1 files changed, 62 insertions, 0 deletions
diff --git a/nearby/presence/ldt_np_jni/java/LdtNpJni/src/main/java/com/google/android/gms/nearby/presence/hazmat/LdtNpJni.java b/nearby/presence/ldt_np_jni/java/LdtNpJni/src/main/java/com/google/android/gms/nearby/presence/hazmat/LdtNpJni.java
new file mode 100644
index 0000000..bbb0067
--- /dev/null
+++ b/nearby/presence/ldt_np_jni/java/LdtNpJni/src/main/java/com/google/android/gms/nearby/presence/hazmat/LdtNpJni.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2022 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.gms.nearby.presence.hazmat;
+
+/** JNI for LDT-XTS-AES128 with the "swap" mix function. */
+class LdtNpJni {
+
+  static {
+    System.loadLibrary("ldt_np_jni");
+  }
+
+  /**
+   * Create an instance of LDT-XTS-AES-128 using the Swap mix function.
+   *
+   * @param key key bytes, must be 4x AES key size = 64 bytes
+   * @return 0 on error, and any other value for success
+   */
+  static native long createLdtCipher(byte[] key_seed, byte[] metadata_key_hmac_tag);
+
+  /**
+   * Close the native resources for an Ldt instance.
+   *
+   * @param ldtHandle An ldt handle returned from {@link LdtNpJni#createLdtCipher}.
+   * @return 0 on success, <0 for any error
+   */
+  static native int closeLdtCipher(long ldtHandle);
+
+  /**
+   * Encrypt the data in place.
+   *
+   * @param ldtHandle An ldt handle returned from {@link LdtNpJni#createLdtCipher}.
+   * @param salt big-endian salt to be expanded into bytes XORd into the LDT tweaks
+   * @param data size must be between 16 and 31 bytes
+   * @return 0 on success, -1 if the data size is wrong, or another negative number for any other
+   *     error
+   */
+  static native int encrypt(long ldtHandle, char salt, byte[] data);
+
+  /**
+   * Decrypt the data in place using the default LDT tweak padding scheme.
+   *
+   * @param ldtHandle An ldt address returned from {@link LdtNpJni#createLdtCipher}.
+   * @param salt big-endian salt to be expanded into bytes XORd into the LDT tweaks
+   * @param data size must be between 16 and 31 bytes
+   * @return 0 on success, -1 if the data size is wrong, -2 if the calculated hmac
+   *     does not match the provided tag or another negative number for any other error
+   */
+  static native int decrypt_and_verify(long ldtHandle, char salt, byte[] data);
+}