Rename keyguard to gatekeeper

Avoids confusion with the other part of the system
known as Keyguard.

Change-Id: Ie32a3a4c990c4317cfd462a0e6dbf8fc490d4de2
diff --git a/include/hardware/gatekeeper.h b/include/hardware/gatekeeper.h
new file mode 100644
index 0000000..9150e70
--- /dev/null
+++ b/include/hardware/gatekeeper.h
@@ -0,0 +1,99 @@
+/*
+ * 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.
+     *
+     * 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, size_t current_password_handle_length,
+            const uint8_t *current_password, size_t current_password_length,
+            const uint8_t *desired_password, size_t desired_password_length,
+            uint8_t **enrolled_password_handle, size_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.
+     *
+     * Returns: 0 on success or an error code less than 0 on error
+     * On error, verification token will not be allocated
+     */
+    int (*verify)(const struct gatekeeper_device *dev, uint32_t uid,
+            const uint8_t *enrolled_password_handle, size_t enrolled_password_handle_length,
+            const uint8_t *provided_password, size_t provided_password_length,
+            uint8_t **auth_token, size_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