along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
+#include "alloc-util.h"
+#include "dns-domain.h"
#include "resolved-dns-answer.h"
-#include "resolved-dns-domain.h"
+#include "resolved-dns-dnssec.h"
+#include "string-util.h"
DnsAnswer *dns_answer_new(unsigned n) {
DnsAnswer *a;
- assert(n > 0);
-
- a = malloc0(offsetof(DnsAnswer, rrs) + sizeof(DnsResourceRecord*) * n);
+ a = malloc0(offsetof(DnsAnswer, items) + sizeof(DnsAnswerItem) * n);
if (!a)
return NULL;
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;
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--;
return NULL;
}
-int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr) {
+static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) {
+ assert(rr);
+
+ if (!a)
+ return -ENOSPC;
+
+ if (a->n_rrs >= a->n_allocated)
+ return -ENOSPC;
+
+ a->items[a->n_rrs].rr = dns_resource_record_ref(rr);
+ a->items[a->n_rrs].ifindex = ifindex;
+ a->n_rrs++;
+
+ return 1;
+}
+
+static int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) {
+ DnsResourceRecord *rr;
+ int ifindex, r;
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, source) {
+ r = dns_answer_add_raw(a, rr, ifindex);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) {
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 */
- if (rr->ttl == 0 || (rr->ttl > a->rrs[i]->ttl && a->rrs[i]->ttl != 0)) {
+ if (rr->ttl == 0 || (rr->ttl > a->items[i].rr->ttl && a->items[i].rr->ttl != 0)) {
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;
}
return 0;
}
}
- if (a->n_rrs >= a->n_allocated)
- return -ENOSPC;
+ return dns_answer_add_raw(a, rr, ifindex);
+}
- a->rrs[a->n_rrs++] = dns_resource_record_ref(rr);
- return 1;
+static int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) {
+ DnsResourceRecord *rr;
+ int ifindex, r;
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, b) {
+ r = dns_answer_add(a, rr, ifindex);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
}
-int dns_answer_contains(DnsAnswer *a, DnsResourceKey *key) {
- unsigned i;
+int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex) {
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);
+}
+
+int 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);
+}
+
+int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key) {
+ DnsResourceRecord *i;
+ int r;
+
assert(key);
- for (i = 0; i < a->n_rrs; i++) {
- r = dns_resource_key_match_rr(key, a->rrs[i]);
+ if (!a)
+ return 0;
+
+ DNS_ANSWER_FOREACH(i, a) {
+ r = dns_resource_key_match_rr(key, i, NULL);
if (r < 0)
return r;
if (r > 0)
return 0;
}
-int dns_answer_find_soa(DnsAnswer *a, DnsResourceKey *key, DnsResourceRecord **ret) {
- unsigned i;
+int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr) {
+ DnsResourceRecord *i;
+ int r;
+
+ assert(rr);
+
+ DNS_ANSWER_FOREACH(i, a) {
+ r = dns_resource_record_equal(i, rr);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ return 1;
+ }
+
+ return 0;
+}
+
+int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) {
+ DnsResourceRecord *rr;
+ int r;
- assert(a);
assert(key);
- assert(ret);
- for (i = 0; i < a->n_rrs; i++) {
+ if (!a)
+ return 0;
- if (a->rrs[i]->key->class != DNS_CLASS_IN)
- continue;
+ /* For a SOA record we can never find a matching SOA record */
+ if (key->type == DNS_TYPE_SOA)
+ return 0;
- if (a->rrs[i]->key->type != DNS_TYPE_SOA)
- continue;
+ DNS_ANSWER_FOREACH(rr, a) {
+ r = dns_resource_key_match_soa(key, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ if (ret)
+ *ret = rr;
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) {
+ DnsResourceRecord *rr;
+ int r;
- if (dns_name_endswith(DNS_RESOURCE_KEY_NAME(key), DNS_RESOURCE_KEY_NAME(a->rrs[i]->key))) {
- *ret = a->rrs[i];
+ assert(key);
+
+ if (!a)
+ return 0;
+
+ /* 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(rr, 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;
return 1;
}
}
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 */
- if (a) {
- for (i = 0; i < a->n_rrs; i++) {
- r = dns_answer_add(ret, a->rrs[i]);
- if (r < 0)
- return NULL;
- }
+ 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 (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;
+ int ifindex;
+
+ copy = dns_answer_new((*a)->n_rrs);
+ if (!copy)
+ return -ENOMEM;
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, *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);
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_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key) {
+ DnsResourceRecord *rr_source;
+ int ifindex_source, r;
+
+ assert(a);
+ assert(key);
+
+ /* Copy all RRs matching the specified key from source into *a */
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr_source, ifindex_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);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+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
+ * depending on whether the sender is a link-local address. */
+
+ 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;
}
- k = ret;
- ret = NULL;
+ *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
+ * possibly, 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. */
- return k;
+ 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;
}
projects / thirdparty / systemd.git / blobdiff