1 #ifndef HEADER_CURL_HOSTIP_H 2 #define HEADER_CURL_HOSTIP_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) 1998 - 2020, 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 struct 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 enum resolve_t { 83 CURLRESOLV_TIMEDOUT = -2, 84 CURLRESOLV_ERROR = -1, 85 CURLRESOLV_RESOLVED = 0, 86 CURLRESOLV_PENDING = 1 87 }; 88 enum resolve_t Curl_resolv(struct connectdata *conn, 89 const char *hostname, 90 int port, 91 bool allowDOH, 92 struct Curl_dns_entry **dnsentry); 93 enum resolve_t Curl_resolv_timeout(struct connectdata *conn, 94 const char *hostname, int port, 95 struct Curl_dns_entry **dnsentry, 96 timediff_t timeoutms); 97 98 #ifdef CURLRES_IPV6 99 /* 100 * Curl_ipv6works() returns TRUE if IPv6 seems to work. 101 */ 102 bool Curl_ipv6works(struct connectdata *conn); 103 #else 104 #define Curl_ipv6works(x) FALSE 105 #endif 106 107 /* 108 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've 109 * been set and returns TRUE if they are OK. 110 */ 111 bool Curl_ipvalid(struct connectdata *conn); 112 113 114 /* 115 * Curl_getaddrinfo() is the generic low-level name resolve API within this 116 * source file. There are several versions of this function - for different 117 * name resolve layers (selected at build-time). They all take this same set 118 * of arguments 119 */ 120 struct Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn, 121 const char *hostname, 122 int port, 123 int *waitp); 124 125 126 /* unlock a previously resolved dns entry */ 127 void Curl_resolv_unlock(struct Curl_easy *data, 128 struct Curl_dns_entry *dns); 129 130 /* init a new dns cache and return success */ 131 int Curl_mk_dnscache(struct curl_hash *hash); 132 133 /* prune old entries from the DNS cache */ 134 void Curl_hostcache_prune(struct Curl_easy *data); 135 136 /* Return # of addresses in a Curl_addrinfo struct */ 137 int Curl_num_addresses(const struct Curl_addrinfo *addr); 138 139 #if defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO) 140 int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa, 141 GETNAMEINFO_TYPE_ARG2 salen, 142 char *host, GETNAMEINFO_TYPE_ARG46 hostlen, 143 char *serv, GETNAMEINFO_TYPE_ARG46 servlen, 144 GETNAMEINFO_TYPE_ARG7 flags, 145 int line, const char *source); 146 #endif 147 148 /* IPv4 threadsafe resolve function used for synch and asynch builds */ 149 struct Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port); 150 151 CURLcode Curl_once_resolved(struct connectdata *conn, bool *protocol_connect); 152 153 /* 154 * Curl_addrinfo_callback() is used when we build with any asynch specialty. 155 * Handles end of async request processing. Inserts ai into hostcache when 156 * status is CURL_ASYNC_SUCCESS. Twiddles fields in conn to indicate async 157 * request completed whether successful or failed. 158 */ 159 CURLcode Curl_addrinfo_callback(struct connectdata *conn, 160 int status, 161 struct Curl_addrinfo *ai); 162 163 /* 164 * Curl_printable_address() returns a printable version of the 1st address 165 * given in the 'ip' argument. The result will be stored in the buf that is 166 * bufsize bytes big. 167 */ 168 void Curl_printable_address(const struct Curl_addrinfo *ip, 169 char *buf, size_t bufsize); 170 171 /* 172 * Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache. 173 * 174 * Returns the Curl_dns_entry entry pointer or NULL if not in the cache. 175 * 176 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after 177 * use, or we'll leak memory! 178 */ 179 struct Curl_dns_entry * 180 Curl_fetch_addr(struct connectdata *conn, 181 const char *hostname, 182 int port); 183 184 /* 185 * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache. 186 * 187 * Returns the Curl_dns_entry entry pointer or NULL if the storage failed. 188 */ 189 struct Curl_dns_entry * 190 Curl_cache_addr(struct Curl_easy *data, struct Curl_addrinfo *addr, 191 const char *hostname, int port); 192 193 #ifndef INADDR_NONE 194 #define CURL_INADDR_NONE (in_addr_t) ~0 195 #else 196 #define CURL_INADDR_NONE INADDR_NONE 197 #endif 198 199 #ifdef HAVE_SIGSETJMP 200 /* Forward-declaration of variable defined in hostip.c. Beware this 201 * is a global and unique instance. This is used to store the return 202 * address that we can jump back to from inside a signal handler. 203 * This is not thread-safe stuff. 204 */ 205 extern sigjmp_buf curl_jmpenv; 206 #endif 207 208 /* 209 * Function provided by the resolver backend to set DNS servers to use. 210 */ 211 CURLcode Curl_set_dns_servers(struct Curl_easy *data, char *servers); 212 213 /* 214 * Function provided by the resolver backend to set 215 * outgoing interface to use for DNS requests 216 */ 217 CURLcode Curl_set_dns_interface(struct Curl_easy *data, 218 const char *interf); 219 220 /* 221 * Function provided by the resolver backend to set 222 * local IPv4 address to use as source address for DNS requests 223 */ 224 CURLcode Curl_set_dns_local_ip4(struct Curl_easy *data, 225 const char *local_ip4); 226 227 /* 228 * Function provided by the resolver backend to set 229 * local IPv6 address to use as source address for DNS requests 230 */ 231 CURLcode Curl_set_dns_local_ip6(struct Curl_easy *data, 232 const char *local_ip6); 233 234 /* 235 * Clean off entries from the cache 236 */ 237 void Curl_hostcache_clean(struct Curl_easy *data, struct curl_hash *hash); 238 239 /* 240 * Populate the cache with specified entries from CURLOPT_RESOLVE. 241 */ 242 CURLcode Curl_loadhostpairs(struct Curl_easy *data); 243 244 CURLcode Curl_resolv_check(struct connectdata *conn, 245 struct Curl_dns_entry **dns); 246 int Curl_resolv_getsock(struct connectdata *conn, 247 curl_socket_t *socks); 248 249 #endif /* HEADER_CURL_HOSTIP_H */ 250