De forma predeterminada, Docker se ejecuta a través de sockets UNIX no conectados a la red. También puede utilizar sockets HTTP para comunicación opcional.
Si necesita acceder a Docker a través de la red de forma segura, puede habilitar TLS apuntando el logotipo de Docker a un certificado de CA de confianza especificando una bandera.
En modo daemon, solo permite conexiones de clientes verificados por un certificado firmado por la CA. En modo cliente, solo se conecta a servidores con certificados firmados por la CA.
# 创建CA证书目录
[root@localhost ~]# mkdir tls
[root@localhost ~]# cd tls/
# 创建CA密钥
[root@localhost tls]# openssl genrsa -aes256 -out ca-key.pem 4096
Generating RSA private key, 4096 bit long modulus
..............................................................................++
.....................................................................................................................................................................++
e is 65537 (0x10001)
Enter pass phrase for ca-key.pem:
Verifying - Enter pass phrase for ca-key.pem:
# 创建CA证书
[root@localhost tls]# openssl req -new -x509 -days 1000 -key ca-key.pem -sha256 -subj "/CN=*" -out ca.pem
Enter pass phrase for ca-key.pem:
[root@localhost tls]# ll
总用量 8
-rw-r--r--. 1 root root 3326 12月 3 17:20 ca-key.pem
-rw-r--r--. 1 root root 1765 12月 3 19:03 ca.pem
# 创建服务器私钥
[root@localhost tls]# openssl genrsa -out server-key.pem 4096
Generating RSA private key, 4096 bit long modulus
................................................................++
..................++
e is 65537 (0x10001)
[root@localhost tls]# ll
总用量 12
-rw-r--r--. 1 root root 3326 12月 3 17:20 ca-key.pem
-rw-r--r--. 1 root root 1765 12月 3 19:03 ca.pem
-rw-r--r--. 1 root root 3243 12月 3 19:03 server-key.pem
# 对私钥进行签名
[root@localhost tls]# openssl req -subj "/CN=*" -sha256 -new -key server-key.pem -out server.csr
[root@localhost tls]# ll
总用量 16
-rw-r--r--. 1 root root 3326 12月 3 17:20 ca-key.pem
-rw-r--r--. 1 root root 1765 12月 3 19:03 ca.pem
-rw-r--r--. 1 root root 1574 12月 3 19:04 server.csr
-rw-r--r--. 1 root root 3243 12月 3 19:03 server-key.pem
使用CA证书与私钥签名,输入上面设置的密码
[root@localhost tls]# openssl x509 -req -days 1000 -sha256 -in server.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out server-cert.pem
Signature ok
subject=/CN=*
Getting CA Private Key
Enter pass phrase for ca-key.pem:
#生成客户端密钥
[root@localhost tls]# openssl genrsa -out key.pem 4096
Generating RSA private key, 4096 bit long modulus
....................................................................................................................++
.................................++
e is 65537 (0x10001)
#对客户端签名
[root@localhost tls]# openssl req -subj "/CN=client" -new -key key.pem -out client.csr
#创建配置文件
[root@localhost tls]# echo extendedKeyUsage=clientAuth > extfile.cnf
#签名证书
[root@localhost tls]# openssl x509 -req -days 1000 -sha256 -in client.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out cert.pem -extfile extfile.cnf
Signature ok
subject=/CN=client
Getting CA Private Key
Enter pass phrase for ca-key.pem:
[root@localhost tls]# ll
总用量 40
-rw-r--r--. 1 root root 3326 12月 3 17:20 ca-key.pem
-rw-r--r--. 1 root root 1765 12月 3 19:03 ca.pem
-rw-r--r--. 1 root root 17 12月 3 19:35 ca.srl
-rw-r--r--. 1 root root 1696 12月 3 19:35 cert.pem
-rw-r--r--. 1 root root 1582 12月 3 19:29 client.csr
-rw-r--r--. 1 root root 28 12月 3 19:32 extfile.cnf
-rw-r--r--. 1 root root 3243 12月 3 19:08 key.pem
-rw-r--r--. 1 root root 1647 12月 3 19:08 server-cert.pem
-rw-r--r--. 1 root root 1574 12月 3 19:04 server.csr
-rw-r--r--. 1 root root 3243 12月 3 19:03 server-key.pem
# 删除多余文件
[root@localhost tls]#
Prueba en el cliente
[root@client ~]# docker --tlsverify --tlscacert=ca.pem --tlscert=cert.pem --tlskey=key.pem -H tcp://master:2376 version
Client: Docker Engine - Community
Version: 19.03.13
API version: 1.40
Go version: go1.13.15
Git commit: 4484c46d9d
Built: Wed Sep 16 17:03:45 2020
OS/Arch: linux/amd64
Experimental: false
Server: Docker Engine - Community
Engine:
Version: 19.03.13
API version: 1.40 (minimum version 1.12)
Go version: go1.13.15
Git commit: 4484c46d9d
Built: Wed Sep 16 17:02:21 2020
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.3.9
GitCommit: ea765aba0d05254012b0b9e595e995c09186427f
runc:
Version: 1.0.0-rc10
GitCommit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
docker-init:
Version: 0.18.0
GitCommit: fec3683