add script

bin/ghcrypt

@@ -0,0 +1,138 @@
+#! /bin/sh
+
+CONFIG_FILE=$HOME/.ghcrypt
+
+usage() {
+ echo 'ghcrypt v0.1'
+ echo 'Encrypt or decrypt file using GitHub username.'
+ echo
+ echo 'Usage:'
+ echo ' Encrypt and Sign: ghcrypt [--key privatekey] file github-username(reciever)'
+ echo ' Verify and Decrypt: ghcrypt [--key privatekey] file.enc.tar github-username(sender)'
+ echo
+}
+
+if [ x"$1" = x ]; then
+ usage
+ exit 1
+fi
+
+if [ x"$1" = "x--help" -o x"$1" = "x-h" ]; then
+ usage
+ exit
+fi
+
+if [ x"$1" = "x--key" ]; then
+ shift
+ PRIVATE_KEY=$1
+ shift
+fi
+
+FILE=$1
+GITHUB_USER=$2
+
+if [ x"$PRIVATE_KEY" = x ]; then
+ if [ ! -f $CONFIG_FILE ]; then
+ echo 'ERROR: No config file:' $CONFIG_FILE
+ echo
+ echo ' Write your GitHub private key path:'
+ echo ' $ echo /home/yourname/.ssh/id_rsa > ~/.ghcrypt'
+ echo ' $ chmod 400 ~/.ghcrypt'
+ echo
+ exit 1
+ fi
+ PRIVATE_KEY=$(cat $CONFIG_FILE)
+fi
+
+if [ ! -f $FILE ]; then
+ echo "ERROR: Target file must be file: $FILE"
+ exit 1
+fi
+if [ x"$GITHUB_USER" = x ]; then
+ echo "ERROR: GitHub user name required."
+ usage
+ exit 1
+fi
+if [ ! -f $PRIVATE_KEY ]; then
+ echo "ERROR: Private key doesn't exist: $PRIVATE_KEY"
+ exit 1
+fi
+
+download_publickey() {
+ wget -O $PUBLIC_KEY https://github.com/$GITHUB_USER.keys || exit $?
+
+ FINGERPRINT=`ssh-keygen -l -f $PUBLIC_KEY` || exit $?
+ echo "----------------------------------------------------------------"
+ echo "$1: $GITHUB_USER"
+ echo " https://github.com/$GITHUB_USER"
+ echo " $FINGERPRINT"
+ echo "----------------------------------------------------------------"
+ ssh-keygen -f $PUBLIC_KEY -e -m PKCS8 > $PUBLIC_KEY.pem || exit $?
+}
+
+
+case "$FILE" in
+*\.enc\.tar)
+ BASENAME=$(basename -s .tar $FILE)
+ TMP_DIR=$BASENAME
+ INFILE=$TMP_DIR/$BASENAME
+ SIGFILE=$TMP_DIR/$BASENAME.sig
+ OUTFILE=$(basename -s .enc.tar $FILE)
+
+ if [ -e $TMP_DIR ]; then
+ echo "ERROR: $TMP_DIR already exits."
+ exit 1
+ fi
+ if [ -e $OUTFILE ]; then
+ echo "ERROR: $OUTFILE already exits."
+ exit 1
+ fi
+
+ PUBLIC_KEY=$TMP_DIR/$GITHUB_USER.keys
+
+ tar xf $FILE || exit $?
+ download_publickey Sender
+
+ openssl sha1 -verify $PUBLIC_KEY.pem -signature $SIGFILE $INFILE || exit $?
+ openssl rsautl -in $INFILE -inkey $PRIVATE_KEY -decrypt -out $OUTFILE || exit $?
+
+ rm $INFILE $INFILE.sig
+ rm $PUBLIC_KEY $PUBLIC_KEY.pem
+ rmdir $TMP_DIR
+
+ echo
+ echo "Successfully Verified and Decrypted!"
+ echo " $FILE --> $OUTFILE"
+ echo
+ ;;
+*)
+ TMP_DIR=$FILE.enc
+
+ if [ -e $TMP_DIR ]; then
+ echo "ERROR: $TMP_DIR already exits."
+ exit 1
+ fi
+ if [ -e $TMP_DIR.tar ]; then
+ echo "ERROR: $TMP_DIR.tar already exits."
+ exit 1
+ fi
+ mkdir $TMP_DIR || exit $?
+
+ PUBLIC_KEY=$TMP_DIR/$GITHUB_USER.keys
+
+ download_publickey Reciever
+
+ openssl rsautl -in $FILE -inkey $PUBLIC_KEY.pem -pubin -encrypt -out $TMP_DIR/$FILE.enc || exit $?
+ openssl sha1 -sign $PRIVATE_KEY $TMP_DIR/$FILE.enc > $TMP_DIR/$FILE.enc.sig || exit $?
+
+ rm $PUBLIC_KEY $PUBLIC_KEY.pem
+ tar cf $FILE.enc.tar $TMP_DIR
+ rm $TMP_DIR/$FILE.enc $TMP_DIR/$FILE.enc.sig
+ rmdir $TMP_DIR
+
+ echo
+ echo "Successfully Encrypted and Signed!"
+ echo " $FILE --> $FILE.enc.tar"
+ echo
+ ;;
+esac