xref: /freebsd/sys/net/if_mib.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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 
41 /*
42  * A sysctl(3) MIB for generic interface information.  This information
43  * is exported in the net.link.generic branch, which has the following
44  * structure:
45  *
46  * net.link.generic	.system			- system-wide control variables
47  *						  and statistics (node)
48  *			.ifdata.<ifindex>.general
49  *						- what's in `struct ifdata'
50  *						  plus some other info
51  *			.ifdata.<ifindex>.linkspecific
52  *						- a link-type-specific data
53  *						  structure (as might be used
54  *						  by an SNMP agent
55  *
56  * Perhaps someday we will make addresses accessible via this interface
57  * as well (then there will be four such...).  The reason that the
58  * index comes before the last element in the name is because it
59  * seems more orthogonal that way, particularly with the possibility
60  * of other per-interface data living down here as well (e.g., integrated
61  * services stuff).
62  */
63 
64 SYSCTL_DECL(_net_link_generic);
65 SYSCTL_NODE(_net_link_generic, IFMIB_SYSTEM, system, CTLFLAG_RW, 0,
66 	    "Variables global to all interfaces");
67 SYSCTL_INT(_net_link_generic_system, IFMIB_IFCOUNT, ifcount, CTLFLAG_RD,
68 	   &if_index, 0, "Number of configured interfaces");
69 
70 static int
71 sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
72 {
73 	int *name = (int *)arg1;
74 	int error;
75 	u_int namelen = arg2;
76 	struct ifnet *ifp;
77 	struct ifmibdata ifmd;
78 	size_t dlen;
79 	char *dbuf;
80 
81 	if (namelen != 2)
82 		return EINVAL;
83 
84 	if (name[0] <= 0 || name[0] > if_index ||
85 	    ifnet_byindex(name[0]) == NULL)
86 		return ENOENT;
87 
88 	ifp = ifnet_byindex(name[0]);
89 
90 	switch(name[1]) {
91 	default:
92 		return ENOENT;
93 
94 	case IFDATA_GENERAL:
95 		bzero(&ifmd, sizeof(ifmd));
96 		strlcpy(ifmd.ifmd_name, ifp->if_xname, sizeof(ifmd.ifmd_name));
97 
98 #define COPY(fld) ifmd.ifmd_##fld = ifp->if_##fld
99 		COPY(pcount);
100 		COPY(data);
101 #undef COPY
102 		ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
103 		ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
104 		ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
105 		ifmd.ifmd_snd_drops = ifp->if_snd.ifq_drops;
106 
107 		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
108 		if (error || !req->newptr)
109 			return error;
110 
111 		error = SYSCTL_IN(req, &ifmd, sizeof ifmd);
112 		if (error)
113 			return error;
114 
115 #define DONTCOPY(fld) ifmd.ifmd_data.ifi_##fld = ifp->if_data.ifi_##fld
116 		DONTCOPY(type);
117 		DONTCOPY(physical);
118 		DONTCOPY(addrlen);
119 		DONTCOPY(hdrlen);
120 		DONTCOPY(mtu);
121 		DONTCOPY(metric);
122 		DONTCOPY(baudrate);
123 #undef DONTCOPY
124 #define COPY(fld) ifp->if_##fld = ifmd.ifmd_##fld
125 		COPY(data);
126 		ifp->if_snd.ifq_maxlen = ifmd.ifmd_snd_maxlen;
127 		ifp->if_snd.ifq_drops = ifmd.ifmd_snd_drops;
128 #undef COPY
129 		break;
130 
131 	case IFDATA_LINKSPECIFIC:
132 		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
133 		if (error || !req->newptr)
134 			return error;
135 
136 		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
137 		if (error)
138 			return error;
139 
140 	case IFDATA_DRIVERNAME:
141 		/* 20 is enough for 64bit ints */
142 		dlen = strlen(ifp->if_dname) + 20 + 1;
143 		if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL)
144 			return (ENOMEM);
145 		if (ifp->if_dunit == IF_DUNIT_NONE)
146 			strcpy(dbuf, ifp->if_dname);
147 		else
148 			sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
149 
150 		error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
151 		if (error == 0 && req->newptr != NULL)
152 			error = EPERM;
153 		free(dbuf, M_TEMP);
154 		return (error);
155 	}
156 	return 0;
157 }
158 
159 SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata, CTLFLAG_RW,
160 	    sysctl_ifdata, "Interface table");
161 
162