Dropbear (software)

Dropbear
DeveloperMatt Johnston
ReleaseApril 2003, 06; 23 years ago (06-04-2003)
Stable release
2026.90 Edit this on Wikidata / 3 May 2026
Written inC
Operating systemUnix-like
TypeRemote access
LicenseMIT license
Websitematt.ucc.asn.au/dropbear/dropbear.html
Repository

Dropbear is a software package written by Matt Johnston that provides a Secure Shell-compatible server and client. It is designed as a replacement for standard OpenSSH for environments with low memory and processor resources, such as embedded systems. It is a core component of OpenWrt and other router distributions.

Dropbear was originally released in April 2003.

Technology

Dropbear implements version 2 of the Secure Shell (SSH) protocol.

The cryptographic algorithms are implemented using third-party cryptographic libraries like LibTomCrypt included internally in the Dropbear distribution. It derives some parts from OpenSSH to handle BSD-style pseudo terminals.

Features

Dropbear implements the complete SSH version 2 protocol in both the client and the server. It does not support SSH version 1 backwards-compatibility in order to save space and resources, and to avoid the inherent security vulnerabilities in SSH version 1. SCP is also implemented. SFTP support relies on a binary file which can be provided by OpenSSH or similar programs.[citation needed] FISH works in any case and is supported by Konqueror.

Dropbear supports elliptic curve cryptography for key exchange, as of version 2013.61test and beyond.

See also

References

  1. ↑ "Dropbear SSH".
  2. ↑ "VA Technical Reference Model v 24.4. Dropbear Secure Shell (SSH) Server". oit.va.gov. 2019-09-04. Archived from the original on 2024-06-15. Retrieved 2024-06-27.
  3. ↑ "dropbear(8)". Ubuntu. Archived from the original on 2021-12-01. Retrieved 2020-05-23.
  4. ↑ Matt Johnston. "Dropbear SSH". Archived from the original on 2018-03-30. Retrieved 2020-05-23. PTY handling code is taken from OpenSSH
  5. ↑ Liu, Dale (2011-04-18). Next Generation SSH2 Implementation: Securing Data in Motion. Syngress. ISBN 978-0-08-057000-6.
  6. ↑ Aufranc, Jean-Luc (October 6, 2011). "Dropbear: Lightweight SSH Server". CodingHW. Archived from the original on 2024-06-27. Retrieved 2024-06-27.
  7. ↑ Matt Johnston (2004-06-01). "Makefile.in contains updated files required". Retrieved 2020-05-23.[permanent dead link]
  8. ↑ "CHANGES". 14 November 2013. Archived from the original on 2018-03-23. Retrieved 2020-05-23. ECC (elliptic curve) support. Supports ECDSA hostkeys (requires new keys to be generated) and ECDH for setting up encryption keys[...]