eciesrs

Elliptic Curve Integrated Encryption Scheme for secp256k1 in Rust, based on pure Rust implementation of secp256k1.

ECIES functionalities are built upon AES-GCM-256 and HKDF-SHA256.

This is the Rust version of eciespy.

This library can be compiled to the WASM target at your option, see WASM compatibility.

Quick Start

use ecies::{decrypt, encrypt, utils::generate_keypair};

const MSG: &str = "helloworld";
let (sk, pk) = generate_keypair();
let (sk, pk) = (&sk.serialize(), &pk.serialize());

let msg = MSG.as_bytes();
assert_eq!(
    msg,
    decrypt(sk, &encrypt(pk, msg).unwrap()).unwrap().as_slice()
);

Optional pure Rust AES backend

You can choose to use OpenSSL implementation or pure Rust implementation of AES-256-GCM:

ecies = {version = "0.2", default-features = false, features = ["pure"]}

Due to some performance problem, OpenSSL is the default backend.

Pure Rust implementation is sometimes useful, such as building on WASM:

cargo build --no-default-features --features pure --target=wasm32-unknown-unknown

If you select the pure Rust backend on modern CPUs, consider building with

RUSTFLAGS="-Ctarget-cpu=sandybridge -Ctarget-feature=+aes,+sse2,+sse4.1,+ssse3"

to speed up AES encryption/decryption. This would be no longer necessary when aes-gcm supports automatic CPU detection.

WASM compatibility

It's also possible to build to the wasm32-unknown-unknown target with the pure Rust backend. Check out this repo for more details.

Security

Why AES-GCM-256 and HKDF-SHA256

AEAD scheme like AES-GCM-256 should be your first option for symmetric ciphers, with unique IVs in each encryption.

For key derivation functions on shared points between two asymmetric keys, HKDFs are proven to be more secure than simple hash functions like SHA256.

Cross-language compatibility

All functionalities are mutually checked among different languages: Python, Rust, JavaScript and Golang.

Security audit

Following dependencies are audited:

• aes-gcm
• OpenSSL

Benchmark

The result shows that the pure Rust backend is around 20% ~ 50% slower compared to OpenSSL on MacBook Pro mid-2015 (2.8 GHz Quad-Core Intel Core i7).

OpenSSL backend

$ cargo bench --no-default-features --features openssl
encrypt 100M            time:   [110.25 ms 115.77 ms 120.22 ms]
                        change: [-10.123% -3.0504% +4.2342%] (p = 0.44 > 0.05)
                        No change in performance detected.

encrypt 200M            time:   [435.22 ms 450.50 ms 472.17 ms]
                        change: [-7.5254% +3.6572% +14.508%] (p = 0.56 > 0.05)
                        No change in performance detected.
Found 1 outliers among 10 measurements (10.00%)
  1 (10.00%) high mild

decrypt 100M            time:   [60.439 ms 66.276 ms 70.959 ms]
                        change: [+0.1986% +7.7620% +15.995%] (p = 0.08 > 0.05)
                        No change in performance detected.

decrypt 200M            time:   [182.10 ms 185.85 ms 190.63 ms]
                        change: [-4.8452% +5.2114% +16.370%] (p = 0.40 > 0.05)
                        No change in performance detected.
Found 1 outliers among 10 measurements (10.00%)
  1 (10.00%) high severe

Pure Rust backend

$ export RUSTFLAGS="-Ctarget-cpu=sandybridge -Ctarget-feature=+aes,+sse2,+sse4.1,+ssse3"
$ cargo bench --no-default-features --features pure
encrypt 100M            time:   [196.85 ms 201.97 ms 205.67 ms]
                        change: [-9.8235% -7.9098% -5.9849%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 1 outliers among 10 measurements (10.00%)
  1 (10.00%) low severe

encrypt 200M            time:   [554.62 ms 585.01 ms 599.71 ms]
                        change: [-15.036% -11.698% -8.6460%] (p = 0.00 < 0.05)
                        Performance has improved.

decrypt 100M            time:   [131.26 ms 134.39 ms 140.54 ms]
                        change: [-3.9509% +2.9485% +10.198%] (p = 0.42 > 0.05)
                        No change in performance detected.

decrypt 200M            time:   [288.13 ms 296.64 ms 311.78 ms]
                        change: [-16.887% -13.038% -8.6679%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 1 outliers among 10 measurements (10.00%)
  1 (10.00%) high mild

Release Notes

0.2.2

• Bump dependencies
• Migrate to edition 2021

0.2.1

• Revamp error handling

0.2.0

• Revamp documentation
• Optional pure Rust AES backend
• WASM compatibility

0.1.1 ~ 0.1.5

• Bump dependencies
• Update documentation
• Fix error handling

0.1.0

• First beta version release