diff --git a/packages/core/src/utils/crypto/abstract.ts b/packages/core/src/utils/crypto/abstract.ts
index 943b0d83..1ad0690f 100644
--- a/packages/core/src/utils/crypto/abstract.ts
+++ b/packages/core/src/utils/crypto/abstract.ts
@@ -4,11 +4,13 @@ import { factorizePQSync } from './factorization'
 
 export interface IEncryptionScheme {
     encrypt(data: Buffer): MaybeAsync<Buffer>
+
     decrypt(data: Buffer): MaybeAsync<Buffer>
 }
 
 export interface IHashMethod {
     update(data: Buffer): MaybeAsync<void>
+
     digest(): MaybeAsync<Buffer>
 }
 
@@ -16,17 +18,24 @@ export interface ICryptoProvider {
     initialize?(): MaybeAsync<void>
 
     sha1(data: Buffer): MaybeAsync<Buffer>
+
     sha256(data: Buffer): MaybeAsync<Buffer>
+
     pbkdf2(
         password: Buffer,
         salt: Buffer,
-        iterations: number
+        iterations: number,
+        keylen?: number, // = 64
+        algo?: string // sha1 or sha512 (default sha512)
     ): MaybeAsync<Buffer>
+
     hmacSha256(data: Buffer, key: Buffer): MaybeAsync<Buffer>
 
     // in telegram, iv is always either used only once, or is the same for all calls for the key
     createAesCtr(key: Buffer, iv: Buffer, encrypt: boolean): IEncryptionScheme
+
     createAesIge(key: Buffer, iv: Buffer): IEncryptionScheme
+
     createAesEcb(key: Buffer): IEncryptionScheme
 
     createMd5(): IHashMethod
@@ -53,13 +62,12 @@ export abstract class BaseCryptoProvider implements ICryptoProvider {
 
     abstract createAesEcb(key: Buffer): IEncryptionScheme
 
-    // algo: sha1 or sha512 (default sha512)
     abstract pbkdf2(
         password: Buffer,
         salt: Buffer,
         iterations: number,
         keylen?: number, // = 64
-        algo?: string
+        algo?: string // sha1 or sha512 (default sha512)
     ): MaybeAsync<Buffer>
 
     abstract sha1(data: Buffer): MaybeAsync<Buffer>