diff --git a/lib/dns/include/dns/rdataslab.h b/lib/dns/include/dns/rdataslab.h
index acca54bf78..f74bee626c 100644
--- a/lib/dns/include/dns/rdataslab.h
+++ b/lib/dns/include/dns/rdataslab.h
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: rdataslab.h,v 1.22 2002/02/20 03:34:38 marka Exp $ */
+/* $Id: rdataslab.h,v 1.23 2002/02/20 22:57:13 bwelling Exp $ */
 
 #ifndef DNS_RDATASLAB_H
 #define DNS_RDATASLAB_H 1
@@ -83,6 +83,22 @@ dns_rdataslab_fromrdataset(dns_rdataset_t *rdataset, isc_mem_t *mctx,
  *	<XXX others>
  */
 
+void
+dns_rdataslab_tordataset(unsigned char *slab, unsigned int reservelen,
+			 dns_rdataclass_t rdclass, dns_rdatatype_t rdtype,
+			 dns_rdatatype_t covers, dns_ttl_t ttl,
+			 dns_rdataset_t *rdataset);
+/*
+ * Construct an rdataset from a slab.
+ *
+ * Requires:
+ *	'slab' points to a slab.
+ *	'rdataset' is disassociated.
+ *
+ * Ensures:
+ *	'rdataset' is associated and points to a valid rdataest.
+ */
+
 unsigned int
 dns_rdataslab_size(unsigned char *slab, unsigned int reservelen);
 /*
diff --git a/lib/dns/rdataslab.c b/lib/dns/rdataslab.c
index 13f0a86f3e..7ffb722046 100644
--- a/lib/dns/rdataslab.c
+++ b/lib/dns/rdataslab.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: rdataslab.c,v 1.29 2001/01/09 21:51:25 bwelling Exp $ */
+/* $Id: rdataslab.c,v 1.30 2002/02/20 22:57:12 bwelling Exp $ */
 
 #include <config.h>
 
@@ -152,6 +152,119 @@ dns_rdataslab_fromrdataset(dns_rdataset_t *rdataset, isc_mem_t *mctx,
 	return (result);
 }
 
+static void
+rdataset_disassociate(dns_rdataset_t *rdataset) {
+	UNUSED(rdataset);
+}
+
+static isc_result_t
+rdataset_first(dns_rdataset_t *rdataset) {
+	unsigned char *raw = rdataset->private3;
+	unsigned int count;
+
+	count = raw[0] * 256 + raw[1];
+	if (count == 0) {
+		rdataset->private5 = NULL;
+		return (ISC_R_NOMORE);
+	}
+	raw += 2;
+	/*
+	 * The private4 field is the number of rdata beyond the cursor
+	 * position, so we decrement the total count by one before storing
+	 * it.
+	 */
+	count--;
+	rdataset->private4 = (void *)count;
+	rdataset->private5 = raw;
+
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+rdataset_next(dns_rdataset_t *rdataset) {
+	unsigned int count;
+	unsigned int length;
+	unsigned char *raw;
+
+	count = (unsigned int)rdataset->private4;
+	if (count == 0)
+		return (ISC_R_NOMORE);
+	count--;
+	rdataset->private4 = (void *)count;
+	raw = rdataset->private5;
+	length = raw[0] * 256 + raw[1];
+	raw += length + 2;
+	rdataset->private5 = raw;
+
+	return (ISC_R_SUCCESS);
+}
+
+static void
+rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {
+	unsigned char *raw = rdataset->private5;
+	isc_region_t r;
+
+	REQUIRE(raw != NULL);
+
+	r.length = raw[0] * 256 + raw[1];
+	raw += 2;
+	r.base = raw;
+	dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r);
+}
+
+static void
+rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) {
+	*target = *source;
+
+	/*
+	 * Reset iterator state.
+	 */
+	target->private4 = NULL;
+	target->private5 = NULL;
+}
+
+static unsigned int
+rdataset_count(dns_rdataset_t *rdataset) {
+	unsigned char *raw = rdataset->private3;
+	unsigned int count;
+
+	count = raw[0] * 256 + raw[1];
+
+	return (count);
+}
+
+static dns_rdatasetmethods_t rdataset_methods = {
+	rdataset_disassociate,
+	rdataset_first,
+	rdataset_next,
+	rdataset_current,
+	rdataset_clone,
+	rdataset_count
+};
+
+void
+dns_rdataslab_tordataset(unsigned char *slab, unsigned int reservelen,
+			 dns_rdataclass_t rdclass, dns_rdatatype_t rdtype,
+			 dns_rdatatype_t covers, dns_ttl_t ttl,
+			 dns_rdataset_t *rdataset)
+{
+	rdataset->methods = &rdataset_methods;
+	rdataset->rdclass = rdclass;
+	rdataset->type = rdtype;
+	rdataset->covers = covers;
+	rdataset->ttl = ttl;
+	rdataset->trust = 0;
+	rdataset->private1 = NULL;
+	rdataset->private2 = NULL;
+	rdataset->private3 = slab + reservelen;
+
+	/*
+	 * Reset iterator state.
+	 */
+	rdataset->private4 = NULL;
+	rdataset->private5 = NULL;
+}
+
 unsigned int
 dns_rdataslab_size(unsigned char *slab, unsigned int reservelen) {
 	unsigned int count, length;