module Falcon::Environment::TLS

def ssl_context
	OpenSSL::SSL::SSLContext.new.tap do |context|
		context.add_certificate(ssl_certificate, ssl_private_key, ssl_certificate_chain)
		
		context.session_cache_mode = OpenSSL::SSL::SSLContext::SESSION_CACHE_CLIENT
		context.session_id_context = ssl_session_id
		
		context.alpn_select_cb = lambda do |protocols|
			if protocols.include? "h2"
				return "h2"
			elsif protocols.include? "http/1.1"
				return "http/1.1"
			elsif protocols.include? "http/1.0"
				return "http/1.0"
			else
				return nil
			end
		end
		
		# TODO Ruby 2.4 requires using ssl_version.
		context.ssl_version = :TLSv1_2_server
		
		context.set_params(
			ciphers: ssl_ciphers,
			verify_mode: OpenSSL::SSL::VERIFY_NONE,
		)
		
		context.setup
	end
end