block/backup: teach TOP to never copy unallocated regions

[qemu.git] / qemu-bridge-helper.c

diff --git a/qemu-bridge-helper.c b/qemu-bridge-helper.c
index aec5008e22c52dff54e50064caa7607df92b551c..3d50ec094c794b9c0835628f10c5b8275d94ab89 100644 (file)
--- a/qemu-bridge-helper.c
+++ b/qemu-bridge-helper.c
@@ -10,22 +10,22 @@
  *
  * This work is licensed under the terms of the GNU GPL, version 2.  See
  * the COPYING file in the top-level directory.
- *
  */
 
-#include "config-host.h"
+/*
+ * Known shortcomings:
+ * - There is no manual page
+ * - The syntax of the ACL file is not documented anywhere
+ * - parse_acl_file() doesn't report fopen() failure properly, fails
+ *   to check ferror() after fgets() failure, arbitrarily truncates
+ *   long lines, handles whitespace inconsistently, error messages
+ *   don't point to the offending file and line, errors in included
+ *   files are reported, but otherwise ignored, ...
+ */
+
+#include "qemu/osdep.h"
 
-#include <stdio.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <ctype.h>
-#include <glib.h>
 
-#include <sys/types.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/un.h>
@@ -35,7 +35,11 @@
 
 #include <linux/sockios.h>
 
-#include "qemu-queue.h"
+#ifndef SIOCBRADDIF
+#include <linux/if_bridge.h>
+#endif
+
+#include "qemu/queue.h"
 
 #include "net/tap-linux.h"
 
@@ -81,7 +85,7 @@ static int parse_acl_file(const char *filename, ACLList *acl_list)
         char *ptr = line;
         char *cmd, *arg, *argend;
 
-        while (isspace(*ptr)) {
+        while (g_ascii_isspace(*ptr)) {
             ptr++;
         }
 
@@ -98,23 +102,26 @@ static int parse_acl_file(const char *filename, ACLList *acl_list)
 
         if (arg == NULL) {
             fprintf(stderr, "Invalid config line:\n  %s\n", line);
-            fclose(f);
-            errno = EINVAL;
-            return -1;
+            goto err;
         }
 
         *arg = 0;
         arg++;
-        while (isspace(*arg)) {
+        while (g_ascii_isspace(*arg)) {
             arg++;
         }
 
         argend = arg + strlen(arg);
-        while (arg != argend && isspace(*(argend - 1))) {
+        while (arg != argend && g_ascii_isspace(*(argend - 1))) {
             argend--;
         }
         *argend = 0;
 
+        if (!g_str_equal(cmd, "include") && strlen(arg) >= IFNAMSIZ) {
+            fprintf(stderr, "name `%s' too long: %zu\n", arg, strlen(arg));
+            goto err;
+        }
+
         if (strcmp(cmd, "deny") == 0) {
             acl_rule = g_malloc(sizeof(*acl_rule));
             if (strcmp(arg, "all") == 0) {
@@ -138,15 +145,18 @@ static int parse_acl_file(const char *filename, ACLList *acl_list)
             parse_acl_file(arg, acl_list);
         } else {
             fprintf(stderr, "Unknown command `%s'\n", cmd);
-            fclose(f);
-            errno = EINVAL;
-            return -1;
+            goto err;
         }
     }
 
     fclose(f);
-
     return 0;
+
+err:
+    fclose(f);
+    errno = EINVAL;
+    return -1;
+
 }
 
 static bool has_vnet_hdr(int fd)
@@ -221,7 +231,11 @@ static int drop_privileges(void)
 int main(int argc, char **argv)
 {
     struct ifreq ifr;
-    int fd, ctlfd, unixfd = -1;
+#ifndef SIOCBRADDIF
+    unsigned long ifargs[4];
+#endif
+    int ifindex;
+    int fd = -1, ctlfd = -1, unixfd = -1;
     int use_vnet = 0;
     int mtu;
     const char *bridge = NULL;
@@ -261,6 +275,10 @@ int main(int argc, char **argv)
         usage();
         return EXIT_FAILURE;
     }
+    if (strlen(bridge) >= IFNAMSIZ) {
+        fprintf(stderr, "name `%s' too long: %zu\n", bridge, strlen(bridge));
+        return EXIT_FAILURE;
+    }
 
     /* parse default acl file */
     QSIMPLEQ_INIT(&acl_list);
@@ -359,11 +377,39 @@ int main(int argc, char **argv)
         goto cleanup;
     }
 
+    /* Linux uses the lowest enslaved MAC address as the MAC address of
+     * the bridge.  Set MAC address to a high value so that it doesn't
+     * affect the MAC address of the bridge.
+     */
+    if (ioctl(ctlfd, SIOCGIFHWADDR, &ifr) < 0) {
+        fprintf(stderr, "failed to get MAC address of device `%s': %s\n",
+                iface, strerror(errno));
+        ret = EXIT_FAILURE;
+        goto cleanup;
+    }
+    ifr.ifr_hwaddr.sa_data[0] = 0xFE;
+    if (ioctl(ctlfd, SIOCSIFHWADDR, &ifr) < 0) {
+        fprintf(stderr, "failed to set MAC address of device `%s': %s\n",
+                iface, strerror(errno));
+        ret = EXIT_FAILURE;
+        goto cleanup;
+    }
+
     /* add the interface to the bridge */
     prep_ifreq(&ifr, bridge);
-    ifr.ifr_ifindex = if_nametoindex(iface);
-
-    if (ioctl(ctlfd, SIOCBRADDIF, &ifr) == -1) {
+    ifindex = if_nametoindex(iface);
+#ifndef SIOCBRADDIF
+    ifargs[0] = BRCTL_ADD_IF;
+    ifargs[1] = ifindex;
+    ifargs[2] = 0;
+    ifargs[3] = 0;
+    ifr.ifr_data = (void *)ifargs;
+    ret = ioctl(ctlfd, SIOCDEVPRIVATE, &ifr);
+#else
+    ifr.ifr_ifindex = ifindex;
+    ret = ioctl(ctlfd, SIOCBRADDIF, &ifr);
+#endif
+    if (ret == -1) {
         fprintf(stderr, "failed to add interface `%s' to bridge `%s': %s\n",
                 iface, bridge, strerror(errno));
         ret = EXIT_FAILURE;
@@ -400,7 +446,12 @@ int main(int argc, char **argv)
     /* profit! */
 
 cleanup:
-
+    if (fd >= 0) {
+        close(fd);
+    }
+    if (ctlfd >= 0) {
+        close(ctlfd);
+    }
     while ((acl_rule = QSIMPLEQ_FIRST(&acl_list)) != NULL) {
         QSIMPLEQ_REMOVE_HEAD(&acl_list, entry);
         g_free(acl_rule);