c# - SslStream, disable session caching

Question

The MSDN documentation says

The Framework caches SSL sessions as they are created and attempts to reuse a cached session for a new request, if possible. When attempting to reuse an SSL session, the Framework uses the first element of ClientCertificates (if there is one), or tries to reuse an anonymous sessions if ClientCertificates is empty.

How can I disable this caching?

At the moment I am experiencing a problem with a reconnect to a server (i.e., the first connection works good, but at attempt to reconnect the servers breaks the session). Restarting the application helps (but of course only for the first connection attempt). I assume the problem root is caching.

I've checked the packets with a sniffer, the difference is at just single place only at Client Hello messages:

First connection to the server (successful):

Second connection attempt (no program restart, failed):

The difference seems to be just the session identifier.

P.S. I'd like to avoid using 3rd-party SSL clients. Is there a reasonable solution?

_{This is a translation of this question from ru.stackoverflow}

Answer 1

Caching is handled inside SecureChannel - internal class that wraps SSPI and used by SslStream. I don't see any points inside that you can use to disable session caching for client connections.

You can clear cache between connections using reflection:

var sslAssembly = Assembly.GetAssembly(typeof(SslStream));

var sslSessionCacheClass = sslAssembly.GetType("System.Net.Security.SslSessionsCache");

var cachedCredsInfo = sslSessionCacheClass.GetField("s_CachedCreds", BindingFlags.NonPublic | BindingFlags.Static);
var cachedCreds = (Hashtable)cachedCredsInfo.GetValue(null);

cachedCreds.Clear();

But it's very bad practice. Consider to fix server side.