xref: /freebsd-13-stable/sys/net/if_mib.c (revision f8167e0404dab9ffeaca95853dd237ab7c587f82)
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 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/socket.h>
35 #include <sys/sysctl.h>
36 
37 #include <net/if.h>
38 #include <net/if_var.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 static SYSCTL_NODE(_net_link_generic, IFMIB_SYSTEM, system,
67     CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
68     "Variables global to all interfaces");
69 
70 SYSCTL_INT(_net_link_generic_system, IFMIB_IFCOUNT, ifcount,
71 	CTLFLAG_VNET | CTLFLAG_RD, &VNET_NAME(if_index), 0,
72 	"Number of configured interfaces");
73 
74 static int
sysctl_ifdata(SYSCTL_HANDLER_ARGS)75 sysctl_ifdata(SYSCTL_HANDLER_ARGS) /* XXX bad syntax! */
76 {
77 	int *name = (int *)arg1;
78 	int error;
79 	u_int namelen = arg2;
80 	struct ifnet *ifp;
81 	struct ifmibdata ifmd;
82 	struct epoch_tracker et;
83 	size_t dlen;
84 	char *dbuf;
85 
86 	if (namelen != 2)
87 		return EINVAL;
88 	if (name[0] <= 0)
89 		return (ENOENT);
90 	NET_EPOCH_ENTER(et);
91 	ifp = ifnet_byindex_ref(name[0]);
92 	NET_EPOCH_EXIT(et);
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 		ifmd.ifmd_pcount = ifp->if_pcount;
106 		if_data_copy(ifp, &ifmd.ifmd_data);
107 
108 		ifmd.ifmd_flags = ifp->if_flags | ifp->if_drv_flags;
109 		ifmd.ifmd_snd_len = ifp->if_snd.ifq_len;
110 		ifmd.ifmd_snd_maxlen = ifp->if_snd.ifq_maxlen;
111 		ifmd.ifmd_snd_drops =
112 		    ifp->if_get_counter(ifp, IFCOUNTER_OQDROPS);
113 
114 		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
115 		if (error)
116 			goto out;
117 		break;
118 
119 	case IFDATA_LINKSPECIFIC:
120 		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
121 		if (error || !req->newptr)
122 			goto out;
123 		break;
124 
125 	case IFDATA_DRIVERNAME:
126 		/* 20 is enough for 64bit ints */
127 		dlen = strlen(ifp->if_dname) + 20 + 1;
128 		if ((dbuf = malloc(dlen, M_TEMP, M_NOWAIT)) == NULL) {
129 			error = ENOMEM;
130 			goto out;
131 		}
132 		if (ifp->if_dunit == IF_DUNIT_NONE)
133 			strcpy(dbuf, ifp->if_dname);
134 		else
135 			sprintf(dbuf, "%s%d", ifp->if_dname, ifp->if_dunit);
136 
137 		error = SYSCTL_OUT(req, dbuf, strlen(dbuf) + 1);
138 		if (error == 0 && req->newptr != NULL)
139 			error = EPERM;
140 		free(dbuf, M_TEMP);
141 		goto out;
142 	}
143 out:
144 	if_rele(ifp);
145 	return error;
146 }
147 
148 static SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata,
149     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ifdata,
150     "Interface table");
151