remote server

• SSH port 22
• telnet port 23

telnet :23

Perbedaan Utama Antara Telnet dan SSH Telnet tidak menyediakan autentikasi, sedangkan SSH mengautentikasi penerima. Jaringan pribadi berfungsi dengan Telnet, sedangkan SSH beroperasi pada jaringan bersama. Telnet berinteraksi melalui TCP/IP melalui nomor port 23, sedangkan SSH menggunakan nomor port 22 untuk komunikasi.

install telnet

• apt install telnet

host windows / termux

• telnet 192.168.1.1

ssh :22

• SSH adalah Secure Shell, yaitu sebuah protokol yang memungkinkan kamu untuk mengontrol perangkat, termasuk mengakses dan memodifikasi beragam pengaturan file yang ada dalam server dalam jarak jauh.

install ssh

• apt install openssh-server
• konfigurasi ssh /etc/ssh/
  • nano /etc/ssh/sshd_config

    port 22
    

• start ssh server
  • systemctl restart ssh or /etc/init.d/ssh restart
  • systemctl status/start/stop/enable/disable ssh
• host / client
  • ssh user@192.168.1.1 -p 22
  • ssh user@192.168.1.1 -x "ls; pwd; cd /home/ariafatah; mkdir test"

remote with keygen

make ssh keygen

ssh-keygen -t rsa
scp path_to_path/.ssh/id.rsa.pub user@server:/home/user/.ssh/authorized_keys
scp path_to_path/.ssh/id.rsa.pub user@server:/home/user/.ssh/windows.keys

authorized keys

• cd /etc/ssh/sshd.conf
• and add this

  AuthorizedKeysFile  /home/ariafatah/.ssh/windows.keys
  

• systemctl restart sshd

server / client

make keygen

• ssh-keygen
• ssh-keygen -t RSA / -t DSA / -t ECDSA (opsional)
• add file and put pass every login
  • Enter file in which to save the key (/root/.ssh/id_rsa): (u can enter or add path manual)
  • Enter passphrase (empty for no passphrase): (opsional)
• check key

  Your identification has been saved in /root/.ssh/id_rsa
  Your public key has been saved in /root/.ssh/id_rsa.pub
  

• cat /root/.ssh/id_rsa.pub
  • and copy key and put to authorized_keys
  • and u can use in client

client

• scp C:\Users\ariaf\.ssh\id_rsa.pub ariafatah@192.168.1.1:/home/ariafatah/.ssh/authorized_keys
• ssh-copy-id -i /root/.ssh/id_rsa.pub user@<destination_ip>
• ssh-copy-id -i /lokasi/ke/kunci.pub user@server

use to remote ssh

• ssh -i user_cert user@server_address

• ssh -OPTIONS -p SSH_PORT user@remote_server "remote_command1; remote_command2; remote_script.sh"

• inget id_rsa yang dikirim pub
• lalu untuk fileyang di .ssh/authorized_keys nya harus 700 dan harus milih user
  • (group dan other tidak boleh ada permissions)

hardening ssh

• server
  • jika ingin sshnya hanya bisa di akses lewat id_rsa
  • bisa tambahkan aturan di /etc/ssh/sshd_conf

    PasswordAuthentication no
    

• firewall
  • sudo firewall-cmd --add-port=1026/tcp --permanent successsudo firewall-cmd --remove-service=ssh --permanent success