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@bbstilson
Last active August 10, 2022 22:56
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const crypto = require('crypto');
const fs = require('fs');
const path = require('path');
const zlib = require('zlib');
const getCipherKey = require('./getCipherKey');
function decrypt({ file, password }) {
// First, get the initialization vector from the file.
const readInitVect = fs.createReadStream(file, { end: 15 });
let initVect;
readInitVect.on('data', (chunk) => {
initVect = chunk;
});
// Once we’ve got the initialization vector, we can decrypt the file.
readInitVect.on('close', () => {
const cipherKey = getCipherKey(password);
const readStream = fs.createReadStream(file, { start: 16 });
const decipher = crypto.createDecipheriv('aes256', cipherKey, initVect);
const unzip = zlib.createUnzip();
const writeStream = fs.createWriteStream(file + '.unenc');
readStream
.pipe(decipher)
.pipe(unzip)
.pipe(writeStream);
});
}
@haha861924
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haha861924 commented Jun 24, 2021

hello ,I use your methods ,but I get error , I find this is not work , do you know why?
let initVect; readInitVect.on('data', (chunk) => { initVect = chunk; });
this is how do I try and a question , please help me
https://stackoverflow.com/questions/68118250/decrypt-file-use-aes-256-cbc-node-js-iv-undefind

@bbstilson
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Added a response on StackOverFlow. Let's chat there so it may help others!

@SupratikR
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Hi, I was trying out your encryption and decryption code, but it seems the decryption is giving an error

events.js:292
throw er; // Unhandled 'error' event
^

Error: incorrect header check
at Zlib.zlibOnError [as onerror] (zlib.js:182:17)
Emitted 'error' event on Unzip instance at:
at Unzip.onerror (internal/streams/readable.js:760:14)
at Unzip.emit (events.js:315:20)
at emitErrorNT (internal/streams/destroy.js:106:8)
at emitErrorCloseNT (internal/streams/destroy.js:74:3)
at processTicksAndRejections (internal/process/task_queues.js:80:21) {
errno: -3,
code: 'Z_DATA_ERROR'
}

can you help on this or have an idea as to what could be the issue?

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