I am trying to enable TLS 1.2 in my web app which uses Tomcat 5.5 and Java 1.7. I am checking the website TLS version on both chrome and IE. Things I have tried:
adding -Dhttp.protocols = TLSv1.2 to JAVA_OPTS in setenv.bat. (still shows TLS 1)
setting ssLENabledProtocols to TLSV1.2 in the server.conf file. (still shows TLS 1)
setting ssLProtocol to TLSV1.2 in server conf file. (website does not open)
setting JAVA_HOME to JDK 8 in setenv.bat file. (still shows TLS 1)
Is there anything I could do to enable TLS 1.2?
There is a website hosted using IIS with TLSV1.2 on the same server.
I'm reversing an Android application and I noticed, while sniffing, that something weird happens.
TLSv1.3 introduces few new ciphers such as
TLS_AES_256_GCM_SHA384
TLS_CHACHA20_POLY1305_SHA256
TLS_AES_128_GCM_SHA256
TLS_AES_128_CCM_8_SHA256
TLS_AES_128_CCM_SHA256
And, from what I've read on OpenSSL documentation (https://wiki.openssl.org/index.php/TLS1.3),
There are new ciphersuites that only work in TLSv1.3. The old ciphersuites cannot be used for TLSv1.3 connections and the new ones cannot be used in TLSv1.2 and below.
Now, this application does something very strange: .
It is using TLSv1.2 with new TLSv1.3 ciphers during "Client Hello" and server, which also supports TLSv1.3, allows it and they start the communication for some reason.
How is that possible? Thank you.
No, you are missing an important new aspect I think ( I can not see your linked image, you should post all relevant data inside the question itself).
For compatibility reasons, TLSv1.3 try to mask itself as TLSv1.2 during ClientHello, see https://www.rfc-editor.org/rfc/rfc8446#section-4.1.2 :
4.1.2. Client Hello
When a client first connects to a server, it is REQUIRED to send the
ClientHello as its first TLS message.
Structure of this message:
uint16 ProtocolVersion;
opaque Random[32];
uint8 CipherSuite[2]; /* Cryptographic suite selector */
struct {
ProtocolVersion legacy_version = 0x0303; /* TLS v1.2 */
Random random;
opaque legacy_session_id<0..32>;
CipherSuite cipher_suites<2..2^16-2>;
opaque legacy_compression_methods<1..2^8-1>;
Extension extensions<8..2^16-1>;
} ClientHello;
Note the legacy_version being TLSv1.2 in fact, and then the explanation:
legacy_version: In previous versions of TLS, this field was used for
version negotiation and represented the highest version number
supported by the client. Experience has shown that many servers
do not properly implement version negotiation, leading to "version
intolerance" in which the server rejects an otherwise acceptable
ClientHello with a version number higher than it supports. In
TLS 1.3, the client indicates its version preferences in the
"supported_versions" extension (Section 4.2.1) and the
legacy_version field MUST be set to 0x0303, which is the version
number for TLS 1.2. TLS 1.3 ClientHellos are identified as having
a legacy_version of 0x0303 and a supported_versions extension
present with 0x0304 as the highest version indicated therein.
(See Appendix D for details about backward compatibility.)
As for cipher suites and TLS versions, the situation is more complicated. TLSv1.3 standardized only a few of them as mandatory, for reasons explained in the specification.
However that does not strictly forbid other TLS versions to use them either.
See:
ChaCha20-Poly1305 Cipher Suites for Transport Layer Security (TLS): This document describes the use of the ChaCha stream cipher and
Poly1305 authenticator in version 1.2 or later of the Transport Layer
Security (TLS) protocol
TLS 1.2 Update for Long-term Support with AES+SHA
The "AES GCM" family was defined 10 years ago in https://www.rfc-editor.org/rfc/rfc5116
TLSv1.3 standardized on only perfect forward privacy so that meant only (EC)DHE key exchanges, if not using PSK (see section 2 of RFC8446)
Have a look at https://security.stackexchange.com/a/77018/137710 and https://github.com/ssllabs/research/wiki/SSL-and-TLS-Deployment-Best-Practices#23-use-secure-cipher-suites
But the TLSv1.3 ciphers suite is defined differently, using new names, because previous ones were not relevant anymore, as TLS 1.3 made some choices about algorithms to use, etc. that removes volatility in some parts.
Hence you will see this warning in OpenSSL changelog:
Separated TLSv1.3 ciphersuite configuration out from TLSv1.2 ciphersuite
configuration. TLSv1.3 ciphersuites are not compatible with TLSv1.2 and
below. Similarly TLSv1.2 ciphersuites are not compatible with TLSv1.3.
In order to avoid issues where legacy TLSv1.2 ciphersuite configuration
would otherwise inadvertently disable all TLSv1.3 ciphersuites the
configuration has been separated out. See the ciphers man page or the
SSL_CTX_set_ciphersuites() man page for more information.
(https://github.com/openssl/openssl/pull/5392)
CloudFlare documentation on https://support.cloudflare.com/hc/en-us/articles/200933580-What-cipher-suites-does-CloudFlare-use-for-SSL- says below table:
Although TLS 1.3 uses the same cipher suite space as previous versions of TLS, TLS 1.3 cipher suites are defined differently, only specifying the symmetric ciphers, and cannot be used for TLS 1.2. Similarly, TLS 1.2 and lower cipher suites cannot be used with TLS 1.3 (IETF TLS 1.3 draft 21).
When using a VPN-like connection between the two servers (not web servers or anything like it), besides authentication I would like to enable encryption.
The authentication portion is already working, wanted some help at the encryption level.
I know that TLSv1.2 and v1.1 is supported alongside wih SSLv3.
I would only like to use TLSv1.2 and nothing else.
TLSv1.2:!aNULL:!eNULL
Is the the correct cipher suite to use?
Information from https://www.openssl.org/docs/manmaster/apps/ciphers.html seems not to be very helpful...
Can anyone help this this matter?
I would only like to use TLSv1.2 and nothing else.
If you want to use TLS 1.2 only you have to configure the protocol and not the ciphers. Limiting the ciphers to only TLS 1.2 ciphers drops support for all ciphers which are available since SSL 3.0 and which are still supported by TLS 1.2. Depending on the peer you might end up with no shared ciphers this way.
If you still want to restrict the ciphers you might try the string TLSv1.2:!aNULL:!eNULL. This will make it only use ciphers newly introduced in TLS 1.2 and thus implicitly enforce the protocol. But again, it is no guarantee that the server supports these ciphers even if the server can do the TLS 1.2 protocol.
I am trying to troubleshoot an issue where connection is reset.
When i captured the TCP packets in wireshark, I see that Version is shown as SSL2.0 and then after Handshake Message Type, it shows TLS 1.2.
Actually my server only accepts TLS 1.2.
Please help me to understand if client initiated SSL v2.0 or TLS 1.2?
SSLv2 Record Layer: Client Hello
[Version: SSL 2.0 (0x0002)]
Length: 257
Handshake Message Type: Client Hello (1)
Version: TLS 1.2 (0x0303)
Cipher Spec Length: 216
Session ID Length: 0
Challenge Length: 32
Cipher Specs (72 specs)
Challenge
We need to support 2 way SSL in our project . For this, we need to create the TLS v1.2 certificates. I am not sure how to mention the TLS version (i.e 1.2) while creating the certificate.
The certificate is independent from the TLS version. The TLS version (and ciphers) are relevant for the SSL handshake which includes the exchange of the certificate(s). The validation of the certificates is outside the SSL handshake and is thus independent from TLS version and ciphers but depends only on the certificate itself. There is a small dependency that with TLS 1.2 the acceptable signature algorithms can be send, but as long as the certificate is signed with SHA-256 (current state of the art) you are safe.
Certificates are based on x509 standard which has certificate version(Currently v3). Like Steffen explained above independent from SSL/TLS versions.