How can I do Base64 encoding in Node.js? – Dev

The best answers to the question “How can I do Base64 encoding in Node.js?” in the category Dev.

QUESTION:

Does Node.js have built-in Base64 encoding yet?

The reason why I ask this is that final() from crypto can only output hexadecimal, binary or ASCII data. For example:

var cipher = crypto.createCipheriv('des-ede3-cbc', encryption_key, iv);
var ciph = cipher.update(plaintext, 'utf8', 'hex');
ciph += cipher.final('hex');

var decipher = crypto.createDecipheriv('des-ede3-cbc', encryption_key, iv);
var txt = decipher.update(ciph, 'hex', 'utf8');
txt += decipher.final('utf8');

According to the documentation, update() can output Base64-encoded data. However, final() doesn’t support Base64. I tried and it will break.

If I do this:

var ciph = cipher.update(plaintext, 'utf8', 'base64');
    ciph += cipher.final('hex');

Then what should I use for decryption? Hexadecimal or Base64?

Therefore, I’m looking for a function to Base64-encode my encrypted hexadecimal output.

ANSWER:

The accepted answer previously contained new Buffer(), which is considered a security issue in Node.js versions greater than 6 (although it seems likely for this use case that the input can always be coerced to a string).

The Buffer constructor is deprecated according to the documentation.

Here is an example of a vulnerability that can result from using it in the ws library.

The code snippets should read:

console.log(Buffer.from("Hello World").toString('base64'));
console.log(Buffer.from("SGVsbG8gV29ybGQ=", 'base64').toString('ascii'));

After this answer was written, it has been updated and now matches this.

ANSWER:

Buffers can be used for taking a string or piece of data and doing Base64 encoding of the result. For example:

> console.log(Buffer.from("Hello World").toString('base64'));
SGVsbG8gV29ybGQ=
> console.log(Buffer.from("SGVsbG8gV29ybGQ=", 'base64').toString('ascii'))
Hello World

Buffers are a global object, so no require is needed. Buffers created with strings can take an optional encoding parameter to specify what encoding the string is in. The available toString and Buffer constructor encodings are as follows:

‘ascii’ – for 7 bit ASCII data only. This encoding method is very
fast, and will strip the high bit if set.

‘utf8’ – Multi byte encoded
Unicode characters. Many web pages and other document formats use
UTF-8.

‘ucs2’ – 2-bytes, little endian encoded Unicode characters. It
can encode only BMP(Basic Multilingual Plane, U+0000 – U+FFFF).

‘base64’ – Base64 string encoding.

‘binary’ – A way of encoding raw
binary data into strings by using only the first 8 bits of each
character. This encoding method is deprecated and should be avoided in
favor of Buffer objects where possible. This encoding will be removed
in future versions of Node.

ANSWER:

Buffers can be used for taking a string or piece of data and doing Base64 encoding of the result. For example:

You can install Buffer via npm like: npm i buffer --save

You can use this in your js file like this:

var buffer = require('buffer/').Buffer;

->> console.log(buffer.from("Hello Vishal Thakur").toString('base64'));
SGVsbG8gVmlzaGFsIFRoYWt1cg==  // Result

->> console.log(buffer.from("SGVsbG8gVmlzaGFsIFRoYWt1cg==", 'base64').toString('ascii'))
Hello Vishal Thakur   // Result

ANSWER:

crypto now supports Base64 (reference):

cipher.final('base64')

So you could simply do:

var cipher = crypto.createCipheriv('des-ede3-cbc', encryption_key, iv);
var ciph = cipher.update(plaintext, 'utf8', 'base64');
ciph += cipher.final('base64');

var decipher = crypto.createDecipheriv('des-ede3-cbc', encryption_key, iv);
var txt = decipher.update(ciph, 'base64', 'utf8');
txt += decipher.final('utf8');