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+# Encryption and Decryption using Node.js
+
+This code provides a simple way to encrypt and decrypt text using the Advanced Encryption Standard (AES) algorithm in Cipher Block Chaining (CBC) mode with Node.js's `crypto` module.
+
+## Pre requisites
+
+Before using this code, make sure you have Node.js installed on your system.
+
+## Usage
+
+1. **Import the Module**
+
+   First, import the `encrypt` and `decrypt` functions from the module in your Node.js project.
+
+   ```javascript
+   const crypto = require('./crypto');
+   ```
+
+2. **Set Encryption Parameters**
+
+   Modify the following constants in your code with your own values:
+   
+   - `CHAVE`: A 32-character encryption key.
+   - `IV`: A 16-character initialization vector.
+   - `ALGORITMO`: The encryption algorithm, which is set to "aes-256-cbc" by default. You can change it if needed.
+   - `METODO_CRIPTOGRAFIA` and `METODO_DESCRIPTOGRAFIA`: The methods used for encoding the output. They are set to 'hex' by default.
+
+3. **Encrypt Text**
+
+   To encrypt a piece of text, call the `encrypt` function and pass the text as a parameter.
+
+   ```javascript
+   const textToEncrypt = 'This is a secret message';
+   const encryptedText = crypto.encrypt(textToEncrypt);
+   ```
+
+4. **Decrypt Text**
+
+   To decrypt the encrypted text, call the `decrypt` function and pass the encrypted text as a parameter.
+
+   ```javascript
+   const decryptedText = crypto.decrypt(encryptedText);
+   ```
+
+5. **Complete Example**
+
+   Here's a complete example of how to use the code:
+
+   ```javascript
+   const crypto = require('./crypto');
+
+   const CHAVE = 'bf3c199c2470cb477d907b1e0917c17e';
+   const IV = '5183666c72eec9e4';
+
+   // Encrypt
+   const textToEncrypt = 'This is a secret message';
+   const encryptedText = crypto.encrypt(textToEncrypt);
+   console.log('Encrypted:', encryptedText);
+
+   // Decrypt
+   const decryptedText = crypto.decrypt(encryptedText);
+   console.log('Decrypted:', decryptedText);
+   ```
+
+## Security Note
+
+Make sure to keep your encryption key (`CHAVE`) and initialization vector (`IV`) secret and secure, as they are critical for the security of your encrypted data.
+
+---
+
+Feel free to replace the placeholders with your actual values and use this README as a guide to integrate encryption and decryption into your Node.js project.
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