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 * $Whistle: ng_hole.c,v 1.10 1999/11/01 09:24:51 julian Exp $ 40 */ 41 42 /* 43 * This node is a 'black hole' that simply discards everything it receives 44 */ 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/malloc.h> 50 #include <sys/mbuf.h> 51 #include <netgraph/ng_message.h> 52 #include <netgraph/netgraph.h> 53 #include <netgraph/ng_parse.h> 54 #include <netgraph/ng_hole.h> 55 56 /* Per hook private info. */ 57 struct ng_hole_hookinfo { 58 struct ng_hole_hookstat stats; 59 }; 60 typedef struct ng_hole_hookinfo *hinfo_p; 61 62 /* Parse type for struct ng_hole_hookstat. */ 63 static const struct ng_parse_struct_field ng_hole_hookstat_type_fields[] = 64 NG_HOLE_HOOKSTAT_TYPE_INFO; 65 static const struct ng_parse_type ng_hole_hookstat_type = { 66 &ng_parse_struct_type, 67 &ng_hole_hookstat_type_fields 68 }; 69 70 /* List of commands and how to convert arguments to/from ASCII. */ 71 static const struct ng_cmdlist ng_hole_cmdlist[] = { 72 { 73 NGM_HOLE_COOKIE, 74 NGM_HOLE_GET_STATS, 75 "getstats", 76 &ng_parse_hookbuf_type, 77 &ng_hole_hookstat_type 78 }, 79 { 80 NGM_HOLE_COOKIE, 81 NGM_HOLE_CLR_STATS, 82 "clrstats", 83 &ng_parse_hookbuf_type, 84 NULL 85 }, 86 { 87 NGM_HOLE_COOKIE, 88 NGM_HOLE_GETCLR_STATS, 89 "getclrstats", 90 &ng_parse_hookbuf_type, 91 &ng_hole_hookstat_type 92 }, 93 { 0 } 94 }; 95 96 /* Netgraph methods */ 97 static ng_constructor_t ngh_cons; 98 static ng_rcvmsg_t ngh_rcvmsg; 99 static ng_newhook_t ngh_newhook; 100 static ng_rcvdata_t ngh_rcvdata; 101 static ng_disconnect_t ngh_disconnect; 102 103 static struct ng_type typestruct = { 104 .version = NG_ABI_VERSION, 105 .name = NG_HOLE_NODE_TYPE, 106 .constructor = ngh_cons, 107 .rcvmsg = ngh_rcvmsg, 108 .newhook = ngh_newhook, 109 .rcvdata = ngh_rcvdata, 110 .disconnect = ngh_disconnect, 111 .cmdlist = ng_hole_cmdlist, 112 }; 113 NETGRAPH_INIT(hole, &typestruct); 114 115 /* 116 * Be obliging. but no work to do. 117 */ 118 static int 119 ngh_cons(node_p node) 120 { 121 return(0); 122 } 123 124 /* 125 * Add a hook. 126 */ 127 static int 128 ngh_newhook(node_p node, hook_p hook, const char *name) 129 { 130 hinfo_p hip; 131 132 /* Create hook private structure. */ 133 hip = malloc(sizeof(*hip), M_NETGRAPH, M_NOWAIT | M_ZERO); 134 if (hip == NULL) 135 return (ENOMEM); 136 NG_HOOK_SET_PRIVATE(hook, hip); 137 return (0); 138 } 139 140 /* 141 * Receive a control message. 142 */ 143 static int 144 ngh_rcvmsg(node_p node, item_p item, hook_p lasthook) 145 { 146 struct ng_mesg *msg; 147 struct ng_mesg *resp = NULL; 148 int error = 0; 149 struct ng_hole_hookstat *stats; 150 hook_p hook; 151 152 NGI_GET_MSG(item, msg); 153 switch (msg->header.typecookie) { 154 case NGM_HOLE_COOKIE: 155 switch (msg->header.cmd) { 156 case NGM_HOLE_GET_STATS: 157 case NGM_HOLE_CLR_STATS: 158 case NGM_HOLE_GETCLR_STATS: 159 /* Sanity check. */ 160 if (msg->header.arglen != NG_HOOKSIZ) { 161 error = EINVAL; 162 break; 163 } 164 /* Find hook. */ 165 hook = ng_findhook(node, (char *)msg->data); 166 if (hook == NULL) { 167 error = ENOENT; 168 break; 169 } 170 stats = &((hinfo_p)NG_HOOK_PRIVATE(hook))->stats; 171 /* Build response (if desired). */ 172 if (msg->header.cmd != NGM_HOLE_CLR_STATS) { 173 NG_MKRESPONSE(resp, msg, sizeof(*stats), 174 M_NOWAIT); 175 if (resp == NULL) { 176 error = ENOMEM; 177 break; 178 } 179 bcopy(stats, resp->data, sizeof(*stats)); 180 } 181 /* Clear stats (if desired). */ 182 if (msg->header.cmd != NGM_HOLE_GET_STATS) 183 bzero(stats, sizeof(*stats)); 184 break; 185 default: /* Unknown command. */ 186 error = EINVAL; 187 break; 188 } 189 break; 190 default: /* Unknown type cookie. */ 191 error = EINVAL; 192 break; 193 } 194 NG_RESPOND_MSG(error, node, item, resp); 195 NG_FREE_MSG(msg); 196 return (error); 197 } 198 199 /* 200 * Receive data 201 */ 202 static int 203 ngh_rcvdata(hook_p hook, item_p item) 204 { 205 const hinfo_p hip = NG_HOOK_PRIVATE(hook); 206 207 hip->stats.frames++; 208 hip->stats.octets += NGI_M(item)->m_pkthdr.len; 209 NG_FREE_ITEM(item); 210 return 0; 211 } 212 213 /* 214 * Hook disconnection 215 */ 216 static int 217 ngh_disconnect(hook_p hook) 218 { 219 220 free(NG_HOOK_PRIVATE(hook), M_NETGRAPH); 221 NG_HOOK_SET_PRIVATE(hook, NULL); 222 if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 223 ng_rmnode_self(NG_HOOK_NODE(hook)); 224 return (0); 225 } 226