Crypt::OpenPGP::MDC - MDC (modification detection code) packet
use Crypt::OpenPGP::MDC;
my $mdc = Crypt::OpenPGP::MDC->new( Data => 'foobar' );
my $digest = $mdc->digest;
my $serialized = $mdc->save;
my $mdc = Crypt::OpenPGP::MDC->parse($buffer);
my $digest = $mdc->digest;
Crypt::OpenPGP::MDC is a PGP MDC (modification detection code) packet.
Such a packet is used alongside Encrypted-MDC data packets so that
modifications to the ciphertext can be detected. The MDC packet contains
a SHA-1 digest of the plaintext for comparison with the decrypted
plaintext.
You generally will never need to construct a Crypt::OpenPGP::MDC packet yourself; usage is by the Crypt::OpenPGP::Ciphertext object.
Creates a new MDC packet object and returns that object. If you do not supply any data $data, the object is created empty; this is used, for example, in parse (below), to create an empty packet which is then filled from the data in the buffer.
If you wish to initialize a non-empty object, supply new with
the Data parameter along with a value $data. $data should
contain the plaintext prefix (length = cipher blocksize + 2), the actual
plaintext, and two octets corresponding to the hex digits 0xd3 and
0x14.
Returns the text of the MDC packet; this is the digest of the data passed to new (above) as $data, for example.
Given $buffer, a Crypt::OpenPGP::Buffer object holding (or with offset pointing to) an MDC packet, returns a new <Crypt::OpenPGP::MDC> object, initialized with the MDC data in the buffer.
Returns the MDC digest data (eg. the string passed as $data to new, above).
Please see the Crypt::OpenPGP manpage for author, copyright, and license information.