int sd_ipv4ll_set_mac(sd_ipv4ll *ll, const struct ether_addr *addr) {
bool need_restart = false;
assert_return(ll, -EINVAL);
assert_return(addr, -EINVAL);
if (memcmp(&ll->mac_addr, addr, ETH_ALEN) == 0)
return 0;
if (!IN_SET(ll->state, IPV4LL_STATE_INIT, IPV4LL_STATE_STOPPED)) {
log_ipv4ll(ll, "Changing MAC address on running IPv4LL "
"client, restarting");
ll = ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
need_restart = true;
}
if (!ll)
return 0;
memcpy(&ll->mac_addr, addr, ETH_ALEN);
if (need_restart)
sd_ipv4ll_start(ll);
return 0;
}
int sd_ipv4ll_stop(sd_ipv4ll *ll) {
ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
if (ll)
ipv4ll_set_state(ll, IPV4LL_STATE_STOPPED, 1);
return 0;
}
int sd_ipv4ll_start (sd_ipv4ll *ll) {
int r;
assert_return(ll, -EINVAL);
assert_return(ll->event, -EINVAL);
assert_return(ll->index > 0, -EINVAL);
assert_return(ll->state == IPV4LL_STATE_INIT, -EBUSY);
r = arp_network_bind_raw_socket(ll->index, &ll->link);
if (r < 0)
goto out;
ll->fd = r;
ll->conflict = 0;
ll->defend_window = 0;
ll->claimed_address = 0;
if (ll->address == 0)
ll->address = ipv4ll_pick_address(ll);
ipv4ll_set_state (ll, IPV4LL_STATE_INIT, 1);
r = sd_event_add_io(ll->event, &ll->receive_message, ll->fd,
EPOLLIN, ipv4ll_receive_message, ll);
if (r < 0)
goto out;
r = sd_event_source_set_priority(ll->receive_message, ll->event_priority);
if (r < 0)
goto out;
r = sd_event_add_monotonic(ll->event, &ll->timer, now(CLOCK_MONOTONIC), 0,
ipv4ll_timer, ll);
if (r < 0)
goto out;
r = sd_event_source_set_priority(ll->timer, ll->event_priority);
out:
if (r < 0)
ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
return 0;
}
int sd_ipv4ll_attach_event(sd_ipv4ll *ll, sd_event *event, int priority) {
int r;
assert_return(ll, -EINVAL);
assert_return(!ll->event, -EBUSY);
if (event)
ll->event = sd_event_ref(event);
else {
r = sd_event_default(&ll->event);
if (r < 0) {
ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
return r;
}
}
ll->event_priority = priority;
return 0;
}
int sd_ipv4ll_start (sd_ipv4ll *ll) {
int r;
assert_return(ll, -EINVAL);
assert_return(ll->event, -EINVAL);
assert_return(ll->index > 0, -EINVAL);
assert_return(IN_SET(ll->state, IPV4LL_STATE_INIT,
IPV4LL_STATE_STOPPED), -EBUSY);
ll->state = IPV4LL_STATE_INIT;
r = arp_network_bind_raw_socket(ll->index, &ll->link);
if (r < 0)
goto out;
ll->fd = r;
ll->conflict = 0;
ll->defend_window = 0;
ll->claimed_address = 0;
if (!ll->random_data) {
uint8_t seed[8];
/* Fallback to mac */
siphash24(seed, &ll->mac_addr.ether_addr_octet,
ETH_ALEN, HASH_KEY.bytes);
r = sd_ipv4ll_set_address_seed(ll, seed);
if (r < 0)
goto out;
}
if (ll->address == 0) {
r = ipv4ll_pick_address(ll, &ll->address);
if (r < 0)
goto out;
}
ipv4ll_set_state (ll, IPV4LL_STATE_INIT, 1);
r = sd_event_add_io(ll->event, &ll->receive_message, ll->fd,
EPOLLIN, ipv4ll_receive_message, ll);
if (r < 0)
goto out;
r = sd_event_source_set_priority(ll->receive_message, ll->event_priority);
if (r < 0)
goto out;
r = sd_event_source_set_description(ll->receive_message, "ipv4ll-receive-message");
if (r < 0)
goto out;
r = sd_event_add_time(ll->event,
&ll->timer,
clock_boottime_or_monotonic(),
now(clock_boottime_or_monotonic()), 0,
ipv4ll_timer, ll);
if (r < 0)
goto out;
r = sd_event_source_set_priority(ll->timer, ll->event_priority);
if (r < 0)
goto out;
r = sd_event_source_set_description(ll->timer, "ipv4ll-timer");
out:
if (r < 0)
ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
return 0;
}
static void ipv4ll_run_state_machine(sd_ipv4ll *ll, IPv4LLTrigger trigger, void *trigger_data) {
struct ether_arp out_packet;
int out_packet_ready = 0;
int r = 0;
assert(ll);
assert(trigger < _IPV4LL_TRIGGER_MAX);
if (ll->state == IPV4LL_STATE_INIT) {
log_ipv4ll(ll, "PROBE");
ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_PROBE, 1);
ipv4ll_set_next_wakeup(ll, 0, PROBE_WAIT);
} else if ((ll->state == IPV4LL_STATE_WAITING_PROBE && trigger == IPV4LL_TRIGGER_TIMEOUT) ||
(ll->state == IPV4LL_STATE_PROBING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration < PROBE_NUM-2)) {
/* Send a probe */
arp_packet_probe(&out_packet, ll->address, &ll->mac_addr);
out_packet_ready = 1;
ipv4ll_set_state(ll, IPV4LL_STATE_PROBING, 0);
ipv4ll_set_next_wakeup(ll, PROBE_MIN, (PROBE_MAX-PROBE_MIN));
} else if (ll->state == IPV4LL_STATE_PROBING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration >= PROBE_NUM-2) {
/* Send the last probe */
arp_packet_probe(&out_packet, ll->address, &ll->mac_addr);
out_packet_ready = 1;
ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_ANNOUNCE, 1);
ipv4ll_set_next_wakeup(ll, ANNOUNCE_WAIT, 0);
} else if ((ll->state == IPV4LL_STATE_WAITING_ANNOUNCE && trigger == IPV4LL_TRIGGER_TIMEOUT) ||
(ll->state == IPV4LL_STATE_ANNOUNCING && trigger == IPV4LL_TRIGGER_TIMEOUT && ll->iteration < ANNOUNCE_NUM-1)) {
/* Send announcement packet */
arp_packet_announcement(&out_packet, ll->address, &ll->mac_addr);
out_packet_ready = 1;
ipv4ll_set_state(ll, IPV4LL_STATE_ANNOUNCING, 0);
ipv4ll_set_next_wakeup(ll, ANNOUNCE_INTERVAL, 0);
if (ll->iteration == 0) {
log_ipv4ll(ll, "ANNOUNCE");
ll->claimed_address = ll->address;
ll = ipv4ll_client_notify(ll, IPV4LL_EVENT_BIND);
if (!ll || ll->state == IPV4LL_STATE_STOPPED)
goto out;
ll->conflict = 0;
}
} else if ((ll->state == IPV4LL_STATE_ANNOUNCING && trigger == IPV4LL_TRIGGER_TIMEOUT &&
ll->iteration >= ANNOUNCE_NUM-1)) {
ipv4ll_set_state(ll, IPV4LL_STATE_RUNNING, 0);
ll->next_wakeup_valid = 0;
} else if (trigger == IPV4LL_TRIGGER_PACKET) {
int conflicted = 0;
usec_t time_now;
struct ether_arp* in_packet = (struct ether_arp*)trigger_data;
assert(in_packet);
if (IN_SET(ll->state, IPV4LL_STATE_ANNOUNCING, IPV4LL_STATE_RUNNING)) {
if (ipv4ll_arp_conflict(ll, in_packet)) {
r = sd_event_now(ll->event, clock_boottime_or_monotonic(), &time_now);
if (r < 0)
goto out;
/* Defend address */
if (time_now > ll->defend_window) {
ll->defend_window = time_now + DEFEND_INTERVAL * USEC_PER_SEC;
arp_packet_announcement(&out_packet, ll->address, &ll->mac_addr);
out_packet_ready = 1;
} else
conflicted = 1;
}
} else if (IN_SET(ll->state, IPV4LL_STATE_WAITING_PROBE,
IPV4LL_STATE_PROBING,
IPV4LL_STATE_WAITING_ANNOUNCE)) {
conflicted = ipv4ll_arp_probe_conflict(ll, in_packet);
}
if (conflicted) {
log_ipv4ll(ll, "CONFLICT");
ll = ipv4ll_client_notify(ll, IPV4LL_EVENT_CONFLICT);
if (!ll || ll->state == IPV4LL_STATE_STOPPED)
goto out;
ll->claimed_address = 0;
/* Pick a new address */
r = ipv4ll_pick_address(ll, &ll->address);
if (r < 0)
goto out;
ll->conflict++;
ll->defend_window = 0;
ipv4ll_set_state(ll, IPV4LL_STATE_WAITING_PROBE, 1);
if (ll->conflict >= MAX_CONFLICTS) {
log_ipv4ll(ll, "MAX_CONFLICTS");
ipv4ll_set_next_wakeup(ll, RATE_LIMIT_INTERVAL, PROBE_WAIT);
} else
ipv4ll_set_next_wakeup(ll, 0, PROBE_WAIT);
}
}
if (out_packet_ready) {
r = arp_network_send_raw_socket(ll->fd, &ll->link, &out_packet);
if (r < 0) {
log_ipv4ll(ll, "failed to send arp packet out");
goto out;
}
}
if (ll->next_wakeup_valid) {
ll->timer = sd_event_source_unref(ll->timer);
r = sd_event_add_time(ll->event, &ll->timer, clock_boottime_or_monotonic(),
ll->next_wakeup, 0, ipv4ll_timer, ll);
if (r < 0)
goto out;
r = sd_event_source_set_priority(ll->timer, ll->event_priority);
if (r < 0)
goto out;
r = sd_event_source_set_description(ll->timer, "ipv4ll-timer");
if (r < 0)
goto out;
}
out:
if (r < 0 && ll)
ipv4ll_stop(ll, r);
}
int sd_ipv4ll_stop(sd_ipv4ll *ll) {
return ipv4ll_stop(ll, IPV4LL_EVENT_STOP);
}