keygen

Deterministic password generator using a chained hash pipeline.

Description

keygen is a minimal shell script that generates deterministic passwords and hashes from stdin input using a chained pipeline of standard Unix hash utilities:

md5sum → sha1sum → sha224sum → sha256sum → sha384sum → sha512sum → base64

Designed for use in automated encryption workflows where reproducible key derivation from a known secret is required — no external dependencies beyond standard coreutils.

Usage

printf 'secret' | keygen [OPTIONS]
echo 'secret'   | keygen [OPTIONS]
keygen [OPTIONS]          # prompts for input interactively

Options

Option	Description
hash	Output raw hash instead of base64-encoded password
-s	Inject special characters (!@#%) every 5 characters
N	Truncate output to N characters (default: 500)

Examples

# Generate a password from a secret (piped)
printf 'mysecret' | keygen

# Interactive input (prompts for text)
keygen

# Generate a shorter password (32 chars)
printf 'mysecret' | keygen 32

# Generate a password with special characters
printf 'mysecret' | keygen -s 32

# Output raw hash only
printf 'mysecret' | keygen hash

# Use as key derivation in a script
key=$(printf '%s\n' "$disk_id" | keygen 64)

Dependencies

• md5sum, sha1sum, sha224sum, sha256sum, sha384sum, sha512sum — coreutils
• base64 — coreutils
• awk, cut — standard Unix tools

Security Notes

• Output is fully deterministic: same input always produces same output
• No state, no files, no network — runs entirely in memory
• Intended for use in pipelines where the input secret is already protected
• Do not use with weak or short secrets