Tauri 2.0 Fine-Grained IPC Capability Manifest & Window Isolation Standard

--- description: Tauri 2.0 Fine-Grained IPC Capability Manifest & Window Isolation Standard - Enforces fine-grained permission capabilities and explicit window-to-command isolation in Tauri 2.0 configurations. Prevents arbitrary remote code execution and local privilege escalation across iOS, Android, and desktop by ensuring webviews only access explicitly scoped, cryptographically pinned IPC commands and secure origin sets. globs: src-tauri/capabilities/**/*.json, src-tauri/capabilities/**/*.toml, src-tauri/tauri.conf.json, src-tauri/src/main.rs, src-tauri/src/lib.rs, src/**/*.{ts,tsx} alwaysApply: true verified_by: "agentrules.org" license: "CC-BY-4.0" source: "https://agentrules.org/rules/tauri-v2-ipc-capability-manifest-standard" --- # Tauri 2.0 Fine-Grained IPC Capability Manifest & Window Isolation Standard > **Severity**: CRITICAL | **Category**: mobile > **Anti-Pattern Warning**: Wildcard Permissions and Global IPC Command Exposure Across Unrestricted Webviews ## System Constraints You are a Principal Engineer and Security Architect enforcing the Tauri 2.0 Fine-Grained IPC Capability Manifest Standard. You must mandate strict least-privilege IPC capabilities across mobile and desktop targets, ensuring that webviews cannot invoke unauthorized native Rust commands or access global capabilities through wildcard declarations or improper origin mappings. ## Strict Guidelines - Engineers MUST ALWAYS isolate distinct webviews into dedicated capability files under `src-tauri/capabilities/` with explicit window bindings. - Engineers MUST NOT use wildcard permissions (`*:*` or `core:*`) or bind global capabilities to external remote URLs in `tauri.conf.json` or capability JSON manifests. - Security manifests MUST restrict filesystem, shell, and native OS plugins to explicitly scoped paths using permission parameters rather than granting root access. - Mobile-specific capabilities (camera, geolocation, biometrics, notification) MUST be mapped strictly to authorized mobile webview windows or label patterns. - Frontend IPC invokers MUST validate payload schemas using Zod or equivalent runtime validators before calling `invoke()` to ensure command contract parity. ## Bad vs Good Implementations ### Tauri 2.0 Capability Manifest Definition #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Using wildcard window bindings ('*') combined with unconstrained permissions ('shell:allow-execute', 'fs:default') exposes full native shell and filesystem execution to any compromised webview or external frame. ```json { "$schema": "../gen/schemas/desktop-schema.json", "identifier": "default-capability", "description": "Insecure global capability granting all commands to any window", "windows": ["*"], "permissions": [ "core:default", "shell:allow-execute", "fs:default" ] } ``` #### Production Standard (Correct) > **Standard**: Binds specific permissions exclusively to designated windows ('main', 'auth-webview') and scopes the filesystem permission to a specific non-traversable application data subdirectory without shell access. ```json { "$schema": "../gen/schemas/mobile-schema.json", "identifier": "mobile-auth-capability", "description": "Scoped capability for authentication window on mobile and desktop", "windows": ["main", "auth-webview"], "permissions": [ "core:event:allow-listen", "core:event:allow-emit", { "identifier": "fs:allow-read-text-file", "allow": [{ "path": "$APPDATA/tokens/*" }] }, "biometric:allow-authenticate" ] } ``` ### Client-Side Type-Safe IPC Invocation with Runtime Validation #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Lacks payload validation and defensive error handling, allowing prototype pollution or corrupted parameters to traverse IPC boundaries unhindered. ```typescript import { invoke } from '@tauri-apps/api/core'; // Flawed: Unchecked payload sent via raw invoke without validation or error containment export async function executeUserPayment(data: any): Promise<void> { await invoke('process_payment', { payload: data }); } ``` #### Production Standard (Correct) > **Standard**: Validates the command payload strictly at runtime before sending it across the IPC bridge, ensuring only structural contract-compliant data reaches the native Rust command. ```typescript import { invoke } from '@tauri-apps/api/core'; import { z } from 'zod'; const PaymentPayloadSchema = z.object({ transactionId: z.string().uuid(), amountInCents: z.number().int().positive(), currency: z.enum(['USD', 'EUR', 'GBP']) }); export type PaymentPayload = z.infer<typeof PaymentPayloadSchema>; export async function executeUserPayment(raw: unknown): Promise<void> { const payload = PaymentPayloadSchema.parse(raw); try { await invoke<void>('process_payment', { payload }); } catch (error: unknown) { throw new Error(`Secure IPC 'process_payment' rejected: ${String(error)}`); } } ```

Architectural Specification & Invariant Rationale

Architectural Invariant Design: Tauri 2.0 Fine-Grained IPC Capability Manifest & Window Isolation Standard

Tauri 2.0 Fine-Grained IPC Capability Manifest & Window Isolation Standard defines an industrial-grade behavioral standard for mobile engineering. Enforces fine-grained permission capabilities and explicit window-to-command isolation in Tauri 2.0 configurations. Prevents arbitrary remote code execution and local privilege escalation across iOS, Android, and desktop by ensuring webviews only access explicitly scoped, cryptographically pinned IPC commands and secure origin sets. 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: Wildcard Permissions and Global IPC Command Exposure Across Unrestricted Webviews 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	Wildcard Permissions and Global IPC Command Exposure Across Unrestricted Webviews	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 distinct webviews into dedicated capability files under `src-tauri/capabilities/` with explicit window bindings.

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.