本部分内容中CA（Certificate Authority）均代表数字证书认证机构。

如果已经有搭建的CA，请跳过此步骤。

CA服务器为TLS安全性保证的关键节点，请客户自行构建CA服务器，本流程仅供测试使用，安全性不保证。

选择一台服务器做为CA，创建如下目录及文件。

mkdir -p /opt/gcache/secure/CACerts
mkdir -p /opt/gcache/secure/CACerts/certs
mkdir -p /opt/gcache/secure/CACerts/crl
mkdir -p /opt/gcache/secure/CACerts/csr
mkdir -p /opt/gcache/secure/CACerts/newcerts
mkdir -p /opt/gcache/secure/CACerts/private
mkdir -p /opt/gcache/secure/CACerts/public
touch /opt/gcache/secure/CACerts/index.txt
echo 01 > /opt/gcache/secure/CACerts/serial

拷贝位于系统目录的openssl.conf并修改。

cp /etc/pki/tls/openssl.cnf /opt/gcache/secure/CACerts/openssl.cnf
chmod 600 /opt/gcache/secure/CACerts/openssl.cnf
vi /opt/gcache/secure/CACerts/openssl.cnf

修改如下内容（有则修改，无则添加）。

[ CA_default ]
dir             = /opt/gcache/secure/CACerts
certs           = $dir/certs
crl_dir         = $dir/crl
unique_subject  = no
certificate	= $certs/ca.crt
crl		= $crl_dir/crl.pem
private_key	= $dir/private/ca.self
default_md	= default

[ req ]
default_md		= sm3

[ v3_req ]
keyUsage = nonRepudiation, digitalSignature

[ v3enc_req ]
# Extensions to add to a certificate request
basicConstraints = CA:FALSE
keyUsage = keyAgreement, keyEncipherment, dataEncipherment

[ v3_ca ]
keyUsage = cRLSign, keyCertSign

CA节点生成公私钥，生成公私钥时请输入CA密码，保证密码复杂度。因为后续执行证书签发需要此密码，请妥善保存。
```
cd /opt/gcache/secure/CACerts
openssl genrsa -aes256 -out private/ca.self 4096
```
```
openssl rsa -in private/ca.self -pubout -out public/ca.common
```

CA节点为自己签发证书。

openssl req -new -x509 -key private/ca.self -days 3650 -out certs/ca.crt -subj "/C=CN/ST=HZ/L=Binjiang/O=Huawei/CN=GCACHED"

数字证书认证机构配置