/* $Id: VBoxServiceAutoMount.cpp 69149 2017-10-20 14:53:19Z vboxsync $ */ /** @file * VBoxService - Auto-mounting for Shared Folders, only Linux & Solaris atm. */ /* * Copyright (C) 2010-2016 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. */ /** @page pg_vgsvc_automount VBoxService - Shared Folder Automounter * * The Shared Folder Automounter subservice mounts shared folders upon request * from the host. * * This retrieves shared folder automount requests from Main via the VMMDev. * The current implemention only does this once, for some inexplicable reason, * so the run-time addition of automounted shared folders are not heeded. * * This subservice is only used on linux and solaris. On Windows the current * thinking is this is better of done from VBoxTray, some one argue that for * drive letter assigned shared folders it would be better to do some magic here * (obviously not involving NDAddConnection). * */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #include #include #include #include #include #include #include #include "VBoxServiceInternal.h" #include "VBoxServiceUtils.h" #include #include #include #ifdef RT_OS_SOLARIS # include # include # include #else # include # include #endif #include RT_C_DECLS_BEGIN #include "../../linux/sharedfolders/vbsfmount.h" RT_C_DECLS_END #ifdef RT_OS_SOLARIS # define VBOXSERVICE_AUTOMOUNT_DEFAULT_DIR "/mnt" #else # define VBOXSERVICE_AUTOMOUNT_DEFAULT_DIR "/media" #endif #ifndef _PATH_MOUNTED # ifdef RT_OS_SOLARIS # define _PATH_MOUNTED "/etc/mnttab" # else # define _PATH_MOUNTED "/etc/mtab" # endif #endif /********************************************************************************************************************************* * Global Variables * *********************************************************************************************************************************/ /** The semaphore we're blocking on. */ static RTSEMEVENTMULTI g_AutoMountEvent = NIL_RTSEMEVENTMULTI; /** The Shared Folders service client ID. */ static uint32_t g_SharedFoldersSvcClientID = 0; /** * @interface_method_impl{VBOXSERVICE,pfnInit} */ static DECLCALLBACK(int) vbsvcAutoMountInit(void) { VGSvcVerbose(3, "vbsvcAutoMountInit\n"); int rc = RTSemEventMultiCreate(&g_AutoMountEvent); AssertRCReturn(rc, rc); rc = VbglR3SharedFolderConnect(&g_SharedFoldersSvcClientID); if (RT_SUCCESS(rc)) { VGSvcVerbose(3, "vbsvcAutoMountInit: Service Client ID: %#x\n", g_SharedFoldersSvcClientID); } else { /* If the service was not found, we disable this service without causing VBoxService to fail. */ if (rc == VERR_HGCM_SERVICE_NOT_FOUND) /* Host service is not available. */ { VGSvcVerbose(0, "vbsvcAutoMountInit: Shared Folders service is not available\n"); rc = VERR_SERVICE_DISABLED; } else VGSvcError("Control: Failed to connect to the Shared Folders service! Error: %Rrc\n", rc); RTSemEventMultiDestroy(g_AutoMountEvent); g_AutoMountEvent = NIL_RTSEMEVENTMULTI; } return rc; } /** * @todo Integrate into RTFsQueryMountpoint()? */ static bool vbsvcAutoMountShareIsMounted(const char *pszShare, char *pszMountPoint, size_t cbMountPoint) { AssertPtrReturn(pszShare, VERR_INVALID_PARAMETER); AssertPtrReturn(pszMountPoint, VERR_INVALID_PARAMETER); AssertReturn(cbMountPoint, VERR_INVALID_PARAMETER); bool fMounted = false; /** @todo What to do if we have a relative path in mtab instead * of an absolute one ("temp" vs. "/media/temp")? * procfs contains the full path but not the actual share name ... * FILE *pFh = setmntent("/proc/mounts", "r+t"); */ #ifdef RT_OS_SOLARIS FILE *pFh = fopen(_PATH_MOUNTED, "r"); if (!pFh) VGSvcError("vbsvcAutoMountShareIsMounted: Could not open mount tab '%s'!\n", _PATH_MOUNTED); else { mnttab mntTab; while ((getmntent(pFh, &mntTab))) { if (!RTStrICmp(mntTab.mnt_special, pszShare)) { fMounted = RTStrPrintf(pszMountPoint, cbMountPoint, "%s", mntTab.mnt_mountp) ? true : false; break; } } fclose(pFh); } #else FILE *pFh = setmntent(_PATH_MOUNTED, "r+t"); /** @todo r=bird: why open it for writing? (the '+') */ if (pFh == NULL) VGSvcError("vbsvcAutoMountShareIsMounted: Could not open mount tab '%s'!\n", _PATH_MOUNTED); else { mntent *pMntEnt; while ((pMntEnt = getmntent(pFh))) { if (!RTStrICmp(pMntEnt->mnt_fsname, pszShare)) { fMounted = RTStrPrintf(pszMountPoint, cbMountPoint, "%s", pMntEnt->mnt_dir) ? true : false; break; } } endmntent(pFh); } #endif VGSvcVerbose(4, "vbsvcAutoMountShareIsMounted: Share '%s' at mount point '%s' = %s\n", pszShare, fMounted ? pszMountPoint : "", fMounted ? "Yes" : "No"); return fMounted; } /** * Unmounts a shared folder. * * @returns VBox status code * @param pszMountPoint The shared folder mount point. */ static int vbsvcAutoMountUnmount(const char *pszMountPoint) { AssertPtrReturn(pszMountPoint, VERR_INVALID_PARAMETER); int rc = VINF_SUCCESS; uint8_t uTries = 0; int r; while (uTries++ < 3) { r = umount(pszMountPoint); if (r == 0) break; /** @todo r=bird: Why do sleep 5 seconds after the final retry? * May also be a good idea to check for EINVAL or other signs that someone * else have already unmounted the share. */ RTThreadSleep(5000); /* Wait a while ... */ } if (r == -1) /** @todo r=bird: RTThreadSleep set errno. */ rc = RTErrConvertFromErrno(errno); return rc; } /** * Prepares a mount point (create it, set group and mode). * * @returns VBox status code * @param pszMountPoint The mount point. * @param pszShareName Unused. * @param pOpts For getting the group ID. */ static int vbsvcAutoMountPrepareMountPoint(const char *pszMountPoint, const char *pszShareName, vbsf_mount_opts *pOpts) { AssertPtrReturn(pOpts, VERR_INVALID_PARAMETER); AssertPtrReturn(pszMountPoint, VERR_INVALID_PARAMETER); AssertPtrReturn(pszShareName, VERR_INVALID_PARAMETER); RTFMODE fMode = RTFS_UNIX_IRWXU | RTFS_UNIX_IRWXG; /* Owner (=root) and the group (=vboxsf) have full access. */ int rc = RTDirCreateFullPath(pszMountPoint, fMode); if (RT_SUCCESS(rc)) { rc = RTPathSetOwnerEx(pszMountPoint, NIL_RTUID /* Owner, unchanged */, pOpts->gid, RTPATH_F_ON_LINK); if (RT_SUCCESS(rc)) { rc = RTPathSetMode(pszMountPoint, fMode); if (RT_FAILURE(rc)) { if (rc == VERR_WRITE_PROTECT) { VGSvcVerbose(3, "vbsvcAutoMountPrepareMountPoint: Mount directory '%s' already is used/mounted\n", pszMountPoint); rc = VINF_SUCCESS; } else VGSvcError("vbsvcAutoMountPrepareMountPoint: Could not set mode %RTfmode for mount directory '%s', rc = %Rrc\n", fMode, pszMountPoint, rc); } } else VGSvcError("vbsvcAutoMountPrepareMountPoint: Could not set permissions for mount directory '%s', rc = %Rrc\n", pszMountPoint, rc); } else VGSvcError("vbsvcAutoMountPrepareMountPoint: Could not create mount directory '%s' with mode %RTfmode, rc = %Rrc\n", pszMountPoint, fMode, rc); return rc; } /** * Mounts a shared folder. * * @returns VBox status code reflecting unmount and mount point preparation * results, but not actual mounting * * @param pszShareName The shared folder name. * @param pszMountPoint The mount point. * @param pOpts The mount options. */ static int vbsvcAutoMountSharedFolder(const char *pszShareName, const char *pszMountPoint, struct vbsf_mount_opts *pOpts) { AssertPtr(pOpts); int rc = VINF_SUCCESS; bool fSkip = false; /* Already mounted? */ char szAlreadyMountedTo[RTPATH_MAX]; if (vbsvcAutoMountShareIsMounted(pszShareName, szAlreadyMountedTo, sizeof(szAlreadyMountedTo))) { fSkip = true; /* Do if it not mounted to our desired mount point */ if (RTStrICmp(pszMountPoint, szAlreadyMountedTo)) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Shared folder '%s' already mounted to '%s', unmounting ...\n", pszShareName, szAlreadyMountedTo); rc = vbsvcAutoMountUnmount(szAlreadyMountedTo); if (RT_SUCCESS(rc)) fSkip = false; else VGSvcError("vbsvcAutoMountWorker: Failed to unmount '%s', %s (%d)! (rc=%Rrc)\n", szAlreadyMountedTo, strerror(errno), errno, rc); /** @todo errno isn't reliable at this point */ } if (fSkip) VGSvcVerbose(3, "vbsvcAutoMountWorker: Shared folder '%s' already mounted to '%s', skipping\n", pszShareName, szAlreadyMountedTo); } if (!fSkip && RT_SUCCESS(rc)) rc = vbsvcAutoMountPrepareMountPoint(pszMountPoint, pszShareName, pOpts); if (!fSkip && RT_SUCCESS(rc)) { #ifdef RT_OS_SOLARIS char szOptBuf[MAX_MNTOPT_STR] = { '\0', }; int fFlags = 0; if (pOpts->ronly) fFlags |= MS_RDONLY; RTStrPrintf(szOptBuf, sizeof(szOptBuf), "uid=%d,gid=%d,dmode=%0o,fmode=%0o,dmask=%0o,fmask=%0o", pOpts->uid, pOpts->gid, pOpts->dmode, pOpts->fmode, pOpts->dmask, pOpts->fmask); int r = mount(pszShareName, pszMountPoint, fFlags | MS_OPTIONSTR, "vboxfs", NULL, /* char *dataptr */ 0, /* int datalen */ szOptBuf, sizeof(szOptBuf)); if (r == 0) VGSvcVerbose(0, "vbsvcAutoMountWorker: Shared folder '%s' was mounted to '%s'\n", pszShareName, pszMountPoint); else if (errno != EBUSY) /* Share is already mounted? Then skip error msg. */ VGSvcError("vbsvcAutoMountWorker: Could not mount shared folder '%s' to '%s', error = %s\n", pszShareName, pszMountPoint, strerror(errno)); #elif defined(RT_OS_LINUX) unsigned long fFlags = MS_NODEV; /*const char *szOptions = { "rw" }; - ??? */ struct vbsf_mount_info_new mntinf; mntinf.nullchar = '\0'; mntinf.signature[0] = VBSF_MOUNT_SIGNATURE_BYTE_0; mntinf.signature[1] = VBSF_MOUNT_SIGNATURE_BYTE_1; mntinf.signature[2] = VBSF_MOUNT_SIGNATURE_BYTE_2; mntinf.length = sizeof(mntinf); mntinf.uid = pOpts->uid; mntinf.gid = pOpts->gid; mntinf.ttl = pOpts->ttl; mntinf.dmode = pOpts->dmode; mntinf.fmode = pOpts->fmode; mntinf.dmask = pOpts->dmask; mntinf.fmask = pOpts->fmask; strcpy(mntinf.name, pszShareName); strcpy(mntinf.nls_name, "\0"); int r = mount(pszShareName, pszMountPoint, "vboxsf", fFlags, &mntinf); if (r == 0) { VGSvcVerbose(0, "vbsvcAutoMountWorker: Shared folder '%s' was mounted to '%s'\n", pszShareName, pszMountPoint); r = vbsfmount_complete(pszShareName, pszMountPoint, fFlags, pOpts); switch (r) { case 0: /* Success. */ errno = 0; /* Clear all errors/warnings. */ break; case 1: VGSvcError("vbsvcAutoMountWorker: Could not update mount table (failed to create memstream): %s\n", strerror(errno)); break; case 2: VGSvcError("vbsvcAutoMountWorker: Could not open mount table for update: %s\n", strerror(errno)); break; case 3: /* VGSvcError("vbsvcAutoMountWorker: Could not add an entry to the mount table: %s\n", strerror(errno)); */ errno = 0; break; default: VGSvcError("vbsvcAutoMountWorker: Unknown error while completing mount operation: %d\n", r); break; } } else /* r == -1, we got some error in errno. */ { if (errno == EPROTO) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Messed up share name, re-trying ...\n"); /** @todo r=bird: What on earth is going on here????? Why can't you * strcpy(mntinf.name, pszShareName) to fix it again? */ /* Sometimes the mount utility messes up the share name. Try to * un-mangle it again. */ char szCWD[RTPATH_MAX]; size_t cchCWD; if (!getcwd(szCWD, sizeof(szCWD))) { VGSvcError("vbsvcAutoMountWorker: Failed to get the current working directory\n"); szCWD[0] = '\0'; } cchCWD = strlen(szCWD); if (!strncmp(pszMountPoint, szCWD, cchCWD)) { while (pszMountPoint[cchCWD] == '/') ++cchCWD; /* We checked before that we have enough space */ strcpy(mntinf.name, pszMountPoint + cchCWD); } r = mount(mntinf.name, pszMountPoint, "vboxsf", fFlags, &mntinf); } if (r == -1) /* Was there some error from one of the tries above? */ { switch (errno) { /* If we get EINVAL here, the system already has mounted the Shared Folder to another * mount point. */ case EINVAL: VGSvcVerbose(0, "vbsvcAutoMountWorker: Shared folder '%s' already is mounted!\n", pszShareName); /* Ignore this error! */ break; case EBUSY: /* Ignore these errors! */ break; default: VGSvcError("vbsvcAutoMountWorker: Could not mount shared folder '%s' to '%s': %s (%d)\n", pszShareName, pszMountPoint, strerror(errno), errno); rc = RTErrConvertFromErrno(errno); break; } } } #else # error "PORTME" #endif } VGSvcVerbose(3, "vbsvcAutoMountWorker: Mounting returned with rc=%Rrc\n", rc); return rc; } /** * Processes shared folder mappings retrieved from the host. * * @returns VBox status code. * @param paMappings The mappings. * @param cMappings The number of mappings. * @param pszMountDir The mount directory. * @param pszSharePrefix The share prefix. * @param uClientID The shared folder service (HGCM) client ID. */ static int vbsvcAutoMountProcessMappings(PCVBGLR3SHAREDFOLDERMAPPING paMappings, uint32_t cMappings, const char *pszMountDir, const char *pszSharePrefix, uint32_t uClientID) { if (cMappings == 0) return VINF_SUCCESS; AssertPtrReturn(paMappings, VERR_INVALID_PARAMETER); AssertPtrReturn(pszMountDir, VERR_INVALID_PARAMETER); AssertPtrReturn(pszSharePrefix, VERR_INVALID_PARAMETER); AssertReturn(uClientID > 0, VERR_INVALID_PARAMETER); /** @todo r=bird: Why is this loop schitzoid about status codes? It quits if * RTPathJoin fails (i.e. if the user specifies a very long name), but happily * continues if RTStrAPrintf failes (mem alloc). * * It also happily continues if the 'vboxsf' group is missing, which is a waste * of effort... In fact, retrieving the group ID could probably be done up * front, outside the loop. */ int rc = VINF_SUCCESS; for (uint32_t i = 0; i < cMappings && RT_SUCCESS(rc); i++) { char *pszShareName = NULL; rc = VbglR3SharedFolderGetName(uClientID, paMappings[i].u32Root, &pszShareName); if ( RT_SUCCESS(rc) && *pszShareName) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Connecting share %u (%s) ...\n", i+1, pszShareName); /** @todo r=bird: why do you copy things twice here and waste heap space? * szMountPoint has a fixed size. * @code * char szMountPoint[RTPATH_MAX]; * rc = RTPathJoin(szMountPoint, sizeof(szMountPoint), pszMountDir, *pszSharePrefix ? pszSharePrefix : pszShareName); * if (RT_SUCCESS(rc) && *pszSharePrefix) * rc = RTStrCat(szMountPoint, sizeof(szMountPoint), pszShareName); * @endcode */ char *pszShareNameFull = NULL; if (RTStrAPrintf(&pszShareNameFull, "%s%s", pszSharePrefix, pszShareName) > 0) { char szMountPoint[RTPATH_MAX]; rc = RTPathJoin(szMountPoint, sizeof(szMountPoint), pszMountDir, pszShareNameFull); if (RT_SUCCESS(rc)) { VGSvcVerbose(4, "vbsvcAutoMountWorker: Processing mount point '%s'\n", szMountPoint); struct group *grp_vboxsf = getgrnam("vboxsf"); if (grp_vboxsf) { struct vbsf_mount_opts mount_opts = { 0, /* uid */ (int)grp_vboxsf->gr_gid, /* gid */ 0, /* ttl */ 0770, /* dmode, owner and group "vboxsf" have full access */ 0770, /* fmode, owner and group "vboxsf" have full access */ 0, /* dmask */ 0, /* fmask */ 0, /* ronly */ 0, /* sloppy */ 0, /* noexec */ 0, /* nodev */ 0, /* nosuid */ 0, /* remount */ "\0", /* nls_name */ NULL, /* convertcp */ }; rc = vbsvcAutoMountSharedFolder(pszShareName, szMountPoint, &mount_opts); } else VGSvcError("vbsvcAutoMountWorker: Group 'vboxsf' does not exist\n"); } else VGSvcError("vbsvcAutoMountWorker: Unable to join mount point/prefix/shrae, rc = %Rrc\n", rc); RTStrFree(pszShareNameFull); } else VGSvcError("vbsvcAutoMountWorker: Unable to allocate full share name\n"); RTStrFree(pszShareName); } else VGSvcError("vbsvcAutoMountWorker: Error while getting the shared folder name for root node = %u, rc = %Rrc\n", paMappings[i].u32Root, rc); } /* for cMappings. */ return rc; } /** * @interface_method_impl{VBOXSERVICE,pfnWorker} */ static DECLCALLBACK(int) vbsvcAutoMountWorker(bool volatile *pfShutdown) { /* * Tell the control thread that it can continue * spawning services. */ RTThreadUserSignal(RTThreadSelf()); uint32_t cMappings; PVBGLR3SHAREDFOLDERMAPPING paMappings; int rc = VbglR3SharedFolderGetMappings(g_SharedFoldersSvcClientID, true /* Only process auto-mounted folders */, &paMappings, &cMappings); if ( RT_SUCCESS(rc) && cMappings) { char *pszMountDir; rc = VbglR3SharedFolderGetMountDir(&pszMountDir); if (rc == VERR_NOT_FOUND) rc = RTStrDupEx(&pszMountDir, VBOXSERVICE_AUTOMOUNT_DEFAULT_DIR); if (RT_SUCCESS(rc)) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Shared folder mount dir set to '%s'\n", pszMountDir); char *pszSharePrefix; rc = VbglR3SharedFolderGetMountPrefix(&pszSharePrefix); if (RT_SUCCESS(rc)) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Shared folder mount prefix set to '%s'\n", pszSharePrefix); #ifdef USE_VIRTUAL_SHARES /* Check for a fixed/virtual auto-mount share. */ if (VbglR3SharedFolderExists(g_SharedFoldersSvcClientID, "vbsfAutoMount")) { VGSvcVerbose(3, "vbsvcAutoMountWorker: Host supports auto-mount root\n"); } else { #endif VGSvcVerbose(3, "vbsvcAutoMountWorker: Got %u shared folder mappings\n", cMappings); rc = vbsvcAutoMountProcessMappings(paMappings, cMappings, pszMountDir, pszSharePrefix, g_SharedFoldersSvcClientID); #ifdef USE_VIRTUAL_SHARES } #endif RTStrFree(pszSharePrefix); } /* Mount share prefix. */ else VGSvcError("vbsvcAutoMountWorker: Error while getting the shared folder mount prefix, rc = %Rrc\n", rc); RTStrFree(pszMountDir); } else VGSvcError("vbsvcAutoMountWorker: Error while getting the shared folder directory, rc = %Rrc\n", rc); VbglR3SharedFolderFreeMappings(paMappings); } else if (RT_FAILURE(rc)) VGSvcError("vbsvcAutoMountWorker: Error while getting the shared folder mappings, rc = %Rrc\n", rc); else VGSvcVerbose(3, "vbsvcAutoMountWorker: No shared folder mappings found\n"); /* * Because this thread is a one-timer at the moment we don't want to break/change * the semantics of the main thread's start/stop sub-threads handling. * * This thread exits so fast while doing its own startup in VGSvcStartServices() * that this->fShutdown flag is set to true in VGSvcThread() before we have the * chance to check for a service failure in VGSvcStartServices() to indicate * a VBoxService startup error. * * Therefore *no* service threads are allowed to quit themselves and need to wait * for the pfShutdown flag to be set by the main thread. */ /** @todo r=bird: Shared folders have always been configurable at run time, so * this service must be changed to check for changes and execute those changes! * * The 0.5sec sleep here is just soo crude and must go! */ for (;;) { /* Do we need to shutdown? */ if (*pfShutdown) break; /* Let's sleep for a bit and let others run ... */ RTThreadSleep(500); } VGSvcVerbose(3, "vbsvcAutoMountWorker: Finished with rc=%Rrc\n", rc); return VINF_SUCCESS; } /** * @interface_method_impl{VBOXSERVICE,pfnTerm} */ static DECLCALLBACK(void) vbsvcAutoMountTerm(void) { VGSvcVerbose(3, "vbsvcAutoMountTerm\n"); VbglR3SharedFolderDisconnect(g_SharedFoldersSvcClientID); g_SharedFoldersSvcClientID = 0; if (g_AutoMountEvent != NIL_RTSEMEVENTMULTI) { RTSemEventMultiDestroy(g_AutoMountEvent); g_AutoMountEvent = NIL_RTSEMEVENTMULTI; } return; } /** * @interface_method_impl{VBOXSERVICE,pfnStop} */ static DECLCALLBACK(void) vbsvcAutoMountStop(void) { RTSemEventMultiSignal(g_AutoMountEvent); } /** * The 'automount' service description. */ VBOXSERVICE g_AutoMount = { /* pszName. */ "automount", /* pszDescription. */ "Auto-mount for Shared Folders", /* pszUsage. */ NULL, /* pszOptions. */ NULL, /* methods */ VGSvcDefaultPreInit, VGSvcDefaultOption, vbsvcAutoMountInit, vbsvcAutoMountWorker, vbsvcAutoMountStop, vbsvcAutoMountTerm };