ng_UI.c revision 139823
1243730Srwatson/* 2243730Srwatson * ng_UI.c 3243730Srwatson */ 4243730Srwatson 5243730Srwatson/*- 6243730Srwatson * Copyright (c) 1996-1999 Whistle Communications, Inc. 7243730Srwatson * All rights reserved. 8243730Srwatson * 9243730Srwatson * Subject to the following obligations and disclaimer of warranty, use and 10243730Srwatson * redistribution of this software, in source or object code forms, with or 11243730Srwatson * without modifications are expressly permitted by Whistle Communications; 12243730Srwatson * provided, however, that: 13243730Srwatson * 1. Any and all reproductions of the source or object code must include the 14243730Srwatson * copyright notice above and the following disclaimer of warranties; and 15243730Srwatson * 2. No rights are granted, in any manner or form, to use Whistle 16243730Srwatson * Communications, Inc. trademarks, including the mark "WHISTLE 17243730Srwatson * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18243730Srwatson * such appears in the above copyright notice or in the software. 19243730Srwatson * 20243730Srwatson * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21243730Srwatson * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22243730Srwatson * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23243730Srwatson * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24243730Srwatson * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25243730Srwatson * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26243730Srwatson * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27243730Srwatson * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28243730Srwatson * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29243730Srwatson * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30243730Srwatson * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31243730Srwatson * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32243730Srwatson * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33243730Srwatson * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34243730Srwatson * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35243730Srwatson * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36243730Srwatson * OF SUCH DAMAGE. 37243730Srwatson * 38243730Srwatson * Author: Julian Elischer <julian@freebsd.org> 39243730Srwatson * 40243730Srwatson * $FreeBSD: head/sys/netgraph/ng_UI.c 139823 2005-01-07 01:45:51Z imp $ 41243730Srwatson * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $ 42243730Srwatson */ 43243730Srwatson 44243730Srwatson#include <sys/param.h> 45243730Srwatson#include <sys/systm.h> 46243730Srwatson#include <sys/errno.h> 47243730Srwatson#include <sys/kernel.h> 48243730Srwatson#include <sys/malloc.h> 49243730Srwatson#include <sys/mbuf.h> 50243730Srwatson#include <sys/errno.h> 51243730Srwatson 52243730Srwatson 53243730Srwatson#include <netgraph/ng_message.h> 54243730Srwatson#include <netgraph/netgraph.h> 55243730Srwatson#include <netgraph/ng_UI.h> 56243730Srwatson 57243730Srwatson/* 58243730Srwatson * DEFINITIONS 59243730Srwatson */ 60243730Srwatson 61243730Srwatson/* Everything, starting with sdlc on has defined UI as 0x03 */ 62243730Srwatson#define HDLC_UI 0x03 63243730Srwatson 64243730Srwatson/* Node private data */ 65243730Srwatsonstruct ng_UI_private { 66243730Srwatson hook_p downlink; 67243730Srwatson hook_p uplink; 68243730Srwatson}; 69243730Srwatsontypedef struct ng_UI_private *priv_p; 70243730Srwatson 71243730Srwatson/* Netgraph node methods */ 72243730Srwatsonstatic ng_constructor_t ng_UI_constructor; 73243730Srwatsonstatic ng_rcvmsg_t ng_UI_rcvmsg; 74243730Srwatsonstatic ng_shutdown_t ng_UI_shutdown; 75243730Srwatsonstatic ng_newhook_t ng_UI_newhook; 76243730Srwatsonstatic ng_rcvdata_t ng_UI_rcvdata; 77243730Srwatsonstatic ng_disconnect_t ng_UI_disconnect; 78243730Srwatson 79243730Srwatson/* Node type descriptor */ 80243730Srwatsonstatic struct ng_type typestruct = { 81243730Srwatson .version = NG_ABI_VERSION, 82243730Srwatson .name = NG_UI_NODE_TYPE, 83243730Srwatson .constructor = ng_UI_constructor, 84243730Srwatson .rcvmsg = ng_UI_rcvmsg, 85243730Srwatson .shutdown = ng_UI_shutdown, 86243730Srwatson .newhook = ng_UI_newhook, 87243730Srwatson .rcvdata = ng_UI_rcvdata, 88243730Srwatson .disconnect = ng_UI_disconnect, 89243730Srwatson}; 90243730SrwatsonNETGRAPH_INIT(UI, &typestruct); 91243730Srwatson 92243730Srwatson/************************************************************************ 93243730Srwatson NETGRAPH NODE STUFF 94243730Srwatson ************************************************************************/ 95243730Srwatson 96243730Srwatson/* 97243730Srwatson * Create a newborn node. We start with an implicit reference. 98243730Srwatson */ 99243730Srwatson 100243730Srwatsonstatic int 101243730Srwatsonng_UI_constructor(node_p node) 102243730Srwatson{ 103243730Srwatson priv_p priv; 104243730Srwatson 105243730Srwatson /* Allocate private structure */ 106243730Srwatson MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 107243730Srwatson if (priv == NULL) { 108243730Srwatson return (ENOMEM); 109243730Srwatson } 110243730Srwatson NG_NODE_SET_PRIVATE(node, priv); 111243730Srwatson return (0); 112243730Srwatson} 113243730Srwatson 114243730Srwatson/* 115243730Srwatson * Give our ok for a hook to be added 116243730Srwatson */ 117243730Srwatsonstatic int 118243730Srwatsonng_UI_newhook(node_p node, hook_p hook, const char *name) 119243730Srwatson{ 120243730Srwatson const priv_p priv = NG_NODE_PRIVATE(node); 121243730Srwatson 122243730Srwatson if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) { 123243730Srwatson if (priv->downlink) 124243730Srwatson return (EISCONN); 125243730Srwatson priv->downlink = hook; 126243730Srwatson } else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) { 127243730Srwatson if (priv->uplink) 128243730Srwatson return (EISCONN); 129243730Srwatson priv->uplink = hook; 130243730Srwatson } else 131243730Srwatson return (EINVAL); 132243730Srwatson return (0); 133243730Srwatson} 134243730Srwatson 135243730Srwatson/* 136243730Srwatson * Receive a control message 137243730Srwatson */ 138243730Srwatsonstatic int 139243730Srwatsonng_UI_rcvmsg(node_p node, item_p item, hook_p lasthook) 140243730Srwatson{ 141243730Srwatson int error; 142243730Srwatson const priv_p priv = NG_NODE_PRIVATE(node); 143243730Srwatson struct ng_mesg *msg; 144243730Srwatson 145243730Srwatson msg = NGI_MSG(item); /* only peeking */ 146243730Srwatson if ((msg->header.typecookie == NGM_FLOW_COOKIE) && lasthook) { 147243730Srwatson if (lasthook == priv->downlink) { 148243730Srwatson if (priv->uplink) { 149243730Srwatson NG_FWD_ITEM_HOOK(error, item, priv->uplink); 150243730Srwatson return (error); 151243730Srwatson } 152243730Srwatson } else { 153243730Srwatson if (priv->downlink) { 154243730Srwatson NG_FWD_ITEM_HOOK(error, item, priv->downlink); 155243730Srwatson return (error); 156243730Srwatson } 157243730Srwatson } 158243730Srwatson } 159243730Srwatson 160243730Srwatson NG_FREE_ITEM(item); 161243730Srwatson return (EINVAL); 162243730Srwatson} 163243730Srwatson 164243730Srwatson#define MAX_ENCAPS_HDR 1 165243730Srwatson#define ERROUT(x) do { error = (x); goto done; } while (0) 166243730Srwatson 167243730Srwatson/* 168243730Srwatson * Receive a data frame 169243730Srwatson */ 170243730Srwatsonstatic int 171243730Srwatsonng_UI_rcvdata(hook_p hook, item_p item) 172243730Srwatson{ 173243730Srwatson const node_p node = NG_HOOK_NODE(hook); 174243730Srwatson const priv_p priv = NG_NODE_PRIVATE(node); 175243730Srwatson struct mbuf *m; 176243730Srwatson int error = 0; 177243730Srwatson 178243730Srwatson NGI_GET_M(item, m); 179243730Srwatson if (hook == priv->downlink) { 180243730Srwatson u_char *start, *ptr; 181243730Srwatson 182243730Srwatson if (m->m_len < MAX_ENCAPS_HDR 183243730Srwatson && !(m = m_pullup(m, MAX_ENCAPS_HDR))) 184243730Srwatson ERROUT(ENOBUFS); 185243730Srwatson ptr = start = mtod(m, u_char *); 186243730Srwatson 187243730Srwatson /* Must be UI frame */ 188243730Srwatson if (*ptr++ != HDLC_UI) 189243730Srwatson ERROUT(0); 190243730Srwatson 191243730Srwatson m_adj(m, ptr - start); 192243730Srwatson NG_FWD_NEW_DATA(error, item, priv->uplink, m); /* m -> NULL */ 193243730Srwatson } else if (hook == priv->uplink) { 194243730Srwatson M_PREPEND(m, 1, M_DONTWAIT); /* Prepend IP NLPID */ 195243730Srwatson if (!m) 196243730Srwatson ERROUT(ENOBUFS); 197243730Srwatson mtod(m, u_char *)[0] = HDLC_UI; 198243730Srwatson NG_FWD_NEW_DATA(error, item, priv->downlink, m); /* m -> NULL */ 199243730Srwatson } else 200243730Srwatson panic(__func__); 201243730Srwatson 202243730Srwatsondone: 203243730Srwatson NG_FREE_M(m); /* does nothing if m == NULL */ 204243730Srwatson if (item) 205243730Srwatson NG_FREE_ITEM(item); 206243730Srwatson return (error); 207243730Srwatson} 208243730Srwatson 209243730Srwatson/* 210243730Srwatson * Shutdown node 211243730Srwatson */ 212243730Srwatsonstatic int 213243730Srwatsonng_UI_shutdown(node_p node) 214243730Srwatson{ 215243730Srwatson const priv_p priv = NG_NODE_PRIVATE(node); 216243730Srwatson 217243730Srwatson /* Take down netgraph node */ 218243730Srwatson FREE(priv, M_NETGRAPH); 219243730Srwatson NG_NODE_SET_PRIVATE(node, NULL); 220243730Srwatson NG_NODE_UNREF(node); 221243730Srwatson return (0); 222243730Srwatson} 223243730Srwatson 224243730Srwatson/* 225243730Srwatson * Hook disconnection 226243730Srwatson */ 227243730Srwatsonstatic int 228243730Srwatsonng_UI_disconnect(hook_p hook) 229243730Srwatson{ 230243730Srwatson const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 231243730Srwatson 232243730Srwatson if (hook == priv->downlink) 233243730Srwatson priv->downlink = NULL; 234243730Srwatson else if (hook == priv->uplink) 235243730Srwatson priv->uplink = NULL; 236243730Srwatson else 237243730Srwatson panic(__func__); 238243730Srwatson /* 239243730Srwatson * If we are not already shutting down, 240243730Srwatson * and we have no more hooks, then DO shut down. 241243730Srwatson */ 242243730Srwatson if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 243243730Srwatson && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) { 244243730Srwatson ng_rmnode_self(NG_HOOK_NODE(hook)); 245243730Srwatson } 246243730Srwatson return (0); 247243730Srwatson} 248243730Srwatson 249243730Srwatson