3 Commits

Author	SHA1	Message	Date
Tom Boucher	9e4f0e99ad	fix(#3631): exclude only __pycache__-resident bytecode from the consent digest (#3650) ... * test(3631): failing-first coverage for bytecode-cache in the consent hash bundleContentHash digests a walk with no exclusion, so a routine 'python3 -m unittest' inside a Python-backed capability bundle writes __pycache__ under the bundle, the recomputed hash stops matching the consent record, and the capability silently goes inactive — no error, no warning, and loop render-hooks then omits its step and gate. Two distinct triggers, and the second is the sharper one: collectBundleEntries pushes a {kind:'dir'} entry for EVERY directory and the digest emits a TAG_DIR marker for it, so an EMPTY __pycache__/ flips the hash before a single .pyc is written. A fix filtering only *.pyc would leave that live. Verified by execution against the built lib: 5 of 7 probe rows diverge from intent today, including the empty-directory row. The anti-regression rows are the point of the shape: editing a real scripts/m.py and adding node_modules/pkg/index.js must BOTH still change the hash. node_modules is deliberately not excludable — its contents are required at runtime, so dropping it from the digest would stop consent binding executable content. The symlink row pins ordering: exclusion must apply after the lstat fail-closed rejection, never before. Refs #3631 * fix(3631): exclude derived bytecode caches from the consent digest RED proven at e5ba8f1fe on the remote runner: 8 failures, exactly the rows predicted to fail, with the four anti-regression rows already green. collectBundleEntries now skips a hardcoded, gitignore-independent set from the DIGEST: basenames __pycache__, .pytest_cache, .DS_Store, and any .pyc/.pyo file. Matching is byte-exact on the raw Buffer name (the walk never utf8-decodes) and case-sensitive, so the digest does not vary with how a name happens to be spelled on a case-insensitive volume. Three properties were preserved deliberately, each pinned by a test: - The filter runs AFTER the lstat symlink/non-regular fail-closed rejection. Filtering first would have turned the exclusion into a way to smuggle a symlink past the check; a symlink named x.pyc still throws. - Excluded entries still count toward BUNDLE_MAX_FILES and BUNDLE_MAX_TOTAL_BYTES. The caps guard the WALK; the digest answers a different question, and exclusion must not become an unbounded-bytes hole. - An excluded DIRECTORY is neither emitted as a TAG_DIR marker nor recursed into. The directory marker was the sharper half of this bug: an empty __pycache__ flipped the hash before any .pyc existed, so a *.pyc-only filter would have left it live. The issue proposed either a gitignore-aware walk or a list including node_modules. Both are rejected. A consent binding must not delegate its scope to a .gitignore the bundle author does not control — one line there would drop arbitrary executable content out of the hash. And node_modules holds code that is required at runtime; excluding it would stop consent binding executable content, turning a usability bug into a supply-chain hole. What makes __pycache__ different is that CPython validates each .pyc against its sibling source, which remains hashed, so a real code change still invalidates consent. Docs: CONTEXT.md's 'EVERY regular file AND directory' claim is corrected in place. ADR-2363's residual-gap section said the walk had 'no exclusions' — per docs/adr/README.md ('ADRs are append-only') that is corrected by a dated amendment rather than an in-place edit. Its D4 argument is unaffected: skill bodies are .md and stay bound. Fixes #3631 * fix(3631): narrow the digest exclusion after two isolated security reviews The first cut of this fix passed the full suite and was still wrong. Both orthogonal reviews rejected it, and the second one found a hole that has nothing to do with Python. HIGH — an excluded DIRECTORY was 'continue'd before recursion, so its whole subtree was permanently outside the digest. Declared hook script paths allow '_', '.' and '/' with no directory or extension rule, so hooks:[{script:'__pycache__/run.js'}] installed, executed via node, and its bytes could be rewritten forever without moving the hash. Ship benign v1, collect consent, then own the machine. No Python involved. FALSE RATIONALE — the justification I wrote into the code, CONTEXT.md, the ADR amendment and the changeset claimed CPython validates a cached .pyc against its sibling source, so the source staying hashed kept consent honest. That is not true, and I proved it by execution rather than argument: default timestamp invalidation compares only the source's mtime and size, both settable by anyone who can write the bundle. A forged pyc ran while the .py was byte-identical. Also wrong: '*.pyc' matched anywhere, but a legacy sourceless scripts/x.pyc IS importable, so excluding it was a live vector. Narrowed to what is actually defensible: - a DIRECTORY named __pycache__/.pytest_cache has only its TAG_DIR marker suppressed; the walk still recurses and hashes every non-excluded child. - .pyc/.pyo are excluded ONLY when the parent basename is exactly __pycache__. - a regular FILE named __pycache__, and a DIRECTORY named x.pyc, stay bound. - declared hook paths containing a __pycache__/.pytest_cache segment or a .pyc/.pyo basename are now rejected in both validator copies — a file named .pyc can contain perfectly valid JavaScript, so the exclusion must not be reachable from a declared surface. Accepted residual risk, stated plainly in ADR-2363 and CONTEXT.md instead of explained away: a forged __pycache__/mod.pyc matching an unmodified, still-hashed mod.py executes without moving the digest. Before this change that write was detected. It is accepted to stop routine bytecode caching from silently deactivating capabilities, and it is bounded — the attacker needs post-consent write access, everything outside __pycache__/*.pyc stays hashed, and no declared surface can point into the excluded space. Known limitation, not papered over: .pytest_cache CONTENTS still move the digest. Only the directory marker is suppressed. Excluding that subtree would reopen the HIGH finding. Refs #3631 * fix(3631): drop the .DS_Store exclusion and pin what the caps actually bind Second round of isolated review findings. The hardening closed the two original holes — both re-reviews confirmed that by execution — but it introduced a new one of the same shape, and left three claims unbacked. HIGH, self-inflicted: .DS_Store was excluded from the digest at any depth, but the hook path validator was hardened only for __pycache__/.pytest_cache/.pyc/.pyo. So script:'hooks/.DS_Store' was ACCEPTED, runnableHookCommand emits the bare quoted path for a non-.js name (the branch .sh hooks already use), and capability-source copies it with its mode bit intact. Ship it +x with a benign shebang, take consent, then rewrite it forever — the digest never moves. Fixed by DELETING the .DS_Store exclusion rather than teaching the validator about it: .DS_Store has nothing to do with this issue's Python bytecode symptom, and an excluded filename is a permanently unhashed name. The narrower the exclusion, the smaller the hole. The residual-risk bound in ADR-2363 and CONTEXT.md claimed declared surfaces cannot reach excluded space. That is false and is now stated correctly: node resolves an unregistered extension through the default .js handler, so a hashed, consent-covered hooks/run.js that requires '../__pycache__/mod.pyc' reaches it in one hop. The validator guard raises the bar for DECLARED surfaces; it does not contain the risk. The two bounds that are real — post-consent write access required, everything outside __pycache__/*.pyc still hashed — are kept. The BUNDLE_MAX_FILES boundary test had gone vacuous: it padded with root-level *.pyc, which the hardening made non-excluded, so it no longer proved anything about excluded entries while the ADR claimed the caps were test-pinned. It now pads __pycache__/f{i}.pyc, with the arithmetic re-derived by execution (capability.json + the still-counted __pycache__ dir + N). BUNDLE_MAX_TOTAL_BYTES had zero coverage at all and is now pinned by a sparse 32 MiB __pycache__/big.pyc that must still trip the size cap — the test that proves exclusion did not become an unbounded-bytes hole. Added the parity assertion CLAUDE.md's Generative Fix Divergence rule requires for the two isSafeHookScriptPath copies, and proved it can fail: mutating one BUILT copy to drop .pyo made the parity check report the divergence. Also pinned semantics that were correct but untested and would have survived mutation — __pycache__/sub/x.pyc stays hashed (the parent resets to sub, which is the recursion threading itself), .pytest_cache/y.pyc stays hashed, and .pyo in both directions, which was a free surviving mutant. Changeset rewritten: it still described the rejected wholesale-exclusion semantics. Refs #3631 * chore(3631): backfill changeset PR number (#3650) --------- Co-authored-by: sim <sim@local>	2026-08-18 22:35:54 -04:00
Tom Boucher	3fac6e629f	test(#3145): bound the installer/runtime cluster onto the process seam (#3176) ... * test(#3145): bound the installer/runtime cluster onto the process seam Migrates 156 unbounded sync spawn sites across 47 files. Allowlist 120 to 73. Timeouts are sized from evidence already in the tree rather than a house default, because this wave spawns installers rather than git plumbing and an undersized bound does not catch a hang -- it manufactures CI flake, which is worse, since a flake gets re-run instead of investigated. install.test.cjs records a real spawnSync ETIMEDOUT at a 60000ms cap on a loaded bench while another lane passed the same commit in 12.7s, so full installs are bound at 120000ms against that recorded incident. Also adds an auditable escape to the guard's timeout ceiling. The 600000ms cap was set in #3143 from partial evidence, but fragment-single-edit- propagation carries a documented, load-tested 900000ms bound on a run that chains a full build plus eight generators -- the guard would have rejected a correct timeout the moment that file left the allowlist. A value above the ceiling is now permitted only with an inline allow-spawn-timeout-ceiling marker carrying a non-empty reason. It raises the ceiling; it never waives the requirement for a bound, which is asserted directly. install-shared.cjs keeps its hand-rolled assert rather than routing through throwIfFailed: its message embeds both streams, and throwIfFailed carries only a trimmed stderr. The message now also names the outcome, so a bounded timeout reads as such across its 38 importers instead of as expected null to equal 0. * test(#3145): extract class-norm timeouts and correct the build-hooks sizing A pre-PR review found 52 copies of four class-norm timeout constants across this wave. These are not per-suite fixture bindings -- they are shared facts about how long a class of subprocess takes, derived from a recorded bench incident. That norm already moved once (60000 to 120000 after a real ETIMEDOUT), and 52 copies would have drifted the next time it moved. Extracts tests/helpers/timeouts.cjs, where each norm is justified once, and converts the copies. A site that genuinely differs -- a real tsc compile, or regen:derived -- keeps its own local constant with its own justification. Also corrects a misclassification: scripts/build-hooks.js was sized as a build at 120000 in twelve places and 60000 in another, but it compiles and bundles nothing. Its own header says no bundling needed; it copies pre-built files and syntax-checks them with vm. Three different values bounded one script; now there is one. * test(#3145): fix red CI — lint self-match and a Windows chunk overrun Two failures on PR 3176. lint-allow-test-rule-refs read a RuleTester fixture as a real exemption. The fixture exists to prove an unrelated marker does NOT suppress the rule, so it carries that marker's literal text as test data. Split via concatenation, the same idiom no-unbounded-spawn-allowlist.test.cjs already uses for its own self-match problem. The explanatory comment needed the same treatment. The Windows shard 3/3 chunk was killed at its 600000ms budget. Output stopped seven minutes before the kill, so this was an overrun rather than a slow chunk: regenDerivedPropagatesSingleFragmentEditWithNoSecondSourceSurface runs regen:derived bounded at 900000ms, which is larger than the whole chunk budget, so the chunk killer always fires first and it can never complete there. Both the test and that bound predate this change; modifying the file pulled it into the Windows targeted set and exposed it. Skipped on Windows with the reason recorded; the Linux lanes cover it. The 900000 bound and its ceiling marker are unchanged -- they are correct. * test(#3145): refresh the stale test-timings cost table The Windows shard was killed at its 600000ms per-chunk budget. run-tests.cjs packs chunks by measured duration from tests/test-timings.json, and an unknown file falls back to the table's median weight -- advisory by design, but it silently underweights exactly the files that matter. Four of the failing chunk's 22 files were absent from the table, including the two heaviest: fragment-single-edit-propagation.install.test.cjs at 230s (it runs regen:derived) and agent-fragments-emission.install.test.cjs at 79s. Both were weighted as average, so the chunk's total weight read 53.68 against a budget of 60 and the packer produced a single chunk. Regenerated from a passing full-suite run, per the remedy the script itself documents. 700 to 770 entries, 70 added, 0 dropped -- verified, since gen-test-timings.cjs replaces the table wholesale rather than merging. Proven against the real packer: the same 22 files now weigh 103.91 and split into two chunks. No logic, budget, or timeout was changed; raising a budget to make a red gate pass is not a fix. --------- Co-authored-by: sim <sim@local>	2026-08-07 15:18:18 -04:00
Tom Boucher	e7855bc217	fix(#1459): user-owned consent store gates third-party capability activation; env/cwd in disclosure; loader validator parity (#1473)	2026-06-20 01:59:03 -04:00