hostname.cc File Reference

Get hostname for an IP address. More...

#include "my_global.h"
#include "sql_priv.h"
#include "hostname.h"
#include "hash_filo.h"
#include <m_ctype.h>
#include "log.h"
#include "violite.h"
#include <sys/utsname.h>

Include dependency graph for hostname.cc:

Go to the source code of this file.

Functions
void	hostname_cache_refresh ()
uint	hostname_cache_size ()
void	hostname_cache_resize (uint size)
bool	hostname_cache_init ()
void	hostname_cache_free ()
void	hostname_cache_lock ()
void	hostname_cache_unlock ()
Host_entry *	hostname_cache_first ()
void	inc_host_errors (const char *ip_string, Host_errors *errors)
void	reset_host_connect_errors (const char *ip_string)
int	ip_to_hostname (struct sockaddr_storage *ip_storage, const char *ip_string, char **hostname, uint *connect_errors)

Variables
ulong	host_cache_size

Detailed Description

Get hostname for an IP address.

Hostnames are checked with reverse name lookup and checked that they doesn't resemble an IP address.

Definition in file hostname.cc.

Function Documentation

int ip_to_hostname	(	struct sockaddr_storage *	ip_storage,
		const char *	ip_string,
		char **	hostname,
		uint *	connect_errors
	)

Resolve IP-address to host name.

This function does the following things:

• resolves IP-address;
• employs Forward Confirmed Reverse DNS technique to validate IP-address;
• returns host name if IP-address is validated;
• set value to out-variable connect_errors – this variable represents the number of connection errors from the specified IP-address.
• update the host_cache statistics

NOTE: connect_errors are counted (are supported) only for the clients where IP-address can be resolved and FCrDNS check is passed.

Parameters

[in]	ip_storage	IP address (sockaddr). Must be set.
[in]	ip_string	IP address (string). Must be set.
[out]	hostname
[out]	connect_errors

Returns

Error status

Return values

0	Success
RC_BLOCKED_HOST	The host is blocked.

The function does not set/report MySQL server error in case of failure. It's caller's responsibility to handle failures of this function properly.

Definition at line 410 of file hostname.cc.

Variable Documentation

ulong host_cache_size

The size of the host_cache.

Definition at line 127 of file hostname.cc.