Here is what I know.
When I connect to a brand-new Linux Web server with Chrome and click the "lock" icon, the key exchange algorithm is described as "ECDHE_RSA". (Yes I know what that is.)
When I connect with Internet Explorer 8 on Windows 7, the key exchange is described as "RSA with 2048 bit exchange". I know what that is, too.
With Firefox, it says I am secured by "AES-256, 256 bit keys". Which is (a) redundant and (b) tells me nothing about the key exchange algorithm.
When I run
openssl ciphers on my brand-new Linux machine, the output starts with:
(I suspect these are listed in order of OpenSSL's preference, but I do not know where this is documented.)
ECDHE stands for "elliptic curve Diffie-Hellman, ephemeral". That's great, but I want to know the actual key exchange algorithm, including the specific elliptic curve.
Here is what I really want: A big table, containing all possible pairs of SSL client and server (all versions), telling me what specific key exchange algorithm (including the actual elliptic curve) would be negotiated between them. Or enough information to construct that table.
I would settle for simply knowing how the latest versions of OpenSSL and CryptoAPI behave by default, and where this is documented.