PF_RT_SRC
snl_add_msg_attr_rule_addr(nw, PF_RT_SRC, &r->src);
{ .type = PF_RT_SRC, .off = _OUT(r.src), .arg = &rule_addr_parser,.cb = snl_attr_get_nested },
{ .type = PF_RT_SRC, .off = _OUT(src), .arg = &rule_addr_parser,.cb = nlattr_get_nested },
nlattr_add_rule_addr(nw, PF_RT_SRC, &rule->src);