print-cfm.c

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/*
 * Copyright (c) 1998-2006 The TCPDUMP project
 *
 * 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.
 *
 * Support for the IEEE Connectivity Fault Management Protocols as per 802.1ag.
 *
 * Original code by Hannes Gredler ([e-mail])
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/tcpdump/print-cfm.c,v 1.5 2007-07-24 16:01:42 hannes Exp $";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <tcpdump-stdinc.h>

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

#include "interface.h"
#include "extract.h"
#include "ether.h"
#include "addrtoname.h"
#include "oui.h"
#include "af.h"

/*
 * Prototypes
 */
const char * cfm_egress_id_string(register const u_char *);
int cfm_mgmt_addr_print(register const u_char *);

struct cfm_common_header_t {
    u_int8_t mdlevel_version;
    u_int8_t opcode;
    u_int8_t flags;
    u_int8_t first_tlv_offset;
};

#define	CFM_VERSION 0
#define CFM_EXTRACT_VERSION(x) (((x)&0x1f))
#define CFM_EXTRACT_MD_LEVEL(x) (((x)&0xe0)>>5)

#define	CFM_OPCODE_CCM 1
#define	CFM_OPCODE_LBR 2
#define	CFM_OPCODE_LBM 3
#define	CFM_OPCODE_LTR 4
#define	CFM_OPCODE_LTM 5

static const struct tok cfm_opcode_values[] = {
    { CFM_OPCODE_CCM, "Continouity Check Message"},
    { CFM_OPCODE_LBR, "Loopback Reply"},
    { CFM_OPCODE_LBM, "Loopback Message"},
    { CFM_OPCODE_LTR, "Linktrace Reply"},
    { CFM_OPCODE_LTM, "Linktrace Message"},
    { 0, NULL}
};

/*
 * Message Formats.
 */
struct cfm_ccm_t {
    u_int8_t sequence[4];
    u_int8_t ma_epi[2];
    u_int8_t md_nameformat;
    u_int8_t md_namelength;
    u_int8_t md_name[46]; /* md name and short ma name */
    u_int8_t reserved_itu[16];
    u_int8_t reserved[6];
};

/*
 * Timer Bases for the CCM Interval field.
 * Expressed in units of seconds.
 */
const float ccm_interval_base[8] = {0, 0.003333, 0.01, 0.1, 1, 10, 60, 600};
#define CCM_INTERVAL_MIN_MULTIPLIER 3.25
#define CCM_INTERVAL_MAX_MULTIPLIER 3.5

#define CFM_CCM_RDI_FLAG 0x80
#define CFM_EXTRACT_CCM_INTERVAL(x) (((x)&0x07))

#define CFM_CCM_MD_FORMAT_8021 0
#define CFM_CCM_MD_FORMAT_NONE 1
#define CFM_CCM_MD_FORMAT_DNS  2
#define CFM_CCM_MD_FORMAT_MAC  3
#define CFM_CCM_MD_FORMAT_CHAR 4

static const struct tok cfm_md_nameformat_values[] = {
    { CFM_CCM_MD_FORMAT_8021, "IEEE 802.1"},
    { CFM_CCM_MD_FORMAT_NONE, "No MD Name present"},
    { CFM_CCM_MD_FORMAT_DNS, "DNS string"},
    { CFM_CCM_MD_FORMAT_MAC, "MAC + 16Bit Integer"},
    { CFM_CCM_MD_FORMAT_CHAR, "Character string"},
    { 0, NULL}
};

#define CFM_CCM_MA_FORMAT_8021 0
#define CFM_CCM_MA_FORMAT_VID  1
#define CFM_CCM_MA_FORMAT_CHAR 2
#define CFM_CCM_MA_FORMAT_INT  3
#define CFM_CCM_MA_FORMAT_VPN  4

static const struct tok cfm_ma_nameformat_values[] = {
    { CFM_CCM_MA_FORMAT_8021, "IEEE 802.1"},
    { CFM_CCM_MA_FORMAT_VID, "Primary VID"},
    { CFM_CCM_MA_FORMAT_CHAR, "Character string"},
    { CFM_CCM_MA_FORMAT_INT, "16Bit Integer"},
    { CFM_CCM_MA_FORMAT_VPN, "RFC2685 VPN-ID"},
    { 0, NULL}
};

struct cfm_lbm_t {
    u_int8_t transaction_id[4];
    u_int8_t reserved[4];
};

struct cfm_ltm_t {
    u_int8_t transaction_id[4];
    u_int8_t egress_id[8];
    u_int8_t ttl;
    u_int8_t original_mac[ETHER_ADDR_LEN];
    u_int8_t target_mac[ETHER_ADDR_LEN];
    u_int8_t reserved[3];
};

static const struct tok cfm_ltm_flag_values[] = {
    { 0x80, "Use Forwarding-DB only"},
    { 0, NULL}
};

struct cfm_ltr_t {
    u_int8_t transaction_id[4];
    u_int8_t last_egress_id[8];
    u_int8_t next_egress_id[8];
    u_int8_t ttl;
    u_int8_t replay_action;
    u_int8_t reserved[6];
};

static const struct tok cfm_ltr_flag_values[] = {
    { 0x80, "Forwarded"},
    { 0x40, "Terminal MEP"},
    { 0, NULL}
};

static const struct tok cfm_ltr_replay_action_values[] = {
    { 1, "Exact Match"},
    { 2, "Filtering DB"},
    { 3, "MIP CCM DB"},
    { 0, NULL}
};


#define CFM_TLV_END 0
#define CFM_TLV_SENDER_ID 1
#define CFM_TLV_PORT_STATUS 2
#define CFM_TLV_INTERFACE_STATUS 3
#define CFM_TLV_DATA 4
#define CFM_TLV_REPLY_INGRESS 5
#define CFM_TLV_REPLY_EGRESS 6
#define CFM_TLV_PRIVATE 31

static const struct tok cfm_tlv_values[] = {
    { CFM_TLV_END, "End"},
    { CFM_TLV_SENDER_ID, "Sender ID"},
    { CFM_TLV_PORT_STATUS, "Port status"},
    { CFM_TLV_INTERFACE_STATUS, "Interface status"},
    { CFM_TLV_DATA, "Data"},
    { CFM_TLV_REPLY_INGRESS, "Reply Ingress"},
    { CFM_TLV_REPLY_EGRESS, "Reply Egress"},
    { CFM_TLV_PRIVATE, "Organization Specific"},
    { 0, NULL}
};

/*
 * TLVs
 */

struct cfm_tlv_header_t {
    u_int8_t type;
    u_int8_t length[2];
};

/* FIXME define TLV formats */

static const struct tok cfm_tlv_port_status_values[] = {
    { 1, "Blocked"},
    { 2, "Up"},
    { 0, NULL}
};

static const struct tok cfm_tlv_interface_status_values[] = {
    { 1, "Up"},
    { 2, "Down"},
    { 3, "Testing"},
    { 5, "Dormant"},
    { 6, "not present"},
    { 7, "lower Layer down"},
    { 0, NULL}
};

#define CFM_CHASSIS_ID_CHASSIS_COMPONENT 1
#define CFM_CHASSIS_ID_INTERFACE_ALIAS 2
#define CFM_CHASSIS_ID_PORT_COMPONENT 3
#define CFM_CHASSIS_ID_MAC_ADDRESS 4
#define CFM_CHASSIS_ID_NETWORK_ADDRESS 5
#define CFM_CHASSIS_ID_INTERFACE_NAME 6
#define CFM_CHASSIS_ID_LOCAL 7

static const struct tok cfm_tlv_senderid_chassisid_values[] = {
    { 0, "Reserved"},
    { CFM_CHASSIS_ID_CHASSIS_COMPONENT, "Chassis component"},
    { CFM_CHASSIS_ID_INTERFACE_ALIAS, "Interface alias"},
    { CFM_CHASSIS_ID_PORT_COMPONENT, "Port component"},
    { CFM_CHASSIS_ID_MAC_ADDRESS, "MAC address"},
    { CFM_CHASSIS_ID_NETWORK_ADDRESS, "Network address"},
    { CFM_CHASSIS_ID_INTERFACE_NAME, "Interface name"},
    { CFM_CHASSIS_ID_LOCAL, "Locally assigned"},
    { 0, NULL}
};


int
cfm_mgmt_addr_print(register const u_char *tptr) {

    u_int mgmt_addr_type;
    u_int hexdump =  FALSE;

    /*
     * Altough AFIs are tpically 2 octects wide,
     * 802.1ab specifies that this field width
     * is only once octet
     */
    mgmt_addr_type = *tptr;
    printf("\n\t  Management Address Type %s (%u)",
           tok2str(af_values, "Unknown", mgmt_addr_type),
           mgmt_addr_type);

    /*
     * Resolve the passed in Address.
     */
    switch(mgmt_addr_type) {
    case AFNUM_INET:
        printf(", %s", ipaddr_string(tptr + 1));
        break;

#ifdef INET6
    case AFNUM_INET6:
        printf(", %s", ip6addr_string(tptr + 1));
        break;
#endif

    default:
        hexdump = TRUE;
        break;
    }

    return hexdump;
}

/*
 * The egress-ID string is a 16-Bit string plus a MAC address.
 */
const char *
cfm_egress_id_string(register const u_char *tptr) {
    static char egress_id_buffer[80];
    
    snprintf(egress_id_buffer, sizeof(egress_id_buffer),
             "MAC %0x4x-%s",
             EXTRACT_16BITS(tptr),
             etheraddr_string(tptr+2));

    return egress_id_buffer;
}

void
cfm_print(register const u_char *pptr, register u_int length) {

    const struct cfm_common_header_t *cfm_common_header;
    const struct cfm_tlv_header_t *cfm_tlv_header;
    const u_int8_t *tptr, *tlv_ptr, *ma_name, *ma_nameformat, *ma_namelength;
    u_int hexdump, tlen, cfm_tlv_len, cfm_tlv_type, ccm_interval;


    union {
        const struct cfm_ccm_t *cfm_ccm;
        const struct cfm_lbm_t *cfm_lbm;
        const struct cfm_ltm_t *cfm_ltm;
        const struct cfm_ltr_t *cfm_ltr;
    } msg_ptr;

    tptr=pptr;
    cfm_common_header = (const struct cfm_common_header_t *)pptr;
    TCHECK(*cfm_common_header);

    /*
     * Sanity checking of the header.
     */
    if (CFM_EXTRACT_VERSION(cfm_common_header->mdlevel_version) != CFM_VERSION) {
	printf("CFMv%u not supported, length %u",
               CFM_EXTRACT_VERSION(cfm_common_header->mdlevel_version), length);
	return;
    }

    printf("CFMv%u %s, MD Level %u, length %u",