1 /* $NetBSD: resolv.h,v 1.31 2005/12/26 19:01:47 perry Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1987, 1989 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 34 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 35 * 36 * Permission to use, copy, modify, and distribute this software for any 37 * purpose with or without fee is hereby granted, provided that the above 38 * copyright notice and this permission notice appear in all copies. 39 * 40 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 41 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 42 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 43 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 44 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 45 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 46 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 47 */ 48 49 /* 50 * @(#)resolv.h 8.1 (Berkeley) 6/2/93 51 * Id: resolv.h,v 1.7.2.11.4.2 2004/06/25 00:41:05 marka Exp 52 */ 53 54 #ifndef NETD_RESOLV_PRIVATE_H 55 #define NETD_RESOLV_PRIVATE_H 56 57 #include <android-base/logging.h> 58 #include <net/if.h> 59 #include <resolv.h> 60 #include <time.h> 61 #include <string> 62 63 #include "netd_resolv/params.h" 64 #include "netd_resolv/resolv.h" 65 #include "netd_resolv/stats.h" 66 #include "resolv_static.h" 67 68 // Linux defines MAXHOSTNAMELEN as 64, while the domain name limit in 69 // RFC 1034 and RFC 1035 is 255 octets. 70 #ifdef MAXHOSTNAMELEN 71 #undef MAXHOSTNAMELEN 72 #endif 73 #define MAXHOSTNAMELEN 256 74 75 /* 76 * Global defines and variables for resolver stub. 77 */ 78 #define MAXDFLSRCH 3 /* # default domain levels to try */ 79 #define LOCALDOMAINPARTS 2 /* min levels in name that is "local" */ 80 81 #define RES_TIMEOUT 5000 /* min. milliseconds between retries */ 82 #define MAXRESOLVSORT 10 /* number of net to sort on */ 83 #define RES_MAXNDOTS 15 /* should reflect bit field size */ 84 #define RES_DFLRETRY 2 /* Default #/tries. */ 85 #define RES_MAXTIME 65535 /* Infinity, in milliseconds. */ 86 87 struct res_state_ext; 88 89 struct __res_state { 90 unsigned netid; /* NetId: cache key and socket mark */ 91 u_long options; /* option flags - see below. */ 92 int nscount; /* number of name srvers */ 93 struct sockaddr_in nsaddr_list[MAXNS]; /* address of name server */ 94 #define nsaddr nsaddr_list[0] /* for backward compatibility */ 95 u_short id; /* current message id */ 96 char* dnsrch[MAXDNSRCH + 1]; /* components of domain to search */ 97 char defdname[256]; /* default domain (deprecated) */ 98 unsigned ndots : 4; /* threshold for initial abs. query */ 99 unsigned nsort : 4; /* number of elements in sort_list[] */ 100 char unused[3]; 101 struct { 102 struct in_addr addr; 103 uint32_t mask; 104 } sort_list[MAXRESOLVSORT]; 105 unsigned _mark; /* If non-0 SET_MARK to _mark on all request sockets */ 106 int _vcsock; /* PRIVATE: for res_send VC i/o */ 107 u_int _flags; /* PRIVATE: see below */ 108 u_int _pad; /* make _u 64 bit aligned */ 109 union { 110 /* On an 32-bit arch this means 512b total. */ 111 char pad[72 - 4 * sizeof(int) - 2 * sizeof(void*)]; 112 struct { 113 uint16_t nscount; 114 uint16_t nstimes[MAXNS]; /* ms. */ 115 int nssocks[MAXNS]; 116 struct res_state_ext* ext; /* extention for IPv6 */ 117 } _ext; 118 } _u; 119 struct res_static rstatic[1]; 120 bool use_local_nameserver; /* DNS-over-TLS bypass */ 121 }; 122 123 typedef struct __res_state* res_state; 124 125 /* Retrieve a local copy of the stats for the given netid. The buffer must have space for 126 * MAXNS __resolver_stats. Returns the revision id of the resolvers used. 127 */ 128 int resolv_cache_get_resolver_stats(unsigned netid, res_params* params, res_stats stats[MAXNS]); 129 130 /* Add a sample to the shared struct for the given netid and server, provided that the 131 * revision_id of the stored servers has not changed. 132 */ 133 void _resolv_cache_add_resolver_stats_sample(unsigned netid, int revision_id, int ns, 134 const res_sample* sample, int max_samples); 135 136 // Calculate the round-trip-time from start time t0 and end time t1. 137 int _res_stats_calculate_rtt(const timespec* t1, const timespec* t0); 138 139 // Create a sample for calculating server reachability statistics. 140 void _res_stats_set_sample(res_sample* sample, time_t now, int rcode, int rtt); 141 142 /* End of stats related definitions */ 143 144 // Flags for res_state->_flags 145 #define RES_F_VC 0x00000001 // socket is TCP 146 #define RES_F_EDNS0ERR 0x00000004 // EDNS0 caused errors 147 148 /* 149 * Resolver options (keep these in synch with res_debug.c, please) 150 */ 151 #define RES_INIT 0x00000001 /* address initialized */ 152 #define RES_DEBUG 0x00000002 /* print debug messages */ 153 #define RES_AAONLY 0x00000004 /* authoritative answers only (!IMPL)*/ 154 #define RES_USEVC 0x00000008 /* use virtual circuit */ 155 #define RES_PRIMARY 0x00000010 /* query primary server only (!IMPL) */ 156 #define RES_IGNTC 0x00000020 /* ignore trucation errors */ 157 #define RES_RECURSE 0x00000040 /* recursion desired */ 158 #define RES_DEFNAMES 0x00000080 /* use default domain name */ 159 #define RES_STAYOPEN 0x00000100 /* Keep TCP socket open */ 160 #define RES_DNSRCH 0x00000200 /* search up local domain tree */ 161 #define RES_INSECURE1 0x00000400 /* type 1 security disabled */ 162 #define RES_INSECURE2 0x00000800 /* type 2 security disabled */ 163 #define RES_USE_INET6 0x00002000 /* use/map IPv6 in gethostbyname() */ 164 #define RES_ROTATE 0x00004000 /* rotate ns list after each query */ 165 #define RES_NOCHECKNAME 0x00008000 /* do not check names for sanity. */ 166 #define RES_KEEPTSIG 0x00010000 /* do not strip TSIG records */ 167 #define RES_BLAST 0x00020000 /* blast all recursive servers */ 168 #define RES_NOTLDQUERY 0x00100000 /* don't unqualified name as a tld */ 169 #define RES_USE_DNSSEC 0x00200000 /* use DNSSEC using OK bit in OPT */ 170 /* #define RES_DEBUG2 0x00400000 */ /* nslookup internal */ 171 /* KAME extensions: use higher bit to avoid conflict with ISC use */ 172 #define RES_USE_DNAME 0x10000000 /* use DNAME */ 173 #define RES_USE_EDNS0 0x40000000 /* use EDNS0 if configured */ 174 #define RES_NO_NIBBLE2 0x80000000 /* disable alternate nibble lookup */ 175 176 #define RES_DEFAULT (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH | RES_NO_NIBBLE2) 177 178 179 /* 180 * Error code extending h_errno codes defined in bionic/libc/include/netdb.h. 181 * 182 * This error code, including legacy h_errno, is returned from res_nquery(), res_nsearch(), 183 * res_nquerydomain(), res_queryN(), res_searchN() and res_querydomainN() for DNS metrics. 184 * 185 * TODO: Consider mapping legacy and extended h_errno into a unified resolver error code mapping. 186 */ 187 #define NETD_RESOLV_H_ERRNO_EXT_TIMEOUT RCODE_TIMEOUT 188 189 extern const char* const _res_opcodes[]; 190 191 /* Things involving an internal (static) resolver context. */ 192 struct __res_state* res_get_state(void); 193 194 int res_hnok(const char*); 195 int res_ownok(const char*); 196 int res_mailok(const char*); 197 int res_dnok(const char*); 198 int dn_skipname(const u_char*, const u_char*); 199 void putlong(uint32_t, u_char*); 200 void putshort(uint16_t, u_char*); 201 202 // Thread-unsafe functions returning pointers to static buffers :-( 203 // TODO: switch all res_debug to std::string 204 const char* p_class(int); 205 const char* p_type(int); 206 const char* p_rcode(int); 207 const char* p_section(int, int); 208 209 int res_nameinquery(const char*, int, int, const u_char*, const u_char*); 210 int res_queriesmatch(const u_char*, const u_char*, const u_char*, const u_char*); 211 /* Things involving a resolver context. */ 212 int res_ninit(res_state); 213 void res_pquery(const u_char*, int); 214 215 int res_nquery(res_state, const char*, int, int, u_char*, int, int*); 216 int res_nsearch(res_state, const char*, int, int, u_char*, int, int*); 217 int res_nquerydomain(res_state, const char*, const char*, int, int, u_char*, int, int*); 218 int res_nmkquery(res_state, int, const char*, int, int, const u_char*, int, const u_char*, u_char*, 219 int); 220 int res_nsend(res_state, const u_char*, int, u_char*, int, int*, uint32_t); 221 void res_nclose(res_state); 222 int res_nopt(res_state, int, u_char*, int, int); 223 int res_vinit(res_state, int); 224 void res_ndestroy(res_state); 225 void res_setservers(res_state, const sockaddr_union*, int); 226 int res_getservers(res_state, sockaddr_union*, int); 227 228 struct android_net_context; /* forward */ 229 void res_setnetcontext(res_state, const struct android_net_context*); 230 231 int getaddrinfo_numeric(const char* hostname, const char* servname, addrinfo hints, 232 addrinfo** result); 233 234 // Helper function for converting h_errno to the error codes visible to netd 235 int herrnoToAiErrno(int herrno); 236 237 // switch resolver log severity 238 android::base::LogSeverity logSeverityStrToEnum(const std::string& logSeverityStr); 239 240 #endif // NETD_RESOLV_PRIVATE_H 241