Merge pull request #9313 from leoetlino/check-content-hashes

WiiUtils: Check hashes to determine if a title is installed and up-to-date

Source/Core/Core/IOS/ES/ES.h

@@ -81,6 +81,12 @@ public:
     s32 ipc_fd = -1;
   };
 
+  enum class CheckContentHashes : bool
+  {
+    Yes = true,
+    No = false,
+  };
+
   IOS::ES::TMDReader FindImportTMD(u64 title_id) const;
   IOS::ES::TMDReader FindInstalledTMD(u64 title_id) const;
   IOS::ES::TicketReader FindSignedTicket(u64 title_id) const;
@@ -92,7 +98,9 @@ public:
   // Get titles for which there is a ticket (in /ticket).
   std::vector<u64> GetTitlesWithTickets() const;
 
-  std::vector<IOS::ES::Content> GetStoredContentsFromTMD(const IOS::ES::TMDReader& tmd) const;
+  std::vector<IOS::ES::Content>
+  GetStoredContentsFromTMD(const IOS::ES::TMDReader& tmd,
+                           CheckContentHashes check_content_hashes = CheckContentHashes::No) const;
   u32 GetSharedContentsCount() const;
   std::vector<std::array<u8, 20>> GetSharedContents() const;
 

Source/Core/Core/IOS/ES/NandUtils.cpp

@@ -12,6 +12,7 @@
 #include <vector>
 
 #include <fmt/format.h>
+#include <mbedtls/sha1.h>
 
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
@@ -163,7 +164,9 @@ std::vector<u64> ES::GetTitlesWithTickets() const
   return title_ids;
 }
 
-std::vector<IOS::ES::Content> ES::GetStoredContentsFromTMD(const IOS::ES::TMDReader& tmd) const
+std::vector<IOS::ES::Content>
+ES::GetStoredContentsFromTMD(const IOS::ES::TMDReader& tmd,
+                             CheckContentHashes check_content_hashes) const
 {
   if (!tmd.IsValid())
     return {};
@@ -174,10 +177,29 @@ std::vector<IOS::ES::Content> ES::GetStoredContentsFromTMD(const IOS::ES::TMDRea
   std::vector<IOS::ES::Content> stored_contents;
 
   std::copy_if(contents.begin(), contents.end(), std::back_inserter(stored_contents),
-               [this, &tmd, &map](const IOS::ES::Content& content) {
+               [this, &tmd, &map, check_content_hashes](const IOS::ES::Content& content) {
+                 const auto fs = m_ios.GetFS();
+
                  const std::string path = GetContentPath(tmd.GetTitleId(), content, map);
-                 return !path.empty() &&
-                        m_ios.GetFS()->GetMetadata(PID_KERNEL, PID_KERNEL, path).Succeeded();
+                 if (path.empty())
+                   return false;
+
+                 // Check whether the content file exists.
+                 const auto file = fs->OpenFile(PID_KERNEL, PID_KERNEL, path, FS::Mode::Read);
+                 if (!file.Succeeded())
+                   return false;
+
+                 // If content hash checks are disabled, all we have to do is check for existence.
+                 if (check_content_hashes == CheckContentHashes::No)
+                   return true;
+
+                 // Otherwise, check whether the installed content SHA1 matches the expected hash.
+                 std::vector<u8> content_data(file->GetStatus()->size);
+                 if (!file->Read(content_data.data(), content_data.size()))
+                   return false;
+                 std::array<u8, 20> sha1{};
+                 mbedtls_sha1_ret(content_data.data(), content_data.size(), sha1.data());
+                 return sha1 == content.sha1;
                });
 
   return stored_contents;

Source/Core/Core/IOS/FS/FileSystem.h

@@ -205,6 +205,7 @@ public:
   /// Reposition the file offset for a file descriptor.
   virtual Result<u32> SeekFile(Fd fd, u32 offset, SeekMode mode) = 0;
   /// Get status for a file descriptor.
+  /// Guaranteed to succeed for a valid file descriptor.
   virtual Result<FileStatus> GetFileStatus(Fd fd) = 0;
 
   /// Create a file with the specified path and metadata.

Source/Core/Core/WiiUtils.cpp

@@ -149,7 +149,8 @@ bool InstallWAD(IOS::HLE::Kernel& ios, const DiscIO::VolumeWAD& wad, InstallType
   const u64 title_id = wad.GetTMD().GetTitleId();
 
   // Skip the install if the WAD is already installed.
-  const auto installed_contents = ios.GetES()->GetStoredContentsFromTMD(wad.GetTMD());
+  const auto installed_contents = ios.GetES()->GetStoredContentsFromTMD(
+      wad.GetTMD(), IOS::HLE::Device::ES::CheckContentHashes::Yes);
   if (wad.GetTMD().GetContents() == installed_contents)
   {
     // Clear the "temporary title ID" flag in case the user tries to permanently install a title