Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
Control: tags -1 + fixed-upstream This issue has been addressed by upstream in [1], and is included in version 2.0.9. It would be nice if that version could be packaged. -- Håvard [1] https://github.com/Xubuntu/lightdm-gtk-greeter/pull/80
Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
Package: lightdm-gtk-greeter Version: 2.0.1-2 Followup-For: Bug #785237 Dear Maintainer, for what it is worth, i fully support this feature-request (as i was to create a new one due the to very same problems that andreas was/is facing). mfgadsr IOhannes -- System Information: Debian Release: stretch/sid APT prefers unstable APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.6.0-1-amd64 (SMP w/4 CPU cores) Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages lightdm-gtk-greeter depends on: ii libc6 2.23-4 ii libcairo2 1.14.6-1+b1 ii libgdk-pixbuf2.0-0 2.34.0-1 ii libglib2.0-02.48.1-2 ii libgtk-3-0 3.20.6-2 ii liblightdm-gobject-1-0 1.18.2-2 ii libx11-62:1.6.3-1 Versions of packages lightdm-gtk-greeter recommends: ii desktop-base 8.0.2 ii gnome-icon-theme-symbolic 3.12.0-2 ii gnome-themes-standard 3.20.2-3 ii policykit-10.105-16 lightdm-gtk-greeter suggests no packages. -- no debconf information
Bug#785237: [Pkg-xfce-devel] Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
Hi Maintainer, I'm wondering if you have been able to further consider this possibility. I have made a patch for version 1.8.5-2 which strips spaces from the username, and it has been successfully deployed without issues at the Open Computing Facility. The patch itself is only a few lines long, affecting the function "username_focus_out_cb". I would be happy to provide it if desired. As Andreas has previously noted, on Debian a username with a space cannot be created, barring manual editing of the username database. In particular, I have yet to see a single real example of a username starting with leading spaces, especially not one which would be used to log in to a graphical environment. Hence, there should be no realistic adverse impact by applying such a change. Best, Kevin
Bug#785237: [Pkg-xfce-devel] Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
On 05/13/2015 10:52:49 PM, Yves-Alexis Perez wrote:
On mer., 2015-05-13 at 20:05 +0200, Andreas Schmidt wrote:
Package: lightdm-gtk-greeter
Version: 2.0.0-3
Severity: wishlist
Wouldn't it be possible to remove leading spaces from the input in
the user
name field before matching user and password? Are leading spaces in
user names
even allowed? If so, unconditionally removing them could cause
issues for
people
with such user names. These might be prevented, however, if the
test was for a
match of (password and username) OR (password and username without
leading
spaces), rather than just (password and username).
I'm honestly really not confident about that, that doesn't look like a
great idea at first sight, so you'd have to justify a bit more it's
safe.
root@debian:~# adduser ' test'
adduser: To avoid problems, the username should consist only of
letters, digits, underscores, periods, at signs and dashes, and not
start with
a dash (as defined by IEEE Std 1003.1-2001). For compatibility with
Samba
machine accounts $ is also supported at the end of the username
root@debian:~#
root@debian:~# useradd ' test'
useradd: invalid user name ' test'
root@debian:~# man useradd
[...]
CAVEATS
[...]
It is usually recommended to only use usernames that begin with
a lower case letter or an underscore, followed by lower case letters,
digits, underscores, or dashes. They can
end with a dollar sign. In regular expression terms:
[a-z_][a-z0-9_-]*[$]?
On Debian, the only constraints are that usernames must neither
start with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a
colon (':'), a comma (','), or a whitespace
(space: ' ', end of line: '\n', tabulation: '\t', etc.). Note
that using a slash ('/') may break the default algorithm for the
definition of the user's home directory.
[...]
At least on Debian, it seems to be impossible to have usernames
starting with white space. I don't know about other distros, or
filesystems on different systems that are mounted into Debian. Also,
I'm not much of a programmer, so I really don't know whether there
would be implications beyond user cannot login (which would be
serious enough). But from my naive perspective, it seems that removing
stuff which shouldn't be there in the first place should be OK.
However, if removing leading spaces seems too radical, I would also be
happy about getting a visual warning -- similar to the hint Caps Lock
is on in the password field. The problem is that a single space in
front of the user name is too hard to see, as it is not really wide
enough. To know exactly why a login attempt failed (wrong user name
instead of wrong password) would be far less frustrating than poking
around in the dark.
Best regards,
Andreas
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Bug#785237: [Pkg-xfce-devel] Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
On mer., 2015-05-13 at 20:05 +0200, Andreas Schmidt wrote: Package: lightdm-gtk-greeter Version: 2.0.0-3 Severity: wishlist Dear Maintainer, I work at a laptop computer that I usually suspend instead of shutting down. After opening the lid, I usually tap the space key to restart the computer. Sometimes, a spurious space character makes it into the field for the user name as first character. Naturally, user name and password don't match in this case. However, as my password is quite long, I usually tend to assume I have mistyped the password, thus losing time and nerves by repeatedly retyping the password before thinking of the stray space character in front of the user name. :-) Wouldn't it be possible to remove leading spaces from the input in the user name field before matching user and password? Are leading spaces in user names even allowed? If so, unconditionally removing them could cause issues for people with such user names. These might be prevented, however, if the test was for a match of (password and username) OR (password and username without leading spaces), rather than just (password and username). I'm honestly really not confident about that, that doesn't look like a great idea at first sight, so you'd have to justify a bit more it's safe. Regards, -- Yves-Alexis signature.asc Description: This is a digitally signed message part
Bug#785237: lightdm-gtk-greeter: Please remove leading spaces from user name
Package: lightdm-gtk-greeter Version: 2.0.0-3 Severity: wishlist Dear Maintainer, I work at a laptop computer that I usually suspend instead of shutting down. After opening the lid, I usually tap the space key to restart the computer. Sometimes, a spurious space character makes it into the field for the user name as first character. Naturally, user name and password don't match in this case. However, as my password is quite long, I usually tend to assume I have mistyped the password, thus losing time and nerves by repeatedly retyping the password before thinking of the stray space character in front of the user name. :-) Wouldn't it be possible to remove leading spaces from the input in the user name field before matching user and password? Are leading spaces in user names even allowed? If so, unconditionally removing them could cause issues for people with such user names. These might be prevented, however, if the test was for a match of (password and username) OR (password and username without leading spaces), rather than just (password and username). Best regards, Andreas -- System Information: Debian Release: stretch/sid APT prefers unstable APT policy: (500, 'unstable') Architecture: i386 (i686) Kernel: Linux 3.16.0-4-686-pae (SMP w/4 CPU cores) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages lightdm-gtk-greeter depends on: ii libc6 2.19-18 ii libcairo2 1.14.0-2.1 ii libgdk-pixbuf2.0-0 2.31.1-2+b1 ii libglib2.0-02.44.0-3 ii libgtk-3-0 3.14.5-1 ii liblightdm-gobject-1-0 1.14.0-1 ii libx11-62:1.6.3-1 Versions of packages lightdm-gtk-greeter recommends: ii desktop-base 8.0.2 ii gnome-icon-theme-symbolic 3.12.0-1 pn gnome-themes-standard none ii policykit-10.105-8 lightdm-gtk-greeter suggests no packages. -- no debconf information -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
