# HG changeset patch
# User John Schanck <jschanck@mozilla.com>
# Date 1786596808 0
# Node ID 9536521ea91cd4248428377e96edb926fbace3d6
# Parent  03e30a8373e4afb785fe2247a58c7f670136cbc5
Bug 2063071 - make selfserv listen on IPv6 wildcard on dual-stack hosts. r=keeler

Differential Revision: https://phabricator.services.mozilla.com/D318205

diff --git a/cmd/selfserv/selfserv.c b/cmd/selfserv/selfserv.c
--- a/cmd/selfserv/selfserv.c
+++ b/cmd/selfserv/selfserv.c
@@ -1757,16 +1757,28 @@ getBoundListenSocket(unsigned short port
     // tstclnt uses PR_GetPrefLoopbackAddrInfo to decide, if it's
     // asked to connect to localhost.
 
     prStatus = PR_GetPrefLoopbackAddrInfo(&addr, port);
     if (prStatus == PR_FAILURE) {
         addr.inet.family = PR_AF_INET;
         addr.inet.ip = PR_htonl(PR_INADDR_ANY);
         addr.inet.port = PR_htons(port);
+    } else if (addr.raw.family == PR_AF_INET6) {
+        // Check if this is a dual-stack host. If it is, listen on the IPv6
+        // wildcard, instead of loopback, so that we can receive connections
+        // from IPv4 clients.
+        PRFileDesc *ipv4_probe = PR_NewTCPSocket();
+        if (ipv4_probe) {
+            PR_Close(ipv4_probe);
+            prStatus = PR_SetNetAddr(PR_IpAddrAny, PR_AF_INET6, port, &addr);
+            if (prStatus != PR_SUCCESS) {
+                errExit("PR_SetNetAddr");
+            }
+        }
     }
 
     if (addr.inet.family == PR_AF_INET6) {
         listen_sock = PR_OpenTCPSocket(PR_AF_INET6);
     } else if (addr.inet.family == PR_AF_INET) {
         listen_sock = PR_NewTCPSocket();
     }
     if (listen_sock == NULL) {