+#include <string.h>
+
#include "util.h"
#include "psched.h"
-flxPacketScheduler *flx_packet_scheduler_new(flxServer *server, flxInterface *i, guchar protocol) {
+#define FLX_QUERY_HISTORY_MSEC 100
+#define FLX_QUERY_DEFER_MSEC 100
+#define FLX_RESPONSE_HISTORY_MSEC 700
+#define FLX_RESPONSE_DEFER_MSEC 20
+#define FLX_RESPONSE_JITTER_MSEC 100
+#define FLX_PROBE_DEFER_MSEC 100
+
+flxPacketScheduler *flx_packet_scheduler_new(flxServer *server, flxInterface *i) {
flxPacketScheduler *s;
g_assert(server);
s = g_new(flxPacketScheduler, 1);
s->server = server;
s->interface = i;
- s->protocol = protocol;
FLX_LLIST_HEAD_INIT(flxQueryJob, s->query_jobs);
FLX_LLIST_HEAD_INIT(flxResponseJob, s->response_jobs);
+ FLX_LLIST_HEAD_INIT(flxKnownAnswer, s->known_answers);
+ FLX_LLIST_HEAD_INIT(flxProbeJob, s->probe_jobs);
return s;
}
g_free(rj);
}
+static void probe_job_free(flxPacketScheduler *s, flxProbeJob *pj) {
+ g_assert(pj);
+
+ if (pj->time_event)
+ flx_time_event_queue_remove(pj->scheduler->server->time_event_queue, pj->time_event);
+
+ FLX_LLIST_REMOVE(flxProbeJob, jobs, s->probe_jobs, pj);
+
+ flx_record_unref(pj->record);
+ g_free(pj);
+}
+
void flx_packet_scheduler_free(flxPacketScheduler *s) {
flxQueryJob *qj;
flxResponseJob *rj;
+ flxProbeJob *pj;
flxTimeEvent *e;
-
+
g_assert(s);
+ g_assert(!s->known_answers);
+
while ((qj = s->query_jobs))
query_job_free(s, qj);
while ((rj = s->response_jobs))
response_job_free(s, rj);
+ while ((pj = s->probe_jobs))
+ probe_job_free(s, pj);
g_free(s);
}
+static gpointer known_answer_walk_callback(flxCache *c, flxKey *pattern, flxCacheEntry *e, gpointer userdata) {
+ flxPacketScheduler *s = userdata;
+ flxKnownAnswer *ka;
+
+ g_assert(c);
+ g_assert(pattern);
+ g_assert(e);
+ g_assert(s);
+
+ if (flx_cache_entry_half_ttl(c, e))
+ return NULL;
+
+ ka = g_new0(flxKnownAnswer, 1);
+ ka->scheduler = s;
+ ka->record = flx_record_ref(e->record);
+
+ FLX_LLIST_PREPEND(flxKnownAnswer, known_answer, s->known_answers, ka);
+ return NULL;
+}
+
static guint8* packet_add_query_job(flxPacketScheduler *s, flxDnsPacket *p, flxQueryJob *qj) {
guint8 *d;
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);
+
+ /* Add all matching known answers to the list */
+ flx_cache_walk(s->interface->cache, qj->key, known_answer_walk_callback, s);
}
return d;
}
-
+
+static void append_known_answers_and_send(flxPacketScheduler *s, flxDnsPacket *p) {
+ flxKnownAnswer *ka;
+ guint n;
+ g_assert(s);
+ g_assert(p);
+
+ n = 0;
+
+ while ((ka = s->known_answers)) {
+
+ while (!flx_dns_packet_append_record(p, ka->record, FALSE)) {
+
+ g_assert(!flx_dns_packet_is_empty(p));
+
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_FLAGS, flx_dns_packet_get_field(p, FLX_DNS_FIELD_FLAGS) | FLX_DNS_FLAG_TC);
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_ANCOUNT, n);
+ flx_interface_send_packet(s->interface, p);
+ flx_dns_packet_free(p);
+
+ p = flx_dns_packet_new_query(s->interface->hardware->mtu - 48);
+ n = 0;
+ }
+
+ FLX_LLIST_REMOVE(flxKnownAnswer, known_answer, s->known_answers, ka);
+ flx_record_unref(ka->record);
+ g_free(ka);
+
+ n++;
+ }
+
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_ANCOUNT, n);
+ flx_interface_send_packet(s->interface, p);
+ flx_dns_packet_free(p);
+}
+
static void query_elapse(flxTimeEvent *e, gpointer data) {
flxQueryJob *qj = data;
flxPacketScheduler *s;
return;
}
- p = flx_dns_packet_new_query(s->interface->mtu - 48);
+ g_assert(!s->known_answers);
+
+ p = flx_dns_packet_new_query(s->interface->hardware->mtu - 48);
d = packet_add_query_job(s, p, qj);
g_assert(d);
n = 1;
n++;
}
- flx_dns_packet_set_field(p, DNS_FIELD_QDCOUNT, n);
- flx_interface_send_packet(s->interface, s->protocol, p);
- flx_dns_packet_free(p);
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_QDCOUNT, n);
+
+ /* Now add known answers */
+ append_known_answers_and_send(s, p);
}
-static flxQueryJob* look_for_query(flxPacketScheduler *s, flxKey *key) {
+flxQueryJob* query_job_new(flxPacketScheduler *s, flxKey *key) {
flxQueryJob *qj;
g_assert(s);
g_assert(key);
- for (qj = s->query_jobs; qj; qj = qj->jobs_next)
- if (flx_key_equal(qj->key, key))
- return qj;
+ 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);
- return NULL;
+ return qj;
}
-void flx_packet_scheduler_post_query(flxPacketScheduler *s, flxKey *key) {
- flxQueryJob *qj;
+void flx_packet_scheduler_post_query(flxPacketScheduler *s, flxKey *key, gboolean immediately) {
GTimeVal tv;
+ flxQueryJob *qj;
g_assert(s);
g_assert(key);
- if (look_for_query(s, key))
- return;
+ flx_elapse_time(&tv, immediately ? 0 : FLX_QUERY_DEFER_MSEC, 0);
- qj = g_new(flxQueryJob, 1);
- qj->key = flx_key_ref(key);
- qj->done = FALSE;
+ for (qj = s->query_jobs; qj; qj = qj->jobs_next)
- 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;
+ if (flx_key_equal(qj->key, key)) {
- FLX_LLIST_PREPEND(flxQueryJob, jobs, s->query_jobs, qj);
+ 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);
+ break;
+ }
+
+ 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) {
g_assert(p);
g_assert(rj);
- if ((d = flx_dns_packet_append_record(p, rj->record, FALSE))) {
+ if ((d = flx_dns_packet_append_record(p, rj->record, rj->flush_cache))) {
GTimeVal tv;
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;
+ g_assert(s);
- if (rj->done) {
- /* Lets remove it from the history */
- response_job_free(s, rj);
- return;
- }
+ p = flx_dns_packet_new_response(s->interface->hardware->mtu - 200);
+ n = 0;
- p = flx_dns_packet_new_response(s->interface->mtu - 200);
- d = packet_add_response_job(s, p, rj);
- g_assert(d);
- n = 1;
+ /* 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) {
n++;
}
- flx_dns_packet_set_field(p, DNS_FIELD_ANCOUNT, n);
- flx_interface_send_packet(s->interface, s->protocol, p);
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_ANCOUNT, n);
+ flx_interface_send_packet(s->interface, p);
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;
+ rj->address_valid = FALSE;
+ rj->flush_cache = FALSE;
+
+ 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, const flxAddress *a, flxRecord *record, gboolean flush_cache, gboolean immediately) {
+ flxResponseJob *rj;
+ GTimeVal tv;
+ gchar *t;
+
+ g_assert(s);
+ g_assert(record);
+
+ g_assert(!flx_key_is_pattern(record->key));
+
+ 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!");
+
+ /* This job is no longer specific to a single querier, so
+ * make sure it isn't suppressed by known answer
+ * suppresion */
+
+ if (rj->address_valid && (!a || flx_address_cmp(a, &rj->address) != 0))
+ rj->address_valid = FALSE;
+
+ rj->flush_cache = flush_cache;
+
+ 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->flush_cache = flush_cache;
+ rj->delivery = tv;
+ rj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &rj->delivery, response_elapse, rj);
+
+ /* Store the address of the host this messages is intended to, so
+ that we can drop this job in case a truncated message with
+ known answer suppresion entries is recieved */
+
+ if ((rj->address_valid = !!a))
+ rj->address = *a;
}
-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;
+
+ 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 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);
+
+ /* 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;
+ }
}
+ }
+
+ /* 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_incoming_known_answer(flxPacketScheduler *s, flxRecord *record, const flxAddress *a) {
+ flxResponseJob *rj;
+
+ g_assert(s);
+ g_assert(record);
+ g_assert(a);
+
+ for (rj = s->response_jobs; rj; rj = rj->jobs_next) {
+
+ g_assert(record->ttl > 0);
+ g_assert(rj->record->ttl/2);
+
+ if (flx_record_equal_no_ttl(rj->record, record))
+ if (rj->address_valid)
+ if (flx_address_cmp(&rj->address, a))
+ if (record->ttl >= rj->record->ttl/2) {
+
+ /* Let's suppress it */
+
+ response_job_free(s, rj);
break;
}
+ }
}
-void flx_packet_scheduler_drop_response(flxPacketScheduler *s, flxRecord *record) {
+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);
+}
+
+static flxProbeJob* probe_job_new(flxPacketScheduler *s, flxRecord *record) {
+ flxProbeJob *pj;
+
g_assert(s);
g_assert(record);
- for (rj = s->response_jobs; rj; rj = rj->jobs_next)
- if (flx_record_equal(rj->record, record)) {
+ pj = g_new(flxProbeJob, 1);
+ pj->scheduler = s;
+ pj->record = flx_record_ref(record);
+ pj->time_event = NULL;
+ pj->chosen = FALSE;
+
+ FLX_LLIST_PREPEND(flxProbeJob, jobs, s->probe_jobs, pj);
- 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);
- }
+ return pj;
+}
+
+static guint8* packet_add_probe_query(flxPacketScheduler *s, flxDnsPacket *p, flxProbeJob *pj) {
+ guint size;
+ guint8 *ret;
+ flxKey *k;
+ g_assert(s);
+ g_assert(p);
+ g_assert(pj);
+
+ g_assert(!pj->chosen);
+
+ /* Estimate the size for this record */
+ size =
+ flx_key_get_estimate_size(pj->record->key) +
+ flx_record_get_estimate_size(pj->record);
+
+ /* Too large */
+ if (size > flx_dns_packet_space(p))
+ return NULL;
+
+ /* Create the probe query */
+ k = flx_key_new(pj->record->key->name, pj->record->key->class, FLX_DNS_TYPE_ANY);
+ ret = flx_dns_packet_append_key(p, k);
+ g_assert(ret);
+
+ /* Mark this job for addition to the packet */
+ pj->chosen = TRUE;
+
+ /* Scan for more jobs whith matching key pattern */
+ for (pj = s->probe_jobs; pj; pj = pj->jobs_next) {
+ if (pj->chosen)
+ continue;
+
+ /* Does the record match the probe? */
+ if (k->class != pj->record->key->class || flx_domain_equal(k->name, pj->record->key->name))
+ continue;
+
+ /* This job wouldn't fit in */
+ if (flx_record_get_estimate_size(pj->record) > flx_dns_packet_space(p))
+ break;
+
+ /* Mark this job for addition to the packet */
+ pj->chosen = TRUE;
+ }
+
+ flx_key_unref(k);
+
+ return ret;
+}
+
+static void probe_elapse(flxTimeEvent *e, gpointer data) {
+ flxProbeJob *pj = data, *next;
+ flxPacketScheduler *s;
+ flxDnsPacket *p;
+ guint n;
+ guint8 *d;
+
+ g_assert(pj);
+ s = pj->scheduler;
+
+ p = flx_dns_packet_new_query(s->interface->hardware->mtu - 48);
+
+ /* Add the import probe */
+ if (!packet_add_probe_query(s, p, pj)) {
+ g_warning("Record too large! ---");
+ flx_dns_packet_free(p);
+ return;
+ }
+
+ n = 1;
+
+ /* Try to fill up packet with more probes, if available */
+ for (pj = s->probe_jobs; pj; pj = pj->jobs_next) {
+
+ if (pj->chosen)
+ continue;
+
+ if (!packet_add_probe_query(s, p, pj))
+ break;
+
+ n++;
+ }
+
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_QDCOUNT, n);
+
+ n = 0;
+
+ /* Now add the chosen records to the authorative section */
+ for (pj = s->probe_jobs; pj; pj = next) {
+
+ next = pj->jobs_next;
+
+ if (!pj->chosen)
+ continue;
+
+ if (!flx_dns_packet_append_record(p, pj->record, TRUE)) {
+ g_warning("Bad probe size estimate!");
+
+ /* Unmark all following jobs */
+ for (; pj; pj = pj->jobs_next)
+ pj->chosen = FALSE;
+
break;
}
+
+ probe_job_free(s, pj);
+ n ++;
+ }
+
+ flx_dns_packet_set_field(p, FLX_DNS_FIELD_NSCOUNT, n);
+
+ /* Send it now */
+ flx_interface_send_packet(s->interface, p);
+ flx_dns_packet_free(p);
+}
+
+void flx_packet_scheduler_post_probe(flxPacketScheduler *s, flxRecord *record, gboolean immediately) {
+ flxProbeJob *pj;
+ GTimeVal tv;
+
+ g_assert(s);
+ g_assert(record);
+ g_assert(!flx_key_is_pattern(record->key));
+
+ flx_elapse_time(&tv, immediately ? 0 : FLX_PROBE_DEFER_MSEC, 0);
+
+ /* No duplication check here... */
+ /* Create a new job and schedule it */
+ pj = probe_job_new(s, record);
+ pj->delivery = tv;
+ pj->time_event = flx_time_event_queue_add(s->server->time_event_queue, &pj->delivery, probe_elapse, pj);
}
projects / catta / blobdiff