Native cryptography support using mbed TLS

native/src/main/c/jni_cipher.c

@@ -0,0 +1,81 @@
+#include <jni.h>
+#include <stdlib.h>
+#include <string.h>
+#include <mbedtls/aes.h>
+#include "jni_util.h"
+
+typedef unsigned char byte;
+
+typedef struct {
+    mbedtls_aes_context cipher;
+    byte *key;
+} velocity_cipher_context;
+
+JNIEXPORT jlong JNICALL
+Java_com_velocitypowered_natives_encryption_MbedtlsAesImpl_init(JNIEnv *env,
+    jobject obj,
+    jbyteArray key)
+{
+    velocity_cipher_context *ctx = malloc(sizeof(velocity_cipher_context));
+    if (ctx == NULL) {
+        throwException(env, "java/lang/OutOfMemoryError", "cipher allocate context");
+        return 0;
+    }
+
+    jsize keyLen = (*env)->GetArrayLength(env, key);
+    jbyte* keyBytes = (*env)->GetPrimitiveArrayCritical(env, key, NULL);
+    if (keyBytes == NULL) {
+        free(ctx);
+        throwException(env, "java/lang/OutOfMemoryError", "cipher get key");
+        return 0;
+    }
+
+    mbedtls_aes_init(&ctx->cipher);
+    int ret = mbedtls_aes_setkey_enc(&ctx->cipher, (byte*) keyBytes, keyLen * 8);
+    if (ret != 0) {
+        (*env)->ReleasePrimitiveArrayCritical(env, key, keyBytes, 0);
+        mbedtls_aes_free(&ctx->cipher);
+        free(ctx);
+
+        throwException(env, "java/security/GeneralSecurityException", "mbedtls set aes key");
+        return 0;
+    }
+
+    ctx->key = malloc(keyLen);
+    if (ctx->key == NULL) {
+        (*env)->ReleasePrimitiveArrayCritical(env, key, keyBytes, 0);
+        mbedtls_aes_free(&ctx->cipher);
+        free(ctx);
+
+        throwException(env, "java/lang/OutOfMemoryError", "cipher copy key");
+        return 0;
+    }
+    memcpy(ctx->key, keyBytes, keyLen);
+    (*env)->ReleasePrimitiveArrayCritical(env, key, keyBytes, 0);
+    return (jlong) ctx;
+}
+
+JNIEXPORT void JNICALL
+Java_com_velocitypowered_natives_encryption_MbedtlsAesImpl_free(JNIEnv *env,
+    jobject obj,
+    jlong ptr)
+{
+    velocity_cipher_context *ctx = (velocity_cipher_context*) ptr;
+    mbedtls_aes_free(&ctx->cipher);
+    free(ctx->key);
+    free(ctx);
+}
+
+JNIEXPORT void JNICALL
+Java_com_velocitypowered_natives_encryption_MbedtlsAesImpl_process(JNIEnv *env,
+    jobject obj,
+    jlong ptr,
+    jlong source,
+    jint len,
+    jlong dest,
+    jboolean encrypt)
+{
+    velocity_cipher_context *ctx = (velocity_cipher_context*) ptr;
+    mbedtls_aes_crypt_cfb8(&ctx->cipher, encrypt ? MBEDTLS_AES_ENCRYPT : MBEDTLS_AES_DECRYPT, len, ctx->key,
+        (byte*) source, (byte*) dest);
+}