使用openssl实现私有CA的搭建和证书的颁发

[root@CentOS8 tls]#  vim /etc/pki/tls/openssl.cnf
[ ca ]
default_ca      = CA_default            # 默认使用的CA

####################################################################
[ CA_default ]
dir             = /etc/pki/CA           # 存放和CA相关的文件的目录（CentOS7这个文件默认存在）
certs           = $dir/certs            # 存放颁发的证书  Cert：证书
crl_dir         = $dir/crl              # 存放被吊销的证书
database        = $dir/index.txt        # 存放ca的索引（需要人为创建）
new_certs_dir   = $dir/newcerts         # 存放新证书的位置
certificate     = $dir/cacert.pem       # ca的自签名证书
serial          = $dir/serial           # 证书的编号（第一次需要人为创建并编号，后面会自动递增） serial：连续的
crlnumber       = $dir/crlnumber        # 证书吊销列表的编号
crl             = $dir/crl.pem          # 证书吊销列表的文件
private_key     = $dir/private/cakey.pem# CA的私钥
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

policy          = policy_match  #指定使用的匹配策略

# For the CA policy
[ policy_match ]
countryName             = match
stateOrProvinceName     = match
organizationName        = match
organizationalUnitName  = optional
commonName              = supplied
emailAddress            = optional

[root@CentOS8 CA]# mkdir -pv /etc/pki/CA/{certs,crl,newcerts,private}
mkdir: created directory '/etc/pki/CA/certs' #存放颁发的证书文件
mkdir: created directory '/etc/pki/CA/crl'  #存放吊销的证书文件
mkdir: created directory '/etc/pki/CA/newcerts' #存放新生成的证书文件
mkdir: created directory '/etc/pki/CA/private'  #存放CA自己的私钥

#证书的数据库文件：存放证书的颁发等信息，不需要人工维护里面的内容，只需要创建对应的文件就行了，会自动往里面写入数据的
[root@centos8 ~]# touch /etc/pki/CA/index.txt

#颁发证书的序号（十六进制）：第一个证书颁发的时候使用的就是这个编号，后续会自动递增
[root@centos8 ~]# echo 01 > /etc/pki/CA/serial

[root@CentOS8 CA]# openssl genrsa -out private/cakey.pem 2048
Generating RSA private key, 2048 bit long modulus (2 primes)
..........................+++++
........................................................................+++++
e is 65537 (0x010001)

[root@CentOS8 CA]# openssl req -new -x509 -key /etc/pki/CA/private/cakey.pem -days 3650 -out /etc/pki/CA/cacert.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) []:SC
Locality Name (eg, city) [Default City]:CD
Organization Name (eg, company) [Default Company Ltd]:SX
Organizational Unit Name (eg, section) []:LL
Common Name (eg, your name or your server's hostname) []:tom
Email Address []:111

选项:
-new：创建一个新的证书，生成新证书签署请求

-x509：表示证书的格式，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

查看自签名证书的信息
[root@centos8 ~]#openssl x509 -in /etc/pki/CA/cacert.pem -noout -text

-in:指定输入的文件

-noout：不输出为文件

-text：以文本方式来进行显示

[root@CentOS8 CA]# mkdir /data/app1

[root@CentOS8 app1]# openssl genrsa -out /data/app1/app1.key 2048
Generating RSA private key, 2048 bit long modulus (2 primes)
.................................+++++
...............................................................................................+++++
e is 65537 (0x010001)

[root@CentOS8 app1]# openssl req -new -key /data/app1/app1.key -out /data/app1/app1.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  #国家
State or Province Name (full name) []:CN #省份
Locality Name (eg, city) [Default City]:CN #组织
Organization Name (eg, company) [Default Company Ltd]:CN
Organizational Unit Name (eg, section) []:CN
Common Name (eg, your name or your server's hostname) []:CN
Email Address []:CN

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

[root@CentOS8 app1]# openssl ca -in /data/app1/app1.csr  -out /etc/pki/CA/certs/app1.crt -days 1000
Using configuration from /etc/pki/tls/openssl.cnf
Check that the request matches the signature
Signature ok
Certificate Details:
        Serial Number: 15 (0xf)
        Validity
            Not Before: Oct 14 06:53:07 2022 GMT
            Not After : Jul 10 06:53:07 2025 GMT
        Subject:
            countryName               = CN
            stateOrProvinceName       = CN
            organizationName          = CN
            organizationalUnitName    = CN
            commonName                = CN
            emailAddress              = CN
        X509v3 extensions:
            X509v3 Basic Constraints: 
                CA:FALSE
            Netscape Comment: 
                OpenSSL Generated Certificate
            X509v3 Subject Key Identifier: 
                12:C5:3F:8E:86:E4:E8:3C:06:B1:01:79:90:EA:B6:66:32:53:3E:6A
            X509v3 Authority Key Identifier: 
                keyid:10:59:CD:C9:34:58:5E:30:67:43:0A:3E:DD:7C:63:2B:9C:60:50:3A

Certificate is to be certified until Jul 10 06:53:07 2025 GMT (1000 days)
Sign the certificate? [y/n]:y
1 out of 1 certificate requests certified, commit? [y/n]y
Write out database with 1 new entries
Data Base Updated

[root@CentOS8 CA]# tree
.
├── cacert.pem
├── certs
│   └── app1.crt #给用户生成的生成的证书文件
├── crl
├── index.txt
├── index.txt.attr
├── index.txt.old  #前一个文件的备份
├── newcerts
│   └── 0F.pem #和app1.crt是同一个东西，自动生成的一个备份文件
├── private
│   └── cakey.pem
├── serial
└── serial.old

4 directories, 9 files

#serial：存放的是下一个证书的证书编号

[root@CentOS8 CA]# openssl ca -status 0F  #0F就是这个证书的标号
Using configuration from /etc/pki/tls/openssl.cnf
0F=Valid (V)

V：标识生效的   R：标识无效的证书

openssl x509 -in /etc/pki/CA/certs/app1.crt -noout -text

[root@CentOS8 CA]# openssl x509 -in /etc/pki/CA/certs/app1.crt -noout -issuer
issuer=C = CN, ST = CN, L = CN, O = CN, OU = CN, CN = CN, emailAddress = CN

后缀规定：
.crt #证书文件的标识

.csr #证书申请文件的标识  证书申请完成后，这个证书申请文件就没啥用了

.key #私钥的标识  .pem也是私钥的标识，但是windows不是别pem结尾的文件

root@CentOS8 CA]# pwd
/etc/pki/CA
[root@CentOS8 CA]# cat index.txt.attr 
unique_subject = yes


unique_subject = yes  #把yes变为no就可以了

openssl ca -revoke /PATH/FILE

[root@CentOS8 CA]# openssl ca -revoke certs/app1.crt
Using configuration from /etc/pki/tls/openssl.cnf
Revoking Certificate 0F.
Data Base Updated

[root@CentOS8 CA]# openssl ca -status 0F 
Using configuration from /etc/pki/tls/openssl.cnf
0F=Revoked (R)

[root@CentOS8 CA]# cat /etc/pki/CA/index.txt
R	250710065307Z	221014072459Z	0F	unknown	/C=CN/ST=CN/O=CN/OU=CN/CN=CN/emailAddress=CN

#需要创建一个clinumer文件才可以  吊销证书也需要一个吊销证书的number 类似于index.txt

#这个文件默认不存在，需要手动创建出来

echo 01 > /etc/pki/CA/crlnumber

openssl ca -gencrl -out /etc/pki/CA/crl.pem   #证书吊销文件的路径是约定好的