Module evercrypt::ecdh

ECDH

This module implements an agile API for ECDH on P256 and x25519.

Usage

use evercrypt::ecdh::{self, Mode};

// P256
let public = [0x04, 0x62, 0xd5, 0xbd, 0x33, 0x72, 0xaf, 0x75, 0xfe, 0x85, 0xa0, 0x40, 0x71, 0x5d, 0x0f, 0x50, 0x24, 0x28, 0xe0, 0x70, 0x46, 0x86, 0x8b, 0x0b, 0xfd, 0xfa, 0x61, 0xd7, 0x31, 0xaf, 0xe4, 0x4f, 0x26, 0xac, 0x33, 0x3a, 0x93, 0xa9, 0xe7, 0x0a, 0x81, 0xcd, 0x5a, 0x95, 0xb5, 0xbf, 0x8d, 0x13, 0x99, 0x0e, 0xb7, 0x41, 0xc8, 0xc3, 0x88, 0x72, 0xb4, 0xa0, 0x7d, 0x27, 0x5a, 0x01, 0x4e, 0x30, 0xcf];
let private = [0x06, 0x12, 0x46, 0x5c, 0x89, 0xa0, 0x23, 0xab, 0x17, 0x85, 0x5b, 0x0a, 0x6b, 0xce, 0xbf, 0xd3, 0xfe, 0xbb, 0x53, 0xae, 0xf8, 0x41, 0x38, 0x64, 0x7b, 0x53, 0x52, 0xe0, 0x2c, 0x10, 0xc3, 0x46];
let expected_result = [0x53, 0x02, 0x0d, 0x90, 0x8b, 0x02, 0x19, 0x32, 0x8b, 0x65, 0x8b, 0x52, 0x5f, 0x26, 0x78, 0x0e, 0x3a, 0xe1, 0x2b, 0xcd, 0x95, 0x2b, 0xb2, 0x5a, 0x93, 0xbc, 0x08, 0x95, 0xe1, 0x71, 0x42, 0x85];

let result = match ecdh::derive(Mode::P256, &public, &private) {
    Ok(r) => r,
    Err(e) => panic!("P256 derive failed.\n{:?}", e),
};
assert_eq!(expected_result[..], result[..32]);

let _result = match ecdh::derive_base(Mode::P256, &private) {
    Ok(r) => r,
    Err(e) => panic!("P256 derive failed.\n{:?}", e),
};

// x25519
let public = [0x50, 0x4a, 0x36, 0x99, 0x9f, 0x48, 0x9c, 0xd2, 0xfd, 0xbc, 0x08, 0xba, 0xff, 0x3d, 0x88, 0xfa, 0x00, 0x56, 0x9b, 0xa9, 0x86, 0xcb, 0xa2, 0x25, 0x48, 0xff, 0xde, 0x80, 0xf9, 0x80, 0x68, 0x29];
let private = [0xc8, 0xa9, 0xd5, 0xa9, 0x10, 0x91, 0xad, 0x85, 0x1c, 0x66, 0x8b, 0x07, 0x36, 0xc1, 0xc9, 0xa0, 0x29, 0x36, 0xc0, 0xd3, 0xad, 0x62, 0x67, 0x08, 0x58, 0x08, 0x80, 0x47, 0xba, 0x05, 0x74, 0x75];
let expected_result = [0x43, 0x6a, 0x2c, 0x04, 0x0c, 0xf4, 0x5f, 0xea, 0x9b, 0x29, 0xa0, 0xcb, 0x81, 0xb1, 0xf4, 0x14, 0x58, 0xf8, 0x63, 0xd0, 0xd6, 0x1b, 0x45, 0x3d, 0x0a, 0x98, 0x27, 0x20, 0xd6, 0xd6, 0x13, 0x20];

let result = match ecdh::derive(Mode::X25519, &public, &private) {
    Ok(r) => r,
    Err(e) => panic!("x25519 derive failed.\n{:?}", e),
};
assert_eq!(expected_result[..], result[..]);

let _result = match ecdh::derive_base(Mode::X25519, &private) {
    Ok(r) => r,
    Err(e) => panic!("x25519 derive failed.\n{:?}", e),
};

Enums

Error

Mode

ECDH algorithm.

Functions

derive

Derive the ECDH shared secret. Returns Ok(p * s) on the provided curve (mode) or an error.

derive_base

Returns Ok(base_point * s) on the provided curve (mode) or an error.

key_gen

Generate a random Scalar on the given curve.