agenix/pkgs/agenix.nix
2020-12-18 19:23:47 -08:00

157 lines
3.8 KiB
Nix

{writeShellScriptBin, runtimeShell, pkgs} :
let
rage = pkgs.callPackage ./rage.nix {};
ageBin = "${rage}/bin/rage";
in
writeShellScriptBin "agenix" ''
set -Eeuo pipefail
PACKAGE="agenix"
function show_help () {
echo "$PACKAGE - edit and rekey age secret files"
echo " "
echo "$PACKAGE -e FILE [-i PRIVATE_KEY]"
echo "$PACKAGE -r [-i PRIVATE_KEY]"
echo ' '
echo 'options:'
echo '-h, --help show help'
echo '-e, --edit FILE edits FILE using $EDITOR'
echo '-r, --rekey re-encrypts all secrets with specified recipients'
echo '-i, --identity identity to use when decrypting'
echo ' '
echo 'FILE an age-encrypted file'
echo ' '
echo 'PRIVATE_KEY a path to a private SSH key used to decrypt file'
echo ' '
echo 'EDITOR environment variable of editor to use when editing FILE'
echo ' '
echo 'RULES environment variable with path to Nix file specifying recipient public keys.'
echo "Defaults to './secrets.nix'"
echo ' '
echo "age binary path: ${ageBin}"
echo "age version: $(${ageBin} --version)"
}
test $# -eq 0 && (show_help && exit 1)
REKEY=0
DEFAULT_DECRYPT=(--decrypt)
while test $# -gt 0; do
case "$1" in
-h|--help)
show_help
exit 0
;;
-e|--edit)
shift
if test $# -gt 0; then
export FILE=$1
else
echo "no FILE specified"
exit 1
fi
shift
;;
-i|--identity)
shift
if test $# -gt 0; then
DEFAULT_DECRYPT+=(--identity "$1")
else
echo "no PRIVATE_KEY specified"
exit 1
fi
shift
;;
-r|--rekey)
shift
REKEY=1
;;
*)
show_help
exit 1
;;
esac
done
RULES=''${RULES:-./secrets.nix}
function cleanup {
if [ ! -z ''${CLEARTEXT_DIR+x} ]
then
rm -rf "$CLEARTEXT_DIR"
fi
if [ ! -z ''${REENCRYPTED_DIR+x} ]
then
rm -rf "$REENCRYPTED_DIR"
fi
}
trap "cleanup" 0 2 3 15
function edit {
FILE=$1
KEYS=$((nix-instantiate --eval -E "(let rules = import $RULES; in builtins.concatStringsSep \"\n\" rules.\"$FILE\".publicKeys)" | sed 's/"//g' | sed 's/\\n/\n/g') || exit 1)
if [ -z "$KEYS" ]
then
>&2 echo "There is no rule for $FILE in $RULES."
exit 1
fi
CLEARTEXT_DIR=$(mktemp -d)
CLEARTEXT_FILE="$CLEARTEXT_DIR/$(basename "$FILE")"
if [ -f "$FILE" ]
then
DECRYPT=("''${DEFAULT_DECRYPT[@]}")
if [ -f "$HOME/.ssh/id_rsa" ]; then
DECRYPT+=(--identity "$HOME/.ssh/id_rsa")
fi
if [ -f "$HOME/.ssh/id_ed25519" ]; then
DECRYPT+=(--identity "$HOME/.ssh/id_ed25519")
fi
DECRYPT+=(-o "$CLEARTEXT_FILE" "$FILE")
${ageBin} "''${DECRYPT[@]}" || exit 1
cp "$CLEARTEXT_FILE" "$CLEARTEXT_FILE.before"
fi
$EDITOR "$CLEARTEXT_FILE"
if [ ! -f "$CLEARTEXT_FILE" ]
then
echo "$FILE wasn't created."
return
fi
[ -f "$FILE" ] && [ "$EDITOR" != ":" ] && diff "$CLEARTEXT_FILE.before" "$CLEARTEXT_FILE" 1>/dev/null && echo "$FILE wasn't changed, skipping re-encryption." && return
ENCRYPT=()
while IFS= read -r key
do
ENCRYPT+=(--recipient "$key")
done <<< "$KEYS"
REENCRYPTED_DIR=$(mktemp -d)
REENCRYPTED_FILE="$REENCRYPTED_DIR/$(basename "$FILE")"
ENCRYPT+=(-o "$REENCRYPTED_FILE")
${ageBin} "''${ENCRYPT[@]}" <"$CLEARTEXT_FILE" || exit 1
mv -f "$REENCRYPTED_FILE" "$1"
}
function rekey {
FILES=$((nix-instantiate --eval -E "(let rules = import $RULES; in builtins.concatStringsSep \"\n\" (builtins.attrNames rules))" | sed 's/"//g' | sed 's/\\n/\n/g') || exit 1)
for FILE in $FILES
do
echo "rekeying $FILE..."
EDITOR=: edit "$FILE"
cleanup
done
}
[ $REKEY -eq 1 ] && rekey && exit 0
edit "$FILE" && cleanup && exit 0
''