Free regular intervals software for linux

Number::Interval is a Perl module that can implement a representation of a numeric interval.

SYNOPSIS

use Number::Interval;

$i = new Number::Interval( Min => -4, Max => 20);
$i = new Number::Interval( Min => 0 );

$is = $i->contains( $value );
$status = $i->intersection( $i2 );

print "$i";

Simple class to implement a closed or open interval. Can be used to compare different intervals, determine set membership, calculate intersections and provide default stringification methods.

Intervals can be bound or unbound. If max is less than min the interval is inverted.

Regular Statement String (RSS) provides several libraries in C, Java, and COM to implement and demonstrate the key-value development method using well-designed "strings" (RSS) as the media. Regular Statement String also shows a way to write "Process Oriented" applications.
Enhancements:
- This release adds an implementation for SUN Solaris (SPARC).

Regular Expression Graphing Program project is a regular expression graphing program.
This program is designed to take a regular expression and produce a graph of the state machine that is used to parse the regular expression.
It is useful for teaching regular expressions and state machines.
The program comes with a built-in tutorial and sample set of regular expressions.
Main features:
- This will not graph all the regular expressions. Some of the more advanced features of the engine are just not handled.
- We currently ``graph the ``group, no $1 (?:..) operator by displaying nothing. A box should be put around the expression.
- The boxes drawn by the program are a fixed with not related to the size of the text they contain. Text can easily overflow the box.
- The system is UNIX/Linux specific. This is caused by only one small section of code should anyone want to port this to a braindamaged operating system.
- Better use of color can be made. Specifically all the nodes do not have to be green. Come to think of it they call dont have to be rectangles either.
- Sometimes the lines connecting one section to another take some strange twists.

RegExplorer project is a regular Expression Explorer.

It allows for writing regular expressions and visually see the matches, thus making regular expression much easier to write and maintain.

Interval arithmetic for Ada is a math library that provides an implementation of intervals for Ada. It includes arithmetic and relational operations.
Examples:
Tri-state logic
The package Intervals serves as a root package and also provides tri-state logic necessary to define relational operations on intervals. The type Logical is defined as:
type Logical is (False, True, Uncertain);
The following operations are defined for Logical:
function "not" (Left : Logical) return Logical;
function "and" (Left, Right : Logical) return Logical;
function "and" (Left : Logical; Right : Boolean)
return Logical;
function "and" (Left : Boolean; Right : Logical)
return Logical;
function "or" (Left, Right : Logical) return Logical;
function "or" (Left : Logical; Right : Boolean)
return Logical;
function "or" (Left : Boolean; Right : Logical)
return Logical;
function "xor" (Left, Right : Logical) return Logical;
function "xor" (Left : Logical; Right : Boolean)
return Logical;
function "xor" (Left : Boolean; Right : Logical)
return Logical;
Enhancements:
- For GNAT users GPS project files were included;
- Based on Measurement units for Ada v 2.4.

GRegExp Explorer is a graphical regular expression explorer based on the PCRE regular expression library. It is possible to test regular expressions on the fly and check the result in detail.

BruteBlock project allows system administrators to block various bruteforce attacks on UNIX services. The program analyzes system logs and adds attackers IP address into ipfw2 table effectively blocking them.

Addresses are automatically removed from the table after specified abound of time. Bruteblock uses regular expressions to parse logs, which gives flexibility allowing it to be used with almost any network service. Bruteblock is written in pure C, doesnt use any external programs and works with ipfw2 tables via raw sockets API.

Installation:
To compile the program run `make` in bruteblock directory. After compilation, copy bruteblock and bruteblockd files into system binary directory (/usr/local/sbin). Copy bruteblock-ssh.conf into directory where configuration files are located (/usr/local/etc) and edit it to make it suit your needs. Edit /etc/syslog.conf and add the following entry:

auth.info;authpriv.info |exec /usr/local/sbin/bruteblock -f /usr/local/etc/bruteblock-ssh.conf

then restart syslogd (/etc/rc.d/syslogd restart). Run bruteblockd, specifying the same ipfw2 table number as in config file (with -t parameter, e.g. # /usr/local/bin/bruteblockd -t 1). Finally, add ipfw rules to block any packets from addresses that match the table, like this:

${fwcmd} add deny ip from me to table(1)
${fwcmd} add deny ip from table(1) to me

Now bruteblock will do its job.

Configuration:
Configuration file for bruteblock utility allows you to set following values:

regexp - regular expression in perl-compatible format that is used to extract failed password attempts from log files.

"regexp0","regexp1",... "regexp9" - optional fields with up to 10 additional regular expressions. max_count, within_time - defines time interval and maximum number of failed password attempts during that interval. If the number is exceeded by specific IP, that IP is blocked.

reset_ip - time-to-live of a block. When it expires, address is removed from table, thus becoming unblocked.

ipfw2_table_no - number of ipfw2 table to add bad IPs to. Must match -t parameter of bruteblockd.