node.js - NodeJS加密无法验证Web加密API创建的签名

我在验证由Web Crypto API创建的签名时遇到麻烦。

这是我用来在浏览器中生成RSA密钥的代码：

let keys;

const generateKeys = async () => {
  const options = {
    name: 'RSASSA-PKCS1-v1_5',
    modulusLength: 2048,
    publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
    hash: { name: 'SHA-256' },
  };

  keys = await window.crypto.subtle.generateKey(
    options,
    false, // non-exportable (public key still exportable)
    ['sign', 'verify'],
  );
};

并导出公钥：

const exportPublicKey = async () => {
  const publicKey = await window.crypto.subtle.exportKey('spki', keys.publicKey);

  let body = window.btoa(String.fromCharCode(...new Uint8Array(publicKey)));
  body = body.match(/.{1,64}/g).join('\n');

  return `-----BEGIN PUBLIC KEY-----\n${body}\n-----END PUBLIC KEY-----`;

  // Output:
  //
  // -----BEGIN PUBLIC KEY-----
  // MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAx7J3SUG4sq/HSGIaGZWY
  // 8b26cfEpVFYHoDUDUORIJzA/fLE9aj+uOKpGUTSfW69rMm7DAOLDz05KaEJJSI5+
  // YbDPr2S82A2ByHHQt+Vu168sGz4noXTTSX2HIdVutaR/IJ0a5pNOa1vRR4MUW/ZO
  // YaRir3yC5YXgcFLwwQaifNZ3lZ7WndbYEjTGOcieQQ81IUP2221PZCJI52S95nYm
  // VfslsLiPhOFH7XhGSqelGYDi0cKyl0p6dKvYxFswfKKLTuWnu2BEFLjVq4S5Y9Ob
  // SGm0KL/8g7pAqjac2sMzzhHtxZ+7k8tynzAf4slJJhHMm5U4DcSelTe5zOkprCJg
  // muyv0H1Acb3tfXsBwfURjiE0cvSMhfum5I5epF+f139tsr1zNF24F2WgvEZZbXcG
  // g1LveGCJ/0BY0pzE71DU2SYiUhl+HGDv2u32vJO80jCDf2lu7izEt544a+XE+2X0
  // zVpwjNQGa2Nd4ApGosa1fbcS5MsEdbyrjMf80SAmOeb9g3y5Zt2MY7M0Njxbvmmd
  // mF20PkklpH0L01lhg2AGma4o4ojolYHzDoM5a531xTw1fZIdgbSTowz0SlAHAKD3
  // c2KCCsKlBbFcqy4q7yNX63SqmI3sNA3kTH9CQJdBloRvV103Le9C0iY8CAWQmow5
  // N/sDJUabgOMqe9yopSjb7LUCAwEAAQ==
  // -----END PUBLIC KEY-----
};

签名消息：

const generateHash = async (message) => {
  const encoder = new TextEncoder();
  const buffer = encoder.encode(message);

  const digest = await window.crypto.subtle.digest('SHA-256', buffer);
  return digest;
};

const signMessage = async (message) => {
  const { privateKey } = keys;
  const digest = await generateHash(message);
  const signature = await window.crypto.subtle.sign('RSASSA-PKCS1-v1_5', privateKey, digest);
  return signature;
};

要在浏览器中验证消息：

const verifyMessage = async (signature, message) => {
  const { publicKey } = keys;
  const digest = await generateHash(message);
  const result = await window.crypto.subtle.verify('RSASSA-PKCS1-v1_5', publicKey, signature, digest);
  return result;
};

创建密钥后，将导出公共密钥并将其发送到服务器。后来：

const message = 'test';
const signature = await signMessage(message);
await verifyMessage(signature, message); // true

sendToServer(message, bufferToHex(signature));

由于签名是ArrayBuffer，因此我使用以下代码将其转换为十六进制：

const bufferToHex = input => [...new Uint8Array(input)]
  .map(v => v.toString(16).padStart(2, '0')).join('');

在服务器上（NodeJS 8.11.0）：

const publicKey = getPublicKey(userId);

const verifier = crypto.createVerify('RSA-SHA256');
verifier.update(message, 'utf-8');

const sigBuf = Buffer.from(signature, 'hex');
verifier.verify(publicKey, sigBuf); // false

我已经追踪这个问题好几天了，但似乎无法弄清楚。我已经尝试RSA-SHA256和sha256WithRSAEncryption进行验证都没有用。此外，不会引发任何错误。任何帮助将不胜感激！

最佳答案

因此，我不完全理解为什么会这样，但是要解决此问题，我需要将SHA哈希从ArrayBuffer转换为十六进制字符串，然后使用TextEncoder读回数组缓冲区。

const generateHash = async (message) => {
  const encoder = new TextEncoder();
  const buffer = encoder.encode(message);

  const digest = await window.crypto.subtle.digest('SHA-256', buffer);

  // Convert to hex string
  return [...new Uint8Array(digest)]
    .map(v => v.toString(16).padStart(2, '0')).join('');;
};

然后在签名时：

const signMessage = async (message) => {
  const encoder = new TextEncoder();
  const { privateKey } = keys;
  const digest = await generateHash(message);
  const signature = await window.crypto.subtle.sign('RSASSA-PKCS1-v1_5', privateKey, encoder.encode(digest));
  return signature;
};

签名不再在客户端上验证，而是在节点上验证。 ♂‍♂️