/* * 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 * * $FreeBSD$ * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $ */ #include #include #include #include #include #include #include #include #include #include /* * 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 = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO); 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, M_NOWAIT); /* 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("%s", __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 */ free(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("%s", __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); }