Encrypt and decrypt files

• https://man.cx/openssl(1)

Using OpenSSL

Encrypt and decrypt a file (GPG can also be used for encrypting and decrypting files)
Using aes-256-cbc cypher, You will be prompted for a password when encrypting that has to be used for decrypting.

• Encrypt file (openssl enc):

openssl enc -aes-256-cbc -in un_encrypted.data -out encrypted.data

You can use file command to verify file type.

file encrypted.data
encrypted.data: openssl enc'd data with salted password

Encrypt file providing password on the command line, be aware that your password will be store on history of your shell):

openssl aes-256-cbc -a -salt -in twitterpost.txt -out foo.enc -pass file:<( echo -n "someGoodPassword" )

• Decrypt file (openssl enc -d):

openssl enc -d -aes-256-cbc -in encrypted.data -out un_encrypted.data

macOS options:

• -salt Use a salt in the key derivation routines (the default). When the salt is being used the first eight bytes of the encrypted data are reserved for the salt: it is randomly generated when encrypting a file and read from the encrypted file when it is decrypted.

Related terms

• zip -r -0 -e encrypted_file.zip /path/to/files
• PGP

See also

• OpenSSL: RSA, ECDSA, WolfSSL, AES, Diffie-Hellman (DH) key-exchange, /etc/ssl/openssl.cnf, OpenSSL v3
• Encryption, openssl, ecryptfs, encfs, GPG, PGP, Symantec Encryption Desktop, VeraCrypt, CMEK, BitLocker, OAEP, Cypher

https://unix.stackexchange.com/questions/162960/how-can-i-encrypt-a-file

https://stackoverflow.com/a/31552829