MAIN CODE PUSHED ON MASTER BRANCH - NEED TO WORK ON ENCRYPTION AND DECRYPTION

src/main/java/com/skycrate/backend/skycrateBackend/controller/HDFScontroller.java

@@ -1,11 +1,17 @@
 package com.skycrate.backend.skycrateBackend.controller;
 
+import com.skycrate.backend.skycrateBackend.config.HDFSConfig;
 import com.skycrate.backend.skycrateBackend.dto.ResponseDTO;
+import com.skycrate.backend.skycrateBackend.models.User;
+import com.skycrate.backend.skycrateBackend.repository.UserRepository;
 import com.skycrate.backend.skycrateBackend.services.EncryptionUtil;
 import com.skycrate.backend.skycrateBackend.services.HDFSOperations;
 import com.skycrate.backend.skycrateBackend.utils.KeyUtil;
+import com.skycrate.backend.skycrateBackend.utils.RSAKeyUtil;
+import org.apache.hadoop.fs.FileSystem;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.multipart.MultipartFile;
@@ -15,6 +21,7 @@ import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.nio.file.StandardCopyOption;
+import java.security.NoSuchAlgorithmException;
 import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.util.List;
@@ -22,6 +29,11 @@ import java.util.List;
 import org.springframework.core.io.FileSystemResource; // For FileSystemResource
 import org.springframework.core.io.Resource; // For Resource
 import org.springframework.http.HttpHeaders; // For HttpHeaders
+
+import javax.crypto.Cipher;
+import javax.crypto.KeyGenerator;
+import javax.crypto.SecretKey;
+import javax.crypto.spec.SecretKeySpec;
 import java.io.File; // For java.io.File
 
 import static com.skycrate.backend.skycrateBackend.utils.KeyUtil.getPrivateKeyForUser;
@@ -33,6 +45,10 @@ public class HDFScontroller {
 
     private final HDFSOperations hdfsOperations;
 
+    @Autowired
+    private UserRepository userRepository;
+
+
     @Autowired
     public HDFScontroller(HDFSOperations hdfsOperations) {
         this.hdfsOperations = hdfsOperations;
@@ -57,12 +73,19 @@ public class HDFScontroller {
             @RequestParam String uploadedFileName,
             @RequestParam String username) {
         try {
-            // Save file locally first
+            // Retrieve the user from the database using the username
-            String localPath = saveFileLocally(file);
+            User user = userRepository.findByUsername(username).orElseThrow(() -> new RuntimeException("User not found"));
-            System.out.println("File saved locally at: " + localPath);
+
+            // Get the public key from the user entity
+            byte[] publicKeyBytes = user.getPublicKey();
+            PublicKey publicKey = RSAKeyUtil.getPublicKeyFromBytes(publicKeyBytes);
+
+            // Encrypt the file content using the public key
+            byte[] encryptedData = encryptFile(file, publicKey);
+
+            // Upload the encrypted file to HDFS
+            hdfsOperations.uploadFile(encryptedData, hdfsPath, uploadedFileName, username);
 
-            // Upload file to HDFS
-            hdfsOperations.uploadFile(localPath, hdfsPath, uploadedFileName, username);
             return new ResponseDTO("File uploaded successfully", true);
         } catch (IOException e) {
             e.printStackTrace();
@@ -73,6 +96,41 @@ public class HDFScontroller {
         }
     }
 
+    // Helper method to encrypt the file content using RSA encryption
+    private byte[] encryptFile(MultipartFile file, PublicKey publicKey) throws Exception {
+        // Step 1: Generate a random AES key
+        SecretKey aesKey = generateAESKey();
+
+        // Step 2: Encrypt the file data using AES
+        Cipher aesCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+        aesCipher.init(Cipher.ENCRYPT_MODE, aesKey);
+        byte[] fileData = file.getBytes();
+        byte[] encryptedData = aesCipher.doFinal(fileData);
+
+        // Step 3: Encrypt the AES key with RSA
+        Cipher rsaCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+        rsaCipher.init(Cipher.ENCRYPT_MODE, publicKey);
+        byte[] encryptedAesKey = rsaCipher.doFinal(aesKey.getEncoded());
+
+        // Step 4: Combine the encrypted AES key and the encrypted data
+        byte[] combined = new byte[4 + encryptedAesKey.length + encryptedData.length];
+        combined[0] = (byte) (encryptedAesKey.length >> 24);
+        combined[1] = (byte) (encryptedAesKey.length >> 16);
+        combined[2] = (byte) (encryptedAesKey.length >> 8);
+        combined[3] = (byte) encryptedAesKey.length;
+
+        System.arraycopy(encryptedAesKey, 0, combined, 4, encryptedAesKey.length);
+        System.arraycopy(encryptedData, 0, combined, 4 + encryptedAesKey.length, encryptedData.length);
+
+        return combined;
+    }
+
+    // Generate a random AES key
+    private SecretKey generateAESKey() throws NoSuchAlgorithmException {
+        KeyGenerator keyGen = KeyGenerator.getInstance("AES");
+        keyGen.init(256); // Use 256 bits for AES
+        return keyGen.generateKey();
+    }
 
     private String saveFileLocally(MultipartFile file) throws IOException {
         // Create a temporary directory if it doesn't exist
@@ -89,36 +147,108 @@ public class HDFScontroller {
         return path.toString(); // Return the local path for further processing
     }
 
-
     @PostMapping("/downloadFile")
-    public ResponseEntity<?> downloadFile(
+    public ResponseEntity<Resource> downloadFile(
-            @RequestParam String hdfsPath,
+            @RequestParam String hdfsEncPath,
             @RequestParam String username) {
         try {
-            // Define a temporary local path to download the file
+            // Extract the file name and extension
-            String localPath = "/app/tmp/downloaded/" + new File(hdfsPath).getName(); // Adjust the path as needed
+            String encFileName = new File(hdfsEncPath).getName();
+            String originalFileName = encFileName.replace(".enc", "");
+            String fileExtension = originalFileName.substring(originalFileName.lastIndexOf(".") + 1);
 
-            // Download the file from HDFS to the local path
+            // Define local decrypted file path
-            hdfsOperations.downloadFile(hdfsPath, localPath, username);
+            String localDecryptedPath = "/SkyCrate/downloaded/" + originalFileName;
 
-            // Create a File object for the downloaded file
+            // Define HDFS paths for encrypted file
-            File file = new File(localPath);
+            String encFilePath = "/SkyCrate/downloaded/" + encFileName;
-            if (!file.exists()) {
+
-                return ResponseEntity.status(HttpStatus.NOT_FOUND)
+            FileSystem fs = HDFSConfig.getHDFS();
-                        .body(new ResponseDTO("File not found", false));
+
+            // Download encrypted file from HDFS
+            fs.copyToLocalFile(new org.apache.hadoop.fs.Path(hdfsEncPath), new org.apache.hadoop.fs.Path(encFilePath));
+
+            // Retrieve the RSA private key for the user
+            User user = userRepository.findByUsername(username)
+                    .orElseThrow(() -> new RuntimeException("User not found"));
+            PrivateKey privateKey = RSAKeyUtil.getPrivateKeyFromBytes(user.getPrivateKey());
+
+            // Read the encrypted file content
+            byte[] encryptedFileContent = Files.readAllBytes(Paths.get(encFilePath));
+
+            // Step 1: Extract the AES key length from the combined data
+            int aesKeyLength = ((encryptedFileContent[0] & 0xFF) << 24) |
+                    ((encryptedFileContent[1] & 0xFF) << 16) |
+                    ((encryptedFileContent[2] & 0xFF) << 8) |
+                    (encryptedFileContent[3] & 0xFF);
+
+            // Step 2: Extract the encrypted AES key and encrypted data
+            byte[] encryptedAesKey = new byte[aesKeyLength];
+            byte[] encryptedData = new byte[encryptedFileContent.length - 4 - aesKeyLength];
+
+            System.arraycopy(encryptedFileContent, 4, encryptedAesKey, 0, aesKeyLength);
+            System.arraycopy(encryptedFileContent, 4 + aesKeyLength, encryptedData, 0, encryptedData.length);
+
+            // Step 3: Decrypt the AES key using RSA
+            Cipher rsaCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
+            rsaCipher.init(Cipher.DECRYPT_MODE, privateKey);
+            byte[] aesKeyBytes = rsaCipher.doFinal(encryptedAesKey);
+
+            // Create the AES key
+            SecretKey aesKey = new SecretKeySpec(aesKeyBytes, "AES");
+
+            // Step 4: Decrypt the data using AES
+            Cipher aesCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
+            aesCipher.init(Cipher.DECRYPT_MODE, aesKey);
+
+            // Decrypt the file content using the provided decrypt method
+//            byte[] decryptedFileContent = RSAKeyUtil.decrypt(encryptedFileContent, privateKey);
+            byte[] decryptedFileContent = aesCipher.doFinal(encryptedData);
+
+            // Write the decrypted content to the original file
+            Files.write(Paths.get(localDecryptedPath + "." + fileExtension), decryptedFileContent);
+
+
+            // Log the file creation
+            if (Files.exists(Paths.get(localDecryptedPath + "." + fileExtension))) {
+                System.out.println("File created successfully at: " + localDecryptedPath + "." + fileExtension);
+            } else {
+                System.out.println("Failed to create file at: " + localDecryptedPath + "." + fileExtension);
             }
 
-            // Create a Resource from the file
+            // Create the decrypted file resource
-            Resource resource = new FileSystemResource(file);
+            File decryptedFile = new File(localDecryptedPath + "." + fileExtension);
+            Resource resource = new FileSystemResource(decryptedFile);
+
+            // Return the file as a response
             return ResponseEntity.ok()
-                    .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + resource.getFilename() + "\"")
+                    .contentLength(decryptedFile.length())
+                    .contentType(MediaType.APPLICATION_OCTET_STREAM)
+                    .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + decryptedFile.getName() + "\"")
                     .body(resource);
+
         } catch (Exception e) {
+            e.printStackTrace();
             return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
-                    .body(new ResponseDTO("Failed to download file: " + e.getMessage(), false));
+                    .body(null);
         }
     }
 
+
+    public void initializeKeysForUser(String username) {
+        try {
+            // Check if the public key file exists
+            Path publicKeyPath = Paths.get("C:\\Users\\sonal\\OneDrive\\Desktop\\SkyCrate\\Skycrate\\keys", username + "_public.key");
+            if (!Files.exists(publicKeyPath)) {
+                // Generate and store keys if they do not exist
+                KeyUtil.generateAndStoreKeyPair(username);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+
     @DeleteMapping("/deleteFile")
     public ResponseDTO deleteFile(@RequestParam String hdfsPath) {
         try {

src/main/java/com/skycrate/backend/skycrateBackend/models/User.java

@@ -1,4 +1,4 @@
-package  com.skycrate.backend.skycrateBackend.models;
+package com.skycrate.backend.skycrateBackend.models;
 
 import java.time.LocalDateTime;
 import java.util.Collection;
@@ -6,7 +6,6 @@ import java.util.Date;
 import java.util.List;
 
 import org.hibernate.annotations.CreationTimestamp;
-import org.hibernate.annotations.UpdateTimestamp;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.userdetails.UserDetails;
 
@@ -15,7 +14,7 @@ import jakarta.persistence.*;
 @Table(name = "users")
 @Entity
 public class User implements UserDetails {
-    
+
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     @Column(nullable = false)
@@ -24,49 +23,38 @@ public class User implements UserDetails {
     @Column(nullable = false)
     private String username;
 
-    /*
-    
-   //Optional feature might add later
-
-    @Column(name = "verification_code")
-    private String verificationCode;
-
-    @Column(name ="verification_expiry")
-    private LocalDateTime verificationExpiry;
-
-    */
-
     @Column(unique = true, nullable = false)
     private String email;
 
     @Column(nullable = false)
     private String password;
 
-    
+    // ✅ Add RSA key fields
-    
+    @Lob
-    public User(){
+    @Column(name = "public_key", columnDefinition = "BLOB")
-    }
+    private byte[] publicKey;
 
-    public User(String firstname,String lastname,String email,String password){
+    @Lob
-        this.username=firstname+lastname;
+    @Column(name = "private_key", columnDefinition = "BLOB")
-        this.email=email;
+    private byte[] privateKey;
-        this.password=password;
-    }
 
 
     @CreationTimestamp
     @Column(updatable = false, name = "created_at")
     private Date createdAt;
 
-    
+    public User() {}
 
-    @Override
+    public User(String firstname, String lastname, String email, String password) {
-    public Collection<? extends GrantedAuthority> getAuthorities(){
+        this.username = firstname + lastname;
-        return List.of();
+        this.email = email;
+        this.password = password;
     }
 
-    public String getPassword() {
+    // ⬇️ Required by Spring Security
-        return password;
+    @Override
+    public Collection<? extends GrantedAuthority> getAuthorities() {
+        return List.of();
     }
 
     @Override
@@ -74,6 +62,11 @@ public class User implements UserDetails {
         return email;
     }
 
+    @Override
+    public String getPassword() {
+        return password;
+    }
+
     @Override
     public boolean isAccountNonExpired() {
         return true;
@@ -93,6 +86,8 @@ public class User implements UserDetails {
     public boolean isEnabled() {
         return true;
     }
+
+    // ⬇️ Getters and Setters
     public Integer getId() {
         return id;
     }
@@ -101,13 +96,11 @@ public class User implements UserDetails {
         this.id = id;
     }
 
-    
+    public void setFullname(String firstname, String lastname) {
-
+        this.username = firstname + lastname;
-    public void setFullname(String firstname,String lastname) {
-        this.username=firstname+lastname;
     }
 
-    public String getFullname(String firstname,String lastname){
+    public String getFullname() {
         return this.username;
     }
 
@@ -126,4 +119,21 @@ public class User implements UserDetails {
     public void setCreatedAt(Date createdAt) {
         this.createdAt = createdAt;
     }
+
+    // ✅ Getters and setters for RSA keys
+    public byte[] getPublicKey() {
+        return publicKey;
+    }
+
+    public void setPublicKey(byte[] publicKey) {
+        this.publicKey = publicKey;
+    }
+
+    public byte[] getPrivateKey() {
+        return privateKey;
+    }
+
+    public void setPrivateKey(byte[] privateKey) {
+        this.privateKey = privateKey;
+    }
 }

src/main/java/com/skycrate/backend/skycrateBackend/repository/UserRepository.java

@@ -5,6 +5,8 @@ import org.springframework.data.repository.CrudRepository;
 import com.skycrate.backend.skycrateBackend.models.User;
 public interface UserRepository extends CrudRepository<User,Integer> {
     Optional<User> findByEmail(String email);
+    // Custom query method to find user by username
+    Optional<User> findByUsername(String username);
     /*
     // might use later
      Optional<User> findByVerificationCode(String verificationCode);

src/main/java/com/skycrate/backend/skycrateBackend/services/AuthenticationService.java

@@ -9,37 +9,49 @@ import com.skycrate.backend.skycrateBackend.dto.LoginUserDto;
 import com.skycrate.backend.skycrateBackend.dto.RegisterUserDto;
 import com.skycrate.backend.skycrateBackend.models.User;
 import com.skycrate.backend.skycrateBackend.repository.UserRepository;
+import com.skycrate.backend.skycrateBackend.utils.RSAKeyUtil;
+
+import java.security.KeyPair;
+import java.security.NoSuchAlgorithmException;
 
 @Service
 public class AuthenticationService {
-    
+
     private final UserRepository userRepository;
     private final PasswordEncoder passwordEncoder;
     private final AuthenticationManager authenticationManager;
 
-    public AuthenticationService( UserRepository userRepository, AuthenticationManager authenticationManager , PasswordEncoder passwordEncoder){
+    public AuthenticationService(UserRepository userRepository, AuthenticationManager authenticationManager, PasswordEncoder passwordEncoder) {
-        this.userRepository=userRepository;
+        this.userRepository = userRepository;
-        this.passwordEncoder=passwordEncoder;
+        this.passwordEncoder = passwordEncoder;
-        this.authenticationManager=authenticationManager;
+        this.authenticationManager = authenticationManager;
     }
 
-    public User signUp(RegisterUserDto inputuser){
+    public User signUp(RegisterUserDto inputUser) {
-        User user=new User(inputuser.getFirstname(),inputuser.getLastname(),inputuser.getEmail(),passwordEncoder.encode(inputuser.getPassword()));
+        User user = new User(
-        /*
+                inputUser.getFirstname(),
-        User user = new User()
+                inputUser.getLastname(),
-        .setFullname(inputuser.getFirstname(),inputuser.getLastname())
+                inputUser.getEmail(),
-        .setEmail(inputuser.getEmail())
+                passwordEncoder.encode(inputUser.getPassword())
-        .setPassword(passwordEncoder.encode(inputuser.getPassword()));
+        );
-        */
 
-        return userRepository.save(user) ;
+        try {
+            KeyPair keyPair = RSAKeyUtil.generateKeyPair();
+            user.setPublicKey(keyPair.getPublic().getEncoded());
+            user.setPrivateKey(keyPair.getPrivate().getEncoded());
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException("Failed to generate RSA key pair", e);
+        }
+
+        return userRepository.save(user);
     }
 
-    public User authenticate(LoginUserDto inputuser){
+    public User authenticate(LoginUserDto inputUser) {
-        authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(inputuser.getEmail()
+        authenticationManager.authenticate(
-                                            , inputuser.getPassword()));
+                new UsernamePasswordAuthenticationToken(inputUser.getEmail(), inputUser.getPassword())
-        return userRepository.findByEmail(inputuser.getEmail()).orElseThrow();
+        );
 
+        return userRepository.findByEmail(inputUser.getEmail())
+                .orElseThrow(() -> new RuntimeException("User not found"));
     }
-
+}
-}

src/main/java/com/skycrate/backend/skycrateBackend/services/EncryptionUtil.java

@@ -23,13 +23,13 @@ public class EncryptionUtil {
         // Step 1: Generate AES Key
         SecretKey aesKey = generateAESKey();
 
-        // Step 2: Encrypt data using AES
+        // Encrypt data using AES
-        Cipher aesCipher = Cipher.getInstance(AES_ALGORITHM);
+        Cipher aesCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
         aesCipher.init(Cipher.ENCRYPT_MODE, aesKey);
         byte[] encryptedData = aesCipher.doFinal(data);
 
-        // Step 3: Encrypt the AES key with RSA
+        // Encrypt the AES key with RSA
-        Cipher rsaCipher = Cipher.getInstance(RSA_ALGORITHM);
+        Cipher rsaCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
         rsaCipher.init(Cipher.ENCRYPT_MODE, publicKey);
         byte[] encryptedAesKey = rsaCipher.doFinal(aesKey.getEncoded());
 
@@ -65,13 +65,15 @@ public class EncryptionUtil {
         System.arraycopy(encryptedCombined, 4 + aesKeyLength, encryptedData, 0, encryptedData.length);
 
         // Step 3: Decrypt the AES key using RSA
-        Cipher rsaCipher = Cipher.getInstance(RSA_ALGORITHM);
+        Cipher rsaCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
         rsaCipher.init(Cipher.DECRYPT_MODE, privateKey);
         byte[] aesKeyBytes = rsaCipher.doFinal(encryptedAesKey);
-        SecretKey aesKey = new SecretKeySpec(aesKeyBytes, AES_ALGORITHM);
 
-        // Step 4: Decrypt the data using AES
+        // Create AES key
-        Cipher aesCipher = Cipher.getInstance(AES_ALGORITHM);
+        SecretKey aesKey = new SecretKeySpec(aesKeyBytes, "AES");
+
+        // Decrypt the data using AES
+        Cipher aesCipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
         aesCipher.init(Cipher.DECRYPT_MODE, aesKey);
         return aesCipher.doFinal(encryptedData);
     }

src/main/java/com/skycrate/backend/skycrateBackend/services/HDFSOperations.java

@@ -1,10 +1,15 @@
 package com.skycrate.backend.skycrateBackend.services;
 
 import com.skycrate.backend.skycrateBackend.config.HDFSConfig;
-import com.skycrate.backend.skycrateBackend.utils.KeyUtil;
+import com.skycrate.backend.skycrateBackend.models.User;
+import com.skycrate.backend.skycrateBackend.repository.UserRepository;
+import com.skycrate.backend.skycrateBackend.utils.RSAKeyUtil;
+import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.io.IOUtils;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
 import javax.crypto.Cipher;
@@ -12,6 +17,8 @@ import javax.crypto.KeyGenerator;
 import javax.crypto.SecretKey;
 import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.SecretKeySpec;
+import java.io.ByteArrayInputStream;
+import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Paths;
@@ -25,49 +32,91 @@ import java.util.List;
 
 @Service
 public class HDFSOperations {
+    private final UserRepository userRepository;
 
-    public void uploadFile(String localPath, String hdfsPath, String uploadedFileName, String username) {
+    @Autowired
+    public HDFSOperations(UserRepository userRepository) {
+        this.userRepository = userRepository;
+    }
+
+    public void uploadFile(byte[] fileData, String hdfsPath, String uploadedFileName, String username) {
         try {
             FileSystem fs = HDFSConfig.getHDFS();
-            byte[] data = Files.readAllBytes(Paths.get(localPath)); // Read file as bytes
 
-            // Encrypt file (consider adding encryption here as needed)
+            // Create an InputStream from the byte array
-            byte[] encryptedData = data;
+            ByteArrayInputStream inputStream = new ByteArrayInputStream(fileData);
-
-            String tempFilePath = localPath + ".enc";
-            Files.write(Paths.get(tempFilePath), encryptedData);
 
+            // Prepare the path for HDFS
             String finalHdfsPath = hdfsPath.endsWith("/") ? hdfsPath + uploadedFileName : hdfsPath + "/" + uploadedFileName;
-            fs.copyFromLocalFile(new Path(tempFilePath), new Path(finalHdfsPath));
 
-            Files.delete(Paths.get(tempFilePath));
+            // Upload the file directly to HDFS from the InputStream
+            Path hdfsFilePath = new Path(finalHdfsPath);
+            FSDataOutputStream outputStream = fs.create(hdfsFilePath);
+            IOUtils.copyBytes(inputStream, outputStream, 4096, true);
+
         } catch (IOException e) {
             // Handle I/O exception and log the error
-            throw new RuntimeException("Failed to upload file due to I/O issue: " + e.getMessage(), e);
+            throw new RuntimeException("Failed to upload file to HDFS: " + e.getMessage(), e);
         } catch (Exception e) {
             // Catch any other exceptions
-            throw new RuntimeException("Failed to upload file: " + e.getMessage(), e);
+            throw new RuntimeException("Failed to upload file to HDFS: " + e.getMessage(), e);
         }
     }
 
-    public void downloadFile(String hdfsPath, String localPath, String username) {
+    public void downloadFile(String hdfsEncPath, String localPathWithoutExt, String username) {
         try {
             FileSystem fs = HDFSConfig.getHDFS();
-            String tempFilePath = localPath + ".enc";
 
-            fs.copyToLocalFile(new Path(hdfsPath), new Path(tempFilePath));
+            // Extract file name and extension
+            String encFileName = new File(hdfsEncPath).getName();
+            String originalFileName = encFileName.replace(".enc", "");
+            String fileExtension = originalFileName.substring(originalFileName.lastIndexOf(".") + 1);
 
-            byte[] encryptedData = Files.readAllBytes(Paths.get(tempFilePath));
+            String fullDecryptedPath = localPathWithoutExt + "/" + originalFileName;
-            byte[] decryptedData = encryptedData; // Decrypt if needed
+            String encFilePath = fullDecryptedPath + ".enc";
+            String keyFilePath = fullDecryptedPath + ".key";
+
+            // Download encrypted file and AES key from HDFS
+            fs.copyToLocalFile(new Path(hdfsEncPath), new Path(encFilePath));
+            fs.copyToLocalFile(new Path(hdfsEncPath.replace(".enc", ".key")), new Path(keyFilePath));
+
+            // Read the encrypted AES key
+            byte[] encryptedAesKey = Files.readAllBytes(Paths.get(keyFilePath));
+            System.out.println("Length of encrypted AES key: " + encryptedAesKey.length);
+
+            // Retrieve the RSA private key for the user
+            User user = userRepository.findByUsername(username)
+                    .orElseThrow(() -> new RuntimeException("User not found"));
+            PrivateKey privateKey = RSAKeyUtil.getPrivateKeyFromBytes(user.getPrivateKey());
+
+            Cipher rsaCipher = Cipher.getInstance("RSA");
+            rsaCipher.init(Cipher.DECRYPT_MODE, privateKey);
+            byte[] aesKeyBytes = rsaCipher.doFinal(encryptedAesKey);
+
+            // Ensure valid AES key length
+            if (aesKeyBytes.length != 16 && aesKeyBytes.length != 24 && aesKeyBytes.length != 32) {
+                throw new RuntimeException("Invalid AES key length: " + aesKeyBytes.length + " bytes");
+            }
+
+            SecretKey aesKey = new SecretKeySpec(aesKeyBytes, 0, aesKeyBytes.length, "AES");
+
+            // Read the encrypted file content
+            byte[] encryptedFileContent = Files.readAllBytes(Paths.get(encFilePath));
+
+            // Decrypt the file content using AES
+            Cipher aesCipher = Cipher.getInstance("AES/ECB/PKCS5Padding"); // Specify padding
+            aesCipher.init(Cipher.DECRYPT_MODE, aesKey);
+            byte[] decryptedFileContent = aesCipher.doFinal(encryptedFileContent);
+
+            // Write the decrypted content to the original file
+            Files.write(Paths.get(fullDecryptedPath + "." + fileExtension), decryptedFileContent);
+
+            // Cleanup temporary files
+            Files.deleteIfExists(Paths.get(encFilePath));
+            Files.deleteIfExists(Paths.get(keyFilePath));
 
-            Files.write(Paths.get(localPath), decryptedData);
-            Files.delete(Paths.get(tempFilePath));
-        } catch (IOException e) {
-            // Handle I/O exception and log the error
-            throw new RuntimeException("Failed to download file due to I/O issue: " + e.getMessage(), e);
         } catch (Exception e) {
-            // Catch any other exceptions
+            throw new RuntimeException("Failed to download or decrypt file: " + e.getMessage(), e);
-            throw new RuntimeException("Failed to download file: " + e.getMessage(), e);
         }
     }
 

src/main/java/com/skycrate/backend/skycrateBackend/utils/KeyUtil.java

@@ -3,24 +3,37 @@ package com.skycrate.backend.skycrateBackend.utils;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.security.KeyFactory;
+import java.security.*;
-import java.security.PrivateKey;
-import java.security.PublicKey;
 import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.X509EncodedKeySpec;
 
 public class KeyUtil {
-    public static PrivateKey getPrivateKeyForUser(String username) throws Exception {
+
-        Path path = Paths.get("keys", username + "_private.key");
+    public static void generateAndStoreKeyPair(String username) throws Exception {
-        byte[] bytes = Files.readAllBytes(path);
+        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
-        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(bytes);
+        keyPairGenerator.initialize(2048); // Key size
-        return KeyFactory.getInstance("RSA").generatePrivate(keySpec);
+        KeyPair keyPair = keyPairGenerator.generateKeyPair();
+
+        // Store the public key
+        Path publicKeyPath = Paths.get("C:\\Users\\sonal\\OneDrive\\Desktop\\SkyCrate\\Skycrate\\keys", username + "_public.key");
+        Files.write(publicKeyPath, keyPair.getPublic().getEncoded());
+
+        // Store the private key
+        Path privateKeyPath = Paths.get("C:\\Users\\sonal\\OneDrive\\Desktop\\SkyCrate\\Skycrate\\keys", username + "_private.key");
+        Files.write(privateKeyPath, keyPair.getPrivate().getEncoded());
     }
 
     public static PublicKey getPublicKeyForUser(String username) throws Exception {
-        Path path = Paths.get("keys", username + "_public.key");
+        Path path = Paths.get("C:\\Users\\sonal\\OneDrive\\Desktop\\SkyCrate\\Skycrate\\keys", username + "_public.key");
         byte[] bytes = Files.readAllBytes(path);
         X509EncodedKeySpec keySpec = new X509EncodedKeySpec(bytes);
         return KeyFactory.getInstance("RSA").generatePublic(keySpec);
     }
+
+    public static PrivateKey getPrivateKeyForUser(String username) throws Exception {
+        Path path = Paths.get("C:\\Users\\sonal\\OneDrive\\Desktop\\SkyCrate\\Skycrate\\keys", username + "_private.key");
+        byte[] bytes = Files.readAllBytes(path);
+        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(bytes);
+        return KeyFactory.getInstance("RSA").generatePrivate(keySpec);
+    }
 }

src/main/java/com/skycrate/backend/skycrateBackend/utils/RSAKeyUtil.java

@@ -0,0 +1,70 @@
+package com.skycrate.backend.skycrateBackend.utils;
+
+import javax.crypto.*;
+import java.security.*;
+import java.security.spec.PKCS8EncodedKeySpec;
+import java.security.spec.X509EncodedKeySpec;
+import javax.crypto.spec.SecretKeySpec;
+
+public class RSAKeyUtil {
+
+    // Generate RSA Key Pair
+    public static KeyPair generateKeyPair() throws NoSuchAlgorithmException {
+        KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
+        generator.initialize(2048); // Key size
+        return generator.generateKeyPair();
+    }
+
+    // Convert byte array to PublicKey
+    public static PublicKey getPublicKeyFromBytes(byte[] publicKeyBytes) throws Exception {
+        X509EncodedKeySpec spec = new X509EncodedKeySpec(publicKeyBytes);
+        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
+        return keyFactory.generatePublic(spec);
+    }
+
+    // Convert byte array to PrivateKey
+    public static PrivateKey getPrivateKeyFromBytes(byte[] privateKeyBytes) throws Exception {
+        PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(privateKeyBytes);
+        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
+        return keyFactory.generatePrivate(spec);
+    }
+
+    // Encrypt data using RSA (with padding)
+    public static byte[] encrypt(byte[] data, PublicKey publicKey) throws Exception {
+        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding"); // Specify padding
+        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
+        return cipher.doFinal(data);
+    }
+
+    // Decrypt data using RSA (with padding)
+    public static byte[] decrypt(byte[] encryptedData, PrivateKey privateKey) throws Exception {
+        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding"); // Specify padding
+        cipher.init(Cipher.DECRYPT_MODE, privateKey);
+        return cipher.doFinal(encryptedData);
+    }
+
+    // Generate AES Key (128, 192, or 256 bits)
+    public static SecretKey generateAESKey(int keySize) throws NoSuchAlgorithmException {
+        if (keySize != 128 && keySize != 192 && keySize != 256) {
+            throw new IllegalArgumentException("Invalid AES key size. Must be 128, 192, or 256 bits.");
+        }
+        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
+        keyGenerator.init(keySize); // Specify the key size
+        return keyGenerator.generateKey();
+    }
+
+    // Encrypt AES Key using RSA
+    public static byte[] encryptAESKey(SecretKey aesKey, PublicKey publicKey) throws Exception {
+        return encrypt(aesKey.getEncoded(), publicKey); // Encrypt the AES key using RSA
+    }
+
+    // Decrypt AES Key using RSA
+    public static SecretKey decryptAESKey(byte[] encryptedAESKey, PrivateKey privateKey, int keySize) throws Exception {
+        byte[] decryptedKey = decrypt(encryptedAESKey, privateKey); // Decrypt with RSA
+        // Ensure that the decrypted key length matches the expected AES key size
+        if (decryptedKey.length != keySize / 8) {
+            throw new IllegalArgumentException("Decrypted key size does not match expected AES key size.");
+        }
+        return new SecretKeySpec(decryptedKey, 0, decryptedKey.length, "AES"); // Convert to AES Key
+    }
+}

src/main/resources/application.properties

@@ -3,6 +3,8 @@ spring.application.name=skycrateBackend
 spring.servlet.multipart.max-file-size=1000MB
 spring.servlet.multipart.max-request-size=1000MB
 
+spring.servlet.multipart.enabled=true
+
 security.jwt.secret-key=3cfa76ef14937c1c0ea519f8fc057a80fcd04a7420f8e8bcd0a7567c272e007b
 security.jwt.expiration-time=3600000
 
@@ -17,7 +19,7 @@ spring.jpa.properties.hibernate.format_sql=true
 spring.jpa.open-in-view=false
 logging.level.org.springframework.security.config.annotation.authentication.configuration.InitializeUserDetailsBeanManagerConfigurer=ERROR
 
-server.port=8081
+server.port=8080
 
 
 

src/test/java/com/skycrate/backend/skycrateBackend/SkycrateBackendApplicationTests.java

@@ -1,13 +0,0 @@
-package com.skycrate.backend.skycrateBackend;
-
-import org.junit.jupiter.api.Test;
-import org.springframework.boot.test.context.SpringBootTest;
-
-@SpringBootTest
-class SkycrateBackendApplicationTests {
-
-	@Test
-	void contextLoads() {
-	}
-
-}

tmp/Hello.txt

@@ -1 +0,0 @@
-Hello World!!!