private IStorage OpenAesCtrExStorage(IStorage baseStorage, int index)
{
NcaFsHeader fsHeader = Header.GetFsHeader(index);
NcaFsPatchInfo info = fsHeader.GetPatchInfo();
long sectionOffset = Header.GetSectionStartOffset(index);
long sectionSize = Header.GetSectionSize(index);
long bktrOffset = info.RelocationTreeOffset;
long bktrSize = sectionSize - bktrOffset;
long dataSize = info.RelocationTreeOffset;
byte[] key = GetContentKey(NcaKeyType.AesCtr);
byte[] counter = Aes128CtrStorage.CreateCounter(fsHeader.Counter, bktrOffset + sectionOffset);
byte[] counterEx = Aes128CtrStorage.CreateCounter(fsHeader.Counter, sectionOffset);
IStorage bucketTreeData = new CachedStorage(new Aes128CtrStorage(baseStorage.Slice(bktrOffset, bktrSize), key, counter, true), 4, true);
IStorage encryptionBucketTreeData = bucketTreeData.Slice(info.EncryptionTreeOffset - bktrOffset);
IStorage decStorage = new Aes128CtrExStorage(baseStorage.Slice(0, dataSize), encryptionBucketTreeData, key, counterEx, true);
decStorage = new CachedStorage(decStorage, 0x4000, 4, true);
return(new ConcatenationStorage(new[] { decStorage, bucketTreeData }, true));
}
private IStorage OpenAesCtrExStorage(IStorage baseStorage, int index, bool decrypting)
{
NcaFsHeader fsHeader = GetFsHeader(index);
NcaFsPatchInfo info = fsHeader.GetPatchInfo();
long sectionOffset = Header.GetSectionStartOffset(index);
long sectionSize = Header.GetSectionSize(index);
long bktrOffset = info.RelocationTreeOffset;
long bktrSize = sectionSize - bktrOffset;
long dataSize = info.RelocationTreeOffset;
byte[] key = GetContentKey(NcaKeyType.AesCtr);
byte[] counter = Aes128CtrStorage.CreateCounter(fsHeader.Counter, bktrOffset + sectionOffset);
byte[] counterEx = Aes128CtrStorage.CreateCounter(fsHeader.Counter, sectionOffset);
IStorage bucketTreeData;
IStorage outputBucketTreeData;
if (decrypting)
{
bucketTreeData = new CachedStorage(new Aes128CtrStorage(baseStorage.Slice(bktrOffset, bktrSize), key, counter, true), 4, true);
outputBucketTreeData = bucketTreeData;
}
else
{
bucketTreeData = baseStorage.Slice(bktrOffset, bktrSize);
outputBucketTreeData = new CachedStorage(new Aes128CtrStorage(baseStorage.Slice(bktrOffset, bktrSize), key, counter, true), 4, true);
}
var encryptionBucketTreeData = new SubStorage(bucketTreeData,
info.EncryptionTreeOffset - bktrOffset, sectionSize - info.EncryptionTreeOffset);
var cachedBucketTreeData = new CachedStorage(encryptionBucketTreeData, IndirectStorage.NodeSize, 6, true);
var treeHeader = new BucketTree.Header();
info.EncryptionTreeHeader.CopyTo(SpanHelpers.AsByteSpan(ref treeHeader));
long nodeStorageSize = IndirectStorage.QueryNodeStorageSize(treeHeader.EntryCount);
long entryStorageSize = IndirectStorage.QueryEntryStorageSize(treeHeader.EntryCount);
var tableNodeStorage = new SubStorage(cachedBucketTreeData, 0, nodeStorageSize);
var tableEntryStorage = new SubStorage(cachedBucketTreeData, nodeStorageSize, entryStorageSize);
IStorage decStorage = new Aes128CtrExStorage(baseStorage.Slice(0, dataSize), tableNodeStorage,
tableEntryStorage, treeHeader.EntryCount, key, counterEx, true);
return(new ConcatenationStorage(new[] { decStorage, outputBucketTreeData }, true));
}
