ed25519-zebra/ed25519jni/README.md

JNI

Code that provides a JNI for the library is included. Allows any JNI-using language to interact with specific ed25519-zebra calls and provides a minor analogue for some Rust classes, allowing for things like basic sanity checks of certain values. Tests written in Scala have also been included.

Compilation / Library Usage

To build the JNI code, there are several steps. The exact path forward depends on the user's preferred deployment method. No matter what, the following steps must be performed at the beginning.

• Run cargo build in the root directory. This generates the core Rust code.
• Run cargo build in the ed25519jni/rust subdirectory. This generates the Rust glue code libraries (libed25519jni.a and libed25519jni.{so/dylib}).

From here, there are two deployment methods: Direct library usage and JARs.

JAR

It's possible to generate a JAR that can be loaded into a project via SciJava's NativeLoader, along with the Java JNI interface file. There are two exta steps to perform after the mandatory compilation steps.

• Run jni_jar_prereq.sh from the ed25519/scripts subdirectory. This performs some JAR setup steps.
• Run sbt clean publishLocal from the ed25519jni/jvm subdirectory. This generates the final ed25519jni.jar file.

Direct library usage

(NOTE: Future work will better accommodate this option. For now, users will have to develop their own solutions.)

Use a preferred method to load the Rust core and JNI libraries directly as needed. If necessary, include the JNI Java files too.

Testing

Run sbt test from the ed25519jni/jvm directory. Note that, in order to run the tests, the JAR compilation method must be executed first.

Capabilities

Among other things, the JNI code can perform the following actions.

• Generate a random 32 byte signing key seed.
• Generate a 32 byte verification key from a signing key seed.
• Sign arbitrary data with a signing key seed.
• Verify a signature for arbitrary data with verification key bytes (32 bytes).