Implement SRA Encrypt/Decrypt

SRA Is implemented in web assembly with rust as a library that operates as a JavaScript worker thread in the browser. It will be used to generate phi and n. These two values will be shared publicly. The user takes phi and n and provides it to generate key pairs in their browser. These key pairs are shared with the contract privately. The javascript will need to generate 52 key pairs for each client in the second phase of securing the shuffled deck.

I used exp_by_squaring to achieve the same as a ** b while only requiring a max u64 register to store the squaring operation. Encrypt and decrypt are inline functions which can be relied upon by transitions in main.leo.

https://en.wikipedia.org/wiki/Mental_poker
https://asecuritysite.com/encryption/comm2
https://xianmu.github.io/posts/2018-09-19-commutative-encryption.html
https://www.dcode.fr/primality-test WASM Library test output for my own sanity:

npm run test:wasm
[INFO]: 🎯  Checking for the Wasm target...
    Finished dev [unoptimized + debuginfo] target(s) in 0.25s
[INFO]: ⬇️  Installing wasm-bindgen...
    Finished test [unoptimized + debuginfo] target(s) in 0.24s
     Running unittests src/lib.rs (target/wasm32-unknown-unknown/debug/deps/zk_poker_worker-3ee4807ad0864e89.wasm)

> zkpoker@0.0.0 test:wasm
> cd ./src/workers/zkPokerWorker && wasm-pack test --node

Set timeout to 20 seconds...
Executing bindgen...                              

running 5 tests

===================
d1 = 29, d2 = 31
e1 = 5, e2 = 7
n = 91
Message = 5
===================
Cipher result (after Alice encrypt): 31
Cipher result (after Bob encrypt): 73
===================
Cipher result (After Bob decrypt): 31
Cipher result (After Alice decrypt): 5
A -> B -> B -> A: 5
Cipher result (After Alice decrypt): 47
Cipher result (After Bob decrypt): 5
A -> B -> A -> B: 5
test zk_poker_worker::tests::test_sra_mock ... ok

===================
phi = 2801307600 n = 2801413507
===================
e1 = 1170454781 d1 = 2423676821
e2 = 1380396943 d2 = 2734228207
n = 2801413507
Message = 63
===================
  Cipher result (after Alice encrypt): 421829602
  Cipher result (after Bob encrypt): 2342371725
  Cipher result (After Bob decrypt): 421829602
  Cipher result (After Alice decrypt): 63
A -> B -> B -> A: 63
  Cipher result (After Alice decrypt): 646018564
  Cipher result (After Bob decrypt): 63
A -> B -> A -> B: 63
test zk_poker_worker::tests::test_sra ... ok

===================
phi = 2760037900 n = 2760144901
e = 1499310121 d = 2684041781
phi bits = 32
n bits = 32
e bits = 31
d bits = 32
===================
test zk_poker_worker::tests::test_generate_key_pair ... ok

===================
phi = 2606871816 n = 2606976467
phi bits = 32
n bits = 32
===================
phi = 3529329076 n = 3529447897
phi bits = 32
n bits = 32
===================
phi = 3236288640 n = 3236403227
phi bits = 32
n bits = 32
===================
phi = 3092657904 n = 3092770001
phi bits = 32
n bits = 32
===================
phi = 2616500416 n = 2616602959
phi bits = 32
n bits = 32
===================
phi = 2367137280 n = 2367234599
phi bits = 32
n bits = 32
===================
phi = 2378030424 n = 2378131739
phi bits = 32
n bits = 32
===================
phi = 2253726904 n = 2253825559
phi bits = 32
n bits = 32
===================
test zk_poker_worker::tests::test_generate_phi_n ... ok

===================
prime = 36433
bits = 16
===================
prime = 42899
bits = 16
===================
prime = 47137
bits = 16
===================
prime = 42589
bits = 16
===================
prime = 61861
bits = 16
===================
prime = 57427
bits = 16
===================
prime = 61627
bits = 16
===================
test zk_poker_worker::tests::test_get_fixed_prime ... ok

test result: ok. 5 passed; 0 failed; 0 ignored

zkCohort / zk_texas_holdem

Implement SRA Encrypt/Decrypt #3