Merge pull request #6947 from JosJuice/unencrypted-wii-disc

Make the support for unencrypted Wii disc images less broken

5 files changed, 65 insertions, 26 deletions

diff --git a/Source/Core/DiscIO/DirectoryBlob.cpp b/Source/Core/DiscIO/DirectoryBlob.cpp
index 61aac73694..8628c50fc0 100644
--- a/Source/Core/DiscIO/DirectoryBlob.cpp
+++ b/Source/Core/DiscIO/DirectoryBlob.cpp
@@ -54,6 +54,8 @@ enum class PartitionType : u32
 // 0xFF is an arbitrarily picked value. Note that we can't use 0x00, because that means NTSC-J
 constexpr u32 INVALID_REGION = 0xFF;
 
+constexpr u32 PARTITION_DATA_OFFSET = 0x20000;
+
 constexpr u8 ENTRY_SIZE = 0x0c;
 constexpr u8 FILE_ENTRY = 0;
 constexpr u8 DIRECTORY_ENTRY = 1;
@@ -508,8 +510,8 @@ void DirectoryBlobReader::SetPartitions(std::vector<PartitionWithType>&& partiti
 
     const u64 partition_data_size = partitions[i].partition.GetDataSize();
     m_partitions.emplace(partition_address, std::move(partitions[i].partition));
-    const u64 unaligned_next_partition_address =
-        VolumeWii::PartitionOffsetToRawOffset(partition_data_size, Partition(partition_address));
+    const u64 unaligned_next_partition_address = VolumeWii::EncryptedPartitionOffsetToRawOffset(
+        partition_data_size, Partition(partition_address), PARTITION_DATA_OFFSET);
     partition_address = Common::AlignUp(unaligned_next_partition_address, 0x10000ull);
   }
   m_data_size = partition_address;
@@ -546,7 +548,6 @@ void DirectoryBlobReader::SetPartitionHeader(const DirectoryBlobPartition& parti
                                           partition_root + "h3.bin");
 
   constexpr u32 PARTITION_HEADER_SIZE = 0x1c;
-  constexpr u32 DATA_OFFSET = 0x20000;
   const u64 data_size = Common::AlignUp(partition.GetDataSize(), 0x7c00) / 0x7c00 * 0x8000;
   m_partition_headers.emplace_back(PARTITION_HEADER_SIZE);
   std::vector<u8>& partition_header = m_partition_headers.back();
@@ -555,7 +556,7 @@ void DirectoryBlobReader::SetPartitionHeader(const DirectoryBlobPartition& parti
   Write32(static_cast<u32>(cert_size), 0x8, &partition_header);
   Write32(static_cast<u32>(cert_offset >> 2), 0x0C, &partition_header);
   Write32(H3_OFFSET >> 2, 0x10, &partition_header);
-  Write32(DATA_OFFSET >> 2, 0x14, &partition_header);
+  Write32(PARTITION_DATA_OFFSET >> 2, 0x14, &partition_header);
   Write32(static_cast<u32>(data_size >> 2), 0x18, &partition_header);
 
   m_nonpartition_contents.Add(partition_address + TICKET_SIZE, partition_header);
diff --git a/Source/Core/DiscIO/DiscExtractor.cpp b/Source/Core/DiscIO/DiscExtractor.cpp
index 7494bd5ab7..eaba17b68a 100644
--- a/Source/Core/DiscIO/DiscExtractor.cpp
+++ b/Source/Core/DiscIO/DiscExtractor.cpp
@@ -361,7 +361,8 @@ bool ExportSystemData(const Volume& volume, const Partition& partition,
     success &= ExportTicket(volume, partition, export_folder + "/ticket.bin");
     success &= ExportTMD(volume, partition, export_folder + "/tmd.bin");
     success &= ExportCertificateChain(volume, partition, export_folder + "/cert.bin");
-    success &= ExportH3Hashes(volume, partition, export_folder + "/h3.bin");
+    if (volume.IsEncryptedAndHashed())
+      success &= ExportH3Hashes(volume, partition, export_folder + "/h3.bin");
   }
 
   return success;
diff --git a/Source/Core/DiscIO/Volume.h b/Source/Core/DiscIO/Volume.h
index f1625a9681..2d800da31a 100644
--- a/Source/Core/DiscIO/Volume.h
+++ b/Source/Core/DiscIO/Volume.h
@@ -58,6 +58,7 @@ public:
     return temp ? static_cast<u64>(*temp) << GetOffsetShift() : std::optional<u64>();
   }
 
+  virtual bool IsEncryptedAndHashed() const { return false; }
   virtual std::vector<Partition> GetPartitions() const { return {}; }
   virtual Partition GetGamePartition() const { return PARTITION_NONE; }
   virtual std::optional<u32> GetPartitionType(const Partition& partition) const { return {}; }
@@ -70,6 +71,10 @@ public:
   virtual const IOS::ES::TMDReader& GetTMD(const Partition& partition) const { return INVALID_TMD; }
   // Returns a non-owning pointer. Returns nullptr if the file system couldn't be read.
   virtual const FileSystem* GetFileSystem(const Partition& partition) const = 0;
+  virtual u64 PartitionOffsetToRawOffset(u64 offset, const Partition& partition) const
+  {
+    return offset;
+  }
   std::string GetGameID() const { return GetGameID(GetGamePartition()); }
   virtual std::string GetGameID(const Partition& partition) const = 0;
   std::string GetMakerID() const { return GetMakerID(GetGamePartition()); }
diff --git a/Source/Core/DiscIO/VolumeWii.cpp b/Source/Core/DiscIO/VolumeWii.cpp
index d4558c0c99..9816b0cb66 100644
--- a/Source/Core/DiscIO/VolumeWii.cpp
+++ b/Source/Core/DiscIO/VolumeWii.cpp
@@ -33,19 +33,13 @@
 
 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;
-  }
+  m_encrypted = m_pReader->ReadSwapped<u32>(0x60) == u32(0);
 
   for (u32 partition_group = 0; partition_group < 4; ++partition_group)
   {
@@ -118,12 +112,16 @@ VolumeWii::VolumeWii(std::unique_ptr<BlobReader> reader)
         return file_system->IsValid() ? std::move(file_system) : nullptr;
       };
 
+      auto get_data_offset = [this, partition]() -> u64 {
+        return ReadSwappedAndShifted(partition.offset + 0x2b8, PARTITION_NONE).value_or(0);
+      };
+
       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),
                                       Common::Lazy<std::unique_ptr<FileSystem>>(get_file_system),
-                                      *partition_type});
+                                      Common::Lazy<u64>(get_data_offset), *partition_type});
     }
   }
 }
@@ -137,14 +135,21 @@ bool VolumeWii::Read(u64 _ReadOffset, u64 _Length, u8* _pBuffer, const Partition
   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();
+  const PartitionDetails& partition_details = it->second;
+
+  if (!m_encrypted)
+  {
+    return m_pReader->Read(partition.offset + *partition_details.data_offset + _ReadOffset, _Length,
+                           _pBuffer);
+  }
+
+  if (m_pReader->SupportsReadWiiDecrypted())
+    return m_pReader->ReadWiiDecrypted(_ReadOffset, _Length, _pBuffer, partition.offset);
+
+  mbedtls_aes_context* aes_context = partition_details.key->get();
   if (!aes_context)
     return false;
 
@@ -152,8 +157,8 @@ bool VolumeWii::Read(u64 _ReadOffset, u64 _Length, u8* _pBuffer, const Partition
   while (_Length > 0)
   {
     // Calculate offsets
-    u64 block_offset_on_disc =
-        partition.offset + PARTITION_DATA_OFFSET + _ReadOffset / BLOCK_DATA_SIZE * BLOCK_TOTAL_SIZE;
+    u64 block_offset_on_disc = partition.offset + *partition_details.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)
@@ -190,6 +195,11 @@ bool VolumeWii::Read(u64 _ReadOffset, u64 _Length, u8* _pBuffer, const Partition
   return true;
 }
 
+bool VolumeWii::IsEncryptedAndHashed() const
+{
+  return m_encrypted;
+}
+
 std::vector<Partition> VolumeWii::GetPartitions() const
 {
   std::vector<Partition> partitions;
@@ -235,15 +245,29 @@ const FileSystem* VolumeWii::GetFileSystem(const Partition& partition) const
   return it != m_partitions.end() ? it->second.file_system->get() : nullptr;
 }
 
-u64 VolumeWii::PartitionOffsetToRawOffset(u64 offset, const Partition& partition)
+u64 VolumeWii::EncryptedPartitionOffsetToRawOffset(u64 offset, const Partition& partition,
+                                                   u64 partition_data_offset)
 {
   if (partition == PARTITION_NONE)
     return offset;
 
-  return partition.offset + PARTITION_DATA_OFFSET + (offset / BLOCK_DATA_SIZE * BLOCK_TOTAL_SIZE) +
+  return partition.offset + partition_data_offset + (offset / BLOCK_DATA_SIZE * BLOCK_TOTAL_SIZE) +
          (offset % BLOCK_DATA_SIZE);
 }
 
+u64 VolumeWii::PartitionOffsetToRawOffset(u64 offset, const Partition& partition) const
+{
+  auto it = m_partitions.find(partition);
+  if (it == m_partitions.end())
+    return offset;
+  const u64 data_offset = *it->second.data_offset;
+
+  if (!m_encrypted)
+    return partition.offset + data_offset + offset;
+
+  return EncryptedPartitionOffsetToRawOffset(offset, partition, data_offset);
+}
+
 std::string VolumeWii::GetGameID(const Partition& partition) const
 {
   char ID[6];
@@ -357,11 +381,15 @@ u64 VolumeWii::GetRawSize() const
 
 bool VolumeWii::CheckIntegrity(const Partition& partition) const
 {
+  if (!m_encrypted)
+    return false;
+
   // 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();
+  const PartitionDetails& partition_details = it->second;
+  mbedtls_aes_context* aes_context = partition_details.key->get();
   if (!aes_context)
     return false;
 
@@ -373,7 +401,7 @@ bool VolumeWii::CheckIntegrity(const Partition& partition) const
   u32 nClusters = (u32)(partDataSize / 0x8000);
   for (u32 clusterID = 0; clusterID < nClusters; ++clusterID)
   {
-    u64 clusterOff = partition.offset + PARTITION_DATA_OFFSET + (u64)clusterID * 0x8000;
+    u64 clusterOff = partition.offset + *partition_details.data_offset + (u64)clusterID * 0x8000;
 
     // Read and decrypt the cluster metadata
     u8 clusterMDCrypted[0x400];
diff --git a/Source/Core/DiscIO/VolumeWii.h b/Source/Core/DiscIO/VolumeWii.h
index a173d17aa7..ede26959f9 100644
--- a/Source/Core/DiscIO/VolumeWii.h
+++ b/Source/Core/DiscIO/VolumeWii.h
@@ -33,6 +33,7 @@ public:
   VolumeWii(std::unique_ptr<BlobReader> reader);
   ~VolumeWii();
   bool Read(u64 _Offset, u64 _Length, u8* _pBuffer, const Partition& partition) const override;
+  bool IsEncryptedAndHashed() const override;
   std::vector<Partition> GetPartitions() const override;
   Partition GetGamePartition() const override;
   std::optional<u32> GetPartitionType(const Partition& partition) const override;
@@ -40,6 +41,9 @@ public:
   const IOS::ES::TicketReader& GetTicket(const Partition& partition) const override;
   const IOS::ES::TMDReader& GetTMD(const Partition& partition) const override;
   const FileSystem* GetFileSystem(const Partition& partition) const override;
+  static u64 EncryptedPartitionOffsetToRawOffset(u64 offset, const Partition& partition,
+                                                 u64 partition_data_offset);
+  u64 PartitionOffsetToRawOffset(u64 offset, const Partition& partition) const override;
   std::string GetGameID(const Partition& partition) const override;
   std::string GetMakerID(const Partition& partition) const override;
   std::optional<u16> GetRevision(const Partition& partition) const override;
@@ -59,8 +63,6 @@ public:
   u64 GetSize() const override;
   u64 GetRawSize() const override;
 
-  static u64 PartitionOffsetToRawOffset(u64 offset, const Partition& partition);
-
   static constexpr unsigned int BLOCK_HEADER_SIZE = 0x0400;
   static constexpr unsigned int BLOCK_DATA_SIZE = 0x7C00;
   static constexpr unsigned int BLOCK_TOTAL_SIZE = BLOCK_HEADER_SIZE + BLOCK_DATA_SIZE;
@@ -75,12 +77,14 @@ private:
     Common::Lazy<IOS::ES::TicketReader> ticket;
     Common::Lazy<IOS::ES::TMDReader> tmd;
     Common::Lazy<std::unique_ptr<FileSystem>> file_system;
+    Common::Lazy<u64> data_offset;
     u32 type;
   };
 
   std::unique_ptr<BlobReader> m_pReader;
   std::map<Partition, PartitionDetails> m_partitions;
   Partition m_game_partition;
+  bool m_encrypted;
 
   mutable u64 m_last_decrypted_block;
   mutable u8 m_last_decrypted_block_data[BLOCK_DATA_SIZE];