1 /* 2 * ng_hole.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: src/sys/netgraph/ng_hole.c,v 1.15 2005/12/09 07:09:44 ru Exp $ 41 * $DragonFly: src/sys/netgraph7/ng_hole.c,v 1.2 2008/06/26 23:05:35 dillon Exp $ 42 * $Whistle: ng_hole.c,v 1.10 1999/11/01 09:24:51 julian Exp $ 43 */ 44 45 /* 46 * This node is a 'black hole' that simply discards everything it receives 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/kernel.h> 52 #include <sys/malloc.h> 53 #include <sys/mbuf.h> 54 #include <netgraph7/ng_message.h> 55 #include <netgraph7/netgraph.h> 56 #include <netgraph7/ng_parse.h> 57 #include "ng_hole.h" 58 59 /* Per hook private info. */ 60 struct ng_hole_hookinfo { 61 struct ng_hole_hookstat stats; 62 }; 63 typedef struct ng_hole_hookinfo *hinfo_p; 64 65 /* Parse type for struct ng_hole_hookstat. */ 66 static const struct ng_parse_struct_field ng_hole_hookstat_type_fields[] = 67 NG_HOLE_HOOKSTAT_TYPE_INFO; 68 static const struct ng_parse_type ng_hole_hookstat_type = { 69 &ng_parse_struct_type, 70 &ng_hole_hookstat_type_fields 71 }; 72 73 /* List of commands and how to convert arguments to/from ASCII. */ 74 static const struct ng_cmdlist ng_hole_cmdlist[] = { 75 { 76 NGM_HOLE_COOKIE, 77 NGM_HOLE_GET_STATS, 78 "getstats", 79 &ng_parse_hookbuf_type, 80 &ng_hole_hookstat_type 81 }, 82 { 83 NGM_HOLE_COOKIE, 84 NGM_HOLE_CLR_STATS, 85 "clrstats", 86 &ng_parse_hookbuf_type, 87 NULL 88 }, 89 { 90 NGM_HOLE_COOKIE, 91 NGM_HOLE_GETCLR_STATS, 92 "getclrstats", 93 &ng_parse_hookbuf_type, 94 &ng_hole_hookstat_type 95 }, 96 { 0 } 97 }; 98 99 /* Netgraph methods */ 100 static ng_constructor_t ngh_cons; 101 static ng_rcvmsg_t ngh_rcvmsg; 102 static ng_newhook_t ngh_newhook; 103 static ng_rcvdata_t ngh_rcvdata; 104 static ng_disconnect_t ngh_disconnect; 105 106 static struct ng_type typestruct = { 107 .version = NG_ABI_VERSION, 108 .name = NG_HOLE_NODE_TYPE, 109 .constructor = ngh_cons, 110 .rcvmsg = ngh_rcvmsg, 111 .newhook = ngh_newhook, 112 .rcvdata = ngh_rcvdata, 113 .disconnect = ngh_disconnect, 114 .cmdlist = ng_hole_cmdlist, 115 }; 116 NETGRAPH_INIT(hole, &typestruct); 117 118 /* 119 * Be obliging. but no work to do. 120 */ 121 static int 122 ngh_cons(node_p node) 123 { 124 return(0); 125 } 126 127 /* 128 * Add a hook. 129 */ 130 static int 131 ngh_newhook(node_p node, hook_p hook, const char *name) 132 { 133 hinfo_p hip; 134 135 /* Create hook private structure. */ 136 hip = kmalloc(sizeof(*hip), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO); 137 if (hip == NULL) 138 return (ENOMEM); 139 NG_HOOK_SET_PRIVATE(hook, hip); 140 return (0); 141 } 142 143 /* 144 * Receive a control message. 145 */ 146 static int 147 ngh_rcvmsg(node_p node, item_p item, hook_p lasthook) 148 { 149 struct ng_mesg *msg; 150 struct ng_mesg *resp = NULL; 151 int error = 0; 152 struct ng_hole_hookstat *stats; 153 hook_p hook; 154 155 NGI_GET_MSG(item, msg); 156 switch (msg->header.typecookie) { 157 case NGM_HOLE_COOKIE: 158 switch (msg->header.cmd) { 159 case NGM_HOLE_GET_STATS: 160 case NGM_HOLE_CLR_STATS: 161 case NGM_HOLE_GETCLR_STATS: 162 /* Sanity check. */ 163 if (msg->header.arglen != NG_HOOKSIZ) { 164 error = EINVAL; 165 break; 166 } 167 /* Find hook. */ 168 hook = ng_findhook(node, (char *)msg->data); 169 if (hook == NULL) { 170 error = ENOENT; 171 break; 172 } 173 stats = &((hinfo_p)NG_HOOK_PRIVATE(hook))->stats; 174 /* Build response (if desired). */ 175 if (msg->header.cmd != NGM_HOLE_CLR_STATS) { 176 NG_MKRESPONSE(resp, msg, sizeof(*stats), 177 M_WAITOK | M_NULLOK); 178 if (resp == NULL) { 179 error = ENOMEM; 180 break; 181 } 182 bcopy(stats, resp->data, sizeof(*stats)); 183 } 184 /* Clear stats (if desired). */ 185 if (msg->header.cmd != NGM_HOLE_GET_STATS) 186 bzero(stats, sizeof(*stats)); 187 break; 188 default: /* Unknown command. */ 189 error = EINVAL; 190 break; 191 } 192 break; 193 default: /* Unknown type cookie. */ 194 error = EINVAL; 195 break; 196 } 197 NG_RESPOND_MSG(error, node, item, resp); 198 NG_FREE_MSG(msg); 199 return (error); 200 } 201 202 /* 203 * Receive data 204 */ 205 static int 206 ngh_rcvdata(hook_p hook, item_p item) 207 { 208 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 209 210 hip->stats.frames++; 211 hip->stats.octets += NGI_M(item)->m_pkthdr.len; 212 NG_FREE_ITEM(item); 213 return 0; 214 } 215 216 /* 217 * Hook disconnection 218 */ 219 static int 220 ngh_disconnect(hook_p hook) 221 { 222 223 kfree(NG_HOOK_PRIVATE(hook), M_NETGRAPH); 224 NG_HOOK_SET_PRIVATE(hook, NULL); 225 if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 226 ng_rmnode_self(NG_HOOK_NODE(hook)); 227 return (0); 228 } 229