HTTP Sniffer

This is a professional-grade network packet capture and debugging tool for mobile developers and testers, providing comprehensive real-time traffic monitoring, multi-protocol analysis, and debugging capabilities for Android apps.

### Core Capabilities

- **Multi-Protocol Capture**: Real-time capture and analysis of HTTP/HTTPS, WebSocket (WS/WSS), DNS, SSE, gRPC (Unary/Stream), and MQTT protocols.

- **Analysis by Application**: Filters and analyzes network traffic by application to quickly locate the source of problems.

- **HTTPS Decryption**: Provides SSL/TLS certificate management and import, and supports encrypted traffic decryption analysis.

- **Traffic Redirect**: Redirect all captured TCP/UDP connections to a specified server for remote debugging and traffic inspection.

- **HTTP Webhook**: Forward captured packets to custom POST endpoints for integration with external tools and monitoring systems.

- **Request Simulation (Mock)**: Configurable rules allow for HTTP mocking, facilitating both online and offline debugging.

- **Modify and Replay**: Supports editing requests and responses after interception, and replays to verify the effectiveness of repairs.

### Why Use VPNService

Apps use Android's VPNService to implement system-level network data channels, enabling the following capabilities:

- **Network Interception**: Intercepts network requests and responses from other apps on the device using VPN technology.

- **Packet Analysis**: Analyze HTTP, WebSocket, gRPC, DNS, and MQTT traffic in real time, extracting and displaying key fields and data.

- **Network Debugging**: Provides request path tracing, performance observation, and problem location tools to assist in development and debugging.

- **Packet Rewriting**: Modifies intercepted requests, injects rules, and resends them to verify remediation solutions.

### Compliance and Transparency Statement

- **User Perception**: Continuously displays the VPN service status in the notification bar to ensure users are fully informed.

- **Permission Transparency**: Clearly explain the reason and purpose of VPN permissions during the authorization and onboarding process.

- **Functional Necessity**: VPNService is a necessary technical means for system-level network interception and analysis.

- **Security Boundary**: Used only for network debugging and analysis in development and testing scenarios; no user privacy data is collected.

- **HTTPS Compliance**: HTTPS decryption is only performed after the user has actively installed a trusted certificate and explicitly authorized it. Certificate management is fully controllable and removable.

### Applicable Scenarios

- Development debugging, API verification, problem reproduction and location

- WebSocket/gRPC/SSE real-time communication debugging

- DNS resolution analysis and MQTT IoT protocol inspection

- Traffic redirect to PC for advanced debugging with Wireshark, Charles, etc.

- Webhook integration for automated monitoring and alerting

- Third-party SDK/embedded WebView network behavior analysis

- Rapidly construct and verify mock scenarios