The purpose of DevCrypt is to improve otherwise insecure sharing of development environment (that is, "low value") secrets, such as test database passwords. If you currently keep these secrets unencrypted in your source code or shared via e.g. email, DevCrypt may be for you.

DO NOT USE DEVCRYPT TO PROTECT PRODUCTION OR OTHERWISE HIGH-VALUE SECRETS!

While DevCrypt is built on secure cryptographic elements, it is immature and hasn't been thoroughly reviewed by anyone, let alone cryptographic experts.

For production secrets, consider Mozilla's SOPS.

DevCrypt is written in Go. Currently there are no binaries available, so you have to compile from source.

To install the devcrypt binary to $GOBIN (by default, ~/go/bin/devcrypt):

$ go get -u github.com/lann/devcrypt
$ devcrypt help

or, to just compile the binary:

$ git clone https://github.com/lann/devcrypt
$ cd devcrypt
$ go build
$ ./devcrypt help

$ devcrypt keygen
Generating key with label "lann@computer"...
Wrote private key to "/home/lann/.config/devcrypt/devcrypt_key"
Wrote public key to "/home/lann/.config/devcrypt/devcrypt_key.pub"
Public key:
devcrypt-key cpCWOPP0/afWR3YkfrxZ6KptOO9pAZflm3LF6ChoTXU= lann@computer

$ echo "SECRET_KEY=topSecret" > .env
$ devcrypt encrypt .env
Encrypted to ".env.devcrypt"

$ devcrypt keygen -k bobs_key -l bob@boblandia
...
Wrote public key to "bobs_key.pub"
...
$ devcrypt add .env.devcrypt bobs_key.pub
Adding public key labeled "bob@boblandia"
Updated ".env.devcrypt"

$ devcrypt decrypt .env.devcrypt
Decrypted to ".env"

$ devcrypt remove .env.devcrypt lann@computer
Removing public key by label "lann@computer":
devcrypt-key cpCWOPP0/afWR3YkfrxZ6KptOO9pAZflm3LF6ChoTXU= lann@computer

Updated ".env.devcrypt"

$ devcrypt decrypt .env.devcrypt
Error: unsealing file: no key box found for key labeled "lann@computer"

DevCrypt uses cryptographic elements from NaCl as implemented in golang.org/x/crypto/nacl.

Files are encryped with secretbox using a random "file key". That key is then encrypted into one or more "sealed boxes", which allow encryption with a public key and decryption with the matching private key. The sealed boxes and matching public keys are stored along with the encrypted file in a single text file.

Users with private keys that match one of the "sealed boxes" can decrypt the file by looking up the sealed box based on their public key, decrypting the file key using their private key, then decrypting the file contents with the file key. They can also add new public keys to the encrypted file by decrypting the file key and then reencrypting it into a new sealed box.