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fix(tcp): from_data reorders and re-pads TCP options - #1163
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_make_tcp_options dropped every NOP/EOOL it was given as "padding" and then padded each option to 4 octets on its own, inserting an EOOL after any misaligned option. A parsed segment therefore rebuilt with its NOPs moved, mid-list EOOLs, and a larger data offset (a0 -> b0 on http.pcap). Options are now emitted as given, and the list is padded once at the end: zero octets after a trailing EOOL, otherwise NOPs followed by an EOOL. test_tcp_udp_unit pinned the old drop-the-NOPs behaviour and is updated. Closes #1151
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- 4 new 1.5.0 entries: HTTP/2 sample stream identifiers (#1161), TCP option re-padding (#1163, breaking), format='pcap' output (#1164), declared lengths on truncated captures (#1166, breaking) - extend the PCAP Header (#1159), HIP (#1160) and from_data round-trip (#1162) entries rather than duplicating them - regenerate CHANGELOG.md with util/changelog_md.py - process.rst: entry-count pin re-measured, 189 -> 193 tests/project: conventions_doc_claims, changelog_md and documentation_claims pass; changelog_md.py --check is in step.
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make pylint,make mypy,make isort) — ran the tools ontcp.pyonly: mypy 0 errors, pylint no new messages (5 fewer); isort's complaint ontcp.py/test_tcp_udp_unit.pyis already onmainmake testpasses, and a test case covers the change — the 17tests/protocols/transport/test_tcp*/test_transport_unitmodules,test_option_roundtrip_unit, andtests/project, each run on its ownWhat is the purpose of your pull request?
fix— corrects a defectDescription of your pull request and other information
Closes #1151.
_make_tcp_optionsdropped the NOP/EOOL options it was given and padded each option to 4 octets separately. Now it emits options as given and pads once at the end: zero octets after a trailing EOOL, otherwise NOPs then an EOOL.Probe: parse each TCP segment,
TCP.from_data(info), compare header octets. The payload maker is stubbed so the HTTP rebuild (#1154) does not interfere.http.pcapbefore:a002…0402080a…01030306→b002…040201 00 080a…0100 030306 00.options-*.pcapregenerate byte-identical.New test file
tests/protocols/transport/test_tcp_options_roundtrip_unit.py: 4 passed with the fix, 4 failed without it.test_tcp_udp_unit.pypinned the old NOP-dropping behaviour and is updated.EXPECTED_FAILUREShad no TCP entries, so it is unchanged.