| /* libresolv interfaces for internal use across glibc. |
| Copyright (C) 2016-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef _RESOLV_INTERNAL_H |
| #define _RESOLV_INTERNAL_H 1 |
| |
| #include <resolv.h> |
| #include <stdbool.h> |
| |
| /* Resolver flags. Used for _flags in struct __res_state. */ |
| #define RES_F_VC 0x00000001 /* Socket is TCP. */ |
| #define RES_F_CONN 0x00000002 /* Socket is connected. */ |
| #define RES_F_EDNS0ERR 0x00000004 /* EDNS0 caused errors. */ |
| |
| |
| /* Internal version of RES_USE_INET6 which does not trigger a |
| deprecation warning. */ |
| #define DEPRECATED_RES_USE_INET6 0x00002000 |
| |
| static inline bool |
| res_use_inet6 (void) |
| { |
| return _res.options & DEPRECATED_RES_USE_INET6; |
| } |
| |
| enum |
| { |
| /* The advertized EDNS buffer size. The value 1200 is derived |
| from the IPv6 minimum MTU (1280 bytes) minus some arbitrary |
| space for tunneling overhead. If the DNS server does not react |
| to ICMP Fragmentation Needed But DF Set messages, this should |
| avoid all UDP fragments on current networks. Avoiding UDP |
| fragments is desirable because it prevents fragmentation-based |
| spoofing attacks because the randomness in a DNS packet is |
| concentrated in the first fragment (with the headers) and does |
| not protect subsequent fragments. */ |
| RESOLV_EDNS_BUFFER_SIZE = 1200, |
| }; |
| |
| struct resolv_context; |
| |
| /* Internal function for implementing res_nmkquery and res_mkquery. |
| Also used by __res_context_query. */ |
| int __res_context_mkquery (struct resolv_context *, int op, const char *dname, |
| int class, int type, const unsigned char *data, |
| unsigned char *buf, int buflen) attribute_hidden; |
| |
| /* Main resolver query function for use within glibc. */ |
| int __res_context_search (struct resolv_context *, const char *, int, int, |
| unsigned char *, int, unsigned char **, |
| unsigned char **, int *, int *, int *); |
| libresolv_hidden_proto (__res_context_search) |
| |
| /* Main resolver query function for use within glibc. */ |
| int __res_context_query (struct resolv_context *, const char *, int, int, |
| unsigned char *, int, unsigned char **, |
| unsigned char **, int *, int *, int *); |
| libresolv_hidden_proto (__res_context_query) |
| |
| /* Internal function used to implement the query and search |
| functions. */ |
| int __res_context_send (struct resolv_context *, const unsigned char *, int, |
| const unsigned char *, int, unsigned char *, |
| int, unsigned char **, unsigned char **, |
| int *, int *, int *) attribute_hidden; |
| |
| /* Internal function similar to res_hostalias. */ |
| const char *__res_context_hostalias (struct resolv_context *, |
| const char *, char *, size_t); |
| libresolv_hidden_proto (__res_context_hostalias); |
| |
| /* Add an OPT record to a DNS query. */ |
| int __res_nopt (struct resolv_context *, int n0, |
| unsigned char *buf, int buflen, int anslen) attribute_hidden; |
| |
| /* Convert from presentation format (which usually means ASCII |
| printable) to network format (which is usually some kind of binary |
| format). The input is in the range [SRC, SRC + SRCLEN). The |
| output is written to DST (which has to be 4 or 16 bytes long, |
| depending on AF). Return 0 for invalid input, 1 for success, -1 |
| for an invalid address family. */ |
| int __inet_pton_length (int af, const char *src, size_t srclen, void *); |
| libc_hidden_proto (__inet_pton_length) |
| |
| #endif /* _RESOLV_INTERNAL_H */ |
