Merge branch 'parser-snort'

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

diff --git a/modules/Parser.pm b/modules/Parser.pm
index db54cf35f95f2cae7910556ffe297d70df844d50..255e6cc3012aa80e54df13639f2f5d02794e8a07 100644 (file)
--- a/modules/Parser.pm
+++ b/modules/Parser.pm
@@ -9,7 +9,9 @@ our @EXPORT_OK = qw(IsSupportedParser Parser);
 # This hash contains all supported parsers and which function
 # has to be called to parse messages in the right way.
 my %logfile_parsers = (
+       "httpd" => \&message_parser_httpd,
        "snort" => \&message_parser_snort,
+       "ssh" => \&message_parser_ssh,
 );
 
 #
@@ -28,18 +30,16 @@ sub Parser ($$) {
        }
 
        # Call responsible message parser.
-       my $action = $logfile_parsers{$parser}->(@message);
+       my @actions = $logfile_parsers{$parser}->(@message);
 
-       # If the parser successfully parsed the message, an action
-       # has been returned.
-       if ($action) {
-               # Return which action should be performed.
-               return "count $action";
+       # In case an action has been returned, return it too. 
+       if (@actions) {
+               # Return which actions should be performed.
+               return @actions;
        }
 
-       # If the parser was not able to parse the the given message
-       # in the right way, return Nothing.
-       return;
+       # Return undef, if no actions are required.
+       return undef;
 }
 
 #
@@ -125,4 +125,119 @@ sub message_parser_snort(@) {
        return;
 }
 
+#
+## The SSH message parser.
+#
+## This subfunction is used for parsing and detecting different attacks
+## against the SSH service.
+#
+sub message_parser_ssh (@) {
+       my @message = @_;
+       my @actions;
+
+       # The name of the parser module.
+       my $name = "SSH";
+
+       # Variable to store the grabbed IP-address.
+       my $address;
+
+       # Variable to store the parsed event.
+       my $message;
+
+       # Loop through all lines, in case multiple one have
+       # been passed.
+       foreach my $line (@message) {
+               # Check for failed password attempts.
+               if ($line =~/.*sshd.*Failed password for (.*) from (.*) port.*/) {
+                       # Store the grabbed IP-address.
+                       $address = $2;
+
+                       # Set event message.
+                       $message = "Possible SSH-Bruteforce Attack for user: $1.";
+               }
+
+               # This should catch Bruteforce Attacks with enabled preauth
+               elsif ($line =~ /.*sshd.*Received disconnect from (.*):.*\[preauth\]/) {
+                       # Store obtained IP-address.
+                       $address = $1;
+
+                       # Set event message.
+                       $message = "Possible SSH-Bruteforce Attack - failed preauth.";
+               }
+
+               # Check if at least the IP-address information has been extracted.
+               if (defined ($address)) {
+                       # Add the extracted values and event message for the computed
+                       # event to the actions array.
+                       push(@actions, "count $address $name $message");
+               }
+       }
+
+       # If any actions are required, return the array.
+       if (@actions) {
+               return (@actions);
+       }
+
+       # If we got here, the provided message is not affected by any filter and
+       # therefore can be skipped. Return nothing (False) in this case.
+       return;
+}
+
+#
+## The HTTPD message parser.
+#
+## This subfunction is used for parsing and detecting different attacks
+## against a running HTTPD service.
+#
+sub message_parser_httpd (@) {
+       my @message = @_;
+       my @actions;
+
+       # The name of the parser module.
+       my $name = "HTTPD";
+
+       # Variable to store the grabbed IP-address.
+       my $address;
+
+       # Variable to store the parsed event.
+       my $message;
+
+       # Loop through all lines, in case multiple one have
+       # been passed.
+       foreach my $line (@message) {
+               # This will catch brute-force attacks against htaccess logins (username).
+               if ($line =~ /.*\[error\] \[client (.*)\] user(.*) not found:.*/) {
+                       # Store the grabbed IP-address.
+                       $address = $1;
+
+                       # Set event message.
+                       $message = "Possible WUI brute-force attack, wrong user: $2.";
+               }
+
+               # Detect htaccess password brute-forcing against a username.
+               elsif ($line =~ /.*\[error\] \[client (.*)\] user(.*): authentication failure for.*/) {
+                       # Store the extracted IP-address.
+                       $address = $1;
+
+                       # Set event message.
+                       $message = "Possible WUI brute-force attack, wrong password for user: $2.";
+               }
+
+               # Check if at least the IP-address information has been extracted.
+               if (defined ($address)) {
+                       # Add the extracted values and event message to the actions array.
+                       push(@actions, "count $address $name $message");
+               }
+       }
+
+       # If any actions are required, return the array.
+       if (@actions) {
+               return @actions;
+       }
+
+       # If we got here, the provided message is not affected by any filter and
+       # therefore can be skipped. Return nothing (False) in this case.
+       return;
+}
+
 1;