Dropbear is a software package written by Matt Johnston that provides a

Secure Shell The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command-line execution. SSH applications are based on a ...

-compatible server and client. It is designed as a replacement for standard

OpenSSH OpenSSH (also known as OpenBSD Secure Shell) is a suite of secure networking utilities based on the Secure Shell (SSH) protocol, which provides a secure channel over an unsecured network in a client–server architecture. Network Working Gr ...

for environments with low memory and processor resources, such as

embedded systems An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' as ...

. It is a core component of

OpenWrt OpenWrt (from ''open wireless router'') is an open-source project for embedded operating systems based on Linux, primarily used on embedded devices to route network traffic. The main components are Linux, util-linux, musl, and BusyBox. All com ...

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 The Berkeley Software Distribution or Berkeley Standard Distribution (BSD) is a discontinued operating system based on Research Unix, developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berk ...

-style

pseudo terminal In some operating systems, including Unix and Linux, a pseudoterminal, pseudotty, or PTY is a pair of pseudo-device endpoints (files) which establish asynchronous, bidirectional communication ( IPC) channel (with two ports) between two or more pr ...

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.

FISH Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

works in any case and is supported by

Konqueror Konqueror is a free and open-source web browser and file manager that provides web access and file-viewer functionality for file systems (such as local files, files on a remote FTP server and files in a disk image). It forms a core part of ...

. Dropbear supports

elliptic curve cryptography Elliptic-curve cryptography (ECC) is an approach to public-key cryptography based on the algebraic structure of elliptic curves over finite fields. ECC allows smaller keys compared to non-EC cryptography (based on plain Galois fields) to provide e ...

for key exchange, as of version 2013.61test and beyond.

References

External links

* {{DEFAULTSORT:Dropbear (Software) Cryptographic software Free network-related software Free security software Secure Shell Software using the MIT license Free software programmed in C

Technology

Features

See also

References

External links