#include "in-addr-util.h"
#include "ndisc-internal.h"
#include "ndisc-router.h"
+#include "random-util.h"
#include "socket-util.h"
#include "string-util.h"
#include "util.h"
-#define NDISC_ROUTER_SOLICITATION_INTERVAL (4U * USEC_PER_SEC)
-#define NDISC_MAX_ROUTER_SOLICITATIONS 3U
+#define NDISC_TIMEOUT_NO_RA_USEC (NDISC_ROUTER_SOLICITATION_INTERVAL * NDISC_MAX_ROUTER_SOLICITATIONS)
static void ndisc_callback(sd_ndisc *ndisc, sd_ndisc_event event, sd_ndisc_router *rt) {
assert(ndisc);
assert(nd);
nd->timeout_event_source = sd_event_source_unref(nd->timeout_event_source);
+ nd->timeout_no_ra = sd_event_source_unref(nd->timeout_no_ra);
+ nd->retransmit_time = 0;
nd->recv_event_source = sd_event_source_unref(nd->recv_event_source);
nd->fd = safe_close(nd->fd);
- nd->nd_sent = 0;
return 0;
}
return ndisc_handle_datagram(nd, rt);
}
+static usec_t ndisc_timeout_compute_random(usec_t val) {
+ /* compute a time that is random within ±10% of the given value */
+ return val - val / 10 +
+ (random_u64() % (2 * USEC_PER_SEC)) * val / 10 / USEC_PER_SEC;
+}
+
static int ndisc_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
sd_ndisc *nd = userdata;
- usec_t time_now, next_timeout;
+ usec_t time_now;
int r;
+ char time_string[FORMAT_TIMESPAN_MAX];
assert(s);
assert(nd);
assert(nd->event);
- if (nd->nd_sent >= NDISC_MAX_ROUTER_SOLICITATIONS) {
- nd->timeout_event_source = sd_event_source_unref(nd->timeout_event_source);
- ndisc_callback(nd, SD_NDISC_EVENT_TIMEOUT, NULL);
- return 0;
- }
-
r = icmp6_send_router_solicitation(nd->fd, &nd->mac_addr);
if (r < 0) {
log_ndisc_errno(r, "Error sending Router Solicitation: %m");
goto fail;
}
- log_ndisc("Sent Router Solicitation");
- nd->nd_sent++;
-
assert_se(sd_event_now(nd->event, clock_boottime_or_monotonic(), &time_now) >= 0);
- next_timeout = time_now + NDISC_ROUTER_SOLICITATION_INTERVAL;
- r = sd_event_source_set_time(nd->timeout_event_source, next_timeout);
- if (r < 0) {
- log_ndisc_errno(r, "Error updating timer: %m");
- goto fail;
+ nd->timeout_event_source = sd_event_source_unref(nd->timeout_event_source);
+
+ if (!nd->retransmit_time)
+ nd->retransmit_time = ndisc_timeout_compute_random(NDISC_ROUTER_SOLICITATION_INTERVAL);
+ else {
+ if (nd->retransmit_time > NDISC_MAX_ROUTER_SOLICITATION_INTERVAL / 2)
+ nd->retransmit_time = ndisc_timeout_compute_random(NDISC_MAX_ROUTER_SOLICITATION_INTERVAL);
+ else
+ nd->retransmit_time += ndisc_timeout_compute_random(nd->retransmit_time);
}
+ r = sd_event_add_time(nd->event, &nd->timeout_event_source,
+ clock_boottime_or_monotonic(),
+ time_now + nd->retransmit_time,
+ 10 * USEC_PER_MSEC, ndisc_timeout, nd);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_priority(nd->timeout_event_source, nd->event_priority);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(nd->timeout_event_source, "ndisc-timeout-no-ra");
+
r = sd_event_source_set_enabled(nd->timeout_event_source, SD_EVENT_ONESHOT);
if (r < 0) {
log_ndisc_errno(r, "Error reenabling timer: %m");
goto fail;
}
+ log_ndisc("Sent Router Solicitation, next solicitation in %s",
+ format_timespan(time_string, FORMAT_TIMESPAN_MAX,
+ nd->retransmit_time, USEC_PER_SEC));
+
return 0;
fail:
return 0;
}
+static int ndisc_timeout_no_ra(sd_event_source *s, uint64_t usec, void *userdata) {
+ sd_ndisc *nd = userdata;
+
+ assert(s);
+ assert(nd);
+
+ log_ndisc("No RA received before link confirmation timeout");
+
+ nd->timeout_no_ra = sd_event_source_unref(nd->timeout_no_ra);
+ ndisc_callback(nd, SD_NDISC_EVENT_TIMEOUT, NULL);
+
+ return 0;
+}
+
_public_ int sd_ndisc_stop(sd_ndisc *nd) {
assert_return(nd, -EINVAL);
_public_ int sd_ndisc_start(sd_ndisc *nd) {
int r;
+ usec_t time_now;
assert_return(nd, -EINVAL);
assert_return(nd->event, -EINVAL);
assert(!nd->recv_event_source);
assert(!nd->timeout_event_source);
+ r = sd_event_now(nd->event, clock_boottime_or_monotonic(), &time_now);
+ if (r < 0)
+ goto fail;
+
nd->fd = icmp6_bind_router_solicitation(nd->ifindex);
if (nd->fd < 0)
return nd->fd;
(void) sd_event_source_set_description(nd->timeout_event_source, "ndisc-timeout");
+ r = sd_event_add_time(nd->event, &nd->timeout_no_ra,
+ clock_boottime_or_monotonic(),
+ time_now + NDISC_TIMEOUT_NO_RA_USEC,
+ 10 * USEC_PER_MSEC, ndisc_timeout_no_ra, nd);
+ if (r < 0)
+ goto fail;
+
+ r = sd_event_source_set_priority(nd->timeout_no_ra, nd->event_priority);
+ if (r < 0)
+ goto fail;
+
+ (void) sd_event_source_set_description(nd->timeout_no_ra, "ndisc-timeout-no-ra");
+
log_ndisc("Started IPv6 Router Solicitation client");
return 1;