[couchdb] 01/01: Prevent users from modifying the special _replicator fields unless they're deleting them

[rn...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

rnewson pushed a commit to branch replicator_vdu_special_fields
in repository https://gitbox.apache.org/repos/asf/couchdb.git

commit 3eca450290776afdc81c7595e994e7fb4ceaa38c
Author: Robert Newson <rn...@apache.org>
AuthorDate: Mon Feb 28 19:04:28 2022 +0000

    Prevent users from modifying the special _replicator fields unless they're deleting them
---
 .../src/couch_replicator_js_functions.hrl            | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/couch_replicator/src/couch_replicator_js_functions.hrl b/src/couch_replicator/src/couch_replicator_js_functions.hrl
index d410433..92839d8 100644
--- a/src/couch_replicator/src/couch_replicator_js_functions.hrl
+++ b/src/couch_replicator/src/couch_replicator_js_functions.hrl
@@ -58,6 +58,26 @@
             return;
         }
 
+        // Only the replicator may change these fields, though any authorised
+        // user may delete them.
+        if (oldDoc) {
+            var protectedFields = [
+                '_replication_state',
+                '_replication_state_time',
+                '_replication_state_reason',
+                '_replication_id',
+                '_replication_stats'
+            ]
+            for (var i = 0; i < protectedFields.length; i++) {
+                var protectedField = protectedFields[i];
+                if (typeof(oldDoc[protectedField]) === 'string' &&
+                    typeof(newDoc[protectedField]) === 'string' &&
+                    oldDoc[protectedField] != newDoc[protectedField]) {
+                    reportError('Only the replicator may modify the ' + protectedField + ' field.');
+                }
+            }
+        }
+
         if (newDoc._replication_state === 'failed') {
             // Skip validation in case when we update the document with the
             // failed state. In this case it might be malformed. However,