Change way of using salt

Android/APIExample/app/src/main/java/io/agora/api/example/examples/advanced/ChannelEncryption.java

@@ -9,6 +9,7 @@
 
 import android.content.Context;
 import android.os.Bundle;
+import android.util.Base64;
 import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.SurfaceView;
@@ -28,7 +29,6 @@
 import com.yanzhenjie.permission.runtime.Permission;
 
 import java.lang.reflect.Method;
-import java.nio.charset.StandardCharsets;
 
 import io.agora.api.example.MainApplication;
 import io.agora.api.example.R;
@@ -255,7 +255,10 @@ private void enablePacketProcessor(boolean enable) {
     }
 
     private byte[] getKdfSaltFromServer() {
-        return "EncryptionKdfSaltInBase64Strings".getBytes(StandardCharsets.UTF_8);
+        // Salt string should be the output of the following command:
+        // openssl rand -base64 32
+        String saltBase64String = "NiIeJ08AbtcQVjvV+oOEvF/4Dz5dy1CIwa805C8J2w0=";
+        return Base64.decode(saltBase64String, Base64.DEFAULT);
     }
 
     private void joinChannel(String channelId) {

iOS/APIExample-OC/APIExample-OC/Examples/Advanced/StreamEncryption/StreamEncryption.m

@@ -127,10 +127,14 @@ - (void)viewDidLoad {
         [AgoraCustomEncryption registerPacketProcessing:self.agoraKit];
 
     } else {
+        // Salt string should be the output of the following command:
+        // openssl rand -base64 32
+        NSString *saltBase64String = @"NiIeJ08AbtcQVjvV+oOEvF/4Dz5dy1CIwa805C8J2w0=";
+
         AgoraEncryptionConfig *config = [[AgoraEncryptionConfig alloc] init];
         config.encryptionMode = mode;
         config.encryptionKey = secret;
-        config.encryptionKdfSalt = [@"EncryptionKdfSaltInBase64Strings" dataUsingEncoding:(kCFStringEncodingUTF8)];
+        config.encryptionKdfSalt = [[NSData alloc] initWithBase64EncodedString:(saltBase64String) options:(0)];
        int ret = [self.agoraKit enableEncryption:YES encryptionConfig:config];
         if (ret != 0) {
             // for errors please take a look at:

iOS/APIExample/APIExample/Examples/Advanced/StreamEncryption/StreamEncryption.swift

@@ -184,7 +184,10 @@ class StreamEncryptionMain: BaseViewController {
     }
 
     func getEncryptionSaltFromServer() -> Data {
-        return "EncryptionKdfSaltInBase64Strings".data(using: .utf8) ?? Data()
+        // Salt string should be the output of the following command:
+        // openssl rand -base64 32
+        let saltBase64String = "NiIeJ08AbtcQVjvV+oOEvF/4Dz5dy1CIwa805C8J2w0="
+        return Data(base64Encoded: saltBase64String.data(using: .utf8)!)!
     }
 
     override func willMove(toParent parent: UIViewController?) {

macOS/APIExample/Examples/Advanced/StreamEncryption/StreamEncryption.swift

@@ -315,8 +315,10 @@ class StreamEncryption: BaseViewController {
     }
 
     func getEncryptionSaltFromServer() -> Data {
-
-        return "EncryptionKdfSaltInBase64Strings".data(using: .utf8)!
+        // Salt string should be the output of the following command:
+        // openssl rand -base64 32
+        let saltBase64String = "NiIeJ08AbtcQVjvV+oOEvF/4Dz5dy1CIwa805C8J2w0="
+        return Data(base64Encoded: saltBase64String.data(using: .utf8)!)!
     }
 
     func layoutVideos(_ count: Int) {