handy_sshd

README

handy-sshd

Portable SSH Server

Install on Ubuntu/Debian

wget https://github.com/nwtgck/handy-sshd/releases/download/v0.4.0/handy-sshd-0.4.0-linux-amd64.deb
sudo dpkg -i handy-sshd-0.4.0-linux-amd64.deb 

Install on Mac

brew install nwtgck/handy-sshd/handy-sshd

Get more executables in the releases.

Examples

# Listen on 2222 and accept user name "john" with password "mypass"
handy-sshd -p 2222 -u john:mypass

# Listen on 2222 and accept user name "john" without password
handy-sshd -p 2222 -u john:

# Listen on 2222 and accept users "john" and "alice" without password
handy-sshd -p 2222 -u john: -u alice:

# Listen on unix domain socket
handy-sshd --unix-socket /tmp/my-unix-socket -u john:

Features

An SSH client can use

• Shell/Interactive shell
• Local port forwarding (ssh -L)
• Remote port forwarding (ssh -R)
• SOCKS proxy (dynamic port forwarding)
• SFTP
• SSHFS
• Unix domain socket (local/remote port forwarding)

All features are enabled by default. You can allow only some of them using permission flags.

Permissions

There are several permissions:

• --allow-direct-streamlocal
• --allow-direct-tcpip
• --allow-execute
• --allow-sftp
• --allow-streamlocal-forward
• --allow-tcpip-forward

All permissions are allowed when nothing is specified. The log shows "allowed: " and "NOT allowed: " permissions as follows:

$ handy-sshd -u "john:"
2023/08/11 11:40:44 INFO listening on :2222...
2023/08/11 11:40:44 INFO allowed: "tcpip-forward", "direct-tcpip", "execute", "sftp", "streamlocal-forward", "direct-streamlocal"
2023/08/11 11:40:44 INFO NOT allowed: none

For example, specifying --allow-direct-tcpip and --allow-execute allows only them:

$ handy-sshd -u "john:" --allow-direct-tcpip --allow-execute
2023/08/11 11:41:03 INFO listening on :2222...
2023/08/11 11:41:03 INFO allowed: "direct-tcpip", "execute"
2023/08/11 11:41:03 INFO NOT allowed: "tcpip-forward", "sftp", "streamlocal-forward", "direct-streamlocal"

--help

Portable SSH server

Usage:
  handy-sshd [flags]

Examples:
# Listen on 2222 and accept user name "john" with password "mypass"
handy-sshd -u john:mypass

# Listen on 22 and accept the user without password
handy-sshd -p 22 -u john:

Permissions:
All permissions are allowed by default.
For example, specifying --allow-direct-tcpip and --allow-execute allows only them.

Flags:
      --allow-direct-streamlocal    client can use Unix domain socket local forwarding (ssh -L)
      --allow-direct-tcpip          client can use local forwarding (ssh -L) and SOCKS proxy (ssh -D)
      --allow-execute               client can use shell/interactive shell
      --allow-sftp                  client can use SFTP and SSHFS
      --allow-streamlocal-forward   client can use Unix domain socket remote forwarding (ssh -R)
      --allow-tcpip-forward         client can use remote forwarding (ssh -R)
  -h, --help                        help for handy-sshd
      --host string                 SSH server host to listen (e.g. 127.0.0.1)
  -p, --port uint16                 port to listen (default 2222)
      --shell string                Shell
      --unix-socket string          Unix domain socket to listen
  -u, --user stringArray            SSH user name (e.g. "john:mypass")
  -v, --version                     show version

Documentation

Index

• func GenerateKey() ([]byte, error)
• type Server
  • func (s *Server) HandleChannels(shell string, chans <-chan ssh.NewChannel)
  • func (s *Server) HandleGlobalRequests(sshConn *ssh.ServerConn, reqs <-chan *ssh.Request)

Functions

func GenerateKey

func GenerateKey() ([]byte, error)

Types

type Server

type Server struct {
	Logger *slog.Logger

	// Permissions
	AllowTcpipForward       bool
	AllowDirectTcpip        bool
	AllowExecute            bool // this should not be split into "allow-exec" and "allow-pty-req" for now because "pty-req" can be used not for shell execution.
	AllowSftp               bool
	AllowStreamlocalForward bool
	AllowDirectStreamlocal  bool
	// contains filtered or unexported fields
}

func (*Server) HandleChannels

func (s *Server) HandleChannels(shell string, chans <-chan ssh.NewChannel)

func (*Server) HandleGlobalRequests

func (s *Server) HandleGlobalRequests(sshConn *ssh.ServerConn, reqs <-chan *ssh.Request)