今天也来点Docker，Docker-TLS加密通讯

一、TLS加密通讯的概述

• 用TLS加密通讯原因：
  为了防止链路劫持、会话劫持等问题导致 Docker 通信时被中 间人攻击，c/s 两端应该通过加密方式通讯。
• 对称密钥，例如DES、3DES、AES，长度不同，长度越长安全越高，解密速度越慢。
• 非对称密钥，分为公钥和私钥，例如RSA 公钥：所有人可知（锁），私钥（钥匙）个人身份信息，不可抵赖。
• 封装在证书中：个人信息，密钥，有效期

二、TLS加密通讯的部署

2.1、搭建环境

2.2 部署过程

• Server

[root@cgroup ~]# hostnamectl set-hostname master
[root@cgroup ~]# bash
[root@master ~]#systemctl stop firewalld
[root@master ~]# setenforce 0

[root@master ~]# mkdir /tls
[root@master ~]# cd /tls

[root@master tls]# vim /etc/hosts
127.0.0.1   master

#创建ca密钥，输入密码123123
[root@master 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，输入密码123123
[root@master tls]# openssl req -new -x509 -days 1000 -key ca-key.pem -sha256 -subj "/CN=*" -out ca.pem
Enter pass phrase for ca-key.pem:

#创建服务器私钥
[root@master tls]# openssl genrsa -out server-key.pem 4096
Generating RSA private key, 4096 bit long modulus
.........................................++
......................................++
e is 65537 (0x10001)

#签名私钥
[root@master tls]# openssl req -subj "/CN=*" -sha256 -new -key server-key.pem -out server.csr

#使用ca证书与私钥证书签名，输入密码123123
[root@master 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@master tls]# openssl genrsa -out key.pem 4096
Generating RSA private key, 4096 bit long modulus
........................................................................................................................................................................................................++
..++
e is 65537 (0x10001)

#签名客户端
[root@master tls]# openssl req -subj "/CN=client" -new -key key.pem -out client.csr

#创建配置文件
[root@master tls]# echo extendedKeyUsage=clientAuth > extfile.cnf

#签名证书，输入密码123123
[root@master 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:

#删除多余文件
[root@master tls]# rm -rf ca.srl client.csr extfile.cnf server.csr

#查看生成文件
[root@master tls]# ls
ca-key.pem  ca.pem  cert.pem  key.pem  server-cert.pem  server-key.pem

• 配置docker
  vim /lib/systemd/system/docker.service
  

• 重启进程
  systemctl daemon-reload

• 重启docker服务
  systemctl restart docker

• 将 /tls/ca.pem /tls/cert.pem /tls/key.pem 三个文件复制到另一台主机

[root@master tls]# scp ca.pem root@20.0.0.60:/etc/docker/
The authenticity of host '20.0.0.60 (20.0.0.60)' can't be established.
ECDSA key fingerprint is SHA256:N36uwPtXA/RHGdEsLwiaV6x0pMPitNj+MSO3APPZtC4.
ECDSA key fingerprint is MD5:14:cf:b4:13:36:a1:ea:c6:dc:01:f5:83:65:ca:b0:39.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '20.0.0.60' (ECDSA) to the list of known hosts.
root@20.0.0.60's password: 
ca.pem                                                                100% 1765     2.6MB/s   00:00    
[root@master tls]# scp cert.pem root@20.0.0.60:/etc/docker/
root@20.0.0.60's password: 
cert.pem                                                              100% 1696     1.3MB/s   00:00    
[root@master tls]# scp key.pem root@20.0.0.60:/etc/docker/
root@20.0.0.60's password: 
key.pem                                                               100% 3247     1.3MB/s   00:00    

2.3 验证加密通讯

• Server上验证

[root@master tls]# 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:          1.3.7
  GitCommit:        8fba4e9a7d01810a393d5d25a3621dc101981175
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

• Client上验证

[root@client ~]# vim /etc/hosts
20.0.0.50 master

[root@client ~]# cd /etc/docker/
[root@client docker]# 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:          1.3.7
  GitCommit:        8fba4e9a7d01810a393d5d25a3621dc101981175
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683