+int dhcp_network_bind_raw_socket(int index, union sockaddr_union *link);
+int dhcp_network_bind_udp_socket(int index, be32_t client_address);
+int dhcp_network_send_raw_socket(int s, const union sockaddr_union *link,
+ const void *packet, size_t len);
+int dhcp_network_send_udp_socket(int s, be32_t server_address,
+ const void *packet, size_t len);