1 files changed, 103 insertions, 0 deletions
diff --git a/src/VBox/Additions/linux/testcase/TimesyncBackdoor.c b/src/VBox/Additions/linux/testcase/TimesyncBackdoor.c
new file mode 100644
index 00000000..6f8d6eed
--- /dev/null
+++ b/src/VBox/Additions/linux/testcase/TimesyncBackdoor.c
@@ -0,0 +1,103 @@
+/** @file
+ *
+ * VirtualBox Timesync using temporary Backdoor
+ */
+
+/*
+ * Copyright (C) 2006-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include <unistd.h>
+#include <asm/io.h>
+#include <sys/time.h>
+#include <time.h>
+
+void usage()
+{
+    printf("TimesyncBackdoor [-interval <seconds>]"
+           "                 [-daemonize]"
+           "\n");
+}
+
+int main(int argc, char *argv[])
+{
+    int secInterval = 10;
+    int fDaemonize = 0;
+    int i;
+
+    for (i = 1; i < argc; i++)
+    {
+        if (strcmp(argv[i], "-interval") == 0)
+        {
+            if (argc <= i)
+            {
+                usage();
+                return 1;
+            }
+            secInterval = atoi(argv[i + 1]);
+            i++;
+        }
+        else if (strcmp(argv[i], "-daemonize") == 0)
+        {
+            fDaemonize = 1;
+        }
+        else
+        {
+            usage();
+            return 1;
+        }
+    }
+
+    /* get port IO permission */
+    if (iopl(3))
+    {
+        printf("Error: could not set IOPL to 3!\n");
+        return 1;
+    }
+
+    printf("VirtualBox timesync tool. Sync interval: %d seconds.\n", secInterval);
+
+    if (fDaemonize)
+        daemon(1, 0);
+
+    do
+    {
+        unsigned long long time;
+        /* get the high 32bit, this _must_ be done first */
+        outl(0, 0x505);
+        time = (unsigned long long)inl(0x505) << 32;
+        /* get the low 32bit */
+        outl(1, 0x505);
+        time |= inl(0x505);
+
+        /* set the system time */
+        struct timeval tv;
+        tv.tv_sec  = time / (unsigned long long)1000;
+        tv.tv_usec = (time % (unsigned long long)1000) * 1000;
+        settimeofday(&tv, NULL);
+
+    /* wait for the next run */
+        sleep(secInterval);
+
+    } while (1);
+
+    return 0;
+}