1 unstable release
| 0.1.0 | Nov 7, 2023 |
|---|
#1773 in Cryptography
5MB
242 lines
rc4ok
Lightweight High-Performance Cryptographically Strong Random Number Generator based on Improved RC4
Overview
RC4OK is a light-weight, high-performance, cryptographically secure random number generator, which is based on an improved version of the RC4 stream cipher, which was proposed in https://ia.cr/2023/1486. It's suitable for use in IOT devices, which might lack presence of an operating system managed pseudo random number generator.
RC4OK pseudo-random number generator can be initialized with a non-empty seed string and it should produce arbitrary long pseudo-random bytes. True random events such as external peripheral interrupts can be used as entropy source and they can be added to the RC4OK PRNG state, though not yet in a thread-safe manner, in this implementation.
Prerequisites
Rust stable toolchain; see https://rustup.rs for installation guide.
# When developing this library, I was using
$ rustc --version
rustc 1.73.0 (cc66ad468 2023-10-03)
I advise you to also use cargo-criterion for running benchmark executable. Read more about it @ https://crates.io/crates/cargo-criterion. You can just issue following command for installing it system-wide.
cargo install cargo-criterion
Testing
For ensuring functional correctness and conformance of this RC4OK PRNG implementation, I generate Known Answer Tests using the official implementation by the RC4OK authors, living @ https://github.com/emercoin/rc4ok.
Note Those (reproducible) steps for generating KAT files are described in the gist https://gist.github.com/itzmeanjan/5d1379b4d324e888a2683d2820b57e23.
Issue following command to run all test cases.
cargo test --lib
Benchmarking
Issue following command for benchmarking RC4OK PRNG, with variable length input and output.
Warning When benchmarking make sure you've disabled CPU frequency scaling, otherwise numbers you see can be pretty misleading. I found https://github.com/google/benchmark/blob/b40db869/docs/reducing_variance.md helpful.
# In case you didn't install `cargo-criterion`, you've to run benchmark with
# RUSTFLAGS="-C opt-level=3 -C target-cpu=native" cargo bench rc4ok
RUSTFLAGS="-C opt-level=3 -C target-cpu=native" cargo criterion rc4ok
On 12th Gen Intel(R) Core(TM) i7-1260P
rc4ok/8B key/32B out (cached)
time: [2574.0575 cycles 2583.6185 cycles 2593.2527 cycles]
thrpt: [64.8313 cpb 64.5905 cpb 64.3514 cpb]
rc4ok/8B key/32B out (random)
time: [2606.7636 cycles 2617.6775 cycles 2628.2137 cycles]
thrpt: [65.7053 cpb 65.4419 cpb 65.1691 cpb]
rc4ok/8B key/128B out (cached)
time: [2997.8248 cycles 3004.5399 cycles 3012.1415 cycles]
thrpt: [22.1481 cpb 22.0922 cpb 22.0428 cpb]
rc4ok/8B key/128B out (random)
time: [3043.8787 cycles 3055.6564 cycles 3066.6192 cycles]
thrpt: [22.5487 cpb 22.4681 cpb 22.3815 cpb]
rc4ok/8B key/512B out (cached)
time: [4658.6544 cycles 4674.6998 cycles 4694.8666 cycles]
thrpt: [9.0286 cpb 8.9898 cpb 8.9590 cpb]
rc4ok/8B key/512B out (random)
time: [4694.0311 cycles 4703.3597 cycles 4713.2270 cycles]
thrpt: [9.0639 cpb 9.0449 cpb 9.0270 cpb]
rc4ok/8B key/2048B out (cached)
time: [11207.3971 cycles 11216.4134 cycles 11224.6109 cycles]
thrpt: [5.4594 cpb 5.4555 cpb 5.4511 cpb]
rc4ok/8B key/2048B out (random)
time: [11259.0064 cycles 11270.4428 cycles 11281.7112 cycles]
thrpt: [5.4872 cpb 5.4817 cpb 5.4762 cpb]
rc4ok/8B key/8192B out (cached)
time: [37420.0994 cycles 37435.8935 cycles 37451.9318 cycles]
thrpt: [4.5673 cpb 4.5654 cpb 4.5634 cpb]
rc4ok/8B key/8192B out (random)
time: [37585.0076 cycles 37608.9629 cycles 37637.5633 cycles]
thrpt: [4.5899 cpb 4.5865 cpb 4.5835 cpb]
rc4ok/32B key/32B out (cached)
time: [2572.5247 cycles 2578.7168 cycles 2584.8764 cycles]
thrpt: [40.3887 cpb 40.2924 cpb 40.1957 cpb]
rc4ok/32B key/32B out (random)
time: [2615.5792 cycles 2625.2851 cycles 2635.2579 cycles]
thrpt: [41.1759 cpb 41.0201 cpb 40.8684 cpb]
rc4ok/32B key/128B out (cached)
time: [2989.8377 cycles 2997.4252 cycles 3004.3600 cycles]
thrpt: [18.7773 cpb 18.7339 cpb 18.6865 cpb]
rc4ok/32B key/128B out (random)
time: [3036.4210 cycles 3044.4885 cycles 3052.7608 cycles]
thrpt: [19.0798 cpb 19.0281 cpb 18.9776 cpb]
rc4ok/32B key/512B out (cached)
time: [4652.0364 cycles 4660.6068 cycles 4668.8399 cycles]
thrpt: [8.5824 cpb 8.5673 cpb 8.5515 cpb]
rc4ok/32B key/512B out (random)
time: [4678.9572 cycles 4692.8719 cycles 4705.5602 cycles]
thrpt: [8.6499 cpb 8.6266 cpb 8.6010 cpb]
rc4ok/32B key/2048B out (cached)
time: [11214.7297 cycles 11225.2264 cycles 11234.2678 cycles]
thrpt: [5.4011 cpb 5.3967 cpb 5.3917 cpb]
rc4ok/32B key/2048B out (random)
time: [11266.6827 cycles 11279.7609 cycles 11293.4054 cycles]
thrpt: [5.4295 cpb 5.4230 cpb 5.4167 cpb]
rc4ok/32B key/8192B out (cached)
time: [37444.1838 cycles 37474.6635 cycles 37511.3311 cycles]
thrpt: [4.5612 cpb 4.5567 cpb 4.5530 cpb]
rc4ok/32B key/8192B out (random)
time: [37568.3293 cycles 37599.5151 cycles 37636.0638 cycles]
thrpt: [4.5764 cpb 4.5719 cpb 4.5681 cpb]
rc4ok/128B key/32B out (cached)
time: [2571.3882 cycles 2579.3929 cycles 2587.1145 cycles]
thrpt: [16.1695 cpb 16.1212 cpb 16.0712 cpb]
rc4ok/128B key/32B out (random)
time: [2623.1407 cycles 2631.9951 cycles 2641.2559 cycles]
thrpt: [16.5078 cpb 16.4500 cpb 16.3946 cpb]
rc4ok/128B key/128B out (cached)
time: [3004.6187 cycles 3012.6715 cycles 3020.3793 cycles]
thrpt: [11.7984 cpb 11.7682 cpb 11.7368 cpb]
rc4ok/128B key/128B out (random)
time: [3049.2580 cycles 3062.2966 cycles 3074.7457 cycles]
thrpt: [12.0107 cpb 11.9621 cpb 11.9112 cpb]
rc4ok/128B key/512B out (cached)
time: [4651.8726 cycles 4659.8927 cycles 4668.0468 cycles]
thrpt: [7.2938 cpb 7.2811 cpb 7.2686 cpb]
rc4ok/128B key/512B out (random)
time: [4710.3644 cycles 4718.4407 cycles 4726.6339 cycles]
thrpt: [7.3854 cpb 7.3726 cpb 7.3599 cpb]
rc4ok/128B key/2048B out (cached)
time: [11224.8340 cycles 11233.1534 cycles 11241.3467 cycles]
thrpt: [5.1661 cpb 5.1623 cpb 5.1585 cpb]
rc4ok/128B key/2048B out (random)
time: [11273.2337 cycles 11284.8074 cycles 11296.7530 cycles]
thrpt: [5.1915 cpb 5.1860 cpb 5.1807 cpb]
rc4ok/128B key/8192B out (cached)
time: [37452.5475 cycles 37471.4525 cycles 37493.1134 cycles]
thrpt: [4.5064 cpb 4.5038 cpb 4.5015 cpb]
rc4ok/128B key/8192B out (random)
time: [37517.3849 cycles 37533.3325 cycles 37551.2108 cycles]
thrpt: [4.5134 cpb 4.5112 cpb 4.5093 cpb]
rc4ok/512B key/32B out (cached)
time: [3787.2402 cycles 3800.8097 cycles 3812.1764 cycles]
thrpt: [7.0077 cpb 6.9868 cpb 6.9618 cpb]
rc4ok/512B key/32B out (random)
time: [3856.9078 cycles 3864.3158 cycles 3871.6352 cycles]
thrpt: [7.1170 cpb 7.1035 cpb 7.0899 cpb]
rc4ok/512B key/128B out (cached)
time: [4234.2484 cycles 4241.7623 cycles 4249.1637 cycles]
thrpt: [6.6393 cpb 6.6278 cpb 6.6160 cpb]
rc4ok/512B key/128B out (random)
time: [4280.2904 cycles 4289.0777 cycles 4297.3391 cycles]
thrpt: [6.7146 cpb 6.7017 cpb 6.6880 cpb]
rc4ok/512B key/512B out (cached)
time: [5872.9725 cycles 5882.1885 cycles 5892.3259 cycles]
thrpt: [5.7542 cpb 5.7443 cpb 5.7353 cpb]
rc4ok/512B key/512B out (random)
time: [5928.2071 cycles 5941.1224 cycles 5953.0667 cycles]
thrpt: [5.8135 cpb 5.8019 cpb 5.7893 cpb]
rc4ok/512B key/2048B out (cached)
time: [12446.3101 cycles 12466.3025 cycles 12484.1382 cycles]
thrpt: [4.8766 cpb 4.8696 cpb 4.8618 cpb]
rc4ok/512B key/2048B out (random)
time: [12533.1298 cycles 12549.1192 cycles 12565.9494 cycles]
thrpt: [4.9086 cpb 4.9020 cpb 4.8958 cpb]
rc4ok/512B key/8192B out (cached)
time: [38646.2054 cycles 38674.0255 cycles 38702.6669 cycles]
thrpt: [4.4465 cpb 4.4432 cpb 4.4401 cpb]
rc4ok/512B key/8192B out (random)
time: [38780.2013 cycles 38808.2085 cycles 38839.4959 cycles]
thrpt: [4.4623 cpb 4.4587 cpb 4.4554 cpb]
Usage
Using RC4OK PRNG is fairly easy.
- Add
rc4okto the [dependencies] section of the Cargo.toml file of your project.
[dependencies]
rc4ok = { git = "https://github.com/itzmeanjan/rc4ok" }
# or
rc4ok = "0.1.0"
- Initialize RC4OK pseudo-random number generator with a non-empty key i.e. seed.
use rc4ok;
fn main() {
const SEED_LEN: usize = 16;
const OUT_LEN: usize = 32;
let seed = vec![0xffu8; SEED_LEN];
let mut out = vec![0u8; OUT_LEN];
// Seed PRNG
let mut rc4ok_prng = rc4ok::RC4ok::init(&seed);
// ...
}
- Request arbitrary many pseudo-random bytes from PRNG object.
// Generate pseudo-random bytes
rc4ok_prng.generate(&mut out);
- You can add some entropy into the RC4OK PRNG state from time to time.
Warning RC4OK state is not yet thread-safe so you can't spawn a thread to harvest entropy and add that to the state of RC4OK PRNG from time to time.
let mut entropy = 0u16; // harvest 16 -bit entropy
rc4ok_prng.add_entropy(entropy); // Add entropy
- Finally you can reset the state of an existing RC4OK PRNG and reinit it with a new non-empty seed.
let another_seed = vec![0x0fu8; SEED_LEN + 1]; // Populate another seed
rc4ok_prng.reset(&another_seed); // Re-seed PRNG
I'm maintaining a program (see src/main.rs) which can be invoked as a binary and requested for producing arbitrary many psuedo-random bytes given a non-empty seed string.
Note
rc4okbinary executable writes requested-many or arbitrary-many pseudo-random bytes directly onto STDOUT device, hence you may want to pipe ( read more @ https://en.wikipedia.org/wiki/Pipeline_(Unix) ) the output to a file or another program.
cargo run --release -- -h # For showing help text
cargo run --release -- -b 256 "this is a seed phrase" # For requesting n (=256) pseudo-random bytes, given a seed string
cargo run --release -- -s "this is a seed phrase" # For requesting arbitrary pseudo-random bytes, given a seed string
# --- --- --- --- ---
# Encode output of rc4ok binary executable as hex string onto STDOUT.
# You may find https://stackoverflow.com/questions/6292645/convert-binary-data-to-hexadecimal-in-a-shell-script helpful.
cargo run --release -- -b 4 "this is a seed phrase" | od -A n -v -t x1 | tr -d ' \n' && echo -e # Outputs 4 pseudo random bytes
cargo run --release -- -s "this is a seed phrase" | od -A n -v -t x1 | tr -d ' \n' && echo -e # Outputs a stream of pseudo random bytes
# Compute SHA256 digest over output of rc4ok binary executable.
cargo run --release -- -b 256 "this is a seed phrase" | sha256sum # = 60ca173a786ab694243e274ee67c758cb562310b743a2708bca3b6fb510e2e54
cargo run --release -- -b 257 "this is a seed phrase" | sha256sum # = 9051dc85e79360c7afda55551c9811fb52bb2fd8cbcabf791d11fd1a43666c8f
cargo run --release -- -b 257 "this is a seed phrase" | head -c 256 | sha256sum # = 60ca173a786ab694243e274ee67c758cb562310b743a2708bca3b6fb510e2e54