_l2tp.c

This directory contains source code for tcpdump, a tool for network monitoring and data acquisition

/*
 * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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, (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, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * L2TP support contributed by Motonori Shindo ([e-mail])
 */

#if 0
static const char rcsid[] = "@(#) $Header: /tcpdump/master/tcpdump/print-l2tp.c,v 1.6 1999/12/22 06:27:21 itojun Exp $";
#endif

#include <stdio.h>
#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "l2tp.h"
#include "interfac.h"

static char tstr[] = " [|l2tp]";

#ifndef TRUE
#define TRUE 1
#endif

#ifndef FALSE
#define FALSE 0
#endif

static char *l2tp_message_type_string[] = {
  "RESERVED_0",                 /* 0  Reserved */
  "SCCRQ",                      /* 1  Start-Control-Connection-Request */
  "SCCRP",                      /* 2  Start-Control-Connection-Reply */
  "SCCCN",                      /* 3  Start-Control-Connection-Connected */
  "StopCCN",                    /* 4  Stop-Control-Connection-Notification */
  "RESERVED_5",                 /* 5  Reserved */
  "HELLO",                      /* 6  Hello */
  "OCRQ",                       /* 7  Outgoing-Call-Request */
  "OCRP",                       /* 8  Outgoing-Call-Reply */
  "OCCN",                       /* 9  Outgoing-Call-Connected */
  "ICRQ",                       /* 10 Incoming-Call-Request */
  "ICRP",                       /* 11 Incoming-Call-Reply */
  "ICCN",                       /* 12 Incoming-Call-Connected */
  "RESERVED_13",                /* 13 Reserved */
  "CDN",                        /* 14 Call-Disconnect-Notify */
  "WEN",                        /* 15 WAN-Error-Notify */
  "SLI"                         /* 16 Set-Link-Info */
#define L2TP_MAX_MSGTYPE_INDEX  17
};

static void l2tp_msgtype_print (const u_char * dat, u_int length);
static void l2tp_result_code_print (const u_char * dat, u_int length);
static void l2tp_proto_ver_print (const u_char * dat, u_int length);
static void l2tp_framing_cap_print (const u_char * dat, u_int length);
static void l2tp_bearer_cap_print (const u_char * dat, u_int length);
static void l2tp_tie_breaker_print (const u_char * dat, u_int length);
static void l2tp_firm_ver_print (const u_char * dat, u_int length);
static void l2tp_host_name_print (const u_char * dat, u_int length);
static void l2tp_vendor_name_print (const u_char * dat, u_int length);
static void l2tp_assnd_tun_id_print (const u_char * dat, u_int length);
static void l2tp_recv_win_size_print (const u_char * dat, u_int length);
static void l2tp_challenge_print (const u_char * dat, u_int length);
static void l2tp_q931_cc_print (const u_char * dat, u_int length);
static void l2tp_challenge_resp_print (const u_char * dat, u_int length);
static void l2tp_assnd_sess_id_print (const u_char * dat, u_int length);
static void l2tp_call_ser_num_print (const u_char * dat, u_int length);
static void l2tp_minimum_bps_print (const u_char * dat, u_int length);
static void l2tp_maximum_bps_print (const u_char * dat, u_int length);
static void l2tp_bearer_type_print (const u_char * dat, u_int length);
static void l2tp_framing_type_print (const u_char * dat, u_int length);
static void l2tp_packet_proc_delay_print (const u_char * dat, u_int length);
static void l2tp_called_number_print (const u_char * dat, u_int length);
static void l2tp_calling_number_print (const u_char * dat, u_int length);
static void l2tp_sub_address_print (const u_char * dat, u_int length);
static void l2tp_tx_conn_speed_print (const u_char * dat, u_int length);
static void l2tp_phy_channel_id_print (const u_char * dat, u_int length);
static void l2tp_ini_recv_lcp_print (const u_char * dat, u_int length);
static void l2tp_last_sent_lcp_print (const u_char * dat, u_int length);
static void l2tp_last_recv_lcp_print (const u_char * dat, u_int length);
static void l2tp_proxy_auth_type_print (const u_char * dat, u_int length);
static void l2tp_proxy_auth_name_print (const u_char * dat, u_int length);
static void l2tp_proxy_auth_chal_print (const u_char * dat, u_int length);
static void l2tp_proxy_auth_id_print (const u_char * dat, u_int length);
static void l2tp_proxy_auth_resp_print (const u_char * dat, u_int length);
static void l2tp_call_errors_print (const u_char * dat, u_int length);
static void l2tp_accm_print (const u_char * dat, u_int length);
static void l2tp_random_vector_print (const u_char * dat, u_int length);
static void l2tp_private_grp_id_print (const u_char * dat, u_int length);
static void l2tp_rx_conn_speed_print (const u_char * dat, u_int length);
static void l2tp_seq_required_print (const u_char * dat, u_int length);
static void l2tp_ppp_discon_cc_print(const u_char *dat, u_int length);
static void l2tp_not_defined_print(const u_char *dat, u_int length);
static void l2tp_avp_print (const u_char * dat, u_int length);

/* XXX: need better way to handle discrete AVP numbers */
static struct l2tp_avp_vec l2tp_avp[] = {
{"MSGTYPE", l2tp_msgtype_print},                    /* 0  Message Type */
{"RESULT_CODE", l2tp_result_code_print},            /* 1  Result Code */
{"PROTO_VER", l2tp_proto_ver_print},                /* 2  Protocol Version */
{"FRAMING_CAP", l2tp_framing_cap_print},            /* 3  Framing Capabilities */
{"BEARER_CAP", l2tp_bearer_cap_print},              /* 4  Bearer Capabilities */
{"TIE_BREAKER", l2tp_tie_breaker_print},            /* 5  Tie Breaker */
{"FIRM_VER", l2tp_firm_ver_print},                  /* 6  Firmware Revision */
{"HOST_NAME", l2tp_host_name_print},                /* 7  Host Name */
{"VENDOR_NAME", l2tp_vendor_name_print},            /* 8  Vendor Name */
{"ASSND_TUN_ID", l2tp_assnd_tun_id_print},          /* 9  Assigned Tunnel ID */
{"RECV_WIN_SIZE", l2tp_recv_win_size_print},        /* 10 Receive Window Size */
{"CHALLENGE", l2tp_challenge_print},                /* 11 Challenge */
{"Q931_CC", l2tp_q931_cc_print},                    /* 12 Q.931 Cause Code */
{"CHALLENGE_RESP", l2tp_challenge_resp_print},      /* 13 Challenge Response */
{"ASSND_SESS_ID", l2tp_assnd_sess_id_print},        /* 14 Assigned Session ID */
{"CALL_SER_NUM", l2tp_call_ser_num_print},          /* 15 Call Serial Number */
{"MINIMUM_BPS", l2tp_minimum_bps_print},            /* 16 Minimum BPS */
{"MAXIMUM_BPS", l2tp_maximum_bps_print},            /* 17 Maximum BPS */
{"BEARER_TYPE", l2tp_bearer_type_print},            /* 18 Bearer Type */
{"FRAMING_TYPE", l2tp_framing_type_print},          /* 19 Framing Type */
{"PACKET_PROC_DELAY", l2tp_packet_proc_delay_print},/* 20 Packet Processing Delay (OBSOLETE) */
{"CALLED_NUMBER", l2tp_called_number_print},        /* 21 Called Number */
{"CALLING_NUMBER", l2tp_calling_number_print},      /* 22 Calling Number */
{"SUB_ADDRESS", l2tp_sub_address_print},            /* 23 Sub-Address */
{"TX_CONN_SPEED", l2tp_tx_conn_speed_print},        /* 24 (Tx) Connect Speed */
{"PHY_CHANNEL_ID", l2tp_phy_channel_id_print},      /* 25 Physical Channel ID */
{"INI_RECV_LCP", l2tp_ini_recv_lcp_print},          /* 26 Initial Received LCP CONFREQ */
{"LAST_SENT_LCP", l2tp_last_sent_lcp_print},        /* 27 Last Sent LCP CONFREQ */
{"LAST_RECV_LCP", l2tp_last_recv_lcp_print},        /* 28 Last Received LCP CONFREQ */
{"PROXY_AUTH_TYPE", l2tp_proxy_auth_type_print},    /* 29 Proxy Authen Type */
{"PROXY_AUTH_NAME", l2tp_proxy_auth_name_print},    /* 30 Proxy Authen Name */
{"PROXY_AUTH_CHAL", l2tp_proxy_auth_chal_print},    /* 31 Proxy Authen Challenge */
{"PROXY_AUTH_ID", l2tp_proxy_auth_id_print},        /* 32 Proxy Authen ID */
{"PROXY_AUTH_RESP", l2tp_proxy_auth_resp_print},    /* 33 Proxy Authen Response */
{"CALL_ERRORS", l2tp_call_errors_print},            /* 34 Call Errors */
{"ACCM", l2tp_accm_print},                          /* 35 ACCM */
{"RANDOM_VECTOR", l2tp_random_vector_print},        /* 36 Random Vector */
{"PRIVATE_GRP_ID", l2tp_private_grp_id_print},      /* 37 Private Group ID */
{"RX_CONN_SPEED", l2tp_rx_conn_speed_print},        /* 38 (Rx) Connect Speed */
{"SEQ_REQUIRED", l2tp_seq_required_print},          /* 39 Sequencing Required */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 40 Not Defined */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 41 Not Defined */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 42 Not Defined */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 43 Not Defined */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 44 Not Defined */
{"NOT_DEFINED", l2tp_not_defined_print},            /* 45 Not Defined */
{"PPP_DISCON_CC", l2tp_ppp_discon_cc_print},        /* 46 PPP Disconnect Cause Code */
#define L2TP_MAX_AVP_INDEX     47
};

#if 0
static char *l2tp_result_code_StopCCN[] = {
  "Reserved",
  "General request to clear control connection",
  "General error--Error Code indicates the problem",
  "Control channel already exists",
  "Requester is not authorized to establish a control channel",
  "The protocol version of the requester is not supported",
  "Requester is being shut down",
  "Finite State Machine error"
#define L2TP_MAX_RESULT_CODE_STOPCC_INDEX 8
};
#endif

#if 0
static char *l2tp_result_code_CDN[] = {
  "Reserved",
  "Call disconnected due to loss of carrier",
  "Call disconnected for the reason indicated in error code",
  "Call disconnected for administrative reasons",
  "Call failed due to lack of appropriate facilities being available (temporary condition)",
  "Call failed due to lack of appropriate facilities being available (permanent condition)",
  "Invalid destination",
  "Call failed due to no carrier detected",
  "Call failed due to detection of a busy signal",
  "Call failed due to lack of a dial tone",
  "Call was not established within time allotted by LAC",
  "Call was connected but no appropriate framing was detected"
#define L2TP_MAX_RESULT_CODE_CDN_INDEX  12
};
#endif

#if 0
static char *l2tp_error_code_general[] = {
  "No general error",
  "No control connection exists yet for this LAC-LNS pair",
  "Length is wrong",
  "One of the field values was out of range or " \
    "reserved field was non-zero" "Insufficient resources to handle this operation now",
  "The Session ID is invalid in this context",
  "A generic vendor-specific error occurred in the LAC",
  "Try another"
#define L2TP_MAX_ERROR_CODE_GENERAL_INDEX 8
};
#endif

/******************************/
/* generic print out routines */
/******************************/
static void print_string (const u_char * dat, u_int length)
{
  int i;
  for (i = 0; i < length; i++)
    PRINTF ("%c", *dat++);
}

static void print_octets (const u_char * dat, u_int length)
{
  int i;
  for (i = 0; i < length; i++)
    PRINTF ("%02x", *dat++);
}

static void print_short (const u_short * dat)
{
  PRINTF ("%u", ntohs (*dat));
}

static void print_int (const u_int * dat)
{
  PRINTF ("%lu", (u_long) ntohl (*dat));
}

/**********************************/
/* AVP-specific print out routines */
/**********************************/
static void l2tp_msgtype_print (const u_char * dat, u_int length)
{
  u_short *ptr = (u_short *) dat;

  if (ntohs (*ptr) < L2TP_MAX_MSGTYPE_INDEX)
    PRINTF ("%s", l2tp_message_type_string[ntohs (*ptr)]);
}

static void l2tp_result_code_print (const u_char * dat, u_int length)
{
  /* we just print out the result and error code number */
  u_short *ptr = (u_short *) dat;

  if (length == 2)       /* result code */
    PRINTF ("%u", ntohs (*ptr));

  else if (length == 4)  /* result & error code */
    PRINTF ("%u/%u", ntohs (*ptr), ntohs (*(ptr + 1)));

  else if (length > 4)   /* result & error code & msg */
  {
    PRINTF ("%u/%u ", ntohs (*ptr), ntohs (*(ptr + 1)));
    print_string ((u_char *) (ptr + 2), length - 4);
  }
}

static void l2tp_proto_ver_print (const u_char * dat, u_int length)
{
  PRINTF ("%d.%d", *dat, *(dat + 1));
}


static void l2tp_framing_cap_print (const u_char * dat, u_int length)
{
  u_int *ptr = (u_int *) dat;

  if (ntohl (*ptr) & L2TP_FRAMING_CAP_ASYNC_MASK)
    PUTCHAR ('A');

  if (ntohl (*ptr) & L2TP_FRAMING_CAP_SYNC_MASK)
    PUTCHAR ('S');
}

static void l2tp_bearer_cap_print (const u_char * dat, u_int length)
{
  u_int *ptr = (u_int *) dat;

  if (ntohl (*ptr) & L2TP_BEARER_CAP_ANALOG_MASK)
    PUTCHAR ('A');

  if (ntohl (*ptr) & L2TP_BEARER_CAP_DIGITAL_MASK)
    PUTCHAR ('D');
}

static void l2tp_tie_breaker_print (const u_char * dat, u_int length)
{
  PRINTF ("%lx", *(u_long *) dat);  /* XXX */
}

static void l2tp_firm_ver_print (const u_char * dat, u_int length)
{
  print_short ((u_short *) dat);
}

static void l2tp_host_name_print (const u_char * dat, u_int length)
{
  print_string (dat, length);
}

static void l2tp_vendor_name_print (const u_char * dat, u_int length)
{
  print_string (dat, length);
}

static void l2tp_assnd_tun_id_print (const u_char * dat, u_int length)
{
  print_short ((u_short *) dat);
}

static void l2tp_recv_win_size_print (const u_char * dat, u_int length)
{
  print_short ((u_short *) dat);
}

static void l2tp_challenge_print (const u_char * dat, u_int length)
{
  print_octets (dat, length);
}

static void l2tp_q931_cc_print (const u_char * dat, u_int length)
{
  print_short ((u_short *) dat);
  PRINTF (", %02x", dat[2]);
  if (length > 3)
  {
    PUTCHAR (' ');
    print_string (dat + 3, length - 3);
  }
}

static void l2tp_challenge_resp_print (const u_char * dat, u_int length)
{
  print_octets (dat, 16);       /* XXX length should be 16? */
}

static void l2tp_assnd_sess_id_print (const u_char * dat, u_int length)
{
  print_short ((u_short *) dat);
}

static void l2tp_call_ser_num_print (const u_char * dat, u_int length)