TLS1.3 testing


Nothing important, but just wondering what’s the current status of TLS1.3 support.
So I downloaded openssl 1.1.1 from their git repo, compiled and installed.
[email protected]:~$ openssl version
OpenSSL 1.1.1-pre7-dev xx XXX xxxx

Still nothing:
[email protected]:~$ openssl s_client -tls1_3 -connect -crlf
140605700010432:error:1409442E:SSL routines:ssl3_read_bytes:tlsv1 alert protocol version:ssl/record/rec_layer_s3.c:1570:SSL alert number 70

no peer certificate available

No client certificate CA names sent

SSL handshake has read 7 bytes and written 244 bytes
Verification: OK

New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Protocol : TLSv1.3
Cipher : 0000
PSK identity: None
PSK identity hint: None
SRP username: None
Start Time: 1525828767
Timeout : 7200 (sec)
Verify return code: 0 (ok)
Extended master secret: no

Obviously this is total beta on both sides, so no complaints. Just wondering when people will think things will settle down and standardize now that they finalized the draft. Personally, I’m just looking forward to improved security, but IRL I know I’m probably going to be stuck with clients still using TLS1.0.


Indeed it’s a “total beta on both sides” which is a reason why you see such result.

As far as I can see, current master (as of today) of OpenSSL is on draft-26 ( On our side we use different version of the draft. So, the reason why TLS handshake fails is a mismatch in version of a draft implemented by both sides of the connection. This is why OpenSSL is reporting “alert number 70” (Unknown protocol).


I agree on the technical, but I just wondering when you think it will be finalized? Personally, I’m thinking this might take an another year. Just looking at the middle box issue, which I say was settled pretty quickly, but things pop up. I certainty don’t want to rush a RFC, and I think that may be happening. Just asking for opinions now, as I see a rush in security, but a lack in adoption obviously from the uncertainty of the protocol, which if it we want it work correctly will take time to implement and test correctly.


Obviously it’s hard to foresee what will happen in future and guess when all major players will implement, deploy and switch to TLS 1.3. A year sounds reasonable. I would be guessing that we will see this year quick adoption of TLS 1.3 driven by mobile devices and 0-RTT.


Chrome and Firefox both enable TLS 1.3 – draft, I think – for almost all users now. (Unless Firefox’s plan got delayed.)

Cloudflare sites probably get a pretty significant amount of TLS 1.3 traffic now.


According to from
Firefox, TLS 1.3 is supported:

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0)
Gecko/20100101 Firefox/60.0

Your user agent supports TLS 1.2, which is recommended protocol version
at the moment.
Experimental: Your user agent supports TLS 1.3.

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