bind9/lib/ns/server.c
Ondřej Surý 58a518adca Change the default ENDS buffer size to 1232 for DNS Flag Day 2020
The DNS Flag Day 2020 aims to remove the IP fragmentation problem from
the UDP DNS communication.  In this commit, we implement the minimal
required changes by changing the defaults for `edns-udp-size`,
`max-udp-size` and `nocookie-udp-size` to `1232` (the value picked by
DNS Flag Day 2020).

(cherry picked from commit bb990030d3)
2020-10-06 09:35:20 +02:00

229 lines
5.4 KiB
C

/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*! \file */
#include <stdbool.h>
#include <isc/mem.h>
#include <isc/stats.h>
#include <isc/util.h>
#include <dns/stats.h>
#include <dns/tkey.h>
#include <ns/query.h>
#include <ns/server.h>
#include <ns/stats.h>
#define SCTX_MAGIC ISC_MAGIC('S', 'c', 't', 'x')
#define SCTX_VALID(s) ISC_MAGIC_VALID(s, SCTX_MAGIC)
#define CHECKFATAL(op) \
do { \
result = (op); \
RUNTIME_CHECK(result == ISC_R_SUCCESS); \
} while (0)
isc_result_t
ns_server_create(isc_mem_t *mctx, ns_matchview_t matchingview,
ns_server_t **sctxp) {
ns_server_t *sctx;
isc_result_t result;
REQUIRE(sctxp != NULL && *sctxp == NULL);
sctx = isc_mem_get(mctx, sizeof(*sctx));
memset(sctx, 0, sizeof(*sctx));
isc_mem_attach(mctx, &sctx->mctx);
isc_refcount_init(&sctx->references, 1);
isc_quota_init(&sctx->xfroutquota, 10);
isc_quota_init(&sctx->tcpquota, 10);
isc_quota_init(&sctx->recursionquota, 100);
CHECKFATAL(dns_tkeyctx_create(mctx, &sctx->tkeyctx));
CHECKFATAL(ns_stats_create(mctx, ns_statscounter_max, &sctx->nsstats));
CHECKFATAL(dns_rdatatypestats_create(mctx, &sctx->rcvquerystats));
CHECKFATAL(dns_opcodestats_create(mctx, &sctx->opcodestats));
CHECKFATAL(dns_rcodestats_create(mctx, &sctx->rcodestats));
CHECKFATAL(isc_stats_create(mctx, &sctx->udpinstats4,
dns_sizecounter_in_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->udpoutstats4,
dns_sizecounter_out_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->udpinstats6,
dns_sizecounter_in_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->udpoutstats6,
dns_sizecounter_out_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->tcpinstats4,
dns_sizecounter_in_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->tcpoutstats4,
dns_sizecounter_out_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->tcpinstats6,
dns_sizecounter_in_max));
CHECKFATAL(isc_stats_create(mctx, &sctx->tcpoutstats6,
dns_sizecounter_out_max));
sctx->udpsize = 1232;
sctx->transfer_tcp_message_size = 20480;
sctx->fuzztype = isc_fuzz_none;
sctx->fuzznotify = NULL;
sctx->gethostname = NULL;
sctx->matchingview = matchingview;
sctx->answercookie = true;
ISC_LIST_INIT(sctx->altsecrets);
sctx->magic = SCTX_MAGIC;
*sctxp = sctx;
return (ISC_R_SUCCESS);
}
void
ns_server_attach(ns_server_t *src, ns_server_t **dest) {
REQUIRE(SCTX_VALID(src));
REQUIRE(dest != NULL && *dest == NULL);
isc_refcount_increment(&src->references);
*dest = src;
}
void
ns_server_detach(ns_server_t **sctxp) {
ns_server_t *sctx;
REQUIRE(sctxp != NULL && SCTX_VALID(*sctxp));
sctx = *sctxp;
*sctxp = NULL;
if (isc_refcount_decrement(&sctx->references) == 1) {
ns_altsecret_t *altsecret;
while ((altsecret = ISC_LIST_HEAD(sctx->altsecrets)) != NULL) {
ISC_LIST_UNLINK(sctx->altsecrets, altsecret, link);
isc_mem_put(sctx->mctx, altsecret, sizeof(*altsecret));
}
isc_quota_destroy(&sctx->recursionquota);
isc_quota_destroy(&sctx->tcpquota);
isc_quota_destroy(&sctx->xfroutquota);
if (sctx->server_id != NULL) {
isc_mem_free(sctx->mctx, sctx->server_id);
}
if (sctx->blackholeacl != NULL) {
dns_acl_detach(&sctx->blackholeacl);
}
if (sctx->keepresporder != NULL) {
dns_acl_detach(&sctx->keepresporder);
}
if (sctx->tkeyctx != NULL) {
dns_tkeyctx_destroy(&sctx->tkeyctx);
}
if (sctx->nsstats != NULL) {
ns_stats_detach(&sctx->nsstats);
}
if (sctx->rcvquerystats != NULL) {
dns_stats_detach(&sctx->rcvquerystats);
}
if (sctx->opcodestats != NULL) {
dns_stats_detach(&sctx->opcodestats);
}
if (sctx->rcodestats != NULL) {
dns_stats_detach(&sctx->rcodestats);
}
if (sctx->udpinstats4 != NULL) {
isc_stats_detach(&sctx->udpinstats4);
}
if (sctx->tcpinstats4 != NULL) {
isc_stats_detach(&sctx->tcpinstats4);
}
if (sctx->udpoutstats4 != NULL) {
isc_stats_detach(&sctx->udpoutstats4);
}
if (sctx->tcpoutstats4 != NULL) {
isc_stats_detach(&sctx->tcpoutstats4);
}
if (sctx->udpinstats6 != NULL) {
isc_stats_detach(&sctx->udpinstats6);
}
if (sctx->tcpinstats6 != NULL) {
isc_stats_detach(&sctx->tcpinstats6);
}
if (sctx->udpoutstats6 != NULL) {
isc_stats_detach(&sctx->udpoutstats6);
}
if (sctx->tcpoutstats6 != NULL) {
isc_stats_detach(&sctx->tcpoutstats6);
}
sctx->magic = 0;
isc_mem_putanddetach(&sctx->mctx, sctx, sizeof(*sctx));
}
}
isc_result_t
ns_server_setserverid(ns_server_t *sctx, const char *serverid) {
REQUIRE(SCTX_VALID(sctx));
if (sctx->server_id != NULL) {
isc_mem_free(sctx->mctx, sctx->server_id);
sctx->server_id = NULL;
}
if (serverid != NULL) {
sctx->server_id = isc_mem_strdup(sctx->mctx, serverid);
}
return (ISC_R_SUCCESS);
}
void
ns_server_setoption(ns_server_t *sctx, unsigned int option, bool value) {
REQUIRE(SCTX_VALID(sctx));
if (value) {
sctx->options |= option;
} else {
sctx->options &= ~option;
}
}
bool
ns_server_getoption(ns_server_t *sctx, unsigned int option) {
REQUIRE(SCTX_VALID(sctx));
return ((sctx->options & option) != 0);
}