Moved  : https://codeberg.org/vaporup/ssh-tools
Reason : https://github.blog/2023-03-09-raising-the-bar-for-software-security-github-2fa-begins-march-13/

ssh-tools

Making SSH more convenient

ssh-ping

Check if host is reachable using ssh_config

• Outputs Reply from when server is reachable but login failed
• Outputs Pong from when server is reachable and login was successful

$ ssh-ping -c 3 kim

SSHPING kim
Reply from kim: ssh_seq=1 time=109 ms
Reply from kim: ssh_seq=2 time=136 ms
Reply from kim: ssh_seq=3 time=141 ms

--- kim ping statistics ---
3 requests transmitted, 3 requests received, 0% request loss

TAB Completions

Ubuntu (and maybe other distros) ship completions for ssh which can be re-used:

Bash

complete -F _known_hosts ssh-ping

Zsh

compdef _ssh_hosts ssh-ping

Fish

complete -c ssh-ping -a "(__fish_print_hostnames)"

ssh-last

Like last but for SSH sessions

# ssh-last

LOGIN            LOGOUT           DURATION   USER   HOST         PORT   AUTH_ID
Aug 14 03:45:34  Aug 14 03:48:06  00:02:32   swick  JumpHost     40548  (C) swick@company
Aug 26 22:20:02  Aug 26 22:20:02  00:00:00   swick  192.168.1.5  48856  (?) password
Oct 14 13:43:49  Oct 14 13:44:29  00:00:40   root   192.168.1.5  45828  (K) [email protected]
Nov 02 12:16:58  still logged in  241:22:12  swick  192.168.1.5  59198  (K) SSHFS Mount

More info at the docs

ssh-certinfo

Shows validity and information of SSH certificates

$ ssh-certinfo ~/.ssh/*.pub

/home/vaporup/.ssh/id_rsa-cert.pub  SSH_CERT_VALID    forever              ->  forever
/home/vaporup/.ssh/test1-cert.pub   SSH_CERT_INVALID  2038-01-19T04:14:07  ->  2038-01-19T04:14:07
/home/vaporup/.ssh/test2-cert.pub   SSH_CERT_EXPIRED  1988-11-14T13:36:40  ->  1991-08-11T14:36:40

$ ssh-certinfo -v ~/.ssh/*.pub

/home/vaporup/.ssh/id_rsa-cert.pub:
        Type: [email protected] user certificate
        Public key: RSA-CERT SHA256:Mm7o312345YEaWetVshTBslX48h0XJceLWzxx3RugDg
        Signing CA: RSA SHA256:4fcOpOm/Xk12345mYnihk0cr6SdjghPgONxriMJex+A
        Key ID: "vaporup"
        Serial: 0
        Valid: forever
        Principals: (none)
        Critical Options: (none)
        Extensions:
                permit-X11-forwarding
                permit-agent-forwarding
                permit-port-forwarding
                permit-pty
                permit-user-rc

ssh-force-password

Enforces password authentication (as long as the server allows it).
It became quite annoying googling the SSH options for this every time.
e.g. used to skip key-based login for password testing.

$ ssh-force-password kim

vaporup@kim's password:

ssh-keyinfo

Prints keys in several formats

$ ssh-keyinfo ~/.ssh/*.pub

(RSA)  2048     MD5 40:52:aa:14:a5:9a:fe:b5:96:c0:d2:dc:99:f1:a5:77  /home/vaporup/.ssh/id_rsa.pub
(RSA)  2048  SHA256 V4F6ipY4gG83sQGM0eRk0+g1RWE9K4asDUj1jFpCa48      /home/vaporup/.ssh/id_rsa.pub

ssh-hostkeys

Prints server host keys in several formats

$ ssh-hostkeys kim

  (ECDSA)   256     MD5 3d:8e:49:6e:40:34:c6:e4:c8:5f:60:d9:ad:bf:1f:b9
  (ECDSA)   256  SHA256 txYpmPENBWolKBaA5EkCM/y1Hm2DP81jtABFrWUBf/c
(ED25519)   256     MD5 a8:93:71:f9:13:d0:32:02:c0:e5:1e:f6:b9:db:8c:b0
(ED25519)   256  SHA256 JZMLzNS2ifdGYv2SrqDodz7+/qaRCTBPukaCnMQqbX8
    (RSA)  2048     MD5 8b:37:63:cd:58:fd:9c:18:93:08:3a:4c:84:64:87:91
    (RSA)  2048  SHA256 WkOzD8BaeljejgTTAwECkByyb4kHdI0pnJB2/gcS1Lk

ssh-facts

Get some facts about the remote system

$ ssh-facts kim

OS=ubuntu
OS_VERSION=16.04
UPTIME=7 days, 22 hours, 25 minutes
LAST_REBOOT=Dec 20 19:34:27 2018
CPU_CORES=2
CPU_SOCKETS=2
HOSTNAME=kim
KERNEL_NAME=Linux
MACHINE=x86_64
MACHINE_TYPE=virtual_by_kvm
MEMORY=4045996
INIT=systemd
LSB_CODENAME=xenial
LSB_DESCRIPTION=Ubuntu 16.04.5 LTS
LSB_ID=Ubuntu
LSB_RELEASE=16.04

ssh-diff

Diff a file over SSH

$ ssh-diff /etc/hosts kim

Comparing kim:/etc/hosts (<) with /etc/hosts (>)

1,2c1,2
< 127.0.0.1 localhost
< 127.0.1.1 kim
---
> 127.0.0.1 localhost
> 127.0.1.1 blinky

ssh-version

Shows version of the SSH server you are connecting to

$ ssh-version kim

Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu2.6

Packages