/* * Copyright (C) 2016 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef _RESOLV_PARAMS_H #define _RESOLV_PARAMS_H #include /* Hard-coded defines */ #define MAXNS 4 /* max # name servers we'll track */ #define MAXDNSRCH 6 /* max # domains in search path */ #define MAXDNSRCHPATH 256 /* max length of domain search paths */ #define MAXNSSAMPLES 64 /* max # samples to store per server */ /* Defaults used for initializing __res_params */ #define SUCCESS_THRESHOLD 75 /* if successes * 100 / total_samples is less than * this value, the server is considered failing */ #define NSSAMPLE_VALIDITY 1800 /* Sample validity in seconds. * Set to -1 to disable skipping failing * servers. */ /* If EDNS0_PADDING is defined, queries will be padded to a multiple of this length when EDNS0 is active. */ #define EDNS0_PADDING 128 /* per-netid configuration parameters passed from netd to the resolver */ struct __res_params { uint16_t sample_validity; // sample lifetime in s // threshold of success / total samples below which a server is considered broken uint8_t success_threshold; // 0: disable, value / 100 otherwise uint8_t min_samples; // min # samples needed for statistics to be considered meaningful uint8_t max_samples; // max # samples taken into account for statistics int base_timeout_msec; // base query retry timeout (if 0, use RES_TIMEOUT) }; typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error } res_sendhookact; typedef res_sendhookact (*res_send_qhook)(struct sockaddr * const *, const u_char **, int *, u_char *, int, int *); typedef res_sendhookact (*res_send_rhook)(const struct sockaddr *, const u_char *, int, u_char *, int, int *); #endif // _RESOLV_PARAMS_H