diff --git a/src/include/libradius.h b/src/include/libradius.h
index 096746ab8a04..d02425044953 100644
--- a/src/include/libradius.h
+++ b/src/include/libradius.h
@@ -629,7 +629,6 @@ void		pairmemsteal(VALUE_PAIR *vp, uint8_t const *src);
 void		pairstrsteal(VALUE_PAIR *vp, char const *src);
 void		pairstrcpy(VALUE_PAIR *vp, char const * src);
 void		pairstrncpy(VALUE_PAIR *vp, char const * src, size_t len);
-int		pairdatacpy(VALUE_PAIR *vp, PW_TYPE type, value_data_t const *data, size_t len);
 void		pairsprintf(VALUE_PAIR *vp, char const * fmt, ...) CC_HINT(format (printf, 2, 3));
 void		pairmove(TALLOC_CTX *ctx, VALUE_PAIR **to, VALUE_PAIR **from);
 void		pairfilter(TALLOC_CTX *ctx, VALUE_PAIR **to, VALUE_PAIR **from,
diff --git a/src/lib/pair.c b/src/lib/pair.c
index 5b6b3bfa0faf..39c95367efd0 100644
--- a/src/lib/pair.c
+++ b/src/lib/pair.c
@@ -2107,88 +2107,6 @@ void pairstrncpy(VALUE_PAIR *vp, char const *src, size_t len)
 	pairtypeset(vp);
 }
 
-/** Copy data from one VP to another
- *
- * Allocate a new pair using da, and copy over the value from the specified vp.
- *
- * @todo Should be able to do type conversions.
- *
- * @param[in,out] vp to update.
- * @param[in] type of data represented by data.
- * @param[in] data to copy.
- * @param[in] len of data to copy.
- * @return 0 on success -1 on failure.
- */
-int pairdatacpy(VALUE_PAIR *vp, PW_TYPE type, value_data_t const *data, size_t len)
-{
-	void *old;
-	VERIFY_VP(vp);
-
-	/*
-	 *	The types have to be identical, OR the "from" type has
-	 *	to be octets.
-	 */
-	if (vp->da->type != type) {
-		/*
-		 *	Decode the octets buffer using the RADIUS decoder.
-		 */
-		if (type == PW_TYPE_OCTETS) {
-			if (data2vp(vp, NULL, NULL, NULL, vp->da, data->octets, len, len, &vp) < 0) return -1;
-			vp->type = VT_DATA;
-			return 0;
-		}
-
-		/*
-		 *	Else if the destination type is octets
-		 */
-		if (vp->da->type == PW_TYPE_OCTETS) {
-			int ret;
-			uint8_t *buff;
-			VALUE_PAIR const *pvp = vp;
-
-			buff = talloc_array(vp, uint8_t, dict_attr_sizes[type][1] + 2);
-
-			ret = rad_vp2rfc(NULL, NULL, NULL, &pvp, buff, dict_attr_sizes[type][1]);
-			if (ret < 0) return -1;
-
-			pairmemcpy(vp, buff + 2, ret - 2);
-			talloc_free(buff);
-
-			return 0;
-		}
-
-		/*
-		 *	Fixme...
-		 */
-		fr_strerror_printf("Data conversion not supported");
-		return -1;
-	}
-
-	/*
-	 *	Clear existing value if there is one
-	 */
-	memcpy(&old, &vp->data.ptr, sizeof(old));
-	talloc_free(old);
-
-	switch (vp->da->type) {
-	case PW_TYPE_TLV:
-	case PW_TYPE_OCTETS:
-		pairmemcpy(vp, data->octets, len);
-		break;
-
-	case PW_TYPE_STRING:
-		pairstrncpy(vp, data->strvalue, len);
-		break;
-
-	default:
-		memcpy(&vp->data, data, sizeof(vp->data));
-		break;
-	}
-	vp->vp_length = len;
-
-	return 0;
-}
-
 /** Print data into an "string" data type.
  *
  * @param[in,out] vp to update
diff --git a/src/lib/value.c b/src/lib/value.c
index 9697d78b009d..86cb2c7b3eae 100644
--- a/src/lib/value.c
+++ b/src/lib/value.c
@@ -1193,10 +1193,18 @@ ssize_t value_data_cast(TALLOC_CTX *ctx, value_data_t *dst,
 	return src_len;
 }
 
-ssize_t value_data_copy(TALLOC_CTX *ctx, value_data_t *dst, PW_TYPE type,
+/** Copy value data verbatim duplicating any buffers
+ *
+ * @param ctx To allocate buffers in.
+ * @param dst Where to copy value_data to.
+ * @param src_type Type of src.
+ * @param src Where to copy value_data from.
+ * @param src_len Where
+ */
+ssize_t value_data_copy(TALLOC_CTX *ctx, value_data_t *dst, PW_TYPE src_type,
 			const value_data_t *src, size_t src_len)
 {
-	switch (type) {
+	switch (src_type) {
 	default:
 		memcpy(dst, src, sizeof(*src));
 		break;
diff --git a/src/modules/rlm_cache/serialize.c b/src/modules/rlm_cache/serialize.c
index 12d91355cd6f..dc162d1250f4 100644
--- a/src/modules/rlm_cache/serialize.c
+++ b/src/modules/rlm_cache/serialize.c
@@ -139,6 +139,7 @@ int cache_deserialize(rlm_cache_entry_t *c, char *in, ssize_t inlen)
 	while (((size_t)(p - in)) < (size_t)inlen) {
 		value_pair_map_t *map = NULL;
 		VALUE_PAIR *vp = NULL;
+		ssize_t len;
 
 		q = strchr(p, '\n');
 		if (!q) break;	/* List should also be terminated with a \n */
@@ -172,10 +173,9 @@ int cache_deserialize(rlm_cache_entry_t *c, char *in, ssize_t inlen)
 		if (!tmpl_cast_in_place(map->rhs, map->lhs->tmpl_da->type, map->lhs->tmpl_da)) goto error;
 
 		vp = pairalloc(c, map->lhs->tmpl_da);
-		if (pairdatacpy(vp, map->rhs->tmpl_data_type, &map->rhs->tmpl_data_value,
-				map->rhs->tmpl_data_length) < 0) {
-			goto error;
-		}
+		len = value_data_copy(vp, &vp->data, map->rhs->tmpl_data_type,
+				      &map->rhs->tmpl_data_value, map->rhs->tmpl_data_length);
+		if (len < 0) goto error;
 
 		/*
 		 *	Pull out the special attributes, and set the