s4:ldb Add 'single-value' support to LDB.

This is currently only triggered via Samba4's schema code.

2 files changed, 52 insertions, 2 deletions

diff --git a/source4/lib/ldb/include/ldb.h b/source4/lib/ldb/include/ldb.h
index 0378697f4b..fa531b26f2 100644
--- a/source4/lib/ldb/include/ldb.h
+++ b/source4/lib/ldb/include/ldb.h
@@ -392,6 +392,11 @@ const struct ldb_dn_extended_syntax *ldb_dn_extended_syntax_by_name(struct ldb_c
  */
 #define LDB_ATTR_FLAG_UNIQUE_INDEX (1<<3)
 
+/*
+  when this is set, attempts to create two attribute values for this attribute on a single DN will return LDB_ERR_CONSTRAINT_VIOLATION
+ */
+#define LDB_ATTR_FLAG_SINGLE_VALUE (1<<4)
+
 /**
   LDAP attribute syntax for a DN
 
diff --git a/source4/lib/ldb/ldb_tdb/ldb_tdb.c b/source4/lib/ldb/ldb_tdb/ldb_tdb.c
index d4f7b452cb..e569a5a2a8 100644
--- a/source4/lib/ldb/ldb_tdb/ldb_tdb.c
+++ b/source4/lib/ldb/ldb_tdb/ldb_tdb.c
@@ -254,7 +254,7 @@ static int ltdb_add_internal(struct ldb_module *module,
 			     const struct ldb_message *msg)
 {
 	struct ldb_context *ldb = ldb_module_get_ctx(module);
-	int ret;
+	int ret, i;
 
 	ret = ltdb_check_special_dn(module, msg);
 	if (ret != LDB_SUCCESS) {
@@ -265,6 +265,24 @@ static int ltdb_add_internal(struct ldb_module *module,
 		return LDB_ERR_OPERATIONS_ERROR;
 	}
 
+	for (i=0;i<msg->num_elements;i++) {
+		struct ldb_message_element *el = &msg->elements[i];
+		const struct ldb_schema_attribute *a = ldb_schema_attribute_by_name(ldb, el->name);
+
+		if (el->num_values == 0) {
+			ldb_asprintf_errstring(ldb, "attribute %s on %s speicified, but with 0 values (illigal)", 
+					       el->name, ldb_dn_get_linearized(msg->dn));
+			return LDB_ERR_CONSTRAINT_VIOLATION;
+		}
+		if (a && a->flags & LDB_ATTR_FLAG_SINGLE_VALUE) {
+			if (el->num_values > 1) {
+				ldb_asprintf_errstring(ldb, "SINGLE-VALUE attribute %s on %s speicified more than once", 
+						       el->name, ldb_dn_get_linearized(msg->dn));
+				return LDB_ERR_CONSTRAINT_VIOLATION;
+			}
+		}
+	}
+
 	ret = ltdb_store(module, msg, TDB_INSERT);
 
 	if (ret == LDB_ERR_ENTRY_ALREADY_EXISTS) {
@@ -602,15 +620,28 @@ int ltdb_modify_internal(struct ldb_module *module,
 		struct ldb_message_element *el2;
 		struct ldb_val *vals;
 		const char *dn;
-
+		const struct ldb_schema_attribute *a = ldb_schema_attribute_by_name(ldb, el->name);
 		switch (msg->elements[i].flags & LDB_FLAG_MOD_MASK) {
 
 		case LDB_FLAG_MOD_ADD:
+			
 			/* add this element to the message. fail if it
 			   already exists */
 			idx = find_element(msg2, el->name);
 
+			if (el->num_values == 0) {
+				ldb_asprintf_errstring(ldb, "attribute %s on %s speicified, but with 0 values (illigal)", 
+						  el->name, ldb_dn_get_linearized(msg->dn));
+				return LDB_ERR_CONSTRAINT_VIOLATION;
+			}
 			if (idx == -1) {
+				if (a && a->flags & LDB_ATTR_FLAG_SINGLE_VALUE) {
+					if (el->num_values > 1) {
+						ldb_asprintf_errstring(ldb, "SINGLE-VALUE attribute %s on %s speicified more than once", 
+							       el->name, ldb_dn_get_linearized(msg->dn));
+						return LDB_ERR_CONSTRAINT_VIOLATION;
+					}
+				}
 				if (msg_add_element(ldb, msg2, el) != 0) {
 					ret = LDB_ERR_OTHER;
 					goto failed;
@@ -618,6 +649,13 @@ int ltdb_modify_internal(struct ldb_module *module,
 				continue;
 			}
 
+			/* If this is an add, then if it already
+			 * exists in the object, then we violoate the
+			 * single-value rule */
+			if (a && a->flags & LDB_ATTR_FLAG_SINGLE_VALUE) {
+				return LDB_ERR_CONSTRAINT_VIOLATION;
+			}
+
 			el2 = &msg2->elements[idx];
 
 			/* An attribute with this name already exists,
@@ -657,6 +695,13 @@ int ltdb_modify_internal(struct ldb_module *module,
 			break;
 
 		case LDB_FLAG_MOD_REPLACE:
+			if (a && a->flags & LDB_ATTR_FLAG_SINGLE_VALUE) {
+				if (el->num_values > 1) {
+					ldb_asprintf_errstring(ldb, "SINGLE-VALUE attribute %s on %s speicified more than once", 
+							       el->name, ldb_dn_get_linearized(msg->dn));
+					return LDB_ERR_CONSTRAINT_VIOLATION;
+				}
+			}
 			/* replace all elements of this attribute name with the elements
 			   listed. The attribute not existing is not an error */
 			msg_delete_attribute(module, ldb, msg2, el->name);