---
name: "kup-server"
section: "1"
platform: "linux"
package: "kup-server"
version: "0.3.6-4"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/kup-server"
---

# kup-server(1)

kernel.org upload server utility

## NAME

kup-server - kernel.org upload server utility

## DESCRIPTION

The program **kup-server** is expected to be the receiver of an ssh shell, configured with the following or similar options in ~/.ssh/authorized\_keys:

command="/usr/bin/kup-server",no-agent-forwarding,no-port-forwarding,no-pty,no-user-rc,no-X11-forwarding ssh-rsa AAAA\[...\]

Each user should have their own UID, as Unix user permissions are used for specific tree access control. On the client side, a corresponding client-side utility **kup** is used to initiate the connection and perform the uploads.

## GLOBAL CONFIG

The configuration file for  **kup-server** is located in /etc/kup/kup-server.cfg and has the following options:

- **\[paths\]**

  All paths in this section should be disjoint. Do not combine any of them into one directory.

- **data\_path** = */var/lib/kup/pub*

  Path for public consumption, e.g. served via http or rsync.

- **git\_path** = */var/cache/git*

  This is the path where git trees (for the TAR and DIFF options) are available.  Those should be readonly for the uploaders.

- **lock\_file** = */run/kup/lock*

  A common lock file for data\_path.  No program should modify the content in data\_path without holding an flock on this file.  Should be readonly for the uploaders.

- **tmp\_path** = */var/cache/kup/tmp/*

  tmp\_path can be either:

1\. a directory writable by every user and with the sticky bit set (typically mode 1777 or 1770).  In that case, DO NOT end the path with a slash, or:

2\. A directory containing an empty directory for each user (named for that user), owned by that user and mode 0700. In this case, DO end the path with a slash.

In either case, this directory tree  **MUST** be on the same filesystem as **data\_path**, since the script expects tocreate files in this directory and rename() them into data\_path.

- **pgp\_path** = */var/lib/kup/pgp*

  A directory containing a GnuPG public keyring for each user, named \<user\>.gpg and readable (but not writable) by that user.

- **\[limits\]**

  All sizes are in bytes, all times in seconds.

- **max\_data** = *8589934592*

  Max size of uploaded data.

- **bufsiz** = *262144*

  Buffer size when reading data.

- **timeout\_command** = *30*

  How long to wait for a command to time out.

- **timeout\_data** = *300*

  Must read at least bufsiz bytes in this timespan.

- **timeout\_compress** = *900*

  Uncompressing tarballs must take at most this long.

- **timeout\_compress\_cpu** = *900*

  Each compression command must take at most this long in CPU time.

- **\[compressors\]**

  This section allows specifying the compressors to use when creating compressed versions of uploaded content.

- **use** = *gz, xz*

  A comma-separated list of file extensions to create (minus the leading dot). For each extension specified, you will need to add a matching section specifying which command and flags to use for decompression and which for compression. Make sure to configure the decompress command to output to stdout. E.g.:

```
[gz]
compress_command = /bin/pigz -9
decompress_command = /bin/gzip -cd
[xz]
compress_command = /bin/xz -9 -T0
decompress_command = /bin/xz -cd
```

## AUTHOR

Written by H. Peter Anvin \<hpa@zytor.com\>.

## COPYRIGHT

Copyright © 2011 Intel Corporation

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, Inc.; either version 2 of the License, or (at your option) any later version; incorporated herein by reference.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

## SEE ALSO

[**kup**(1)](/kup/1.md)