Hi Janusz,

On Thu, Jan 03, 2019 at 11:49:35AM +0100, Janusz Dziemidowicz wrote:
> ??r., 2 sty 2019 o 19:04 Olivier Houchard <ohouch...@haproxy.com> napisa??(a):
> > You're right indeed. 0RTT was added with a development version of OpenSSL 
> > 1.1.1,
> > which had a default value for max early data of 16384, but it was changed to
> > 0 in the meanwhile.
> > Does the attached patch work for you ?
> This indeed results in following when using s_client:
>     Max Early Data: 16385
> However, I believe it still does not work. I was trying again to test
> it with s_client.
> Without allow-0rtt option I can resume TLS 1.3 session without problem:
> openssl s_client -connect host:port -sess_out sessfile
> openssl s_client -connect host:port -sess_in sessfile
> This results with:
> Reused, TLSv1.3, Cipher is TLS_CHACHA20_POLY1305_SHA256
> As soon as I add allow-0rtt (and your patch) above s_client results
> always with a new session:
> New, TLSv1.3, Cipher is TLS_CHACHA20_POLY1305_SHA256
> No matter what I do I was not able to resume any session with allow-0rtt 
> active.
> Just to rule out that I am using s_client in a wrong way I've made the
> same test against s_server. I was able to successfully resume session
> and even send early data that was accepted. So I believe that there is
> still something wrong in haproxy with TLS session handling.

Ah I think I figured it out.
OpenSSL added anti-replay protection when using early data, and it messes up
with the session handling.
With the updated attached patch, I get early data to work again. Is it better
for you ?


>From 82126322107bc628e32ff300195951fd660a43ac Mon Sep 17 00:00:00 2001
From: Olivier Houchard <ohouch...@haproxy.com>
Date: Wed, 2 Jan 2019 18:46:41 +0100
Subject: [PATCH] BUG/MEDIUM: ssl: Disable anti-replay protection and set max
 data with 0RTT.

When using early data, disable the OpenSSL anti-replay protection, and set
the max amount of early data we're ready to accept, based on the size of
buffers, or early data won't work with the released OpenSSL 1.1.1.

This should be backported to 1.8.
 src/ssl_sock.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 282b85dd..13ce2e5b 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -3869,6 +3869,10 @@ ssl_sock_initial_ctx(struct bind_conf *bind_conf)
        SSL_CTX_set_select_certificate_cb(ctx, ssl_sock_switchctx_cbk);
        SSL_CTX_set_tlsext_servername_callback(ctx, ssl_sock_switchctx_err_cbk);
 #elif (OPENSSL_VERSION_NUMBER >= 0x10101000L)
+       if (bind_conf->ssl_conf.early_data) {
+               SSL_CTX_set_options(ctx, SSL_OP_NO_ANTI_REPLAY);
+               SSL_CTX_set_max_early_data(ctx, global.tune.bufsize - 
+       }
        SSL_CTX_set_client_hello_cb(ctx, ssl_sock_switchctx_cbk, NULL);
        SSL_CTX_set_tlsext_servername_callback(ctx, ssl_sock_switchctx_err_cbk);

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