diff -Nur -x bdb mysql-5.0.25-nightly-20060823.host_cache01/client/mysql_priv.h mysql-5.0.25-nightly-20060823.host_cache02/client/mysql_priv.h

--- mysql-5.0.25-nightly-20060823.host_cache01/client/mysql_priv.h 2006-09-25 20:30:47.000000000 -0700

+++ mysql-5.0.25-nightly-20060823.host_cache02/client/mysql_priv.h 2006-09-25 20:32:03.000000000 -0700

@@ -1476,8 +1476,8 @@

/* from hostname.cc */

struct in_addr;

my_string ip_to_hostname(struct in_addr *in,uint *errors);

-void inc_host_errors(struct in_addr *in);

-void reset_host_errors(struct in_addr *in);

+void hostname_cache_inc_errors(struct in_addr *in);

+void hostname_cache_reset_errors(struct in_addr *in);

bool hostname_cache_init();

void hostname_cache_free();

void hostname_cache_refresh(void);

diff -Nur -x bdb mysql-5.0.25-nightly-20060823.host_cache01/sql/hostname.cc mysql-5.0.25-nightly-20060823.host_cache02/sql/hostname.cc

--- mysql-5.0.25-nightly-20060823.host_cache01/sql/hostname.cc 2006-09-25 20:30:47.000000000 -0700

+++ mysql-5.0.25-nightly-20060823.host_cache02/sql/hostname.cc 2006-09-25 21:07:53.000000000 -0700

@@ -16,8 +16,9 @@

/*

- Get hostname for an IP. Hostnames are checked with reverse name lookup and

- checked that they doesn't resemble an ip.

+ Get hostname for an IP. Hostnames are then checked with forward lookup

+ to see that they match the IP address, and checked that they don't

+ resemble an IP address.

*/

#include "mysql_priv.h"

@@ -41,122 +42,230 @@

class host_entry :public hash_filo_element

{

public:

- char ip[sizeof(((struct in_addr *) 0)->s_addr)];

+ uint32 ip;

uint errors;

char *hostname;

};

static hash_filo *hostname_cache;

-static pthread_mutex_t LOCK_hostname;

-void hostname_cache_refresh()

+/*

+ A simple inline function to return the hash key for a given entry.

+*/

+static inline byte *host_entry_get_key(host_entry *entry, uint *length,

+ my_bool not_used __attribute__((unused)))

+ {

+ *length= sizeof(uint32);

+ return (byte *) &entry->ip;

+}

+

+/*

+ A simple inline function to free a hash entry.

+*/

+static inline void host_entry_free_key(host_entry *entry)

{

- hostname_cache->clear();

+ my_free(entry->hostname, MYF(0));

+ my_free((byte *) entry, MYF(0));

}

+

+/*

+ Initializes the hash structure for the hostname cache. Should be

+ called while the server is running single-threaded, before accepting

+ any connections.

+

+ SYNOPSIS

+ hostname_cache_init()

+

+ RETURN

+ 0 ok

+ 1 error

+*/

bool hostname_cache_init()

{

- host_entry tmp;

- uint offset= (uint) ((char*) (&tmp.ip) - (char*) &tmp);

- if (!(hostname_cache=new hash_filo(HOST_CACHE_SIZE, offset,

- sizeof(struct in_addr),NULL,

- (hash_free_key) free,

- &my_charset_bin)))

- return 1;

+ DBUG_ENTER("hostname_cache_init");

+ if (!(hostname_cache= new hash_filo(HOST_CACHE_SIZE, 0, 0,

+ (hash_get_key) host_entry_get_key,

+ (hash_free_key) host_entry_free_key,

+ &my_charset_latin1)))

+ DBUG_RETURN(1);

hostname_cache->clear();

- (void) pthread_mutex_init(&LOCK_hostname,MY_MUTEX_INIT_SLOW);

- return 0;

+ DBUG_RETURN(0);

}

+/*

+ Cleans up the hash structure for the hostname cache. Should be called

+ after stopping accepting connections, before shutting down.

+

+ SYNOPSIS

+ hostname_cache_free()

+*/

void hostname_cache_free()

{

- if (hostname_cache)

- {

- (void) pthread_mutex_destroy(&LOCK_hostname);

- delete hostname_cache;

- hostname_cache= 0;

- }

+ DBUG_ENTER("hostname_cache_free");

+ if (hostname_cache)

+ {

+ delete hostname_cache;

+ hostname_cache= 0;

+ }

+ DBUG_VOID_RETURN;

+}

+

+/*

+ Empty the contents of the hostname cache.

+

+ SYNOPSIS

+ hostname_cache_refresh()

+*/

+void hostname_cache_refresh()

+{

+ DBUG_ENTER("hostname_cache_refresh");

+ hostname_cache->clear();

+ DBUG_VOID_RETURN;

}

+/*

+ Adds an entry in the hostname cache for an IP address stored in 'in'

+ and a hostname 'name'.

-static void add_hostname(struct in_addr *in,const char *name)

+ SYNOPSIS

+ hostname_cache_add(in, name)

+ in pointer to struct in_addr with IP address

+ name string with hostname associated to IP address

+*/

+static void hostname_cache_add(struct in_addr *in, const char *name)

{

- if (!(specialflag & SPECIAL_NO_HOST_CACHE))

- {

+ DBUG_ENTER("hostname_cache_add");

+

+ if (likely(!(specialflag & SPECIAL_NO_HOST_CACHE)))

+ {

VOID(pthread_mutex_lock(&hostname_cache->lock));

host_entry *entry;

- if (!(entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr,0)))

+ if (!(entry= (host_entry*) hostname_cache->search((gptr) &in->s_addr, 0)))

{

- uint length=name ? (uint) strlen(name) : 0;

-

- if ((entry=(host_entry*) malloc(sizeof(host_entry)+length+1)))

+ if ((entry= (host_entry*) my_malloc(sizeof(host_entry),

+ MYF(MY_WME|MY_ZEROFILL))))

{

- char *new_name;

- memcpy_fixed(&entry->ip, &in->s_addr, sizeof(in->s_addr));

- if (length)

- memcpy(new_name= (char *) (entry+1), name, length+1);

- else

- new_name=0;

- entry->hostname=new_name;

- entry->errors=0;

- (void) hostname_cache->add(entry);

- }

- }

- VOID(pthread_mutex_unlock(&hostname_cache->lock));

- }

+ entry->ip = (uint32)in->s_addr;

+ if (name[0] != '\0')

+ entry->hostname= my_strdup(name, MYF(0));

+ (void) hostname_cache->add(entry);

+ }

+ }

+ VOID(pthread_mutex_unlock(&hostname_cache->lock));

+ }

+ DBUG_VOID_RETURN;

}

-

-inline void add_wrong_ip(struct in_addr *in)

+/*

+ Add a denied IP address to the hostname cache, so it can be quickly

+ denied in the future.

+

+ SYNOPSIS

+ hostname_cache_add_deny()

+ in pointer to struct in_addr with IP address

+*/

+inline void hostname_cache_add_deny(struct in_addr *in)

{

- add_hostname(in,NullS);

+ DBUG_ENTER("hostname_cache_add_deny");

+ hostname_cache_add(in, NullS);

+ DBUG_VOID_RETURN;

}

-void inc_host_errors(struct in_addr *in)

+/*

+ Increment the error count for an IP address.

+

+ SYNOPSIS

+ hostname_cache_inc_errors()

+ in pointer to struct in_addr with IP address

+*/

+void hostname_cache_inc_errors(struct in_addr *in)

{

+ DBUG_ENTER("hostname_cache_inc_errors");

+

VOID(pthread_mutex_lock(&hostname_cache->lock));

host_entry *entry;

- if ((entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr,0)))

+ if ((entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr, 0)))

entry->errors++;

VOID(pthread_mutex_unlock(&hostname_cache->lock));

+

+ DBUG_VOID_RETURN;

}

-void reset_host_errors(struct in_addr *in)

+/*

+ Reset the error count for an IP address.

+

+ SYNOPSIS

+ hostname_cache_reset_errors()

+ in pointer to struct in_addr with IP address

+*/

+void hostname_cache_reset_errors(struct in_addr *in)

{

+ DBUG_ENTER("hostname_cache_reset_errors");

+

VOID(pthread_mutex_lock(&hostname_cache->lock));

host_entry *entry;

- if ((entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr,0)))

+ if ((entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr, 0)))

entry->errors=0;

VOID(pthread_mutex_unlock(&hostname_cache->lock));

+

+ DBUG_VOID_RETURN;

}

+

/* Deal with systems that don't defined INADDR_LOOPBACK */

#ifndef INADDR_LOOPBACK

#define INADDR_LOOPBACK 0x7f000001UL

#endif

+/*

+ Double reverse resolve an IP address and return the hostname and

+ a count of errors seen from this IP address. Cache successes

+ and failures using hostname_cache API.

+

+ SYNOPSIS

+ ip_to_hostname()

+ in struct in_addr with IP address to resolve

+ errors pointer to uint to fill in with count of errors

+

+ NOTES

+ - This is called before accepting a connection, so that MySQL

+ has access to the hostname for checking GRANTs.

+ - The results are kept in a cache (hostname_cache) for future

+ lookups.

+

+ RETURN

+ 0 The IP address couldn't be resolved or verified, and a connection

+ shouldn't be accepted from this IP address.

+ * The hostname corresponding to the IP address is returned.

+

+*/

+

my_string ip_to_hostname(struct in_addr *in, uint *errors)

{

- uint i;

- host_entry *entry;

+ char *name;

DBUG_ENTER("ip_to_hostname");

*errors=0;

- /* We always treat the loopback address as "localhost". */

+ /*

+ We always treat the loopback address as "localhost".

+ */

if (in->s_addr == htonl(INADDR_LOOPBACK)) // is expanded inline by gcc

DBUG_RETURN((char *)my_localhost);

- /* Check first if we have name in cache */

+ /*

+ Check the hostname cache for this IP address first.

+ */

if (!(specialflag & SPECIAL_NO_HOST_CACHE))

{

+ host_entry *entry;

VOID(pthread_mutex_lock(&hostname_cache->lock));

- if ((entry=(host_entry*) hostname_cache->search((gptr) &in->s_addr,0)))

+ if ((entry= (host_entry *) hostname_cache->search((gptr) &in->s_addr, 0)))

{

- char *name;

if (!entry->hostname)

- name=0; // Don't allow connection

+ name=0; // Don't allow connection

else

- name=my_strdup(entry->hostname,MYF(0));

+ name=my_strdup(entry->hostname,MYF(0));

*errors= entry->errors;

VOID(pthread_mutex_unlock(&hostname_cache->lock));

DBUG_RETURN(name);

@@ -164,111 +273,113 @@

VOID(pthread_mutex_unlock(&hostname_cache->lock));

}

- struct hostent *hp, *check;

- char *name;

- LINT_INIT(check);

-#if defined(HAVE_GETHOSTBYADDR_R) && defined(HAVE_SOLARIS_STYLE_GETHOST)

- char buff[GETHOSTBYADDR_BUFF_SIZE],buff2[GETHOSTBYNAME_BUFF_SIZE];

+ /*

+ The IP didn't exist in the hostname cache, we need to resolve it.

+ */

+

+ struct hostent *reverse, *forward;

+ struct hostent he_reverse, he_forward;

+ char buf_reverse[GETHOSTBYADDR_BUFF_SIZE];

+ char buf_forward[GETHOSTBYNAME_BUFF_SIZE];

int tmp_errno;

- struct hostent tmp_hostent, tmp_hostent2;

-#ifdef HAVE_purify

- bzero(buff,sizeof(buff)); // Bug in purify

-#endif

- if (!(hp=gethostbyaddr_r((char*) in,sizeof(*in),

- AF_INET,

- &tmp_hostent,buff,sizeof(buff),&tmp_errno)))

- {

- DBUG_PRINT("error",("gethostbyaddr_r returned %d",tmp_errno));

+

+ /*

+ Reverse resolve the IP address.

+ */

+ if (!(reverse= my_gethostbyaddr_r((char*) in, sizeof(*in),

+ AF_INET, &he_reverse,

+ buf_reverse, sizeof(buf_reverse),

+ &tmp_errno)))

+ {

+ DBUG_PRINT("error", ("In reverse lookup: my_gethostbyaddr_r returned %d",

+ tmp_errno));

+ my_gethostbyaddr_r_free();

return 0;

}

- if (!(check=my_gethostbyname_r(hp->h_name,&tmp_hostent2,buff2,sizeof(buff2),

- &tmp_errno)))

+

+ /*

+ Check that we got some hostname back, fail if we got an empty one.

+ */

+ if (!reverse->h_name[0])

+ {

+ DBUG_PRINT("error", ("Got an empty hostname from reverse lookup"));

+ hostname_cache_add_deny(in);

+ my_gethostbyaddr_r_free();

+ DBUG_RETURN(0); // Don't allow empty hostnames

+ }

+

+ /*

+ Copy the hostname we got back, so that we can call my_gethostbyaddr_r_free.

+ */

+ if (!(name= my_strdup(reverse->h_name, MYF(0))))

+ {

+ my_gethostbyaddr_r_free();

+ DBUG_RETURN(0); // out of memory

+ }

+ my_gethostbyaddr_r_free();

+

+ /*

+ Forward resolve the hostname we got from the above reverse resolve.

+ */

+ if (!(forward= my_gethostbyname_r(reverse->h_name, &he_forward,

+ buf_forward, sizeof(buf_forward),

+ &tmp_errno)))

{

- DBUG_PRINT("error",("gethostbyname_r returned %d",tmp_errno));

+ DBUG_PRINT("error", ("In forward lookup: my_gethostbyname_r returned %d",

+ tmp_errno));

/*

- Don't cache responses when the DSN server is down, as otherwise

+ 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.

*/

if (tmp_errno == HOST_NOT_FOUND || tmp_errno == NO_DATA)

- add_wrong_ip(in);

- my_gethostbyname_r_free();

- DBUG_RETURN(0);

- }

- if (!hp->h_name[0])

- {

- DBUG_PRINT("error",("Got an empty hostname"));

- add_wrong_ip(in);

+ hostname_cache_add_deny(in);

+ my_free(name, MYF(0));

my_gethostbyname_r_free();

- DBUG_RETURN(0); // Don't allow empty hostnames

- }

- if (!(name=my_strdup(hp->h_name,MYF(0))))

- {

- my_gethostbyname_r_free();

- DBUG_RETURN(0); // out of memory

- }

- my_gethostbyname_r_free();

-#else

- VOID(pthread_mutex_lock(&LOCK_hostname));

- if (!(hp=gethostbyaddr((char*) in,sizeof(*in), AF_INET)))

- {

- VOID(pthread_mutex_unlock(&LOCK_hostname));

- DBUG_PRINT("error",("gethostbyaddr returned %d",errno));

-

- if (errno == HOST_NOT_FOUND || errno == NO_DATA)

- goto add_wrong_ip_and_return;

- /* Failure, don't cache responce */

- DBUG_RETURN(0);

- }

- if (!hp->h_name[0]) // Don't allow empty hostnames

- {

- VOID(pthread_mutex_unlock(&LOCK_hostname));

- DBUG_PRINT("error",("Got an empty hostname"));

- goto add_wrong_ip_and_return;

- }

- if (!(name=my_strdup(hp->h_name,MYF(0))))

- {

- VOID(pthread_mutex_unlock(&LOCK_hostname));

- DBUG_RETURN(0); // out of memory

- }

- check=gethostbyname(name);

- VOID(pthread_mutex_unlock(&LOCK_hostname));

- if (!check)

- {

- DBUG_PRINT("error",("gethostbyname returned %d",errno));

- my_free(name,MYF(0));

DBUG_RETURN(0);

}

-#endif

- /* Don't accept hostnames that starts with digits because they may be

- false ip:s */

- if (my_isdigit(&my_charset_latin1,name[0]))

+ /*

+ Don't accept hostnames that start with digits because they may be

+ false IP addresses.

+ */

+ if (my_isdigit(&my_charset_latin1, name[0]))

{

char *pos;

- for (pos= name+1 ; my_isdigit(&my_charset_latin1,*pos); pos++) ;

+ for (pos= name+1 ; my_isdigit(&my_charset_latin1, *pos); pos++) ;

if (*pos == '.')

{

- DBUG_PRINT("error",("mysqld doesn't accept hostnames that starts with a number followed by a '.'"));

- my_free(name,MYF(0));

- goto add_wrong_ip_and_return;

+ DBUG_PRINT("error", ("mysqld doesn't accept hostnames that starts with a number followed by a '.'"));

+ goto cache_failure_and_return;

}

}

- /* Check that 'gethostbyname' returned the used ip */

- for (i=0; check->h_addr_list[i]; i++)

+ /*

+ Check that the IP is contained in the list of returned IPs from

+ the forward resolve above. If so, cache it so that we don't have

+ to resolve it again in the future. If not, the connection will be

+ denied after finishing this loop.

+ */

+ for (uint i=0; forward->h_addr_list[i]; i++)

{

- if (*(uint32*)(check->h_addr_list)[i] == in->s_addr)

+ if (*(uint32*)(forward->h_addr_list)[i] == in->s_addr)

{

- add_hostname(in,name);

+ hostname_cache_add(in, name);

+ my_gethostbyname_r_free();

DBUG_RETURN(name);

}

}

- DBUG_PRINT("error",("Couldn't verify hostname with gethostbyname"));

- my_free(name,MYF(0));

-

-add_wrong_ip_and_return:

- add_wrong_ip(in);

+

+ /*

+ Something about this IP address is wrong, and the connection will

+ be denied. In addition, we'll cache this result, so that we can

+ deny future connections from the same IP address much faster.

+ */

+ cache_failure_and_return:

+ DBUG_PRINT("error", ("Double reverse DNS lookup failed for IP, connection will be denied."));

+ my_gethostbyname_r_free();

+ my_free(name, MYF(0));

+ hostname_cache_add_deny(in);

DBUG_RETURN(0);

}

diff -Nur -x bdb mysql-5.0.25-nightly-20060823.host_cache01/sql/mysql_priv.h mysql-5.0.25-nightly-20060823.host_cache02/sql/mysql_priv.h

--- mysql-5.0.25-nightly-20060823.host_cache01/sql/mysql_priv.h 2006-09-25 20:30:47.000000000 -0700

+++ mysql-5.0.25-nightly-20060823.host_cache02/sql/mysql_priv.h 2006-09-25 20:32:03.000000000 -0700

@@ -1476,8 +1476,8 @@

/* from hostname.cc */

struct in_addr;

my_string ip_to_hostname(struct in_addr *in,uint *errors);

-void inc_host_errors(struct in_addr *in);

-void reset_host_errors(struct in_addr *in);

+void hostname_cache_inc_errors(struct in_addr *in);

+void hostname_cache_reset_errors(struct in_addr *in);

bool hostname_cache_init();

void hostname_cache_free();

void hostname_cache_refresh(void);

diff -Nur -x bdb mysql-5.0.25-nightly-20060823.host_cache01/sql/sql_parse.cc mysql-5.0.25-nightly-20060823.host_cache02/sql/sql_parse.cc

--- mysql-5.0.25-nightly-20060823.host_cache01/sql/sql_parse.cc 2006-09-25 20:30:47.000000000 -0700

+++ mysql-5.0.25-nightly-20060823.host_cache02/sql/sql_parse.cc 2006-09-25 20:54:29.000000000 -0700

@@ -366,7 +366,7 @@

if (send_old_password_request(thd) ||

my_net_read(net) != SCRAMBLE_LENGTH_323 + 1)

{

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

DBUG_RETURN(ER_HANDSHAKE_ERROR);

}

/* Final attempt to check the user based on reply */

@@ -925,7 +925,7 @@

(pkt_len= my_net_read(net)) == packet_error ||

pkt_len < MIN_HANDSHAKE_SIZE)

{

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return(ER_HANDSHAKE_ERROR);

}

}

@@ -933,7 +933,7 @@

#include "_cust_sql_parse.h"

#endif

if (connect_errors)

- reset_host_errors(&thd->remote.sin_addr);

+ hostname_cache_reset_errors(&thd->remote.sin_addr);

if (thd->packet.alloc(thd->variables.net_buffer_length))

return(ER_OUT_OF_RESOURCES);

@@ -962,14 +962,14 @@

/* Do the SSL layering. */

if (!ssl_acceptor_fd)

{

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return(ER_HANDSHAKE_ERROR);

}

DBUG_PRINT("info", ("IO layer change in progress..."));

if (sslaccept(ssl_acceptor_fd, net->vio, thd->variables.net_wait_timeout))

{

DBUG_PRINT("error", ("Failed to accept new SSL connection"));

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return(ER_HANDSHAKE_ERROR);

}

DBUG_PRINT("info", ("Reading user information over SSL layer"));

@@ -978,7 +978,7 @@

{

DBUG_PRINT("error", ("Failed to read user information (pkt_len= %lu)",

pkt_len));

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return(ER_HANDSHAKE_ERROR);

}

}

@@ -986,7 +986,7 @@

if (end >= (char*) net->read_pos+ pkt_len +2)

{

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return(ER_HANDSHAKE_ERROR);

}

@@ -1018,7 +1018,7 @@

if (passwd + passwd_len + db_len > (char *)net->read_pos + pkt_len)

{

- inc_host_errors(&thd->remote.sin_addr);

+ hostname_cache_inc_errors(&thd->remote.sin_addr);

return ER_HANDSHAKE_ERROR;

}