if_mib.c revision 191688 
1/*-
2 * Copyright 1996 Massachusetts Institute of Technology
3 *
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission.  M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose.  It is provided "as is" without express or implied
14 * warranty.
15 *
16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: head/sys/net/if_mib.c 191688 2009-04-30 13:36:26Z zec $
30 */
31
32#include "opt_route.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/socket.h>
38#include <sys/sysctl.h>
39#include <sys/vimage.h>
40
41#include <net/if.h>
42#include <net/if_mib.h>
43#include <net/route.h>
44#include <net/vnet.h>
45
46/*
47 * A sysctl(3) MIB for generic interface information.  This information
48 * is exported in the net.link.generic branch, which has the following
49 * structure:
50 *
51 * net.link.generic	.system			- system-wide control variables
52 *						  and statistics (node)
53 *			.ifdata.<ifindex>.general
54 *						- what's in `struct ifdata'
55 *						  plus some other info
56 *			.ifdata.<ifindex>.linkspecific
57 *						- a link-type-specific data
58 *						  structure (as might be used
59 *						  by an SNMP agent
60 *
61 * Perhaps someday we will make addresses accessible via this interface
62 * as well (then there will be four such...).  The reason that the
63 * index comes before the last element in the name is because it
64 * seems more orthogonal that way, particularly with the possibility
65 * of other per-interface data living down here as well (e.g., integrated
66 * services stuff).
67 */
68
69SYSCTL_DECL(_net_link_generic);
70SYSCTL_NODE(_net_link_generic, IFMIB_SYSTEM, system, CTLFLAG_RW, 0,
71	    "Variables global to all interfaces");
72
73SYSCTL_V_INT(V_NET, vnet_net, _net_link_generic_system, IFMIB_IFCOUNT,
74	     ifcount, CTLFLAG_RD, if_index, 0,
75	     "Number of configured interfaces");
76
77static int
78sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
79{
80	int *name = (int *)arg1;
81	int error;
82	u_int namelen = arg2;
83	struct ifnet *ifp;
84	struct ifmibdata ifmd;
85	size_t dlen;
86	char *dbuf;
87
88	if (namelen != 2)
89		return EINVAL;
90	if (name[0] <= 0)
91		return (ENOENT);
92	ifp = ifnet_byindex_ref(name[0]);
93	if (ifp == NULL)
94		return (ENOENT);
95
96	switch(name[1]) {
97	default:
98		error = ENOENT;
99		goto out;
100
101	case IFDATA_GENERAL:
102		bzero(&ifmd, sizeof(ifmd));
103		strlcpy(ifmd.ifmd_name, ifp->if_xname, sizeof(ifmd.ifmd_name));
104
105#define COPY(fld) ifmd.ifmd_##fld = ifp->if_##fld
106		COPY(pcount);
107		COPY(data);
108#undef COPY
109		ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
110		ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
111		ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
112		ifmd.ifmd_snd_drops = ifp->if_snd.ifq_drops;
113
114		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
115		if (error || !req->newptr)
116			goto out;
117
118		error = SYSCTL_IN(req, &ifmd, sizeof ifmd);
119		if (error)
120			goto out;
121
122#define DONTCOPY(fld) ifmd.ifmd_data.ifi_##fld = ifp->if_data.ifi_##fld
123		DONTCOPY(type);
124		DONTCOPY(physical);
125		DONTCOPY(addrlen);
126		DONTCOPY(hdrlen);
127		DONTCOPY(mtu);
128		DONTCOPY(metric);
129		DONTCOPY(baudrate);
130#undef DONTCOPY
131#define COPY(fld) ifp->if_##fld = ifmd.ifmd_##fld
132		COPY(data);
133		ifp->if_snd.ifq_maxlen = ifmd.ifmd_snd_maxlen;
134		ifp->if_snd.ifq_drops = ifmd.ifmd_snd_drops;
135#undef COPY
136		break;
137
138	case IFDATA_LINKSPECIFIC:
139		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
140		if (error || !req->newptr)
141			goto out;
142
143		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
144		if (error)
145			goto out;
146		break;
147
148	case IFDATA_DRIVERNAME:
149		/* 20 is enough for 64bit ints */
150		dlen = strlen(ifp->if_dname) + 20 + 1;
151		if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL) {
152			error = ENOMEM;
153			goto out;
154		}
155		if (ifp->if_dunit == IF_DUNIT_NONE)
156			strcpy(dbuf, ifp->if_dname);
157		else
158			sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
159
160		error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
161		if (error == 0 && req->newptr != NULL)
162			error = EPERM;
163		free(dbuf, M_TEMP);
164		goto out;
165	}
166out:
167	if_rele(ifp);
168	return error;
169}
170
171SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata, CTLFLAG_RW,
172	    sysctl_ifdata, "Interface table");
173
174