src/neighbor.cpp

#include "neighbor.hpp"

#include "ethernet_interface.hpp"
#include "netlink.hpp"
#include "network_manager.hpp"
#include "util.hpp"

#include <linux/neighbour.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <net/if.h>
#include <sys/socket.h>
#include <sys/types.h>

#include <phosphor-logging/elog-errors.hpp>
#include <phosphor-logging/elog.hpp>
#include <stdexcept>
#include <stdplus/raw.hpp>
#include <string>
#include <string_view>
#include <utility>
#include <vector>
#include <xyz/openbmc_project/Common/error.hpp>

namespace phosphor
{
namespace network
{
namespace detail
{

void parseNeighbor(const NeighborFilter& filter, const nlmsghdr& hdr,
                   std::string_view msg, std::vector<NeighborInfo>& neighbors)
{
    if (hdr.nlmsg_type != RTM_NEWNEIGH)
    {
        throw std::runtime_error("Not a neighbor msg");
    }
    const auto& ndm = netlink::extractRtData<ndmsg>(msg);

    // Filter out neighbors we don't care about
    unsigned ifindex = ndm.ndm_ifindex;
    if (filter.interface != 0 && filter.interface != ifindex)
    {
        return;
    }
    if ((ndm.ndm_state & filter.state) == 0)
    {
        return;
    }

    // Build the neighbor info for our valid neighbor
    NeighborInfo neighbor;
    neighbor.interface = ifindex;
    neighbor.state = ndm.ndm_state;
    bool set_addr = false;
    while (!msg.empty())
    {
        auto [hdr, data] = netlink::extractRtAttr(msg);
        if (hdr.rta_type == NDA_LLADDR)
        {
            neighbor.mac = stdplus::raw::copyFrom<ether_addr>(data);
        }
        else if (hdr.rta_type == NDA_DST)
        {
            neighbor.address = addrFromBuf(ndm.ndm_family, data);
            set_addr = true;
        }
    }
    if (!set_addr)
    {
        throw std::runtime_error("Missing address");
    }
    neighbors.push_back(std::move(neighbor));
}

} // namespace detail

std::vector<NeighborInfo> getCurrentNeighbors(const NeighborFilter& filter)
{
    std::vector<NeighborInfo> neighbors;
    auto cb = [&filter, &neighbors](const nlmsghdr& hdr, std::string_view msg) {
        detail::parseNeighbor(filter, hdr, msg, neighbors);
    };
    ndmsg msg{};
    msg.ndm_ifindex = filter.interface;
    netlink::performRequest(NETLINK_ROUTE, RTM_GETNEIGH, NLM_F_DUMP, msg, cb);
    return neighbors;
}

static auto makeObjPath(std::string_view root, InAddrAny addr)
{
    auto ret = sdbusplus::message::object_path(std::string(root));
    ret /= std::to_string(addr);
    return ret;
}

Neighbor::Neighbor(sdbusplus::bus_t& bus, std::string_view objRoot,
                   EthernetInterface& parent, InAddrAny addr, ether_addr lladdr,
                   State state) :
    Neighbor(bus, makeObjPath(objRoot, addr), parent, addr, lladdr, state)
{
}

Neighbor::Neighbor(sdbusplus::bus_t& bus,
                   sdbusplus::message::object_path objPath,
                   EthernetInterface& parent, InAddrAny addr, ether_addr lladdr,
                   State state) :
    NeighborObj(bus, objPath.str.c_str(), NeighborObj::action::defer_emit),
    parent(parent), objPath(std::move(objPath))
{
    NeighborObj::ipAddress(std::to_string(addr));
    NeighborObj::macAddress(std::to_string(lladdr));
    NeighborObj::state(state);

    // Emit deferred signal.
    emit_object_added();
}

void Neighbor::delete_()
{
    auto& neighbors = parent.staticNeighbors;
    std::unique_ptr<Neighbor> ptr;
    for (auto it = neighbors.begin(); it != neighbors.end(); ++it)
    {
        if (it->second.get() == this)
        {
            ptr = std::move(it->second);
            neighbors.erase(it);
            break;
        }
    }

    parent.writeConfigurationFile();
    parent.manager.reloadConfigs();
}

using sdbusplus::xyz::openbmc_project::Common::Error::NotAllowed;
using REASON =
    phosphor::logging::xyz::openbmc_project::Common::NotAllowed::REASON;
using phosphor::logging::elog;

std::string Neighbor::ipAddress(std::string /*ipAddress*/)
{
    elog<NotAllowed>(REASON("Property update is not allowed"));
}

std::string Neighbor::macAddress(std::string /*macAddress*/)
{
    elog<NotAllowed>(REASON("Property update is not allowed"));
}

Neighbor::State Neighbor::state(State /*state*/)
{
    elog<NotAllowed>(REASON("Property update is not allowed"));
}

} // namespace network
} // namespace phosphor