Add libsignal-jni-testing crate with test-only functions for Java

This parallels the exiting libsignal-jni crate but exports functions from 
libsignal-bridge-testing instead of libsignal-bridge. The crate is compiled as 
a separate shared object that is included in the published libsignal package, 
but which can be excluded at Android packaging time.

Cargo.toml

@@ -16,6 +16,7 @@ members = [
     "rust/zkgroup",
     "rust/bridge/ffi",
     "rust/bridge/jni",
+    "rust/bridge/jni/testing",
     "rust/bridge/node",
 ]
 default-members = [

acknowledgments/acknowledgments.html

@@ -47,7 +47,7 @@ <h1>Third Party Licenses</h1>
         <h2>Overview of licenses:</h2>
         <ul class="licenses-overview">
             <li><a href="#MIT">MIT License</a> (315)</li>
-            <li><a href="#AGPL-3.0">GNU Affero General Public License v3.0</a> (25)</li>
+            <li><a href="#AGPL-3.0">GNU Affero General Public License v3.0</a> (27)</li>
             <li><a href="#Apache-2.0">Apache License 2.0</a> (12)</li>
             <li><a href="#BSD-3-Clause">BSD 3-Clause &quot;New&quot; or &quot;Revised&quot; License</a> (8)</li>
             <li><a href="#ISC">ISC License</a> (6)</li>
@@ -736,11 +736,13 @@ <h4>Used by:</h4>
                     <li><a href="https://crates.io/crates/attest">attest 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/libsignal-ffi">libsignal-ffi 0.52.1</a></li>
                     <li><a href="https://crates.io/crates/libsignal-jni">libsignal-jni 0.52.1</a></li>
+                    <li><a href="https://crates.io/crates/libsignal-jni-testing">libsignal-jni-testing 0.52.1</a></li>
                     <li><a href="https://crates.io/crates/libsignal-node">libsignal-node 0.52.1</a></li>
                     <li><a href="https://crates.io/crates/signal-neon-futures">signal-neon-futures 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/signal-neon-futures-tests">signal-neon-futures-tests 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/libsignal-bridge">libsignal-bridge 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/libsignal-bridge-macros">libsignal-bridge-macros 0.1.0</a></li>
+                    <li><a href="https://crates.io/crates/libsignal-bridge-testing">libsignal-bridge-testing 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/libsignal-bridge-types">libsignal-bridge-types 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/libsignal-core">libsignal-core 0.1.0</a></li>
                     <li><a href="https://crates.io/crates/signal-crypto">signal-crypto 0.1.0</a></li>

acknowledgments/acknowledgments.md

@@ -669,7 +669,7 @@ For more information on this, and how to apply and follow the GNU AGPL, see
 
 ```
 
-## attest 0.1.0, libsignal-ffi 0.52.1, libsignal-jni 0.52.1, libsignal-node 0.52.1, signal-neon-futures 0.1.0, signal-neon-futures-tests 0.1.0, libsignal-bridge 0.1.0, libsignal-bridge-macros 0.1.0, libsignal-bridge-types 0.1.0, libsignal-core 0.1.0, signal-crypto 0.1.0, device-transfer 0.1.0, signal-media 0.1.0, libsignal-message-backup 0.1.0, libsignal-message-backup-macros 0.1.0, libsignal-net 0.1.0, signal-pin 0.1.0, poksho 0.7.0, libsignal-protocol 0.1.0, libsignal-svr3 0.1.0, usernames 0.1.0, zkcredential 0.1.0, zkgroup 0.9.0
+## attest 0.1.0, libsignal-ffi 0.52.1, libsignal-jni 0.52.1, libsignal-jni-testing 0.52.1, libsignal-node 0.52.1, signal-neon-futures 0.1.0, signal-neon-futures-tests 0.1.0, libsignal-bridge 0.1.0, libsignal-bridge-macros 0.1.0, libsignal-bridge-testing 0.1.0, libsignal-bridge-types 0.1.0, libsignal-core 0.1.0, signal-crypto 0.1.0, device-transfer 0.1.0, signal-media 0.1.0, libsignal-message-backup 0.1.0, libsignal-message-backup-macros 0.1.0, libsignal-net 0.1.0, signal-pin 0.1.0, poksho 0.7.0, libsignal-protocol 0.1.0, libsignal-svr3 0.1.0, usernames 0.1.0, zkcredential 0.1.0, zkgroup 0.9.0
 
 ```
 GNU AFFERO GENERAL PUBLIC LICENSE

acknowledgments/acknowledgments.plist

@@ -924,7 +924,7 @@ You should also get your employer (if you work as a programmer) or school, if an
 			<key>License</key>
 			<string>GNU Affero General Public License v3.0</string>
 			<key>Title</key>
-			<string>attest 0.1.0, libsignal-ffi 0.52.1, libsignal-jni 0.52.1, libsignal-node 0.52.1, signal-neon-futures 0.1.0, signal-neon-futures-tests 0.1.0, libsignal-bridge 0.1.0, libsignal-bridge-macros 0.1.0, libsignal-bridge-types 0.1.0, libsignal-core 0.1.0, signal-crypto 0.1.0, device-transfer 0.1.0, signal-media 0.1.0, libsignal-message-backup 0.1.0, libsignal-message-backup-macros 0.1.0, libsignal-net 0.1.0, signal-pin 0.1.0, poksho 0.7.0, libsignal-protocol 0.1.0, libsignal-svr3 0.1.0, usernames 0.1.0, zkcredential 0.1.0, zkgroup 0.9.0</string>
+			<string>attest 0.1.0, libsignal-ffi 0.52.1, libsignal-jni 0.52.1, libsignal-jni-testing 0.52.1, libsignal-node 0.52.1, signal-neon-futures 0.1.0, signal-neon-futures-tests 0.1.0, libsignal-bridge 0.1.0, libsignal-bridge-macros 0.1.0, libsignal-bridge-testing 0.1.0, libsignal-bridge-types 0.1.0, libsignal-core 0.1.0, signal-crypto 0.1.0, device-transfer 0.1.0, signal-media 0.1.0, libsignal-message-backup 0.1.0, libsignal-message-backup-macros 0.1.0, libsignal-net 0.1.0, signal-pin 0.1.0, poksho 0.7.0, libsignal-protocol 0.1.0, libsignal-svr3 0.1.0, usernames 0.1.0, zkcredential 0.1.0, zkgroup 0.9.0</string>
 			<key>Type</key>
 			<string>PSGroupSpecifier</string>
 		</dict>

bin/update_versions.py

@@ -36,8 +36,8 @@ def update_version(file, pattern, new_version):
 RUST_PATTERN = re.compile(r'^(pub const VERSION: &str = ")(.*)(")')
 
 
-def bridge_path(bridge):
-    return os.path.join('rust', 'bridge', bridge, 'Cargo.toml')
+def bridge_path(*bridge):
+    return os.path.join('rust', 'bridge', *bridge, 'Cargo.toml')
 
 
 VERSION_FILES = [
@@ -47,6 +47,7 @@ def bridge_path(bridge):
     (os.path.join('rust', 'core', 'src', 'version.rs'), RUST_PATTERN),
     (bridge_path('ffi'), CARGO_PATTERN),
     (bridge_path('jni'), CARGO_PATTERN),
+    (bridge_path('jni', 'testing'), CARGO_PATTERN),
     (bridge_path('node'), CARGO_PATTERN),
 ]
 

java/android/build.gradle

@@ -52,6 +52,7 @@ android {
     packagingOptions {
         jniLibs {
             pickFirst 'lib/*/libsignal_jni.so'
+            pickFirst 'lib/*/libsignal_jni_testing.so'
         }
     }
 

java/build.gradle

@@ -35,7 +35,7 @@ subprojects {
     spotless {
         java {
             target('**/*.java')
-            targetExclude('**/Native.java')
+            targetExclude('**/Native.java', '**/NativeTesting.java')
             importOrder()
             removeUnusedImports()
 
@@ -76,7 +76,7 @@ clean.dependsOn([cargoClean, cleanJni])
 
 // PUBLISHING
 
-ext.setUpSigningKey = { signingExt -> 
+ext.setUpSigningKey = { signingExt ->
     def signingKeyId = findProperty("signingKeyId")
     def signingKey = findProperty("signingKey")
     def signingPassword = findProperty("signingPassword")

java/build_jni.sh

@@ -53,9 +53,10 @@ while [ "${1:-}" != "" ]; do
             # https://github.com/rust-lang/rfcs/issues/2771
             export CARGO_PROFILE_RELEASE_LTO=thin
             FEATURES+=("testing-fns")
-            echo_then_run cargo build -p libsignal-jni --release --features "${FEATURES[*]}"
+            echo_then_run cargo build -p libsignal-jni -p libsignal-jni-testing --release ${FEATURES:+--features "${FEATURES[*]}"}
             if [[ -z "${CARGO_BUILD_TARGET:-}" ]]; then
                 copy_built_library target/release signal_jni "${DESKTOP_LIB_DIR}/"
+                copy_built_library target/release signal_jni_testing "${DESKTOP_LIB_DIR}/"
             fi
             exit
             ;;
@@ -136,5 +137,5 @@ target_for_abi() {
 
 for abi in "${android_abis[@]}"; do
     rust_target=$(target_for_abi "$abi")
-    echo_then_run cargo build -p libsignal-jni --release ${FEATURES:+--features "${FEATURES[*]}"} -Z unstable-options --target "$rust_target" --out-dir "${ANDROID_LIB_DIR}/$abi"
+    echo_then_run cargo build -p libsignal-jni -p libsignal-jni-testing --release ${FEATURES:+--features "${FEATURES[*]}"} -Z unstable-options --target "$rust_target" --out-dir "${ANDROID_LIB_DIR}/$abi"
 done

java/shared/java/org/signal/libsignal/internal/Native.java

@@ -24,13 +24,23 @@
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.concurrent.Future;
 import java.util.UUID;
 import java.util.Map;
 
 public final class Native {
-  private static void copyToTempFileAndLoad(InputStream in, String name) throws IOException {
-    File tempFile = Files.createTempFile(null, name).toFile();
+  private static Path tempDir;
+
+  private static void copyToTempDirAndLoad(InputStream in, String name) throws IOException {
+    // This isn't thread-safe but that's okay because it's only ever called from
+    // static initializers, which are themselves thread-safe.
+    if (tempDir == null) {
+      tempDir = Files.createTempDirectory("libsignal");
+      tempDir.toFile().deleteOnExit();
+    }
+
+    File tempFile = Files.createFile(tempDir.resolve(name)).toFile();
     tempFile.deleteOnExit();
 
     try (OutputStream out = new FileOutputStream(tempFile)) {
@@ -44,28 +54,35 @@ private static void copyToTempFileAndLoad(InputStream in, String name) throws IO
     System.load(tempFile.getAbsolutePath());
   }
 
-  /*
-  If libsignal_jni is embedded within this jar as a resource file, attempt
-  to copy it to a temporary file and then load it. This allows the jar to be
-  used even without a shared library existing on the filesystem.
-  */
-  private static void loadLibrary() {
-    try {
-      String libraryName = System.mapLibraryName("signal_jni");
-      try (InputStream in = Native.class.getResourceAsStream("/" + libraryName)) {
-        if (in != null) {
-          copyToTempFileAndLoad(in, libraryName);
-        } else {
-          System.loadLibrary("signal_jni");
-        }
+  /**
+   * If the library is embedded within this jar as a resource file, attempt to
+   * copy it to a temporary file and then load it. This allows the jar to be
+   * used even without a shared library existing on the filesystem.
+   *
+   * Package-private to allow the NativeTest class to load its shared library.
+   * This method should only be called from a static initializer.
+   */
+  static void loadLibrary(String name) throws IOException {
+    String libraryName = System.mapLibraryName(name);
+    try (InputStream in = Native.class.getResourceAsStream("/" + libraryName)) {
+      if (in != null) {
+        copyToTempDirAndLoad(in, libraryName);
+      } else {
+        System.loadLibrary(name);
       }
+    }
+  }
+
+  private static void loadNativeCode() {
+    try {
+      loadLibrary("signal_jni");
     } catch (Exception e) {
       throw new RuntimeException(e);
     }
   }
 
   static {
-    loadLibrary();
+    loadNativeCode();
     initializeLibrary();
   }
 

java/shared/java/org/signal/libsignal/internal/NativeTesting.java

@@ -0,0 +1,48 @@
+//
+// Copyright (C) 2024 Signal Messenger, LLC.
+// SPDX-License-Identifier: AGPL-3.0-only
+//
+
+// WARNING: this file was automatically generated
+
+package org.signal.libsignal.internal;
+
+import org.signal.libsignal.protocol.message.CiphertextMessage;
+import org.signal.libsignal.protocol.state.IdentityKeyStore;
+import org.signal.libsignal.protocol.state.SessionStore;
+import org.signal.libsignal.protocol.state.PreKeyStore;
+import org.signal.libsignal.protocol.state.SignedPreKeyStore;
+import org.signal.libsignal.protocol.state.KyberPreKeyStore;
+import org.signal.libsignal.protocol.groups.state.SenderKeyStore;
+import org.signal.libsignal.protocol.logging.Log;
+import org.signal.libsignal.protocol.logging.SignalProtocolLogger;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.concurrent.Future;
+import java.util.UUID;
+import java.util.Map;
+
+public final class NativeTesting {
+  private static void loadNativeCode() {
+    try {
+      Native.loadLibrary("signal_jni_testing");
+    } catch (Exception e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  static {
+    loadNativeCode();
+  }
+
+  private NativeTesting() {}
+
+  public static native int test_only_fn_returns_123();
+}

java/shared/test/java/org/signal/libsignal/internal/NativeTestingTest.java

@@ -0,0 +1,18 @@
+//
+// Copyright 2024 Signal Messenger, LLC.
+// SPDX-License-Identifier: AGPL-3.0-only
+//
+
+package org.signal.libsignal.internal;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+public class NativeTestingTest {
+  @Test
+  public void canCallNativeTestingFns() throws Exception {
+    int result = NativeTesting.test_only_fn_returns_123();
+    assertEquals(123, result);
+  }
+}

rust/bridge/jni/bin/Native.java.in

@@ -24,13 +24,23 @@ import java.io.InputStream;
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import java.nio.file.Files;
+import java.nio.file.Path;
 import java.util.concurrent.Future;
 import java.util.UUID;
 import java.util.Map;
 
 public final class Native {
-  private static void copyToTempFileAndLoad(InputStream in, String name) throws IOException {
-    File tempFile = Files.createTempFile(null, name).toFile();
+  private static Path tempDir;
+
+  private static void copyToTempDirAndLoad(InputStream in, String name) throws IOException {
+    // This isn't thread-safe but that's okay because it's only ever called from
+    // static initializers, which are themselves thread-safe.
+    if (tempDir == null) {
+      tempDir = Files.createTempDirectory("libsignal");
+      tempDir.toFile().deleteOnExit();
+    }
+
+    File tempFile = Files.createFile(tempDir.resolve(name)).toFile();
     tempFile.deleteOnExit();
 
     try (OutputStream out = new FileOutputStream(tempFile)) {
@@ -44,28 +54,35 @@ public final class Native {
     System.load(tempFile.getAbsolutePath());
   }
 
-  /*
-  If libsignal_jni is embedded within this jar as a resource file, attempt
-  to copy it to a temporary file and then load it. This allows the jar to be
-  used even without a shared library existing on the filesystem.
-  */
-  private static void loadLibrary() {
-    try {
-      String libraryName = System.mapLibraryName("signal_jni");
-      try (InputStream in = Native.class.getResourceAsStream("/" + libraryName)) {
-        if (in != null) {
-          copyToTempFileAndLoad(in, libraryName);
-        } else {
-          System.loadLibrary("signal_jni");
-        }
+  /**
+   * If the library is embedded within this jar as a resource file, attempt to
+   * copy it to a temporary file and then load it. This allows the jar to be
+   * used even without a shared library existing on the filesystem.
+   *
+   * Package-private to allow the NativeTest class to load its shared library.
+   * This method should only be called from a static initializer.
+   */
+  static void loadLibrary(String name) throws IOException {
+    String libraryName = System.mapLibraryName(name);
+    try (InputStream in = Native.class.getResourceAsStream("/" + libraryName)) {
+      if (in != null) {
+        copyToTempDirAndLoad(in, libraryName);
+      } else {
+        System.loadLibrary(name);
       }
+    }
+  }
+
+  private static void loadNativeCode() {
+    try {
+      loadLibrary("signal_jni");
     } catch (Exception e) {
       throw new RuntimeException(e);
     }
   }
 
   static {
-    loadLibrary();
+    loadNativeCode();
     initializeLibrary();
   }