nodejs module for AES-CBC stream encryption and decryption, with support for partial decrypts.
npm install aes-cbc-stream
const fs = require('fs'),
crypto = require('crypto');
const { EncryptStream } = require('aes-cbc-stream')
// Encrypt `data.bin`.
const inputStream = fs.createReadStream('data.bin');
const outputStream = fs.createWriteStream('encrypted.bin');
const encryptKey = crypto.randomBytes(32);
inputStream
.pipe(new EncryptStream({
key: encryptKey,
cipherName: 'aes-256-cbc'
}))
.pipe(outputStream);
outputStream.on('finish', function() {
console.log("File encrypted!");
});
const fs = require('fs'),
crypto = require('crypto');
// The desired range (inclusive) of decrypted data.
const start = 100, end = 300;
// Find the parameters to pass to DecryptStream with calculateParams().
const {
skipPrefixLength,
encryptedStartIndex,
encryptedEndIndex,
wantedOutputLength
} = DecryptStream.calculateParams({
decryptedStartIndex: start,
decryptedEndIndex: end
});
const inputStream = fs.createReadStream('encrypted.bin');
const outputStream = fs.createWriteStream('decrypted.bin');
const decryptStream = new DecryptStream({
// The key and cipher used to encrypt the file from the previous example.
key: encryptKey,
cipherName: 'aes-256-cbc',
// Start and end index at block boundaries, with a preceding IV block.
encryptedStartIndex,
encryptedEndIndex,
// The number of initial decrypted bytes to skip. If `start` does not
// start at a block boundary, this is a non-zero number in order to
// return the requested range.
skipPrefixLength,
// The desired output length.
wantedOutputLength
});
inputStream.pipe(decryptStream)
.pipe(outputStream);
outputStream.on('finish', () => {
console.log("Decryption done!");
});