feat(sandbox): cross-family file sandbox — one policy home, sandboxed fs provider, fs escalation parity

Extend SandboxMode enforcement from bash to the filesystem tools, the sandbox
RFC's deferred cross-family phase.

- dsh-sandbox-policy (new, ctx.sandboxPolicy): the single home for the
  deployment default mode + workspaceRoot and the per-session override event,
  renamed bash/sandbox-mode -> sandbox/mode and moved here with its fold/setter.
  Decouples the bash seam from dsh-session.
- dsh-fs-sandbox (new): SandboxedFileSystem extends LocalFileSystem and fences
  write/edit by the per-call mode (read-only denies, workspace-write contains to
  the workspace + temp roots via the shared writableRoots, danger passes
  through); reads pass through. Structured FS_SANDBOX_DENIED; in-lock parent
  re-canonicalization. A policy fence in trusted code, not a kernel boundary.
- dsh-sandbox: the shared escalation kit (writableRoots, the strictly-wider
  ladder, denial/hint markers, approveEscalation) both tool families use;
  approveEscalation takes a structural approver so dsh-sandbox gains no
  approval/agent dependency, and both tools stay duplication-free.
- tool-fs: write/edit advertise sandbox_permissions/justification under a
  confining ctx.fs, map FS_SANDBOX_DENIED to the shared [sandbox: ...] marker,
  and resolve the same one-approved-wider retry.
- examples/acp-agent: composes sandbox-policy + fs-sandbox, drops the gating
  that disabled the fs stack under confined modes.

RFC docs/rfc/implemented/feature/2026-07-14-cross-family-fs-sandbox.md; the old
sandbox RFC's In-process/deferred/FAQ sections updated to shipped fact.
This commit is contained in:
kingwl
2026-07-14 20:05:57 +08:00
parent c3137b5474
commit 2dc62497ce
100 changed files with 2238 additions and 385 deletions

View File

@@ -132,6 +132,7 @@ type FsErrorCode =
| 'FS_NOT_TEXT'
| 'FS_NOT_REGULAR_FILE'
| 'FS_PERMISSION_DENIED'
| 'FS_SANDBOX_DENIED'
| 'FS_IO_ERROR'
| 'FS_STALE_VERSION'
| 'FS_NOT_OBSERVED'
@@ -140,7 +141,7 @@ type FsErrorCode =
| 'FS_ABORTED'
```
`FS_NOT_DIRECTORY`, `FS_PERMISSION_DENIED`, and `FS_IO_ERROR` are used by directory listing to distinguish an existing non-directory target, a denied listing, and an unexpected backend I/O failure. `FS_NOT_OBSERVED` means the policy plugin has no prior-observation record for this owner (or a `createIfAbsent` hit an existing file). `FS_STALE_VERSION` means the backend version no longer matches the observed one (or an edit hit a missing target). Freshness authorization has no partial/full distinction, so there is no `FS_PARTIAL_OBSERVATION`.
`FS_NOT_DIRECTORY`, `FS_PERMISSION_DENIED`, and `FS_IO_ERROR` are used by directory listing to distinguish an existing non-directory target, a denied listing, and an unexpected backend I/O failure. `FS_SANDBOX_DENIED` is a POLICY refusal from a sandbox-enforcing backend (`dsh-fs-sandbox`) — the mode fence denied a write/edit — distinct from `FS_PERMISSION_DENIED` (the host kernel refusing). `FS_NOT_OBSERVED` means the policy plugin has no prior-observation record for this owner (or a `createIfAbsent` hit an existing file). `FS_STALE_VERSION` means the backend version no longer matches the observed one (or an edit hit a missing target). Freshness authorization has no partial/full distinction, so there is no `FS_PARTIAL_OBSERVATION`.
## The service and the plugin