Initial public release

MCP (Model Context Protocol) server for reading and writing an Obsidian vault, gated by OAuth-issued JWT bearer tokens. See README.md for setup.
2026-05-17 23:53:00 +08:00
commit 515763bc72
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+using Microsoft.AspNetCore.Authorization;
+
+namespace ObsidianMcp.Auth;
+
+/// <summary>
+/// 自定义 scope 校验 Policy：
+///   RequireScope("read:obsidian")
+///   RequireScope("write:obsidian")
+///
+/// JWT 的 scope claim 可能是单个字符串（空格分隔）或多个 claim，两种都处理。
+/// </summary>
+public static class ScopePolicies
+{
+    public const string ReadObsidian = "read:obsidian";
+    public const string WriteObsidian = "write:obsidian";
+
+    /// <summary>注册两条 scope policy 到 AuthorizationOptions。</summary>
+    public static void AddScopePolicies(this AuthorizationOptions opts)
+    {
+        opts.AddPolicy(ReadObsidian, policy =>
+            policy.RequireAuthenticatedUser()
+                  .AddRequirements(new ScopeRequirement(ReadObsidian)));
+
+        opts.AddPolicy(WriteObsidian, policy =>
+            policy.RequireAuthenticatedUser()
+                  .AddRequirements(new ScopeRequirement(WriteObsidian)));
+    }
+}
+
+// ---------- Requirement ----------
+
+public class ScopeRequirement(string scope) : IAuthorizationRequirement
+{
+    public string RequiredScope { get; } = scope;
+}
+
+// ---------- Handler ----------
+
+public class ScopeAuthorizationHandler : AuthorizationHandler<ScopeRequirement>
+{
+    protected override Task HandleRequirementAsync(
+        AuthorizationHandlerContext context,
+        ScopeRequirement requirement)
+    {
+        // scope claim 在 JWT 里可能是一整个空格分隔的字符串，也可能是多个 claim。
+        // OAuth 2.0 (RFC 6749) 规定 scope 大小写敏感，按 Ordinal 比对。
+        var scopes = context.User
+            .FindAll("scope")
+            .SelectMany(c => c.Value.Split(' ', StringSplitOptions.RemoveEmptyEntries))
+            .ToHashSet(StringComparer.Ordinal);
+
+        if (scopes.Contains(requirement.RequiredScope))
+            context.Succeed(requirement);
+
+        return Task.CompletedTask;
+    }
+}
+
+// ---------- Per-tool scope guard helper ----------
+
+/// <summary>
+/// MCP Tool 内部 scope 校验：从当前 HttpContext.User 读 scope claim，
+/// 不包含 requiredScope 时抛 UnauthorizedAccessException。
+///
+/// 用法：在每个读 / 写 Tool 的方法体首行调一下，给客户端可读的失败原因。
+/// 端点级 RequireAuthorization 只确保 JWT 验签通过；scope 颗粒度门禁在这里。
+/// OAuth 2.0 (RFC 6749) 规定 scope 大小写敏感。
+/// </summary>
+public static class ToolScopeGuard
+{
+    public static void EnsureScope(IHttpContextAccessor http, string requiredScope)
+    {
+        var ctx = http.HttpContext
+            ?? throw new InvalidOperationException("无 HttpContext，无法校验 scope。");
+
+        var scopes = ctx.User
+            .FindAll("scope")
+            .SelectMany(c => c.Value.Split(' ', StringSplitOptions.RemoveEmptyEntries))
+            .ToHashSet(StringComparer.Ordinal);
+
+        if (!scopes.Contains(requiredScope))
+            throw new UnauthorizedAccessException(
+                $"当前 Token 缺少所需 scope：{requiredScope}");
+    }
+}