[people/stevee/guardian.git] / modules / Events.pm

package Guardian::Events;
use strict;
use warnings;

use Exporter qw(import);

our @EXPORT_OK = qw(Init CheckAction GenerateIgnoreList Update);

# Hash which stores all supported commands from the queue.
my %commands = (
	'count' => \&Counter,
	'block' => \&CallBlock,
	'unblock' => \&CallUnblock,
	'flush' => \&CallFlush,
	'reload' => \&main::Reload,
	'reload-ignore-list' => \&main::ReloadIgnoreList,
	'logrotate' => \&main::Logrotate,
);

# Hash to store addresses and their current count.
my %counthash = ();

# Hash to store all currentyl blocked addresses and a timestamp
# when the block for this address can be released.
my %blockhash = ();

# Hash to store user-defined IP addresses and/or subnets which should be
# ignored in case any events should be repored for them. 
my %ignorehash = ();

# Array to store localhost related IP addresses.
# They are always white-listed to prevent guardian from blocking
# any local traffic.
my @localhost_addresses = ("127.0.0.1", "::1");

# This object will contain the reference to the logger object after calling Init.
my $logger;

#
## The "Init" (Block) function.
#
## This function is responsible to initialize Block as a class based object.
## It has to be called once before any blocking event can be processed.
#
## The following arguments must be passed, during initialization:
## "BlockCount" and "BlockTime" which both have to be natural numbers.
#
sub Init (%) {
	my ( $class, %args ) = @_;
	my $self = \%args;

	# Fail, if some critical arguments are missing.
	unless ((exists($self->{BlockCount})) && (exists($self->{BlockTime}))) {
		die "Could not initialize Block: Too less arguments are given.\n";
	}

	# Use bless to make "$self" to an object of class "$class".
	bless($self, $class);

	# Assign logger object.
	$logger = $self->{Logger};

	# Log used firewall engine.
	$logger->Log("debug", "Using firewall engine: $self->{FirewallEngine}");

	# Try to load the specified firewall engine or die.
	my $module_name = "Guardian::" . $self->{FirewallEngine};
	eval "use $module_name; 1" or die "Could not load a module for firewall engine: $self->{FirewallEngine}!";

	# Check if an IgnoreFile has been configured.
	if (exists($self->{IgnoreFile})) {
		# Call function to handle the ignore mechanism.
	 	&GenerateIgnoreList($self->{IgnoreFile});
	} else {
		# Whitelist local addresses.
		%ignorehash = &_whitelist_localhost();
	}

	# Return the class object.
	return $self;
}

#
## The "Update" Block settings function.
#
## This object based function is called to update various class settings.
#
sub Update (\%) {
        my $self = shift;

	# Dereference the given hash-ref and store
	# the values into a new temporary hash.
	my %settings = %{ $_[0] };

	# Skip settings update if some essential settings are missing.
	unless ((exists($settings{BlockCount})) && (exists($settings{BlockTime}))) {
		$logger->Log("err", "Values for BlockCount or BlockTime are missing, keeping previously configured settings.");

		# Return unmodified class object.
		return $self;
	}

	# Change settings.
        $self->{BlockCount} = $settings{BlockCount};
	$self->{BlockTime} = $settings{BlockTime};

	# Return modified class object.
        return $self;
}

#
## The main "CheckAction" function.
#
## This function is used to handle each recived event from the main event queue of guardian.
#
## It will check if the given command is valid and will pass it to the responsible function.
#
sub CheckAction ($$) {
	my $self = shift;
	my @event = split(/ /, $_[0], 4);
	my ($command, $address, $module, $message) = @event;

	# Check if we got an invalid command.
	unless(exists($commands{$command})) {
                $logger->Log("err", "The CheckAction function has been called with an unsupported command ($command)!");
                return;
        }

	# Check if the given event contains an address.
	if ($address) {
		# Convert and validate the given address.
		my $bin_address = &Guardian::Base::IPOrNet2Int($address);

		# Abort if the given address could not be converted because it is not valid.
		unless ($bin_address) {
			$logger->Log("err", "Invalid IP address: $address");
			return;
		}

		# Check if address should be ignored.
		if(&_IsOnIgnoreList($bin_address)) {
			# Log message.
			$logger->Log("info", "Ignoring event for $address, because it is part of the ignore list.");
			return;
		}
	}

	# Call required handler.
	my $error = $commands{$command}->($self, $address, $module, $message);

	# If we got any return code, something went wrong and should be logged.
	if ($error) {
		$logger->Log("err", "Got error: $error");
		return;
	}
}

#
## The main "Counter" function.
#
## This function is used to handle each count message + address, which has been sent by the main event
## loop of guardian.
#
## It stores the address and the current count into the counthash and increase the count each time when
## the same address should be counted again. When the current count reaches the configured BlockCount,
## the responsible function will be called to block the address.
#
sub Counter ($@) {
	my $self = shift;
	my ($address, $module, $message) = @_;

	# Log event.
	$logger->Log("debug", "$module reported $message for address: $address");

	# Increase existing count or start counting for new source addresses.
	if (exists($counthash{$address})) {
		# Skip already blocked addresses.
		if (exists($blockhash{$address})) {
			return undef;
		}

		# Increase count of the existing entry.
		$counthash{$address} = $counthash{$address} + 1;

		# Log altered count of the address.
		$logger->Log("debug", "Source $address now has count $counthash{$address}/$self->{BlockCount}...");
	} else {
		# Log that counting for the address has been started.
		$logger->Log("debug", "Start counting for $address...");

		# Set count to "1".
		$counthash{$address} = 1;
	}

	# Check if the address has reached the configured count limit.
	if ($counthash{$address} >= $self->{BlockCount}) {
		# Write out log message.
		$logger->Log("info", "Blocking $address for $self->{BlockTime} seconds...");

		# Call block subroutine to block the address.
		my $error = &CallBlock($self, $address, $module, $message);

		# Return the message if an error occurs.
		return $error;
	}

	# Everything worked well, return nothing.
	return undef;
}

#
## The RemoveBlocks function.
#
## This function periodly will be called and is responsible for releasing the block if the Blocktime
## on an address has expired.
#
## To do this, the code will loop through all entries of the blockhash and check
## if the estimiated BlockTime of each address has reached and so the block can be released.
#
sub RemoveBlocks () {
	my $self = shift;

	# Get the current time.
	my $time = time();

	# Loop through the blockhash.
	foreach my $address (keys %blockhash) {
		# Check if the blocktime for the address has expired.
		if ($blockhash{$address} <= $time) {
			# Call unblock subroutine.
			my $error = &CallUnblock($self, $address, "BlockTime", "has expired for $address");

			# Log error messages if returned.
			if ($error) {
				$logger->Log("err", "$error");
			}
		}
	}

	# Everything okay, return nothing.
	return undef;
}

#
## The CallBlock function.
#
## This function is called, if the BlockCount for an address is reached or a direct
## request for blocking an address has been recieved.
#
sub CallBlock ($@) {
	my $self = shift;
	my ($address, $module, $message) = @_;

	# Log the call for blocking an address.
	$logger->Log("info", "$module - $message");

	# Check if an entry for this address exists
	# in the blockhash. If not, the address has
	# not been blocked yet, call the responisible
	# function to do this now.
	unless (exists($blockhash{$address})) {
		# Obtain the configured FirewallAction.
		my $action = $self->{FirewallAction};

		# Block the given address.
		my $error = &DoBlock($address, $action);

		# If we got back an error message something went wrong.
		if ($error) {
			# Exit function and return the used FirewallEngine and the error message.
			return "$self->{FirewallEngine} - $error";
		} else {
			# Address has been successfully blocked, print a log message.
			$logger->Log("debug", "Address $address successfully has been blocked...");
		}
	}

	# Generate time when the block will expire.
	my $expire = time() + $self->{BlockTime};

	# Store the blocked address and the expire time
	# in the blockhash.
	$blockhash{$address} = $expire;

	# Return nothing "undef" if everything is okay.
	return undef;
}

#
## CallUnblock function.
#
## This function is responsible for unblocking and deleting a given
## address from the blockhash.
#
sub CallUnblock ($) {
	my $self = shift;
	my ($address, $module, $message) = @_;

	# Log the call for unblocking an address.
	$logger->Log("info", "$module - $message");

	# Return an error if no entry for the given address
	# is present in the blockhash.
	unless (exists($blockhash{$address})) {
		return "Address $address was not blocked!";
	}

	# Unblock the address.
	my $error = &DoUnblock($address);

	# If an error message is returned, something went wrong.
	if ($error) {
		# Exit function and return the error message.
		return $error;
	} else {
		# Address successfully has been unblocked.
		$logger->Log("debug", "Address $address successfully has been unblocked...");
	}

	# Drop address from blockhash.
	delete ($blockhash{$address});

	# Everything worked well, return nothing.
	return undef;
}

#
## CallFlush function.
#
## This function is responsible for calling the used firewall
## engine to do a flush of the used firewall chain. This will
## clean the entire firewall chain.
#
sub CallFlush ($) {
	my $self = shift;

	# Log the call for flushing.
	$logger->Log("info", "Flush has been called...");

	# Call flush.
	my $error = &DoFlush();

	# If an error message is returned, something went wrong.
	if ($error) {
		# Exit function and return the error message.
		return $error;
	} else {
		# Flush successfully has been performed.
		$logger->Log("debug", "Flush successfully has been performed...");
	}

	# Flush blockhash.
	%blockhash = ();

	# Everything worked well, return nothing.
	return undef;
}

#
## GenerateIgnoreList function.
#
## This function is responsible for generating/updating the
## IgnoreHash which contains all ignored IP addresses and
## networks.
#
sub GenerateIgnoreList($) {
	my $file = shift;
	my @include_files;

	# Reset current ignore hash and add
	# localhost related IP addresses.
	%ignorehash = &_whitelist_localhost();

	# Check if the given IgnoreFile could be opened.
	unless(-e $file) {
		$logger->Log("err", "The configured IgnoreFile \($file\) could not be opened. Skipped!");
		return;
	}

	# Open the given IgnoreFile.
	open (IGNORE, $file);

	# Read-in the file line by line.
	while (<IGNORE>) {
		# Skip comments.
		next if (/\#/);

		# Skip blank lines.
		next if (/^\s*$/);

		# Remove any newlines.
		chomp;

		# Check for an include instruction.
		if ($_ =~ /^Include_File = (.*)/) {
			my $include_file = $1;

			# Check if the parsed include file exists and is read-able.
			if (-e $include_file) {
				# Add file to the array of files wich will be included.
				push(@include_files, $include_file);

				# Write out log message.
				$logger->Log("debug", "Addresses from $include_file will be included...");
			} else {
				# Log missing file.
				$logger->Log("err", "$include_file will not be included. File does not exist!");
			}
		} else {
			# Check if the line contains a valid single address or network and
			# convert it into binary format. Store the result/start and
			# end values in a temporary array.
			my @values = &Guardian::Base::IPOrNet2Int($_);

			# If the function returned any values, the line contained a valid
			# single address or network which successfully has been converted into
			# binary format.
			if (@values) {
				# Assign the array as value to the ignorehash.
				$ignorehash{$_} = [@values];
			} else {
				# Log invalid entry.
				$logger->Log("err", "IgnoreFile contains an invalid address/network: $_");

				# Skip line.
				next;
			}
		}
	}

	# Close filehandle for the IgnoreFile.
	close (IGNORE);

	# Check if any files should be included.
	if (@include_files) {
		# Loop through the array of files which should be included.
		foreach my $file (@include_files) {
			# Open the file.
			open(INCLUDE, $file);

			# Read-in file line by line.
			while(<INCLUDE>) {
				# Skip any comments.
				next if (/\#/);

				# Skip any blank lines.
				next if (/^\s*$/);

				# Chomp any newlines.
				chomp;

				# Check if the line contains a valid single address or network and
				# convert it into binary format. Store the result/start and
				# end values in a temporary array.
				my @values = &Guardian::Base::IPOrNet2Int($_);

				# If the function returned any values, the line contained a valid
				# single address or network which successfully has been converted into
				# binary format.
				if (@values) {
					# Assign the array as value to the ignorehash.
					$ignorehash{$_} = [@values];
				} else {
					# Log invalid entry.
					$logger->Log("err", "$file contains an invalid address/network: $_");

					# Skip line.
					next;
				}
			}

			# Close filehandle.
			close(INCLUDE);
		}
	}

	# Get amount of current elements in hash.
	my $amount = scalar(keys(%ignorehash));

	# Write out log message.
	$logger->Log("debug", "Ignore list currently contains $amount entries.");
}

#
## Private function to check if an address is part of the Ignore Hash.
#
## This function checks if a passed IP address in binary format (!),
## directly or as part of an ignored network is stored in the ignore hash.
#
sub _IsOnIgnoreList ($) {
	my $bin_address = shift;

	# Loop through the ignore hash and grab the stored values.
	foreach my $key ( keys %ignorehash ) {
		# Dereference values array.
		my @values = @{$ignorehash{$key}};

		# Obtain amount of items for the current value array.
		my $items = scalar @values;

		# Whether the amount equals one, the given binary address just
		# needs to be compared against a single address.
		if ($items eq "1") {
			my ($ignored_address) = @values;

			# Simple check if the stored and the given binary address
			# are the same.
			if ($bin_address eq $ignored_address) {
				# The given address is part of the ignore list.
				$logger->Log("debug", "Address $key found on the ignore list.");

				# Return "1" (True).
				return 1;
			}
		}

		# If the amount equals two, for passed binary address needs to
		# be checked if it is part of the ignored network range.
		elsif ($items eq "2") {
			my ($first_address, $last_address) = @values;

			# Check if the passed binary address is bigger than
			# the first address and smaler than the last address
			# (between) the stored network range.
			if (($bin_address >= $first_address) && ($bin_address <= $last_address)) {
				# The address is part of an ignored network.
				$logger->Log("debug", "Address is found inside the ignored network $key.");

				# Return "1" (True).
				return 1;
			}

		# If the amount is not eighter one or two, the current entry of the ignorehash seems
		# to be corrupted. Skip and log it.
		} else {
			# Write log message about this corruped item in the ignore hash.
			$logger->Log("err", "Invalid item in the Ignore Hash: $key - @values");

			# Skip this element of the ignore hash.
			next;
		}
	}

	# If we got here, the given address is not part of the ignore hash.
	# Return nothing (False).
	return;
}

#
## The _whitelist_localhost function.
#
## This tiny private function simple generates and returns a hash which contains
## the clear and binary converted addresses for all array-stored
## (@localhost_addresses) in an ignorelist compatible format.
#
sub _whitelist_localhost () {
	my %temphash;

	# Loop through the array of localhost related addresses.
	foreach my $address (@localhost_addresses) {
		# Validate and convert the addresss into binary format.
		my @values = &Guardian::Base::IPOrNet2Int($address);

		# Check if any values are returned.
		if (@values) {
			# Store the converted binary values in the temporary hash.
			$temphash{$address} = [@values];
		}
	}

	# Return the temporary hash.
	return %temphash;
}

1;
Commit	Line	Data
df6ec59f SS	1	package Guardian::Events;
	2	use strict;
	3	use warnings;
	4
	5	use Exporter qw(import);
	6
7c8f0696	7	our @EXPORT_OK = qw(Init CheckAction GenerateIgnoreList Update);
df6ec59f SS	8
	9	# Hash which stores all supported commands from the queue.
	10	my %commands = (
	11	'count' => \&Counter,
	12	'block' => \&CallBlock,
	13	'unblock' => \&CallUnblock,
	14	'flush' => \&CallFlush,
7121d8cd	15	'reload' => \&main::Reload,
ab7c10eb	16	'reload-ignore-list' => \&main::ReloadIgnoreList,
648ca493	17	'logrotate' => \&main::Logrotate,
df6ec59f SS	18	);
	19
	20	# Hash to store addresses and their current count.
	21	my %counthash = ();
	22
	23	# Hash to store all currentyl blocked addresses and a timestamp
	24	# when the block for this address can be released.
	25	my %blockhash = ();
	26
66e1ad0a	27	# Hash to store user-defined IP addresses and/or subnets which should be
0d218038	28	# ignored in case any events should be repored for them.
66e1ad0a SS	29	my %ignorehash = ();
66e1ad0a SS	30
0d218038 SS	31	# Array to store localhost related IP addresses.
	32	# They are always white-listed to prevent guardian from blocking
	33	# any local traffic.
	34	my @localhost_addresses = ("127.0.0.1", "::1");
	35
df6ec59f SS	36	# This object will contain the reference to the logger object after calling Init.
	37	my $logger;
	38
	39	#
	40	## The "Init" (Block) function.
	41	#
	42	## This function is responsible to initialize Block as a class based object.
	43	## It has to be called once before any blocking event can be processed.
	44	#
	45	## The following arguments must be passed, during initialization:
	46	## "BlockCount" and "BlockTime" which both have to be natural numbers.
	47	#
	48	sub Init (%) {
	49	my ( $class, %args ) = @_;
	50	my $self = \%args;
	51
	52	# Fail, if some critical arguments are missing.
	53	unless ((exists($self->{BlockCount})) && (exists($self->{BlockTime}))) {
	54	die "Could not initialize Block: Too less arguments are given.\n";
	55	}
	56
	57	# Use bless to make "$self" to an object of class "$class".
	58	bless($self, $class);
	59
	60	# Assign logger object.
	61	$logger = $self->{Logger};
	62
	63	# Log used firewall engine.
	64	$logger->Log("debug", "Using firewall engine: $self->{FirewallEngine}");
	65
	66	# Try to load the specified firewall engine or die.
	67	my $module_name = "Guardian::" . $self->{FirewallEngine};
	68	eval "use $module_name; 1" or die "Could not load a module for firewall engine: $self->{FirewallEngine}!";
	69
66e1ad0a SS	70	# Check if an IgnoreFile has been configured.
	71	if (exists($self->{IgnoreFile})) {
	72	# Call function to handle the ignore mechanism.
	73	&GenerateIgnoreList($self->{IgnoreFile});
0d218038 SS	74	} else {
	75	# Whitelist local addresses.
	76	%ignorehash = &_whitelist_localhost();
66e1ad0a SS	77	}
66e1ad0a SS	78
df6ec59f SS	79	# Return the class object.
	80	return $self;
	81	}
	82
10442560 SS	83	#
	84	## The "Update" Block settings function.
	85	#
	86	## This object based function is called to update various class settings.
	87	#
	88	sub Update (\%) {
	89	my $self = shift;
	90
	91	# Dereference the given hash-ref and store
	92	# the values into a new temporary hash.
	93	my %settings = %{ $_[0] };
	94
	95	# Skip settings update if some essential settings are missing.
	96	unless ((exists($settings{BlockCount})) && (exists($settings{BlockTime}))) {
	97	$logger->Log("err", "Values for BlockCount or BlockTime are missing, keeping previously configured settings.");
	98
	99	# Return unmodified class object.
	100	return $self;
	101	}
	102
	103	# Change settings.
	104	$self->{BlockCount} = $settings{BlockCount};
	105	$self->{BlockTime} = $settings{BlockTime};
	106
	107	# Return modified class object.
	108	return $self;
	109	}
	110
df6ec59f SS	111	#
	112	## The main "CheckAction" function.
	113	#
	114	## This function is used to handle each recived event from the main event queue of guardian.
	115	#
	116	## It will check if the given command is valid and will pass it to the responsible function.
	117	#
	118	sub CheckAction ($$) {
	119	my $self = shift;
	120	my @event = split(/ /, $_[0], 4);
	121	my ($command, $address, $module, $message) = @event;
	122
	123	# Check if we got an invalid command.
	124	unless(exists($commands{$command})) {
	125	$logger->Log("err", "The CheckAction function has been called with an unsupported command ($command)!");
	126	return;
	127	}
	128
e1ff25ce SS	129	# Check if the given event contains an address.
	130	if ($address) {
	131	# Convert and validate the given address.
	132	my $bin_address = &Guardian::Base::IPOrNet2Int($address);
	133
	134	# Abort if the given address could not be converted because it is not valid.
	135	unless ($bin_address) {
	136	$logger->Log("err", "Invalid IP address: $address");
	137	return;
	138	}
	139
	140	# Check if address should be ignored.
	141	if(&_IsOnIgnoreList($bin_address)) {
	142	# Log message.
	143	$logger->Log("info", "Ignoring event for $address, because it is part of the ignore list.");
	144	return;
	145	}
66e1ad0a SS	146	}
66e1ad0a SS	147
df6ec59f SS	148	# Call required handler.
	149	my $error = $commands{$command}->($self, $address, $module, $message);
	150
	151	# If we got any return code, something went wrong and should be logged.
	152	if ($error) {
	153	$logger->Log("err", "Got error: $error");
	154	return;
	155	}
	156	}
	157
	158	#
	159	## The main "Counter" function.
	160	#
	161	## This function is used to handle each count message + address, which has been sent by the main event
	162	## loop of guardian.
	163	#
	164	## It stores the address and the current count into the counthash and increase the count each time when
	165	## the same address should be counted again. When the current count reaches the configured BlockCount,
	166	## the responsible function will be called to block the address.
	167	#
	168	sub Counter ($@) {
	169	my $self = shift;
	170	my ($address, $module, $message) = @_;
	171
	172	# Log event.
	173	$logger->Log("debug", "$module reported $message for address: $address");
	174
	175	# Increase existing count or start counting for new source addresses.
	176	if (exists($counthash{$address})) {
	177	# Skip already blocked addresses.
	178	if (exists($blockhash{$address})) {
	179	return undef;
	180	}
	181
	182	# Increase count of the existing entry.
	183	$counthash{$address} = $counthash{$address} + 1;
	184
	185	# Log altered count of the address.
	186	$logger->Log("debug", "Source $address now has count $counthash{$address}/$self->{BlockCount}...");
	187	} else {
	188	# Log that counting for the address has been started.
	189	$logger->Log("debug", "Start counting for $address...");
	190
	191	# Set count to "1".
	192	$counthash{$address} = 1;
	193	}
	194
	195	# Check if the address has reached the configured count limit.
	196	if ($counthash{$address} >= $self->{BlockCount}) {
	197	# Write out log message.
	198	$logger->Log("info", "Blocking $address for $self->{BlockTime} seconds...");
	199
	200	# Call block subroutine to block the address.
	201	my $error = &CallBlock($self, $address, $module, $message);
	202
	203	# Return the message if an error occurs.
	204	return $error;
	205	}
	206
	207	# Everything worked well, return nothing.
	208	return undef;
	209	}
	210
	211	#
212	## The RemoveBlocks function.
213	#
214	## This function periodly will be called and is responsible for releasing the block if the Blocktime
215	## on an address has expired.
216	#
217	## To do this, the code will loop through all entries of the blockhash and check
218	## if the estimiated BlockTime of each address has reached and so the block can be released.
219	#
220	sub RemoveBlocks () {
221	my $self = shift;
222
223	# Get the current time.
224	my $time = time();
225
226	# Loop through the blockhash.
227	foreach my $address (keys %blockhash) {
228	# Check if the blocktime for the address has expired.
229	if ($blockhash{$address} <= $time) {
230	# Call unblock subroutine.
231	my $error = &CallUnblock($self, $address, "BlockTime", "has expired for $address");
232
233	# Log error messages if returned.
234	if ($error) {
235	$logger->Log("err", "$error");
236	}
237	}
238	}
239
240	# Everything okay, return nothing.
241	return undef;
242	}
243
244	#
245	## The CallBlock function.
246	#
247	## This function is called, if the BlockCount for an address is reached or a direct
248	## request for blocking an address has been recieved.
249	#
250	sub CallBlock ($@) {
251	my $self = shift;
252	my ($address, $module, $message) = @_;
253
254	# Log the call for blocking an address.
255	$logger->Log("info", "$module - $message");
256
257	# Check if an entry for this address exists
258	# in the blockhash. If not, the address has
259	# not been blocked yet, call the responisible
260	# function to do this now.
261	unless (exists($blockhash{$address})) {
e9c558fe SS	262	# Obtain the configured FirewallAction.
e9c558fe SS	263	my $action = $self->{FirewallAction};
df6ec59f SS	264
	265	# Block the given address.
	266	my $error = &DoBlock($address, $action);
	267
	268	# If we got back an error message something went wrong.
	269	if ($error) {
f842727a SS	270	# Exit function and return the used FirewallEngine and the error message.
f842727a SS	271	return "$self->{FirewallEngine} - $error";
df6ec59f SS	272	} else {
	273	# Address has been successfully blocked, print a log message.
	274	$logger->Log("debug", "Address $address successfully has been blocked...");
	275	}
	276	}
	277
	278	# Generate time when the block will expire.
	279	my $expire = time() + $self->{BlockTime};
	280
	281	# Store the blocked address and the expire time
	282	# in the blockhash.
	283	$blockhash{$address} = $expire;
	284
	285	# Return nothing "undef" if everything is okay.
	286	return undef;
	287	}
	288
	289	#
	290	## CallUnblock function.
	291	#
	292	## This function is responsible for unblocking and deleting a given
	293	## address from the blockhash.
	294	#
	295	sub CallUnblock ($) {
	296	my $self = shift;
	297	my ($address, $module, $message) = @_;
	298
	299	# Log the call for unblocking an address.
	300	$logger->Log("info", "$module - $message");
	301
	302	# Return an error if no entry for the given address
	303	# is present in the blockhash.
	304	unless (exists($blockhash{$address})) {
	305	return "Address $address was not blocked!";
	306	}
	307
	308	# Unblock the address.
	309	my $error = &DoUnblock($address);
	310
	311	# If an error message is returned, something went wrong.
	312	if ($error) {
	313	# Exit function and return the error message.
	314	return $error;
	315	} else {
	316	# Address successfully has been unblocked.
	317	$logger->Log("debug", "Address $address successfully has been unblocked...");
	318	}
	319
	320	# Drop address from blockhash.
	321	delete ($blockhash{$address});
	322
	323	# Everything worked well, return nothing.
	324	return undef;
	325	}
	326
7c96d150 SS	327	#
	328	## CallFlush function.
	329	#
	330	## This function is responsible for calling the used firewall
	331	## engine to do a flush of the used firewall chain. This will
	332	## clean the entire firewall chain.
	333	#
	334	sub CallFlush ($) {
	335	my $self = shift;
	336
	337	# Log the call for flushing.
	338	$logger->Log("info", "Flush has been called...");
	339
	340	# Call flush.
	341	my $error = &DoFlush();
	342
	343	# If an error message is returned, something went wrong.
	344	if ($error) {
	345	# Exit function and return the error message.
	346	return $error;
	347	} else {
	348	# Flush successfully has been performed.
	349	$logger->Log("debug", "Flush successfully has been performed...");
	350	}
	351
	352	# Flush blockhash.
	353	%blockhash = ();
	354
	355	# Everything worked well, return nothing.
	356	return undef;
	357	}
	358
66e1ad0a SS	359	#
	360	## GenerateIgnoreList function.
	361	#
	362	## This function is responsible for generating/updating the
	363	## IgnoreHash which contains all ignored IP addresses and
	364	## networks.
	365	#
	366	sub GenerateIgnoreList($) {
	367	my $file = shift;
900cad7f SS	368	my @include_files;
	369
	370	# Reset current ignore hash and add
	371	# localhost related IP addresses.
	372	%ignorehash = &_whitelist_localhost();
66e1ad0a SS	373
	374	# Check if the given IgnoreFile could be opened.
	375	unless(-e $file) {
	376	$logger->Log("err", "The configured IgnoreFile \($file\) could not be opened. Skipped!");
	377	return;
	378	}
	379
900cad7f	380	# Open the given IgnoreFile.
66e1ad0a SS	381	open (IGNORE, $file);
	382
	383	# Read-in the file line by line.
	384	while (<IGNORE>) {
	385	# Skip comments.
	386	next if (/\#/);
	387
	388	# Skip blank lines.
	389	next if (/^\s*$/);
	390
	391	# Remove any newlines.
	392	chomp;
	393
900cad7f SS	394	# Check for an include instruction.
	395	if ($_ =~ /^Include_File = (.*)/) {
	396	my $include_file = $1;
66e1ad0a	397
900cad7f SS	398	# Check if the parsed include file exists and is read-able.
	399	if (-e $include_file) {
	400	# Add file to the array of files wich will be included.
	401	push(@include_files, $include_file);
	402
	403	# Write out log message.
	404	$logger->Log("debug", "Addresses from $include_file will be included...");
	405	} else {
	406	# Log missing file.
	407	$logger->Log("err", "$include_file will not be included. File does not exist!");
	408	}
	409	} else {
	410	# Check if the line contains a valid single address or network and
	411	# convert it into binary format. Store the result/start and
	412	# end values in a temporary array.
	413	my @values = &Guardian::Base::IPOrNet2Int($_);
	414
	415	# If the function returned any values, the line contained a valid
	416	# single address or network which successfully has been converted into
	417	# binary format.
	418	if (@values) {
	419	# Assign the array as value to the ignorehash.
	420	$ignorehash{$_} = [@values];
	421	} else {
	422	# Log invalid entry.
	423	$logger->Log("err", "IgnoreFile contains an invalid address/network: $_");
	424
	425	# Skip line.
	426	next;
	427	}
66e1ad0a SS	428	}
	429	}
	430
	431	# Close filehandle for the IgnoreFile.
	432	close (IGNORE);
5cd378cd	433
900cad7f SS	434	# Check if any files should be included.
	435	if (@include_files) {
	436	# Loop through the array of files which should be included.
	437	foreach my $file (@include_files) {
	438	# Open the file.
	439	open(INCLUDE, $file);
	440
	441	# Read-in file line by line.
	442	while(<INCLUDE>) {
	443	# Skip any comments.
	444	next if (/\#/);
	445
	446	# Skip any blank lines.
	447	next if (/^\s*$/);
	448
	449	# Chomp any newlines.
	450	chomp;
	451
	452	# Check if the line contains a valid single address or network and
	453	# convert it into binary format. Store the result/start and
	454	# end values in a temporary array.
	455	my @values = &Guardian::Base::IPOrNet2Int($_);
	456
	457	# If the function returned any values, the line contained a valid
	458	# single address or network which successfully has been converted into
	459	# binary format.
	460	if (@values) {
	461	# Assign the array as value to the ignorehash.
	462	$ignorehash{$_} = [@values];
	463	} else {
	464	# Log invalid entry.
	465	$logger->Log("err", "$file contains an invalid address/network: $_");
	466
	467	# Skip line.
	468	next;
	469	}
	470	}
	471
	472	# Close filehandle.
	473	close(INCLUDE);
	474	}
	475	}
	476
5cd378cd SS	477	# Get amount of current elements in hash.
	478	my $amount = scalar(keys(%ignorehash));
	479
	480	# Write out log message.
	481	$logger->Log("debug", "Ignore list currently contains $amount entries.");
66e1ad0a SS	482	}
	483
	484	#
	485	## Private function to check if an address is part of the Ignore Hash.
	486	#
7c8f0696 SS	487	## This function checks if a passed IP address in binary format (!),
7c8f0696 SS	488	## directly or as part of an ignored network is stored in the ignore hash.
66e1ad0a SS	489	#
	490	sub _IsOnIgnoreList ($) {
	491	my $bin_address = shift;
	492
	493	# Loop through the ignore hash and grab the stored values.
	494	foreach my $key ( keys %ignorehash ) {
	495	# Dereference values array.
	496	my @values = @{$ignorehash{$key}};
	497
	498	# Obtain amount of items for the current value array.
	499	my $items = scalar @values;
	500
	501	# Whether the amount equals one, the given binary address just
	502	# needs to be compared against a single address.
	503	if ($items eq "1") {
	504	my ($ignored_address) = @values;
	505
	506	# Simple check if the stored and the given binary address
	507	# are the same.
	508	if ($bin_address eq $ignored_address) {
	509	# The given address is part of the ignore list.
	510	$logger->Log("debug", "Address $key found on the ignore list.");
	511
	512	# Return "1" (True).
	513	return 1;
	514	}
	515	}
	516
	517	# If the amount equals two, for passed binary address needs to
	518	# be checked if it is part of the ignored network range.
	519	elsif ($items eq "2") {
	520	my ($first_address, $last_address) = @values;
	521
	522	# Check if the passed binary address is bigger than
	523	# the first address and smaler than the last address
	524	# (between) the stored network range.
	525	if (($bin_address >= $first_address) && ($bin_address <= $last_address)) {
	526	# The address is part of an ignored network.
	527	$logger->Log("debug", "Address is found inside the ignored network $key.");
	528
	529	# Return "1" (True).
	530	return 1;
	531	}
	532
	533	# If the amount is not eighter one or two, the current entry of the ignorehash seems
	534	# to be corrupted. Skip and log it.
	535	} else {
	536	# Write log message about this corruped item in the ignore hash.
	537	$logger->Log("err", "Invalid item in the Ignore Hash: $key - @values");
	538
	539	# Skip this element of the ignore hash.
	540	next;
	541	}
	542	}
	543
	544	# If we got here, the given address is not part of the ignore hash.
	545	# Return nothing (False).
	546	return;
	547	}
	548
0d218038 SS	549	#
	550	## The _whitelist_localhost function.
	551	#
	552	## This tiny private function simple generates and returns a hash which contains
	553	## the clear and binary converted addresses for all array-stored
	554	## (@localhost_addresses) in an ignorelist compatible format.
	555	#
	556	sub _whitelist_localhost () {
	557	my %temphash;
	558
	559	# Loop through the array of localhost related addresses.
	560	foreach my $address (@localhost_addresses) {
	561	# Validate and convert the addresss into binary format.
	562	my @values = &Guardian::Base::IPOrNet2Int($address);
	563
	564	# Check if any values are returned.
	565	if (@values) {
	566	# Store the converted binary values in the temporary hash.
	567	$temphash{$address} = [@values];
	568	}
	569	}
	570
	571	# Return the temporary hash.
	572	return %temphash;
	573	}
	574
df6ec59f	575	1;