/*===================================================================

  Copyright (c) 1996
  Hewlett-Packard Company

  ATTENTION: USE OF THIS SOFTWARE IS SUBJECT TO THE FOLLOWING TERMS.
  Permission to use, copy, modify, distribute and/or sell this software 
  and/or its documentation is hereby granted without fee. User agrees 
  to display the above copyright notice and this license notice in all 
  copies of the software and any documentation of the software. User 
  agrees to assume all liability for the use of the software; Hewlett-Packard 
  makes no representations about the suitability of this software for any 
  purpose. It is provided "AS-IS without warranty of any kind,either express 
  or implied. User hereby grants a royalty-free license to any and all 
  derivatives based upon this software code base. 


  SNMP++ S N M P M E S S A G E . C P P   
      
  SNMPMESSAGE CLASS DEFINITION
       
  VERSION:
  2.6
  
  RCS INFO:
  $Header: /caimis/cvs/cflowd/snmp++/classes/src/snmpmsg.cpp,v 1.4 2000/04/07 04:47:50 dwm Exp $
       
  DESIGN:
  Peter E Mellquist
                
  AUTHOR:      
  Peter E Mellquist
              
  LANGUAGE:
  ANSI C++ 
      
  OPERATING SYSTEMS:
  Win 32
  BSD UNIX
      
  DESCRIPTION:
  ASN.1	encoding / decoding class
      		 
=====================================================================*/ 

#include "snmpmsg.h"	                // header file for SnmpMessage
#include "asn1.h"                       // ASN.1 header file
#include "stdio.h"                      // standard io file 


#ifndef INADDR_NONE
  #define INADDR_NONE 0xFFFFFFFF
#endif

//--------------[ well known trap ids ]-----------------------------------
// SMI trap oid def
class snmpTrapsOid: public Oid {
public: 
  snmpTrapsOid (void)
      : Oid("1.3.6.1.6.3.1.1.5") { };
}; 

// SMI Enterprise Oid
class snmpTrapEnterpriseOid: public Oid {
public: 
  snmpTrapEnterpriseOid(void)
      : Oid("1.3.6.1.6.3.1.1.4.3.0") { };
}; 

// SMI Cold Start Oid
class coldStartOid: public snmpTrapsOid {
public: 
  coldStartOid( void)
  {
    *this+=".1";
  };
};

// SMI WarmStart Oid
class warmStartOid: public snmpTrapsOid {
public: 
  warmStartOid( void)
  {
    *this+=".2";
  };
};

// SMI LinkDown Oid
class linkDownOid: public snmpTrapsOid {
public: 
  linkDownOid( void)
  {
    *this+=".3";
  };
}; 


// SMI LinkUp Oid
class linkUpOid: public snmpTrapsOid {
public: 
  linkUpOid( void)
  {
    *this+=".4";
  };
};

// SMI Authentication Failure Oid
class authenticationFailureOid: public snmpTrapsOid {
public: 
  authenticationFailureOid( void)
  {
    *this+=".5";
  };
}; 

// SMI egpneighborloss Oid
class egpNeighborLossOid: public snmpTrapsOid {
public: 
  egpNeighborLossOid( void)
  {
    *this+=".6";
  };
};

const coldStartOid coldStart;
const warmStartOid warmStart;
const linkDownOid linkDown;
const linkUpOid linkUp;
const authenticationFailureOid authenticationFailure;
const egpNeighborLossOid egpNeighborLoss;
const snmpTrapEnterpriseOid snmpTrapEnterprise;

//------------[ convert SNMP++ VB to WinSNMP smiVALUE ]----------------
int convertVbToSmival( Vb &tempvb, SmiVALUE *smival )
{
  smival->syntax = tempvb.get_syntax();
  switch ( smival->syntax ) {
    
    // case sNMP_SYNTAX_NULL
    case sNMP_SYNTAX_NULL:
    case sNMP_SYNTAX_NOSUCHOBJECT:
    case sNMP_SYNTAX_NOSUCHINSTANCE:
    case sNMP_SYNTAX_ENDOFMIBVIEW:
      break;
      
      // case sNMP_SYNTAX_INT32:
    case sNMP_SYNTAX_INT:
      tempvb.get_value(smival->value.sNumber);
      break;
      
      //    case sNMP_SYNTAX_UINT32:
    case sNMP_SYNTAX_GAUGE32:
    case sNMP_SYNTAX_CNTR32:
    case sNMP_SYNTAX_TIMETICKS:
    case sNMP_SYNTAX_UINT32:
      tempvb.get_value(smival->value.uNumber);
      break;
      
      // case Counter64
    case sNMP_SYNTAX_CNTR64:
      {
        Counter64 c64;
        tempvb.get_value(c64);
        smival->value.hNumber.hipart = c64.high();
        smival->value.hNumber.lopart = c64.low();
      }
    break;
    
    case sNMP_SYNTAX_BITS:
    case sNMP_SYNTAX_OCTETS:
    case sNMP_SYNTAX_IPADDR:
      {
        OctetStr os;
        tempvb.get_value(os);
        smival->value.string.ptr = NULL;
        smival->value.string.len = os.len();
        if ( smival->value.string.len > 0 ) 
        {
          smival->value.string.ptr =
            (SmiLPBYTE) new  unsigned char [smival->value.string.len];
          if ( smival->value.string.ptr ) 
          {
            for (int i=0; i<(int) smival->value.string.len ; i++)
              smival->value.string.ptr[i] = os[i];
          } 
          else 
          { 
            smival->syntax = sNMP_SYNTAX_NULL;  // invalidate the smival
            return SNMP_CLASS_RESOURCE_UNAVAIL;
          }
        }
      }
    break;
    
    case sNMP_SYNTAX_OID:
      {
        Oid oid;
        tempvb.get_value(oid);
        smival->value.oid.ptr = NULL;
        smival->value.oid.len = oid.len();
        if ( smival->value.oid.len > 0 ) 
        {
          smival->value.oid.ptr =
            (SmiLPUINT32) new unsigned long [ smival->value.oid.len];
          if ( smival->value.oid.ptr ) 
          {
            for (int i=0; i<(int)smival->value.oid.len ; i++)
              smival->value.oid.ptr[i] = oid[i];
          } 
          else 
          {
            smival->syntax = sNMP_SYNTAX_NULL;  // invalidate the smival
            return SNMP_CLASS_RESOURCE_UNAVAIL;
          }
        }
      }
    break;
    
    default:
      return SNMP_CLASS_INTERNAL_ERROR;
  }
  return SNMP_CLASS_SUCCESS;
};

// free a SMI value
void freeSmivalDescriptor( SmiVALUE *smival )
{
  switch ( smival->syntax ) {
    case sNMP_SYNTAX_OCTETS:
    case sNMP_SYNTAX_OPAQUE:
    case sNMP_SYNTAX_IPADDR:
    case sNMP_SYNTAX_BITS:		    // obsoleted in SNMPv2 Draft Std
      delete [] smival->value.string.ptr;	   
      break;
      
    case sNMP_SYNTAX_OID:
      delete [] smival->value.oid.ptr;
      break;
  }
  smival->syntax = sNMP_SYNTAX_NULL;
};


// load up a SnmpMessage
int SnmpMessage::load( Pdu pdu,                      // Pdu object to load
                       OctetStr community,           // community to use
                       snmp_version version)         // version 1 or 2
{
  int status;
  
  // create a raw pdu
  snmp_pdu *raw_pdu;
  raw_pdu = snmp_pdu_create( (int) pdu.get_type());
  
  Oid enterprise;
  
  // make sure pdu is valid
  if ( !pdu.valid()) 
    return SNMP_CLASS_INVALID_PDU;
  
  // load it up
  raw_pdu->reqid = pdu.get_request_id();
  raw_pdu->errstat= (unsigned long) pdu.get_error_status();
  raw_pdu->errindex= (unsigned long) pdu.get_error_index();
  
  // if its a V1 trap then load up other values
  // for v2, use normal pdu format
  if ( raw_pdu->command == sNMP_PDU_V1TRAP)
  {
    // forget about the v1 trap agent address
    // use transport address to determine where
    // it came from
    
    // DON'T forget about the v1 trap agent address (changed by Frank Fock)
    char addrString[256];

    if (gethostname(addrString, 255) == 0) {
      IpAddress my_address;
      hostent *lookupResult;
      in_addr ipAddr;

      if ((ipAddr.s_addr = inet_addr(addrString)) == INADDR_NONE){
        lookupResult = gethostbyname(addrString);
        if (lookupResult) {
          if (lookupResult->h_length == sizeof(in_addr)){
            memcpy((void *) &ipAddr, (void *) lookupResult->h_addr_list[0],
                   sizeof(in_addr));
            my_address = inet_ntoa(ipAddr);
          }
        }
      }
      else
        my_address = addrString;

      struct sockaddr_in agent_addr;   // agent address socket struct

      // prepare the agent address
      memset(&agent_addr, 0, sizeof(agent_addr));
      agent_addr.sin_family = AF_INET;
      agent_addr.sin_addr.s_addr =
        inet_addr(((IpAddress &)my_address).IpAddress::get_printable());
      raw_pdu->agent_addr = agent_addr;
    }
    
    //-----[ compute generic trap value ]-------------------------------
    // determine the generic value
    // 0 - cold start
    // 1 - warm start
    // 2 - link down
    // 3 - link up
    // 4 - authentication failure
    // 5 - egpneighborloss
    // 6 - enterprise specific
    Oid trapid;
    pdu.get_notify_id( trapid);
    if ( !trapid.valid() || trapid.len() < 2 ) 
    {
      snmp_free_pdu( raw_pdu);
      return SNMP_CLASS_INVALID_NOTIFYID;
    }
    raw_pdu->specific_type=0;
    if ( trapid == coldStart)
      raw_pdu->trap_type = 0;  // cold start
    else if ( trapid == warmStart)
      raw_pdu->trap_type = 1;  // warm start
    else if( trapid == linkDown)
      raw_pdu->trap_type = 2;  // link down
    else if ( trapid == linkUp)
      raw_pdu->trap_type = 3;  // link up
    else if ( trapid == authenticationFailure )
      raw_pdu->trap_type = 4;  // authentication failure
    else if ( trapid == egpNeighborLoss)
      raw_pdu->trap_type = 5;  // egp neighbor loss
    else {
      raw_pdu->trap_type = 6;     // enterprise specific
      // last oid subid is the specific value
      // if 2nd to last subid is "0", remove it 
      // enterprise is always the notify oid prefix
      raw_pdu->specific_type = (int) trapid[(int) (trapid.len()-1)]; 
      trapid.trim(1);
      if ( trapid[(int)(trapid.len()-1)] == 0 )
        trapid.trim(1);
      enterprise = trapid;      
    }
    
    if ( raw_pdu->trap_type !=6)
      pdu.get_notify_enterprise( enterprise);
    if ( enterprise.len() >0) {
      // note!!
      // these are hooks into an SNMP++ oid
      // and therefor the raw_pdu enterprise
      // should not free them. null them out!!
      SmiLPOID rawOid;
      rawOid = enterprise.oidval();
      raw_pdu->enterprise = rawOid->ptr;
      raw_pdu->enterprise_length = (int) rawOid->len;
    }
    
    // timestamp
    TimeTicks timestamp;
    pdu.get_notify_timestamp( timestamp);
    raw_pdu->time = ( unsigned long) timestamp;
    
  }
  
  // if its a v2 trap then we need to make a few adjustments
  // vb #1 is the timestamp
  // vb #2 is the id, represented as an Oid
  if ( raw_pdu->command == sNMP_PDU_TRAP)
  {
    Pdu temppdu;
    Vb tempvb;
    
    // vb #1 is the timestamp
    TimeTicks timestamp;
    tempvb.set_oid("1.3.6.1.2.1.1.3.0");   // sysuptime
    pdu.get_notify_timestamp( timestamp);
    tempvb.set_value ( timestamp);
    temppdu += tempvb;               	 
    
    // vb #2 is the id
    Oid trapid;
    tempvb.set_oid("1.3.6.1.6.3.1.1.5");
    pdu.get_notify_id( trapid);
    tempvb.set_value( trapid);
    temppdu += tempvb;
    
    // append the remaining vbs
    for ( int z=0;z<pdu.get_vb_count();z++) {
      pdu.get_vb( tempvb,z);
      temppdu += tempvb;
    }
    
    pdu = temppdu;          // reassign the pdu to the temp one
  }
  // load up the payload
  // for all Vbs in list, add them to the pdu
  int vb_count;
  Vb tempvb;
  Oid tempoid;
  SmiLPOID smioid;
  SmiVALUE smival;
  
  vb_count = pdu.get_vb_count();
  for (int z=0;z<vb_count;z++) {
    pdu.get_vb( tempvb,z);
    tempvb.get_oid( tempoid);
    smioid = tempoid.oidval();
    // clear the value portion, in case its
    // not already been done so by the app
    // writer
    // only do it in the case its a get,next or bulk
    if ((raw_pdu->command == sNMP_PDU_GET) ||
        (raw_pdu->command == sNMP_PDU_GETNEXT) ||
        (raw_pdu->command == sNMP_PDU_GETBULK))
      tempvb.set_null();
    status = convertVbToSmival( tempvb, 
                                &smival );
    if ( status != SNMP_CLASS_SUCCESS)
      return status;
    
    // add the vb to the raw pdu
    snmp_add_var( raw_pdu, 
                  smioid->ptr, 
                  (int) smioid->len,
                  &smival);
    
    freeSmivalDescriptor( &smival);
    
  }
  
  // ASN1 encode the pdu
  status = snmp_build( raw_pdu,
                       databuff,
                       (int *) &bufflen,
                       version,
                       community.data(),
                       (int) community.len());
  
  
  if ( status != 0) {
    valid_flag = FALSE;
    return SNMP_ERROR_WRONG_ENCODING;
  }
  valid_flag = TRUE;
  
  // prevention of SNMP++ Enterprise Oid death
  if ( enterprise.len() >0) {
    raw_pdu->enterprise = 0;
    raw_pdu->enterprise_length=0;
  }
  
  snmp_free_pdu( raw_pdu);
  
  return SNMP_CLASS_SUCCESS;
};

// load up a SnmpMessage
int SnmpMessage::load( unsigned char *data, 
                       unsigned long len)
{
  if ( len <= SNMP_MSG_LENGTH) {
    memcpy( (unsigned char *) databuff,
            (unsigned char *) data,
            (unsigned int) len);
    bufflen = len;
    valid_flag = TRUE;
  }
  else
    return SNMP_ERROR_WRONG_LENGTH;
  
  return SNMP_CLASS_SUCCESS;	
};


// unload the data into SNMP++ objects
int SnmpMessage::unload( Pdu &pdu,                 // Pdu object
                         OctetStr &community,      // community object
                         snmp_version &version)    // SNMP version #
{
  unsigned char community_name[255];
  unsigned long community_len;
  
  Pdu tmppdu;
  
  pdu = tmppdu;
  
  if ( !valid_flag)
    return SNMP_CLASS_INVALID;
  
  snmp_pdu *raw_pdu;
  raw_pdu = snmp_pdu_create(0);
  
  int status = snmp_parse( raw_pdu, databuff, community_name,
                           community_len, version, (int) bufflen);
  
  if ( status != 0) 
    return SNMP_CLASS_INTERNAL_ERROR;
  
  
  // load up the SNMP++ variables
  community.set_data(community_name, community_len);
  set_request_id( &pdu,raw_pdu->reqid);
  set_error_status( &pdu,(int) raw_pdu->errstat);
  set_error_index( &pdu,(int) raw_pdu->errindex);
  pdu.set_type( raw_pdu->command);
  
  // deal with trap parameters
  TimeTicks timestamp;
  timestamp = raw_pdu->time;
  pdu.set_notify_timestamp( timestamp);
  
  Oid tempoid(raw_pdu->enterprise,raw_pdu->enterprise_length);
  pdu.set_notify_enterprise(tempoid);
  
  // vbs
  Vb tempvb;
  struct   variable_list *vp;
  for(vp = raw_pdu->variables; vp; vp = vp->next_variable) {
    
    // extract the oid portion
    tempoid.set_data( (unsigned long *)vp->name,
                      ( unsigned int) vp->name_length);
    tempvb.set_oid( tempoid);
    
    // extract the value portion
    switch(vp->type) {
      
      // octet string
      case sNMP_SYNTAX_OCTETS:
      case sNMP_SYNTAX_OPAQUE:
        {
          OctetStr octets( (unsigned char *) vp->val.string,
                           (unsigned long) vp->val_len);
          tempvb.set_value( octets);
        }
      break;
      
      // object id
      case sNMP_SYNTAX_OID:
        {
          Oid oid( (unsigned long*) vp->val.objid,
                   (int) vp->val_len);
          tempvb.set_value( oid);
        }
      break;
      
      // timeticks
      case sNMP_SYNTAX_TIMETICKS:
        {
          TimeTicks timeticks( (unsigned long) *(vp->val.integer));
          tempvb.set_value( timeticks);
        }
      break;
      
      // 32 bit counter
      case sNMP_SYNTAX_CNTR32:
        {
          Counter32 counter32( (unsigned long) *(vp->val.integer));
          tempvb.set_value( counter32);
        }
      break;
      
      // 32 bit gauge
      case sNMP_SYNTAX_GAUGE32:
        {
          Gauge32 gauge32( (unsigned long) *(vp->val.integer));
          tempvb.set_value( gauge32);
        }
      break;
      
      // ip address
      case sNMP_SYNTAX_IPADDR:
        {
          char buffer[20];
          sprintf( buffer,"%d.%d.%d.%d",
                   vp->val.string[0],
                   vp->val.string[1],
                   vp->val.string[2],
                   vp->val.string[3]);
          IpAddress ipaddress( buffer);
          tempvb.set_value( ipaddress);
        }
      break;
      
      // 32 bit integer
      case sNMP_SYNTAX_INT:
        {
          SnmpInt32 int32( (long) *(vp->val.integer));
          tempvb.set_value( int32);
        }
      break;
      
      // 32 bit unsigned integer
      case sNMP_SYNTAX_UINT32:
        {
          SnmpUInt32 uint32( (unsigned long) *(vp->val.integer));
          tempvb.set_value( uint32);
        }
      break;
      
      // v2 counter 64's
      case sNMP_SYNTAX_CNTR64:
        {
          Counter64 c64(vp->val.counter64->high,vp->val.counter64->low);
          tempvb.set_value(c64);
        }
        break;
        
      case sNMP_SYNTAX_NULL:
        tempvb.set_null();
        break;
        
        // v2 vb exceptions
      case sNMP_SYNTAX_NOSUCHOBJECT:
      case sNMP_SYNTAX_NOSUCHINSTANCE:
      case sNMP_SYNTAX_ENDOFMIBVIEW:
        set_exception_status( &tempvb, vp->type);
        break;
        
      default:
        tempvb.set_null();
        
    } // end switch
    
    // append the vb to the pdu
    pdu += tempvb;
  }
  
  snmp_free_pdu( raw_pdu);
  
  return SNMP_CLASS_SUCCESS;	
};