Add custom script to Encrypt/decript with example using Rhai

Author: aelmizeb

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "rust_crypt"
-version = "1.1.0"
+version = "1.2.0"
 authors = ["Abdellatif EL MIZEB <[email protected]>"]
 edition = "2021"
 include = ["LICENSE", "**/*.rs", "Cargo.toml"]
@@ -26,6 +26,7 @@ log = "0.4.27"
 serde = { version = "1.0.219", features = ["derive"] }
 chrono = "0.4.41"
 rfd = "0.15.3"
+rhai = "1.21.0"
 
 # native:
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]

Cargo.toml

@@ -23,6 +23,37 @@ It allows users to encrypt and decrypt text using configurable logic. Designed t
 - 🌐 Optional Web Interface using Rust + WebAssembly (Yew).
 - 💡 Built with simplicity in mind — ideal for learning how encryption works under the hood.
 
+## 🆕 New Feature: Custom Script Encryption/Decryption
+You can write your own encryption and decryption logic using Rhai, an embedded scripting language for Rust.
+This allows you to define your own custom algorithms directly in the app, by entering a Rhai script for encryption and another for decryption.
+
+Example: Simple String Reversal Script (Encrypt & Decrypt)
+
+```bash
+let result = "";
+let len = text.len();
+while len > 0 {
+    len -= 1;
+    result += text[len..len+1];
+}
+result
+```
+
+This script reverses the input string text by iterating backward over its characters and concatenating them.
+Use the same script for encryption and decryption, as reversing twice returns the original text.
+
+### How to Use:
+
+1- Select Custom Script as the encryption method.
+
+2- Enter your encryption script (e.g., the reversal script above).
+
+3- Enter the same script for decryption.
+
+4- Enter your key if needed (can be ignored for simple scripts).
+
+5- Encrypt and decrypt text or files using your custom logic.
+
 ## 🚀 Getting Started
 
 his project use [eframe](https://github.com/emilk/egui/tree/master/crates/eframe), a framework for writing apps using [egui](https://github.com/emilk/egui/).

README.md

@@ -32,6 +32,7 @@ pub struct TemplateApp {
     encryption_key: String,
     current_view: CurrentView,
     selected_encryption: EncryptionMethod,
+    custom_script: String,
 }
 
 impl Default for TemplateApp {
@@ -42,6 +43,7 @@ impl Default for TemplateApp {
             encryption_key: "defaultkey".to_owned(),
             current_view: CurrentView::EncryptText,
             selected_encryption: EncryptionMethod::Caesar,
+            custom_script: String::new(),
         }
     }
 }

src/app.rs

@@ -0,0 +1,34 @@
+use rhai::{Engine, Scope};
+
+pub fn custom_encrypt(script: &str, text: &str, key: &str) -> String {
+    let engine = Engine::new();
+    let mut scope = Scope::new();
+
+    scope.push("text", text.to_string());
+    scope.push("key", key.to_string());
+
+    match engine.eval_with_scope::<String>(&mut scope, script) {
+        Ok(result) => result,
+        Err(err) => format!("Error: {}", err),
+    }
+}
+
+pub fn custom_encrypt_file(input: &str, key: &str, script: &str) -> String {
+    custom_encrypt(script, input, key)
+}
+
+pub fn custom_decrypt(input: &str, key: &str, script: &str) -> String {
+    let engine = Engine::new();
+    let mut scope = Scope::new();
+    scope.push("text", input.to_string());
+    scope.push("key", key.to_string());
+
+    match engine.eval_with_scope::<String>(&mut scope, script) {
+        Ok(result) => result,
+        Err(e) => format!("❌ Script Error: {}", e),
+    }
+}
+
+pub fn custom_decrypt_file(input: &str, key: &str, script: &str) -> String {
+    custom_decrypt(input, key, script)
+}

src/app/encryption/custom.rs

@@ -1,13 +1,16 @@
 pub mod caesar;
 pub mod xor;
+pub mod custom;
 
 pub use caesar::{caesar_encrypt, caesar_decrypt, caesar_encrypt_file};
 pub use xor::{xor_encrypt, xor_decrypt, xor_encrypt_file};
+pub use custom::{custom_encrypt, custom_encrypt_file, custom_decrypt, custom_decrypt_file};
 
 use serde::{Deserialize, Serialize};
 
 #[derive(Clone, Copy, PartialEq, Serialize, Deserialize)]
 pub enum EncryptionMethod {
     Caesar,
     XOR,
+    Custom,
 }

src/app/encryption/mod.rs

@@ -2,7 +2,7 @@ use crate::app::{encryption, TemplateApp};
 use egui::{Ui, ComboBox, RichText, TextEdit};
 use rfd::FileDialog;
 use std::fs;
-use encryption::{EncryptionMethod, caesar_decrypt, xor_decrypt};
+use encryption::{EncryptionMethod, caesar_decrypt, xor_decrypt, custom_decrypt_file};
 
 pub fn decrypt_file_view(ui: &mut Ui, app: &mut TemplateApp) {
     ui.heading(RichText::new("📂 Decrypt File").size(20.0).strong());
@@ -27,21 +27,38 @@ pub fn decrypt_file_view(ui: &mut Ui, app: &mut TemplateApp) {
                 .selected_text(match app.selected_encryption {
                     EncryptionMethod::Caesar => "Caesar Cipher",
                     EncryptionMethod::XOR => "XOR Cipher",
+                    EncryptionMethod::Custom => "Custom Script",
                 })
                 .show_ui(ui, |ui| {
                     ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::Caesar, "Caesar Cipher");
                     ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::XOR, "XOR Cipher");
+                    ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::Custom, "Custom Script");
                 });
 
             ui.add_space(10.0);
 
+            // Show custom script input only if custom encryption selected
+            if app.selected_encryption == EncryptionMethod::Custom {
+                ui.label(RichText::new("✍️ Custom Decryption Script (Rhai)").strong());
+                ui.add(
+                    TextEdit::multiline(&mut app.custom_script)
+                        .desired_rows(10)
+                        .desired_width(ui.available_width())
+                        .hint_text("Enter your Rhai script here.\nUse variables 'text' for input and 'key' for the encryption key."),
+                );
+                ui.add_space(10.0);
+            }
+
             // File Selection Button
             if ui.button("📁 Select File to Decrypt").clicked() {
                 if let Some(path) = FileDialog::new().pick_file() {
                     if let Ok(data) = fs::read_to_string(&path) {
                         let decrypted = match app.selected_encryption {
                             EncryptionMethod::Caesar => caesar_decrypt(&data, &app.encryption_key),
                             EncryptionMethod::XOR => xor_decrypt(&data, &app.encryption_key),
+                            EncryptionMethod::Custom => {
+                                custom_decrypt_file(&data, &app.encryption_key, &app.custom_script)
+                            }
                         };
 
                         let output_path = path.with_file_name(format!(

src/app/views/decrypt_file.rs

@@ -1,7 +1,6 @@
 use crate::app::{encryption, TemplateApp};
 use egui::{Ui, ComboBox, RichText, TextEdit};
-use encryption::{EncryptionMethod, caesar_decrypt, xor_decrypt};
-
+use encryption::{EncryptionMethod, caesar_decrypt, xor_decrypt, custom_decrypt};
 
 pub fn decrypt_text_view(ui: &mut Ui, app: &mut TemplateApp) {
     ui.heading(RichText::new("🔓 Decrypt Text").size(20.0).strong());
@@ -26,14 +25,28 @@ pub fn decrypt_text_view(ui: &mut Ui, app: &mut TemplateApp) {
                 .selected_text(match app.selected_encryption {
                     EncryptionMethod::Caesar => "Caesar Cipher",
                     EncryptionMethod::XOR => "XOR Cipher",
+                    EncryptionMethod::Custom => "Custom Script",
                 })
                 .show_ui(ui, |ui| {
                     ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::Caesar, "Caesar Cipher");
                     ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::XOR, "XOR Cipher");
+                    ui.selectable_value(&mut app.selected_encryption, EncryptionMethod::Custom, "Custom Script");
                 });
 
             ui.add_space(10.0);
 
+            // Custom Script Input (only if selected)
+            if app.selected_encryption == EncryptionMethod::Custom {
+                ui.label(RichText::new("📜 Custom Rhai Script").strong());
+                ui.add(
+                    TextEdit::multiline(&mut app.custom_script)
+                        .hint_text("Example: text.replace(\" 🔐\", \"\")")
+                        .desired_rows(6)
+                        .desired_width(ui.available_width()),
+                );
+                ui.add_space(10.0);
+            }
+
             // Input Text
             ui.label(RichText::new("📝 Encrypted Input").strong());
             ui.add(
@@ -49,6 +62,7 @@ pub fn decrypt_text_view(ui: &mut Ui, app: &mut TemplateApp) {
                 app.output_text = match app.selected_encryption {
                     EncryptionMethod::Caesar => caesar_decrypt(&app.input_text, &app.encryption_key),
                     EncryptionMethod::XOR => xor_decrypt(&app.input_text, &app.encryption_key),
+                    EncryptionMethod::Custom => custom_decrypt(&app.input_text, &app.encryption_key, &app.custom_script),
                 };
             }