Dropbear (software) explained

Dropbear
Developer:Matt Johnston
Programming Language:C
Operating System:Unix-like
Genre:Remote access
License:MIT license

Dropbear is a software package written by Matt Johnston that provides a Secure Shell-compatible server and client.[1] 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.[2]

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.[3]

Features

Dropbear implements the complete SSH version 2 protocol in both the client and the server.[4] [5] 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.[6] SFTP support relies on a binary file which can be provided by OpenSSH or similar programs. 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.[7]

See also

Notes and References

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