## Why
`PermissionProfile` is the canonical runtime permission model in the
Rust workspace, but the Linux sandbox helper still accepted a legacy
`SandboxPolicy` plus separate filesystem and network policy flags. That
translation layer made the helper interface harder to reason about and
left `linux-sandbox`-specific callers and tests coupled to the legacy
policy representation.
This change moves the helper onto `PermissionProfile` directly so the
Linux sandbox plumbing matches the rest of the permission stack.
## What changed
- changed `codex-linux-sandbox` to accept `--permission-profile` and
derive the runtime filesystem and network policies internally
- updated the in-process seccomp and legacy Landlock path in
`codex-rs/linux-sandbox` to operate on `PermissionProfile`
- updated Linux sandbox argv construction in `codex-rs/sandboxing`,
`codex-rs/core`, and the CLI debug sandbox path to pass the canonical
profile instead of serializing compatibility policy projections
- simplified the Linux sandbox tests to build the exact permission
profile under test, including the managed-proxy path and
direct-runtime-enforcement carveout coverage
- removed helper-local `SandboxPolicy` usage from `bwrap` tests where
`FileSystemSandboxPolicy` is already the value being exercised
## Testing
- `cargo test -p codex-sandboxing`
- `cargo test -p codex-linux-sandbox` (on this macOS host, the crate
compiled cleanly and its Linux-only tests were cfg-gated)
- `cargo test -p codex-core --no-run`
- `cargo test -p codex-cli --no-run`
## Why
Runtime decisions should not infer permissions from the lossy legacy
sandbox projection once `PermissionProfile` is available. In particular,
`Disabled` and `External` need to remain distinct, and managed profiles
with split filesystem or deny-read rules should not be collapsed before
approval, network, safety, or analytics code makes decisions.
## What Changed
- Changes managed network proxy setup and network approval logic to use
`PermissionProfile` when deciding whether a managed sandbox is active.
- Migrates patch safety, Guardian/user-shell approval paths, Landlock
helper setup, analytics sandbox classification, and selected
turn/session code to profile-backed permissions.
- Validates command-level profile overrides against the constrained
`PermissionProfile` rather than a strict `SandboxPolicy` round trip.
- Preserves configured deny-read restrictions when command profiles are
narrowed.
- Adds coverage for profile-backed trust, network proxy/approval
behavior, patch safety, analytics classification, and command-profile
narrowing.
## Verification
- `cargo test -p codex-core direct_write_roots`
- `cargo test -p codex-core runtime_roots_to_legacy_projection`
- `cargo test -p codex-app-server
requested_permissions_trust_project_uses_permission_profile_intent`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19393).
* #19395
* #19394
* __->__ #19393
## Why
The profile conversion path still required a `cwd` even when it was only
translating a legacy `SandboxPolicy` into a `PermissionProfile`. That
made profile producers invent an ambient `cwd`, which is exactly the
anchoring we are trying to remove from permission-profile data. A legacy
workspace-write policy can be represented symbolically instead: `:cwd =
write` plus read-only `:project_roots` metadata subpaths.
This PR creates that cwd-free base so the rest of the stack can stop
threading cwd through profile construction. Callers that actually need a
concrete runtime filesystem policy for a specific cwd still have an
explicitly named cwd-bound conversion.
## What Changed
- `PermissionProfile::from_legacy_sandbox_policy` now takes only
`&SandboxPolicy`.
- `FileSystemSandboxPolicy::from_legacy_sandbox_policy` is now the
symbolic, cwd-free projection for profiles.
- The old concrete projection is retained as
`FileSystemSandboxPolicy::from_legacy_sandbox_policy_for_cwd` for
runtime/boundary code that must materialize legacy cwd behavior.
- Workspace-write profiles preserve `CurrentWorkingDirectory` and
`ProjectRoots` special entries instead of materializing cwd into
absolute paths.
## Verification
- `cargo check -p codex-protocol -p codex-core -p
codex-app-server-protocol -p codex-app-server -p codex-exec -p
codex-exec-server -p codex-tui -p codex-sandboxing -p
codex-linux-sandbox -p codex-analytics --tests`
- `just fix -p codex-protocol -p codex-core -p codex-app-server-protocol
-p codex-app-server -p codex-exec -p codex-exec-server -p codex-tui -p
codex-sandboxing -p codex-linux-sandbox -p codex-analytics`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19414).
* #19395
* #19394
* #19393
* #19392
* #19391
* __->__ #19414
## Why
`codex-core` was re-exporting APIs owned by sibling `codex-*` crates,
which made downstream crates depend on `codex-core` as a proxy module
instead of the actual owner crate.
Removing those forwards makes crate boundaries explicit and lets leaf
crates drop unnecessary `codex-core` dependencies. In this PR, this
reduces the dependency on `codex-core` to `codex-login` in the following
files:
```
codex-rs/backend-client/Cargo.toml
codex-rs/mcp-server/tests/common/Cargo.toml
```
## What
- Remove `codex-rs/core/src/lib.rs` re-exports for symbols owned by
`codex-login`, `codex-mcp`, `codex-rollout`, `codex-analytics`,
`codex-protocol`, `codex-shell-command`, `codex-sandboxing`,
`codex-tools`, and `codex-utils-path`.
- Delete the `default_client` forwarding shim in `codex-rs/core`.
- Update in-crate and downstream callsites to import directly from the
owning `codex-*` crate.
- Add direct Cargo dependencies where callsites now target the owner
crate, and remove `codex-core` from `codex-rs/backend-client`.
Fixes#15283.
## Summary
Older system bubblewrap builds reject `--argv0`, which makes our Linux
sandbox fail before the helper can re-exec. This PR keeps using system
`/usr/bin/bwrap` whenever it exists and only falls back to vendored
bwrap when the system binary is missing. That matters on stricter
AppArmor hosts, where the distro bwrap package also provides the policy
setup needed for user namespaces.
For old system bwrap, we avoid `--argv0` instead of switching binaries:
- pass the sandbox helper a full-path `argv0`,
- keep the existing `current_exe() + --argv0` path when the selected
launcher supports it,
- otherwise omit `--argv0` and re-exec through the helper's own
`argv[0]` path, whose basename still dispatches as
`codex-linux-sandbox`.
Also updates the launcher/warning tests and docs so they match the new
behavior: present-but-old system bwrap uses the compatibility path, and
only absent system bwrap falls back to vendored.
### Validation
1. Install Ubuntu 20.04 in a VM
2. Compile codex and run without bubblewrap installed - see a warning
about falling back to the vendored bwrap
3. Install bwrap and verify version is 0.4.0 without `argv0` support
4. run codex and use apply_patch tool without errors
<img width="802" height="631" alt="Screenshot 2026-03-25 at 11 48 36 PM"
src="https://github.com/user-attachments/assets/77248a29-aa38-4d7c-9833-496ec6a458b8"
/>
<img width="807" height="634" alt="Screenshot 2026-03-25 at 11 47 32 PM"
src="https://github.com/user-attachments/assets/5af8b850-a466-489b-95a6-455b76b5050f"
/>
<img width="812" height="635" alt="Screenshot 2026-03-25 at 11 45 45 PM"
src="https://github.com/user-attachments/assets/438074f0-8435-4274-a667-332efdd5cb57"
/>
<img width="801" height="623" alt="Screenshot 2026-03-25 at 11 43 56 PM"
src="https://github.com/user-attachments/assets/0dc8d3f5-e8cf-4218-b4b4-a4f7d9bf02e3"
/>
---------
Co-authored-by: Michael Bolin <mbolin@openai.com>
## Summary
- add a new `codex-sandboxing` crate for sandboxing extraction work
- move the pure Linux sandbox argv builders and their unit tests out of
`codex-core`
- keep `core::landlock` as the spawn wrapper and update direct callers
to use `codex_sandboxing::landlock`
## Testing
- `cargo test -p codex-sandboxing`
- `cargo test -p codex-core landlock`
- `cargo test -p codex-cli debug_sandbox`
- `just argument-comment-lint`
## Notes
- this is step 1 of the move plan aimed at minimizing per-PR diffs
- no re-exports or no-op proxy methods were added
## Problem
On Linux, Codex can be launched from a workspace path that is a symlink
(for example, a symlinked checkout or a symlinked parent directory).
Our sandbox policy intentionally canonicalizes writable/readable roots
to the real filesystem path before building the bubblewrap mounts. That
part is correct and needed for safety.
The remaining bug was that bubblewrap could still inherit the helper
process's logical cwd, which might be the symlinked alias instead of the
mounted canonical path. In that case, the sandbox starts in a cwd that
does not exist inside the sandbox namespace even though the real
workspace is mounted. This can cause sandboxed commands to fail in
symlinked workspaces.
## Fix
This PR keeps the sandbox policy behavior the same, but separates two
concepts that were previously conflated:
- the canonical cwd used to define sandbox mounts and permissions
- the caller's logical cwd used when launching the command
On the Linux bubblewrap path, we now thread the logical command cwd
through the helper explicitly and only add `--chdir <canonical path>`
when the logical cwd differs from the mounted canonical path.
That means:
- permissions are still computed from canonical paths
- bubblewrap starts the command from a cwd that definitely exists inside
the sandbox
- we do not widen filesystem access or undo the earlier symlink
hardening
## Why This Is Safe
This is a narrow Linux-only launch fix, not a policy change.
- Writable/readable root canonicalization stays intact.
- Protected metadata carveouts still operate on canonical roots.
- We only override bubblewrap's inherited cwd when the logical path
would otherwise point at a symlink alias that is not mounted in the
sandbox.
## Tests
- kept the existing protocol/core regression coverage for symlink
canonicalization
- added regression coverage for symlinked cwd handling in the Linux
bubblewrap builder/helper path
Local validation:
- `just fmt`
- `cargo test -p codex-protocol`
- `cargo test -p codex-core
normalize_additional_permissions_canonicalizes_symlinked_write_paths`
- `cargo clippy -p codex-linux-sandbox -p codex-protocol -p codex-core
--tests -- -D warnings`
- `cargo build --bin codex`
## Context
This is related to #14694. The earlier writable-root symlink fix
addressed the mount/permission side; this PR fixes the remaining
symlinked-cwd launch mismatch in the Linux sandbox path.
## Why
Once the repo-local lint exists, `codex-rs` needs to follow the
checked-in convention and CI needs to keep it from drifting. This commit
applies the fallback `/*param*/` style consistently across existing
positional literal call sites without changing those APIs.
The longer-term preference is still to avoid APIs that require comments
by choosing clearer parameter types and call shapes. This PR is
intentionally the mechanical follow-through for the places where the
existing signatures stay in place.
After rebasing onto newer `main`, the rollout also had to cover newly
introduced `tui_app_server` call sites. That made it clear the first cut
of the CI job was too expensive for the common path: it was spending
almost as much time installing `cargo-dylint` and re-testing the lint
crate as a representative test job spends running product tests. The CI
update keeps the full workspace enforcement but trims that extra
overhead from ordinary `codex-rs` PRs.
## What changed
- keep a dedicated `argument_comment_lint` job in `rust-ci`
- mechanically annotate remaining opaque positional literals across
`codex-rs` with exact `/*param*/` comments, including the rebased
`tui_app_server` call sites that now fall under the lint
- keep the checked-in style aligned with the lint policy by using
`/*param*/` and leaving string and char literals uncommented
- cache `cargo-dylint`, `dylint-link`, and the relevant Cargo
registry/git metadata in the lint job
- split changed-path detection so the lint crate's own `cargo test` step
runs only when `tools/argument-comment-lint/*` or `rust-ci.yml` changes
- continue to run the repo wrapper over the `codex-rs` workspace, so
product-code enforcement is unchanged
Most of the code changes in this commit are intentionally mechanical
comment rewrites or insertions driven by the lint itself.
## Verification
- `./tools/argument-comment-lint/run.sh --workspace`
- `cargo test -p codex-tui-app-server -p codex-tui`
- parsed `.github/workflows/rust-ci.yml` locally with PyYAML
---
* -> #14652
* #14651
## Why
PR #13783 moved the `codex.rs` unit tests into `codex_tests.rs`. This
applies the same extraction pattern across the rest of `codex-rs/core`
so the production modules stay focused on runtime code instead of large
inline test blocks.
Keeping the tests in sibling files also makes follow-up edits easier to
review because product changes no longer have to share a file with
hundreds or thousands of lines of test scaffolding.
## What changed
- replaced each inline `mod tests { ... }` in `codex-rs/core/src/**`
with a path-based module declaration
- moved each extracted unit test module into a sibling `*_tests.rs`
file, using `mod_tests.rs` for `mod.rs` modules
- preserved the existing `cfg(...)` guards and module-local structure so
the refactor remains structural rather than behavioral
## Testing
- `cargo test -p codex-core --lib` (`1653 passed; 0 failed; 5 ignored`)
- `just fix -p codex-core`
- `cargo fmt --check`
- `cargo shear`
## Summary
- make bubblewrap the default Linux sandbox and keep
`use_legacy_landlock` as the only override
- remove `use_linux_sandbox_bwrap` from feature, config, schema, and
docs surfaces
- update Linux sandbox selection, CLI/config plumbing, and related
tests/docs to match the new default
- fold in the follow-up CI fixes for request-permissions responses and
Linux read-only sandbox error text
## Summary
This is a fast follow to the initial `[permissions]` structure.
- keep the new split-policy carveout behavior for narrower non-write
entries under broader writable roots
- preserve legacy `WorkspaceWrite` semantics by using a cwd-aware bridge
that drops only redundant nested readable roots when projecting from
`SandboxPolicy`
- route the legacy macOS seatbelt adapter through that same legacy
bridge so redundant nested readable roots do not become read-only
carveouts on macOS
- derive the legacy bridge for `command_exec` using the sandbox root cwd
rather than the request cwd so policy derivation matches later sandbox
enforcement
- add regression coverage for the legacy macOS nested-readable-root case
## Examples
### Legacy `workspace-write` on macOS
A legacy `workspace-write` policy can redundantly list a nested readable
root under an already-writable workspace root.
For example, legacy config can effectively mean:
- workspace root (`.` / `cwd`) is writable
- `docs/` is also listed in `readable_roots`
The new shared split-policy helper intentionally treats a narrower
non-write entry under a broader writable root as a carveout for real
`[permissions]` configs. Without this fast follow, the unchanged macOS
seatbelt legacy adapter could project that legacy shape into a
`FileSystemSandboxPolicy` that treated `docs/` like a read-only carveout
under the writable workspace root. In practice, legacy callers on macOS
could unexpectedly lose write access inside `docs/`, even though that
path was writable before the `[permissions]` migration work.
This change fixes that by routing the legacy seatbelt path through the
cwd-aware legacy bridge, so:
- legacy `workspace-write` keeps `docs/` writable when `docs/` was only
a redundant readable root
- explicit `[permissions]` entries like `'.' = 'write'` and `'docs' =
'read'` still make `docs/` read-only, which is the new intended
split-policy behavior
### Legacy `command_exec` with a subdirectory cwd
`command_exec` can run a command from a request cwd that is narrower
than the sandbox root cwd.
For example:
- sandbox root cwd is `/repo`
- request cwd is `/repo/subdir`
- legacy policy is still `workspace-write` rooted at `/repo`
Before this fast follow, `command_exec` derived the legacy bridge using
the request cwd, but the sandbox was later built using the sandbox root
cwd. That mismatch could miss redundant legacy readable roots during
projection and accidentally reintroduce read-only carveouts for paths
that should still be writable under the legacy model.
This change fixes that by deriving the legacy bridge with the same
sandbox root cwd that sandbox enforcement later uses.
## Verification
- `just fmt`
- `cargo test -p codex-core
seatbelt_legacy_workspace_write_nested_readable_root_stays_writable`
- `cargo test -p codex-core test_sandbox_config_parsing`
- `cargo clippy -p codex-core -p codex-app-server --all-targets -- -D
warnings`
- `cargo clean`
## Why
The Linux sandbox helper still only accepted the legacy `SandboxPolicy`
payload.
That meant the runtime could compute split filesystem and network
policies, but the helper would immediately collapse them back to the
compatibility projection before applying seccomp or staging the
bubblewrap inner command.
## What changed
- added hidden `--file-system-sandbox-policy` and
`--network-sandbox-policy` flags alongside the legacy `--sandbox-policy`
flag so the helper can migrate incrementally
- updated the core-side Landlock wrapper to pass the split policies
explicitly when launching `codex-linux-sandbox`
- added helper-side resolution logic that accepts either the legacy
policy alone or a complete split-policy pair and normalizes that into
one effective configuration
- switched Linux helper network decisions to use `NetworkSandboxPolicy`
directly
- added `FromStr` support for the split policy types so the helper can
parse them from CLI JSON
## Verification
- added helper coverage in `linux-sandbox/src/linux_run_main_tests.rs`
for split-policy flags and policy resolution
- added CLI argument coverage in `core/src/landlock.rs`
- verified the current PR state with `just clippy`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/13449).
* #13453
* #13452
* #13451
* __->__ #13449
* #13448
* #13445
* #13440
* #13439
---------
Co-authored-by: viyatb-oai <viyatb@openai.com>
## Why
`#13434` introduces split `FileSystemSandboxPolicy` and
`NetworkSandboxPolicy`, but the runtime still made most execution-time
sandbox decisions from the legacy `SandboxPolicy` projection.
That projection loses information about combinations like unrestricted
filesystem access with restricted network access. In practice, that
means the runtime can choose the wrong platform sandbox behavior or set
the wrong network-restriction environment for a command even when config
has already separated those concerns.
This PR carries the split policies through the runtime so sandbox
selection, process spawning, and exec handling can consult the policy
that actually matters.
## What changed
- threaded `FileSystemSandboxPolicy` and `NetworkSandboxPolicy` through
`TurnContext`, `ExecRequest`, sandbox attempts, shell escalation state,
unified exec, and app-server exec overrides
- updated sandbox selection in `core/src/sandboxing/mod.rs` and
`core/src/exec.rs` to key off `FileSystemSandboxPolicy.kind` plus
`NetworkSandboxPolicy`, rather than inferring behavior only from the
legacy `SandboxPolicy`
- updated process spawning in `core/src/spawn.rs` and the platform
wrappers to use `NetworkSandboxPolicy` when deciding whether to set
`CODEX_SANDBOX_NETWORK_DISABLED`
- kept additional-permissions handling and legacy `ExternalSandbox`
compatibility projections aligned with the split policies, including
explicit user-shell execution and Windows restricted-token routing
- updated callers across `core`, `app-server`, and `linux-sandbox` to
pass the split policies explicitly
## Verification
- added regression coverage in `core/tests/suite/user_shell_cmd.rs` to
verify `RunUserShellCommand` does not inherit
`CODEX_SANDBOX_NETWORK_DISABLED` from the active turn
- added coverage in `core/src/exec.rs` for Windows restricted-token
sandbox selection when the legacy projection is `ExternalSandbox`
- updated Linux sandbox coverage in
`linux-sandbox/tests/suite/landlock.rs` to exercise the split-policy
exec path
- verified the current PR state with `just clippy`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/13439).
* #13453
* #13452
* #13451
* #13449
* #13448
* #13445
* #13440
* __->__ #13439
---------
Co-authored-by: viyatb-oai <viyatb@openai.com>
`SandboxPolicy::ReadOnly` previously implied broad read access and could
not express a narrower read surface.
This change introduces an explicit read-access model so we can support
user-configurable read restrictions in follow-up work, while preserving
current behavior today.
It also ensures unsupported backends fail closed for restricted-read
policies instead of silently granting broader access than intended.
## What
- Added `ReadOnlyAccess` in protocol with:
- `Restricted { include_platform_defaults, readable_roots }`
- `FullAccess`
- Updated `SandboxPolicy` to carry read-access configuration:
- `ReadOnly { access: ReadOnlyAccess }`
- `WorkspaceWrite { ..., read_only_access: ReadOnlyAccess }`
- Preserved existing behavior by defaulting current construction paths
to `ReadOnlyAccess::FullAccess`.
- Threaded the new fields through sandbox policy consumers and call
sites across `core`, `tui`, `linux-sandbox`, `windows-sandbox`, and
related tests.
- Updated Seatbelt policy generation to honor restricted read roots by
emitting scoped read rules when full read access is not granted.
- Added fail-closed behavior on Linux and Windows backends when
restricted read access is requested but not yet implemented there
(`UnsupportedOperation`).
- Regenerated app-server protocol schema and TypeScript artifacts,
including `ReadOnlyAccess`.
## Compatibility / rollout
- Runtime behavior remains unchanged by default (`FullAccess`).
- API/schema changes are in place so future config wiring can enable
restricted read access without another policy-shape migration.
## Summary
This PR introduces a gated Bubblewrap (bwrap) Linux sandbox path. The
curent Linux sandbox path relies on in-process restrictions (including
Landlock). Bubblewrap gives us a more uniform filesystem isolation
model, especially explicit writable roots with the option to make some
directories read-only and granular network controls.
This is behind a feature flag so we can validate behavior safely before
making it the default.
- Added temporary rollout flag:
- `features.use_linux_sandbox_bwrap`
- Preserved existing default path when the flag is off.
- In Bubblewrap mode:
- Added internal retry without /proc when /proc mount is not permitted
by the host/container.
The high-order bit on this PR is that it makes it so `sandbox.rs` tests
both Mac and Linux, as we introduce a general
`spawn_command_under_sandbox()` function with platform-specific
implementations for testing.
An important, and interesting, discovery in porting the test to Linux is
that (for reasons cited in the code comments), `/dev/shm` has to be
added to `writable_roots` on Linux in order for `multiprocessing.Lock`
to work there. Granting write access to `/dev/shm` comes with some
degree of risk, so we do not make this the default for Codex CLI.
Piggybacking on top of #2317, this moves the
`python_multiprocessing_lock_works` test yet again, moving
`codex-rs/core/tests/sandbox.rs` to `codex-rs/exec/tests/sandbox.rs`
because in `codex-rs/exec/tests` we can use `cargo_bin()` like so:
```
let codex_linux_sandbox_exe = assert_cmd::cargo::cargo_bin("codex-exec");
```
which is necessary so we can use `codex_linux_sandbox_exe` and therefore
`spawn_command_under_linux_sandbox` in an integration test.
This also moves `spawn_command_under_linux_sandbox()` out of `exec.rs`
and into `landlock.rs`, which makes things more consistent with
`seatbelt.rs` in `codex-core`.
For reference, https://github.com/openai/codex/pull/1808 is the PR that
made the change to Seatbelt to get this test to pass on Mac.
Historically, we spawned the Seatbelt and Landlock sandboxes in
substantially different ways:
For **Seatbelt**, we would run `/usr/bin/sandbox-exec` with our policy
specified as an arg followed by the original command:
d1de7bb383/codex-rs/core/src/exec.rs (L147-L219)
For **Landlock/Seccomp**, we would do
`tokio::runtime::Builder::new_current_thread()`, _invoke
Landlock/Seccomp APIs to modify the permissions of that new thread_, and
then spawn the command:
d1de7bb383/codex-rs/core/src/exec_linux.rs (L28-L49)
While it is neat that Landlock/Seccomp supports applying a policy to
only one thread without having to apply it to the entire process, it
requires us to maintain two different codepaths and is a bit harder to
reason about. The tipping point was
https://github.com/openai/codex/pull/1061, in which we had to start
building up the `env` in an unexpected way for the existing
Landlock/Seccomp approach to continue to work.
This PR overhauls things so that we do similar things for Mac and Linux.
It turned out that we were already building our own "helper binary"
comparable to Mac's `sandbox-exec` as part of the `cli` crate:
d1de7bb383/codex-rs/cli/Cargo.toml (L10-L12)
We originally created this to build a small binary to include with the
Node.js version of the Codex CLI to provide support for Linux
sandboxing.
Though the sticky bit is that, at this point, we still want to deploy
the Rust version of Codex as a single, standalone binary rather than a
CLI and a supporting sandboxing binary. To satisfy this goal, we use
"the arg0 trick," in which we:
* use `std::env::current_exe()` to get the path to the CLI that is
currently running
* use the CLI as the `program` for the `Command`
* set `"codex-linux-sandbox"` as arg0 for the `Command`
A CLI that supports sandboxing should check arg0 at the start of the
program. If it is `"codex-linux-sandbox"`, it must invoke
`codex_linux_sandbox::run_main()`, which runs the CLI as if it were
`codex-linux-sandbox`. When acting as `codex-linux-sandbox`, we make the
appropriate Landlock/Seccomp API calls and then use `execvp(3)` to spawn
the original command, so do _replace_ the process rather than spawn a
subprocess. Incidentally, we do this before starting the Tokio runtime,
so the process should only have one thread when `execvp(3)` is called.
Because the `core` crate that needs to spawn the Linux sandboxing is not
a CLI in its own right, this means that every CLI that includes `core`
and relies on this behavior has to (1) implement it and (2) provide the
path to the sandboxing executable. While the path is almost always
`std::env::current_exe()`, we needed to make this configurable for
integration tests, so `Config` now has a `codex_linux_sandbox_exe:
Option<PathBuf>` property to facilitate threading this through,
introduced in https://github.com/openai/codex/pull/1089.
This common pattern is now captured in
`codex_linux_sandbox::run_with_sandbox()` and all of the `main.rs`
functions that should use it have been updated as part of this PR.
The `codex-linux-sandbox` crate added to the Cargo workspace as part of
this PR now has the bulk of the Landlock/Seccomp logic, which makes
`core` a bit simpler. Indeed, `core/src/exec_linux.rs` and
`core/src/landlock.rs` were removed/ported as part of this PR. I also
moved the unit tests for this code into an integration test,
`linux-sandbox/tests/landlock.rs`, in which I use
`env!("CARGO_BIN_EXE_codex-linux-sandbox")` as the value for
`codex_linux_sandbox_exe` since `std::env::current_exe()` is not
appropriate in that case.
To date, when handling `shell` and `local_shell` tool calls, we were
spawning new processes using the environment inherited from the Codex
process itself. This means that the sensitive `OPENAI_API_KEY` that
Codex needs to talk to OpenAI models was made available to everything
run by `shell` and `local_shell`. While there are cases where that might
be useful, it does not seem like a good default.
This PR introduces a complex `shell_environment_policy` config option to
control the `env` used with these tool calls. It is inevitably a bit
complex so that it is possible to override individual components of the
policy so without having to restate the entire thing.
Details are in the updated `README.md` in this PR, but here is the
relevant bit that explains the individual fields of
`shell_environment_policy`:
| Field | Type | Default | Description |
| ------------------------- | -------------------------- | ------- |
-----------------------------------------------------------------------------------------------------------------------------------------------
|
| `inherit` | string | `core` | Starting template for the
environment:<br>`core` (`HOME`, `PATH`, `USER`, …), `all` (clone full
parent env), or `none` (start empty). |
| `ignore_default_excludes` | boolean | `false` | When `false`, Codex
removes any var whose **name** contains `KEY`, `SECRET`, or `TOKEN`
(case-insensitive) before other rules run. |
| `exclude` | array<string> | `[]` | Case-insensitive glob
patterns to drop after the default filter.<br>Examples: `"AWS_*"`,
`"AZURE_*"`. |
| `set` | table<string,string> | `{}` | Explicit key/value
overrides or additions – always win over inherited values. |
| `include_only` | array<string> | `[]` | If non-empty, a
whitelist of patterns; only variables that match _one_ pattern survive
the final step. (Generally used with `inherit = "all"`.) |
In particular, note that the default is `inherit = "core"`, so:
* if you have extra env variables that you want to inherit from the
parent process, use `inherit = "all"` and then specify `include_only`
* if you have extra env variables where you want to hardcode the values,
the default `inherit = "core"` will work fine, but then you need to
specify `set`
This configuration is not battle-tested, so we will probably still have
to play with it a bit. `core/src/exec_env.rs` has the critical business
logic as well as unit tests.
Though if nothing else, previous to this change:
```
$ cargo run --bin codex -- debug seatbelt -- printenv OPENAI_API_KEY
# ...prints OPENAI_API_KEY...
```
But after this change it does not print anything (as desired).
One final thing to call out about this PR is that the
`configure_command!` macro we use in `core/src/exec.rs` has to do some
complex logic with respect to how it builds up the `env` for the process
being spawned under Landlock/seccomp. Specifically, doing
`cmd.env_clear()` followed by `cmd.envs(&$env_map)` (which is arguably
the most intuitive way to do it) caused the Landlock unit tests to fail
because the processes spawned by the unit tests started failing in
unexpected ways! If we forgo `env_clear()` in favor of updating env vars
one at a time, the tests still pass. The comment in the code talks about
this a bit, and while I would like to investigate this more, I need to
move on for the moment, but I do plan to come back to it to fully
understand what is going on. For example, this suggests that we might
not be able to spawn a C program that calls `env_clear()`, which would
be...weird. We may still have to fiddle with our Landlock config if that
is the case.
I believe this test meant to verify that echoing content to `/dev/null`
succeeded, but instead, I believe it was testing the equivalent to `echo
'blah > /dev/null'`.
Adds `expect()` as a denied lint. Same deal applies with `unwrap()`
where we now need to put `#[expect(...` on ones that we legit want. Took
care to enable `expect()` in test contexts.
# Tests
```
cargo fmt
cargo clippy --all-features --all-targets --no-deps -- -D warnings
cargo test
```
When using Codex to develop Codex itself, I noticed that sometimes it
would try to add `#[ignore]` to the following tests:
```
keeps_previous_response_id_between_tasks()
retries_on_early_close()
```
Both of these tests start a `MockServer` that launches an HTTP server on
an ephemeral port and requires network access to hit it, which the
Seatbelt policy associated with `--full-auto` correctly denies. If I
wasn't paying attention to the code that Codex was generating, one of
these `#[ignore]` annotations could have slipped into the codebase,
effectively disabling the test for everyone.
To that end, this PR enables an experimental environment variable named
`CODEX_SANDBOX_NETWORK_DISABLED` that is set to `1` if the
`SandboxPolicy` used to spawn the process does not have full network
access. I say it is "experimental" because I'm not convinced this API is
quite right, but we need to start somewhere. (It might be more
appropriate to have an env var like `CODEX_SANDBOX=full-auto`, but the
challenge is that our newer `SandboxPolicy` abstraction does not map to
a simple set of enums like in the TypeScript CLI.)
We leverage this new functionality by adding the following code to the
aforementioned tests as a way to "dynamically disable" them:
```rust
if std::env::var(CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR).is_ok() {
println!(
"Skipping test because it cannot execute when network is disabled in a Codex sandbox."
);
return;
}
```
We can use the `debug seatbelt --full-auto` command to verify that
`cargo test` fails when run under Seatbelt prior to this change:
```
$ cargo run --bin codex -- debug seatbelt --full-auto -- cargo test
---- keeps_previous_response_id_between_tasks stdout ----
thread 'keeps_previous_response_id_between_tasks' panicked at /Users/mbolin/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/wiremock-0.6.3/src/mock_server/builder.rs:107:46:
Failed to bind an OS port for a mock server.: Os { code: 1, kind: PermissionDenied, message: "Operation not permitted" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
keeps_previous_response_id_between_tasks
test result: FAILED. 0 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
error: test failed, to rerun pass `-p codex-core --test previous_response_id`
```
Though after this change, the above command succeeds! This means that,
going forward, when Codex operates on Codex itself, when it runs `cargo
test`, only "real failures" should cause the command to fail.
As part of this change, I decided to tighten up the codepaths for
running `exec()` for shell tool calls. In particular, we do it in `core`
for the main Codex business logic itself, but we also expose this logic
via `debug` subcommands in the CLI in the `cli` crate. The logic for the
`debug` subcommands was not quite as faithful to the true business logic
as I liked, so I:
* refactored a bit of the Linux code, splitting `linux.rs` into
`linux_exec.rs` and `landlock.rs` in the `core` crate.
* gating less code behind `#[cfg(target_os = "linux")]` because such
code does not get built by default when I develop on Mac, which means I
either have to build the code in Docker or wait for CI signal
* introduced `macro_rules! configure_command` in `exec.rs` so we can
have both sync and async versions of this code. The synchronous version
seems more appropriate for straight threads or potentially fork/exec.
