/*
* 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@juniper.net)
*/
#define NETDISSECT_REWORKED
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include "interface.h"
#include "extract.h"
#include "udp.h"
/*
* Control packet, BFDv0, draft-katz-ward-bfd-01.txt
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |Vers | Diag |H|D|P|F| Rsvd | Detect Mult | Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | My Discriminator |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Your Discriminator |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Desired Min TX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Required Min RX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Required Min Echo RX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
/*
* Control packet, BFDv1, draft-ietf-bfd-base-02.txt
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |Vers | Diag |Sta|P|F|C|A|D|R| Detect Mult | Length |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | My Discriminator |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Your Discriminator |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Desired Min TX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Required Min RX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Required Min Echo RX Interval |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
struct bfd_header_t {
uint8_t version_diag;
uint8_t flags;
uint8_t detect_time_multiplier;
uint8_t length;
uint8_t my_discriminator[4];
uint8_t your_discriminator[4];
uint8_t desired_min_tx_interval[4];
uint8_t required_min_rx_interval[4];
uint8_t required_min_echo_interval[4];
};
/*
* An optional Authentication Header may be present
*
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | Auth Type | Auth Len | Authentication Data... |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
struct bfd_auth_header_t {
uint8_t auth_type;
uint8_t auth_len;
uint8_t auth_data;
};
static const struct tok bfd_v1_authentication_values[] = {
{ 0, "Reserved" },
{ 1, "Simple Password" },
{ 2, "Keyed MD5" },
{ 3, "Meticulous Keyed MD5" },
{ 4, "Keyed SHA1" },
{ 5, "Meticulous Keyed SHA1" },
{ 0, NULL }
};
#define BFD_EXTRACT_VERSION(x) (((x)&0xe0)>>5)
#define BFD_EXTRACT_DIAG(x) ((x)&0x1f)
static const struct tok bfd_port_values[] = {
{ BFD_CONTROL_PORT, "Control" },
{ BFD_ECHO_PORT, "Echo" },
{ 0, NULL }
};
static const struct tok bfd_diag_values[] = {
{ 0, "No Diagnostic" },
{ 1, "Control Detection Time Expired" },
{ 2, "Echo Function Failed" },
{ 3, "Neighbor Signaled Session Down" },
{ 4, "Forwarding Plane Reset" },
{ 5, "Path Down" },
{ 6, "Concatenated Path Down" },
{ 7, "Administratively Down" },
{ 8, "Reverse Concatenated Path Down" },
{ 0, NULL }
};
static const struct tok bfd_v0_flag_values[] = {
{ 0x80, "I Hear You" },
{ 0x40, "Demand" },
{ 0x20, "Poll" },
{ 0x10, "Final" },
{ 0x08, "Reserved" },
{ 0x04, "Reserved" },
{ 0x02, "Reserved" },
{ 0x01, "Reserved" },
{ 0, NULL }
};
#define BFD_FLAG_AUTH 0x04
static const struct tok bfd_v1_flag_values[] = {
{ 0x20, "Poll" },
{ 0x10, "Final" },
{ 0x08, "Control Plane Independent" },
{ BFD_FLAG_AUTH, "Authentication Present" },
{ 0x02, "Demand" },
{ 0x01, "Reserved" },
{ 0, NULL }
};
static const struct tok bfd_v1_state_values[] = {
{ 0, "AdminDown" },
{ 1, "Down" },
{ 2, "Init" },
{ 3, "Up" },
{ 0, NULL }
};
void
bfd_print(netdissect_options *ndo, register const u_char *pptr,
register u_int len, register u_int port)
{
const struct bfd_header_t *bfd_header;
const struct bfd_auth_header_t *bfd_auth_header;
uint8_t version = 0;
bfd_header = (const struct bfd_header_t *)pptr;
if (port == BFD_CONTROL_PORT) {
ND_TCHECK(*bfd_header);
version = BFD_EXTRACT_VERSION(bfd_header->version_diag);
} else if (port == BFD_ECHO_PORT) {
/* Echo is BFD v1 only */
version = 1;
}
switch ((port << 8) | version) {
/* BFDv0 */
case (BFD_CONTROL_PORT << 8):
if (ndo->ndo_vflag < 1)
{
ND_PRINT((ndo, "BFDv%u, %s, Flags: [%s], length: %u",
version,
tok2str(bfd_port_values, "unknown (%u)", port),
bittok2str(bfd_v0_flag_values, "none", bfd_header->flags),
len));
return;
}
ND_PRINT((ndo, "BFDv%u, length: %u\n\t%s, Flags: [%s], Diagnostic: %s (0x%02x)",
version,
len,
tok2str(bfd_port_values, "unknown (%u)", port),
bittok2str(bfd_v0_flag_values, "none", bfd_header->flags),
tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(bfd_header->version_diag)),
BFD_EXTRACT_DIAG(bfd_header->version_diag)));
ND_PRINT((ndo, "\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u",
bfd_header->detect_time_multiplier,
bfd_header->detect_time_multiplier * EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000,
bfd_header->length));
ND_PRINT((ndo, "\n\tMy Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->my_discriminator)));
ND_PRINT((ndo, ", Your Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->your_discriminator)));
ND_PRINT((ndo, "\n\t Desired min Tx Interval: %4u ms", EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000));
ND_PRINT((ndo, "\n\t Required min Rx Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_rx_interval)/1000));
ND_PRINT((ndo, "\n\t Required min Echo Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_echo_interval)/1000));
break;
/* BFDv1 */
case (BFD_CONTROL_PORT << 8 | 1):
if (ndo->ndo_vflag < 1)
{
ND_PRINT((ndo, "BFDv%u, %s, State %s, Flags: [%s], length: %u",
version,
tok2str(bfd_port_values, "unknown (%u)", port),
tok2str(bfd_v1_state_values, "unknown (%u)", (bfd_header->flags & 0xc0) >> 6),
bittok2str(bfd_v1_flag_values, "none", bfd_header->flags & 0x3f),
len));
return;
}
ND_PRINT((ndo, "BFDv%u, length: %u\n\t%s, State %s, Flags: [%s], Diagnostic: %s (0x%02x)",
version,
len,
tok2str(bfd_port_values, "unknown (%u)", port),
tok2str(bfd_v1_state_values, "unknown (%u)", (bfd_header->flags & 0xc0) >> 6),
bittok2str(bfd_v1_flag_values, "none", bfd_header->flags & 0x3f),
tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(bfd_header->version_diag)),
BFD_EXTRACT_DIAG(bfd_header->version_diag)));
ND_PRINT((ndo, "\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u",
bfd_header->detect_time_multiplier,
bfd_header->detect_time_multiplier * EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000,
bfd_header->length));
ND_PRINT((ndo, "\n\tMy Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->my_discriminator)));
ND_PRINT((ndo, ", Your Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->your_discriminator)));
ND_PRINT((ndo, "\n\t Desired min Tx Interval: %4u ms", EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000));
ND_PRINT((ndo, "\n\t Required min Rx Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_rx_interval)/1000));
ND_PRINT((ndo, "\n\t Required min Echo Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_echo_interval)/1000));
if (bfd_header->flags & BFD_FLAG_AUTH) {
pptr += sizeof (const struct bfd_header_t);
bfd_auth_header = (const struct bfd_auth_header_t *)pptr;
ND_TCHECK2(*bfd_auth_header, sizeof(const struct bfd_auth_header_t));
ND_PRINT((ndo, "\n\t%s (%u) Authentication, length %u present",
tok2str(bfd_v1_authentication_values,"Unknown",bfd_auth_header->auth_type),
bfd_auth_header->auth_type,
bfd_auth_header->auth_len));
}
break;
/* BFDv0 */
case (BFD_ECHO_PORT << 8): /* not yet supported - fall through */
/* BFDv1 */
case (BFD_ECHO_PORT << 8 | 1):
default:
ND_PRINT((ndo, "BFD, %s, length: %u",
tok2str(bfd_port_values, "unknown (%u)", port),
len));
if (ndo->ndo_vflag >= 1) {
if(!print_unknown_data(ndo, pptr,"\n\t",len))
return;
}
break;
}
return;
trunc:
ND_PRINT((ndo, "[|BFD]"));
}
/*
* Local Variables:
* c-style: whitesmith
* c-basic-offset: 8
* End:
*/