public byte [] DownloadSong(Hashtable song, Progress ProgressCallback)
{
int i;
Rijndael alg;
string strDownloadKey = (string)song["downloadKey"];
if (strDownloadKey == null)
{
throw new Exception("Can't download song without downloadKey");
}
byte [] encData = Request((string)song["URL"], null, null,
"downloadKey=" + strDownloadKey,
null, ProgressCallback);
alg = Rijndael.Create();
alg.Mode = CipherMode.CBC;
alg.Padding = PaddingMode.None;
MemoryStream cms = new MemoryStream();
byte [] ftyp = Encoding.ASCII.GetBytes("\0\0\0\0ftypM4A \0\0\0\0");
cms.Write(ftyp, 0, ftyp.Length);
byte [] Key = HexStringToBytes((string)song["encryptionKey"]);
byte [] IV = new byte[16];
Buffer.BlockCopy(encData, 0, IV, 0, 16);
ICryptoTransform ct = alg.CreateDecryptor(Key, IV);
CryptoStream cs =
new CryptoStream(cms, ct, CryptoStreamMode.Write);
cs.Write(encData, 16, ((encData.Length - 16) / 16) * 16);
cs.Close();
byte [] mp4 = cms.ToArray();
byte [] moov = Encoding.ASCII.GetBytes("moov");
for (i = 0; i < mp4.Length - 4; i++)
{
if (mp4[i + 0] == moov[0] && mp4[i + 1] == moov[1] &&
mp4[i + 2] == moov[2] && mp4[i + 3] == moov[3])
{
byte [] offb = BitConverter.GetBytes((UInt32)(i - 4));
if (BitConverter.IsLittleEndian)
{
Array.Reverse(offb, 0, 4);
}
Buffer.BlockCopy(offb, 0, mp4, 0, offb.Length);
break;
}
}
MP4Root root = new MP4Root();
try
{
root.Parse(new MemoryStream(mp4));
}
catch (InvalidBoxSizeException e)
{
}
MP4Box mp4a = root[MP4Types.MP4A];
if (mp4a != null)
{
MP4Box sinf = mp4a[MP4Types.SINF];
if (sinf != null)
{
mp4a.Size -= sinf.Size;
sinf.Free();
}
}
return(root.Bytes);
}
public byte[] DownloadSong( Hashtable song, Progress ProgressCallback )
{
int i;
Rijndael alg;
string strDownloadKey = (string)song[ "downloadKey" ];
if( strDownloadKey == null )
{
throw new Exception( "Can't download song without downloadKey" );
}
byte [] encData = Request( (string)song[ "URL" ], null, null,
"downloadKey=" + strDownloadKey,
null, ProgressCallback );
alg = Rijndael.Create();
alg.Mode = CipherMode.CBC;
alg.Padding = PaddingMode.None;
MemoryStream cms = new MemoryStream();
byte [] ftyp = Encoding.ASCII.GetBytes( "\0\0\0\0ftypM4A \0\0\0\0" );
cms.Write( ftyp, 0, ftyp.Length );
byte [] Key = HexStringToBytes( (string)song[ "encryptionKey" ] );
byte [] IV = new byte[ 16 ];
Buffer.BlockCopy( encData, 0, IV, 0, 16 );
ICryptoTransform ct = alg.CreateDecryptor( Key, IV );
CryptoStream cs =
new CryptoStream( cms, ct, CryptoStreamMode.Write );
cs.Write( encData, 16, ((encData.Length - 16) / 16) * 16 );
cs.Close();
byte [] mp4 = cms.ToArray();
byte [] moov = Encoding.ASCII.GetBytes( "moov" );
for( i = 0; i < mp4.Length - 4; i++ )
{
if( mp4[ i + 0 ] == moov[ 0 ] && mp4[ i + 1 ] == moov[ 1 ] &&
mp4[ i + 2 ] == moov[ 2 ] && mp4[ i + 3 ] == moov[ 3 ] )
{
byte [] offb = BitConverter.GetBytes( (UInt32)(i - 4) );
if( BitConverter.IsLittleEndian )
Array.Reverse( offb, 0, 4 );
Buffer.BlockCopy( offb, 0, mp4, 0, offb.Length );
break;
}
}
MP4Root root = new MP4Root();
try
{
root.Parse( new MemoryStream( mp4 ) );
}
catch( InvalidBoxSizeException e )
{
}
MP4Box mp4a = root[ MP4Types.MP4A ];
if( mp4a != null )
{
MP4Box sinf = mp4a[ MP4Types.SINF ];
if( sinf != null )
{
mp4a.Size -= sinf.Size;
sinf.Free();
}
}
return root.Bytes;
}
