xref: /freebsd/sys/net/if_mib.c (revision 6356dba0b403daa023dec24559ab1f8e602e4f14)
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 #include <sys/vimage.h>
38 
39 #include <net/if.h>
40 #include <net/if_mib.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 SYSCTL_INT(_net_link_generic_system, IFMIB_IFCOUNT, ifcount, CTLFLAG_RD,
69 	   &if_index, 0, "Number of configured interfaces");
70 
71 static int
72 sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
73 {
74 	int *name = (int *)arg1;
75 	int error;
76 	u_int namelen = arg2;
77 	struct ifnet *ifp;
78 	struct ifmibdata ifmd;
79 	size_t dlen;
80 	char *dbuf;
81 
82 	if (namelen != 2)
83 		return EINVAL;
84 
85 	if (name[0] <= 0 || name[0] > V_if_index ||
86 	    ifnet_byindex(name[0]) == NULL)
87 		return ENOENT;
88 
89 	ifp = ifnet_byindex(name[0]);
90 
91 	switch(name[1]) {
92 	default:
93 		return ENOENT;
94 
95 	case IFDATA_GENERAL:
96 		bzero(&ifmd, sizeof(ifmd));
97 		strlcpy(ifmd.ifmd_name, ifp->if_xname, sizeof(ifmd.ifmd_name));
98 
99 #define COPY(fld) ifmd.ifmd_##fld = ifp->if_##fld
100 		COPY(pcount);
101 		COPY(data);
102 #undef COPY
103 		ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
104 		ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
105 		ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
106 		ifmd.ifmd_snd_drops = ifp->if_snd.ifq_drops;
107 
108 		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
109 		if (error || !req->newptr)
110 			return error;
111 
112 		error = SYSCTL_IN(req, &ifmd, sizeof ifmd);
113 		if (error)
114 			return error;
115 
116 #define DONTCOPY(fld) ifmd.ifmd_data.ifi_##fld = ifp->if_data.ifi_##fld
117 		DONTCOPY(type);
118 		DONTCOPY(physical);
119 		DONTCOPY(addrlen);
120 		DONTCOPY(hdrlen);
121 		DONTCOPY(mtu);
122 		DONTCOPY(metric);
123 		DONTCOPY(baudrate);
124 #undef DONTCOPY
125 #define COPY(fld) ifp->if_##fld = ifmd.ifmd_##fld
126 		COPY(data);
127 		ifp->if_snd.ifq_maxlen = ifmd.ifmd_snd_maxlen;
128 		ifp->if_snd.ifq_drops = ifmd.ifmd_snd_drops;
129 #undef COPY
130 		break;
131 
132 	case IFDATA_LINKSPECIFIC:
133 		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
134 		if (error || !req->newptr)
135 			return error;
136 
137 		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
138 		if (error)
139 			return error;
140 
141 	case IFDATA_DRIVERNAME:
142 		/* 20 is enough for 64bit ints */
143 		dlen = strlen(ifp->if_dname) + 20 + 1;
144 		if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL)
145 			return (ENOMEM);
146 		if (ifp->if_dunit == IF_DUNIT_NONE)
147 			strcpy(dbuf, ifp->if_dname);
148 		else
149 			sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
150 
151 		error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
152 		if (error == 0 && req->newptr != NULL)
153 			error = EPERM;
154 		free(dbuf, M_TEMP);
155 		return (error);
156 	}
157 	return 0;
158 }
159 
160 SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata, CTLFLAG_RW,
161 	    sysctl_ifdata, "Interface table");
162 
163