9a07ed53eb
Now that we have most of core free of shadowing, we can enable the warning as an error to catch anything that may be remaining and also eliminate this class of logic bug entirely.
54 lines
1.8 KiB
C++
54 lines
1.8 KiB
C++
// Copyright 2018 yuzu emulator team
|
|
// Licensed under GPLv2 or any later version
|
|
// Refer to the license.txt file included.
|
|
|
|
#include <algorithm>
|
|
#include <cstring>
|
|
#include "common/assert.h"
|
|
#include "core/crypto/ctr_encryption_layer.h"
|
|
|
|
namespace Core::Crypto {
|
|
|
|
CTREncryptionLayer::CTREncryptionLayer(FileSys::VirtualFile base_, Key128 key_,
|
|
std::size_t base_offset_)
|
|
: EncryptionLayer(std::move(base_)), base_offset(base_offset_), cipher(key_, Mode::CTR) {}
|
|
|
|
std::size_t CTREncryptionLayer::Read(u8* data, std::size_t length, std::size_t offset) const {
|
|
if (length == 0)
|
|
return 0;
|
|
|
|
const auto sector_offset = offset & 0xF;
|
|
if (sector_offset == 0) {
|
|
UpdateIV(base_offset + offset);
|
|
std::vector<u8> raw = base->ReadBytes(length, offset);
|
|
cipher.Transcode(raw.data(), raw.size(), data, Op::Decrypt);
|
|
return length;
|
|
}
|
|
|
|
// offset does not fall on block boundary (0x10)
|
|
std::vector<u8> block = base->ReadBytes(0x10, offset - sector_offset);
|
|
UpdateIV(base_offset + offset - sector_offset);
|
|
cipher.Transcode(block.data(), block.size(), block.data(), Op::Decrypt);
|
|
std::size_t read = 0x10 - sector_offset;
|
|
|
|
if (length + sector_offset < 0x10) {
|
|
std::memcpy(data, block.data() + sector_offset, std::min<u64>(length, read));
|
|
return std::min<u64>(length, read);
|
|
}
|
|
std::memcpy(data, block.data() + sector_offset, read);
|
|
return read + Read(data + read, length - read, offset + read);
|
|
}
|
|
|
|
void CTREncryptionLayer::SetIV(const IVData& iv_) {
|
|
iv = iv_;
|
|
}
|
|
|
|
void CTREncryptionLayer::UpdateIV(std::size_t offset) const {
|
|
offset >>= 4;
|
|
for (std::size_t i = 0; i < 8; ++i) {
|
|
iv[16 - i - 1] = offset & 0xFF;
|
|
offset >>= 8;
|
|
}
|
|
cipher.SetIV(iv);
|
|
}
|
|
} // namespace Core::Crypto
|