AIDL CAN HAL

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Bug: 170405615
Test: atest CanControllerAidlTest
Test: manually test slcan and socketcan hardware
Change-Id: I06bbb1379f4385e89757722c0276009b54cc7255
diff --git a/automotive/can/aidl/default/CanBusVirtual.cpp b/automotive/can/aidl/default/CanBusVirtual.cpp
new file mode 100644
index 0000000..28a1258
--- /dev/null
+++ b/automotive/can/aidl/default/CanBusVirtual.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2022, 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 "CanBusVirtual.h"
+
+#include <android-base/logging.h>
+#include <libnetdevice/libnetdevice.h>
+
+namespace aidl::android::hardware::automotive::can {
+
+using namespace ::android;
+
+CanBusVirtual::CanBusVirtual(const std::string& ifname) : CanBus(ifname) {}
+
+Result CanBusVirtual::preUp() {
+    if (netdevice::exists(mIfname)) return Result::OK;
+
+    LOG(DEBUG) << "Virtual interface " << mIfname << " doesn't exist, creating...";
+    mWasCreated = true;
+    if (!netdevice::add(mIfname, "vcan")) {
+        LOG(ERROR) << "Can't create vcan interface " << mIfname;
+        return Result::UNKNOWN_ERROR;
+    }
+
+    return Result::OK;
+}
+
+bool CanBusVirtual::postDown() {
+    if (mWasCreated) {
+        mWasCreated = false;
+        if (!netdevice::del(mIfname)) {
+            LOG(ERROR) << "Couldn't remove vcan interface " << mIfname;
+            return false;
+        }
+    }
+    return true;
+}
+
+}  // namespace aidl::android::hardware::automotive::can