Storing password and confidential data across multiple computer is always a complex problem to solve. They are great tools, such as keypass, that can do this in a secure manner, but for some reason I always felt uneasy about giving my bank password to a 3rd party software.
So, I made my own. It's a simple file encrypted in aes-256-cbc using openssl.
Create a new encrypted file using this command:
echo "my new credential file" | openssl aes-256-cbc -e -a -salt -out mycredentials.encrypted
This creates the file "mycredentials.encrypted". You can then use the scripts below to read your credentials:
#!/usr/bin/env bash if [[ -x "$1" || ! -r "$1" ]]; then echo "usage: $0 <ciphered file>" exit 1 fi SECFILE=$1 CLEARTEXT=$(openssl aes-256-cbc -d -a -salt -in $SECFILE) if [ $? -gt 0 ]; then echo "Wrong password, cannot decrypt" exit $? else echo "$CLEARTEXT" fi
#!/usr/bin/env bash # store a password in a ciphered file if [[ $1 = "" || ! -r $1 ]]; then echo "usage: $0 <ciphered file>" exit 1 fi SECFILE=$1 # decipher access file CLEARTEXT=$(openssl aes-256-cbc -d -a -salt -in $SECFILE) if [ $? -gt 0 ]; then echo "Wrong password, cannot decrypt" exit $? fi # get new value to store echo "enter value to append (1 line)" echo -n "> " read PASSWD UPDATED_CLEARTEXT=$(echo -e "$CLEARTEXT\n$PASSWD") # cipher access file and delete temporary file echo "$UPDATED_CLEARTEXT"| openssl aes-256-cbc -e -a -salt -out $SECFILE.updated if [ $? -gt 0 ] then echo "Password encryption failed, password not stored in $SECFILE" else mv "$SECFILE.updated" "$SECFILE" echo "information successfully encrypted and store in $SECFILE" fi #clean up CLEARTEXT=$(dd if=/dev/urandom bs=128 count=128 2>/dev/null) PASSWD=$(dd if=/dev/urandom bs=128 count=128 2>/dev/null) UPDATED_CLEARTEXT=$(dd if=/dev/urandom bs=128 count=128 2>/dev/null)
There is a couple of drowbacks with this method:
- Your decrypted credentials are stored in cleartext in a BASH variable at some point, The variables are flushed at the end of the storage process, but you don't want to run this script on an untrusted machine
- Credentials are displayed in your terminal. Make sure you don't leave that open, and use ./getsecret.sh <credential_file> | grep "bank" to retrieve only the credentials you want, and not the whole file.
- The storage password requires that you type your password 3 times. That's the only safe way to encrypt/decrypt without passing the password on the command line.
It's definitely not a perfect solution, but I like to do things the hard way :)