1 2 /* 3 * ng_hole.c 4 * 5 * Copyright (c) 1996-1999 Whistle Communications, Inc. 6 * All rights reserved. 7 * 8 * Subject to the following obligations and disclaimer of warranty, use and 9 * redistribution of this software, in source or object code forms, with or 10 * without modifications are expressly permitted by Whistle Communications; 11 * provided, however, that: 12 * 1. Any and all reproductions of the source or object code must include the 13 * copyright notice above and the following disclaimer of warranties; and 14 * 2. No rights are granted, in any manner or form, to use Whistle 15 * Communications, Inc. trademarks, including the mark "WHISTLE 16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 17 * such appears in the above copyright notice or in the software. 18 * 19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 35 * OF SUCH DAMAGE. 36 * 37 * Author: Julian Elisher <julian@freebsd.org> 38 * 39 * $FreeBSD: src/sys/netgraph/ng_hole.c,v 1.4.2.1 2000/10/24 18:36:45 julian Exp $ 40 * $DragonFly: src/sys/netgraph/hole/ng_hole.c,v 1.3 2003/08/07 21:17:31 dillon Exp $ 41 * $Whistle: ng_hole.c,v 1.10 1999/11/01 09:24:51 julian Exp $ 42 */ 43 44 /* 45 * This node is a 'black hole' that simply discards everything it receives 46 */ 47 48 #include <sys/param.h> 49 #include <sys/kernel.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <netgraph/ng_message.h> 53 #include <netgraph/netgraph.h> 54 #include "ng_hole.h" 55 56 /* Netgraph methods */ 57 static ng_rcvdata_t ngh_rcvdata; 58 static ng_disconnect_t ngh_disconnect; 59 60 static struct ng_type typestruct = { 61 NG_VERSION, 62 NG_HOLE_NODE_TYPE, 63 NULL, 64 NULL, 65 NULL, 66 NULL, 67 NULL, 68 NULL, 69 NULL, 70 ngh_rcvdata, 71 ngh_rcvdata, 72 ngh_disconnect, 73 NULL 74 }; 75 NETGRAPH_INIT(hole, &typestruct); 76 77 /* 78 * Receive data 79 */ 80 static int 81 ngh_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 82 { 83 NG_FREE_DATA(m, meta); 84 return 0; 85 } 86 87 /* 88 * Hook disconnection 89 */ 90 static int 91 ngh_disconnect(hook_p hook) 92 { 93 if (hook->node->numhooks == 0) 94 ng_rmnode(hook->node); 95 return (0); 96 } 97