pyrit (1)

pyrit [options] command

Pyrit exploits the computational power of many-core- and GPGPU-platforms to create massive databases, pre-computing part of the WPA/WPA2-PSK authentication phase in a space-time tradeoff. It is a powerful attack against one of the world's most used security-protocols.

This document tries to describe and explain all functions the commandline-client pyrit provides. One or more options may be given on the commandline to customize a command. The exact behaviour of options depends on the command.

At the time of this writing, cowpatty is not available in Debian. References to cowpatty and its commands are nevertheless preserved for the sake of completeness.

Pyrit recognizes the following options:

-b BSSID

Specifies a BSSID. Can be used to restrict commands to certain Access-Points.

-e ESSID

Specifies the ESSID. Commands usually refer to all ESSIDs in the database when this option is omitted.

-i infile

Specifies a filename to read from; the special filename "-" can be used for stdin. The file may be gzip-compressed in which case its name must end in .gz for transparent decompression.

-o outfile

Specifies a filename to write to; the special filename "-" can be used for stdout. Filenames that end in .gz cause pyrit to gzip-compress the file on the fly.

-r capture-file

Specifies a packet-capture file in pcap format (possibly gzip-compressed) or a device (e.g.: "wlan0") to capture from.

-u URL

Specifies the URL of the storage-device in the form of

driver://username:password@host:port/database

Pyrit can use the filesystem, a remote Pyrit-Relay-Server and, if the package python-sqlalchemy is installed, SQL-Databases as storage. The driver file:// refers to Pyrit's own filesystem-based storage, http:// connects to a Pyrit-Relay-Server and all other URLs are passed directly to python-sqlalchemy, if available. The default storage-URL can also be specified by the key defaultstorage in pyrit's configuration file (see FILES below).

--all-handshakes

The commands attack_batch, attack_db, attack_cowpatty and attack_passthrough automatically use the single handshake of highest quality only. In some cases even this handshake may have been wrongfully reconstructed from the captured data, rendering the attack futile. In case more than one EAPOL-handshake is reconstructed from the capture-file, the option --all-handshakes may be used to attack all handshakes reconstructable from the captured data. Exact behaviour of the commands affected by this option is described below.

analyze

Parse one or more packet-capture files (in pcap-format, possibly gzip-compressed) given by the option -r and try to detect Access-Points, Stations and EAPOL-handshakes. For example:

pyrit -r "test*.pcap" analyze

Pyrit shows a list of Access-Points, associated Stations and EAPOL-handshakes that could be identified from the captured data. Handshakes are shown ordered by their "quality":

Good: The handshake includes the challenge from the Access-Point, the response from the Station and the confirmation from the Access-Point.

Workable: The handshake includes the response from the Station and the confirmation from the Access-Point. The challenge was not captured.

Bad: The handshake includes the challenge from the Access-Point and the response from the Station. The confirmation was not captured.

Handshakes of the same quality are ordered by how close the packets that make up the handshake are to each other.

attack_batch

Attack an EAPOL-handshake found in the packet-capture file(s) given by the option -r using the Pairwise Master Keys and passwords stored in the database. The options -b and -e can be used to specify the Access-Point to attack; it is picked automatically if both options are omitted. The password is written to the filename given by the option -o if specified. For example:

pyrit -r test.pcap -e MyNetwork -b 00:de:ad:c0:de:00 \
    -o MyNetworkPassword.txt attack_batch

Pairwise Master Keys that previously have been computed and stored in the database are taken from there; all other passwords are translated into their respective Pairwise Master Keys and added to the database for later re-use. ESSIDs are created automatically in the database if necessary.

Pyrit works down the list of reconstructed EAPOL-handshakes in case the option --all-handshakes is supplied.

attack_cowpatty

Attack an EAPOL-handshake found in the packet-capture file(s) given by the option -r using Pairwise Master Keys from a cowpatty-like file (e.g. generated by ``genpmk'' from cowpatty, or export_cowpatty below) given by the option -f. The options -b and -e can be used to specify the Access-Point to attack; it is picked automatically if both options are omitted. The password is written to the filename given by the option -o if specified. The cowpatty-file may be gzip-compressed and must match the chosen ESSID. For example:

pyrit -r test.pcap -e MyOwnNetwork \
    -i MyOwnNetwork.cow.gz -o - attack_cowpatty

Pyrit's own database is not touched by attack_cowpatty.

Pyrit attacks all EAPOL-handshakes at the same time if the option --all-handshakes is supplied. This will reduce throughput (e.g.: 33% throughout in case of three handshakes).

attack_db

Attack an EAPOL-handshake found in the packet-capture file(s) given by the option -r using the Pairwise Master Keys stored in the database. The options -b and -e can be used to specify the Access-Point to attack; it is picked automatically if both options are omitted. The password is written to the filename given by the option -o if specified. For example:

pyrit -r test.pcap -e MyOtherNetwork attack_db

Only Pairwise Master Keys that have been computed previously and are stored in the database are used by attack_db.

Pyrit works down the list of reconstructed EAPOL-handshakes in case the option --all-handshakes is supplied.

attack_passthrough

Attack an EAPOL-handshake found in the packet-capture file(s) given by the option -r using the passwords read from the file given by the option -i. The options -b and -e can be used to specify the Access-Point to attack; it is picked automatically if both options are omitted. The password is written to the filename given by the option -o if specified. For example:

pyrit -r test.pcap -b 00:de:ad:be:ef:00 \
    -i words.txt attack_passthrough

This command circumvents Pyrit's database and should only be used if storage-space is a problem (e.g. on LiveCDs). You should consider using attack_batch otherwise.

Pyrit attacks all EAPOL-handshakes at the same time if the option --all-handshakes is supplied.

batch

Start to translate all passwords in the database into their respective Pairwise Master Keys and store the results in the database. The option -e may be used to restrict this command to a single ESSID; if it is omitted, all ESSIDs are processed one after the other in undefined order. For example:

pyrit -e NETGEAR batch

The option -o can be used to specify a filename the results should additionally be written to in cowpatty's binary format. The option -e becomes mandatory and the ESSID is automatically created in the database if necessary. Pairwise Master Keys that previously have been computed and stored in the database are exported from there without further processing. Pyrit stops and exits if an IOError is raised while writing to the specified file. This makes it very convenient to pipe results directly to other programs but also keep them for later use. For example:

pyrit -e NETGEAR -o - batch | \
    cowpatty -d - -r wpatestcapture.cap -s NETGEAR

benchmark

Determine the peak-performance of the available hardware by computing dummy-results. For example:

pyrit benchmark

check_db

Unpack the entire database and check for errors like data corruption or reference errors. This function does not check the value of computed results (see verify). For example:

pyrit check_db

create_essid

Add new ESSIDs to the database. A single ESSID may be given by the option -e. Multiple ESSIDs can be created by supplying a file (one per line) via the option -i. Re-creating an existing ESSID does not result in an error. For example:

pyrit -e NETGEAR create_essid

delete_essid

Delete the ESSID given by -e from the database. This includes all results that may have been stored for that particular ESSID. For example:

pyrit -e NETGEAR delete_essid

eval

Count all available passwords, all ESSIDs and their respective results in the database. For example:

pyrit eval

export_passwords

Write all passwords that are currently stored in the database to a new file given by -o. Passwords are terminated by a single newline-character ("\n"). Existing files are overwritten without confirmation. For example:

pyrit -o myword.txt.gz export_passwords

export_cowpatty

Write all results for the ESSID given by -e to the file given by -o in cowpatty's binary format. Existing files are overwritten without confirmation. For example:

pyrit -o NETGEAR.cow -e NETGEAR export_cowpatty

export_hashdb

Write all results currently stored in the database to the airolib-ng-database given by -o. The database is created with a default table layout if the file does not yet exist. The option -e can be used to limit the export to a single ESSID. For example:

pyrit -o NETGEAR.db -e NETGEAR export_hashdb

import_passwords

Read the file given by -i and import one password per line to the database. The passwords may contain all characters (including NULL-bytes) apart from the terminating newline-character ("\n"). Passwords that are not suitable for being used with WPA-/WPA2-PSK are ignored. Pyrit's storage-implementation guarantees that all passwords remain unique throughout the entire database. For example:

pyrit -i dirty_words.txt import_passwords

import_unique_passwords

Read the file given by -i and import one password per line to the database. The passwords may contain all characters (including NULL-bytes) apart from the terminating newline-character ("\n"). Passwords that are not suitable for being used with WPA-/WPA2-PSK are ignored. This command does not check if there are duplicate passwords within the file or between the file and the database; it should be used with caution to prevent the database from getting poisoned with duplicated passwords. This command however can be much faster than import_passwords. For example:

pyrit -i dirty_words.txt import_unique_passwords

list_cores

Show a list of all available hardware modules Pyrit currently uses. For example:

pyrit list_cores

list_essids

Show a list of all ESSIDs currently stored in the database. This function is faster than eval in case you don't need to know the number of computed results. For example:

pyrit list_essids

passthrough

Read passwords from the file given by -i and compute their Pairwise Master Keys for the ESSID given by -e. The results are written to the file specified by -o in cowpatty's binary format and are not stored in the database for later use. This command therefor circumvents the entire database and should only be used if storage-space is a problem (e.g. when using Pyrit on a LiveCD). The batch-command provides exactly the same functionality as passthrough but can give much better performance as results may be read from the database instead of recomputing them. For example:

pyrit -i dirty_words.txt.gz -e NETGEAR \
    -o - passthrough | cowpatty -d - \
    -r wpatestcapture.cap -s NETGEAR

relay

Start a server to relay another storage device via XML-RPC; other Pyrit-clients can use the server as storage-device. This allows one to have network-based access to storage source that don't provide network-access on their own (like file:// and sqlite://) or hide a SQL-database behind a firewall and let multiple clients access that database only via Pyrit's RPC-interface. The TCP-port 17934 must be open for this function to work. For example, on the server (where the database is):

pyrit -u sqlite://var/local/pyrit.db relay

and the client (where the big GPU is):

pyrit -u http://192.168.0.100:17934 batch

selftest

Run an extensive selftest for about 60 seconds. This test includes the entire scheduling-mechanism and all cores that are listed by list_cores. You can use this function to detect broken hardware-modules or malicious network-clients. For example:

pyrit selftest

serve

Start a server that provides access to the local computing hardware to help other Pyrit clients. The server's IP-address should be added to the client's configuration file (see FILES) as a space-separated list under known_clients. The client's rpc_server-setting must also be set to 'true'. The TCP- and UDP-Port 17935 must be accessible. For example, on the server (where the GPU is):

pyrit serve

and on the client (the server's IP-address has been added to known_clients and rpc_server is set to 'true'):

pyrit -r test.pcap -b 00:de:ad:be:ef:00 \
    -i words.txt attack_passthrough

strip

Parse one or more packet-capture files given by the option -r, extract only packets that are necessary for EAPOL-handshake detection and write a new dump to the filename given by the option -o. The options -e and -b can be used to filter certain Access-Points. For example:

pyrit -r "large_dumps_*.pcap" -e MyNetwork \
    -o tiny_compressed_dump_MyNetwork.dump.gz strip

stripLive

Parse a packet-capture file given by the option -r, extract only packets that are necessary for EAPOL-handshake detection and write a new dump to the file given by the option -o. This command differs from strip as the capture-file can be any character device including sockets and other pseudo-files that look like files in pcap-format. stripLive writes relevant packets to the new file given by -o as they arrive instead of trying to read the entire capture-file first.

pyrit -r /temp/kismet_dump -o small_dump.pcap stripLive

verify

Randomly pick 10% of the results stored in the database and verify their value by recomputation. You need this function if you suspect broken hardware or malicious network-clients. For example:

pyrit -e NETGEAR verify

If command succeeds, pyrit's process exit status is set to 0; otherwise it is set to 1 and (usually) an error message or a python-traceback is written to stderr. The following commands also indicate an error condition in certain cases:

    analyze: Not at least one valid EAPOL-handshake could be detected.

    attack_passthrough, attack_batch, attack_db and attack_cowpatty: The password could not be found.

    verify At least one workunit contained invalid results.

    check_db Errors in the database were found (and possibly fixed).

~/.pyrit/config

The pyrit configuration file. You can find a documented example in /usr/share/doc/pyrit/examples/config.example.

The author does not encourage or support using pyrit for the infringement of people's communication-privacy. The exploration and realization of the technology discussed here motivate as a purpose of their own; this is documented by the open development, strictly sourcecode-based distribution and 'copyleft'-licensing.

pyrit was written by Lukas Lueg <[email protected]>.

This manual page was written by Christian Kastner <[email protected]> for the Debian project (but may be used by others).