tls.xml

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE nta PUBLIC '-//Uppaal Team//DTD Flat System 1.6//EN' 'http://www.it.uu.se/research/group/darts/uppaal/flat-1_6.dtd'>
<nta>
	<declaration>// Place global declarations here.
// note the values used are for demonstration purposes
//channel
chan clientHello;
chan serverHello;
chan passed;
chan clientKeyExchange;
chan fin_tls;
chan terminate;
chan session_fin;
// client_suite
int client_suite;
// 32 random generated by the client extra layer of security
const int client_random_byte = 66;
// 32 random generated by the server extra layer of security
const int server_random_byte = 88;
// public diffy hellman
const int g = 3;
const int n = 50;
int ag;
int bg;
bool valid_certificate = true;
const int hash_fin = 2;
int[0, 2147483647] power(int base, int e) {
    int[0, 2147483647] result = 1;
    int i;
    for(i = 0; i &lt; e; i++) {
        result = result * base;
    }
    return result;
}
int encrypt_fin;


</declaration>
	<template>
		<name x="5" y="5">Tls_client</name>
		<declaration>// Place local declarations here.
// note the values used are for demonstration purposes
const int a = 5;

int client_master_key ;

int decrypted_fin;

</declaration>
		<location id="id0" x="-1071" y="-204">
			<name x="-1096" y="-238">CLOSED</name>
		</location>
		<location id="id1" x="-425" y="-204">
			<name x="-476" y="-255">CLIENT_HELLO_SENT</name>
		</location>
		<location id="id2" x="-425" y="42">
			<name x="-510" y="59">SERVER_HELLO_RECIVED</name>
		</location>
		<location id="id3" x="178" y="-204">
			<name x="93" y="-246">CLIENT_KEY_EXCHANGE_SENT</name>
		</location>
		<location id="id4" x="178" y="195">
			<name x="102" y="229">FIN_TLS_INTEGRITY</name>
		</location>
		<location id="id5" x="1096" y="204">
			<name x="994" y="255">TLS_DONE_FULL_ENCRYT_MSG</name>
		</location>
		<init ref="id0"/>
		<transition id="id6">
			<source ref="id5"/>
			<target ref="id0"/>
			<label kind="synchronisation" x="-263" y="-807">session_fin?</label>
			<nail x="1062" y="-773"/>
			<nail x="-1300" y="-756"/>
			<nail x="-1300" y="-204"/>
		</transition>
		<transition id="id7">
			<source ref="id3"/>
			<target ref="id4"/>
			<label kind="synchronisation" x="340" y="-238">fin_tls?</label>
			<label kind="assignment" x="170" y="59">decrypted_fin = encrypt_fin/client_master_key</label>
			<nail x="553" y="-204"/>
			<nail x="561" y="85"/>
			<nail x="178" y="85"/>
		</transition>
		<transition id="id8">
			<source ref="id1"/>
			<target ref="id0"/>
			<label kind="synchronisation" x="-799" y="-51">terminate?</label>
			<nail x="-552" y="-25"/>
			<nail x="-901" y="-17"/>
		</transition>
		<transition id="id9">
			<source ref="id5"/>
			<target ref="id0"/>
			<label kind="synchronisation" x="-340" y="-552">session_fin!</label>
			<nail x="289" y="-527"/>
			<nail x="-799" y="-518"/>
			<nail x="-1020" y="-229"/>
		</transition>
		<transition id="id10">
			<source ref="id4"/>
			<target ref="id0"/>
			<label kind="guard" x="-646" y="212">!decrypted_fin == hash_fin</label>
			<label kind="synchronisation" x="-578" y="170">terminate!</label>
			<nail x="-603" y="204"/>
			<nail x="-1062" y="212"/>
		</transition>
		<transition id="id11">
			<source ref="id2"/>
			<target ref="id0"/>
			<label kind="guard" x="-824" y="51">!valid_certificate</label>
			<label kind="synchronisation" x="-985" y="16">terminate!</label>
			<nail x="-1003" y="42"/>
		</transition>
		<transition id="id12">
			<source ref="id4"/>
			<target ref="id5"/>
			<label kind="guard" x="484" y="221">decrypted_fin == hash_fin</label>
			<label kind="synchronisation" x="391" y="221">passed!</label>
		</transition>
		<transition id="id13">
			<source ref="id2"/>
			<target ref="id3"/>
			<label kind="guard" x="-110" y="51">valid_certificate</label>
			<label kind="synchronisation" x="-306" y="51">clientKeyExchange!</label>
			<label kind="assignment" x="-374" y="-8">ag=power(g,a)%n,client_master_key=power(bg,a)%n</label>
			<nail x="85" y="34"/>
			<nail x="76" y="-204"/>
		</transition>
		<transition id="id14">
			<source ref="id1"/>
			<target ref="id2"/>
			<label kind="synchronisation" x="-408" y="-110">serverHello?</label>
		</transition>
		<transition id="id15">
			<source ref="id0"/>
			<target ref="id1"/>
			<label kind="synchronisation" x="-884" y="-195">clientHello!</label>
			<label kind="assignment" x="-748" y="-195">client_suite=5</label>
		</transition>
	</template>
	<template>
		<name>Tls_server</name>
		<declaration>// note the values used are for demonstration purposes
// Server's supported cipher suites
const int SERVER_SUITES[4] = {1, 2, 5, 7};
const int SERVER_SUITE_COUNT = 4;

// Helper function to check if cipher suite is supported
bool is_suite_supported(int suite) {
    int i;
    for(i = 0; i &lt; SERVER_SUITE_COUNT; i++) {
        if(SERVER_SUITES[i] == suite) {
            return true;
        }
    }
    return false;
}

const int b = 2;

int server_master_key ;

</declaration>
		<location id="id16" x="-1156" y="-425">
			<name x="-1166" y="-459">CLOSED</name>
		</location>
		<location id="id17" x="603" y="-153">
			<name x="637" y="-162">CLIENT_HELLO_RECIVED</name>
		</location>
		<location id="id18" x="-289" y="-425">
			<name x="-298" y="-476">SERVER_HELLO_SENT</name>
		</location>
		<location id="id19" x="977" y="-450">
			<name x="875" y="-501">CLIENT_KEY_CHANGE_RECIVED</name>
		</location>
		<location id="id20" x="969" y="195">
			<name x="994" y="187">FIN_TLS_INTEGRITY</name>
		</location>
		<location id="id21" x="969" y="314">
			<name x="1003" y="306">TLS_DONE_FULL_ENCRYT_MSG</name>
		</location>
		<init ref="id16"/>
		<transition id="id22">
			<source ref="id21"/>
			<target ref="id16"/>
			<label kind="synchronisation" x="-212" y="416">session_fin!</label>
			<nail x="969" y="450"/>
			<nail x="-1215" y="442"/>
			<nail x="-1215" y="-425"/>
		</transition>
		<transition id="id23">
			<source ref="id17"/>
			<target ref="id16"/>
			<label kind="guard" x="-433" y="136">!is_suite_supported(client_suite)</label>
			<label kind="synchronisation" x="-348" y="76">terminate!</label>
			<nail x="612" y="93"/>
			<nail x="-952" y="127"/>
		</transition>
		<transition id="id24">
			<source ref="id21"/>
			<target ref="id16"/>
			<label kind="synchronisation" x="-238" y="289">session_fin?</label>
			<nail x="952" y="314"/>
			<nail x="-1122" y="323"/>
		</transition>
		<transition id="id25">
			<source ref="id20"/>
			<target ref="id16"/>
			<label kind="synchronisation" x="-255" y="221">terminate?</label>
			<nail x="-1054" y="212"/>
		</transition>
		<transition id="id26">
			<source ref="id18"/>
			<target ref="id16"/>
			<label kind="guard" x="-705" y="-450">!valid_certificate</label>
			<label kind="synchronisation" x="-731" y="-391">terminate?</label>
			<nail x="-314" y="-425"/>
		</transition>
		<transition id="id27">
			<source ref="id20"/>
			<target ref="id21"/>
			<label kind="synchronisation" x="977" y="246">passed?</label>
		</transition>
		<transition id="id28">
			<source ref="id19"/>
			<target ref="id20"/>
			<label kind="synchronisation" x="943" y="-136">fin_tls!</label>
			<label kind="assignment" x="782" y="-323">encrypt_fin=hash_fin*server_master_key</label>
		</transition>
		<transition id="id29">
			<source ref="id18"/>
			<target ref="id19"/>
			<label kind="guard" x="144" y="-467">valid_certificate</label>
			<label kind="synchronisation" x="144" y="-425">clientKeyExchange?</label>
			<label kind="assignment" x="357" y="-433">server_master_key=power(ag,b)%50</label>
		</transition>
		<transition id="id30">
			<source ref="id17"/>
			<target ref="id18"/>
			<label kind="guard" x="-76" y="-348">is_suite_supported(client_suite)</label>
			<label kind="synchronisation" x="-102" y="-289">serverHello!</label>
			<label kind="assignment" x="42" y="-289">bg=power(g,b)%n</label>
			<nail x="603" y="-323"/>
			<nail x="-289" y="-297"/>
		</transition>
		<transition id="id31">
			<source ref="id16"/>
			<target ref="id17"/>
			<label kind="synchronisation" x="-433" y="-195">clientHello?</label>
			<nail x="-892" y="-136"/>
			<nail x="552" y="-161"/>
		</transition>
	</template>
	<system>// Place template instantiations here.
C = Tls_client();
S = Tls_server();
// List one or more processes to be composed into a system.
system C,S;
</system>
	<queries>
		<query>
			<formula>A[] not deadlock
// System never deadlocks</formula>
			<comment/>
			<result outcome="success" type="quality" timestamp="2025-11-19 17:03:27 +0100">
			</result>
		</query>
	</queries>
</nta>