Andy Dixon
be09659f8f
genkey optionally takes a second passphrase that unlocks a separate decoy identity. Every command run with it sees and changes only decoy files; records sealed to the other key are skipped silently. The key file always carries two equal-size slots in random order, with random bytes in an unused slot, and both slots are always tried. init seeds each vault with 8-32 entries sealed to a discarded key, so real files are indistinguishable from filler to a decoy-only holder.
vault
A post-quantum encrypted file vault in a single binary.
Files are encrypted with a hybrid FrodoKEM-640 + ML-KEM-768 key encapsulation and ChaCha20-Poly1305. The vault directory holds only randomly named ciphertexts. Names, sizes, modes and timestamps live inside encrypted catalogue records of one fixed size. File bodies are padded to power-of-two buckets.
Build
go build . # produces ./vault
go test ./...
Use
vault genkey # create ~/.vault/key, protected by a passphrase
vault init # create ~/.vault/store
vault add report.pdf # stored as report.pdf
vault add report.pdf work/2026 # stored as work/2026/report.pdf
vault add ./photos # every regular file under photos/
vault list # everything
vault list work # everything under work/
vault get work/2026/report.pdf # writes ./report.pdf
vault get report.pdf -o copy.pdf
vault mv report.pdf old/report.pdf
vault rm old/report.pdf
Adding a name that already exists replaces it. get refuses to overwrite an
existing file and writes nothing until the whole object has authenticated.
--key PATH and --vault DIR work with every command. They default to
$VAULT_KEY and $VAULT_DIR, then to ~/.vault/key and ~/.vault/store.
The passphrase is read from the terminal, or from $VAULT_PASSPHRASE for
scripts.
Decoy passphrase
vault genkey offers an optional second passphrase. In scripts, set
$VAULT_DECOY_PASSPHRASE. Each passphrase unlocks its own key, so a command
run with the decoy passphrase lists, adds and retrieves only decoy files. The
real files never appear.
vault genkey # set a passphrase, then a decoy passphrase
vault add plans.pdf # with the real passphrase
vault add shopping.txt # with the decoy passphrase
vault list # shows only what that passphrase stored
Two measures keep the real files deniable:
- The key file always holds two slots of identical size in random order. An unused slot is random bytes, so the file does not show whether a decoy exists or which slot is real.
initfills every vault with 8 to 32 random entries that nobody can decrypt. Anyone holding only the decoy passphrase sees unreadable entries in every vault, so hidden real files look the same as filler.
A decoy can only be set when the key is created. Someone who watches the vault over time can still see it grow when real files are added.
Limits
- One writer at a time. Concurrent writes to the same vault are not locked.
- The storage host can see how many files exist, their size buckets and when the vault changes.
- The key file is the only way in. Losing it or its passphrase loses the data.
Licence
GPL-3.0-or-later. The cryptographic core is derived from Fury.