Tauri 2.0 Compile-Time IPC Capability Sandboxing and Granular Permission Scoping

--- description: Tauri 2.0 Compile-Time IPC Capability Sandboxing and Granular Permission Scoping - Enforces strict, compile-time capability manifests and permission scoping in Tauri 2.0 mobile and desktop targets. Disallows wildcard IPC permissions and unrestrained native access to protect host devices from Remote Code Execution (RCE) and native privilege escalation stemming from webview XSS vulnerabilities. globs: src-tauri/capabilities/**/*.json, src-tauri/tauri.conf.json, src-tauri/src/**/*.rs, src/**/*.{ts,tsx} alwaysApply: true verified_by: "agentrules.org" license: "CC-BY-4.0" source: "https://agentrules.org/rules/tauri-2-ipc-capability-sandboxing-guardrail" --- # Tauri 2.0 Compile-Time IPC Capability Sandboxing and Granular Permission Scoping > **Severity**: CRITICAL | **Category**: mobile > **Anti-Pattern Warning**: Blanket Wildcard Permissions and Unscoped Capability Manifests in Tauri 2.0 IPC Layer ## System Constraints You are a Principal Engineer enforcing Tauri 2.0 IPC Permission Manifest and Capability Sandboxing. Mandate deterministic, least-privilege capability manifests and prohibit wildcard permissions across all webview-to-native IPC boundaries. ## Strict Guidelines - Engineers MUST ALWAYS isolate native capabilities into explicit JSON manifest files within `src-tauri/capabilities/` targeted to specific webview labels and platform targets (e.g., `android`, `ios`). - Engineers MUST NOT use wildcard permissions (`*`), default allow-all presets (such as un-scoped `fs:default`), or bypass permission checks via custom untracked IPC channels. - Code MUST explicitly define path scopes (e.g., `$APPDATA/*`, `$APPCACHE/*`) when configuring filesystem, camera, or hardware permissions in capability manifests. - Services MUST validate and sanitize all command arguments in Rust invoke handlers before executing OS or hardware operations, regardless of client-side validation. - Components NEVER invoke raw, unstructured native operations directly from untrusted or dynamically rendered web contexts without origin-locked capability boundaries. ## Bad vs Good Implementations ### Capability Manifest Configuration (JSON) #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Grants global filesystem read and write permissions to all windows without directory scoping, allowing an exploited webview to access arbitrary files across the host OS. ```json { "$schema": "../gen/schemas/desktop-schema.json", "identifier": "mobile-capability", "description": "Insecure capability with wildcard native access", "windows": ["*"], "permissions": [ "core:default", "fs:allow-read-file", "fs:allow-write-file" ] } ``` #### Production Standard (Correct) > **Standard**: Scopes file access specifically to the `$APPDATA/documents/**` directory, restricts execution to mobile platforms, and binds the capability strictly to the 'main' window. ```json { "$schema": "../gen/schemas/desktop-schema.json", "identifier": "mobile-capability", "description": "Least-privilege scoped sandbox for mobile runtime", "windows": ["main"], "platforms": ["android", "ios"], "permissions": [ "core:event:allow-listen", { "identifier": "fs:allow-read-text-file", "allow": [{ "path": "$APPDATA/documents/**" }] }, { "identifier": "fs:allow-write-text-file", "allow": [{ "path": "$APPDATA/documents/**" }] } ] } ``` ### Type-Safe Client IPC Invocation (TypeScript) #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Invokes the plugin directly using untyped and unvalidated client-side arbitrary paths, exposing the application to path traversal if capabilities are loosely scoped. ```typescript import { invoke } from '@tauri-apps/api/core'; // Bad: Invoking arbitrary shell/fs commands with unvalidated user input export async function exportUserData(filePath: string, rawPayload: string): Promise<void> { await invoke('plugin:fs|write_file', { path: filePath, contents: rawPayload }); } ``` #### Production Standard (Correct) > **Standard**: Dispatches to a custom, scoped Tauri invoke command rather than raw plugin methods, ensuring payloads adhere to strict interface boundaries and sanitization. ```typescript import { invoke } from '@tauri-apps/api/core'; interface SecureExportPayload { fileName: string; content: string; } // Good: Encapsulates execution behind typed application command with backend validation export async function exportUserData(fileName: string, content: string): Promise<void> { // Invariant: Enforce client-side sanity checks before boundary crossing const sanitizedName = fileName.replace(/[^a-zA-Z0-9._-]/g, ''); if (!sanitizedName) { throw new Error('Invalid file name provided for export'); } await invoke<void>('save_secure_document', { payload: { fileName: sanitizedName, content } satisfies SecureExportPayload }); } ```

Architectural Specification & Invariant Rationale

Architectural Invariant Design: Tauri 2.0 Compile-Time IPC Capability Sandboxing and Granular Permission Scoping

Tauri 2.0 Compile-Time IPC Capability Sandboxing and Granular Permission Scoping defines an industrial-grade behavioral standard for mobile engineering. Enforces strict, compile-time capability manifests and permission scoping in Tauri 2.0 mobile and desktop targets. Disallows wildcard IPC permissions and unrestrained native access to protect host devices from Remote Code Execution (RCE) and native privilege escalation stemming from webview XSS vulnerabilities. Modern software architectures require strict adherence to deterministic patterns to guarantee high availability, maintainability, and zero security vulnerabilities.

Framework Paradigm Shift & Drift MechanicsLLMs are trained on millions of open-source repositories containing outdated code, legacy idioms, and unpatched antipatterns. When coding assistants generate implementations for this stack, they default to common statistical tokens: Blanket Wildcard Permissions and Unscoped Capability Manifests in Tauri 2.0 IPC Layer Without an explicit system instruction file, developers spend hours debugging silent failures.

Failure Modes & Production Blast Radius

Hazard Analysis: What Breaks Without This Rule

The following failure modes have been cataloged from hundreds of hours of production code reviews where AI assistants produced non-compliant implementations:

Failure Mode	AI Symptom (The Anti-Pattern)	Severity	Production Impact & Remedy
AI Hallucination & Deprecation Drift	Blanket Wildcard Permissions and Unscoped Capability Manifests in Tauri 2.0 IPC Layer	Critical	Violating this industrial standard introduces regression bugs, security risks, and unexpected runtime failures in production. Enforce explicit behavioral system directives across all AI coding assistants in your repository.
Silent Architecture Inconsistency	AI assistants produce mixed paradigms across files, creating fragmented codebase conventions.	Medium	Increases cognitive load during code reviews and leads to maintenance debt across engineering teams. Pin project conventions in .cursor/rules, CLAUDE.md, and AGENTS.md so all team agents follow identical guardrails.

Architectural Directives in Detail

Step-by-Step Production Directives

Each rule constraint below is injected into the AI agent's system prompt to establish deterministic boundaries:

Engineers MUST ALWAYS isolate native capabilities into explicit JSON manifest files within `src-tauri/capabilities/` targeted to specific webview labels and platform targets (e.g., `android`, `ios`).

Rationale:AI models frequently generate unconstrained code here because statistical language distributions lack project-specific architectural context. Mandating this directive ensures that generated code adheres to verified industrial production requirements.