ng_UI.c revision 131112
152419Sjulian 252419Sjulian/* 352419Sjulian * ng_UI.c 452419Sjulian * 552419Sjulian * Copyright (c) 1996-1999 Whistle Communications, Inc. 652419Sjulian * All rights reserved. 752419Sjulian * 852419Sjulian * Subject to the following obligations and disclaimer of warranty, use and 952419Sjulian * redistribution of this software, in source or object code forms, with or 1052419Sjulian * without modifications are expressly permitted by Whistle Communications; 1152419Sjulian * provided, however, that: 1252419Sjulian * 1. Any and all reproductions of the source or object code must include the 1352419Sjulian * copyright notice above and the following disclaimer of warranties; and 1452419Sjulian * 2. No rights are granted, in any manner or form, to use Whistle 1552419Sjulian * Communications, Inc. trademarks, including the mark "WHISTLE 1652419Sjulian * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 1752419Sjulian * such appears in the above copyright notice or in the software. 1852419Sjulian * 1952419Sjulian * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 2052419Sjulian * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 2152419Sjulian * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 2252419Sjulian * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 2352419Sjulian * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 2452419Sjulian * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 2552419Sjulian * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 2652419Sjulian * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 2752419Sjulian * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 2852419Sjulian * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 2952419Sjulian * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 3052419Sjulian * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 3152419Sjulian * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 3252419Sjulian * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3352419Sjulian * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3452419Sjulian * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 3552419Sjulian * OF SUCH DAMAGE. 3652419Sjulian * 3767506Sjulian * Author: Julian Elischer <julian@freebsd.org> 3852419Sjulian * 3952419Sjulian * $FreeBSD: head/sys/netgraph/ng_UI.c 131112 2004-06-25 21:11:14Z julian $ 4052752Sjulian * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $ 4152419Sjulian */ 4252419Sjulian 4352419Sjulian#include <sys/param.h> 4452419Sjulian#include <sys/systm.h> 4552419Sjulian#include <sys/errno.h> 4652419Sjulian#include <sys/kernel.h> 4752419Sjulian#include <sys/malloc.h> 4852419Sjulian#include <sys/mbuf.h> 4952419Sjulian#include <sys/errno.h> 5052419Sjulian 5152419Sjulian 5252419Sjulian#include <netgraph/ng_message.h> 5352419Sjulian#include <netgraph/netgraph.h> 5452419Sjulian#include <netgraph/ng_UI.h> 5552419Sjulian 5652419Sjulian/* 5752419Sjulian * DEFINITIONS 5852419Sjulian */ 5952419Sjulian 6052419Sjulian/* Everything, starting with sdlc on has defined UI as 0x03 */ 6152419Sjulian#define HDLC_UI 0x03 6252419Sjulian 6352419Sjulian/* Node private data */ 6453393Sarchiestruct ng_UI_private { 6552419Sjulian hook_p downlink; 6652419Sjulian hook_p uplink; 6752419Sjulian}; 6853393Sarchietypedef struct ng_UI_private *priv_p; 6952419Sjulian 7052419Sjulian/* Netgraph node methods */ 7152752Sjulianstatic ng_constructor_t ng_UI_constructor; 7252752Sjulianstatic ng_rcvmsg_t ng_UI_rcvmsg; 7370700Sjulianstatic ng_shutdown_t ng_UI_shutdown; 7452752Sjulianstatic ng_newhook_t ng_UI_newhook; 7552752Sjulianstatic ng_rcvdata_t ng_UI_rcvdata; 7652752Sjulianstatic ng_disconnect_t ng_UI_disconnect; 7752419Sjulian 7852419Sjulian/* Node type descriptor */ 7952419Sjulianstatic struct ng_type typestruct = { 80129823Sjulian .version = NG_ABI_VERSION, 81129823Sjulian .name = NG_UI_NODE_TYPE, 82129823Sjulian .constructor = ng_UI_constructor, 83129823Sjulian .rcvmsg = ng_UI_rcvmsg, 84129823Sjulian .shutdown = ng_UI_shutdown, 85129823Sjulian .newhook = ng_UI_newhook, 86129823Sjulian .rcvdata = ng_UI_rcvdata, 87129823Sjulian .disconnect = ng_UI_disconnect, 8852419Sjulian}; 8952419SjulianNETGRAPH_INIT(UI, &typestruct); 9052419Sjulian 9152419Sjulian/************************************************************************ 9252419Sjulian NETGRAPH NODE STUFF 9352419Sjulian ************************************************************************/ 9452419Sjulian 9552419Sjulian/* 9652419Sjulian * Create a newborn node. We start with an implicit reference. 9752419Sjulian */ 9852419Sjulian 9952419Sjulianstatic int 10070784Sjulianng_UI_constructor(node_p node) 10152419Sjulian{ 10252419Sjulian priv_p priv; 10352419Sjulian 10452419Sjulian /* Allocate private structure */ 10568876Sdwmalone MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 10670700Sjulian if (priv == NULL) { 10752419Sjulian return (ENOMEM); 10852419Sjulian } 10970784Sjulian NG_NODE_SET_PRIVATE(node, priv); 11052419Sjulian return (0); 11152419Sjulian} 11252419Sjulian 11352419Sjulian/* 11452419Sjulian * Give our ok for a hook to be added 11552419Sjulian */ 11652419Sjulianstatic int 11752419Sjulianng_UI_newhook(node_p node, hook_p hook, const char *name) 11852419Sjulian{ 11970784Sjulian const priv_p priv = NG_NODE_PRIVATE(node); 12052419Sjulian 12152419Sjulian if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) { 12252419Sjulian if (priv->downlink) 12352419Sjulian return (EISCONN); 12452419Sjulian priv->downlink = hook; 12552419Sjulian } else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) { 12652419Sjulian if (priv->uplink) 12752419Sjulian return (EISCONN); 12852419Sjulian priv->uplink = hook; 12952419Sjulian } else 13052419Sjulian return (EINVAL); 13152419Sjulian return (0); 13252419Sjulian} 13352419Sjulian 13452419Sjulian/* 13552419Sjulian * Receive a control message 13652419Sjulian */ 13752419Sjulianstatic int 13870700Sjulianng_UI_rcvmsg(node_p node, item_p item, hook_p lasthook) 13952419Sjulian{ 14070700Sjulian int error; 14170784Sjulian const priv_p priv = NG_NODE_PRIVATE(node); 14270700Sjulian struct ng_mesg *msg; 14369922Sjulian 14470700Sjulian msg = NGI_MSG(item); /* only peeking */ 14569922Sjulian if ((msg->header.typecookie == NGM_FLOW_COOKIE) && lasthook) { 14669922Sjulian if (lasthook == priv->downlink) { 14769922Sjulian if (priv->uplink) { 14870784Sjulian NG_FWD_ITEM_HOOK(error, item, priv->uplink); 14970700Sjulian return (error); 15069922Sjulian } 15169922Sjulian } else { 15269922Sjulian if (priv->downlink) { 15370784Sjulian NG_FWD_ITEM_HOOK(error, item, priv->downlink); 15470700Sjulian return (error); 15569922Sjulian } 15669922Sjulian } 15769922Sjulian } 15869922Sjulian 15970784Sjulian NG_FREE_ITEM(item); 16052419Sjulian return (EINVAL); 16152419Sjulian} 16252419Sjulian 16352419Sjulian#define MAX_ENCAPS_HDR 1 16452419Sjulian#define ERROUT(x) do { error = (x); goto done; } while (0) 16552419Sjulian 16652419Sjulian/* 16752419Sjulian * Receive a data frame 16852419Sjulian */ 16952419Sjulianstatic int 17070700Sjulianng_UI_rcvdata(hook_p hook, item_p item) 17152419Sjulian{ 17270784Sjulian const node_p node = NG_HOOK_NODE(hook); 17370784Sjulian const priv_p priv = NG_NODE_PRIVATE(node); 17470700Sjulian struct mbuf *m; 17552419Sjulian int error = 0; 17652419Sjulian 17770700Sjulian NGI_GET_M(item, m); 17852419Sjulian if (hook == priv->downlink) { 17952419Sjulian u_char *start, *ptr; 18052419Sjulian 181131112Sjulian if (m->m_len < MAX_ENCAPS_HDR 182131112Sjulian && !(m = m_pullup(m, MAX_ENCAPS_HDR))) 18352419Sjulian ERROUT(ENOBUFS); 18452419Sjulian ptr = start = mtod(m, u_char *); 18552419Sjulian 18652419Sjulian /* Must be UI frame */ 18752419Sjulian if (*ptr++ != HDLC_UI) 18852419Sjulian ERROUT(0); 18952419Sjulian 19052419Sjulian m_adj(m, ptr - start); 19170700Sjulian NG_FWD_NEW_DATA(error, item, priv->uplink, m); /* m -> NULL */ 19252419Sjulian } else if (hook == priv->uplink) { 193111119Simp M_PREPEND(m, 1, M_DONTWAIT); /* Prepend IP NLPID */ 19452419Sjulian if (!m) 19552419Sjulian ERROUT(ENOBUFS); 19652419Sjulian mtod(m, u_char *)[0] = HDLC_UI; 19770700Sjulian NG_FWD_NEW_DATA(error, item, priv->downlink, m); /* m -> NULL */ 19852419Sjulian } else 19987599Sobrien panic(__func__); 20052419Sjulian 20152419Sjuliandone: 20270700Sjulian NG_FREE_M(m); /* does nothing if m == NULL */ 20370700Sjulian if (item) 20470700Sjulian NG_FREE_ITEM(item); 20552419Sjulian return (error); 20652419Sjulian} 20752419Sjulian 20852419Sjulian/* 20952419Sjulian * Shutdown node 21052419Sjulian */ 21152419Sjulianstatic int 21270700Sjulianng_UI_shutdown(node_p node) 21352419Sjulian{ 21470784Sjulian const priv_p priv = NG_NODE_PRIVATE(node); 21552419Sjulian 21652419Sjulian /* Take down netgraph node */ 21752419Sjulian FREE(priv, M_NETGRAPH); 21870784Sjulian NG_NODE_SET_PRIVATE(node, NULL); 21970784Sjulian NG_NODE_UNREF(node); 22052419Sjulian return (0); 22152419Sjulian} 22252419Sjulian 22352419Sjulian/* 22452419Sjulian * Hook disconnection 22552419Sjulian */ 22652419Sjulianstatic int 22752419Sjulianng_UI_disconnect(hook_p hook) 22852419Sjulian{ 22970784Sjulian const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 23052419Sjulian 23170700Sjulian if (hook == priv->downlink) 23252419Sjulian priv->downlink = NULL; 23352419Sjulian else if (hook == priv->uplink) 23452419Sjulian priv->uplink = NULL; 23552419Sjulian else 23687599Sobrien panic(__func__); 23770700Sjulian /* 23870700Sjulian * If we are not already shutting down, 23970700Sjulian * and we have no more hooks, then DO shut down. 24070700Sjulian */ 24170784Sjulian if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 24270784Sjulian && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) { 24370784Sjulian ng_rmnode_self(NG_HOOK_NODE(hook)); 24470700Sjulian } 24552419Sjulian return (0); 24652419Sjulian} 24752419Sjulian 248