Browser/NodeJSでSHAダイジェストを行うためのライブラリ

digest+flow.js

// Chrome以外でも利用する場合は以下をimportすること
// import 'webcrypto-shim';

import JSSHA from 'jssha';

function webCryptoHex(buffer: Uint8Array): string {
    const hexCodes = [];
    const view = new DataView(buffer);
    for (let i = 0; i < view.byteLength; i += 4) {
        const value = view.getUint32(i);
        const stringValue = value.toString(16);
        const padding = '00000000';
        const paddedValue = (padding + stringValue).slice(-padding.length);
        hexCodes.push(paddedValue);
    }
    return hexCodes.join('');
}

type WebCryptoDigestAlgorithm = 'SHA-1' | 'SHA-256' | 'SHA-512';
function webCryptoDigestString(algorithm: WebCryptoDigestAlgorithm, str: string): Promise<string> {
    const buffer = new TextEncoder('utf-8').encode(str);
    return crypto.subtle.digest(algorithm, buffer).then((hash) => webCryptoHex(hash));
}

type NodeJSDigestAlgorithm = 'sha1' | 'sha256' | 'sha512';
function nodejsDigestString(algorithm: NodeJSDigestAlgorithm, str: string): Promise<string> {
    return new Promise((resolve) => {
        const crypto = require('crypto'); // eslint-disable-line
        const shasum = crypto.createHash(algorithm);
        shasum.update(str);
        resolve(shasum.digest('hex'));
    });
}

type jsSHADigestAlgorithm = 'SHA-1' | 'SHA-256' | 'SHA-512';
function jsSHADigestString(algorithm: jsSHADigestAlgorithm, str: string): Promise<string> {
    return new Promise((resolve) => {
        const shasum = new JSSHA(algorithm, 'TEXT');
        shasum.update(str);
        resolve(shasum.getHash('HEX'));
    });
}

function isNodeJS(): boolean {
    return typeof window === 'undefined' && typeof process === 'object';
}

function hasWebCrypto(): boolean {
    return typeof window !== 'undefined' && typeof window.crypto !== 'undefined';
}

function isSecureOrigin(): boolean {
    if (typeof window !== 'undefined' && typeof window.isSecureContext === 'boolean') {
        return window.isSecureContext;
    }

    return typeof window !== 'undefined' && window.location.protocol === 'https:';
}

export function sha1(str: string): Promise<string> {
    if (isNodeJS()) {
        return nodejsDigestString('sha1', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-1', str);
    }

    return jsSHADigestString('SHA-1', str);
}

export function sha256(str: string): Promise<string> {
    if (isNodeJS()) {
        return nodejsDigestString('sha256', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-256', str);
    }

    return jsSHADigestString('SHA-256', str);
}

export function sha512(str: string): Promise<string> {
    if (isNodeJS()) {
        return nodejsDigestString('sha512', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-512', str);
    }

    return jsSHADigestString('SHA-512', str);
}

digest.js

// Chrome以外でも利用する場合は以下をimportすること
// import 'webcrypto-shim';

import JSSHA from 'jssha';

function webCryptoHex(buffer) {
    const hexCodes = [];
    const view = new DataView(buffer);
    for (let i = 0; i < view.byteLength; i += 4) {
        const value = view.getUint32(i);
        const stringValue = value.toString(16);
        const padding = '00000000';
        const paddedValue = (padding + stringValue).slice(-padding.length);
        hexCodes.push(paddedValue);
    }
    return hexCodes.join('');
}

function webCryptoDigestString(algorithm, str) {
    const buffer = new TextEncoder('utf-8').encode(str);
    return crypto.subtle.digest(algorithm, buffer).then(hash => webCryptoHex(hash));
}

function nodejsDigestString(algorithm, str) {
    return new Promise(resolve => {
        const crypto = require('crypto'); // eslint-disable-line
        const shasum = crypto.createHash(algorithm);
        shasum.update(str);
        resolve(shasum.digest('hex'));
    });
}

function jsSHADigestString(algorithm, str) {
    return new Promise(resolve => {
        const shasum = new JSSHA(algorithm, 'TEXT');
        shasum.update(str);
        resolve(shasum.getHash('HEX'));
    });
}

function isNodeJS() {
    return typeof window === 'undefined' && typeof process === 'object';
}

function hasWebCrypto() {
    return typeof window !== 'undefined' && typeof window.crypto !== 'undefined';
}

function isSecureOrigin() {
    if (typeof window !== 'undefined' && typeof window.isSecureContext === 'boolean') {
        return window.isSecureContext;
    }

    return typeof window !== 'undefined' && window.location.protocol === 'https:';
}

export function sha1(str) {
    if (isNodeJS()) {
        return nodejsDigestString('sha1', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-1', str);
    }

    return jsSHADigestString('SHA-1', str);
}

export function sha256(str) {
    if (isNodeJS()) {
        return nodejsDigestString('sha256', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-256', str);
    }

    return jsSHADigestString('SHA-256', str);
}

export function sha512(str) {
    if (isNodeJS()) {
        return nodejsDigestString('sha512', str);
    }

    if (isSecureOrigin() && hasWebCrypto()) {
        return webCryptoDigestString('SHA-512', str);
    }

    return jsSHADigestString('SHA-512', str);
}