Attachment encryption

library/build.gradle.kts

@@ -40,6 +40,14 @@ android {
                 "proguard-rules.pro"
             )
         }
+
+        debug {
+            packaging {
+                jniLibs {
+                    keepDebugSymbols += "**/*.so"
+                }
+            }
+        }
     }
 
     compileOptions {

library/src/androidTest/kotlin/network/loki/messenger/libsession_util/image/GifUtilsTest.kt

@@ -0,0 +1,62 @@
+package network.loki.messenger.libsession_util.image
+
+import android.graphics.ImageDecoder
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.sessionfoundation.libsession_util.test.R
+
+@RunWith(AndroidJUnit4::class)
+class GifUtilsTest {
+    @Test
+    fun testReencodeGif() {
+
+        for (outputSize in listOf(200, 400, 600)) {
+            val output = InstrumentationRegistry.getInstrumentation()
+                .targetContext
+                .applicationContext
+                .resources
+                .openRawResource(R.raw.earth).use { input ->
+                    GifUtils.reencodeGif(
+                        input = input,
+                        timeoutMills = 100_000L,
+                        targetWidth = outputSize,
+                        targetHeight = outputSize
+                    )
+                }
+
+            ImageDecoder.decodeDrawable(
+                ImageDecoder.createSource(output)
+            ) { decoder, info, source ->
+                assertEquals(outputSize, info.size.width)
+                assertEquals(outputSize, info.size.height)
+                assertTrue(info.isAnimated)
+            }
+        }
+    }
+
+    @Test
+    fun testCheckAnimatedGifWorks() {
+        assertTrue(
+            InstrumentationRegistry.getInstrumentation()
+                .targetContext
+                .applicationContext
+                .resources
+                .openRawResource(R.raw.earth)
+                .use(GifUtils::isAnimatedGif)
+        )
+
+        assertFalse(
+            InstrumentationRegistry.getInstrumentation()
+                .targetContext
+                .applicationContext
+                .resources
+                .openRawResource(R.raw.sunflower_noanim)
+                .use(GifUtils::isAnimatedGif)
+        )
+    }
+}

library/src/main/cpp/CMakeLists.txt

@@ -15,8 +15,6 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_FLAGS -Wno-deprecated-declarations)
 
-set(CMAKE_BUILD_TYPE Release)
-
 # Creates and names a library, sets it as either STATIC
 # or SHARED, and provides the relative paths to its source code.
 # You can define multiple libraries, and CMake builds them for you.
@@ -26,6 +24,55 @@ set(STATIC_BUNDLE ON)
 set(ENABLE_ONIONREQ OFF)
 add_subdirectory(../../../../libsession-util libsession)
 
+include(FetchContent)
+
+
+## Catering for libwebp
+set(BUILD_SHARED_LIBS OFF CACHE BOOL "" FORCE)
+set(WEBP_BUILD_ANIM_UTILS ON CACHE BOOL "" FORCE)
+set(WEBP_BUILD_LIBWEBPMUX ON CACHE BOOL "" FORCE)
+
+FetchContent_Declare(
+        webp
+        GIT_REPOSITORY https://chromium.googlesource.com/webm/libwebp
+        GIT_TAG        v1.6.0
+)
+
+FetchContent_MakeAvailable(webp)
+
+## Catering for libyuv - to rescale images
+FetchContent_Declare(
+        libyuv
+        GIT_REPOSITORY https://chromium.googlesource.com/libyuv/libyuv
+        GIT_TAG stable
+)
+FetchContent_MakeAvailable(libyuv)
+
+## cgif
+FetchContent_Declare(
+        cgif
+        GIT_REPOSITORY https://github.com/dloebl/cgif.git
+        GIT_TAG 4ddc417
+)
+FetchContent_MakeAvailable(cgif)
+
+## giflib (only to encode)
+FetchContent_Declare(
+        giflib
+        GIT_REPOSITORY https://git.code.sf.net/p/giflib/code
+        GIT_TAG 5.2.2
+)
+FetchContent_MakeAvailable(giflib)
+
+## EasyGifReader (on top of giflib for easier reading)
+FetchContent_Declare(
+        easy_gif_reader
+        GIT_REPOSITORY https://github.com/Chlumsky/EasyGifReader
+        GIT_TAG eaaa794
+)
+FetchContent_MakeAvailable(easy_gif_reader)
+
+
 set(SOURCES
         user_profile.cpp
         user_groups.cpp
@@ -44,6 +91,23 @@ set(SOURCES
         ed25519.cpp
         curve25519.cpp
         hash.cpp
+        attachments.cpp
+        webp_utils.cpp
+        gif_utils.cpp
+
+        ${cgif_SOURCE_DIR}/src/cgif.c
+        ${cgif_SOURCE_DIR}/src/cgif_rgb.c
+        ${cgif_SOURCE_DIR}/src/cgif_raw.c
+
+        ${giflib_SOURCE_DIR}/gifalloc.c
+        ${giflib_SOURCE_DIR}/gif_err.c
+        ${giflib_SOURCE_DIR}/dgif_lib.c
+        ${giflib_SOURCE_DIR}/egif_lib.c
+        ${giflib_SOURCE_DIR}/gif_hash.c
+        ${giflib_SOURCE_DIR}/gif_font.c
+        ${giflib_SOURCE_DIR}/openbsd-reallocarray.c
+
+        ${easy_gif_reader_SOURCE_DIR}/EasyGifReader.cpp
 )
 
 add_library( # Sets the name of the library.
@@ -53,6 +117,15 @@ add_library( # Sets the name of the library.
         # Provides a relative path to your source file(s).
         ${SOURCES})
 
+target_include_directories(session_util
+        PRIVATE
+            ${cgif_SOURCE_DIR}/inc
+            ${libyuv_SOURCE_DIR}/include
+            ${giflib_SOURCE_DIR}
+            ${easy_gif_reader_SOURCE_DIR}
+)
+
+
 # Searches for a specified prebuilt library and stores the path as a
 # variable. Because CMake includes system libraries in the search path by
 # default, you only need to specify the name of the public NDK library
@@ -78,4 +151,10 @@ target_link_libraries( # Specifies the target library.
         libsodium::sodium-internal
         # Links the target library to the log library
         # included in the NDK.
-        ${log-lib})
+        ${log-lib}
+        webp
+        libwebpmux
+        webpdemux
+        webpdecoder
+        yuv
+)

library/src/main/cpp/attachments.cpp

@@ -0,0 +1,79 @@
+#include <jni.h>
+#include <session/attachments.hpp>
+#include "jni_utils.h"
+
+using namespace session::attachment;
+using namespace jni_utils;
+
+extern "C"
+JNIEXPORT jlong JNICALL
+Java_network_loki_messenger_libsession_1util_encrypt_Attachments_encryptedSize(JNIEnv *env,
+                                                                               jobject thiz,
+                                                                               jlong plaintext_size) {
+    return encrypted_size(plaintext_size);
+}
+
+extern "C"
+JNIEXPORT jlong JNICALL
+Java_network_loki_messenger_libsession_1util_encrypt_Attachments_decryptedMaxSize(JNIEnv *env,
+                                                                                  jobject thiz,
+                                                                                  jlong ciphertext_size) {
+    auto s = decrypted_max_size(ciphertext_size);
+    if (s.has_value()) {
+        return *s;
+    } else {
+        env->ThrowNew(env->FindClass("java/lang/IllegalArgumentException"),
+                      "ciphertext_size too small to be a valid encrypted attachment");
+        return 0;
+    }
+}
+
+extern "C"
+JNIEXPORT jbyteArray JNICALL
+Java_network_loki_messenger_libsession_1util_encrypt_Attachments_encryptBytes(JNIEnv *env,
+                                                                              jobject thiz,
+                                                                              jbyteArray seed,
+                                                                              jbyteArray plaintext_in,
+                                                                              jint plaintext_in_offset,
+                                                                              jint plaintext_in_len,
+                                                                              jbyteArray cipher_out,
+                                                                              jint cipher_out_offset,
+                                                                              jint cipher_out_len,
+                                                                              jint domain) {
+    return run_catching_cxx_exception_or_throws<jbyteArray>(env, [=] {
+        auto key = encrypt(
+            JavaByteArrayRef(env, seed).get_as_bytes(),
+            JavaByteArrayRef(env, plaintext_in).get_as_bytes().subspan(plaintext_in_offset, plaintext_in_len),
+            static_cast<Domain>(domain),
+            JavaByteArrayRef(env, cipher_out).get_as_bytes().subspan(cipher_out_offset, cipher_out_len)
+        );
+
+
+        return util::bytes_from_span(env, std::span(reinterpret_cast<unsigned char *>(key.data()), key.size()));
+    });
+}
+
+extern "C"
+JNIEXPORT jlong JNICALL
+Java_network_loki_messenger_libsession_1util_encrypt_Attachments_decryptBytes(JNIEnv *env,
+                                                                              jobject thiz,
+                                                                              jbyteArray key,
+                                                                              jbyteArray cipher_in,
+                                                                              jint cipher_in_offset,
+                                                                              jint cipher_in_len,
+                                                                              jbyteArray plain_out,
+                                                                              jint plain_out_offset,
+                                                                              jint plain_out_len) {
+    return run_catching_cxx_exception_or_throws<jlong>(env, [=] {
+        JavaByteArrayRef key_ref(env, key);
+
+        return decrypt(
+                JavaByteArrayRef(env, cipher_in).get_as_bytes().subspan(cipher_in_offset, cipher_in_len),
+                std::span<std::byte, ENCRYPT_KEY_SIZE>(
+                        reinterpret_cast<std::byte *>(key_ref.get().data()),
+                        ENCRYPT_KEY_SIZE
+                ),
+                JavaByteArrayRef(env, plain_out).get_as_bytes().subspan(plain_out_offset, plain_out_len)
+        );
+    });
+}