decaffeinate: Convert AccessTokenEncryptor.coffee to JS

libraries/access-token-encryptor/lib/coffee/AccessTokenEncryptor.js

@@ -1,77 +1,100 @@
-crypto = require('crypto')
-
-ALGORITHM = 'aes-256-ctr'
-
-keyFn = (password, salt, callback)->
-	return crypto.pbkdf2(password, salt, 10000, 64, 'sha1', callback)
-
-keyFn32 = (password, salt, keyLength, callback)->
-	return crypto.pbkdf2(password, salt, 10000, 32, 'sha1', callback)
-
-class AccessTokenEncryptor
-
-	constructor: (settings) ->
-
-		@settings = settings
-		@cipherLabel = @settings.cipherLabel
-		throw Error("cipherLabel must not contain a colon (:)") if @cipherLabel?.match(/:/)
-
-		@cipherPassword = @settings.cipherPasswords[@cipherLabel]
-		throw Error("cipherPassword not set") if not @cipherPassword?
-		throw Error("cipherPassword too short") if @cipherPassword.length < 16
-
-	encryptJson: (json, callback) ->
-		string = JSON.stringify(json)
-		crypto.randomBytes 32, (err, bytes) =>
-			return callback(err) if err
-			salt = bytes.slice(0, 16)
-			iv = bytes.slice(16, 32)
-
-			keyFn32 @cipherPassword, salt, 32, (err, key) =>
-				if err?
-					logger.err err:err, "error getting Fn key"
-					return callback(err)
-
-				cipher = crypto.createCipheriv(ALGORITHM, key, iv)
-				crypted = cipher.update(string, 'utf8', 'base64') + cipher.final('base64')
-
-				callback(null, "#{@cipherLabel}:#{salt.toString('hex')}:#{crypted}:#{iv.toString('hex')}")
-
-	decryptToJson: (encryptedJson, callback) ->
-		[label, salt, cipherText, iv] = encryptedJson.split(':', 4)
-		password = @settings.cipherPasswords[label]
-		return callback(new Error("invalid password")) if not password? or password.length < 16
-
-		if iv
-			@decryptToJsonV2(password, salt, cipherText, iv, callback)
-		else
-			@decryptToJsonV1(password, salt, cipherText, callback)
-
-	decryptToJsonV1: (password, salt, cipherText, callback) ->
-		keyFn password, Buffer.from(salt, 'hex'), (err, key) =>
-			if err?
-				logger.err err:err, "error getting Fn key"
-				return callback(err)
-			decipher = crypto.createDecipher(ALGORITHM, key)
-			dec = decipher.update(cipherText, 'base64', 'utf8') + decipher.final('utf8')
-			try
-				json = JSON.parse(dec)
-			catch e
-				return callback(new Error("error decrypting token"))
-			callback(null, json, true)
-
-	decryptToJsonV2: (password, salt, cipherText, iv, callback) ->
-		keyFn32 password, Buffer.from(salt, 'hex'), 32, (err, key) =>
-			if err?
-				logger.err err:err, "error getting Fn key"
-				return callback(err)
-
-			decipher = crypto.createDecipheriv(ALGORITHM, key, Buffer.from(iv, 'hex'))
-			dec = decipher.update(cipherText, 'base64', 'utf8') + decipher.final('utf8')
-			try
-				json = JSON.parse(dec)
-			catch e
-				return callback(new Error("error decrypting token"))
-			callback(null, json)
-
-module.exports = AccessTokenEncryptor
+/*
+ * decaffeinate suggestions:
+ * DS101: Remove unnecessary use of Array.from
+ * DS102: Remove unnecessary code created because of implicit returns
+ * DS207: Consider shorter variations of null checks
+ * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
+ */
+const crypto = require('crypto');
+
+const ALGORITHM = 'aes-256-ctr';
+
+const keyFn = (password, salt, callback)=> crypto.pbkdf2(password, salt, 10000, 64, 'sha1', callback);
+
+const keyFn32 = (password, salt, keyLength, callback)=> crypto.pbkdf2(password, salt, 10000, 32, 'sha1', callback);
+
+class AccessTokenEncryptor {
+
+	constructor(settings) {
+
+		this.settings = settings;
+		this.cipherLabel = this.settings.cipherLabel;
+		if (this.cipherLabel != null ? this.cipherLabel.match(/:/) : undefined) { throw Error("cipherLabel must not contain a colon (:)"); }
+
+		this.cipherPassword = this.settings.cipherPasswords[this.cipherLabel];
+		if ((this.cipherPassword == null)) { throw Error("cipherPassword not set"); }
+		if (this.cipherPassword.length < 16) { throw Error("cipherPassword too short"); }
+	}
+
+	encryptJson(json, callback) {
+		const string = JSON.stringify(json);
+		return crypto.randomBytes(32, (err, bytes) => {
+			if (err) { return callback(err); }
+			const salt = bytes.slice(0, 16);
+			const iv = bytes.slice(16, 32);
+
+			return keyFn32(this.cipherPassword, salt, 32, (err, key) => {
+				if (err != null) {
+					logger.err({err}, "error getting Fn key");
+					return callback(err);
+				}
+
+				const cipher = crypto.createCipheriv(ALGORITHM, key, iv);
+				const crypted = cipher.update(string, 'utf8', 'base64') + cipher.final('base64');
+
+				return callback(null, `${this.cipherLabel}:${salt.toString('hex')}:${crypted}:${iv.toString('hex')}`);
+			});
+		});
+	}
+
+	decryptToJson(encryptedJson, callback) {
+		const [label, salt, cipherText, iv] = Array.from(encryptedJson.split(':', 4));
+		const password = this.settings.cipherPasswords[label];
+		if ((password == null) || (password.length < 16)) { return callback(new Error("invalid password")); }
+
+		if (iv) {
+			return this.decryptToJsonV2(password, salt, cipherText, iv, callback);
+		} else {
+			return this.decryptToJsonV1(password, salt, cipherText, callback);
+		}
+	}
+
+	decryptToJsonV1(password, salt, cipherText, callback) {
+		return keyFn(password, Buffer.from(salt, 'hex'), (err, key) => {
+			let json;
+			if (err != null) {
+				logger.err({err}, "error getting Fn key");
+				return callback(err);
+			}
+			const decipher = crypto.createDecipher(ALGORITHM, key);
+			const dec = decipher.update(cipherText, 'base64', 'utf8') + decipher.final('utf8');
+			try {
+				json = JSON.parse(dec);
+			} catch (e) {
+				return callback(new Error("error decrypting token"));
+			}
+			return callback(null, json, true);
+		});
+	}
+
+	decryptToJsonV2(password, salt, cipherText, iv, callback) {
+		return keyFn32(password, Buffer.from(salt, 'hex'), 32, (err, key) => {
+			let json;
+			if (err != null) {
+				logger.err({err}, "error getting Fn key");
+				return callback(err);
+			}
+
+			const decipher = crypto.createDecipheriv(ALGORITHM, key, Buffer.from(iv, 'hex'));
+			const dec = decipher.update(cipherText, 'base64', 'utf8') + decipher.final('utf8');
+			try {
+				json = JSON.parse(dec);
+			} catch (e) {
+				return callback(new Error("error decrypting token"));
+			}
+			return callback(null, json);
+		});
+	}
+}
+
+module.exports = AccessTokenEncryptor;