From 3f6bd4fc2543975da76112e45601d4f5058a5176 Mon Sep 17 00:00:00 2001
From: Chen Tianjie <chentianjie.ctj@alibaba-inc.com>
Date: Thu, 21 Sep 2023 23:41:32 +0800
Subject: [PATCH] Use server.current_client to decide whether cluster commands
 should return TLS info. (#12569)

Starting a change in #12233 (released in 7.2), CLUSTER commands use client's
connection to decide whether to return TLS port or non-TLS port, but commands
called by Lua script and module's RM_Call don't have a real client with connection,
and would currently be regarded as non-TLS connections.

We can use server.current_client instead when it is available. When it is not (module calls
commands without a real client), we may see this as an undefined behavior, and return null
or default port (currently in this PR it returns default port, judged by server.tls_cluster).

(cherry picked from commit 2aad03fa399f520febb8b7db972459bc97484104)
---
 src/cluster.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/cluster.c b/src/cluster.c
index 27d109914..9cfa99a32 100644
--- a/src/cluster.c
+++ b/src/cluster.c
@@ -119,6 +119,20 @@ static inline int defaultClientPort(void) {
     return server.tls_cluster ? server.tls_port : server.port;
 }
 
+/* When a cluster command is called, we need to decide whether to return TLS info or
+ * non-TLS info by the client's connection type. However if the command is called by
+ * a Lua script or RM_call, there is no connection in the fake client, so we use 
+ * server.current_client here to get the real client if available. And if it is not 
+ * available (modules may call commands without a real client), we return the default
+ * info, which is determined by server.tls_cluster. */
+static int shouldReturnTlsInfo(void) {
+    if (server.current_client && server.current_client->conn) {
+        return connIsTLS(server.current_client->conn);
+    } else {
+        return server.tls_cluster;
+    }
+}
+
 /* Links to the next and previous entries for keys in the same slot are stored
  * in the dict entry metadata. See Slot to Key API below. */
 #define dictEntryNextInSlot(de) \
@@ -5570,7 +5584,7 @@ void addNodeToNodeReply(client *c, clusterNode *node) {
     }
 
     /* Report TLS ports to TLS client, and report non-TLS port to non-TLS client. */
-    addReplyLongLong(c, getNodeClientPort(node, connIsTLS(c->conn)));
+    addReplyLongLong(c, getNodeClientPort(node, shouldReturnTlsInfo()));
     addReplyBulkCBuffer(c, node->name, CLUSTER_NAMELEN);
 
     /* Add the additional endpoint information, this is all the known networking information
@@ -5946,7 +5960,7 @@ NULL
     } else if (!strcasecmp(c->argv[1]->ptr,"nodes") && c->argc == 2) {
         /* CLUSTER NODES */
         /* Report TLS ports to TLS client, and report non-TLS port to non-TLS client. */
-        sds nodes = clusterGenNodesDescription(c, 0, connIsTLS(c->conn));
+        sds nodes = clusterGenNodesDescription(c, 0, shouldReturnTlsInfo());
         addReplyVerbatim(c,nodes,sdslen(nodes),"txt");
         sdsfree(nodes);
     } else if (!strcasecmp(c->argv[1]->ptr,"myid") && c->argc == 2) {
@@ -6312,7 +6326,7 @@ NULL
         /* Report TLS ports to TLS client, and report non-TLS port to non-TLS client. */
         addReplyArrayLen(c,n->numslaves);
         for (j = 0; j < n->numslaves; j++) {
-            sds ni = clusterGenNodeDescription(c, n->slaves[j], connIsTLS(c->conn));
+            sds ni = clusterGenNodeDescription(c, n->slaves[j], shouldReturnTlsInfo());
             addReplyBulkCString(c,ni);
             sdsfree(ni);
         }
@@ -7438,7 +7452,7 @@ void clusterRedirectClient(client *c, clusterNode *n, int hashslot, int error_co
                error_code == CLUSTER_REDIR_ASK)
     {
         /* Report TLS ports to TLS client, and report non-TLS port to non-TLS client. */
-        int port = getNodeClientPort(n, connIsTLS(c->conn));
+        int port = getNodeClientPort(n, shouldReturnTlsInfo());
         addReplyErrorSds(c,sdscatprintf(sdsempty(),
             "-%s %d %s:%d",
             (error_code == CLUSTER_REDIR_ASK) ? "ASK" : "MOVED",