The QuerySecurityPackageInfo function retrieves information about a specified security package. This information includes the bounds on sizes of authentication information, credentials, and contexts.
SECURITY_STATUS QuerySecurityPackageInfo(
  SEC_CHAR * pszPackageName,   // name of package
  PSecPkgInfo *ppPackageInfo   // receives package information
);
 If the function succeeds, the return value is SEC_E_OK.
If the function fails, the return value is a nonzero error code.
The caller must call the FreeContextBuffer function to free the buffer returned in ppPackageInfo.