Re: [libvirt] [PATCH] Re-add use of locking with iptables/ip6tables/ebtables

A previous commit introduced use of locking with invocation of iptables in the viriptables.c module commit ba95426d6f39aec1da6e069dd7222f7a8c6a5862 Author: Serge Hallyn <serge.hallyn(a)ubuntu.com&gt; Date: Fri Nov 1 12:36:59 2013 -0500 util: use -w flag when calling iptables This only ever had effect with the virtual network driver, as it was not wired up into the nwfilter driver. Unfortunately in the firewall refactoring the use of the -w flag was accidentally lost. This patch introduces it to the virfirewall.c module so that both the virtual network and nwfilter drivers will be using it. It also ensures that the equivalent --concurrent flag to ebtables is used. --- src/util/virfirewall.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++--- src/util/viriptables.c | 2 -- 2 files changed, 63 insertions(+), 6 deletions(-) diff --git a/src/util/virfirewall.c b/src/util/virfirewall.c index bab1634..c83fdc6 100644 --- a/src/util/virfirewall.c +++ b/src/util/virfirewall.c @@ -104,6 +104,44 @@ virFirewallOnceInit(void) VIR_ONCE_GLOBAL_INIT(virFirewall) +static bool iptablesUseLock; +static bool ip6tablesUseLock; +static bool ebtablesUseLock; + +static void +virFirewallCheckUpdateLock(bool *lockflag, + const char *const*args) +{ + virCommandPtr cmd = virCommandNewArgs(args); + if (virCommandRun(cmd, NULL) < 0) { + VIR_INFO("locking not supported by %s", args[0]); + } else { + VIR_INFO("using locking for %s", args[0]); + *lockflag = true; + } + virCommandFree(cmd); +} + +static void +virFirewallCheckUpdateLocking(void) +{ + const char *iptablesArgs[] = { + IPTABLES_PATH, "-w", "-L", "-n", NULL, + }; + const char *ip6tablesArgs[] = { + IP6TABLES_PATH, "-w", "-L", "-n", NULL, + }; + const char *ebtablesArgs[] = { + EBTABLES_PATH, "--concurrent", "-L", NULL, + }; + virFirewallCheckUpdateLock(&iptablesUseLock, + iptablesArgs); + virFirewallCheckUpdateLock(&ip6tablesUseLock, + ip6tablesArgs); + virFirewallCheckUpdateLock(&ebtablesUseLock, + ebtablesArgs); +} + static int virFirewallValidateBackend(virFirewallBackend backend) { @@ -161,6 +199,9 @@ virFirewallValidateBackend(virFirewallBackend backend) } currentBackend = backend; + + virFirewallCheckUpdateLocking(); + return 0; } @@ -201,6 +242,9 @@ virFirewallPtr virFirewallNew(void) { virFirewallPtr firewall; + if (virFirewallInitialize() < 0) + return NULL; + if (VIR_ALLOC(firewall) < 0) return NULL; @@ -321,6 +365,23 @@ virFirewallAddRuleFullV(virFirewallPtr firewall, rule->queryOpaque = opaque; rule->ignoreErrors = ignoreErrors; + switch (rule->layer) { + case VIR_FIREWALL_LAYER_ETHERNET: + if (ebtablesUseLock) + ADD_ARG(rule, "--concurrent"); + break; + case VIR_FIREWALL_LAYER_IPV4: + if (iptablesUseLock) + ADD_ARG(rule, "-w"); + break; + case VIR_FIREWALL_LAYER_IPV6: + if (ip6tablesUseLock) + ADD_ARG(rule, "-w"); + break; + case VIR_FIREWALL_LAYER_LAST: + break; + } +