1 /* Copyright (c) 2006, 2011, Oracle and/or its affiliates. All rights reserved.
2 
3    This program is free software; you can redistribute it and/or modify
4    it under the terms of the GNU General Public License as published by
5    the Free Software Foundation; version 2 of the License.
6 
7    This program is distributed in the hope that it will be useful,
8    but WITHOUT ANY WARRANTY; without even the implied warranty of
9    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10    GNU General Public License for more details.
11 
12    You should have received a copy of the GNU General Public License
13    along with this program; if not, write to the Free Software
14    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1335  USA */
15 
16 #ifndef HOSTNAME_INCLUDED
17 #define HOSTNAME_INCLUDED
18 
19 #include "my_net.h"
20 #include "hash_filo.h"
21 
22 struct Host_errors
23 {
24 public:
25   Host_errors();
26   ~Host_errors();
27 
28   void reset();
29   void aggregate(const Host_errors *errors);
30 
31   /** Number of connect errors. */
32   ulong m_connect;
33 
34   /** Number of host blocked errors. */
35   ulong m_host_blocked;
36   /** Number of transient errors from getnameinfo(). */
37   ulong m_nameinfo_transient;
38   /** Number of permanent errors from getnameinfo(). */
39   ulong m_nameinfo_permanent;
40   /** Number of errors from is_hostname_valid(). */
41   ulong m_format;
42   /** Number of transient errors from getaddrinfo(). */
43   ulong m_addrinfo_transient;
44   /** Number of permanent errors from getaddrinfo(). */
45   ulong m_addrinfo_permanent;
46   /** Number of errors from Forward-Confirmed reverse DNS checks. */
47   ulong m_FCrDNS;
48   /** Number of errors from host grants. */
49   ulong m_host_acl;
50   /** Number of errors from missing auth plugin. */
51   ulong m_no_auth_plugin;
52   /** Number of errors from auth plugin. */
53   ulong m_auth_plugin;
54   /** Number of errors from authentication plugins. */
55   ulong m_handshake;
56   /** Number of errors from proxy user. */
57   ulong m_proxy_user;
58   /** Number of errors from proxy user acl. */
59   ulong m_proxy_user_acl;
60   /** Number of errors from authentication. */
61   ulong m_authentication;
62   /** Number of errors from ssl. */
63   ulong m_ssl;
64   /** Number of errors from max user connection. */
65   ulong m_max_user_connection;
66   /** Number of errors from max user connection per hour. */
67   ulong m_max_user_connection_per_hour;
68   /** Number of errors from the default database. */
69   ulong m_default_database;
70   /** Number of errors from init_connect. */
71   ulong m_init_connect;
72   /** Number of errors from the server itself. */
73   ulong m_local;
74 
has_errorHost_errors75   bool has_error() const
76   {
77     return ((m_host_blocked != 0)
78       || (m_nameinfo_transient != 0)
79       || (m_nameinfo_permanent != 0)
80       || (m_format != 0)
81       || (m_addrinfo_transient != 0)
82       || (m_addrinfo_permanent != 0)
83       || (m_FCrDNS != 0)
84       || (m_host_acl != 0)
85       || (m_no_auth_plugin != 0)
86       || (m_auth_plugin != 0)
87       || (m_handshake != 0)
88       || (m_proxy_user != 0)
89       || (m_proxy_user_acl != 0)
90       || (m_authentication != 0)
91       || (m_ssl != 0)
92       || (m_max_user_connection != 0)
93       || (m_max_user_connection_per_hour != 0)
94       || (m_default_database != 0)
95       || (m_init_connect != 0)
96       || (m_local != 0));
97   }
98 
sum_connect_errorsHost_errors99   void sum_connect_errors()
100   {
101     /* Current (historical) behavior: */
102     m_connect= m_handshake;
103   }
104 
clear_connect_errorsHost_errors105   void clear_connect_errors()
106   {
107     m_connect= 0;
108   }
109 };
110 
111 /** Size of IP address string in the hash cache. */
112 #define HOST_ENTRY_KEY_SIZE INET6_ADDRSTRLEN
113 
114 /**
115   An entry in the hostname hash table cache.
116 
117   Host name cache does two things:
118     - caches host names to save DNS look ups;
119     - counts errors from IP.
120 
121   Host name can be empty (that means DNS look up failed),
122   but errors still are counted.
123 */
124 class Host_entry : public hash_filo_element
125 {
126 public:
next()127   Host_entry *next()
128   { return (Host_entry*) hash_filo_element::next(); }
129 
130   /**
131     Client IP address. This is the key used with the hash table.
132 
133     The client IP address is always expressed in IPv6, even when the
134     network IPv6 stack is not present.
135 
136     This IP address is never used to connect to a socket.
137   */
138   char ip_key[HOST_ENTRY_KEY_SIZE];
139 
140   /**
141     One of the host names for the IP address. May be a zero length string.
142   */
143   char m_hostname[HOSTNAME_LENGTH + 1];
144   /** Length in bytes of @c m_hostname. */
145   uint m_hostname_length;
146   /** The hostname is validated and used for authorization. */
147   bool m_host_validated;
148   ulonglong m_first_seen;
149   ulonglong m_last_seen;
150   ulonglong m_first_error_seen;
151   ulonglong m_last_error_seen;
152   /** Error statistics. */
153   Host_errors m_errors;
154 
set_error_timestamps(ulonglong now)155   void set_error_timestamps(ulonglong now)
156   {
157     if (m_first_error_seen == 0)
158       m_first_error_seen= now;
159     m_last_error_seen= now;
160   }
161 };
162 
163 /** The size of the host_cache. */
164 extern ulong host_cache_size;
165 
166 #define RC_OK 0
167 #define RC_BLOCKED_HOST 1
168 int ip_to_hostname(struct sockaddr_storage *ip_storage,
169                    const char *ip_string,
170                    const char **hostname, uint *connect_errors);
171 
172 void inc_host_errors(const char *ip_string, Host_errors *errors);
173 void reset_host_connect_errors(const char *ip_string);
174 bool hostname_cache_init();
175 void hostname_cache_free();
176 void hostname_cache_refresh(void);
177 uint hostname_cache_size();
178 void hostname_cache_resize(uint size);
179 void hostname_cache_lock();
180 void hostname_cache_unlock();
181 Host_entry *hostname_cache_first();
182 
183 #endif /* HOSTNAME_INCLUDED */
184