Files
codex/codex-rs/core
Michael BolinandGitHub bf38def44e permissions: make SessionConfigured profile-only (#19774)
## Why

`SessionConfiguredEvent` is the internal event that tells clients what
permissions are active for a session. Emitting both `sandbox_policy` and
`permission_profile` leaves two possible authorities and forces every
consumer to decide which one to honor. At this point in the migration,
the profile is expressive enough to represent managed, disabled, and
external sandbox enforcement, so the internal event can be profile-only.

The wire compatibility concern is older serialized events or rollout
data that only contain `sandbox_policy`; those still need to
deserialize.

## What Changed

- Removes `sandbox_policy` from `SessionConfiguredEvent` and makes
`permission_profile` required.
- Adds custom deserialization so old payloads with only `sandbox_policy`
are upgraded to a cwd-anchored `PermissionProfile`.
- Updates core event emission and TUI session handling to sync
permissions from the profile directly.
- Updates app-server response construction to derive the legacy
`sandbox` response field from the active thread snapshot instead of from
`SessionConfiguredEvent`.
- Updates yolo-mode display logic to treat both
`PermissionProfile::Disabled` and managed unrestricted filesystem plus
enabled network as full-access, while still preserving the distinction
between no sandbox and external sandboxing.

## Verification

- `cargo test -p codex-protocol session_configured_event --lib`
- `cargo test -p codex-protocol serialize_event --lib`
- `cargo test -p codex-exec session_configured --lib`
- `cargo test -p codex-app-server
thread_response_permission_profile_preserves_enforcement --lib`
- `cargo test -p codex-core
session_configured_reports_permission_profile_for_external_sandbox
--lib`
- `cargo test -p codex-tui session_configured --lib`
- `cargo test -p codex-tui
yolo_mode_includes_managed_full_access_profiles --lib`


































---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19774).
* #19900
* #19899
* #19776
* #19775
* __->__ #19774
2026-04-27 22:06:47 -07:00
..

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.