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Learn Cryptography in Go
▾
First Secrets
0/4
Strings Are Bytes
10 XP
Bytes and Back
10 XP
Letter Math
15 XP
The Reverse Cipher
15 XP
▾
The Caesar Cipher
0/5
Shifting One Letter
15 XP
Encrypting a Message
15 XP
Leave the Rest Alone
20 XP
Decrypting
20 XP
Uppercase Too
20 XP
▾
Breaking Caesar
0/3
All 26 Doors
20 XP
Counting Letters
20 XP
The Crib Attack
25 XP
▾
The Vigenère Cipher
0/4
A Key That Marches
20 XP
Vigenère Encryption
25 XP
Vigenère Decryption
25 XP
Why Key Length Matters
20 XP
▾
XOR
0/4
The XOR Operator
20 XP
Single-Byte XOR
20 XP
Repeating-Key XOR
25 XP
The One-Time Pad
25 XP
▾
Armoring Ciphertext
0/3
Hex Armor
20 XP
Removing the Armor
20 XP
Base64 Armor
25 XP
▾
Randomness & Keys
0/3
Where Keys Come From
20 XP
Counting Guesses
20 XP
Spotting Weak Keys
20 XP
▾
Hashing
0/3
Fingerprints
25 XP
Tamper Detection
25 XP
Broken Hashes
25 XP
▾
Message Authentication
0/3
Proving Who Sent It
25 XP
HMAC
25 XP
Verifying Safely
25 XP
▾
Brute Force
0/3
The Attacker's Budget
20 XP
Cracking Single-Byte XOR
25 XP
The Dictionary Attack
25 XP
▾
AES
0/3
AES: The Vault
25 XP
Sealing One Block
25 XP
Opening One Block
25 XP
▾
ECB and Its Leak
0/3
Splitting into Blocks
25 XP
The Obvious Mode: ECB
25 XP
Why ECB Leaks
30 XP
▾
Cipher Block Chaining
0/3
Mixing Two Blocks
25 XP
Chaining: CBC
30 XP
The Standard Library's Modes
30 XP
▾
Counter Mode
0/3
CTR: Blocks into Streams
30 XP
Opening a Stream
25 XP
Never Reuse the Counter
30 XP
▾
Padding
0/3
PKCS#7 Padding
25 XP
Unpadding, Suspiciously
30 XP
Sealing Real Text
30 XP
▾
Key Stretching
0/3
Stretching a Password
25 XP
Salt
25 XP
The Attack, Slowed
30 XP
▾
Big Numbers
0/3
Numbers Beyond int64
25 XP
Big Arithmetic
25 XP
Clock Arithmetic Powers
30 XP
▾
Key Exchange
0/3
The Key Exchange Problem
30 XP
Meeting in the Middle
30 XP
Why Size Is Everything
30 XP
▾
RSA
0/4
Building Toy Keys
30 XP
Encrypting with the Public Key
30 XP
Decrypting with the Private Key
30 XP
Digital Signatures
30 XP
▾
Capstone: The Field Messenger
0/4
Capstone: Deriving the Key
30 XP
Capstone: Sealing the Envelope
30 XP
Capstone: The Wax Seal
30 XP
Capstone: Opening the Envelope
30 XP
▾
Relics: The Feistel Engine
0/4
One Turn of the Engine
20 XP
Many Turns
25 XP
Running It Backwards
25 XP
Why the Relic Fell
30 XP
▾
Whispering Streams
0/3
The Whispering Spring
20 XP
The Reused Whisper
30 XP
CTR Was a Stream All Along
25 XP
▾
Seals of Office
0/4
Hash, Then Sign
25 XP
Breaking the Seal
25 XP
The Sealed Envelope
30 XP
The Forger's Trick
30 XP
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