xref: /netbsd-src/usr.sbin/ldpd/pdu.c (revision 2cc7bf11fa5d84a8e6637f5bdd44aba04994b0de)
1 /* $NetBSD: pdu.c,v 1.5 2013/07/11 05:45:23 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
get_pdu(const unsigned char * s,struct ldp_pdu * p)46 get_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 */
59 int
check_recv_pdu(const struct ldp_peer * p,const struct ldp_pdu * rpdu,int c)60 check_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