Round-7 blocker-1 residual: the PyYAML-absent line-parser fallback in
detect-platform.sh (_strip_scalar) returned a stringified scalar for
UNQUOTED YAML values that PyYAML's implicit resolver types as a
non-string (int/null/bool/float/timestamp). That bypassed _accept's
isinstance(str) guard and could surface a garbage credential (e.g.
"12345", "null", "true") where the PyYAML path resolves NO token and
fails closed -- violating the module invariant that the fallback is only
ever MORE conservative than PyYAML, never less.
Root cause fix: mirror PyYAML 6.0.3's SafeLoader implicit resolver. An
unquoted plain scalar matching the null/bool/int/float/timestamp forms
now returns None (fail closed); a quoted scalar is always a string and is
accepted verbatim (quote-stripped) as before. Quoted-string handling,
scope-aware attribution, indentation, and inline-comment stripping are
unchanged. The predicate was fuzzed against real PyYAML over ~800k random
tokens with zero fail-open divergences.
Extends the forced-PyYAML-absence parser-equivalence harness with
token: 12345/null/~/yes/true/3.14 (each fails closed identically to
PyYAML) and token: "12345"/'abc' (quoted literals still accepted).
Blockers 2/3/4 (port-bound host, origin+full-path URL pin, review-body
binding) are untouched.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Round-6 remediation for PR #866 addressing four cross-host exact-diff audit
blockers (REQUEST_CHANGES governs):
Blocker 1 (detect-platform.sh get_gitea_token_for_login line parser): the
PyYAML-absence fallback attributed any `key: value` at any depth to the current
login, so a token from a nested sub-map or a mis-indented line could be selected
where PyYAML fails closed, and inline comments were not stripped. The fallback is
now scope-aware — a field attaches only at the entry's own direct-field
indentation, only list items at the login list's own dash indent open an entry —
and _strip_scalar strips a trailing inline comment like PyYAML. It is therefore
only ever MORE conservative than PyYAML, never less.
Blocker 2 (detect-platform.sh host bind): credential binding compared
parsed.hostname only, dropping the port, so a :9443 login satisfied a portless
host and a matching :8443 login was rejected. Binding now normalizes scheme +
host + effective port (scheme default applied symmetrically) exactly like
gitea_url_matches_host.
Blocker 3 (issue-comment.sh + pr-review.sh read-back URL check): verification
used path.endswith, accepting a look-alike host or a decoy path prefix. It now
pins the returned issue_url/pull_request_url ORIGIN (scheme+host+effective-port)
and FULL path (deployment prefix + exact owner/repo + kind + number). A new
GITEA_WEB_BASE is exported from gitea_resolve_api_for_login for this.
Blocker 4 (pr-review.sh gitea_submit_review_verified): the submitted review body
was not verified, so a finalized/reused pending review id carrying foreign
Content passed. The persisted body is now bound to the exact submitted body.
Tests: added forced-PyYAML-absence parser-equivalence fixtures (nested sub-map,
sibling, mis-indent, inline comment, tab-indent fail-closed, port match/mismatch)
to test-gitea-login-resolution.sh; URL-forgery fail-closed cases
(wrong-host/owner/repo + prefix injection) to both write suites; and a
reused-review-id body-mismatch case to the pr-review suite.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
