winextdll.c

开发snmp的开发包有两个开放的SNMP开发库

          case ASN_TIMETICKS:
          case ASN_OPAQUE:        
            
            pVarBindList.list->value.asnValue.number = *(var->val.integer);
            break;
              
          case ASN_OBJECT_ID:
            
            // Convert OID from Net-SNMP to Windows
            temp_oid = var->val.objid;
            temp_oid_length = var->val_len / sizeof(oid);           
            
            DEBUGMSGTL(("winExtDLL","Sizeof var->val.objid: %d\n", temp_oid_length));

            DEBUGMSGTL(("winExtDLL","OID: from user "));
            DEBUGMSGOID(("winExtDLL", temp_oid, temp_oid_length));
            DEBUGMSG(("winExtDLL","\n"));
            
            mySnmpVarBind->name.ids = (UINT *) SnmpUtilMemAlloc(sizeof (UINT) * temp_oid_length);

            if (mySnmpVarBind->name.ids) {
              // Actual copy
              for (i = 0; i < temp_oid_length; i++) {
                mySnmpVarBind->name.ids[i] = (UINT)temp_oid[i];
              }
              mySnmpVarBind->name.idLength = i;
              
              // Print OID
              DEBUGMSGTL(("winExtDLL","Windows OID length: %d\n",mySnmpVarBind->name.idLength));
              DEBUGMSGTL(("winExtDLL","Windows OID: "));
              DEBUGMSGWINOID(("winExtDLL", mySnmpVarBind));
              DEBUGMSG(("winExtDLL", "\n"));
            }
            else {
              DEBUGMSGTL(("winExtDLL", "\nyCould not allocate memory for Windows SNMP varbind.\n"));
              return SNMP_ERR_GENERR;
            }
            SnmpUtilOidCpy(&pVarBindList.list->value.asnValue.object, &mySnmpVarBind->name);
            //pVarBindList.list->value.asnValue.object = mySnmpVarBind->name;
            if (mySnmpVarBind)
              SnmpUtilVarBindFree(mySnmpVarBind);
            
          default:
            break;      
        }  

        if (xSnmpExtensionQueryEx) {
          DEBUGMSGTL(("winExtDLL", "Calling xSnmpExtensionQueryEx\n"));
          result = xSnmpExtensionQueryEx(SNMP_PDU_SET, 1, &pVarBindList, NULL, &pErrorStatus, &pErrorIndex);
        }
        else { 
          DEBUGMSGTL(("winExtDLL", "Calling xSnmpExtensionQuery\n"));
          result = xSnmpExtensionQuery(SNMP_PDU_SET, &pVarBindList, &pErrorStatus, &pErrorIndex);
        }

        DEBUGMSGTL(("winExtDLL", "win: Result of xSnmpExtensionQuery: %d\n",result));        
        DEBUGMSGTL(("winExtDLL", "win: Error status of xSnmpExtensionQuery: %d\n",pErrorStatus));
        DEBUGMSGTL(("winExtDLL", "win: asnType: %d\n",pVarBindList.list->value.asnType));

        if (result == 0) {
          DEBUGMSGTL(("winExtDLL", "\nyxWindows SnmpExtensionQuery failure.\n"));
          return SNMP_ERR_GENERR;
        }
        
        if (&pVarBindList)
          SnmpUtilVarBindListFree(&pVarBindList);

        if (pErrorStatus) {
          switch (pErrorStatus) {
            case SNMP_ERRORSTATUS_INCONSISTENTNAME:
              return SNMP_ERR_GENERR;
            default:
              return pErrorStatus;
              break;
          }
        }
      }
      break;     

    case MODE_SET_UNDO:
    case MODE_SET_COMMIT:
    case MODE_SET_FREE:

      break;
      
    default:
        snmp_log(LOG_WARNING, "unsupported mode for winExtDLL called (%d)\n",
                               reqinfo->mode);
        return SNMP_ERR_NOERROR;
    }

    return SNMP_ERR_NOERROR;
}

void winExtDLL_free_config_winExtDLL(void) {
}

void read_ExtensionAgents_list() {
  HKEY          hKey; 
  unsigned char * key_value = NULL;
  DWORD         key_value_size = 0;
  DWORD         key_value_type = 0;
  DWORD         valueSize = MAX_VALUE_NAME; 
  int           i;
  TCHAR         valueName[MAX_VALUE_NAME];
  TCHAR         valueName2[MAX_VALUE_NAME];
  DWORD         retCode;
  
  DEBUGMSGTL(("winExtDLL", "read_ExtensionAgents_list called\n"));

  /* The Windows SNMP service stores the list of extension agents to be loaded in the
   * registry under HKLM\SYSTEM\CurrentControlSet\Services\SNMP\Parameters\ExtensionAgents.
   * This list contains a list of other keys that contain the actual file path to the DLL.
   */

  /* Open SYSTEM\\CurrentControlSet\\Services\\SNMP\\Parameters\\ExtensionAgent */
  retCode = RegOpenKeyExA(
      HKEY_LOCAL_MACHINE, 
      "SYSTEM\\CurrentControlSet\\Services\\SNMP\\Parameters\\ExtensionAgents", 
      0, 
      KEY_QUERY_VALUE, 
      &hKey);
  
  if (retCode == ERROR_SUCCESS) {
    /* Enumerate list of extension agents.  This is a list of other keys that contain the
     * actual filename of the extension agent.  */
    for (i=0; retCode==ERROR_SUCCESS; i++) 
    { 
      valueSize = MAX_VALUE_NAME; 
      valueName[0] = '\0'; 
      retCode = RegEnumValue(
          hKey,
          i,
          valueName, 
          &valueSize, 
          NULL, 
          NULL,
          NULL,
          NULL);
      
      if (retCode == ERROR_SUCCESS ) 
      { 
        /* Get key name that contains the actual filename of the extension agent */
        DEBUGMSGTL(("winExtDLL", "-----------------------------------------\n"));
        DEBUGMSGTL(("winExtDLL", "Registry: (%d) %s\n", i+1, valueName));
        
        key_value_size = MAX_VALUE_NAME;
        if (RegQueryValueExA(
              hKey, 
              valueName, 
              NULL, 
              &key_value_type, 
              valueName2, 
              &key_value_size) == ERROR_SUCCESS) {
        }
        DEBUGMSGTL(("winExtDLL", "key_value: %s\n",valueName2));
        read_ExtensionAgents_list2(valueName2);
        extDLLs_index++;
      }
    }
    if (extDLLs_index)
      extDLLs_index--;
  }
}

void read_ExtensionAgents_list2(const TCHAR *keyName) {
  HKEY          hKey; 
  unsigned char * key_value = NULL;
  DWORD         key_value_size = 0;
  DWORD         key_value_type = 0;
  DWORD         valueSize = MAX_VALUE_NAME; 
  TCHAR         valueName[MAX_VALUE_NAME];
  TCHAR         valueNameExpanded[MAX_VALUE_NAME];
  int           i;
  DWORD         retCode;
  
  DEBUGMSGTL(("winExtDLL", "read_ExtensionAgents_list2 called\n"));
  DEBUGMSGTL(("winExtDLL", "Registry: Opening key %s\n", keyName));

  /* Open extension agent's key */
  retCode = RegOpenKeyExA(
      HKEY_LOCAL_MACHINE, 
      keyName, 
      0, 
      KEY_QUERY_VALUE, 
      &hKey);
  
  if (retCode == ERROR_SUCCESS) {
    /* Read Pathname value */

    DEBUGMSGTL(("winExtDLL", "Registry: Reading value for %s\n", keyName));
       
    key_value_size = MAX_VALUE_NAME;
    retCode = RegQueryValueExA(
        hKey, 
        "Pathname", 
        NULL, 
        &key_value_type, 
        valueName, 
        &key_value_size);
    
    if (retCode == ERROR_SUCCESS) {
      valueName[key_value_size-1] = NULL;               /* Make sure last element is a NULL */        
      DEBUGMSGTL(("winExtDLL", "Extension agent Pathname size: %d\n",key_value_size));
      DEBUGMSGTL(("winExtDLL", "Extension agent Pathname: %s\n",valueName));

      if (ExpandEnvironmentStrings(valueName, valueNameExpanded, MAX_VALUE_NAME)) {
        DEBUGMSGTL(("winExtDLL", "Extension agent Pathname expanded: %s\n",valueNameExpanded));
        if (extDLLs_index < MAX_WINEXT_DLLS) {

          extDLLs[extDLLs_index] = strdup(valueNameExpanded);
          
          if (extDLLs[extDLLs_index]) {
            strcpy(extDLLs[extDLLs_index], valueNameExpanded );
            DEBUGMSGTL(("winExtDLL", "Extension agent Pathname expanded extDLLs: %s\n",extDLLs[extDLLs_index]));
            DEBUGMSGTL(("winExtDLL", "Extension agent Pathname size: %d\n",strlen(extDLLs[extDLLs_index])));
          }
          else {
            DEBUGMSGTL(("winExtDLL", "Could not allocate memory for extDLLs[%d]\n",extDLLs_index));
          }
        }
      }
      else {
        DEBUGMSGTL(("winExtDLL", "ExpandEnvironmentStrings failed\n"));
      }      
    }
  }
}

// Called by alarm to check for traps waiting to be processed.
void subagentTrapCheck() {
  DWORD dwWaitResult;
  BOOL bResult;
  int i;
  netsnmp_variable_list *notification_vars = NULL;

  // Windows SNMP
  AsnObjectIdentifier   pEnterprise;
  AsnInteger            pGenericTrap;
  AsnInteger            pSpecificTrap;
  AsnTimeticks          pTimeStamp;
  SnmpVarBindList       pVariableBindings;
 
  DEBUGMSGTL(("winExtDLL", "subagentTrapMonitor called\n"));

  dwWaitResult = WaitForMultipleObjects(
      subagentTrapEvents_index,
      subagentTrapEvents,
      FALSE,
      0);

  if (! (dwWaitResult) || (dwWaitResult == WAIT_TIMEOUT))
    return;
  
  DEBUGMSGTL(("winExtDLL", "---------------------------------------------\n"));
  DEBUGMSGTL(("winExtDLL", "subagentTrapCheck found a trap event (index: %d)\n",dwWaitResult));
  
  /* Loop through all the winExtensionAgent's looking for a matching handler */
  for (i=0;  winExtensionAgent[i].xSnmpExtensionInit && i < MAX_WINEXT_DLLS; i++) {
    DEBUGMSGTL(("winExtDLL", "Looping through all the winExtensionAgent's looking for a matching trap handler.\n"));

    if (winExtensionAgent[i].subagentTrapEvent == subagentTrapEvents[dwWaitResult]) {
      DEBUGMSGTL(("winExtDLL", "Found match: "));
      DEBUGMSGOID(("winExtDLL", winExtensionAgent[i].name, winExtensionAgent[i].name_length));
      DEBUGMSG(("winExtDLL", "\n"));

      if (winExtensionAgent[i].xSnmpExtensionTrap)
        DEBUGMSGTL(("winExtDLL", "xSnmpExtensionTrap exists for this subagent\n"));
      else {
        DEBUGMSGTL(("winExtDLL", "xSnmpExtensionTrap does NOT exist for this subagent\n"));
        continue;
      }

      pEnterprise.ids = NULL;
      pEnterprise.idLength = 0;
      pGenericTrap = pSpecificTrap = NULL;
      pTimeStamp = 0;
      pVariableBindings.list = NULL;
      pVariableBindings.len = 0;

      DEBUGMSGTL(("winExtDLL", "Calling SnmpExtensionTrap\n"));
      bResult = winExtensionAgent[i].xSnmpExtensionTrap(
          &pEnterprise,
          &pGenericTrap,
          &pSpecificTrap,
          &pTimeStamp,
          &pVariableBindings);
      
      DEBUGMSGTL(("winExtDLL", "result of SnmpExtensionTrap call:  %d\n",bResult));

      
      DEBUGMSGTL(("winExtDLL", "GenericTrap: %d\n",pGenericTrap));
      DEBUGMSGTL(("winExtDLL", "SpecificTrap: %d\n",pSpecificTrap));

      if (pEnterprise.idLength)
        DEBUGMSGTL(("winExtDLL", "pEnterprise is not 0\n"));
      else
        DEBUGMSGTL(("winExtDLL", "pEnterprise is 0\n"));

      // Assume that if enterprise length is >0, it's a real trap and not a cleanup call
      // FIXME:  Not sure if this is correct.  Need to test with agent that sends a non-enterprise trap
      if (pEnterprise.idLength) {
        
        // Send the trap
        send_trap(
            &pEnterprise, 
            &pGenericTrap, 
            &pSpecificTrap, 
            &pTimeStamp,
            &pVariableBindings);
      }

      // Look for more traps from this agent (if result is TRUE there are more traps)
      while(bResult) {
        DEBUGMSGTL(("winExtDLL", "More traps to process.  Calling SnmpExtensionTrap again\n"));

        pEnterprise.ids = NULL;
        pEnterprise.idLength = 0;
        pGenericTrap = pSpecificTrap = NULL;
        pTimeStamp = 0;
        pVariableBindings.list = NULL;
        pVariableBindings.len = 0;