This is an automated email from the git hooks/post-receive script. x2go pushed a commit to branch master in repository x2goclient. commit f22fd1957a8b16a80588451cc3e0dab26c2d5c8b Author: Mihai Moldovan <ionic@ionic.de> Date: Thu Jun 14 04:11:15 2018 +0200 src/onmainwindow.cpp: hook-in chgrp for ~/.x2go/etc on Windows platforms to work around a Cygwin permissions bug. Fixes: #1156. --- debian/changelog | 2 + src/onmainwindow.cpp | 117 +++++++++++++++++++++++++++++++++++++++++++++++++++ src/onmainwindow.h | 1 + 3 files changed, 120 insertions(+) diff --git a/debian/changelog b/debian/changelog index da8f2c1..fe06805 100644 --- a/debian/changelog +++ b/debian/changelog @@ -86,6 +86,8 @@ x2goclient (4.1.2.0-0x2go1) UNRELEASED; urgency=medium Server startup functions. - src/pulsemanager.cpp: use QByteArray's constData () instead of data (), since we'll never modify the data anyway. + - src/onmainwindow.cpp: hook-in chgrp for ~/.x2go/etc on Windows platforms + to work around a Cygwin permissions bug. Fixes: #1156. * x2goclient.spec: - Remove plugin references. * debian/rules: diff --git a/src/onmainwindow.cpp b/src/onmainwindow.cpp index fa39cd8..712bd4c 100644 --- a/src/onmainwindow.cpp +++ b/src/onmainwindow.cpp @@ -10397,6 +10397,118 @@ void ONMainWindow::slotSetWinServersReady() restoreCygnusSettings(); } +void ONMainWindow::workaround_cygwin_permissions_issue () { + /* + * Traditionally, user home directories were owned by a group called "None" + * (or usually also translated into the system locale, because it's + * Windows...). + * + * Newer versions, at least Windows 10 and higher, set the group to the + * user's group, quite like on Linux. + * + * This has interesting consequences for older Cygwin versions (up to + * 1.7.34 probably - we currently use 1.7.33). + * Windows has a general concept of users and groups, but keeps a database + * of both in a combined way, with actually unique IDs. Hence, if a + * directory is owned by an ID that corresponds to the user both in the + * owner and group ACLs, then Cygwin gets confused with owner and group + * permissions. + * Even though the effective group permissions might be "---", it somehow + * manages to map the effective owner permissions, that typically are + * "rwx", to the UNIX group permissions as well. + * Consequently, OpenSSH will error out complaining about the permissions + * of the host keys being too open, even though they really are not. + * + * To work around this problem, we will reset the group ID of + * ~/.x2go/etc to the None group ID, which conveniently has a reserved and + * fixed value of 513 (RID) or 197121 (Cygwin) across all systems. + * + * Note that we don't have to do that for ~/x2go/ssh/gen, since we disable + * file permission checks for user keys. + */ + QString etc_dir = cygwinPath (wapiShortFileName (homeDir + "/.x2go/etc")); + + QStringList args; + args << "-R" << "-v" << etc_dir; + + QProcess chgrp; + chgrp.setStandardInputFile (nullDevice ()); + chgrp.start ("chgrp", args); + + bool fail = false; + while (!(chgrp.waitForStarted (10))) { + /* + * If the process state is still "Starting", it means that the timer in + * waitForStarted () ran out. Continue normal execution, otherwise + * handle the startup error. + */ + if (QProcess::Starting != chgrp.state ()) { + fail = true; + + break; + } + + QCoreApplication::processEvents (QEventLoop::AllEvents, 10); + } + + if (fail) { + show_RichText_WarningMsgBox (tr ("Unable to start chgrp helper."), + tr ("Changing the group permissions of the X2Go Client-specific " + "OpenSSH server configuration will not take place.") + + "\n" + + tr ("The OpenSSH server might fail to start on newer Windows " + "versions (10 and higher)."), + false); + + x2goDebug << "Failed to start chgrp: " << chgrp.error () + << " with exit status " << chgrp.exitStatus () + << " and exit code " << chgrp.exitCode () + << " (invalid unless exit status was QProcess::NormalExit)" + << "; continuing without directory regrouping. sshd might " + << "fail to start up."; + + return; + } + + fail = false; + while (!(chgrp.waitForFinished (10))) { + /* + * Pretty much the same logic as above, only slightly adaptated: + * a timeout only makes sense if the process is still "Running". + * Otherwise it must have died. + */ + if (QProcess::Running != chgrp.state ()) { + fail = true; + + break; + } + + QCoreApplication::processEvents (QEventLoop::AllEvents, 10); + } + + fail = ((fail) || (QProcess::NormalExit != chgrp.exitStatus ())); + + if (fail) { + show_RichText_WarningMsgBox (tr ("Execution failure of chgrp helper."), + tr ("Changing the group permissions of the X2Go Client-specific " + "OpenSSH server configuration will not take place.") + + "\n" + + tr ("The OpenSSH server might fail to start on newer Windows " + "versions (10 and higher)."), + false); + + x2goDebug << "chgrp failed during execution: " << chgrp.error () + << " with exit status " << chgrp.exitStatus () + << " and exit code " << chgrp.exitCode () + << " (invalid unless exit status was QProcess::NormalExit)" + << "; continuing without directory regrouping. sshd might " + << "fail to start up."; + } + + x2goDebug << "chgrp stdout: " << chgrp.readAllStandardOutput () + << endl << "chgrp stderr: " << chgrp.readAllStandardError (); +} + #include <windows.h> #include<sstream> #endif @@ -10822,8 +10934,13 @@ bool ONMainWindow::startSshd(ONMainWindow::key_types key_type) */ generateEtcFiles (); +#ifdef Q_OS_WIN + workaround_cygwin_permissions_issue (); +#endif + clientSshPort = "7022"; QString etcDir=homeDir+"/.x2go/etc"; + int port=clientSshPort.toInt(); //clientSshPort have initvalue while ( isServerRunning ( port ) ) diff --git a/src/onmainwindow.h b/src/onmainwindow.h index 47eaa5e..2b78261 100644 --- a/src/onmainwindow.h +++ b/src/onmainwindow.h @@ -1187,6 +1187,7 @@ private: #ifdef Q_OS_WIN void saveCygnusSettings(); void restoreCygnusSettings(); + void workaround_cygwin_permissions_issue (); #endif #if defined (Q_OS_WIN) || defined (Q_OS_DARWIN) QString getXDisplay(); -- Alioth's /home/x2go-admin/maintenancescripts/git/hooks/post-receive-email on /srv/git/code.x2go.org/x2goclient.git