NAME

Crypt::SSSS - implementation of Shamir's Secret Sharing System.

SYNOPSIS

use Crypt::SSSS;

# use (3, 3) scheme
my $shares = ssss_distribute(
    message => "\x06\x1c\x08",
    k       => 3,
);

# Save shares
for my $share (1 .. 3) {
    open my $fh, '>', "share${share}.dat";
    print $fh $shares->{$share}->binary;
    close $fh;
}

# Reconstruct message
my $ishares = {};
for my $share (1 .. 3) {
    open my $fh, '<', "share${share}.dat";
    $ishares->{$share} = do {
        local $/;    # slurp!
        <$fh>;
    };
    close $fh;
}

print "Original message: ", sprintf '"\x%02x\x%02x\x%02x"',
  unpack('C*', ssss_reconstruct(p => 257, shares => $ishares));

DESCRIPTION

Implementation of Shamir's Secret Sharing Scheme.

ATTRIBUTES

Crypt::SSSS implements the following attributes.

ssss_distribute

my $shares = ssss_distribute(
    message => $message,
    k       => $k,
    p       => $p,         # 257 by default
    n       => $n,         # By default equals to k
);

Distribute $message to $n shares, so that any $k shares would be enough to reconstruct the secret. $p is a prime number.

Returns hashref of Crypt::SSSS::Message.

ssss_reconstruct

my $secret = ssss_reconstruct(
    shares => $shares,
    p      => $p,        # 257 by default
);

Reconstruct message from given $shares. $p is a prime number used to distribute message.

AUTHOR

Sergey Zasenko, undef@cpan.org.

COPYRIGHT AND LICENSE

Copyright (C) 2011, 2016, Sergey Zasenko.

This program is free software, you can redistribute it and/or modify it under the same terms as Perl 5.10.