snmpeldl.cpp

windows的snmp api源码

/*++

Copyright (c) 1994	Microsoft Corporation

Module Name:

		SNMPELDL.CPP


Abstract:

		This module is the main extension agent DLL for the SNMP Event Log
		Extension Agent DLL.

		Standard tracing and logging routines are defined in this module.

		DLL initialization and termination routines are defined here.

		SNMP trap initialization and processing is defined here.

		Spawning of the log processing thread is done in this routine.

Author:

		Randy G. Braze (Braze Computing Services) Created 16 October 1994


Revision History:
        9 Feb 99    FlorinT: Removed warning event logs on startup (when registry parameters are not found)

        16 Dec 98   FlorinT: Added LoadPrimaryModuleParams and 'EALoad.*' files

        1 Dec 98    FlorinT: Remove psupportedView - it is freed by the SNMP master agent

		7 Feb 96    Moved tracing and logging to separate module.
                        Restructured building of varbinds to be outside of trap generation.
                        Calculated trap buffer length correctly.
                        Created varbind queue and removed event log buffer queue.

		28 Feb 96   Added code to support a performance threshold reached indicator.
                        Removed pointer references to varbindlist and enterpriseoid.

		10 Mar 96   Removed OemToChar coding and registry checking.
                        Modifications to read log file names from EventLog registry entries and not
                        from specific entries in the SNMP Extension Agent's registry entries.
                        Included SnmpMgrStrToOid as an internal function, as opposed to using the function
                        provided by MGMTAPI.DLL. SNMPTRAP.EXE will be called if MGMTAPI is called, which
                        will disable other agents from being able to receive any traps. All references
                        to MGMTAPI.DLL and MGMTAPI.H will be removed.
                        Added a ThresholdEnabled flag to the registry to indicate if the threshold values
                        were to be monitored or ignored.

		13 Mar 96   Modified StrToOid routine to append the BaseEnterpriseOID to the specified string
                        if the string passed does not start with a period. Otherwise, the string is
                        converted as normal.
                        Changed TraceFileName parameter in the registry from REG_SZ to REG_EXPAND_SZ.
                        Modified registry reading routine to accept REG_EXPAND_SZ parameters.
                        Added additional tracing.

		07 May 96   Removed SnmpUtilOidFree and use two SNMP_free. One for the OID's ids array and
                        one for the OID itself. Also added psupportedView to free memory at exit.

		26 Jun 96   Modified the StrToOid function such that strings without leading "." have the base
                        OID appended instead of strings with a leading ".".

--*/

extern "C"
{
#include <stdlib.h>
#include <windows.h>        // windows definitions
#include <string.h>         // string declarations
#include <snmp.h>           // snmp definitions
#include <snmpexts.h>       // extension agent definitions
#include "snmpelea.h"       // global dll definitions
#include "snmpeldl.h"       // module specific definitions
#include "snmpelmg.h"       // message definitions
}

extern	VOID				FreeVarBind(UINT,RFC1157VarBindList 	*);
#include "snmpelep.h"       // c++ variables and definitions
#include "EALoad.h"         // parameters loading functions

// MikeCure 4/3/98 hotfix for SMS Bug1 #20521
//===========================================
BOOL EnablePrivilege(VOID);

BOOL
StrToOid(
	IN			PCHAR							lpszStr,
		IN		OUT 	AsnObjectIdentifier 	*asnOid
	)

/*++

Routine Description:

		This routine will convert the string passed to an OID.


Arguments:

		lpszStr -		Address of a null terminated string in the form n.n...n.

		asnOid	-		Address of converted OID of the input string.


Return Value:

		TRUE	-		If the string was successfully converted.

		FALSE	-		If the string could not be converted.

--*/

{
		CHAR	tokens[] = TEXT(".");			// delimiters to scan for
		CHAR	*token; 										// token returned
		UINT	nTokens;										// number of tokens located
		UINT	i;														// temporary counter
		CHAR	szString[MAX_PATH*2+1]; 		// temporary string holder
		CHAR	szOrgString[MAX_PATH*2+1];		// temporary string holder
		CHAR	*szStopString;							// temporary string pointer

		WriteTrace(0x0a,"StrToOid: Entering routine to convert string to OID\n");
		WriteTrace(0x00,"StrToOid: String to convert is %s\n", lpszStr);

		nTokens = 0;											// reset counter

		if ( strlen(lpszStr) == 0 )
		{
				WriteTrace(0x14,"StrToOid: No strings found. Exiting with FALSE\n");
				return(FALSE);
		}

		if (lpszStr[0] != '.')
		{
				WriteTrace(0x0a,"StrToOid: BaseOID will not be appended to this OID\n");
				strcpy(szString, lpszStr);						// copy original string
		}
		else
		{
				WriteTrace(0x0a,"StrToOid: BaseOID %s will be appended to this OID\n", szBaseOID);
				strcpy(szString, szBaseOID);			// copy in base OID
				strcat(szString, TEXT("."));			// stick in the .
				strcat(szString, lpszStr);						// add in requested string
		}

		strcpy(szOrgString, szString);					// save this string

		token = strtok(szString, tokens);		// get first token

		while (token != NULL)
		{
				szStopString = token;							// set pointer to string
				strtoul(token, &szStopString, 10);		// check for valid values
				if ( (token == szStopString) || (*szStopString != NULL) )
				{
						WriteTrace(0x14,"StrToOid: String contains a non-numeric value. Exiting with FALSE\n");
						WriteLog(SNMPELEA_NON_NUMERIC_OID);
						return(FALSE);
				}

				nTokens++;												// increment number of tokens found
				token = strtok(NULL, tokens);	// get next token
		}

		if (nTokens == 0)
		{
				WriteTrace(0x14,"StrToOid: No strings found. Exiting with FALSE\n");
				return(FALSE);
		}

		WriteTrace(0x00,"StrToOid: %lu tokens found\n", nTokens);
		WriteTrace(0x0a,"StrToOid: Allocating storage for OID\n");

		asnOid->ids = (UINT *) SNMP_malloc(nTokens * sizeof(UINT)); 	// allocate integer array

		if (asnOid->ids == NULL)
		{
				WriteTrace(0x14,"StrToOid: Unable to allocate integer array for OID structure. Exiting with FALSE\n");
				WriteLog(SNMPELEA_CANT_ALLOCATE_OID_ARRAY);
				return(FALSE);
		}

		WriteTrace(0x00,"StrToOid: OID integer array storage allocated at %08X\n", asnOid->ids);

		asnOid->idLength = nTokens; 					// set size of array
		strcpy(szString, szOrgString);			// copy original string
		token = strtok(szString, tokens);		// get first token
		i = 0;															// set index to 0

		while (token != NULL)
		{
				asnOid->ids[i++] = strtoul(token, &szStopString, 10);	// convert string to number
				token = strtok(NULL, tokens);													// get next token
		}

		if (nTraceLevel == 0)
		{
				for (i = 0; i < nTokens; i++)
				{
						WriteTrace(0x00,"StrToOid: OID[%lu] is %lu\n",
								i, asnOid->ids[i]);
				}
		}

		WriteTrace(0x0a,"StrToOid: Exiting routine with TRUE\n");
		return(TRUE);
}


VOID
CloseStopAll(
	IN	VOID
	)

/*++

Routine Description:

		This routine will close the event handle used to terminate the extension agent dll.


Arguments:

		None


Return Value:

		None

--*/

{
		LONG	lastError;								// for GetLastError()

		if (hStopAll == NULL)
		{
				return;
		}

	WriteTrace(0x0a,"CloseStopAll: Closing handle to service shutdown event %08X\n",
				hStopAll);
		if ( !CloseHandle(hStopAll) )
		{
				lastError = GetLastError(); // save status
				WriteTrace(0x14,"CloseStopAll: Error closing handle for service shutdown event %08X; code %lu\n",
						hStopAll, lastError);
				WriteLog(SNMPELEA_ERROR_CLOSING_STOP_AGENT_HANDLE,
						HandleToUlong(hStopAll), lastError);
		}
}


VOID
CloseEventNotify(
	IN	VOID
	)

/*++

Routine Description:

		This routine will close the event handle used to notify SNMPELDL that a
		trap is waiting to be sent.


Arguments:

		None


Return Value:

		None

--*/

{
		LONG	lastError;								// for GetLastError()

		if (hEventNotify == NULL)
		{
				return;
		}

	WriteTrace(0x0a,"CloseEventNotify: Closing handle to event notify event %08X\n",
				hEventNotify);
		if ( !CloseHandle(hEventNotify) )		// close log processing routine shutdown event handle
		{
				lastError = GetLastError(); // save error status
				WriteTrace(0x14,"CloseEventNotify: Error closing handle for StopLog event %08X; code %lu\n",
						hEventNotify, lastError);
				WriteLog(SNMPELEA_ERROR_CLOSING_STOP_LOG_EVENT_HANDLE,
						HandleToUlong(hEventNotify), lastError);
		}
}


VOID
CloseRegNotify(
	IN	VOID
	)

/*++

Routine Description:

		This routine will close the event handle used to notify SNMPELDL that a
		registry key value has changed.


Arguments:

		None


Return Value:

		None

--*/

{
		LONG	lastError;								// for GetLastError()

		if (hRegChanged == NULL)
		{
				return;
		}

	WriteTrace(0x0a,"CloseRegNotify: Closing handle to registry key changed notify event %08X\n",
				hRegChanged);
		if ( !CloseHandle(hRegChanged) )		// close event handle
		{
				lastError = GetLastError(); // save error status
				WriteTrace(0x14,"CloseRegNotify: Error closing handle for registry key changed event %08X; code %lu\n",
						hRegChanged, lastError);
				WriteLog(SNMPELEA_ERROR_CLOSING_REG_CHANGED_EVENT_HANDLE,
						HandleToUlong(hRegChanged), lastError);
		}
}


VOID
CloseRegParmKey(
	IN	VOID
	)

/*++

Routine Description:

		This routine will close the registry key handle used to read the Parameters information
		from the registry.


Arguments:

		None


Return Value:

		None

--*/

{
		LONG	lastError;

		if (!fRegOk)
		{
				return;
		}

	WriteTrace(0x0a,"CloseRegParmKey: Closing Parameter key in registry\n");
		if ( (lastError = RegCloseKey(hkRegResult)) != ERROR_SUCCESS )	// close handle
		{
				WriteTrace(0x14,"CloseRegParmKey: Error closing handle for Parameters registry key %08X; code %lu\n",