get ip from mac address

get_ip_from_mac.cpp

#include <string>
#include <iostream>

extern "C" {
	#include <netlink/cli/utils.h>
	#include <netlink/cli/neigh.h>
	#include <netlink/cli/link.h>
}

std::string get_ip_from_mac(std::string mac)
{
	struct nl_sock *sock;
	struct rtnl_neigh *neigh;
	struct nl_cache *neigh_cache;
	struct nl_dump_params params;
	char buf[128] = {0};

	sock = nl_cli_alloc_socket();
	nl_cli_connect(sock, NETLINK_ROUTE);
	neigh_cache = nl_cli_neigh_alloc_cache(sock);
	neigh = nl_cli_neigh_alloc();

	nl_cli_neigh_parse_lladdr(neigh, (char*)mac.c_str());

	nl_cache_foreach_filter(neigh_cache, OBJ_CAST(neigh), [](struct nl_object *obj, void *arg) {
		struct rtnl_addr *addr = (struct rtnl_addr *) obj;
		char* buf = (char*)arg;

		nl_addr2str(rtnl_addr_get_local(addr), buf, 128);
	}, buf);

	rtnl_neigh_put(neigh);
	nl_cache_put(neigh_cache);
	nl_socket_free(sock);

	return buf;
}

int main(int argc, char *argv[])
{
	std::string ip = get_ip_from_mac("3e:85:e3:01:ea:87");
	
	if (ip == "")
		std::cout << "not found\n" << std::endl;
	else
		std::cout << ip << std::endl;
    
	return 0;
}