Add AACS media key block models

BurnOutSharp.Models/AACS/EndOfMediaKeyBlockRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// A properly formatted MKB shall contain an End of Media Key Block Record.
+    /// When a device encounters this Record it stops processing the MKB, using
+    /// whatever Km value it has calculated up to that point as the final Km for
+    /// that MKB (pending possible checks for correctness of the key, as
+    /// described previously).
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class EndOfMediaKeyBlockRecord : Record
+    {
+        /// <summary>
+        /// AACS LA’s signature on the data in the Media Key Block up to,
+        /// but not including, this record. Devices depending on the Version
+        /// Number in the Type and Version Record must verify the signature.
+        /// Other devices may ignore the signature data. If any device
+        /// determines that the signature does not verify or is omitted, it
+        /// must refuse to use the Media Key.
+        /// </summary>
+        public byte[] SignatureData;
+    }
+}

BurnOutSharp.Models/AACS/Enums.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    public enum RecordType : byte
+    {
+        EndOfMediaKeyBlock = 0x02,
+        ExplicitSubsetDifference = 0x04,
+        MediaKeyData = 0x05,
+        SubsetDifferenceIndex = 0x07,
+        TypeAndVersion = 0x10,
+        VerifyMediaKey = 0x81,
+    }
+}

BurnOutSharp.Models/AACS/ExplicitSubsetDifferenceRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class ExplicitSubsetDifferenceRecord : Record
+    {
+        /// <summary>
+        /// In this record, each subset-difference is encoded with 5 bytes.
+        /// </summary>
+        public SubsetDifference[] SubsetDifferences;
+    }
+}

BurnOutSharp.Models/AACS/MediaKeyBlock.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// A Media Key Block is formatted as a sequence of contiguous Records.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class MediaKeyBlock
+    {
+        /// <summary>
+        /// Records
+        /// </summary>
+        public Record[] Records { get; set; }
+    }
+}

BurnOutSharp.Models/AACS/MediaKeyDataRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// This record gives the associated encrypted media key data for the
+    /// subset-differences identified in the Explicit Subset-Difference Record.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class MediaKeyDataRecord : Record
+    {
+        /// <summary>
+        /// Each subset difference has its associated 16 bytes in this
+        /// record, in the same order it is encountered in the subset-difference
+        /// record. This 16 bytes is the ciphertext value C in the media
+        /// key calculation.
+        /// </summary>
+        public byte[][] MediaKeyData;
+    }
+}

BurnOutSharp.Models/AACS/Record.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// Each Record begins with a one-byte Record Type field, followed by a
+    /// three-byte Record Length field. 
+    /// 
+    /// The following subsections describe the currently defined Record types,
+    /// and how a device processes each. All multi-byte integers, including
+    /// the length field, are “Big Endian”; in other words, the most significant
+    /// byte comes first in the record.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public abstract class Record
+    {
+        /// <summary>
+        /// The Record Type field value indicates the type of the Record.
+        /// </summary>
+        public RecordType RecordType;
+
+        /// <summary>
+        /// The Record Length field value indicates the number of bytes in
+        /// the Record, including the Record Type and the Record Length
+        /// fields themselves. Record lengths are always multiples of 4 bytes.
+        /// </summary>
+        // <remarks>UInt24 not UInt32</remarks>
+        public uint RecordLength;
+    }
+}

BurnOutSharp.Models/AACS/SubsetDifference.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class SubsetDifference
+    {
+        /// <summary>
+        /// The mask for u is given by the first byte. That byte is
+        /// treated as a number, the number of low-order 0-bits in
+        /// the mask. For example, the value 0x01 denotes a mask of
+        /// 0xFFFFFFFE; value 0x0A denotes a mask of 0xFFFFFC00.
+        /// </summary>
+        public byte Mask;
+
+        /// <summary>
+        /// The last 4 bytes are the uv number, most significant
+        /// byte first.
+        /// </summary>
+        public uint Number;
+    }
+}

BurnOutSharp.Models/AACS/SubsetDifferenceIndexRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// This is a speed-up record which can be ignored by devices not wishing to
+    /// take advantage of it. It is a lookup table which allows devices to quickly
+    /// find their subset-difference in the Explicit Subset-Difference record,
+    /// without processing the entire record. This Subset-Difference Index record
+    /// is always present, and always precedes the Explicit Subset-Difference record
+    /// in the MKB, although it does not necessarily immediately precede it.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class SubsetDifferenceIndexRecord : Record
+    {
+        /// <summary>
+        /// The number of devices per index offset.
+        /// </summary>
+        public uint Span;
+
+        /// <summary>
+        /// These offsets refer to the offset within the following Explicit
+        /// Subset-Difference record, with 0 being the start of the record.
+        /// </summary>
+        // <remarks>UInt24 not UInt32</remarks>
+        public uint[] Offsets;
+    }
+}

BurnOutSharp.Models/AACS/TypeAndVersionRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// Devices, except for recording devices which are writing Media Key Block
+    /// Extensions, may ignore this record. Recording devices shall verify the
+    /// signature (see End of Media Key Block record) and use the Version Number
+    /// in this record to determine if a new Media Key BLock Extension is, in
+    /// fact, more recent than the Media Key Block Extension that is currently
+    /// on the media.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class TypeAndVersionRecord : Record
+    {
+        /// <summary>
+        /// For AACS applications, the type field is always 0x00031003.
+        /// Devices shall ignore this.
+        /// </summary>
+        public uint MKBType;
+
+        /// <summary>
+        /// The Version Number is a 32-bit unsigned integer. Each time the
+        /// licensing agency changes the revocation, it increments the version
+        /// number and inserts the new value in subsequent Media Key Blocks.
+        /// Thus, larger values indicate more recent Media Key Blocks. The
+        /// Version Numbers begin at 1; 0 is a special value used for test
+        /// Media Key Blocks.
+        /// </summary>
+        public uint VersionNumber;
+    }
+}

BurnOutSharp.Models/AACS/VerifyMediaKeyRecord.cs

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+namespace BurnOutSharp.Models.AACS
+{
+    /// <summary>
+    /// A properly formatted MKB shall have exactly one Verify Media Key Record
+    /// as its first record. The presence of the Verify Media Key Record in an MKB
+    /// is mandatory, but the use of the Record by a device is not mandatory. The
+    /// device may use the Verify Media Key Record to verify the correctness of a
+    /// given MKB, or of its processing of it. If everything is correct, the device
+    /// should observe the condition:
+    ///     [AES_128D(vKm, C]msb_64 == 0x0123456789ABCDEF)]
+    /// where Km is the Media Key value.
+    /// </summary>
+    /// <see href="http://web.archive.org/web/20180718234519/https://aacsla.com/jp/marketplace/evaluating/aacs_technical_overview_040721.pdf"/>
+    public sealed class VerifyMediaKeyRecord : Record
+    {
+        /// <summary>
+        /// Bytes 4 through 19 of the Record contain the ciphertext value
+        ///     Cv = AES-128E (Km, 0x0123456789ABCDEF || 0xXXXXXXXXXXXXXXXX)
+        /// where 0xXXXXXXXXXXXXXXXX is an arbitrary 8-byte value, and Km is
+        /// the correct final Media Key value.
+        /// </summary>
+        public byte[] CiphertextValue;
+    }
+}