编译安装OpenSSL
Ubuntu 18.04.1 LTS 自带的 OpenSSL版本是 openssl 1.1.0g，因为 Nginx 支持 TLS 1.3 至少需要 OpenSSL 1.1.1 或者更高，所以需要源码编译下。
卸载系统自带OpenSSL
# 删除软件及其配置文件
# apt-get --purge remove <package>
apt-get --purge remove openssl安装依赖
apt-get update
apt-get install build-essential checkinstall zlib1g-dev -y ####下载源码
cd /usr/local/src/
wget https://www.openssl.org/source/openssl-1.1.1b.tar.gz
tar -zxvf openssl-1.1.1b.tar.gz
下载源码
wget --no-check-certificate https://www.openssl.org/source/openssl-1.1.1c.tar.gz
tar -zxvf openssl-1.1.1c.tar.gz ####编译安装
cd openssl-1.1.1b
./config --prefix=/usr/local/ssl --openssldir=/usr/local/ssl shared zlib
make && make install
编译安装
cd openssl-1.1.1c
./config --prefix=/usr/local/openssl #编译生成文件位置
make && make install命令软链【或添加环境变量均可】
# mv /usr/bin/openssl /usr/bin/openssl.bak 在卸载时已经删除
ln -sv /usr/local/openssl/bin/openssl /usr/bin/openssl
# mv /usr/include/openssl /usr/include/openssl.bak 在卸载时已经删除
ln -sv /usr/local/openssl/include/openssl /usr/include/openssl ####配置链接库
cd /etc/ld.so.conf.d/
vim openssl-1.1.1c.conf
# Paste the openssl library path directory.
/usr/local/ssl/lib
# Save and exit.
ldconfig -v
配置链接库
cd /etc/ld.so.conf.d/
vim openssl-1.1.1c.conf
# Paste the openssl library path directory.
/usr/local/openssl/lib
# Save and exit.
ldconfig -v And you will see the OpenSSL libraries on the '/usr/local/ssl/lib' directory has been loaded.
####配置 OpenSSL 库
vim /etc/environment
# Now add the new OpenSSL binary directory as below
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/local/ssl/bin"
# Save and exit.
# Reload the environment file and test new updated binary PATH.
source /etc/environment
echo $PATH
Now check again the OpenSSL binary file.
which openssl
####报错
当你完成上述步骤，然后执行openssl version，然后就报错了......
Github上有专门的issue`OPENSSL_1_1_1' not found (required by openssl) #5845
主要是LD_LIBRARY_PATH这个环境变量没有指定，所以导致openssl正在使用旧的系统OpenSSL库
openssl:/usr/lib/libssl.so.1.1: versionOPENSSL_1_1_1' not found (required by openssl)`
openssl:/usr/lib/libcrypto.so.1.1: versionOPENSSL_1_1_1' not found (required by openssl)`
这个时候你需要找到你新安装的openssl的位置
which openssl
/usr/local/ssl/bin/openssl
看看它的上级目录有没有lib
我这里按照我的实际情况，执行
echo "export LD_LIBRARY_PATH=/usr/local/ssl/lib" >> ~/.bashrc
export LD_LIBRARY_PATH=/usr/local/ssl/lib
然后再次查看 openssl version
OpenSSL 1.1.1c 28 May 2019
参考资料：
How to Install the latest OpenSSL version from Source on Linux
安装openssl报错openssl: /usr/lib/x86_64-linux-gnu/libssl.so.1.1: version `OPENSSL_1_1_1' not found