30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering#include "alloc-util.h"

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering#include "dns-domain.h"

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering#include "resolved-dns-answer.h"

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering#include "resolved-dns-dnssec.h"

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering#include "string-util.h"

9bf3b53533cdc9b95c921b71da755401f223f765Lennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart PoetteringDnsAnswer *dns_answer_new(unsigned n) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsAnswer *a;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a = malloc0(offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * n);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return NULL;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->n_ref = 1;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->n_allocated = n;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return a;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart PoetteringDnsAnswer *dns_answer_ref(DnsAnswer *a) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return NULL;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(a->n_ref > 0);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->n_ref++;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return a;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringstatic void dns_answer_flush(DnsAnswer *a) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsResourceRecord *rr;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DNS_ANSWER_FOREACH(rr, a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering dns_resource_record_unref(rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->n_rrs = 0;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart PoetteringDnsAnswer *dns_answer_unref(DnsAnswer *a) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return NULL;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(a->n_ref > 0);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (a->n_ref == 1) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering dns_answer_flush(a);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering free(a);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering } else

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->n_ref--;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return NULL;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringstatic int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return -ENOSPC;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (a->n_rrs >= a->n_allocated)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return -ENOSPC;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->items[a->n_rrs++] = (DnsAnswerItem) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering .rr = dns_resource_record_ref(rr),

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering .ifindex = ifindex,

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering .flags = flags,

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering };

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

b826ab586c9e0a9c0d438a75c28cf3a8ab485929Tom Gundersen return 1;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

b826ab586c9e0a9c0d438a75c28cf3a8ab485929Tom Gundersenstatic int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsResourceRecord *rr;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsAnswerFlags flags;

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt int ifindex, r;

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, source) {

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt r = dns_answer_add_raw(a, rr, ifindex, flags);

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt if (r < 0)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering }

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return 0;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringint dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering unsigned i;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering int r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(rr);

d5099efc47d4e6ac60816b5381a5f607ab03f06eMichal Schmidt

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (!a)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return -ENOSPC;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (a->n_ref > 1)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return -EBUSY;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering for (i = 0; i < a->n_rrs; i++) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (a->items[i].ifindex != ifindex)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering continue;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering r = dns_resource_record_equal(a->items[i].rr, rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (r < 0)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (r > 0) {

ef42202ac8ed27e7ff1fc90ef8bc2590046dff25Zbigniew Jędrzejewski-Szmek /* Entry already exists, keep the entry with

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (rr->ttl == 0 || (rr->ttl > a->items[i].rr->ttl && a->items[i].rr->ttl != 0)) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering dns_resource_record_ref(rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering dns_resource_record_unref(a->items[i].rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->items[i].rr = rr;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering }

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering a->items[i].flags |= flags;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return 0;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering }

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering }

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return dns_answer_add_raw(a, rr, ifindex, flags);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringstatic int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsResourceRecord *rr;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DnsAnswerFlags flags;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering int ifindex, r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, b) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering r = dns_answer_add(a, rr, ifindex, flags);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (r < 0)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering }

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return 0;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringint dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering int r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(a);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering assert(rr);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering r = dns_answer_reserve_or_clone(a, 1);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering if (r < 0)

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return r;

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering return dns_answer_add(*a, rr, ifindex, flags);

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering}

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poettering

30bdd695250eeecbf0b36c1e3c90d67ca03953edLennart Poetteringint dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl) {

_cleanup_(dns_resource_record_unrefp) DnsResourceRecord *soa = NULL;

soa = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_SOA, name);

if (!soa)

return -ENOMEM;

soa->ttl = ttl;

soa->soa.mname = strdup(name);

if (!soa->soa.mname)

return -ENOMEM;

soa->soa.rname = strappend("root.", name);

if (!soa->soa.rname)

return -ENOMEM;

soa->soa.serial = 1;

soa->soa.refresh = 1;

soa->soa.retry = 1;

soa->soa.expire = 1;

soa->soa.minimum = ttl;

return dns_answer_add(a, soa, 0, DNS_ANSWER_AUTHENTICATED);

}

int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) {

DnsAnswerFlags flags = 0, i_flags;

DnsResourceRecord *i;

bool found = false;

int r;

assert(key);

DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) {

r = dns_resource_key_match_rr(key, i, NULL);

if (r < 0)

return r;

if (r == 0)

continue;

if (!ret_flags)

return 1;

if (found)

flags &= i_flags;

else {

flags = i_flags;

found = true;

}

}

if (ret_flags)

*ret_flags = flags;

return found;

}

int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr, DnsAnswerFlags *ret_flags) {

DnsAnswerFlags flags = 0, i_flags;

DnsResourceRecord *i;

bool found = false;

int r;

assert(rr);

DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) {

r = dns_resource_record_equal(i, rr);

if (r < 0)

return r;

if (r == 0)

continue;

if (!ret_flags)

return 1;

if (found)

flags &= i_flags;

else {

flags = i_flags;

found = true;

}

}

if (ret_flags)

*ret_flags = flags;

return found;

}

int dns_answer_contains_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) {

DnsAnswerFlags flags = 0, i_flags;

DnsResourceRecord *i;

bool found = false;

int r;

assert(key);

DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) {

r = dns_resource_key_equal(i->key, key);

if (r < 0)

return r;

if (r == 0)

continue;

if (!ret_flags)

return true;

if (found)

flags &= i_flags;

else {

flags = i_flags;

found = true;

}

}

if (ret_flags)

*ret_flags = flags;

return found;

}

int dns_answer_contains_nsec_or_nsec3(DnsAnswer *a) {

DnsResourceRecord *i;

DNS_ANSWER_FOREACH(i, a) {

if (IN_SET(i->key->type, DNS_TYPE_NSEC, DNS_TYPE_NSEC3))

return true;

}

return false;

}

int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) {

DnsResourceRecord *rr, *soa = NULL;

DnsAnswerFlags rr_flags, soa_flags = 0;

int r;

assert(key);

/* For a SOA record we can never find a matching SOA record */

if (key->type == DNS_TYPE_SOA)

return 0;

DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) {

r = dns_resource_key_match_soa(key, rr->key);

if (r < 0)

return r;

if (r > 0) {

if (soa) {

r = dns_name_endswith(DNS_RESOURCE_KEY_NAME(rr->key), DNS_RESOURCE_KEY_NAME(soa->key));

if (r < 0)

return r;

if (r > 0)

continue;

}

soa = rr;

soa_flags = rr_flags;

}

}

if (!soa)

return 0;

if (ret)

*ret = soa;

if (flags)

*flags = soa_flags;

return 1;

}

int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) {

DnsResourceRecord *rr;

DnsAnswerFlags rr_flags;

int r;

assert(key);

/* For a {C,D}NAME record we can never find a matching {C,D}NAME record */

if (key->type == DNS_TYPE_CNAME || key->type == DNS_TYPE_DNAME)

return 0;

DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) {

r = dns_resource_key_match_cname_or_dname(key, rr->key, NULL);

if (r < 0)

return r;

if (r > 0) {

if (ret)

*ret = rr;

if (flags)

*flags = rr_flags;

return 1;

}

}

return 0;

}

int dns_answer_merge(DnsAnswer *a, DnsAnswer *b, DnsAnswer **ret) {

_cleanup_(dns_answer_unrefp) DnsAnswer *k = NULL;

int r;

assert(ret);

if (dns_answer_size(a) <= 0) {

*ret = dns_answer_ref(b);

return 0;

}

if (dns_answer_size(b) <= 0) {

*ret = dns_answer_ref(a);

return 0;

}

k = dns_answer_new(a->n_rrs + b->n_rrs);

if (!k)

return -ENOMEM;

r = dns_answer_add_raw_all(k, a);

if (r < 0)

return r;

r = dns_answer_add_all(k, b);

if (r < 0)

return r;

*ret = k;

k = NULL;

return 0;

}

int dns_answer_extend(DnsAnswer **a, DnsAnswer *b) {

DnsAnswer *merged;

int r;

assert(a);

r = dns_answer_merge(*a, b, &merged);

if (r < 0)

return r;

dns_answer_unref(*a);

*a = merged;

return 0;

}

int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key) {

bool found = false, other = false;

DnsResourceRecord *rr;

unsigned i;

int r;

assert(a);

assert(key);

/* Remove all entries matching the specified key from *a */

DNS_ANSWER_FOREACH(rr, *a) {

r = dns_resource_key_equal(rr->key, key);

if (r < 0)

return r;

if (r > 0)

found = true;

else

other = true;

if (found && other)

break;

}

if (!found)

return 0;

if (!other) {

*a = dns_answer_unref(*a); /* Return NULL for the empty answer */

return 1;

}

if ((*a)->n_ref > 1) {

_cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL;

DnsAnswerFlags flags;

int ifindex;

copy = dns_answer_new((*a)->n_rrs);

if (!copy)

return -ENOMEM;

DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) {

r = dns_resource_key_equal(rr->key, key);

if (r < 0)

return r;

if (r > 0)

continue;

r = dns_answer_add_raw(copy, rr, ifindex, flags);

if (r < 0)

return r;

}

dns_answer_unref(*a);

*a = copy;

copy = NULL;

return 1;

}

/* Only a single reference, edit in-place */

i = 0;

for (;;) {

if (i >= (*a)->n_rrs)

break;

r = dns_resource_key_equal((*a)->items[i].rr->key, key);

if (r < 0)

return r;

if (r > 0) {

/* Kill this entry */

dns_resource_record_unref((*a)->items[i].rr);

memmove((*a)->items + i, (*a)->items + i + 1, sizeof(DnsAnswerItem) * ((*a)->n_rrs - i - 1));

(*a)->n_rrs --;

continue;

} else

/* Keep this entry */

i++;

}

return 1;

}

int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags) {

DnsResourceRecord *rr_source;

int ifindex_source, r;

DnsAnswerFlags flags_source;

assert(a);

assert(key);

/* Copy all RRs matching the specified key from source into *a */

DNS_ANSWER_FOREACH_FULL(rr_source, ifindex_source, flags_source, source) {

r = dns_resource_key_equal(rr_source->key, key);

if (r < 0)

return r;

if (r == 0)

continue;

/* Make space for at least one entry */

r = dns_answer_reserve_or_clone(a, 1);

if (r < 0)

return r;

r = dns_answer_add(*a, rr_source, ifindex_source, flags_source|or_flags);

if (r < 0)

return r;

}

return 0;

}

int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags) {

int r;

assert(to);

assert(from);

assert(key);

r = dns_answer_copy_by_key(to, *from, key, or_flags);

if (r < 0)

return r;

return dns_answer_remove_by_key(from, key);

}

void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) {

DnsAnswerItem *items;

unsigned i, start, end;

if (!a)

return;

if (a->n_rrs <= 1)

return;

start = 0;

end = a->n_rrs-1;

/* RFC 4795, Section 2.6 suggests we should order entries

items = newa(DnsAnswerItem, a->n_rrs);

for (i = 0; i < a->n_rrs; i++) {

if (a->items[i].rr->key->class == DNS_CLASS_IN &&

((a->items[i].rr->key->type == DNS_TYPE_A && in_addr_is_link_local(AF_INET, (union in_addr_union*) &a->items[i].rr->a.in_addr) != prefer_link_local) ||

(a->items[i].rr->key->type == DNS_TYPE_AAAA && in_addr_is_link_local(AF_INET6, (union in_addr_union*) &a->items[i].rr->aaaa.in6_addr) != prefer_link_local)))

/* Order address records that are are not preferred to the end of the array */

items[end--] = a->items[i];

else

/* Order all other records to the beginning of the array */

items[start++] = a->items[i];

}

assert(start == end+1);

memcpy(a->items, items, sizeof(DnsAnswerItem) * a->n_rrs);

}

int dns_answer_reserve(DnsAnswer **a, unsigned n_free) {

DnsAnswer *n;

assert(a);

if (n_free <= 0)

return 0;

if (*a) {

unsigned ns;

if ((*a)->n_ref > 1)

return -EBUSY;

ns = (*a)->n_rrs + n_free;

if ((*a)->n_allocated >= ns)

return 0;

/* Allocate more than we need */

ns *= 2;

n = realloc(*a, offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * ns);

if (!n)

return -ENOMEM;

n->n_allocated = ns;

} else {

n = dns_answer_new(n_free);

if (!n)

return -ENOMEM;

}

*a = n;

return 0;

}

int dns_answer_reserve_or_clone(DnsAnswer **a, unsigned n_free) {

_cleanup_(dns_answer_unrefp) DnsAnswer *n = NULL;

int r;

assert(a);

/* Tries to extend the DnsAnswer object. And if that's not

r = dns_answer_reserve(a, n_free);

if (r != -EBUSY)

return r;

assert(*a);

n = dns_answer_new(((*a)->n_rrs + n_free) * 2);

if (!n)

return -ENOMEM;

r = dns_answer_add_raw_all(n, *a);

if (r < 0)

return r;

dns_answer_unref(*a);

*a = n;

n = NULL;

return 0;

}

void dns_answer_dump(DnsAnswer *answer, FILE *f) {

DnsResourceRecord *rr;

DnsAnswerFlags flags;

int ifindex, r;

if (!f)

f = stdout;

DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) {

_cleanup_free_ char *t = NULL;

fputc('\t', f);

r = dns_resource_record_to_string(rr, &t);

if (r < 0) {

log_oom();

continue;

}

fputs(t, f);

if (ifindex != 0 || flags & (DNS_ANSWER_AUTHENTICATED|DNS_ANSWER_CACHEABLE|DNS_ANSWER_SHARED_OWNER))

fputs("\t;", f);

if (ifindex != 0)

printf(" ifindex=%i", ifindex);

if (flags & DNS_ANSWER_AUTHENTICATED)

fputs(" authenticated", f);

if (flags & DNS_ANSWER_CACHEABLE)

fputs(" cachable", f);

if (flags & DNS_ANSWER_SHARED_OWNER)

fputs(" shared-owner", f);

fputc('\n', f);

}

}