diff --git a/tetheroffload/Android.bp b/tetheroffload/Android.bp
new file mode 100644
index 0000000..4b50f11
--- /dev/null
+++ b/tetheroffload/Android.bp
@@ -0,0 +1,5 @@
+// This is an autogenerated file, do not edit.
+subdirs = [
+    "config/1.0",
+    "control/1.0",
+]
diff --git a/tetheroffload/config/1.0/Android.bp b/tetheroffload/config/1.0/Android.bp
new file mode 100644
index 0000000..7eac6b0
--- /dev/null
+++ b/tetheroffload/config/1.0/Android.bp
@@ -0,0 +1,60 @@
+// This file is autogenerated by hidl-gen. Do not edit manually.
+
+filegroup {
+    name: "android.hardware.tetheroffload.config@1.0_hal",
+    srcs: [
+        "IOffloadConfig.hal",
+    ],
+}
+
+genrule {
+    name: "android.hardware.tetheroffload.config@1.0_genc++",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++ -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.tetheroffload.config@1.0",
+    srcs: [
+        ":android.hardware.tetheroffload.config@1.0_hal",
+    ],
+    out: [
+        "android/hardware/tetheroffload/config/1.0/OffloadConfigAll.cpp",
+    ],
+}
+
+genrule {
+    name: "android.hardware.tetheroffload.config@1.0_genc++_headers",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++ -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.tetheroffload.config@1.0",
+    srcs: [
+        ":android.hardware.tetheroffload.config@1.0_hal",
+    ],
+    out: [
+        "android/hardware/tetheroffload/config/1.0/IOffloadConfig.h",
+        "android/hardware/tetheroffload/config/1.0/IHwOffloadConfig.h",
+        "android/hardware/tetheroffload/config/1.0/BnHwOffloadConfig.h",
+        "android/hardware/tetheroffload/config/1.0/BpHwOffloadConfig.h",
+        "android/hardware/tetheroffload/config/1.0/BsOffloadConfig.h",
+    ],
+}
+
+cc_library_shared {
+    name: "android.hardware.tetheroffload.config@1.0",
+    generated_sources: ["android.hardware.tetheroffload.config@1.0_genc++"],
+    generated_headers: ["android.hardware.tetheroffload.config@1.0_genc++_headers"],
+    export_generated_headers: ["android.hardware.tetheroffload.config@1.0_genc++_headers"],
+    vendor_available: true,
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "liblog",
+        "libutils",
+        "libcutils",
+        "android.hidl.base@1.0",
+    ],
+    export_shared_lib_headers: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "libutils",
+        "android.hidl.base@1.0",
+    ],
+}
diff --git a/tetheroffload/config/1.0/IOffloadConfig.hal b/tetheroffload/config/1.0/IOffloadConfig.hal
new file mode 100644
index 0000000..4d285da
--- /dev/null
+++ b/tetheroffload/config/1.0/IOffloadConfig.hal
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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 android.hardware.tetheroffload.config@1.0;
+
+
+/**
+ * Interface used for configuring the hardware management process
+ */
+interface IOffloadConfig {
+  /**
+   * Provides bound netlink file descriptors for use in the management process
+   *
+   * @param fd1   A file descriptor bound to the following netlink groups
+   *              (NF_NETLINK_CONNTRACK_NEW | NF_NETLINK_CONNTRACK_DESTROY).
+   * @param fd2   A file descriptor bound to the following netlink groups
+   *              (NF_NETLINK_CONNTRACK_UPDATE | NF_NETLINK_CONNTRACK_DESTROY).
+   *
+   * @return success true if successful, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   */
+  setHandles(handle fd1, handle fd2) generates (bool success, string errMsg);
+};
diff --git a/tetheroffload/control/1.0/Android.bp b/tetheroffload/control/1.0/Android.bp
new file mode 100644
index 0000000..1d94ec8
--- /dev/null
+++ b/tetheroffload/control/1.0/Android.bp
@@ -0,0 +1,71 @@
+// This file is autogenerated by hidl-gen. Do not edit manually.
+
+filegroup {
+    name: "android.hardware.tetheroffload.control@1.0_hal",
+    srcs: [
+        "types.hal",
+        "IOffloadControl.hal",
+        "ITetheringOffloadCallback.hal",
+    ],
+}
+
+genrule {
+    name: "android.hardware.tetheroffload.control@1.0_genc++",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++ -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.tetheroffload.control@1.0",
+    srcs: [
+        ":android.hardware.tetheroffload.control@1.0_hal",
+    ],
+    out: [
+        "android/hardware/tetheroffload/control/1.0/types.cpp",
+        "android/hardware/tetheroffload/control/1.0/OffloadControlAll.cpp",
+        "android/hardware/tetheroffload/control/1.0/TetheringOffloadCallbackAll.cpp",
+    ],
+}
+
+genrule {
+    name: "android.hardware.tetheroffload.control@1.0_genc++_headers",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++ -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.tetheroffload.control@1.0",
+    srcs: [
+        ":android.hardware.tetheroffload.control@1.0_hal",
+    ],
+    out: [
+        "android/hardware/tetheroffload/control/1.0/types.h",
+        "android/hardware/tetheroffload/control/1.0/hwtypes.h",
+        "android/hardware/tetheroffload/control/1.0/IOffloadControl.h",
+        "android/hardware/tetheroffload/control/1.0/IHwOffloadControl.h",
+        "android/hardware/tetheroffload/control/1.0/BnHwOffloadControl.h",
+        "android/hardware/tetheroffload/control/1.0/BpHwOffloadControl.h",
+        "android/hardware/tetheroffload/control/1.0/BsOffloadControl.h",
+        "android/hardware/tetheroffload/control/1.0/ITetheringOffloadCallback.h",
+        "android/hardware/tetheroffload/control/1.0/IHwTetheringOffloadCallback.h",
+        "android/hardware/tetheroffload/control/1.0/BnHwTetheringOffloadCallback.h",
+        "android/hardware/tetheroffload/control/1.0/BpHwTetheringOffloadCallback.h",
+        "android/hardware/tetheroffload/control/1.0/BsTetheringOffloadCallback.h",
+    ],
+}
+
+cc_library_shared {
+    name: "android.hardware.tetheroffload.control@1.0",
+    generated_sources: ["android.hardware.tetheroffload.control@1.0_genc++"],
+    generated_headers: ["android.hardware.tetheroffload.control@1.0_genc++_headers"],
+    export_generated_headers: ["android.hardware.tetheroffload.control@1.0_genc++_headers"],
+    vendor_available: true,
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "liblog",
+        "libutils",
+        "libcutils",
+        "android.hidl.base@1.0",
+    ],
+    export_shared_lib_headers: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "libutils",
+        "android.hidl.base@1.0",
+    ],
+}
diff --git a/tetheroffload/control/1.0/Android.mk b/tetheroffload/control/1.0/Android.mk
new file mode 100644
index 0000000..6e52c87
--- /dev/null
+++ b/tetheroffload/control/1.0/Android.mk
@@ -0,0 +1,274 @@
+# This file is autogenerated by hidl-gen. Do not edit manually.
+
+LOCAL_PATH := $(call my-dir)
+
+################################################################################
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := android.hardware.tetheroffload.control-V1.0-java
+LOCAL_MODULE_CLASS := JAVA_LIBRARIES
+
+intermediates := $(call local-generated-sources-dir, COMMON)
+
+HIDL := $(HOST_OUT_EXECUTABLES)/hidl-gen$(HOST_EXECUTABLE_SUFFIX)
+
+LOCAL_JAVA_LIBRARIES := \
+    android.hidl.base-V1.0-java \
+
+
+#
+# Build types.hal (IPv4AddrPortPair)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/IPv4AddrPortPair.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.IPv4AddrPortPair
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (NatTimeoutUpdate)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/NatTimeoutUpdate.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.NatTimeoutUpdate
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (NetworkProtocol)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/NetworkProtocol.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.NetworkProtocol
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (OffloadCallbackEvent)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/OffloadCallbackEvent.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.OffloadCallbackEvent
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build IOffloadControl.hal
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/IOffloadControl.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/IOffloadControl.hal
+$(GEN): PRIVATE_DEPS += $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::IOffloadControl
+
+$(GEN): $(LOCAL_PATH)/IOffloadControl.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build ITetheringOffloadCallback.hal
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/ITetheringOffloadCallback.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): PRIVATE_DEPS += $(LOCAL_PATH)/types.hal
+$(GEN): $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::ITetheringOffloadCallback
+
+$(GEN): $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+include $(BUILD_JAVA_LIBRARY)
+
+
+################################################################################
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := android.hardware.tetheroffload.control-V1.0-java-static
+LOCAL_MODULE_CLASS := JAVA_LIBRARIES
+
+intermediates := $(call local-generated-sources-dir, COMMON)
+
+HIDL := $(HOST_OUT_EXECUTABLES)/hidl-gen$(HOST_EXECUTABLE_SUFFIX)
+
+LOCAL_STATIC_JAVA_LIBRARIES := \
+    android.hidl.base-V1.0-java-static \
+
+
+#
+# Build types.hal (IPv4AddrPortPair)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/IPv4AddrPortPair.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.IPv4AddrPortPair
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (NatTimeoutUpdate)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/NatTimeoutUpdate.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.NatTimeoutUpdate
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (NetworkProtocol)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/NetworkProtocol.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.NetworkProtocol
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build types.hal (OffloadCallbackEvent)
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/OffloadCallbackEvent.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::types.OffloadCallbackEvent
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build IOffloadControl.hal
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/IOffloadControl.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/IOffloadControl.hal
+$(GEN): PRIVATE_DEPS += $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::IOffloadControl
+
+$(GEN): $(LOCAL_PATH)/IOffloadControl.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
+# Build ITetheringOffloadCallback.hal
+#
+GEN := $(intermediates)/android/hardware/tetheroffload/control/V1_0/ITetheringOffloadCallback.java
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+$(GEN): PRIVATE_DEPS += $(LOCAL_PATH)/types.hal
+$(GEN): $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+        $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+        -Ljava \
+        -randroid.hardware:hardware/interfaces \
+        -randroid.hidl:system/libhidl/transport \
+        android.hardware.tetheroffload.control@1.0::ITetheringOffloadCallback
+
+$(GEN): $(LOCAL_PATH)/ITetheringOffloadCallback.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+include $(BUILD_STATIC_JAVA_LIBRARY)
+
+
+
+include $(call all-makefiles-under,$(LOCAL_PATH))
diff --git a/tetheroffload/control/1.0/IOffloadControl.hal b/tetheroffload/control/1.0/IOffloadControl.hal
new file mode 100644
index 0000000..334f4ca
--- /dev/null
+++ b/tetheroffload/control/1.0/IOffloadControl.hal
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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 android.hardware.tetheroffload.control@1.0;
+
+import ITetheringOffloadCallback;
+
+
+/**
+ * Interface used to control the lifecycle of tethering offload
+ */
+interface IOffloadControl {
+  /**
+   * Indicates intent to start offload for tethering in immediate future.
+   *
+   * This API must be called exactly once the first time that Tethering is requested by
+   * the user.
+   *
+   * If this API is called multiple times without first calling stopOffload, then the subsequent
+   * calls must fail without changing the state of the server.
+   *
+   * If for some reason, the hardware is currently unable to support offload, this call must fail.
+   *
+   * @param cb Assuming success, this callback must provide unsolicited updates of offload status.
+   *           It is assumed to be valid until stopOffload is called.
+   *
+   * @return success true if initialization is successful, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   *
+   * Remarks: Initializing offload does not imply that any upstreams or downstreams have yet been,
+   * or even will be, chosen.  This API is symmetrical with stopOffload.
+   */
+  @entry
+  @callflow(next={"*"})
+  initOffload(ITetheringOffloadCallback cb) generates (bool success, string errMsg);
+
+  /**
+   * Indicate desire to tear down all tethering offload.
+   *
+   * Called after tethering is no longer requested by the user. Any remaining offload must
+   * be subsequently torn down by the management process.  Upon success, the callback registered
+   * in initOffload must be released, and offload must be stopped.
+   *
+   * @return success true if offload is stopped, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   *
+   * Remarks: Statistics must be reset by this API.
+   */
+  @exit
+  stopOffload() generates (bool success, string errMsg);
+
+  /**
+   * Instruct management process not to forward traffic destined to or from the specified prefixes.
+   *
+   * This API may only be called after initOffload and before stopOffload.
+   *
+   * @param prefixes List containing fully specified prefixes. For e.g. 192.168.1.12/24
+                     or 2001:4860:0684:0:0:0:0:0:1002/64
+   *
+   * @return success true if success, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   *
+   * Remarks: This list overrides any previously specified list
+   */
+  setLocalPrefixes(vec<string> prefixes) generates (bool success, string errMsg);
+
+  /**
+   * Query offloaded traffic statistics forwarded to an upstream address.
+   *
+   * Return statistics that have transpired since the last query.  This would include
+   * statistics from all offloaded downstream tether interfaces that have been forwarded to this
+   * upstream interface.  After returning the statistics, the counters are reset to zero.
+   *
+   * Only offloaded statistics must be returned by this API, software stats must not be
+   * returned.
+   *
+   * @param upstream Upstream interface on which traffic exited/entered
+   *
+   * @return rxBytes values depicting the received bytes
+   * @return txBytes values depicting the transmitted bytes
+   */
+  getForwardedStats(string upstream) generates (uint64_t rxBytes, uint64_t txBytes);
+
+  /**
+   * Instruct hardware to stop forwarding traffic and send a callback after limit bytes have been
+   * transferred in either direction on this upstream interface.
+   *
+   * The limit must be applied to all traffic on the given upstream interface.  This
+   * includes hardware forwarded traffic, software forwarded traffic, and AP-originated traffic.
+   * IPv4 and IPv6 traffic both count towards the same limit.  IP headers are included in the
+   * byte count limit, but, link-layer headers are not.
+   *
+   * This API may only be called while offload is occurring on this upstream.  The hardware
+   * management process is not expected to cache the value and apply the quota once offload is
+   * started.  This cache is not expected, because the limit value would likely become stale over
+   * time and would not reflect any new traffic that has occurred.
+   *
+   * This limit must replace any previous limit.  It may be interpreted as "tell me when
+   * <limit> bytes have been transferred (in either direction) on <upstream>, starting
+   * now and counting from zero."
+   *
+   * Once the limit is reached, the callback registered in initOffload must be called to indicate
+   * this event and all offload must be stopped.  If offload is desired again, the hardware
+   * management process must be completely reprogrammed by calling setUpstreamParameters and
+   * addDownstream again.  Note that it is not necessary to call initOffload again to resume offload
+   * if stopOffload was not called by the client.
+   *
+   * @param upstream Upstream interface name that limit must apply to
+   * @param limit    Bytes limit that can occur before action must be taken
+   *
+   * @return success true if limit is applied, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   */
+  setDataLimit(string upstream, uint64_t limit) generates (bool success, string errMsg);
+
+  /**
+   * Instruct hardware to start forwarding traffic to the specified upstream.
+   *
+   * When iface, v4Addr, and v4Gw are all non-null, the management process may begin forwarding
+   * any currently configured or future configured IPv4 downstreams to this upstream interface.
+   *
+   * If any of the previously three mentioned parameters are null, then any current IPv4 offload
+   * must be stopped.
+   *
+   * When iface and v6Gws are both non-null, and in the case of v6Gws, are not empty, the
+   * management process may begin forwarding any currently configured or future configured IPv6
+   * downstreams to this upstream interface.
+   *
+   * If either of the two above parameters are null, or no V6 Gateways are provided, then IPv6
+   * offload must be stopped.
+   *
+   * This API may only be called after initOffload and before stopOffload.
+   *
+   * @param iface  Upstream interface name.  Note that only one is needed because IPv4 and IPv6
+   *               interfaces cannot be different (only known that this can occur during software
+   *               xlat, which cannot be offloaded through hardware anyways).  If the iface is
+   *               null, offload must be stopped.
+   * @param v4Addr The local IPv4 address assigned to the provided upstream interface, i.e. the
+   *               IPv4 address the packets are NATed to. For e.g. 192.168.1.12.
+   * @param v4Gw   The IPv4 address of the IPv4 gateway on the upstream interface.
+   *               For e.g. 192.168.1.1
+   * @param v6Gws  A list of IPv6 addresses (for e.g. 2001:4860:0684:0:0:0:0:0:1002) for possible
+   *               IPv6 gateways on the upstream interface.
+   *
+   * @return success true if success, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   *
+   * Remarks: This overrides any previously configured parameters.
+   */
+  setUpstreamParameters(string iface, string v4Addr, string v4Gw, vec<string> v6Gws)
+          generates (bool success, string errMsg);
+
+  /**
+   * Configure a downstream interface and prefix in the hardware management process that may be
+   * forwarded.
+   *
+   * The prefix may be an IPv4 or an IPv6 address to signify which family can be offloaded from the
+   * specified tether interface.  The list of IPv4 and IPv6 downstreams that are configured may
+   * differ.
+   *
+   * If the given protocol, as determined by the prefix, has an upstream set,
+   * the hardware may begin forwarding traffic between the upstream and any devices on the
+   * downstream interface that have IP addresses within the specified prefix. Traffic from the same
+   * downstream interfaces is unaffected and must be forwarded if and only if it was already
+   * being forwarded.
+   *
+   * If no upstream is currently configured, then these downstream interface and prefixes must be
+   * preserved so that offload may begin in the future when an upstream is set.
+   *
+   * This API does not replace any previously configured downstreams and must be explictly removed
+   * by calling removeDownstream.
+   *
+   * This API may only be called after initOffload and before stopOffload.
+   *
+   * @param iface  Tether interface
+   * @param prefix Downstream prefix depicting addresses that may be offloaded.
+   *               For e.g. 192.168.1.12/24 or 2001:4860:0684::/64)
+   *
+   * @return success true if success, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   *
+   * Remarks: The hardware management process may fail this call in a normal situation.  This can
+   *          happen because the hardware cannot support the current number of prefixes, the
+   *          hardware cannot support concurrent offload on multiple interfaces, the hardware
+   *          cannot currently support offload on the tether interface for some reason, or any
+   *          other dynamic configuration issues which may occur.  In this case,
+   *          traffic must remain unaffected and must be forwarded if and only if it was already
+   *          being forwarded.
+   */
+  addDownstream(string iface, string prefix) generates (bool success, string errMsg);
+
+  /**
+   * Remove a downstream prefix that may be forwarded from the hardware management process.
+   *
+   * The prefix may be an IPv4 or an IPv6 address. If it was not previously configured using
+   * addDownstream, then this must be a no-op.
+   *
+   * This API may only be called after initOffload and before stopOffload.
+   *
+   * @param iface  Tether interface
+   * @param prefix Downstream prefix depicting address that must no longer be offloaded
+   *               For e.g. 192.168.1.12/24 or 2001:4860:0684::/64)
+   *
+   * @return success true if success, false otherwise
+   * @return errMsg a human readable string if eror has occured.
+   */
+  removeDownstream(string iface, string prefix) generates (bool success, string errMsg);
+};
diff --git a/tetheroffload/control/1.0/ITetheringOffloadCallback.hal b/tetheroffload/control/1.0/ITetheringOffloadCallback.hal
new file mode 100644
index 0000000..397667f
--- /dev/null
+++ b/tetheroffload/control/1.0/ITetheringOffloadCallback.hal
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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 android.hardware.tetheroffload.control@1.0;
+
+/**
+ * Callback providing information about status of hardware management process
+ * as well as providing a way to keep offloaded connections from timing out.
+ */
+interface ITetheringOffloadCallback {
+  /**
+   * Called when an asynchronous event is generated by the hardware management
+   * process.
+   */
+  oneway onEvent(OffloadCallbackEvent event);
+
+  /**
+   *  Provide a way for the management process to request that a connections
+   *  timeout be updated in kernel.
+   *
+   *  This is necessary to ensure that offloaded traffic is not cleaned up
+   *  by the kernel connection tracking module for IPv4.
+   */
+   oneway updateTimeout(NatTimeoutUpdate params);
+};
diff --git a/tetheroffload/control/1.0/types.hal b/tetheroffload/control/1.0/types.hal
new file mode 100644
index 0000000..e2576ac
--- /dev/null
+++ b/tetheroffload/control/1.0/types.hal
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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 android.hardware.tetheroffload.control@1.0;
+
+enum OffloadCallbackEvent : uint32_t {
+    /**
+     * Indicate that a working configuration has been programmed and the
+     * hardware management process has begun forwarding traffic.
+     */
+    OFFLOAD_STARTED = 1,
+    /**
+     * Indicate that an error has occurred which has disrupted hardware
+     * acceleration.  Software routing may still be attempted; however,
+     * statistics may be temporarily unavailable.  Statistics may be recovered
+     * after OFFLOAD_SUPPORT_AVAILABLE event is fired.
+     */
+    OFFLOAD_STOPPED_ERROR = 2,
+    /**
+     * Indicate that the device has moved to a RAT on which hardware
+     * acceleration is not supported.  Subsequent calls to setUpstreamParameters
+     * and add/removeDownstream will likely fail and cannot be presumed to be
+     * saved inside of the hardware management process.  Upon receiving
+     * OFFLOAD_SUPPORT_AVAIALBLE, the client may reprogram the hardware
+     * management process to begin offload again.
+     */
+    OFFLOAD_STOPPED_UNSUPPORTED = 3,
+    /**
+     * Indicate that the hardware management process is willing and able to
+     * provide support for hardware acceleration at this time.  If applicable,
+     * the client may query for statistics.  If offload is desired, the client
+     * must reprogram the hardware management process.
+     */
+    OFFLOAD_SUPPORT_AVAILABLE = 4,
+    /**
+     * Hardware acceleration is no longer in effect and must be reprogrammed
+     * in order to resume.  This event is fired when the limit, applied in
+     * setDataLimit, has expired.  It is recommended that the client query for
+     * statistics immediately after receiving this event.
+     */
+    OFFLOAD_STOPPED_LIMIT_REACHED = 5
+};
+
+enum NetworkProtocol : uint32_t {
+    TCP = 6,
+    UDP = 17
+};
+
+struct IPv4AddrPortPair {
+    /** IPv4 Address and Port */
+    string addr; // for e.g. 192.168.1.12
+    uint16_t port; // for e.g. 8080
+};
+
+struct NatTimeoutUpdate {
+    IPv4AddrPortPair src;
+    IPv4AddrPortPair dst;
+    NetworkProtocol proto;
+};