Intrepid regression: carriage-return required after finger scan

I confirm

Thanks for the response. I've recently had occasion to do a full install of 8.04 followed by the installation of thinkfinger and this bug has not appeared, atm I can not repeat it.

confirming this recently began happening on my intrepid install.

I can confirm this on Intrepid as well.

It seems to be related to libpam-thinkfinger's use of uinput. libpam-thinkfinger creates a uinput device to send a EV_KEY/KEY_ENTER press and release. This event _should_ emulate the enter key being pressed after a finger swipe so that the user does not have to press it manually.

I don't see any errors in the pam debug output about sending the enter event. Either libpam-thinkfinger is misusing uinput somehow or GDM is not processing the key event (maybe it's blocking focus on the password prompt textbox?).

Regards,
Jon Oberheide

After debugging for far too many hours, I have an apparent hack/fix.

Simply setting another KEYBIT along with our KEY_ENTER seems to fix the issue. The other KEYBIT can be any value and it doesn't seem to matter if the other KEYBIT is set before or after KEY_ENTER. If another KEYBIT is not set, it appears that the kernel is not sending the KEY_ENTER event.

I don't recommend committing this until we figure out what the root cause is, but if anyone else experiencing the problem could test it and verify that it resolves their issue, that'd be great.h

FYI, this issue of not receiving a key event when only one is set is reproducible in a standalone test program outside of thinkfinger-pam. So either it's a kernel issue or for some reason uinput wasn't designed to work with only a single KEYBIT set (which seems incorrect since it worked with earlier kernels).

I also notify that the bug doesn't happen when you are in a virtual terminal (ctrl-alt-f1) .

Ah, nice catch Patrick. Perhaps it is something in xorg/xinput/xorg-input-evdev. I'll try to bisect.

I can confirm that downgrading all my xorg packages to hardy fixes the problem.

I also can confirm this issue. The problem does not happen on the console (ctrl-alt-f1), but in X.
I had no problems before upgrading to Intrepid.

I've attached two samples that show this behavior outside of thinkfinger.

They both create a uinput device and send a KEY_ENTER event. In bad.c, when the device is only set up with a KEY_ENTER key, the KEY_ENTER event is not observed in X. However, in good.c, if another supported key (say KEY_A) is added to the uinput device as well, the sending of the KEY_ENTER event works just fine.

Both of the testcases work as expected outside of X in the terminal which leads to me to believe something is getting munged in X's input layer.

My guess is that the new input hotplugging magic selects the wrong driver for the uinput device.

If I add a section (this might already be there, not sure anymore)

Section "InputDevice"
        Identifier "Generic Keyboard"
        Driver "kbd"
        Option "XkbRules" "xorg"
        Option "XkbModel" "pc105"
        Option "XkbLayout" "us"
EndSection

to my xorg.conf and then enable it by adding a line

        InputDevice "Generic Keyboard"

to the "ServerLayout" section, the fingerprint reader works as before.

That works great for me.
The InputDevice section was already there with the entry for the keyboard. But I had to add the line to the "ServerLayout" section. Once I restarted X, I could log in without following the swipe with a carriage return.

Attached is a patch to thinkfinger that should workaround the bug by adding a dummy key (KEY_A) to the uinput device.

It's certainly not a proper fix to why xorg is not correctly sending the KEY_ENTER but it's certainly an option for those of you who find hitting enter after you swipe annoying and/or don't have an xorg.conf to add the configuration workaround.

Tom's workaround worked for me. The keyboard input device and serverlayout reference were commented out claiming that HAL would deal with them after the upgrade. I uncommented and all works as before.

I don't see a "ServerLayout" section" on Intrepid Ibex using Envy to handle my xorg.conf.

Perhaps this should be reported upstream at freedesktop's bug tracker?

<quote>
to my xorg.conf and then enable it by adding a line

        InputDevice "Generic Keyboard"

to the "ServerLayout" section, the fingerprint reader works as before.
</quote>

Adding this to my xorg.conf causes unwanted side-effects, such as causing my volume control button next to my headphone jack to stop working, and bizarrely stopping the key combinations ctrl-<arrow key> to stop working also. So this is not an option for me.

Packages which resolve this issue are available in my PPA:

https://launchpad.net/~jon-oberheide/+archive

deb http://ppa.launchpad.net/jon-oberheide/ubuntu intrepid main
deb-src http://ppa.launchpad.net/jon-oberheide/ubuntu intrepid main

You are the man Jon Oberheide!!
Everything work just fine now.

will the fix be included in the main archive?

Unsure. It uses the workaround patch previously posted (adding a dummy KEY_A key capability to the uinput device). Without the workaround, the uinput device doesn't even show up in "xinput list". For some reason, a keyboard uinput device with only a KEY_ENTER is not sufficient to be registered.

So while it's more of a workaround than a fix, it does indeed resolve the issue and has absolutely zero side effects.

FWIW, neither Fedora 9 nor Fedora 10 (probably the more relevant of the two) exhibits the problem.

I had the same problem. I installed the packages from Jon Oberheide's PPA and it worked. Thanks Jon.

Here's the lsusb output for my fingerprint reader:

Bus 001 Device 004: ID 0483:2016 SGS Thomson Microelectronics Fingerprint Reader

I'm on a Thinkpad X61.

I've tracked down the source of this issue in hal's hald/linux/device.c. When a new input device is added, it goes through a series of checks to determine what kind of device it is (mouse, keyboard, etc).

In input_test_key(), hal will figure out the size of the bitmask of the devices (num_bits, aka the number of "buttons" this input device has). If num_bits == 1, hal will treat the device as a "button" (eg. power/sleep/hibernate button) rather than a keyboard. Otherwise, it will run further checks to see what kind of keyboard it is (input_test_keyboard(), input_test_keypad()).

This explains exactly why having only a single key on the uinput device (KEY_ENTER) fails to work and adding a second dummy key (KEY_A) fixes the problem. Without the dummy key, the uinput device is treated as a "button" instead of a "keyboard" and does not send the KEY_ENTER event when using libpam-thinkfinger.

I'll email upstream and figure out if there's a proper fix to allow one-button keyboards or if hacking around it is the best approach.

Recently upgraded from ubuntu 8.04 to 8.10 on my Dell XPS 1330, the finger print module worked perfectly before the upgrade, but now .....
firstly I had to hit carriage return after the swipe, but this was later fixed after I installed packages from Jon Oberheide.
But there's something else I realized now, if I try to type my password (instead of swiping my finger) then it prompts me to retype the password, and it does this thrice.

sachem_s: please file a separate bug for your inability to log in by typing the password instead of swiping a finger.

sachem_s: please check if in /etc/pam.d/common-auth you have the "try_first_pass" option to the pam_unix.so module, something like this:

auth [success=1 default=ignore] pam_unix.so try_first_pass nullok_secure

otherwise that module won't use the password previously submitted to the thinkfinger module, and it will prompt you for another password.

Thx Jon Oberheide, this works great! Also nice bug tracking and description.

I added this fix to the thinkwiki descriptions for T61p (see: http://www.thinkwiki.org/wiki/Install_Ubuntu_Intrepid_Ibex_on_a_T61p#Fingerprint_Reader)

Jon: I've libpam-thinkfinger 0.3+r118-0ubuntu4~ppa1 from your PPA. It has the following problem: if you type in your password and press Enter at the 'Password or swipe finger:' prompt, it still sends that extra Enter keypress (twice!). So, for example, if you do sudo apt-get dist-upgrade, you get no choice to answer the first two apt's confirmation prompts -- they get answered for you.

If I swipe my finger, no spurious Enter keystrokes appear.

This regression still exists in Jaunty, too.

Marius: The extra "Enter" keypress that you describe may not be due to the modified package 0.3+r118-0ubuntu4~ppa1. See Bug #236344 in thinkfinger which seems (?) to describe the same problem with the unmodified package.

Thanks Jon Oberheide!
Your patch works perfectly for me.
The modifying of the xorg.conf did break my keyboard layout (keyup got interpreted as print key...)

I suspect, but have yet to test, that the extra <CR> defect was introduced in revision 116 of the upstream code:

  http://thinkfinger.svn.sourceforge.net/viewvc/thinkfinger/pam/pam_thinkfinger.c?r1=115&r2=116

With Jon's fix in place, I suspect that we can revert that change.

I have confirmed on my system by building Jon's PPA package from source that with Jon's PPA + reverting r116, I have fingerprint working properly and if I choose to type the password, I don't get the extra <cr>.

Jon, do you want to do that in your PPA for people to test? And let's start to get this pushed into Intrepid and Jaunty to fix the bug.

The thinkfinger packages in my PPA are only a workaround for the underlying bug in hal. The upstream hal bug hasn't gotten much attention though.

> The thinkfinger packages in my PPA are only a workaround for the underlying bug in hal.
> The upstream hal bug hasn't gotten much attention though.

Yes, I know. But in the meantime, while waiting for upstream to fix their issues, between your workaround and reverting that change I found, we can have a functioning package that delivers the expected behavior. I say let's go with it. The fixes are simple and maintainable.

FWIW, _how_ we fix the bug will be transparent to the end user but not being able to use their fingerprint scanners is _VERY_ visible. It makes Ubuntu look bad, no matter where the actual fault lies for the problem. If it really is a simple workaround, my preference would be to document that and go with it until upstream gets around to fixing the hal bug. Just my two cents...

Jon, I have attached the patch to Bug 236344. I've tested this with both Intrepid and Jaunty, and we should be good to go with it. Would you mind doing the honors? :-) Do we somehow to have get the attention of Scott James Remnant (q.v., https://launchpad.net/ubuntu/+source/thinkfinger)?

Quick link: http://launchpadlibrarian.net/20621528/pam_thinkfinger-revert-r116-extra-cr.patch

thinkfinger-0.3+r118-0ubuntu4~ppa2 with the r116 revert patch is building now in my PPA. Feel free to give it a test once it lands!

They are up at https://launchpad.net/~jon-oberheide/+archive, so people should please test. And this should also go onto Jaunty.

I installed from your PPA, and it is working fine for me, Jon. I think that we've got this fixed. :-)

What do we need to do to get this into Jaunty and either a backport or update for Intrepid? I suppose for Intrepid the first step would be -proposed.

Not sure why this isn't Confirmed, so I'll do so, as I can confirm it as well. Also thanks Jon, your PPA addressed the issue perfectly for me! I'd love to see this working out-of-the box on Jaunty.

For those of us testing Jaunty, please see Bug 311732. And please confirm if you also see that problem.

Jon,

I have subscribed Scott James Remnant, hoping that he can help us get this patch into MOTU, since he has been doing the thinkfinger packaging most recently.

According to what I understand from https://wiki.ubuntu.com/MOTU/Sponsorship/SponsorsQueue, could you please provide an attached debdiff from the original package to ours? Once we have that, I believe that the process is to subscribe ubuntu-universe-sponsors to the bug.

Here's the composite patch of the key bit workaround and reverting r116.

Jon Oberheide's fix at https://launchpad.net/~jon-oberheide/+archive works great!

After installing Jon Oberheide's packages i can't login to Gnome. After i swipe finger Gnome began to load and immediately crash then GDM reloading. If i enter my password by typing everything fine.
What information should i post here?

Which version of Ubuntu? Is everything else updated? I'm not having any problems except with Jaunty's 2.6.28-4 kernel, which has numerous issues. I use the new packages with Intrepid and with Jaunty's 2.6.28-3 kernel.

Intrepid updated from 8.04.1
Dell xps m1330
2.6.27-11-generic

Output in syslog:

kernel: [ 8496.036565] input: Virtual ThinkFinger Keyboard as /devices/virtual/inpu
t/input14
gdm[10886]: WARNING: gdm_slave_xioerror_handler: Fatal error X - Reloading :0

In Xorg.0.log.old

Backtrace:
0: /usr/X11R6/bin/X(xf86SigHandler+0x79) [0x80c3009]
1: [0xb8020400]
2: /usr/X11R6/bin/X(XkbWriteXKBGeometry+0x181) [0x81a9ed1]
3: /usr/X11R6/bin/X(XkbWriteXKBKeymapForNames+0x610) [0x81a9210]
4: /usr/X11R6/bin/X(XkbDDXLoadKeymapByNames+0x1d7) [0x81b41c7]
5: /usr/X11R6/bin/X(ProcXkbGetKbdByName+0x40e) [0x819041e]
6: /usr/X11R6/bin/X [0x8195668]
7: /usr/X11R6/bin/X(Dispatch+0x34f) [0x808c89f]
8: /usr/X11R6/bin/X(main+0x47d) [0x8071d1d]
9: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe5) [0xb7c1e685]
10: /usr/X11R6/bin/X [0x8071101]
Saw signal 11. Server aborting.

I've the same problem with Jaunty and kernel 2.6.28-11-generic.
The xorg.conf workaround worked for me on intrepid, but it does not work anymore.
I do not suffer for bug #311732, the fingerprint works, but I need to press the enter key.
Are the Jon packages available for Jaunty? Thanks.

Vreixo,

I'll post some thinkfinger packages for Jaunty later today in my PPA.

Regards,
Jon Oberheide

Thanks Jon--having the same issue.

The thinkfinger packages for jaunty are built and available in my PPA:

deb http://ppa.launchpad.net/jon-oberheide/ppa/ubuntu jaunty main
deb-src http://ppa.launchpad.net/jon-oberheide/ppa/ubuntu jaunty main

Let me know if there's any issues!

Regards,
Jon Oberheide

Thank you!

I will test them today evening.

Cheers,
Vreixo

Guys, as noted above, please see Bug 311732. This has been fixed in a PPA (https://launchpad.net/~thjaeger/+archive/ppa) for Jaunty, and is scheduled for jaunty-updates.

They work very well.
Thank you!

Works great for me too. Thanks!

Dear Jon,
I am new to linux.
can you explain me how to install your packages?

thanks

farchumbre, you can follow the instructions here:

https://help.launchpad.net/Packaging/PPA#Installing%20software%20from%20a%20PPA

thanks
now it works great, but there are two problems:
I am using multi keyboards english and french
and as soon as I use the thinkfinger for the first time the keyboards stop working correctly
the other thing is that i can't use thinkfinger to unlock the screen after the screensaver was activated

any ideas?

This bug was fixed in the package thinkfinger - 0.3+r118-0ubuntu4

---------------
thinkfinger (0.3+r118-0ubuntu4) karmic; urgency=low

  [ Thomas Jaeger ]
  * Fix breakage when running on 2.6.28 kernel (LP: #311732)
  * Fix typo in README.Debian (LP: #243339)

  [ Jon Oberheide ]
  * Use a workaround to convince HAL to treat virtual thinkfinger device as a
    keyboard (LP: #256429)
  * Revert r116 to avoid extra CR being sent.

 -- Thomas Jaeger <email address hidden> Mon, 23 Mar 2009 21:20:01 -0400

This behavior has reappeared in karmic sometime over the last couple of days.

@rupa, not for me. What behavior are you seeing, and which version do you have installed?

some more updates and reboots, and things are back to normal. Sorry for the noise.

I have the same problem in karmic before update my system with xorg-edgers PPA packages. I try the Jon Oberheide packages " thinkfinger - 0.3+r118-0ubuntu5~ppa1" , that I understood has the workarround, but without results. I have a 64bit laptop (lenov x61s) with karmic x64

I am working on a fresh 64-bit Karmic install being upgraded from beta onwards. The problem of carriage return being required after finger swipe has appeared over last couple of days - first time I am seeing it in karmic. My version of thinkfinger-tools is 0.3+r118-0ubuntu4. Anyone else seeing this ? and anything else I can do?

No problem for me, it works out-of-the-box in a fresh 64bit karmic install. Note that I have not updated from beta, I have installed the final release.

A reboot seems to have fixed the problem. Seems to have been a situation something like rupa. It appeared for some time, and seems to have got fixed with some updates.

this seems to have come back in lucid...

Confirmed issue is back again on Lucid alpha3. Using package thinkfinger-tools 0.3+r118-0ubuntu4 on 64-bit Lucid alpha3 on Lenovo T61p.

Confirmed issue is back again on Ubuntu 9.10, thinkfinger 0.3+r118-0ubuntu4 on 32-bit, in graphics mode.
In console(CTRL+ALT+F1), work without problem login and sudo.

KERNEL=2.6.31-20-generic
GNOME=2.28.1

I'm not sure to which bug report it was posted, but Ubuntu has decided to no longer support Thinkfinger. fprint is the supported direction, despite its flaws, because no one has been working on Thinkfinger upstream and RedHat is funding fprint development.

Checking the bug reports for the various fprint packages not much seems to be happening in Ubuntu and thinkfinger seems still to be the better option in most cases where the fingerprint reader is supported by thinkfinger.

I'm having the same problem on Lucid, in graphics mode. It works ok in console.

I'm also seeing this in Lucid. Everything seems to work, except I need to hit enter. This had been fixed in 9.10!

I have switched to fprint (Noel, thanks for the hint), it works pretty well on my DELL Vostro 1710, fingerprint is (from lsusb):

 0483:2016 SGS Thomson Microelectronics Fingerprint Reader

I have followed the instructions here: http://reactivated.net/fprint/wiki/Pam_fprint. Configuration is much like thinkfinger.

Once configured, it prompts you to scan your finger, no chance for entering password instead... After several failed attempts, however, it falls back to password authentication. I wonder if there is any way to change such behavior.

Update: I found an app fprint does not work pretty well with: gksu (see bug #347778),

This patch seems to fix the problem in Lucid :
http://sourceforge.net/tracker/?func=detail&atid=889697&aid=2921928&group_id=179573

I built the package with this patch and installed it.
Now I can use sudo in a gnome terminal without hitting the enter key.

Looks like this bug is back in 10.04. Exact same symptoms.

I tried adding Jon's PPA, but there's no packages for Lucid.

Anyone got any ideas? I'm not really keen on the X hack, although I'm more comfortable with it than the patch Samuel Piau wrote about, primarily because I understand what the X hack is doing, not what his pam patch is doing.

The patch linked to in comment #83 works for me.

I'm trying to build a version for my PPA... but I just need to wait for various build messes to complete... I tried doing something useful with the package versions...

Here is a more detailed explanation about this patch, it is not related to pam, but to device input event processing.

At some point xf86-input-evdev was changed to a newer version (2.2.5 to 2.3.1 ?), and they changed the events processing :

    evdev: Only send the events at synchronization time.

    Instead of just posting the button/key press/release events to the
    server as soon as they arrive, add them to an internal queue and post
    them once we receive an EV_SYN synchronization event.

    The motion events are always sent first, followed by the queued events.
    There will be one motion event and possibly many queued button/key
    events posted every EV_SYN event.
    [...]

What happens is the additional key code that was added in previous thinkfinger patch is not sent until a real keystroke happens (when you press enter). The patch here adds a synchronisation event after the key code, so that it is immediately posted.

See the comments from Jon Oberheide and Philipp Gortan (mephinet) in this Gentoo Bug report :
http://bugs.gentoo.org/show_bug.cgi?id=298459

I'm not at a level where I feel comfortable creating my own packages from source, which looks like something you did here. My previous attempts have failed spectacularly.

Are you in a position to share the package you built?

So is the patch works, what's the next step to get it accepted? It would be nice if this regression didn't happen in future distribution updates.

Packages containing the patch are in my PPA at:

  https://launchpad.net/~martin-meltin/+archive/ppa

A quick test seems to show that these packages fix the problem. If others can install, test and confirm then perhaps someone will build an official package for lucid....

Thanks Martin. The packages work.
For some reason they wouldn't install using APT, so I downloaded them and used dpkg to install them.

APT always came back and told me I had the latest version.

I suspect it's because I used to have Jon's PPA and his version number is higher than yours, but that's just a theory.

Good to hear that it works for you too, Nate.

Yeah, the documentation has changed its recommendation for modifying package versions for PPAs, so I followed the new recommendation. Older packagers from PPAs (such as Jon's will probably look newer). You should be able to install mine by doing something like:

  apt-get install libpam-thinkfinger=0.3+r118-0ubuntu4ppamartinmeltin5 \
    libthinkfinger0=0.3+r118-0ubuntu4ppamartinmeltin5 \
    thinkfinger-tools=0.3+r118-0ubuntu4ppamartinmeltin5

After that, if you remove the other PPA from your /etc/apt/sources.list.d/ (or wherever), future updates should work.

I confirm that Martin's version works on my Thinkpad Z61m (SGS Thomson Microelectronics Fingerprint Reader) with Lucid.

The packages from Joe's repo, however, gave me
 Warning: usb_bulk_read expected to read 0x40 (read 0x8 bytes).
when running "tf-tool --acquire" so that I couldn't use ThinkFinger at all.

ThinkFinger packages from Martin's repo work great, everything works as good as in Karmic and Jaunty.

I am confirming: Martin's version works fine here too.
(Got a SGS Thomson Microelectronics Fingerprint Reader).
Thanks!

Since we already have a working fix for thinkfinger why would nobody add it to the official repo? For example for business users working fingerprint authentication may be an important criterion to use or not to use Ubuntu and since thinkfinger did work in Hardy, Jaunty and Karmic, for a lot of people doing dist-upgrade to Lucid this bug might become a really bad surprise!

This is still not fixed in Maverick. Is there any maintainer for this package?

Ubuntu review team, please fast-forward this bug into archive =)

Before this bug will go into archive it should at least be f.i.x.e.d. I've even posted a message to the Ubuntu-motu maillist (http://tinyurl.com/358m7lq) since MOTU is listed as the official package maintainer and ... nothing as you see! Is it really that difficult to add a working patch to a package in the repository? So much for filling bugs and helping developers :(

fix please?

pretty PLEASE?

this really was a nasty surprise when I upgrded from Karmic.

Any word on when this is getting added to the repos? Someone, anyone?

Hi,

For your information, thinkfinger has been removed from Debian almost one year ago because it was dead upstream (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=546005).

I'll upload the fix, but except if someone adopt it, this kind of problems will appear from time to time, with sometime no solutions. My advice is that you upgrade to fprint, as indicated in the Debian bug I referenced.

Fabrice

This bug was fixed in the package thinkfinger - 0.3+r118-0ubuntu5

---------------
thinkfinger (0.3+r118-0ubuntu5) maverick; urgency=low

  * pam/pam_thinkfinger-uinput.c: Send sync events to ensure key events are
    processed (LP: #256429). Patch taken from upstream bug tracker
    (http://sourceforge.net/tracker/?func=detail&atid=889697&aid=2921928&group_id=179573)
 -- Thomas Jaeger <email address hidden> Sat, 24 Jul 2010 10:19:07 +0200

Thanks for uploading the package. fprint is just as dead upstream as
thinkfinger, and in addition does not allow the user to chose between
fingerprint and password authentication, so it's not a viable
alternative at this point.

On 07/27/2010 05:53 AM, Fabrice Coutadeur wrote:
> Hi,
>
> For your information, thinkfinger has been removed from Debian almost
> one year ago because it was dead upstream (http://bugs.debian.org/cgi-
> bin/bugreport.cgi?bug=546005).
>
> I'll upload the fix, but except if someone adopt it, this kind of
> problems will appear from time to time, with sometime no solutions. My
> advice is that you upgrade to fprint, as indicated in the Debian bug I
> referenced.
>
> Fabrice
>
> ** Bug watch added: Debian Bug tracker #546005
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=546005
>

If anyone is using thinkfinger with Maverick, please see Bug 609645. As noted there, I'm seeing the failure with the newly uploaded thinkfinger as well as current versions of fprint(d).

Excuse me, but why did you add it only to Maverick repos? What about Lucid?

Indeed, are there any plans to fix in Lucid?

I took the suggestion and upgraded to fprint for a couple of months. It is a downgrade. pam_thinkfinger at least prompts sensibly when doing the gsudo-type things. pam_fprint just sits there stupidly and you have to guess when something is waiting for a fingerprint scan or password. Combine that with not being able to type the password while a scan is being requested and you have a pretty frustrating piece of software... :-(