xref: /netbsd-src/usr.sbin/ldpd/pdu.c (revision c2f76ff004a2cb67efe5b12d97bd3ef7fe89e18d)
1 /* $NetBSD: pdu.c,v 1.1 2010/12/08 07:20:15 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 
45 uint
46 get_pdu(unsigned char *s, struct ldp_pdu * p)
47 {
48 	struct ldp_pdu *p1;
49 	p1 = (struct ldp_pdu *) s;
50 
51 	p->version = ntohs(p1->version);
52 	p->length = ntohs(p1->length);
53 	memcpy(&p->ldp_id, &p1->ldp_id, sizeof(struct in_addr));
54 	p->label_space = ntohs(p1->label_space);
55 
56 	return MIN_PDU_SIZE;
57 }
58 
59 /* Checks an incoming PDU for size and version */
60 int
61 check_recv_pdu(struct ldp_peer * p, struct ldp_pdu * rpdu, int c)
62 {
63 	struct notification_tlv *notiftlv;
64 
65 	/* Avoid underflow */
66 	if (c < MIN_PDU_SIZE)
67 		return LDP_E_BAD_LENGTH;
68 
69 
70 	/* Check PDU for right LDP version */
71 	if (ntohs(rpdu->version) != LDP_VERSION) {
72 		fatalp("Invalid PDU version received from %s (%d)\n",
73 		       inet_ntoa(p->address), ntohs(rpdu->version));
74 		notiftlv = build_notification(0, NOTIF_BAD_LDP_VER);
75 		send_tlv(p, (struct tlv *) notiftlv);
76 		free(notiftlv);
77 		return LDP_E_BAD_VERSION;
78 	}
79 	/* Check PDU for length validity */
80 	if (ntohs(rpdu->length) > c - PDU_VER_LENGTH) {
81 		fatalp("Invalid PDU length received from %s (announced %d, "
82 		    "received %d)\n", inet_ntoa(p->address),
83 		    ntohs(rpdu->length), (int) (c - PDU_VER_LENGTH));
84 		notiftlv = build_notification(0, NOTIF_BAD_PDU_LEN);
85 		send_tlv(p, (struct tlv *) notiftlv);
86 		free(notiftlv);
87 		return LDP_E_BAD_LENGTH;
88 	}
89 	return LDP_E_OK;
90 }
91