half finished oneswarm community server in ruby

require "rubygems"
require "sinatra"
require "pstore"
require "openssl"
require "base64"


configure do
 set :data_store, PStore.new("users.pstore")
end

helpers do
	def sendpeers
		"<Friend Base64Key='123451234512345' nick='NARF_TEST' />"
	end
	
end



get '/community' do
	puts "received get request"
	#let's check if there is a key
	if params["base64key"].nil?
		puts "No key received!"
		error(400, "No key provided.")
	else
		puts "The requests key is #{params["base64key"]}"
	end
	
	base64key = params["base64key"]
	
	options.data_store.transaction do 
	if options.data_store[base64key].nil?
		error(401, "Unauthorized")
	else
	#let's update the clients IP
		options.data_store[base64key][:last_ip] = @env['REMOTE_ADDR']
	end
	
	
	if params["resp"].nil?
		#no response found --> create and ask a challenge
		my_challenge = rand(16777215)
		options.data_store[base64key]["challenge"] = my_challenge
		return "CHALLENGE #{my_challenge}"
	else
		#response found, let's check if it's the right one
		if options.data_store[base64key]["challenge"].nil?
			error(401, "No recent challenge for key")
		else
			#save the challenge to a variable...
			my_challenge = options.data_store[base64key]["challenge"]
			#...and delete it from the store
			options.data_store[base64key]["challenge"] = nil
			begin
				my_public_key = OpenSSL::PKey::RSA.new("-----BEGIN PUBLIC KEY-----\n#{base64key}-----END PUBLIC KEY-----\n")
			rescue Exception
				error(400, "Error decoding key")
			end
			
			begin
				decoded_response =  Base64.decode64(params["resp"])
			rescue Exception
				error(400, "Error decoding response")
			end
			
			begin
				if (my_public_key.ssh_do_verify(decoded_response, my_challenge)) #(sig, data)
					return_value << "<?xml version='1.0'?>\n"
					return_value << "<CommunityServerResponse>\n"
					if params[:refresh].nil?
						return_value << "<RefreshInterval>#{params[:refresh]}</RefreshInterval>";
					end
					return_value << "<FriendList>\n"
					return_value << sendpeers()
					return_value << "</FriendList>\n"
					return_value << "</CommunityServerResponse>"
				end
			rescue Exception
				error(400, "Something went wrong")
			end
		end
	end
end

post '/community' do
	puts "received post request"
	#let's check if there is a key
	if params["base64key"].nil?
		puts "No key received!"
		error(400, "No key provided.")
	else
		puts "The requests key is #{params["base64key"]}"
	end
	
	if params["nick"].nil?
		puts "No key received!"
			error(400, "No nickname provided.")
		else
			puts "The nickname is #{params["nick"]}"
	end
	
	#put the params into nice little variables
	base64key = params["base64key"]
	nickname = params["nick"]
	
	#write data to the pstore file
	options.data_store.transaction do 
		if options.data_store[base64key].nil?
			options.data_store[base64key] = {:nickname => nickname, :last_ip => @env['REMOTE_ADDR']}
			puts "Added user to pstore"
			return "REGISTRATION_OK"
		else
			return "REGISTRATION_DUPLICATE"	
			puts "User was already in pstore"
	end
end
end
end