Crypt::Argon2 - Perl interface to the Argon2 key derivation functions

NAME

Crypt::Argon2 − Perl interface to the Argon2 key derivation functions

use Crypt::Argon2 qw/argon2id_pass argon2_verify/;
sub add_pass {
my ($user, $password) = @_;
my $salt = get_random(16);
my $encoded = argon2id_pass($password, $salt, 3, '32M', 1, 16);
store_password($user, $encoded);
}
sub check_password {
my ($user, $password) = @_;
my $encoded = fetch_encoded($user);
return argon2_verify($encoded, $password);
}

DESCRIPTION

This module implements the Argon2 key derivation function, which is suitable to convert any password into a cryptographic key. This is most often used to for secure storage of passwords but can also be used to derive a encryption key from a password. It offers variable time and memory costs as well as output size.

To find appropriate parameters, the bundled program "argon2−calibrate" can be used.

FUNCTIONS

argon2_pass($type, $password, $salt, $t_cost, $m_factor, $parallelism,$tag_size)

This function processes the $password with the given $salt and parameters. It encodes the resulting tag and the parameters as a password string (e.g. "$argon2id$v=19$m=65536,t=2,p=1$c29tZXNhbHQ$wWKIMhR9lyDFvRz9YTZweHKfbftvj+qf+YFY4NeBbtA").

•

$type

The argon2 type that is used. This must be one of 'argon2id', 'argon2i' or 'argon2d'.

•

$password

This is the password that is to be turned into a cryptographic key.

•

$salt

This is the salt that is used. It must be long enough to be unique.

•

$t_cost

This is the time−cost factor, typically a small integer that can be derived as explained above.

•

$m_factor

This is the memory costs factor. This must be given as a integer followed by an order of magnitude ("k", "M" or "G" for kilobytes, megabytes or gigabytes respectively), e.g. '64M'.

•

$parallelism

This is the number of threads that are used in computing it.

•

$tag_size

This is the size of the raw result in bytes. Typical values are 16 or 32.

argon2_verify($encoded, $password)

This verifies that the $password matches $encoded. All parameters and the tag value are extracted from $encoded, so no further arguments are necessary.

argon2_raw($type, $password, $salt, $t_cost, $m_factor, $parallelism,$tag_size)

This function processes the $password with the given $salt and parameters much like "argon2_pass", but returns the binary tag instead of a formatted string.

argon2id_pass($password, $salt, $t_cost, $m_factor, $parallelism,$tag_size)

argon2i_pass($password, $salt, $t_cost, $m_factor, $parallelism, $tag_size)

argon2d_pass($password, $salt, $t_cost, $m_factor, $parallelism, $tag_size)

This function processes the $password much like "argon2_pass" does, but the $type argument is set like the function name.

argon2id_verify($encoded, $password)

argon2i_verify($encoded, $password)

argon2d_verify($encoded, $password)

This verifies that the $password matches $encoded and the given type. All parameters and the tag value are extracted from $encoded, so no further arguments are necessary.

argon2id_raw($password, $salt, $t_cost, $m_factor, $parallelism, $tag_size)

argon2i_raw($password, $salt, $t_cost, $m_factor, $parallelism, $tag_size)

argon2d_raw($password, $salt, $t_cost, $m_factor, $parallelism, $tag_size)

This function processes the $password much like "argon2_raw" does, but the $type argument is set like the function name.

argon2_needs_rehash($encoded, $type, $t_cost, $m_cost, $parallelism,$output_length, $salt_length)

This function checks if a password−encoded string needs a rehash. It will return true if the $type (valid values are "argon2i", "argon2id" or "argon2d"), $t_cost, $m_cost, $parallelism, $output_length or $salt_length arguments mismatches any of the parameters of the password−encoded hash.

argon2_types

This returns all supported argon2 subtypes. Currently that's 'argon2id', 'argon2i' and 'argon2d'.

ACKNOWLEDGEMENTS

This module is based on the reference implementation as can be found at <https://github.com/P−H−C/phc−winner−argon2>.

AUTHOR

Leon Timmermans <[email protected]>

COPYRIGHT AND LICENSE

This is free software, licensed under:

The Apache License, Version 2.0, January 2004

Updated 2026-06-01 - jenkler.se | uex.se