Kali Linux Tutorials

Cryptr is a simple shell utility for encrypting and decryption files using OpenSSL.

Installation

git clone https://github.com/nodesocket/cryptr.git
ln -s “$PWD”/cryptr/cryptr.bash /usr/local/bin/cryptr

Bash tab completion

Add tools/cryptr-bash-completion.bash to your tab completion file directory.

API/Commands

Encrypt

encrypt <file> – Encryptes file with OpenSSL AES-256 cipher block chaining. Writes an encrypted file out (ciphertext)appending .aes extension.

➜ cryptr encrypt ./secret-file
enter aes-256-cbc encryption password:
Verifying – enter aes-256-cbc encryption password:

➜ ls -alh
-rw-r–r– 1 user group 1.0G Oct 1 13:33 secret-file
-rw-r–r– 1 user group 1.0G Oct 1 13:34 secret-file.aes

You may optionally define the password to use when encrypting using the CRYPTR_PASSWORD environment variable. This enables non-interactive/batch operations.

➜ CRYPTR_PASSWORD=A1EO7S9SsQYcPChOr47n cryptr encrypt ./secret-file

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Decrypt

decrypt <file.aes> – Decrypt encrypted file using OpenSSL AES-256 cipher block chaining. Writes a decrypted file out (plaintext) removing .aes extension.

➜ ls -alh
-rw-r–r– 1 user group 1.0G Oct 1 13:34 secret-file.aes

➜ cryptr decrypt ./secret-file.aes
enter aes-256-cbc decryption password:

➜ ls -alh
-rw-r–r– 1 user group 1.0G Oct 1 13:35 secret-file
-rw-r–r– 1 user group 1.0G Oct 1 13:34 secret-file.aes

You may optionally define the password to use when decrypting using the CRYPTR_PASSWORD environment variable. This enables non-interactive/batch operations.

➜ CRYPTR_PASSWORD=A1EO7S9SsQYcPChOr47n cryptr decrypt ./secret-file.aes

Help

help – Displays help

➜ cryptr help
Usage: cryptr command
encrypt <file> Encrypt file
decrypt <file.aes> Decrypt encrypted file
help Displays help
version Displays the current version

Version

version – Displays the current version

➜ cryptr version
cryptr 2.1.1

Default

default – Displays the current version and help

➜ cryptr cryptr 2.1.1
Usage: cryptr command

encrypt <file> Encrypt file
decrypt<file.aes> Decrypt encrypted file
help Displays help
version Displays the current version

Versioning

For transparency and insight into the release cycle, and for striving to maintain backward compatibility, cryptr will be maintained under the semantic versioning guidelines.

Releases will be numbered with the follow format:

<major>.<minor>.<patch>

And constructed with the following guidelines:

• Breaking backward compatibility bumps the major (and resets the minor and patch)
• New additions without breaking backward compatibility bumps the minor (and resets the patch)
• Bug fixes and misc changes bumps the patch

For more information on semantic versioning, visit http://semver.org/.

License & Legal

Copyright 2019 Justin Keller

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.