FTP TLS Session Not Resumed - Unable to Upload Files to FileZilla Server
- Dominant language
- Java
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Description
### Apache NetBeans version
Apache NetBeans 22
### What happened
When using NetBeans to connect to a FileZilla FTP server via FTP over TLS (FTPS), the IDE successfully establishes the initial control connection and navigates through directories. However, when attempting to upload a file, the data connection fails with an error stating that the TLS session could not be resumed. This issue specifically arises during the transition from the control connection to the data connection, preventing any file uploads from being completed. The server responds with a 425 Unable to build data connection: TLS session of data connection not resumed error, indicating that the TLS handshake for the data connection could not be successfully resumed or established.
### Language / Project Type / NetBeans Component
PHP Application from remote server
### How to reproduce
1. Configure a FileZilla FTP Server (version 1.8.2) to use FTP over TLS (explicit mode).
2. In NetBeans (version 22), configure an FTP connection in Explicit FTP using TLS in passive mode
3. Attempt to upload a file to the server.
**Expected Behavior:**
The file should upload successfully without any issues.
**Actual Behavior:**
The upload fails with the following error message:
`425 Unable to build data connection: TLS session of data connection not resumed.`
The server log shows the following error:
`GnuTLS error -110: The TLS connection was non-properly terminated.`
**Environment:**
```
Product Version: Apache NetBeans IDE 22
Java: 22.0.2; Java HotSpot(TM) 64-Bit Server VM 22.0.2+9-70
Runtime: Java(TM) SE Runtime Environment 22.0.2+9-70
System: Mac OS X version 14.6.1 running on aarch64; UTF-8; fr_BE (nb)
```
**Additional Information:**
- The issue does not occur when using other FTP clients like FileZilla Client.
- I have tried various configurations in both NetBeans and FileZilla Server, including different TLS versions and passive/active modes, but the problem persists.
- It seems that NetBeans is unable to resume the TLS session for the data connection after the control connection is established.
- No problem when I use Pure FTP (FTP without encryption with TLS)
- FileZilla Server is in last version (1.8.2) and use TLS 1.2 minimum
**Suggestions for Resolution:**
- Investigate the handling of TLS sessions in NetBeans, especially in how it resumes or establishes a new TLS session for data connections.
- Provide an option in NetBeans to disable the requirement for TLS session resumption, if possible.
### Did this work correctly in an earlier version?
Apache NetBeans 22
### Operating System
Mac OS Sonoma (version 14.6.1)
### JDK
Java: 22.0.2; Java HotSpot(TM) 64-Bit Server VM 22.0.2+9-70 / Runtime: Java(TM) SE Runtime Environment 22.0.2+9-70
### Apache NetBeans packaging
Apache NetBeans provided installer
### Anything else
_No response_
### Are you willing to submit a pull request?
No
Contributor guide
Research direction
Reproduce the failure with FileZilla Server 1.8.2 using explicit FTPS in passive mode, then trace NetBeans handling of the TLS data connection after the control connection is established. Done means uploading a file succeeds without the “TLS session of data connection not resumed” error.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- java, php
- Domain
- tooling
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Needs clarification
- Newbie friendliness
- 35/100