tang doesn't reply

[MAH69IK]

Hi!

My tang stopped working, although everything was fine a few days ago.

Service looks fine:

# systemctl status tangd.socket
● tangd.socket - Tang Server socket
   Loaded: loaded (/lib/systemd/system/tangd.socket; enabled; vendor preset: enabled)
   Active: active (listening) since Fri 2021-10-22 18:32:49 EEST; 24min ago
   Listen: [::]:80 (Stream)
 Accepted: 60595; Connected: 0; Refused: 12
    Tasks: 0 (limit: 4915)
   Memory: 44.0K
   CGroup: /system.slice/tangd.socket

Oct 22 18:32:49 tang-int systemd[1]: Listening on Tang Server socket.

But when I use tang-show-keys or curl 'http://<IP>/adv' I receive curl: (52) Empty reply from server.

Please help me with the diagnosis and correction of this problem. What do I need to do?

[eanow]

I'm having a similar issue. Tang quit responding after updating my system. My particular setup has tang running on a raspberry pi zero with raspbian buster.

I did a full rebuild of the raspberry, no luck. My ubuntu machine with tang running appears to work as expected.

On the raspberry (failing version), the package version is reported as:

Package: tang
Version: 7-1+deb10u1
Architecture: armhf
Maintainer: Christoph Biedl [email protected]
Installed-Size: 56
Depends: libc6 (>= 2.8), libhttp-parser2.8 (>= 2.1), libjansson4 (>= 2.10~), libjose0 (>= 10), jose
Homepage: https://github.com/latchset/tang
Priority: optional
Section: net
Filename: pool/main/t/tang/tang_7-1+deb10u1_armhf.deb
Size: 14036
SHA256: 1f935b5494ab5bccd51e449fcd6c1307439249fa2dd69041b2bccb7ecace4ff6
SHA1: 455e1ca916614076811db11d19f4d94b0e521a66
MD5sum: 2388fbc0af0272c4be1c1659fc566ae7
Description: network-based cryptographic binding server
Tang is a service for binding cryptographic keys to network presence.
It offers a secure, stateless, anonymous alternative to key escrow
services.
Description-md5: 5e2b4699be00ada48c869284534ea336

and on ubuntu (working) it is reported as:

Package: tang
Architecture: amd64
Version: 7-1build1
Priority: optional
Section: universe/net
Origin: Ubuntu
Maintainer: Ubuntu Developers [email protected]
Original-Maintainer: Christoph Biedl [email protected]
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Installed-Size: 65
Depends: libc6 (>= 2.8), libhttp-parser2.9 (>= 2.8.0), libjansson4 (>= 2.10~), libjose0 (>= 10), jose
Filename: pool/universe/t/tang/tang_7-1build1_amd64.deb
Size: 15008
MD5sum: 37eef10618eba2befb20ffb3675f6550
SHA1: c7dbfdcb7f91b5b9f4aea00b0420bc13c0f0f26f
SHA256: 13e2c323c1f9ff1217d31b078f34abb62273d7ab5cdb086132ebe0f6747a7d29
Homepage: https://github.com/latchset/tang
Description-en: network-based cryptographic binding server
Tang is a service for binding cryptographic keys to network presence.
It offers a secure, stateless, anonymous alternative to key escrow
services.
Description-md5: 5e2b4699be00ada48c869284534ea336

At this time, I'm not having luck downgrading the system (I know how to undo an update with RHEL/CENTOS, but not with debian based distros....) my /var/log/dpkg.log file suggests that tang wasn't actually touched in the last update, so I don't think it is a change in tang that triggered the error. libc6 and libhttp-parser were both updated in my most recent update (which broke tang)

[sergio-correia]

If libhttp-parser was updated, you may have to rebuild tang. @cbiedl: could you check this out, please?

[cbiedl]

The http-parser update in Debian 10 ("buster") broke tang. If the version number for libhttp-parser2.8 is something like "2.8.1-1+deb10u1", try a downgrade to the previous version, i.e. "2.8.1-1". Fix is underway.
Debian bugs: https://bugs.debian.org/996460 https://bugs.debian.org/996939

[eanow]

Appreciate the quick reponse. It appears that raspbian has already removed libhttp-parser2.8_2.8.1-1_armhf.deb from the main repository. I was able to locate a mirror which hasn't been updated recently, and had the older package still on it. Tang works with libhttp-parser downgraded, so that should work for me until the tang update is ready.

[dpantel]

thank you thank you thank you.

debian mirror that had an older version of libhttp-parser that worked for me on my pi:
https://snapshot.debian.org/package/http-parser/2.8.1-1/#libhttp-parser2.8_2.8.1-1

[stcz]

Same issue for me but workaround with downgrading http-parser is working.. :)