net: Allow netdevs to be used with 'hostfwd_add' and 'hostfwd_remove'

It does not make much sense to limit these commands to the legacy 'vlan'
concept only, they should work with the modern netdevs, too. So now
it is possible to use this command with one, two or three parameters.

With one parameter, the command installs a hostfwd rule on the default
"user" network:
    hostfwd_add tcp:...

With two parameters, the command installs a hostfwd rule on a netdev
(that's the new way of using this command):
    hostfwd_add netdev_id tcp:...

With three parameters, the command installs a rule on a 'vlan' (aka hub):
    hostfwd_add hub_id name tcp:...

Same applies to the hostfwd_remove command now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

2 files changed, 25 insertions, 12 deletions

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 6d5ebdf6ab..45eebf27e6 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1383,7 +1383,7 @@ ETEXI
     {
         .name       = "hostfwd_add",
         .args_type  = "arg1:s,arg2:s?,arg3:s?",
-        .params     = "[vlan_id name] [tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport",
+        .params     = "[hub_id name]|[netdev_id] [tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport",
         .help       = "redirect TCP or UDP connections from host to guest (requires -net user)",
         .cmd        = hmp_hostfwd_add,
     },
@@ -1398,7 +1398,7 @@ ETEXI
     {
         .name       = "hostfwd_remove",
         .args_type  = "arg1:s,arg2:s?,arg3:s?",
-        .params     = "[vlan_id name] [tcp|udp]:[hostaddr]:hostport",
+        .params     = "[hub_id name]|[netdev_id] [tcp|udp]:[hostaddr]:hostport",
         .help       = "remove host-to-guest TCP or UDP redirection",
         .cmd        = hmp_hostfwd_remove,
     },
diff --git a/net/slirp.c b/net/slirp.c
index cb8ca2312f..7044d292c8 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -405,16 +405,23 @@ error:
     return -1;
 }
 
-static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
-                                const char *stack)
+static SlirpState *slirp_lookup(Monitor *mon, const char *hub_id,
+                                const char *name)
 {
-
-    if (vlan) {
+    if (name) {
         NetClientState *nc;
-        nc = net_hub_find_client_by_name(strtol(vlan, NULL, 0), stack);
-        if (!nc) {
-            monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
-            return NULL;
+        if (hub_id) {
+            nc = net_hub_find_client_by_name(strtol(hub_id, NULL, 0), name);
+            if (!nc) {
+                monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
+                return NULL;
+            }
+        } else {
+            nc = qemu_find_netdev(name);
+            if (!nc) {
+                monitor_printf(mon, "unrecognized netdev id '%s'\n", name);
+                return NULL;
+            }
         }
         if (strcmp(nc->model, "user")) {
             monitor_printf(mon, "invalid device specified\n");
@@ -443,9 +450,12 @@ void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
     const char *arg2 = qdict_get_try_str(qdict, "arg2");
     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 
-    if (arg2) {
+    if (arg3) {
         s = slirp_lookup(mon, arg1, arg2);
         src_str = arg3;
+    } else if (arg2) {
+        s = slirp_lookup(mon, NULL, arg1);
+        src_str = arg2;
     } else {
         s = slirp_lookup(mon, NULL, NULL);
         src_str = arg1;
@@ -570,9 +580,12 @@ void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
     const char *arg2 = qdict_get_try_str(qdict, "arg2");
     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 
-    if (arg2) {
+    if (arg3) {
         s = slirp_lookup(mon, arg1, arg2);
         redir_str = arg3;
+    } else if (arg2) {
+        s = slirp_lookup(mon, NULL, arg1);
+        redir_str = arg2;
     } else {
         s = slirp_lookup(mon, NULL, NULL);
         redir_str = arg1;