1/* $NetBSD: pdu.c,v 1.4 2013/02/04 17:14:31 kefren Exp $ */
2
3/*-
4 * Copyright (c) 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Mihai Chelaru <kefren@NetBSD.org>
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <arpa/inet.h>
33
34#include <stdio.h>
35#include <strings.h>
36#include <stdlib.h>
37
38#include "socketops.h"
39#include "ldp_errors.h"
40#include "ldp.h"
41#include "ldp_peer.h"
42#include "notifications.h"
43#include "pdu.h"
44
45uint
46get_pdu(const unsigned char *s, struct ldp_pdu * p)
47{
48	const struct ldp_pdu *p1 = (const struct ldp_pdu *) s;
49
50	p->version = ntohs(p1->version);
51	p->length = ntohs(p1->length);
52	memcpy(&p->ldp_id, &p1->ldp_id, sizeof(struct in_addr));
53	p->label_space = ntohs(p1->label_space);
54
55	return MIN_PDU_SIZE;
56}
57
58/* Checks an incoming PDU for size and version */
59int
60check_recv_pdu(const struct ldp_peer * p, const struct ldp_pdu * rpdu, int c)
61{
62	struct notification_tlv *notiftlv;
63
64	/* Avoid underflow */
65	if (c < MIN_PDU_SIZE)
66		return LDP_E_BAD_LENGTH;
67
68	if (p->ldp_id.s_addr != rpdu->ldp_id.s_addr) {
69		fatalp("Invalid LDP ID %s received from ",
70		    inet_ntoa(rpdu->ldp_id));
71		fatalp("%s\n", inet_ntoa(p->ldp_id));
72		notiftlv = build_notification(0,
73		    NOTIF_FATAL | NOTIF_BAD_LDP_ID);
74		send_tlv(p, (struct tlv *) notiftlv);
75		free(notiftlv);
76		return LDP_E_BAD_ID;
77	}
78
79	/* Check PDU for right LDP version */
80	if (ntohs(rpdu->version) != LDP_VERSION) {
81		fatalp("Invalid PDU version received from %s (%d)\n",
82		       satos(p->address), ntohs(rpdu->version));
83		notiftlv = build_notification(0,
84		    NOTIF_FATAL | NOTIF_BAD_LDP_VER);
85		send_tlv(p, (struct tlv *) notiftlv);
86		free(notiftlv);
87		return LDP_E_BAD_VERSION;
88	}
89	/* Check PDU for length validity */
90	if (ntohs(rpdu->length) > c - PDU_VER_LENGTH) {
91		fatalp("Invalid PDU length received from %s (announced %d, "
92		    "received %d)\n", satos(p->address),
93		    ntohs(rpdu->length), (int) (c - PDU_VER_LENGTH));
94		notiftlv = build_notification(0,
95		    NOTIF_FATAL | NOTIF_BAD_PDU_LEN);
96		send_tlv(p, (struct tlv *) notiftlv);
97		free(notiftlv);
98		return LDP_E_BAD_LENGTH;
99	}
100	return LDP_E_OK;
101}
102