1.6 KiB
Diffie-Hellman
Diffie-Hellman key exchange.
Alice and Bob use Diffie-Hellman key exchange to share secrets. They start with prime numbers, pick private keys, generate and share public keys, and then generate a shared secret key.
Step 0
The test program supplies prime numbers p and g.
Step 1
Alice picks a private key, a, greater than 1 and less than p. Bob does the same to pick a private key b.
Step 2
Alice calculates a public key A.
A = g**a mod p
Using the same p and g, Bob similarly calculates a public key B from his private key b.
Step 3
Alice and Bob exchange public keys. Alice calculates secret key s.
s = B**a mod p
Bob calculates
s = A**b mod p
The calculations produce the same result! Alice and Bob now share secret s.
Setup
Go through the setup instructions for Kotlin to install the necessary dependencies:
https://exercism.io/tracks/kotlin/installation
Making the test suite pass
Execute the tests with:
$ gradlew test
Use
gradlew.batif you're on Windows
In the test suites all tests but the first have been skipped.
Once you get a test passing, you can enable the next one by removing the
@Ignore annotation.
Source
Wikipedia, 1024 bit key from www.cryptopp.com/wiki. http://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.