Support for Wii U VC NFS images

include/nod/IDiscIO.hpp

@@ -28,6 +28,7 @@ public:
   virtual ~IDiscIO() = default;
   virtual std::unique_ptr<IReadStream> beginReadStream(uint64_t offset = 0) const = 0;
   virtual std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset = 0) const = 0;
+  virtual bool hasWiiCrypto() const { return true; } /* NFS overrides this to false */
 };
 
 struct IPartReadStream : IReadStream {

lib/CMakeLists.txt

@@ -6,6 +6,7 @@ add_library(nod
   DiscBase.cpp
   DiscGCN.cpp
   DiscIOISO.cpp
+  DiscIONFS.cpp
   DiscIOWBFS.cpp
   DiscWii.cpp
   nod.cpp

lib/DiscIOISO.cpp

@@ -28,9 +28,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_fio->beginReadStream(offset), err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }
@@ -51,9 +50,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IWriteStream>(new WriteStream(m_fio->beginWriteStream(offset), err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }

lib/DiscIONFS.cpp

@@ -0,0 +1,282 @@
+#include "nod/IDiscIO.hpp"
+#include "nod/IFileIO.hpp"
+#include "nod/Util.hpp"
+#include "nod/aes.hpp"
+
+#include <logvisor/logvisor.hpp>
+
+#include <array>
+
+namespace nod {
+
+/*
+ * NFS is the image format used to distribute Wii VC games for the Wii U.
+ * It is an LBA format similar to WBFS but adds its own encryption layer.
+ * It logically stores a standard Wii disc image with partitions.
+ */
+
+class DiscIONFS : public IDiscIO {
+  struct DiscIONFSShared {
+    std::vector<std::unique_ptr<IFileIO>> files;
+
+    struct NFSHead {
+      uint32_t magic; // EGGS
+      uint32_t version;
+      uint32_t unknown[2]; // Signature, UUID?
+      uint32_t lbaRangeCount;
+      struct {
+        uint32_t startBlock;
+        uint32_t numBlocks;
+      } lbaRanges[61];
+      uint32_t endMagic; // SGGE
+    } nfsHead;
+
+    uint8_t key[16];
+
+    uint32_t calculateNumFiles() const {
+      uint32_t totalSectorCount = 0;
+      for (uint32_t i = 0; i < nfsHead.lbaRangeCount; ++i) {
+        const auto& range = nfsHead.lbaRanges[i];
+        totalSectorCount += range.numBlocks;
+      }
+      return (uint64_t(totalSectorCount) * uint64_t(0x8000) +
+              (uint64_t(0x200) + uint64_t(0xF9FFFFF))) / uint64_t(0xFA00000);
+    }
+
+    struct FBO {
+      uint32_t file, block, offset;
+    };
+
+    FBO logicalToFBO(uint64_t offset) const {
+      auto sectorAndRemBytes = std::lldiv(offset, 0x8000); /* 32768 bytes per block */
+      uint32_t i, physicalBlock;
+      for (i = 0, physicalBlock = 0; i < nfsHead.lbaRangeCount; ++i) {
+        const auto& range = nfsHead.lbaRanges[i];
+        if (sectorAndRemBytes.quot >= range.startBlock &&
+            sectorAndRemBytes.quot - range.startBlock < range.numBlocks) {
+          sectorAndRemBytes.quot = physicalBlock + (sectorAndRemBytes.quot - range.startBlock);
+          break;
+        }
+        physicalBlock += range.numBlocks;
+      }
+      /* This offset has no physical mapping, read zeroes */
+      if (i == nfsHead.lbaRangeCount)
+        return {UINT32_MAX, UINT32_MAX, UINT32_MAX};
+      auto fileAndRemBlocks = std::lldiv(sectorAndRemBytes.quot, 8000); /* 8000 blocks per file */
+      return {uint32_t(fileAndRemBlocks.quot), uint32_t(fileAndRemBlocks.rem), uint32_t(sectorAndRemBytes.rem)};
+    }
+
+    DiscIONFSShared(SystemStringView fpin, bool& err) {
+      /* Validate file path format */
+      using SignedSize = std::make_signed<SystemString::size_type>::type;
+      const auto dotPos = SignedSize(fpin.rfind('.'));
+      const auto slashPos = SignedSize(fpin.rfind("/\\"));
+      if (fpin.size() <= 4 || dotPos == -1 || dotPos <= slashPos ||
+          fpin.compare(slashPos + 1, 4, "hif_") ||
+          fpin.compare(dotPos, fpin.size() - dotPos, ".nfs")) {
+        LogModule.report(logvisor::Error,
+                         fmt("'{}' must begin with 'hif_' and end with '.nfs' to be accepted as an NFS image"), fpin);
+        err = true;
+        return;
+      }
+
+      /* Load key file */
+      const SystemString dir(fpin.begin(), fpin.begin() + slashPos + 1);
+      auto keyFile = NewFileIO(dir + "../code/htk.bin")->beginReadStream();
+      if (!keyFile)
+        keyFile = NewFileIO(dir + "htk.bin")->beginReadStream();
+      if (!keyFile) {
+        LogModule.report(logvisor::Error, fmt("Unable to open '{}../code/htk.bin' or '{}htk.bin'"), dir, dir);
+        err = true;
+        return;
+      }
+      if (keyFile->read(key, 16) != 16) {
+        LogModule.report(logvisor::Error, fmt("Unable to read from '{}../code/htk.bin' or '{}htk.bin'"), dir, dir);
+        err = true;
+        return;
+      }
+
+      /* Load header from first file */
+      const SystemString firstPath = fmt::format(fmt("{}hif_{:06}.nfs"), dir, 0);
+      files.push_back(NewFileIO(firstPath));
+      auto rs = files.back()->beginReadStream();
+      if (!rs) {
+        LogModule.report(logvisor::Error, fmt("'{}' does not exist"), firstPath);
+        err = true;
+        return;
+      }
+      if (rs->read(&nfsHead, 0x200) != 0x200) {
+        LogModule.report(logvisor::Error, fmt("Unable to read header from '{}'"), firstPath);
+        err = true;
+        return;
+      }
+      if (std::memcmp(&nfsHead.magic, "EGGS", 4)) {
+        LogModule.report(logvisor::Error, fmt("Invalid magic in '{}'"), firstPath);
+        err = true;
+        return;
+      }
+      nfsHead.lbaRangeCount = SBig(nfsHead.lbaRangeCount);
+      for (uint32_t i = 0; i < nfsHead.lbaRangeCount; ++i) {
+        auto& range = nfsHead.lbaRanges[i];
+        range.startBlock = SBig(range.startBlock);
+        range.numBlocks = SBig(range.numBlocks);
+      }
+
+      /* Ensure remaining files exist */
+      const uint32_t numFiles = calculateNumFiles();
+      files.reserve(numFiles);
+      for (uint32_t i = 1; i < numFiles; ++i) {
+        SystemString path = fmt::format(fmt("{}hif_{:06}.nfs"), dir, i);
+        files.push_back(NewFileIO(path));
+        if (!files.back()->exists()) {
+          LogModule.report(logvisor::Error, fmt("'{}' does not exist"), path);
+          err = true;
+          return;
+        }
+      }
+    }
+  };
+  std::shared_ptr<DiscIONFSShared> m_shared;
+
+public:
+  DiscIONFS(SystemStringView fpin, bool& err) : m_shared(std::make_shared<DiscIONFSShared>(fpin, err)) {}
+
+  class ReadStream : public IReadStream {
+    friend class DiscIONFS;
+    std::shared_ptr<DiscIONFSShared> m_shared;
+    std::unique_ptr<IReadStream> m_rs;
+    std::unique_ptr<IAES> m_aes;
+
+    /* Physical address - all UINT32_MAX indicates logical zero block */
+    DiscIONFSShared::FBO m_physAddr;
+
+    /* Logical address */
+    uint64_t m_offset;
+
+    /* Active file stream and its offset as set in the system.
+     * Block is typically one ahead of the presently decrypted block. */
+    uint32_t m_curFile = UINT32_MAX;
+    uint32_t m_curBlock = UINT32_MAX;
+
+    ReadStream(std::shared_ptr<DiscIONFSShared> shared, uint64_t offset, bool& err)
+    : m_shared(std::move(shared)), m_aes(NewAES()),
+      m_physAddr({UINT32_MAX, UINT32_MAX, UINT32_MAX}), m_offset(offset) {
+      m_aes->setKey(m_shared->key);
+      setNewLogicalAddr(offset);
+    }
+
+    uint8_t m_encBuf[0x8000] = {};
+    uint8_t m_decBuf[0x8000] = {};
+
+    void setCurFile(uint32_t curFile) {
+      if (curFile >= m_shared->files.size()) {
+        LogModule.report(logvisor::Error, fmt("Out of bounds NFS file access"));
+        return;
+      }
+      m_curFile = curFile;
+      m_curBlock = UINT32_MAX;
+      m_rs = m_shared->files[m_curFile]->beginReadStream();
+    }
+
+    void setCurBlock(uint32_t curBlock) {
+      m_curBlock = curBlock;
+      m_rs->seek(m_curBlock * 0x8000 + 0x200);
+    }
+
+    void setNewPhysicalAddr(DiscIONFSShared::FBO physAddr) {
+      /* If we're just changing the offset, nothing else needs to be done */
+      if (m_physAddr.file == physAddr.file && m_physAddr.block == physAddr.block) {
+        m_physAddr.offset = physAddr.offset;
+        return;
+      }
+      m_physAddr = physAddr;
+
+      /* Set logical zero block */
+      if (m_physAddr.file == UINT32_MAX) {
+        memset(m_decBuf, 0, 0x8000);
+        return;
+      }
+
+      /* Make necessary file and block current with system */
+      if (m_physAddr.file != m_curFile)
+        setCurFile(m_physAddr.file);
+      if (m_physAddr.block != m_curBlock)
+        setCurBlock(m_physAddr.block);
+
+      /* Read block, handling 0x200 overlap case */
+      if (m_physAddr.block == 7999) {
+        m_rs->read(m_encBuf, 0x7E00);
+        setCurFile(m_curFile + 1);
+        m_rs->read(m_encBuf + 0x7E00, 0x200);
+        m_curBlock = 0;
+      } else {
+        m_rs->read(m_encBuf, 0x8000);
+        ++m_curBlock;
+      }
+
+      /* Decrypt */
+      const uint32_t ivBuf[] = {0, 0, 0, SBig(m_physAddr.block)};
+      m_aes->decrypt((const uint8_t*)ivBuf, m_encBuf, m_decBuf, 0x8000);
+    }
+
+    void setNewLogicalAddr(uint64_t addr) {
+      setNewPhysicalAddr(m_shared->logicalToFBO(m_offset));
+    }
+
+  public:
+    uint64_t read(void* buf, uint64_t length) override {
+      uint64_t rem = length;
+      uint8_t* dst = (uint8_t*)buf;
+
+      /* Perform reads on block boundaries */
+      while (rem) {
+        uint64_t readSize = rem;
+        uint32_t blockOffset = (m_physAddr.offset == UINT32_MAX) ? 0 : m_physAddr.offset;
+        if (readSize + blockOffset > 0x8000)
+          readSize = 0x8000 - blockOffset;
+
+        memmove(dst, m_decBuf + blockOffset, readSize);
+        dst += readSize;
+        rem -= readSize;
+        m_offset += readSize;
+        setNewLogicalAddr(m_offset);
+      }
+
+      return dst - (uint8_t*)buf;
+    }
+    uint64_t position() const override { return m_offset; }
+    void seek(int64_t offset, int whence) override {
+      if (whence == SEEK_SET)
+        m_offset = offset;
+      else if (whence == SEEK_CUR)
+        m_offset += offset;
+      else
+        return;
+      setNewLogicalAddr(m_offset);
+    }
+  };
+
+  std::unique_ptr<IReadStream> beginReadStream(uint64_t offset) const override {
+    bool err = false;
+    auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_shared, offset, err));
+
+    if (err)
+      return {};
+
+    return ret;
+  }
+
+  std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset) const override { return {}; }
+
+  bool hasWiiCrypto() const override { return false; }
+};
+
+std::unique_ptr<IDiscIO> NewDiscIONFS(SystemStringView path) {
+  bool err = false;
+  auto ret = std::make_unique<DiscIONFS>(path, err);
+  if (err)
+    return {};
+  return ret;
+}
+
+}

lib/DiscIOWBFS.cpp

@@ -23,7 +23,7 @@ static uint8_t size_to_shift(uint32_t size) {
 }
 
 class DiscIOWBFS : public IDiscIO {
-  SystemString filepath;
+  std::unique_ptr<IFileIO> m_fio;
 
   struct WBFSHead {
     uint32_t magic;
@@ -83,10 +83,9 @@ class DiscIOWBFS : public IDiscIO {
   }
 
 public:
-  DiscIOWBFS(SystemStringView fpin) : filepath(fpin) {
+  DiscIOWBFS(SystemStringView fpin) : m_fio(NewFileIO(fpin)) {
     /* Temporary file handle to read LBA table */
-    std::unique_ptr<IFileIO> fio = NewFileIO(filepath);
+    std::unique_ptr<IFileIO::IReadStream> rs = m_fio->beginReadStream();
-    std::unique_ptr<IFileIO::IReadStream> rs = fio->beginReadStream();
     if (!rs)
       return;
 
@@ -265,16 +264,15 @@ public:
 
   std::unique_ptr<IReadStream> beginReadStream(uint64_t offset) const override {
     bool err = false;
-    auto ret = std::unique_ptr<IReadStream>(new ReadStream(*this, NewFileIO(filepath)->beginReadStream(), offset, err));
+    auto ret = std::unique_ptr<IReadStream>(new ReadStream(*this, m_fio->beginReadStream(), offset, err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }
 
-  std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset) const override { return nullptr; }
+  std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset) const override { return {}; }
 };
 
 std::unique_ptr<IDiscIO> NewDiscIOWBFS(SystemStringView path) { return std::make_unique<DiscIOWBFS>(path); }

lib/DiscWii.cpp

@@ -332,14 +332,22 @@ public:
     uint8_t m_decBuf[0x7c00];
 
     void decryptBlock() {
+      if (m_aes) {
         m_dio->read(m_encBuf, 0x8000);
         m_aes->decrypt(&m_encBuf[0x3d0], &m_encBuf[0x400], m_decBuf, 0x7c00);
+      } else {
+        m_dio->seek(0x400, SEEK_CUR);
+        m_dio->read(m_decBuf, 0x7c00);
+      }
     }
 
   public:
     PartReadStream(const PartitionWii& parent, uint64_t baseOffset, uint64_t offset, bool& err)
-    : m_aes(NewAES()), m_parent(parent), m_baseOffset(baseOffset), m_offset(offset) {
+    : m_parent(parent), m_baseOffset(baseOffset), m_offset(offset) {
+      if (m_parent.m_parent.getDiscIO().hasWiiCrypto()) {
+        m_aes = NewAES();
         m_aes->setKey(parent.m_decKey);
+      }
       size_t block = m_offset / 0x7c00;
       m_dio = m_parent.m_parent.getDiscIO().beginReadStream(m_baseOffset + block * 0x8000);
       if (!m_dio) {
@@ -365,27 +373,25 @@ public:
     }
     uint64_t position() const override { return m_offset; }
     uint64_t read(void* buf, uint64_t length) override {
-      size_t block = m_offset / 0x7c00;
+      auto blockAndRemOff = std::lldiv(m_offset, 0x7c00);
-      size_t cacheOffset = m_offset % 0x7c00;
-      uint64_t cacheSize;
       uint64_t rem = length;
       uint8_t* dst = (uint8_t*)buf;
 
       while (rem) {
-        if (block != m_curBlock) {
+        if (blockAndRemOff.quot != m_curBlock) {
           decryptBlock();
-          m_curBlock = block;
+          m_curBlock = blockAndRemOff.quot;
         }
 
-        cacheSize = rem;
+        uint64_t cacheSize = rem;
-        if (cacheSize + cacheOffset > 0x7c00)
+        if (cacheSize + blockAndRemOff.rem > 0x7c00)
-          cacheSize = 0x7c00 - cacheOffset;
+          cacheSize = 0x7c00 - blockAndRemOff.rem;
 
-        memmove(dst, m_decBuf + cacheOffset, cacheSize);
+        memmove(dst, m_decBuf + blockAndRemOff.rem, cacheSize);
         dst += cacheSize;
         rem -= cacheSize;
-        cacheOffset = 0;
+        blockAndRemOff.rem = 0;
-        ++block;
+        ++blockAndRemOff.quot;
       }
 
       m_offset += length;

lib/FileIOFILE.cpp

@@ -77,9 +77,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IWriteStream>(new WriteStream(m_path, m_maxWriteSize, err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }
@@ -88,9 +87,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IWriteStream>(new WriteStream(m_path, offset, m_maxWriteSize, err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }
@@ -137,9 +135,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_path, err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }
@@ -148,9 +145,8 @@ public:
     bool err = false;
     auto ret = std::unique_ptr<IReadStream>(new ReadStream(m_path, offset, err));
 
-    if (err) {
+    if (err)
-      return nullptr;
+      return {};
-    }
 
     return ret;
   }

lib/nod.cpp

@@ -12,6 +12,7 @@ logvisor::Module LogModule("nod");
 
 std::unique_ptr<IDiscIO> NewDiscIOISO(SystemStringView path);
 std::unique_ptr<IDiscIO> NewDiscIOWBFS(SystemStringView path);
+std::unique_ptr<IDiscIO> NewDiscIONFS(SystemStringView path);
 
 std::unique_ptr<DiscBase> OpenDiscFromImage(SystemStringView path, bool& isWii) {
   /* Temporary file handle to determine image type */
@@ -32,9 +33,17 @@ std::unique_ptr<DiscBase> OpenDiscFromImage(SystemStringView path, bool& isWii)
     return {};
   }
 
+  using SignedSize = std::make_signed<SystemString::size_type>::type;
+  const auto dotPos = SignedSize(path.rfind('.'));
+  const auto slashPos = SignedSize(path.rfind("/\\"));
   if (magic == nod::SBig((uint32_t)'WBFS')) {
     discIO = NewDiscIOWBFS(path);
     isWii = true;
+  } else if (path.size() > 4 && dotPos != -1 && dotPos > slashPos &&
+             !path.compare(slashPos + 1, 4, "hif_") &&
+             !path.compare(dotPos, path.size() - dotPos, ".nfs")) {
+    discIO = NewDiscIONFS(path);
+    isWii = true;
   } else {
     rs->seek(0x18, SEEK_SET);
     rs->read(&magic, 4);