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How to create an HTTPS certificate for localhost domains

How to create an HTTPS certificate for localhost domains

This focuses on generating the certificates for loading local virtual hosts hosted on your computer, for development only.

Do not use self-signed certificates in production ! For online certificates, use Let's Encrypt instead (tutorial).

Certificate authority (CA)

Generate RootCA.pem, RootCA.key & RootCA.crt:

openssl req -x509 -nodes -new -sha256 -days 1024 -newkey rsa:2048 -keyout RootCA.key -out RootCA.pem -subj "/C=US/CN=Example-Root-CA"
openssl x509 -outform pem -in RootCA.pem -out RootCA.crt

Note that Example-Root-CA is an example, you can customize the name.

Domain name certificate

Let's say you have two domains fake1.local and fake2.local that are hosted on your local machine for development (using the hosts file to point them to 127.0.0.1).

First, create a file domains.ext that lists all your local domains:

authorityKeyIdentifier=keyid,issuer
basicConstraints=CA:FALSE
keyUsage = digitalSignature, nonRepudiation, keyEncipherment, dataEncipherment
subjectAltName = @alt_names
[alt_names]
DNS.1 = localhost
DNS.2 = fake1.local
DNS.3 = fake2.local

Generate localhost.key, localhost.csr, and localhost.crt:

openssl req -new -nodes -newkey rsa:2048 -keyout localhost.key -out localhost.csr -subj "/C=US/ST=YourState/L=YourCity/O=Example-Certificates/CN=localhost.local"
openssl x509 -req -sha256 -days 1024 -in localhost.csr -CA RootCA.pem -CAkey RootCA.key -CAcreateserial -extfile domains.ext -out localhost.crt

Note that the country / state / city / name in the first command can be customized.

You can now configure your webserver, for example with Apache:

SSLEngine on
SSLCertificateFile "C:/example/localhost.crt"
SSLCertificateKeyFile "C:/example/localhost.key"

Trust the local CA

At this point, the site would load with a warning about self-signed certificates. In order to get a green lock, your new local CA has to be added to the trusted Root Certificate Authorities.

Windows 10: Chrome, IE11 & Edge

Windows 10 recognizes .crt files, so you can right-click on RootCA.crt > Install to open the import dialog.

Make sure to select "Trusted Root Certification Authorities" and confirm.

You should now get a green lock in Chrome, IE11 and Edge.

Windows 10: Firefox

There are two ways to get the CA trusted in Firefox.

The simplest is to make Firefox use the Windows trusted Root CAs by going to about:config, and setting security.enterprise_roots.enabled to true.

The other way is to import the certificate by going to about:preferences#privacy > Certificats > Import > RootCA.pem > Confirm for websites.

@frank-stonybrook
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Need an easy solution: https://github.com/FiloSottile/mkcert

You saved my day! Thanks!

@magi-web
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magi-web commented Jan 8, 2023

Thank you so much ! It works like a charm <3

@peppeg85
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peppeg85 commented Feb 8, 2023

hello, if i need to add more hosts in the future, i have to update the domain.ext file and re-generate the certificates with the two instructions

openssl req -new -nodes -newkey rsa:2048 -keyout localhost.key -out localhost.csr -subj "/C=US/ST=YourState/L=YourCity/O=Example-Certificates/CN=localhost.local"
openssl x509 -req -sha256 -days 1024 -in localhost.csr -CA RootCA.pem -CAkey RootCA.key -CAcreateserial -extfile domains.ext -out localhost.crt

and another question: in the domain.ext file, the entries authorityKeyIdentifier=keyid,issuer how should be valorized?
thank you

@daxlai
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daxlai commented Feb 8, 2023 via email

@peppeg85
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peppeg85 commented Feb 9, 2023

follow the guide, on windows you ave to add hosts inside the hosts

C:\Windows\System32\drivers\etc\hosts 

if you can't see it enable hidden files in the system explorer. then add entries like
127.0.0.1 www.fake1.local (the entries inside the domains.ext file), do this with notepad++, it will ask you to save as administrator.

maybe you need to disconnect and reconnect windows.
if still doesn't work try to use CN=*.localhost.local for this instruction:

openssl req -new -nodes -newkey rsa:2048 -keyout localhost.key -out localhost.csr -subj "/C=US/ST=YourState/L=YourCity/O=Example-Certificates/CN=localhost.local"

then i use this with spring boot, so i had to convert the crt file to p12

@BraxtonI
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BraxtonI commented Feb 9, 2023 via email

@b-and-p
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b-and-p commented Apr 14, 2023

Excellent information, thanks! I was struggling with Chrome and Wampserver for a week before I saw this. Worked like a charm!

@DragonOsman
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DragonOsman commented Jun 20, 2023

I want to do this for a MERN app I'm trying to develop and test locally that uses JWTs for authentication. Without HTTPS, the cookies would be ignored by the browser since I'd need to use secure cookies.

I think I successfully generated the .crt file using my .csr and .key files, but now when I try to visit https://localhost:3000 or https://localhost.local:3000 I get an error. What do I need to do from here?

Edit: I've installed the .crt file to the store (type of store left up to the wizard) and I've added "localhost" with port 3000 to my hosts, but it's still telling me that the site isn't secure when I try to visit it in MS Edge. Please help. Thanks.

Edit2: Okay, I've also added the cert file to the trusted store in mmc.exe but still doesn't work. I still get the error that the site isn't secure. What should I do?

@MickaelDuprat
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Wow awesome, thank you so much for your tutorial ! :)

@ChiyungWu
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Thanks for your tutorial, it solve my problem!!

@pixelfast
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pixelfast commented Sep 18, 2023

So, SSL on localhost now works fine, and displays the Wampserver Homepage.

I now have Your Virtual Hosts listed as:

mortgagequest:8080

In my httpd-vhosts.conf file, the entry looks like this:

<VirtualHost *:8080> ServerName mortgagequest DocumentRoot "c:/mysites/azmortgage/new" <Directory "c:/mysites/azmortgage/new/"> Options +Indexes +Includes +FollowSymLinks +MultiViews AllowOverride All Require local </Directory> </VirtualHost>

My hosts file has this entry:

127.0.0.1 mortgagequest
::1 mortgagequest

When I browse to https://mortgagequest I get the Wampserver Homepage.

What further steps do I need to take to enable SSL for the virtual host?

Thank you!

@alpheus-madsen
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Is there a way to use the SSL certificate directly for localhost sites, without installing a web server of some sort? While I can go down that route, I'd rather stay with the simplicity of resolving things using "/etc/hosts"!

@perki
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perki commented Jan 25, 2024

@alpheus-madsen To serve HTTPS you need an web server.
As a one liner solution, if you have nodejs installed, do npx backloop.dev <path to serve>, this will provide a localhost SSL certificate plus a minimal web server.

@marcus-at-localhost
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Unfortunately, I got this:

name is expected to be in the format /type0=value0/type1=value1/type2=... where characters may be escaped by . This name is not in that format: 'E:/xampp/Git/C=US/ST=YourState/L=YourCity/O=Example-Certificates/CN=localhost'
problems making Certificate Request

Honestly, I have no idea what I am doing :D, but I was successful using this: https://github.com/FiloSottile/mkcert

Thanks to everyone sharing their knowledge!

@hgati
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hgati commented Feb 23, 2024

Great thanks. Perfect solution !!

@daxlai
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daxlai commented Feb 25, 2024

screen-shoot
here is my server.xml file ssl config part




<Connector port="8443" protocol="org.apache.coyote.http11.Http11NioProtocol"
           maxThreads="150" SSLEnabled="true">
    <UpgradeProtocol className="org.apache.coyote.http2.Http2Protocol" />
    <SSLHostConfig>
	  <Certificate SSLCertificateFile="localhost.crt"
       SSLCertificateKeyFile="localhost.key" />
    </SSLHostConfig>
</Connector>

SHOWING THAT CERTIFICATE NOT SECURE

@thangaraj-sellappan
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It worked with one more command addition to that. Found the solution here

openssl pkcs12 -export -out localhost.local.pfx -inkey localhost.local.key -in localhost.local.crt

localhost.local is the custom domain as an example.

@3201755129
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3201755129 commented Aug 3, 2024

Thank you very much. I have spend many hours on it untill running into your article.
Windows 10, phpstudy pane, nginx1.15.11
PS:As for how to config the localhost.key and localhost.crt to nginx1.15.11, you can generate the .key file and the .crt file first and then generate the website in phpstudy ,because you can just pull the .key and .crt file into the .key location and .pem location at the config pane.
I'm not sure if it works when you set up you website first and then change your config.

@hasnahadd
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thank you so much

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