[JarryShaw]

• Searched for similar pull requests

• Followed the coding style (make pylint, make mypy, make isort) — the tools were run directly, not via make. They found nothing new: pylint E/W shows only the existing W0613/W0622, mypy reports 0 errors in the two files, isort is clean.

• make test passes, and a test case covers the change — only the modules listed below were run.

• Added a changelog entry — N/A, added centrally

• fix — corrects a defect

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Closes #1196. The HOPOPT and IPv6_Opts __option__ registries mapped only RPL_Option_0x63 to rpl. Type 0x23, the RFC 9008 code that the RPLOption schema already accepts, fell through to 'none'. This PR registers 0x23 in both registries and their docstring tables. The reader and maker already existed.

Probe HOPOPT(io.BytesIO(bytes.fromhex(h))) (same for IPv6_Opts):

• before: 3b002304… and 3b00230001020000 → AttributeError: 'RPLOption' object has no attribute 'data'
• after: 3b00230401020000 → RPLOption(type=0x23, id=2, rank=0); the zero-length 3b00230001020000 → ProtocolError: [OptNo 35] invalid format (same as 0x63)

Tests: the new tests/protocols/internet/test_rpl_option_unit.py gives 3 passed, 10 subtests. With the fix reverted it gives 6 failed (every 0x23 subtest), while the 0x63 controls pass. test_option_roundtrip_unit now generates RPL_Option_0x23 cases for both families, and they round-trip OK (6 passed, 362 subtests). No EXPECTED_FAILURES entry was involved. test_ipv6_ext_unit 30 passed, test_ipv6_extension_unit 61 passed, test_mpl_seed_rebuild_unit 4 passed, tests/project 389 passed / 1 skipped. run_unittest_leg.py protocols/internet: 498 tests, 0 failures, 0 errors.

[JarryShaw]

Cross-review verdict on c43925cd2: GOOD TO GO (Sonnet reviewed; the author ran on Opus).

• Root cause confirmed: _read_opt_rpl and _make_opt_rpl already existed, but only 0x63 was registered to them. On main, 0x23 raises AttributeError; on this branch it parses as RPLOption.
• 0x23 is the RFC 9008 code (act 00, chg 1). The reader decodes it as action 0 with change set, and the maker writes the 0x23 type octet back unchanged.
• Zero-length input: 3b00230001020000 now raises ProtocolError, the same as 0x63. Four octets is the fixed minimum.
• No other output changed: 22 captures (1579 frames) give byte-identical info digests on main and on this branch.
• Tests: the new tests fail without the fix (6 subtests). run_unittest_leg.py protocols/internet ran 498 tests with 0 failures.
• Pre-existing, filed as fix(ipv6-opts): RPL option drops reserved flag bits on rebuild and rejects RFC 6553 sub-TLVs #1199: reserved flag bits are dropped on rebuild (…0401… comes back as …0400…, which I re-ran), and options longer than 4 octets (RFC 6553 sub-TLVs) are rejected. Both behave the same on main for 0x63.

[github-actions]

Coverage: 88.90% (unit tier, Python 3.14, c43925cd2, Unit Tests run success)

Package	Statements	Missed	Branches	Partial	Cover
pcapkit (top level)	104	4	20	4	93.55%
pcapkit/const	18757	1034	2342	845	90.24%
pcapkit/corekit	1878	91	580	22	94.34%
pcapkit/dumpkit	142	0	42	0	100.00%
pcapkit/foundation	2442	102	852	39	94.38%
pcapkit/interface	112	7	40	5	92.11%
pcapkit/protocols	15759	190	4028	165	98.18%
pcapkit/toolkit	487	65	144	1	85.42%
pcapkit/utilities	429	4	122	4	98.55%
pcapkit/vendor	4409	2359	1006	158	42.84%

Per-file detail: the coverage-html artifact of this run.