Modify TLS certificate decoding of validity timestamps to support tim…

[Fredamabob]

Modify TLS certificate decoding of validity timestamps to support times between 1950 and 2049, as per RFC 5280

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Link to redmine ticket: https://redmine.openinfosecfoundation.org/issues/3253

Describe changes:

• Modified the TLS cert validity timestamp parsing functions to return LONG_MIN on error instead of 0, to allow for timestamps at epoch 0 (1970). A previous version of that code also checked for any epoch value <=0, which meant that any valid timestamp between 1950 and 1969 (RFC5280) was rejected. The code got refactored since, but was still left with the edge case of epoch=0.
• Added a test case to verify that a ts between 1950 and epoch 0 is parsed correctly.
• Added a test case to verify that a ts at epoch 0 is parsed correctly

[codecov[bot]]

Codecov Report

Merging #5764 (e9d946f) into master (b66d013) will increase coverage by 0.00%. The diff coverage is 90.32%.

@@           Coverage Diff           @@
##           master    #5764   +/-   ##
=======================================
  Coverage   72.38%   72.39%           
=======================================
  Files         604      604           
  Lines      179362   179381   +19     
=======================================
+ Hits       129835   129855   +20     
+ Misses      49527    49526    -1     

Flag	Coverage Δ
suricata-verify	49.15% <47.36%> (+<0.01%)	:arrow_up:
unittests	63.08% <87.09%> (+<0.01%)	:arrow_up:

Flags with carried forward coverage won't be shown. Click here to find out more.

[catenacyber]

And maybe add a comment in the code referring to https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1

[suricata-qa]

Warning: no commits in this PR have specified the following ticket(s):

• 3253 - https://redmine.openinfosecfoundation.org/issues/3253

Please update the commit(s) and submit a new PR.

[catenacyber]

Friendly ping @Fredamabob are you planning to work on this again ?

[catenacyber]

Replaced by https://github.com/OISF/suricata/pull/8324