It's not ok for things to break for Java 8 users when they upgrade (even if they can fix it by changing a config). So, I think we need to change the KIP to offer more dynamic behavior: only enable TLS 1.3 if it's safe.
Ismael On Mon, May 18, 2020, 8:59 AM Nikolay Izhikov <nizhi...@apache.org> wrote: > > 1. I meant that `ssl.protocol` is TLSv1.2 while `ssl.enabled.protocols` > is `TLSv1.2, TLSv1.3`. How do these two configs interact > > `ssl.protocol` is what will be used, by default, in this KIP is stays > unchanged (TLSv1.2) Please, see [1] > `ssl.enabled.protocols` is list of protocols that *can* be used. This > value is just passed to the `SSLEngine` implementation. > Please, see DefaultSslEngineFactory#createSslEngine [2] > > > 2. My question is not about obsolete protocols, it is about people using > TLS 1.2 with specified cipher suites. How will that behave when TLS 1.3 is > enabled by default? > > They don’t change anything and all just work as expected on java11. > > > 3. An additional question is how does this impact Java 8 users? > > Yes. > If SSLEngine doesn’t support TLSv1.3 then java8 users should explicitly > modify `ssl.enabled.protocols` and set it to `TLSv1.2`. > > [1] > https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/security/ssl/DefaultSslEngineFactory.java#L218 > [2] > https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/security/ssl/DefaultSslEngineFactory.java#L164 > > > 18 мая 2020 г., в 17:34, Ismael Juma <ism...@juma.me.uk> написал(а): > > > > Nikolay, > > > > Thanks for the comments. More below: > > > > 1. I meant that `ssl.protocol` is TLSv1.2 while `ssl.enabled.protocols` > is `TLSv1.2, TLSv1.3`. How do these two configs interact? > > 2. My question is not about obsolete protocols, it is about people using > TLS 1.2 with specified cipher suites. How will that behave when TLS 1.3 is > enabled by default? > > 3. An additional question is how does this impact Java 8 users? Java 8 > will receive TLS 1.3 support later this year ( > https://java.com/en/jre-jdk-cryptoroadmap.html), but it currently does > not support it. One way to handle this would be to check if the underlying > JVM supports TLS 1.3 before enabling it. > > > > I hope this clarifies my questions. > > > > Ismael > > > > On Mon, May 18, 2020 at 6:44 AM Nikolay Izhikov <nizhi...@apache.org> > wrote: > > Hello, Ismael. > > > > Here is answers to your questions: > > > > > Quick question, the following is meant to include TLSv1.3 as well, > right? > > > Change the value of the SslConfigs.DEFAULT_SSL_ENABLED_PROTOCOLS to > «TLSv1.2» > > > > I propose to have the following value > SslConfigs.DEFAULT_SSL_ENABLED_PROTOCOLS = «TLSv1.2,TLSv.1.3» > > > > > 1. `ssl.protocol` would remain TLSv1.2 with this change. It would be > good to explain why that's OK. > > > > I think it covered by the following statements in KIP. > > If you know more trustworthy sources of this kind of information, > please, let me know. > > > > ``` > > For now, only TLS1.2 and TLS1.3 are recommended for the usage, other > versions of TLS considered as obsolete: > > • https://www.rfc-editor.org/info/rfc8446 > > • > https://en.wikipedia.org/wiki/Transport_Layer_Security#History_and_development > > > > ``` > > > > > 2. What is the behavior for people who have configured > `ssl.cipher.suites`? > > > The cipher suite names are different in TLS 1.3. What would be the > behavior > > > if the client requests TLS 1.3, but the server only has cipher suites > for > > > TLS 1.2? It would be good to explain the expected behavior and add > tests to verify it. > > > > I think those users should update > `SslConfigs.DEFAULT_SSL_ENABLED_PROTOCOLS` and enable required(but > obsolete) version of TLS they use. > > After one should migrate to the reliable TLS version. > > This reflected in the KIP: > > > > ``` > > Migration: Users who are using TLSv1.1 and TLSv1 should enable these > versions of the protocol with the explicit configuration property > "ssl.enabled.protocols" > > ``` > > > > > 25 февр. 2020 г., в 08:57, Nikolay Izhikov <nizhikov....@gmail.com> > написал(а): > > > > > > Hello. > > > > > > Any feedback on this? > > > > > > This change seems very simple, I can start vote right now if nothing > to discuss here. > > > > > >> 21 февр. 2020 г., в 15:18, Nikolay Izhikov <nizhikov....@gmail.com> > написал(а): > > >> > > >> Hello, > > >> > > >> I'd like to start a discussion of KIP [1] > > >> This is follow-up for the KIP-553 [2] > > >> > > >> Its goal is to enable TLSv1.3 by default. > > >> > > >> Your comments and suggestions are welcome. > > >> > > >> [1] > https://cwiki.apache.org/confluence/display/KAFKA/KIP-573%3A+Enable+TLSv1.3+by+default > > >> [2] > https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=142641956 > > > > > > >
