Initial commit

Initial commit of shell scripts and rough draft for the readme file.

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2015 Kevin
+Copyright (c) 2015 Kevin Douglas
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,2 +1,28 @@
-# asc-key-to-qr-code
+# Paper Backups of Ascii PGP Keys
+
 Shell scripts to convert between ascii armor PGP keys and QR codes for paper backup
+
+# Convert Ascii Armor Key Files To QR Code Images
+
+    [kevin@computer]$ asc2qr.sh ~/gpg_public_key.asc 
+    generating QR1.png
+    generating QR2.png
+
+    [kevin@computer]$ ls -l
+    total 24
+    -rw-r--r--  1 kevin  group  6873 Mar  7 11:30 QR1.png
+    -rw-r--r--  1 kevin  group  1251 Mar  7 11:30 QR2.png
+
+# Convert QR Code Images to Ascii Armor Key Files
+
+    [kevin@computer]$ qr2asc.sh *.png
+    decoding QR1.png
+    decoding QR2.png
+
+    [kevin@computer]$ ls -l
+    total 32
+    -rw-r--r--  1 kevin  group  3127 Mar  7 11:30 mykey.asc
+
+    [kevin@computer]$ diff ~/gpg_public_key.asc mykey.asc 
+    [kevin@computer]$
+

asc2qr.sh

@@ -0,0 +1,82 @@
+#!/bin/bash
+
+#####
+#
+# Author: Kevin Douglas <douglk@gmail.com>
+#
+# Simple command line script to backup ascii armor gpg keys to paper. You can
+# use the following commands to export your keys in ascii armor format:
+#
+#   gpg --armor --export > pgp-public-keys.asc
+#   gpg --armor --export-secret-keys > pgp-private-keys.asc
+#   gpg --armor --gen-revoke [your key ID] > pgp-revocation.asc
+#
+# These can then be used to restore your keys if necessary.
+#
+# This script will allow you to convert the above ascii armor keys into a
+# printable QR code for long-term archival.
+#
+# This script depends on the following libraries/applications:
+#
+#   libqrencode (http://fukuchi.org/works/qrencode/)
+#
+# If you need to backup or restore binary keys, see this link to get started:
+#
+#   https://gist.github.com/joostrijneveld/59ab61faa21910c8434c#file-gpg2qrcodes-sh
+#
+#####
+
+# Maximum chuck size to send to the QR encoder. QR version 40 supports
+# 2,953 bytes of storage.
+file_split_size=2800
+
+# Prefix string for the PNG images that are produced
+image_prefix="QR"
+
+# Argument/usage check
+if [ $# -ne 1 ]; then
+	echo "usage: `basename ${0}` <ascii armor key file>"
+	exit 1
+fi
+
+asc_key=${1}
+if [ ! -f ${asc_key} ]; then
+	echo "key file not found: ${asc_key}"
+	exit 1
+fi
+
+# Create a temp file to use as a pattern for splitting the input key file.
+# This helps protect against file collisions in the current directory.
+export TMPDIR=""
+tmp_file=$(mktemp keyparts.XXXXXX)
+if [ $? -ne 0 ]; then
+	echo "failed to create temporary file"
+	exit 1
+fi
+
+# Split the key file into usable chunks that the QR encoder can consume
+split -b ${file_split_size} ${asc_key} "${tmp_file}."
+
+# For each chunk, encode it into a qc image
+index=1
+for file in ${tmp_file}.*; do
+	img="${image_prefix}${index}.png"
+	echo "generating ${img}"
+	cat ${file} | qrencode -o ${img}
+	if [ $? -ne 0 ]; then
+		echo "failed to encode image"
+		exit 2
+	fi
+	index=$((index+1))
+done
+
+# Find the correct secure deletion utility (srm on Mac, shred on Linux)
+sec_del="srm"
+which ${sec_del} 2>&1 1>/dev/null
+if [ $? -ne 0 ]; then
+	sec_del="shred --remove"
+fi
+
+# Securely clean up temporary files
+${sec_del} ${tmp_file}
+${sec_del} ${tmp_file}.*

qr2asc.sh

@@ -0,0 +1,74 @@
+#!/bin/bash
+
+#####
+#
+# Author: Kevin Douglas <douglk@gmail.com>
+#
+# Simple command line script to restore ascii armor gpg keys from a QR image.
+# You can use the following commands to import your restored keys:
+#
+#   gpg --import pgp-public-keys.asc
+#   gpg --import pgp-private-keys.asc
+#
+# This script will allow you to convert QR images created with asc2qr.sh
+# info an ascii armor pgp key.
+#
+# This script depends on the following libraries/applications:
+#
+#   libqrencode (http://fukuchi.org/works/qrencode/)
+#   zbar (http://zbar.sourceforge.net)
+#
+# If you need to backup or restore binary keys, see this link to get started:
+#
+#   https://gist.github.com/joostrijneveld/59ab61faa21910c8434c#file-gpg2qrcodes-sh
+#
+#####
+
+# Name of the output key after decoding
+output_key_name="mykey.asc"
+
+# Argument/usage check
+if [ $# -lt 1 ]; then
+	echo "usage: `basename ${0}` <QR image 1> [QR image 2] [...]"
+	exit 1
+fi
+
+# Create a temp file to use as a pattern for splitting the input key file.
+# This helps protect against file collisions in the current directory.
+export TMPDIR=""
+tmp_file=$(mktemp keyparts.XXXXXX)
+if [ $? -ne 0 ]; then
+	echo "failed to create temporary file"
+	exit 1
+fi
+
+# For each image on the command line, decode it into text
+index=1
+for img in "$@"; do
+	if [ ! -f ${img} ]; then
+		echo "image file not found: ${img}"
+		exit 1
+	fi
+	asc_key="${tmp_file}.${index}"
+	echo "decoding ${img}"
+	zbarimg --raw ${img} 2>/dev/null | perl -p -e 'chomp if eof' > ${asc_key}
+	if [ $? -ne 0 ]; then
+		echo "failed to decode QR image"
+		exit 2
+	fi
+	index=$((index+1))
+done
+
+echo "creating ${output_key_name}"
+cat ${tmp_file}.* > ${output_key_name}
+
+# Find the correct secure deletion utility (srm on Mac, shred on Linux)
+sec_del="srm"
+which ${sec_del} 2>&1 1>/dev/null
+if [ $? -ne 0 ]; then
+	sec_del="shred --remove"
+fi
+
+# Securely clean up temporary files
+${sec_del} ${tmp_file}
+${sec_del} ${tmp_file}.*