ZipFile.isSignatureRelated returns true for files in META-INF subdirectories

[Alan Bateman]

Forwarding to security-dev as that is where issues around signed JARs 
are usually discussed.

-Alan.


On 10/01/2023 17:00, Eirik Bjørsnøs wrote:
> Hi,
>
> ZipFile.isSignatureRelated currently returns true for paths such as 
> the following:
>
> META-INF/libraries/org.bouncycastle:bcprov-jdk15on:jar-1.70/META-INF/BC2048KE.DSA
>
> While this path does start with "META-INF/" and ends with ".DSA", 
> the file does not live in the META-INF/ directory _directly_, but 
> rather several directories below.
>
> This causes such .DSA files to be incorrectly (?) included in the 
> verification of META-INF/MANIFEST.MF in JarFile.initializeVerifier, 
> which then fails with:
>
>     Exception in thread "main" java.lang.SecurityException: Invalid
>     signature file digest for Manifest main attributes
>     at
>     java.base/sun.security.util.SignatureFileVerifier.processImpl(SignatureFileVerifier.java:340)
>     at
>     java.base/sun.security.util.SignatureFileVerifier.process(SignatureFileVerifier.java:282)
>     at
>     java.base/java.util.jar.JarVerifier.processEntry(JarVerifier.java:327)
>     at java.base/java.util.jar.JarVerifier.update(JarVerifier.java:239)
>     at
>     java.base/java.util.jar.JarFile.initializeVerifier(JarFile.java:760)
>     at
>     java.base/java.util.jar.JarFile.ensureInitialization(JarFile.java:1058)
>     at
>     java.base/java.util.jar.JavaUtilJarAccessImpl.ensureInitialization(JavaUtilJarAccessImpl.java:72)
>     at
>     java.base/jdk.internal.loader.URLClassPath$JarLoader$2.getManifest(URLClassPath.java:883)
>     at
>     java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:848)
>     at
>     java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:760)
>     at
>     java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:681)
>     at
>     java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:639)
>     at
>     java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
>     at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) 
>
>
> A few questions:
>
> 1: Where Is the exact location of signature related files specified?
>
> 2: Is the current behaviour indeed incorrect?
>
> 3: Should ZipFile.isSignatureRelated be updated such that it only 
> matches signature related files which reside exactly in "META-INF/" ?
>
> The context for this is that I'm making a fat jar Maven plugin which 
> embeds dependency jars by "unpacking" them into subdirectories of 
> META-INF/libraries/.
>
> Cheers,
> Eirik.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/security-dev/attachments/20230113/fe979f16/attachment.htm>