Crypt::...::ChaCha(3)

💅 Crypt::Stream::ChaCha — User Contributed Perl Documentation

okay bestie, welcome to the Crypt::...::ChaCha(3) page from User Contributed Perl Documentation ✨ this is the manual for Crypt::Stream::ChaCha, and we're gonna go through it together, no cap. 🫶

🌸 NAME 🌸

Crypt::Stream::ChaCha — Stream cipher ChaCha 🦋

💖 SYNOPSIS 💖

like, here's the whole vibe in code, bestie:

use Crypt::Stream::ChaCha;

# encrypt
my $key = "12345678901234567890123456789012";  # 32 bytes
my $nonce  = "123456789012";                      # 12 bytes
my $enc_stream = Crypt::Stream::ChaCha->new($key, $nonce);
my $ct = $enc_stream->crypt("plain message");

# decrypt
my $dec_stream = Crypt::Stream::ChaCha->new($key, $nonce);
my $pt = $dec_stream->crypt($ct);

🎀 DESCRIPTION 🎀

This module gives you an interface to the ChaCha stream cipher. That's the whole description, short and iconic. 💅

🔥 METHODS 🔥

Unless noted otherwise, assume $stream is an existing stream object created via new, like this:

my $stream = Crypt::Stream::ChaCha->new($key, $nonce);

✨ new ✨

Make a new stream object, bestie:

my $stream = Crypt::Stream::ChaCha->new($key, $nonce);
#or
my $stream = Crypt::Stream::ChaCha->new($key, $nonce, $counter, $rounds);

# $key     .. [binary string] 32 or 16 bytes
# $nonce   .. [binary string] 8 or 12 bytes
# $counter .. [integer] initial counter value (DEFAULT: 0)
#             for 12-byte nonces the counter must be <= 0xFFFFFFFF
# $rounds  .. [integer] rounds (DEFAULT: 20)

The args are giving:

• $key — [binary string] 32 or 16 bytes
• $nonce — [binary string] 8 or 12 bytes
• $counter — [integer] initial counter value (DEFAULT: 0); for 12-byte nonces the counter must be <= 0xFFFFFFFF
• $rounds — [integer] rounds (DEFAULT: 20)

🔐 crypt 🔐

Encrypts or decrypts data. The output has the same length as the input. Returns a binary string (raw bytes). 💖

The input is converted using Perl's usual scalar stringification. Passing undef is treated as an empty string with the usual warning, and numeric scalars are stringified before processing.

my $ciphertext = $stream->crypt($plaintext);
#or
my $plaintext = $stream->crypt($ciphertext);

🌈 keystream 🌈

Returns $length bytes of raw keystream as a binary string. ⭐

The length is taken using Perl's usual numeric coercion. Values that coerce to an oversized unsigned length are rejected as too large.

my $random_key = $stream->keystream($length);

🦋 clone 🦋

Returns a copy of the stream cipher object in its current state. Main character energy, but for objects 💅

my $stream2 = $stream->clone();

👑 SEE ALSO 👑

• Crypt::Stream::XChaCha, Crypt::Stream::RC4, Crypt::Stream::Sober128, Crypt::Stream::Salsa20, Crypt::Stream::Sosemanuk — the whole friend group 🫶
• <https://www.rfc-editor.org/rfc/rfc7539> — the RFC link, iykyk

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That's the whole page, bestie 💖 this was perl v5.42.0, dated 2026-05-11, and it's the Crypt::...::ChaCha(3) manual page. slay ✨