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openssl搭建CA证书服务器

安全机制概述

信息安全防护的目标

保密性 Confidentiality
完整性 Integrity
可用性 Usability
可控制性Controlability
不可否认性 Non-repudiation

安全防护环节

物理安全：各种设备/主机、机房环境
系统安全：主机或设备的操作系统
应用安全：各种网络服务、应用程序
网络安全：对网络访问的控制、防火墙规则
数据安全：信息的备份与恢复、加密解密
管理安全：各种保障性的规范、流程、方法安全

安全攻击： STRIDE

Spoofing 假冒
Tampering 篡改
Repudiation 否认
Information Disclosure 信息泄漏
Denial of Service 拒绝服务
Elevation of Privilege 提升权限

5安全设计基本原则

使用成熟的安全系统
以小人之心度输入数据
外部系统是不安全的
最小授权
减少外部接口
缺省使用安全模式
安全不是似是而非
从STRIDE思考
在入口处检查
从管理上保护好你的系统

安全算法

常用安全技术

认证
授权
审计
安全通信

密码算法和协议：

对称加密
公钥加密
单向加密
认证协议

Linux系统：OpenSSL, gpg(pgp协议的实现)

加密需要

不加密流量的易受攻击性

密码/数据嗅探
数据操作
验证操作
相当于邮寄明信片

不安全的传统协议

telnet、FTP、POP3等等；不安全密码
http、smtp、NFS等等；不安全信息
Ldap、NIS、rsh等等；不安全验证

对称加密算法

对称加密：加密和解密使用同一个密钥

DES：Data Encryption Standard，56bits

3DES：

AES：Advanced (128, 192, 256bits)

Blowfish，Twofish

IDEA，RC6，CAST5

特性：

加密、解密使用同一个密钥，效率高
将原始数据分割成固定大小的块，逐个进行加密

缺陷：

密钥过多
密钥分发
数据来源无法确认10

非对称加密算法

公钥加密：密钥是成对出现

公钥：公开给所有人；public key

私钥：自己留存，必须保证其私密性；secret key

特点：

用公钥加密数据，只能使用与之配对的私钥解密；反之亦然

功能：

数字签名：主要在于让接收方确认发送方身份
对称密钥交换：发送方用对方的公钥加密一个对称密钥后发送给对方
数据加密：适合加密较小数据

缺点：

密钥长，加密解密效率低下

算法：

RSA（加密，数字签名）,DSA（数字签名）,ELGamal

非对称加密

基于一对公钥/密钥对

用密钥对中的一个加密，另一个解密

实现加密：

接收者

生成公钥/密钥对：P和S
公开公钥P，保密密钥S

发送者

使用接收者的公钥来加密消息M
将P(M)发送给接收者

接收者

使用密钥S来解密：M=S(P(M))

实现数字签名：

发送者

生成公钥/密钥对：P和S
公开公钥P，保密密钥S
使用密钥S来加密消息M
发送给接收者S(M)

接收者

使用发送者的公钥来解密M=P(S(M))
结合签名和加密
分离签名

CA和证书

PKI: Public Key Infrastructure

签证机构：CA（Certificate Authority）
注册机构：RA
证书吊销列表：CRL
证书存取库

X.509：定义了证书的结构以及认证协议标准

版本号
序列号
签名算法
颁发者
有效期限
主体名称
主体公钥
CRL分发点
扩展信息
发行者签名

证书获取

证书类型：

证书授权机构的证书
服务器
用户证书

获取证书两种方法：

使用证书授权机构
生成签名请求（csr）
将csr发送给CA
从CA处接收签名

自签名的证书

自已签发自己的公钥

安全协议

SSL: Secure Socket Layer

TLS: Transport Layer Security

- 1995：SSL 2.0 Netscape
- 1996: SSL 3.0
- 1999: TLS 1.0
- 2006: TLS 1.1 IETF(Internet工程任务组) RFC 4346
- 2008：TLS 1.2 当前使用
- 2015: TLS 1.3

功能：

机密性，认证，完整性，重放保护

两阶段协议，分为握手阶段和应用阶段

握手阶段(协商阶段):客户端和服务器端认证对方身份（依赖于PKI体系，利用数字证书进行身份认证），并协商通信中使用的安全参数、密码套件以及主密钥。后续通信使用的所有密钥都是通过MasterSecret生成。

应用阶段:在握手阶段完成后进入，在应用阶段通信双方使用握手阶段协商好的密钥进行安全通信

SSL/TLS

Handshake协议：包括协商安全参数和密码套件、服务器身份认证（客户端身份认证可选）、密钥交换

ChangeCipherSpec 协议：一条消息表明握手协议已经完成

Alert 协议：对握手协议中一些异常的错误提醒，分为fatal和warning两个级别，fatal类型错误会直接中断SSL链接，而warning级别的错误SSL链接仍可继续，只是会给出错误警告

Record 协议：包括对消息的分段、压缩、消息认证和完整性保护、加密等

HTTPS 协议：就是“HTTP 协议”和“SSL/TLS 协议”的组合。HTTP over SSL”或“HTTP over TLS”，对http协议的文本数据进行加密处理后，成为二进制形式传输

OpenSSL

OpenSSL：开源项目

三个组件：

openssl: 多用途的命令行工具，包openssl
libcrypto: 加密算法库，包openssl-libs
libssl：加密模块应用库，实现了ssl及tls，包nss

SSH

ssh: secure shell, protocol, 22/tcp, 安全的远程登录

具体的软件实现：

OpenSSH: ssh协议的开源实现，CentOS默认安装
dropbear：另一个开源实现

SSH协议版本

v1: 基于CRC-32做MAC，不安全；man-in-middle
v2：双方主机协议选择安全的MAC方式

基于DH算法做密钥交换，基于RSA或DSA实现身份认证

两种方式的用户登录认证：

基于password
基于key

openssl命令：

两种运行模式：交互模式和批处理模式

openssl version：程序版本号

标准命令、消息摘要命令、加密命令

标准命令：enc, ca, req, ...

对称加密：

工具：openssl enc, gpg

算法：3des, aes, blowfish, twofish

enc命令：

帮助： man enc

加密： openssl enc -e -des3 -a -salt -in testfile -out test.cipher

解密： openssl enc -d -des3 -a -salt –in test.cipher -out testfile

单向加密

工具：md5sum, sha1sum, sha224sum,sha256sum…openssl dgst

dgst命令：

帮助： man dgst

openssl dgst -md5 [-hex默认] /PATH/SOMEFILE
openssl dgst -md5 testfile
md5sum /PATH/TO/SOMEFILE

MAC: Message Authentication Code，单向加密的一种延伸应用，用于实现网络通信中保证所传输数据的完整性机制CBC-MAC

HMAC：使用md5或sha1算法31

生成用户密码

passwd命令:

帮助： man sslpasswd

openssl passwd -1 -salt SALT(最多8位)
openssl passwd -1 –salt centos

生成随机数

帮助： man sslrand

openssl rand -base64|-hex NUM

　　NUM: 表示字节数；-hex时，每个字符为十六进制，相当于4位二进制，出现的字符数为NUM*232

生成密钥对

公钥加密

　　算法：RSA, ELGamal

　　工具：gpg, openssl rsautl（man rsautl）

数字签名：

　　算法：RSA, DSA, ELGamal

密钥交换：

　　算法：dh

　　DSA: Digital Signature Algorithm

　　DSS：Digital Signature Standard

　　RSA：33

生成私钥

openssl genrsa -out /PATH/TO/PRIVATEKEY.FILE NUM_BITS
(umask 077; openssl genrsa –out test.key –des 2048)
openssl rsa -in test.key –out test2.key 将加密key解密

从私钥中提取出公钥

openssl rsa -in PRIVATEKEYFILE –pubout –out PUBLICKEYFILE
Openssl rsa –in test.key –pubout –out test.key.pub

OpenSSL证书服务器搭建

PKI：Public Key Infrastructure

CA
RA
CRL
证书存取库

证书申请及签署步骤：

生成申请请求
RA核验
CA签署
获取证书35

创建CA

openssl的配置文件： /etc/pki/tls/openssl.cnf

HOME            = .
oid_section        = new_oids
openssl_conf = default_modules
[ default_modules ]
ssl_conf = ssl_module
[ ssl_module ]
system_default = crypto_policy
[ crypto_policy ]
.include /etc/crypto-policies/back-ends/opensslcnf.config
[ new_oids ]
tsa_policy1 = 1.2.3.4.1
tsa_policy2 = 1.2.3.4.5.6
tsa_policy3 = 1.2.3.4.5.7
[ ca ]     # 语句块
default_ca    = CA_default        # The default ca section
[ CA_default ]  # 语句块
dir        = /etc/pki/CA        # ca 相关的具体路径 证书
certs        = $dir/certs        # 存放证书的目录
crl_dir        = $dir/crl        # 证书兑换列表
database    = $dir/index.txt    # 数据库 存放所有证书的信息 自动更新
                    # several certs with same subject.
new_certs_dir    = $dir/newcerts        #新证书存放的路径
certificate    = $dir/cacert.pem     # The CA certificate
serial        = $dir/serial         # 编号 存放下一个要颁发的编号
crlnumber    = $dir/crlnumber    # 吊销列表的标号
                    # must be commented out to leave a V1 CRL
crl        = $dir/crl.pem         # 证书吊销列表文件名
private_key    = $dir/private/cakey.pem# 私钥文件
x509_extensions    = usr_cert        # The extensions to add to the cert
name_opt     = ca_default        # Subject Name options
cert_opt     = ca_default        # Certificate field options
default_days    = 365            # 默认有效期
default_crl_days= 30            # 30天发布一次私钥信息
default_md    = sha256        # 默认加密算法
preserve    = no            # 
policy        = policy_match   # 策略匹配
[ policy_match ]
countryName        = match             # 必须有的信息 国家
stateOrProvinceName    = match         # 省市
organizationName    = match         # 公司
organizationalUnitName    = optional
commonName        = supplied          # 通用名 域名
emailAddress        = optional      # 
[ policy_anything ]              # 策略可以不一样
countryName        = optional
stateOrProvinceName    = optional
localityName        = optional
organizationName    = optional
organizationalUnitName    = optional
commonName        = supplied
emailAddress        = optional
[ req ]
default_bits        = 2048
default_md        = sha256
default_keyfile     = privkey.pem
distinguished_name    = req_distinguished_name
attributes        = req_attributes
x509_extensions    = v3_ca    # The extensions to add to the self signed cert
string_mask = utf8only
[ req_distinguished_name ]
countryName            = Country Name (2 letter code)
countryName_default        = XX
countryName_min            = 2
countryName_max            = 2
stateOrProvinceName        = State or Province Name (full name)
localityName            = Locality Name (eg, city)
localityName_default        = Default City
0.organizationName        = Organization Name (eg, company)
0.organizationName_default    = Default Company Ltd
organizationalUnitName        = Organizational Unit Name (eg, section)
commonName            = Common Name (eg, your name or your server's hostname)
commonName_max            = 64
emailAddress            = Email Address
emailAddress_max        = 64
[ req_attributes ]
challengePassword        = A challenge password
challengePassword_min        = 4
challengePassword_max        = 20
unstructuredName        = An optional company name
[ usr_cert ]
basicConstraints=CA:FALSE
nsComment            = "OpenSSL Generated Certificate"
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer
[ v3_req ]
basicConstraints = CA:FALSE
keyUsage = nonRepudiation, digitalSignature, keyEncipherment
[ v3_ca ]
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid:always,issuer
basicConstraints = critical,CA:true
[ crl_ext ]
authorityKeyIdentifier=keyid:always
[ proxy_cert_ext ]
basicConstraints=CA:FALSE
nsComment            = "OpenSSL Generated Certificate"
subjectKeyIdentifier=hash
authorityKeyIdentifier=keyid,issuer
proxyCertInfo=critical,language:id-ppl-anyLanguage,pathlen:3,policy:foo
[ tsa ]
default_tsa = tsa_config1    # the default TSA section
[ tsa_config1 ]
dir        = /etc/pki/CA        # TSA root directory
serial        = $dir/tsaserial    # The current serial number (mandatory)
crypto_device    = builtin        # OpenSSL engine to use for signing
signer_cert    = $dir/tsacert.pem     # The TSA signing certificate
                    # (optional)
certs        = $dir/cacert.pem    # Certificate chain to include in reply
                    # (optional)
signer_key    = $dir/private/tsakey.pem # The TSA private key (optional)
signer_digest  = sha256            # Signing digest to use. (Optional)
default_policy    = tsa_policy1        # Policy if request did not specify it
                    # (optional)
other_policies    = tsa_policy2, tsa_policy3    # acceptable policies (optional)
digests     = sha1, sha256, sha384, sha512  # Acceptable message digests (mandatory)
accuracy    = secs:1, millisecs:500, microsecs:100    # (optional)
clock_precision_digits  = 0    # number of digits after dot. (optional)
ordering        = yes    # Is ordering defined for timestamps?
                # (optional, default: no)
tsa_name        = yes    # Must the TSA name be included in the reply?
                # (optional, default: no)
ess_cert_id_chain    = no    # Must the ESS cert id chain be included?
                # (optional, default: no)
ess_cert_id_alg        = sha1    # algorithm to compute certificate
                # identifier (optional, default: sha1)

主配置文件(不需要修改)

创建所需要的文件

mkdir /etc/pki/CA/
mkdir /etc/pki/CA/{certs,crl,newcerts,private}
[root@djcy-200 CA]# tree 
.
├── certs
├── crl
├── newcerts
└── private

mkdir /etc/pki/CA/crlnumber
touch /etc/pki/CA/index.txt 生成证书索引数据库文件
echo 01 > /etc/pki/CA/serial 指定第一个颁发证书的序列号

CA生成私钥

# 输入密码 每次签发证书都需认证
[root@djcy-200 CA]# (umask 066; openssl genrsa -out private/cakey.pem -des3 2048)
Generating RSA private key, 2048 bit long modulus (2 primes)
...................................+++++
..................................+++++
e is 65537 (0x010001)
Enter pass phrase for private/cakey.pem:
Verifying - Enter pass phrase for private/cakey.pem:
[root@djcy-200 CA]# tree 
.
├── certs
├── crl
├── newcerts
└── private
    └── cakey.pem

CA自签证书

参数说明:
    -new: 生成新证书签署请求
    -x509: 专用于CA生成自签证书
    -key: 生成请求时用到的私钥文件
    -days n：证书的有效期限
    -out /PATH/TO/SOMECERTFILE: 证书的保存路径
[root@djcy-200 CA]# openssl req -new -x509 -key private/cakey.pem -days 18250 -out /etc/pki/CA/cacert.pem
Enter pass phrase for private/cakey.pem:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [XX]:CN
State or Province Name (full name) []:BeiJing      
Locality Name (eg, city) [Default City]:BeiJing
Organization Name (eg, company) [Default Company Ltd]:devops
Organizational Unit Name (eg, section) []:ops
Common Name (eg, your name or your server's hostname) []:ca.devops.com
Email Address []:admin@devops.com
[root@djcy-200 CA]# tree 
.
├── cacert.pem
├── certs
├── crl
├── newcerts
└── private
    └── cakey.pem

4 directories, 2 files查看

查看证书信息

[root@djcy-200 CA]# openssl x509 -in cacert.pem -noout -text
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            11:10:a5:ca:51:77:cb:43:06:61:42:27:9d:ec:5e:35:d7:9b:61:17
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = CN, ST = BeiJing, L = BeiJing, O = devops, OU = ops, CN = ca.devops.com, emailAddress = admin@devops.com
        Validity
            Not Before: Aug  2 13:34:53 2020 GMT
            Not After : Jul 21 13:34:53 2070 GMT
        Subject: C = CN, ST = BeiJing, L = BeiJing, O = devops, OU = ops, CN = ca.devops.com, emailAddress = admin@devops.com
  ''''''''  省略

# 只查看某些内容
[root@djcy-200 CA]# openssl x509 -in cacert.pem -noout -dates 
notBefore=Aug  2 13:34:53 2020 GMT
notAfter=Jul 21 13:34:53 2070 GMT

客户端请求颁发证书

生成私钥

[root@djcy-62 ~]# mkdir ca
[root@djcy-62 ~]# cd ca/
[root@djcy-62 ca]# (umask 066;openssl genrsa -out app.key 1024)
Generating RSA private key, 1024 bit long modulus (2 primes)
............+++++
......................+++++
e is 65537 (0x010001)
[root@djcy-62 ca]# ll
total 4
-rw------- 1 root root 891 Aug  2 21:43 app.key

使用私钥生成请求

[root@djcy-62 ca]# openssl req -new -key app.key -out app.csr
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [XX]:CN						# 必须跟CA服务器一致
State or Province Name (full name) []:BeiJing               # 必须跟CA服务器一致
Locality Name (eg, city) [Default City]:ChaoYang
Organization Name (eg, company) [Default Company Ltd]:devops # 必须跟CA服务器一致
Organizational Unit Name (eg, section) []:webdev    
Common Name (eg, your name or your server's hostname) []:www.devops.com  # 颁发的域名
Email Address []:dev@devops.com

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
[root@djcy-62 ca]# ll
total 8
-rw-r--r-- 1 root root 700 Aug  2 21:47 app.csr
-rw------- 1 root root 891 Aug  2 21:43 app.key

发送请求秘钥到CA服务器

[root@djcy-62 ca]# scp app.csr bjcy-200.host.io:/etc/pki/CA/

查看服务器颁发的密码

[root@djcy-62 ca]# openssl x509 -in app.crt -noout -text
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number: 1 (0x1)
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = CN, ST = BeiJing, L = BeiJing, O = devops, OU = ops, CN = ca.devops.com, emailAddress = admin@devops.com
        Validity
            Not Before: Aug  2 14:01:05 2020 GMT
            Not After : Jul 31 14:01:05 2030 GMT
        Subject: C = CN, ST = BeiJing, O = devops, OU = webdev, CN = www.devops.com, emailAddress = dev@devops.com
        Subject Public Key Info:
''''''' 省略'

CA授权客户端

[root@djcy-200 CA]# touch index.txt							# 数据库文件存放着所有的申请授权信息
[root@djcy-200 CA]# echo 01 > /etc/pki/CA/serial            # 开始申请的编号 每次都会增加
[root@djcy-200 CA]# openssl ca -in app.csr -out certs/app.crt -days 3650   # 开始授权
Using configuration from /etc/pki/tls/openssl.cnf
Enter pass phrase for /etc/pki/CA/private/cakey.pem:
Check that the request matches the signature
Signature ok
Certificate Details:
        Serial Number: 1 (0x1)
        Validity
            Not Before: Aug  2 14:01:05 2020 GMT
            Not After : Jul 31 14:01:05 2030 GMT
        Subject:
            countryName               = CN
            stateOrProvinceName       = BeiJing
            organizationName          = devops
            organizationalUnitName    = webdev
            commonName                = www.devops.com
            emailAddress              = dev@devops.com
        X509v3 extensions:
            X509v3 Basic Constraints: 
                CA:FALSE
            Netscape Comment: 
                OpenSSL Generated Certificate
            X509v3 Subject Key Identifier: 
                BF:F7:D0:7A:0B:B8:11:6E:27:64:69:C2:7D:3D:38:62:69:E7:4A:10
            X509v3 Authority Key Identifier: 
                keyid:31:BC:8B:B0:A6:F8:FF:B7:6E:F9:B2:E5:7C:80:B8:47:6C:AA:AB:1D

Certificate is to be certified until Jul 31 14:01:05 2030 GMT (3650 days)
Sign the certificate? [y/n]:y								# 是否授权


1 out of 1 certificate requests certified, commit? [y/n]y		# 确认
Write out database with 1 new entries
Data Base Updated
[root@djcy-200 CA]# tree 
.
├── app.csr
├── cacert.pem
├── certs
│   └── app.crt			# 生产的私钥文件
├── crl
├── index.txt
├── index.txt.attr
├── index.txt.old
├── newcerts
│   └── 01.pem       # 和 certs下的 app.crt 是同一个文件
├── private
│   └── cakey.pem
├── serial
└── serial.old

4 directories, 10 files
[root@djcy-200 CA]# cat index.txt    # 数据库文件
V	300731140105Z		01	unknown	/C=CN/ST=BeiJing/O=devops/OU=webdev/CN=www.devops.com/emailAddress=dev@devops.com
[root@djcy-200 CA]# cat serial     # 下次申请的编号
02

CA吊销证书

[root@djcy-200 CA]# echo 01 > /etc/pki/CA/crlnumber

[root@djcy-200 CA]# openssl ca -revoke newcerts/01.pem   指定吊销证书
Using configuration from /etc/pki/tls/openssl.cnf
Enter pass phrase for /etc/pki/CA/private/cakey.pem:
Revoking Certificate 01.
Data Base Updated
[root@djcy-200 CA]# tree 
.
├── app.csr
├── cacert.pem
├── certs
│   └── app.crt
├── crl
├── crlnumber
├── index.txt
├── index.txt.attr
├── index.txt.attr.old
├── index.txt.old
├── newcerts
│   └── 01.pem
├── private
│   └── cakey.pem
├── serial
└── serial.old

4 directories, 12 files
[root@djcy-200 CA]# openssl ca -gencrl -out crl.pem # 生成证书吊销列表
Using configuration from /etc/pki/tls/openssl.cnf
Enter pass phrase for /etc/pki/CA/private/cakey.pem:
[root@djcy-200 CA]# tree 
.
├── app.csr
├── cacert.pem
├── certs
│   └── app.crt
├── crl
├── crlnumber
├── crlnumber.old
├── crl.pem
├── index.txt
├── index.txt.attr
├── index.txt.attr.old
├── index.txt.old
├── newcerts
│   └── 01.pem
├── private
│   └── cakey.pem
├── serial
└── serial.old

4 directories, 14 files
[root@djcy-200 CA]# # 查看吊销列表文件
[root@djcy-200 CA]# openssl crl -in crl
crl/           crlnumber      crlnumber.old  crl.pem        
[root@djcy-200 CA]# openssl crl -in crl.pem -noout -text 
Certificate Revocation List (CRL):
        Version 2 (0x1)
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = CN, ST = BeiJing, L = BeiJing, O = devops, OU = ops, CN = ca.devops.com, emailAddress = admin@devops.com
        Last Update: Aug  2 14:21:56 2020 GMT
        Next Update: Sep  1 14:21:56 2020 GMT
        CRL extensions:
            X509v3 CRL Number: 
                1
Revoked Certificates:
    Serial Number: 01
        Revocation Date: Aug  2 14:20:37 2020 GMT
    Signature Algorithm: sha256WithRSAEncryption
         29:af:64:35:f5:aa:48:dd:7b:9d:0e:2c:a0:73:95:a1:e3:9a:
         fc:16:a9:e0:51:7d:a8:ee:f1:c4:f1:83:f9:b3:88:f2:f5:12:
         06:27:f7:f0:92:19:91:7b:f6:bc:30:ed:c6:34:ed:26:2d:ae:
         a7:2b:a2:7f:c2:60:9b:e1:24:2d:23:34:7b:7c:5e:ee:66:07:
         da:2f:c5:8e:35:e8:65:aa:89:da:d7:1f:df:53:9b:c6:4a:78:
         a8:09:fe:f3:0d:f4:0d:d6:65:48:0b:3d:75:73:19:26:db:ba:
         d0:0d:74:0c:c2:89:30:e5:33:f4:db:fd:73:e8:1e:07:30:1c:
         05:03:47:df:b3:82:26:e7:73:64:14:07:b9:f3:70:eb:8d:c0:
         fb:74:07:d8:22:ad:ce:3c:2e:ad:4a:00:cb:6c:9e:60:6c:dd:
         8c:14:ea:95:69:4a:be:ab:57:25:2d:ed:54:5a:45:04:13:4c:
         3a:90:23:96:d8:1b:01:c3:c6:a3:55:cf:8e:8b:c7:85:08:9b:
         44:ab:e8:eb:0f:c5:7c:8d:05:ef:d8:db:45:2c:36:32:f9:0c:
         56:db:6b:aa:72:1d:68:a8:4c:3f:7a:58:fc:26:cf:0c:53:d1:
         d2:57:33:4a:22:44:89:49:74:7a:1b:4f:91:0d:0f:59:5d:b0:
         83:28:66:02

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原文地址：https://www.cnblogs.com/yanshicheng/p/13424198.html