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#ifndef HEADER_CURL_HOSTIP_H
#define HEADER_CURL_HOSTIP_H
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, 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 "curlx/timeval.h" /* for timediff_t */
#include "asyn.h"
#include "httpsrr.h"
#include <setjmp.h>
#ifdef USE_HTTPSRR
# include <stdint.h>
#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 */
struct addrinfo;
struct hostent;
struct Curl_easy;
struct connectdata;
struct easy_pollset;
enum alpnid {
ALPN_none = 0,
ALPN_h1 = CURLALTSVC_H1,
ALPN_h2 = CURLALTSVC_H2,
ALPN_h3 = CURLALTSVC_H3
};
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) */
struct curltime 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];
};
struct Curl_dnscache {
struct Curl_hash entries;
};
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!
*/
CURLcode Curl_resolv(struct Curl_easy *data,
const char *hostname,
int port,
int ip_version,
bool allowDOH,
struct Curl_dns_entry **dnsentry);
CURLcode Curl_resolv_blocking(struct Curl_easy *data,
const char *hostname,
int port,
int ip_version,
struct Curl_dns_entry **dnsentry);
CURLcode Curl_resolv_timeout(struct Curl_easy *data,
const char *hostname, int port,
int ip_version,
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
/* 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_dnscache_init(struct Curl_dnscache *dns, size_t hashsize);
void Curl_dnscache_destroy(struct Curl_dnscache *dns);
/* prune old entries from the DNS cache */
void Curl_dnscache_prune(struct Curl_easy *data);
/* clear the DNS cache */
void Curl_dnscache_clear(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,
struct Curl_dns_entry *dns,
bool *protocol_connect);
/*
* 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);
/*
* Make a `Curl_dns_entry`.
* Creates a dnscache entry *without* adding it to a dnscache. This allows
* further modifications of the entry *before* then adding it to a cache.
*
* The entry is created with a reference count of 1.
* Use `Curl_resolv_unlink()` to release your hold on it.
*
* The call takes ownership of `addr`and makes a copy of `hostname`.
*
* Returns entry or NULL on OOM.
*/
struct Curl_dns_entry *
Curl_dnscache_mk_entry(struct Curl_easy *data,
struct Curl_addrinfo *addr,
const char *hostname,
size_t hostlen, /* length or zero */
int port,
bool permanent);
/*
* Curl_dnscache_get() 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_dnscache_get(struct Curl_easy *data,
const char *hostname,
int port, int ip_version);
/*
* Curl_dnscache_addr() adds `entry` to the cache, increasing its
* reference count on success.
*/
CURLcode Curl_dnscache_add(struct Curl_easy *data,
struct Curl_dns_entry *entry);
/*
* Populate the cache with specified entries from CURLOPT_RESOLVE.
*/
CURLcode Curl_loadhostpairs(struct Curl_easy *data);
#ifdef USE_CURL_ASYNC
CURLcode Curl_resolv_check(struct Curl_easy *data,
struct Curl_dns_entry **dns);
#else
#define Curl_resolv_check(x,y) CURLE_NOT_BUILT_IN
#endif
CURLcode Curl_resolv_pollset(struct Curl_easy *data,
struct easy_pollset *ps);
CURLcode Curl_resolver_error(struct Curl_easy *data, const char *detail);
#ifdef CURLRES_SYNCH
/*
* Curl_sync_getaddrinfo() is the non-async low-level name resolve API.
* There are several versions of this function - depending on IPV6
* support and platform.
*/
struct Curl_addrinfo *Curl_sync_getaddrinfo(struct Curl_easy *data,
const char *hostname,
int port,
int ip_version);
#endif
#endif /* HEADER_CURL_HOSTIP_H */