xref: /freebsd/sys/net/if_mib.c (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
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  * $FreeBSD$
30  */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/socket.h>
36 #include <sys/sysctl.h>
37 
38 #include <net/if.h>
39 #include <net/if_mib.h>
40 #include <net/vnet.h>
41 
42 /*
43  * A sysctl(3) MIB for generic interface information.  This information
44  * is exported in the net.link.generic branch, which has the following
45  * structure:
46  *
47  * net.link.generic	.system			- system-wide control variables
48  *						  and statistics (node)
49  *			.ifdata.<ifindex>.general
50  *						- what's in `struct ifdata'
51  *						  plus some other info
52  *			.ifdata.<ifindex>.linkspecific
53  *						- a link-type-specific data
54  *						  structure (as might be used
55  *						  by an SNMP agent
56  *
57  * Perhaps someday we will make addresses accessible via this interface
58  * as well (then there will be four such...).  The reason that the
59  * index comes before the last element in the name is because it
60  * seems more orthogonal that way, particularly with the possibility
61  * of other per-interface data living down here as well (e.g., integrated
62  * services stuff).
63  */
64 
65 SYSCTL_DECL(_net_link_generic);
66 SYSCTL_NODE(_net_link_generic, IFMIB_SYSTEM, system, CTLFLAG_RW, 0,
67 	    "Variables global to all interfaces");
68 
69 SYSCTL_VNET_INT(_net_link_generic_system, IFMIB_IFCOUNT, ifcount, CTLFLAG_RD,
70 	    &VNET_NAME(if_index), 0,
71 	     "Number of configured interfaces");
72 
73 static int
74 sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
75 {
76 	int *name = (int *)arg1;
77 	int error;
78 	u_int namelen = arg2;
79 	struct ifnet *ifp;
80 	struct ifmibdata ifmd;
81 	size_t dlen;
82 	char *dbuf;
83 
84 	if (namelen != 2)
85 		return EINVAL;
86 	if (name[0] <= 0)
87 		return (ENOENT);
88 	ifp = ifnet_byindex_ref(name[0]);
89 	if (ifp == NULL)
90 		return (ENOENT);
91 
92 	switch(name[1]) {
93 	default:
94 		error = ENOENT;
95 		goto out;
96 
97 	case IFDATA_GENERAL:
98 		bzero(&ifmd, sizeof(ifmd));
99 		strlcpy(ifmd.ifmd_name, ifp->if_xname, sizeof(ifmd.ifmd_name));
100 
101 #define COPY(fld) ifmd.ifmd_##fld = ifp->if_##fld
102 		COPY(pcount);
103 		COPY(data);
104 #undef COPY
105 		ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
106 		ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
107 		ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
108 		ifmd.ifmd_snd_drops = ifp->if_snd.ifq_drops;
109 
110 		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
111 		if (error || !req->newptr)
112 			goto out;
113 
114 		error = SYSCTL_IN(req, &ifmd, sizeof ifmd);
115 		if (error)
116 			goto out;
117 
118 #define DONTCOPY(fld) ifmd.ifmd_data.ifi_##fld = ifp->if_data.ifi_##fld
119 		DONTCOPY(type);
120 		DONTCOPY(physical);
121 		DONTCOPY(addrlen);
122 		DONTCOPY(hdrlen);
123 		DONTCOPY(mtu);
124 		DONTCOPY(metric);
125 		DONTCOPY(baudrate);
126 #undef DONTCOPY
127 #define COPY(fld) ifp->if_##fld = ifmd.ifmd_##fld
128 		COPY(data);
129 		ifp->if_snd.ifq_maxlen = ifmd.ifmd_snd_maxlen;
130 		ifp->if_snd.ifq_drops = ifmd.ifmd_snd_drops;
131 #undef COPY
132 		break;
133 
134 	case IFDATA_LINKSPECIFIC:
135 		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
136 		if (error || !req->newptr)
137 			goto out;
138 
139 		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
140 		if (error)
141 			goto out;
142 		break;
143 
144 	case IFDATA_DRIVERNAME:
145 		/* 20 is enough for 64bit ints */
146 		dlen = strlen(ifp->if_dname) + 20 + 1;
147 		if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL) {
148 			error = ENOMEM;
149 			goto out;
150 		}
151 		if (ifp->if_dunit == IF_DUNIT_NONE)
152 			strcpy(dbuf, ifp->if_dname);
153 		else
154 			sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
155 
156 		error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
157 		if (error == 0 && req->newptr != NULL)
158 			error = EPERM;
159 		free(dbuf, M_TEMP);
160 		goto out;
161 	}
162 out:
163 	if_rele(ifp);
164 	return error;
165 }
166 
167 SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata, CTLFLAG_RW,
168 	    sysctl_ifdata, "Interface table");
169 
170