Add create_ssl script

overlays/create_ssl.nix

@@ -0,0 +1,28 @@
+{ writeShellScriptBin, openssl, ...}:
+
+writeShellScriptBin "create_ssl" ''
+set -e -o pipefail
+name="''${1}"
+root_key="''${2}"
+
+function usage {
+	echo "USAGE: create_ssl <cert name> <root path>"
+}
+
+if [ -z "''${name}" ]; then
+	usage
+	exit 1
+fi
+
+if [ -z "''${root_key}" ]; then
+	usage
+	exit 1
+fi
+
+# Create the certificate key
+${openssl}/bin/openssl ecparam -out "''${name}.key" -name prime256v1 -genkey
+# Create the CSR
+${openssl}/bin/openssl req -name -sha256 -key "''${name}.key" -out "''${name}.csr"
+# Sign it
+${openssl}/bin/openssl x509 -req -in "''${name}.csr" -CA "''${root_key}.crt" -CAkey "''${root_key}.key" -CAcreateserial -out "''${name}.crt" -days 3650 -sha256
+''