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-rw-r--r--src/resolve/resolved-dns-answer.c766
1 files changed, 694 insertions, 72 deletions
diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c
index f77b98e505..ab85754bf7 100644
--- a/src/resolve/resolved-dns-answer.c
+++ b/src/resolve/resolved-dns-answer.c
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
/***
This file is part of systemd.
@@ -19,13 +17,16 @@
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
-#include "resolved-dns-answer.h"
+#include "alloc-util.h"
#include "dns-domain.h"
+#include "resolved-dns-answer.h"
+#include "resolved-dns-dnssec.h"
+#include "string-util.h"
DnsAnswer *dns_answer_new(unsigned n) {
DnsAnswer *a;
- a = malloc0(offsetof(DnsAnswer, rrs) + sizeof(DnsResourceRecord*) * n);
+ a = malloc0(offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * n);
if (!a)
return NULL;
@@ -44,6 +45,18 @@ DnsAnswer *dns_answer_ref(DnsAnswer *a) {
return a;
}
+static void dns_answer_flush(DnsAnswer *a) {
+ DnsResourceRecord *rr;
+
+ if (!a)
+ return;
+
+ DNS_ANSWER_FOREACH(rr, a)
+ dns_resource_record_unref(rr);
+
+ a->n_rrs = 0;
+}
+
DnsAnswer *dns_answer_unref(DnsAnswer *a) {
if (!a)
return NULL;
@@ -51,11 +64,7 @@ DnsAnswer *dns_answer_unref(DnsAnswer *a) {
assert(a->n_ref > 0);
if (a->n_ref == 1) {
- unsigned i;
-
- for (i = 0; i < a->n_rrs; i++)
- dns_resource_record_unref(a->rrs[i]);
-
+ dns_answer_flush(a);
free(a);
} else
a->n_ref--;
@@ -63,39 +72,120 @@ DnsAnswer *dns_answer_unref(DnsAnswer *a) {
return NULL;
}
-int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr) {
+static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {
+ assert(rr);
+
+ if (!a)
+ return -ENOSPC;
+
+ if (a->n_rrs >= a->n_allocated)
+ return -ENOSPC;
+
+ a->items[a->n_rrs++] = (DnsAnswerItem) {
+ .rr = dns_resource_record_ref(rr),
+ .ifindex = ifindex,
+ .flags = flags,
+ };
+
+ return 1;
+}
+
+static int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) {
+ DnsResourceRecord *rr;
+ DnsAnswerFlags flags;
+ int ifindex, r;
+
+ DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, source) {
+ r = dns_answer_add_raw(a, rr, ifindex, flags);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {
unsigned i;
int r;
- assert(a);
assert(rr);
+ if (!a)
+ return -ENOSPC;
+ if (a->n_ref > 1)
+ return -EBUSY;
+
for (i = 0; i < a->n_rrs; i++) {
- r = dns_resource_record_equal(a->rrs[i], rr);
+ if (a->items[i].ifindex != ifindex)
+ continue;
+
+ r = dns_resource_record_equal(a->items[i].rr, rr);
if (r < 0)
return r;
if (r > 0) {
- /* Entry already exists, keep the entry with
- * the higher RR, or the one with TTL 0 */
+ /* Don't mix contradicting TTLs (see below) */
+ if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0))
+ return -EINVAL;
- if (rr->ttl == 0 || (rr->ttl > a->rrs[i]->ttl && a->rrs[i]->ttl != 0)) {
+ /* Entry already exists, keep the entry with
+ * the higher RR. */
+ if (rr->ttl > a->items[i].rr->ttl) {
dns_resource_record_ref(rr);
- dns_resource_record_unref(a->rrs[i]);
- a->rrs[i] = rr;
+ dns_resource_record_unref(a->items[i].rr);
+ a->items[i].rr = rr;
}
+ a->items[i].flags |= flags;
return 0;
}
+
+ r = dns_resource_key_equal(a->items[i].rr->key, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ /* There's already an RR of the same RRset in
+ * place! Let's see if the TTLs more or less
+ * match. We don't really care if they match
+ * precisely, but we do care whether one is 0
+ * and the other is not. See RFC 2181, Section
+ * 5.2.*/
+
+ if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0))
+ return -EINVAL;
+ }
}
- if (a->n_rrs >= a->n_allocated)
- return -ENOSPC;
+ return dns_answer_add_raw(a, rr, ifindex, flags);
+}
- a->rrs[a->n_rrs++] = dns_resource_record_ref(rr);
- return 1;
+static int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) {
+ DnsResourceRecord *rr;
+ DnsAnswerFlags flags;
+ int ifindex, r;
+
+ DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, b) {
+ r = dns_answer_add(a, rr, ifindex, flags);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
}
-int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl) {
+int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) {
+ int r;
+
+ assert(a);
+ assert(rr);
+
+ r = dns_answer_reserve_or_clone(a, 1);
+ if (r < 0)
+ return r;
+
+ return dns_answer_add(*a, rr, ifindex, flags);
+}
+
+int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl, int ifindex) {
_cleanup_(dns_resource_record_unrefp) DnsResourceRecord *soa = NULL;
soa = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_SOA, name);
@@ -118,48 +208,204 @@ int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl) {
soa->soa.expire = 1;
soa->soa.minimum = ttl;
- return dns_answer_add(a, soa);
+ return dns_answer_add(a, soa, ifindex, DNS_ANSWER_AUTHENTICATED);
}
-int dns_answer_contains(DnsAnswer *a, DnsResourceKey *key) {
- unsigned i;
+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(a);
assert(key);
- for (i = 0; i < a->n_rrs; i++) {
- r = dns_resource_key_match_rr(key, a->rrs[i]);
+ 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)
+ if (r == 0)
+ continue;
+
+ if (!ret_flags)
return 1;
+
+ if (found)
+ flags &= i_flags;
+ else {
+ flags = i_flags;
+ found = true;
+ }
}
- return 0;
+ if (ret_flags)
+ *ret_flags = flags;
+
+ return found;
}
-int dns_answer_find_soa(DnsAnswer *a, DnsResourceKey *key, DnsResourceRecord **ret) {
- unsigned i;
+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_contains_zone_nsec3(DnsAnswer *answer, const char *zone) {
+ DnsResourceRecord *rr;
+ int r;
+
+ /* Checks whether the specified answer contains at least one NSEC3 RR in the specified zone */
+
+ DNS_ANSWER_FOREACH(rr, answer) {
+ const char *p;
+
+ if (rr->key->type != DNS_TYPE_NSEC3)
+ continue;
+
+ p = dns_resource_key_name(rr->key);
+ r = dns_name_parent(&p);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dns_name_equal(p, zone);
+ if (r != 0)
+ return r;
+ }
+
+ 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(a);
assert(key);
- assert(ret);
/* For a SOA record we can never find a matching SOA record */
if (key->type == DNS_TYPE_SOA)
return 0;
- for (i = 0; i < a->n_rrs; i++) {
+ 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 (a->rrs[i]->key->class != DNS_CLASS_IN)
- continue;
+ 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;
+ }
- if (a->rrs[i]->key->type != DNS_TYPE_SOA)
- continue;
+ soa = rr;
+ soa_flags = rr_flags;
+ }
+ }
+
+ if (!soa)
+ return 0;
+
+ if (ret)
+ *ret = soa;
+ if (flags)
+ *flags = soa_flags;
- if (dns_name_endswith(DNS_RESOURCE_KEY_NAME(key), DNS_RESOURCE_KEY_NAME(a->rrs[i]->key))) {
- *ret = a->rrs[i];
+ 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 (!dns_type_may_redirect(key->type))
+ 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;
}
}
@@ -167,47 +413,279 @@ int dns_answer_find_soa(DnsAnswer *a, DnsResourceKey *key, DnsResourceRecord **r
return 0;
}
-DnsAnswer *dns_answer_merge(DnsAnswer *a, DnsAnswer *b) {
- _cleanup_(dns_answer_unrefp) DnsAnswer *ret = NULL;
- DnsAnswer *k;
+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;
- if (a && (!b || b->n_rrs <= 0))
- return dns_answer_ref(a);
- if ((!a || a->n_rrs <= 0) && b)
- return dns_answer_ref(b);
+ assert(a);
+ assert(key);
- ret = dns_answer_new((a ? a->n_rrs : 0) + (b ? b->n_rrs : 0));
- if (!ret)
- return NULL;
+ /* 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;
- if (a) {
- for (i = 0; i < a->n_rrs; i++) {
- r = dns_answer_add(ret, a->rrs[i]);
+ 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 NULL;
+ 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_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rm) {
+ bool found = false, other = false;
+ DnsResourceRecord *rr;
+ unsigned i;
+ int r;
+
+ assert(a);
+ assert(rm);
+
+ /* Remove all entries matching the specified RR from *a */
+
+ DNS_ANSWER_FOREACH(rr, *a) {
+ r = dns_resource_record_equal(rr, rm);
+ 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 (b) {
- for (i = 0; i < b->n_rrs; i++) {
- r = dns_answer_add(ret, b->rrs[i]);
+ 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_record_equal(rr, rm);
if (r < 0)
- return NULL;
+ 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_record_equal((*a)->items[i].rr, rm);
+ 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;
}
- k = ret;
- ret = NULL;
+ 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 k;
+ return dns_answer_remove_by_key(from, key);
}
void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) {
- DnsResourceRecord **rrs;
+ DnsAnswerItem *items;
unsigned i, start, end;
- assert(a);
+
+ if (!a)
+ return;
if (a->n_rrs <= 1)
return;
@@ -218,19 +696,163 @@ void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) {
/* RFC 4795, Section 2.6 suggests we should order entries
* depending on whether the sender is a link-local address. */
- rrs = newa(DnsResourceRecord*, a->n_rrs);
+ items = newa(DnsAnswerItem, a->n_rrs);
for (i = 0; i < a->n_rrs; i++) {
- if (a->rrs[i]->key->class == DNS_CLASS_IN &&
- ((a->rrs[i]->key->type == DNS_TYPE_A && in_addr_is_link_local(AF_INET, (union in_addr_union*) &a->rrs[i]->a.in_addr) != prefer_link_local) ||
- (a->rrs[i]->key->type == DNS_TYPE_AAAA && in_addr_is_link_local(AF_INET6, (union in_addr_union*) &a->rrs[i]->aaaa.in6_addr) != prefer_link_local)))
- /* Order address records that are are not preferred to the end of the array */
- rrs[end--] = a->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 not preferred to the end of the array */
+ items[end--] = a->items[i];
else
/* Order all other records to the beginning of the array */
- rrs[start++] = a->rrs[i];
+ items[start++] = a->items[i];
}
assert(start == end+1);
- memcpy(a->rrs, rrs, sizeof(DnsResourceRecord*) * a->n_rrs);
+ 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
+ * possible, since we are not the sole owner, then allocate a
+ * new, appropriately sized one. Either way, after this call
+ * the object will only have a single reference, and has room
+ * for at least the specified number of RRs. */
+
+ 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;
+
+ if (!f)
+ f = stdout;
+
+ DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) {
+ const char *t;
+
+ fputc('\t', f);
+
+ t = dns_resource_record_to_string(rr);
+ if (!t) {
+ 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);
+ }
+}
+
+bool dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname) {
+ DnsResourceRecord *rr;
+ int r;
+
+ assert(cname);
+
+ /* Checks whether the answer contains a DNAME record that indicates that the specified CNAME record is
+ * synthesized from it */
+
+ if (cname->key->type != DNS_TYPE_CNAME)
+ return 0;
+
+ DNS_ANSWER_FOREACH(rr, a) {
+ _cleanup_free_ char *n = NULL;
+
+ if (rr->key->type != DNS_TYPE_DNAME)
+ continue;
+ if (rr->key->class != cname->key->class)
+ continue;
+
+ r = dns_name_change_suffix(cname->cname.name, rr->dname.name, dns_resource_key_name(rr->key), &n);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ r = dns_name_equal(n, dns_resource_key_name(cname->key));
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 1;
+
+ }
+
+ return 0;
}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-23 01:01:40 +0000