Implementation of a SSH server in C# This should cover basic functionality and encryption but not the advanced features of a full blown SSH server. The idea is to cover atleast one algorithm of each type from the list of required algorithms for a client. The client in this case being Putty supporting SSH-2.0. Based on the idea by TyrenDe.

Algorithms (to be) supported by this server -
key exchange - diffie-hellman-group14-sha1
host key algorithm - ssh-rsa
encryption - 3des-cbc
mac algorithm - hmac-sha1
compression - none

Packet Protocol (https://tools.ietf.org/html/rfc4253)

uint32 packet_length
byte padding_length
byte[n1] payload; n1 = packet_length - padding_length - 1
byte[n2] random padding; n2 = padding_length
byte[m] mac (Message Authentication Code - MAC); m = mac_length

Changelog

0.1

• Added ability to listen for incoming connections and manage connections

0.2

• Added multiple client management

0.3

• Read protocol exchange string from client

0.4

• Read key exchange packet (*broken)

0.5

• Read key exchange packet working

0.6

• Added support for cipher, mac, keyhost and encryption algorithms