Re: [libvirt PATCH 08/28] util: move/rename virFirewallApplyRuleDirect to virIptablesApplyFirewallRule

On Sun, Apr 30, 2023 at 11:19:23PM -0400, Laine Stump wrote: > This is the only iptables-specific function in all of > virfirewall.c. By moving it to viriptables.c (with appropriate > renaming), and calling it indirectly through a similarly named wrapper > function in virnetfilter.c, we have made virfirewall.c backend > agnostic (the new wrapper function will soon be calling either > virIptablesApplyFirewallRule() or (to-be-created) > virNftablesApplyFirewallRule() depending on the backend chosen when > creating the virFirewall object). > > Signed-off-by: Laine Stump <laine(a)redhat.com&gt; > --- > src/libvirt_private.syms | 2 ++ > src/util/virfirewall.c | 72 ++----------------------------------- > src/util/viriptables.c | 78 ++++++++++++++++++++++++++++++++++++++++ > src/util/viriptables.h | 6 ++++ > src/util/virnetfilter.c | 19 ++++++++++ > src/util/virnetfilter.h | 3 ++ I don't much like this split of responsibilities. With the current codebase * virfirewall.c is the low level transactional interface for interacting with firewalls. * viriptables.c is a medium level interface providing helpers needed by the network bridge driver The viriptables.c file probably ought not to even be located in the src/util directory. Its API is inherantly tied to the bridge driver, so ought to be moved to src/network/bridge_iptables.c I think. IOW, we have a clean flow from high level to low level of bridge_driver.c -> viriptables.c -> virfirewall.c and nwfilter_driver.c -> nwfilter_ebiptables_driver.c -> virfirewall.c After this change, AFAICT we have dependancy loops * virfirewall.c is the low level transactional interface for interacting with firwalls * viriptables.c is a medium level interface providing helpers needed by the netfilter APIs, and also helpers needed by virfirewall.c * virnetfilter.c is a slightly higher level inteface providing helpers needed by the bridge interface IOW, AFAICT we now have bridge-driver.c -> virnetfilter.c -> viriptables.c -> virfirewall.c ^ | | | \-----------------/ and nwfilter_driver.c -> nwfilter_ebiptables_driver.c -> virfirewall.c -> viriptables.c

> 6 files changed, 110 insertions(+), 70 deletions(-) > > diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms > index 11b84a866a..cf68e4c942 100644 > --- a/src/libvirt_private.syms > +++ b/src/libvirt_private.syms > @@ -2550,6 +2550,7 @@ virInitctlSetRunLevel; > iptablesAddOutputFixUdpChecksum; > iptablesRemoveOutputFixUdpChecksum; > iptablesSetupPrivateChains; > +virIptablesApplyFirewallRule; > > > # util/viriscsi.h > @@ -2949,6 +2950,7 @@ virNetfilterAddTcpInput; > virNetfilterAddTcpOutput; > virNetfilterAddUdpInput; > virNetfilterAddUdpOutput; > +virNetfilterApplyFirewallRule; > virNetfilterRemoveDontMasquerade; > virNetfilterRemoveForwardAllowCross; > virNetfilterRemoveForwardAllowIn; > diff --git a/src/util/virfirewall.c b/src/util/virfirewall.c > index e3ba8f7846..6603fd6341 100644 > --- a/src/util/virfirewall.c > +++ b/src/util/virfirewall.c > @@ -24,6 +24,7 @@ > > #include "virfirewall.h" > #include "virfirewalld.h" > +#include "virnetfilter.h" > #include "viralloc.h" > #include "virerror.h" > #include "vircommand.h" > @@ -37,14 +38,6 @@ VIR_LOG_INIT("util.firewall"); > > typedef struct _virFirewallGroup virFirewallGroup; > > -VIR_ENUM_DECL(virFirewallLayerCommand); > -VIR_ENUM_IMPL(virFirewallLayerCommand, > - VIR_FIREWALL_LAYER_LAST, > - EBTABLES, > - IPTABLES, > - IP6TABLES, > -); > - > struct _virFirewallRule { > virFirewallLayer layer; > > @@ -500,67 +493,6 @@ virFirewallRuleToString(const char *cmd, > } > > > -static int > -virFirewallApplyRuleDirect(virFirewallRule *rule, > - char **output) > -{ > - size_t i; > - const char *bin = virFirewallLayerCommandTypeToString(rule->layer); > - g_autoptr(virCommand) cmd = NULL; > - g_autofree char *cmdStr = NULL; > - int status; > - g_autofree char *error = NULL; > - > - if (!bin) { > - virReportError(VIR_ERR_INTERNAL_ERROR, > - _("Unknown firewall layer %1$d"), > - rule->layer); > - return -1; > - } > - > - cmd = virCommandNewArgList(bin, NULL); > - > - /* lock to assure nobody else is messing with the tables while we are */ > - switch (rule->layer) { > - case VIR_FIREWALL_LAYER_ETHERNET: > - virCommandAddArg(cmd, "--concurrent"); > - break; > - case VIR_FIREWALL_LAYER_IPV4: > - case VIR_FIREWALL_LAYER_IPV6: > - virCommandAddArg(cmd, "-w"); > - break; > - case VIR_FIREWALL_LAYER_LAST: > - break; > - } > - > - for (i = 0; i < rule->argsLen; i++) > - virCommandAddArg(cmd, rule->args[i]); > - > - cmdStr = virCommandToString(cmd, false); > - VIR_INFO("Applying rule '%s'", NULLSTR(cmdStr)); > - > - virCommandSetOutputBuffer(cmd, output); > - virCommandSetErrorBuffer(cmd, &error); > - > - if (virCommandRun(cmd, &status) < 0) > - return -1; > - > - if (status != 0) { > - if (virFirewallRuleGetIgnoreErrors(rule)) { > - VIR_DEBUG("Ignoring error running command"); > - } else { > - virReportError(VIR_ERR_INTERNAL_ERROR, > - _("Failed to apply firewall rules %1$s: %2$s"), > - NULLSTR(cmdStr), NULLSTR(error)); > - VIR_FREE(*output); > - return -1; > - } > - } > - > - return 0; > -} > - > - > static int > virFirewallApplyRule(virFirewall *firewall, > virFirewallRule *rule) > @@ -568,7 +500,7 @@ virFirewallApplyRule(virFirewall *firewall, > g_autofree char *output = NULL; > g_auto(GStrv) lines = NULL; > > - if (virFirewallApplyRuleDirect(rule, &output) < 0) > + if (virNetfilterApplyFirewallRule(firewall, rule, &output) < 0) > return -1; > > if (rule->queryCB && output) { > diff --git a/src/util/viriptables.c b/src/util/viriptables.c > index a0c35887c5..9c7f7790c4 100644 > --- a/src/util/viriptables.c > +++ b/src/util/viriptables.c > @@ -31,6 +31,8 @@ > #include "viriptables.h" > #include "virfirewalld.h" > #include "virerror.h" > +#include "viralloc.h" > +#include "vircommand.h" > #include "virlog.h" > #include "virhash.h" > #include "virenum.h" > @@ -40,6 +42,19 @@ VIR_LOG_INIT("util.iptables"); > #define VIR_FROM_THIS VIR_FROM_NONE > > > +/* iptables backend uses a different program for each layer. This > + * gives us a convenient function for converting VIR_FIREWALL_LAYER_* > + * enum from a virFirewallRule into a binary name. > + */ > +VIR_ENUM_DECL(virIptablesLayerCommand); > +VIR_ENUM_IMPL(virIptablesLayerCommand, > + VIR_FIREWALL_LAYER_LAST, > + EBTABLES, > + IPTABLES, > + IP6TABLES, > +); > + > + > VIR_ENUM_DECL(virIptablesAction); > VIR_ENUM_IMPL(virIptablesAction, > VIR_FIREWALL_ACTION_LAST, > @@ -49,6 +64,69 @@ VIR_ENUM_IMPL(virIptablesAction, > ); > > > +int > +virIptablesApplyFirewallRule(virFirewall *firewall G_GNUC_UNUSED, > + virFirewallRule *rule, > + char **output) > +{ > + virFirewallLayer layer = virFirewallRuleGetLayer(rule); > + const char *bin = virIptablesLayerCommandTypeToString(layer); > + g_autoptr(virCommand) cmd = NULL; > + g_autofree char *cmdStr = NULL; > + g_autofree char *error = NULL; > + size_t i, count; > + int status; > + > + if (!bin) { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Unknown firewall layer %1$d"), layer); > + return -1; > + } > + > + cmd = virCommandNewArgList(bin, NULL); > + > + /* lock to assure nobody else is messing with the tables while we are */ > + switch (layer) { > + case VIR_FIREWALL_LAYER_ETHERNET: > + virCommandAddArg(cmd, "--concurrent"); > + break; > + case VIR_FIREWALL_LAYER_IPV4: > + case VIR_FIREWALL_LAYER_IPV6: > + virCommandAddArg(cmd, "-w"); > + break; > + case VIR_FIREWALL_LAYER_LAST: > + break; > + } > + > + count = virFirewallRuleGetArgCount(rule); > + for (i = 0; i < count; i++) > + virCommandAddArg(cmd, virFirewallRuleGetArg(rule, i)); > + > + cmdStr = virCommandToString(cmd, false); > + VIR_INFO("Applying rule '%s'", NULLSTR(cmdStr)); > + > + virCommandSetOutputBuffer(cmd, output); > + virCommandSetErrorBuffer(cmd, &error); > + > + if (virCommandRun(cmd, &status) < 0) > + return -1; > + > + if (status != 0) { > + if (virFirewallRuleGetIgnoreErrors(rule)) { > + VIR_DEBUG("Ignoring error running command"); > + } else { > + virReportError(VIR_ERR_INTERNAL_ERROR, > + _("Failed to apply firewall rules %1$s: %2$s"), > + NULLSTR(cmdStr), NULLSTR(error)); > + VIR_FREE(*output); > + return -1; > + } > + } > + > + return 0; > +} > + > + > typedef struct { > const char *parent; > const char *child; > diff --git a/src/util/viriptables.h b/src/util/viriptables.h > index 17f43a8fa8..990cb2e25d 100644 > --- a/src/util/viriptables.h > +++ b/src/util/viriptables.h > @@ -24,6 +24,12 @@ > #include "virfirewall.h" > #include "virnetfilter.h" > > +/* virIptablesApplyFirewallRule should be called only from virnetfilter.c */ > +int > +virIptablesApplyFirewallRule(virFirewall *firewall, > + virFirewallRule *rule, > + char **output); > + > /* These functions are (currently) called directly from the consumer > * (e.g. the network driver), and only when the iptables backend is > * selected. (Possibly/probably functions should be added to the > diff --git a/src/util/virnetfilter.c b/src/util/virnetfilter.c > index 10c1a54e26..ba0f292ea9 100644 > --- a/src/util/virnetfilter.c > +++ b/src/util/virnetfilter.c > @@ -44,6 +44,25 @@ VIR_LOG_INIT("util.netfilter"); > #define VIR_FROM_THIS VIR_FROM_NONE > > > +/** > + * virNetfilterApplyFirewallRule: > + * @fw: the virFirewall this rule is part of (currently unused) > + * @rule: this particular rule > + * @ignoreErrors: true if errors should be ignored > + * @output: everything that appears on stdout as a result of applying the rule > + * > + * Applies @rule to the host's network filtering. returns 0 on success > + * -1 on failure. > + */ > +int > +virNetfilterApplyFirewallRule(virFirewall *fw, > + virFirewallRule *rule, > + char **output) > +{ > + return virIptablesApplyFirewallRule(fw, rule, output); > +} > + > + > /** > * virNetfilterAddTcpInput: > * @ctx: pointer to the IP table context > diff --git a/src/util/virnetfilter.h b/src/util/virnetfilter.h > index b515512ad7..eff047cde0 100644 > --- a/src/util/virnetfilter.h > +++ b/src/util/virnetfilter.h > @@ -30,6 +30,9 @@ > #define VIR_NETFILTER_FWD_X_CHAIN "LIBVIRT_FWX" > #define VIR_NETFILTER_NAT_POSTROUTE_CHAIN "LIBVIRT_PRT" > > +int virNetfilterApplyFirewallRule (virFirewall *fw, > + virFirewallRule *rule, > + char **output); > void virNetfilterAddTcpInput (virFirewall *fw, > virFirewallLayer layer, > const char *iface, > -- > 2.39.2 > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|