Use dst_algorithm_fromdata() to extract DST algorithm numbers

dns_resolver_algorithm_supported() open-coded the extraction for
PRIVATEDNS and PRIVATEOID keys, and the PRIVATEDNS copy never set the
active region on the buffer, so dns_name_fromwire() failed and every
PRIVATEDNS key was treated as unsupported.

Replace both copies with dst_algorithm_fromdata(), which sets up the
buffer correctly and passes other algorithms through unchanged.

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 9b0ac0ce48d23b944d69846132aaa4630518ff98..592cbac84b85096330db369ebf28903f87142cde 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -11191,25 +11191,13 @@ dns_resolver_algorithm_supported(dns_resolver_t *resolver,
         * Look up the DST algorithm identifier for private-OID
         * and private-DNS keys.
         */
-       if (alg == DST_ALG_PRIVATEDNS && private != NULL) {
-               isc_buffer_t b;
-               isc_buffer_init(&b, private, len);
-               isc_buffer_add(&b, len);
-               alg = dst_algorithm_fromprivatedns(&b);
+       if (private != NULL) {
+               alg = dst_algorithm_fromdata(alg, private, len);
                if (alg == 0) {
                        return false;
                }
        }
 
-       if (alg == DST_ALG_PRIVATEOID && private != NULL) {
-               isc_buffer_t b;
-               isc_buffer_init(&b, private, len);
-               isc_buffer_add(&b, len);
-               alg = dst_algorithm_fromprivateoid(&b);
-               if (alg == 0) {
-                       return false;
-               }
-       }
        if (dns_nametree_covered(resolver->algorithms, name, NULL, alg)) {
                return false;
        }