Crypt::Digest::BLAKE2b_256(3) User Contributed Perl Documentation Crypt::Digest::BLAKE2b_256(3)

Crypt::Digest::BLAKE2b_256 - Hash function BLAKE2b [size: 256 bits]

### Functional interface:
use Crypt::Digest::BLAKE2b_256 qw( blake2b_256 blake2b_256_hex blake2b_256_b64 blake2b_256_b64u
                             blake2b_256_file blake2b_256_file_hex blake2b_256_file_b64 blake2b_256_file_b64u );
# calculate digest from string/buffer
my $data = 'data string';
my $blake2b_256_raw  = blake2b_256($data);
my $blake2b_256_hex  = blake2b_256_hex($data);
my $blake2b_256_b64  = blake2b_256_b64($data);
my $blake2b_256_b64u = blake2b_256_b64u($data);
# or from file
my $blake2b_256_file_raw  = blake2b_256_file('filename.dat');
my $blake2b_256_file_hex  = blake2b_256_file_hex('filename.dat');
my $blake2b_256_file_b64  = blake2b_256_file_b64('filename.dat');
my $blake2b_256_file_b64u = blake2b_256_file_b64u('filename.dat');
# or from filehandle
my $filehandle = ...; # existing binary-mode filehandle
my $blake2b_256_fh_raw  = blake2b_256_file($filehandle);
my $blake2b_256_fh_hex  = blake2b_256_file_hex($filehandle);
my $blake2b_256_fh_b64  = blake2b_256_file_b64($filehandle);
my $blake2b_256_fh_b64u = blake2b_256_file_b64u($filehandle);
### OO interface:
use Crypt::Digest::BLAKE2b_256;
my $d = Crypt::Digest::BLAKE2b_256->new;
$d->add('any data');
my $result_raw  = $d->digest;     # raw bytes
my $result_hex  = $d->hexdigest;  # hexadecimal form
my $result_b64  = $d->b64digest;  # Base64 form
my $result_b64u = $d->b64udigest; # Base64 URL-safe form
# or hash a file instead
my $file_result_raw = Crypt::Digest::BLAKE2b_256->new->addfile('filename.dat')->digest;

Provides an interface to the BLAKE2b_256 digest algorithm.

Nothing is exported by default.

You can export selected functions:

use Crypt::Digest::BLAKE2b_256 qw(blake2b_256 blake2b_256_hex blake2b_256_b64 blake2b_256_b64u
                                    blake2b_256_file blake2b_256_file_hex blake2b_256_file_b64 blake2b_256_file_b64u);

Or all of them at once:

use Crypt::Digest::BLAKE2b_256 ':all';

Joins all arguments into a single string and returns its BLAKE2b_256 digest encoded as a binary string.

Data arguments for the functional helpers are converted to byte strings using Perl's usual scalar stringification. Defined scalars, including numbers and string-overloaded objects, are accepted. "undef" is treated as an empty string and may emit Perl's usual "uninitialized value" warning. The same rules apply to "blake2b_256_hex", "blake2b_256_b64", and "blake2b_256_b64u".

my $blake2b_256_raw = blake2b_256('data string');
#or
my $blake2b_256_raw = blake2b_256('any data', 'more data', 'even more data');

Joins all arguments into a single string and returns its BLAKE2b_256 digest encoded as a hexadecimal string.

my $blake2b_256_hex = blake2b_256_hex('data string');
#or
my $blake2b_256_hex = blake2b_256_hex('any data', 'more data', 'even more data');

Joins all arguments into a single string and returns its BLAKE2b_256 digest encoded as a Base64 string, with trailing '=' padding.

my $blake2b_256_b64 = blake2b_256_b64('data string');
#or
my $blake2b_256_b64 = blake2b_256_b64('any data', 'more data', 'even more data');

Joins all arguments into a single string and returns its BLAKE2b_256 digest encoded as a Base64 URL-safe string (see RFC 4648 section 5).

my $blake2b_256_b64url = blake2b_256_b64u('data string');
#or
my $blake2b_256_b64url = blake2b_256_b64u('any data', 'more data', 'even more data');

Reads a file given by a filename or filehandle and returns its BLAKE2b_256 digest encoded as a binary string.

my $blake2b_256_raw = blake2b_256_file('filename.dat');
#or
my $filehandle = ...; # existing binary-mode filehandle
my $blake2b_256_raw = blake2b_256_file($filehandle);

Reads a file given by a filename or filehandle and returns its BLAKE2b_256 digest encoded as a hexadecimal string.

my $blake2b_256_hex = blake2b_256_file_hex('filename.dat');
#or
my $filehandle = ...; # existing binary-mode filehandle
my $blake2b_256_hex = blake2b_256_file_hex($filehandle);

Note: The filehandle must be in binary mode before you pass it to addfile().

Reads a file given by a filename or filehandle and returns its BLAKE2b_256 digest encoded as a Base64 string, with trailing '=' padding.

my $blake2b_256_b64 = blake2b_256_file_b64('filename.dat');
#or
my $filehandle = ...; # existing binary-mode filehandle
my $blake2b_256_b64 = blake2b_256_file_b64($filehandle);

Reads a file given by a filename or filehandle and returns its BLAKE2b_256 digest encoded as a Base64 URL-safe string (see RFC 4648 section 5).

my $blake2b_256_b64url = blake2b_256_file_b64u('filename.dat');
#or
my $filehandle = ...; # existing binary-mode filehandle
my $blake2b_256_b64url = blake2b_256_file_b64u($filehandle);

The OO interface provides the same set of functions as Crypt::Digest. Unless noted otherwise, assume $d is an existing digest object created via "new", for example:

my $d = Crypt::Digest::BLAKE2b_256->new();

my $d = Crypt::Digest::BLAKE2b_256->new();

$d->clone();

$d->reset();

Appends data to the message. Returns the object itself (for chaining).

Each argument is converted to bytes using Perl's usual scalar stringification. Defined scalars, including numbers and string-overloaded objects, are accepted. "undef" is treated as an empty string and may emit Perl's usual "uninitialized value" warning.

$d->add('any data');
#or
$d->add('any data', 'more data', 'even more data');

Reads the file content and appends it to the message. Returns the object itself (for chaining).

$d->addfile('filename.dat');
#or
my $filehandle = ...; # existing binary-mode filehandle
$d->addfile($filehandle);

$d->hashsize;
#or
Crypt::Digest::BLAKE2b_256->hashsize();
#or
Crypt::Digest::BLAKE2b_256::hashsize();

Returns the binary digest (raw bytes). The first call finalizes the digest object. Any later add(), addfile(), digest(), hexdigest(), b64digest(), or b64udigest() call will fail until you call reset().

my $result_raw = $d->digest();

Returns the digest encoded as a lowercase hexadecimal string. Like digest(), the first call finalizes the digest object.

my $result_hex = $d->hexdigest();

Returns the digest encoded as a Base64 string with trailing "=" padding. Like digest(), the first call finalizes the digest object.

my $result_b64 = $d->b64digest();

Returns the digest encoded as a Base64 URL-safe string (no trailing "="). Like digest(), the first call finalizes the digest object.

my $result_b64url = $d->b64udigest();

2026-05-12 perl v5.42.2