Encrypted zip files on OSX

Jonathan Hartley

2012-10-09 10:17

Update: I've since switched to KeePassXC, the community fork of KeePassX, an open source, cross-platorm, local-first, encrypted password storage program.

My passwords and other miscellany are in a plain text file within an encrypted zip. Since starting to use OSX I've been looking for a way to access my passwords such that:

I get prompted for the decryption password.
The file gets unzipped, but not in the same directory, because that's synced to Dropbox, so would send my plaintext passwords to them every time I accessed them. Maybe to /tmp?
The plaintext file within the zip is opened in \$EDITOR.
Wait for me to close \$EDITOR, then remove my plaintext passwords from the filesystem.
Before deleting the passwords, check if I've updated them. If so, put the new updated version back into the original zip file.
Don't forget to keep the updated zip file encrypted, using the same password as before, without prompting for it again.

I failed to find an existing app which would do all this (although I had no trouble on Linux or even on Windows.) Hence, resorting to good old Bash:

#!/bin/bash

ZIPDIR="$HOME/docs/org"

read -s -p "Password:" key

cd $ZIPDIR
unzip -P $key passwords.zip passwords.txt -d $TMPDIR
if [[ $? != 0 ]] ; then
    exit 1
fi

cd "$TMPDIR"
touch passwords.datestamp
$EDITOR passwords.txt
if [[ passwords.txt -nt passwords.datestamp ]] ; then
    zip -P $key -r "$ZIPDIR/passwords.zip" passwords.txt
fi

rm passwords.txt
rm passwords.datestamp

I don't expect this to be watertight, but seems good enough for today. I'm happy to hear suggestions.