# 定义变量
dir="/etc/xinetd.d/"
sshd_pid=`ps -ef |grep sshd |awk '$3==1 {print $2}'`

# 结束sshd进程
stop_sshd(){
	[ -z "${sshd_pid}" ] || {
		kill ${sshd_pid}
	}
}

# 下载telnet
apt_telnet(){
  apt install -y openbsd-inetd telnetd
}

# 检查目录
check_dic(){
    [ ! -d $dir ] && {
	    mkdir -p $dir
	}
}

cfg_start_telnet(){

# telnet 配置文件
cat>/etc/xinetd.d/telnet<<'EOF'
service telnet  
{  
    disable         = no  
    flags           = REUSE  
    socket_type     = stream  
    wait            = no  
    user            = root  
    server          = /usr/sbin/in.telnetd  
    log_on_failure  += USERID  
}
EOF

# 启动telnet
systemctl enable  inetd
systemctl restart  inetd
# systemctl is-enabled  inetd

}

# 添加用户(telnet配置用户)
user_add(){
  useradd xk3
  echo "xk3:1" | chpasswd
  echo  'xk3 ALL=(ALL)  NOPASSWD: ALL '  >>/etc/sudoers
}
 

# 编译安装
make_install_new_sshd(){
  # 安装依赖 
  apt install -y gcc zlib1g zlib1g-dev   libssl-dev  make 

  # 下载解压sshd
  wget  https://mirrors.aliyun.com/pub/OpenBSD/OpenSSH/portable/openssh-9.6p1.tar.gz
  tar xf openssh-9.6p1.tar.gz 
  cd openssh-9.6p1/
  ll

  # 编译安装
  ./configure  --prefix=/app/tools/openssh-9.6p1/ 
  nproc 
  make -j `nproc` 
  make install 

  # 创建软连接
  ln -s  /app/tools/openssh-9.6p1/  /app/tools/openssh

  # 结束sshd进程
  stop_sshd
}

#pkill sshd


#telnet 10.0.0.37 23 #10.0.0.5为服务器ip   
#输入xk3
#和输入密码 

cfg_start_new_sshd(){
  # 修改新ssh配置文件
  cp /app/tools/openssh/etc/sshd_config{,.bak}
cat >>/app/tools/openssh/etc/sshd_config <<EOF
Port 22
PermitRootLogin yes
PasswordAuthentication yes
#GSSAPIAuthentication no 这个不用配置,默认就关闭了.
UseDNS no
EOF

  # 启动服务测试 
  /app/tools/openssh/sbin/sshd

  # 关闭并删除openssh 8.2版本的服务端
  dpkg -l |grep openssh |awk '{print $2}' |xargs dpkg --purge

  # 配置PATH环境变量
  echo 'export PATH=/app/tools/openssh/bin/:/app/tools/openssh/sbin/:$PATH' >>/etc/profile 
  source  /etc/profile

  #2.检查命令位置
  which ssh ssh-keygen sshd


  # 将sshd添加到systemctl中
  useradd  -s /sbin/nologin -M  sshd 

cat>/usr/lib/systemd/system/sshd.service<<'EOF'
[Unit]
Description=OpenSSH 9.6 server daemon
Documentation=man:sshd(8) man:sshd_config(5)
After=network.target 

[Service]
Type=simple
ExecStart=/app/tools/openssh/sbin/sshd -D
ExecReload=/bin/kill -HUP $MAINPID
KillMode=process
Restart=on-failure
RestartSec=42s

[Install]
WantedBy=multi-user.target
EOF

  # 结束sshd进程
  # pkill sshd 
  stop_sshd
  systemctl daemon-reload 
  systemctl enable  --now  sshd 

  # 关闭telnet仅使用sshd
  systemctl disable  --now  inetd
}
main(){
  apt_telnet
  check_dic
  make_install_new_sshd
  cfg_start_new_sshd
}

main

 升级到openssh-9.x版本后ssh-copy-id.无法使用问题解决
#1. 复制源码包里的ssh-copy-id命令到bin目录下
cp openssh-9.9p1/contrib/ssh-copy-id     /app/tools/openssh/bin/

#2.给x权限 
 chmod  +x /app/tools/openssh/bin/ssh-copy-id
 
#3.检查PATH
echo $PATH是否有 上面的bin目录 

#4.测试ssh-copy-id是否可用 
 ssh-copy-id   web01
/app/tools/openssh/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
/app/tools/openssh/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/app/tools/openssh/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys

Authorized users only. All activities may be monitored and reported.
root@web01's password: 

Number of key(s) added: 1

Now try logging into the machine, with: "ssh 'web01'"
and check to make sure that only the key(s) you wanted were added.

#5.检查秘钥认证
ssh web01  hostname -I 

Authorized users only. All activities may be monitored and reported.
10.0.0.69 172.16.1.69