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/*
* answer.c -- manipulating query answers and encoding them.
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/
#include "config.h"
#include <string.h>
#include "answer.h"
#include "packet.h"
#include "query.h"
void
answer_init(answer_type *answer)
{
answer->rrset_count = 0;
}
int
answer_add_rrset(answer_type *answer, rr_section_type section,
domain_type *domain, rrset_type *rrset)
{
size_t i;
assert(section >= ANSWER_SECTION && section < RR_SECTION_COUNT);
assert(domain);
assert(rrset);
/* Don't add an RRset multiple times. */
for (i = 0; i < answer->rrset_count; ++i) {
if (answer->rrsets[i] == rrset &&
answer->domains[i]->number == domain->number) {
if (section < answer->section[i]) {
answer->section[i] = section;
return 1;
} else {
return 0;
}
}
}
if (answer->rrset_count >= MAXRRSPP) {
/* XXX: Generate warning/error? */
return 0;
}
answer->section[answer->rrset_count] = section;
answer->domains[answer->rrset_count] = domain;
answer->rrsets[answer->rrset_count] = rrset;
++answer->rrset_count;
return 1;
}
void
encode_answer(query_type *q, const answer_type *answer)
{
uint16_t counts[RR_SECTION_COUNT];
rr_section_type section;
size_t i;
int minimal_respsize = IPV4_MINIMAL_RESPONSE_SIZE;
int done = 0;
#if defined(INET6) && defined(MINIMAL_RESPONSES)
if (q->client_addr.ss_family == AF_INET6)
minimal_respsize = IPV6_MINIMAL_RESPONSE_SIZE;
#endif
for (section = ANSWER_SECTION; section < RR_SECTION_COUNT; ++section) {
counts[section] = 0;
}
for (section = ANSWER_SECTION;
!TC(q->packet) && section < RR_SECTION_COUNT;
++section) {
for (i = 0; !TC(q->packet) && i < answer->rrset_count; ++i) {
if (answer->section[i] == section) {
counts[section] += packet_encode_rrset(
q,
answer->domains[i],
answer->rrsets[i],
section, minimal_respsize, &done);
}
}
#ifdef MINIMAL_RESPONSES
/**
* done is set prematurely, because the minimal response size
* has been reached. No need to try adding RRsets in following
* sections.
*/
if (done) {
/* delegations should have a usable address in it */
if(section == ADDITIONAL_A_SECTION &&
counts[ADDITIONAL_A_SECTION] == 0 &&
q->delegation_domain)
TC_SET(q->packet);
break;
}
#endif
}
ANCOUNT_SET(q->packet, counts[ANSWER_SECTION]);
NSCOUNT_SET(q->packet,
counts[AUTHORITY_SECTION]
+ counts[OPTIONAL_AUTHORITY_SECTION]);
ARCOUNT_SET(q->packet,
counts[ADDITIONAL_A_SECTION]
+ counts[ADDITIONAL_AAAA_SECTION]
+ counts[ADDITIONAL_OTHER_SECTION]);
}
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