scripted-diff: unify xor-vs-obfuscation nomenclature

Mechanical refactor of the low-level "xor" wording to signal the intent instead of the implementation used.
The renames are ordered by heaviest-hitting substitutions first, and were constructed such that after each replacement the code is still compilable.

-BEGIN VERIFY SCRIPT-
sed -i \
  -e 's/\bGetObfuscateKey\b/GetObfuscation/g' \
  -e 's/\bxor_key\b/obfuscation/g' \
  -e 's/\bxor_pat\b/obfuscation/g' \
  -e 's/\bm_xor_key\b/m_obfuscation/g' \
  -e 's/\bm_xor\b/m_obfuscation/g' \
  -e 's/\bobfuscate_key\b/m_obfuscation/g' \
  -e 's/\bOBFUSCATE_KEY_KEY\b/OBFUSCATION_KEY_KEY/g' \
  -e 's/\bSetXor(/SetObfuscation(/g' \
  -e 's/\bdata_xor\b/obfuscation/g' \
  -e 's/\bCreateObfuscateKey\b/CreateObfuscation/g' \
  -e 's/\bobfuscate key\b/obfuscation key/g' \
  $(git ls-files '*.cpp' '*.h')
-END VERIFY SCRIPT-

Author: l0rinc

src/dbwrapper.cpp

@@ -174,7 +174,7 @@ void CDBBatch::Clear()
 void CDBBatch::WriteImpl(std::span<const std::byte> key, DataStream& ssValue)
 {
     leveldb::Slice slKey(CharCast(key.data()), key.size());
-    ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
+    ssValue.Xor(dbwrapper_private::GetObfuscation(parent));
     leveldb::Slice slValue(CharCast(ssValue.data()), ssValue.size());
     m_impl_batch->batch.Put(slKey, slValue);
 }
@@ -250,23 +250,23 @@ CDBWrapper::CDBWrapper(const DBParams& params)
     }
 
     // The base-case obfuscation key, which is a noop.
-    obfuscate_key = std::vector<unsigned char>(Obfuscation::KEY_SIZE, '\000');
+    m_obfuscation = std::vector<unsigned char>(Obfuscation::KEY_SIZE, '\000');
 
-    bool key_exists = Read(OBFUSCATE_KEY_KEY, obfuscate_key);
+    bool key_exists = Read(OBFUSCATION_KEY_KEY, m_obfuscation);
 
     if (!key_exists && params.obfuscate && IsEmpty()) {
         // Initialize non-degenerate obfuscation if it won't upset
         // existing, non-obfuscated data.
-        std::vector<unsigned char> new_key = CreateObfuscateKey();
+        std::vector<unsigned char> new_key = CreateObfuscation();
 
         // Write `new_key` so we don't obfuscate the key with itself
-        Write(OBFUSCATE_KEY_KEY, new_key);
-        obfuscate_key = new_key;
+        Write(OBFUSCATION_KEY_KEY, new_key);
+        m_obfuscation = new_key;
 
-        LogPrintf("Wrote new obfuscate key for %s: %s\n", fs::PathToString(params.path), HexStr(obfuscate_key));
+        LogPrintf("Wrote new obfuscation key for %s: %s\n", fs::PathToString(params.path), HexStr(m_obfuscation));
     }
 
-    LogPrintf("Using obfuscation key for %s: %s\n", fs::PathToString(params.path), HexStr(obfuscate_key));
+    LogPrintf("Using obfuscation key for %s: %s\n", fs::PathToString(params.path), HexStr(m_obfuscation));
 }
 
 CDBWrapper::~CDBWrapper()
@@ -315,13 +315,13 @@ size_t CDBWrapper::DynamicMemoryUsage() const
 //
 // We must use a string constructor which specifies length so that we copy
 // past the null-terminator.
-const std::string CDBWrapper::OBFUSCATE_KEY_KEY("\000obfuscate_key", 14);
+const std::string CDBWrapper::OBFUSCATION_KEY_KEY("\000obfuscate_key", 14);
 
 /**
  * Returns a string (consisting of 8 random bytes) suitable for use as an
  * obfuscating XOR key.
  */
-std::vector<unsigned char> CDBWrapper::CreateObfuscateKey() const
+std::vector<unsigned char> CDBWrapper::CreateObfuscation() const
 {
     std::vector<uint8_t> ret(Obfuscation::KEY_SIZE);
     GetRandBytes(ret);
@@ -411,9 +411,9 @@ void CDBIterator::Next() { m_impl_iter->iter->Next(); }
 
 namespace dbwrapper_private {
 
-const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w)
+const std::vector<unsigned char>& GetObfuscation(const CDBWrapper &w)
 {
-    return w.obfuscate_key;
+    return w.m_obfuscation;
 }
 
 } // namespace dbwrapper_private

src/dbwrapper.h

@@ -63,7 +63,7 @@ namespace dbwrapper_private {
  * Database obfuscation should be considered an implementation detail of the
  * specific database.
  */
-const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w);
+const std::vector<unsigned char>& GetObfuscation(const CDBWrapper &w);
 
 }; // namespace dbwrapper_private
 
@@ -166,7 +166,7 @@ class CDBIterator
     template<typename V> bool GetValue(V& value) {
         try {
             DataStream ssValue{GetValueImpl()};
-            ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
+            ssValue.Xor(dbwrapper_private::GetObfuscation(parent));
             ssValue >> value;
         } catch (const std::exception&) {
             return false;
@@ -179,7 +179,7 @@ struct LevelDBContext;
 
 class CDBWrapper
 {
-    friend const std::vector<unsigned char>& dbwrapper_private::GetObfuscateKey(const CDBWrapper &w);
+    friend const std::vector<unsigned char>& dbwrapper_private::GetObfuscation(const CDBWrapper &w);
 private:
     //! holds all leveldb-specific fields of this class
     std::unique_ptr<LevelDBContext> m_db_context;
@@ -188,12 +188,12 @@ class CDBWrapper
     std::string m_name;
 
     //! a key used for optional XOR-obfuscation of the database
-    std::vector<unsigned char> obfuscate_key;
+    std::vector<unsigned char> m_obfuscation;
 
     //! the key under which the obfuscation key is stored
-    static const std::string OBFUSCATE_KEY_KEY;
+    static const std::string OBFUSCATION_KEY_KEY;
 
-    std::vector<unsigned char> CreateObfuscateKey() const;
+    std::vector<unsigned char> CreateObfuscation() const;
 
     //! path to filesystem storage
     const fs::path m_path;
@@ -225,7 +225,7 @@ class CDBWrapper
         }
         try {
             DataStream ssValue{MakeByteSpan(*strValue)};
-            ssValue.Xor(obfuscate_key);
+            ssValue.Xor(m_obfuscation);
             ssValue >> value;
         } catch (const std::exception&) {
             return false;

src/node/blockstorage.cpp

@@ -780,13 +780,13 @@ void BlockManager::UnlinkPrunedFiles(const std::set<int>& setFilesToPrune) const
 
 AutoFile BlockManager::OpenBlockFile(const FlatFilePos& pos, bool fReadOnly) const
 {
-    return AutoFile{m_block_file_seq.Open(pos, fReadOnly), m_xor_key};
+    return AutoFile{m_block_file_seq.Open(pos, fReadOnly), m_obfuscation};
 }
 
 /** Open an undo file (rev?????.dat) */
 AutoFile BlockManager::OpenUndoFile(const FlatFilePos& pos, bool fReadOnly) const
 {
-    return AutoFile{m_undo_file_seq.Open(pos, fReadOnly), m_xor_key};
+    return AutoFile{m_undo_file_seq.Open(pos, fReadOnly), m_obfuscation};
 }
 
 fs::path BlockManager::GetBlockPosFilename(const FlatFilePos& pos) const
@@ -1124,7 +1124,7 @@ static auto InitBlocksdirXorKey(const BlockManager::Options& opts)
 {
     // Bytes are serialized without length indicator, so this is also the exact
     // size of the XOR-key file.
-    std::array<std::byte, Obfuscation::KEY_SIZE> xor_key{};
+    std::array<std::byte, Obfuscation::KEY_SIZE> obfuscation{};
 
     // Consider this to be the first run if the blocksdir contains only hidden
     // files (those which start with a .). Checking for a fully-empty dir would
@@ -1141,14 +1141,14 @@ static auto InitBlocksdirXorKey(const BlockManager::Options& opts)
     if (opts.use_xor && first_run) {
         // Only use random fresh key when the boolean option is set and on the
         // very first start of the program.
-        FastRandomContext{}.fillrand(xor_key);
+        FastRandomContext{}.fillrand(obfuscation);
     }
 
     const fs::path xor_key_path{opts.blocks_dir / "xor.dat"};
     if (fs::exists(xor_key_path)) {
         // A pre-existing xor key file has priority.
         AutoFile xor_key_file{fsbridge::fopen(xor_key_path, "rb")};
-        xor_key_file >> xor_key;
+        xor_key_file >> obfuscation;
     } else {
         // Create initial or missing xor key file
         AutoFile xor_key_file{fsbridge::fopen(xor_key_path,
@@ -1158,28 +1158,28 @@ static auto InitBlocksdirXorKey(const BlockManager::Options& opts)
             "wbx"
 #endif
         )};
-        xor_key_file << xor_key;
+        xor_key_file << obfuscation;
         if (xor_key_file.fclose() != 0) {
             throw std::runtime_error{strprintf("Error closing XOR key file %s: %s",
                                                fs::PathToString(xor_key_path),
                                                SysErrorString(errno))};
         }
     }
     // If the user disabled the key, it must be zero.
-    if (!opts.use_xor && xor_key != decltype(xor_key){}) {
+    if (!opts.use_xor && obfuscation != decltype(obfuscation){}) {
         throw std::runtime_error{
             strprintf("The blocksdir XOR-key can not be disabled when a random key was already stored! "
                       "Stored key: '%s', stored path: '%s'.",
-                      HexStr(xor_key), fs::PathToString(xor_key_path)),
+                      HexStr(obfuscation), fs::PathToString(xor_key_path)),
         };
     }
-    LogInfo("Using obfuscation key for blocksdir *.dat files (%s): '%s'\n", fs::PathToString(opts.blocks_dir), HexStr(xor_key));
-    return std::vector<std::byte>{xor_key.begin(), xor_key.end()};
+    LogInfo("Using obfuscation key for blocksdir *.dat files (%s): '%s'\n", fs::PathToString(opts.blocks_dir), HexStr(obfuscation));
+    return std::vector<std::byte>{obfuscation.begin(), obfuscation.end()};
 }
 
 BlockManager::BlockManager(const util::SignalInterrupt& interrupt, Options opts)
     : m_prune_mode{opts.prune_target > 0},
-      m_xor_key{InitBlocksdirXorKey(opts)},
+      m_obfuscation{InitBlocksdirXorKey(opts)},
       m_opts{std::move(opts)},
       m_block_file_seq{FlatFileSeq{m_opts.blocks_dir, "blk", m_opts.fast_prune ? 0x4000 /* 16kB */ : BLOCKFILE_CHUNK_SIZE}},
       m_undo_file_seq{FlatFileSeq{m_opts.blocks_dir, "rev", UNDOFILE_CHUNK_SIZE}},

src/node/blockstorage.h

@@ -235,7 +235,7 @@ class BlockManager
 
     const bool m_prune_mode;
 
-    const std::vector<std::byte> m_xor_key;
+    const std::vector<std::byte> m_obfuscation;
 
     /** Dirty block index entries. */
     std::set<CBlockIndex*> m_dirty_blockindex;

src/node/mempool_persist.cpp

@@ -60,15 +60,15 @@ bool LoadMempool(CTxMemPool& pool, const fs::path& load_path, Chainstate& active
     try {
         uint64_t version;
         file >> version;
-        std::vector<std::byte> xor_key;
+        std::vector<std::byte> obfuscation;
         if (version == MEMPOOL_DUMP_VERSION_NO_XOR_KEY) {
             // Leave XOR-key empty
         } else if (version == MEMPOOL_DUMP_VERSION) {
-            file >> xor_key;
+            file >> obfuscation;
         } else {
             return false;
         }
-        file.SetXor(xor_key);
+        file.SetObfuscation(obfuscation);
         uint64_t total_txns_to_load;
         file >> total_txns_to_load;
         uint64_t txns_tried = 0;
@@ -180,12 +180,12 @@ bool DumpMempool(const CTxMemPool& pool, const fs::path& dump_path, FopenFn mock
         const uint64_t version{pool.m_opts.persist_v1_dat ? MEMPOOL_DUMP_VERSION_NO_XOR_KEY : MEMPOOL_DUMP_VERSION};
         file << version;
 
-        std::vector<std::byte> xor_key(Obfuscation::KEY_SIZE);
+        std::vector<std::byte> obfuscation(Obfuscation::KEY_SIZE);
         if (!pool.m_opts.persist_v1_dat) {
-            FastRandomContext{}.fillrand(xor_key);
-            file << xor_key;
+            FastRandomContext{}.fillrand(obfuscation);
+            file << obfuscation;
         }
-        file.SetXor(xor_key);
+        file.SetObfuscation(obfuscation);
 
         uint64_t mempool_transactions_to_write(vinfo.size());
         file << mempool_transactions_to_write;

src/streams.cpp

@@ -9,8 +9,8 @@
 
 #include <array>
 
-AutoFile::AutoFile(std::FILE* file, std::vector<std::byte> data_xor)
-    : m_file{file}, m_xor{std::move(data_xor)}
+AutoFile::AutoFile(std::FILE* file, std::vector<std::byte> obfuscation)
+    : m_file{file}, m_obfuscation{std::move(obfuscation)}
 {
     if (!IsNull()) {
         auto pos{std::ftell(m_file)};
@@ -22,9 +22,9 @@ std::size_t AutoFile::detail_fread(std::span<std::byte> dst)
 {
     if (!m_file) throw std::ios_base::failure("AutoFile::read: file handle is nullptr");
     size_t ret = std::fread(dst.data(), 1, dst.size(), m_file);
-    if (!m_xor.empty()) {
+    if (!m_obfuscation.empty()) {
         if (!m_position.has_value()) throw std::ios_base::failure("AutoFile::read: position unknown");
-        util::Xor(dst.subspan(0, ret), m_xor, *m_position);
+        util::Xor(dst.subspan(0, ret), m_obfuscation, *m_position);
     }
     if (m_position.has_value()) *m_position += ret;
     return ret;
@@ -81,7 +81,7 @@ void AutoFile::ignore(size_t nSize)
 void AutoFile::write(std::span<const std::byte> src)
 {
     if (!m_file) throw std::ios_base::failure("AutoFile::write: file handle is nullptr");
-    if (m_xor.empty()) {
+    if (m_obfuscation.empty()) {
         if (std::fwrite(src.data(), 1, src.size(), m_file) != src.size()) {
             throw std::ios_base::failure("AutoFile::write: write failed");
         }
@@ -101,9 +101,9 @@ void AutoFile::write(std::span<const std::byte> src)
 void AutoFile::write_buffer(std::span<std::byte> src)
 {
     if (!m_file) throw std::ios_base::failure("AutoFile::write_buffer: file handle is nullptr");
-    if (m_xor.size()) {
+    if (m_obfuscation.size()) {
         if (!m_position) throw std::ios_base::failure("AutoFile::write_buffer: obfuscation position unknown");
-        util::Xor(src, m_xor, *m_position); // obfuscate in-place
+        util::Xor(src, m_obfuscation, *m_position); // obfuscate in-place
     }
     if (std::fwrite(src.data(), 1, src.size(), m_file) != src.size()) {
         throw std::ios_base::failure("AutoFile::write_buffer: write failed");

src/streams.h

@@ -402,12 +402,12 @@ class AutoFile
 {
 protected:
     std::FILE* m_file;
-    std::vector<std::byte> m_xor;
+    std::vector<std::byte> m_obfuscation;
     std::optional<int64_t> m_position;
     bool m_was_written{false};
 
 public:
-    explicit AutoFile(std::FILE* file, std::vector<std::byte> data_xor={});
+    explicit AutoFile(std::FILE* file, std::vector<std::byte> obfuscation={});
 
     ~AutoFile()
     {
@@ -455,7 +455,7 @@ class AutoFile
     bool IsNull() const { return m_file == nullptr; }
 
     /** Continue with a different XOR key */
-    void SetXor(std::vector<std::byte> data_xor) { m_xor = data_xor; }
+    void SetObfuscation(std::vector<std::byte> obfuscation) { m_obfuscation = obfuscation; }
 
     /** Implementation detail, only used internally. */
     std::size_t detail_fread(std::span<std::byte> dst);

src/test/dbwrapper_tests.cpp

@@ -42,7 +42,7 @@ BOOST_AUTO_TEST_CASE(dbwrapper)
             BOOST_CHECK_EQUAL(obfuscate, !dbw.IsEmpty());
 
             // Ensure that we're doing real obfuscation when obfuscate=true
-            obfuscation_key = dbwrapper_private::GetObfuscateKey(dbw);
+            obfuscation_key = dbwrapper_private::GetObfuscation(dbw);
             BOOST_CHECK_EQUAL(obfuscate, !is_null_key(obfuscation_key));
 
             for (uint8_t k{0}; k < 10; ++k) {
@@ -56,15 +56,15 @@ BOOST_AUTO_TEST_CASE(dbwrapper)
         // Verify that the obfuscation key is never obfuscated
         {
             CDBWrapper dbw{{.path = path, .cache_bytes = CACHE_SIZE, .obfuscate = false}};
-            BOOST_CHECK(obfuscation_key == dbwrapper_private::GetObfuscateKey(dbw));
+            BOOST_CHECK(obfuscation_key == dbwrapper_private::GetObfuscation(dbw));
         }
 
         // Read back the values
         {
             CDBWrapper dbw{{.path = path, .cache_bytes = CACHE_SIZE, .obfuscate = obfuscate}};
 
             // Ensure obfuscation is read back correctly
-            BOOST_CHECK(obfuscation_key == dbwrapper_private::GetObfuscateKey(dbw));
+            BOOST_CHECK(obfuscation_key == dbwrapper_private::GetObfuscation(dbw));
             BOOST_CHECK_EQUAL(obfuscate, !is_null_key(obfuscation_key));
 
             // Verify all written values
@@ -89,7 +89,7 @@ BOOST_AUTO_TEST_CASE(dbwrapper_basic_data)
         bool res_bool;
 
         // Ensure that we're doing real obfuscation when obfuscate=true
-        BOOST_CHECK_EQUAL(obfuscate, !is_null_key(dbwrapper_private::GetObfuscateKey(dbw)));
+        BOOST_CHECK_EQUAL(obfuscate, !is_null_key(dbwrapper_private::GetObfuscation(dbw)));
 
         //Simulate block raw data - "b + block hash"
         std::string key_block = "b" + m_rng.rand256().ToString();
@@ -264,7 +264,7 @@ BOOST_AUTO_TEST_CASE(existing_data_no_obfuscate)
     BOOST_CHECK_EQUAL(res2.ToString(), in.ToString());
 
     BOOST_CHECK(!odbw.IsEmpty());
-    BOOST_CHECK(is_null_key(dbwrapper_private::GetObfuscateKey(odbw))); // The key should be an empty string
+    BOOST_CHECK(is_null_key(dbwrapper_private::GetObfuscation(odbw))); // The key should be an empty string
 
     uint256 in2 = m_rng.rand256();
     uint256 res3;
@@ -301,7 +301,7 @@ BOOST_AUTO_TEST_CASE(existing_data_reindex)
     // Check that the key/val we wrote with unobfuscated wrapper doesn't exist
     uint256 res2;
     BOOST_CHECK(!odbw.Read(key, res2));
-    BOOST_CHECK(!is_null_key(dbwrapper_private::GetObfuscateKey(odbw)));
+    BOOST_CHECK(!is_null_key(dbwrapper_private::GetObfuscation(odbw)));
 
     uint256 in2 = m_rng.rand256();
     uint256 res3;