I want to capture a sample SSL traffic with wireshark, which it's version is TLS1.3(newest version). I enabled the TLS 1.3(draft23) flag in chrome browser, and also update my wireshark to version 2.6.2.
then I start to open some sites like https://gmail.com and https://www.thesslstore.com which supports this version and capture the traffic.
but when I open the captured traffic, the version of SSL header is TLS1.0 or TLS1.3 while in the section of the protocol in the top of window, TLSv1.3 is showed.
There are routers, gateways, etc. that look at this header. Because TLS 1.3 is somewhat new, you will often see older TLS versions specified. I most often see TLS 1.2, but my code talks to AWS - that may be their standard.
Related
I'm using sim800 module to connect to a server using TLS. Due to a security policy in our company, the module must not continue the connection establishment if the remote host tries to use and older version of SSL/TLS.
Is there a command or setting in sim800 that can be used to choose the TLS/SSL version when connecting to a server?
*I have searched its SSL and AT command manuals and couldn't find anything useful.
There's a TLS firmware of sim800 and you can upgrade to it, this firmware use TLS version 1.2 but you can't select the version of TLS,infact sim800 use latest version of TLS that firmware supported.
TLS Firmware version
1418B09SIM800C24_TLS
I have a Ubuntu 16.04 Server and I would like to know witch version of TLS is already installed on my server.
And how to upgrade to version 1.3 if version version is under v1.3
Thank you
While you don't specify it you are probably asking about the TLS support in your web and/or mail server. For the common servers on Linux the support is implemented with OpenSSL. Since you are using Ubuntu 16.04 you by default have OpenSSL version 1.0.2 which supports TLS up to TLS 1.2. But note that configuration of the servers might cause the actual protocol support to be limited.
There is no official TLS 1.3 yet, i.e. the protocol is still not finalized. Support for TLS 1.3 is expected to be available in OpenSSL 1.1.1 which is still in development.
Sniffing the packets with some application like Wireshark would reveal the information; the protocol version used in a connection is in the ServerHello message or
use http://ssl-checker.online-domain-tools.com tool to verify
I would suggest that you use the SSL test website by Qualys. If you ran your webserver with SSLProtocol +All for just a quick test, it would tell you what SSLProtocols are being served with your pages and a recommendation on which ones should and should not be used.
On a side note, I made a recurring task to test my sites; I found something even today that had changed since I last checked 3 months ago.
https://www.ssllabs.com/ssltest/index.html
Out of curiosity, can someone help explain to me what will theoretically happen if a uri of protocol https (TLS 1.1) is accessed on a primitive browser that predates TLS 1.1? E.g. a primitive feature phone with GPRS connectivity.
If your server only support TLS1.1 and a browser without TLS1.1 try to connect, the connection will fail.
Usually servers supports TLS1.0, 1.1 and 1.2 : Modern browsers can use the 1.2 version, but older ones can still connect on the 1.0 version.
https://ssllabs.com can help you see it (it tests websites to determine which browser can connect to it and the level of security of the connexion)
We have clients who can be using anything, WindowsXP,Vista,Linux....
Currently our systems support SSLV2 and SSLV3.But, we are planning to disable both SSLV2 and SSLV3 in windows server 2008R2 in favour of TLS 1.2.
Will it have any breaking changes with the end user?I'm worried that If I disable SSLV3 ( and SSLV2) , some of the clients who use windowsXP(for example) might not be able to access my web service.
PS: Tried to find a similar question in stackoverflow, didn't find any. So, posting this as a question. :)
This is one of the scenarios where you will NOT be able to support old clients using insecure protocols and expect to have decent security.
If you have not enabled TLS 1.2 yet, do so.
Some clients do not support TLS 1.2 (e.g., older Android versions). You may need to support TLS 1.0 and 1.1 in addition to 1.2. While not ideal, it is definitely better than supporting SSL 2.0 and 3.0.
Post an announcement indicating that your web service is being upgraded to meet minimum security requirements and set a date for retiring insecure protocols.
Optionally, check your server metrics to see what protocols/ ciphers are used. Since you haven't mentioned your web server, I'm assuming it is IIS, in which case this is not easy[1][2].
Retire SSL 2.0 and SSL 3.0. There will be a few clients who will not be able to connect. Plan to have an answer ready for them. If you have clients running XP and using IE6, they have bigger issues than not being able to access your web service.
While you are at it, run your TLS configuration through an online
scanner like SSL Labs to ensure you fix any other issues.
I would like to display a message to customers who's browser's highest level of encryption is SSLv3. Is it possible for me to target browser settings of SSLv3 and lower? Client or Server code? We will be allowing lower versions of SSL to use our site during a certain grace period. During this grace period, we would like to display a message only to those users that have browser settings of SSL3 or lower.
Not easily. The browser's supported SSL versions are not detectable until the SSL handshake is in progress, and even then only if the browser uses an SSLv2 handshake to allow dynamic version negotiation. If an unsupported version were detected, you would not be able to send a message back since the handshake failed and the connection would be closed before you could send any message. However, SSL itself has an error packet that gets sent during handshaking, and it can specify a version mismatch error.
The best you can do in your own code is support all SSL versions on the server side, let the client complete a handshake normally, and then detect which version was actually used and send back a message if the SSL version is too low.
Or, you could simply enable TLSv1 or higher only, and simply refuse to let older clients connect at all. They just would not get a nice error message unless the browser decided to detect the SSL version mismatch error and display its own pretty message about it.
Firstly, nowadays, you can generally forget about clients that don't support at least SSLv3. SSLv3 has been widely available for many years.
The TLS Client Hello message, sent when the connection is initiated by the browser, should contain the highest TLS version it supports:
client_version
The version of the TLS protocol by which the client wishes to
communicate during this session. This SHOULD be the latest
(highest valued) version supported by the client. For this
version of the specification, the version will be 3.3 (see
Appendix E for details about backward compatibility).
Appendix E is of course worth looking at.
(The Client Hello message will also contain the list of cipher suites the client supports, which is possibly relevant for the general idea of your question.)
Of course, this specification is just a "SHOULD", so a client supporting TLS 1.2 could still send a Client Hello for TLS 1.1, but what would be the point? By doing so it would have no chance ever to use TLS 1.2 anyway. It could be a preference box that is turned off, but that would effectively make it a client that doesn't support the highest version anyway. (If you want anything more subtle, you'd need to build a database of known user agents, which will be partly unreliable, and for which you'd need to analyse the full user agent string to know everything possible about the platform.)
Now, how to convey the content of the Client Hello message to your application is another matter, and depends very much on which SSL/TLS stack you use. It might not even be directly possible without modifying that SSL/TLS library or the server you're using.
This being said, you can generally get the negotiated TLS version during the current session quite easily. Since that version is the "lower of that suggested by the client in the client hello and the highest supported by the server" (i.e. "min(max(client), max(server))"). If your server supports SSLv3, TLS 1.0, TLS 1.1 and TLS 1.2, and since the latest version is TLS 1.2 anyway, what you'll get during your current connection will also be the max currently supported by the client. As long as your server supports the latest version, you should be able to know what the client supports at best from any live connection.
If you're behind Apache HTTP server's mod_ssl, you should be able to get that from the SSL_PROTOCOL environment variable. You should also be able to get the protocol from the SSLSession in Java.
(If you are willing to write a more bespoke service, you could pass further details like the cipher suites more directly to your application, like this service from Qualys SSL Labs does, although I'm not sure if it's meant to be widely available or just a test service.)
I'd have to agree with Remy about it being a bit challenging.
However, a good starting point may be to retrieve some SSL (certificate) information.
Something similar to this:
X509Certificate certChain[] =
(X509Certificate[]) req.getAttribute("javax.net.ssl.peer_certificates");
Another way of getting more information is to retrieve the cipher_suite attribute (similar to the code snippet above).
javax.net.ssl.cipher_suite
I hope this (at least) gets you closer.
Good luck.