cryptopals

Solving cryptopals challenges (in Python) ! Limiting myself to only use modules from the standard library.

Environment

(.venv) cryptopals$ python --version
Python 3.11.2

To validate challenges

(.venv) cryptopals$ pytest */*.py

Use -vv and -s for more output.

To run a particular challenge

(.venv) cryptopals$ python set1/challenge1.py

Progress

Progress: 45/66 (68.18 %) completed (last completed, Challenge 45)

Set 1

• Challenge 1 Convert hex to base64
• Challenge 2 Fixed XOR
• Challenge 3 Single-byte XOR cipher
• Challenge 4 Detect single-character XOR
• Challenge 5 Implement repeating-key XOR
• Challenge 6 Break repeating-key XOR
• Challenge 7 AES in ECB mode
• Challenge 8 Detect AES in ECB mode

Set 2

• Challenge 9 Implement PKCS#7 padding
• Challenge 10 Implement CBC mode
• Challenge 11 An ECB/CBC detection oracle
• Challenge 12 Byte-at-a-time ECB decryption (Simple)
• Challenge 13 ECB cut-and-paste
• Challenge 14 Byte-at-a-time ECB decryption (Harder)
• Challenge 15 PKCS#7 padding validation
• Challenge 16 CBC bitflipping attacks

Set 3

• Challenge 17 The CBC padding oracle
• Challenge 18 Implement CTR, the stream cipher mode
• Challenge 19 Break fixed-nonce CTR mode using substitutions
• Challenge 20 Break fixed-nonce CTR statistically
• Challenge 21 Implement the MT19937 Mersenne Twister RNG
• Challenge 22 Crack an MT19937 seed
• Challenge 23 Clone an MT19937 RNG from its output
• Challenge 24 Create the MT19937 stream cipher and break it

Set 4

• Challenge 25 Break "random access read/write" AES CTR
• Challenge 26 CTR bitflipping
• Challenge 27 Recover the key from CBC with IV=Key
• Challenge 28 Implement a SHA-1 keyed MAC
• Challenge 29 Break a SHA-1 keyed MAC using length extension
• Challenge 30 Break an MD4 keyed MAC using length extension
• Challenge 31 Implement and break HMAC-SHA1 with an artificial timing leak
• Challenge 32 Break HMAC-SHA1 with a slightly less artificial timing leak

Set 5

• Challenge 33 Implement Diffie-Hellman
• Challenge 34 Implement a MITM key-fixing attack on Diffie-Hellman with parameter injection
• Challenge 35 Implement DH with negotiated groups, and break with malicious "g" parameters
• Challenge 36 Implement Secure Remote Password (SRP)
• Challenge 37 Break SRP with a zero key
• Challenge 38 Offline dictionary attack on simplified SRP
• Challenge 39 Implement RSA
• Challenge 40 Implement an E=3 RSA Broadcast attack

Set 6

• Challenge 41 Implement unpadded message recovery oracle
• Challenge 42 Bleichenbacher's e=3 RSA Attack
• Challenge 43 DSA key recovery from nonce
• Challenge 44 DSA nonce recovery from repeated nonce
• Challenge 45 DSA parameter tampering
• Challenge 46 RSA parity oracle
• Challenge 47 Bleichenbacher's PKCS 1.5 Padding Oracle (Simple Case)
• Challenge 48 Bleichenbacher's PKCS 1.5 Padding Oracle (Complete Case)

Set 7

• Challenge 49 CBC-MAC Message Forgery
• Challenge 50 Hashing with CBC-MAC
• Challenge 51 Compression Ratio Side-Channel Attacks
• Challenge 52 Iterated Hash Function Multicollisions
• Challenge 53 Kelsey and Schneier's Expandable Messages
• Challenge 54 Kelsey and Kohno's Nostradamus Attack
• Challenge 55 MD4 Collisions
• Challenge 56 RC4 Single-Byte Biases

Set 8

• Challenge 57 Diffie-Hellman Revisited: Small Subgroup Confinement
• Challenge 58 Pollard's Method for Catching Kangaroos
• Challenge 59 Elliptic Curve Diffie-Hellman and Invalid-Curve Attacks
• Challenge 60 Single-Coordinate Ladders and Insecure Twists
• Challenge 61 Duplicate-Signature Key Selection in ECDSA (and RSA)
• Challenge 62 Key-Recovery Attacks on ECDSA with Biased Nonces
• Challenge 63 Key-Recovery Attacks on GCM with Repeated Nonces
• Challenge 64 Key-Recovery Attacks on GCM with a Truncated MAC
• Challenge 65 Truncated-MAC GCM Revisited: Improving the Key-Recovery Attack via Ciphertext Length Extension
• Challenge 66 Exploiting Implementation Errors in Diffie-Hellman