A chatroom made in C++ with the Qt librairy.

An expanded and updated version of Qt's example project : https://doc.qt.io/qt-6/qtnetwork-network-chat-example.html

The server mainainer needs to generate an SSL certificate that is signed with a CA certificate.

To enable internet communication, you need to port-forward TCP over port 59532.

Run the following command in an elevated powershell window:

winget install openssl

Then search for and run Win64 OpenSSL Command Prompt to enter the commands specified in the next step.

The following example will do 3 things:

• Generate a CA certificate that will be used by clients to verify that they are connecting to the right server.
• Generate a Csr+Key pair that will be used by the server to negotiate SSL connections with clients.
• Generate a signed certificate using the Csr and the CA certificate to allow clients to validate the server's identity.

1. Create the CA certificate:

openssl genrsa -out rootCA.key 2048
openssl req -x509 -new -key rootCA.key -days 365 -out rootCA.pem -subj "/C=AA/ST=AA/L=AA/O=AA Ltd/OU=AA/CN=AA/[email protected]"

2. Create the server csr and key pair:

openssl genrsa -out server.key 2048
openssl req -new -key server.key -out server.csr -subj "/C=BB/ST=BB/L=BB/O=BB Ltd/OU=BB/CN=BB/[email protected]"

3. Generate a signed certificate

openssl x509 -req -days 365 -CA rootCA.pem -CAkey rootCA.key -CAcreateserial -CAserial serial -in server.csr -out server.pem

You should now have these files:

• rootCA.key
• rootCA.pem
• server.key
• server.csr
• server.pem

You should now delete the following files for security:

• serial
• rootCA.key
• server.csr

(they serve no purpose to the applciation)

You should put server.key and server.pem in your server's SSL folder.

Each user wanting to connect to your server should get a copy of:

• Your rootCA.pem file in their client's SSL/ca/ folder.
• Your server.pem file in their client's SSL/public/ folder.

Note: you should rename the copies of rootCA.pem and server.pem to memorable names when handing them out to users in case they have multiple certificates to deal with.

This should be everything you need to get the server and clients to talk to each other over SSL using a secure protocol! 👍