I've been reading a lot of things about sniffing whatsapp traffic and I already know is over ssl. 
But I need to know if is there any way to decrypt this ssl traffic once I dont know what is the private key that whatsapp is using for encrypting.

So how could I discover which certificate is being used or whether exists another way to decrypt those messages?

I dont want to read anybody's chats, my intention is really se the protocols messages through the network. To understand, make a reverse engineering and elaborate a simple JAVA api to personal job purposes.

I'm using wireshark to read the ssl traffic.

![screenshot of a capture of a whatsapp chat](https://i.stack.imgur.com/0REeh.png)