transform: luaxform transform script

[jlucovsky]

Continuation of #12072

Add the luaxform transform that uses a Lua script to receive and transform a sticky buffer.

Lua transforms receive arguments

• (always): length of input buffer and input buffer
• (always): number of additional arguments (may be 0)
• (when present): argument array (bounded by argument count)

Arguments are passed to the Lua script as they appear in the rule:

 luaxform:./lua/lua-transform.lua, bytes 4, offset 13, hash sha256;

When the transform is invoked, 3 additional arguments are passed (arg count will be 3)

• bytes 4
• offset 13
• hash sha256

The Lua script is responsible for parsing and using the arguments and returning a tuple: output-buffer, output-buffer-byte-count

I used this Lua script:

function init (args)
  -- Optional, no return value
end

function transform(input_len, input, argc, args)
    SCLogNotice("Input length: " .. input_len .. " arg-count: " .. argc)
    for i = 1, argc do
        print("Argument " .. i .. ":", args[i])
    end
    return string.upper(input), input_len
end

return 0

Example rule using the Lua script:

alert http any any -> any any (msg:"Lua Xform example"; flow:established;  file.data; luaxform:./lua/lua-transform.lua; content: "abc"; sid: 1;)

Link to ticket: https://redmine.openinfosecfoundation.org/issues/2290

Describe changes:

• Luaxform transform changes

Updates

• Rebase following transform Rust conversions.

Provide values to any of the below to override the defaults.

• To use an LibHTP, Suricata-Verify or Suricata-Update pull request,
  link to the pull request in the respective _BRANCH variable.
• Leave unused overrides blank or remove.

SV_REPO=
SV_BRANCH=OISF/suricata-verify#2090
SU_REPO=
SU_BRANCH=
LIBHTP_REPO=
LIBHTP_BRANCH=

[codecov]

Codecov Report

Attention: Patch coverage is 52.59594% with 210 lines in your changes missing coverage. Please review.

Project coverage is 79.56%. Comparing base (278dc24) to head (b5ec5b3).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #12098      +/-   ##
==========================================
- Coverage   83.23%   79.56%   -3.68%     
==========================================
  Files         906      909       +3     
  Lines      257647   257683      +36     
==========================================
- Hits       214458   205014    -9444     
- Misses      43189    52669    +9480     

Flag	Coverage Δ
fuzzcorpus	61.17% <46.17%> (-0.04%)	⬇️
livemode	19.43% <12.99%> (+<0.01%)	⬆️
pcap	44.38% <30.16%> (-0.05%)	⬇️
suricata-verify	?
unittests	59.24% <26.41%> (-0.04%)	⬇️

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[suricata-qa]

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Pipeline 23291