전제 조건

루트 CA 인증서 생성

   $ openssl genrsa -out rootCAkey.pem 4096
   Generating RSA private key, 4096 bit long modulus (2 primes)
   .........................................++++
   .........++++
   e is 65537 (0x010001)

We generate random keys with 4,096 character and you can use other lengths like 1024, 2048, 8192, or ETC. You can increase or decrease your key length to optimize cpu power to process them.

   $ openssl req -x509 -sha256 -new -nodes -key rootCAkey.pem \
      -days 14 -out rootCAcert.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) [AU]:TH
   State or Province Name (full name) [Some-State]:Bangkok
   Locality Name (eg, city) []:BangKhea
   Organization Name (eg, company) [Internet Widgits Pty Ltd]:Opsta Thailand
   Organizational Unit Name (eg, section) []:DevOps
   Common Name (e.g. server FQDN or YOUR name) []:OpstaRootCA
   Email Address []:[email protected]

For the previous command, I request a new certificate file with some information. I use the digest algorithm SHA-256 and set it to expire before 14 days. It shows a prompt on your terminal for adding more information. You can see an example above.

   openssl x509 -text -in rootCAcert.pem

You can see your certificate information. Then go to the next step to create a chain certificate.

발급자로 서버 인증서 생성

   # You can replace rsaServerKey.pem to your name
   # And can change key size from 2048 to other length
   $ openssl genrsa -out rsaServerKey.pem 2048
   Generating RSA private key, 2048 bit long modulus (2 primes)
   ......................................................................+++++
   ...............+++++
   e is 65537 (0x010001)

   # req.cnf
   [req]
   req_extensions = v3_req
   distinguished_name = dn
   prompt = no

   [dn]
   CN = ssl-lab.example.local
   C = TH
   L = Bangkok
   O = Opsta Thailand
   OU = DevOps

   [v3_req]
   subjectAltName = @san_names

   [san_names]
   DNS.1 = ssl-lab.example.local
   DNS.2 = localhost
   DNS.3 = 127.0.0.1

Provide simple configuration to create CSR file. This file has SAN(Subject Alternative Name) with 3 names in [san_names]. For @san_names, I use for extend alternative name for server.

   $ openssl req -new -out req.csr -key rsaServerKey.pem -sha256 -config req.cnf
   $ cat req.csr
   -----BEGIN CERTIFICATE REQUEST-----
   MIIC9zCCAd8CAQAwaTEeMBwGA1UEAwwVc3NsLWxhYi5leGFtcGxlLmxvY2FsMQsw
   CQYDVQQGEwJUSDEQMA4GA1UEBwwHQmFuZ2tvazEXMBUGA1UECgwOT3BzdGEgVGhh
   aWxhbmQxDzANBgNVBAsMBkRldk9wczCCASIwDQYJKoZIhvcNAQEBBQADggEPADCC
   …
   k9jkEKhPeICqJgHLbyiEcEc9xaPTMPb35cBQT8irnUq1+WbQamhWDIBmwzDHCSyf
   jCK672ACRleQCj8kk5l+dOB0wzWEaDcCoQNwIwqg2RpfDKc1lHARroBzm1P/4grg
   NaF5EYJJWhXUXGKq68meHpCTGzgC7M06rwBdOR+8l0GIUZ5K25MvNg3+ZA==
   -----END CERTIFICATE REQUEST-----

   $ openssl req -in req.csr -noout -text
   …
   Requested Extensions:
               X509v3 Subject Alternative Name: 
                   DNS:ssl-lab.example.local, DNS:localhost, DNS:127.0.0.1

   $ openssl x509 -req -sha256 -in req.csr -CA ../rootCAcert.pem \
     -extfile <(printf "subjectAltName=DNS:ssl-lab.example.local,DNS:localhost") \
     -CAkey ../rootCAkey.pem -CAcreateserial -out CertServer.pem -days 7
   …
   Signature ok
   subject=CN = ssl-lab.example.local, C = TH, L = Bangkok, O = Opsta Thailand, OU = DevOps
   Getting CA Private Key

We create trusted certificates with digest algorithm SHA-256 and create root CA serials that track how many certificates were issued with -CAcreateserial , so if not the first certificate you will use -CAserial instead. Then, this certificate will stay for 7 days only.

   $ openssl x509 -text -in CertServer.pem
   …
   Issuer: C = TH, ST = Bangkok, L = BangKhea, O = Opsta Thailand, OU = DevOps, CN = OpstaRootCA, emailAddress = [email protected]

We will see Issuer information under Certificate >> Data.

데모 웹 서버 실행

데모 웹 서버 실행

FROM nginx:1.20-alpine

ADD default.conf /etc/nginx/conf.d/default.conf

COPY ssl /etc/nginx/ssl

RUN chown -R 0:0 /etc/nginx/ssl \
    && chown -R 0:0 /etc/nginx/conf.d/default.conf

server {
    listen       80;
    server_name  localhost ssl-lab.example.local;
    return 301 https://localhost:8443$request_uri;
}
server {
    listen              443 ssl;
    server_name         localhost ssl-lab.example.local;
    keepalive_timeout   70;
    ssl_certificate     /etc/nginx/ssl/CertServer.pem;
    ssl_certificate_key /etc/nginx/ssl/rsaServerKey.pem;
    ssl_protocols       TLSv1.1 TLSv1.2;
    ssl_prefer_server_ciphers off;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}

docker build -t nginx-ca:demo .
docker run -it --rm -p 8080:80 -p 8443:443 nginx-ca:demo

$ curl -vIL --cacert ../rootCA/rootCAcert.pem -XGET https://localhost:8443

*   Trying 127.0.0.1:8443...
* Connected to localhost (127.0.0.1) port 8443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
*  CAfile: rootCA/rootCAcert.pem
*  CApath: /etc/ssl/certs
* TLSv1.0 (OUT), TLS header, Certificate Status (22):
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS header, Finished (20):
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS header, Finished (20):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384
* ALPN, server accepted to use http/1.1
* Server certificate:
*  subject: CN=ssl-lab.example.local; C=TH; L=Bangkok; O=Opsta Thailand; OU=DevOps
*  start date: Sep 16 06:36:23 2022 GMT
*  expire date: Oct 16 06:36:23 2022 GMT
*  subjectAltName: host "localhost" matched cert's "localhost"
*  issuer: C=TH; ST=Bangkok; O=Opsta Thailand; OU=DevOps; CN=OpstaRootCA; [email protected]
*  SSL certificate verify ok.
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
> GET / HTTP/1.1
> Host: localhost:8443
> User-Agent: curl/7.81.0
> Accept: */*
> 
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
HTTP/1.1 200 OK
< Server: nginx/1.20.2
Server: nginx/1.20.2
< Date: Mon, 19 Sep 2022 02:57:09 GMT
Date: Mon, 19 Sep 2022 02:57:09 GMT
< Content-Type: text/html
Content-Type: text/html
< Content-Length: 612
Content-Length: 612
< Last-Modified: Tue, 16 Nov 2021 15:04:23 GMT
Last-Modified: Tue, 16 Nov 2021 15:04:23 GMT
< Connection: keep-alive
Connection: keep-alive
< ETag: "6193c877-264"
ETag: "6193c877-264"
< Accept-Ranges: bytes
Accept-Ranges: bytes

< 
* Excess found: excess = 612 url = / (zero-length body)
* Connection #0 to host localhost left intact