#ifndef HEADER_CURL_HOSTIP_H #define HEADER_CURL_HOSTIP_H /*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * * SPDX-License-Identifier: curl * ***************************************************************************/ #include "curl_setup.h" #include "hash.h" #include "curl_addrinfo.h" #include "timeval.h" /* for timediff_t */ #include "asyn.h" #include #ifdef USE_HTTPSRR # include #endif /* Allocate enough memory to hold the full name information structs and * everything. OSF1 is known to require at least 8872 bytes. The buffer * required for storing all possible aliases and IP numbers is according to * Stevens' Unix Network Programming 2nd edition, p. 304: 8192 bytes! */ #define CURL_HOSTENT_SIZE 9000 #define CURL_TIMEOUT_RESOLVE 300 /* when using asynch methods, we allow this many seconds for a name resolve */ #define CURL_ASYNC_SUCCESS CURLE_OK struct addrinfo; struct hostent; struct Curl_easy; struct connectdata; /* * Curl_global_host_cache_init() initializes and sets up a global DNS cache. * Global DNS cache is general badness. Do not use. This will be removed in * a future version. Use the share interface instead! * * Returns a struct Curl_hash pointer on success, NULL on failure. */ struct Curl_hash *Curl_global_host_cache_init(void); #ifdef USE_HTTPSRR #define CURL_MAXLEN_host_name 253 struct Curl_https_rrinfo { size_t len; /* raw encoded length */ unsigned char *val; /* raw encoded octets */ /* * fields from HTTPS RR, with the mandatory fields * first (priority, target), then the others in the * order of the keytag numbers defined at * https://datatracker.ietf.org/doc/html/rfc9460#section-14.3.2 */ uint16_t priority; char *target; char *alpns; /* keytag = 1 */ bool no_def_alpn; /* keytag = 2 */ /* * we do not support ports (keytag = 3) as we do not support * port-switching yet */ unsigned char *ipv4hints; /* keytag = 4 */ size_t ipv4hints_len; unsigned char *echconfiglist; /* keytag = 5 */ size_t echconfiglist_len; unsigned char *ipv6hints; /* keytag = 6 */ size_t ipv6hints_len; }; #endif struct Curl_dns_entry { struct Curl_addrinfo *addr; #ifdef USE_HTTPSRR struct Curl_https_rrinfo *hinfo; #endif /* timestamp == 0 -- permanent CURLOPT_RESOLVE entry (does not time out) */ time_t timestamp; /* reference counter, entry is freed on reaching 0 */ size_t refcount; /* hostname port number that resolved to addr. */ int hostport; /* hostname that resolved to addr. may be NULL (Unix domain sockets). */ char hostname[1]; }; bool Curl_host_is_ipnum(const char *hostname); /* * Curl_resolv() returns an entry with the info for the specified host * and port. * * The returned data *MUST* be "released" with Curl_resolv_unlink() after * use, or we will leak memory! */ /* return codes */ enum resolve_t { CURLRESOLV_TIMEDOUT = -2, CURLRESOLV_ERROR = -1, CURLRESOLV_RESOLVED = 0, CURLRESOLV_PENDING = 1 }; enum resolve_t Curl_resolv(struct Curl_easy *data, const char *hostname, int port, bool allowDOH, struct Curl_dns_entry **dnsentry); enum resolve_t Curl_resolv_timeout(struct Curl_easy *data, const char *hostname, int port, struct Curl_dns_entry **dnsentry, timediff_t timeoutms); #ifdef USE_IPV6 /* * Curl_ipv6works() returns TRUE if IPv6 seems to work. */ bool Curl_ipv6works(struct Curl_easy *data); #else #define Curl_ipv6works(x) FALSE #endif /* * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've * been set and returns TRUE if they are OK. */ bool Curl_ipvalid(struct Curl_easy *data, struct connectdata *conn); /* * Curl_getaddrinfo() is the generic low-level name resolve API within this * source file. There are several versions of this function - for different * name resolve layers (selected at build-time). They all take this same set * of arguments */ struct Curl_addrinfo *Curl_getaddrinfo(struct Curl_easy *data, const char *hostname, int port, int *waitp); /* unlink a dns entry, potentially shared with a cache */ void Curl_resolv_unlink(struct Curl_easy *data, struct Curl_dns_entry **pdns); /* init a new dns cache */ void Curl_init_dnscache(struct Curl_hash *hash, size_t hashsize); /* prune old entries from the DNS cache */ void Curl_hostcache_prune(struct Curl_easy *data); /* IPv4 threadsafe resolve function used for synch and asynch builds */ struct Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port); CURLcode Curl_once_resolved(struct Curl_easy *data, bool *protocol_connect); /* * Curl_addrinfo_callback() is used when we build with any asynch specialty. * Handles end of async request processing. Inserts ai into hostcache when * status is CURL_ASYNC_SUCCESS. Twiddles fields in conn to indicate async * request completed whether successful or failed. */ CURLcode Curl_addrinfo_callback(struct Curl_easy *data, int status, struct Curl_addrinfo *ai); /* * Curl_printable_address() returns a printable version of the 1st address * given in the 'ip' argument. The result will be stored in the buf that is * bufsize bytes big. */ void Curl_printable_address(const struct Curl_addrinfo *ip, char *buf, size_t bufsize); /* * Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache. * * Returns the Curl_dns_entry entry pointer or NULL if not in the cache. * * The returned data *MUST* be "released" with Curl_resolv_unlink() after * use, or we will leak memory! */ struct Curl_dns_entry * Curl_fetch_addr(struct Curl_easy *data, const char *hostname, int port); /* * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache. * @param permanent iff TRUE, entry will never become stale * Returns the Curl_dns_entry entry pointer or NULL if the storage failed. */ struct Curl_dns_entry * Curl_cache_addr(struct Curl_easy *data, struct Curl_addrinfo *addr, const char *hostname, size_t hostlen, int port, bool permanent); #ifndef INADDR_NONE #define CURL_INADDR_NONE (in_addr_t) ~0 #else #define CURL_INADDR_NONE INADDR_NONE #endif /* * Function provided by the resolver backend to set DNS servers to use. */ CURLcode Curl_set_dns_servers(struct Curl_easy *data, char *servers); /* * Function provided by the resolver backend to set * outgoing interface to use for DNS requests */ CURLcode Curl_set_dns_interface(struct Curl_easy *data, const char *interf); /* * Function provided by the resolver backend to set * local IPv4 address to use as source address for DNS requests */ CURLcode Curl_set_dns_local_ip4(struct Curl_easy *data, const char *local_ip4); /* * Function provided by the resolver backend to set * local IPv6 address to use as source address for DNS requests */ CURLcode Curl_set_dns_local_ip6(struct Curl_easy *data, const char *local_ip6); /* * Clean off entries from the cache */ void Curl_hostcache_clean(struct Curl_easy *data, struct Curl_hash *hash); /* * Populate the cache with specified entries from CURLOPT_RESOLVE. */ CURLcode Curl_loadhostpairs(struct Curl_easy *data); CURLcode Curl_resolv_check(struct Curl_easy *data, struct Curl_dns_entry **dns); int Curl_resolv_getsock(struct Curl_easy *data, curl_socket_t *socks); CURLcode Curl_resolver_error(struct Curl_easy *data); #endif /* HEADER_CURL_HOSTIP_H */