Skip to content

Instantly share code, notes, and snippets.

@yidas
Last active May 22, 2024 12:11
Show Gist options
  • Save yidas/af42d2952d85c0951c1722fcd68716c6 to your computer and use it in GitHub Desktop.
Save yidas/af42d2952d85c0951c1722fcd68716c6 to your computer and use it in GitHub Desktop.
Certificate(CSR) configuration file

Openssl commands:

openssl genrsa -out self-ssl.key
openssl req -new -key self-ssl.key -out self-ssl.csr -config csr.conf
openssl x509 -req -days 365 -in self-ssl.csr -signkey self-ssl.key -out self-ssl.crt -extensions req_ext -extfile csr.conf

Sign from Root CA: openssl x509 -req -days 365 -extensions req_ext -extfile csr.conf -CA RootCA.crt -CAkey RootCA.key -in self-ssl.csr -out self-ssl.crt

Configuration csr.conf:

[req]
default_bits = 2048
distinguished_name = dn
prompt             = no
req_extensions = req_ext

[dn]
C="TW"
ST="Taiwan"
L="Taipei"
O="YIDAS"
OU="Service"
emailAddress="yourmail@mail.com"
CN="yourdomain.com"

[req_ext]
subjectAltName = @alt_names

[alt_names]
DNS.0 = *.yourdomain.com
DNS.1 = *.dev.yourdomain.com

[req] is for CSR with distinguished_name setting, while [req_ext] is called for -extensions with creating crt with SAN(subjectAltName) setting.

Extract information from the CSR/CRT

openssl req -in self-ssl.csr -text -noout
openssl x509 -in self-ssl.crt -text -noout

Trsuted CA or CRT

After building self-signed RootCA or CRT, you could install it into your browser client.

If you install RootCA or parent CRT, the SAN setting in the bottom CRT could be change by server with convenience, which the installer does not need to re-install CA.

@sramzln
Copy link

sramzln commented Sep 18, 2023

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment