util: add new "tc" layer for virFirewallCmd objects

If the layer of a virFirewallCmd is "tc", then the "tc" utility will
be executed using the arguments that had been added to the
virFirewallCmd

tc layer doesn't support auto-rollback command creation (any rollback
needs to be added manually with virFirewallAddRollbackCmd()), and also
tc layer isn't supported by the iptables backend (it would have been
straightforward to add, but the iptables backend doesn't need it, and
I didn't want to take the chance of causing a regression in that
code for no good reason).

Signed-off-by: Laine Stump <laine@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/network/network_nftables.c

@@ -73,6 +73,7 @@ VIR_ENUM_IMPL(nftablesLayer,
               "",
               "ip",
               "ip6",
+              "",
 );
 
 

src/util/virfirewall.c

@@ -47,6 +47,7 @@ VIR_ENUM_IMPL(virFirewallLayer,
               "ethernet",
               "ipv4",
               "ipv6",
+              "tc",
 );
 
 typedef struct _virFirewallGroup virFirewallGroup;
@@ -57,6 +58,7 @@ VIR_ENUM_IMPL(virFirewallLayerCommand,
               EBTABLES,
               IPTABLES,
               IP6TABLES,
+              TC,
 );
 
 struct _virFirewallCmd {
@@ -591,6 +593,7 @@ virFirewallCmdIptablesApply(virFirewall *firewall,
     case VIR_FIREWALL_LAYER_IPV6:
         virCommandAddArg(cmd, "-w");
         break;
+    case VIR_FIREWALL_LAYER_TC:
     case VIR_FIREWALL_LAYER_LAST:
         break;
     }
@@ -672,39 +675,52 @@ virFirewallCmdNftablesApply(virFirewall *firewall G_GNUC_UNUSED,
     size_t i;
     int status;
 
-    cmd = virCommandNew(NFT);
+    if (fwCmd->layer == VIR_FIREWALL_LAYER_TC) {
 
-    if ((virFirewallTransactionGetFlags(firewall) & VIR_FIREWALL_TRANSACTION_AUTO_ROLLBACK) &&
+        /* for VIR_FIREWALL_LAYER_TC, we run the 'tc' (traffic control) command with
-        fwCmd->argsLen > 1) {
+         * the supplied args.
-        /* skip any leading options to get to command verb */
+         */
-        for (i = 0; i < fwCmd->argsLen - 1; i++) {
+        cmd = virCommandNew(TC);
-            if (fwCmd->args[i][0] != '-')
-                break;
-        }
 
-        if (i + 1 < fwCmd->argsLen &&
+        /* NB: RAW commands don't support auto-rollback command creation */
-            VIR_NFTABLES_ARG_IS_CREATE(fwCmd->args[i])) {
 
-            cmdIdx = i;
+    } else {
-            objectType = fwCmd->args[i + 1];
 
-            /* we currently only handle auto-rollback for rules,
+        cmd = virCommandNew(NFT);
-             * chains, and tables, and those all can be "rolled
-             * back" by a delete command using the handle that is
-             * returned when "-ae" is added to the add/insert
-             * command.
-             */
-            if (STREQ_NULLABLE(objectType, "rule") ||
-                STREQ_NULLABLE(objectType, "chain") ||
-                STREQ_NULLABLE(objectType, "table")) {
 
-                needRollback = true;
+        if ((virFirewallTransactionGetFlags(firewall) & VIR_FIREWALL_TRANSACTION_AUTO_ROLLBACK) &&
-                /* this option to nft instructs it to add the
+            fwCmd->argsLen > 1) {
-                 * "handle" of the created object to stdout
+            /* skip any leading options to get to command verb */
+            for (i = 0; i < fwCmd->argsLen - 1; i++) {
+                if (fwCmd->args[i][0] != '-')
+                    break;
+            }
+
+            if (i + 1 < fwCmd->argsLen &&
+                VIR_NFTABLES_ARG_IS_CREATE(fwCmd->args[i])) {
+
+                cmdIdx = i;
+                objectType = fwCmd->args[i + 1];
+
+                /* we currently only handle auto-rollback for rules,
+                 * chains, and tables, and those all can be "rolled
+                 * back" by a delete command using the handle that is
+                 * returned when "-ae" is added to the add/insert
+                 * command.
                  */
-                virCommandAddArg(cmd, "-ae");
+                if (STREQ_NULLABLE(objectType, "rule") ||
+                    STREQ_NULLABLE(objectType, "chain") ||
+                    STREQ_NULLABLE(objectType, "table")) {
+
+                    needRollback = true;
+                    /* this option to nft instructs it to add the
+                     * "handle" of the created object to stdout
+                     */
+                    virCommandAddArg(cmd, "-ae");
+                }
             }
         }
+
     }
 
     for (i = 0; i < fwCmd->argsLen; i++)

src/util/virfirewall.h

@@ -39,6 +39,7 @@ typedef enum {
     VIR_FIREWALL_LAYER_ETHERNET,
     VIR_FIREWALL_LAYER_IPV4,
     VIR_FIREWALL_LAYER_IPV6,
+    VIR_FIREWALL_LAYER_TC,
 
     VIR_FIREWALL_LAYER_LAST,
 } virFirewallLayer;

src/util/virfirewalld.c

@@ -43,6 +43,7 @@ VIR_LOG_INIT("util.firewalld");
 VIR_ENUM_DECL(virFirewallLayerFirewallD);
 VIR_ENUM_IMPL(virFirewallLayerFirewallD,
               VIR_FIREWALL_LAYER_LAST,
+              "",
               "eb",
               "ipv4",
               "ipv6",