1 /* 2 * ng_echo.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Author: Julian Elisher <julian@freebsd.org> 39 * 40 * $FreeBSD$ 41 * $Whistle: ng_echo.c,v 1.13 1999/11/01 09:24:51 julian Exp $ 42 */ 43 44 /* 45 * Netgraph "echo" node 46 * 47 * This node simply bounces data and messages back to whence they came. 48 */ 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/kernel.h> 53 #include <sys/malloc.h> 54 #include <sys/mbuf.h> 55 #include <netgraph/ng_message.h> 56 #include <netgraph/netgraph.h> 57 #include <netgraph/ng_echo.h> 58 59 /* Netgraph methods */ 60 static ng_constructor_t nge_cons; 61 static ng_rcvmsg_t nge_rcvmsg; 62 static ng_rcvdata_t nge_rcvdata; 63 static ng_disconnect_t nge_disconnect; 64 65 /* Netgraph type */ 66 static struct ng_type typestruct = { 67 .version = NG_ABI_VERSION, 68 .name = NG_ECHO_NODE_TYPE, 69 .constructor = nge_cons, 70 .rcvmsg = nge_rcvmsg, 71 .rcvdata = nge_rcvdata, 72 .disconnect = nge_disconnect, 73 }; 74 NETGRAPH_INIT(echo, &typestruct); 75 76 static int 77 nge_cons(node_p node) 78 { 79 return (0); 80 } 81 82 /* 83 * Receive control message. We just bounce it back as a reply. 84 */ 85 static int 86 nge_rcvmsg(node_p node, item_p item, hook_p lasthook) 87 { 88 struct ng_mesg *msg; 89 int error = 0; 90 91 NGI_GET_MSG(item, msg); 92 msg->header.flags |= NGF_RESP; 93 NG_RESPOND_MSG(error, node, item, msg); 94 return (error); 95 } 96 97 /* 98 * Receive data 99 */ 100 static int 101 nge_rcvdata(hook_p hook, item_p item) 102 { 103 int error; 104 105 NG_FWD_ITEM_HOOK(error, item, hook); 106 return (error); 107 } 108 109 /* 110 * Removal of the last link destroys the nodeo 111 */ 112 static int 113 nge_disconnect(hook_p hook) 114 { 115 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 116 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) { 117 ng_rmnode_self(NG_HOOK_NODE(hook)); 118 } 119 return (0); 120 } 121