参考：https://sb.sb/centos-upgrade-openssl/
yum install gcc gcc-c++ autoconf automake zlib zlib-devel pcre-devel
cd /usr/local/src
wget https://www.openssl.org/source/openssl-1.0.2-latest.tar.gz
tar -xzvf openssl-1.0.2-latest.tar.gz
cd openssl-1.0.2*
./config
make && make install
mv /usr/bin/openssl /tmp/
ln -s /usr/local/ssl/bin/openssl /usr/bin/openssl
openssl version
原文：http://www.cnblogs.com/flowjacky/p/7168192.html