一、环境介绍
查看openssh、openssl版本 [root@localhost ~]# openssl version OpenSSL 1.0.2k-fips 26 Jan 2017 [root@localhost ~]# ssh -V OpenSSH_7.4p1, OpenSSL 1.0.2k-fips 26 Jan 2017
查看linux发行版和内核 [root@localhost ~]# cat /etc/os-release NAME="CentOS Linux" VERSION="7 (Core)" ID="centos" ID_LIKE="rhel fedora" VERSION_ID="7" PRETTY_NAME="CentOS Linux 7 (Core)" ANSI_COLOR="0;31" CPE_NAME="cpe:/o:centos:centos:7" HOME_URL="https://www.centos.org/" BUG_REPORT_URL="https://bugs.centos.org/" CENTOS_MANTISBT_PROJECT="CentOS-7" CENTOS_MANTISBT_PROJECT_VERSION="7" REDHAT_SUPPORT_PRODUCT="centos" REDHAT_SUPPORT_PRODUCT_VERSION="7" [root@localhost ~]# uname -r 3.10.0-957.el7.x86_64
二、安装配置telnet
2.1、安装telnet-server
[root@localhost ~]# yum -y install xinetd telnet-server
2.2、配置telnet
`先看一下xinetd.d目录下是否有telnet文件` [root@localhost ~]# ll /etc/xinetd.d/telnet ls: cannot access /etc/xinetd.d/telnet: No such file or directory `如果有，则将文件里面的disable = no改成disable = yes` `如果没有，就进行下面的操作` [root@localhost ~]# cat > /etc/xinetd.d/telnet <<EOF service telnet { disable = yes flags = REUSE socket_type = stream wait = no user = root server = /usr/sbin/in.telnetd log_on_failure += USERID } EOF
2.3、配置telnet登录的终端类型
[root@localhost ~]# cat >> /etc/securetty <<EOF pts/0 pts/1 pts/2 pts/3 EOF
2.4、启动telnet服务
[root@localhost ~]# systemctl enable xinetd --now [root@localhost ~]# systemctl enable telnet.socket --now [root@localhost ~]# ss -nltp | grep 23 LISTEN 0 128 :::23 :::* users:(("systemd",pid=1,fd=46)) `23端口起来了，表示telnet服务正常运行`
三、切换登录方式为telnet
后面的操作都是在telnet链接的方式下进行，避免ssh中断导致升级失败
以telnet方式登录的时候，注意选择协议和端口，协议为telnet，端口为23
四、开始升级OpenSSH
4.1、下载升级所需依赖包
[root@localhost ~]# yum -y install gcc gcc-c++ glibc make autoconf openssl openssl-devel pcre-devel pam-devel
4.2、下载OpenSSL和OpenSSH
openssl官网：https://www.openssl.org/
openssh官网：http://www.openssh.com/
[root@localhost ~]# wget https://www.openssl.org/source/openssl-1.1.1i.tar.gz [root@localhost ~]# wget http://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-8.6p1.tar.gz [root@localhost ~]# tar xf openssl-1.1.1i.tar.gz [root@localhost ~]# tar xf openssh-8.6p1.tar.gz
4.3、编译安装OpenSSL
`开始之前，先备份一下原有的OpenSSL文件` [root@localhost ~]# mv /usr/bin/openssl{,.bak} [root@localhost ~]# mv /usr/include/openssl{,.bak}
[root@localhost ~]# cd openssl-1.1.1i/ [root@localhost openssl-1.1.1i]# ./config shared && make && make install
`编译完成后，可以在/usr/local目录下找到openssl的二进制文件和目录` [root@localhost ~]# ll /usr/local/bin/openssl -rwxr-xr-x 1 root root 749136 Jan 14 14:25 /usr/local/bin/openssl [root@localhost ~]# ll -d /usr/local/include/openssl/ drwxr-xr-x 2 root root 4096 Jan 14 14:25 /usr/local/include/openssl/
`建立软连接` [root@localhost ~]# ln -s /usr/local/bin/openssl /usr/bin/openssl [root@localhost ~]# ln -s /usr/local/include/openssl/ /usr/include/openssl [root@localhost ~]# ll /usr/bin/openssl lrwxrwxrwx 1 root root 22 Jan 14 14:32 /usr/bin/openssl -> /usr/local/bin/openssl [root@localhost ~]# ll -d /usr/include/openssl lrwxrwxrwx 1 root root 27 Jan 14 14:33 /usr/include/openssl -> /usr/local/include/openssl/
`重新加载配置，验证openssl版本` [root@localhost ~]# echo "/usr/local/lib64" >> /etc/ld.so.conf [root@localhost ~]# /sbin/ldconfig [root@localhost ~]# openssl version OpenSSL 1.1.1i 8 Dec 2020
4.3.1、可能会有的一些报错和解决方法
[root@localhost ~]# openssl version
openssl: error while loading shared libraries: libssl.so.1.1: cannot open shared object file: No such file or directory "这是因为libssl.so.1.1文件找不到，执行find / -name 'libssl.so.1.1'，将/etc/ld.so.conf里面的lib64改成find出来的路径即可"
[root@localhost ~]# find / -name "openssl" "编译完，可以用上面的find命令看一下openssl所在的路径，以及include/openssl所在的路径"
4.4、编译安装OpenSSH
`备份原有的ssh目录`
[root@localhost ~]# mv /etc/ssh{,.bak} [root@localhost ~]# mkdir /usr/local/openssh [root@localhost ~]# cd openssh-8.4p1/ [root@localhost openssh-8.4p1]# ./configure --prefix=/usr/local/openssh \ --sysconfdir=/etc/ssh \ --with-openssl-includes=/usr/local/include \ --with-ssl-dir=/usr/local/lib64 \ --with-zlib \ --with-md5-passwords \ --with-pam && \ make && \ make install
4.4.1、配置sshd_config文件
[root@localhost ~]# echo "UseDNS no" >> /etc/ssh/sshd_config [root@localhost ~]# echo 'PermitRootLogin yes' >> /etc/ssh/sshd_config [root@localhost ~]# echo 'PubkeyAuthentication yes' >> /etc/ssh/sshd_config [root@localhost ~]# echo 'PasswordAuthentication yes' >> /etc/ssh/sshd_config
`如果是图形化界面，需要x11的话，需要配置如下` [root@localhost ~]# echo "X11Forwarding yes" >> /etc/ssh/sshd_config [root@localhost ~]# echo "X11UseLocalhost no" >> /etc/ssh/sshd_config [root@localhost ~]# echo "XAuthLocation /usr/bin/xauth" >> /etc/ssh/sshd_config
4.4.2、创建新的sshd二进制文件
[root@localhost ~]# mv /usr/sbin/sshd{,.bak} [root@localhost ~]# mv /usr/bin/ssh{,.bak} [root@localhost ~]# mv /usr/bin/ssh-keygen{,.bak} [root@localhost ~]# ln -s /usr/local/openssh/bin/ssh /usr/bin/ssh [root@localhost ~]# ln -s /usr/local/openssh/bin/ssh-keygen /usr/bin/ssh-keygen [root@localhost ~]# ln -s /usr/local/openssh/sbin/sshd /usr/sbin/sshd `查看openssh当前版本` [root@localhost ~]# ssh -V OpenSSH_8.4p1, OpenSSL 1.1.1i 8 Dec 2020
4.4.3、重新启动openssh服务
[root@localhost ~]# systemctl disable sshd --now [root@localhost ~]# mv /usr/lib/systemd/system/sshd.service{,.bak} [root@localhost ~]# systemctl daemon-reload [root@localhost ~]# cp -a openssh-8.6p1/contrib/redhat/sshd.init /etc/init.d/sshd [root@localhost ~]# cp -a openssh-8.6p1/contrib/redhat/sshd.pam /etc/pam.d/sshd.pam [root@localhost ~]# chkconfig --add sshd [root@localhost ~]# systemctl enable sshd --now
4.5、ssh链接成功后的处理
[root@localhost ~]# ssh root@192.168.****** `成功连接上之后，可以关闭telnet服务，当然，也可以不关闭` [root@localhost ~]# systemctl disable xinetd.service --now [root@localhost ~]# systemctl disable telnet.socket --now