diff --git a/include/hardware/gatekeeper.h b/include/hardware/gatekeeper.h
new file mode 100644
index 0000000..89d96b1
--- /dev/null
+++ b/include/hardware/gatekeeper.h
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#ifndef ANDROID_HARDWARE_GATEKEEPER_H
+#define ANDROID_HARDWARE_GATEKEEPER_H
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <hardware/hardware.h>
+
+__BEGIN_DECLS
+
+#define GATEKEEPER_HARDWARE_MODULE_ID "gatekeeper"
+
+#define GATEKEEPER_MODULE_API_VERSION_0_1 HARDWARE_MODULE_API_VERSION(0, 1)
+
+#define HARDWARE_GATEKEEPER "gatekeeper"
+
+struct gatekeeper_module {
+    /**
+     * Comon methods of the gatekeeper module. This *must* be the first member of
+     * gatekeeper_module as users of this structure will cast a hw_module_t to
+     * a gatekeeper_module pointer in the appropriate context.
+     */
+    hw_module_t common;
+};
+
+struct gatekeeper_device {
+    /**
+     * Common methods of the gatekeeper device. As above, this must be the first
+     * member of keymaster_device.
+     */
+    hw_device_t common;
+
+    /**
+     * Enrolls desired_password, which should be derived from a user selected pin or password,
+     * with the authentication factor private key used only for enrolling authentication
+     * factor data.
+     *
+     * If there was already a password enrolled, it should be provided in
+     * current_password_handle, along with the current password in current_password
+     * that should validate against current_password_handle.
+     *
+     * Parameters:
+     * - dev: pointer to gatekeeper_device acquired via calls to gatekeeper_open
+     * - uid: the Android user identifier
+     *
+     * - current_password_handle: the currently enrolled password handle the user
+     *   wants to replace. May be null if there's no currently enrolled password.
+     * - current_password_handle_length: the length in bytes of the buffer pointed
+     *   at by current_password_handle. Must be 0 if current_password_handle is NULL.
+     *
+     * - current_password: the user's current password in plain text. If presented,
+     *   it MUST verify against current_password_handle.
+     * - current_password_length: the size in bytes of the buffer pointed at by
+     *   current_password. Must be 0 if the current_password is NULL.
+     *
+     * - desired_password: the new password the user wishes to enroll in plain-text.
+     *   Cannot be NULL.
+     * - desired_password_length: the length in bytes of the buffer pointed at by
+     *   desired_password.
+     *
+     * - enrolled_password_handle: on success, a buffer will be allocated with the
+     *   new password handle referencing the password provided in desired_password.
+     *   This buffer can be used on subsequent calls to enroll or verify.
+     *   The caller is responsible for deallocating this buffer via a call to free()
+     * - enrolled_password_handle_length: pointer to the length in bytes of the buffer allocated
+     *   by this function and pointed to by *enrolled_password_handle_length.
+     *
+     * Returns: 0 on success or an error code less than 0 on error.
+     * On error, enrolled_password_handle will not be allocated.
+     */
+    int (*enroll)(const struct gatekeeper_device *dev, uint32_t uid,
+            const uint8_t *current_password_handle, uint32_t current_password_handle_length,
+            const uint8_t *current_password, uint32_t current_password_length,
+            const uint8_t *desired_password, uint32_t desired_password_length,
+            uint8_t **enrolled_password_handle, uint32_t *enrolled_password_handle_length);
+
+    /**
+     * Verifies provided_password matches enrolled_password_handle.
+     *
+     * Implementations of this module may retain the result of this call
+     * to attest to the recency of authentication.
+     *
+     * On success, writes the address of a verification token to auth_token,
+     * usable to attest password verification to other trusted services. Clients
+     * may pass NULL for this value.
+     *
+     * Parameters:
+     * - dev: pointer to gatekeeper_device acquired via calls to gatekeeper_open
+     * - uid: the Android user identifier
+     *
+     * - challenge: An optional challenge to authenticate against, or 0. Used when a separate
+     *              authenticator requests password verification, or for transactional
+     *              password authentication.
+     *
+     * - enrolled_password_handle: the currently enrolled password handle that the
+     *   user wishes to verify against.
+     * - enrolled_password_handle_length: the length in bytes of the buffer pointed
+     *   to by enrolled_password_handle
+     *
+     * - provided_password: the plaintext password to be verified against the
+     *   enrolled_password_handle
+     * - provided_password_length: the length in bytes of the buffer pointed to by
+     *   provided_password
+     *
+     * - auth_token: on success, a buffer containing the authentication token
+     *   resulting from this verification is assigned to *auth_token. The caller
+     *   is responsible for deallocating this memory via a call to free()
+     * - auth_token_length: on success, the length in bytes of the authentication
+     *   token assigned to *auth_token will be assigned to *auth_token_length
+     *
+     * Returns: 0 on success or an error code less than 0 on error
+     * On error, auth token will not be allocated
+     */
+    int (*verify)(const struct gatekeeper_device *dev, uint32_t uid, uint64_t challenge,
+            const uint8_t *enrolled_password_handle, uint32_t enrolled_password_handle_length,
+            const uint8_t *provided_password, uint32_t provided_password_length,
+            uint8_t **auth_token, uint32_t *auth_token_length);
+
+};
+typedef struct gatekeeper_device gatekeeper_device_t;
+
+static inline int gatekeeper_open(const struct hw_module_t *module,
+        gatekeeper_device_t **device) {
+    return module->methods->open(module, HARDWARE_GATEKEEPER,
+            (struct hw_device_t **) device);
+}
+
+static inline int gatekeeper_close(gatekeeper_device_t *device) {
+    return device->common.close(&device->common);
+}
+
+__END_DECLS
+
+#endif // ANDROID_HARDWARE_GATEKEEPER_H