Commit Graph

70 Commits

  • fix(linux-sandbox): prefer system /usr/bin/bwrap when available (#14963)
    ## Problem
    Ubuntu/AppArmor hosts started failing in the default Linux sandbox path
    after the switch to vendored/default bubblewrap in `0.115.0`.
    
    The clearest report is in
    [#14919](https://github.com/openai/codex/issues/14919), especially [this
    investigation
    comment](https://github.com/openai/codex/issues/14919#issuecomment-4076504751):
    on affected Ubuntu systems, `/usr/bin/bwrap` works, but a copied or
    vendored `bwrap` binary fails with errors like `bwrap: setting up uid
    map: Permission denied` or `bwrap: loopback: Failed RTM_NEWADDR:
    Operation not permitted`.
    
    The root cause is Ubuntu's `/etc/apparmor.d/bwrap-userns-restrict`
    profile, which grants `userns` access specifically to `/usr/bin/bwrap`.
    Once Codex started using a vendored/internal bubblewrap path, that path
    was no longer covered by the distro AppArmor exception, so sandbox
    namespace setup could fail even when user namespaces were otherwise
    enabled and `uidmap` was installed.
    
    ## What this PR changes
    - prefer system `/usr/bin/bwrap` whenever it is available
    - keep vendored bubblewrap as the fallback when `/usr/bin/bwrap` is
    missing
    - when `/usr/bin/bwrap` is missing, surface a Codex startup warning
    through the app-server/TUI warning path instead of printing directly
    from the sandbox helper with `eprintln!`
    - use the same launcher decision for both the main sandbox execution
    path and the `/proc` preflight path
    - document the updated Linux bubblewrap behavior in the Linux sandbox
    and core READMEs
    
    ## Why this fix
    This still fixes the Ubuntu/AppArmor regression from
    [#14919](https://github.com/openai/codex/issues/14919), but it keeps the
    runtime rule simple and platform-agnostic: if the standard system
    bubblewrap is installed, use it; otherwise fall back to the vendored
    helper.
    
    The warning now follows that same simple rule. If Codex cannot find
    `/usr/bin/bwrap`, it tells the user that it is falling back to the
    vendored helper, and it does so through the existing startup warning
    plumbing that reaches the TUI and app-server instead of low-level
    sandbox stderr.
    
    ## Testing
    - `cargo test -p codex-linux-sandbox`
    - `cargo test -p codex-app-server --lib`
    - `cargo test -p codex-tui-app-server
    tests::embedded_app_server_start_failure_is_returned`
    - `cargo clippy -p codex-linux-sandbox --all-targets`
    - `cargo clippy -p codex-app-server --all-targets`
    - `cargo clippy -p codex-tui-app-server --all-targets`
  • fix(linux-sandbox): ignore missing writable roots (#14890)
    ## Summary
    - skip nonexistent `workspace-write` writable roots in the Linux
    bubblewrap mount builder instead of aborting sandbox startup
    - keep existing writable roots mounted normally so mixed Windows/WSL
    configs continue to work
    - add unit and Linux integration regression coverage for the
    missing-root case
    
    ## Context
    This addresses regression A from #14875. Regression B will be handled in
    a separate PR.
    
    The old bubblewrap integration added `ensure_mount_targets_exist` as a
    preflight guard because bubblewrap bind targets must exist, and failing
    early let Codex return a clearer error than a lower-level mount failure.
    
    That policy turned out to be too strict once bubblewrap became the
    default Linux sandbox: shared Windows/WSL or mixed-platform configs can
    legitimately contain a well-formed writable root that does not exist on
    the current machine. This PR keeps bubblewrap's existing-target
    requirement, but changes Codex to skip missing writable roots instead of
    treating them as fatal configuration errors.
  • fix: canonicalize symlinked Linux sandbox cwd (#14849)
    ## 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.
  • Apply argument comment lint across codex-rs (#14652)
    ## 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
  • Use a private desktop for Windows sandbox instead of Winsta0\Default (#14400)
    ## Summary
    - launch Windows sandboxed children on a private desktop instead of
    `Winsta0\Default`
    - make private desktop the default while keeping
    `windows.sandbox_private_desktop=false` as the escape hatch
    - centralize process launch through the shared
    `create_process_as_user(...)` path
    - scope the private desktop ACL to the launching logon SID
    
    ## Why
    Today sandboxed Windows commands run on the visible shared desktop. That
    leaves an avoidable same-desktop attack surface for window interaction,
    spoofing, and related UI/input issues. This change moves sandboxed
    commands onto a dedicated per-launch desktop by default so the sandbox
    no longer shares `Winsta0\Default` with the user session.
    
    The implementation stays conservative on security with no silent
    fallback back to `Winsta0\Default`
    
    If private-desktop setup fails on a machine, users can still opt out
    explicitly with `windows.sandbox_private_desktop=false`.
    
    ## Validation
    - `cargo build -p codex-cli`
    - elevated-path `codex exec` desktop-name probe returned
    `CodexSandboxDesktop-*`
    - elevated-path `codex exec` smoke sweep for shell commands, nested
    `pwsh`, jobs, and hidden `notepad` launch
    - unelevated-path full private-desktop compatibility sweep via `codex
    exec` with `-c windows.sandbox=unelevated`
  • fix: reopen writable linux carveouts under denied parents (#14514)
    ## Summary
    - preserve Linux bubblewrap semantics for `write -> none -> write`
    filesystem policies by recreating masked mount targets before rebinding
    narrower writable descendants
    - add a Linux runtime regression for `/repo = write`, `/repo/a = none`,
    `/repo/a/b = write` so the nested writable child is exercised under
    bubblewrap
    - document the supported legacy Landlock fallback and the split-policy
    bubblewrap behavior for overlapping carveouts
    
    ## Example
    Given a split filesystem policy like:
    
    ```toml
    "/repo" = "write"
    "/repo/a" = "none"
    "/repo/a/b" = "write"
    ```
    
    this PR keeps `/repo` writable, masks `/repo/a`, and still reopens
    `/repo/a/b` as writable again under bubblewrap.
    
    ## Testing
    - `just fmt`
    - `cargo test -p codex-linux-sandbox`
    - `cargo clippy -p codex-linux-sandbox --tests -- -D warnings`
  • fix: preserve split filesystem semantics in linux sandbox (#14173)
    ## Stack
    
       fix: fail closed for unsupported split windows sandboxing #14172
    -> fix: preserve split filesystem semantics in linux sandbox #14173
       fix: align core approvals with split sandbox policies #14171
       refactor: centralize filesystem permissions precedence #14174
    
    ## Summary
    ## Summary
    - Preserve Linux split filesystem carveouts in bubblewrap by applying
    mount masks in the right order, so narrower rules still win under
    broader writable roots.
    - Preserve unreadable ancestors of writable roots by masking them first
    and then rebinding the narrower writable descendants.
    - Stop rejecting legacy-plus-split Linux configs that are
    sandbox-equivalent after `cwd` resolution by comparing semantics instead
    of raw legacy structs.
    - Fail closed when callers provide partial split policies, mismatched
    legacy-plus-split policies, or force `--use-legacy-landlock` for
    split-only shapes that legacy Landlock cannot enforce.
    - Add Linux regressions for overlapping writable, read-only, and denied
    paths, and document the supported split-policy enforcement path.
    
    ## Example
    Given a split filesystem policy like:
    
    ```toml
    [permissions.dev.filesystem]
    ":root" = "read"
    "/code" = "write"
    "/code/.git" = "read"
    "/code/secrets" = "none"
    "/code/secrets/tmp" = "write"
    ```
    
    this PR makes Linux enforce the intended result under bubblewrap:
    
    - `/code` stays writable
    - `/code/.git` stays read-only
    - `/code/secrets` stays denied
    - `/code/secrets/tmp` can still be reopened as writable if explicitly
    allowed
    
    Before this, Linux could lose one of those carveouts depending on mount
    order or legacy-policy fallback. This PR keeps the split-policy
    semantics intact and rejects configurations that legacy Landlock cannot
    represent safely.
  • fix: follow up on linux sandbox review nits (#14440)
    ## Summary
    - address the follow-up review nits from #13996 in a separate PR
    - make the approvals test command a raw string and keep the
    managed-network path using env proxy routing
    - inline `--apply-seccomp-then-exec` in the Linux sandbox inner command
    builder
    - remove the bubblewrap-specific sandbox metric tag path and drop the
    `use_legacy_landlock` shim from `sandbox_tag`/`TurnMetadataState::new`
    - restore the `Feature` import that `origin/main` currently still needs
    in `connectors.rs`
    
    ## Testing
    - `cargo test -p codex-linux-sandbox`
    - focused `codex-core` tests were rerun/started, but the final
    verification pass was interrupted when I pushed at request
  • refactor: make bubblewrap the default Linux sandbox (#13996)
    ## 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
  • fix(protocol): preserve legacy workspace-write semantics (#13957)
    ## 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`
  • linux-sandbox: honor split filesystem policies in bwrap (#13453)
    ## Why
    
    After `#13449`, the Linux helper could receive split filesystem and
    network policies, but the bubblewrap mount builder still reconstructed
    filesystem access from the legacy `SandboxPolicy`.
    
    That loses explicit unreadable carveouts under writable roots, and it
    also mishandles `Root` read access paired with explicit deny carveouts.
    In those cases bubblewrap could still expose paths that the split
    filesystem policy intentionally blocked.
    
    ## What changed
    
    - switched bubblewrap mount generation to consume
    `FileSystemSandboxPolicy` directly at the implementation boundary;
    legacy `SandboxPolicy` configs still flow through the existing
    `FileSystemSandboxPolicy::from(&sandbox_policy)` bridge before reaching
    bwrap
    - kept the Linux helper and preflight path on the split filesystem
    policy all the way into bwrap
    - re-applied explicit unreadable carveouts after readable and writable
    mounts so blocked subpaths still win under bubblewrap
    - masked denied directories with `--tmpfs` plus `--remount-ro` and
    denied files with `--ro-bind-data`, preserving the backing fd until exec
    - added comments in the unreadable-root masking block to explain why the
    mount order and directory/file split are intentional
    - updated Linux helper call sites and tests for the split-policy bwrap
    path
    
    ## Verification
    
    - added protocol coverage for root carveouts staying scoped
    - added core coverage that root-write plus deny carveouts still requires
    a platform sandbox
    - added bwrap unit coverage for reapplying blocked carveouts after
    writable binds
    - added Linux integration coverage for explicit split-policy carveouts
    under bubblewrap
    - validated the final branch state with `cargo test -p
    codex-linux-sandbox`, `cargo clippy -p codex-linux-sandbox --all-targets
    -- -D warnings`, and the PR CI reruns
    
    ---
    [//]: # (BEGIN SAPLING FOOTER)
    Stack created with [Sapling](https://sapling-scm.com). Best reviewed
    with [ReviewStack](https://reviewstack.dev/openai/codex/pull/13453).
    * __->__ #13453
    * #13452
    * #13451
    * #13449
    * #13448
    * #13445
    * #13440
    * #13439
    
    ---------
    
    Co-authored-by: viyatb-oai <viyatb@openai.com>
  • linux-sandbox: plumb split sandbox policies through helper (#13449)
    ## 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>
  • sandboxing: plumb split sandbox policies through runtime (#13439)
    ## 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>
  • fix(linux-sandbox): always unshare bwrap userns (#13624)
    ## Summary
    - always pass `--unshare-user` in the Linux bubblewrap argv builders
    - stop relying on bubblewrap's auto-userns behavior, which is skipped
    for `uid 0`
    - update argv expectations in tests and document the explicit user
    namespace behavior
    
    The installed Codex binary reproduced the same issue with:
    - `codex -c features.use_linux_sandbox_bwrap=true sandbox linux -- true`
    - `bwrap: Creating new namespace failed: Operation not permitted`
    
    This happens because Codex asked bubblewrap for mount/pid/network
    namespaces without explicitly asking for a user namespace. In a
    root-inside-container environment without ambient `CAP_SYS_ADMIN`, that
    fails. Adding `--unshare-user` makes bubblewrap create the user
    namespace first and then the remaining namespaces succeed.
  • Feat: Preserve network access on read-only sandbox policies (#13409)
    ## Summary
    
    `PermissionProfile.network` could not be preserved when additional or
    compiled permissions resolved to
    `SandboxPolicy::ReadOnly`, because `ReadOnly` had no network_access
    field. This change makes read-only + network
    enabled representable directly and threads that through the protocol,
    app-server v2 mirror, and permission-
      merging logic.
    
    ## What changed
    
    - Added `network_access: bool` to `SandboxPolicy::ReadOnly` in the core
    protocol and app-server v2 protocol.
    - Kept backward compatibility by defaulting the new field to false, so
    legacy read-only payloads still
        deserialize unchanged.
    - Updated `has_full_network_access()` and sandbox summaries to respect
    read-only network access.
      - Preserved PermissionProfile.network when:
          - compiling skill permission profiles into sandbox policies
          - normalizing additional permissions
          - merging additional permissions into existing sandbox policies
    - Updated the approval overlay to show network in the rendered
    permission rule when requested.
      - Regenerated app-server schema fixtures for the new v2 wire shape.
  • feat(linux-sandbox): support restricted ReadOnlyAccess in bwrap (#12369)
    ## Summary
    Implements Linux bubblewrap support for restricted `ReadOnlyAccess`
    (introduced in #11387) by honoring `readable_roots` and
    `include_platform_defaults` instead of failing closed.
    
    ## What changed
    - Added a Linux platform-default read allowlist for common
    system/runtime paths (e.g. /usr, /etc, /lib*, Nix store roots).
    - Updated the bwrap filesystem mount builder to support restricted read
    access:
      - Full-read policies still use `--ro-bind / /`
    - Restricted-read policies now start from` --tmpfs `/ and add scoped
    `--ro-bind` mounts
    - Preserved existing writable-root and protected-subpath behavior
    (`.git`, `.codex`, etc.).
    
    `ReadOnlyAccess::Restricted` was already modeled in protocol, but Linux
    bwrap still returned `UnsupportedOperation` for restricted read access.
    This closes that gap for the active Linux filesystem backend.
    
    
    ## Notes
    Legacy Linux Landlock fallback still fail-closes for restricted read
    access (unchanged).
  • Revert "Ensure shell command skills trigger approval (#12697)" (#12721)
    This reverts commit daf0f03ac8.
    
    # External (non-OpenAI) Pull Request Requirements
    
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    If your PR conforms to our contribution guidelines, replace this text
    with a detailed and high quality description of your changes.
    
    Include a link to a bug report or enhancement request.
  • Ensure shell command skills trigger approval (#12697)
    Summary
    - detect skill-invoking shell commands based on the original command
    string, request approvals when needed, and cache positive decisions per
    session
    - keep implicit skill invocation emitted after approval and keep skill
    approval decline messaging centralized to the shell handler
    - expand and adjust skill approval tests to cover shell-based skill
    scripts while matching the new detection expectations
    
    Testing
    - Not run (not requested)
  • feat(linux-sandbox): implement proxy-only egress via TCP-UDS-TCP bridge (#11293)
    ## Summary
    - Implement Linux proxy-only routing in `codex-rs/linux-sandbox` with a
    two-stage bridge: host namespace `loopback TCP proxy endpoint -> UDS`,
    then bwrap netns `loopback TCP listener -> host UDS`.
    - Add hidden `--proxy-route-spec` plumbing for outer-to-inner stage
    handoff.
    - Fail closed in proxy mode when no valid loopback proxy endpoints can
    be routed.
    - Introduce explicit network seccomp modes: `Restricted` (legacy
    restricted networking) and `ProxyRouted` (allow INET/INET6 for routed
    proxy access, deny `AF_UNIX` and `socketpair`).
    - Enforce that proxy bridge/routing is bwrap-only by validating
    `--apply-seccomp-then-exec` requires `--use-bwrap-sandbox`.
    - Keep landlock-only flows unchanged (no proxy bridge behavior outside
    bwrap).
    
    ---------
    
    Co-authored-by: Codex <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>
  • chore: remove codex-core public protocol/shell re-exports (#12432)
    ## Why
    
    `codex-rs/core/src/lib.rs` re-exported a broad set of types and modules
    from `codex-protocol` and `codex-shell-command`. That made it easy for
    workspace crates to import those APIs through `codex-core`, which in
    turn hides dependency edges and makes it harder to reduce compile-time
    coupling over time.
    
    This change removes those public re-exports so call sites must import
    from the source crates directly. Even when a crate still depends on
    `codex-core` today, this makes dependency boundaries explicit and
    unblocks future work to drop `codex-core` dependencies where possible.
    
    ## What Changed
    
    - Removed public re-exports from `codex-rs/core/src/lib.rs` for:
    - `codex_protocol::protocol` and related protocol/model types (including
    `InitialHistory`)
      - `codex_protocol::config_types` (`protocol_config_types`)
    - `codex_shell_command::{bash, is_dangerous_command, is_safe_command,
    parse_command, powershell}`
    - Migrated workspace Rust call sites to import directly from:
      - `codex_protocol::protocol`
      - `codex_protocol::config_types`
      - `codex_protocol::models`
      - `codex_shell_command`
    - Added explicit `Cargo.toml` dependencies (`codex-protocol` /
    `codex-shell-command`) in crates that now import those crates directly.
    - Kept `codex-core` internal modules compiling by using `pub(crate)`
    aliases in `core/src/lib.rs` (internal-only, not part of the public
    API).
    - Updated the two utility crates that can already drop a `codex-core`
    dependency edge entirely:
      - `codex-utils-approval-presets`
      - `codex-utils-cli`
    
    ## Verification
    
    - `cargo test -p codex-utils-approval-presets`
    - `cargo test -p codex-utils-cli`
    - `cargo check --workspace --all-targets`
    - `just clippy`
  • Refactor network approvals to host/protocol/port scope (#12140)
    ## Summary
    Simplify network approvals by removing per-attempt proxy correlation and
    moving to session-level approval dedupe keyed by (host, protocol, port).
    Instead of encoding attempt IDs into proxy credentials/URLs, we now
    treat approvals as a destination policy decision.
    
    - Concurrent calls to the same destination share one approval prompt.
    - Different destinations (or same host on different ports) get separate
    prompts.
    - Allow once approves the current queued request group only.
    - Allow for session caches that (host, protocol, port) and auto-allows
    future matching requests.
    - Never policy continues to deny without prompting.
    
    Example:
    - 3 calls: 
      - a.com (line 443)
      - b.com (line 443)
      - a.com (line 443)
    => 2 prompts total (a, b), second a waits on the first decision.
    - a.com:80 is treated separately from a.com line 443
    
    ## Testing
    - `just fmt` (in `codex-rs`)
    - `cargo test -p codex-core tools::network_approval::tests`
    - `cargo test -p codex-core` (unit tests pass; existing
    integration-suite failures remain in this environment)
  • fix(linux-sandbox): mount /dev in bwrap sandbox (#12081)
    ## Summary
    - Updates the Linux bubblewrap sandbox args to mount a minimal `/dev`
    using `--dev /dev` instead of only binding `/dev/null`. tools needing
    entropy (git, crypto libs, etc.) can fail.
    
    - Changed mount order so `--dev /dev` is added before writable-root
    `--bind` mounts, preserving writable `/dev/*` submounts like `/dev/shm`
    
    ## Why
    Fixes sandboxed command failures when reading `/dev/urandom` (and
    similar standard device-node access).
    
    
    Fixes https://github.com/openai/codex/issues/12056
  • feat(core): add structured network approval plumbing and policy decision model (#11672)
    ### Description
    #### Summary
    Introduces the core plumbing required for structured network approvals
    
    #### What changed
    - Added structured network policy decision modeling in core.
    - Added approval payload/context types needed for network approval
    semantics.
    - Wired shell/unified-exec runtime plumbing to consume structured
    decisions.
    - Updated related core error/event surfaces for structured handling.
    - Updated protocol plumbing used by core approval flow.
    - Included small CLI debug sandbox compatibility updates needed by this
    layer.
    
    #### Why
    establishes the minimal backend foundation for network approvals without
    yet changing high-level orchestration or TUI behavior.
    
    #### Notes
    - Behavior remains constrained by existing requirements/config gating.
    - Follow-up PRs in the stack handle orchestration, UX, and app-server
    integration.
    
    ---------
    
    Co-authored-by: Codex <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>
  • build(linux-sandbox): always compile vendored bubblewrap on Linux; remove CODEX_BWRAP_ENABLE_FFI (#11498)
    ## Summary
    This PR removes the temporary `CODEX_BWRAP_ENABLE_FFI` flag and makes
    Linux builds always compile vendored bubblewrap support for
    `codex-linux-sandbox`.
    
    ## Changes
    - Removed `CODEX_BWRAP_ENABLE_FFI` gating from
    `codex-rs/linux-sandbox/build.rs`.
    - Linux builds now fail fast if vendored bubblewrap compilation fails
    (instead of warning and continuing).
    - Updated fallback/help text in
    `codex-rs/linux-sandbox/src/vendored_bwrap.rs` to remove references to
    `CODEX_BWRAP_ENABLE_FFI`.
    - Removed `CODEX_BWRAP_ENABLE_FFI` env wiring from:
      - `.github/workflows/rust-ci.yml`
      - `.github/workflows/bazel.yml`
      - `.github/workflows/rust-release.yml`
    
    ---------
    
    Co-authored-by: David Zbarsky <zbarsky@openai.com>
  • feat: make sandbox read access configurable with ReadOnlyAccess (#11387)
    `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.
  • feat(sandbox): enforce proxy-aware network routing in sandbox (#11113)
    ## Summary
    - expand proxy env injection to cover common tool env vars
    (`HTTP_PROXY`/`HTTPS_PROXY`/`ALL_PROXY`/`NO_PROXY` families +
    tool-specific variants)
    - harden macOS Seatbelt network policy generation to route through
    inferred loopback proxy endpoints and fail closed when proxy env is
    malformed
    - thread proxy-aware Linux sandbox flags and add minimal bwrap netns
    isolation hook for restricted non-proxy runs
    - add/refresh tests for proxy env wiring, Seatbelt policy generation,
    and Linux sandbox argument wiring
  • deflake linux-sandbox NoNewPrivs timeout (#11245)
    Deflake `codex-linux-sandbox::all
    suite::landlock::test_no_new_privs_is_enabled`.
    
    CI has intermittently failed with `Sandbox(Timeout)` (exit 124) because
    the sandboxed
    `grep '^NoNewPrivs:' /proc/self/status` can run close to the short
    timeout budget.
    
    This updates only this test to use `LONG_TIMEOUT_MS`, which removes the
    near-threshold timeout
    behavior while keeping the rest of the suite unchanged.
    
    Refs (previous failures):
    - PR:
    https://github.com/openai/codex/actions/runs/21836764823/job/63009902779
    - PR:
    https://github.com/openai/codex/actions/runs/21837427251/job/63012470353
    - main:
    https://github.com/openai/codex/actions/runs/21830746538/job/62988079964
    
    Validation:
    - Local: `cd codex-rs && cargo test -p codex-linux-sandbox` (non-Linux
    runs 0 tests)
  • feat: include NetworkConfig through ExecParams (#11105)
    This PR adds the following field to `Config`:
    
    ```rust
    pub network: Option<NetworkProxy>,
    ```
    
    Though for the moment, it will always be initialized as `None` (this
    will be addressed in a subsequent PR).
    
    This PR does the work to thread `network` through to `execute_exec_env()`, `process_exec_tool_call()`, and `UnifiedExecRuntime.run()` to ensure it is available whenever we span a process.
  • fix(linux-sandbox): block io_uring syscalls in no-network seccomp policy (#10814)
    ## Summary
    
    - Add seccomp deny rules for `io_uring` syscalls in the Linux sandbox
    network policy.
    - Specifically deny:
      - `SYS_io_uring_setup`
      - `SYS_io_uring_enter`
      - `SYS_io_uring_register`
  • feat(linux-sandbox): add bwrap support (#9938)
    ## 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.
  • Inject CODEX_THREAD_ID into the terminal environment (#10096)
    Inject CODEX_THREAD_ID (when applicable) into the terminal environment
    so that the agent (and skills) can refer to the current thread / session
    ID.
    
    Discussion:
    https://openai.slack.com/archives/C095U48JNL9/p1769542492067109
  • feat(linux-sandbox): vendor bubblewrap and wire it with FFI (#10413)
    ## Summary
    
    Vendor Bubblewrap into the repo and add minimal build plumbing in
    `codex-linux-sandbox` to compile/link it.
    
    ## Why
    
    We want to move Linux sandboxing toward Bubblewrap, but in a safe
    two-step rollout:
    1) vendoring/build setup (this PR),  
    2) runtime integration (follow-up PR).
    
    ## Included
    
    - Add `codex-rs/vendor/bubblewrap` sources.
    - Add build-time FFI path in `codex-rs/linux-sandbox`.
    - Update `build.rs` rerun tracking for vendored files.
    - Small vendored compile warning fix (`sockaddr_nl` full init).
    
    follow up in https://github.com/openai/codex/pull/9938
  • remove sandbox globals. (#9797)
    Threads sandbox updates through OverrideTurnContext for active turn
    Passes computed sandbox type into safety/exec
  • revert: remove pre-Landlock bind mounts apply (#9300)
    **Description**
    
    This removes the pre‑Landlock read‑only bind‑mount step from the Linux
    sandbox so filesystem restrictions rely solely on Landlock again.
    `mounts.rs` is kept in place but left unused. The linux‑sandbox README
    is updated to match the new behavior and manual test expectations.
  • fix: fallback to Landlock-only when user namespaces unavailable and set PR_SET_NO_NEW_PRIVS early (#9250)
    fixes https://github.com/openai/codex/issues/9236
    
    ### Motivation
    - Prevent sandbox setup from failing when unprivileged user namespaces
    are denied so Landlock-only protections can still be applied.
    - Ensure `PR_SET_NO_NEW_PRIVS` is set before installing seccomp and
    Landlock restrictions to avoid kernel `EPERM`/`LandlockRestrict`
    ordering issues.
    
    ### Description
    - Add `is_permission_denied` helper that detects `EPERM` /
    `PermissionDenied` from `CodexErr` to drive fallback logic.
    - In `apply_read_only_mounts` skip read-only bind-mount setup and return
    `Ok(())` when `unshare_user_and_mount_namespaces()` fails with
    permission-denied so Landlock rules can still be installed.
    - Add `set_no_new_privs()` and call it from
    `apply_sandbox_policy_to_current_thread` before installing seccomp
    filters and Landlock rules when disk or network access is restricted.
  • fix: correct linux sandbox uid/gid mapping after unshare (#9234)
    fixes https://github.com/openai/codex/issues/9233
    ## Summary
    - capture effective uid/gid before unshare for user namespace maps
    - pass captured ids into uid/gid map writer
    
    ## Testing
    - just fmt
    - just fix -p codex-linux-sandbox
    - cargo test -p codex-linux-sandbox
  • feat: add support for read-only bind mounts in the linux sandbox (#9112)
    ### Motivation
    
    - Landlock alone cannot prevent writes to sensitive in-repo files like
    `.git/` when the repo root is writable, so explicit mount restrictions
    are required for those paths.
    - The sandbox must set up any mounts before calling Landlock so Landlock
    can still be applied afterwards and the two mechanisms compose
    correctly.
    
    ### Description
    
    - Add a new `linux-sandbox` helper `apply_read_only_mounts` in
    `linux-sandbox/src/mounts.rs` that: unshares namespaces, maps uids/gids
    when required, makes mounts private, bind-mounts targets, and remounts
    them read-only.
    - Wire the mount step into the sandbox flow by calling
    `apply_read_only_mounts(...)` before network/seccomp and before applying
    Landlock rules in `linux-sandbox/src/landlock.rs`.
  • feat: add support for building with Bazel (#8875)
    This PR configures Codex CLI so it can be built with
    [Bazel](https://bazel.build) in addition to Cargo. The `.bazelrc`
    includes configuration so that remote builds can be done using
    [BuildBuddy](https://www.buildbuddy.io).
    
    If you are familiar with Bazel, things should work as you expect, e.g.,
    run `bazel test //... --keep-going` to run all the tests in the repo,
    but we have also added some new aliases in the `justfile` for
    convenience:
    
    - `just bazel-test` to run tests locally
    - `just bazel-remote-test` to run tests remotely (currently, the remote
    build is for x86_64 Linux regardless of your host platform). Note we are
    currently seeing the following test failures in the remote build, so we
    still need to figure out what is happening here:
    
    ```
    failures:
        suite::compact::manual_compact_twice_preserves_latest_user_messages
        suite::compact_resume_fork::compact_resume_after_second_compaction_preserves_history
        suite::compact_resume_fork::compact_resume_and_fork_preserve_model_history_view
    ```
    
    - `just build-for-release` to build release binaries for all
    platforms/architectures remotely
    
    To setup remote execution:
    - [Create a buildbuddy account](https://app.buildbuddy.io/) (OpenAI
    employees should also request org access at
    https://openai.buildbuddy.io/join/ with their `@openai.com` email
    address.)
    - [Copy your API key](https://app.buildbuddy.io/docs/setup/) to
    `~/.bazelrc` (add the line `build
    --remote_header=x-buildbuddy-api-key=YOUR_KEY`)
    - Use `--config=remote` in your `bazel` invocations (or add `common
    --config=remote` to your `~/.bazelrc`, or use the `just` commands)
    
    ## CI
    
    In terms of CI, this PR introduces `.github/workflows/bazel.yml`, which
    uses Bazel to run the tests _locally_ on Mac and Linux GitHub runners
    (we are working on supporting Windows, but that is not ready yet). Note
    that the failures we are seeing in `just bazel-remote-test` do not occur
    on these GitHub CI jobs, so everything in `.github/workflows/bazel.yml`
    is green right now.
    
    The `bazel.yml` uses extra config in `.github/workflows/ci.bazelrc` so
    that macOS CI jobs build _remotely_ on Linux hosts (using the
    `docker://docker.io/mbolin491/codex-bazel` Docker image declared in the
    root `BUILD.bazel`) using cross-compilation to build the macOS
    artifacts. Then these artifacts are downloaded locally to GitHub's macOS
    runner so the tests can be executed natively. This is the relevant
    config that enables this:
    
    ```
    common:macos --config=remote
    common:macos --strategy=remote
    common:macos --strategy=TestRunner=darwin-sandbox,local
    ```
    
    Because of the remote caching benefits we get from BuildBuddy, these new
    CI jobs can be extremely fast! For example, consider these two jobs that
    ran all the tests on Linux x86_64:
    
    - Bazel 1m37s
    https://github.com/openai/codex/actions/runs/20861063212/job/59940545209?pr=8875
    - Cargo 9m20s
    https://github.com/openai/codex/actions/runs/20861063192/job/59940559592?pr=8875
    
    For now, we will continue to run both the Bazel and Cargo jobs for PRs,
    but once we add support for Windows and running Clippy, we should be
    able to cutover to using Bazel exclusively for PRs, which should still
    speed things up considerably. We will probably continue to run the Cargo
    jobs post-merge for commits that land on `main` as a sanity check.
    
    Release builds will also continue to be done by Cargo for now.
    
    Earlier attempt at this PR: https://github.com/openai/codex/pull/8832
    Earlier attempt to add support for Buck2, now abandoned:
    https://github.com/openai/codex/pull/8504
    
    ---------
    
    Co-authored-by: David Zbarsky <dzbarsky@gmail.com>
    Co-authored-by: Michael Bolin <mbolin@openai.com>
  • fix: introduce AbsolutePathBuf as part of sandbox config (#7856)
    Changes the `writable_roots` field of the `WorkspaceWrite` variant of
    the `SandboxPolicy` enum from `Vec<PathBuf>` to `Vec<AbsolutePathBuf>`.
    This is helpful because now callers can be sure the value is an absolute
    path rather than a relative one. (Though when using an absolute path in
    a Seatbelt config policy, we still have to _canonicalize_ it first.)
    
    Because `writable_roots` can be read from a config file, it is important
    that we are able to resolve relative paths properly using the parent
    folder of the config file as the base path.
  • refactoring with_escalated_permissions to use SandboxPermissions instead (#7750)
    helpful in the future if we want more granularity for requesting
    escalated permissions:
    e.g when running in readonly sandbox, model can request to escalate to a
    sandbox that allows writes
  • fix: allow sendmsg(2) and recvmsg(2) syscalls in our Linux sandbox (#7779)
    This changes our default Landlock policy to allow `sendmsg(2)` and
    `recvmsg(2)` syscalls. We believe these were originally denied out of an
    abundance of caution, but given that `send(2)` nor `recv(2)` are allowed
    today [which provide comparable capability to the `*msg` equivalents],
    we do not believe allowing them grants any privileges beyond what we
    already allow.
    
    Rather than using the syscall as the security boundary, preventing
    access to the potentially hazardous file descriptor in the first place
    seems like the right layer of defense.
    
    In particular, this makes it possible for `shell-tool-mcp` to run on
    Linux when using a read-only sandbox for the Bash process, as
    demonstrated by `accept_elicitation_for_prompt_rule()` now succeeding in
    CI.
  • chore: add cargo-deny configuration (#7119)
    - add GitHub workflow running cargo-deny on push/PR
    - document cargo-deny allowlist with workspace-dep notes and advisory
    ignores
    - align workspace crates to inherit version/edition/license for
    consistent checks
  • refactor: inline sandbox type lookup in process_exec_tool_call (#7122)
    `process_exec_tool_call()` was taking `SandboxType` as a param, but in
    practice, the only place it was constructed was in
    `codex_message_processor.rs` where it was derived from the other
    `sandbox_policy` param, so this PR inlines the logic that decides the
    `SandboxType` into `process_exec_tool_call()`.
    
    
    
    ---
    [//]: # (BEGIN SAPLING FOOTER)
    Stack created with [Sapling](https://sapling-scm.com). Best reviewed
    with [ReviewStack](https://reviewstack.dev/openai/codex/pull/7122).
    * #7112
    * __->__ #7122
  • feat: update process_exec_tool_call() to take a cancellation token (#6972)
    This updates `ExecParams` so that instead of taking `timeout_ms:
    Option<u64>`, it now takes a more general cancellation mechanism,
    `ExecExpiration`, which is an enum that includes a
    `Cancellation(tokio_util::sync::CancellationToken)` variant.
    
    If the cancellation token is fired, then `process_exec_tool_call()`
    returns in the same way as if a timeout was exceeded.
    
    This is necessary so that in #6973, we can manage the timeout logic
    external to the `process_exec_tool_call()` because we want to "suspend"
    the timeout when an elicitation from a human user is pending.
    
    
    
    
    
    
    
    
    ---
    [//]: # (BEGIN SAPLING FOOTER)
    Stack created with [Sapling](https://sapling-scm.com). Best reviewed
    with [ReviewStack](https://reviewstack.dev/openai/codex/pull/6972).
    * #7005
    * #6973
    * __->__ #6972
  • chore: rework tools execution workflow (#5278)
    Re-work the tool execution flow. Read `orchestrator.rs` to understand
    the structure
  • chore: clippy on redundant closure (#4058)
    Add redundant closure clippy rules and let Codex fix it by minimising
    FQP
  • chore: unify cargo versions (#4044)
    Unify cargo versions at root
  • fix: ensure cwd for conversation and sandbox are separate concerns (#3874)
    Previous to this PR, both of these functions take a single `cwd`:
    
    
    https://github.com/openai/codex/blob/71038381aa0f51aa62e1a2bcc7cbf26a05b141f3/codex-rs/core/src/seatbelt.rs#L19-L25
    
    
    https://github.com/openai/codex/blob/71038381aa0f51aa62e1a2bcc7cbf26a05b141f3/codex-rs/core/src/landlock.rs#L16-L23
    
    whereas `cwd` and `sandbox_cwd` should be set independently (fixed in
    this PR).
    
    Added `sandbox_distinguishes_command_and_policy_cwds()` to
    `codex-rs/exec/tests/suite/sandbox.rs` to verify this.