gpgtools will have to update.

This is on purpose. Please read the discussions. Use card-timeout in scdaemon.conf or "gpgconf --kill scdaemon"

If this is gone in master, please close this bug. Thanks :).

Issue seems to be gone in gpg (GnuPG) 2.1.22-beta75

Specification is finished.

bit 0 (in smartcard context, we say b1 as it starts from 1) of Extended Capabilities specifies if KDF-DO is supported.

Tag for KDF-DO is assigned as:

Automatic creation of socket directories creates cleanup trouble for projects previously relying on the agent-shutdown if $GNUPGHOME is removed: https://notmuchmail.org/pipermail/notmuch/2017/024550.html

Here is the spec.

The debug log includes communication between host PC and the reader, thus, it may include your input of PIN when you do that.

Ping? Otherwise I would provide the required information.

By the commit: rGf053f99ed0b0: scd: Handle unexpected suspend/resume by CCID driver., I put some code to handle such an expected return from the device.
Please try.
I couldn't reproduce this on my machine. (Suspend-to-RAM keeps my USB device running.)

It looks like the device got suspended and resumed.
But the application (scdaemon) didn't get noticed by libusb.
So, scdaemon kept communicating as usual, but got unexpected msg type = 0x81,
which is error report status (RDR_to_PC_DataBlock).

FWIW, the syntax of "vendor-id:product-id" is used for USB for any USB tools.

In T3082#95656, @gniibe wrote:

Thank you for your comment.

I think that a practical approach for us would be having a list of vendor-id:product-id in a file under gnupg/doc/ and maintain the list.
It will be up to distributions to use the list to build hwdb, udev rules, or whatever.

Thank you for your comment.

In T3082#95636, @gniibe wrote:

(3) We don't know which smartcard reader works fine, while we know some readers don't work well.

While I understand your request, it's complicated.

No way to fix, itself. Better warning/error message can be done.

we are now at 2.1.20 - time to mark this one as resolved.

We also have a discussion of the mailing list. It does currently not make sense
to continue here.

The problem of NFS mounted home directories is _real_ and we have a solution for
this which is better than the old redirection hack.

The problem with too long socket names is not severe and has been around for
decades (for other software and 14 years for GnuPG). There are workaround and
/run/user also solves this.

I proposed a change which does not even require --create-socketdir. There was
no comment on this and thus I will push that now so that we can do a real life test.

Justus: I told you several times that we are not going to change working code
for no good reason.

Except that it is not working. If it was working, then
06f1f163e96f1039304fd3cf565cf9de1ca45849
would not be necessary.

Even if your hack (I call it a hack because it does not
work with getsockname)

1/ Yes it does. It returns precisely the path that was used in bind.

2/ We only use getsockname on sockets that were given us by a service manager
like systemd, and thus those sockets would be unaffected by "the hack".

would make it, it does not solve the major problem: The
inability of creating sockets on certain file systems. THAT is the major reason
why we moved to /var/run.

Please stop conflating these things. This bug is about "dirmngr and gpg-agent
should work automatically even when GNUPGHOME is larger than sun_path". It is
not about NFS or FAT or something.

Implemented in 2.1.19

Hello Werner,

The problem is, that some projects liek gpgtools for MacOS are reluctantly sticking to
gnupg-2.0 :-/

So, I'd love to have this patch committed in order to ease the transition phase from

2.0 to 2.1 for them.

Regards, Wolfgang

Justus: I told you several times that we are not going to change working code
for no good reason. Even if your hack (I call it a hack because it does not
work with getsockname) would make it, it does not solve the major problem: The
inability of creating sockets on certain file systems. THAT is the major reason
why we moved to /var/run.

The whole IPC thing is pretty complex and adding a non-standard hack as proposed
by Justus will for sure cause breakage on some platforms.

I'm not sure why you call it a hack. I've been looking at POSIX, [0] introduces
pathname resolution, and the terms 'relative path' and 'absolute path'.

0: http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13

Neither the page for connect [1], nor the one for bind [2] state that the path
used to connect/bind unix sockets must be an absolute path.

1: http: / / pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html#
2: http: / / pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html#

Furthermore, my test across a wide range of UNIX implementations did not show
any issues with using relative paths.

I agreed in T2964 (wk on Mar 01 2017, 07:31 AM / Roundup) to auto create socket directories. I would like to do that
only for a tmpfs but we can also try to do this always. Adding a inotify watch
to remove the directory is more complex and I am not sure whether this is really
needed. The other thing is simple and we could do that for 2.1.20.

The whole IPC thing is pretty complex and adding a non-standard hack as proposed
by Justus will for sure cause breakage on some platforms.

Yes, we should document /var/run recommendations in the README. I will do that
for the next release.

This bug report simply asks to solve the generic problem of GNUPGHOME being
larger than sun_path. Justus's proposed mechanism is only one way of solving
that problem.

Another proposed mechanism is what i originally proposed in T2964 (dkg on Feb 17 2017, 01:52 AM / Roundup), which
*does* address remote filesystems and re-mounted filesystems.

I don't undertstand the critique about the code not yet being mature. Code
doesn't become mature by not being written, it needs to be written first and
then tested in order to become mature.

Lastly, i think if we expect that /run/user/$(id -u)/ is a "simple dependency"
for building other software, we need to make that expectation explicit someplace
reasonable (e.g. doc/HACKING or something similar)

I've tried latest master and it no longer hangs for me.

Thanks. Changing the status to not-released as this is fixed.

My main reasons why I don't want to consider this now are:

• That code is not written and thus will not be matured.
• It does not solve the major problem why we moved to /var/run, namely remote file systems and avoidance of possible re-mounted file systems
• The claim that /var/run/user does not exists is not valid, because that is a simple dependency for building the software or using it with non-common setups (remot, long $HOME). Thus an admin will anyway be on duty and adding a few lines to /etc/rc.local is not a bug deal.

FWIW, we may try this in 2.3 see T2987.

Werner does not think that this is a problem and does not want me to spend time
on this.

getsockname is only used to recover the paths of sockets bound by a supervisor
like systemd. So unless systemd starts doing the same trick that I propose,
there is no problem.

This patch tried to fix the issue:
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=commit;h=f9acc7d18bb90f47dafe7e32ae92f567756d6b12

I was wrong that PIPE can be select(2)-ed on Windows. This patch changes the
code so that it uses kill(2) on UNIX and SetEvent on Windows
to break the loop.

With this patch the log message is different (No such file or directory). Hang
still happens.

2017-03-03 10:21:06 scdaemon[8604] DBG: enter: apdu_get_status: slot=0 hang=0
2017-03-03 10:21:06 scdaemon[8604] DBG: leave: apdu_get_status => sw=0x0 status=7
2017-03-03 10:21:06 scdaemon[8604] npth_pselect failed: No such file or
directory - waiting 1s

Version was 2.1.19 from the installer built by werner / the speedo system.

I'll try out the patch

It seems npth_eselect is for network FDs.

How about this change?

diff --git a/scd/scdaemon.c b/scd/scdaemon.c
index f7e9f83b5..462ff1b3e 100644

• a/scd/scdaemon.c

+++ b/scd/scdaemon.c
@@ -1291,7 +1291,7 @@ handle_connections (int listen_fd)

while (npth_sigev_get_pending(&signo))
  handle_signal (signo);

#else

• ret = npth_eselect (nfd+1, &read_fdset, NULL, NULL, t, NULL, NULL);

+ ret = npth_select (nfd+1, &read_fdset, NULL, NULL, t);

saved_errno = errno;

#endif

It is selecting FD which is created by gnupg_create_pipe.

Version information, please.

I cannot replicate this on GNU/Linux with PC/SC (by disable-ccid).
Anyway, I am looking into this issue:

npth_pselect failed: Input/output error - waiting 1s

I doubt that this is Windows only. On Linux we use our own driver but on
Windows we have to resort to PC/SC. My educated guess is that we are in some
blocking system call which is not npth_unprotected.

From what I've seen there is no variation in getsockname, it just returns
whatever path is passed to bind. I don't understand the need for getsockname
tbh, because we are the ones that bind the socket in the first place.

(The only variation seems to be that the function is broken on Hurd...).

Justus, thanks for this work, it's great!. If we can solve the problem by doing
more clever socket(7) manipulation, that would be a big win.

How do you propose dealing with the getsockname() variations? or should we just
forbid the use of getsockname() entirely in the gnupg codebase?

dkg, I understand that GnuPG does not work with such a homedir, however, it is
not the act of creating the socket that is problematic. In fact, both
bind(2)ing and connect(2)ing is ok if one uses relative paths, as demonstrated
by the test program I have attached here.

Here is the program binding and connecting to a socket with an absolute path
length of ~10 * sizeof sockaddr_un.sun_path:

System: OpenBSD:6.0:GENERIC.MP#1992
sizeof addr.sun_path: 104
Running test with strlen (cwd): 22, name: '/tmp/test-unix-sockets/socket'

getsockname returned '/tmp/test-unix-sockets/socket', addrlen: 106

Running test with strlen (cwd): 22, name: 'socket'

getsockname returned 'socket', addrlen: 106

Running test with strlen (cwd): 126, name: 'socket'

getsockname returned 'socket', addrlen: 106

Running test with strlen (cwd): 1062, name: 'socket'

  getsockname returned 'socket', addrlen: 106

This works on all Unices that I have access to. I've asked on gnupg-devel@ for
people to run it elsewhere.

I understand that '--create-socketdir' solves problems besides this one. But I
disagree with the statement that our handling of socket paths is unproblematic
because --create-socketdir solves this problem.

Can we test whether /run is mounted on a tmpfs ?
should we assume that /run is always on a tmpfs but /var/run is a classical Unix
w/o a tmpfs? Or is it better to have a configure option.

I can imagine to agree to auto-create the directory on a tmpfs.

Yes, notmuch decided that they needed to workaround the situation anyway,
because they're in an environment that doesn't create the standard per-user
rundir. That doesn't seem like a great argument that gpg should also fail in
environments where the standard per-user rundir is available. I can demonstrate
a number of environments where gpg or its daemons will fail, but i don't think
any of them justify forcing gpg or its daemons to *also* fail when those
environments aren't present.

In answer to your nitpick, here is evidence that gpg's daemons cannot create
their sockets when the GNUPGHOME is too long:

1 dkg@alice:~$ mkdir -m 0700
/home/dkg/tmp/very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long
0 dkg@alice:~$
GNUPGHOME=/home/dkg/tmp/very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-very-long
gpgconf --launch dirmngr
gpgconf: error running '/usr/bin/gpg-connect-agent': exit status 1
gpgconf: error running '/usr/bin/gpg-connect-agent --dirmngr NOP': General error
1 dkg@alice:~$

I'm having trouble decrypting some mails. I use an encryption sub-key with a
unusual length of 3104 bits. I described my problem in the gnupg-users mailing
list and there the following problem was identified:
<quote>
I think that it is deterministic; The cause is that the RSA keysize is
not the one in the set of: 1024, 1536, 2048, 3072, 4096. When data to
be decrypted is padded, scdaemon can't decrypt, I suppose.

I am not sure the exact reason why scdaemon only supports limited set of
keysize for encryption. But we have this handling of padding in the
current code:

https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=blob;f=scd/app-openpgp.c;h=71c9e1b83003af07b0984688ba1ec5e9013b877c;hb=refs/heads/master#l4334

       /* We might encounter a couple of leading zeroes in the
          cryptogram.  Due to internal use of MPIs these leading zeroes
          are stripped.  However the OpenPGP card expects exactly 128
          bytes for the cryptogram (for a 1k key).  Thus we need to fix
          it up.  We do this for up to 16 leading zero bytes; a
          cryptogram with more than this is with a very high
          probability anyway broken.  If a signed conversion was used
          we may also encounter one leading zero followed by the correct
          length.  We fix that as well.  */
       if (indatalen >= (128-16) && indatalen < 128)      /* 1024 bit key.  */
         fixuplen = 128 - indatalen;
       else if (indatalen >= (192-16) && indatalen < 192) /* 1536 bit key.  */
         fixuplen = 192 - indatalen;
       else if (indatalen >= (256-16) && indatalen < 256) /* 2048 bit key.  */
         fixuplen = 256 - indatalen;
       else if (indatalen >= (384-16) && indatalen < 384) /* 3072 bit key.  */
         fixuplen = 384 - indatalen;
       else if (indatalen >= (512-16) && indatalen < 512) /* 4096 bit key.  */
         fixuplen = 512 - indatalen;
       else if (!*(const char *)indata && (indatalen == 129
                                           || indatalen == 193
                                           || indatalen == 257
                                           || indatalen == 385
                                           || indatalen == 513))
         fixuplen = -1;
       else
         fixuplen = 0;

Perhaps, it was due to support all existing OpenPGP card
implementations, I mean, somehow historical, and it was easier to list
up specific keysizes.

This should be fixed.
</quote>

I also attached to log-files of the scdaemon. One for a successful and one for a
failed decryption attempt.

Please let me know if you need any additional information.

I tested with the GnuPG version 2.0.30 (GPG4WIn) as well as the current 2.1.16
Windows binaries. SCdaemon was running but was unable to get exclusive card access.
Why?
The Cisco Network Manager as well as Cisco Anyconnect VPN did both gain shared
card access (they were not told to do so!). I needed both programs to get access
to the university network.

Uninstalling both Programs and restarting did resolve the issue. To find the
two offenders I used Process Explorer (Processes for all users) and used the
Find Handle or DLL functon with the search term "SCARD". All crosschecked all
Processes (except for scdaemon which sould access the card) and Services
(svchost) to be only scdaemon aswell as the services to be Windows internal.
To determine the inital issue I used
https://sourceforge.net/projects/pcsctracker/ which told me the status of my
Yubikey (as Present,InUse -> Shared Access).

As a suggestion I like to see the experimental option to change the accessmode
from exclusive to shared on the commandline (If for example the other
application cannot be uninstalled).

Which version of GnuPG are you using? Do you have scdaemon?

Fixed in 2.1.16. Will be in 2.0.31 as the fix is in the git repo already.

Yeah, lets do that. Commit 8489b12 to go into 2.1.17. Thanks.

What about putting in the suggested patch as an intermediate step towards a full
solution?

Anything I can do to help?

I run in the same issue as PRab whenever I suspend or hibernate my machine. The
machine as Broadcom BCM5880 with a smart-card reader, so I cannot unplug it.
Quickest workaround is to kill/restart scdaemon.

Is there/could there be a command that could be sent to scdaemon via the agent
so a reset could be triggered? It should be easy enough to line that up as part
of the resume scripts.

Updated by the fix:

f9e49c8 scd: Fix an action after card removal.

Fixed in master:

    8fe8105 scd: Release the card reader after card removal.

In my environment, it works both for PC/SC and in-stock CCID driver.

Not yet for 2.0 and 1.4.

Ok, I can record such files. Will there be any confidential information contained in
these logs?

You can have a configuration file like:

.gnupg/gpg-agent.conf

enable-ssh-support
debug-level guru
debug-all

log-file /run/user/1000/gpg-agent.log

and

.gnupg/scdaemon.conf

debug-level guru
debug-all
debug-ccid-driver

log-file /run/user/1000/scd.log

so that the interactions can be recorded with debug information.