On Wed, 29 May 2024 18:53:55 GMT, Anthony Scarpino <ascarp...@openjdk.org> wrote:
> Hi > > This change is to improve TLS 1.3 session resumption by allowing a TLS server > to send more than one resumption ticket per connection and clients to store > more. Resumption is a quick way to use an existing TLS session to establish > another session by avoiding the long TLS full handshake process. In TLS 1.2 > and below, clients can repeatedly resume a session by using the session ID > from an established connection. In TLS 1.3, a one-time "resumption ticket" > is sent by the server after the TLS connection has been established. The > server may send multiple resumption tickets to help clients that rapidly > resume connections. If the client does not have another resumption ticket, > it must go through the full TLS handshake again. The current implementation > in JDK 23 and below, only sends and store one resumption ticket. > > The number of resumption tickets a server can send should be configurable by > the application developer or administrator. [RFC > 8446](https://www.rfc-editor.org/rfc/rfc8446) does not specify a default > value. A system property called `jdk.tls.server.newSessionTicketCount` > allows the user to change the number of resumption tickets sent by the > server. If this property is not set or given an invalid value, the default > value of 3 is used. Further details are in the CSR. > > A large portion of the changeset is on the client side by changing the > caching system used by TLS. It creates a new `CacheEntry<>` type called > `QueueCacheEntry<>` that will store multiple values for a Map entry. src/java.base/share/classes/sun/security/ssl/SSLConfiguration.java line 202: > 200: if (nstServerCount == null || nstServerCount < 1 || > 201: nstServerCount > 10) { > 202: serverNewSessionTicketCount = 3; I'm always on the fence about this, but do you think it is worthwhile to put a debug log message here so folks can tell why their value is getting altered to a default 3? If we don't do it for other props then it's probably not worth it, but I thought I'd ask. src/java.base/share/classes/sun/security/ssl/SSLSessionImpl.java line 503: > 501: this.preSharedKey = new SecretKeySpec(b, alg); > 502: // Get identity len > 503: i = buf.get(); Given that this is just a small change to a large function it may not be important to change, but a lot of these X-byte lengths followed by arrays might be simplified with Record.getBytes8 or the other similar routines that handle longer length fields. But you wouldn't end up with a null byte[] when the length is zero, so that's a change, not necessarily a down-side. src/java.base/share/classes/sun/security/util/Cache.java line 683: > 681: > 682: // Limit the number of queue entries. > 683: private static final int MAXQUEUESIZE = 10; What do you think about making this tunable through the constructor, perhaps with a default value of 10? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/19465#discussion_r1626171765 PR Review Comment: https://git.openjdk.org/jdk/pull/19465#discussion_r1626184113 PR Review Comment: https://git.openjdk.org/jdk/pull/19465#discussion_r1628114149
