/* Tx callback for keepalive messages */
static void
keepalive_packet_sent(void *ptr, int status, int transmissions)
{
#ifdef TSCH_LINK_NEIGHBOR_CALLBACK
TSCH_LINK_NEIGHBOR_CALLBACK(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), status, transmissions);
#endif
PRINTF("TSCH: KA sent to %u, st %d-%d\n",
TSCH_LOG_ID_FROM_LINKADDR(packetbuf_addr(PACKETBUF_ADDR_RECEIVER)), status, transmissions);
tsch_schedule_keepalive();
}
/* Update TSCH time source */
int
tsch_queue_update_time_source(const linkaddr_t *new_addr)
{
if(!tsch_is_locked()) {
if(!tsch_is_coordinator) {
struct tsch_neighbor *old_time_src = tsch_queue_get_time_source();
struct tsch_neighbor *new_time_src = NULL;
if(new_addr != NULL) {
/* Get/add neighbor, return 0 in case of failure */
new_time_src = tsch_queue_add_nbr(new_addr);
if(new_time_src == NULL) {
return 0;
}
}
if(new_time_src != old_time_src) {
PRINTF("TSCH: update time source: %u -> %u\n",
TSCH_LOG_ID_FROM_LINKADDR(old_time_src ? &old_time_src->addr : NULL),
TSCH_LOG_ID_FROM_LINKADDR(new_time_src ? &new_time_src->addr : NULL));
/* Update time source */
if(new_time_src != NULL) {
new_time_src->is_time_source = 1;
/* (Re)set keep-alive timeout */
tsch_set_ka_timeout(TSCH_KEEPALIVE_TIMEOUT);
/* Start sending keepalives */
tsch_schedule_keepalive();
} else {
/* Stop sending keepalives */
tsch_set_ka_timeout(0);
}
if(old_time_src != NULL) {
old_time_src->is_time_source = 0;
}
#ifdef TSCH_CALLBACK_NEW_TIME_SOURCE
TSCH_CALLBACK_NEW_TIME_SOURCE(old_time_src, new_time_src);
#endif
}
return 1;
}
}
return 0;
}
/* Attempt to associate to a network form an incoming EB */
static int
tsch_associate(const struct input_packet *input_eb, rtimer_clock_t timestamp)
{
frame802154_t frame;
struct ieee802154_ies ies;
uint8_t hdrlen;
int i;
if(input_eb == NULL || tsch_packet_parse_eb(input_eb->payload, input_eb->len,
&frame, &ies, &hdrlen, 0) == 0) {
PRINTF("TSCH:! failed to parse EB (len %u)\n", input_eb->len);
return 0;
}
current_asn = ies.ie_asn;
tsch_join_priority = ies.ie_join_priority + 1;
#if TSCH_JOIN_SECURED_ONLY
if(frame.fcf.security_enabled == 0) {
PRINTF("TSCH:! parse_eb: EB is not secured\n");
return 0;
}
#endif /* TSCH_JOIN_SECURED_ONLY */
#if TSCH_SECURITY_ENABLED
if(!tsch_security_parse_frame(input_eb->payload, hdrlen,
input_eb->len - hdrlen - tsch_security_mic_len(&frame),
&frame, (linkaddr_t*)&frame.src_addr, ¤t_asn)) {
PRINTF("TSCH:! parse_eb: failed to authenticate\n");
return 0;
}
#endif /* TSCH_SECURITY_ENABLED */
#if !TSCH_SECURITY_ENABLED
if(frame.fcf.security_enabled == 1) {
PRINTF("TSCH:! parse_eb: we do not support security, but EB is secured\n");
return 0;
}
#endif /* !TSCH_SECURITY_ENABLED */
#if TSCH_JOIN_MY_PANID_ONLY
/* Check if the EB comes from the PAN ID we expect */
if(frame.src_pid != IEEE802154_PANID) {
PRINTF("TSCH:! parse_eb: PAN ID %x != %x\n", frame.src_pid, IEEE802154_PANID);
return 0;
}
#endif /* TSCH_JOIN_MY_PANID_ONLY */
/* There was no join priority (or 0xff) in the EB, do not join */
if(ies.ie_join_priority == 0xff) {
PRINTF("TSCH:! parse_eb: no join priority\n");
return 0;
}
/* TSCH timeslot timing */
for(i = 0; i < tsch_ts_elements_count; i++) {
if(ies.ie_tsch_timeslot_id == 0) {
tsch_timing[i] = US_TO_RTIMERTICKS(tsch_default_timing_us[i]);
} else {
tsch_timing[i] = US_TO_RTIMERTICKS(ies.ie_tsch_timeslot[i]);
}
}
/* TSCH hopping sequence */
if(ies.ie_channel_hopping_sequence_id == 0) {
memcpy(tsch_hopping_sequence, TSCH_DEFAULT_HOPPING_SEQUENCE, sizeof(TSCH_DEFAULT_HOPPING_SEQUENCE));
ASN_DIVISOR_INIT(tsch_hopping_sequence_length, sizeof(TSCH_DEFAULT_HOPPING_SEQUENCE));
} else {
if(ies.ie_hopping_sequence_len <= sizeof(tsch_hopping_sequence)) {
memcpy(tsch_hopping_sequence, ies.ie_hopping_sequence_list, ies.ie_hopping_sequence_len);
ASN_DIVISOR_INIT(tsch_hopping_sequence_length, ies.ie_hopping_sequence_len);
} else {
PRINTF("TSCH:! parse_eb: hopping sequence too long (%u)\n", ies.ie_hopping_sequence_len);
return 0;
}
}
#if TSCH_CHECK_TIME_AT_ASSOCIATION > 0
/* Divide by 4k and multiply again to avoid integer overflow */
uint32_t expected_asn = 4096 * TSCH_CLOCK_TO_SLOTS(clock_time() / 4096, tsch_timing_timeslot_length); /* Expected ASN based on our current time*/
int32_t asn_threshold = TSCH_CHECK_TIME_AT_ASSOCIATION * 60ul * TSCH_CLOCK_TO_SLOTS(CLOCK_SECOND, tsch_timing_timeslot_length);
int32_t asn_diff = (int32_t)current_asn.ls4b - expected_asn;
if(asn_diff > asn_threshold) {
PRINTF("TSCH:! EB ASN rejected %lx %lx %ld\n",
current_asn.ls4b, expected_asn, asn_diff);
return 0;
}
#endif
#if TSCH_INIT_SCHEDULE_FROM_EB
/* Create schedule */
if(ies.ie_tsch_slotframe_and_link.num_slotframes == 0) {
#if TSCH_SCHEDULE_WITH_6TISCH_MINIMAL
PRINTF("TSCH: parse_eb: no schedule, setting up minimal schedule\n");
tsch_schedule_create_minimal();
#else
PRINTF("TSCH: parse_eb: no schedule\n");
#endif
} else {
/* First, empty current schedule */
tsch_schedule_remove_all_slotframes();
/* We support only 0 or 1 slotframe in this IE */
int num_links = ies.ie_tsch_slotframe_and_link.num_links;
if(num_links <= FRAME802154E_IE_MAX_LINKS) {
int i;
struct tsch_slotframe *sf = tsch_schedule_add_slotframe(
ies.ie_tsch_slotframe_and_link.slotframe_handle,
ies.ie_tsch_slotframe_and_link.slotframe_size);
for(i = 0; i < num_links; i++) {
tsch_schedule_add_link(sf,
ies.ie_tsch_slotframe_and_link.links[i].link_options,
LINK_TYPE_ADVERTISING, &tsch_broadcast_address,
ies.ie_tsch_slotframe_and_link.links[i].timeslot, ies.ie_tsch_slotframe_and_link.links[i].channel_offset);
}
} else {
PRINTF("TSCH:! parse_eb: too many links in schedule (%u)\n", num_links);
return 0;
}
}
#endif /* TSCH_INIT_SCHEDULE_FROM_EB */
if(tsch_join_priority < TSCH_MAX_JOIN_PRIORITY) {
struct tsch_neighbor *n;
/* Add coordinator to list of neighbors, lock the entry */
n = tsch_queue_add_nbr((linkaddr_t *)&frame.src_addr);
if(n != NULL) {
tsch_queue_update_time_source((linkaddr_t *)&frame.src_addr);
#ifdef TSCH_CALLBACK_JOINING_NETWORK
TSCH_CALLBACK_JOINING_NETWORK();
#endif
/* Set PANID */
frame802154_set_pan_id(frame.src_pid);
/* Synchronize on EB */
tsch_slot_operation_sync(timestamp - tsch_timing[tsch_ts_tx_offset], ¤t_asn);
/* Update global flags */
tsch_is_associated = 1;
tsch_is_pan_secured = frame.fcf.security_enabled;
/* Association done, schedule keepalive messages */
tsch_schedule_keepalive();
PRINTF("TSCH: association done, sec %u, PAN ID %x, asn-%x.%lx, jp %u, timeslot id %u, hopping id %u, slotframe len %u with %u links, from ",
tsch_is_pan_secured,
frame.src_pid,
current_asn.ms1b, current_asn.ls4b, tsch_join_priority,
ies.ie_tsch_timeslot_id,
ies.ie_channel_hopping_sequence_id,
ies.ie_tsch_slotframe_and_link.slotframe_size,
ies.ie_tsch_slotframe_and_link.num_links);
PRINTLLADDR((const uip_lladdr_t *)&frame.src_addr);
PRINTF("\n");
return 1;
}
}
PRINTF("TSCH:! did not associate.\n");
return 0;
}