google/google-authenticatorArchived
Google Authenticator
This is a two-factor authentication library and open-source multi-factor authentication implementation. It provides a suite of tools for implementing security workflows that require a second layer of verification beyond standard credentials.
The project implements both time-based one-time passwords and HMAC-based one-time passwords. It includes utilities for generating these codes based on shared secrets and counters, following industry standards such as RFC 6238.
The library covers cryptographic primitives including Base32 secret key encoding, dynamic truncation extraction, and symmetric key secret storage. These capabilities enable the creation and validation of passcodes for two-step verification systems.
Features
- Multi-Factor Authentication - Provides a complete implementation for adding multi-factor authentication to secure user login processes.
- TOTP Authentication Systems - Provides a command line utility for generating RFC 6238 compliant time-based one-time passwords.
- Dynamic Truncation Utilities - Provides the dynamic truncation logic necessary to convert HMAC hashes into six-digit authentication codes.
- One-Time Passwords - Implements HMAC-based one-time password generation using shared secrets and incrementing counters.
- OTP Generators - Provides a tool for creating HMAC-based one-time passwords for secure user verification.
- TOTP Generation Utilities - Implements utilities for generating time-based one-time passwords from stored secrets.
- Two-Factor Authentication - Offers a library of tools for implementing two-factor authentication using standard TOTP and HOTP algorithms.
- Two-Step Login Flows - Facilitates the implementation of two-step verification flows to protect accounts from unauthorized access.
- MFA Implementations - Serves as an open-source reference implementation of the one-time password protocol for secondary security layers.
- Symmetric Secret Stores - Provides local storage for symmetric cryptographic keys to enable offline authentication token generation.
- Authentication Tools - Implementation of one-time passcode generators.
