Keeps files along with their GPG-encrypted copy.

.gitignore

# Ignore everything except .gpg files
# Useful when you want to sync encrypted files only.
*
!*.gpg
!*/

sync_encryption.sh

#!/bin/sh
## Copyright (c) 2015 Rodolphe Breard
## 
## Permission to use, copy, modify, and/or distribute this software for any
## purpose with or without fee is hereby granted, provided that the above
## copyright notice and this permission notice appear in all copies.
## 
## THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
## WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
## MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
## ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
## WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
## ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
## OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
##

set -e

GPG_ID_FILE=".gpg-id"
test -f "$GPG_ID_FILE" || (echo "$GPG_ID_FILE: No such file" && exit 2)
KEY_ID=$(cat "$GPG_ID_FILE")
DIR="."
test "$1" != "" && DIR="$1"

gpg_encrypt_file () {
    FILENAME="$1"
    GPG_FILENAME="$FILENAME.gpg"

    if [ ! -f "$GPG_FILENAME" ]; then
        echo "Encrypting $FILENAME...";
        gpg --quiet -r "$KEY_ID" --output "$GPG_FILENAME" --encrypt --no-encrypt-to "$FILENAME"
    fi
}

gpg_decrypt_file () {
    GPG_FILENAME="$1"
    FILENAME="$(dirname "$GPG_FILENAME")/$(basename "$GPG_FILENAME" ".gpg")"

    if [ ! -f "$FILENAME" ]; then
        echo "Decrypting $FILENAME...";
        gpg --quiet -r "$KEY_ID" --output "$FILENAME" --decrypt "$GPG_FILENAME"
    fi
}

gpg_encrypt_dir () {
    find "$1" -not -path '*/\.*' -not -name '*~' -not -name "$(basename $0)" -not -name "*.gpg" -type f -print | while read file; do
        gpg_encrypt_file "$file";
    done
}

gpg_decrypt_dir () {
    find "$1" -not -path '*/\.*' -not -name '*~' -not -name "$(basename $0)" -name "*.gpg" -type f -print | while read file; do
        gpg_decrypt_file "$file";
    done
}

sync_dir () {
    gpg_encrypt_dir "$1"
    gpg_decrypt_dir "$1"
}

sync_dir "$DIR"