cryptopals

Implementation of the Cryptopals Matasano Crypto Challenges.
Coded in Python 3.

Table of Contents

• Installation
• License
• Usage
• Examples
  • No arguments required, no user interaction required
  • No arguments required, user interaction required
  • With server and client scripts, argument required for client
  • With server, client and MITM scripts, arguments required for all
  • With client vs server/attacker scripts, arguments required for all

Installation

Get the implementation's git repo from git@github.com:rjpdasilva/cryptopals.git.
The repo's directory structure is:

.               # Repo's root ('README.md', 'LICENSE.md').
└─ src          # Challenge scripts.
   ├─ data      # Data files (input data, expected results, etc.).
   └─ utils     # Utility modules.

A Python 3 installation is required for running the samples.

Some scripts (e.g. cp_test_c38_attacker.py) require access to a dictionary "words" file under /usr/share/dict/words. Check with your distro how to install this file/package, if not installed already.

The following core modules are used by the implementation:

• base64
• hashlib
• hmac
• http.server
• re
• socket
• socketserver
• string
• struct
• sys
• threading
• time
• urllib.parse
• urllib.request

Besides the core modules that are part of the Python installation, the following additional modules (and respective package install command) are required:

• Crypto (pip install pycrypto)

License

Refer to the 'LICENSE.md' file.

Usage

Each challenge has a python script for running it, named cp_test_c<nn>.py, where <nn> is the challenge number. All the challenges' scripts are inside the src/ folder.

For example:

• cp_test_c06.py is for Challenge 6.
• cp_test_c21.py is for Challenge 21.

For running a challenge:

• Use a shell placed on the challenge scripts folder (src/).
• Call python with the challenge script:
  python cp_test_c<nn>.py
• Example:
  python cp_test_c12.py

Notes:

• In general, the challenges' scripts require no arguments, but, in some cases, arguments may be required (e.g. cp_test_c31.py), in which case the required arguments will be described when running it without any arguments.
• Some scripts require user input and/or interaction. This will be noticeable when running these scripts.
• Some challenges require a server to be run before executing the actual test script. This is the case of cp_test_c31.py, where the server script is cp_test_c31_server.py. This naming scheme is used for all challenges with a client and server.
• Some challenges (e.g. MITM - Man in The Middle attacks) require a real server and a MITM server to be started before running the challenge's test script. For example, Challenge 34, tested by running the cp_test_c34.py script, needs a real server cp_test_c34_server.py and the MITM server cp_test_c34_mitm.py scripts to be started before testing. This naming scheme is kept the same in all client/server with MITM attack challenges.
• Some challenges (e.g. Challenge 38) have client (cp_test_c38.py), server (cp_test_c38_server.py) and attacker (cp_test_c38_attacker.py) scripts. In these cases, the client shall be run against either the server (a real server) or the attacker (an attacker impersonating the server). In either cases, the script acting as server must be ran first. This naming scheme is kept the same in all client vs server/attacker challenges.
• Challenge specific data is presented to the user.
• The final challenge test result is presented in the end.

Examples

Below are some examples of running the challenges.

No arguments required, no user interaction required

$ python cp_test_c03.py
cp_test_c03.py: ------------------------------------------------------------
cp_test_c03.py: Challenge 03: Single-byte XOR cipher
cp_test_c03.py: ------------------------------------------------------------
cp_test_c03.py: in_str   = [1b37373331363f78151b7f2b783431333d78397828372d363c78373e783a393b3736]
cp_test_c03.py: result   = [(key=88/0x58, msg="Cooking MC's like a pound of bacon")], score = [306.073]
cp_test_c03.py: expected = [(key=88/0x58, msg="Cooking MC's like a pound of bacon")]
cp_test_c03.py: ------------------------------------------------------------
cp_test_c03.py: TEST     = [OK]
cp_test_c03.py: ------------------------------------------------------------

No arguments required, user interaction required (entering number of loops)

$ python cp_test_c11.py
cp_test_c11.py: ------------------------------------------------------------
cp_test_c11.py: Challenge 11: An ECB/CBC detection oracle
cp_test_c11.py: ------------------------------------------------------------
Enter number of loops to execute (1 ~ 10000):
2000
cp_test_c11.py: in_file  = [data/data_c06_out.txt]
cp_test_c11.py: loops    = [ 2000]
cp_test_c11.py:   ECB    = [  982] ( 49.10%)
cp_test_c11.py:   CBC    = [ 1018] ( 50.90%)
cp_test_c11.py:   ok     = [ 2000] (100.00%)
cp_test_c11.py:   ko     = [    0] (  0.00%)
cp_test_c11.py: ------------------------------------------------------------
cp_test_c11.py: TEST     = [OK]
cp_test_c11.py: ------------------------------------------------------------

With server and client scripts, argument required for client

This is required, e.g., for Challenge 31.

Starting the server:

$ python cp_test_c31_server.py
cp_test_c31_server.py: ------------------------------------------------------------
cp_test_c31_server.py: Challenge 31: Implement and break HMAC-SHA1 with an artificial timing leak: Server
cp_test_c31_server.py: ------------------------------------------------------------
cp_test_c31_server.py: server_addr   = [localhost]
cp_test_c31_server.py: server_port   = [9000]
cp_test_c31_server.py: server_delay  = [50 ms]
cp_test_c31_server.py: ------------------------------------------------------------
cp_test_c31_server.py: Running server...
cp_test_c31_server.py: (Ctrl+C to abort)
cp_test_c31_server.py: ------------------------------------------------------------

Running the client, which needs one argument specifying the file name:

$ python cp_test_c31.py
cp_test_c31.py: Error: Missing <file_name> arg
cp_test_c31.py: usage: cp_test_c31.py <file_name>

$ python cp_test_c31.py somefile.txt
cp_test_c31.py: ------------------------------------------------------------
cp_test_c31.py: Challenge 31: Implement and break HMAC-SHA1 with an artificial timing leak
cp_test_c31.py: ------------------------------------------------------------
cp_test_c31.py: file_name     = [somefile.txt]
cp_test_c31.py: server_addr   = [localhost]
cp_test_c31.py: server_port   = [9000]
cp_test_c31.py: server_delay  = [50 ms]
cp_test_c31.py: ------------------------------------------------------------
cp_test_c31.py: Breaking...
cp_test_c31.py: ------------------------------------------------------------
Guessing byte 00 (dmin=  50.0)...done: v=d7, d=  52.3
(sig-KO) d7
Guessing byte 01 (dmin= 100.0)...done: v=1c, d= 103.0
(sig-KO) d71c
Guessing byte 02 (dmin= 150.0)...

With server, client and MITM scripts, arguments required for all

This is used, e.g., in Challenge 34.

Starting the server (1st incorrectly without arguments, then correctly):

$ python cp_test_c34_server.py
cp_test_c34_server.py: Error: Missing arguments
cp_test_c34_server.py: usage: cp_test_c34_server.py <server_addr> <server_port>


$ python cp_test_c34_server.py localhost 9001
cp_test_c34_server.py: ------------------------------------------------------------
cp_test_c34_server.py: Challenge 34: Implement a MITM key-fixing attack on Diffie-Hellman with parameter injection: Server
cp_test_c34_server.py: ------------------------------------------------------------
cp_test_c34_server.py: server_addr = [localhost]
cp_test_c34_server.py: server_port = [9001]
cp_test_c34_server.py: ------------------------------------------------------------
cp_test_c34_server.py: Running server...
cp_test_c34_server.py: (Ctrl+C to abort)
cp_test_c34_server.py: ------------------------------------------------------------

Starting the MITM attacker (1st incorrectly without arguments, then correctly):

$ python cp_test_c34_mitm.py
cp_test_c34_mitm.py: Error: Missing arguments
cp_test_c34_mitm.py: usage: cp_test_c34_mitm.py <mitm_addr> <mitm_port> <server_addr> <server_port>

$ python cp_test_c34_mitm.py localhost 9000 localhost 9001
cp_test_c34_mitm.py: ------------------------------------------------------------
cp_test_c34_mitm.py: Challenge 34: Implement a MITM key-fixing attack on Diffie-Hellman with parameter injection: MITM
cp_test_c34_mitm.py: ------------------------------------------------------------
cp_test_c34_mitm.py: mitm_addr   = [localhost]
cp_test_c34_mitm.py: mitm_port   = [9000]
cp_test_c34_mitm.py: server_addr = [localhost]
cp_test_c34_mitm.py: server_port = [9001]
cp_test_c34_mitm.py: ------------------------------------------------------------
cp_test_c34_mitm.py: Running MITM server...
cp_test_c34_mitm.py: (Ctrl+C to abort)
cp_test_c34_mitm.py: ------------------------------------------------------------

Starting the client to connect with real server on port 9001 (1st incorrectly without arguments, then correctly):

$ python cp_test_c34.py
cp_test_c34.py: Error: Missing arguments
cp_test_c34.py: usage: cp_test_c34.py <server_addr> <server_port> '<msg_to_send>'


$ python cp_test_c34.py localhost 9001 'This is a test message for Challenge 34!!!'
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Challenge 34: Implement a MITM key-fixing attack on Diffie-Hellman with parameter injection: Client
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: server_addr = [localhost]
cp_test_c34.py: server_port = [9001]
cp_test_c34.py: client_msg  = [This is a test message for Challenge 34!!!]
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Executing...
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Executing...done
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: success     = [True]
cp_test_c34.py: server_msg  = [This is a test message for Challenge 34!!!]
cp_test_c34.py: p           = [2410312426921032588552076022197566074856950548502459942654116941958108831682612228890093858261341614673227141477904012196503648957050582631942730706805009223062734745341073406696246014589361659774041027169249453200378729434170325843778659198143763193776859869524088940195577346119843545301547043747207749969763750084308926339295559968882457872412993810129130294592999947926365264059284647209730384947211681434464714438488520940127459844288859336526896320919633919]
cp_test_c34.py: g           = [2]
cp_test_c34.py: a           = [1799556359217574138302394686461232382539154993105913817210303481854944919685295423166624493081553358610444092412252629803030780026174625037454904589483729705897210231049138586839704431440724625989473945002326630265189356990031390277941183992375517248385501921337771870775286607755315969136136806839331474633312083258838858001305005607014439636506041864536395951225478852245452693966195921832350928936294339059363183991026222254867911668235606406506658776020632071]
cp_test_c34.py: A           = [2393756105909493757837726052892113692389492266056739806553434361232403489523676946361077538250681656684888594511409111742249003095783712333520651652309116280969765850279672156979700283674303931078592082289417423711922793607864749228857554745606767934462417916261883732385906882038725811782913490508081748064494923225995756234547098762000670618532854128900118217888460388208311787901170473881827863268333657893266539563928871560636184404300110153644719204338359710]
cp_test_c34.py: B           = [1904542986915325800766610364746505964555381739070232185660269103888338443400495168085467452468145881716375638972541606663639122898394808453159031203431808024404017066689227081702234676962161625800088109601935579029411210531665651622560364792954435356509835535420201879672690928507773545086626105849353765583863057400570202982861344801957588293439151654155335156581587158796191487599139181662981706829625180201144589476360491139688780436773547886883010553687716735]
cp_test_c34.py: s           = [1489565576219369970311610343717827023736216936045668853571411220280382445345219633220664788154863363807372743952470790774393190543655173574257319653511853857088096786554363799780180310839608819984225673711959447266062059941781986224972849680504260699151712157836008468751992023549270654383937117291168701720038258945915985440847850675072006784268271472711855623846115492191130268066668313176231291710966921958979373324733772006452414524322869763456297078231347119]
cp_test_c34.py: k           = [be9ed25142055425d5cdf938cf920530]
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: TEST        = [OK]
cp_test_c34.py: ------------------------------------------------------------

Starting the client to connect with MITM attacker on port 9000 (1st incorrectly without arguments, then correctly):

$ python cp_test_c34.py
cp_test_c34.py: Error: Missing arguments
cp_test_c34.py: usage: cp_test_c34.py <server_addr> <server_port> '<msg_to_send>'


$ python cp_test_c34.py localhost 9000 'This is a test message for Challenge 34!!!'
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Challenge 34: Implement a MITM key-fixing attack on Diffie-Hellman with parameter injection: Client
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: server_addr = [localhost]
cp_test_c34.py: server_port = [9000]
cp_test_c34.py: client_msg  = [This is a test message for Challenge 34!!!]
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Executing...
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: Executing...done
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: success     = [True]
cp_test_c34.py: server_msg  = [This is a test message for Challenge 34!!!]
cp_test_c34.py: p           = [2410312426921032588552076022197566074856950548502459942654116941958108831682612228890093858261341614673227141477904012196503648957050582631942730706805009223062734745341073406696246014589361659774041027169249453200378729434170325843778659198143763193776859869524088940195577346119843545301547043747207749969763750084308926339295559968882457872412993810129130294592999947926365264059284647209730384947211681434464714438488520940127459844288859336526896320919633919]
cp_test_c34.py: g           = [2]
cp_test_c34.py: a           = [2227764430602070007397969750035736901300405612223576229226881829287830942202329689706029754286382441716234829413122587914721616246791064266614124006476970521132428770097170499109628898166017354745176809004433068593701674412008148565319131821337607536223623065963120864621496990882974682385913892417806577603838488748994867888168968320686232579639074735105307979566759746023755908890524892869467670951119262432319656297247372216088071899206049657112695063639961576]
cp_test_c34.py: A           = [735765577145384398771388620910480668507508996980783667147731221843220338699776357822989759440422036457733508428967564278672144346897697616260205088196627709585458027618350769074690117534061817771407308864408168101887419309086220587925651514940847045375599772907353941439584546519727347919368026309336209957846904828368825452966774523660070830891702498369304404843948414743784346536015739362406422636336397731373465098458990332400401885431951455736574748388781482]
cp_test_c34.py: B           = [2410312426921032588552076022197566074856950548502459942654116941958108831682612228890093858261341614673227141477904012196503648957050582631942730706805009223062734745341073406696246014589361659774041027169249453200378729434170325843778659198143763193776859869524088940195577346119843545301547043747207749969763750084308926339295559968882457872412993810129130294592999947926365264059284647209730384947211681434464714438488520940127459844288859336526896320919633919]
cp_test_c34.py: s           = [0]
cp_test_c34.py: k           = [da39a3ee5e6b4b0d3255bfef95601890]
cp_test_c34.py: ------------------------------------------------------------
cp_test_c34.py: TEST        = [OK]
cp_test_c34.py: ------------------------------------------------------------

With client vs server/attacker scripts, arguments required for all

This is used, e.g., in Challenge 38.

Starting the server (1st incorrectly without arguments, then correctly):

$ python cp_test_c38_server.py
cp_test_c38_server.py: Error: Missing arguments
cp_test_c38_server.py: usage: cp_test_c38_server.py <server_addr> <server_port> '<user>' '<password>'

$ python cp_test_c38_server.py localhost 9001 rjpdasilva mypass
cp_test_c38_server.py: ------------------------------------------------------------
cp_test_c38_server.py: Challenge 38: Offline dictionary attack on simplified SRP: Server
cp_test_c38_server.py: ------------------------------------------------------------
cp_test_c38_server.py: server_addr = [localhost]
cp_test_c38_server.py: server_port = [9001]
cp_test_c38_server.py: user        = [rjpdasilva]
cp_test_c38_server.py: password    = [butter]
cp_test_c38_server.py: ------------------------------------------------------------
cp_test_c38_server.py: Running server...
cp_test_c38_server.py: (Ctrl+C to abort)
cp_test_c38_server.py: ------------------------------------------------------------

Starting the attacker (impersonating the server) instead of the server:

$ python cp_test_c38_attacker.py
cp_test_c38_attacker.py: Error: Missing arguments
cp_test_c38_attacker.py: usage: cp_test_c38_attacker.py <server_addr> <server_port>

$ python cp_test_c38_attacker.py localhost 9001
cp_test_c38_attacker.py: ------------------------------------------------------------
cp_test_c38_attacker.py: Challenge 38: Offline dictionary attack on simplified SRP: Attacker
cp_test_c38_attacker.py: ------------------------------------------------------------
cp_test_c38_attacker.py: server_addr = [localhost]
cp_test_c38_attacker.py: server_port = [9001]
cp_test_c38_attacker.py: ------------------------------------------------------------
cp_test_c38_attacker.py: Running server...
cp_test_c38_attacker.py: (Ctrl+C to abort)
cp_test_c38_attacker.py: ------------------------------------------------------------

Starting the client, connecting to either the attacker or the server, depending on which is running:

$ python cp_test_c38.py
cp_test_c38.py: Error: Missing arguments
cp_test_c38.py: usage: cp_test_c38.py <server_addr> <server_port> '<user>' '<password>'

$ python cp_test_c38.py localhost 9001 rjpdasilva butter
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: Challenge 38: Offline dictionary attack on simplified SRP: Client
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: server_addr = [localhost]
cp_test_c38.py: server_port = [9001]
cp_test_c38.py: user        = [rjpdasilva]
cp_test_c38.py: password    = [butter]
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: Executing...
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: Executing...done
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: auth_msg    = [OK]
cp_test_c38.py: success     = [True]
cp_test_c38.py: N           = [2410312426921032588552076022197566074856950548502459942654116941958108831682612228890093858261341614673227141477904012196503648957050582631942730706805009223062734745341073406696246014589361659774041027169249453200378729434170325843778659198143763193776859869524088940195577346119843545301547043747207749969763750084308926339295559968882457872412993810129130294592999947926365264059284647209730384947211681434464714438488520940127459844288859336526896320919633919]
cp_test_c38.py: g           = [2]
cp_test_c38.py: k           = [3]
cp_test_c38.py: a           = [251175953244944880708210168915670758342570697662878390645251180044711610098750402071208408522024962945466086272768243237074614968111742451562108433180045248400535352872936072779377462603320572153008364873659018737564863037036050440585377095661400075457944404618483400660200484205944562370370339879677095565222265096427424602261203345799059957712259526491430038315714385553557005705966044025331951340358308128089629064593485511540061977786398173305320785507510092]
cp_test_c38.py: A           = [572953135103288934909262532328997350189897835205953133116616629578331827232046113237150364243618089464864449756270521037440077689231666667159551021486918047629005034469446011230621480553794096869610124493533144271196953413475421868149045241733256907109942998976918704991934092900373685065309603773809593928822507744709360610129023422564507133850407169034479528914067979564462667631233762689759987592602270405414552476653204204089925687540964613752621294286605489]
cp_test_c38.py: salt        = [0]
cp_test_c38.py: B           = [32]
cp_test_c38.py: u           = [1]
cp_test_c38.py: S           = [1331424059001788875953078456210702522375665590072244064163957786046104289498823395111736770084400151302507949400490082921728459182430756088950112819837955777416219021302465252274387564318681905231386104859561434065230301823368341319298919887423951466449974470785961028988665792891769293966298251990198972367482077899611158924055341850411842888282578177664497124956761582654687552140557838146265772681122926910153532622720188446123606631782268606787344888840327270]
cp_test_c38.py: K           = [89a9c75cc554b5c9fbca006b97bb5bc1b9f663c03786d56df22241964d4a57ed]
cp_test_c38.py: ------------------------------------------------------------
cp_test_c38.py: TEST        = [OK]
cp_test_c38.py: ------------------------------------------------------------