Easily create encrypted backups of your Bitcoin wallet

backup-bitcoins.sh

#!/bin/bash

# backup-bitcoins.sh - Easily create encrypted backups of your Bitcoin wallet
# You need this tools / programs to run backup-bitcoins.sh:
# * 7z (usually in the package 7zip)
# * uuidgen (usually already installed)
#
#            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
#                    Version 2, December 2004
# 
# Copyright (C) 2004 Sam Hocevar
#  14 rue de Plaisance, 75014 Paris, France
# Everyone is permitted to copy and distribute verbatim or modified
# copies of this license document, and changing it is allowed as long
# as the name is changed.
# 
#            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
#   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
# 
#  0. You just DO WHAT THE FUCK YOU WANT TO.

CONFFILE=~/.backup-bitcoins

touch $CONFFILE

get_passwd() {
	while true; do
		echo -n "Password: " >&2
		read -s passwd1
		echo -ne "\nConfirm Password: " >&2
		read -s passwd2
		echo -ne "\n" >&2
		if [ "$passwd1" == "$passwd2" ]; then
			echo "$passwd1"
			passwd1=""
			passwd2=""
			break
		else
			sleep 2
			echo "Passwords do not match. Try again." >&2
		fi
	done
}

crypt_wallet() {
	WALLETFILE="$1"
	NEWFILE="$2"
	PASSWORD="$3"
	
	7z a -p"$PASSWORD" "$NEWFILE" "$WALLETFILE"
	PASSWORD=""
}

backup() {
	PASSWD=`get_passwd`
	TEMPFILE="/tmp/$(uuidgen -r).7z"
	
	crypt_wallet ~/.bitcoin/wallet.dat "$TEMPFILE" "$PASSWD"
	
	for destination in `cat "$CONFFILE"`; do
		while true; do
			if cp -f "$TEMPFILE" "$destination"; then 
				echo "Backed up to $destination"
				break
			else
				echo -ne "Could not copy to $destination. Retry?\ny/n: " >&2
				read yesno
				case "$yesno" in
					n|N|no) break; ;;
					*) continue; ;;
				esac
			fi
		done
	done
	
	rm -f "$TEMPFILE"
	PASSWD=""
}

list_destinations() {
	count=0
	for destination in `cat "$CONFFILE"`; do
		echo "#$count: $destination"
		count="$[$count+1]"
	done
}

delete_destination() {
	mv "$CONFFILE" "$CONFFILE.old"
	total=`wc -l < "$CONFFILE.old"`
	
	head -n $1 "$CONFFILE.old" > "$CONFFILE"
	tail -n "$[$total-($1+1)]" "$CONFFILE.old" >> "$CONFFILE"
}

add_destination() {
	for destination in `cat "$CONFFILE"`; do
		if [ "$destination" == "$1" ]; then return; fi
	done
	
	echo "$1" >> "$CONFFILE"
}

short_usage() {
	prgname=`basename "$1"`
	echo "Usage: $prgname command [additional parameters]" >&2
}

offer_help() {
	prgname=`basename "$1"`
	echo "Type \"$prgname help\" for more inforamtion." >&2
}

case $1 in
	add|add_destination)
		if [ "$2" == "" ]; then
			echo "$0: Command $1 needs one additional parameter." >&2
			offer_help
			exit 1
		else
			add_destination "$2"
		fi
		;;
	
	delete|remove|delete_destination|remove_destination)
		if [ "$2" == "" ]; then
			echo "$0: Command $1 needs one additional parameter." >&2
			offer_help
			exit 1
		else
			delete_destination "$2"
		fi
		;;
	
	list|list_destinations)
		list_destinations
		;;
	backup)
		backup
		;;
	
	help)
		short_usage
		cat <<-FOO
			Where command is one of these:
			
			add|add_destination new_destination
			adds the new_destination to the backup destinations
			
			list
			lists all backup destinations
			
			delete|remove|delete_destination|remove_destination index
			deletes the destination with the index from the backup destinations
			
			backup
			backup the bitcoin wallet
			
			help
			print this help
		FOO
		;;
	
	*)
		prgname=`basename "$0"`
		echo "$prgname: Unknown command: $1" >&2;
		short_usage "$0"
		offer_help "$0"
		;;
esac