GetTokenInformation

GetTokenInformation is a Windows API function that retrieves various pieces of information about an access token. An access token is a security object that describes the security context of a process or thread. This function allows a caller to query attributes such as the token's user identity, privileges, group memberships, and logon session.

The function takes several arguments, including a handle to the access token, a token information class that specifies the type of information to retrieve, a buffer to store the retrieved information, the size of the buffer, and a variable to receive the number of bytes written to the buffer. The token information class is an enumeration that defines many possible values, such as TokenUser, TokenGroups, or TokenPrivileges.

By using GetTokenInformation, developers can programmatically inspect and understand the security context of different parts of a Windows system. This is essential for tasks like implementing access control checks, managing user privileges, or auditing security-related events. For instance, one might use GetTokenInformation to determine if a process has specific administrative privileges before allowing it to perform a sensitive operation. The function is a fundamental tool for security-aware programming on the Windows platform.