slirp: Bind support for host forwarding rules

Extend the hostfwd rule format so that the user can specify on which
host interface qemu should listen for incoming connections. If omitted,
binding will takes place against all interfaces.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 36 insertions, 14 deletions

diff --git a/net.c b/net.c
index 883a236638..ee321ab47f 100644
--- a/net.c
+++ b/net.c
@@ -685,7 +685,8 @@ const char *legacy_tftp_prefix;
 const char *legacy_bootp_filename;
 static VLANClientState *slirp_vc;
 
-static void slirp_hostfwd(Monitor *mon, const char *redir_str);
+static void slirp_hostfwd(Monitor *mon, const char *redir_str,
+                          int legacy_format);
 static void slirp_guestfwd(Monitor *mon, const char *config_str,
                            int legacy_format);
 
@@ -846,7 +847,8 @@ static int net_slirp_init(Monitor *mon, VLANState *vlan, const char *model,
             struct slirp_config_str *config = slirp_configs;
 
             if (config->flags & SLIRP_CFG_HOSTFWD) {
-                slirp_hostfwd(mon, config->str);
+                slirp_hostfwd(mon, config->str,
+                              config->flags & SLIRP_CFG_LEGACY);
             } else {
                 slirp_guestfwd(mon, config->str,
                                config->flags & SLIRP_CFG_LEGACY);
@@ -871,11 +873,12 @@ static int net_slirp_init(Monitor *mon, VLANState *vlan, const char *model,
     return 0;
 }
 
-void net_slirp_hostfwd_remove(Monitor *mon, const char *port_str)
+void net_slirp_hostfwd_remove(Monitor *mon, const char *src_str)
 {
+    struct in_addr host_addr = { .s_addr = INADDR_ANY };
     int host_port;
     char buf[256] = "";
-    const char *p = port_str;
+    const char *p = src_str;
     int is_udp = 0;
     int n;
 
@@ -884,7 +887,7 @@ void net_slirp_hostfwd_remove(Monitor *mon, const char *port_str)
         return;
     }
 
-    if (!port_str || !port_str[0])
+    if (!src_str || !src_str[0])
         goto fail_syntax;
 
     get_str_sep(buf, sizeof(buf), &p, ':');
@@ -897,20 +900,29 @@ void net_slirp_hostfwd_remove(Monitor *mon, const char *port_str)
         goto fail_syntax;
     }
 
+    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
+        goto fail_syntax;
+    }
+    if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
+        goto fail_syntax;
+    }
+
     host_port = atoi(p);
 
-    n = slirp_remove_hostfwd(is_udp, host_port);
+    n = slirp_remove_hostfwd(is_udp, host_addr, host_port);
 
-    monitor_printf(mon, "removed %d host forwarding rules for %s port %d\n",
-                   n, is_udp ? "udp" : "tcp", host_port);
+    monitor_printf(mon, "removed %d host forwarding rules for %s\n", n,
+                   src_str);
     return;
 
  fail_syntax:
     monitor_printf(mon, "invalid format\n");
 }
 
-static void slirp_hostfwd(Monitor *mon, const char *redir_str)
+static void slirp_hostfwd(Monitor *mon, const char *redir_str,
+                          int legacy_format)
 {
+    struct in_addr host_addr = { .s_addr = INADDR_ANY };
     struct in_addr guest_addr = { .s_addr = 0 };
     int host_port, guest_port;
     const char *p;
@@ -930,7 +942,16 @@ static void slirp_hostfwd(Monitor *mon, const char *redir_str)
         goto fail_syntax;
     }
 
-    if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
+    if (!legacy_format) {
+        if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
+            goto fail_syntax;
+        }
+        if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
+            goto fail_syntax;
+        }
+    }
+
+    if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
         goto fail_syntax;
     }
     host_port = strtol(buf, &end, 0);
@@ -950,7 +971,8 @@ static void slirp_hostfwd(Monitor *mon, const char *redir_str)
         goto fail_syntax;
     }
 
-    if (slirp_add_hostfwd(is_udp, host_port, guest_addr, guest_port) < 0) {
+    if (slirp_add_hostfwd(is_udp, host_addr, host_port,
+                          guest_addr, guest_port) < 0) {
         config_error(mon, "could not set up host forwarding rule '%s'\n",
                      redir_str);
     }
@@ -967,7 +989,7 @@ void net_slirp_hostfwd_add(Monitor *mon, const char *redir_str)
         return;
     }
 
-    slirp_hostfwd(mon, redir_str);
+    slirp_hostfwd(mon, redir_str, 0);
 }
 
 void net_slirp_redir(const char *redir_str)
@@ -977,13 +999,13 @@ void net_slirp_redir(const char *redir_str)
     if (!slirp_inited) {
         config = qemu_malloc(sizeof(*config));
         pstrcpy(config->str, sizeof(config->str), redir_str);
-        config->flags = SLIRP_CFG_HOSTFWD;
+        config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
         config->next = slirp_configs;
         slirp_configs = config;
         return;
     }
 
-    slirp_hostfwd(NULL, redir_str);
+    slirp_hostfwd(NULL, redir_str, 1);
 }
 
 #ifndef _WIN32