encrypt and decrypt

aes.pl

#!/usr/bin/env perl

# $ perl aes.pl decrypt $(perl aes.pl encrypt 123 qaz)  # 123 is the key and qaz is the plaintext
# qaz                                                   # qaz is the plaintext from the 123 ciphertext encryption

# $ key=123 ciphertext=08eaad9aec6b6ccba1067aa4de838dd3d5c6423024d5eb087a4e70cd32b9caba
# $ perl aes.pl decrypt $key $ciphertext
# qaz
# $ perl aes.pl decrypt 40bd001563085fc35165329ea1ff5c5ecbdbbeef40bd001563085fc35165329e $ciphertext
# qaz                                                  # 40b...29e is the actual key derived from 123 and used in the enc/dec
#                                                      # this allows a simple key of any length or a randomly generated complex key

# Now quickly share the ciphertext!
# $ key=123 plaintext=qaz
# $ perl aes.pl e $key $plaintext | curl -F 'f:1=<-' ix.io
# 123 / 40bd001563085fc35165329ea1ff5c5ecbdbbeef40bd001563085fc35165329e   # the key printed to STDERR
# http://ix.io/4DUQ                                                        # the URL the ciphertext was posted to
# $ perl aes.pl d $key $(curl -s http://ix.io/4DUQ)                        # the key and the URL the cipertext was posted to
# qaz                                                                      # the decrypted plaintext!
# $ curl -s http://ix.io/4DUS                                              # see, it's just the ciphertext!
# 30e7f01c5b09cc8be9fd5a818e90e33de547b8f5661f3137974762cf54680734
# $ perl aes.pl d $key 30e7f01c5b09cc8be9fd5a818e90e33de547b8f5661f3137974762cf54680734
# qaz                                                                      # and as expected, the decrypted plaintext!

use 5.010;
use Crypt::CBC qw();
use Digest::SHA qw(sha1_hex);

my %cipher_options = (-cipher => 'Rijndael', -literal_key => 1, -header => 'none', -pbkdf =>'pbkdf2');

sub encrypt {
  my $iv = Crypt::CBC->random_bytes(16);
  my $cipher = Crypt::CBC->new(%cipher_options, -key => $_[0], -iv => $iv);
  return $iv.$cipher->encrypt($_[1]);
}

sub decrypt {
  my $iv = substr($_[1], 0, 16, '');
  my $cipher = Crypt::CBC->new(%cipher_options, -key => $_[0], -iv => $iv);
  return $cipher->decrypt($_[1]);
}

my $mode = shift @ARGV;
if (substr($mode, 0, 1) eq 'e') {
  my $key = $ARGV[0] ? substr(sha1_hex($ARGV[0]) x 2, 0, 64) : unpack('H*', Crypt::CBC->random_bytes(32));
  printf STDERR "%s\n", $ARGV[0] ? "$ARGV[0] / $key" : $key;
  printf "%s %s\n", ($ARGV[0] || $key), unpack("H*", encrypt(pack('H*', $key), join "\n", $ARGV[1] || <STDIN>));
}
elsif (substr($mode, 0, 1) eq 'd') {
  my $key = $ARGV[0] =~ /^[0-9a-f]{64}$/ ? $ARGV[0] : substr(sha1_hex($ARGV[0]) x 2, 0, 64);
  chomp(my $ciphertext = $ARGV[1] || <STDIN>);
  printf "%s", decrypt(pack("H*", $key), pack("H*", $ciphertext));
}