初始化奇妙小屏幕控制器项目

2026-09-08 22:56:52 +08:00
commit 8d368de3b5
491 changed files with 67678 additions and 0 deletions
@@ -0,0 +1,113 @@
+using System.Security.Cryptography;
+using System.Text;
+
+namespace MatrixImageEditor;
+
+public static class ImageOperations
+{
+    private static readonly UTF8Encoding Utf8NoBomStrict = new(encoderShouldEmitUTF8Identifier: false, throwOnInvalidBytes: true);
+
+    public static ImageConfig ReadConfig(string imagePath)
+    {
+        imagePath = ImagePathRules.ValidateExistingImage(imagePath);
+        VerifySidecarIfPresent(imagePath);
+        using var disk = new Fat16Disk(imagePath, writable: false);
+        return ImageConfigCodec.Read(disk.ReadFile("MSCCFG.BIN"));
+    }
+
+    public static void WriteConfig(string imagePath, ImageConfig config)
+    {
+        imagePath = ImagePathRules.ValidateExistingImage(imagePath);
+        VerifySidecarIfPresent(imagePath);
+        using var disk = new Fat16Disk(imagePath, writable: true);
+        var current = disk.ReadFile("MSCCFG.BIN");
+        if (ImageConfigCodec.Read(current).SoftwareVersion != config.SoftwareVersion) throw new InvalidDataException("禁止通过编辑器改变软件版本");
+        var update = ImageConfigCodec.EncodeUpdate(current, config);
+        disk.WriteFileRange("MSCCFG.BIN", ImageConfigCodec.SlotOffset(update.TargetSlot), update.SlotData);
+        var verified = ImageConfigCodec.Read(disk.ReadFile("MSCCFG.BIN"));
+        if (!ImageConfigCodec.Serialize(verified).Equals(ImageConfigCodec.Serialize(config), StringComparison.Ordinal)) throw new IOException("配置写后校验失败");
+    }
+
+    public static void WriteSha256(string imagePath, IProgress<int>? progress)
+    {
+        imagePath = ImagePathRules.ValidateExistingImage(imagePath);
+        using var stream = new FileStream(imagePath, FileMode.Open, FileAccess.Read, FileShare.Read, 4 * 1024 * 1024, FileOptions.SequentialScan);
+        using var hash = IncrementalHash.CreateHash(HashAlgorithmName.SHA256);
+        var buffer = new byte[4 * 1024 * 1024];
+        long completed = 0;
+        int read;
+        while ((read = stream.Read(buffer, 0, buffer.Length)) > 0)
+        {
+            hash.AppendData(buffer, 0, read);
+            completed += read;
+            progress?.Report((int)(completed * 100 / stream.Length));
+        }
+        var digest = Convert.ToHexString(hash.GetHashAndReset()).ToLowerInvariant();
+        progress?.Report(100);
+
+        var sidecar = imagePath + ".sha256";
+        var temporary = sidecar + "." + Guid.NewGuid().ToString("N") + ".tmp";
+        try
+        {
+            var bytes = Utf8NoBomStrict.GetBytes($"{digest}  {Path.GetFileName(imagePath)}\n");
+            using (var output = new FileStream(temporary, FileMode.CreateNew, FileAccess.Write, FileShare.None, 4096, FileOptions.WriteThrough))
+            {
+                output.Write(bytes);
+                output.Flush(flushToDisk: true);
+            }
+            File.Move(temporary, sidecar, overwrite: true);
+            var stored = ReadSidecarDigest(sidecar, Path.GetFileName(imagePath));
+            if (!stored.Equals(digest, StringComparison.Ordinal)) throw new IOException("镜像 SHA-256 摘要写后校验失败");
+        }
+        finally
+        {
+            if (File.Exists(temporary)) File.Delete(temporary);
+        }
+    }
+
+    private static void VerifySidecarIfPresent(string imagePath)
+    {
+        var sidecar = imagePath + ".sha256";
+        if (!File.Exists(sidecar)) return;
+        var expected = ReadSidecarDigest(sidecar, Path.GetFileName(imagePath));
+        using var stream = new FileStream(imagePath, FileMode.Open, FileAccess.Read, FileShare.Read, 4 * 1024 * 1024, FileOptions.SequentialScan);
+        var actual = Convert.ToHexString(SHA256.HashData(stream)).ToLowerInvariant();
+        if (!actual.Equals(expected, StringComparison.Ordinal)) throw new InvalidDataException("镜像内容与 SHA-256 摘要不符，禁止编辑");
+    }
+
+    private static string ReadSidecarDigest(string sidecarPath, string expectedFileName)
+    {
+        if (new FileInfo(sidecarPath).Length > 128 * 1024) throw new InvalidDataException("镜像 SHA-256 摘要文件过大");
+        var bytes = File.ReadAllBytes(sidecarPath);
+        if (bytes.Length >= 3 && bytes[0] == 0xEF && bytes[1] == 0xBB && bytes[2] == 0xBF) throw new InvalidDataException("镜像 SHA-256 摘要必须使用无 BOM UTF-8 格式");
+
+        string content;
+        try
+        {
+            content = Utf8NoBomStrict.GetString(bytes);
+        }
+        catch (DecoderFallbackException exception)
+        {
+            throw new InvalidDataException("镜像 SHA-256 摘要不是有效的 UTF-8 文本", exception);
+        }
+
+        if (content.Length < 68 || content[^1] != '\n' || content.AsSpan(0, content.Length - 1).ContainsAny('\r', '\n'))
+        {
+            throw new InvalidDataException("镜像 SHA-256 摘要文件必须是以 LF 结尾的单行规范格式");
+        }
+
+        var line = content.AsSpan(0, content.Length - 1);
+        var digest = line[..64];
+        if (digest.ContainsAnyExcept("0123456789abcdef") || line[64] != ' ' || line[65] != ' ')
+        {
+            throw new InvalidDataException("镜像 SHA-256 摘要文件格式无效");
+        }
+
+        var storedFileName = line[66..].ToString();
+        if (!storedFileName.Equals(expectedFileName, StringComparison.Ordinal))
+        {
+            throw new InvalidDataException("镜像 SHA-256 摘要中的文件名与当前镜像不一致");
+        }
+        return digest.ToString();
+    }
+}