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			C++
		
	
	
	
	
	
			
		
		
	
	
			992 lines
		
	
	
	
		
			31 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /* Copyright (c) 2000, 2013, Oracle and/or its affiliates.
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|    Copyright (c) 2011, 2014, SkySQL Ab.
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| 
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|    This program is free software; you can redistribute it and/or modify
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|    it under the terms of the GNU General Public License as published by
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|    the Free Software Foundation; version 2 of the License.
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| 
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|    This program is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|    GNU General Public License for more details.
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| 
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|    You should have received a copy of the GNU General Public License
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|    along with this program; if not, write to the Free Software
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|    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1335  USA */
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| 
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| 
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| /**
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|   @file
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| 
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|   @brief
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|   Get hostname for an IP address.
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| 
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|   Hostnames are checked with reverse name lookup and checked that they
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|   doesn't resemble an IP address.
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| */
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| #include "mariadb.h"
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| #include "sql_priv.h"
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| #include "unireg.h"                             // SPECIAL_NO_HOST_CACHE
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| #include "hostname.h"
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| #ifndef _WIN32
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| #include <netdb.h>        // getservbyname, servent
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| #endif
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| #include "hash_filo.h"
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| #include <m_ctype.h>
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| #include "log.h"                                // sql_print_warning,
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|                                                 // sql_print_information
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| #include "violite.h"                            // vio_getnameinfo,
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|                                                 // vio_get_normalized_ip_string
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| #ifdef	__cplusplus
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| extern "C" {					// Because of SCO 3.2V4.2
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| #endif
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| #if !defined( _WIN32)
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| #ifdef HAVE_SYS_UN_H
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| #include <sys/un.h>
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| #endif
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| #include <sys/utsname.h>
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| #endif // _WIN32
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| #ifdef	__cplusplus
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| }
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| #endif
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| 
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| Host_errors::Host_errors()
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| : m_connect(0),
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|   m_host_blocked(0),
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|   m_nameinfo_transient(0),
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|   m_nameinfo_permanent(0),
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|   m_format(0),
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|   m_addrinfo_transient(0),
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|   m_addrinfo_permanent(0),
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|   m_FCrDNS(0),
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|   m_host_acl(0),
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|   m_no_auth_plugin(0),
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|   m_auth_plugin(0),
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|   m_handshake(0),
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|   m_proxy_user(0),
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|   m_proxy_user_acl(0),
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|   m_authentication(0),
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|   m_ssl(0),
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|   m_max_user_connection(0),
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|   m_max_user_connection_per_hour(0),
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|   m_default_database(0),
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|   m_init_connect(0),
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|   m_local(0)
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| {}
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| 
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| Host_errors::~Host_errors() = default;
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| 
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| void Host_errors::reset()
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| {
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|   m_connect= 0;
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|   m_host_blocked= 0;
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|   m_nameinfo_transient= 0;
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|   m_nameinfo_permanent= 0;
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|   m_format= 0;
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|   m_addrinfo_transient= 0;
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|   m_addrinfo_permanent= 0;
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|   m_FCrDNS= 0;
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|   m_host_acl= 0;
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|   m_no_auth_plugin= 0;
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|   m_auth_plugin= 0;
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|   m_handshake= 0;
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|   m_proxy_user= 0;
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|   m_proxy_user_acl= 0;
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|   m_authentication= 0;
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|   m_ssl= 0;
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|   m_max_user_connection= 0;
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|   m_max_user_connection_per_hour= 0;
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|   m_default_database= 0;
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|   m_init_connect= 0;
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|   m_local= 0;
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| }
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| 
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| void Host_errors::aggregate(const Host_errors *errors)
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| {
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|   m_connect+= errors->m_connect;
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|   m_host_blocked+= errors->m_host_blocked;
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|   m_nameinfo_transient+= errors->m_nameinfo_transient;
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|   m_nameinfo_permanent+= errors->m_nameinfo_permanent;
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|   m_format+= errors->m_format;
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|   m_addrinfo_transient+= errors->m_addrinfo_transient;
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|   m_addrinfo_permanent+= errors->m_addrinfo_permanent;
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|   m_FCrDNS+= errors->m_FCrDNS;
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|   m_host_acl+= errors->m_host_acl;
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|   m_no_auth_plugin+= errors->m_no_auth_plugin;
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|   m_auth_plugin+= errors->m_auth_plugin;
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|   m_handshake+= errors->m_handshake;
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|   m_proxy_user+= errors->m_proxy_user;
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|   m_proxy_user_acl+= errors->m_proxy_user_acl;
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|   m_authentication+= errors->m_authentication;
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|   m_ssl+= errors->m_ssl;
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|   m_max_user_connection+= errors->m_max_user_connection;
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|   m_max_user_connection_per_hour+= errors->m_max_user_connection_per_hour;
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|   m_default_database+= errors->m_default_database;
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|   m_init_connect+= errors->m_init_connect;
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|   m_local+= errors->m_local;
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| }
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| 
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| static Hash_filo<Host_entry> *hostname_cache;
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| ulong host_cache_size;
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| 
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| void hostname_cache_refresh()
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| {
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|   hostname_cache->clear();
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| }
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| 
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| uint hostname_cache_size()
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| {
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|   return hostname_cache->size();
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| }
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| 
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| void hostname_cache_resize(uint size)
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| {
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|   hostname_cache->resize(size);
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| }
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| 
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| bool hostname_cache_init()
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| {
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|   Host_entry tmp;
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|   uint key_offset= (uint) ((char*) (&tmp.ip_key) - (char*) &tmp);
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| 
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|   if (!(hostname_cache= new Hash_filo<Host_entry>(key_memory_host_cache_hostname,
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|                              host_cache_size, key_offset, HOST_ENTRY_KEY_SIZE,
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|                              NULL, my_free, &my_charset_bin)))
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|     return 1;
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| 
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|   hostname_cache->clear();
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| 
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|   return 0;
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| }
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| 
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| void hostname_cache_free()
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| {
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|   delete hostname_cache;
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|   hostname_cache= NULL;
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| }
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| 
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| void hostname_cache_lock()
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| {
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|   mysql_mutex_lock(&hostname_cache->lock);
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| }
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| 
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| void hostname_cache_unlock()
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| {
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|   mysql_mutex_unlock(&hostname_cache->lock);
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| }
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| 
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| static void prepare_hostname_cache_key(const char *ip_string,
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|                                        char *ip_key)
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| {
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|   size_t ip_string_length= strlen(ip_string);
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|   DBUG_ASSERT(ip_string_length < HOST_ENTRY_KEY_SIZE);
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| 
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|   memset(ip_key, 0, HOST_ENTRY_KEY_SIZE);
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|   memcpy(ip_key, ip_string, ip_string_length);
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| }
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| 
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| Host_entry *hostname_cache_first()
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| { return hostname_cache->first(); }
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| 
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| static inline Host_entry *hostname_cache_search(const char *ip_key)
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| {
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|   return hostname_cache->search((uchar *) ip_key, HOST_ENTRY_KEY_SIZE);
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| }
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| 
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| static void add_hostname_impl(const char *ip_key, const char *hostname,
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|                               bool validated, Host_errors *errors,
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|                               ulonglong now)
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| {
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|   Host_entry *entry;
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|   bool need_add= false;
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| 
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|   entry= hostname_cache_search(ip_key);
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| 
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|   if (likely(entry == NULL))
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|   {
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|     entry= (Host_entry *) my_malloc(key_memory_host_cache_hostname,
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|                                     sizeof (Host_entry), 0);
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|     if (entry == NULL)
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|       return;
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| 
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|     need_add= true;
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|     memcpy(&entry->ip_key, ip_key, HOST_ENTRY_KEY_SIZE);
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|     entry->m_errors.reset();
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|     entry->m_hostname_length= 0;
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|     entry->m_host_validated= false;
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|     entry->m_first_seen= now;
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|     entry->m_last_seen= now;
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|     entry->m_first_error_seen= 0;
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|     entry->m_last_error_seen= 0;
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|   }
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|   else
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|   {
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|     entry->m_last_seen= now;
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|   }
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| 
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|   if (validated)
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|   {
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|     if (hostname != NULL)
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|     {
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|       size_t len= strlen(hostname);
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|       if (len > sizeof(entry->m_hostname) - 1)
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|         len= sizeof(entry->m_hostname) - 1;
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|       memcpy(entry->m_hostname, hostname, len);
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|       entry->m_hostname[len]= '\0';
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|       entry->m_hostname_length= (uint)len;
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| 
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|       DBUG_PRINT("info",
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|                  ("Adding/Updating '%s' -> '%s' (validated) to the hostname cache...'",
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|                  (const char *) ip_key,
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|                  (const char *) entry->m_hostname));
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|     }
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|     else
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|     {
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|       entry->m_hostname_length= 0;
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|       DBUG_PRINT("info",
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|                  ("Adding/Updating '%s' -> NULL (validated) to the hostname cache...'",
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|                  (const char *) ip_key));
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|     }
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|     entry->m_host_validated= true;
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|     /*
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|       New errors that are considered 'blocking',
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|       that will eventually cause the IP to be black listed and blocked.
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|     */
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|     errors->sum_connect_errors();
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|   }
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|   else
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|   {
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|     entry->m_hostname_length= 0;
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|     entry->m_host_validated= false;
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|     /* Do not count new blocking errors during DNS failures. */
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|     errors->clear_connect_errors();
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|     DBUG_PRINT("info",
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|                ("Adding/Updating '%s' -> NULL (not validated) to the hostname cache...'",
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|                (const char *) ip_key));
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|   }
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| 
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|   if (errors->has_error())
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|     entry->set_error_timestamps(now);
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| 
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|   entry->m_errors.aggregate(errors);
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| 
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|   if (need_add)
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|     hostname_cache->add(entry);
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| 
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|   return;
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| }
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| 
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| static void add_hostname(const char *ip_key, const char *hostname,
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|                          bool validated, Host_errors *errors)
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| {
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|   if (specialflag & SPECIAL_NO_HOST_CACHE)
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|     return;
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| 
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|   ulonglong now= my_hrtime().val;
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| 
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|   mysql_mutex_lock(&hostname_cache->lock);
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| 
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|   add_hostname_impl(ip_key, hostname, validated, errors, now);
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| 
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|   mysql_mutex_unlock(&hostname_cache->lock);
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| 
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|   return;
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| }
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| 
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| void inc_host_errors(const char *ip_string, Host_errors *errors)
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| {
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|   if (!ip_string)
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|     return;
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| 
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|   ulonglong now= my_hrtime().val;
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|   char ip_key[HOST_ENTRY_KEY_SIZE];
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|   prepare_hostname_cache_key(ip_string, ip_key);
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| 
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|   mysql_mutex_lock(&hostname_cache->lock);
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| 
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|   Host_entry *entry= hostname_cache_search(ip_key);
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| 
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|   if (entry)
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|   {
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|     if (entry->m_host_validated)
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|       errors->sum_connect_errors();
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|     else
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|       errors->clear_connect_errors();
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| 
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|     entry->m_errors.aggregate(errors);
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|     entry->set_error_timestamps(now);
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|   }
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| 
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|   mysql_mutex_unlock(&hostname_cache->lock);
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| }
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| 
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| void reset_host_connect_errors(const char *ip_string)
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| {
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|   if (!ip_string)
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|     return;
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| 
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|   char ip_key[HOST_ENTRY_KEY_SIZE];
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|   prepare_hostname_cache_key(ip_string, ip_key);
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| 
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|   mysql_mutex_lock(&hostname_cache->lock);
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| 
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|   Host_entry *entry= hostname_cache_search(ip_key);
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| 
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|   if (entry)
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|     entry->m_errors.clear_connect_errors();
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| 
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|   mysql_mutex_unlock(&hostname_cache->lock);
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| }
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| 
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| static inline bool is_ip_loopback(const struct sockaddr *ip)
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| {
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|   switch (ip->sa_family) {
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|   case AF_INET:
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|     {
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|       /* Check for IPv4 127.0.0.1. */
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|       struct in_addr *ip4= &((struct sockaddr_in *) ip)->sin_addr;
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|       return ntohl(ip4->s_addr) == INADDR_LOOPBACK;
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|     }
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| 
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| #ifdef HAVE_IPV6
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|   case AF_INET6:
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|     {
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|       /* Check for IPv6 ::1. */
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|       struct in6_addr *ip6= &((struct sockaddr_in6 *) ip)->sin6_addr;
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|       return IN6_IS_ADDR_LOOPBACK(ip6);
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|     }
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| #endif /* HAVE_IPV6 */
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| 
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|   default:
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|     return FALSE;
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|   }
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| }
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| 
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| static inline bool is_hostname_valid(const char *hostname)
 | |
| {
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|   /*
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|     A hostname is invalid if it starts with a number followed by a dot
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|     (IPv4 address).
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|   */
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| 
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|   if (!my_isdigit(&my_charset_latin1, hostname[0]))
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|     return TRUE;
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| 
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|   const char *p= hostname + 1;
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| 
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|   while (my_isdigit(&my_charset_latin1, *p))
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|     ++p;
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| 
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|   return *p != '.';
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| }
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| 
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| /**
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|   Resolve IP-address to host name.
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| 
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|   This function does the following things:
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|     - resolves IP-address;
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|     - employs Forward Confirmed Reverse DNS technique to validate IP-address;
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|     - returns host name if IP-address is validated;
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|     - set value to out-variable connect_errors -- this variable represents the
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|       number of connection errors from the specified IP-address.
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|     - update the host_cache statistics
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| 
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|   NOTE: connect_errors are counted (are supported) only for the clients
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|   where IP-address can be resolved and FCrDNS check is passed.
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| 
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|   @param [in]  ip_storage IP address (sockaddr). Must be set.
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|   @param [in]  ip_string  IP address (string). Must be set.
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|   @param [out] hostname
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|   @param [out] connect_errors
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| 
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|   @return Error status
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|   @retval 0 Success
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|   @retval RC_BLOCKED_HOST The host is blocked.
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| 
 | |
|   The function does not set/report MySQL server error in case of failure.
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|   It's caller's responsibility to handle failures of this function
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|   properly.
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| */
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| 
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| int ip_to_hostname(struct sockaddr_storage *ip_storage,
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|                    const char *ip_string,
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|                    const char **hostname,
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|                    uint *connect_errors)
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| {
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|   const struct sockaddr *ip= (const sockaddr *) ip_storage;
 | |
|   int err_code;
 | |
|   bool err_status __attribute__((unused));
 | |
|   Host_errors errors;
 | |
| 
 | |
|   DBUG_ENTER("ip_to_hostname");
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|   DBUG_PRINT("info", ("IP address: '%s'; family: %d.",
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|                       (const char *) ip_string,
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|                       (int) ip->sa_family));
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| 
 | |
|   /* Default output values, for most cases. */
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|   *hostname= NULL;
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|   *connect_errors= 0;
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| 
 | |
|   /* Check if we have loopback address (127.0.0.1 or ::1). */
 | |
| 
 | |
|   if (is_ip_loopback(ip))
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|   {
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|     DBUG_PRINT("info", ("Loopback address detected."));
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| 
 | |
|     /* Do not count connect errors from localhost. */
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|     *hostname= my_localhost;
 | |
| 
 | |
|     DBUG_RETURN(0);
 | |
|   }
 | |
| 
 | |
|   /* Prepare host name cache key. */
 | |
| 
 | |
|   char ip_key[HOST_ENTRY_KEY_SIZE];
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|   prepare_hostname_cache_key(ip_string, ip_key);
 | |
| 
 | |
|   /* Check first if we have host name in the cache. */
 | |
| 
 | |
|   if (!(specialflag & SPECIAL_NO_HOST_CACHE))
 | |
|   {
 | |
|     ulonglong now= my_hrtime().val;
 | |
| 
 | |
|     mysql_mutex_lock(&hostname_cache->lock);
 | |
| 
 | |
|     Host_entry *entry= hostname_cache_search(ip_key);
 | |
| 
 | |
|     if (entry)
 | |
|     {
 | |
|       entry->m_last_seen= now;
 | |
|       *connect_errors= entry->m_errors.m_connect;
 | |
| 
 | |
|       if (unlikely(entry->m_errors.m_connect >= max_connect_errors))
 | |
|       {
 | |
|         entry->m_errors.m_host_blocked++;
 | |
|         entry->set_error_timestamps(now);
 | |
|         mysql_mutex_unlock(&hostname_cache->lock);
 | |
|         DBUG_RETURN(RC_BLOCKED_HOST);
 | |
|       }
 | |
| 
 | |
|       /*
 | |
|         If there is an IP -> HOSTNAME association in the cache,
 | |
|         but for a hostname that was not validated,
 | |
|         do not return that hostname: perform the network validation again.
 | |
|       */
 | |
|       if (entry->m_host_validated)
 | |
|       {
 | |
|         if (entry->m_hostname_length)
 | |
|           *hostname= my_strdup(key_memory_host_cache_hostname,
 | |
|                                entry->m_hostname, MYF(0));
 | |
| 
 | |
|         DBUG_PRINT("info",("IP (%s) has been found in the cache. "
 | |
|                            "Hostname: '%s'",
 | |
|                            (const char *) ip_key,
 | |
|                            (const char *) (*hostname? *hostname : "null")
 | |
|                           ));
 | |
| 
 | |
|         mysql_mutex_unlock(&hostname_cache->lock);
 | |
| 
 | |
|         DBUG_RETURN(0);
 | |
|       }
 | |
|     }
 | |
| 
 | |
|     mysql_mutex_unlock(&hostname_cache->lock);
 | |
|   }
 | |
| 
 | |
|   /*
 | |
|     Resolve host name. Return an error if a host name can not be resolved
 | |
|     (instead of returning the numeric form of the host name).
 | |
|   */
 | |
| 
 | |
|   char hostname_buffer[NI_MAXHOST];
 | |
| 
 | |
|   DBUG_PRINT("info", ("Resolving '%s'...", (const char *) ip_key));
 | |
| 
 | |
|   err_code= vio_getnameinfo(ip, hostname_buffer, NI_MAXHOST, NULL, 0,
 | |
|                             NI_NAMEREQD);
 | |
| 
 | |
|   /*
 | |
|   ===========================================================================
 | |
|   DEBUG code only (begin)
 | |
|   Simulate various output from vio_getnameinfo().
 | |
|   ===========================================================================
 | |
|   */
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_error_noname",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "<garbage>");
 | |
|                     err_code= EAI_NONAME;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_error_again",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "<garbage>");
 | |
|                     err_code= EAI_AGAIN;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_fake_ipv4",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "santa.claus.ipv4.example.com");
 | |
|                     err_code= 0;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_fake_ipv6",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "santa.claus.ipv6.example.com");
 | |
|                     err_code= 0;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_format_ipv4",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "12.12.12.12");
 | |
|                     err_code= 0;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_format_ipv6",
 | |
|                   {
 | |
|                     safe_strcpy(hostname_buffer, sizeof(hostname_buffer),
 | |
|                                 "12:DEAD:BEEF:0");
 | |
|                     err_code= 0;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getnameinfo_fake_long_host",
 | |
|                   {
 | |
|                     strcpy(hostname_buffer, "host5678901_345678902_345678903_345678904_345678905_345678906_345678907_345678908_345678909_345678910_345678911_345678912_345678913_345678914_345678915_345678916_345678917_345678918_345678919_345678920_345678921_345678922_345678923_345678924_345678925_345");
 | |
|                     err_code= 0;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   /*
 | |
|   ===========================================================================
 | |
|   DEBUG code only (end)
 | |
|   ===========================================================================
 | |
|   */
 | |
| 
 | |
|   if (err_code)
 | |
|   {
 | |
|     // NOTE: gai_strerror() returns a string ending by a dot.
 | |
| 
 | |
|     DBUG_PRINT("error", ("IP address '%s' could not be resolved: %s",
 | |
|                          (const char *) ip_key,
 | |
|                          (const char *) gai_strerror(err_code)));
 | |
| 
 | |
|     sql_print_warning("IP address '%s' could not be resolved: %s",
 | |
|                       (const char *) ip_key,
 | |
|                       (const char *) gai_strerror(err_code));
 | |
| 
 | |
|     bool validated;
 | |
|     if (vio_is_no_name_error(err_code))
 | |
|     {
 | |
|       /*
 | |
|         The no-name error means that there is no reverse address mapping
 | |
|         for the IP address. A host name can not be resolved.
 | |
|       */
 | |
|       errors.m_nameinfo_permanent= 1;
 | |
|       validated= true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|       /*
 | |
|         If it is not the no-name error, we should not cache the hostname
 | |
|         (or rather its absence), because the failure might be transient.
 | |
|         Only the ip error statistics are cached.
 | |
|       */
 | |
|       errors.m_nameinfo_transient= 1;
 | |
|       validated= false;
 | |
|     }
 | |
|     add_hostname(ip_key, NULL, validated, &errors);
 | |
| 
 | |
|     DBUG_RETURN(0);
 | |
|   }
 | |
| 
 | |
|   DBUG_PRINT("info", ("IP '%s' resolved to '%s'.",
 | |
|                       (const char *) ip_key,
 | |
|                       (const char *) hostname_buffer));
 | |
| 
 | |
|   /*
 | |
|     Validate hostname: the server does not accept host names, which
 | |
|     resemble IP addresses.
 | |
| 
 | |
|     The thing is that theoretically, a host name can be in a form of IPv4
 | |
|     address (123.example.org, or 1.2 or even 1.2.3.4). We have to deny such
 | |
|     host names because ACL-systems is not designed to work with them.
 | |
| 
 | |
|     For example, it is possible to specify a host name mask (like
 | |
|     192.168.1.%) for an ACL rule. Then, if IPv4-like hostnames are allowed,
 | |
|     there is a security hole: instead of allowing access for
 | |
|     192.168.1.0/255 network (which was assumed by the user), the access
 | |
|     will be allowed for host names like 192.168.1.example.org.
 | |
|   */
 | |
| 
 | |
|   if (!is_hostname_valid(hostname_buffer))
 | |
|   {
 | |
|     DBUG_PRINT("error", ("IP address '%s' has been resolved "
 | |
|                          "to the host name '%s', which resembles "
 | |
|                          "IPv4-address itself.",
 | |
|                          (const char *) ip_key,
 | |
|                          (const char *) hostname_buffer));
 | |
| 
 | |
|     sql_print_warning("IP address '%s' has been resolved "
 | |
|                       "to the host name '%s', which resembles "
 | |
|                       "IPv4-address itself.",
 | |
|                       (const char *) ip_key,
 | |
|                       (const char *) hostname_buffer);
 | |
| 
 | |
|     errors.m_format= 1;
 | |
|     add_hostname(ip_key, hostname_buffer, false, &errors);
 | |
| 
 | |
|     DBUG_RETURN(false);
 | |
|   }
 | |
| 
 | |
|   /* Get IP-addresses for the resolved host name (FCrDNS technique). */
 | |
| 
 | |
|   struct addrinfo hints;
 | |
|   struct addrinfo *addr_info_list;
 | |
|   /*
 | |
|     Makes fault injection with DBUG_EXECUTE_IF easier.
 | |
|     Invoking free_addr_info(NULL) crashes on some platforms.
 | |
|   */
 | |
|   bool free_addr_info_list= false;
 | |
| 
 | |
|   memset(&hints, 0, sizeof (struct addrinfo));
 | |
|   hints.ai_flags= AI_PASSIVE;
 | |
|   hints.ai_socktype= SOCK_STREAM;
 | |
|   hints.ai_family= AF_UNSPEC;
 | |
| 
 | |
|   DBUG_PRINT("info", ("Getting IP addresses for hostname '%s'...",
 | |
|                       (const char *) hostname_buffer));
 | |
| 
 | |
|   err_code= getaddrinfo(hostname_buffer, NULL, &hints, &addr_info_list);
 | |
|   if (err_code == 0)
 | |
|     free_addr_info_list= true;
 | |
| 
 | |
|   /*
 | |
|   ===========================================================================
 | |
|   DEBUG code only (begin)
 | |
|   Simulate various output from getaddrinfo().
 | |
|   ===========================================================================
 | |
|   */
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_error_noname",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     addr_info_list= NULL;
 | |
|                     err_code= EAI_NONAME;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_error_again",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     addr_info_list= NULL;
 | |
|                     err_code= EAI_AGAIN;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_fake_bad_ipv4",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     struct sockaddr_in *debug_addr;
 | |
|                     /*
 | |
|                       Not thread safe, which is ok.
 | |
|                       Only one connection at a time is tested with
 | |
|                       fault injection.
 | |
|                     */
 | |
|                     static struct sockaddr_in debug_sock_addr[2];
 | |
|                     static struct addrinfo debug_addr_info[2];
 | |
|                     /* Simulating ipv4 192.0.2.126 */
 | |
|                     debug_addr= & debug_sock_addr[0];
 | |
|                     debug_addr->sin_family= AF_INET;
 | |
|                     inet_pton(AF_INET,"192.0.2.126", &debug_addr->sin_addr);
 | |
| 
 | |
|                     /* Simulating ipv4 192.0.2.127 */
 | |
|                     debug_addr= & debug_sock_addr[1];
 | |
|                     debug_addr->sin_family= AF_INET;
 | |
|                     inet_pton(AF_INET,"192.0.2.127", &debug_addr->sin_addr);
 | |
| 
 | |
|                     debug_addr_info[0].ai_addr= (struct sockaddr*) & debug_sock_addr[0];
 | |
|                     debug_addr_info[0].ai_addrlen= sizeof (struct sockaddr_in);
 | |
|                     debug_addr_info[0].ai_next= & debug_addr_info[1];
 | |
| 
 | |
|                     debug_addr_info[1].ai_addr= (struct sockaddr*) & debug_sock_addr[1];
 | |
|                     debug_addr_info[1].ai_addrlen= sizeof (struct sockaddr_in);
 | |
|                     debug_addr_info[1].ai_next= NULL;
 | |
| 
 | |
|                     addr_info_list= & debug_addr_info[0];
 | |
|                     err_code= 0;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_fake_good_ipv4",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     struct sockaddr_in *debug_addr;
 | |
|                     static struct sockaddr_in debug_sock_addr[2];
 | |
|                     static struct addrinfo debug_addr_info[2];
 | |
|                     /* Simulating ipv4 192.0.2.5 */
 | |
|                     debug_addr= & debug_sock_addr[0];
 | |
|                     debug_addr->sin_family= AF_INET;
 | |
|                     inet_pton(AF_INET,"192.0.2.5", &debug_addr->sin_addr);
 | |
| 
 | |
|                     /* Simulating ipv4 192.0.2.4 */
 | |
|                     debug_addr= & debug_sock_addr[1];
 | |
|                     debug_addr->sin_family= AF_INET;
 | |
|                     inet_pton(AF_INET,"192.0.2.4", &debug_addr->sin_addr);
 | |
| 
 | |
|                     debug_addr_info[0].ai_addr= (struct sockaddr*) & debug_sock_addr[0];
 | |
|                     debug_addr_info[0].ai_addrlen= sizeof (struct sockaddr_in);
 | |
|                     debug_addr_info[0].ai_next= & debug_addr_info[1];
 | |
| 
 | |
|                     debug_addr_info[1].ai_addr= (struct sockaddr*) & debug_sock_addr[1];
 | |
|                     debug_addr_info[1].ai_addrlen= sizeof (struct sockaddr_in);
 | |
|                     debug_addr_info[1].ai_next= NULL;
 | |
| 
 | |
|                     addr_info_list= & debug_addr_info[0];
 | |
|                     err_code= 0;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
| #ifdef HAVE_IPV6
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_fake_bad_ipv6",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     struct sockaddr_in6 *debug_addr;
 | |
|                     struct in6_addr *ip6;
 | |
|                     /*
 | |
|                       Not thread safe, which is ok.
 | |
|                       Only one connection at a time is tested with
 | |
|                       fault injection.
 | |
|                     */
 | |
|                     static struct sockaddr_in6 debug_sock_addr[2];
 | |
|                     static struct addrinfo debug_addr_info[2];
 | |
|                     /* Simulating ipv6 2001:DB8::6:7E */
 | |
|                     debug_addr= & debug_sock_addr[0];
 | |
|                     debug_addr->sin6_family= AF_INET6;
 | |
|                     ip6= & debug_addr->sin6_addr;
 | |
|                     inet_pton(AF_INET6,"2001:DB8::6:7E",ip6);
 | |
| 
 | |
|                     /* Simulating ipv6 2001:DB8::6:7F */
 | |
|                     debug_addr= & debug_sock_addr[1];
 | |
|                     debug_addr->sin6_family= AF_INET6;
 | |
|                     ip6= & debug_addr->sin6_addr;
 | |
|                     inet_pton(AF_INET6,"2001:DB8::6:7F",ip6);
 | |
| 
 | |
|                     debug_addr_info[0].ai_addr= (struct sockaddr*) & debug_sock_addr[0];
 | |
|                     debug_addr_info[0].ai_addrlen= sizeof (struct sockaddr_in6);
 | |
|                     debug_addr_info[0].ai_next= & debug_addr_info[1];
 | |
| 
 | |
|                     debug_addr_info[1].ai_addr= (struct sockaddr*) & debug_sock_addr[1];
 | |
|                     debug_addr_info[1].ai_addrlen= sizeof (struct sockaddr_in6);
 | |
|                     debug_addr_info[1].ai_next= NULL;
 | |
| 
 | |
|                     addr_info_list= & debug_addr_info[0];
 | |
|                     err_code= 0;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| 
 | |
|   DBUG_EXECUTE_IF("getaddrinfo_fake_good_ipv6",
 | |
|                   {
 | |
|                     if (free_addr_info_list)
 | |
|                       freeaddrinfo(addr_info_list);
 | |
| 
 | |
|                     struct sockaddr_in6 *debug_addr;
 | |
|                     struct in6_addr *ip6;
 | |
|                     /*
 | |
|                       Not thread safe, which is ok.
 | |
|                       Only one connection at a time is tested with
 | |
|                       fault injection.
 | |
|                     */
 | |
|                     static struct sockaddr_in6 debug_sock_addr[2];
 | |
|                     static struct addrinfo debug_addr_info[2];
 | |
|                     /* Simulating ipv6 2001:DB8::6:7 */
 | |
|                     debug_addr= & debug_sock_addr[0];
 | |
|                     debug_addr->sin6_family= AF_INET6;
 | |
|                     ip6= & debug_addr->sin6_addr;
 | |
|                     ip6->s6_addr[ 0] = 0x20;
 | |
|                     ip6->s6_addr[ 1] = 0x01;
 | |
|                     ip6->s6_addr[ 2] = 0x0d;
 | |
|                     ip6->s6_addr[ 3] = 0xb8;
 | |
|                     ip6->s6_addr[ 4] = 0x00;
 | |
|                     ip6->s6_addr[ 5] = 0x00;
 | |
|                     ip6->s6_addr[ 6] = 0x00;
 | |
|                     ip6->s6_addr[ 7] = 0x00;
 | |
|                     ip6->s6_addr[ 8] = 0x00;
 | |
|                     ip6->s6_addr[ 9] = 0x00;
 | |
|                     ip6->s6_addr[10] = 0x00;
 | |
|                     ip6->s6_addr[11] = 0x00;
 | |
|                     ip6->s6_addr[12] = 0x00;
 | |
|                     ip6->s6_addr[13] = 0x06;
 | |
|                     ip6->s6_addr[14] = 0x00;
 | |
|                     ip6->s6_addr[15] = 0x07;
 | |
| 
 | |
|                     /* Simulating ipv6 2001:DB8::6:6 */
 | |
|                     debug_addr= & debug_sock_addr[1];
 | |
|                     debug_addr->sin6_family= AF_INET6;
 | |
|                     ip6= & debug_addr->sin6_addr;
 | |
|                     ip6->s6_addr[ 0] = 0x20;
 | |
|                     ip6->s6_addr[ 1] = 0x01;
 | |
|                     ip6->s6_addr[ 2] = 0x0d;
 | |
|                     ip6->s6_addr[ 3] = 0xb8;
 | |
|                     ip6->s6_addr[ 4] = 0x00;
 | |
|                     ip6->s6_addr[ 5] = 0x00;
 | |
|                     ip6->s6_addr[ 6] = 0x00;
 | |
|                     ip6->s6_addr[ 7] = 0x00;
 | |
|                     ip6->s6_addr[ 8] = 0x00;
 | |
|                     ip6->s6_addr[ 9] = 0x00;
 | |
|                     ip6->s6_addr[10] = 0x00;
 | |
|                     ip6->s6_addr[11] = 0x00;
 | |
|                     ip6->s6_addr[12] = 0x00;
 | |
|                     ip6->s6_addr[13] = 0x06;
 | |
|                     ip6->s6_addr[14] = 0x00;
 | |
|                     ip6->s6_addr[15] = 0x06;
 | |
| 
 | |
|                     debug_addr_info[0].ai_addr= (struct sockaddr*) & debug_sock_addr[0];
 | |
|                     debug_addr_info[0].ai_addrlen= sizeof (struct sockaddr_in6);
 | |
|                     debug_addr_info[0].ai_next= & debug_addr_info[1];
 | |
| 
 | |
|                     debug_addr_info[1].ai_addr= (struct sockaddr*) & debug_sock_addr[1];
 | |
|                     debug_addr_info[1].ai_addrlen= sizeof (struct sockaddr_in6);
 | |
|                     debug_addr_info[1].ai_next= NULL;
 | |
| 
 | |
|                     addr_info_list= & debug_addr_info[0];
 | |
|                     err_code= 0;
 | |
|                     free_addr_info_list= false;
 | |
|                   }
 | |
|                   );
 | |
| #endif /* HAVE_IPV6 */
 | |
| 
 | |
|   /*
 | |
|   ===========================================================================
 | |
|   DEBUG code only (end)
 | |
|   ===========================================================================
 | |
|   */
 | |
| 
 | |
|   if (err_code != 0)
 | |
|   {
 | |
|     sql_print_warning("Host name '%s' could not be resolved: %s",
 | |
|                       (const char *) hostname_buffer,
 | |
|                       (const char *) gai_strerror(err_code));
 | |
| 
 | |
|     bool validated;
 | |
| 
 | |
|     if (err_code == EAI_NONAME)
 | |
|     {
 | |
|       errors.m_addrinfo_permanent= 1;
 | |
|       validated= true;
 | |
|     }
 | |
|     else
 | |
|     {
 | |
|       /*
 | |
|         Don't cache responses when the DNS server is down, as otherwise
 | |
|         transient DNS failure may leave any number of clients (those
 | |
|         that attempted to connect during the outage) unable to connect
 | |
|         indefinitely.
 | |
|         Only cache error statistics.
 | |
|       */
 | |
|       errors.m_addrinfo_transient= 1;
 | |
|       validated= false;
 | |
|     }
 | |
|     add_hostname(ip_key, NULL, validated, &errors);
 | |
| 
 | |
|     DBUG_RETURN(false);
 | |
|   }
 | |
| 
 | |
|   /* Check that getaddrinfo() returned the used IP (FCrDNS technique). */
 | |
| 
 | |
|   DBUG_PRINT("info", ("The following IP addresses found for '%s':",
 | |
|                       (const char *) hostname_buffer));
 | |
| 
 | |
|   for (struct addrinfo *addr_info= addr_info_list;
 | |
|        addr_info; addr_info= addr_info->ai_next)
 | |
|   {
 | |
|     char ip_buffer[HOST_ENTRY_KEY_SIZE];
 | |
| 
 | |
|     {
 | |
|       err_status=
 | |
|         vio_get_normalized_ip_string(addr_info->ai_addr, (int)addr_info->ai_addrlen,
 | |
|                                      ip_buffer, sizeof (ip_buffer));
 | |
|       DBUG_ASSERT(!err_status);
 | |
|     }
 | |
| 
 | |
|     DBUG_PRINT("info", ("  - '%s'", (const char *) ip_buffer));
 | |
| 
 | |
|     if (strcasecmp(ip_key, ip_buffer) == 0)
 | |
|     {
 | |
|       /* Copy host name string to be stored in the cache. */
 | |
| 
 | |
|       *hostname= my_strdup(key_memory_host_cache_hostname,
 | |
|                            hostname_buffer, MYF(0));
 | |
| 
 | |
|       if (!*hostname)
 | |
|       {
 | |
|         DBUG_PRINT("error", ("Out of memory."));
 | |
| 
 | |
|         if (free_addr_info_list)
 | |
|           freeaddrinfo(addr_info_list);
 | |
|         DBUG_RETURN(true);
 | |
|       }
 | |
| 
 | |
|       break;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   /* Log resolved IP-addresses if no match was found. */
 | |
| 
 | |
|   if (!*hostname)
 | |
|   {
 | |
|     errors.m_FCrDNS= 1;
 | |
| 
 | |
|     sql_print_warning("Hostname '%s' does not resolve to '%s'.",
 | |
|                       (const char *) hostname_buffer,
 | |
|                       (const char *) ip_key);
 | |
|     sql_print_information("Hostname '%s' has the following IP addresses:",
 | |
|                           (const char *) hostname_buffer);
 | |
| 
 | |
|     for (struct addrinfo *addr_info= addr_info_list;
 | |
|          addr_info; addr_info= addr_info->ai_next)
 | |
|     {
 | |
|       char ip_buffer[HOST_ENTRY_KEY_SIZE];
 | |
| 
 | |
|       err_status=
 | |
|         vio_get_normalized_ip_string(addr_info->ai_addr, (int)addr_info->ai_addrlen,
 | |
|                                      ip_buffer, sizeof (ip_buffer));
 | |
|       DBUG_ASSERT(!err_status);
 | |
| 
 | |
|       sql_print_information(" - %s", (const char *) ip_buffer);
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   /* Add an entry for the IP to the cache. */
 | |
|   add_hostname(ip_key, *hostname, true, &errors);
 | |
| 
 | |
|   /* Free the result of getaddrinfo(). */
 | |
|   if (free_addr_info_list)
 | |
|     freeaddrinfo(addr_info_list);
 | |
| 
 | |
|   DBUG_RETURN(false);
 | |
| }
 | 
