README
¶
falcon – a CLI tool to explore FALCON signatures
This repository introduces the falcon CLI tool, designed to facilitate exploration of the FALCON signature scheme.
This tool is part of the R&D work to make the Algorand blockchain quantum-safe, but it can also be used independently to explore FALCON signatures.
The tool implements the FALCON-1024 scheme, based on this implementation, using deterministic signing (which means signing a message with a given private key will always produce the same signature).
| Key type | Size |
|---|---|
| Public key | 1,793 bytes |
| Private key | 2,305 bytes |
| Signature | 1,538 bytes (uncompressed) |
FALCON-1024 targets NIST security level 5 — i.e., at least as hard to break as brute-forcing AES-256 (~256-bit classical security). That’s the highest NIST Post-Quantum Cryptography category for signatures.
Installation
Install via go install
If you have Go1.21+ installed, you can install directly with:
go install github.com/algorandfoundation/falcon-signatures/cmd/falcon@latest
This places the falcon binary in your Go bin directory (usually $GOBIN or $GOPATH/bin).
Make sure that directory is on your PATH.
Verify installation:
falcon help
Pre-built binaries
Pre-built binaries are available on the releases page
Build from source
You need Go1.25+ to build from source:
git clone https://github.com/algorandfoundation/falcon-signatures.git
cd falcon-signatures
make build
This creates the falcon binary at ./build/falcon.
Run make help to see all available commands.
Usage
Available commands:
| Command | Description |
|---|---|
falcon create |
Create a new keypair |
falcon sign |
Sign a message |
falcon verify |
Verify a signature for a message |
falcon info |
Display information about a keypair file |
falcon version |
Show the CLI build version |
falcon help |
Show help |
falcon algorand |
Algorand-specific commands |
Key Management
falcon create generates keys using 24-word BIP-39 mnemonics by default for easy recovery.
- Default: 256-bit entropy with mnemonic (recoverable)
- High security: 384-bit entropy without mnemonic (
--no-mnemonic) - Deterministic: Generate from custom seed (
--seed)
See falcon create documentation for details.
License
This project is licensed under the AGPL.
Directories
¶
| Path | Synopsis |
|---|---|
|
Package algorand defines Algorand accounts controlled by FALCON keys.
|
Package algorand defines Algorand accounts controlled by FALCON keys. |
|
cmd
|
|
|
falcon
command
|
|
|
Package mnemonic provides functions to generate and validate mnemonic phrases based on the BIP-39 standard, and to derive Falcon seeds from them.
|
Package mnemonic provides functions to generate and validate mnemonic phrases based on the BIP-39 standard, and to derive Falcon seeds from them. |