Maintaining Security when Downloading Content

Your plug-in can use the DownloadContent method on the IWMSCacheProxyServer interface to download content from an origin server. However, some malicious server attacks can make it impossible for the download process to begin. It is therefore recommended that you monitor the process to determine whether content is actually being downloaded. You can do this by periodically calling the Win32 function GetFileSize or GetFileSizeEx to determine whether the file has grown. You can also implement the OnDownloadContentProgress method on the IWMSCacheProxyServerCallback interface, and set a timer to determine whether the server calls this method within an appropriate amount of time.

Other server attacks can send too much data during the download process. You can guard against this by specifying values for the lQuotaLow and lQuotaHigh parameters in the IWMSCacheProxyServer::DownloadContent method. These parameters contain the low-order and high-order bits of a 64-bit unsigned integer that specifies the maximum disk space that can be allotted for a download.

See Also (General)

• Windows Media Server Cache Proxy Functionality

See Also (Visual Basic .NET)

• IWMSCacheProxyServer.DownloadContentIWMSCacheProxyServer.DownloadContent (Visual Basic .NET)

• IWMSCacheProxyServerCallback.OnDownloadContentProgressIWMSCacheProxyServerCallback.OnDownloadContentProgress (Visual Basic .NET)

See Also (C#)

• IWMSCacheProxyServer.DownloadContentIWMSCacheProxyServer.DownloadContent (C#)

• IWMSCacheProxyServerCallback.OnDownloadContentProgressIWMSCacheProxyServerCallback.OnDownloadContentProgress (C#)

See Also (C++)

• IWMSCacheProxyServer::DownloadContent

• IWMSCacheProxyServerCallback::OnDownloadContentProgress