/contrib/bsnmp/snmp_mibII/mibII_nettomedia.c

  1/*
  2 * Copyright (c) 2001-2003
  3 *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
  4 *	All rights reserved.
  5 *
  6 * Author: Harti Brandt <harti@freebsd.org>
  7 * 
  8 * Redistribution and use in source and binary forms, with or without
  9 * modification, are permitted provided that the following conditions
 10 * are met:
 11 * 1. Redistributions of source code must retain the above copyright
 12 *    notice, this list of conditions and the following disclaimer.
 13 * 2. Redistributions in binary form must reproduce the above copyright
 14 *    notice, this list of conditions and the following disclaimer in the
 15 *    documentation and/or other materials provided with the distribution.
 16 * 
 17 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 20 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 27 * SUCH DAMAGE.
 28 *
 29 * $Begemot: bsnmp/snmp_mibII/mibII_nettomedia.c,v 1.8 2004/08/06 08:47:03 brandt Exp $
 30 *
 31 * Read-only implementation of the Arp table (ipNetToMediaTable)
 32 *
 33 * The problem with the table is, that we don't receive routing message
 34 * when a) an arp table entry is resolved and b) when an arp table entry is
 35 * deleted automatically. Therefor we need to poll the table from time to
 36 * time.
 37 */
 38#include "mibII.h"
 39#include "mibII_oid.h"
 40
 41#define ARPREFRESH	30
 42
 43struct mibarp *
 44mib_find_arp(const struct mibif *ifp, struct in_addr in)
 45{
 46	struct mibarp *at;
 47	uint32_t a = ntohl(in.s_addr);
 48
 49	if (get_ticks() >= mibarpticks + ARPREFRESH)
 50		mib_arp_update();
 51
 52	TAILQ_FOREACH(at, &mibarp_list, link)
 53		if (at->index.subs[0] == ifp->index &&
 54		    (at->index.subs[1] == ((a >> 24) & 0xff)) &&
 55		    (at->index.subs[2] == ((a >> 16) & 0xff)) &&
 56		    (at->index.subs[3] == ((a >>  8) & 0xff)) &&
 57		    (at->index.subs[4] == ((a >>  0) & 0xff)))
 58			return (at);
 59	return (NULL);
 60}
 61
 62struct mibarp *
 63mib_arp_create(const struct mibif *ifp, struct in_addr in, const u_char *phys,
 64    size_t physlen)
 65{
 66	struct mibarp *at;
 67	uint32_t a = ntohl(in.s_addr);
 68
 69	if ((at = malloc(sizeof(*at))) == NULL)
 70		return (NULL);
 71	at->flags = 0;
 72
 73	at->index.len = 5;
 74	at->index.subs[0] = ifp->index;
 75	at->index.subs[1] = (a >> 24) & 0xff;
 76	at->index.subs[2] = (a >> 16) & 0xff;
 77	at->index.subs[3] = (a >>  8) & 0xff;
 78	at->index.subs[4] = (a >>  0) & 0xff;
 79	if ((at->physlen = physlen) > sizeof(at->phys))
 80		at->physlen = sizeof(at->phys);
 81	memcpy(at->phys, phys, at->physlen);
 82
 83	INSERT_OBJECT_OID(at, &mibarp_list);
 84
 85	return (at);
 86}
 87
 88void
 89mib_arp_delete(struct mibarp *at)
 90{
 91	TAILQ_REMOVE(&mibarp_list, at, link);
 92	free(at);
 93}
 94
 95int
 96op_nettomedia(struct snmp_context *ctx __unused, struct snmp_value *value,
 97    u_int sub, u_int iidx __unused, enum snmp_op op)
 98{
 99	struct mibarp *at;
100
101	at = NULL;	/* gcc */
102
103	if (get_ticks() >= mibarpticks + ARPREFRESH)
104		mib_arp_update();
105
106	switch (op) {
107
108	  case SNMP_OP_GETNEXT:
109		if ((at = NEXT_OBJECT_OID(&mibarp_list, &value->var, sub)) == NULL)
110			return (SNMP_ERR_NOSUCHNAME);
111		index_append(&value->var, sub, &at->index);
112		break;
113
114	  case SNMP_OP_GET:
115		if ((at = FIND_OBJECT_OID(&mibarp_list, &value->var, sub)) == NULL)
116			return (SNMP_ERR_NOSUCHNAME);
117		break;
118
119	  case SNMP_OP_SET:
120		if ((at = FIND_OBJECT_OID(&mibarp_list, &value->var, sub)) == NULL)
121			return (SNMP_ERR_NO_CREATION);
122		return (SNMP_ERR_NOT_WRITEABLE);
123
124	  case SNMP_OP_ROLLBACK:
125	  case SNMP_OP_COMMIT:
126		abort();
127	}
128
129	switch (value->var.subs[sub - 1]) {
130
131	  case LEAF_ipNetToMediaIfIndex:
132		value->v.integer = at->index.subs[0];
133		break;
134
135	  case LEAF_ipNetToMediaPhysAddress:
136		return (string_get(value, at->phys, at->physlen));
137
138	  case LEAF_ipNetToMediaNetAddress:
139		value->v.ipaddress[0] = at->index.subs[1];
140		value->v.ipaddress[1] = at->index.subs[2];
141		value->v.ipaddress[2] = at->index.subs[3];
142		value->v.ipaddress[3] = at->index.subs[4];
143		break;
144
145	  case LEAF_ipNetToMediaType:
146		value->v.integer = (at->flags & MIBARP_PERM) ? 4 : 3;
147		break;
148	}
149	return (SNMP_ERR_NOERROR);
150}