hash.ts

import { encode } from 'https://deno.land/std@0.143.0/encoding/hex.ts';
import { decode } from 'https://deno.land/std@0.179.0/encoding/base64.ts';

export async function hashString(
  algorithm: 'SHA-1' | 'SHA-256' | 'SHA-512',
  d: string | Uint8Array,
): Promise<string> {
  const data = typeof d === 'string' ? new TextEncoder().encode(d) : d;
  const hashRes = new Uint8Array(
    await crypto.subtle.digest(
      algorithm,
      data,
    ),
  );
  return hexString(hashRes);
}

/**
 * 将二进制数据储存为 HEX (16 进制字符串)
 * @param data 二进制数据
 * @returns HEX (16 进制字符串)
 */
export function hexString(data: Uint8Array): string {
  let s = '';
  for (const d of encode(data)) {
    s += String.fromCodePoint(d);
  }
  return s;
}

export async function hmac(
  key: {
    hash: 'SHA-1' | 'SHA-256' | 'SHA-512';
    /** secret key */
    s: string | Uint8Array;
  } | CryptoKey,
  /** data */
  d: string | Uint8Array,
): Promise<Uint8Array> {
  const textEncoder = new TextEncoder();

  let cryptoKey: CryptoKey;
  if (key instanceof CryptoKey) {
    cryptoKey = key;
  } else {
    const { s, hash } = key;
    const keyData = typeof s === 'string' ? textEncoder.encode(s) : s;
    cryptoKey = await crypto.subtle.importKey(
      'raw',
      keyData,
      { name: 'HMAC', hash },
      true,
      ['sign', 'verify'],
    );
  }

  const data = typeof d === 'string' ? textEncoder.encode(d) : d;

  const res = new Uint8Array(
    await crypto.subtle.sign(
      'HMAC',
      cryptoKey,
      data,
    ),
  );

  return res;
}

/**
 * Sign data with RSA
 * - only pkcs8
 * - only RSASSA-PKCS1-v1_5
 * @param key
 * @param d
 * @returns
 */
export async function rasSign(
  key: {
    hash: 'SHA-256' | 'SHA-512';
    /** secret key */
    s: string | Uint8Array;
  } | CryptoKey,
  /** data */
  d: string | Uint8Array,
): Promise<Uint8Array> {
  let cryptoKey: CryptoKey;
  if (key instanceof CryptoKey) {
    cryptoKey = key;
  } else {
    const { s, hash } = key;
    const keyData = typeof s === 'string' ? decode(s) : s;
    cryptoKey = await crypto.subtle.importKey(
      'pkcs8',
      keyData,
      { name: 'RSASSA-PKCS1-v1_5', hash: { name: hash } },
      true,
      ['sign'],
    );
  }

  const data = typeof d === 'string' ? new TextEncoder().encode(d) : d;

  const res = new Uint8Array(
    await crypto.subtle.sign(
      'RSASSA-PKCS1-v1_5',
      cryptoKey,
      data,
    ),
  );

  return res;
}