Add frontend, backend and CLI

frontend/components/utilities/crypto.js

@@ -0,0 +1,105 @@
+const nacl = require("tweetnacl");
+nacl.util = require("tweetnacl-util");
+const aes = require("../aes-256-gcm");
+
+/**
+ * Return assymmetrically encrypted [plaintext] using [publicKey] where
+ * [publicKey] likely belongs to the recipient.
+ * @param {Object} obj
+ * @param {String} obj.plaintext - plaintext to encrypt
+ * @param {String} obj.publicKey - public key of the recipient
+ * @param {String} obj.privateKey - private key of the sender (current user)
+ * @returns {Object} obj
+ * @returns {String} ciphertext - base64-encoded ciphertext
+ * @returns {String} nonce - base64-encoded nonce
+ */
+const encryptAssymmetric = ({ plaintext, publicKey, privateKey }) => {
+	const nonce = nacl.randomBytes(24);
+	const ciphertext = nacl.box(
+		nacl.util.decodeUTF8(plaintext),
+		nonce,
+		nacl.util.decodeBase64(publicKey),
+		nacl.util.decodeBase64(privateKey)
+	);
+
+	return {
+		ciphertext: nacl.util.encodeBase64(ciphertext),
+		nonce: nacl.util.encodeBase64(nonce),
+	};
+};
+
+/**
+ * Return assymmetrically decrypted [ciphertext] using [privateKey] where
+ * [privateKey] likely belongs to the recipient.
+ * @param {Object} obj
+ * @param {String} obj.ciphertext - ciphertext to decrypt
+ * @param {String} obj.nonce - nonce
+ * @param {String} obj.publicKey - base64-encoded public key of the sender
+ * @param {String} obj.privateKey - base64-encoded private key of the receiver (current user)
+ * @param {String} plaintext - UTF8 plaintext
+ */
+const decryptAssymmetric = ({ ciphertext, nonce, publicKey, privateKey }) => {
+	const plaintext = nacl.box.open(
+		nacl.util.decodeBase64(ciphertext),
+		nacl.util.decodeBase64(nonce),
+		nacl.util.decodeBase64(publicKey),
+		nacl.util.decodeBase64(privateKey)
+	);
+
+	return nacl.util.encodeUTF8(plaintext);
+};
+
+/**
+ * Return symmetrically encrypted [plaintext] using [key].
+ * @param {Object} obj
+ * @param {String} obj.plaintext - plaintext to encrypt
+ * @param {String} obj.key - 16-byte hex key
+ */
+const encryptSymmetric = ({ plaintext, key }) => {
+	let ciphertext, iv, tag;
+	try {
+		const obj = aes.encrypt(plaintext, key);
+		ciphertext = obj.ciphertext;
+		iv = obj.iv;
+		tag = obj.tag;
+	} catch (err) {
+		console.log("Failed to perform encryption");
+		console.log(err);
+		process.exit(1);
+	}
+
+	return {
+		ciphertext,
+		iv,
+		tag,
+	};
+};
+
+/**
+ * Return symmetrically decypted [ciphertext] using [iv], [tag],
+ * and [key].
+ * @param {Object} obj
+ * @param {String} obj.ciphertext - ciphertext to decrypt
+ * @param {String} obj.iv - iv
+ * @param {String} obj.tag - tag
+ * @param {String} obj.key - 32-byte hex key
+ *
+ */
+const decryptSymmetric = ({ ciphertext, iv, tag, key }) => {
+	let plaintext;
+	try {
+		plaintext = aes.decrypt(ciphertext, iv, tag, key);
+	} catch (err) {
+		console.log("Failed to perform decryption");
+		process.exit(1);
+	}
+
+	return plaintext;
+};
+
+module.exports = {
+	encryptAssymmetric,
+	decryptAssymmetric,
+	encryptSymmetric,
+	decryptSymmetric,
+};