feat: add native agent to intercept class and read annotations (#26)

* added first version of native agent

* example added

* add test app

* add files to reproduce prototype

* up

* fix: add JVM option to compiler plugin

* initialise capabilities

* set capabilities

* attach all potential capabilities

* feat: get stack trace at runtime and print methodids

* small changes in test project

* first version rust agent

* improving code safety

* constant pool parsing in progress

* agennt c test

* update c native

* small change toy project

* refactor and fix problem in using getAnnotations()

* update commands

* rust agent in progress (fix of getAnnotations

* fix bug recursion onMethodEntry

* fix recursion problem with onMethodEntry event

* update to filter just for classportInfo annotation

* path fixing

* readme update

* code cleaning

* code cleaning

---------

Co-authored-by: serenacofano <[email protected]>

Author: algomaster99

.gitignore

@@ -9,3 +9,8 @@ target/
 
 # vscode settings
 settings.json
+
+# Project relate files
+*.so
+classport-files/
+

.idea/runConfigurations/AgentLoader.xml

@@ -0,0 +1,14 @@
+[package]
+name = "cargo_agent"
+version = "0.1.0"
+edition = "2021"
+build = "build.rs"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+
+[build-dependencies]
+bindgen = "0.71.0"
+

cargo_agent/cargo_agent/Cargo.lock

@@ -0,0 +1,27 @@
+## Rust Agent (WIP)
+Here is an agent in Rust.
+
+* lib.rs is the agent (for the moment just intercept onMethodEntry event and print "capitalize" when this method is intercepted);
+* build.rs is the code that generate the binding of jvmti.h. It uses [rust-bindgen](https://rust-lang.github.io/rust-bindgen/) 
+
+### To use it
+
+Requirements: see [bindgen guide](https://rust-lang.github.io/rust-bindgen/requirements.html).
+
+- set the required environment variables
+
+```
+export JVM_LIB_PATH=<path-to-your-jdk-instalaltion>/libexec/openjdk.jdk/Contents/Home/lib/server
+export JVM_INCLUDE_PATH=<path-to-jvmti.h> 
+export JNI_INCLUDE_PATH=<path-to-jni.h>
+```
+
+- compile the project:
+
+`cargo build --release`
+
+- run the agent:
+
+`java -agentpath:/path/to/target/release/libmy_java_agent.dylib -jar your_app.jar`
+
+

cargo_agent/cargo_agent/Cargo.toml

@@ -0,0 +1,29 @@
+use std::env;
+use std::path::PathBuf;
+
+fn main() {
+    println!("OUT_DIR: {}", env::var("OUT_DIR").unwrap());
+
+    let jvm_lib_path = env::var("JVM_LIB_PATH").unwrap_or_else(|_| "/usr/local/Cellar/openjdk/23.0.2/libexec/openjdk.jdk/Contents/Home/lib/server".to_string());
+    let jvm_include_path = env::var("JVM_INCLUDE_PATH").unwrap_or_else(|_| "/usr/local/opt/openjdk@23/include/jvmti.h".to_string());
+    let jni_include_path = env::var("JNI_INCLUDE_PATH").unwrap_or_else(|_| "/usr/local/opt/openjdk@23/include/jni.h".to_string());
+
+    println!("cargo:rustc-link-search={}", jvm_lib_path);
+    println!("cargo:rustc-link-lib=jvm");
+
+    let bindings = bindgen::Builder::default()
+        .header(jvm_include_path)
+        .header(jni_include_path)
+        .blocklist_function("Agent_OnLoad")
+        .blocklist_function("Agent_OnUnload")
+        // Tell cargo to invalidate the built crate whenever any of the
+        // included header files changed.
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
+        .generate()
+        .expect("Unable to generate bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("Couldn't write bindings!");
+}