1 #ifndef HEADER_CURL_HOSTIP_H 2 #define HEADER_CURL_HOSTIP_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al. 11 * 12 * This software is licensed as described in the file COPYING, which 13 * you should have received as part of this distribution. The terms 14 * are also available at https://curl.haxx.se/docs/copyright.html. 15 * 16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 17 * copies of the Software, and permit persons to whom the Software is 18 * furnished to do so, under the terms of the COPYING file. 19 * 20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 21 * KIND, either express or implied. 22 * 23 ***************************************************************************/ 24 25 #include "curl_setup.h" 26 #include "hash.h" 27 #include "curl_addrinfo.h" 28 #include "timeval.h" /* for timediff_t */ 29 #include "asyn.h" 30 31 #ifdef HAVE_SETJMP_H 32 #include <setjmp.h> 33 #endif 34 35 #ifdef NETWARE 36 #undef in_addr_t 37 #define in_addr_t unsigned long 38 #endif 39 40 /* Allocate enough memory to hold the full name information structs and 41 * everything. OSF1 is known to require at least 8872 bytes. The buffer 42 * required for storing all possible aliases and IP numbers is according to 43 * Stevens' Unix Network Programming 2nd edition, p. 304: 8192 bytes! 44 */ 45 #define CURL_HOSTENT_SIZE 9000 46 47 #define CURL_TIMEOUT_RESOLVE 300 /* when using asynch methods, we allow this 48 many seconds for a name resolve */ 49 50 #define CURL_ASYNC_SUCCESS CURLE_OK 51 52 struct addrinfo; 53 struct hostent; 54 struct Curl_easy; 55 struct connectdata; 56 57 /* 58 * Curl_global_host_cache_init() initializes and sets up a global DNS cache. 59 * Global DNS cache is general badness. Do not use. This will be removed in 60 * a future version. Use the share interface instead! 61 * 62 * Returns a struct curl_hash pointer on success, NULL on failure. 63 */ 64 struct curl_hash *Curl_global_host_cache_init(void); 65 66 struct Curl_dns_entry { 67 Curl_addrinfo *addr; 68 /* timestamp == 0 -- CURLOPT_RESOLVE entry, doesn't timeout */ 69 time_t timestamp; 70 /* use-counter, use Curl_resolv_unlock to release reference */ 71 long inuse; 72 }; 73 74 /* 75 * Curl_resolv() returns an entry with the info for the specified host 76 * and port. 77 * 78 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after 79 * use, or we'll leak memory! 80 */ 81 /* return codes */ 82 #define CURLRESOLV_TIMEDOUT -2 83 #define CURLRESOLV_ERROR -1 84 #define CURLRESOLV_RESOLVED 0 85 #define CURLRESOLV_PENDING 1 86 int Curl_resolv(struct connectdata *conn, 87 const char *hostname, 88 int port, 89 bool allowDOH, 90 struct Curl_dns_entry **dnsentry); 91 int Curl_resolv_timeout(struct connectdata *conn, const char *hostname, 92 int port, struct Curl_dns_entry **dnsentry, 93 timediff_t timeoutms); 94 95 #ifdef CURLRES_IPV6 96 /* 97 * Curl_ipv6works() returns TRUE if IPv6 seems to work. 98 */ 99 bool Curl_ipv6works(void); 100 #else 101 #define Curl_ipv6works() FALSE 102 #endif 103 104 /* 105 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've 106 * been set and returns TRUE if they are OK. 107 */ 108 bool Curl_ipvalid(struct connectdata *conn); 109 110 111 /* 112 * Curl_getaddrinfo() is the generic low-level name resolve API within this 113 * source file. There are several versions of this function - for different 114 * name resolve layers (selected at build-time). They all take this same set 115 * of arguments 116 */ 117 Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, 118 const char *hostname, 119 int port, 120 int *waitp); 121 122 123 /* unlock a previously resolved dns entry */ 124 void Curl_resolv_unlock(struct Curl_easy *data, 125 struct Curl_dns_entry *dns); 126 127 /* init a new dns cache and return success */ 128 int Curl_mk_dnscache(struct curl_hash *hash); 129 130 /* prune old entries from the DNS cache */ 131 void Curl_hostcache_prune(struct Curl_easy *data); 132 133 /* Return # of addresses in a Curl_addrinfo struct */ 134 int Curl_num_addresses(const Curl_addrinfo *addr); 135 136 #if defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO) 137 int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa, 138 GETNAMEINFO_TYPE_ARG2 salen, 139 char *host, GETNAMEINFO_TYPE_ARG46 hostlen, 140 char *serv, GETNAMEINFO_TYPE_ARG46 servlen, 141 GETNAMEINFO_TYPE_ARG7 flags, 142 int line, const char *source); 143 #endif 144 145 /* IPv4 threadsafe resolve function used for synch and asynch builds */ 146 Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port); 147 148 CURLcode Curl_once_resolved(struct connectdata *conn, bool *protocol_connect); 149 150 /* 151 * Curl_addrinfo_callback() is used when we build with any asynch specialty. 152 * Handles end of async request processing. Inserts ai into hostcache when 153 * status is CURL_ASYNC_SUCCESS. Twiddles fields in conn to indicate async 154 * request completed whether successful or failed. 155 */ 156 CURLcode Curl_addrinfo_callback(struct connectdata *conn, 157 int status, 158 Curl_addrinfo *ai); 159 160 /* 161 * Curl_printable_address() returns a printable version of the 1st address 162 * given in the 'ip' argument. The result will be stored in the buf that is 163 * bufsize bytes big. 164 */ 165 const char *Curl_printable_address(const Curl_addrinfo *ip, 166 char *buf, size_t bufsize); 167 168 /* 169 * Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache. 170 * 171 * Returns the Curl_dns_entry entry pointer or NULL if not in the cache. 172 * 173 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after 174 * use, or we'll leak memory! 175 */ 176 struct Curl_dns_entry * 177 Curl_fetch_addr(struct connectdata *conn, 178 const char *hostname, 179 int port); 180 181 /* 182 * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache. 183 * 184 * Returns the Curl_dns_entry entry pointer or NULL if the storage failed. 185 */ 186 struct Curl_dns_entry * 187 Curl_cache_addr(struct Curl_easy *data, Curl_addrinfo *addr, 188 const char *hostname, int port); 189 190 #ifndef INADDR_NONE 191 #define CURL_INADDR_NONE (in_addr_t) ~0 192 #else 193 #define CURL_INADDR_NONE INADDR_NONE 194 #endif 195 196 #ifdef HAVE_SIGSETJMP 197 /* Forward-declaration of variable defined in hostip.c. Beware this 198 * is a global and unique instance. This is used to store the return 199 * address that we can jump back to from inside a signal handler. 200 * This is not thread-safe stuff. 201 */ 202 extern sigjmp_buf curl_jmpenv; 203 #endif 204 205 /* 206 * Function provided by the resolver backend to set DNS servers to use. 207 */ 208 CURLcode Curl_set_dns_servers(struct Curl_easy *data, char *servers); 209 210 /* 211 * Function provided by the resolver backend to set 212 * outgoing interface to use for DNS requests 213 */ 214 CURLcode Curl_set_dns_interface(struct Curl_easy *data, 215 const char *interf); 216 217 /* 218 * Function provided by the resolver backend to set 219 * local IPv4 address to use as source address for DNS requests 220 */ 221 CURLcode Curl_set_dns_local_ip4(struct Curl_easy *data, 222 const char *local_ip4); 223 224 /* 225 * Function provided by the resolver backend to set 226 * local IPv6 address to use as source address for DNS requests 227 */ 228 CURLcode Curl_set_dns_local_ip6(struct Curl_easy *data, 229 const char *local_ip6); 230 231 /* 232 * Clean off entries from the cache 233 */ 234 void Curl_hostcache_clean(struct Curl_easy *data, struct curl_hash *hash); 235 236 /* 237 * Populate the cache with specified entries from CURLOPT_RESOLVE. 238 */ 239 CURLcode Curl_loadhostpairs(struct Curl_easy *data); 240 241 CURLcode Curl_resolv_check(struct connectdata *conn, 242 struct Curl_dns_entry **dns); 243 int Curl_resolv_getsock(struct connectdata *conn, 244 curl_socket_t *socks); 245 246 #endif /* HEADER_CURL_HOSTIP_H */ 247