public NcaFsHeader(BinaryReader reader)
{
long start = reader.BaseStream.Position;
Version = reader.ReadInt16();
FormatType = (NcaFormatType)reader.ReadByte();
HashType = (NcaHashType)reader.ReadByte();
EncryptionType = (NcaEncryptionType)reader.ReadByte();
reader.BaseStream.Position += 3;
switch (HashType)
{
case NcaHashType.Sha256:
Sha256Info = new Sha256Info(reader);
break;
case NcaHashType.Ivfc:
IvfcInfo = new IvfcHeader(reader);
break;
}
if (EncryptionType == NcaEncryptionType.AesCtrEx)
{
BktrInfo = new BktrPatchInfo();
reader.BaseStream.Position = start + 0x100;
BktrInfo.RelocationHeader = new BktrHeader(reader);
BktrInfo.EncryptionHeader = new BktrHeader(reader);
}
if (FormatType == NcaFormatType.Pfs0)
{
Type = SectionType.Pfs0;
}
else if (FormatType == NcaFormatType.Romfs)
{
if (EncryptionType == NcaEncryptionType.AesCtrEx)
{
Type = SectionType.Bktr;
}
else
{
Type = SectionType.Romfs;
}
}
reader.BaseStream.Position = start + 0x140;
Ctr = reader.ReadBytes(8).Reverse().ToArray();
reader.BaseStream.Position = start + 512;
}
public BktrCryptoStream(Stream baseStream, byte[] key, long offset, long length, long counterOffset, byte[] ctrHi, BktrPatchInfo bktr)
: base(baseStream, key, offset, length, counterOffset, ctrHi)
{
BktrHeader header = bktr.EncryptionHeader;
byte[] subsectionBytes;
using (var streamDec = new RandomAccessSectorStream(new Aes128CtrStream(baseStream, key, offset, length, counterOffset, ctrHi)))
{
streamDec.Position = header.Offset;
subsectionBytes = new byte[header.Size];
streamDec.Read(subsectionBytes, 0, subsectionBytes.Length);
}
using (var reader = new BinaryReader(new MemoryStream(subsectionBytes)))
{
AesSubsectionBlock = new AesSubsectionBlock(reader);
}
foreach (AesSubsectionBucket bucket in AesSubsectionBlock.Buckets)
{
SubsectionEntries.AddRange(bucket.Entries);
}
// Add a subsection for the BKTR headers to make things easier
var headerSubsection = new AesSubsectionEntry
{
Offset = bktr.RelocationHeader.Offset,
Counter = (uint)(ctrHi[4] << 24 | ctrHi[5] << 16 | ctrHi[6] << 8 | ctrHi[7]),
OffsetEnd = long.MaxValue
};
SubsectionEntries.Add(headerSubsection);
for (int i = 0; i < SubsectionEntries.Count - 1; i++)
{
SubsectionEntries[i].Next = SubsectionEntries[i + 1];
SubsectionEntries[i].OffsetEnd = SubsectionEntries[i + 1].Offset;
}
SubsectionOffsets = SubsectionEntries.Select(x => x.Offset).ToList();
CurrentEntry = GetSubsectionEntry(0);
UpdateCounterSubsection(CurrentEntry.Counter);
baseStream.Position = offset;
}
