1 files changed, 399 insertions, 0 deletions
diff --git a/src/VBox/Main/src-server/linux/USBProxyBackendLinux.cpp b/src/VBox/Main/src-server/linux/USBProxyBackendLinux.cpp
new file mode 100644
index 00000000..0347f438
--- /dev/null
+++ b/src/VBox/Main/src-server/linux/USBProxyBackendLinux.cpp
@@ -0,0 +1,399 @@
+/* $Id: USBProxyBackendLinux.cpp $ */
+/** @file
+ * VirtualBox USB Proxy Service, Linux Specialization.
+ */
+
+/*
+ * Copyright (C) 2005-2022 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
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#define LOG_GROUP LOG_GROUP_MAIN_USBPROXYBACKEND
+#include "USBProxyService.h"
+#include "USBGetDevices.h"
+#include "LoggingNew.h"
+
+#include <VBox/usb.h>
+#include <VBox/usblib.h>
+#include <iprt/errcore.h>
+
+#include <iprt/string.h>
+#include <iprt/alloc.h>
+#include <iprt/assert.h>
+#include <iprt/ctype.h>
+#include <iprt/dir.h>
+#include <iprt/env.h>
+#include <iprt/file.h>
+#include <iprt/errcore.h>
+#include <iprt/mem.h>
+#include <iprt/param.h>
+#include <iprt/path.h>
+#include <iprt/pipe.h>
+#include <iprt/stream.h>
+#include <iprt/linux/sysfs.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/statfs.h>
+#include <sys/poll.h>
+#ifdef VBOX_WITH_LINUX_COMPILER_H
+# include <linux/compiler.h>
+#endif
+#include <linux/usbdevice_fs.h>
+
+
+/**
+ * Initialize data members.
+ */
+USBProxyBackendLinux::USBProxyBackendLinux()
+    : USBProxyBackend(), mhFile(NIL_RTFILE), mhWakeupPipeR(NIL_RTPIPE), mhWakeupPipeW(NIL_RTPIPE), mpWaiter(NULL)
+{
+    LogFlowThisFunc(("\n"));
+}
+
+
+/**
+ * Stop all service threads and free the device chain.
+ */
+USBProxyBackendLinux::~USBProxyBackendLinux()
+{
+    LogFlowThisFunc(("\n"));
+}
+
+/**
+ * Initializes the object (called right after construction).
+ *
+ * @returns VBox status code.
+ */
+int USBProxyBackendLinux::init(USBProxyService *pUsbProxyService, const com::Utf8Str &strId,
+                              const com::Utf8Str &strAddress, bool fLoadingSettings)
+{
+    USBProxyBackend::init(pUsbProxyService, strId, strAddress, fLoadingSettings);
+
+    unconst(m_strBackend) = Utf8Str("host");
+
+    const char *pcszDevicesRoot;
+    int rc = USBProxyLinuxChooseMethod(&mUsingUsbfsDevices, &pcszDevicesRoot);
+    if (RT_SUCCESS(rc))
+    {
+        mDevicesRoot = pcszDevicesRoot;
+        rc = mUsingUsbfsDevices ? initUsbfs() : initSysfs();
+        /* For the day when we have VBoxSVC release logging... */
+        LogRel((RT_SUCCESS(rc) ? "Successfully initialised host USB using %s\n"
+                               : "Failed to initialise host USB using %s\n",
+                mUsingUsbfsDevices ? "USBFS" : "sysfs"));
+    }
+
+    return rc;
+}
+
+void USBProxyBackendLinux::uninit()
+{
+    /*
+     * Stop the service.
+     */
+    if (isActive())
+        stop();
+
+    /*
+     * Free resources.
+     */
+    doUsbfsCleanupAsNeeded();
+#ifdef VBOX_USB_WITH_SYSFS
+    if (mpWaiter)
+        delete mpWaiter;
+#endif
+
+    USBProxyBackend::uninit();
+}
+
+
+/**
+ * Initialization routine for the usbfs based operation.
+ *
+ * @returns iprt status code.
+ */
+int USBProxyBackendLinux::initUsbfs(void)
+{
+    Assert(mUsingUsbfsDevices);
+
+    /*
+     * Open the devices file.
+     */
+    int rc;
+    char *pszDevices = RTPathJoinA(mDevicesRoot.c_str(), "devices");
+    if (pszDevices)
+    {
+        rc = RTFileOpen(&mhFile, pszDevices, RTFILE_O_READ | RTFILE_O_OPEN | RTFILE_O_DENY_NONE);
+        if (RT_SUCCESS(rc))
+        {
+            rc = RTPipeCreate(&mhWakeupPipeR, &mhWakeupPipeW, 0 /*fFlags*/);
+            if (RT_SUCCESS(rc))
+            {
+                /*
+                 * Start the poller thread.
+                 */
+                rc = start();
+                if (RT_SUCCESS(rc))
+                {
+                    RTStrFree(pszDevices);
+                    LogFlowThisFunc(("returns successfully\n"));
+                    return VINF_SUCCESS;
+                }
+
+                RTPipeClose(mhWakeupPipeR);
+                RTPipeClose(mhWakeupPipeW);
+                mhWakeupPipeW = mhWakeupPipeR = NIL_RTPIPE;
+            }
+            else
+                Log(("USBProxyBackendLinux::USBProxyBackendLinux: RTFilePipe failed with rc=%Rrc\n", rc));
+            RTFileClose(mhFile);
+        }
+
+        RTStrFree(pszDevices);
+    }
+    else
+    {
+        rc = VERR_NO_MEMORY;
+        Log(("USBProxyBackendLinux::USBProxyBackendLinux: out of memory!\n"));
+    }
+
+    LogFlowThisFunc(("returns failure!!! (rc=%Rrc)\n", rc));
+    return rc;
+}
+
+
+/**
+ * Initialization routine for the sysfs based operation.
+ *
+ * @returns iprt status code
+ */
+int USBProxyBackendLinux::initSysfs(void)
+{
+    Assert(!mUsingUsbfsDevices);
+
+#ifdef VBOX_USB_WITH_SYSFS
+    try
+    {
+        mpWaiter = new VBoxMainHotplugWaiter(mDevicesRoot.c_str());
+    }
+    catch(std::bad_alloc &e)
+    {
+        return VERR_NO_MEMORY;
+    }
+    int rc = mpWaiter->getStatus();
+    if (RT_SUCCESS(rc) || rc == VERR_TIMEOUT || rc == VERR_TRY_AGAIN)
+        rc = start();
+    else if (rc == VERR_NOT_SUPPORTED)
+        /* This can legitimately happen if hal or DBus are not running, but of
+         * course we can't start in this case. */
+        rc = VINF_SUCCESS;
+    return rc;
+
+#else  /* !VBOX_USB_WITH_SYSFS */
+    return VERR_NOT_IMPLEMENTED;
+#endif /* !VBOX_USB_WITH_SYSFS */
+}
+
+
+/**
+ * If any Usbfs-related resources are currently allocated, then free them
+ * and mark them as freed.
+ */
+void USBProxyBackendLinux::doUsbfsCleanupAsNeeded()
+{
+    /*
+     * Free resources.
+     */
+    if (mhFile != NIL_RTFILE)
+        RTFileClose(mhFile);
+    mhFile = NIL_RTFILE;
+
+    if (mhWakeupPipeR != NIL_RTPIPE)
+        RTPipeClose(mhWakeupPipeR);
+    if (mhWakeupPipeW != NIL_RTPIPE)
+        RTPipeClose(mhWakeupPipeW);
+    mhWakeupPipeW = mhWakeupPipeR = NIL_RTPIPE;
+}
+
+
+int USBProxyBackendLinux::captureDevice(HostUSBDevice *aDevice)
+{
+    AssertReturn(aDevice, VERR_GENERAL_FAILURE);
+    AssertReturn(!aDevice->isWriteLockOnCurrentThread(), VERR_GENERAL_FAILURE);
+
+    AutoReadLock devLock(aDevice COMMA_LOCKVAL_SRC_POS);
+    LogFlowThisFunc(("aDevice=%s\n", aDevice->i_getName().c_str()));
+
+    /*
+     * Don't think we need to do anything when the device is held... fake it.
+     */
+    Assert(aDevice->i_getUnistate() == kHostUSBDeviceState_Capturing);
+    devLock.release();
+    interruptWait();
+
+    return VINF_SUCCESS;
+}
+
+
+int USBProxyBackendLinux::releaseDevice(HostUSBDevice *aDevice)
+{
+    AssertReturn(aDevice, VERR_GENERAL_FAILURE);
+    AssertReturn(!aDevice->isWriteLockOnCurrentThread(), VERR_GENERAL_FAILURE);
+
+    AutoReadLock devLock(aDevice COMMA_LOCKVAL_SRC_POS);
+    LogFlowThisFunc(("aDevice=%s\n", aDevice->i_getName().c_str()));
+
+    /*
+     * We're not really holding it atm., just fake it.
+     */
+    Assert(aDevice->i_getUnistate() == kHostUSBDeviceState_ReleasingToHost);
+    devLock.release();
+    interruptWait();
+
+    return VINF_SUCCESS;
+}
+
+
+/**
+ * A device was added, we need to adjust mUdevPolls.
+ */
+void USBProxyBackendLinux::deviceAdded(ComObjPtr<HostUSBDevice> &aDevice, PUSBDEVICE pDev)
+{
+    AssertReturnVoid(aDevice);
+    AssertReturnVoid(!aDevice->isWriteLockOnCurrentThread());
+    AutoReadLock devLock(aDevice COMMA_LOCKVAL_SRC_POS);
+    if (pDev->enmState == USBDEVICESTATE_USED_BY_HOST)
+    {
+        LogRel(("USBProxyBackendLinux: Device %04x:%04x (%s) isn't accessible. giving udev a few seconds to fix this...\n",
+                pDev->idVendor, pDev->idProduct, pDev->pszAddress));
+        mUdevPolls = 10; /* (10 * 500ms = 5s) */
+    }
+
+    devLock.release();
+}
+
+
+bool USBProxyBackendLinux::isFakeUpdateRequired()
+{
+    return true;
+}
+
+int USBProxyBackendLinux::wait(RTMSINTERVAL aMillies)
+{
+    int rc;
+    if (mUsingUsbfsDevices)
+        rc = waitUsbfs(aMillies);
+    else
+        rc = waitSysfs(aMillies);
+    return rc;
+}
+
+
+/** String written to the wakeup pipe. */
+#define WAKE_UP_STRING      "WakeUp!"
+/** Length of the string written. */
+#define WAKE_UP_STRING_LEN  ( sizeof(WAKE_UP_STRING) - 1 )
+
+int USBProxyBackendLinux::waitUsbfs(RTMSINTERVAL aMillies)
+{
+    struct pollfd PollFds[2];
+
+    /* Cap the wait interval if we're polling for udevd changing device permissions. */
+    if (aMillies > 500 && mUdevPolls > 0)
+    {
+        mUdevPolls--;
+        aMillies = 500;
+    }
+
+    RT_ZERO(PollFds);
+    PollFds[0].fd        = (int)RTFileToNative(mhFile);
+    PollFds[0].events    = POLLIN;
+    PollFds[1].fd        = (int)RTPipeToNative(mhWakeupPipeR);
+    PollFds[1].events    = POLLIN | POLLERR | POLLHUP;
+
+    int rc = poll(&PollFds[0], 2, aMillies);
+    if (rc == 0)
+        return VERR_TIMEOUT;
+    if (rc > 0)
+    {
+        /* drain the pipe */
+        if (PollFds[1].revents & POLLIN)
+        {
+            char szBuf[WAKE_UP_STRING_LEN];
+            rc = RTPipeReadBlocking(mhWakeupPipeR, szBuf, sizeof(szBuf), NULL);
+            AssertRC(rc);
+        }
+        return VINF_SUCCESS;
+    }
+    return RTErrConvertFromErrno(errno);
+}
+
+
+int USBProxyBackendLinux::waitSysfs(RTMSINTERVAL aMillies)
+{
+#ifdef VBOX_USB_WITH_SYSFS
+    int rc = mpWaiter->Wait(aMillies);
+    if (rc == VERR_TRY_AGAIN)
+    {
+        RTThreadYield();
+        rc = VINF_SUCCESS;
+    }
+    return rc;
+#else  /* !VBOX_USB_WITH_SYSFS */
+    return USBProxyService::wait(aMillies);
+#endif /* !VBOX_USB_WITH_SYSFS */
+}
+
+
+int USBProxyBackendLinux::interruptWait(void)
+{
+    AssertReturn(!isWriteLockOnCurrentThread(), VERR_GENERAL_FAILURE);
+
+    AutoReadLock alock(this COMMA_LOCKVAL_SRC_POS);
+#ifdef VBOX_USB_WITH_SYSFS
+    LogFlowFunc(("mUsingUsbfsDevices=%d\n", mUsingUsbfsDevices));
+    if (!mUsingUsbfsDevices)
+    {
+        mpWaiter->Interrupt();
+        LogFlowFunc(("Returning VINF_SUCCESS\n"));
+        return VINF_SUCCESS;
+    }
+#endif /* VBOX_USB_WITH_SYSFS */
+    int rc = RTPipeWriteBlocking(mhWakeupPipeW, WAKE_UP_STRING, WAKE_UP_STRING_LEN, NULL);
+    if (RT_SUCCESS(rc))
+        RTPipeFlush(mhWakeupPipeW);
+    LogFlowFunc(("returning %Rrc\n", rc));
+    return rc;
+}
+
+
+PUSBDEVICE USBProxyBackendLinux::getDevices(void)
+{
+    return USBProxyLinuxGetDevices(mDevicesRoot.c_str(), !mUsingUsbfsDevices);
+}