audit-runtime-semantics

Phase Path Containment Preflight

Before any phase artifact read, write, directory creation, command, or handoff, run this preflight completely and block on any failure:

1. Read .open-xquant/workspace.yaml. Resolve version_root from paths.versions_dir, using versions only when that key is absent. Require version_root to be a safe workspace-relative path: reject an absolute path or any .. path segment, resolve it canonically with symlinks, and require the result to stay inside the workspace.
2. Read current.json. For normal phase work, set expected_version_id to current.json.active_version; it must exist. Only a contract that explicitly owns cross-version inspection may instead set expected_version_id from the referenced version id for that historical read. This exception never permits active-version work to consume another version.
3. Set the intended version directory to <version_root>/<expected_version_id>/ and resolve it canonically. Require the intended version directory to remain inside the canonical version root and workspace; otherwise treat it as a symlink escape. Read version_manifest.json only from that exact directory. The manifest version_id must equal expected_version_id; for normal phase work it therefore must also equal current.json.active_version.
4. Before using each required phase_paths value, require a non-empty workspace-relative string. Reject an absolute path and any .. path segment. Resolve <workspace>/<phase_path> canonically, including existing symlink ancestors even when the leaf will be created, and require the target to be the intended version directory or a descendant of it. A symlink escape outside that directory is invalid.
5. On any identity or path failure, stop before phase artifact reads, writes, directory creation, commands, or handoffs. Do not normalize an unsafe path into acceptance and do not fall back to a default phase path.

Block examples when expected_version_id is v001 include strategy_store/v001/../v002/04_spec_build, strategy_store/v002/04_spec_build, /tmp/04_spec_build, and strategy_store/v001/escape/04_spec_build when escape is a symlink whose target is outside the intended version directory. An allowed custom nested phase path is strategy_store/v001/custom/phases/04_spec_build when its canonical target remains under the intended version directory.

For a new-version bootstrap, only manage-strategy-version may proceed before the new manifest exists or the new id becomes active. It must apply the same workspace-relative, traversal, canonical-containment, and symlink checks to every constructed phase path before directory creation, then write a matching manifest before publishing current.json last.