+ int tr_constraint_set_validate(TR_CONSTRAINT_SET *cset)
+{
+ json_t *json = (json_t *) cset;
+ size_t i;
+ json_t *set_member;
+ if (!json_is_array(json)){
+ tr_debug("Constraint_set is not an array");
+ return 0;
+ }
+ json_array_foreach(json, i, set_member) {
+ json_t *value;
+ const char *key;
+ if (!json_is_object(set_member)) {
+ tr_debug("Constraint member at %zu is not an object\n", i);
+ return 0;
+ }
+ json_object_foreach( set_member, key, value) {
+ size_t inner_index;
+ json_t *inner_value;
+ if (!json_is_array(value)) {
+ tr_debug("Constraint type %s at index %zu in constraint set is not an array\n", key,
+ i);
+ return 0;
+ }
+ json_array_foreach(value, inner_index, inner_value) {
+ if (!json_is_string(inner_value)) {
+ tr_debug("Constraint type %s at index %zu in constraint set has non-string element %zu\n",
+ key, i, inner_index);
+ return 0;
+ }
+ }
+ }
+ }
+ return 1;
+}
+
+
+TR_CONSTRAINT_SET *tr_constraint_set_filter( TID_REQ *request,
+ TR_CONSTRAINT_SET *orig,
+ const char *constraint_type)
+{
+ json_t *orig_cset = (json_t*) orig;
+ json_t *new_cs = NULL;
+ size_t index;
+ json_t *set_member;
+ if (!tr_constraint_set_validate( (TR_CONSTRAINT_SET *) orig_cset)) {
+ tr_debug ("tr_constraint_set_filter: not a valid constraint set\n");
+ return NULL;
+ }
+ assert (new_cs = json_array());
+ json_array_foreach(orig_cset, index, set_member) {
+ if (json_object_get( set_member, constraint_type))
+ json_array_append(new_cs, set_member);
+ }
+ return (TR_CONSTRAINT_SET *) new_cs;
+}
+
+/**
+ * Within a given constraint object merge any overlapping domain or
+ * realm constraints. For example ['*','*.net'] can be simplified to
+ * ['*']
+ */
+static void merge_constraints(json_t *constraint, const char *key)
+{
+ json_t *value_1, *value_2, *constraint_array;
+ size_t index_1, index_2;
+ /*
+ * Go through the loop pairwise linear, removing elements where one
+ * element is a subset of the other. Always shrik the array from
+ * the end so that index_1 never becomes invalid (swapping if
+ * needed).
+ */
+ constraint_array = json_object_get(constraint, key);
+ if (NULL == constraint_array)
+ return;
+ json_array_foreach( constraint_array, index_1, value_1)
+ json_array_foreach( constraint_array, index_2, value_2) {
+ if (index_2 <= index_1)
+ continue;
+ if ( tr_prefix_wildcard_match( json_string_value(value_2),
+ json_string_value(value_1))) {
+ json_array_remove(constraint_array, index_2);
+ index_2--;
+ }else if (tr_prefix_wildcard_match( json_string_value(value_1),
+ json_string_value(value_2))) {
+ json_array_set(constraint_array, index_1, value_2);
+ json_array_remove(constraint_array, index_2);
+ index_2--;
+ }
+ }
+}
+
+/**
+ * Returns an array of constraint strings that is the intersection of
+ * all constraints in the constraint_set of type #type
+ */
+static json_t *constraint_intersect_internal( TR_CONSTRAINT_SET *constraints,
+ const char *constraint_type)
+{
+ json_t *constraint, *result = NULL;
+ size_t i;
+ json_array_foreach( (json_t *) constraints, i, constraint) {
+ merge_constraints( constraint, constraint_type);
+ if (NULL == result) {
+ result = json_object_get(constraint, constraint_type);
+ if (NULL != result)
+ result = json_copy(result);
+ } else {
+ json_t *intersect, *value_1, *value_2;
+ size_t index_1, index_2;
+ intersect = json_object_get(constraint, constraint_type);
+ result_loop:
+ json_array_foreach(result, index_1, value_1) {
+ json_array_foreach(intersect, index_2, value_2) {
+ if (tr_prefix_wildcard_match( json_string_value(value_1),
+ json_string_value(value_2)))
+ goto result_acceptable;
+ else if (tr_prefix_wildcard_match(json_string_value( value_2),
+ json_string_value(value_1))) {
+ json_array_set(result, index_1, value_2);
+ goto result_acceptable;
+ }
+ }
+ json_array_remove(result, index_1);
+ if (index_1 == 0)
+ goto result_loop;
+ index_1--;
+ result_acceptable: continue;
+ }
+ }
+ }
+ return result;
+}
+
+/**
+ * Return the intersection of domain and realm constraints.
+ * Return is live until #request is freed.
+ */
+TR_CONSTRAINT_SET *tr_constraint_set_intersect( TID_REQ *request,
+ TR_CONSTRAINT_SET *input)
+{
+ json_t *domain=NULL, *realm=NULL;
+ json_t *result = NULL, *result_array = NULL;
+ if (tr_constraint_set_validate(input)) {
+ domain = constraint_intersect_internal(input, "domain");
+ realm = constraint_intersect_internal(input, "realm");
+ }
+ assert(result = json_object());
+ if (domain)
+ json_object_set_new(result, "domain", domain);
+ if (realm)
+ json_object_set_new(result, "realm", realm);
+ assert(result_array = json_array());
+ json_array_append_new(result_array, result);
+ tid_req_cleanup_json( request, result_array);
+ return (TR_CONSTRAINT_SET *) result_array;
+}