Formatting and performance measurements

This commit is contained in:
Patrick Rathje 2020-11-19 16:56:33 +01:00
parent b211d716e3
commit 69952363f5
2 changed files with 232 additions and 76 deletions

View File

@ -22,6 +22,7 @@ build_flags =
# For testing: -DUNITY_EXCLUDE_SETJMP_H=1
-DEN_INCLUDE_ZEPHYR_DEPS=1
-DEN_INIT_MBEDTLS_ENTROPY=0
-DCOVID_MEASURE_PERFORMANCE=0 # Used to measure device performance
lib_deps =
prathje/exposure-notification @ ^0.1
lib_ignore =

View File

@ -18,13 +18,18 @@
#include "contacts.h"
#include "covid.h"
typedef struct covid_adv_svd {
#ifndef COVID_MEASURE_PERFORMANCE
#define COVID_MEASURE_PERFORMANCE 0
#endif
typedef struct covid_adv_svd
{
uint16_t ens;
rolling_proximity_identifier_t rolling_proximity_identifier;
associated_encrypted_metadata_t associated_encrypted_metadata;
} __packed covid_adv_svd_t;
} __packed covid_adv_svd_t;
const static bt_metadata_t bt_metadata= {
const static bt_metadata_t bt_metadata = {
.version = 0b00100000,
.tx_power = 0, //TODO set to actual transmit power
.rsv1 = 0,
@ -33,42 +38,46 @@ const static bt_metadata_t bt_metadata= {
#define COVID_ENS (0xFD6F)
static covid_adv_svd_t covid_adv_svd= {
static covid_adv_svd_t covid_adv_svd = {
.ens = COVID_ENS,
//do not initialiuze the rest of the packet, will write this later
};
static struct bt_data ad[] = {
BT_DATA_BYTES(BT_DATA_FLAGS, (BT_LE_AD_GENERAL | BT_LE_AD_NO_BREDR)),
BT_DATA_BYTES(BT_DATA_UUID16_ALL, 0x6f, 0xfd), //0xFD6F Exposure Notification Service
BT_DATA(BT_DATA_SVC_DATA16, &covid_adv_svd, sizeof(covid_adv_svd_t))
};
BT_DATA_BYTES(BT_DATA_FLAGS, (BT_LE_AD_GENERAL | BT_LE_AD_NO_BREDR)),
BT_DATA_BYTES(BT_DATA_UUID16_ALL, 0x6f, 0xfd), //0xFD6F Exposure Notification Service
BT_DATA(BT_DATA_SVC_DATA16, &covid_adv_svd, sizeof(covid_adv_svd_t))};
static void scan_cb(const bt_addr_le_t *addr, int8_t rssi, uint8_t adv_type, struct net_buf_simple *buf)
static void scan_cb(const bt_addr_le_t *addr, int8_t rssi, uint8_t adv_type, struct net_buf_simple *buf)
{
if( adv_type == 3 ){
if (adv_type == 3)
{
uint8_t len = 0;
while (buf->len > 1) {
while (buf->len > 1)
{
uint8_t type;
len = net_buf_simple_pull_u8(buf);
if (!len) {
if (!len)
{
break;
}
/* Check if field length is correct */
if (len > buf->len || buf->len < 1) {
if (len > buf->len || buf->len < 1)
{
break;
}
type = net_buf_simple_pull_u8(buf);
if (type == BT_DATA_SVC_DATA16 && len == sizeof(covid_adv_svd_t) + 1){
covid_adv_svd_t* rx_adv = (covid_adv_svd_t*) buf->data;
if (rx_adv->ens == COVID_ENS){
if (type == BT_DATA_SVC_DATA16 && len == sizeof(covid_adv_svd_t) + 1)
{
covid_adv_svd_t *rx_adv = (covid_adv_svd_t *)buf->data;
if (rx_adv->ens == COVID_ENS)
{
check_add_contact(k_uptime_get() / 1000, &rx_adv->rolling_proximity_identifier, &rx_adv->associated_encrypted_metadata, rssi);
}
}
net_buf_simple_pull(buf, len - 1); //consume the rest, note we already consumed one byte via net_buf_simple_pull_u8(buf)
net_buf_simple_pull(buf, len - 1); //consume the rest, note we already consumed one byte via net_buf_simple_pull_u8(buf)
}
}
}
@ -87,37 +96,41 @@ static associated_encrypted_metadata_t encryptedMetadata;
static bool init = 1;
static bool infected = 0;
static void test_against_fixtures(void)
{
// First define base values
ENIntervalNumber intervalNumber = 2642976;
ENPeriodKey periodKey = {.b = {0x75, 0xc7, 0x34, 0xc6, 0xdd, 0x1a, 0x78, 0x2d, 0xe7, 0xa9, 0x65, 0xda, 0x5e, 0xb9, 0x31, 0x25}};
unsigned char metadata[4] = {0x40, 0x08, 0x00, 0x00};
// define the expected values
ENPeriodIdentifierKey expectedPIK = {.b = {0x18, 0x5a, 0xd9, 0x1d, 0xb6, 0x9e, 0xc7, 0xdd, 0x04, 0x89, 0x60, 0xf1, 0xf3, 0xba, 0x61, 0x75}};
ENPeriodMetadataEncryptionKey expectedPMEK = {.b = {0xd5, 0x7c, 0x46, 0xaf, 0x7a, 0x1d, 0x83, 0x96, 0x5b, 0x9b, 0xed, 0x8b, 0xd1, 0x52, 0x93, 0x6a}};
static void test_against_fixtures(void) {
// First define base values
ENIntervalNumber intervalNumber = 2642976;
ENPeriodKey periodKey = {.b = {0x75, 0xc7, 0x34, 0xc6, 0xdd, 0x1a, 0x78, 0x2d, 0xe7, 0xa9, 0x65, 0xda, 0x5e, 0xb9, 0x31, 0x25}};
unsigned char metadata[4] = {0x40, 0x08, 0x00, 0x00};
ENIntervalIdentifier expectedIntervalIdentifier = {.b = {0x8b, 0xe6, 0xcd, 0x37, 0x1c, 0x5c, 0x89, 0x16, 0x04, 0xbf, 0xbe, 0x49, 0xdf, 0x84, 0x50, 0x96}};
unsigned char expectedEncryptedMetadata[4] = {0x72, 0x03, 0x38, 0x74};
// define the expected values
ENPeriodIdentifierKey expectedPIK = {.b = {0x18, 0x5a, 0xd9, 0x1d, 0xb6, 0x9e, 0xc7, 0xdd, 0x04, 0x89, 0x60, 0xf1, 0xf3, 0xba, 0x61, 0x75}};
ENPeriodMetadataEncryptionKey expectedPMEK = {.b = {0xd5, 0x7c, 0x46, 0xaf, 0x7a, 0x1d, 0x83, 0x96, 0x5b, 0x9b, 0xed, 0x8b, 0xd1, 0x52, 0x93, 0x6a}};
ENPeriodIdentifierKey pik;
en_derive_period_identifier_key(&pik, &periodKey);
ENIntervalIdentifier expectedIntervalIdentifier = {.b = {0x8b, 0xe6, 0xcd, 0x37, 0x1c, 0x5c, 0x89, 0x16, 0x04, 0xbf, 0xbe, 0x49, 0xdf, 0x84, 0x50, 0x96}};
unsigned char expectedEncryptedMetadata[4] = {0x72, 0x03, 0x38, 0x74};
ENPeriodIdentifierKey pik;
en_derive_period_identifier_key(&pik, &periodKey);
printk("expectedPIK: "); print_key(&expectedPIK); printk(", ");
printk("actualPIK: "); print_key(&pik); printk(", ");
printk("expectedPIK: ");
print_key(&expectedPIK);
printk(", ");
printk("actualPIK: ");
print_key(&pik);
printk(", ");
ENIntervalIdentifier intervalIdentifier;
en_derive_interval_identifier(&intervalIdentifier, &pik, intervalNumber);
en_derive_interval_identifier(&intervalIdentifier, &pik, intervalNumber);
printk("expectedRPI: "); print_key(&expectedIntervalIdentifier); printk(", ");
printk("actualRPI: "); print_key(&intervalIdentifier); printk(", ");
printk("expectedRPI: ");
print_key(&expectedIntervalIdentifier);
printk(", ");
printk("actualRPI: ");
print_key(&intervalIdentifier);
printk(", ");
/*ENPeriodMetadataEncryptionKey pmek;
/*ENPeriodMetadataEncryptionKey pmek;
en_derive_period_metadata_encryption_key(&pmek, &periodKey);
TEST_ASSERT_EQUAL_KEY(expectedPMEK, pmek);
@ -126,8 +139,8 @@ static void test_against_fixtures(void) {
TEST_ASSERT_EQUAL_CHAR_ARRAY(expectedEncryptedMetadata, encryptedMetadata, sizeof(expectedEncryptedMetadata));*/
}
static void new_period_key(time_t currentTime ){
static void new_period_key(time_t currentTime)
{
printk("\n----------------------------------------\n\n");
printk("\n----------------------------------------\n\n");
printk("*** New Period\n");
@ -138,42 +151,166 @@ static void new_period_key(time_t currentTime ){
period_cnt++;
}
#if COVID_MEASURE_PERFORMANCE
static void measure_performance()
{
u32_t runs = 100;
u32_t start_time;
u32_t cycles_spent;
u32_t nanoseconds_spent;
ENPeriodKey pk;
ENPeriodIdentifierKey pik;
ENIntervalIdentifier intervalIdentifier;
ENIntervalNumber intervalNumber = 2642976;
ENIntervalIdentifier id;
ENPeriodMetadataEncryptionKey pmek;
unsigned char metadata[4] = {0x40, 0x08, 0x00, 0x00};
unsigned char encryptedMetadata[sizeof(metadata)] = {0};
printk("\n----------------------------------------\n");
printk("MEASURING PERFORMANCE\n");
// Measure en_generate_period_key
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
en_generate_period_key(&pk);
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("en_generate_period_key %d ns\n", nanoseconds_spent/runs);
}
// Measure en_derive_period_identifier_key
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
en_derive_period_identifier_key(&pik, &pk);
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("en_derive_period_identifier_key %d ns\n", nanoseconds_spent/runs);
}
// Measure en_derive_interval_identifier
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
en_derive_interval_identifier(&intervalIdentifier, &pik, intervalNumber);
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("en_derive_interval_identifier %d ns\n", nanoseconds_spent/runs);
}
// Measure en_derive_period_metadata_encryption_key
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
en_derive_period_metadata_encryption_key(&pmek, &pk);
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("en_derive_period_metadata_encryption_key %d ns\n", nanoseconds_spent/runs);
}
// Measure en_encrypt_interval_metadata
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
en_encrypt_interval_metadata(&pmek, &intervalIdentifier, metadata, encryptedMetadata, sizeof(metadata));
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("en_encrypt_interval_metadata %d ns\n", nanoseconds_spent/runs);
}
// Measure Full key generation
{
start_time = k_cycle_get_32();
for (int i = 0; i < runs; i++)
{
ENPeriodKey pk;
en_generate_period_key(&pk);
ENPeriodIdentifierKey ik;
en_derive_period_identifier_key(&ik, &pk);
for(int iv = 0; iv < EN_TEK_ROLLING_PERIOD; iv++) {
ENIntervalNumber intervalNumber = en_get_interval_number(iv);
ENIntervalIdentifier id;
en_derive_interval_identifier(&id, &ik, intervalNumber);
}
}
nanoseconds_spent = SYS_CLOCK_HW_CYCLES_TO_NS(k_cycle_get_32() - start_time);
printk("Full key generation %d ns\n", nanoseconds_spent/runs);
}
printk("\FINISHED\n");
printk("----------------------------------------\n\n");
}
#endif
//To be called when new keys are needed
static void check_keys(struct k_work *work){
static void check_keys(struct k_work *work)
{
// we check the current time to know if we actually need to regenerate anything
// TODO: Use real unix timestamp!: currentTime = time(NULL);
time_t currentTime = k_uptime_get() / 1000;
ENIntervalNumber newInterval = en_get_interval_number(currentTime);
if( currentInterval != newInterval || init){
if (currentInterval != newInterval || init)
{
currentInterval = newInterval;
bool newPeriod = ((currentInterval - periods[current_period_index].periodInterval) >= EN_TEK_ROLLING_PERIOD);
// we check if we need to generate new keys
if (newPeriod || init) {
if (newPeriod || init)
{
new_period_key(currentTime);
}
// we now generate the new interval identifier and re-encrypt the metadata
en_derive_interval_identifier(&intervalIdentifier, &periods[current_period_index].periodKey, currentInterval);
en_derive_period_metadata_encryption_key(&periodMetadataEncryptionKey, &periods[current_period_index].periodKey);
en_encrypt_interval_metadata(&periodMetadataEncryptionKey, &intervalIdentifier, (unsigned char*)&bt_metadata, (unsigned char*)&encryptedMetadata, sizeof(associated_encrypted_metadata_t));
en_derive_period_metadata_encryption_key(&periodMetadataEncryptionKey, &periods[current_period_index].periodKey);
en_encrypt_interval_metadata(&periodMetadataEncryptionKey, &intervalIdentifier, (unsigned char *)&bt_metadata, (unsigned char *)&encryptedMetadata, sizeof(associated_encrypted_metadata_t));
// broadcast intervalIdentifier plus encryptedMetada according to specs
//printk("\n----------------------------------------\n\n");
printk("Time: %llu, ", currentTime);
printk("Interval: %u, ", currentInterval);
printk("TEK: "); print_rpi((rolling_proximity_identifier_t*)&periods[current_period_index].periodKey); printk(", ");
printk("RPI: "); print_rpi((rolling_proximity_identifier_t*)&intervalIdentifier); printk(", ");
printk("AEM: "); print_aem(&encryptedMetadata); printk("\n");
printk("TEK: ");
print_rpi((rolling_proximity_identifier_t *)&periods[current_period_index].periodKey);
printk(", ");
printk("RPI: ");
print_rpi((rolling_proximity_identifier_t *)&intervalIdentifier);
printk(", ");
printk("AEM: ");
print_aem(&encryptedMetadata);
printk("\n");
//TODO do we have to worry about race conditions here?
//worst case: we would be advertising a wrong key for a while
memcpy(&covid_adv_svd.rolling_proximity_identifier, &intervalIdentifier, sizeof(rolling_proximity_identifier_t));
memcpy(&covid_adv_svd.associated_encrypted_metadata, &encryptedMetadata, sizeof(associated_encrypted_metadata_t));
if( !init ){
if (!init)
{
key_change(current_period_index);
}
init = 0;
@ -182,22 +319,28 @@ static void check_keys(struct k_work *work){
K_WORK_DEFINE(my_work, check_keys);
static void my_timer_handler(struct k_timer *dummy){
k_work_submit(&my_work);
static void my_timer_handler(struct k_timer *dummy)
{
k_work_submit(&my_work);
}
K_TIMER_DEFINE(my_timer, my_timer_handler, NULL);
static const struct bt_le_scan_param scan_param = {
.type = BT_HCI_LE_SCAN_PASSIVE,
.type = BT_HCI_LE_SCAN_PASSIVE,
.filter_dup = BT_HCI_LE_SCAN_FILTER_DUP_DISABLE,
.interval = 0x0010, //Scan Interval (N * 0.625 ms), TODO: set to correct interval
.window = 0x0010, //Scan Window (N * 0.625 ms), TODO: set to correct interval
.interval = 0x0010, //Scan Interval (N * 0.625 ms), TODO: set to correct interval
.window = 0x0010, //Scan Window (N * 0.625 ms), TODO: set to correct interval
};
#define KEY_CHECK_INTERVAL (K_MSEC(EN_INTERVAL_LENGTH * 1000 / 10))
int init_covid(){
int init_covid()
{
#if COVID_MEASURE_PERFORMANCE
measure_performance();
#endif
// TODO: Use real unix timestamp!: currentTime = time(NULL);
init = 1;
@ -210,31 +353,34 @@ int init_covid(){
int err = 0;
err = bt_le_scan_start(&scan_param, scan_cb);
if (err) {
if (err)
{
printk("Starting scanning failed (err %d)\n", err);
return err;
}
k_timer_start(&my_timer, KEY_CHECK_INTERVAL, KEY_CHECK_INTERVAL);
return 0;
}
int do_covid(){
int do_covid()
{
//printk("covid start\n");
int err = 0;
int err = 0;
err = bt_le_adv_start(BT_LE_ADV_NCONN, ad, ARRAY_SIZE(ad), NULL, 0);
if (err) {
if (err)
{
printk("Advertising failed to start (err %d)\n", err);
return err;
}
}
k_sleep(K_SECONDS(10));
err = bt_le_adv_stop();
if (err) {
if (err)
{
printk("Advertising failed to stop (err %d)\n", err);
return err;
}
@ -242,23 +388,29 @@ int do_covid(){
return 0;
}
bool get_infection(){
bool get_infection()
{
return infected;
}
void set_infection(bool _infected){
void set_infection(bool _infected)
{
infected = _infected;
}
unsigned int get_period_cnt_if_infected(){
if( !infected ){
unsigned int get_period_cnt_if_infected()
{
if (!infected)
{
return 0;
}
return period_cnt;
}
period_t* get_period_if_infected(unsigned int id, size_t* size){
if( !infected || id >= NUM_PERIOD_KEYS || id >= period_cnt ){
period_t *get_period_if_infected(unsigned int id, size_t *size)
{
if (!infected || id >= NUM_PERIOD_KEYS || id >= period_cnt)
{
*size = 0;
return NULL;
}
@ -266,10 +418,13 @@ period_t* get_period_if_infected(unsigned int id, size_t* size){
return &periods[id];
}
int get_index_by_interval(ENIntervalNumber periodInterval){
int get_index_by_interval(ENIntervalNumber periodInterval)
{
int index = 0;
while( index < NUM_PERIOD_KEYS || index < period_cnt ){
if( periods[index].periodInterval == periodInterval){
while (index < NUM_PERIOD_KEYS || index < period_cnt)
{
if (periods[index].periodInterval == periodInterval)
{
return index;
}
index++;