BebboSSH

WHAT IS THIS?

BebboSSH is an SSH2 implementation for Amiga systems by Stefan "Bebbo"
Franke. This archive is its port to
AROS x86_64 (AROS One 64-bit, ABIv11).
With it you can log in to an AROS machine from any SSH client, run
commands, and copy files with scp and sftp; the native clients connect
from AROS to other SSH servers. The original 68k version is
comm/net/bebbossh.lha; the AROS i386 build is
comm/net/bebbossh.i386-aros.lha.

PROGRAMS

  bebbosshd       SSH2 server: remote commands, SFTP, SCP, TCP port
                  forwarding (direct-tcpip), password and public-key login
  bebbossh        SSH2 client, with -L local port forwarding
  bebboscp        SCP client
  bebbosshkeygen  Ed25519 key generator

Algorithms: curve25519-sha256 key exchange, ssh-ed25519 host and user
keys, aes128-gcm()openssh.com and chacha20-poly1305()openssh.com ciphers.
AES-GCM uses AES-NI and PCLMULQDQ when the CPU provides them.

REQUIREMENTS

- AROS One x86_64 (ABIv11).
- A configured TCP/IP stack (AROSTCP, bsdsocket.library).
- No extra libraries: the crypto code is linked into each program.
- In a virtual machine, use an rtl8139 or pcnet network card, not
  e1000 (see KNOWN LIMITS).

CONTENTS

  BebboSSH/bebbosshd, bebbossh, bebboscp, bebbosshkeygen
  BebboSSH/sshd_config.example, passwd.example
  BebboSSH/README.AROS.txt   install and configuration guide
  BebboSSH/README.md, AROS_PORTING.md, docs/, scripts/
  BebboSSH/COPYING, LICENSE  license texts (GNU GPL v3)
  BebboSSH/SHA256SUMS        checksums of the files above

INSTALLATION

1. Extract the archive to a persistent volume, for example DH0:.
2. In an AROS Shell, create the configuration and a host key:

     cd DH0:BebboSSH
     copy sshd_config.example sshd_config
     copy passwd.example passwd
     bebbosshkeygen -f ssh_host_ed25519_key

3. Edit passwd: one "username password" pair per line. The test/test
   entry of the example is for a first test only; replace it.
4. Start the server:

     stack 262144
     bebbosshd

5. From another machine: ssh username()<address of the AROS machine>

To start the server at boot, add these lines to S:User-Startup:

  Stack 262144
  If EXISTS DH0:BebboSSH/bebbosshd
      Run DH0:BebboSSH/bebbosshd
  EndIf

To call the clients from anywhere, copy bebbossh, bebboscp and
bebbosshkeygen to C:. Keep bebbosshd in its own directory: the example
configuration finds its files through PROGDIR:.

CONFIGURATION

bebbosshd reads ENVARC:ssh/sshd_config if it exists, otherwise
PROGDIR:sshd_config. The main directives of the example:

  Port 22                 TCP port
  ListenAddress 0.0.0.0   address to listen on (0.0.0.0 = all)
  HostKey PROGDIR:ssh_host_ed25519_key
  Passwords PROGDIR:passwd
  HomeDir DH0:            start directory of commands and SFTP
                          (on x86_64 only with BEBBOSSH_AROS_X64_CD set)
  Stack 262144            stack of command tasks (default 1 MiB)
  DebugLevel 1            log level: 0 none to 8 ultra, or a name such
                          as error or debug
  SendNoop some           keepalive messages to idle sessions
  Ciphers aes128-gcm()openssh.com,chacha20-poly1305()openssh.com
                          ciphers offered (both by default)

Command-line options override the file: -p port, -A password file,
-K host key, -H home directory, -v log level (for example -v5).
Public-key login reads ENVARC:.ssh/authorized_keys (OpenSSH format,
one key per line). README.AROS.txt describes every file in detail.

USAGE

From a PC with OpenSSH:

  ssh user()aros-host version
  scp file.txt user()aros-host:DH0:
  sftp user()aros-host

From AROS:

  bebbossh user()host
  bebbossh -i DH0:keys/id_ed25519 user()host command
  bebbossh -L 8080:localhost:80 user()host
  bebboscp localfile user()host:remotefile
  bebbosshkeygen -f DH0:keys/id_ed25519

KNOWN LIMITS

- No full interactive PTY programs: the interactive shell runs simple
  commands, and programs that read their input are rejected with exit
  status 2.
- No redirection or pipes (>, <, |) in remote commands.
- Remote commands run one at a time and block the server until they
  end: keep them short.
- An SFTP path on a volume that is not mounted opens an "insert
  volume" requester and blocks the server until it is closed.
- With an Intel e1000 network card and heavy network load, AROS One
  x86_64 can halt or reboot. The cause is the AROS e1000.device; it is
  fixed upstream (deadwood2/AROS issue 274). Until AROS One ships the
  fix, use an rtl8139 or pcnet card.
- Some features are off unless set before starting bebbosshd
  (setenv NAME 1): BEBBOSSH_AROS_X64_CD (cd and pwd in the interactive
  shell), BEBBOSSH_AROS_X64_SFTP_MTIME (keep upload times),
  BEBBOSSH_AROS_X64_SFTP_LINKS (SFTP readlink and symlink).
- The native client has not been tested on an AROS console yet.
- OpenSSH "put -p" sets the file time before it closes the file, and
  AROS updates the date on close, so that time is not kept.
- passwd.example contains a test password: change it.

WHAT IS NEW IN 1.0.3

- Ctrl-C (Break) stops the server, and it can be started again at once.
- The server reads sshd_config. Without it, the defaults of earlier
  releases apply.
- SendNoop now sends keepalives.
- ListenAddress with a specific address works.
- DebugLevel accepts the numbers used by -v.
- SFTP reads return at most 32736 bytes, the advertised limit.

TESTED

On AROS One x86_64 under QEMU with an rtl8139 card, with the programs
of this archive: OpenSSH ssh, scp and sftp; 100 logins in a row; 80
file transfers without pauses; four servers at once; Ctrl-C and
restart; a server configured only by sshd_config; the native clients;
with and without AES-NI.

SOURCE AND LICENSE

GNU GPL v3 or later (see COPYING). Source of this release:
  https://github.com/kaffeine1/bebbossh-aros/tree/v1.0.3-aros-x86_64
Original BebboSSH: https://franke.ms/git/bebbo/bebbossh
Bug reports: https://github.com/kaffeine1/bebbossh-aros/issues

Port by Michele Dipace <michele.dipace()kaffeine.net>.