ECDHE not working when server hello, certificate, server key exchange are encapsulated in single record layer about scapy-ssl_tls

[alexmgr]

Hi @perrin-ay,

Thanks for taking the time to write the detailed bug report.
Stacked handshakes are super painful to deal with, and I thought we addressed that for good a while back with #13 ;).
I have an idea why this is happening, but I don't have time to address this right now. Fixing insert in ssl_tls_crypto to iterate on handshakes instead of records should do the trick. I'll pick this up when i have a bit of time.

Thanks again!

[perrin-ay]

Sounds great. Thank you much!

[alexmgr]

Hi @perrin-ay,

I have had to fix this in order to get TLS 1.3 to dissect properly. Could you chekout the tls1.3 branch and try it out?

I have had to slightly change the interface of the TLSHandshake layer to make this generic enough, so you'll need to slightly adapt your script. For example, a client hello now becomes:

TLSRecord(version=tls_version) / TLSHandshakes(handshakes=[TLSHandshake() /
        TLSClientHello(version=tls_version, cipher_suites=[TLSCipherSuite.ECDHE_RSA_WITH_AES_128_GCM_SHA256, ])])

You can also now create stacked handshakes, ala java, but more importantly dissection works properly in all cases.

Would you mind giving this a try and letting me know if this fixes your problem?

Thanks

[perrin-ay]

Hey @alexmgr ,

This fixed the problem. Thanks again for looking into this ! cheers

[alexmgr]

Thanks for verifying!