Convert crypto.ts to use classes

lawrence-forooghian · lawrence-forooghian · commit fc5ccfd4b58c · 2023-05-16T17:34:12.000-03:00
wip convert Node Crypto to class haven't formatted this — will do once contents of class are correct Use of `satisfies` comes from suggestion in [1]. [1] "Allow specifying interface implements clauses for the static side of classes": microsoft/TypeScript#33892 wip convert node crypto CBCCipher to class This concludes the conversion, started in 18ba2a0, of the nodejs platform’s crypto.js file to TypeScript. Convert web’s crypto.ts to use classes TODO need to format, but first document what I did
diff --git a/src/platform/nodejs/lib/util/crypto.ts b/src/platform/nodejs/lib/util/crypto.ts
@@ -4,7 +4,7 @@ import Platform from '../../../../common/platform';
 import crypto from 'crypto';
 import ErrorInfo from '../../../../common/lib/types/errorinfo';
 import * as API from '../../../../../ably';
-import { IGetCipherParams, CryptoTypes } from '../../../../common/types/ICrypto';
+import ICrypto, { IGetCipherParams, CryptoTypes } from '../../../../common/types/ICrypto';
 import ICipher from '../../../../common/types/ICipher';
 import { Cipher as NodeCipher, CipherKey as NodeCipherKey } from 'crypto';
 import { Bufferlike, Output as BufferUtilsOutput, WordArrayLike } from './bufferutils';
@@ -88,18 +88,6 @@ var Crypto = (function () {
     return typeof bufferOrString == 'string' ? Buffer.from(bufferOrString, 'binary') : bufferOrString;
   }
 
-  interface _CipherParams extends API.Types.CipherParams {
-    algorithm: string;
-    keyLength: number;
-    mode: string;
-    key: NodeCipherKey;
-    iv: unknown;
-  }
-
-  interface _CipherParamsConstructor {
-    new (algorithm: string, keyLength: number, mode: string, key: NodeCipherKey): _CipherParams;
-  }
-
   /**
    * A class encapsulating the client-specifiable parameters for
    * the cipher.
@@ -110,8 +98,14 @@ var Crypto = (function () {
    * Clients may instance a CipherParams directly and populate it, or may
    * query the implementation to obtain a default system CipherParams.
    */
-  const CipherParams = function (
-    this: _CipherParams,
+  class CipherParams implements API.Types.CipherParams {
+    algorithm: string;
+    keyLength: number;
+    mode: string;
+    key: NodeCipherKey;
+    iv: unknown;
+
+    constructor(
     algorithm: string,
     keyLength: number,
     mode: string,
@@ -122,7 +116,8 @@ var Crypto = (function () {
     this.mode = mode;
     this.key = key;
     this.iv = null;
-  } as unknown as _CipherParamsConstructor;
+  }
+  }
 
   function isInstCipherParams(
     params: API.Types.CipherParams | API.Types.CipherParamOptions
@@ -150,9 +145,9 @@ var Crypto = (function () {
    * concatenated with the resulting raw ciphertext to construct the "ciphertext"
    * data passed to the recipient.
    */
-  function Crypto() {}
+  class Crypto {
 
-  Crypto.CipherParams = CipherParams;
+  static CipherParams = CipherParams;
 
   /**
    * Obtain a complete CipherParams instance from the provided params, filling
@@ -163,7 +158,7 @@ var Crypto = (function () {
    * base64-encoded string. May optionally also contain: algorithm (defaults to
    * AES), mode (defaults to 'cbc')
    */
-  Crypto.getDefaultParams = function (params: API.Types.CipherParamOptions) {
+  static getDefaultParams(params: API.Types.CipherParamOptions) {
     var key: Buffer;
 
     if (!params.key) {
@@ -198,15 +193,15 @@ var Crypto = (function () {
 
     validateCipherParams(cipherParams);
     return cipherParams;
-  };
+  }
 
   /**
    * Generate a random encryption key from the supplied keylength (or the
    * default keyLength if none supplied) as a Buffer
    * @param keyLength (optional) the required keyLength in bits
    * @param callback (optional) (err, key)
    */
-  Crypto.generateRandomKey = function (keyLength?: number, callback?: API.Types.StandardCallback<API.Types.CipherKey>) {
+  static generateRandomKey(keyLength?: number, callback?: API.Types.StandardCallback<API.Types.CipherKey>) {
     if (arguments.length == 1 && typeof keyLength == 'function') {
       callback = keyLength;
       keyLength = undefined;
@@ -219,49 +214,43 @@ var Crypto = (function () {
     generateRandom((keyLength || DEFAULT_KEYLENGTH) / 8, (err, buf) => {
       callback!(err ? ErrorInfo.fromValues(err) : null, buf);
     });
-  };
+  }
 
   /**
    * Internal; get a ChannelCipher instance based on the given cipherParams
    * @param params either a CipherParams instance or some subset of its
    * fields that includes a key
    */
-  Crypto.getCipher = function (params: IGetCipherParams<IV>) {
-    var cipherParams = isInstCipherParams(params) ? (params as _CipherParams) : Crypto.getDefaultParams(params);
+  static getCipher(params: IGetCipherParams<IV>) {
+    var cipherParams = isInstCipherParams(params) ? (params as CipherParams) : Crypto.getDefaultParams(params);
 
     var iv = params.iv || generateRandom(DEFAULT_BLOCKLENGTH);
     return {
       cipherParams: cipherParams,
       cipher: new CBCCipher(cipherParams, iv),
     };
-  };
+  }
 
-  interface _CBCCipher extends ICipher<InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext> {
+  }
+
+  Crypto satisfies ICrypto<IV, InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext>;
+
+  class CBCCipher implements ICipher<InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext> {
     algorithm: string;
     key: NodeCipherKey;
     iv: Buffer | null;
     encryptCipher: NodeCipher;
     blockLength: number;
-    getIv: () => Buffer;
-  }
 
-  interface _CBCCipherConstructor {
-    new (params: _CipherParams, iv: Buffer): _CBCCipher;
-  }
-
-  const CBCCipher = function CBCCipher(this: _CBCCipher, params: _CipherParams, iv: Buffer) {
+  constructor(params: CipherParams, iv: Buffer) {
     this.algorithm = params.algorithm + '-' + String(params.keyLength) + '-' + params.mode;
     this.key = params.key;
     this.iv = iv;
     this.encryptCipher = crypto.createCipheriv(this.algorithm, this.key, this.iv);
     this.blockLength = this.iv.length;
-  } as unknown as _CBCCipherConstructor;
+  }
 
-  CBCCipher.prototype.encrypt = function (
-    this: _CBCCipher,
-    plaintext: InputPlaintext,
-    callback: (error: Error | null, data: OutputCiphertext | null) => void
-  ) {
+  encrypt(plaintext: InputPlaintext, callback: (error: Error | null, data: OutputPlaintext | null) => void) {
     Logger.logAction(Logger.LOG_MICRO, 'CBCCipher.encrypt()', '');
     var plaintextBuffer = Platform.BufferUtils.toBuffer(plaintext);
     var plaintextLength = plaintextBuffer.length,
@@ -272,18 +261,18 @@ var Crypto = (function () {
     );
     var ciphertext = Buffer.concat([iv, toBuffer(cipherOut)]);
     return callback(null, ciphertext);
-  };
+  }
 
-  CBCCipher.prototype.decrypt = function (this: _CBCCipher, ciphertext: InputCiphertext) {
+  decrypt(ciphertext: InputCiphertext) {
     var blockLength = this.blockLength,
       decryptCipher = crypto.createDecipheriv(this.algorithm, this.key, ciphertext.slice(0, blockLength)),
       plaintext = toBuffer(decryptCipher.update(ciphertext.slice(blockLength))),
       final = decryptCipher.final();
     if (final && final.length) plaintext = Buffer.concat([plaintext, toBuffer(final)]);
     return plaintext;
-  };
+  }
 
-  CBCCipher.prototype.getIv = function (this: _CBCCipher) {
+  getIv() {
     if (this.iv) {
       var iv = this.iv;
       this.iv = null;
@@ -295,7 +284,8 @@ var Crypto = (function () {
      * sets a new iv (= aes(randomBlock XOR lastCipherText)) as well as
      * returning it */
     return toBuffer(this.encryptCipher.update(randomBlock));
-  };
+  }
+  }
 
   return Crypto;
 })();
diff --git a/src/platform/web/lib/util/crypto.ts b/src/platform/web/lib/util/crypto.ts
@@ -5,7 +5,7 @@ import Platform from '../../../../common/platform';
 import Logger from '../../../../common/lib/util/logger';
 import ErrorInfo from 'common/lib/types/errorinfo';
 import * as API from '../../../../../ably';
-import { IGetCipherParams, CryptoTypes } from '../../../../common/types/ICrypto';
+import ICrypto, { IGetCipherParams, CryptoTypes } from '../../../../common/types/ICrypto';
 import ICipher from '../../../../common/types/ICipher';
 import { Bufferlike, Output as BufferUtilsOutput } from './bufferutils';
 
@@ -129,17 +129,6 @@ var Crypto = (function () {
     return params instanceof CipherParams;
   }
 
-  interface _CipherParams extends API.Types.CipherParams {
-    algorithm: string;
-    keyLength: number;
-    mode: string;
-    key: WordArray;
-  }
-
-  interface _CipherParamsConstructor {
-    new (algorithm: string, keyLength: number, mode: string, key: WordArray): _CipherParams;
-  }
-
   /**
    * A class encapsulating the client-specifiable parameters for
    * the cipher.
@@ -151,8 +140,13 @@ var Crypto = (function () {
    * Crypto.getDefaultParams helper, which will fill in any fields not supplied
    * with default values and validation the result.
    */
-  const CipherParams = function (
-    this: _CipherParams,
+  class CipherParams implements API.Types.CipherParams {
+    algorithm: string;
+    keyLength: number;
+    mode: string;
+    key: WordArray;
+
+    constructor(
     algorithm: string,
     keyLength: number,
     mode: string,
@@ -162,7 +156,8 @@ var Crypto = (function () {
     this.keyLength = keyLength;
     this.mode = mode;
     this.key = key;
-  } as unknown as _CipherParamsConstructor;
+  }
+  }
 
   /**
    * Utility classes and interfaces for message payload encryption.
@@ -182,9 +177,9 @@ var Crypto = (function () {
    * concatenated with the resulting raw ciphertext to construct the "ciphertext"
    * data passed to the recipient.
    */
-  function Crypto() {}
+  class Crypto {
 
-  Crypto.CipherParams = CipherParams;
+  static CipherParams = CipherParams;
 
   /**
    * Obtain a complete CipherParams instance from the provided params, filling
@@ -195,7 +190,7 @@ var Crypto = (function () {
    * base64-encoded string. May optionally also contain: algorithm (defaults to
    * AES), mode (defaults to 'cbc')
    */
-  Crypto.getDefaultParams = function (params: API.Types.CipherParamOptions) {
+  static getDefaultParams(params: API.Types.CipherParamOptions) {
     var key: WordArray;
 
     if (!params.key) {
@@ -224,15 +219,15 @@ var Crypto = (function () {
 
     validateCipherParams(cipherParams);
     return cipherParams;
-  };
+  }
 
   /**
    * Generate a random encryption key from the supplied keylength (or the
    * default keyLength if none supplied) as a CryptoJS WordArray
    * @param keyLength (optional) the required keyLength in bits
    * @param callback (optional) (err, key)
    */
-  Crypto.generateRandomKey = function (keyLength?: number, callback?: API.Types.StandardCallback<API.Types.CipherKey>) {
+  static generateRandomKey(keyLength?: number, callback?: API.Types.StandardCallback<API.Types.CipherKey>) {
     if (arguments.length == 1 && typeof keyLength == 'function') {
       callback = keyLength;
       keyLength = undefined;
@@ -245,38 +240,35 @@ var Crypto = (function () {
     generateRandom((keyLength || DEFAULT_KEYLENGTH) / 8, (err, buf) => {
       callback!(err ? ErrorInfo.fromValues(err) : null, buf);
     });
-  };
+  }
 
   /**
    * Internal; get a ChannelCipher instance based on the given cipherParams
    * @param params either a CipherParams instance or some subset of its
    * fields that includes a key
    */
-  Crypto.getCipher = function (params: IGetCipherParams<IV>) {
-    var cipherParams = isCipherParams(params) ? (params as _CipherParams) : Crypto.getDefaultParams(params);
+  static getCipher(params: IGetCipherParams<IV>) {
+    var cipherParams = isCipherParams(params) ? (params as CipherParams) : Crypto.getDefaultParams(params);
     var iv = params.iv != null ? Platform.BufferUtils.toWordArray(params.iv) : null;
 
     return {
       cipherParams: cipherParams,
       cipher: new CBCCipher(cipherParams, DEFAULT_BLOCKLENGTH_WORDS, iv),
     };
-  };
+  }
+}
 
-  interface _CBCCipher extends ICipher<InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext> {
+  Crypto satisfies ICrypto<IV, InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext>;
+
+  class CBCCipher implements ICipher<InputPlaintext, OutputCiphertext, InputCiphertext, OutputPlaintext> {
     algorithm: string;
     cjsAlgorithm: 'AES';
     key: WordArray;
     iv: WordArray | null;
     blockLengthWords: number;
-    encryptCipher: ReturnType<typeof CryptoJS.algo.AES.createEncryptor> | null;
-    getIv: (callback: (error: Error | null, iv: WordArray | null) => void) => void;
-  }
-
-  interface _CBCCipherConstructor {
-    new (params: _CipherParams, blockLengthWords: number, iv: WordArray | null): _CBCCipher;
-  }
+    encryptCipher: ReturnType<typeof CryptoJS.algo.AES.createEncryptor> | null;  
 
-  const CBCCipher = function (this: _CBCCipher, params: _CipherParams, blockLengthWords: number, iv: WordArray | null) {
+    constructor(params: CipherParams, blockLengthWords: number, iv: WordArray | null) {
     this.algorithm = params.algorithm + '-' + String(params.keyLength) + '-' + params.mode;
     const cjsAlgorithm = params.algorithm.toUpperCase().replace(/-\d+$/, '');
     if (cjsAlgorithm != 'AES') {
@@ -287,10 +279,9 @@ var Crypto = (function () {
     this.iv = iv ? Platform.BufferUtils.toWordArray(iv).clone() : null;
     this.blockLengthWords = blockLengthWords;
     this.encryptCipher = null;
-  } as unknown as _CBCCipherConstructor;
+  }
 
-  CBCCipher.prototype.encrypt = function (
-    this: _CBCCipher,
+  encrypt(
     plaintext: InputPlaintext,
     callback: (error: Error | null, data: OutputPlaintext | null) => void
   ) {
@@ -332,9 +323,9 @@ var Crypto = (function () {
     } else {
       then();
     }
-  };
+  }
 
-  CBCCipher.prototype.decrypt = function (this: _CBCCipher, ciphertext: InputCiphertext) {
+  decrypt(ciphertext: InputCiphertext) {
     Logger.logAction(Logger.LOG_MICRO, 'CBCCipher.decrypt()', '');
     ciphertext = Platform.BufferUtils.toWordArray(ciphertext);
     var blockLengthWords = this.blockLengthWords,
@@ -348,12 +339,9 @@ var Crypto = (function () {
     decryptCipher.reset();
     if (epilogue && epilogue.sigBytes) plaintext.concat(epilogue);
     return plaintext;
-  };
+  }
 
-  CBCCipher.prototype.getIv = function (
-    this: _CBCCipher,
-    callback: (error: Error | null, iv: WordArray | null) => void
-  ) {
+  getIv(callback: (error: Error | null, iv: WordArray | null) => void) {
     if (this.iv) {
       var iv = this.iv;
       this.iv = null;
@@ -372,7 +360,8 @@ var Crypto = (function () {
       }
       callback(null, self.encryptCipher!.process(randomBlock!));
     });
-  };
+  }
+  }
 
   return Crypto;
 })();
