Openssl 3

Fri Jul 24 23:01:41 AEST 2020

On Fri, 24 Jul 2020 at 22:46, The Doctor <doctor at doctor.nl2k.ab.ca> wrote:
> Anyone trying openssl 3 against openssh?

I used to test OpenSSH head against OpenSSL head but it was broken
enough that I didn't have time to keep up and I ended up giving up.
Here's what I found as of a few months ago in case it provides any
clues, I have not attempted since then:

Several months ago a commit to OpenSSL head broke OpenSSH Portable's
AES-GCM ciphers.  I didn't have time to look at this for a while, and
by the time I did there were at least 2 other unrelated breakages that
muddied the waters sufficiently that I never got to the bottom of it.

I tried retesting at the hackathon and didn't get the results I
expected: now the GCM ones worked and the NON-GCM ones didn't

After some clues from tb and a lot of time bisecting I have identified
commits #1 and #3 below as the likely culprits.  I don't know if they
or we are doing the wrong thing.  Can anyone tell me?

Thanks.

Setup to reproduce these tests at the bottom.

Commit #1: This broke OpenSSH AES GCM ciphers:
a672a02a6443a29aa368c0d8abeebc809c1a9f28 is the first bad commit
commit a672a02a6443a29aa368c0d8abeebc809c1a9f28
Author: Shane Lontis <shane.lontis at oracle.com>
Date:   Wed Jul 31 21:55:16 2019 +1000

    Add gcm ciphers (aes and aria) to providers.

    The code has been modularized so that it can be shared by algorithms.

    A fixed size IV is now used instead of being allocated.
    The IV is not set into the low level struct now until the update (it uses an
    iv_state for this purpose).

    Hardware specific methods have been added to a PROV_GCM_HW object.

    The S390 code has been changed to just contain methods that can be
accessed in
    a modular way. There are equivalent generic methods also for the other
    platforms.

    Reviewed-by: Matt Caswell <matt at openssl.org>
    Reviewed-by: Patrick Steuer <patrick.steuer at de.ibm.com>
    (Merged from https://github.com/openssl/openssl/pull/9231)

result:
$ sh ../run.sh
run test dhgex.sh ...
dhgex bits 3072 diffie-hellman-group-exchange-sha1 3des-cbc
dhgex bits 3072 diffie-hellman-group-exchange-sha256 3des-cbc
dhgex bits 3072 diffie-hellman-group-exchange-sha1 aes128-gcm at openssh.com
ssh failed ()
dhgex bits 3072 diffie-hellman-group-exchange-sha256 aes128-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha1 aes256-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha256 aes256-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha1 rijndael-cbc at lysator.liu.se
dhgex bits 8192 diffie-hellman-group-exchange-sha256 rijndael-cbc at lysator.liu.se
dhgex bits 8192 diffie-hellman-group-exchange-sha1 chacha20-poly1305 at openssh.com
dhgex bits 8192 diffie-hellman-group-exchange-sha256
chacha20-poly1305 at openssh.com
failed dhgex

Commit #2: The Red Herring. This broke building without engine.
commit 2f17cc493cfaa5c77a77d4f174dd2403188c41da
Author: Pauli <paul.dale at oracle.com>
Date:   Thu Sep 5 13:53:20 2019 +1000

    Unify the digest getting code inside providers.

    Reviewed-by: Richard Levitte <levitte at openssl.org>
    (Merged from https://github.com/openssl/openssl/pull/9770)

Commit #3:  This commit broke the non-GCM ciphers.

commit 089cb623be76b88a1eea6fcd135101037661bbc3
Author: Shane Lontis <shane.lontis at oracle.com>
Date:   Tue Oct 8 09:19:10 2019 +1000

    Move cipher ctx 'original iv' parameter into the provider

    Reviewed-by: Richard Levitte <levitte at openssl.org>
    (Merged from https://github.com/openssl/openssl/pull/10026)

run test dhgex.sh ...
dhgex bits 3072 diffie-hellman-group-exchange-sha1 3des-cbc
ssh failed ()
dhgex bits 3072 diffie-hellman-group-exchange-sha256 3des-cbc
ssh failed ()
dhgex bits 3072 diffie-hellman-group-exchange-sha1 aes128-gcm at openssh.com
ssh failed ()
dhgex bits 3072 diffie-hellman-group-exchange-sha256 aes128-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha1 aes256-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha256 aes256-gcm at openssh.com
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha1 rijndael-cbc at lysator.liu.se
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha256 rijndael-cbc at lysator.liu.se
ssh failed ()
dhgex bits 8192 diffie-hellman-group-exchange-sha1 chacha20-poly1305 at openssh.com
dhgex bits 8192 diffie-hellman-group-exchange-sha256
chacha20-poly1305 at openssh.com
failed dhgex

Environment setup on OpenBSD:
git clone https://github.com/openssh/openssh-portable.git openssh
git clone https://github.com/openssl/openssl.git openssl
(cd openssh && AUTOCONF_VERSION=2.69 autoreconf)
cat >run.sh <<EOD
#!/bin/sh
set -e

rm -rf ~/tmp/openssl-install
LDLIBS=-lc ./config no-threads no-fips no-engine --prefix=~/tmp/openssl-install
make clean
make
make install_sw

(cd ../openssh &&
./configure --with-ssl-dir=~/tmp/openssl-install --with-rpath=-Wl,-rpath, &&
make clean &&
make -j4 &&
make t-exec LTESTS="dhgex")
EOD

-- 
Darren Tucker (dtucker at dtucker.net)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.