使用WebCrypto API从私钥生成公钥

Question

我正在使用Web Crypto API，并正在使用generateKey函数生成RSA密钥对。由于我的代码中存在一些错误，因此我为某些用户删除了公钥。我想知道是否有任何方法可以从私钥中生成公钥？我知道使用ssh键很容易。这是我用于生成RSA密钥对的示例代码：

const generateRSAKeys = (): Promise<CryptoKeyPair> => {
    return crypto.subtle.generateKey(
    {
        name: 'RSA-OAEP',
        modulusLength: 2048
        publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
        hash: { name: 'SHA-512' },
    },
    true,
    ['encrypt', 'decrypt', 'wrapKey', 'unwrapKey'],
);

Answer 1

您可以通过导出私钥并导入导出的数据（例如公共数据）来实现此目的

const keys = await crypto.subtle.generateKey(
  {
    name: 'RSA-OAEP',
    modulusLength: 2048,
    publicExponent: new Uint8Array([0x01, 0x00, 0x01]),
    hash: { name: 'SHA-512' },
  },
  true,
  ['encrypt', 'decrypt', 'wrapKey', 'unwrapKey'],
);

// export private key to JWK
const jwk = await crypto.subtle.exportKey("jwk", keys.privateKey);

// remove private data from JWK
delete jwk.d;
delete jwk.dp;
delete jwk.dq;
delete jwk.q;
delete jwk.qi;
jwk.key_ops = ["encrypt", "wrapKey"];

// import public key
const publicKey = await crypto.subtle.importKey("jwk", jwk, { name: "RSA-OAEP", 
hash: "SHA-512" }, true, ["encrypt", "wrapKey"]);

console.log(publicKey)