server/Network.h

/*
 * 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.
 */

#pragma once

#include "NetdConstants.h"
#include "UidRanges.h"

#include <set>
#include <string>

namespace android::net {

// A Network represents a collection of interfaces participating as a single administrative unit.
class Network {
public:
    enum Type {
        DUMMY,
        LOCAL,
        PHYSICAL,
        VIRTUAL,
    };

    // You MUST ensure that no interfaces are still assigned to this network, say by calling
    // clearInterfaces(), before deleting it. This is because interface removal may fail. If we
    // automatically removed interfaces in the destructor, you wouldn't know if it failed.
    virtual ~Network();

    virtual Type getType() const = 0;
    unsigned getNetId() const;

    bool hasInterface(const std::string& interface) const;
    const std::set<std::string>& getInterfaces() const;

    // These return 0 on success or negative errno on failure.
    [[nodiscard]] virtual int addInterface(const std::string& interface) = 0;
    [[nodiscard]] virtual int removeInterface(const std::string& interface) = 0;
    [[nodiscard]] int clearInterfaces();

    std::string toString() const;
    bool appliesToUser(uid_t uid) const;
    [[nodiscard]] int addUsers(const UidRanges& uidRanges);
    [[nodiscard]] int removeUsers(const UidRanges& uidRanges);
    bool isSecure() const;
    bool isPhysical() { return getType() == PHYSICAL; }
    bool isVirtual() { return getType() == VIRTUAL; }

protected:
    explicit Network(unsigned netId, bool mSecure = false);

    const unsigned mNetId;
    std::set<std::string> mInterfaces;
    UidRanges mUidRanges;
    const bool mSecure;

private:
    enum Action {
        REMOVE,
        ADD,
    };
};

}  // namespace android::net