- SSH (Secure Shell) software
- Cryptographic random number generation
- SHA-1 message digest generator
- Other SSH clients
- Mailing lists
## SSH (Secure Shell) software
Please note that newer versions of psftp, pscp and plink may now be found in the Unix Porting Project (archive 'putty' in directory 'terminal These left here are merely for historical interest

Current versions are:
- puttytools (psftp, pscp, plink) Snapshot 2004-01-31 (download binaries, sources). Version history

- SSHProxy 0.20 (download binaries, sources). Version history. CVSWeb

- Historical pscp 0.49b-07:
Please use pscp in puttytools above instead. (download binaries, sources). Version history CVSWeb

puttytools, SSHProxy and pscp are clients for the SSH protocol, which allows secure connections between computers over networks that may be eavesdropped by others or subject to security attacks by third parties. puttytools support the SSH protocol version 2, whilst SSHProxy and historical pscp only support version 1. They are based on the Windows SSH client PuTTY. To run they need CryptRandom (see below) to be installed

SSHProxy provides SSH terminal sessions, whilst psftp and pscp perform file transfer. plink does X11 and port forwarding, and allows the running of programs on the remote computer (similar to rsh)

Why might you want to use SSH instead of telnet, FTP, rlogin or rcp? There are plenty of guides on the web - one example is from Berkeley
I have also compiled a 32 bit compatible version of NettleSSH, by Justin Fletcher and the Nettle developers, which is an SSH v1 client integrated into the Nettle terminal emulator/telnet client, with rlogin and rexec support added too. This is an unofficial release, and since I haven't made any changes to the code it retains the same version number of 0.2023 but with “32-bit” appended. Any bugs in this version are probably mine, so please don't ask Justin to support it. Source is included

## CryptRandom
Current version is 0.13 (download binaries v0.13 in RiscPkg format; v0.12 with documentation are also available), sources for v0.13 in CVSWeb, or v0.12). This is RISC OS 5 and ARMv7 compatible. Version history. CVSWeb

*Security advisory for CryptRandom versions 0.05 to 0.08 inclusive (dated 3 November 2002
CryptRandom is a module for generating cryptographically useful random bytes under RISC OS

 Why?
Computers are, by their nature, deterministic - so applying the same
sequence

of inputs to any program is likely to produce the same result. This is a
**bad thing** when it comes to cryptography, as if you use a known sequence to
encrypt a data stream, next time you turn on your machine you'll use the
same
known sequence, making the code possible to break. Thus we need a random
sequence so that no pattern can be spotted in it. Basic provides a
pseudo-random sequence, but this is the same every time the machine is
turned
on, so is not very good. It is also just a sequence, which will eventually
repeat. True randomness is only possible on a computer by attaching it to
other devices such as a radioactive source - not very practical

CryptRandom
applies another method, which will produce different values showing to no
known pattern, which are different each time you switch the machine on

This is much less secure than using a true random source, but better than
using a predictable random number generator like that Basic uses. See the
readme file for more details on how it works

## SHA1 module
Current version is 0.03 (download binaries, sources - same source archive as CryptRandom above). This is RISC OS 5 compatible. Version history. CVSWeb

SHA1 is a module for generating a SHA-1 message digest under RISC OS

# Other SSH softwareFor completeness, links are included here to SSH software produced by other developers. You might find some of this software better than
- NettleSSH. An SSH client (based on the SSHProxy code) built into popular telnet client Nettle. See above for my 32 bit compatible build

- PuTTY command line port by Alex Macfarlane Smith, based on a later PuTTY codebase than SSHProxy. Support SSH 2

- OpenSSH port from Peter Naulls' Unix Porting Project

Page by Theo Markettos (email at theo [at@] markettos.org.uk), last modified 2012-06-01
Return to Theo's RISC OS pages.