AIDE (Advanced Intrusion Detection Environment) is a file and directory integrity checker. It creates a database from the regular expression rules that it finds from the config file. Once this database is initialized it can be used to verify the integrity of the files. Several message digest algorithms are used. All of the usual file attributes can also be checked for inconsistencies.
AMaViS (A Mail Virus Scanner) scans e-mail attachments for viruses using third-party virus scanners available for UNIX environments. It resides on a UNIX (Linux) machine and looks through the attached files arriving via e-mail, generates reports when a virus is found and sets the delivery on hold.
Angst is an active sniffer, based on libpcap and libnet. It dumps into a file the payload of all the TCP packets received on the specified ports. It implements two methods for active sniffing. Angst is able to monitor ARP requests, and after enabling IP forwarding on the local host, it sends ARP replies mapping all IPs to the local MAC address. Also, it can flood the local network with random MAC addresses (like macof), causing switches to send packets to all ports.
Astaro Portscan Detection is a netfilter target which will attempt to detect TCP and UDP port scans and log them to syslog. This target is based upon Solar Designer's scanlogd. It suppports mutliple levels of logging, custom prefixes for entries, weighted total port scan detection, and port scan temporal spread detection.
audio-entropyd feeds the /dev/random device with entropy data read from an audio device. The audio data is not copied as is, but first 'de-biased' and analyzed to determine how many bits of entropy are in it. This program is useful for systems doing many cryptographic tasks like VPN endpoints or GPG clients; it helps prevent the /dev/random device from being depleted and blocking reads.
Authforce is an HTTP authentication brute forcer. Using various methods, it attempts brute force username and password pairs for a site. It has the ability to try common usernames and passwords, username derivations, and common username/password pairs. It is used both to test the security of your site and to highlight the insecurity of HTTP authentication due to the fact that users just don't pick good passwords.
Automated Password Generator is a set of tools for random password generation including a standalone password generator, an RFC972 password generation server, and a Perl client for the password generation server. These feature a built-in X9.17 random number generator, and 35 modes of password generation, including pronounceable password generation.
BeeCrypt is an ongoing project to provide strong and fast cryptography in the form of a toolkit usable by commercial and open source projects. Included in the library are entropy sources, random generators, block ciphers, hash functions, message authentication codes, multiprecision integer routines, and public key primitives.