[core][trusty] add gatekeeper module

Change-Id: I1559a719034a754788d2cfa9a05fa60f36583bbf
diff --git a/trusty/gatekeeper/Android.mk b/trusty/gatekeeper/Android.mk
new file mode 100644
index 0000000..13e9a09
--- /dev/null
+++ b/trusty/gatekeeper/Android.mk
@@ -0,0 +1,50 @@
+#
+# 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.
+#
+
+# WARNING: Everything listed here will be built on ALL platforms,
+# including x86, the emulator, and the SDK.  Modules must be uniquely
+# named (liblights.panda), and must build everywhere, or limit themselves
+# to only building on ARM if they include assembly. Individual makefiles
+# are responsible for having their own logic, for fine-grained control.
+
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+
+LOCAL_MODULE := gatekeeper.trusty
+
+LOCAL_MODULE_RELATIVE_PATH := hw
+
+LOCAL_SRC_FILES := \
+	module.cpp \
+	trusty_gatekeeper_ipc.c \
+	trusty_gatekeeper.cpp
+
+LOCAL_CLFAGS = -fvisibility=hidden -Wall -Werror
+
+LOCAL_SHARED_LIBRARIES := \
+	libgatekeeper \
+	liblog \
+	libcutils \
+	libtrusty
+
+LOCAL_MODULE_TAGS := optional
+
+# Symlink gatekeeper.trusty.so -> gatekeeper.<device>.so so libhardware can find it.
+LOCAL_POST_INSTALL_CMD = \
+    $(hide) ln -sf $(notdir $(LOCAL_INSTALLED_MODULE)) $(dir $(LOCAL_INSTALLED_MODULE))gatekeeper.$(TARGET_DEVICE).so
+
+include $(BUILD_SHARED_LIBRARY)
diff --git a/trusty/gatekeeper/gatekeeper_ipc.h b/trusty/gatekeeper/gatekeeper_ipc.h
new file mode 100644
index 0000000..b05dcd8
--- /dev/null
+++ b/trusty/gatekeeper/gatekeeper_ipc.h
@@ -0,0 +1,40 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+#define GATEKEEPER_PORT "com.android.trusty.gatekeeper"
+#define GATEKEEPER_MAX_BUFFER_LENGTH 1024
+
+enum gatekeeper_command {
+	GK_REQ_SHIFT = 1,
+	GK_RESP_BIT  = 1,
+
+	GK_ENROLL       = (0 << GK_REQ_SHIFT),
+	GK_VERIFY       = (1 << GK_REQ_SHIFT),
+};
+
+/**
+ * gatekeeper_message - Serial header for communicating with GK server
+ * @cmd: the command, one of ENROLL, VERIFY. Payload must be a serialized
+ *       buffer of the corresponding request object.
+ * @payload: start of the serialized command specific payload
+ */
+struct gatekeeper_message {
+    uint32_t cmd;
+    uint8_t payload[0];
+};
+
diff --git a/trusty/gatekeeper/module.cpp b/trusty/gatekeeper/module.cpp
new file mode 100644
index 0000000..0ee3c2f
--- /dev/null
+++ b/trusty/gatekeeper/module.cpp
@@ -0,0 +1,57 @@
+/*
+ * 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.
+ */
+
+#include <hardware/hardware.h>
+
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "trusty_gatekeeper.h"
+
+using gatekeeper::TrustyGateKeeperDevice;
+
+static int trusty_gatekeeper_open(const hw_module_t *module, const char *name,
+        hw_device_t **device) {
+
+    if (strcmp(name, HARDWARE_GATEKEEPER) != 0) {
+        return -EINVAL;
+    }
+
+    TrustyGateKeeperDevice *gatekeeper = new TrustyGateKeeperDevice(module);
+    if (gatekeeper == NULL) return -ENOMEM;
+    *device = gatekeeper->hw_device();
+
+    return 0;
+}
+
+static struct hw_module_methods_t gatekeeper_module_methods = {
+    .open = trusty_gatekeeper_open,
+};
+
+struct gatekeeper_module HAL_MODULE_INFO_SYM __attribute__((visibility("default"))) = {
+    .common = {
+        .tag = HARDWARE_MODULE_TAG,
+        .module_api_version = GATEKEEPER_MODULE_API_VERSION_0_1,
+        .hal_api_version = HARDWARE_HAL_API_VERSION,
+        .id = GATEKEEPER_HARDWARE_MODULE_ID,
+        .name = "Trusty GateKeeper HAL",
+        .author = "The Android Open Source Project",
+        .methods = &gatekeeper_module_methods,
+        .dso = 0,
+        .reserved = {}
+    },
+};
diff --git a/trusty/gatekeeper/trusty_gatekeeper.cpp b/trusty/gatekeeper/trusty_gatekeeper.cpp
new file mode 100644
index 0000000..d24f44f
--- /dev/null
+++ b/trusty/gatekeeper/trusty_gatekeeper.cpp
@@ -0,0 +1,230 @@
+/*
+ * 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.
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <assert.h>
+#include <type_traits>
+
+#include "trusty_gatekeeper.h"
+#include "trusty_gatekeeper_ipc.h"
+#include "gatekeeper_ipc.h"
+
+#define LOG_TAG "TrustyGateKeeper"
+#include <cutils/log.h>
+
+namespace gatekeeper {
+
+const uint32_t SEND_BUF_SIZE = 8192;
+const uint32_t RECV_BUF_SIZE = 8192;
+
+TrustyGateKeeperDevice::TrustyGateKeeperDevice(const hw_module_t *module) {
+#if __cplusplus >= 201103L || defined(__GXX_EXPERIMENTAL_CXX0X__)
+    static_assert(std::is_standard_layout<TrustyGateKeeperDevice>::value,
+                  "TrustyGateKeeperDevice must be standard layout");
+    static_assert(offsetof(TrustyGateKeeperDevice, device_) == 0,
+                  "device_ must be the first member of TrustyGateKeeperDevice");
+    static_assert(offsetof(TrustyGateKeeperDevice, device_.common) == 0,
+                  "common must be the first member of gatekeeper_device");
+#else
+    assert(reinterpret_cast<gatekeeper_device_t *>(this) == &device_);
+    assert(reinterpret_cast<hw_device_t *>(this) == &(device_.common));
+#endif
+
+    memset(&device_, 0, sizeof(device_));
+    device_.common.tag = HARDWARE_DEVICE_TAG;
+    device_.common.version = 1;
+    device_.common.module = const_cast<hw_module_t *>(module);
+    device_.common.close = close_device;
+
+    device_.enroll = enroll;
+    device_.verify = verify;
+    device_.delete_user = nullptr;
+    device_.delete_all_users = nullptr;
+
+    int rc = trusty_gatekeeper_connect();
+    if (rc < 0) {
+        ALOGE("Error initializing trusty session: %d", rc);
+    }
+
+    error_ = rc;
+
+}
+
+hw_device_t* TrustyGateKeeperDevice::hw_device() {
+    return &device_.common;
+}
+
+int TrustyGateKeeperDevice::close_device(hw_device_t* dev) {
+    delete reinterpret_cast<TrustyGateKeeperDevice *>(dev);
+    return 0;
+}
+
+TrustyGateKeeperDevice::~TrustyGateKeeperDevice() {
+    trusty_gatekeeper_disconnect();
+}
+
+int TrustyGateKeeperDevice::Enroll(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) {
+
+    if (error_ != 0) {
+        return error_;
+    }
+
+    SizedBuffer desired_password_buffer(desired_password_length);
+    memcpy(desired_password_buffer.buffer.get(), desired_password, desired_password_length);
+
+    SizedBuffer current_password_handle_buffer(current_password_handle_length);
+    if (current_password_handle) {
+        memcpy(current_password_handle_buffer.buffer.get(), current_password_handle,
+                current_password_handle_length);
+    }
+
+    SizedBuffer current_password_buffer(current_password_length);
+    if (current_password) {
+        memcpy(current_password_buffer.buffer.get(), current_password, current_password_length);
+    }
+
+    EnrollRequest request(uid, &current_password_handle_buffer, &desired_password_buffer,
+            &current_password_buffer);
+    EnrollResponse response;
+
+    gatekeeper_error_t error = Send(request, &response);
+
+    if (error == ERROR_RETRY) {
+        return response.retry_timeout;
+    } else if (error != ERROR_NONE) {
+        return -EINVAL;
+    }
+
+    *enrolled_password_handle = response.enrolled_password_handle.buffer.release();
+    *enrolled_password_handle_length = response.enrolled_password_handle.length;
+
+
+    return 0;
+}
+
+int TrustyGateKeeperDevice::Verify(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, bool *request_reenroll) {
+    if (error_ != 0) {
+        return error_;
+    }
+
+    SizedBuffer password_handle_buffer(enrolled_password_handle_length);
+    memcpy(password_handle_buffer.buffer.get(), enrolled_password_handle,
+            enrolled_password_handle_length);
+    SizedBuffer provided_password_buffer(provided_password_length);
+    memcpy(provided_password_buffer.buffer.get(), provided_password, provided_password_length);
+
+    VerifyRequest request(uid, challenge, &password_handle_buffer, &provided_password_buffer);
+    VerifyResponse response;
+
+    gatekeeper_error_t error = Send(request, &response);
+
+    if (error == ERROR_RETRY) {
+        return response.retry_timeout;
+    } else if (error != ERROR_NONE) {
+        return -EINVAL;
+    }
+
+    if (auth_token != NULL && auth_token_length != NULL) {
+       *auth_token = response.auth_token.buffer.release();
+       *auth_token_length = response.auth_token.length;
+    }
+
+    if (request_reenroll != NULL) {
+        *request_reenroll = response.request_reenroll;
+    }
+
+    return 0;
+}
+
+gatekeeper_error_t TrustyGateKeeperDevice::Send(uint32_t command, const GateKeeperMessage& request,
+        GateKeeperMessage *response) {
+    uint32_t request_size = request.GetSerializedSize();
+    if (request_size > SEND_BUF_SIZE)
+        return ERROR_INVALID;
+    uint8_t send_buf[SEND_BUF_SIZE];
+    request.Serialize(send_buf, send_buf + request_size);
+
+    // Send it
+    uint8_t recv_buf[RECV_BUF_SIZE];
+    uint32_t response_size = RECV_BUF_SIZE;
+    int rc = trusty_gatekeeper_call(command, send_buf, request_size, recv_buf, &response_size);
+    if (rc < 0) {
+        ALOGE("error (%d) calling gatekeeper TA", rc);
+        return ERROR_INVALID;
+    }
+
+    const gatekeeper_message *msg = reinterpret_cast<gatekeeper_message *>(recv_buf);
+    const uint8_t *payload = msg->payload;
+
+    return response->Deserialize(payload, payload + response_size);
+}
+
+static inline TrustyGateKeeperDevice *convert_device(const gatekeeper_device *dev) {
+    return reinterpret_cast<TrustyGateKeeperDevice *>(const_cast<gatekeeper_device *>(dev));
+}
+
+/* static */
+int TrustyGateKeeperDevice::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) {
+
+    if (dev == NULL ||
+            enrolled_password_handle == NULL || enrolled_password_handle_length == NULL ||
+            desired_password == NULL || desired_password_length == 0)
+        return -EINVAL;
+
+    // Current password and current password handle go together
+    if (current_password_handle == NULL || current_password_handle_length == 0 ||
+            current_password == NULL || current_password_length == 0) {
+        current_password_handle = NULL;
+        current_password_handle_length = 0;
+        current_password = NULL;
+        current_password_length = 0;
+    }
+
+    return convert_device(dev)->Enroll(uid, current_password_handle, current_password_handle_length,
+            current_password, current_password_length, desired_password, desired_password_length,
+            enrolled_password_handle, enrolled_password_handle_length);
+
+}
+
+/* static */
+int TrustyGateKeeperDevice::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,
+        bool *request_reenroll) {
+
+    if (dev == NULL || enrolled_password_handle == NULL ||
+            provided_password == NULL) {
+        return -EINVAL;
+    }
+
+    return convert_device(dev)->Verify(uid, challenge, enrolled_password_handle,
+            enrolled_password_handle_length, provided_password, provided_password_length,
+            auth_token, auth_token_length, request_reenroll);
+}
+};
diff --git a/trusty/gatekeeper/trusty_gatekeeper.h b/trusty/gatekeeper/trusty_gatekeeper.h
new file mode 100644
index 0000000..82108dc
--- /dev/null
+++ b/trusty/gatekeeper/trusty_gatekeeper.h
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2014 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 TRUSTY_GATEKEEPER_H
+#define TRUSTY_GATEKEEPER_H
+
+#include <hardware/gatekeeper.h>
+#include <gatekeeper/gatekeeper_messages.h>
+
+#include "gatekeeper_ipc.h"
+
+namespace gatekeeper {
+
+class TrustyGateKeeperDevice {
+    public:
+
+    TrustyGateKeeperDevice(const hw_module_t* module);
+    ~TrustyGateKeeperDevice();
+
+    hw_device_t* hw_device();
+
+    /**
+     * Enrolls password_payload, which should be derived from a user selected pin or password,
+     * with the authentication factor private key used only for enrolling authentication
+     * factor data.
+     *
+     * Returns: 0 on success or an error code less than 0 on error.
+     * On error, enrolled_password will not be allocated.
+     */
+    int Enroll(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 expected_password after enrolling
+     * with the authentication factor private key.
+     *
+     * 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 verification_token,
+     *
+     * Returns: 0 on success or an error code less than 0 on error
+     * On error, verification token will not be allocated
+     */
+    int Verify(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,
+            bool *request_reenroll);
+
+    private:
+
+    gatekeeper_error_t Send(uint32_t command, const GateKeeperMessage& request,
+                           GateKeeperMessage* response);
+
+    gatekeeper_error_t Send(const EnrollRequest& request, EnrollResponse *response) {
+        return Send(GK_ENROLL, request, response);
+    }
+
+    gatekeeper_error_t Send(const VerifyRequest& request, VerifyResponse *response) {
+        return Send(GK_VERIFY, request, response);
+    }
+
+    // Static methods interfacing the HAL API with the TrustyGateKeeper device
+
+    /**
+     * 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.
+     */
+    static 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.
+     *
+     * Returns: 0 on success or an error code less than 0 on error
+     * On error, verification token will not be allocated
+     */
+    static 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, bool *request_reenroll);
+
+    static int close_device(hw_device_t* dev);
+
+    gatekeeper_device device_;
+    int error_;
+
+};
+}
+
+#endif
+
diff --git a/trusty/gatekeeper/trusty_gatekeeper_ipc.c b/trusty/gatekeeper/trusty_gatekeeper_ipc.c
new file mode 100644
index 0000000..a1c319e
--- /dev/null
+++ b/trusty/gatekeeper/trusty_gatekeeper_ipc.c
@@ -0,0 +1,91 @@
+/*
+ * 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.
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define LOG_TAG "TrustyGateKeeper"
+#include <cutils/log.h>
+#include <trusty/tipc.h>
+
+#include "trusty_gatekeeper_ipc.h"
+#include "gatekeeper_ipc.h"
+
+#define TRUSTY_DEVICE_NAME "/dev/trusty-ipc-dev0"
+
+static int handle_ = 0;
+
+int trusty_gatekeeper_connect() {
+    int rc = tipc_connect(TRUSTY_DEVICE_NAME, GATEKEEPER_PORT);
+    if (rc < 0) {
+        return rc;
+    }
+
+    handle_ = rc;
+    return 0;
+}
+
+int trusty_gatekeeper_call(uint32_t cmd, void *in, uint32_t in_size, uint8_t *out,
+                           uint32_t *out_size) {
+    if (handle_ == 0) {
+        ALOGE("not connected\n");
+        return -EINVAL;
+    }
+
+    size_t msg_size = in_size + sizeof(struct gatekeeper_message);
+    struct gatekeeper_message *msg = malloc(msg_size);
+    msg->cmd = cmd;
+    memcpy(msg->payload, in, in_size);
+
+    ssize_t rc = write(handle_, msg, msg_size);
+    free(msg);
+
+    if (rc < 0) {
+        ALOGE("failed to send cmd (%d) to %s: %s\n", cmd,
+                GATEKEEPER_PORT, strerror(errno));
+        return -errno;
+    }
+
+    rc = read(handle_, out, *out_size);
+    if (rc < 0) {
+        ALOGE("failed to retrieve response for cmd (%d) to %s: %s\n",
+                cmd, GATEKEEPER_PORT, strerror(errno));
+        return -errno;
+    }
+
+    if ((size_t) rc < sizeof(struct gatekeeper_message)) {
+        ALOGE("invalid response size (%d)\n", (int) rc);
+        return -EINVAL;
+    }
+
+    msg = (struct gatekeeper_message *) out;
+
+    if ((cmd | GK_RESP_BIT) != msg->cmd) {
+        ALOGE("invalid command (%d)\n", msg->cmd);
+        return -EINVAL;
+    }
+
+    *out_size = ((size_t) rc) - sizeof(struct gatekeeper_message);
+    return rc;
+}
+
+void trusty_gatekeeper_disconnect() {
+    if (handle_ != 0) {
+        tipc_close(handle_);
+    }
+}
+
diff --git a/trusty/gatekeeper/trusty_gatekeeper_ipc.h b/trusty/gatekeeper/trusty_gatekeeper_ipc.h
new file mode 100644
index 0000000..f8de7f8
--- /dev/null
+++ b/trusty/gatekeeper/trusty_gatekeeper_ipc.h
@@ -0,0 +1,24 @@
+/*
+ * 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.
+ */
+
+__BEGIN_DECLS
+
+int trusty_gatekeeper_connect();
+int trusty_gatekeeper_call(uint32_t cmd, void *in, uint32_t in_size, uint8_t *out,
+                           uint32_t *out_size);
+void trusty_gatekeeper_disconnect();
+
+__END_DECLS