On 09.11.2009 17:16, Mark Thomas wrote: > Konstantin Kolinko wrote: >> 2009/11/9 Mark Thomas <ma...@apache.org>: >>> Summarising the information gathered so far from various channels >>> (thanks to Bill B., Bill W. & Rainer who have done most of the actual >>> work to find the info below). >>> >>> BIO/NIO connectors using JSSE. >>> Vulnerable when renegotiation is triggered by the client or server. >>> We could prevent server initiated renegotiation (and probably break the >>> majority of configurations using CLIENT-CERT). >>> We can't do anything to prevent client initiated renegotiation. >>> >>> APR/native connector using OpenSSL >>> It is vulnerable when renegotiation is triggered by the client or by the >>> server. >>> Client triggered negotiation is supported. >>> Server triggered negotiation will be supported from 1.1.17 onwards. >>> >>> OpenSSL 0.9.8l disables negotiation by default >>> >>> >>> In terms of what this means for users: >>> >>> BIO/NIO >>> - There isn't anything we can do in Tomcat to stop client >>> initiated renegotiation so it is a case of waiting for the JVM >>> vendors to respond. >>> >>> APR/native >>> - Re-building their current version with 0.9.8l will protect >>> users at the risk of breaking any configurations that >>> require renegotiation. >>> - We can release 1.1.17 with the binaries built with 0.9.8l. This >>> will also protect users at the risk of breaking any >>> configurations that require renegotiation. Mladen is doing this >>> now. >>> - Supporting renegotiation whilst avoiding the vulnerability will >>> require a protocol fix. In the meantime, we could port port >>> r833582 from httpd which would disable client triggered >>> renegotiation for OpenSSL < 0.9.8l (which may help some users >>> who can't easily change their OpenSSl version and release 1.1.18 >>> with this fix >>> - Once the protocol is fixed, release 1.1.next bundled with the >>> appropriate version of OpenSSL >>> >>> >>> Have I got my facts right above? If so, any objections to posting the >>> above to the users@ and announce@ lists along with adding something to >>> the security pages? >>> >>> Mark >>> >> >> +1 >> >> s/negotiation/renegotiation/ >> s/port port/port/ > > Noted. I'll get the notice out. > >> A question: >> My understanding of renegotiation is that it changes SSL session. Is >> it possible to observe changes in the value of SSL sessionId? I doubt >> so, but may be? >> We read that value once and provide it to our users as >> "javax.servlet.request.ssl_session" request attribute. > > Hmm. Interesting. I need to do some testing :)
Yes, using the naive openssl test with s_client and the "R" command, the session id changes. In order to find out, whether this is optional behaviour or will always happen, I guess we would need to ask on the openssl dev list, which I will do in a minute :) > I'll add something along the lines of "We are currently evaluating a > number of possible work-arounds prior to a protocol fix becoming > available. Discussion is happening on the dev list and any significant > developments will be posted to the users@ and announce@ mailing lists. +1 --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
