int dhcpv6_init_ia(struct interface *iface, int socket);
size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
const struct sockaddr_in6 *addr, const void *data, const uint8_t *end);
int dhcpv6_init_ia(struct interface *iface, int socket);
size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
const struct sockaddr_in6 *addr, const void *data, const uint8_t *end);