我正在尝试在我的节点应用程序中实现基本的加密功能。问题在于我发现的几乎所有示例和指南（包括Node docs上的示例和指南）都使用未经身份验证的密码。
所以，我希望有人可以看看我拥有的东西，并让我知道我是在做愚蠢的事情还是让自己不受任何明显的旁道攻击。
我运行此代码时，除一种情况外，一切都按预期工作（即应该通过的测试和应该失败的测试）。
似乎我可以将任意数量的数据附加到密文的末尾，并且消息仍会解密而没有错误。我认为，对密文进行任何修改后，经过身份验证的加密系统应该会失败。您可以通过将tweakCharAt变量更改为类似100的值来进行测试。我做错了吗？这是某种预期的行为吗？
const { createCipheriv, createDecipheriv, randomBytes, randomFillSync } = require('crypto');
const { promisify } = require('util');
const randomBytesPromise = promisify(randomBytes);
const algorithm = 'chacha20-poly1305';
const ivLen = 12; // IETF version of ChaCha20-Poly1305 uses a 96 bit (12 byte) nonce
const authTagLength = 16; // Poly1305 generates a 128 bit (16 byte) authentication tag
// Takes a Node Transform stream (like Cipher and Decipher) + some data and returns a Promise
const streamPromise = (stream, data) => new Promise((resolve, reject) => {
// Create an array to hold the chunks of binary data
const chunks = [];
// Setup stream event handlers
// See: https://nodejs.org/api/crypto.html#crypto_class_cipher
stream.on('readable', () => {
let chunk;
// eslint-disable-next-line no-cond-assign
while ((chunk = stream.read()) !== null) {
chunks.push(chunk);
}
});
stream.on('end', () => { resolve(Buffer.concat(chunks)); });
stream.on('error', (error) => { reject(error); });
// Write the given data to the stream and then close it up
stream.write(data);
stream.end();
});
const encrypt = (plainText, key, authenticatedData = Buffer.alloc(0)) => (
randomBytesPromise(ivLen)
.then((rand) => {
const iv = rand;
const cipher = createCipheriv(algorithm, key, iv, { authTagLength });
cipher.setAAD(authenticatedData);
return streamPromise(cipher, plainText)
.then(encMessage => [iv, authenticatedData, cipher.getAuthTag(), encMessage]);
})
.then(parts => parts.map(buffer => buffer.toString('base64')).join(':'))
);
const decrypt = (cipherText, key) => {
const [
iv,
authenticatedData,
authTag,
message
] = cipherText.split(':').map(string => Buffer.from(string, 'base64'));
const decipher = createDecipheriv(algorithm, key, iv, { authTagLength });
decipher.setAAD(authenticatedData);
decipher.setAuthTag(authTag);
return streamPromise(decipher, message);
};
const test = (message, keyBuffer, authenticatedData, testNum, tamperWithCipherText = false) => (
encrypt(message, keyBuffer, authenticatedData)
.then((cipherText) => {
console.log(testNum + ' cipher text: ', cipherText);
let newCipherText = cipherText;
if (tamperWithCipherText) {
const tweakCharAt = 30; // 100;
newCipherText = newCipherText.substring(0, tweakCharAt)
+ '0' // '==/I5QUaGV'
+ newCipherText.substring(tweakCharAt + 1);
console.log(testNum + ' new cipher text: ', newCipherText);
}
console.log(testNum + ' AAD: ', Buffer.from(newCipherText.split(':')[1], 'base64').toString('utf8'));
return decrypt(newCipherText, keyBuffer);
})
.then((plainText) => {
console.log(testNum + ' plain text: ', plainText.toString('utf8') + '\n');
})
.catch((error) => {
console.error(testNum, error);
})
);
// Run some tests
const key = Buffer.allocUnsafe(32);
randomFillSync(key);
const testMessage = 'Top secret message';
const authData = Buffer.from('AAD data here', 'utf8');
// Test without authenticated data
test(testMessage, key, undefined, 1); // should work
test(testMessage, key, undefined, 2, true); // should error
// Test with authenticated data
test(testMessage, key, authData, 3); // should work
test(testMessage, key, authData, 4, true); // should error
这是在节点12中运行上述代码的一些输出，这些设置具有不同的修改密文设置。
1 cipher text: /mFoBKirqH8DZ3Wv::JayX8aiYi77ApLyhI6yYfw==:uBOj318Zf9M2qaBgIkiEX2MC
1 AAD:
1 plain text: Top secret message
2 cipher text: QnEbbrFpYhTLPuhk::owdqDGokK9WoXE0Od5DDTQ==:QROQ3/Q1qhKz4/FSQbwFuVoG
2 new cipher text: QnEbbrFpYhTLPuhk::owdqDGokK9Wo0E0Od5DDTQ==:QROQ3/Q1qhKz4/FSQbwFuVoG
2 AAD:
2 Error: Unsupported state or unable to authenticate data
at Decipheriv._flush (internal/crypto/cipher.js:144:29)
at Decipheriv.prefinish (_stream_transform.js:140:10)
at Decipheriv.emit (events.js:200:13)
...
3 cipher text: 36cf2xXpsZnfFn+I:QUFEIGRhdGEgaGVyZQ==:NRRNaY9yAJ2yu7z4Nh0+Tw==:ZdY9xtFh0zcXgDcydG+zEhug
3 AAD: AAD data here
3 plain text: Top secret message
4 cipher text: HWA0BWBPHe/3kFps:QUFEIGRhdGEgaGVyZQ==:w6s+CYMeU0SNoCtgbeRBsw==:2TOwGnbT2T1ZZ8qKe90BU2VJ
4 new cipher text: HWA0BWBPHe/3kFps:QUFEIGRhdGEga0VyZQ==:w6s+CYMeU0SNoCtgbeRBsw==:2TOwGnbT2T1ZZ8qKe90BU2VJ
4 AAD: AAD data kEre
4 Error: Unsupported state or unable to authenticate data
at Decipheriv._flush (internal/crypto/cipher.js:144:29)
at Decipheriv.prefinish (_stream_transform.js:140:10)
at Decipheriv.emit (events.js:200:13)
...
1 cipher text: cwtqwgX2mB5gmPh4::I2yPh0xoorrvVU+7edM1Ww==:V9qnpa25HEPw/v6zBc03tpYz
1 AAD:
1 plain text: Top secret message
2 cipher text: fe4spIYdiJDyIaUo::unK0AA6vI9bTDDVN/qm3Gw==:dE9bRpOi99ntKviitH4QdkGR
2 new cipher text: fe4spIYdiJDyIaUo::unK0AA6vI9bTDDVN/qm3Gw==:dE9bRpOi99ntKviitH4QdkGRA
2 AAD:
2 plain text: Top secret message
3 cipher text: zzDP/FB3u4svhDoC:QUFEIGRhdGEgaGVyZQ==:GExIqrogg8Dm8ifQUhVxJg==:VH46trhHXsmcafPdImgArorb
3 AAD: AAD data here
3 plain text: Top secret message
4 cipher text: TQE0QC8wUAElPYIC:QUFEIGRhdGEgaGVyZQ==:TpWkCLskrnRrQOykke+FoA==:YF3WEywHVzPNzuTg7UYKD3Ja
4 new cipher text: TQE0QC8wUAElPYIC:QUFEIGRhdGEgaGVyZQ==:TpWkCLskrnRrQOykke+FoA==:YF3WEywHVzPNzuTg7UYKD3JaA
4 AAD: AAD data here
4 plain text: Top secret message
1 cipher text: 35ddfd0541be72780793894b::dc9ea755fbf00ee1bd9b737727b912af:5cd46cad985c2da058fa51967a675cb9bda6
1 AAD:
1 plain text: Top secret message
2 cipher text: 0da4c80d45610cd3717e8497::0fcdea1d4ccfb9cb4347491430ccc4b3:3060d55728bc8ab2f75f80ce27ebe06f813e
2 new cipher text: 0da4c80d45610cd3717e8497::0fcdea1d4ccfb9cb4347491430ccc4b3:3060d55728bc8ab2f75f80ce27ebe06f813eA
2 AAD:
2 plain text: Top secret message
3 cipher text: f6ae6d9a72139b8611dd3798:41414420646174612068657265:f00d9d987f94038334603165605ce966:c6e635d8d81da0badd0ee98d64e007308853
3 AAD: AAD data here
3 plain text: Top secret message
4 cipher text: a66fab00b07bc963cff3c721:41414420646174612068657265:05ed29d50a426df3b5a3616c7a467703:1b9d88bfdff01f5eacad9ce7cd9a117d6b08
4 new cipher text: a66fab00b07bc963cff3c721:41414420646174612068657265:05ed29d50a426df3b5a3616c7a467703:1b9d88bfdff01f5eacad9ce7cd9a117d6b08A
4 AAD: AAD data here
4 plain text: Top secret message