ahefutil

Implementation of the "Algebra Homomorphic Encryption Scheme Based on Fermat's Little Theorem" (AHEF)

TODOS

• Umbrella CLI
• Support Radix-64 encoding (currently only HEX)
• Make choice of encoding an OPTION
• Replace json with json-ld (eat your own dogfood)
• Fix precision issues
• Implement grcy_mpi_rational using signed big integers (e.g. https://mattmccutchen.net/bigint/)

Usage

Generate two (very) large random primes as private keys (keep them secret):

./genpkey -o private_keys.json -k 1024

Extract public key from private keys:

./extract -p private_keys.json -o public_key.json

Use private keys to encrypt some values A=2.5 and B=1.3:

./encrypt -p private_keys.json -o A.enc -v 2.5
./encrypt -p private_keys.json -o B.enc -v 1.3

Use the public key to add two encrypted numbers together:

./addenc -p public_key.json -a A.enc -b B.enc -o C.enc

Use the public key to subtract an encrypted number from another encrypted number:

./subenc -p public_key.json -a A.enc -b B.enc -o D.enc

Use the public key to multiply two encrypted numbers:

./mulenc -p public_key.json -a A.enc -b B.enc -o E.enc

Use the private keys to decrypt the computation results:

./decrypt -p private_keys.json -c C.enc
./decrypt -p private_keys.json -c D.enc
./decrypt -p private_keys.json -c E.enc

Dependencies:

brew install libgcrypt brew tap nlohmann/json brew install nlohmann_json