ctr_encryption_layer: Fix bug when transcoding small data

Fixes a bug where data lengths of less than size 0x10 will fail or have misleading return values.
This commit is contained in:
Zach Hilman 2018-08-16 16:58:49 -04:00
parent a9dc5a3c10
commit 6dd369ab88

View file

@ -20,10 +20,8 @@ size_t CTREncryptionLayer::Read(u8* data, size_t length, size_t offset) const {
if (sector_offset == 0) {
UpdateIV(base_offset + offset);
std::vector<u8> raw = base->ReadBytes(length, offset);
if (raw.size() != length)
return Read(data, raw.size(), offset);
cipher.Transcode(raw.data(), length, data, Op::Decrypt);
return length;
cipher.Transcode(raw.data(), raw.size(), data, Op::Decrypt);
return raw.size();
}
// offset does not fall on block boundary (0x10)
@ -34,7 +32,7 @@ size_t CTREncryptionLayer::Read(u8* data, size_t length, size_t offset) const {
if (length + sector_offset < 0x10) {
std::memcpy(data, block.data() + sector_offset, std::min<u64>(length, read));
return read;
return std::min<u64>(length, read);
}
std::memcpy(data, block.data() + sector_offset, read);
return read + Read(data + read, length - read, offset + read);