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