Openssl: How to automate (without hitting the carriage return many times)

I think nearly everyone, who administers some PCs or servers has used openssl. And almost everything there is straight forward.

To create your own key and certificate, just run:

openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 \
 -keyout privateKey.key -out certificate.crt

 

............+..+.+.................+............+.+......+........+.+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*.+....................+......+.+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*.......+.+.....+...+..........+...............+....................+.+...+..+..........+........+......+.+...+.....+...+.......+..+.+...+...........+....+..+.......+.....+...............+................+......+......+...+......+...+...+..+......+......+.........+....+........+............+..........+.....+...+.......+..+...+.............+...+......+..............+....+...........+....+..+.+..+...+.............+............+...+..+.........+...+...............+...+..........+.........+...+...+...+...............+.........+..+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
..........+.....+.......+.........+..+.............+.....+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*.......+.............+.........+..+....+..+...+.+......+...+.....+.........+.+.....+.+.....+...+.+.....+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*..+......+............................+.....+....+..+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
-----
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]:
State or Province Name (full name) [Some-State]:
Locality Name (eg, city) []:
Organization Name (eg, company) [Internet Widgits Pty Ltd]:
Organizational Unit Name (eg, section) []:
Common Name (e.g. server FQDN or YOUR name) []:
Email Address []:

But the problem with that approach:

You have to add the carriage returns for every line after the 5 dashes and then your certificate looks quite ugly (see red colored text):

openssl x509 -text -in certificate.crt -noout

 

Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            0b:01:9a:aa:f1:59:69:33:84:7e:cf:89:69:0c:d5:80:61:82:b5:28
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd
        Validity
            Not Before: Jan 22 15:54:43 2023 GMT
            Not After : Jan 22 15:54:43 2024 GMT
        Subject: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
                Public-Key: (2048 bit)
                Modulus:
                    00:c6:7d:5a:9f:97:3d:43:9b:e0:19:2f:46:31:5c:
                    82:f0:42:ac:da:a9:e8:d0:91:e0:01:98:05:52:cf:
                    1c:4e:77:53:1a:96:5c:6a:6f:ca:5c:61:a4:5f:14:
                    12:ed:69:ae:50:bb:99:28:48:df:bc:f6:76:c1:63:
                    2b:51:55:ad:bb:62:9f:3a:2b:1f:e7:c3:fd:bb:45:
                    04:c3:88:ee:b1:ba:c6:e2:f7:f1:80:5b:ef:eb:04:
                    fb:ec:82:89:39:c6:33:68:0d:3e:36:62:36:e0:a0:
                    ff:21:5f:74:ad:d2:4b:d4:5d:c4:67:6b:90:a0:8f:
                    1e:4c:80:31:30:2e:8e:5e:9d:62:8a:1d:45:84:5f:
                    d3:09:46:fe:4f:8d:68:c6:54:e4:51:da:e0:64:f8:
                    5d:af:01:2e:79:0c:fe:0b:0f:d6:2e:1b:e6:eb:09:
                    ca:cc:16:3d:92:53:ae:3b:ad:da:67:a5:ef:69:30:
                    7f:e7:53:7c:dd:23:59:c8:8c:6b:b0:a9:fa:fc:4c:
                    c1:44:cf:3f:2f:91:f4:8c:b6:7c:d9:ae:82:6d:96:
                    aa:bb:51:07:3c:2b:12:24:e4:a3:7d:9b:ee:4b:7e:
                    f4:02:0e:bc:b4:35:bd:73:dc:6b:b4:34:36:57:48:
                    72:f2:91:60:2d:79:d9:44:3c:77:76:eb:c7:8a:00:
                    5f:75
                Exponent: 65537 (0x10001)
        X509v3 extensions:
            X509v3 Subject Key Identifier: 
                F1:77:6C:19:76:FB:E4:DD:50:2A:1E:01:BE:A1:5C:48:3D:5A:40:68
            X509v3 Authority Key Identifier: 
                F1:77:6C:19:76:FB:E4:DD:50:2A:1E:01:BE:A1:5C:48:3D:5A:40:68
            X509v3 Basic Constraints: critical
                CA:TRUE
    Signature Algorithm: sha256WithRSAEncryption
    Signature Value:
        8a:28:28:12:6c:1e:e5:54:86:9b:6e:90:7a:ca:aa:a7:a1:b3:
        b1:43:02:44:e8:9a:59:b2:d6:6e:36:c6:51:3b:9b:f4:91:47:
        40:6f:cf:6d:de:86:8d:dd:2f:9e:44:4c:f8:d3:5a:d3:3a:ef:
        d5:0d:e1:10:b6:64:34:ee:03:4a:f2:de:ff:da:db:a3:93:20:
        13:85:2a:d6:9b:b2:0e:2c:2e:9c:f9:71:ff:32:3b:c3:6b:0a:
        e7:98:2d:30:c9:a6:47:b7:72:84:bb:52:23:11:d6:b7:90:cb:
        98:cd:59:16:b5:8f:70:46:c1:95:90:01:2f:7f:9c:22:ac:29:
        8d:14:97:76:dd:06:56:f8:22:9d:f4:00:9f:40:3c:fb:c2:95:
        63:48:50:ee:ad:17:1b:54:6b:60:0c:d5:3e:66:3b:00:0e:7a:
        33:99:cc:4a:f6:dc:d1:e3:40:ea:8c:66:df:7e:92:e1:a5:e5:
        72:0e:89:ba:87:43:0c:56:70:8c:f2:9b:77:dd:ca:03:8e:24:
        fd:6b:51:d2:3b:b2:df:e4:ff:c2:3c:cb:ab:2e:cd:82:f4:69:
        ad:a3:81:d7:95:d0:68:e1:3f:fc:50:4d:8b:14:b2:82:8c:19:
        2b:06:8a:0e:ef:21:4b:68:4f:e3:1d:53:64:62:97:c8:35:45:
        01:54:d9:10

To avoid that you have just to expand your command with the following parameters:

openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 \
 -keyout privateKey.key -out certificate.crt \
 -subj "/C=de/CN=schroff.special/OU=MyDepartment" 

Typical attributes can be found here:

(Common Name, Organization, Organizational Unit, Country, Location)