Merge "Implement fetching hardware address"

#pragma once

#include <linux/if_ether.h>

#include <array>

#include <optional>

#include <string>

namespace android::netdevice {

typedef std::array<uint8_t, ETH_ALEN> hwaddr_t;

/**

 * Configures libnetdevice to use PF_CAN sockets instead of AF_INET,

 * what requires less permissive SEPolicy rules for a given process.

 */

bool del(std::string dev);

/**

 * Fetches interface's hardware address.

 *

 * \param ifname Interface name

 * \return Hardware address (MAC address) or nullopt if the lookup failed

 */

std::optional<hwaddr_t> getHwAddr(const std::string& ifname);

}  // namespace android::netdevice

bool operator==(const android::netdevice::hwaddr_t lhs, const unsigned char rhs[ETH_ALEN]);

    return sock.send(req) && sock.receiveAck();

}

std::optional<hwaddr_t> getHwAddr(const std::string& ifname) {

    auto ifr = ifreqs::fromName(ifname);

    if (!ifreqs::send(SIOCGIFHWADDR, ifr)) return std::nullopt;

    hwaddr_t hwaddr;

    memcpy(hwaddr.data(), ifr.ifr_hwaddr.sa_data, hwaddr.size());

    return hwaddr;

}

}  // namespace android::netdevice

bool operator==(const android::netdevice::hwaddr_t lhs, const unsigned char rhs[ETH_ALEN]) {

    static_assert(lhs.size() == ETH_ALEN);

    return 0 == memcmp(lhs.data(), rhs, lhs.size());

}