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/*
* Copyright (C) 2014 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup nhdp
* @{
*
* @file
* @brief Interface Information Base implementation for NHDP
*
* @author Fabian Nack <nack@inf.fu-berlin.de>
*
* @}
*/
#include "mutex.h"
#include "timex.h"
#include "xtimer.h"
#include "utlist.h"
#include "kernel_types.h"
#include "rfc5444/rfc5444.h"
#include "rfc5444/rfc5444_iana.h"
#include "rfc5444/rfc5444_writer.h"
#include "iib_table.h"
#include "nhdp_address.h"
#include "nhdp_metric.h"
#include "nhdp_writer.h"
#define ENABLE_DEBUG (0)
#include "debug.h"
/* Internal variables */
static mutex_t mtx_iib_access = MUTEX_INIT;
static iib_base_entry_t *iib_base_entry_head = NULL;
#if (NHDP_METRIC == NHDP_LMT_DAT)
static const double const_dat = (((double)DAT_CONSTANT) / DAT_MAXIMUM_LOSS);
#endif
/* Internal function prototypes */
static void rem_link_set_entry(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry);
static void cleanup_link_sets(void);
static iib_link_set_entry_t *add_default_link_set_entry(iib_base_entry_t *base_entry, timex_t *now,
uint64_t val_time);
static void reset_link_set_entry(iib_link_set_entry_t *ls_entry, timex_t *now, uint64_t val_time);
static iib_link_set_entry_t *update_link_set(iib_base_entry_t *base_entry, nib_entry_t *nb_elt,
timex_t *now, uint64_t val_time,
uint8_t sym, uint8_t lost);
static void release_link_tuple_addresses(iib_link_set_entry_t *ls_entry);
static int update_two_hop_set(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry,
timex_t *now, uint64_t val_time);
static int add_two_hop_entry(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry,
nhdp_addr_t *th_addr, timex_t *now, uint64_t val_time);
static void rem_two_hop_entry(iib_base_entry_t *base_entry, iib_two_hop_set_entry_t *th_entry);
static void wr_update_ls_status(iib_base_entry_t *base_entry,
iib_link_set_entry_t *ls_elt, timex_t *now);
static void update_nb_tuple_symmetry(iib_base_entry_t *base_entry,
iib_link_set_entry_t *ls_entry, timex_t *now);
static void rem_not_heard_nb_tuple(iib_link_set_entry_t *ls_entry, timex_t *now);
static inline timex_t get_max_timex(timex_t time_one, timex_t time_two);
static iib_link_tuple_status_t get_tuple_status(iib_link_set_entry_t *ls_entry, timex_t *now);
#if (NHDP_METRIC == NHDP_LMT_DAT)
static void queue_rem(uint8_t *queue);
static uint16_t queue_sum(uint8_t *queue);
static void dat_metric_refresh(void);
#endif
/*---------------------------------------------------------------------------*
* Interface Information Base API *
*---------------------------------------------------------------------------*/
int iib_register_if(kernel_pid_t pid)
{
iib_base_entry_t *new_entry = (iib_base_entry_t *) malloc(sizeof(iib_base_entry_t));
if (!new_entry) {
/* Insufficient memory */
return -1;
}
new_entry->if_pid = pid;
new_entry->link_set_head = NULL;
new_entry->two_hop_set_head = NULL;
LL_PREPEND(iib_base_entry_head, new_entry);
return 0;
}
iib_link_set_entry_t *iib_process_hello(kernel_pid_t if_pid, nib_entry_t *nb_elt,
uint64_t validity_time, uint8_t is_sym_nb,
uint8_t is_lost)
{
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_entry = NULL;
timex_t now;
mutex_lock(&mtx_iib_access);
/* Remove link tuple addresses that are included in the Removed Addr List */
cleanup_link_sets();
LL_FOREACH(iib_base_entry_head, base_elt) {
/* Find the link set and two hop set for the interface */
if (base_elt->if_pid == if_pid) {
break;
}
}
if (base_elt) {
xtimer_now_timex(&now);
/* Create a new link tuple for the neighbor that originated the hello */
ls_entry = update_link_set(base_elt, nb_elt, &now, validity_time, is_sym_nb, is_lost);
/* Create new two hop tuples for signaled symmetric neighbors */
if (ls_entry) {
update_two_hop_set(base_elt, ls_entry, &now, validity_time);
}
}
mutex_unlock(&mtx_iib_access);
return ls_entry;
}
void iib_fill_wr_addresses(kernel_pid_t if_pid, struct rfc5444_writer *wr)
{
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_elt;
nhdp_addr_entry_t *addr_elt;
timex_t now;
mutex_lock(&mtx_iib_access);
xtimer_now_timex(&now);
/* Before adding addresses first update the status of all link tuples */
iib_update_lt_status(&now);
/* Add all addresses of Link Tuples of the given interface's Link Set to the current HELLO */
LL_FOREACH(iib_base_entry_head, base_elt) {
if (base_elt->if_pid == if_pid) {
LL_FOREACH(base_elt->link_set_head, ls_elt) {
if (ls_elt->last_status != IIB_LT_STATUS_PENDING) {
/* Exclude addresses from tuples with L_STATUS = PENDING */
LL_FOREACH(ls_elt->address_list_head, addr_elt) {
if (!NHDP_ADDR_TMP_IN_ANY(addr_elt->address)) {
/* Add address to the writers next packet */
switch (ls_elt->last_status) {
case IIB_LT_STATUS_SYM:
nhdp_writer_add_addr(wr, addr_elt->address,
RFC5444_ADDRTLV_LINK_STATUS,
RFC5444_LINKSTATUS_SYMMETRIC,
rfc5444_metric_encode(ls_elt->metric_in),
rfc5444_metric_encode(ls_elt->metric_out));
addr_elt->address->in_tmp_table = NHDP_ADDR_TMP_SYM;
break;
case IIB_LT_STATUS_HEARD:
nhdp_writer_add_addr(wr, addr_elt->address,
RFC5444_ADDRTLV_LINK_STATUS,
RFC5444_LINKSTATUS_HEARD,
rfc5444_metric_encode(ls_elt->metric_in),
rfc5444_metric_encode(ls_elt->metric_out));
addr_elt->address->in_tmp_table = NHDP_ADDR_TMP_ANY;
break;
case IIB_LT_STATUS_UNKNOWN:
/* Fall through */
case IIB_LT_STATUS_LOST:
nhdp_writer_add_addr(wr, addr_elt->address,
RFC5444_ADDRTLV_LINK_STATUS,
RFC5444_LINKSTATUS_LOST,
rfc5444_metric_encode(ls_elt->metric_in),
rfc5444_metric_encode(ls_elt->metric_out));
addr_elt->address->in_tmp_table = NHDP_ADDR_TMP_ANY;
break;
case IIB_LT_STATUS_PENDING:
/* Pending link tuples are not included */
break;
default:
/* Should not happen */
DEBUG("%s:%d in %s: [WARNING] Unknown link tuple status\n",
RIOT_FILE_RELATIVE, __LINE__, DEBUG_FUNC);
break;
}
}
}
}
}
/* IF's link set found */
break;
}
}
mutex_unlock(&mtx_iib_access);
}
void iib_update_lt_status(timex_t *now)
{
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_elt, *ls_tmp;
LL_FOREACH(iib_base_entry_head, base_elt) {
LL_FOREACH_SAFE(base_elt->link_set_head, ls_elt, ls_tmp) {
wr_update_ls_status(base_elt, ls_elt, now);
}
}
}
void iib_propagate_nb_entry_change(nib_entry_t *old_entry, nib_entry_t *new_entry)
{
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_elt;
LL_FOREACH(iib_base_entry_head, base_elt) {
LL_FOREACH(base_elt->link_set_head, ls_elt) {
if (ls_elt->nb_elt == old_entry) {
ls_elt->nb_elt = new_entry;
}
}
}
}
void iib_process_metric_msg(iib_link_set_entry_t *ls_entry, uint64_t int_time)
{
#if (NHDP_METRIC == NHDP_LMT_HOP_COUNT)
/* Hop metric value for an existing direct link is always 1 */
(void)int_time;
ls_entry->metric_in = 1;
ls_entry->metric_out = 1;
if (ls_entry->nb_elt) {
ls_entry->nb_elt->metric_in = 1;
ls_entry->nb_elt->metric_out = 1;
}
#elif (NHDP_METRIC == NHDP_LMT_DAT)
/* Process required DAT metric steps */
ls_entry->hello_interval = rfc5444_timetlv_encode(int_time);
if (ls_entry->last_seq_no == 0) {
timex_t now, i_time;
xtimer_now_timex(&now);
i_time = timex_from_uint64(int_time * US_PER_MS * DAT_HELLO_TIMEOUT_FACTOR);
ls_entry->dat_received[0]++;
ls_entry->dat_total[0]++;
ls_entry->dat_time = timex_add(now, i_time);
}
#else
/* NHDP_METRIC is not set properly */
(void)ls_entry;
(void)int_time;
DEBUG("%s:%d in %s: [WARNING] Unknown NHDP_METRIC setting\n",
RIOT_FILE_RELATIVE, __LINE__, DEBUG_FUNC);
#endif
}
void iib_process_metric_pckt(iib_link_set_entry_t *ls_entry, uint32_t metric_out, uint16_t seq_no)
{
#if (NHDP_METRIC == NHDP_LMT_HOP_COUNT)
/* Nothing to do here */
(void)ls_entry;
(void)metric_out;
(void)seq_no;
#elif (NHDP_METRIC == NHDP_LMT_DAT)
/* Metric packet processing */
if (ls_entry->last_seq_no == 0) {
ls_entry->dat_received[0] = 1;
ls_entry->dat_total[0] = 1;
}
/* Don't add values to the queue for duplicate packets */
else if (seq_no != ls_entry->last_seq_no) {
uint16_t seq_diff;
if (seq_no < ls_entry->last_seq_no) {
seq_diff = (uint16_t) ((((uint32_t) seq_no) + 0xFFFF) - ls_entry->last_seq_no);
}
else {
seq_diff = seq_no - ls_entry->last_seq_no;
}
ls_entry->dat_total[0] += (seq_diff > NHDP_SEQNO_RESTART_DETECT) ? 1 : seq_diff;
ls_entry->dat_received[0]++;
}
ls_entry->last_seq_no = seq_no;
ls_entry->lost_hellos = 0;
if (ls_entry->hello_interval != 0) {
timex_t now, i_time;
xtimer_now_timex(&now);
i_time = timex_from_uint64(rfc5444_timetlv_decode(ls_entry->hello_interval)
* US_PER_MS * DAT_HELLO_TIMEOUT_FACTOR);
ls_entry->dat_time = timex_add(now, i_time);
}
/* Refresh metric value for link tuple and corresponding neighbor tuple */
if (ls_entry->nb_elt) {
if ((metric_out <= ls_entry->nb_elt->metric_out) ||
(ls_entry->nb_elt->metric_out == NHDP_METRIC_UNKNOWN)) {
/* Better value, use it also for your neighbor */
ls_entry->nb_elt->metric_out = metric_out;
}
else if (ls_entry->metric_out == ls_entry->nb_elt->metric_out){
/* The corresponding neighbor tuples metric needs to be updated */
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_elt;
ls_entry->nb_elt->metric_out = metric_out;
LL_FOREACH(iib_base_entry_head, base_elt) {
LL_FOREACH(base_elt->link_set_head, ls_elt) {
if ((ls_elt->nb_elt == ls_entry->nb_elt) && (ls_elt != ls_entry)) {
if (ls_elt->metric_out < ls_entry->nb_elt->metric_out) {
/* Smaller DAT value is better */
ls_entry->nb_elt->metric_out = ls_elt->metric_out;
}
break;
}
}
}
}
}
ls_entry->metric_out = metric_out;
#else
/* NHDP_METRIC is not set properly */
(void)ls_entry;
(void)metric_out;
(void)seq_no;
DEBUG("%s:%d in %s: [WARNING] Unknown NHDP_METRIC setting\n",
RIOT_FILE_RELATIVE, __LINE__, DEBUG_FUNC);
#endif
}
void iib_process_metric_refresh(void)
{
#if (NHDP_METRIC == NHDP_LMT_HOP_COUNT)
/* Nothing to do here */
#elif (NHDP_METRIC == NHDP_LMT_DAT)
dat_metric_refresh();
#else
/* NHDP_METRIC is not set properly */
DEBUG("%s:%d in %s: [WARNING] Unknown NHDP_METRIC setting\n",
RIOT_FILE_RELATIVE, __LINE__, DEBUG_FUNC);
#endif
}
/*------------------------------------------------------------------------------------*/
/* Internal functions */
/*------------------------------------------------------------------------------------*/
/**
* Remove addresses included in the Removed Address List from all existing Link Tuples
*/
static void cleanup_link_sets(void)
{
iib_base_entry_t *base_elt;
/* Loop through all link sets */
LL_FOREACH(iib_base_entry_head, base_elt) {
/* Loop through all link tuples of the link set */
iib_link_set_entry_t *ls_elt, *ls_tmp;
LL_FOREACH_SAFE(base_elt->link_set_head, ls_elt, ls_tmp) {
/* Loop through all addresses of the link tuples */
nhdp_addr_entry_t *lt_elt, *lt_tmp;
LL_FOREACH_SAFE(ls_elt->address_list_head, lt_elt, lt_tmp) {
if (NHDP_ADDR_TMP_IN_REM_LIST(lt_elt->address)) {
/* Remove link tuple address if included in the Removed Addr List */
LL_DELETE(ls_elt->address_list_head, lt_elt);
nhdp_free_addr_entry(lt_elt);
}
}
/* Remove link tuples with empty address list */
if (!ls_elt->address_list_head) {
if (ls_elt->last_status == IIB_LT_STATUS_SYM) {
/* Remove all two hop entries for the corresponding link tuple */
iib_two_hop_set_entry_t *th_elt, *th_tmp;
LL_FOREACH_SAFE(base_elt->two_hop_set_head, th_elt, th_tmp) {
if (th_elt->ls_elt == ls_elt) {
rem_two_hop_entry(base_elt, th_elt);
}
}
}
rem_link_set_entry(base_elt, ls_elt);
}
}
}
}
/**
* Update the Link Set for the receiving interface during HELLO message processing
*/
static iib_link_set_entry_t *update_link_set(iib_base_entry_t *base_entry, nib_entry_t *nb_elt,
timex_t *now, uint64_t val_time,
uint8_t sym, uint8_t lost)
{
iib_link_set_entry_t *ls_elt, *ls_tmp;
iib_link_set_entry_t *matching_lt = NULL;
nhdp_addr_entry_t *lt_elt;
timex_t v_time, l_hold;
uint8_t matches = 0;
/* Loop through every link tuple of the interface to update the link set */
LL_FOREACH_SAFE(base_entry->link_set_head, ls_elt, ls_tmp) {
/* Loop through all addresses of the link tuple */
LL_FOREACH(ls_elt->address_list_head, lt_elt) {
if (NHDP_ADDR_TMP_IN_SEND_LIST(lt_elt->address)) {
/* If link tuple address matches a sending addr we found a fitting tuple */
matches++;
if (matches > 1) {
/* Multiple matching link tuples, delete the previous one */
if (matching_lt->last_status == IIB_LT_STATUS_SYM) {
update_nb_tuple_symmetry(base_entry, matching_lt, now);
}
rem_link_set_entry(base_entry, matching_lt);
}
matching_lt = ls_elt;
break;
}
}
}
if (matches > 1) {
/* Multiple matching link tuples, reset the last one for reuse */
if (matching_lt->last_status == IIB_LT_STATUS_SYM) {
update_nb_tuple_symmetry(base_entry, matching_lt, now);
}
reset_link_set_entry(matching_lt, now, val_time);
}
else if (matches == 1) {
/* A single matching link tuple, only release the address list */
release_link_tuple_addresses(matching_lt);
}
else {
/* No single matching link tuple existant, create a new one */
matching_lt = add_default_link_set_entry(base_entry, now, val_time);
if (!matching_lt) {
/* Insufficient memory */
return NULL;
}
}
v_time = timex_from_uint64(val_time * US_PER_MS);
l_hold = timex_from_uint64(((uint64_t)NHDP_L_HOLD_TIME_MS) * US_PER_MS);
/* Set Sending Address List as this tuples address list */
matching_lt->address_list_head = nhdp_generate_addr_list_from_tmp(NHDP_ADDR_TMP_SEND_LIST);
if (!matching_lt->address_list_head) {
/* Insufficient memory */
rem_link_set_entry(base_entry, matching_lt);
return NULL;
}
matching_lt->nb_elt = nb_elt;
/* Set values dependent on link status */
if (sym) {
if (matching_lt->last_status != IIB_LT_STATUS_SYM) {
/* Set corresponding neighbor tuple to symmetric (Section 13.1 of RFC 6130) */
if (matching_lt->nb_elt) {
nib_set_nb_entry_sym(matching_lt->nb_elt);
}
}
matching_lt->sym_time = timex_add(*now, v_time);
matching_lt->last_status = IIB_LT_STATUS_SYM;
}
else if (lost) {
matching_lt->sym_time.microseconds = 0;
matching_lt->sym_time.seconds = 0;
if (matching_lt->last_status == IIB_LT_STATUS_SYM) {
update_nb_tuple_symmetry(base_entry, matching_lt, now);
}
if (get_tuple_status(matching_lt, now) == IIB_LT_STATUS_HEARD) {
matching_lt->last_status = IIB_LT_STATUS_HEARD;
matching_lt->exp_time = timex_add(*now, l_hold);
}
else {
matching_lt->last_status = IIB_LT_STATUS_UNKNOWN;
}
}
/* Set time values */
matching_lt->heard_time = get_max_timex(timex_add(*now, v_time), matching_lt->sym_time);
if (matching_lt->pending) {
/* L_status is PENDING */
matching_lt->exp_time = get_max_timex(matching_lt->exp_time, matching_lt->heard_time);
}
else if (!matching_lt->lost) {
if ((timex_cmp(matching_lt->sym_time, *now) == 1)
|| (timex_cmp(matching_lt->heard_time, *now) == 1)) {
/* L_status is HEARD or SYMMETRIC */
matching_lt->exp_time = get_max_timex(matching_lt->exp_time,
timex_add(matching_lt->heard_time, l_hold));
}
}
return matching_lt;
}
/**
* Update the status of a link tuple and process necessary changes and execute
* necessary changes in the 2-Hop Set and in the Neighbor Information Base
* Implements logic of Section 13 of RFC 6130
*/
static void wr_update_ls_status(iib_base_entry_t *base_entry,
iib_link_set_entry_t *ls_elt, timex_t *now)
{
if (timex_cmp(ls_elt->exp_time, *now) != 1) {
/* Entry expired and has to be removed */
if (ls_elt->last_status == IIB_LT_STATUS_SYM) {
update_nb_tuple_symmetry(base_entry, ls_elt, now);
}
rem_not_heard_nb_tuple(ls_elt, now);
rem_link_set_entry(base_entry, ls_elt);
}
else if ((ls_elt->last_status == IIB_LT_STATUS_SYM)
&& (timex_cmp(ls_elt->sym_time, *now) != 1)) {
/* Status changed from SYMMETRIC to HEARD */
update_nb_tuple_symmetry(base_entry, ls_elt, now);
ls_elt->last_status = IIB_LT_STATUS_HEARD;
if (timex_cmp(ls_elt->heard_time, *now) != 1) {
/* New status is LOST (equals IIB_LT_STATUS_UNKNOWN) */
rem_not_heard_nb_tuple(ls_elt, now);
ls_elt->nb_elt = NULL;
ls_elt->last_status = IIB_LT_STATUS_UNKNOWN;
}
}
else if ((ls_elt->last_status == IIB_LT_STATUS_HEARD)
&& (timex_cmp(ls_elt->heard_time, *now) != 1)) {
/* Status changed from HEARD to LOST (equals IIB_LT_STATUS_UNKNOWN) */
rem_not_heard_nb_tuple(ls_elt, now);
ls_elt->nb_elt = NULL;
ls_elt->last_status = IIB_LT_STATUS_UNKNOWN;
}
}
/**
* Add a new Link Tuple with default values to the given Link Set
*/
static iib_link_set_entry_t *add_default_link_set_entry(iib_base_entry_t *base_entry, timex_t *now,
uint64_t val_time)
{
iib_link_set_entry_t *new_entry;
new_entry = (iib_link_set_entry_t *) malloc(sizeof(iib_link_set_entry_t));
if (!new_entry) {
/* Insufficient memory */
return NULL;
}
new_entry->address_list_head = NULL;
reset_link_set_entry(new_entry, now, val_time);
LL_PREPEND(base_entry->link_set_head, new_entry);
return new_entry;
}
/**
* Reset a given Link Tuple for reusage
*/
static void reset_link_set_entry(iib_link_set_entry_t *ls_entry, timex_t *now, uint64_t val_time)
{
timex_t v_time = timex_from_uint64(val_time * US_PER_MS);
release_link_tuple_addresses(ls_entry);
ls_entry->sym_time.microseconds = 0;
ls_entry->sym_time.seconds = 0;
ls_entry->heard_time.microseconds = 0;
ls_entry->heard_time.seconds = 0;
ls_entry->pending = NHDP_INITIAL_PENDING;
ls_entry->lost = 0;
ls_entry->exp_time = timex_add(*now, v_time);
ls_entry->nb_elt = NULL;
ls_entry->last_status = IIB_LT_STATUS_UNKNOWN;
ls_entry->metric_in = NHDP_METRIC_UNKNOWN;
ls_entry->metric_out = NHDP_METRIC_UNKNOWN;
#if (NHDP_METRIC == NHDP_LMT_DAT)
memset(ls_entry->dat_received, 0, NHDP_Q_MEM_LENGTH);
memset(ls_entry->dat_total, 0, NHDP_Q_MEM_LENGTH);
ls_entry->dat_time.microseconds = 0;
ls_entry->dat_time.seconds = 0;
ls_entry->hello_interval = 0;
ls_entry->lost_hellos = 0;
ls_entry->rx_bitrate = 100000;
ls_entry->last_seq_no = 0;
#endif
}
/**
* Remove a given Link Tuple
*/
static void rem_link_set_entry(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry)
{
LL_DELETE(base_entry->link_set_head, ls_entry);
release_link_tuple_addresses(ls_entry);
free(ls_entry);
}
/**
* Free all address entries of a link tuple
*/
static void release_link_tuple_addresses(iib_link_set_entry_t *ls_entry)
{
nhdp_free_addr_list(ls_entry->address_list_head);
ls_entry->address_list_head = NULL;
}
/**
* Update the 2-Hop Set during HELLO message processing
*/
static int update_two_hop_set(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry,
timex_t *now, uint64_t val_time)
{
/* Check whether a corresponding link tuple was created */
if (ls_entry == NULL) {
return -1;
}
/* If the link to the neighbor is still symmetric */
if (get_tuple_status(ls_entry, now) == IIB_LT_STATUS_SYM) {
iib_two_hop_set_entry_t *ths_elt, *ths_tmp;
nhdp_addr_t *addr_elt;
/* Loop through all the two hop tuples of the two hop set */
LL_FOREACH_SAFE(base_entry->two_hop_set_head, ths_elt, ths_tmp) {
if (timex_cmp(ths_elt->exp_time, *now) != 1) {
/* Entry is expired, remove it */
rem_two_hop_entry(base_entry, ths_elt);
}
else if (ths_elt->ls_elt == ls_entry) {
if (ths_elt->th_nb_addr->in_tmp_table &
(NHDP_ADDR_TMP_TH_REM_LIST | NHDP_ADDR_TMP_TH_SYM_LIST)) {
rem_two_hop_entry(base_entry, ths_elt);
}
}
}
/* Add a new entry for every signaled symmetric neighbor address */
LL_FOREACH(nhdp_get_addr_db_head(), addr_elt) {
if (NHDP_ADDR_TMP_IN_TH_SYM_LIST(addr_elt)) {
if (add_two_hop_entry(base_entry, ls_entry, addr_elt, now, val_time)) {
/* No more memory available, return error */
return -1;
}
}
}
}
return 0;
}
/**
* Add a 2-Hop Tuple for a given address
*/
static int add_two_hop_entry(iib_base_entry_t *base_entry, iib_link_set_entry_t *ls_entry,
nhdp_addr_t *th_addr, timex_t *now, uint64_t val_time)
{
iib_two_hop_set_entry_t *new_entry;
timex_t v_time = timex_from_uint64(val_time * US_PER_MS);
new_entry = (iib_two_hop_set_entry_t *) malloc(sizeof(iib_two_hop_set_entry_t));
if (!new_entry) {
/* Insufficient memory */
return -1;
}
/* Increment usage counter of address in central NHDP address storage */
th_addr->usg_count++;
new_entry->th_nb_addr = th_addr;
new_entry->ls_elt = ls_entry;
new_entry->exp_time = timex_add(*now, v_time);
if (th_addr->tmp_metric_val != NHDP_METRIC_UNKNOWN) {
new_entry->metric_in = rfc5444_metric_decode(th_addr->tmp_metric_val);
new_entry->metric_out = rfc5444_metric_decode(th_addr->tmp_metric_val);
}
else {
new_entry->metric_in = NHDP_METRIC_UNKNOWN;
new_entry->metric_out = NHDP_METRIC_UNKNOWN;
}
LL_PREPEND(base_entry->two_hop_set_head, new_entry);
return 0;
}
/**
* Remove a given 2-Hop Tuple
*/
static void rem_two_hop_entry(iib_base_entry_t *base_entry, iib_two_hop_set_entry_t *th_entry)
{
LL_DELETE(base_entry->two_hop_set_head, th_entry);
nhdp_decrement_addr_usage(th_entry->th_nb_addr);
free(th_entry);
}
/**
* Remove all corresponding two hop entries for a given link tuple that lost symmetry status.
* Additionally reset the neighbor tuple's symmmetry flag (for the neighbor tuple this link
* tuple is represented in), if no more corresponding symmetric link tuples are left.
* Implements section 13.2 of RFC 6130
*/
static void update_nb_tuple_symmetry(iib_base_entry_t *base_entry,
iib_link_set_entry_t *ls_entry, timex_t *now)
{
iib_two_hop_set_entry_t *th_elt, *th_tmp;
/* First remove all two hop entries for the corresponding link tuple */
LL_FOREACH_SAFE(base_entry->two_hop_set_head, th_elt, th_tmp) {
if (th_elt->ls_elt == ls_entry) {
rem_two_hop_entry(base_entry, th_elt);
}
}
/* Afterwards check the neighbor tuple containing the link tuple's addresses */
if ((ls_entry->nb_elt != NULL) && (ls_entry->nb_elt->symmetric == 1)) {
iib_base_entry_t *base_tmp;
LL_FOREACH(iib_base_entry_head, base_tmp) {
iib_link_set_entry_t *ls_tmp;
LL_FOREACH(base_tmp->link_set_head, ls_tmp) {
if ((ls_entry->nb_elt == ls_tmp->nb_elt) && (ls_entry != ls_tmp)) {
if (timex_cmp(ls_tmp->sym_time, *now) == 1) {
return;
}
}
}
}
/* No remaining symmetric link tuple for the neighbor tuple */
nib_reset_nb_entry_sym(ls_entry->nb_elt, now);
}
}
/**
* Remove a neighbor tuple if no more corresponding heard link tuples are left
* Implements section 13.3 of RFC 6130
*/
static void rem_not_heard_nb_tuple(iib_link_set_entry_t *ls_entry, timex_t *now)
{
/* Check whether the corresponding neighbor tuple still exists */
if (ls_entry->nb_elt) {
iib_base_entry_t *base_tmp;
LL_FOREACH(iib_base_entry_head, base_tmp) {
iib_link_set_entry_t *ls_tmp;
LL_FOREACH(base_tmp->link_set_head, ls_tmp) {
if ((ls_entry->nb_elt == ls_tmp->nb_elt) && (ls_entry != ls_tmp)) {
if (timex_cmp(ls_tmp->heard_time, *now) == 1) {
return;
}
ls_tmp->nb_elt = NULL;
}
}
}
/* No remaining heard link tuple for the neighbor tuple */
nib_rem_nb_entry(ls_entry->nb_elt);
}
}
/**
* Get the L_STATUS value of a given link tuple
*/
static iib_link_tuple_status_t get_tuple_status(iib_link_set_entry_t *ls_entry, timex_t *now)
{
if (ls_entry->pending) {
return IIB_LT_STATUS_PENDING;
}
else if (ls_entry->lost) {
return IIB_LT_STATUS_LOST;
}
else if (timex_cmp(ls_entry->sym_time, *now) == 1) {
return IIB_LT_STATUS_SYM;
}
else if (timex_cmp(ls_entry->heard_time, *now) == 1) {
return IIB_LT_STATUS_HEARD;
}
return IIB_LT_STATUS_UNKNOWN;
}
/**
* Get the later one of two timex representation
*/
static inline timex_t get_max_timex(timex_t time_one, timex_t time_two)
{
if (timex_cmp(time_one, time_two) != -1) {
return time_one;
}
return time_two;
}
#if (NHDP_METRIC == NHDP_LMT_DAT)
/**
* Sum all elements in the queue
*/
static uint16_t queue_sum(uint8_t *queue)
{
uint16_t sum = 0;
for (int i = 0; i < NHDP_Q_MEM_LENGTH; i++) {
sum += queue[i];
}
return sum;
}
/**
* Remove the oldest element in the queue
*/
static void queue_rem(uint8_t *queue)
{
uint8_t temp;
uint8_t prev_value = queue[0];
/* Clear spot for a new element */
queue[0] = 0;
/* Shift elements */
for (int i = 1; i < NHDP_Q_MEM_LENGTH; i++) {
temp = queue[i];
queue[i] = prev_value;
prev_value = temp;
}
}
/**
* Update DAT metric values for all Link Tuples
*/
static void dat_metric_refresh(void)
{
iib_base_entry_t *base_elt;
iib_link_set_entry_t *ls_elt;
uint32_t metric_temp;
double sum_total, sum_rcvd, loss;
LL_FOREACH(iib_base_entry_head, base_elt) {
LL_FOREACH(base_elt->link_set_head, ls_elt) {
sum_rcvd = queue_sum(ls_elt->dat_received);
sum_total = queue_sum(ls_elt->dat_total);
metric_temp = ls_elt->metric_in;
if ((ls_elt->hello_interval != 0) && (ls_elt->lost_hellos > 0)) {
/* Compute lost time proportion */
loss = (((double)ls_elt->hello_interval) * ((double)ls_elt->lost_hellos))
/ DAT_MEMORY_LENGTH;
if (loss >= 1.0) {
sum_rcvd = 0.0;
}
else {
sum_rcvd *= (1.0 - loss);
}
}
if (sum_rcvd < 1.0) {
ls_elt->metric_in = NHDP_METRIC_MAXIMUM;
}
else {
loss = sum_total / sum_rcvd;
if (loss > DAT_MAXIMUM_LOSS) {
loss = DAT_MAXIMUM_LOSS;
}
ls_elt->metric_in = (const_dat * loss) / (ls_elt->rx_bitrate / DAT_MINIMUM_BITRATE);
if (ls_elt->metric_in > NHDP_METRIC_MAXIMUM) {
ls_elt->metric_in = NHDP_METRIC_MAXIMUM;
}
}
if (ls_elt->nb_elt) {
if (ls_elt->metric_in <= ls_elt->nb_elt->metric_in ||
(ls_elt->nb_elt->metric_in == NHDP_METRIC_UNKNOWN)) {
/* Better value, use it also for your neighbor */
ls_elt->nb_elt->metric_in = ls_elt->metric_in;
}
else if (metric_temp == ls_elt->nb_elt->metric_in){
/* The corresponding neighbor tuples metric needs to be updated */
iib_base_entry_t *base_entry;
iib_link_set_entry_t *ls_entry;
ls_elt->nb_elt->metric_in = ls_elt->metric_in;
LL_FOREACH(iib_base_entry_head, base_entry) {
LL_FOREACH(base_entry->link_set_head, ls_entry) {
if ((ls_elt->nb_elt == ls_entry->nb_elt) && (ls_elt != ls_entry)) {
if (ls_entry->metric_in < ls_elt->nb_elt->metric_in) {
/* Smaller DAT value is better */
ls_elt->nb_elt->metric_in = ls_entry->metric_in;
}
break;
}
}
}
}
}
queue_rem(ls_elt->dat_received);
queue_rem(ls_elt->dat_total);
}
}
}
#endif