xxd is not a strict requirement and a fallback logic exists to handle its absence. However it is in general more performant and helpful in debugging as well which is desirable in many situations like ci/cd pipelines. See commit 3756cdc for details
This commit makes some minor improvements to code that converts ASCII-HEX to binary.
First, testssl.sh currently has two functions that do the same thing: asciihex_to_binary() and hex2ascii(). This commit all calls to either of these functions with calls to hex2binary(), which is based on the current asciihex_to_binary().
This commit also changes direct use of printf to calls to hex2ascii() in generate-ccm-counter-blocks(), ccm-compute-tag(), and generate_gcm_counter().
Finally, this commit cleans up the implemention of hex2binary() a bit and introduces the option to use xxd, if that program is available. Using xxd rather than multiple calls to printf has a couple of advantages. xxd is a bit faster. However, the primary advantage is that when debugging (i.e., using bash -x), each call to hex2binary() only includes a few steps, regardless of how long the string is, whereas using printf the call to hex2binary() could take hundreds of steps.
Modify sclient_auth() to use checks similar to sclient_connect_successful() to determine whether the connection attempt was successful. Replace uses of awk and grep with Bash internals string comparisons.
This commit is a first step towards addressing #1709. It attempts to determime whether certificate-based client authentication is (1) not requested, (2) optional, or (3) required. If it is either optional or required, then it extracts the list of CA names (DNs) that the server sends in its CertificateRequest message.
The code for extracting the CA list from the CertificateRequest message seems to be working correctly. However, this commit is incomplete for a couple of reasons. First, it does not produce any new output, it just collects the information. Second, sclient_auth() needs some work.
The current sclient_auth() simply returns 0 if $OPENSSL returned 0. This may be okay if only trying to determine whether certificate-based client authentication is required. However, if it is optional, then the output will include "CertificateRequest", but $OPENSSL will return 0, since the connection was successful even though the client did not provide a certificates.
If $OPENSSL does not return 0, then sclient_auth() checks whether Master-Key is present. This works for TLS 1.2 and earlier, but not for TLS 1.3. So, sclient_auth() needs to be updated to work correctly with TLS 1.3.
The modified version of sclient_auth() will set CLIENT_AUTH and CLIENT_AUTH_CA_LIST for any version of TLS, but the remaining part of the code needs work. As I am not clear on the reason for this code, I need some help with it. Why does the code only look for "CertificateRequest" if "Master-Key" is present? Why is there a check for Session-ID in a function that is supposed to just be checking for client authentication. Why is CLIENT_AUTH set to false if SESSION-ID is absent (this is a no-op since CLIENT_AUTH would already have been false)?
See #1148 and #1805.
As noted in #1148, testssl.sh is not current designed to handle a mass testing file in which CSV, HTML, LOG, and/or JSON file names are provided in the mass testing file. If a child process receives a command line with one of the files, it assumes the same command-line option was provided to the parent so that the output of every test is being written to this one file. If this assumption is wrong, then either the file will not be created at all or it will be malformed since it will be missing header and/or footer information.
This PR partially addresses the problem by introducing new command-line arguments that are for internal use only. These command line arguments allow a child process to distinguish between a CSV, HTML, LOG, or JSON file that it is supposed to create itself versus one that is to be shared by all of the child processes.
There is one major limitation to this PR. The code for handle command-line arguments in the mass testing file is very simple and cannot handle whitespace characters, whether they are enclosed in quotes or are escaped. So, any file names included in the mass testing file cannot have whitespace characters.
