[libvirt] [RFC PATCH] network: add an option to disable dnsmasq's bind-dynamic

When building vlans on top of veth networks, dnsmasq doesn't catch DNS requests on the vlans interfaces. Allowing to disable the bind-dynamic helps this use case. --- src/conf/network_conf.c | 12 ++++++++++++ src/conf/network_conf.h | 1 + src/network/bridge_driver.c | 3 ++- 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c index f4a9df0..63e26e1 100644 --- a/src/conf/network_conf.c +++ b/src/conf/network_conf.c @@ -1987,6 +1987,7 @@ virNetworkDefParseXML(xmlXPathContextPtr ctxt) xmlNodePtr forwardNode = NULL; char *ipv6nogwStr = NULL; char *trustGuestRxFilters = NULL; + char *binddynamicStr = NULL; xmlNodePtr save = ctxt->node; xmlNodePtr bandwidthNode = NULL; xmlNodePtr vlanNode; @@ -2049,6 +2050,16 @@ virNetworkDefParseXML(xmlXPathContextPtr ctxt) VIR_FREE(trustGuestRxFilters); } + /* Default for binddynamic is on */ + def->binddynamic = true; + binddynamicStr = virXPathString("string(./@binddynamic)", ctxt); + if (binddynamicStr) { + if (STRNEQ(binddynamicStr, "no")) { + def->binddynamic = false; + } + VIR_FREE(binddynamicStr); + } + /* Parse network domain information */ def->domain = virXPathString("string(./domain[1]/@name)", ctxt); tmp = virXPathString("string(./domain[1]/@localOnly)", ctxt); @@ -2326,6 +2337,7 @@ virNetworkDefParseXML(xmlXPathContextPtr ctxt) VIR_FREE(ipNodes); VIR_FREE(portGroupNodes); VIR_FREE(ipv6nogwStr); + VIR_FREE(binddynamicStr); VIR_FREE(trustGuestRxFilters); ctxt->node = save; return NULL; diff --git a/src/conf/network_conf.h b/src/conf/network_conf.h index f69d999..163581e 100644 --- a/src/conf/network_conf.h +++ b/src/conf/network_conf.h @@ -253,6 +253,7 @@ struct _virNetworkDef { virNetDevBandwidthPtr bandwidth; virNetDevVlan vlan; int trustGuestRxFilters; /* enum virTristateBool */ + bool binddynamic; /* to force off bind_dynamic option of dnsmasq */ }; typedef struct _virNetworkObj virNetworkObj; diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index d195085..5dddc4b 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -988,7 +988,8 @@ networkDnsmasqConfContents(virNetworkObjPtr network, /* dnsmasq will *always* listen on localhost unless told otherwise */ virBufferAddLit(&configbuf, "except-interface=lo\n"); - if (dnsmasqCapsGet(caps, DNSMASQ_CAPS_BIND_DYNAMIC)) { + if (network->def->binddynamic && + dnsmasqCapsGet(caps, DNSMASQ_CAPS_BIND_DYNAMIC)) { /* using --bind-dynamic with only --interface (no * --listen-address) prevents dnsmasq from responding to dns * queries that arrive on some interface other than our bridge -- 2.1.4