* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2010, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2015, 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
*
***************************************************************************/
-#include "setup.h"
+#include "curl_setup.h"
-#include <string.h>
-
-#ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
-#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h> /* required for free() prototypes */
-#endif
-#ifdef HAVE_UNISTD_H
-#include <unistd.h> /* for the close() proto */
-#endif
#ifdef __VMS
#include <in.h>
#include <inet.h>
-#include <stdlib.h>
#endif
#ifdef HAVE_SETJMP_H
* hostip.c - method-independent resolver functions and utility functions
* hostasyn.c - functions for asynchronous name resolves
* hostsyn.c - functions for synchronous name resolves
- * hostares.c - functions for ares-using name resolves
- * hostthre.c - functions for threaded name resolves
- * hostip4.c - ipv4-specific functions
- * hostip6.c - ipv6-specific functions
+ * hostip4.c - IPv4 specific functions
+ * hostip6.c - IPv6 specific functions
*
+ * The two asynchronous name resolver backends are implemented in:
+ * asyn-ares.c - functions for ares-using name resolves
+ * asyn-thread.c - functions for threaded name resolves
+
* The hostip.h is the united header file for all this. It defines the
- * CURLRES_* defines based on the config*.h and setup.h defines.
+ * CURLRES_* defines based on the config*.h and curl_setup.h defines.
*/
/* These two symbols are for the global DNS cache */
void Curl_global_host_cache_dtor(void)
{
if(host_cache_initialized) {
+ /* first make sure that any custom "CURLOPT_RESOLVE" names are
+ cleared off */
+ Curl_hostcache_clean(NULL, &hostname_cache);
+ /* then free the remaining hash completely */
Curl_hash_clean(&hostname_cache);
host_cache_initialized = 0;
}
}
/*
- * Return a hostcache id string for the providing host + port, to be used by
+ * Return a hostcache id string for the provided host + port, to be used by
* the DNS caching.
*/
static char *
-create_hostcache_id(const char *server, int port)
+create_hostcache_id(const char *name, int port)
{
/* create and return the new allocated entry */
- return aprintf("%s:%d", server, port);
+ char *id = aprintf("%s:%d", name, port);
+ char *ptr = id;
+ if(ptr) {
+ /* lower case the name part */
+ while(*ptr && (*ptr != ':')) {
+ *ptr = (char)TOLOWER(*ptr);
+ ptr++;
+ }
+ }
+ return id;
}
struct hostcache_prune_data {
(struct hostcache_prune_data *) datap;
struct Curl_dns_entry *c = (struct Curl_dns_entry *) hc;
- return (data->now - c->timestamp >= data->cache_timeout);
+ return !c->inuse && (data->now - c->timestamp >= data->cache_timeout);
}
/*
{
struct hostcache_prune_data user;
- if( !dns || (data->set.dns_cache_timeout == -1) || !data->dns.hostcache)
- /* cache forever means never prune, and NULL hostcache means
- we can't do it */
+ if(!dns || (data->set.dns_cache_timeout == -1) || !data->dns.hostcache ||
+ dns->inuse)
+ /* cache forever means never prune, and NULL hostcache means we can't do
+ it, if it still is in use then we leave it */
return 0;
time(&user.now);
user.cache_timeout = data->set.dns_cache_timeout;
- if( !hostcache_timestamp_remove(&user,dns) )
+ if(!hostcache_timestamp_remove(&user,dns) )
return 0;
Curl_hash_clean_with_criterium(data->dns.hostcache,
sigjmp_buf curl_jmpenv;
#endif
+/*
+ * Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache.
+ *
+ * Curl_resolv() checks initially and multi_runsingle() checks each time
+ * it discovers the handle in the state WAITRESOLVE whether the hostname
+ * has already been resolved and the address has already been stored in
+ * the DNS cache. This short circuits waiting for a lot of pending
+ * lookups for the same hostname requested by different handles.
+ *
+ * Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
+ */
+struct Curl_dns_entry *
+Curl_fetch_addr(struct connectdata *conn,
+ const char *hostname,
+ int port)
+{
+ char *entry_id = NULL;
+ struct Curl_dns_entry *dns = NULL;
+ size_t entry_len;
+ struct SessionHandle *data = conn->data;
+ int stale;
+
+ /* Create an entry id, based upon the hostname and port */
+ entry_id = create_hostcache_id(hostname, port);
+ /* If we can't create the entry id, fail */
+ if(!entry_id)
+ return dns;
+
+ entry_len = strlen(entry_id);
+
+ /* See if its already in our dns cache */
+ dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
+
+ /* free the allocated entry_id again */
+ free(entry_id);
+
+ /* See whether the returned entry is stale. Done before we release lock */
+ stale = remove_entry_if_stale(data, dns);
+ if(stale) {
+ infof(data, "Hostname in DNS cache was stale, zapped\n");
+ dns = NULL; /* the memory deallocation is being handled by the hash */
+ }
+
+ return dns;
+}
/*
* Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache.
int port,
struct Curl_dns_entry **entry)
{
- char *entry_id = NULL;
struct Curl_dns_entry *dns = NULL;
- size_t entry_len;
struct SessionHandle *data = conn->data;
CURLcode result;
int rc = CURLRESOLV_ERROR; /* default to failure */
*entry = NULL;
- /* Create an entry id, based upon the hostname and port */
- entry_id = create_hostcache_id(hostname, port);
- /* If we can't create the entry id, fail */
- if(!entry_id)
- return rc;
-
- entry_len = strlen(entry_id);
-
if(data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
- /* See if its already in our dns cache */
- dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
-
- /* free the allocated entry_id again */
- free(entry_id);
-
- /* See whether the returned entry is stale. Done before we release lock */
- if( remove_entry_if_stale(data, dns) )
- dns = NULL; /* the memory deallocation is being handled by the hash */
+ dns = Curl_fetch_addr(conn, hostname, port);
if(dns) {
+ infof(data, "Hostname %s was found in DNS cache\n", hostname);
dns->inuse++; /* we use it! */
rc = CURLRESOLV_RESOLVED;
}
/* the response to our resolve call will come asynchronously at
a later time, good or bad */
/* First, check that we haven't received the info by now */
- result = Curl_is_resolved(conn, &dns);
+ result = Curl_resolver_is_resolved(conn, &dns);
if(result) /* error detected */
return CURLRESOLV_ERROR;
if(dns)
*entry = NULL;
+ if(timeoutms < 0)
+ /* got an already expired timeout */
+ return CURLRESOLV_TIMEDOUT;
+
#ifdef USE_ALARM_TIMEOUT
- if (data->set.no_signal)
+ if(data->set.no_signal)
/* Ignore the timeout when signals are disabled */
timeout = 0;
else
* Curl_resolv_unlock() unlocks the given cached DNS entry. When this has been
* made, the struct may be destroyed due to pruning. It is important that only
* one unlock is made for each Curl_resolv() call.
+ *
+ * May be called with 'data' == NULL for global cache.
*/
void Curl_resolv_unlock(struct SessionHandle *data, struct Curl_dns_entry *dns)
{
DEBUGASSERT(dns && (dns->inuse>0));
- if(data->share)
+ if(data && data->share)
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
dns->inuse--;
/* only free if nobody is using AND it is not in hostcache (timestamp ==
0) */
- if (dns->inuse == 0 && dns->timestamp == 0) {
+ if(dns->inuse == 0 && dns->timestamp == 0) {
Curl_freeaddrinfo(dns->addr);
free(dns);
}
- if(data->share)
+ if(data && data->share)
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
}
/* mark the entry as not in hostcache */
p->timestamp = 0;
- if (p->inuse == 0) {
+ if(p->inuse == 0) {
Curl_freeaddrinfo(p->addr);
free(p);
}
return Curl_hash_alloc(7, Curl_hash_str, Curl_str_key_compare, freednsentry);
}
+static int hostcache_inuse(void *data, void *hc)
+{
+ struct Curl_dns_entry *c = (struct Curl_dns_entry *) hc;
+
+ if(c->inuse == 1)
+ Curl_resolv_unlock(data, c);
+
+ return 1; /* free all entries */
+}
+
+/*
+ * Curl_hostcache_clean()
+ *
+ * This _can_ be called with 'data' == NULL but then of course no locking
+ * can be done!
+ */
+void Curl_hostcache_clean(struct SessionHandle *data,
+ struct curl_hash *hash)
+{
+ /* Entries added to the hostcache with the CURLOPT_RESOLVE function are
+ * still present in the cache with the inuse counter set to 1. Detect them
+ * and cleanup!
+ */
+ Curl_hash_clean_with_criterium(hash, data, hostcache_inuse);
+}
+
+
+CURLcode Curl_loadhostpairs(struct SessionHandle *data)
+{
+ struct curl_slist *hostp;
+ char hostname[256];
+ char address[256];
+ int port;
+
+ for(hostp = data->change.resolve; hostp; hostp = hostp->next ) {
+ if(!hostp->data)
+ continue;
+ if(hostp->data[0] == '-') {
+ /* TODO: mark an entry for removal */
+ }
+ else if(3 == sscanf(hostp->data, "%255[^:]:%d:%255s", hostname, &port,
+ address)) {
+ struct Curl_dns_entry *dns;
+ Curl_addrinfo *addr;
+ char *entry_id;
+ size_t entry_len;
+
+ addr = Curl_str2addr(address, port);
+ if(!addr) {
+ infof(data, "Resolve %s found illegal!\n", hostp->data);
+ continue;
+ }
+
+ /* Create an entry id, based upon the hostname and port */
+ entry_id = create_hostcache_id(hostname, port);
+ /* If we can't create the entry id, fail */
+ if(!entry_id) {
+ Curl_freeaddrinfo(addr);
+ return CURLE_OUT_OF_MEMORY;
+ }
+
+ entry_len = strlen(entry_id);
+
+ if(data->share)
+ Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
+
+ /* See if its already in our dns cache */
+ dns = Curl_hash_pick(data->dns.hostcache, entry_id, entry_len+1);
+
+ /* free the allocated entry_id again */
+ free(entry_id);
+
+ if(!dns)
+ /* if not in the cache already, put this host in the cache */
+ dns = Curl_cache_addr(data, addr, hostname, port);
+ else
+ /* this is a duplicate, free it again */
+ Curl_freeaddrinfo(addr);
+
+ if(data->share)
+ Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
+
+ if(!dns) {
+ Curl_freeaddrinfo(addr);
+ return CURLE_OUT_OF_MEMORY;
+ }
+ infof(data, "Added %s:%d:%s to DNS cache\n",
+ hostname, port, address);
+ }
+ }
+ data->change.resolve = NULL; /* dealt with now */
+
+ return CURLE_OK;
+}