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
ngh_cons(node_p node)119 ngh_cons(node_p node)
120 {
121 return(0);
122 }
123
124 /*
125 * Add a hook.
126 */
127 static int
ngh_newhook(node_p node,hook_p hook,const char * name)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
ngh_rcvmsg(node_p node,item_p item,hook_p lasthook)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
ngh_rcvdata(hook_p hook,item_p item)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
ngh_disconnect(hook_p hook)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