dandri/MeshCore
1
0
Fork 0
mirror of https://github.com/meshcore-dev/MeshCore.git synced 2026-03-30 14:55:46 +00:00
Code Issues Packages Projects Releases Wiki Activity
Files
810b1f8fe7a9d0d90a63fc8b775a38897f7f0d96
MeshCore/examples/simple_sensor/SensorMesh.cpp
Scott Powell 810b1f8fe7 * Mesh::onAnonDataRecv() slight optimisation, so that shared-secret calc doesn't need to be repeated 
* SensporMesh: req_type now optionally encoded in anon_req payload (so can send various requests without a prior login)
2025-07-08 23:19:35 +10:00

606 lines
20 KiB
C++
Raw Blame History

#include "SensorMesh.h"
/* ------------------------------ Config -------------------------------- */
#ifndef LORA_FREQ
#define LORA_FREQ 915.0
#endif
#ifndef LORA_BW
#define LORA_BW 250
#endif
#ifndef LORA_SF
#define LORA_SF 10
#endif
#ifndef LORA_CR
#define LORA_CR 5
#endif
#ifndef LORA_TX_POWER
#define LORA_TX_POWER 20
#endif
#ifndef ADVERT_NAME
#define ADVERT_NAME "sensor"
#endif
#ifndef ADVERT_LAT
#define ADVERT_LAT 0.0
#endif
#ifndef ADVERT_LON
#define ADVERT_LON 0.0
#endif
#ifndef ADMIN_PASSWORD
#define ADMIN_PASSWORD "password"
#endif
#ifndef SERVER_RESPONSE_DELAY
#define SERVER_RESPONSE_DELAY 300
#endif
#ifndef TXT_ACK_DELAY
#define TXT_ACK_DELAY 200
#endif
#ifndef SENSOR_READ_INTERVAL_SECS
#define SENSOR_READ_INTERVAL_SECS 60
#endif
/* ------------------------------ Code -------------------------------- */
#define REQ_TYPE_LOGIN 0x00
#define REQ_TYPE_GET_STATUS 0x01
#define REQ_TYPE_KEEP_ALIVE 0x02
#define REQ_TYPE_GET_TELEMETRY_DATA 0x03
#define RESP_SERVER_LOGIN_OK 0 // response to ANON_REQ
#define CLI_REPLY_DELAY_MILLIS 1000
#define LAZY_CONTACTS_WRITE_DELAY 5000
static File openAppend(FILESYSTEM* _fs, const char* fname) {
#if defined(NRF52_PLATFORM) || defined(STM32_PLATFORM)
return _fs->open(fname, FILE_O_WRITE);
#elif defined(RP2040_PLATFORM)
return _fs->open(fname, "a");
#else
return _fs->open(fname, "a", true);
#endif
}
static File openWrite(FILESYSTEM* _fs, const char* filename) {
#if defined(NRF52_PLATFORM) || defined(STM32_PLATFORM)
_fs->remove(filename);
return _fs->open(filename, FILE_O_WRITE);
#elif defined(RP2040_PLATFORM)
return _fs->open(filename, "w");
#else
return _fs->open(filename, "w", true);
#endif
}
void SensorMesh::loadContacts() {
num_contacts = 0;
if (_fs->exists("/s_contacts")) {
#if defined(RP2040_PLATFORM)
File file = _fs->open("/s_contacts", "r");
#else
File file = _fs->open("/s_contacts");
#endif
if (file) {
bool full = false;
while (!full) {
ContactInfo c;
uint8_t pub_key[32];
uint8_t unused;
bool success = (file.read(pub_key, 32) == 32);
success = success && (file.read(&c.type, 1) == 1);
success = success && (file.read(&c.flags, 1) == 1);
success = success && (file.read(&unused, 1) == 1);
success = success && (file.read((uint8_t *)&c.out_path_len, 1) == 1);
success = success && (file.read(c.out_path, 64) == 64);
success = success && (file.read(c.shared_secret, PUB_KEY_SIZE) == PUB_KEY_SIZE);
c.last_timestamp = 0; // transient
c.last_activity = 0;
if (!success) break; // EOF
c.id = mesh::Identity(pub_key);
if (num_contacts < MAX_CONTACTS) {
contacts[num_contacts++] = c;
} else {
full = true;
}
}
file.close();
}
}
}
void SensorMesh::saveContacts() {
File file = openWrite(_fs, "/s_contacts");
if (file) {
uint8_t unused = 0;
for (int i = 0; i < num_contacts; i++) {
auto c = &contacts[i];
if (c->type == 0) continue; // don't persist guest contacts
bool success = (file.write(c->id.pub_key, 32) == 32);
success = success && (file.write(&c->type, 1) == 1);
success = success && (file.write(&c->flags, 1) == 1);
success = success && (file.write(&unused, 1) == 1);
success = success && (file.write((uint8_t *)&c->out_path_len, 1) == 1);
success = success && (file.write(c->out_path, 64) == 64);
success = success && (file.write(c->shared_secret, PUB_KEY_SIZE) == PUB_KEY_SIZE);
if (!success) break; // write failed
}
file.close();
}
}
uint8_t SensorMesh::handleRequest(bool is_admin, uint32_t sender_timestamp, uint8_t req_type, uint8_t* payload, size_t payload_len) {
memcpy(reply_data, &sender_timestamp, 4); // reflect sender_timestamp back in response packet (kind of like a 'tag')
switch (req_type) {
case REQ_TYPE_GET_TELEMETRY_DATA: {
telemetry.reset();
telemetry.addVoltage(TELEM_CHANNEL_SELF, (float)board.getBattMilliVolts() / 1000.0f);
// query other sensors -- target specific
sensors.querySensors(0xFF, telemetry); // allow all telemetry permissions for admin or guest
uint8_t tlen = telemetry.getSize();
memcpy(&reply_data[4], telemetry.getBuffer(), tlen);
return 4 + tlen; // reply_len
}
}
return 0; // unknown command
}
mesh::Packet* SensorMesh::createSelfAdvert() {
uint8_t app_data[MAX_ADVERT_DATA_SIZE];
uint8_t app_data_len;
{
AdvertDataBuilder builder(ADV_TYPE_SENSOR, _prefs.node_name, _prefs.node_lat, _prefs.node_lon);
app_data_len = builder.encodeTo(app_data);
}
return createAdvert(self_id, app_data, app_data_len);
}
ContactInfo* SensorMesh::putContact(const mesh::Identity& id) {
uint32_t min_time = 0xFFFFFFFF;
ContactInfo* oldest = &contacts[MAX_CONTACTS - 1];
for (int i = 0; i < num_contacts; i++) {
if (id.matches(contacts[i].id)) return &contacts[i]; // already known
if (!contacts[i].isAdmin() && contacts[i].last_activity < min_time) {
oldest = &contacts[i];
min_time = oldest->last_activity;
}
}
ContactInfo* c;
if (num_contacts < MAX_CONTACTS) {
c = &contacts[num_contacts++];
} else {
c = oldest; // evict least active contact
}
memset(c, 0, sizeof(*c));
c->id = id;
c->out_path_len = -1; // initially out_path is unknown
return c;
}
void SensorMesh::alertIfLow(Trigger& t, float value, float threshold, const char* text) {
if (value < threshold) {
if (!t.triggered) {
t.triggered = true;
t.time = getRTCClock()->getCurrentTime();
sendAlert(text);
}
} else {
if (t.triggered) {
t.triggered = false;
// TODO: apply debounce logic
}
}
}
void SensorMesh::alertIfHigh(Trigger& t, float value, float threshold, const char* text) {
if (value > threshold) {
if (!t.triggered) {
t.triggered = true;
t.time = getRTCClock()->getCurrentTime();
sendAlert(text);
}
} else {
if (t.triggered) {
t.triggered = false;
// TODO: apply debounce logic
}
}
}
float SensorMesh::getAirtimeBudgetFactor() const {
return _prefs.airtime_factor;
}
bool SensorMesh::allowPacketForward(const mesh::Packet* packet) {
if (_prefs.disable_fwd) return false;
if (packet->isRouteFlood() && packet->path_len >= _prefs.flood_max) return false;
return true;
}
int SensorMesh::calcRxDelay(float score, uint32_t air_time) const {
if (_prefs.rx_delay_base <= 0.0f) return 0;
return (int) ((pow(_prefs.rx_delay_base, 0.85f - score) - 1.0) * air_time);
}
uint32_t SensorMesh::getRetransmitDelay(const mesh::Packet* packet) {
uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.tx_delay_factor);
return getRNG()->nextInt(0, 6)*t;
}
uint32_t SensorMesh::getDirectRetransmitDelay(const mesh::Packet* packet) {
uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
return getRNG()->nextInt(0, 6)*t;
}
int SensorMesh::getInterferenceThreshold() const {
return _prefs.interference_threshold;
}
int SensorMesh::getAGCResetInterval() const {
return ((int)_prefs.agc_reset_interval) * 4000; // milliseconds
}
uint8_t SensorMesh::handleLoginReq(const mesh::Identity& sender, const uint8_t* secret, uint32_t sender_timestamp, const uint8_t* data) {
bool is_admin;
if (strcmp((char *) data, _prefs.password) == 0) { // check for valid password
is_admin = true;
} else if (strcmp((char *) data, _prefs.guest_password) == 0) { // check guest password
is_admin = false;
} else {
#if MESH_DEBUG
MESH_DEBUG_PRINTLN("Invalid password: %s", &data[4]);
#endif
return 0;
}
auto client = putContact(sender); // add to contacts (if not already known)
if (sender_timestamp <= client->last_timestamp) {
MESH_DEBUG_PRINTLN("Possible login replay attack!");
return 0; // FATAL: client table is full -OR- replay attack
}
MESH_DEBUG_PRINTLN("Login success!");
client->last_timestamp = sender_timestamp;
client->last_activity = getRTCClock()->getCurrentTime();
client->type = is_admin ? 1 : 0;
memcpy(client->shared_secret, secret, PUB_KEY_SIZE);
if (is_admin) {
// only need to saveContacts() if this is an admin
dirty_contacts_expiry = futureMillis(LAZY_CONTACTS_WRITE_DELAY);
}
uint32_t now = getRTCClock()->getCurrentTimeUnique();
memcpy(reply_data, &now, 4); // response packets always prefixed with timestamp
reply_data[4] = RESP_SERVER_LOGIN_OK;
reply_data[5] = 0; // NEW: recommended keep-alive interval (secs / 16)
reply_data[6] = client->type;
reply_data[7] = 0; // FUTURE: reserved
getRNG()->random(&reply_data[8], 4); // random blob to help packet-hash uniqueness
return 12; // reply length
}
void SensorMesh::onAnonDataRecv(mesh::Packet* packet, const uint8_t* secret, const mesh::Identity& sender, uint8_t* data, size_t len) {
if (packet->getPayloadType() == PAYLOAD_TYPE_ANON_REQ) { // received an initial request by a possible admin client (unknown at this stage)
uint32_t timestamp;
memcpy(&timestamp, data, 4);
data[len] = 0; // ensure null terminator
uint8_t req_code;
uint8_t i = 4;
if (data[4] < 32) { // non-print char, is a request code
req_code = data[i++];
} else {
req_code = REQ_TYPE_LOGIN;
}
uint8_t reply_len;
if (req_code == REQ_TYPE_LOGIN) {
reply_len = handleLoginReq(sender, secret, timestamp, &data[i]);
} else {
reply_len = handleRequest(false, timestamp, req_code, &data[i], len - i);
}
if (reply_len == 0) return; // invalid request
if (packet->isRouteFlood()) {
// let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
mesh::Packet* path = createPathReturn(sender, secret, packet->path, packet->path_len,
PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
} else {
mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, sender, secret, reply_data, reply_len);
if (reply) sendFlood(reply, SERVER_RESPONSE_DELAY);
}
}
}
int SensorMesh::searchPeersByHash(const uint8_t* hash) {
int n = 0;
for (int i = 0; i < num_contacts && n < MAX_SEARCH_RESULTS; i++) {
if (contacts[i].id.isHashMatch(hash)) {
matching_peer_indexes[n++] = i; // store the INDEXES of matching contacts (for subsequent 'peer' methods)
}
}
return n;
}
void SensorMesh::getPeerSharedSecret(uint8_t* dest_secret, int peer_idx) {
int i = matching_peer_indexes[peer_idx];
if (i >= 0 && i < num_contacts) {
// lookup pre-calculated shared_secret
memcpy(dest_secret, contacts[i].shared_secret, PUB_KEY_SIZE);
} else {
MESH_DEBUG_PRINTLN("getPeerSharedSecret: Invalid peer idx: %d", i);
}
}
void SensorMesh::onAdvertRecv(mesh::Packet* packet, const mesh::Identity& id, uint32_t timestamp, const uint8_t* app_data, size_t app_data_len) {
mesh::Mesh::onAdvertRecv(packet, id, timestamp, app_data, app_data_len); // chain to super impl
#if 0
// if this a zero hop advert, add it to neighbours
if (packet->path_len == 0) {
AdvertDataParser parser(app_data, app_data_len);
if (parser.isValid() && parser.getType() == ADV_TYPE_REPEATER) { // just keep neigbouring Repeaters
putNeighbour(id, timestamp, packet->getSNR());
}
}
#endif
}
void SensorMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender_idx, const uint8_t* secret, uint8_t* data, size_t len) {
int i = matching_peer_indexes[sender_idx];
if (i < 0 || i >= num_contacts) {
MESH_DEBUG_PRINTLN("onPeerDataRecv: Invalid sender idx: %d", i);
return;
}
ContactInfo& from = contacts[i];
if (type == PAYLOAD_TYPE_REQ) { // request (from a known contact)
uint32_t timestamp;
memcpy(&timestamp, data, 4);
if (timestamp > from.last_timestamp) { // prevent replay attacks
uint8_t reply_len = handleRequest(from.isAdmin(), timestamp, data[4], &data[5], len - 5);
if (reply_len == 0) return; // invalid command
from.last_timestamp = timestamp;
from.last_activity = getRTCClock()->getCurrentTime();
if (packet->isRouteFlood()) {
// let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
mesh::Packet* path = createPathReturn(from.id, secret, packet->path, packet->path_len,
PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
} else {
mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, from.id, secret, reply_data, reply_len);
if (reply) {
if (from.out_path_len >= 0) { // we have an out_path, so send DIRECT
sendDirect(reply, from.out_path, from.out_path_len, SERVER_RESPONSE_DELAY);
} else {
sendFlood(reply, SERVER_RESPONSE_DELAY);
}
}
}
} else {
MESH_DEBUG_PRINTLN("onPeerDataRecv: possible replay attack detected");
}
} else if (type == PAYLOAD_TYPE_TXT_MSG && len > 5 && from.isAdmin()) { // a CLI command
uint32_t sender_timestamp;
memcpy(&sender_timestamp, data, 4); // timestamp (by sender's RTC clock - which could be wrong)
uint flags = (data[4] >> 2); // message attempt number, and other flags
if (!(flags == TXT_TYPE_CLI_DATA)) {
MESH_DEBUG_PRINTLN("onPeerDataRecv: unsupported text type received: flags=%02x", (uint32_t)flags);
} else if (sender_timestamp > from.last_timestamp) { // prevent replay attacks
from.last_timestamp = sender_timestamp;
from.last_activity = getRTCClock()->getCurrentTime();
// len can be > original length, but 'text' will be padded with zeroes
data[len] = 0; // need to make a C string again, with null terminator
uint8_t temp[166];
const char *command = (const char *) &data[5];
char *reply = (char *) &temp[5];
_cli.handleCommand(sender_timestamp, command, reply);
int text_len = strlen(reply);
if (text_len > 0) {
uint32_t timestamp = getRTCClock()->getCurrentTimeUnique();
if (timestamp == sender_timestamp) {
// WORKAROUND: the two timestamps need to be different, in the CLI view
timestamp++;
}
memcpy(temp, &timestamp, 4); // mostly an extra blob to help make packet_hash unique
temp[4] = (TXT_TYPE_CLI_DATA << 2);
auto reply = createDatagram(PAYLOAD_TYPE_TXT_MSG, from.id, secret, temp, 5 + text_len);
if (reply) {
if (from.out_path_len < 0) {
sendFlood(reply, CLI_REPLY_DELAY_MILLIS);
} else {
sendDirect(reply, from.out_path, from.out_path_len, CLI_REPLY_DELAY_MILLIS);
}
}
}
} else {
MESH_DEBUG_PRINTLN("onPeerDataRecv: possible replay attack detected");
}
}
}
bool SensorMesh::onPeerPathRecv(mesh::Packet* packet, int sender_idx, const uint8_t* secret, uint8_t* path, uint8_t path_len, uint8_t extra_type, uint8_t* extra, uint8_t extra_len) {
int i = matching_peer_indexes[sender_idx];
if (i < 0 || i >= num_contacts) {
MESH_DEBUG_PRINTLN("onPeerPathRecv: Invalid sender idx: %d", i);
return false;
}
ContactInfo& from = contacts[i];
MESH_DEBUG_PRINTLN("PATH to contact, path_len=%d", (uint32_t) path_len);
// NOTE: for this impl, we just replace the current 'out_path' regardless, whenever sender sends us a new out_path.
// FUTURE: could store multiple out_paths per contact, and try to find which is the 'best'(?)
memcpy(from.out_path, path, from.out_path_len = path_len); // store a copy of path, for sendDirect()
from.last_activity = getRTCClock()->getCurrentTime();
if (from.isAdmin()) {
// only need to saveContacts() if this is an admin
dirty_contacts_expiry = futureMillis(LAZY_CONTACTS_WRITE_DELAY);
}
// NOTE: no reciprocal path send!!
return false;
}
SensorMesh::SensorMesh(mesh::MainBoard& board, mesh::Radio& radio, mesh::MillisecondClock& ms, mesh::RNG& rng, mesh::RTCClock& rtc, mesh::MeshTables& tables)
: mesh::Mesh(radio, ms, rng, rtc, *new StaticPoolPacketManager(32), tables),
_cli(board, rtc, &_prefs, this), telemetry(MAX_PACKET_PAYLOAD - 4)
{
num_contacts = 0;
next_local_advert = next_flood_advert = 0;
dirty_contacts_expiry = 0;
last_read_time = 0;
// defaults
memset(&_prefs, 0, sizeof(_prefs));
_prefs.airtime_factor = 1.0; // one half
_prefs.rx_delay_base = 0.0f; // turn off by default, was 10.0;
_prefs.tx_delay_factor = 0.5f; // was 0.25f
StrHelper::strncpy(_prefs.node_name, ADVERT_NAME, sizeof(_prefs.node_name));
_prefs.node_lat = ADVERT_LAT;
_prefs.node_lon = ADVERT_LON;
StrHelper::strncpy(_prefs.password, ADMIN_PASSWORD, sizeof(_prefs.password));
_prefs.freq = LORA_FREQ;
_prefs.sf = LORA_SF;
_prefs.bw = LORA_BW;
_prefs.cr = LORA_CR;
_prefs.tx_power_dbm = LORA_TX_POWER;
_prefs.advert_interval = 1; // default to 2 minutes for NEW installs
_prefs.flood_advert_interval = 3; // 3 hours
_prefs.disable_fwd = true;
_prefs.flood_max = 64;
_prefs.interference_threshold = 0; // disabled
}
void SensorMesh::begin(FILESYSTEM* fs) {
mesh::Mesh::begin();
_fs = fs;
// load persisted prefs
_cli.loadPrefs(_fs);
loadContacts();
radio_set_params(_prefs.freq, _prefs.bw, _prefs.sf, _prefs.cr);
radio_set_tx_power(_prefs.tx_power_dbm);
updateAdvertTimer();
updateFloodAdvertTimer();
}
bool SensorMesh::formatFileSystem() {
#if defined(NRF52_PLATFORM) || defined(STM32_PLATFORM)
return InternalFS.format();
#elif defined(RP2040_PLATFORM)
return LittleFS.format();
#elif defined(ESP32)
return SPIFFS.format();
#else
#error "need to implement file system erase"
return false;
#endif
}
void SensorMesh::sendSelfAdvertisement(int delay_millis) {
mesh::Packet* pkt = createSelfAdvert();
if (pkt) {
sendFlood(pkt, delay_millis);
} else {
MESH_DEBUG_PRINTLN("ERROR: unable to create advertisement packet!");
}
}
void SensorMesh::updateAdvertTimer() {
if (_prefs.advert_interval > 0) { // schedule local advert timer
next_local_advert = futureMillis( ((uint32_t)_prefs.advert_interval) * 2 * 60 * 1000);
} else {
next_local_advert = 0; // stop the timer
}
}
void SensorMesh::updateFloodAdvertTimer() {
if (_prefs.flood_advert_interval > 0) { // schedule flood advert timer
next_flood_advert = futureMillis( ((uint32_t)_prefs.flood_advert_interval) * 60 * 60 * 1000);
} else {
next_flood_advert = 0; // stop the timer
}
}
void SensorMesh::setTxPower(uint8_t power_dbm) {
radio_set_tx_power(power_dbm);
}
void SensorMesh::loop() {
mesh::Mesh::loop();
if (next_flood_advert && millisHasNowPassed(next_flood_advert)) {
mesh::Packet* pkt = createSelfAdvert();
if (pkt) sendFlood(pkt);
updateFloodAdvertTimer(); // schedule next flood advert
updateAdvertTimer(); // also schedule local advert (so they don't overlap)
} else if (next_local_advert && millisHasNowPassed(next_local_advert)) {
mesh::Packet* pkt = createSelfAdvert();
if (pkt) sendZeroHop(pkt);
updateAdvertTimer(); // schedule next local advert
}
uint32_t curr = getRTCClock()->getCurrentTime();
if (curr >= last_read_time + SENSOR_READ_INTERVAL_SECS) {
telemetry.reset();
telemetry.addVoltage(TELEM_CHANNEL_SELF, (float)board.getBattMilliVolts() / 1000.0f);
// query other sensors -- target specific
sensors.querySensors(0xFF, telemetry); // allow all telemetry permissions
checkForAlerts();
// save telemetry to time-series datastore
File file = openAppend(_fs, "/s_data");
if (file) {
file.write((uint8_t *)&curr, 4); // start record with RTC timestamp
uint8_t tlen = telemetry.getSize();
file.write(&tlen, 1);
file.write(telemetry.getBuffer(), tlen);
uint8_t zero = 0;
while (tlen < MAX_PACKET_PAYLOAD - 4) { // pad with zeroes, for fixed record length
file.write(&zero, 1);
tlen++;
}
file.close();
}
last_read_time = curr;
}
// is there are pending dirty contacts write needed?
if (dirty_contacts_expiry && millisHasNowPassed(dirty_contacts_expiry)) {
saveContacts();
dirty_contacts_expiry = 0;
}
}
Reference in New Issue View Git Blame Copy Permalink