User Guide

Chapter 7 TunnelGuard SRS Builder 351
Nortel Secure Network Access Switch 4050 User Guide
2 In the Available Expressions area, select the desired expression and click the
Delete Expression button.
TunnelGuard support for API calls
TunnelGuard can interact with other software vendor applications. In addition to
its own checks, TunnelGuard can be configured to communicate with other
applications and ask for their status. The result of the status check is treated the
same as other checks and is reported back to the server. This capability allows
administrators to use TunnelGuard to retrieve status from other software
packages, such as personal firewalls and virus checkers, to make sure they are
running properly.
Making API calls
TunnelGuard requires a Windows Platform DLL that implements at least one
common entry point as described below.
Windows
#include <windows.h>
/* return values */
#define STATUS_SUCCESS 0
#define STATUS _FAILURE -1
#define STATUS_REQUIRES_UPDATE 1
/* simple check */
int WINAPI CheckStatus(void);
This API blocks until one of the required status, as mentioned above, is returned
in 10 seconds or less. If an answer is not returned in a timely manner, it is assumed
the software is unavailable, and the call times out and returns an error message.
Note: You cannot delete an expression that is used in a TunnelGuard
rule.