splitkey

A command-line tool for splitting and combining secrets using Shamir's Secret Sharing.

Installation

shards install
crystal build src/splitkey.cr --release

Usage

Split a secret

Split a secret into multiple shares, where a threshold number of shares is required to reconstruct it:

# Split into 5 shares, requiring 3 to reconstruct
# Generates share-1.txt, share-2.txt, share-3.txt, share-4.txt, share-5.txt
splitkey split -s "my password" -n 5 -k 3

# Generate QR codes (as png)
splitkey split -s "my password" -n 5 -k 3 --format qr

Options:

• -s, --secret SECRET - Secret to split (required)
• -n, --shares N - Total number of shares to create (required)
• -k, --threshold K - Minimum shares needed to reconstruct (required)
• -o, --output PREFIX - Output file prefix (default: share)
• -f, --format FORMAT - Output format: text, qr (default: text)

Combine shares

Combine shares to recover the original secret:

# Combine text shares
splitkey combine share-1.txt share-2.txt share-3.txt

The recovered secret is printed to stdout.

License

MIT