This PR changes testssl.sh so that when ciphers are being listed in wide mode (i.e., using `neat_list()`) and the `--show-each` option is set, ciphers that are not available are printed in light grey, whereas ciphers that are available continue to be printed in black. This makes it easier to distinguish between ciphers that are available and those that are not (the "available/"not a/v" column remains).
This PR does not change the way that ciphers that are available are printed, but it includes a hook that would allow that to change. For example, for ciphers that are available, the name of the cipher suite could be printed in a different color depending on its quality (as is done for the "Negotiated cipher" in `run_server_preference()`). The same could be done for the "Encryption" and "Bits" columns.
- run_logjam(): determine dh bit size and based on this mark the common primes as more or less vulnerable
- run_logjam(): renamed remaining dhe variable to dh
- further house keeping in run_logjam()
In some cases, the "TLS extensions" line output for the "--server-defaults" option will not show `"encrypt-then-mac/#22"` even if the server supports this extension. The reason is that a server will only include this extension in the ServerHello message if it supports the extension and the selected cipher is a CBC cipher. So, if `determine_tls_extensions()` connects to the server with a non-CBC cipher, then it will not detect if the server supports the encrypt-then-mac extension.
It is possible that support for the extension will be detected by `get_server_certificate()`, but only if one of the calls to that function results in a CBC cipher being selected and OpenSSL 1.1.0 is being used (as prior versions did not support the encrypt-then-mac extension).
In this PR, if `determine_tls_extensions()` is called and `$TLS_EXTENSIONS` does not already contain `"encrypt-then-mac/#22"`, then an attempt will be made to connect to the server with only CBC ciphers specified in the ClientHello. If the connection is not successful (presumably because the server does not support any CBC ciphers), then a second connection attempt will be made with the "default" ciphers being specified in the ClientHello.
en.wikipedia.org is an example of a server that supports the encrypt-then-mac extension, but for which the support is not currently detected (unless OpenSSL 1.1.0 is used) since in the call to `determine_tls_extension()` a non-CBC cipher is selected.
This PR changes `read_dhbits_from_file()` so that, when the "quiet" parameter is absent, the selected curve is shown in addition to the number of bits. This PR only affects the output of `run_client_simulation()` and the `Negotiated cipher` in `run_server_preference()`.
David Cooper
Dirk Wetter