1 files changed, 204 insertions, 0 deletions
diff --git a/source4/dsdb/samdb/ldb_modules/ranged_results.c b/source4/dsdb/samdb/ldb_modules/ranged_results.c
new file mode 100644
index 0000000000..8f368b6f14
--- /dev/null
+++ b/source4/dsdb/samdb/ldb_modules/ranged_results.c
@@ -0,0 +1,204 @@
+/* 
+   ldb database library
+
+   Copyright (C) Andrew Bartlett 2007
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ *  Name: ldb
+ *
+ *  Component: ldb ranged results module
+ *
+ *  Description: munge AD-style 'ranged results' requests into
+ *  requests for all values in an attribute, then return the range to
+ *  the client.
+ *
+ *  Author: Andrew Bartlett
+ */
+
+#include "ldb_includes.h"
+
+struct rr_context {
+	struct ldb_request *orig_req;
+	struct ldb_request *down_req;
+};
+
+static int rr_search_callback(struct ldb_context *ldb, void *context, struct ldb_reply *ares) 
+{
+	struct rr_context *rr_context = talloc_get_type(context, struct rr_context);
+	struct ldb_request *orig_req = rr_context->orig_req;
+	int i, j, ret;
+	
+	if (ares->type != LDB_REPLY_ENTRY) {
+		return rr_context->orig_req->callback(ldb, rr_context->orig_req->context, ares);
+	}
+
+	/* Find those that are range requests from the attribute list */
+	for (i = 0; orig_req->op.search.attrs[i]; i++) {
+		char *p, *new_attr;
+		const char *end_str;
+		unsigned int start, end, orig_num_values;
+		struct ldb_message_element *el;
+		struct ldb_val *orig_values;
+		p = strchr(orig_req->op.search.attrs[i], ';');
+		if (!p) {
+			continue;
+		}
+		if (strncasecmp(p, ";range=", strlen(";range=")) != 0) {
+			continue;
+		}
+		if (sscanf(p, ";range=%u-*", &start) == 1) {
+			end = (unsigned int)-1;
+		} else if (sscanf(p, ";range=%u-%u", &start, &end) != 2) {
+			continue;
+		}
+		new_attr = talloc_strndup(orig_req, 
+					  orig_req->op.search.attrs[i],
+					  (unsigned int)(p-orig_req->op.search.attrs[i]));
+
+		if (!new_attr) {
+			ldb_oom(ldb);
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+		el = ldb_msg_find_element(ares->message, new_attr);
+		talloc_free(new_attr);
+		if (!el) {
+			continue;
+		}
+		if (start > end) {
+			ldb_asprintf_errstring(ldb, "range request error: start must not be greater than end");
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+		if (end >= el->num_values) {
+			/* Need to leave the requested attribute in
+			 * there (so add an empty one to match) */
+			end_str = "*";
+			end = el->num_values;
+			ret = ldb_msg_add_empty(ares->message, orig_req->op.search.attrs[i], 
+					       0, NULL);
+			if (ret != LDB_SUCCESS) {
+				return ret;
+			}
+		} else {
+			end_str = talloc_asprintf(el, "%u", end);
+		}
+		orig_values = el->values;
+		orig_num_values = el->num_values;
+
+		if ((start + end < start) || (start + end < end)) {
+			ldb_asprintf_errstring(ldb, "range request error: start or end would overflow!");
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+
+		el->values = talloc_array(el, struct ldb_val, end - start);
+		el->num_values = 0;
+
+		if (!el->values) {
+			ldb_oom(ldb);
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+		for (j=start; j < end; j++) {
+			el->values[el->num_values] = orig_values[j];
+			el->num_values++;
+		}
+		el->name = talloc_asprintf(el, "%s;Range=%u-%s", el->name, start, end_str);
+		if (!el->name) {
+			ldb_oom(ldb);
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+	}
+
+	return rr_context->orig_req->callback(ldb, rr_context->orig_req->context, ares);
+
+}
+
+/* search */
+static int rr_search(struct ldb_module *module, struct ldb_request *req)
+{
+	int i;
+	unsigned int start, end;
+	const char **new_attrs = NULL;
+	struct rr_context *context;
+	bool found_rr = false;
+
+	/* Strip the range request from the attribute */
+	for (i = 0; req->op.search.attrs && req->op.search.attrs[i]; i++) {
+		char *p;
+		new_attrs = talloc_realloc(req, new_attrs, const char *, i+2);
+		new_attrs[i] = req->op.search.attrs[i];
+		new_attrs[i+1] = NULL;
+		p = strchr(req->op.search.attrs[i], ';');
+		if (!p) {
+			continue;
+		}
+		if (strncasecmp(p, ";range=", strlen(";range=")) != 0) {
+			continue;
+		}
+		if (sscanf(p, ";range=%u-*", &start) == 1) {
+		} else if (sscanf(p, ";range=%u-%u", &start, &end) != 2) {
+			ldb_asprintf_errstring(module->ldb, "range request error: range requst malformed");
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+		if (start > end) {
+			ldb_asprintf_errstring(module->ldb, "range request error: start must not be greater than end");
+			return LDB_ERR_UNWILLING_TO_PERFORM;
+		}
+
+		found_rr = true;
+		new_attrs[i] = talloc_strndup(new_attrs, 
+					      req->op.search.attrs[i],
+					      (unsigned int)(p-req->op.search.attrs[i]));
+
+		if (!new_attrs[i]) {
+			ldb_oom(module->ldb);
+			return LDB_ERR_OPERATIONS_ERROR;
+		}
+	}
+
+	if (found_rr) {
+		int ret;
+		context = talloc(req, struct rr_context);
+		context->orig_req = req;
+		context->down_req = talloc(context, struct ldb_request);
+		*context->down_req = *req;
+		
+		context->down_req->op.search.attrs = new_attrs;
+		
+		context->down_req->callback = rr_search_callback;
+		context->down_req->context = context;
+
+		ret = ldb_next_request(module, context->down_req);
+		
+		/* We don't need to implement our own 'wait' function, so pass the handle along */
+		if (ret == LDB_SUCCESS) {
+			req->handle = context->down_req->handle;
+		}
+		return ret;
+	}
+
+	/* No change, just run the original request as if we were never here */
+	return ldb_next_request(module, req);
+}
+
+static const struct ldb_module_ops rr_ops = {
+	.name		   = "ranged_results",
+	.search            = rr_search,
+};
+
+int ldb_ranged_results_init(void)
+{
+	return ldb_register_module(&rr_ops);
+}