dolphin/Source/Core/DiscIO/VolumeWii.cpp
JosJuice 5f8935932d Blob: Add interface for reading decrypted Wii data directly
This is useful for blob types that store Wii data unencrypted
(such as WIA and discs extracted to directories) so that
we don't have to waste CPU time encrypting in the blob code
just to decrypt right afterwards in the volume code.
2017-08-01 11:36:40 +02:00

422 lines
13 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include "DiscIO/VolumeWii.h"
#include <algorithm>
#include <array>
#include <cstddef>
#include <cstring>
#include <map>
#include <mbedtls/aes.h>
#include <mbedtls/sha1.h>
#include <memory>
#include <optional>
#include <string>
#include <utility>
#include <vector>
#include "Common/Assert.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "Common/MsgHandler.h"
#include "Common/Swap.h"
#include "DiscIO/Blob.h"
#include "DiscIO/DiscExtractor.h"
#include "DiscIO/Enums.h"
#include "DiscIO/Filesystem.h"
#include "DiscIO/Volume.h"
namespace DiscIO
{
constexpr u64 PARTITION_DATA_OFFSET = 0x20000;
VolumeWii::VolumeWii(std::unique_ptr<BlobReader> reader)
: m_pReader(std::move(reader)), m_game_partition(PARTITION_NONE),
m_last_decrypted_block(UINT64_MAX)
{
_assert_(m_pReader);
if (m_pReader->ReadSwapped<u32>(0x60) != u32(0))
{
// No partitions - just read unencrypted data like with a GC disc
return;
}
for (u32 partition_group = 0; partition_group < 4; ++partition_group)
{
const std::optional<u32> number_of_partitions =
m_pReader->ReadSwapped<u32>(0x40000 + (partition_group * 8));
if (!number_of_partitions)
continue;
std::optional<u32> read_buffer =
m_pReader->ReadSwapped<u32>(0x40000 + (partition_group * 8) + 4);
if (!read_buffer)
continue;
const u64 partition_table_offset = static_cast<u64>(*read_buffer) << 2;
for (u32 i = 0; i < number_of_partitions; i++)
{
read_buffer = m_pReader->ReadSwapped<u32>(partition_table_offset + (i * 8));
if (!read_buffer)
continue;
const u64 partition_offset = static_cast<u64>(*read_buffer) << 2;
const Partition partition(partition_offset);
const std::optional<u32> partition_type =
m_pReader->ReadSwapped<u32>(partition_table_offset + (i * 8) + 4);
if (!partition_type)
continue;
// If this is the game partition, set m_game_partition
if (m_game_partition == PARTITION_NONE && *partition_type == 0)
m_game_partition = partition;
auto get_ticket = [this, partition]() -> IOS::ES::TicketReader {
std::vector<u8> ticket_buffer(sizeof(IOS::ES::Ticket));
if (!m_pReader->Read(partition.offset, ticket_buffer.size(), ticket_buffer.data()))
return INVALID_TICKET;
return IOS::ES::TicketReader{std::move(ticket_buffer)};
};
auto get_tmd = [this, partition]() -> IOS::ES::TMDReader {
const std::optional<u32> tmd_size = m_pReader->ReadSwapped<u32>(partition.offset + 0x2a4);
std::optional<u32> tmd_address = m_pReader->ReadSwapped<u32>(partition.offset + 0x2a8);
if (!tmd_size || !tmd_address)
return INVALID_TMD;
*tmd_address <<= 2;
if (!IOS::ES::IsValidTMDSize(*tmd_size))
{
// This check is normally done by ES in ES_DiVerify, but that would happen too late
// (after allocating the buffer), so we do the check here.
PanicAlert("Invalid TMD size");
return INVALID_TMD;
}
std::vector<u8> tmd_buffer(*tmd_size);
if (!m_pReader->Read(partition.offset + *tmd_address, *tmd_size, tmd_buffer.data()))
return INVALID_TMD;
return IOS::ES::TMDReader{std::move(tmd_buffer)};
};
auto get_key = [this, partition]() -> std::unique_ptr<mbedtls_aes_context> {
const IOS::ES::TicketReader& ticket = *m_partitions[partition].ticket;
if (!ticket.IsValid())
return nullptr;
const std::array<u8, 16> key = ticket.GetTitleKey();
std::unique_ptr<mbedtls_aes_context> aes_context = std::make_unique<mbedtls_aes_context>();
mbedtls_aes_setkey_dec(aes_context.get(), key.data(), 128);
return aes_context;
};
m_partitions.emplace(
partition, PartitionDetails{Common::Lazy<std::unique_ptr<mbedtls_aes_context>>(get_key),
Common::Lazy<IOS::ES::TicketReader>(get_ticket),
Common::Lazy<IOS::ES::TMDReader>(get_tmd), *partition_type});
}
}
}
VolumeWii::~VolumeWii()
{
}
bool VolumeWii::Read(u64 _ReadOffset, u64 _Length, u8* _pBuffer, const Partition& partition) const
{
if (partition == PARTITION_NONE)
return m_pReader->Read(_ReadOffset, _Length, _pBuffer);
if (m_pReader->SupportsReadWiiDecrypted())
return m_pReader->ReadWiiDecrypted(_ReadOffset, _Length, _pBuffer, partition.offset);
// Get the decryption key for the partition
auto it = m_partitions.find(partition);
if (it == m_partitions.end())
return false;
mbedtls_aes_context* aes_context = it->second.key->get();
if (!aes_context)
return false;
std::vector<u8> read_buffer(BLOCK_TOTAL_SIZE);
while (_Length > 0)
{
// Calculate offsets
u64 block_offset_on_disc =
partition.offset + PARTITION_DATA_OFFSET + _ReadOffset / BLOCK_DATA_SIZE * BLOCK_TOTAL_SIZE;
u64 data_offset_in_block = _ReadOffset % BLOCK_DATA_SIZE;
if (m_last_decrypted_block != block_offset_on_disc)
{
// Read the current block
if (!m_pReader->Read(block_offset_on_disc, BLOCK_TOTAL_SIZE, read_buffer.data()))
return false;
// Decrypt the block's data.
// 0x3D0 - 0x3DF in read_buffer will be overwritten,
// but that won't affect anything, because we won't
// use the content of read_buffer anymore after this
mbedtls_aes_crypt_cbc(aes_context, MBEDTLS_AES_DECRYPT, BLOCK_DATA_SIZE, &read_buffer[0x3D0],
&read_buffer[BLOCK_HEADER_SIZE], m_last_decrypted_block_data);
m_last_decrypted_block = block_offset_on_disc;
// The only thing we currently use from the 0x000 - 0x3FF part
// of the block is the IV (at 0x3D0), but it also contains SHA-1
// hashes that IOS uses to check that discs aren't tampered with.
// http://wiibrew.org/wiki/Wii_Disc#Encrypted
}
// Copy the decrypted data
u64 copy_size = std::min(_Length, BLOCK_DATA_SIZE - data_offset_in_block);
memcpy(_pBuffer, &m_last_decrypted_block_data[data_offset_in_block],
static_cast<size_t>(copy_size));
// Update offsets
_Length -= copy_size;
_pBuffer += copy_size;
_ReadOffset += copy_size;
}
return true;
}
std::vector<Partition> VolumeWii::GetPartitions() const
{
std::vector<Partition> partitions;
for (const auto& pair : m_partitions)
partitions.push_back(pair.first);
return partitions;
}
Partition VolumeWii::GetGamePartition() const
{
return m_game_partition;
}
std::optional<u32> VolumeWii::GetPartitionType(const Partition& partition) const
{
auto it = m_partitions.find(partition);
return it != m_partitions.end() ? it->second.type : std::optional<u32>();
}
std::optional<u64> VolumeWii::GetTitleID(const Partition& partition) const
{
const IOS::ES::TicketReader& ticket = GetTicket(partition);
if (!ticket.IsValid())
return {};
return ticket.GetTitleId();
}
const IOS::ES::TicketReader& VolumeWii::GetTicket(const Partition& partition) const
{
auto it = m_partitions.find(partition);
return it != m_partitions.end() ? *it->second.ticket : INVALID_TICKET;
}
const IOS::ES::TMDReader& VolumeWii::GetTMD(const Partition& partition) const
{
auto it = m_partitions.find(partition);
return it != m_partitions.end() ? *it->second.tmd : INVALID_TMD;
}
u64 VolumeWii::PartitionOffsetToRawOffset(u64 offset, const Partition& partition)
{
if (partition == PARTITION_NONE)
return offset;
return partition.offset + PARTITION_DATA_OFFSET + (offset / BLOCK_DATA_SIZE * BLOCK_TOTAL_SIZE) +
(offset % BLOCK_DATA_SIZE);
}
std::string VolumeWii::GetGameID(const Partition& partition) const
{
char ID[6];
if (!Read(0, 6, (u8*)ID, partition))
return std::string();
return DecodeString(ID);
}
Region VolumeWii::GetRegion() const
{
const std::optional<u32> region_code = m_pReader->ReadSwapped<u32>(0x4E000);
if (!region_code)
return Region::UNKNOWN_REGION;
const Region region = static_cast<Region>(*region_code);
return region <= Region::NTSC_K ? region : Region::UNKNOWN_REGION;
}
Country VolumeWii::GetCountry(const Partition& partition) const
{
// The 0 that we use as a default value is mapped to COUNTRY_UNKNOWN and UNKNOWN_REGION
u8 country_byte = ReadSwapped<u8>(3, partition).value_or(0);
const Region region = GetRegion();
if (RegionSwitchWii(country_byte) != region)
return TypicalCountryForRegion(region);
return CountrySwitch(country_byte);
}
std::string VolumeWii::GetMakerID(const Partition& partition) const
{
char makerID[2];
if (!Read(0x4, 0x2, (u8*)&makerID, partition))
return std::string();
return DecodeString(makerID);
}
std::optional<u16> VolumeWii::GetRevision(const Partition& partition) const
{
std::optional<u8> revision = ReadSwapped<u8>(7, partition);
return revision ? *revision : std::optional<u16>();
}
std::string VolumeWii::GetInternalName(const Partition& partition) const
{
char name_buffer[0x60];
if (Read(0x20, 0x60, (u8*)&name_buffer, partition))
return DecodeString(name_buffer);
return "";
}
std::map<Language, std::string> VolumeWii::GetLongNames() const
{
std::unique_ptr<FileSystem> file_system(CreateFileSystem(this, GetGamePartition()));
if (!file_system)
return {};
std::vector<u8> opening_bnr(NAMES_TOTAL_BYTES);
std::unique_ptr<FileInfo> file_info = file_system->FindFileInfo("opening.bnr");
opening_bnr.resize(ReadFile(*this, GetGamePartition(), file_info.get(), opening_bnr.data(),
opening_bnr.size(), 0x5C));
return ReadWiiNames(opening_bnr);
}
std::vector<u32> VolumeWii::GetBanner(int* width, int* height) const
{
*width = 0;
*height = 0;
const std::optional<u64> title_id = GetTitleID(GetGamePartition());
if (!title_id)
return std::vector<u32>();
return GetWiiBanner(width, height, *title_id);
}
std::string VolumeWii::GetApploaderDate(const Partition& partition) const
{
char date[16];
if (!Read(0x2440, 0x10, (u8*)&date, partition))
return std::string();
return DecodeString(date);
}
Platform VolumeWii::GetVolumeType() const
{
return Platform::WII_DISC;
}
std::optional<u8> VolumeWii::GetDiscNumber(const Partition& partition) const
{
return ReadSwapped<u8>(6, partition);
}
BlobType VolumeWii::GetBlobType() const
{
return m_pReader->GetBlobType();
}
u64 VolumeWii::GetSize() const
{
return m_pReader->GetDataSize();
}
u64 VolumeWii::GetRawSize() const
{
return m_pReader->GetRawSize();
}
bool VolumeWii::CheckIntegrity(const Partition& partition) const
{
// Get the decryption key for the partition
auto it = m_partitions.find(partition);
if (it == m_partitions.end())
return false;
mbedtls_aes_context* aes_context = it->second.key->get();
if (!aes_context)
return false;
// Get partition data size
u32 partSizeDiv4;
m_pReader->Read(partition.offset + 0x2BC, 4, (u8*)&partSizeDiv4);
u64 partDataSize = (u64)Common::swap32(partSizeDiv4) * 4;
u32 nClusters = (u32)(partDataSize / 0x8000);
for (u32 clusterID = 0; clusterID < nClusters; ++clusterID)
{
u64 clusterOff = partition.offset + PARTITION_DATA_OFFSET + (u64)clusterID * 0x8000;
// Read and decrypt the cluster metadata
u8 clusterMDCrypted[0x400];
u8 clusterMD[0x400];
u8 IV[16] = {0};
if (!m_pReader->Read(clusterOff, 0x400, clusterMDCrypted))
{
WARN_LOG(DISCIO, "Integrity Check: fail at cluster %d: could not read metadata", clusterID);
return false;
}
mbedtls_aes_crypt_cbc(aes_context, MBEDTLS_AES_DECRYPT, 0x400, IV, clusterMDCrypted, clusterMD);
// Some clusters have invalid data and metadata because they aren't
// meant to be read by the game (for example, holes between files). To
// try to avoid reporting errors because of these clusters, we check
// the 0x00 paddings in the metadata.
//
// This may cause some false negatives though: some bad clusters may be
// skipped because they are *too* bad and are not even recognized as
// valid clusters. To be improved.
bool meaningless = false;
for (u32 idx = 0x26C; idx < 0x280; ++idx)
if (clusterMD[idx] != 0)
meaningless = true;
if (meaningless)
continue;
u8 clusterData[0x7C00];
if (!Read((u64)clusterID * 0x7C00, 0x7C00, clusterData, partition))
{
WARN_LOG(DISCIO, "Integrity Check: fail at cluster %d: could not read data", clusterID);
return false;
}
for (u32 hashID = 0; hashID < 31; ++hashID)
{
u8 hash[20];
mbedtls_sha1(clusterData + hashID * 0x400, 0x400, hash);
// Note that we do not use strncmp here
if (memcmp(hash, clusterMD + hashID * 20, 20))
{
WARN_LOG(DISCIO, "Integrity Check: fail at cluster %d: hash %d is invalid", clusterID,
hashID);
return false;
}
}
}
return true;
}
} // namespace