CoSSH (Cobalt SSH)

CoSSH is a native, highly secure Android SSH terminal client designed to replace legacy applications. It features a cobalt-blue aesthetic, one-touch connectivity, robust hardware-backed local Keystore encryption, and Google Drive cloud sync.

🚀 Features

• Native & Modern: Built entirely with Kotlin and Jetpack Compose for a fluid, responsive Android experience.
• Uncompromising Security:
  • Zero-cleartext volatile state sanitization.
  • Hardware-backed Android Keystore encryption for saved profiles and identities.
  • High-friction Host Key MITM warnings (Trust On First Use).
  • Strict OS-level backup exclusions to protect private keys.
• Robust Terminal: Full PTY emulation with 256-color support, customizable extra keys (Ctrl, Alt, Esc, Tab, F1-F12), and secure background connection persistence.
• Advanced Capabilities:
  • RSA and ED25519 Key Generation and PEM parsing.
  • Port Forwarding (Local & Remote).
  • Legacy Telnet protocol support (with explicit insecurity warnings).
• Cloud Sync (Premium): Securely synchronize your encrypted profiles via Google Drive.

🛠️ Tech Stack

• Language: Kotlin
• UI Framework: Jetpack Compose (Material Design 3)
• Networking: sshj, Apache Commons Net (Telnet)
• Cryptography: BouncyCastle, Android Security Crypto (EncryptedSharedPreferences)
• Terminal Emulation: Termux JNI / Terminal-View

🏗️ Getting Started

Prerequisites

• Android Studio
• JDK 17+

Build Instructions

To build the application locally:

# Clone the repository
git clone https://github.com/adamoutler/cossh.git
cd cossh

# Run local tests and linting
./gradlew test lint

# Build the debug APK
./gradlew assembleDebug

🧪 Testing and QA

CoSSH adheres to strict "Zero-Tolerance Quality" standards.

• Minimum 80% Unit Test coverage is strictly enforced via CI.
• All UI components are verified via Robolectric/Paparazzi snapshot tests.
• Commits are automatically analyzed by SonarCloud for bugs and vulnerabilities.

🔒 Security & Privacy

Security is the paramount invariant of this project. If you discover a vulnerability, please report it immediately. The app intentionally refuses to fall back to insecure storage mechanisms.

• Detailed cryptographic architecture & threat modeling: Security Whitepaper
• Privacy commitments & permission disclosures: Privacy Policy

📄 License

This project is licensed under the terms of the GNU General Public License v3.0 — see the LICENSE file for details.