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5807acd8ee
tcpdump/print-ldp.c
Guy Harris 351c0ad599 ldp: use a constant 2, not LDP_TLV_ADDRESS_LIST_AFNUM_LEN. 
We already use GET_BE_U_2(), and use 2 in the TLV_TCHECK() call; this
makes it a bit more obvious (if you read TLV_TCHECK()) that the test
makes sure we can subtract from tlv_tlen without underflowing.
2020-05-26 22:15:50 -07:00

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/*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code
* distributions retain the above copyright notice and this paragraph
* in its entirety, and (2) distributions including binary code include
* the above copyright notice and this paragraph in its entirety in
* the documentation or other materials provided with the distribution.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND
* WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
* LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*
* Original code by Hannes Gredler (hannes@gredler.at)
* and Steinar Haug (sthaug@nethelp.no)
*/
/* \summary: Label Distribution Protocol (LDP) printer */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
#include "addrtoname.h"
#include "l2vpn.h"
#include "af.h"
/*
* ldp common header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Version | PDU Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | LDP Identifier |
* + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*
*/
struct ldp_common_header {
nd_uint16_t version;
nd_uint16_t pdu_length;
nd_ipv4 lsr_id;
nd_uint16_t label_space;
};
#define LDP_VERSION 1
/*
* ldp message header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |U| Message Type | Message Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Message ID |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* | Mandatory Parameters |
* + +
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* + +
* | Optional Parameters |
* + +
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
struct ldp_msg_header {
nd_uint16_t type;
nd_uint16_t length;
nd_uint32_t id;
};
#define LDP_MASK_MSG_TYPE(x) ((x)&0x7fff)
#define LDP_MASK_U_BIT(x) ((x)&0x8000)
#define LDP_MSG_NOTIF 0x0001
#define LDP_MSG_HELLO 0x0100
#define LDP_MSG_INIT 0x0200
#define LDP_MSG_KEEPALIVE 0x0201
#define LDP_MSG_ADDRESS 0x0300
#define LDP_MSG_ADDRESS_WITHDRAW 0x0301
#define LDP_MSG_LABEL_MAPPING 0x0400
#define LDP_MSG_LABEL_REQUEST 0x0401
#define LDP_MSG_LABEL_WITHDRAW 0x0402
#define LDP_MSG_LABEL_RELEASE 0x0403
#define LDP_MSG_LABEL_ABORT_REQUEST 0x0404
#define LDP_VENDOR_PRIVATE_MIN 0x3e00
#define LDP_VENDOR_PRIVATE_MAX 0x3eff
#define LDP_EXPERIMENTAL_MIN 0x3f00
#define LDP_EXPERIMENTAL_MAX 0x3fff
static const struct tok ldp_msg_values[] = {
{ LDP_MSG_NOTIF, "Notification" },
{ LDP_MSG_HELLO, "Hello" },
{ LDP_MSG_INIT, "Initialization" },
{ LDP_MSG_KEEPALIVE, "Keepalive" },
{ LDP_MSG_ADDRESS, "Address" },
{ LDP_MSG_ADDRESS_WITHDRAW, "Address Withdraw" },
{ LDP_MSG_LABEL_MAPPING, "Label Mapping" },
{ LDP_MSG_LABEL_REQUEST, "Label Request" },
{ LDP_MSG_LABEL_WITHDRAW, "Label Withdraw" },
{ LDP_MSG_LABEL_RELEASE, "Label Release" },
{ LDP_MSG_LABEL_ABORT_REQUEST, "Label Abort Request" },
{ 0, NULL}
};
#define LDP_MASK_TLV_TYPE(x) ((x)&0x3fff)
#define LDP_MASK_F_BIT(x) ((x)&0x4000)
#define LDP_TLV_FEC 0x0100
#define LDP_TLV_ADDRESS_LIST 0x0101
#define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
#define LDP_TLV_HOP_COUNT 0x0103
#define LDP_TLV_PATH_VECTOR 0x0104
#define LDP_TLV_GENERIC_LABEL 0x0200
#define LDP_TLV_ATM_LABEL 0x0201
#define LDP_TLV_FR_LABEL 0x0202
#define LDP_TLV_STATUS 0x0300
#define LDP_TLV_EXTD_STATUS 0x0301
#define LDP_TLV_RETURNED_PDU 0x0302
#define LDP_TLV_RETURNED_MSG 0x0303
#define LDP_TLV_COMMON_HELLO 0x0400
#define LDP_TLV_IPV4_TRANSPORT_ADDR 0x0401
#define LDP_TLV_CONFIG_SEQ_NUMBER 0x0402
#define LDP_TLV_IPV6_TRANSPORT_ADDR 0x0403
#define LDP_TLV_COMMON_SESSION 0x0500
#define LDP_TLV_ATM_SESSION_PARM 0x0501
#define LDP_TLV_FR_SESSION_PARM 0x0502
#define LDP_TLV_FT_SESSION 0x0503
#define LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
#define LDP_TLV_MTU 0x0601 /* rfc 3988 */
static const struct tok ldp_tlv_values[] = {
{ LDP_TLV_FEC, "FEC" },
{ LDP_TLV_ADDRESS_LIST, "Address List" },
{ LDP_TLV_HOP_COUNT, "Hop Count" },
{ LDP_TLV_PATH_VECTOR, "Path Vector" },
{ LDP_TLV_GENERIC_LABEL, "Generic Label" },
{ LDP_TLV_ATM_LABEL, "ATM Label" },
{ LDP_TLV_FR_LABEL, "Frame-Relay Label" },
{ LDP_TLV_STATUS, "Status" },
{ LDP_TLV_EXTD_STATUS, "Extended Status" },
{ LDP_TLV_RETURNED_PDU, "Returned PDU" },
{ LDP_TLV_RETURNED_MSG, "Returned Message" },
{ LDP_TLV_COMMON_HELLO, "Common Hello Parameters" },
{ LDP_TLV_IPV4_TRANSPORT_ADDR, "IPv4 Transport Address" },
{ LDP_TLV_CONFIG_SEQ_NUMBER, "Configuration Sequence Number" },
{ LDP_TLV_IPV6_TRANSPORT_ADDR, "IPv6 Transport Address" },
{ LDP_TLV_COMMON_SESSION, "Common Session Parameters" },
{ LDP_TLV_ATM_SESSION_PARM, "ATM Session Parameters" },
{ LDP_TLV_FR_SESSION_PARM, "Frame-Relay Session Parameters" },
{ LDP_TLV_FT_SESSION, "Fault-Tolerant Session Parameters" },
{ LDP_TLV_LABEL_REQUEST_MSG_ID, "Label Request Message ID" },
{ LDP_TLV_MTU, "MTU" },
{ 0, NULL}
};
#define LDP_FEC_WILDCARD 0x01
#define LDP_FEC_PREFIX 0x02
#define LDP_FEC_HOSTADDRESS 0x03
/* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
#define LDP_FEC_MARTINI_VC 0x80
static const struct tok ldp_fec_values[] = {
{ LDP_FEC_WILDCARD, "Wildcard" },
{ LDP_FEC_PREFIX, "Prefix" },
{ LDP_FEC_HOSTADDRESS, "Host address" },
{ LDP_FEC_MARTINI_VC, "Martini VC" },
{ 0, NULL}
};
#define LDP_FEC_MARTINI_IFPARM_MTU 0x01
#define LDP_FEC_MARTINI_IFPARM_DESC 0x03
#define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
static const struct tok ldp_fec_martini_ifparm_values[] = {
{ LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
{ LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
{ LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
{ 0, NULL}
};
/* draft-ietf-pwe3-vccv-04.txt */
static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
{ 0x01, "PWE3 control word" },
{ 0x02, "MPLS Router Alert Label" },
{ 0x04, "MPLS inner label TTL = 1" },
{ 0, NULL}
};
/* draft-ietf-pwe3-vccv-04.txt */
static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
{ 0x01, "ICMP Ping" },
{ 0x02, "LSP Ping" },
{ 0x04, "BFD" },
{ 0, NULL}
};
static u_int ldp_pdu_print(netdissect_options *, const u_char *);
/*
* ldp tlv header
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |U|F| Type | Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* | Value |
* ~ ~
* | |
* | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
#define TLV_TCHECK(minlen) \
if (tlv_tlen < minlen) { \
ND_PRINT(" [tlv length %u < %u]", tlv_tlen, minlen); \
nd_print_invalid(ndo); \
goto invalid; \
}
static u_int
ldp_tlv_print(netdissect_options *ndo,
const u_char *tptr,
u_int msg_tlen)
{
struct ldp_tlv_header {
nd_uint16_t type;
nd_uint16_t length;
};
const struct ldp_tlv_header *ldp_tlv_header;
u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
u_char fec_type;
u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
char buf[100];
int i;
ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
ND_TCHECK_SIZE(ldp_tlv_header);
tlv_len=GET_BE_U_2(ldp_tlv_header->length);
if (tlv_len + 4U > msg_tlen) {
ND_PRINT("\n\t\t TLV contents go past end of message");
return 0;
}
tlv_tlen=tlv_len;
tlv_type=LDP_MASK_TLV_TYPE(GET_BE_U_2(ldp_tlv_header->type));
/* FIXME vendor private / experimental check */
ND_PRINT("\n\t %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
tok2str(ldp_tlv_values,
"Unknown",
tlv_type),
tlv_type,
tlv_len,
LDP_MASK_U_BIT(GET_BE_U_2(ldp_tlv_header->type)) ? "continue processing" : "ignore",
LDP_MASK_F_BIT(GET_BE_U_2(ldp_tlv_header->type)) ? "do" : "don't");
tptr+=sizeof(struct ldp_tlv_header);
switch(tlv_type) {
case LDP_TLV_COMMON_HELLO:
TLV_TCHECK(4);
ND_PRINT("\n\t Hold Time: %us, Flags: [%s Hello%s]",
GET_BE_U_2(tptr),
(GET_BE_U_2(tptr + 2)&0x8000) ? "Targeted" : "Link",
(GET_BE_U_2(tptr + 2)&0x4000) ? ", Request for targeted Hellos" : "");
break;
case LDP_TLV_IPV4_TRANSPORT_ADDR:
TLV_TCHECK(4);
ND_PRINT("\n\t IPv4 Transport Address: %s", GET_IPADDR_STRING(tptr));
break;
case LDP_TLV_IPV6_TRANSPORT_ADDR:
TLV_TCHECK(16);
ND_PRINT("\n\t IPv6 Transport Address: %s", GET_IP6ADDR_STRING(tptr));
break;
case LDP_TLV_CONFIG_SEQ_NUMBER:
TLV_TCHECK(4);
ND_PRINT("\n\t Sequence Number: %u", GET_BE_U_4(tptr));
break;
case LDP_TLV_ADDRESS_LIST:
TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
af = GET_BE_U_2(tptr);
tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
ND_PRINT("\n\t Address Family: %s, addresses",
tok2str(af_values, "Unknown (%u)", af));
switch (af) {
case AFNUM_INET:
while(tlv_tlen >= sizeof(nd_ipv4)) {
ND_TCHECK_LEN(tptr, sizeof(nd_ipv4));
ND_PRINT(" %s", GET_IPADDR_STRING(tptr));
tlv_tlen-=sizeof(nd_ipv4);
tptr+=sizeof(nd_ipv4);
}
break;
case AFNUM_INET6:
while(tlv_tlen >= sizeof(nd_ipv6)) {
ND_TCHECK_LEN(tptr, sizeof(nd_ipv6));
ND_PRINT(" %s", GET_IP6ADDR_STRING(tptr));
tlv_tlen-=sizeof(nd_ipv6);
tptr+=sizeof(nd_ipv6);
}
break;
default:
/* unknown AF */
break;
}
break;
case LDP_TLV_COMMON_SESSION:
TLV_TCHECK(8);
ND_PRINT("\n\t Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
GET_BE_U_2(tptr), GET_BE_U_2(tptr + 2),
(GET_BE_U_2(tptr + 6)&0x8000) ? "On Demand" : "Unsolicited",
(GET_BE_U_2(tptr + 6)&0x4000) ? "Enabled" : "Disabled"
);
break;
case LDP_TLV_FEC:
TLV_TCHECK(1);
fec_type = GET_U_1(tptr);
ND_PRINT("\n\t %s FEC (0x%02x)",
tok2str(ldp_fec_values, "Unknown", fec_type),
fec_type);
tptr+=1;
tlv_tlen-=1;
switch(fec_type) {
case LDP_FEC_WILDCARD:
break;
case LDP_FEC_PREFIX:
TLV_TCHECK(2);
af = GET_BE_U_2(tptr);
tptr+=2;
tlv_tlen-=2;
if (af == AFNUM_INET) {
i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
if (i == -2)
goto trunc;
if (i == -3)
ND_PRINT(": IPv4 prefix (goes past end of TLV)");
else if (i == -1)
ND_PRINT(": IPv4 prefix (invalid length)");
else
ND_PRINT(": IPv4 prefix %s", buf);
}
else if (af == AFNUM_INET6) {
i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
if (i == -2)
goto trunc;
if (i == -3)
ND_PRINT(": IPv4 prefix (goes past end of TLV)");
else if (i == -1)
ND_PRINT(": IPv6 prefix (invalid length)");
else
ND_PRINT(": IPv6 prefix %s", buf);
}
else
ND_PRINT(": Address family %u prefix", af);
break;
case LDP_FEC_HOSTADDRESS:
break;
case LDP_FEC_MARTINI_VC:
/*
* We assume the type was supposed to be one of the MPLS
* Pseudowire Types.
*/
TLV_TCHECK(7);
vc_info_len = GET_U_1(tptr + 2);
/*
* According to RFC 4908, the VC info Length field can be zero,
* in which case not only are there no interface parameters,
* there's no VC ID.
*/
if (vc_info_len == 0) {
ND_PRINT(": %s, %scontrol word, group-ID %u, VC-info-length: %u",
tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
GET_BE_U_4(tptr + 3),
vc_info_len);
break;
}
/* Make sure we have the VC ID as well */
TLV_TCHECK(11);
ND_PRINT(": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
GET_BE_U_4(tptr + 3),
GET_BE_U_4(tptr + 7),
vc_info_len);
if (vc_info_len < 4) {
/* minimum 4, for the VC ID */
ND_PRINT(" (invalid, < 4");
return(tlv_len+4); /* Type & Length fields not included */
}
vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
/* Skip past the fixed information and the VC ID */
tptr+=11;
tlv_tlen-=11;
TLV_TCHECK(vc_info_len);
while (vc_info_len > 2) {
vc_info_tlv_type = GET_U_1(tptr);
vc_info_tlv_len = GET_U_1(tptr + 1);
if (vc_info_tlv_len < 2)
break;
if (vc_info_len < vc_info_tlv_len)
break;
ND_PRINT("\n\t\tInterface Parameter: %s (0x%02x), len %u",
tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
vc_info_tlv_type,
vc_info_tlv_len);
switch(vc_info_tlv_type) {
case LDP_FEC_MARTINI_IFPARM_MTU:
ND_PRINT(": %u", GET_BE_U_2(tptr + 2));
break;
case LDP_FEC_MARTINI_IFPARM_DESC:
ND_PRINT(": ");
for (idx = 2; idx < vc_info_tlv_len; idx++)
fn_print_char(ndo, GET_U_1(tptr + idx));
break;
case LDP_FEC_MARTINI_IFPARM_VCCV:
ND_PRINT("\n\t\t Control Channels (0x%02x) = [%s]",
GET_U_1((tptr + 2)),
bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", GET_U_1((tptr + 2))));
ND_PRINT("\n\t\t CV Types (0x%02x) = [%s]",
GET_U_1((tptr + 3)),
bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", GET_U_1((tptr + 3))));
break;
default:
print_unknown_data(ndo, tptr+2, "\n\t\t ", vc_info_tlv_len-2);
break;
}
vc_info_len -= vc_info_tlv_len;
tptr += vc_info_tlv_len;
}
break;
}
break;
case LDP_TLV_GENERIC_LABEL:
TLV_TCHECK(4);
ND_PRINT("\n\t Label: %u", GET_BE_U_4(tptr) & 0xfffff);
break;
case LDP_TLV_STATUS:
TLV_TCHECK(8);
ui = GET_BE_U_4(tptr);
tptr+=4;
ND_PRINT("\n\t Status: 0x%02x, Flags: [%s and %s forward]",
ui&0x3fffffff,
ui&0x80000000 ? "Fatal error" : "Advisory Notification",
ui&0x40000000 ? "do" : "don't");
ui = GET_BE_U_4(tptr);
tptr+=4;
if (ui)
ND_PRINT(", causing Message ID: 0x%08x", ui);
break;
case LDP_TLV_FT_SESSION:
TLV_TCHECK(12);
ft_flags = GET_BE_U_2(tptr);
ND_PRINT("\n\t Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
ft_flags&0x8000 ? "" : "No ",
ft_flags&0x8 ? "" : "Don't ",
ft_flags&0x4 ? "" : "No ",
ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
ft_flags&0x1 ? "" : "Don't ");
/* 16 bits (FT Flags) + 16 bits (Reserved) */
tptr+=4;
ui = GET_BE_U_4(tptr);
if (ui)
ND_PRINT(", Reconnect Timeout: %ums", ui);
tptr+=4;
ui = GET_BE_U_4(tptr);
if (ui)
ND_PRINT(", Recovery Time: %ums", ui);
break;
case LDP_TLV_MTU:
TLV_TCHECK(2);
ND_PRINT("\n\t MTU: %u", GET_BE_U_2(tptr));
break;
/*
* FIXME those are the defined TLVs that lack a decoder
* you are welcome to contribute code ;-)
*/
case LDP_TLV_HOP_COUNT:
case LDP_TLV_PATH_VECTOR:
case LDP_TLV_ATM_LABEL:
case LDP_TLV_FR_LABEL:
case LDP_TLV_EXTD_STATUS:
case LDP_TLV_RETURNED_PDU:
case LDP_TLV_RETURNED_MSG:
case LDP_TLV_ATM_SESSION_PARM:
case LDP_TLV_FR_SESSION_PARM:
case LDP_TLV_LABEL_REQUEST_MSG_ID:
default:
if (ndo->ndo_vflag <= 1)
print_unknown_data(ndo, tptr, "\n\t ", tlv_tlen);
break;
}
return(tlv_len+4); /* Type & Length fields not included */
trunc:
nd_print_trunc(ndo);
return 0;
invalid:
return(tlv_len+4); /* Type & Length fields not included */
}
void
ldp_print(netdissect_options *ndo,
const u_char *pptr, u_int len)
{
u_int processed;
ndo->ndo_protocol = "ldp";
while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
processed = ldp_pdu_print(ndo, pptr);
if (processed == 0)
return;
if (len < processed) {
ND_PRINT(" [remaining length %u < %u]", len, processed);
nd_print_invalid(ndo);
break;
}
len -= processed;
pptr += processed;
}
}
static u_int
ldp_pdu_print(netdissect_options *ndo,
const u_char *pptr)
{
const struct ldp_common_header *ldp_com_header;
const struct ldp_msg_header *ldp_msg_header;
const u_char *tptr,*msg_tptr;
u_short tlen;
u_short pdu_len,msg_len,msg_type;
u_int msg_tlen;
int hexdump,processed;
ldp_com_header = (const struct ldp_common_header *)pptr;
ND_TCHECK_SIZE(ldp_com_header);
/*
* Sanity checking of the header.
*/
if (GET_BE_U_2(ldp_com_header->version) != LDP_VERSION) {
ND_PRINT("%sLDP version %u packet not supported",
(ndo->ndo_vflag < 1) ? "" : "\n\t",
GET_BE_U_2(ldp_com_header->version));
return 0;
}
pdu_len = GET_BE_U_2(ldp_com_header->pdu_length);
if (pdu_len < sizeof(struct ldp_common_header)-4) {
/* length too short */
ND_PRINT("%sLDP, pdu-length: %u (too short, < %u)",
(ndo->ndo_vflag < 1) ? "" : "\n\t",
pdu_len,
(u_int)(sizeof(struct ldp_common_header)-4));
return 0;
}
/* print the LSR-ID, label-space & length */
ND_PRINT("%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
(ndo->ndo_vflag < 1) ? "" : "\n\t",
GET_IPADDR_STRING(ldp_com_header->lsr_id),
GET_BE_U_2(ldp_com_header->label_space),
pdu_len);
/* bail out if non-verbose */
if (ndo->ndo_vflag < 1)
return 0;
/* ok they seem to want to know everything - lets fully decode it */
tptr = pptr + sizeof(struct ldp_common_header);
tlen = pdu_len - (sizeof(struct ldp_common_header)-4); /* Type & Length fields not included */
while(tlen>0) {
/* did we capture enough for fully decoding the msg header ? */
ND_TCHECK_LEN(tptr, sizeof(struct ldp_msg_header));
ldp_msg_header = (const struct ldp_msg_header *)tptr;
msg_len=GET_BE_U_2(ldp_msg_header->length);
msg_type=LDP_MASK_MSG_TYPE(GET_BE_U_2(ldp_msg_header->type));
if (msg_len < sizeof(struct ldp_msg_header)-4) {
/* length too short */
/* FIXME vendor private / experimental check */
ND_PRINT("\n\t %s Message (0x%04x), length: %u (too short, < %u)",
tok2str(ldp_msg_values,
"Unknown",
msg_type),
msg_type,
msg_len,
(u_int)(sizeof(struct ldp_msg_header)-4));
return 0;
}
/* FIXME vendor private / experimental check */
ND_PRINT("\n\t %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
tok2str(ldp_msg_values,
"Unknown",
msg_type),
msg_type,
msg_len,
GET_BE_U_4(ldp_msg_header->id),
LDP_MASK_U_BIT(GET_BE_U_2(ldp_msg_header->type)) ? "continue processing" : "ignore");
msg_tptr=tptr+sizeof(struct ldp_msg_header);
msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
/* did we capture enough for fully decoding the message ? */
ND_TCHECK_LEN(tptr, msg_len);
hexdump=FALSE;
switch(msg_type) {
case LDP_MSG_NOTIF:
case LDP_MSG_HELLO:
case LDP_MSG_INIT:
case LDP_MSG_KEEPALIVE:
case LDP_MSG_ADDRESS:
case LDP_MSG_LABEL_MAPPING:
case LDP_MSG_ADDRESS_WITHDRAW:
case LDP_MSG_LABEL_WITHDRAW:
while(msg_tlen >= 4) {
processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
if (processed == 0)
break;
msg_tlen-=processed;
msg_tptr+=processed;
}
break;
/*
* FIXME those are the defined messages that lack a decoder
* you are welcome to contribute code ;-)
*/
case LDP_MSG_LABEL_REQUEST:
case LDP_MSG_LABEL_RELEASE:
case LDP_MSG_LABEL_ABORT_REQUEST:
default:
if (ndo->ndo_vflag <= 1)
print_unknown_data(ndo, msg_tptr, "\n\t ", msg_tlen);
break;
}
/* do we want to see an additionally hexdump ? */
if (ndo->ndo_vflag > 1 || hexdump==TRUE)
print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t ",
msg_len);
tptr += msg_len+4;
tlen -= msg_len+4;
}
return pdu_len+4;
trunc:
nd_print_trunc(ndo);
return 0;
}
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