+#include <string.h>
+
#include "util.h"
#include "psched.h"
+#define FLX_QUERY_HISTORY_MSEC 700
+#define FLX_QUERY_DEFER_MSEC 100
+#define FLX_RESPONSE_HISTORY_MSEC 700
+#define FLX_RESPONSE_DEFER_MSEC 20
+#define FLX_RESPONSE_JITTER_MSEC 100
+
flxPacketScheduler *flx_packet_scheduler_new(flxServer *server, flxInterface *i) {
flxPacketScheduler *s;
qj->done = 1;
- /* Drop query after 100ms from history */
- flx_elapse_time(&tv, 100, 0);
+ /* Drop query after some time from history from history */
+ flx_elapse_time(&tv, FLX_QUERY_HISTORY_MSEC, 0);
flx_time_event_queue_update(s->server->time_event_queue, qj->time_event, &tv);
+
+ g_get_current_time(&qj->delivery);
}
return d;
return NULL;
}
-void flx_packet_scheduler_post_query(flxPacketScheduler *s, flxKey *key) {
+flxQueryJob* query_job_new(flxPacketScheduler *s, flxKey *key) {
flxQueryJob *qj;
- GTimeVal tv;
g_assert(s);
g_assert(key);
- if (look_for_query(s, key))
- return;
-
qj = g_new(flxQueryJob, 1);
+ qj->scheduler = s;
qj->key = flx_key_ref(key);
qj->done = FALSE;
+ qj->time_event = NULL;
+
+ FLX_LLIST_PREPEND(flxQueryJob, jobs, s->query_jobs, qj);
- flx_elapse_time(&tv, 100, 0);
- qj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &tv, query_elapse, qj);
- qj->scheduler = s;
+ return qj;
+}
- FLX_LLIST_PREPEND(flxQueryJob, jobs, s->query_jobs, qj);
+void flx_packet_scheduler_post_query(flxPacketScheduler *s, flxKey *key, gboolean immediately) {
+ GTimeVal tv;
+ flxQueryJob *qj;
+
+ g_assert(s);
+ g_assert(key);
+
+ flx_elapse_time(&tv, immediately ? 0 : FLX_QUERY_DEFER_MSEC, 0);
+
+ if ((qj = look_for_query(s, key))) {
+ glong d = flx_timeval_diff(&tv, &qj->delivery);
+
+ /* Duplicate questions suppression */
+ if (d >= 0 && d <= FLX_QUERY_HISTORY_MSEC*1000) {
+ g_message("WARNING! DUPLICATE QUERY SUPPRESSION ACTIVE!");
+ return;
+ }
+
+ query_job_free(s, qj);
+ }
+
+ qj = query_job_new(s, key);
+ qj->delivery = tv;
+ qj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &qj->delivery, query_elapse, qj);
}
static guint8* packet_add_response_job(flxPacketScheduler *s, flxDnsPacket *p, flxResponseJob *rj) {
rj->done = 1;
- /* Drop response after 1s from history */
- flx_elapse_time(&tv, 1000, 0);
+ /* Drop response after some time from history */
+ flx_elapse_time(&tv, FLX_RESPONSE_HISTORY_MSEC, 0);
flx_time_event_queue_update(s->server->time_event_queue, rj->time_event, &tv);
+
+ g_get_current_time(&rj->delivery);
}
return d;
}
-
-static void response_elapse(flxTimeEvent *e, gpointer data) {
- flxResponseJob *rj = data;
- flxPacketScheduler *s;
+static void send_response_packet(flxPacketScheduler *s, flxResponseJob *rj) {
flxDnsPacket *p;
guint n;
- guint8 *d;
-
- g_assert(rj);
- s = rj->scheduler;
- if (rj->done) {
- /* Lets remove it from the history */
- response_job_free(s, rj);
- return;
- }
+ g_assert(s);
p = flx_dns_packet_new_response(s->interface->hardware->mtu - 200);
- d = packet_add_response_job(s, p, rj);
- g_assert(d);
- n = 1;
+ n = 0;
+
+ /* If a job was specified, put it in the packet. */
+ if (rj) {
+ guint8 *d;
+ d = packet_add_response_job(s, p, rj);
+ g_assert(d);
+ n++;
+ }
/* Try to fill up packet with more responses, if available */
for (rj = s->response_jobs; rj; rj = rj->jobs_next) {
flx_dns_packet_free(p);
}
+static void response_elapse(flxTimeEvent *e, gpointer data) {
+ flxResponseJob *rj = data;
+ flxPacketScheduler *s;
+
+ g_assert(rj);
+ s = rj->scheduler;
+
+ if (rj->done) {
+ /* Lets remove it from the history */
+ response_job_free(s, rj);
+ return;
+ }
+
+ send_response_packet(s, rj);
+}
+
static flxResponseJob* look_for_response(flxPacketScheduler *s, flxRecord *record) {
flxResponseJob *rj;
g_assert(record);
for (rj = s->response_jobs; rj; rj = rj->jobs_next)
- if (flx_record_equal(rj->record, record))
+ if (flx_record_equal_no_ttl(rj->record, record))
return rj;
return NULL;
}
-void flx_packet_scheduler_post_response(flxPacketScheduler *s, flxRecord *record) {
+static flxResponseJob* response_job_new(flxPacketScheduler *s, flxRecord *record) {
flxResponseJob *rj;
- GTimeVal tv;
g_assert(s);
g_assert(record);
- if (look_for_response(s, record))
- return;
-
rj = g_new(flxResponseJob, 1);
+ rj->scheduler = s;
rj->record = flx_record_ref(record);
rj->done = FALSE;
+ rj->time_event = NULL;
+
+ FLX_LLIST_PREPEND(flxResponseJob, jobs, s->response_jobs, rj);
- flx_elapse_time(&tv, 20, 100);
- rj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &tv, response_elapse, rj);
- rj->scheduler = s;
+ return rj;
+}
- FLX_LLIST_PREPEND(flxResponseJob, jobs, s->response_jobs, rj);
+void flx_packet_scheduler_post_response(flxPacketScheduler *s, flxRecord *record, gboolean immediately) {
+ flxResponseJob *rj;
+ GTimeVal tv;
+ gchar *t;
+
+ g_assert(s);
+ g_assert(record);
+
+ flx_elapse_time(&tv, immediately ? 0 : FLX_RESPONSE_DEFER_MSEC, immediately ? 0 : FLX_RESPONSE_JITTER_MSEC);
+
+ /* Don't send out duplicates */
+
+ if ((rj = look_for_response(s, record))) {
+ glong d;
+
+ d = flx_timeval_diff(&tv, &rj->delivery);
+
+ /* If there's already a matching packet in our history or in
+ * the schedule, we do nothing. */
+ if (!!record->ttl == !!rj->record->ttl &&
+ d >= 0 && d <= FLX_RESPONSE_HISTORY_MSEC*1000) {
+ g_message("WARNING! DUPLICATE RESPONSE SUPPRESSION ACTIVE!");
+ return;
+ }
+
+ /* Either one was a goodbye packet, but the other was not, so
+ * let's drop the older one. */
+ response_job_free(s, rj);
+ }
+
+ g_message("ACCEPTED NEW RESPONSE [%s]", t = flx_record_to_string(record));
+ g_free(t);
+
+ /* Create a new job and schedule it */
+ rj = response_job_new(s, record);
+ rj->delivery = tv;
+ rj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &rj->delivery, response_elapse, rj);
}
-void flx_packet_scheduler_drop_query(flxPacketScheduler *s, flxKey *key) {
+void flx_packet_scheduler_incoming_query(flxPacketScheduler *s, flxKey *key) {
+ GTimeVal tv;
flxQueryJob *qj;
g_assert(s);
g_assert(key);
+ /* This function is called whenever an incoming query was
+ * receieved. We drop all scheduled queries which match here. The
+ * keyword is "DUPLICATE QUESTION SUPPRESION". */
+
for (qj = s->query_jobs; qj; qj = qj->jobs_next)
if (flx_key_equal(qj->key, key)) {
- if (!qj->done) {
- GTimeVal tv;
- qj->done = TRUE;
-
- /* Drop query after 100ms from history */
- flx_elapse_time(&tv, 100, 0);
- flx_time_event_queue_update(s->server->time_event_queue, qj->time_event, &tv);
- }
+ if (qj->done)
+ return;
- break;
+ goto mark_done;
}
+
+
+ /* No matching job was found. Add the query to the history */
+ qj = query_job_new(s, key);
+
+mark_done:
+ qj->done = TRUE;
+
+ /* Drop the query after some time */
+ flx_elapse_time(&tv, FLX_QUERY_HISTORY_MSEC, 0);
+ qj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &tv, query_elapse, qj);
+
+ g_get_current_time(&qj->delivery);
}
-void flx_packet_scheduler_drop_response(flxPacketScheduler *s, flxRecord *record) {
+void response_job_set_elapse_time(flxPacketScheduler *s, flxResponseJob *rj, guint msec, guint jitter) {
+ GTimeVal tv;
+
+ g_assert(s);
+ g_assert(rj);
+
+ flx_elapse_time(&tv, msec, jitter);
+
+ if (rj->time_event)
+ flx_time_event_queue_update(s->server->time_event_queue, rj->time_event, &tv);
+ else
+ rj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &tv, response_elapse, rj);
+
+}
+
+void flx_packet_scheduler_incoming_response(flxPacketScheduler *s, flxRecord *record) {
flxResponseJob *rj;
g_assert(s);
g_assert(record);
- for (rj = s->response_jobs; rj; rj = rj->jobs_next)
- if (flx_record_equal(rj->record, record)) {
-
- if (!rj->done) {
- GTimeVal tv;
- rj->done = TRUE;
-
- /* Drop response after 100ms from history */
- flx_elapse_time(&tv, 100, 0);
- flx_time_event_queue_update(s->server->time_event_queue, rj->time_event, &tv);
+ /* This function is called whenever an incoming response was
+ * receieved. We drop all scheduled responses which match
+ * here. The keyword is "DUPLICATE ANSWER SUPPRESION". */
+
+ for (rj = s->response_jobs; rj; rj = rj->jobs_next)
+ if (flx_record_equal_no_ttl(rj->record, record)) {
+
+ if (rj->done) {
+
+ if (!!record->ttl == !!rj->record->ttl) {
+ /* An entry like this is already in our history,
+ * so let's get out of here! */
+
+ return;
+
+ } else {
+ /* Either one was a goodbye packet but other was
+ * none. We remove the history entry, and add a
+ * new one */
+
+ response_job_free(s, rj);
+ break;
+ }
+
+ } else {
+
+ if (!!record->ttl == !!rj->record->ttl) {
+
+ /* The incoming packet matches our scheduled
+ * record, so let's mark that one as done */
+
+ goto mark_done;
+
+ } else {
+
+ /* Either one was a goodbye packet but other was
+ * none. We ignore the incoming packet. */
+
+ return;
+ }
}
-
- break;
}
+
+ /* No matching job was found. Add the query to the history */
+ rj = response_job_new(s, record);
+
+mark_done:
+ rj->done = TRUE;
+
+ /* Drop response after 500ms from history */
+ response_job_set_elapse_time(s, rj, FLX_RESPONSE_HISTORY_MSEC, 0);
+
+ g_get_current_time(&rj->delivery);
+}
+
+void flx_packet_scheduler_flush_responses(flxPacketScheduler *s) {
+ flxResponseJob *rj;
+
+ g_assert(s);
+
+ /* Send all scheduled responses, ignoring the scheduled time */
+
+ for (rj = s->response_jobs; rj; rj = rj->jobs_next)
+ if (!rj->done)
+ send_response_packet(s, rj);
}
projects / catta / blobdiff