1：简介
最近浙江电信对线上服务器进行漏洞扫描，暴露出原有的openssh有漏洞，建议升级openssh版本；
2：操作环境
Red Hat Enterprise Linux Server release 6.4
3：所需软件包
（1）gcc zlib zlib-devel make pam pam-devel (升级过程中所需依赖包)
（2）dropbear-2014.66.tar.bz2（代替原有用pm包安装openssh环境）
（3）openssh-6.7.tar.gz（升级的软件包）
4：操作过程
（1）安装dropbear包代替openssh
[[email protected] ~]#tar -xvf dropbear-2014.66.tar.bz2
[[email protected] ~]# cd dropbear-2014.66
[[email protected] dropbear-2014.66]#./configure --prefix=/usr/local/dropbear
[[email protected] dropbear-2014.66]# make
[[email protected] dropbear-2014.66]#make install
[[email protected] ~]# mkdir /etc/dropbear
[[email protected] ~]#/usr/local/dropbear/bin/dropbearkey -t rsa -s 2048 -f /etc/dropbear/dropbear_rsa_host_key
Generating key, this may take a while...
Public key portion is:
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCCBQJeoEhvNKkoEO3Y43++TOJl6dneodImEqnfyrfeFpjPQatYH5aQTxghO71KptR5pWYitdRarUcBJGw1fKsfhpwa6is6n6/YyQ2VljqFV+2caHSM3MxmPUHx+A6fzBbvw8u9kDFBz22xXKKSeNpmUyzqvXw8xxt2iu24kkvUYfGfxcHUyauFyiwEDBtz3JbfxlNpTO7eggMi0FT1Q8ndpgf2rg1FbflPweYjjuEtJwqEP6z0CHBsK5/KOAeanlhrkGiJ7EtyP19JxLinNWQeenknERA9IOWox928BjE3ZQ8Fa3JqAQg/w9jNNaugTgxedeLxn897DQBe9lgaatwR [email protected]
Fingerprint: md5 dd:75:10:cf:a0:0f:19:96:bd:49:69:05:ab:d6:d6:51
[[email protected] ~]# /usr/local/dropbear/sbin/dropbear -p 1213
[[email protected] ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 809/rpcbind
tcp 0 0 192.168.122.1:53 0.0.0.0:* LISTEN 1281/dnsmasq
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1651/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1123/master
tcp 0 0 0.0.0.0:1213 0.0.0.0:* LISTEN 8037/dropbear
tcp 0 0 0.0.0.0:40328 0.0.0.0:* LISTEN 827/rpc.statd
tcp 0 0 :::111 :::* LISTEN 809/rpcbind
tcp 0 0 :::59889 :::* LISTEN 827/rpc.statd
tcp 0 0 :::22 :::* LISTEN 1651/sshd
tcp 0 0 ::1:25 :::* LISTEN 1123/master
tcp 0 0 :::1213 :::* LISTEN 8037/dropbear
tcp 0 0 :::3306 :::* LISTEN 14315/mysqld
udp 0 0 0.0.0.0:1003 0.0.0.0:* 827/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 809/rpcbind
udp 0 0 0.0.0.0:38790 0.0.0.0:* 827/rpc.statd
udp 0 0 192.168.122.1:53 0.0.0.0:* 1281/dnsmasq
udp 0 0 0.0.0.0:67 0.0.0.0:* 1281/dnsmasq
udp 0 0 0.0.0.0:984 0.0.0.0:* 809/rpcbind
udp 0 0 :::111 :::* 809/rpcbind
udp 0 0 :::40854 :::* 827/rpc.statd
udp 0 0 :::984 :::* 809/rpcbind
注：以上操作，已经做到替代原有的openssh软件，还需要注意的是关闭防火墙；或者放行1213端口，该端口是我们任意指定；
5：dropbear环境测试
操作方法：
登陆别的主机对该主机进行ssh登陆
[[email protected] ~]# ssh -p1213 192.168.10.120
The authenticity of host ‘192.168.10.120 (192.168.10.120)‘ can‘t be established.
RSA key fingerprint is 46:de:1b:14:42:5d:83:56:d6:29:15:13:c2:b2:d6:05.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.10.120‘ (RSA) to the list of known hosts.
[email protected]‘s password:
Last login: Tue Feb 3 10:18:15 2015 from 192.168.10.130
说明：测试主机地址：192.168.10.130，升级主机地址：192.168.10.120
6：升级openssh
（1）操作步骤
[[email protected] ~]# mv /etc/ssh /etc/ssh.bak
[[email protected] ~]# rpm -qa |grep openssh
openssh-server-5.3p1-84.1.el6.x86_64
openssh-5.3p1-84.1.el6.x86_64
openssh-clients-5.3p1-84.1.el6.x86_64
[[email protected] ~]# rpm -e --nodeps `rpm -qa |grep openssh`
[[email protected] ~]# tar -xvf openssh-6.7p1.tar.gz
[[email protected] openssh-6.7p1]# ./configure --prefix=/usr --sysconfdir=/etc/ssh --with-pam --with-zlib --with-md5-passwords
[[email protected] openssh-6.7p1]#make
[[email protected] openssh-6.7p1]#make install
[[email protected] ~]# /usr/sbin/sshd -t -f /etc/ssh/sshd_config
[[email protected] openssh-6.7p1]# ssh -V
OpenSSH_6.7p1, OpenSSL 1.0.0-fips 29 Mar 2010
[[email protected] openssh-6.7p1]# cp contrib/redhat/sshd.init /etc/init.d/sshd
[[email protected] openssh-6.7p1]# /etc/init.d/sshd start
[[email protected] ~]# killall dropbear
[[email protected] ~]# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 809/rpcbind
tcp 0 0 192.168.122.1:53 0.0.0.0:* LISTEN 1281/dnsmasq
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 20720/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1123/master
tcp 0 0 0.0.0.0:40328 0.0.0.0:* LISTEN 827/rpc.statd
tcp 0 0 :::111 :::* LISTEN 809/rpcbind
tcp 0 0 :::59889 :::* LISTEN 827/rpc.statd
tcp 0 0 :::22 :::* LISTEN 20720/sshd
tcp 0 0 ::1:25 :::* LISTEN 1123/master
tcp 0 0 :::3306 :::* LISTEN 14315/mysqld
udp 0 0 0.0.0.0:1003 0.0.0.0:* 827/rpc.statd
udp 0 0 0.0.0.0:111 0.0.0.0:* 809/rpcbind
udp 0 0 0.0.0.0:38790 0.0.0.0:* 827/rpc.statd
udp 0 0 192.168.122.1:53 0.0.0.0:* 1281/dnsmasq
udp 0 0 0.0.0.0:67 0.0.0.0:* 1281/dnsmasq
udp 0 0 0.0.0.0:984 0.0.0.0:* 809/rpcbind
udp 0 0 :::111 :::* 809/rpcbind
udp 0 0 :::40854 :::* 827/rpc.statd
udp 0 0 :::984 :::* 809/rpcbind
[[email protected] openssh-6.7p1]# /etc/init.d/sshd start
/sbin/restorecon: lstat(/etc/ssh/ssh_host_ecdsa_key.pub) failed: No such file or directory
Starting sshd:[ OK ]
[[email protected] openssh-6.7p1]# service sshd start
/sbin/restorecon: lstat(/etc/ssh/ssh_host_ecdsa_key.pub) failed: No such file or directory
Starting sshd:[ OK ]
[[email protected] openssh-6.7p1]# service sshd status
sshd (pid 20720) is running...
[[email protected] openssh-6.7p1]# chkconfig --add sshd
[[email protected] openssh-6.7p1]# chkconfig --list sshd
sshd 0:off 1:off 2:on 3:on 4:on 5:on 6:off