There is an edge case where a directory is not readable by the sandbox.
In practice, we've seen very little of it, but it can happen so this
slash command unlocks users when it does.
Future idea is to make this a tool that the agent knows about so it can
be more integrated.
`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.
1. Move Windows Sandbox NUX to right after trust directory screen
2. Don't offer read-only as an option in Sandbox NUX.
Elevated/Legacy/Quit
3. Don't allow new untrusted directories. It's trust or quit
4. move experimental sandbox features to `[windows]
sandbox="elevated|unelevatd"`
5. Copy tweaks = elevated -> default, non-elevated -> non-admin
calculated a hashed user ID from either auth user id or API key
Also correctly populates OS.
These will make our metrics more useful and powerful for analysis.
Today, there is a single capability SID that allows the sandbox to write
to
* workspace (cwd)
* tmp directories if enabled
* additional writable roots
This change splits those up, so that each workspace has its own
capability SID, while tmp and additional roots, which are
installation-wide, are still governed by the "generic" capability SID
This isolates workspaces from each other in terms of sandbox write
access.
Also allows us to protect <cwd>/.codex when codex runs in a specific
<cwd>
This fixes a bug where the elevated sandbox setup encrypts sandbox user
passwords as an admin user, but normal command execution attempts to
decrypt them as a different user.
Machine scope allows all users to encyrpt/decrypt
this PR also moves the encrypted file to a different location
.codex/.sandbox-secrets which the sandbox users cannot read.
Elevated Sandbox NUX:
* prompt for elevated sandbox setup when agent mode is selected (via
/approvals or at startup)
* prompt for degraded sandbox if elevated setup is declined or fails
* introduce /elevate-sandbox command to upgrade from degraded
experience.
The elevated sandbox creates two new Windows users - CodexSandboxOffline
and CodexSandboxOnline. This is necessary, so this PR does all that it
can to "hide" those users. It uses the registry plus directory flags (on
their home directories) to get them to show up as little as possible.
The elevated setup synchronously applies read/write ACLs to any
workspace roots.
However, until we apply *read* permission to the full path, powershell
cannot use some roots as a cwd as it needs access to all parts of the
path in order to apply it as the working directory for a command.
The solution is, while the async read-ACL part of setup is running, use
a "junction" that lives in C:\Users\CodexSandbox{Offline|Online} that
points to the cwd.
Once the read ACLs are applied, we stop using the junction.
-----
this PR also removes some dead code and overly-verbose logging, and has
some light refactoring to the ACL-related functions
## Description
Introduced `ExternalSandbox` policy to cover use case when sandbox
defined by outside environment, effectively it translates to
`SandboxMode#DangerFullAccess` for file system (since sandbox configured
on container level) and configurable `network_access` (either Restricted
or Enabled by outside environment).
as example you can configure `ExternalSandbox` policy as part of
`sendUserTurn` v1 app_server API:
```
{
"conversationId": <id>,
"cwd": <cwd>,
"approvalPolicy": "never",
"sandboxPolicy": {
"type": ""external-sandbox",
"network_access": "enabled"/"restricted"
},
"model": <model>,
"effort": <effort>,
....
}
```
- Batch read ACL creation for online/offline sandbox user
- creates a new ACL helper process that is long-lived and runs in the
background
- uses a mutex so that only one helper process is running at a time.
a few fixes based on testing feedback:
* ensure cap_sid file is always written by elevated setup.
* always log to same file whether using elevated sandbox or not
* process potentially slow ACE write operations in parallel
* dedupe write roots so we don't double process any
* don't try to create read/write ACEs on the same directories, due to
race condition
clean up the code for scanning for world writable directories
One path (selecting a sandbox mode from /approvals) was using an
incorrect method that did not use the new method of creating deny aces
to prevent writing to those directories. Now all paths are the same.
Our Restricted Token contains 3 SIDs (Logon, Everyone, {WorkspaceWrite
Capability || ReadOnly Capability})
because it must include Everyone, that left us vulnerable to directories
that allow writes to Everyone. Even though those directories do not have
ACEs that enable our capability SIDs to write to them, they could still
be written to even in ReadOnly mode, or even in WorkspaceWrite mode if
they are outside of a writable root.
A solution to this is to explicitly add *Deny* ACEs to these
directories, always for the ReadOnly Capability SID, and for the
WorkspaceWrite SID if the directory is outside of a workspace root.
Under a restricted token, Windows always checks Deny ACEs before Allow
ACEs so even though our restricted token would allow a write to these
directories due to the Everyone SID, it fails first because of the Deny
ACE on the capability SID
The `cap_sid` file contains the IDs of the two custom SIDs that the
Windows sandbox creates/manages to implement read-only and
workspace-write sandbox policies.
It previously lived in `<cwd>/.codex` which means that the sandbox could
write to it, which could degrade the efficacy of the sandbox. This
change moves it to `~/.codex/` (or wherever `CODEX_HOME` points to) so
that it is outside the workspace.
3 improvements:
1. show up to 3 actual paths that are world-writable
2. do the scan/warning for Read-Only mode too, because it also applies
there
3. remove the "Cancel" option since it doesn't always apply (like on
startup)
1. scan many more directories since it's much faster than the original
implementation
2. limit overall scan time to 2s
3. skip some directories that are noisy - ApplicationData, Installer,
etc.
- Added the new codex-windows-sandbox crate that builds both a library
entry point (run_windows_sandbox_capture) and a CLI executable to launch
commands inside a Windows restricted-token sandbox, including ACL
management, capability SID provisioning, network lockdown, and output
capture
(windows-sandbox-rs/src/lib.rs:167, windows-sandbox-rs/src/main.rs:54).
- Introduced the experimental WindowsSandbox feature flag and wiring so
Windows builds can opt into the sandbox:
SandboxType::WindowsRestrictedToken, the in-process execution path, and
platform sandbox selection now honor the flag (core/src/features.rs:47,
core/src/config.rs:1224, core/src/safety.rs:19,
core/src/sandboxing/mod.rs:69, core/src/exec.rs:79,
core/src/exec.rs:172).
- Updated workspace metadata to include the new crate and its
Windows-specific dependencies so the core crate can link against it
(codex-rs/
Cargo.toml:91, core/Cargo.toml:86).
- Added a PowerShell bootstrap script that installs the Windows
toolchain, required CLI utilities, and builds the workspace to ease
development
on the platform (scripts/setup-windows.ps1:1).
- Landed a Python smoke-test suite that exercises
read-only/workspace-write policies, ACL behavior, and network denial for
the Windows sandbox
binary (windows-sandbox-rs/sandbox_smoketests.py:1).
