Crypt::...Blowfish(3)

🌸 NAME 🌸

Crypt::Cipher::Blowfish — Symmetric cipher Blowfish, key size: 64-576 bits.

Bestie, welcome to the manual page for Crypt::...Blowfish(3), straight from the User Contributed Perl Documentation. It's lowkey iconic and we're gonna read it together, no cap. 💖

✨ SYNOPSIS ✨

Two ways to slide into this cipher, bestie — one with Crypt::Mode::CBC, one with Crypt::CBC (labeled slower). Copy these examples exactly, character for character, okay? 🫶

### example 1
use Crypt::Mode::CBC;

my $key = '...'; # length must be a valid key size for this cipher
my $iv = '...';  # 16 bytes
my $cbc = Crypt::Mode::CBC->new('Blowfish');
my $ciphertext = $cbc->encrypt("secret data", $key, $iv);

### example 2 (slower)
use Crypt::CBC;
use Crypt::Cipher::Blowfish;

my $key = '...'; # length must be a valid key size for this cipher
my $iv = '...';  # 16 bytes
my $cbc = Crypt::CBC->new( -cipher=>'Cipher::Blowfish', -key=>$key, -iv=>$iv );
my $ciphertext = $cbc->encrypt("secret data");

🦋 DESCRIPTION 🦋

This module implements the Blowfish cipher. Its interface is compatible with Crypt::CBC.

💀 Note: This module only implements single-block encryption and decryption. For general data, use a block mode such as Crypt::Mode::CBC, Crypt::Mode::CTR, or Crypt::CBC (and yes, Crypt::CBC is the slower one).

👑 METHODS 👑

Unless noted otherwise, assume $c is an existing cipher object created via new, for example:

my $c = Crypt::Cipher::Blowfish->new($key);

Now the methods, periodt. 💅

🌟 new 🌟

Make a cipher object, bestie. You can pass just $key, or $key plus $rounds:

my $c = Crypt::Cipher::Blowfish->new($key);
#or
my $c = Crypt::Cipher::Blowfish->new($key, $rounds);

# $key .... [binary string] key of an accepted length (see keysize, min_keysize, max_keysize)
# $rounds . [integer] optional, number of rounds (if supported by the cipher; croaks on invalid value)

The tea ☕: $key is a [binary string] key of an accepted length (peep keysize, min_keysize, max_keysize), and $rounds is an optional [integer] number of rounds — if supported by the cipher — and it croaks on invalid value.

🔥 encrypt 🔥

Encrypts exactly one block of plaintext. The length of $plaintext must equal blocksize; croaks otherwise. An empty string is accepted and returned unchanged.

my $ciphertext = $c->encrypt($plaintext);

Returns the encrypted block as a binary string (raw bytes).

💜 decrypt 💜

Decrypts exactly one block of ciphertext. The length of $ciphertext must equal blocksize; croaks otherwise. An empty string is accepted and returned unchanged.

my $plaintext = $c->decrypt($ciphertext);

Returns the decrypted block as a binary string (raw bytes).

🎀 keysize 🎀

Just an alias for max_keysize, simple as that.

$c->keysize;
#or
Crypt::Cipher::Blowfish->keysize;
#or
Crypt::Cipher::Blowfish::keysize;

🧚 blocksize 🧚

Returns the cipher block size (in bytes).

$c->blocksize;
#or
Crypt::Cipher::Blowfish->blocksize;
#or
Crypt::Cipher::Blowfish::blocksize;

⭐ max_keysize ⭐

Returns the maximum key size (in bytes).

$c->max_keysize;
#or
Crypt::Cipher::Blowfish->max_keysize;
#or
Crypt::Cipher::Blowfish::max_keysize;

🌈 min_keysize 🌈

Returns the minimum key size (in bytes).

$c->min_keysize;
#or
Crypt::Cipher::Blowfish->min_keysize;
#or
Crypt::Cipher::Blowfish::min_keysize;

🍓 default_rounds 🍓

Returns the cipher's default round count.

$c->default_rounds;
#or
Crypt::Cipher::Blowfish->default_rounds;
#or
Crypt::Cipher::Blowfish::default_rounds;

💅 SEE ALSO 💅

Related besties:

• CryptX, Crypt::Cipher
• <https://en.wikipedia.org/wiki/Blowfish_(cipher)>

💖 That's the whole page, bestie! Source/version: perl v5.42.0; date: 2026-05-11; manual page: Crypt::...Blowfish(3). Mwah! 💋✨