From 3975f8b0440db12f89cfe607d909bb9bd7a1ad5c Mon Sep 17 00:00:00 2001
From: Ahmed Harhash <email@lacentix.me>
Date: Tue, 16 Apr 2024 08:53:31 +0200
Subject: [PATCH] easy-installer: Implement Direct Post-Download Integrity
 Check in DownloadTask

---
 .../easy/installer/tasks/DownloadTask.java    | 58 ++++++++++---------
 1 file changed, 31 insertions(+), 27 deletions(-)

diff --git a/src/main/java/ecorp/easy/installer/tasks/DownloadTask.java b/src/main/java/ecorp/easy/installer/tasks/DownloadTask.java
index 2d23b134..5e26d1eb 100644
--- a/src/main/java/ecorp/easy/installer/tasks/DownloadTask.java
+++ b/src/main/java/ecorp/easy/installer/tasks/DownloadTask.java
@@ -32,6 +32,9 @@ import java.net.MalformedURLException;
 import java.net.URL;
 import java.nio.channels.Channels;
 import java.nio.channels.ReadableByteChannel;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.text.DecimalFormat;
@@ -103,50 +106,51 @@ public class DownloadTask extends Task<Boolean>{
         final String localFilePath = AppConstants.getSourcesFolderPath() + fileName;
 
         final String checksumFilePath = localFilePath + checkSumExtension;
-        
-        if(isCancelled()) return false;
-        
+
+        if (isCancelled()) return false;
+
         this.updateTitle("Downloading " + latestBuildFilename + checkSumExtension);
-        
-        
-        File checksumLmdFile = new File(AppConstants.getSourcesFolderPath()+"lmd."+fileName+checkSumExtension);
+
+        File checksumLmdFile = new File(AppConstants.getSourcesFolderPath() + "lmd." + fileName + checkSumExtension);
         checksumLmdFile.createNewFile();
-        
-        // Download checksum. If file not downloaded return false and stop downloadin because integrity isn't guaranteed
-        if( !downloadFile(targetUrl+checkSumExtension, checksumFilePath,checksumLmdFile) ){
+
+        if (!downloadFile(targetUrl + checkSumExtension, checksumFilePath, checksumLmdFile)) {
             updateMessage(i18n.getString("download_lbl_cantcheckIntegrity"));
             return false;
         }
 
-        //If checksum valid it means that file is already there and up to date
-        updateMessage(i18n.getString("download_lbl_checkingIntegrity")); 
-        if ( validChecksum(checksumFilePath) ){
+        updateMessage(i18n.getString("download_lbl_checkingIntegrity"));
+        if (validChecksum(checksumFilePath)) {
             updateMessage(i18n.getString("download_lbl_fileAlreadyUptoDate"));
             return true;
         }
 
-        if(isCancelled()) return false;
+        if (isCancelled()) return false;
 
-        this.updateTitle("Downloading "+ latestBuildFilename);
+        this.updateTitle("Downloading " + latestBuildFilename);
 
-        final String tmpFilePath = AppConstants.getSourcesFolderPath()+"tmp."+fileName;
-        
-        File lmdFile = new File(AppConstants.getSourcesFolderPath()+"lmd."+fileName); //used to Store last modified Date of remote content
+        final String tmpFilePath = localFilePath;
+
+        File lmdFile = new File(AppConstants.getSourcesFolderPath() + "lmd." + fileName);
         lmdFile.createNewFile();
-        
-        if ( downloadFile(targetUrl, tmpFilePath, lmdFile) )//Download file
-        {
-            logger.debug("Downloaded succeed. Rename temp file to right fileName");
-            File tmpFile = new File(tmpFilePath);
-            tmpFile.renameTo(new File(localFilePath));
-            return validChecksum(checksumFilePath);
-
-        }else{
+
+        if (downloadFile(targetUrl, tmpFilePath, lmdFile)) {
+            logger.debug("Download succeeded. Performing checksum validation.");
+
+            if (validChecksum(checksumFilePath)) {
+                return true; // Download successful and checksum validated
+            } else {
+                updateMessage(i18n.getString("download_lbl_invalidChecksum"));
+                // Delete the downloaded file as checksum validation failed
+                Files.deleteIfExists(Paths.get(localFilePath));
+                return false;
+            }
+        } else {
             updateMessage(i18n.getString("download_lbl_downloadError"));
             return false;
         }
     }
-    
+
     // method link to file downloading
     
     /**
-- 
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