Hypatia/README.md

Hypatia

Overview

Hypatia is the worlds first FOSS malware scanner for Android. It is powered by ClamAV signature databases (GPLv3).

Features

• Near zero battery impact: you'll never notice any impact on battery at all
• Extremely fast: it can scan small files (1MB) in <20ms, and even large files (40MB) in 1000ms.
• Memory efficient: with the default databases enabled it uses under 120MB.
• Regular scan: allowing selection of /system, internal storage, external storage, and installed apps
• Realtime scanner: can detect malware in realtime on write/rename in internal storage
• Completely offline: Internet is only used to download signature databases, files will never ever leave your device
• Persistence: will automatically restart on boot/update
• Tiny codebase: coming in at under 1000 sloc, it can be audited by even someone with basic programming experience
• Minimal dependencies: the app only uses libraries when necessary
• Signature databases can be enabled/disabled at the users demand

Technical Details

• Signature databases are ClavAV .hdb (MD5 hashes) and .hsb (SHA-1/SHA-256) format
• Signature databases will not be redownloaded if the file hasn't changed on the server (304 not modified)
• Signatures are stored using HashMaps for O(1) lookup
• Files have their MD5/SHA-1/SHA-256 hashes calculated in one pass
• Realtime scanner is multithreaded and will use half of the device's core count for scanning multiple files asynchronously
• Realtime scanning powered by a recursive FileObserver

Planned Updates

• Option to scan on access
• Option to quarantine/delete on detection
• Scan files via share intent
• Scan newly installed/updated apps
• Better GUI
• Translations
• Scanning entire system using root (low priority)

Goals

• Be fast
• Don't eat batteries
• Use minimal permissions
• Use libraries only when necessary

Credits

• RecursiveFileObserver.java (GPLv3): Daniel Gultsch, ownCloud Inc., Bartek Przybylski
• Icons (Apache-2.0): Google/Android/AOSP