Files
codex/codex-rs/core
viyatb-oai 5597925155 feat(cli): add sandbox profile config controls (#20118)
## Why

The explicit profile path from #20117 is meant for standalone testing,
but it still inherited the
shell cwd and all managed requirements implicitly. The pre-existing
launcher path even called out
that it did not support a separate cwd yet in

[`debug_sandbox.rs`](509453f688/codex-rs/cli/src/debug_sandbox.rs (L174-L179)).

For a standalone command, the useful default is to let the caller choose
the project directory being
tested and to avoid administrator-provided constraints unless the caller
explicitly wants to test
those too.

## What changed

- Add explicit-profile-only `-C/--cd DIR`, and use that cwd for both
profile resolution and command
  execution.
- Add explicit-profile-only `--include-managed-config`.
- Make explicit profile mode skip managed requirement sources by
default, including cloud
requirements, MDM requirements, `/etc/codex/requirements.toml`, and the
legacy managed-config
  requirements projection.
- Preserve all existing invocations outside the explicit-profile path.

## Stack

1. #20117 `sandbox-ui-profile`
2. #20118 `sandbox-ui-config` --> this PR

Both PRs are additive. Replay JSON is intentionally deferred to a
follow-up design pass.

## Tests ran

- `cargo test -p codex-cli debug_sandbox`
- `cargo test -p codex-cli sandbox_macos_`
- `cargo test -p codex-core
load_config_layers_can_ignore_managed_requirements`
- `cargo test -p codex-core
load_config_layers_includes_cloud_requirements`
- macOS branch-binary smoke on the rebased top of stack: `-C` changed
execution cwd, explicit
profile mode omitted managed proxy env under `env -i`, and
`--include-managed-config` restored it.
- Linux devbox branch-binary smoke on the rebased top of stack: `-C`
changed execution cwd for
  built-in and user-defined explicit profiles.
2026-04-29 06:55:51 +00:00
..

codex-core

This crate implements the business logic for Codex. It is designed to be used by the various Codex UIs written in Rust.

Dependencies

Note that codex-core makes some assumptions about certain helper utilities being available in the environment. Currently, this support matrix is:

macOS

Expects /usr/bin/sandbox-exec to be present.

When using the workspace-write sandbox policy, the Seatbelt profile allows writes under the configured writable roots while keeping .git (directory or pointer file), the resolved gitdir: target, and .codex read-only.

Network access and filesystem read/write roots are controlled by SandboxPolicy. Seatbelt consumes the resolved policy and enforces it.

Seatbelt also keeps the legacy default preferences read access (user-preference-read) needed for cfprefs-backed macOS behavior.

Linux

Expects the binary containing codex-core to run the equivalent of codex sandbox linux (legacy alias: codex debug landlock) when arg0 is codex-linux-sandbox. See the codex-arg0 crate for details.

Legacy SandboxPolicy / sandbox_mode configs are still supported on Linux. They can continue to use the legacy Landlock path when the split filesystem policy is sandbox-equivalent to the legacy model after cwd resolution. Split filesystem policies that need direct FileSystemSandboxPolicy enforcement, such as read-only or denied carveouts under a broader writable root, automatically route through bubblewrap. The legacy Landlock path is used only when the split filesystem policy round-trips through the legacy SandboxPolicy model without changing semantics. That includes overlapping cases like /repo = write, /repo/a = none, /repo/a/b = write, where the more specific writable child must reopen under a denied parent.

The Linux sandbox helper prefers the first bwrap found on PATH outside the current working directory whenever it is available. If bwrap is present but too old to support --argv0, the helper keeps using system bubblewrap and switches to a no---argv0 compatibility path for the inner re-exec. If bwrap is missing, it falls back to the vendored bubblewrap path compiled into the binary and Codex surfaces a startup warning through its normal notification path instead of printing directly from the sandbox helper. Codex also surfaces a startup warning when bubblewrap cannot create user namespaces. WSL2 uses the normal Linux bubblewrap path. WSL1 is not supported for bubblewrap sandboxing because it cannot create the required user namespaces, so Codex rejects sandboxed shell commands that would enter the bubblewrap path before invoking bwrap.

Windows

Legacy SandboxPolicy / sandbox_mode configs are still supported on Windows. Legacy read-only and workspace-write policies imply full filesystem read access; exact readable roots are represented by split filesystem policies instead.

The elevated Windows sandbox also supports:

  • legacy ReadOnly and WorkspaceWrite behavior
  • split filesystem policies that need exact readable roots, exact writable roots, or extra read-only carveouts under writable roots
  • backend-managed system read roots required for basic execution, such as C:\Windows, C:\Program Files, C:\Program Files (x86), and C:\ProgramData, when a split filesystem policy requests platform defaults

The unelevated restricted-token backend still supports the legacy full-read Windows model for legacy ReadOnly and WorkspaceWrite behavior. It also supports a narrow split-filesystem subset: full-read split policies whose writable roots still match the legacy WorkspaceWrite root set, but add extra read-only carveouts under those writable roots.

New [permissions] / split filesystem policies remain supported on Windows only when they can be enforced directly by the selected Windows backend or round-trip through the legacy SandboxPolicy model without changing semantics. Policies that would require direct explicit unreadable carveouts (none) or reopened writable descendants under read-only carveouts still fail closed instead of running with weaker enforcement.

All Platforms

Expects the binary containing codex-core to simulate the virtual apply_patch CLI when arg1 is --codex-run-as-apply-patch. See the codex-arg0 crate for details.