Remove the VLAs in the JNI code so we don't get stack overflows when operating on large blobs

Also recompiled the libsodium AAR with the latest NDK (v29.0.14206865).

Author: arashpayan

.idea/deploymentTargetSelector.xml

@@ -8,10 +8,6 @@ project(georgenative)
 
 find_package(sodium REQUIRED CONFIG)
 
-# use a 16 KB page size
-set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
-set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,max-page-size=16384")
-
 # 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 it for you.
@@ -29,5 +25,5 @@ add_library( # Sets the name of the library.
              src/main/cpp/sodium.c)
 
 target_include_directories(native-lib PRIVATE)
-target_link_libraries(native-lib android sodium::sodium log)
+target_link_libraries(native-lib android sodium::sodium-minimal log)
 

app/CMakeLists.txt

@@ -12,8 +12,8 @@ android {
         compileSdk = 36
         minSdkVersion 29
         targetSdkVersion 36
-        versionCode 61
-        versionName "0.61"
+        versionCode 65
+        versionName "0.65"
         multiDexEnabled = true
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         resourceConfigurations += ['en', 'tr', 'ru']
@@ -78,7 +78,7 @@ android {
         sourceCompatibility JavaVersion.VERSION_11
         targetCompatibility JavaVersion.VERSION_11
     }
-    ndkVersion = '29.0.14033849'
+    ndkVersion = '29.0.14206865'
     namespace = 'xyz.zood.george'
     packagingOptions {
         jniLibs {

app/build.gradle

@@ -96,7 +96,11 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_symmetricKeyEncrypt(
     JNIEnv *env, jclass cls, jbyteArray msg, jbyteArray key) {
     unsigned long long msgLen = (unsigned long long)(*env)->GetArrayLength(env, msg);
     unsigned long long cipherTextLen = msgLen + crypto_secretbox_MACBYTES;
-    unsigned char cipherText[cipherTextLen];
+    unsigned char* cipherText = malloc(cipherTextLen);
+    if (cipherText == NULL) {
+        __android_log_print(ANDROID_LOG_ERROR, "ZoodLoc", "symmetricKeyEncrypt: failed to allocate cipherText");
+        return NULL;
+    }
     unsigned char* msgUChar = ucharArray(env, msg);
     unsigned char nonceUChar[crypto_secretbox_NONCEBYTES];
     unsigned char* keyUChar = ucharArray(env, key);
@@ -109,6 +113,7 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_symmetricKeyEncrypt(
     free(msgUChar);
     free(keyUChar);
     if (result != 0) {
+        free(cipherText);
         return NULL;
     }
 
@@ -124,6 +129,7 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_symmetricKeyEncrypt(
     jbyteArray nonceByteArray = byteArray(env, (unsigned char*)nonceUChar, crypto_secretbox_NONCEBYTES);
     (*env)->SetObjectField(env, skem, nonceFieldId, nonceByteArray);
 
+    free(cipherText);
     return skem;
 }
 
@@ -136,7 +142,11 @@ JNIEXPORT jbyteArray JNICALL Java_io_pijun_george_Sodium_symmetricKeyDecrypt(
         return NULL;
     }
 
-    unsigned char msgUChar[msgLen];
+    unsigned char* msgUChar = malloc(msgLen);
+    if (msgUChar == NULL) {
+        __android_log_print(ANDROID_LOG_ERROR, "ZoodLoc", "symmetricKeyDecrypt: failed to allocate msgUChar");
+        return NULL;
+    }
     unsigned char* cipherTextUChar = ucharArray(env, cipherText);
     unsigned char* nonceUChar = ucharArray(env, nonce);
     unsigned char* keyUChar = ucharArray(env, key);
@@ -150,10 +160,12 @@ JNIEXPORT jbyteArray JNICALL Java_io_pijun_george_Sodium_symmetricKeyDecrypt(
     free(keyUChar);
     if (result != 0) {
         __android_log_print(ANDROID_LOG_INFO, "ZoodLoc", "symmetricKeyDecrypt: non-zero result (%d)", result);
+        free(msgUChar);
         return NULL;
     }
 
     jbyteArray msg = byteArray(env, msgUChar, msgLen);
+    free(msgUChar);
     return msg;
 }
 
@@ -162,7 +174,11 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_publicKeyEncrypt(
     JNIEnv *env, jclass cls, jbyteArray msg, jbyteArray rcvrPubKey, jbyteArray sndrSecKey) {
     int msgLen = (*env)->GetArrayLength(env, msg);
     int cipherTextLen = crypto_box_MACBYTES + msgLen;
-    unsigned char cipherText[cipherTextLen];
+    unsigned char* cipherText = malloc(cipherTextLen);
+    if (cipherText == NULL) {
+        __android_log_print(ANDROID_LOG_ERROR, "ZoodLoc", "publicKeyEncrypt: failed to allocate cipherText");
+        return NULL;
+    }
     unsigned char nonce[crypto_box_NONCEBYTES];
     randombytes_buf(nonce, sizeof nonce);
     unsigned char* msgUChar = ucharArray(env, msg);
@@ -179,6 +195,7 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_publicKeyEncrypt(
     free(sndrKeyUChar);
     if (result != 0) {
         __android_log_print(ANDROID_LOG_INFO, "ZoodLoc", "publicKeyEncrypt: non-zero result (%d)", result);
+        free(cipherText);
         return NULL;
     }
 
@@ -194,6 +211,7 @@ JNIEXPORT jobject JNICALL Java_io_pijun_george_Sodium_publicKeyEncrypt(
     jbyteArray nonceByteArray = byteArray(env, nonce, sizeof nonce);
     (*env)->SetObjectField(env, skem, nonceFieldId, nonceByteArray);
 
+    free(cipherText);
     return skem;
 }
 
@@ -206,7 +224,11 @@ JNIEXPORT jbyteArray JNICALL Java_io_pijun_george_Sodium_publicKeyDecrypt(
         __android_log_print(ANDROID_LOG_INFO, "ZoodLoc", "publicKeyDecrypt: message is too short");
         return NULL;
     }
-    unsigned char msg[msgLen];
+    unsigned char* msg = malloc(msgLen);
+    if (msg == NULL) {
+        __android_log_print(ANDROID_LOG_ERROR, "ZoodLoc", "publicKeyDecrypt: failed to allocate msg");
+        return NULL;
+    }
     unsigned char* cipherTextUChar = ucharArray(env, cipherText);
     unsigned char* nonceUChar = ucharArray(env, nonce);
     unsigned char* pubKeyUChar = ucharArray(env, senderPubKey);
@@ -223,10 +245,13 @@ JNIEXPORT jbyteArray JNICALL Java_io_pijun_george_Sodium_publicKeyDecrypt(
     free(secKeyUChar);
     if (result != 0) {
         __android_log_print(ANDROID_LOG_INFO, "ZoodLoc", "publicKeyDecrypt: non-zero result (%d)", result);
+        free(msg);
         return NULL;
     }
 
-    return byteArray(env, msg, msgLen);
+    jbyteArray result_array = byteArray(env, msg, msgLen);
+    free(msg);
+    return result_array;
 }
 
 #pragma clang diagnostic pop

app/libs/libsodium-1.0.20.0.aar

@@ -15,7 +15,7 @@
 import java.util.Arrays;
 
 import io.pijun.george.api.DeviceInfo;
-import io.pijun.george.api.LimitedUserInfo;
+import io.pijun.george.api.LimitedUserInfoUnchecked;
 import io.pijun.george.api.Message;
 import io.pijun.george.api.MessageConverter;
 import io.pijun.george.api.OscarAPI;
@@ -109,7 +109,7 @@ public static Result decryptAndProcess(@NonNull Context context, @NonNull byte[]
             // we need to retrieve it from the server
             OscarAPI api = OscarClient.newInstance(token);
             try {
-                Response<LimitedUserInfo> response = api.getUser(Hex.toHexString(senderId)).execute();
+                Response<LimitedUserInfoUnchecked> response = api.getUser(Hex.toHexString(senderId)).execute();
                 if (!response.isSuccessful()) {
                     OscarError apiErr = OscarError.fromResponse(response);
                     if (apiErr == null) {
@@ -126,11 +126,16 @@ public static Result decryptAndProcess(@NonNull Context context, @NonNull byte[]
                             return Result.ErrorUnknown;
                     }
                 }
-                LimitedUserInfo lui = response.body();
-                if (lui == null) {
+                LimitedUserInfoUnchecked luiu = response.body();
+                if (luiu == null) {
                     L.w("Unable to decode user " + Hex.toHexString(senderId) + " from response");
                     return Result.ErrorUnknown;
                 }
+                var lui = luiu.toLimitedUserInfo();
+                if (lui == null) {
+                    L.w("Decoded user " + Hex.toHexString(senderId) + " had a null username or public key");
+                    return Result.ErrorUnknown;
+                }
                 // now that we've encountered a new user, add them to the database (because of TOFU)
                 user = db.addUser(senderId, lui.username, lui.publicKey);
                 L.i("  added user: " + user);

app/src/main/cpp/sodium.c

@@ -54,7 +54,7 @@ public interface OscarAPI {
     Call<ServerPublicKeyResponse> getServerPublicKey();
 
     @GET("users/{id}")
-    Call<LimitedUserInfo> getUser(@Path("id") String hexId);
+    Call<LimitedUserInfoUnchecked> getUser(@Path("id") String hexId);
 
     @GET("drop-boxes/{boxId}")
     Call<EncryptedData> pickUpPackage(@Path("boxId") String hexId);