Bug#912864: openssl: new version of openssl breaks some openvpn clients

2019-02-07 Thread James Bottomley
On Thu, 2019-02-07 at 22:55 +0100, Jean-Marc wrote:
> On Mon, 26 Nov 2018 23:41:13 +0100 Sebastian Andrzej Siewior  a...@breakpoint.cc> wrote:
> > On 2018-11-04 22:15:04 [+0100], Kurt Roeckx wrote:
> > > > You're implying openvpn doesn't pick up the openssl.cnf changes
> > > > so I have to set tls-version-min 1.0 in the server side
> > > > configuration?  OK, that works too.  
> > > 
> > > Your client doesn't support the settings in the openssl.cfg file.
> > > Your openvpn client by defaults does TLS 1.0 only. The only way
> > > for your client to do something other than TLS 1.0 is set the
> > > tls-version-min variable to something. If you set it to 1.0, it
> > > will do any version supported by the openssl library higher than
> > > 1.0.
> > 
> > James, is everything okay/clear? The tls-version-min option for the
> > older OpenVPN version should have fixed things. Is there anything
> > else or can this be considered done?
> > 
> > > Kurt
> > 
> > Sebastian
> 
> Hi James,
> 
> May I ask you if you got all the answers you needed and if it fixed
> the problem.

Yes, I said that in the initial quote: setting tls-version-min in
openssl.cnf works, and that's what I've done.  It's just unexpected
that you have to update your openvpn config files.

James


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Bug#912864: openssl: new version of openssl breaks some openvpn clients

2019-02-07 Thread Jean-Marc
On Mon, 26 Nov 2018 23:41:13 +0100 Sebastian Andrzej Siewior 
 wrote:
> On 2018-11-04 22:15:04 [+0100], Kurt Roeckx wrote:
> > > You're implying openvpn doesn't pick up the openssl.cnf changes so I
> > > have to set tls-version-min 1.0 in the server side configuration?  OK,
> > > that works too.  
> > 
> > Your client doesn't support the settings in the openssl.cfg file. Your
> > openvpn client by defaults does TLS 1.0 only. The only way for your client
> > to do something other than TLS 1.0 is set the tls-version-min variable
> > to something. If you set it to 1.0, it will do any version
> > supported by the openssl library higher than 1.0.
> 
> James, is everything okay/clear?
> The tls-version-min option for the older OpenVPN version should have
> fixed things.
> Is there anything else or can this be considered done?
> 
> > Kurt
> 
> Sebastian

Hi James,

May I ask you if you got all the answers you needed and if it fixed the problem.

Thank you so much.

Regards,

Jean-Marc 
https://6jf.be/keys/ED863AD1.txt


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Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-26 Thread Sebastian Andrzej Siewior
On 2018-11-04 22:15:04 [+0100], Kurt Roeckx wrote:
> > You're implying openvpn doesn't pick up the openssl.cnf changes so I
> > have to set tls-version-min 1.0 in the server side configuration?  OK,
> > that works too.  
> 
> Your client doesn't support the settings in the openssl.cfg file. Your
> openvpn client by defaults does TLS 1.0 only. The only way for your client
> to do something other than TLS 1.0 is set the tls-version-min variable
> to something. If you set it to 1.0, it will do any version
> supported by the openssl library higher than 1.0.

James, is everything okay/clear?
The tls-version-min option for the older OpenVPN version should have
fixed things.
Is there anything else or can this be considered done?

> Kurt

Sebastian



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 12:49:48PM -0800, James Bottomley wrote:
> On Sun, 2018-11-04 at 21:30 +0100, Kurt Roeckx wrote:
> > On Sun, Nov 04, 2018 at 12:13:43PM -0800, James Bottomley wrote:
> > > 
> > > No, I'm saying with no client tls-version-min specified at all (the
> > > usual default openvpn config) it fails in 1.1.1 and works with
> > > 1.1.0
> > > 
> > > With client tls-version-min set to 1.0 it works with both.
> > 
> > Yes, and that's totally what I expected, and have been explaining.
> > The 2.3.X version only want to do TLS 1.0 unless you specify
> > "tls-version-min 1.0", in which case they also do TLS 1.2.
> 
> You're implying openvpn doesn't pick up the openssl.cnf changes so I
> have to set tls-version-min 1.0 in the server side configuration?  OK,
> that works too.  

Your client doesn't support the settings in the openssl.cfg file. Your
openvpn client by defaults does TLS 1.0 only. The only way for your client
to do something other than TLS 1.0 is set the tls-version-min variable
to something. If you set it to 1.0, it will do any version
supported by the openssl library higher than 1.0.

> > So I'm failing to see what this bug report is about.
> 
> When you upgrade from openssl 1.1.0 to 1.1.1 causes an openvpn
> connection failure which the upgrade instructions don't fix.  It also
> seems to me there are probably quite a few other openssl.cnf blind
> applications in the system which will fail in a similar fashion.

This is on the server side. As far as I know, changing the
openssl.cnf file should just work. openvpn in testing takes the
minimum of the openssl.cfg value and TLS 1.0. So if you set None,
it should set TLS 1.0 as minimum. I assume you don't set a minimum
tls version in your openvpn config file or on the command line.


Kurt



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
On Sun, 2018-11-04 at 21:30 +0100, Kurt Roeckx wrote:
> On Sun, Nov 04, 2018 at 12:13:43PM -0800, James Bottomley wrote:
> > 
> > No, I'm saying with no client tls-version-min specified at all (the
> > usual default openvpn config) it fails in 1.1.1 and works with
> > 1.1.0
> > 
> > With client tls-version-min set to 1.0 it works with both.
> 
> Yes, and that's totally what I expected, and have been explaining.
> The 2.3.X version only want to do TLS 1.0 unless you specify
> "tls-version-min 1.0", in which case they also do TLS 1.2.

You're implying openvpn doesn't pick up the openssl.cnf changes so I
have to set tls-version-min 1.0 in the server side configuration?  OK,
that works too.  

> So I'm failing to see what this bug report is about.

When you upgrade from openssl 1.1.0 to 1.1.1 causes an openvpn
connection failure which the upgrade instructions don't fix.  It also
seems to me there are probably quite a few other openssl.cnf blind
applications in the system which will fail in a similar fashion.

James



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 12:13:43PM -0800, James Bottomley wrote:
> 
> No, I'm saying with no client tls-version-min specified at all (the
> usual default openvpn config) it fails in 1.1.1 and works with 1.1.0
> 
> With client tls-version-min set to 1.0 it works with both.

Yes, and that's totally what I expected, and have been explaining.
The 2.3.X version only want to do TLS 1.0 unless you specify
"tls-version-min 1.0", in which case they also do TLS 1.2.

So I'm failing to see what this bug report is about.


Kurt



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
On Sun, 2018-11-04 at 21:10 +0100, Kurt Roeckx wrote:
> On Sun, Nov 04, 2018 at 11:39:59AM -0800, James Bottomley wrote:
> > > 
> > > On which side do you use tls-version-min?
> > 
> > client
> > 
> > >  Can you please give the version of both openvpn and openssl on
> > > both
> > > sides.
> > 
> > Client is openwrt, server is debian testing.  The package of the
> > server
> > was already provided in the bug report, but again it's
> > 
> > openssl 1.1.1-2
> > openvpn 2.4.6-1
> > 
> > Packages on the openwrt client are
> > 
> > libopenssl 1.0.2g-1
> > openvpn-openssl  2.3.6-5
> 
> So you're saying that even with tls-version-min 1.0 on your
> client side and with openssl.cnf changed on the server it's still
> not working?

No, I'm saying with no client tls-version-min specified at all (the
usual default openvpn config) it fails in 1.1.1 and works with 1.1.0

With client tls-version-min set to 1.0 it works with both.

James



Bug#912864: [Pkg-openssl-devel] Bug#912864: Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Sebastian Andrzej Siewior
On 2018-11-04 11:39:59 [-0800], James Bottomley wrote:
> > > OK, so I'm weary of trying to construct a theory of what the bug
> > > actually is, why don't you try to come up with one.  The symptoms
> > > are
> > > that openvpn in openwrt works with server 1.1.0 and fails with
> > > server
> > > 1.1.1 if you don't specify tls-version-min 1.0 on the command line.
> > 
> > On which side do you use tls-version-min?
> 
> client
> 
> >  Can you please give the version of both openvpn and openssl on both
> > sides.
> 
> Client is openwrt, server is debian testing.  The package of the server
> was already provided in the bug report, but again it's
> 
> openssl 1.1.1-2
> openvpn 2.4.6-1
> 
> Packages on the openwrt client are
> 
> libopenssl 1.0.2g-1
> openvpn-openssl  2.3.6-5

That matches what I see. The Jessie version (which matches your openwrt
client) does TLSv1.0 only by default. If you specify tls-version-min
(even 1.0) then it tries 1.0+ and does the best possible protocol which
is TLS1.2 in my case.
Stretch seems to do the best possible version by default.
Buster/Testing has TLS1.0 disabled by default.
So in your environment the client tries TLS1.0 only and server does
TLS1.2 only. Adding tls-version-min on the client side enables
TLS1.0+ and handshakes with TLS1.2.

This behaviour has been reported as #912650 on the Debian side.

> James

Sebastian



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 11:39:59AM -0800, James Bottomley wrote:
> > 
> > On which side do you use tls-version-min?
> 
> client
> 
> >  Can you please give the version of both openvpn and openssl on both
> > sides.
> 
> Client is openwrt, server is debian testing.  The package of the server
> was already provided in the bug report, but again it's
> 
> openssl 1.1.1-2
> openvpn 2.4.6-1
> 
> Packages on the openwrt client are
> 
> libopenssl 1.0.2g-1
> openvpn-openssl  2.3.6-5

So you're saying that even with tls-version-min 1.0 on your
client side and with openssl.cnf changed on the server it's still
not working? Either of those changes should be enough to get it
working as far as I understand.

I have almost the reverse in my setup, where the server is 2.3.4
and the client runs testing. On the server I've set the
tls-version-min 1.0 and everything works for me.

I will try to look at this in a few days.


Kurt



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
On Sun, 2018-11-04 at 20:32 +0100, Kurt Roeckx wrote:
> On Sun, Nov 04, 2018 at 11:19:41AM -0800, James Bottomley wrote:
> > On Sun, 2018-11-04 at 20:15 +0100, Kurt Roeckx wrote:
> > > This is not at all how the version negiotation in TLS 1.2 and
> > > below works. The client just indicates the highest version it
> > > supports, so for instance TLS 1.2. It's then up to the server to
> > > pick a version that the client supports, so one that is smaller
> > > than
> > > TLS 1.2, and it might pick TLS 1.0 or 1.2. It will then send a
> > > server
> > > hello with that version.
> > 
> > OK, so I'm weary of trying to construct a theory of what the bug
> > actually is, why don't you try to come up with one.  The symptoms
> > are
> > that openvpn in openwrt works with server 1.1.0 and fails with
> > server
> > 1.1.1 if you don't specify tls-version-min 1.0 on the command line.
> 
> On which side do you use tls-version-min?

client

>  Can you please give the version of both openvpn and openssl on both
> sides.

Client is openwrt, server is debian testing.  The package of the server
was already provided in the bug report, but again it's

openssl 1.1.1-2
openvpn 2.4.6-1

Packages on the openwrt client are

libopenssl 1.0.2g-1
openvpn-openssl  2.3.6-5

James



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 11:19:41AM -0800, James Bottomley wrote:
> On Sun, 2018-11-04 at 20:15 +0100, Kurt Roeckx wrote:
> > This is not at all how the version negiotation in TLS 1.2 and
> > below works. The client just indicates the highest version it
> > supports, so for instance TLS 1.2. It's then up to the server to
> > pick a version that the client supports, so one that is smaller than
> > TLS 1.2, and it might pick TLS 1.0 or 1.2. It will then send a server
> > hello with that version.
> 
> OK, so I'm weary of trying to construct a theory of what the bug
> actually is, why don't you try to come up with one.  The symptoms are
> that openvpn in openwrt works with server 1.1.0 and fails with server
> 1.1.1 if you don't specify tls-version-min 1.0 on the command line.

On which side do you use tls-version-min? Can you please give the
version of both openvpn and openssl on both sides.


Kurt



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
On Sun, 2018-11-04 at 20:15 +0100, Kurt Roeckx wrote:
> This is not at all how the version negiotation in TLS 1.2 and
> below works. The client just indicates the highest version it
> supports, so for instance TLS 1.2. It's then up to the server to
> pick a version that the client supports, so one that is smaller than
> TLS 1.2, and it might pick TLS 1.0 or 1.2. It will then send a server
> hello with that version.

OK, so I'm weary of trying to construct a theory of what the bug
actually is, why don't you try to come up with one.  The symptoms are
that openvpn in openwrt works with server 1.1.0 and fails with server
1.1.1 if you don't specify tls-version-min 1.0 on the command line.

> So there are normally 2 cases that can be a problem:
> - The client sends TLS 1.0 and the server has 1.2 as minimum, so
>   the server say it's not supported.
> - The client sends TLS 1.2, the server answers with 1.0, the
>   client says 1.0 is too low.
> 
> The error message you showed says that it's the server that is
> rejecting the client's version, and that the server is running a
> 1.1.1 version. Are you sure you've actually restarted the server
> after changing the config file?

Yes, the server got rebooted after the upgrade.

James



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 10:19:00AM -0800, James Bottomley wrote:
> On Sun, 2018-11-04 at 18:43 +0100, Kurt Roeckx wrote:
> > Older versions of openvpn only support TLS 1.0 because they told
> > OpenSSL to only use TLS 1.0. Adding the --tls-version-min 1.0
> > should make it support all TLS versions since openvpn 2.3.4 or
> > something like that, and I think 2.4 or newer should just work.
> 
> There's a difference: if you don't specify the command line tls-
> version-min, it actually asks openssl for the minimum version.  If you
> do specify, it takes what you tell it.

There is no API in OpenSSL to ask the minimum supported version.
What 2.3.4 does is that if you don't specify anything, it tells
OpenSSL to use TLS 1.0 only. What 2.4 does it just tell OpenSSL to
use any version it supports.

You can also specify that minimum version in the config file.

> > But if you changed the openssl.cfg to say all versions are
> > supported, it should work too, I'm not sure why you say otherwise.
> 
> Well, obviously because it doesn't work as the log attached in the bug
> report shows.
> 
> The values I have in openssl.cnf are the recommended
> 
> MinProtocol = None
> CipherString = DEFAULT
> 
> And it definitely works because imap has an android client at 0.9.8
> which didn't work before the addition of that.
> 
> The openssl code looks to use SSL_CTX_get_min_proto_version() if you
> don't specify a version, so it finds a protocol below tls 1.0 to
> present which causes the error.  From the ordering in openssl, this is
> likely to be SSLv3, isn't it?

With the above config SSL_CTX_get_min_proto_version() will return
0 indicating that all version supported at compile time are
supported. The minium at compile time is TLS 1.0.

> The bug here is that you shouldn't kill the negotiation just because
> the client offers to support SSLv3, you should move on to negotiate a
> more secure cipher and only error out if the client can't support any
> protocols openssl is told to consider secure.

This is not at all how the version negiotation in TLS 1.2 and
below works. The client just indicates the highest version it
supports, so for instance TLS 1.2. It's then up to the server to
pick a version that the client supports, so one that is smaller than
TLS 1.2, and it might pick TLS 1.0 or 1.2. It will then send a server
hello with that version.

So there are normally 2 cases that can be a problem:
- The client sends TLS 1.0 and the server has 1.2 as minimum, so
  the server say it's not supported.
- The client sends TLS 1.2, the server answers with 1.0, the
  client says 1.0 is too low.

The error message you showed says that it's the server that is
rejecting the client's version, and that the server is running a
1.1.1 version. Are you sure you've actually restarted the server
after changing the config file?


Kurt



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
On Sun, 2018-11-04 at 18:43 +0100, Kurt Roeckx wrote:
> Older versions of openvpn only support TLS 1.0 because they told
> OpenSSL to only use TLS 1.0. Adding the --tls-version-min 1.0
> should make it support all TLS versions since openvpn 2.3.4 or
> something like that, and I think 2.4 or newer should just work.

There's a difference: if you don't specify the command line tls-
version-min, it actually asks openssl for the minimum version.  If you
do specify, it takes what you tell it.

> But if you changed the openssl.cfg to say all versions are
> supported, it should work too, I'm not sure why you say otherwise.

Well, obviously because it doesn't work as the log attached in the bug
report shows.

The values I have in openssl.cnf are the recommended

MinProtocol = None
CipherString = DEFAULT

And it definitely works because imap has an android client at 0.9.8
which didn't work before the addition of that.

The openssl code looks to use SSL_CTX_get_min_proto_version() if you
don't specify a version, so it finds a protocol below tls 1.0 to
present which causes the error.  From the ordering in openssl, this is
likely to be SSLv3, isn't it?

The bug here is that you shouldn't kill the negotiation just because
the client offers to support SSLv3, you should move on to negotiate a
more secure cipher and only error out if the client can't support any
protocols openssl is told to consider secure.

James



Bug#912864: [Pkg-openssl-devel] Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread Kurt Roeckx
On Sun, Nov 04, 2018 at 08:59:05AM -0800, James Bottomley wrote:
> Package: openssl
> Version: 1.1.1-2
> Severity: important
> 
> I've applied all the downgrades recommended to the openssl.cnf file
> and most services are now working again with the exception of openvpn.
> 
> The only failure seems to be a VPN connection to an openwrt router.
> The router is running Chaos Calmer 15.05 and has an upgraded openssl
> (to 1.0.2g-1).
> 
> The error is on the debian server side and only shows up at openvpn
> extreme verbosity:
> 
> Sun Nov  4 08:40:04 2018 us=149552 50.35.68.20:56038 OpenSSL: 
> error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported 
> protocol
> 
> The full verbose negotiation is
> 
> Sun Nov  4 08:40:04 2018 us=116122 50.35.68.20:56038 Control Channel MTU 
> parms [ L:1621 D:1212 EF:38 EB:0 ET:0 EL:3 ]
> Sun Nov  4 08:40:04 2018 us=116160 50.35.68.20:56038 Data Channel MTU parms [ 
> L:1621 D:1450 EF:121 EB:406 ET:0 EL:3 ]
> Sun Nov  4 08:40:04 2018 us=116243 50.35.68.20:56038 Local Options String 
> (VER=V4): 'V4,dev-type tun,link-mtu 1557,tun-mtu 1500,proto UDPv4,cipher 
> AES-128-CBC,auth SHA1,keysize 128,key-method 2,tls-server'
> Sun Nov  4 08:40:04 2018 us=116263 50.35.68.20:56038 Expected Remote Options 
> String (VER=V4): 'V4,dev-type tun,link-mtu 1557,tun-mtu 1500,proto 
> UDPv4,cipher AES-128-CBC,auth SHA1,keysize 128,key-method 2,tls-client'
> RSun Nov  4 08:40:04 2018 us=116336 50.35.68.20:56038 TLS: Initial packet 
> from [AF_INET]50.35.68.20:56038, sid=812b650a 26613bfb
> WRRWRSun Nov  4 08:40:04 2018 us=149552 50.35.68.20:56038 OpenSSL: 
> error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported 
> protocol
> Sun Nov  4 08:40:04 2018 us=150331 50.35.68.20:56038 TLS_ERROR: BIO read 
> tls_read_plaintext error
> Sun Nov  4 08:40:04 2018 us=150984 50.35.68.20:56038 TLS Error: TLS object -> 
> incoming plaintext read error
> Sun Nov  4 08:40:04 2018 us=151598 50.35.68.20:56038 TLS Error: TLS handshake 
> failed
> Sun Nov  4 08:40:04 2018 us=152357 50.35.68.20:56038 SIGUSR1[soft,tls-error] 
> received, client-instance restarting
> 
> Obviously this was all working with 1.1.0 so something seems to have
> changed in the tls negotiation routines.
> 
> I can fix this in the client by adding the openssl command
> --tls-version-min 1.0 so it probably means, the way openvpn works that
> the openssl version installed in openwrt has some strange TLS version
> < 1.0 but clearly openssl shouldn't error out when presented with
> lower ciphers it should negotiate the mutually acceptable version.

Older versions of openvpn only support TLS 1.0 because they told
OpenSSL to only use TLS 1.0. Adding the --tls-version-min 1.0
should make it support all TLS versions since openvpn 2.3.4 or
something like that, and I think 2.4 or newer should just work.

But if you changed the openssl.cfg to say all versions are
supported, it should work too, I'm not sure why you say otherwise.


Kurt



Bug#912864: openssl: new version of openssl breaks some openvpn clients

2018-11-04 Thread James Bottomley
Package: openssl
Version: 1.1.1-2
Severity: important

I've applied all the downgrades recommended to the openssl.cnf file
and most services are now working again with the exception of openvpn.

The only failure seems to be a VPN connection to an openwrt router.
The router is running Chaos Calmer 15.05 and has an upgraded openssl
(to 1.0.2g-1).

The error is on the debian server side and only shows up at openvpn
extreme verbosity:

Sun Nov  4 08:40:04 2018 us=149552 50.35.68.20:56038 OpenSSL: 
error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported 
protocol

The full verbose negotiation is

Sun Nov  4 08:40:04 2018 us=116122 50.35.68.20:56038 Control Channel MTU parms 
[ L:1621 D:1212 EF:38 EB:0 ET:0 EL:3 ]
Sun Nov  4 08:40:04 2018 us=116160 50.35.68.20:56038 Data Channel MTU parms [ 
L:1621 D:1450 EF:121 EB:406 ET:0 EL:3 ]
Sun Nov  4 08:40:04 2018 us=116243 50.35.68.20:56038 Local Options String 
(VER=V4): 'V4,dev-type tun,link-mtu 1557,tun-mtu 1500,proto UDPv4,cipher 
AES-128-CBC,auth SHA1,keysize 128,key-method 2,tls-server'
Sun Nov  4 08:40:04 2018 us=116263 50.35.68.20:56038 Expected Remote Options 
String (VER=V4): 'V4,dev-type tun,link-mtu 1557,tun-mtu 1500,proto UDPv4,cipher 
AES-128-CBC,auth SHA1,keysize 128,key-method 2,tls-client'
RSun Nov  4 08:40:04 2018 us=116336 50.35.68.20:56038 TLS: Initial packet from 
[AF_INET]50.35.68.20:56038, sid=812b650a 26613bfb
WRRWRSun Nov  4 08:40:04 2018 us=149552 50.35.68.20:56038 OpenSSL: 
error:14209102:SSL routines:tls_early_post_process_client_hello:unsupported 
protocol
Sun Nov  4 08:40:04 2018 us=150331 50.35.68.20:56038 TLS_ERROR: BIO read 
tls_read_plaintext error
Sun Nov  4 08:40:04 2018 us=150984 50.35.68.20:56038 TLS Error: TLS object -> 
incoming plaintext read error
Sun Nov  4 08:40:04 2018 us=151598 50.35.68.20:56038 TLS Error: TLS handshake 
failed
Sun Nov  4 08:40:04 2018 us=152357 50.35.68.20:56038 SIGUSR1[soft,tls-error] 
received, client-instance restarting

Obviously this was all working with 1.1.0 so something seems to have
changed in the tls negotiation routines.

I can fix this in the client by adding the openssl command
--tls-version-min 1.0 so it probably means, the way openvpn works that
the openssl version installed in openwrt has some strange TLS version
< 1.0 but clearly openssl shouldn't error out when presented with
lower ciphers it should negotiate the mutually acceptable version.

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing'), (500, 'stable')
Architecture: i386 (i686)

Kernel: Linux 4.18.0-2-686 (SMP w/1 CPU core)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), 
LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages openssl depends on:
ii  libc6  2.27-8
ii  libssl1.1  1.1.1-2

openssl recommends no packages.

Versions of packages openssl suggests:
ii  ca-certificates  20170717

-- Configuration Files:
/etc/ssl/openssl.cnf changed [not included]

-- no debconf information