Dining cryptographers

This is implementation of dining cryptographers protocol.

This app lets you run 3 instances of cryptographers and one instance of server. All instances communicates over TLS.

Below there is a list of ports, that instances are listening on.

Instance	Port
server	443
cryptographer 1	8081
cryptographer 2	8082
cryptographer 3	8083

Before running this app

IMPORTANT: To run this app you have to have valid go installation.

To run demonstration first it necessary to generate some certificates. You can do it by hand following instructions below, but there is also a script that will make it for you.

1. First of all we need CA root. To generate it we need a key for RSA.

   foo@bar:~$ openssl genrsa -out ./resources/CA/rootCA.key 4096

   Once you have RSA key, you can generate root certificate

   foo@bar:~$ openssl req -x509 -new -nodes -key ./resources/CA/rootCA.key -sha256 -days 1024 -out ./resources/CA/rootCA.crt

   Important: set Common Name to localhost

2. Now we have our self-signed root certificate. We can generate certificates for server and clients. Before we do certificates, we have to generate RSA keys for all of them. Lets begin with the server:

   foo@bar:~$ openssl genrsa -out ./resources/server/server.key 4096

   And then certificate signing request:

   foo@bar:~$ openssl req -new -key ./resources/server/server.key -out ./resources/server/server.csr

   And finally - certificate:

   foo@bar:~$ openssl x509 -req -in ./resources/server/server.csr -CA ./resources/CA/rootCA.crt -CAkey ./resources/CA/rootCA.key -CAcreateserial -out ./resources/server/server.crt -days 500 -sha256

3. Almost the same procedure will be for generating certificates for clients. Below there is an example for client. To generate certificates for client 2 and 3 you have to change 1 for 2 and 3 respectively.

   foo@bar:~$ openssl openssl genrsa -out ./resources/clients/keys/client1.key 4096
   foo@bar:~$ openssl req -new -key ./resources/clients/keys/client1.key -out ./resources/clients/crts/client1.csr
   foo@bar:~$ openssl x509 -req -in ./resources/clients/crts/client1.csr -CA ./resources/CA/rootCA.crt -CAkey ./resources/CA/rootCA.key -CAcreateserial -out ./resources/clients/crts/client1.crt -days 500 -sha256

You can do it the same using following script:

foo@bar:~$ sh ./resources/certificate_generator.sh

Now when everything is set up, you can finally run the demo.

How to run

1. Compiling sources:

   foo@bar:~$ go install ./...

2. To run the demo you need 4 terminal windows. Then run following commands( each one in separate terminal window) in this order. The order is important, because cryptographer with id 1 initiates flow.

   foo@bar1:~$ sudo runserver 
   foo@bar2:~$ runcryptographer -id=3 
   foo@bar2:~$ runcryptographer -id=2 
   foo@bar2:~$ runcryptographer -id=1 -payed=true 

After running last command, you should see who payed on every terminal.