Small data: encrypting server side

For example, to encrypt a message with the key my_sym_key server side, the following command can be used:

> cosmian kms sym encrypt --key-id my_sym_key /tmp/secret.txt

The encrypted file is available at "/tmp/secret.enc"

To decrypt a message with the key my_sym_key, the following command can be used:

> cosmian kms sym decrypt --key-id my_sym_key --output-file /tmp/secret.recovered.txt /tmp/secret.enc

The decrypted file is available at /tmp/secret.recovered.txt