1 files changed, 107 insertions, 0 deletions
diff --git a/lib/Spreadsheet/ParseXLSX/Decryptor/Agile.pm b/lib/Spreadsheet/ParseXLSX/Decryptor/Agile.pm
new file mode 100644
index 0000000..3b836e3
--- /dev/null
+++ b/lib/Spreadsheet/ParseXLSX/Decryptor/Agile.pm
@@ -0,0 +1,107 @@
+package Spreadsheet::ParseXLSX::Decryptor::Agile;
+use strict;
+use warnings;
+
+use base 'Spreadsheet::ParseXLSX::Decryptor';
+
+sub new {
+    my $class = shift;
+    my $self = Spreadsheet::ParseXLSX::Decryptor->new(@_);
+    bless $self, $class;
+}
+
+sub decrypt {
+    my $self = shift;
+    my ($encryptedValue, $blockKey) = @_;
+
+    my $key = $self->_generateDecryptionKey($blockKey);
+    my $iv = $self->_generateInitializationVector('', $self->{blockSize});
+    my $cbc = Crypt::Mode::CBC->new($self->{cipherAlgorithm}, 0);
+    return $cbc->decrypt($encryptedValue, $key, $iv);
+}
+
+sub _generateDecryptionKey {
+    my $self = shift;
+    my ($blockKey) = @_;
+
+    my $hash;
+
+    unless ($self->{pregeneratedKey}) {
+        $hash = $self->{hashProc}->($self->{salt} . Encode::encode('UTF-16LE', $self->{password}));
+        for (my $i = 0; $i < $self->{spinCount}; $i++) {
+            $hash = $self->{hashProc}->(pack('L', $i) . $hash);
+        }
+        $self->{pregeneratedKey} = $hash;
+    }
+
+    $hash = $self->{hashProc}->($self->{pregeneratedKey} . $blockKey);
+
+    if (length($hash) > $self->{keyLength}) {
+        $hash = substr($hash, 0, $self->{keyLength});
+    } elsif (length($hash) < $self->{keyLength}) {
+        $hash .= "\x36" x ($self->{keyLength} - length($hash));
+    }
+    return $hash;
+}
+
+sub _generateInitializationVector {
+    my $self = shift;
+    my ($blockKey, $blockSize) = @_;
+
+    my $iv;
+    if ($blockKey) {
+        $iv = $self->{hashProc}->($self->{salt} . $blockKey);
+    } else {
+        $iv = $self->{salt};
+    }
+
+    if (length($iv) > $blockSize) {
+        $iv = substr($iv, 0, $blockSize);
+    } elsif (length($iv) < $blockSize) {
+        $iv = $iv . ("\x36" x ($blockSize - length($iv)));
+    }
+
+    return $iv;
+}
+
+sub decryptFile {
+    my $self = shift;
+    my ($inFile, $outFile, $bufferLength, $key, $fileSize) = @_;
+
+    my $cbc = Crypt::Mode::CBC->new($self->{cipherAlgorithm}, 0);
+
+    my $inbuf;
+    my $i = 0;
+
+    while (($fileSize > 0) && (my $inlen = $inFile->read($inbuf, $bufferLength))) {
+        my $blockId = pack('L', $i);
+
+        my $iv = $self->_generateInitializationVector($blockId, $self->{blockSize});
+
+        if ($inlen < $bufferLength) {
+            $inbuf .= "\x00" x ($bufferLength - $inlen);
+        }
+
+        my $outbuf = $cbc->decrypt($inbuf, $key, $iv);
+        if ($fileSize < $inlen) {
+            $inlen = $fileSize;
+        }
+
+        $outFile->write($outbuf, $inlen);
+        $i++;
+        $fileSize -= $inlen;
+    }
+}
+
+sub verifyPassword {
+    my $self = shift;
+
+    my ($encryptedVerifier, $encryptedVerifierHash) = @_;
+
+    my $encryptedVerifierHash0 = $self->{hashProc}->($self->decrypt($encryptedVerifier, "\xfe\xa7\xd2\x76\x3b\x4b\x9e\x79"));
+    $encryptedVerifierHash = $self->decrypt($encryptedVerifierHash, "\xd7\xaa\x0f\x6d\x30\x61\x34\x4e");
+
+    die "Wrong password: $self" unless ($encryptedVerifierHash0 eq $encryptedVerifierHash);
+}
+
+1;