Secure multiparty computation in Julia
Implements Shamir's secret sharing scheme to distribute a number, and the BGW88 protocol for calculating + and * over the resulting numeric representation.
Example from Wikipedia
using SecureComputation
F = GF{Int,1613} #Galois field (finite field, integers mod 1613, perform compute in native Int)
secret = F(1234)
x = shamir(6, secret, F[166, 94]) # == DistributedShares(1:6, F[1494, 329, 965, 176, 1188, 775])
unshamir(x) # == secret
#With 2 random coefficients, you only need 2+1 = 3 pieces to reconstruct the secret
unshamir(x[1:3]) # == secretA more realistic example using the Intel hardware CSPRNG
F = GF{BigInt,1000000004191}
secret = F(1234567890)
x = shamir(RdRand(), 100, 39, secret)
unshamir(x) # == secret
#If I have just 39 pieces, I can also reconstruct the number
unshamir(x[1:39]) # == secret
An example showing a simple matrix computation
using LinearAlgebra, SecureComputation
F = GF{BigInt,1000000004191}
M = rand(RdRand(), F, 3, 3)
MM = shamir.(100, M)
Z=lu(MM)
istril(unshamir.(Z.L)) #true