
183
184	if (m->m_len < MAX_ENCAPS_HDR
185	&& !(m = m_pullup(m, MAX_ENCAPS_HDR)))
186	ERROUT(ENOBUFS);
187	ptr = start = mtod(m, u_char *);
188
189	/* Must be UI frame */
190	if (*ptr++ != HDLC_UI)
191	ERROUT(0);
192
193	m_adj(m, ptr - start);
194	NG_FWD_NEW_DATA(error, item, priv->uplink, m); /* m -> NULL */
195	} else if (hook == priv->uplink) {
5a975a3d	196	M_PREPEND(m, 1, MB_DONTWAIT); /* Prepend IP NLPID */
b06ebda0 MD	197	if (!m)
	198	ERROUT(ENOBUFS);
	199	mtod(m, u_char *)[0] = HDLC_UI;
	200	NG_FWD_NEW_DATA(error, item, priv->downlink, m); /* m -> NULL */
	201	} else
	202	panic(__func__);
	203
	204	done:
	205	NG_FREE_M(m); /* does nothing if m == NULL */
	206	if (item)
	207	NG_FREE_ITEM(item);
	208	return (error);
	209	}
	210
	211	/*
	212	* Shutdown node
	213	*/
	214	static int
	215	ng_UI_shutdown(node_p node)
	216	{
	217	const priv_p priv = NG_NODE_PRIVATE(node);
	218
	219	/* Take down netgraph node */
fc025606	220	kfree(priv, M_NETGRAPH);
b06ebda0 MD	221	NG_NODE_SET_PRIVATE(node, NULL);
	222	NG_NODE_UNREF(node);
	223	return (0);
	224	}
	225
	226	/*
	227	* Hook disconnection
	228	*/
	229	static int
	230	ng_UI_disconnect(hook_p hook)
	231	{
	232	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
	233
	234	if (hook == priv->downlink)
	235	priv->downlink = NULL;
	236	else if (hook == priv->uplink)
	237	priv->uplink = NULL;
	238	else
	239	panic(__func__);
	240	/*
	241	* If we are not already shutting down,
	242	* and we have no more hooks, then DO shut down.
	243	*/
	244	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
	245	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
	246	ng_rmnode_self(NG_HOOK_NODE(hook));
	247	}
	248	return (0);
	249	}
	250