1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2004 Ruslan Ermilov
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/param.h>
30#include <sys/errno.h>
31#include <sys/kernel.h>
32#include <sys/mbuf.h>
33#include <sys/systm.h>
34
35#include <netgraph/ng_message.h>
36#include <netgraph/ng_hub.h>
37#include <netgraph/netgraph.h>
38
39#ifdef NG_SEPARATE_MALLOC
40static MALLOC_DEFINE(M_NETGRAPH_HUB, "netgraph_hub", "netgraph hub node");
41#else
42#define M_NETGRAPH_HUB M_NETGRAPH
43#endif
44
45/* Per-node private data */
46struct ng_hub_private {
47	int		persistent;	/* can exist w/o hooks */
48};
49typedef struct ng_hub_private *priv_p;
50
51/* Netgraph node methods */
52static ng_constructor_t	ng_hub_constructor;
53static ng_rcvmsg_t	ng_hub_rcvmsg;
54static ng_shutdown_t	ng_hub_shutdown;
55static ng_rcvdata_t	ng_hub_rcvdata;
56static ng_disconnect_t	ng_hub_disconnect;
57
58/* List of commands and how to convert arguments to/from ASCII */
59static const struct ng_cmdlist ng_hub_cmdlist[] = {
60	{
61		NGM_HUB_COOKIE,
62		NGM_HUB_SET_PERSISTENT,
63		"setpersistent",
64		NULL,
65		NULL
66	},
67	{ 0 }
68};
69
70static struct ng_type ng_hub_typestruct = {
71	.version =	NG_ABI_VERSION,
72	.name =		NG_HUB_NODE_TYPE,
73	.constructor =	ng_hub_constructor,
74	.rcvmsg =	ng_hub_rcvmsg,
75	.shutdown =	ng_hub_shutdown,
76	.rcvdata =	ng_hub_rcvdata,
77	.disconnect =	ng_hub_disconnect,
78	.cmdlist =	ng_hub_cmdlist,
79};
80NETGRAPH_INIT(hub, &ng_hub_typestruct);
81
82static int
83ng_hub_constructor(node_p node)
84{
85	priv_p priv;
86
87	/* Allocate and initialize private info */
88	priv = malloc(sizeof(*priv), M_NETGRAPH_HUB, M_WAITOK | M_ZERO);
89
90	NG_NODE_SET_PRIVATE(node, priv);
91	return (0);
92}
93
94/*
95 * Receive a control message
96 */
97static int
98ng_hub_rcvmsg(node_p node, item_p item, hook_p lasthook)
99{
100	const priv_p priv = NG_NODE_PRIVATE(node);
101	int error = 0;
102	struct ng_mesg *msg;
103
104	NGI_GET_MSG(item, msg);
105	if (msg->header.typecookie == NGM_HUB_COOKIE &&
106	    msg->header.cmd == NGM_HUB_SET_PERSISTENT) {
107		priv->persistent = 1;
108	} else {
109		error = EINVAL;
110	}
111
112	NG_FREE_MSG(msg);
113	return (error);
114}
115
116static int
117ng_hub_rcvdata(hook_p hook, item_p item)
118{
119	const node_p node = NG_HOOK_NODE(hook);
120	int error = 0;
121	hook_p hook2;
122	struct mbuf * const m = NGI_M(item), *m2;
123	int nhooks;
124
125	if ((nhooks = NG_NODE_NUMHOOKS(node)) == 1) {
126		NG_FREE_ITEM(item);
127		return (0);
128	}
129	LIST_FOREACH(hook2, &node->nd_hooks, hk_hooks) {
130		if (hook2 == hook)
131			continue;
132		if (--nhooks == 1)
133			NG_FWD_ITEM_HOOK(error, item, hook2);
134		else {
135			if ((m2 = m_dup(m, M_NOWAIT)) == NULL) {
136				NG_FREE_ITEM(item);
137				return (ENOBUFS);
138			}
139			NG_SEND_DATA_ONLY(error, hook2, m2);
140			if (error)
141				continue;	/* don't give up */
142		}
143	}
144
145	return (error);
146}
147
148/*
149 * Shutdown node
150 */
151static int
152ng_hub_shutdown(node_p node)
153{
154	const priv_p priv = NG_NODE_PRIVATE(node);
155
156	free(priv, M_NETGRAPH_HUB);
157	NG_NODE_SET_PRIVATE(node, NULL);
158	NG_NODE_UNREF(node);
159	return (0);
160}
161
162static int
163ng_hub_disconnect(hook_p hook)
164{
165	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
166
167	if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0 &&
168	    NG_NODE_IS_VALID(NG_HOOK_NODE(hook)) && !priv->persistent)
169		ng_rmnode_self(NG_HOOK_NODE(hook));
170	return (0);
171}
172