libgnutls30 OCSP verification bug

[largeprime]

[Impact]

Applications using GnuTLS fails to verify OSCP, especially when ECDSA is involved, which becomes increasingly more popular.

[Test Case]
Run "gnutls-cli -p 443 tvemsnbc-vh.akamaihd.net" - it should succeed (hang once connected, basically), but fails the handshake with certificate validation.

[Regression Potential]
Only OCSP code is affected by the fixes, so something could possibly break there.

[Other Info]
This was fixed in Debian stretch in 3.5.8-5+deb9u3:

https://anonscm.debian.org/cgit/pkg-gnutls/gnutls.git/commit/?h=gnutls28_09_stretch&id=aebb4e1b78758d6395e17a3137f2c67a2fb7a334

[Julian Andres Klode (juliank)]

JFTR: xenial is not affected, I assume older versions are not either.

[Julian Andres Klode (juliank)]

Fixes for both artful and zesty are uploaded now.

[Launchpad Janitor (janitor)]

This bug was fixed in the package gnutls28 - 3.5.8-6ubuntu3

---------------
gnutls28 (3.5.8-6ubuntu3) artful; urgency=medium

  * Cherry pick several fixes from Debian 3.5.8-5+deb9u3:
    - 38_01-OCSP-check-the-subject-public-key-identifier-field-t.patch
      38_02-OCSP-find_signercert-improved-DER-length-calculation.patch from
      gnutls 3.5.14: Fix OCSP verification errors, especially with ecdsa
      signatures. LP: #1714506
    - 37_aarch64-fix-AES-GCM-in-place-encryption-and-decrypti.patch from
      upstream 3.5.x branch: Fix breakage if AES-GCM in-place encryption and
      decryption on aarch64. LP: #1707172

 -- Julian Andres Klode <email address hidden> Sat, 02 Sep 2017 16:12:49 +0200

[Andy Whitcroft (apw)]

Hello largeprime, or anyone else affected,

Accepted gnutls28 into zesty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/gnutls28/3.5.6-4ubuntu4.3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-zesty to verification-done-zesty. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-zesty. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Julian Andres Klode (juliank)]

Verified on zesty, old version 3.5.6-4ubuntu4.2 failed handshake, 3.5.6-4ubuntu4.3 succeeded:

Script started on Thu 07 Sep 2017 00:45:28 CEST
+ apt-get -q update
[...]
+ apt-get -q -y install gnutls-bin ca-certificates
Reading package lists...
Building dependency tree...
Reading state information...
The following additional packages will be installed:
  libffi6 libgmp10 libgnutls30 libhogweed4 libidn11 libnettle6 libopts25 libp11-kit0 libssl1.0.0 libtasn1-6 openssl
The following NEW packages will be installed:
  ca-certificates gnutls-bin libffi6 libgmp10 libgnutls30 libhogweed4 libidn11 libnettle6 libopts25 libp11-kit0 libssl1.0.0 libtasn1-6 openssl
0 upgraded, 13 newly installed, 0 to remove and 0 not upgraded.
Need to get 3326 kB of archives.
After this operation, 9762 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu zesty/main amd64 libffi6 amd64 3.2.1-6 [17.7 kB]
Get:2 http://archive.ubuntu.com/ubuntu zesty/main amd64 libgmp10 amd64 2:6.1.2+dfsg-1 [240 kB]
Get:3 http://archive.ubuntu.com/ubuntu zesty/main amd64 libnettle6 amd64 3.3-1 [92.4 kB]
Get:4 http://archive.ubuntu.com/ubuntu zesty/main amd64 libhogweed4 amd64 3.3-1 [135 kB]
Get:5 http://archive.ubuntu.com/ubuntu zesty/main amd64 libidn11 amd64 1.33-1 [45.0 kB]
Get:6 http://archive.ubuntu.com/ubuntu zesty/main amd64 libp11-kit0 amd64 0.23.3-5 [107 kB]
Get:7 http://archive.ubuntu.com/ubuntu zesty-updates/main amd64 libtasn1-6 amd64 4.10-1ubuntu0.1 [35.5 kB]
Get:8 http://archive.ubuntu.com/ubuntu zesty-updates/main amd64 libgnutls30 amd64 3.5.6-4ubuntu4.2 [627 kB]
Get:9 http://archive.ubuntu.com/ubuntu zesty-updates/main amd64 libssl1.0.0 amd64 1.0.2g-1ubuntu11.2 [1081 kB]
Get:10 http://archive.ubuntu.com/ubuntu zesty-updates/main amd64 openssl amd64 1.0.2g-1ubuntu11.2 [491 kB]
Get:11 http://archive.ubuntu.com/ubuntu zesty/main amd64 ca-certificates all 20161130 [193 kB]
Get:12 http://archive.ubuntu.com/ubuntu zesty/main amd64 libopts25 amd64 1:5.18.12-3 [57.0 kB]
Get:13 http://archive.ubuntu.com/ubuntu zesty-updates/universe amd64 gnutls-bin amd64 3.5.6-4ubuntu4.2 [204 kB]
Fetched 3326 kB in 2s (1539 kB/s)
[...]
+ gnutls-cli -p 443 tvemsnbc-vh.akamaihd.net
Processed 173 CA certificate(s).
Resolving 'tvemsnbc-vh.akamaihd.net:443'...
Connecting to '95.101.77.25:443'...
- Certificate type: X.509
- Got a certificate list of 2 certificates.
- Certificate[0] info:
 - subject `CN=a248.e.akamai.net,O=Akamai Technologies\, Inc.,L=Cambridge,ST=Massachusetts,C=US', issuer `CN=Symantec Class 3 ECC 256 bit SSL CA - G2,OU=Symantec Trust Network,O=Symantec Corporation,C=US', serial 0x0f683f2dfac9edf014148ca649db4bad, EC/ECDSA key 256 bits, signed using ECDSA-SHA256, activated `2017-03-07 00:00:00 UTC', expires `2018-05-06 23:59:59 UTC', SHA-1 fingerprint `557c90a8d8953f3a2c2b59290a5ce12eafa60adf'
 Public Key ID:
  8c08394d28e104af81d099d4d236eef424710a29
 Public key's random art:
  +--[SECP256R1]----+
  |==.B. |
  |E.O+* . |
  |o+==.= |
  | o o=..o |
  |. o.+. S |
  | . . |
  | |
  | |
  | |
  +-----------------+

- Certificate[1] info:
 - subject `CN=Symantec ...

[largeprime (largeprime)]

Verifyed working on zesty

Bug was discovered using vlc to access web stream needing tls auth. Debuging pointed at gnutls. Bug resolved after upgrade to patched gnutls.

Thanks

[Launchpad Janitor (janitor)]

This bug was fixed in the package gnutls28 - 3.5.6-4ubuntu4.3

---------------
gnutls28 (3.5.6-4ubuntu4.3) zesty; urgency=medium

  * Cherry pick several fixes from Debian 3.5.8-5+deb9u3:
    - 38_01-OCSP-check-the-subject-public-key-identifier-field-t.patch
      38_02-OCSP-find_signercert-improved-DER-length-calculation.patch from
      gnutls 3.5.14: Fix OCSP verification errors, especially with ecdsa
      signatures. LP: #1714506
    - 37_aarch64-fix-AES-GCM-in-place-encryption-and-decrypti.patch from
      upstream 3.5.x branch: Fix breakage if AES-GCM in-place encryption and
      decryption on aarch64. LP: #1707172

 -- Julian Andres Klode <email address hidden> Sat, 02 Sep 2017 16:12:49 +0200

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for gnutls28 has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.