On 1/23/19 8:59 AM, Sean Mullan wrote:
On 1/22/19 8:50 PM, Bernd Eckenfels wrote:
I don’t think the launcher is doing this, it is the class loader, that’s nothing new. You can turn on verbose security debug to see it in all versions.

Yes, and it only verifies the signature(s) on the JAR. It doesn't validate the certificate chain.

--Sean

I noticed that trying to identify the higher memory usage after what looks like a big application is loaded. I am doing memory profiling and notice JarFile taking more memory that on Java 8. Still need to detect the real cause for an independent test case. We probably didn't notice this slowdown before because Oracle's JNLP implementation was slow enough at startup.

IMHO the class library should not do doing signature checks without certificate validation, because it doesn't give any protection if the signature is not verified, the only thing it could do now is to detect some random bit flips, that maybe the Zip format CRC detect before that. With no certificate verification the signature could be replaced by anybody with bad intentions.

Maybe adding a constructor flag to URLClassloader to pass to JarFile to skip verification and a system property to tell the Java startup code to skip verification of java.class.path (just for compatibility with old code that expect it to be done). There is precedent of other runtimes that added options to disable this, like CLR [1] (Ii not only verified signatures, It do CRL/OSCP checks too)

Our new launcher replacing JNLP now do signature verification in native code, at download time, and install on a system area (not user home directory), so signature verification at application launch is a slowdown we want to avoid, but think on another kind of users, those deploying to OS Stores (for example Windows Store), why add the slowdown of verification when the application is verified by the store client at install time?, this could help these situations too.

Note: This can be avoided removing the signatures of all JARs if you distribute to an OS store, there are a few libraries that distribute their JARs signed (The old Java Help framework comes to my mind right now)

[1] https://blogs.msdn.microsoft.com/shawnfa/2007/05/07/bypassing-the-authenticode-signature-check-on-startup/



--
https://Bernd.eckenfels.net

________________________________
Von: core-libs-dev <core-libs-dev-boun...@openjdk.java.net> im Auftrag von Robert Marcano <rob...@marcanoonline.com>
Gesendet: Mittwoch, Januar 23, 2019 2:18 AM
An: Alan Bateman
Cc: OpenJDK Dev list; core-libs-dev Libs
Betreff: Re: High memory usage / leaks was: Best mailing list for JVM embedding

On Tue, Jan 22, 2019, 5:53 AM Alan Bateman <alan.bate...@oracle.com wrote:

On 22/01/2019 4:48 am, Robert Marcano wrote:
:

So the question now is, why signed jars could affect the memory usage
of an application (we aren't doing JAR verification on our custom
launcher, yet), just by being on the java.class.path? IIRC the
initial application classpath JARs were never verified previously (by
the java launcher alone, without JNLP around).

Note: Tested with JARs signed with a self signed certificate and with
one signed with a private CA. At most, signing the JARs could slow
down the start up if it is now expected to these being verified by
the java launcher (is it true?) but not higher memory usage and no
reductions after a GC cycle but constants heap size increases.
Signed JARs can be expensive to verify, esp. on first usage as the
verification is likely to result in early loading of a lot of security
classes and infrastructure. If you can narrow down the apparently memory
leak to a small test case with analysis to suggest it's a JDK bug then
it would be good to get a bug submitted.

-Alan


Greeting. Sure, I will work on a distributable reproduction of the problem today but it is new to me that the java launcher do JARs verification now.
If it is doing it I doesn't make sense to me, because a self signed or
unrecognized CA doesn't trigger a validation error.



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