* Copyright (c) 2007-2011 Grégoire Henry, Juliusz Chroboczek

/*
* Copyright (c) 2007-2011 Grégoire Henry, Juliusz Chroboczek
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: print-babel.c,v 1.6 2024/09/02 16:15:30 christos Exp $");
#endif

/* \summary: Babel Routing Protocol printer */
/* Specifications:
*
* RFC 6126
* RFC 7298
* RFC 7557
* draft-ietf-babel-rfc6126bis-17
* draft-ietf-babel-hmac-10
* draft-ietf-babel-source-specific-0
*/

#include <config.h>

#include "netdissect-stdinc.h"

#include <stdio.h>
#include <string.h>

#include "netdissect.h"
#include "addrtoname.h"
#include "extract.h"

static void babel_print_v2(netdissect_options *, const u_char *cp, u_int length);

void
babel_print(netdissect_options *ndo,
const u_char *cp, u_int length)
{
ndo->ndo_protocol = "babel";
ND_PRINT("babel");

ND_TCHECK_4(cp);

if(GET_U_1(cp) != 42) {
ND_PRINT(" invalid header");
return;
} else {
ND_PRINT(" %u", GET_U_1(cp + 1));
}

switch(GET_U_1(cp + 1)) {
case 2:
babel_print_v2(ndo, cp, length);
break;
default:
ND_PRINT(" unknown version");
break;
}

return;

trunc:
nd_print_trunc(ndo);
}

/* TLVs */
#define MESSAGE_PAD1 0
#define MESSAGE_PADN 1
#define MESSAGE_ACK_REQ 2
#define MESSAGE_ACK 3
#define MESSAGE_HELLO 4
#define MESSAGE_IHU 5
#define MESSAGE_ROUTER_ID 6
#define MESSAGE_NH 7
#define MESSAGE_UPDATE 8
#define MESSAGE_ROUTE_REQUEST 9
#define MESSAGE_SEQNO_REQUEST 10
#define MESSAGE_TSPC 11
#define MESSAGE_HMAC 12
#define MESSAGE_UPDATE_SRC_SPECIFIC 13 /* last appearance in draft-boutier-babel-source-specific-01 */
#define MESSAGE_REQUEST_SRC_SPECIFIC 14 /* idem */
#define MESSAGE_MH_REQUEST_SRC_SPECIFIC 15 /* idem */
#define MESSAGE_MAC 16
#define MESSAGE_PC 17
#define MESSAGE_CHALLENGE_REQUEST 18
#define MESSAGE_CHALLENGE_REPLY 19

/* sub-TLVs */
#define MESSAGE_SUB_PAD1 0
#define MESSAGE_SUB_PADN 1
#define MESSAGE_SUB_DIVERSITY 2
#define MESSAGE_SUB_TIMESTAMP 3

/* "Mandatory" bit in sub-TLV types */
#define MANDATORY_MASK 0x80

/* Flags for the Hello TLV */
#define UNICAST_MASK 0x8000

/* Diversity sub-TLV channel codes */
static const struct tok diversity_str[] = {
{ 0, "reserved" },
{ 255, "all" },
{ 0, NULL }
};

static const char *
format_id(netdissect_options *ndo, const u_char *id)
{
static char buf[25];
snprintf(buf, 25, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
GET_U_1(id), GET_U_1(id + 1), GET_U_1(id + 2),
GET_U_1(id + 3), GET_U_1(id + 4), GET_U_1(id + 5),
GET_U_1(id + 6), GET_U_1(id + 7));
buf[24] = '\0';
return buf;
}

static const unsigned char v4prefix[16] =
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };

static const char *
format_prefix(netdissect_options *ndo, const u_char *prefix, unsigned char plen)
{
static char buf[50];

/*
* prefix points to a buffer on the stack into which the prefix has
* been placed, so we can't use GET_IPADDR_STRING() or
* GET_IP6ADDR_STRING() on it.
*/
if(plen >= 96 && memcmp(prefix, v4prefix, 12) == 0)
snprintf(buf, 50, "%s/%u", ipaddr_string(ndo, prefix + 12), plen - 96);
else
snprintf(buf, 50, "%s/%u", ip6addr_string(ndo, prefix), plen);
buf[49] = '\0';
return buf;
}

static const char *
format_address(netdissect_options *ndo, const u_char *prefix)
{
/*
* prefix points to a buffer on the stack into which the prefix has
* been placed, so we can't use GET_IPADDR_STRING() or
* GET_IP6ADDR_STRING() on it.
*/
if(memcmp(prefix, v4prefix, 12) == 0)
return ipaddr_string(ndo, prefix + 12);
else
return ip6addr_string(ndo, prefix);
}

static const char *
format_interval(const uint16_t i)
{
static char buf[sizeof("000.00s")];

if (i == 0)
return "0.0s (bogus)";
snprintf(buf, sizeof(buf), "%u.%02us", i / 100, i % 100);
return buf;
}

static const char *
format_interval_update(const uint16_t i)
{
return i == 0xFFFF ? "infinity" : format_interval(i);
}

static const char *
format_timestamp(const uint32_t i)
{
static char buf[sizeof("0000.000000s")];
snprintf(buf, sizeof(buf), "%u.%06us", i / 1000000, i % 1000000);
return buf;
}

/* Return number of octets consumed from the input buffer (not the prefix length
* in bytes), or -1 for encoding error. */
static int
network_prefix(int ae, int plen, unsigned int omitted,
const unsigned char *p, const unsigned char *dp,
unsigned int len, unsigned char *p_r)
{
unsigned pb;
unsigned char prefix[16];
int consumed = 0;

if(plen >= 0)
pb = (plen + 7) / 8;
else if(ae == 1)
pb = 4;
else
pb = 16;

if(pb > 16)
return -1;

memset(prefix, 0, 16);

switch(ae) {
case 0: break;
case 1:
if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted))
return -1;
memcpy(prefix, v4prefix, 12);
if(omitted) {
if (dp == NULL) return -1;
memcpy(prefix, dp, 12 + omitted);
}
if(pb > omitted) {
memcpy(prefix + 12 + omitted, p, pb - omitted);
consumed = pb - omitted;
}
break;
case 2:
if(omitted > 16 || (pb > omitted && len < pb - omitted))
return -1;
if(omitted) {
if (dp == NULL) return -1;
memcpy(prefix, dp, omitted);
}
if(pb > omitted) {
memcpy(prefix + omitted, p, pb - omitted);
consumed = pb - omitted;
}
break;
case 3:
if(pb > 8 && len < pb - 8) return -1;
prefix[0] = 0xfe;
prefix[1] = 0x80;
if(pb > 8) {
memcpy(prefix + 8, p, pb - 8);
consumed = pb - 8;
}
break;
default:
return -1;
}

memcpy(p_r, prefix, 16);
return consumed;
}

static int
network_address(int ae, const unsigned char *a, unsigned int len,
unsigned char *a_r)
{
return network_prefix(ae, -1, 0, a, NULL, len, a_r);
}

/*
* Sub-TLVs consume the "extra data" of Babel TLVs (see Section 4.3 of RFC6126),
* their encoding is similar to the encoding of TLVs, but the type namespace is
* different:
*
* o Type 0 stands for Pad1 sub-TLV with the same encoding as the Pad1 TLV.
* o Type 1 stands for PadN sub-TLV with the same encoding as the PadN TLV.
* o Type 2 stands for Diversity sub-TLV, which propagates diversity routing
* data. Its body is a variable-length sequence of 8-bit unsigned integers,
* each representing per-hop number of interfering radio channel for the
* prefix. Channel 0 is invalid and must not be used in the sub-TLV, channel
* 255 interferes with any other channel.
* o Type 3 stands for Timestamp sub-TLV, used to compute RTT between
* neighbours. In the case of a Hello TLV, the body stores a 32-bits
* timestamp, while in the case of a IHU TLV, two 32-bits timestamps are
* stored.
*
* Sub-TLV types 0 and 1 are valid for any TLV type, whether sub-TLV type 2 is
* only valid for TLV type 8 (Update). Note that within an Update TLV a missing
* Diversity sub-TLV is not the same as a Diversity sub-TLV with an empty body.
* The former would mean a lack of any claims about the interference, and the
* latter would state that interference is definitely absent.
* A type 3 sub-TLV is valid both for Hello and IHU TLVs, though the exact
* semantic of the sub-TLV is different in each case.
*/
static void
subtlvs_print(netdissect_options *ndo,
const u_char *cp, const u_char *ep, const uint8_t tlv_type)
{
uint8_t subtype, sublen;
const char *sep;
uint32_t t1, t2;

while (cp < ep) {
subtype = GET_U_1(cp);
cp++;
if(subtype == MESSAGE_SUB_PAD1) {
ND_PRINT(" sub-pad1");
continue;
}
if ((MANDATORY_MASK & subtype) != 0)
ND_PRINT(" (M)");
if(cp == ep)
goto invalid;
sublen = GET_U_1(cp);
cp++;
if(cp + sublen > ep)
goto invalid;

switch(subtype) {
case MESSAGE_SUB_PADN:
ND_PRINT(" sub-padn");
cp += sublen;
break;
case MESSAGE_SUB_DIVERSITY:
ND_PRINT(" sub-diversity");
if (sublen == 0) {
ND_PRINT(" empty");
break;
}
sep = " ";
while (sublen) {
ND_PRINT("%s%s", sep,
tok2str(diversity_str, "%u", GET_U_1(cp)));
cp++;
sep = "-";
sublen--;
}
if(tlv_type != MESSAGE_UPDATE &&
tlv_type != MESSAGE_UPDATE_SRC_SPECIFIC)
ND_PRINT(" (bogus)");
break;
case MESSAGE_SUB_TIMESTAMP:
ND_PRINT(" sub-timestamp");
if(tlv_type == MESSAGE_HELLO) {
if(sublen < 4)
goto invalid;
t1 = GET_BE_U_4(cp);
ND_PRINT(" %s", format_timestamp(t1));
} else if(tlv_type == MESSAGE_IHU) {
if(sublen < 8)
goto invalid;
t1 = GET_BE_U_4(cp);
ND_PRINT(" %s", format_timestamp(t1));
t2 = GET_BE_U_4(cp + 4);
ND_PRINT("|%s", format_timestamp(t2));
} else
ND_PRINT(" (bogus)");
cp += sublen;
break;
default:
ND_PRINT(" sub-unknown-0x%02x", subtype);
cp += sublen;
} /* switch */
} /* while */
return;

invalid:
nd_print_invalid(ndo);
}

#define ICHECK(i, l) \
if ((i) + (l) > tlvs_length || (i) + (l) > packet_length_remaining) \
goto invalid;

static int
babel_print_v2_tlvs(netdissect_options *ndo,
const u_char *cp, u_int tlvs_length,
u_int packet_length_remaining)
{
u_int i;
u_char v4_prefix[16] =
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 };
u_char v6_prefix[16] = {0};

i = 0;
while(i < tlvs_length) {
const u_char *message;
uint8_t type;
u_int len;

message = cp + i;

ICHECK(i, 1);
if((type = GET_U_1(message)) == MESSAGE_PAD1) {
ND_PRINT(ndo->ndo_vflag ? "\n\tPad 1" : " pad1");
i += 1;
continue;
}

ICHECK(i, 2);
ND_TCHECK_2(message);
len = GET_U_1(message + 1);

ICHECK(i, 2 + len);
ND_TCHECK_LEN(message, 2 + len);

switch(type) {
case MESSAGE_PADN: {
if (!ndo->ndo_vflag)
ND_PRINT(" padN");
else
ND_PRINT("\n\tPad %u", len + 2);
}
break;

case MESSAGE_ACK_REQ: {
u_short nonce, interval;
if (!ndo->ndo_vflag)
ND_PRINT(" ack-req");
else {
ND_PRINT("\n\tAcknowledgment Request ");
if(len < 6) goto invalid;
nonce = GET_BE_U_2(message + 4);
interval = GET_BE_U_2(message + 6);
ND_PRINT("%04x %s", nonce, format_interval(interval));
}
}
break;

case MESSAGE_ACK: {
u_short nonce;
if (!ndo->ndo_vflag)
ND_PRINT(" ack");
else {
ND_PRINT("\n\tAcknowledgment ");
if(len < 2) goto invalid;
nonce = GET_BE_U_2(message + 2);
ND_PRINT("%04x", nonce);
}
}
break;

case MESSAGE_HELLO: {
u_short seqno, interval, unicast;
if (!ndo->ndo_vflag)
ND_PRINT(" hello");
else {
ND_PRINT("\n\tHello ");
if(len < 6) goto invalid;
unicast = (GET_BE_U_2(message + 2) & UNICAST_MASK);
seqno = GET_BE_U_2(message + 4);
interval = GET_BE_U_2(message + 6);
if(unicast)
ND_PRINT("(Unicast) ");
ND_PRINT("seqno %u ", seqno);
if(interval!=0)
ND_PRINT("interval %s", format_interval(interval));
else
ND_PRINT("unscheduled");
/* Extra data. */
if(len > 6)
subtlvs_print(ndo, message + 8, message + 2 + len, type);
}
}
break;

case MESSAGE_IHU: {
unsigned short rxcost, interval;
if (!ndo->ndo_vflag)
ND_PRINT(" ihu");
else {
u_char address[16];
u_char ae;
int rc;
ND_PRINT("\n\tIHU ");
if(len < 6) goto invalid;
rxcost = GET_BE_U_2(message + 4);
interval = GET_BE_U_2(message + 6);
ae = GET_U_1(message + 2);
rc = network_address(ae, message + 8,
len - 6, address);
if(rc < 0) { nd_print_trunc(ndo); break; }
ND_PRINT("%s rxcost %u interval %s",
ae == 0 ? "any" : format_address(ndo, address),
rxcost, format_interval(interval));
/* Extra data. */
if((u_int)rc < len - 6)
subtlvs_print(ndo, message + 8 + rc, message + 2 + len,
type);
}
}
break;

case MESSAGE_ROUTER_ID: {
if (!ndo->ndo_vflag)
ND_PRINT(" router-id");
else {
ND_PRINT("\n\tRouter Id");
if(len < 10) goto invalid;
ND_PRINT(" %s", format_id(ndo, message + 4));
}
}
break;

case MESSAGE_NH: {
if (!ndo->ndo_vflag)
ND_PRINT(" nh");
else {
int rc;
u_char ae;
u_char nh[16];
ND_PRINT("\n\tNext Hop");
if(len < 2) goto invalid;
ae = GET_U_1(message + 2);
rc = network_address(ae, message + 4,
len - 2, nh);
if(rc < 0) goto invalid;
ND_PRINT(" %s", ae == 0 ? "invalid AE 0" : format_address(ndo, nh));
}
}
break;

case MESSAGE_UPDATE: {
if (!ndo->ndo_vflag) {
ND_PRINT(" update");
if(len < 10)
goto invalid;
else
ND_PRINT("%s%s%s",
(GET_U_1(message + 3) & 0x80) ? "/prefix": "",
(GET_U_1(message + 3) & 0x40) ? "/id" : "",
(GET_U_1(message + 3) & 0x3f) ? "/unknown" : "");
} else {
u_short interval, seqno, metric;
u_char ae, plen;
int rc;
u_char prefix[16];
ND_PRINT("\n\tUpdate");
if(len < 10) goto invalid;
ae = GET_U_1(message + 2);
plen = GET_U_1(message + 4) + (GET_U_1(message + 2) == 1 ? 96 : 0);
rc = network_prefix(ae,
GET_U_1(message + 4),
GET_U_1(message + 5),
message + 12,
GET_U_1(message + 2) == 1 ? v4_prefix : v6_prefix,
len - 10, prefix);
if(rc < 0) goto invalid;
interval = GET_BE_U_2(message + 6);
seqno = GET_BE_U_2(message + 8);
metric = GET_BE_U_2(message + 10);
ND_PRINT("%s%s%s %s metric %u seqno %u interval %s",
(GET_U_1(message + 3) & 0x80) ? "/prefix": "",
(GET_U_1(message + 3) & 0x40) ? "/id" : "",
(GET_U_1(message + 3) & 0x3f) ? "/unknown" : "",
ae == 0 ? "any" : format_prefix(ndo, prefix, plen),
metric, seqno, format_interval_update(interval));
if(GET_U_1(message + 3) & 0x80) {
if(GET_U_1(message + 2) == 1)
memcpy(v4_prefix, prefix, 16);
else
memcpy(v6_prefix, prefix, 16);
}
/* extra data? */
if((u_int)rc < len - 10)
subtlvs_print(ndo, message + 12 + rc, message + 2 + len, type);
}
}
break;

case MESSAGE_ROUTE_REQUEST: {
if (!ndo->ndo_vflag)
ND_PRINT(" route-request");
else {
int rc;
u_char prefix[16], ae, plen;
ND_PRINT("\n\tRoute Request ");
if(len < 2) goto invalid;
ae = GET_U_1(message + 2);
plen = GET_U_1(message + 3) + (GET_U_1(message + 2) == 1 ? 96 : 0);
rc = network_prefix(ae,
GET_U_1(message + 3), 0,
message + 4, NULL, len - 2, prefix);
if(rc < 0) goto invalid;
ND_PRINT("for %s",
ae == 0 ? "any" : format_prefix(ndo, prefix, plen));
}
}
break;

case MESSAGE_SEQNO_REQUEST : {
if (!ndo->ndo_vflag)
ND_PRINT(" seqno-request");
else {
int rc;
u_short seqno;
u_char prefix[16], ae, plen;
ND_PRINT("\n\tSeqno Request ");
if(len < 14) goto invalid;
ae = GET_U_1(message + 2);
seqno = GET_BE_U_2(message + 4);
rc = network_prefix(ae,
GET_U_1(message + 3), 0,
message + 16, NULL, len - 14, prefix);
if(rc < 0) goto invalid;
plen = GET_U_1(message + 3) + (GET_U_1(message + 2) == 1 ? 96 : 0);
ND_PRINT("(%u hops) for %s seqno %u id %s",
GET_U_1(message + 6),
ae == 0 ? "invalid AE 0" : format_prefix(ndo, prefix, plen),
seqno, format_id(ndo, message + 8));
}
}
break;
case MESSAGE_TSPC :
if (!ndo->ndo_vflag)
ND_PRINT(" tspc");
else {
ND_PRINT("\n\tTS/PC ");
if(len < 6) goto invalid;
ND_PRINT("timestamp %u packetcounter %u",
GET_BE_U_4(message + 4),
GET_BE_U_2(message + 2));
}
break;
case MESSAGE_HMAC : {
if (!ndo->ndo_vflag)
ND_PRINT(" hmac");
else {
unsigned j;
ND_PRINT("\n\tHMAC ");
if(len < 18) goto invalid;
ND_PRINT("key-id %u digest-%u ", GET_BE_U_2(message + 2),
len - 2);
for (j = 0; j < len - 2; j++)
ND_PRINT("%02X", GET_U_1(message + j + 4));
}
}
break;

case MESSAGE_UPDATE_SRC_SPECIFIC : {
if(!ndo->ndo_vflag) {
ND_PRINT(" ss-update");
} else {
u_char prefix[16], src_prefix[16];
u_short interval, seqno, metric;
u_char ae, plen, src_plen, omitted;
int rc;
int parsed_len = 10;
ND_PRINT("\n\tSS-Update");
if(len < 10) goto invalid;
ae = GET_U_1(message + 2);
src_plen = GET_U_1(message + 3);
plen = GET_U_1(message + 4);
omitted = GET_U_1(message + 5);
interval = GET_BE_U_2(message + 6);
seqno = GET_BE_U_2(message + 8);
metric = GET_BE_U_2(message + 10);
rc = network_prefix(ae, plen, omitted, message + 2 + parsed_len,
ae == 1 ? v4_prefix : v6_prefix,
len - parsed_len, prefix);
if(rc < 0) goto invalid;
if(ae == 1)
plen += 96;
parsed_len += rc;
rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len,
NULL, len - parsed_len, src_prefix);
if(rc < 0) goto invalid;
if(ae == 1)
src_plen += 96;
parsed_len += rc;

ND_PRINT(" %s from", format_prefix(ndo, prefix, plen));
ND_PRINT(" %s metric %u seqno %u interval %s",
format_prefix(ndo, src_prefix, src_plen),
metric, seqno, format_interval_update(interval));
/* extra data? */
if((u_int)parsed_len < len)
subtlvs_print(ndo, message + 2 + parsed_len,
message + 2 + len, type);
}
}
break;

case MESSAGE_REQUEST_SRC_SPECIFIC : {
if(!ndo->ndo_vflag)
ND_PRINT(" ss-request");
else {
int rc, parsed_len = 3;
u_char ae, plen, src_plen, prefix[16], src_prefix[16];
ND_PRINT("\n\tSS-Request ");
if(len < 3) goto invalid;
ae = GET_U_1(message + 2);
plen = GET_U_1(message + 3);
src_plen = GET_U_1(message + 4);
rc = network_prefix(ae, plen, 0, message + 2 + parsed_len,
NULL, len - parsed_len, prefix);
if(rc < 0) goto invalid;
if(ae == 1)
plen += 96;
parsed_len += rc;
rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len,
NULL, len - parsed_len, src_prefix);
if(rc < 0) goto invalid;
if(ae == 1)
src_plen += 96;
parsed_len += rc;
if(ae == 0) {
ND_PRINT("for any");
} else {
ND_PRINT("for (%s, ", format_prefix(ndo, prefix, plen));
ND_PRINT("%s)", format_prefix(ndo, src_prefix, src_plen));
}
}
}
break;

case MESSAGE_MH_REQUEST_SRC_SPECIFIC : {
if(!ndo->ndo_vflag)
ND_PRINT(" ss-mh-request");
else {
int rc, parsed_len = 14;
u_short seqno;
u_char ae, plen, src_plen, prefix[16], src_prefix[16], hopc;
const u_char *router_id = NULL;
ND_PRINT("\n\tSS-MH-Request ");
if(len < 14) goto invalid;
ae = GET_U_1(message + 2);
plen = GET_U_1(message + 3);
seqno = GET_BE_U_2(message + 4);
hopc = GET_U_1(message + 6);
src_plen = GET_U_1(message + 7);
router_id = message + 8;
rc = network_prefix(ae, plen, 0, message + 2 + parsed_len,
NULL, len - parsed_len, prefix);
if(rc < 0) goto invalid;
if(ae == 1)
plen += 96;
parsed_len += rc;
rc = network_prefix(ae, src_plen, 0, message + 2 + parsed_len,
NULL, len - parsed_len, src_prefix);
if(rc < 0) goto invalid;
if(ae == 1)
src_plen += 96;
ND_PRINT("(%u hops) for (%s, ",
hopc, format_prefix(ndo, prefix, plen));
ND_PRINT("%s) seqno %u id %s",
format_prefix(ndo, src_prefix, src_plen),
seqno, format_id(ndo, router_id));
}
}
break;

case MESSAGE_MAC: {
if (!ndo->ndo_vflag)
ND_PRINT(" mac");
else {
ND_PRINT("\n\tMAC ");
ND_PRINT("len %u", len);
}
}
break;

case MESSAGE_PC: {
if (!ndo->ndo_vflag)
ND_PRINT(" pc");
else {
ND_PRINT("\n\tPC");
if(len < 4) goto invalid;
ND_PRINT(" value %u",
GET_BE_U_4(message + 2));
ND_PRINT(" index len %u", len-4);
}
}
break;

case MESSAGE_CHALLENGE_REQUEST: {
if (!ndo->ndo_vflag)
ND_PRINT(" challenge_request");
else {
ND_PRINT("\n\tChallenge Request");
if(len > 192) goto invalid;
ND_PRINT(" len %u", len);
}
}
break;

case MESSAGE_CHALLENGE_REPLY: {
if (!ndo->ndo_vflag)
ND_PRINT(" challenge_reply");
else {
ND_PRINT("\n\tChallenge Reply");
if (len > 192) goto invalid;
ND_PRINT(" len %u", len);
}
}
break;

default:
if (!ndo->ndo_vflag)
ND_PRINT(" unknown");
else
ND_PRINT("\n\tUnknown message type %u", type);
}
i += len + 2;
}

return 0; /* OK */

trunc:
return -1; /* packet truncated by capture process */

invalid:
return -2; /* packet is invalid */
}

static void
babel_print_v2(netdissect_options *ndo,
const u_char *cp, u_int length)
{
u_short bodylen;
int ret;

ND_TCHECK_4(cp);
if (length < 4)
goto invalid;
bodylen = GET_BE_U_2(cp + 2);
ND_PRINT(" (%u)", bodylen);
length -= 4;
cp += 4;

/* Process the TLVs in the body */
if (length < bodylen)
goto invalid;
ret = babel_print_v2_tlvs(ndo, cp, bodylen, length);
if (ret == -1)
goto trunc;
if (ret == -2)
goto invalid;
length -= bodylen;
cp += bodylen;

/* If there's a trailer, process the TLVs in the trailer */
if (length != 0) {
if(ndo->ndo_vflag) ND_PRINT("\n\t----");
else ND_PRINT(" |");
ret = babel_print_v2_tlvs(ndo, cp, length, length);
if (ret == -1)
goto trunc;
if (ret == -2)
goto invalid;
}
return;

trunc:
nd_print_trunc(ndo);
return;

invalid:
nd_print_invalid(ndo);
}