## Why
MXC read-only volume-root grants already provide recursive access, so enumerating their children is unnecessary.
## What changed
Expand only writable volume roots into grants for their immediate children. Document that read-only grants recurse, while new children created during a running command are not implicitly writable.
## Testing
Update policy tests to verify that only writable roots expand their children and that narrowing one volume preserves the other volume's grants.
GitOrigin-RevId: a7c7348b2f75bc7258fb1f130cfa4d9660e2faa6
Default read access on Windows now excludes network shares unless they contain
the policy or command working directory. Skip object-identity probes and
implicit read enumeration for unrelated shares while preserving explicit
read/write grants.
GitOrigin-RevId: 869bacd578989f5348a449277ffbea795494f487
## Why
MXC's `normalize_object_conflicts` can reject otherwise usable Windows policies when a network share does not support `FileIdInfo` or a protected deny path cannot be opened for metadata.
## What changed
Remove object-conflict normalization before and after volume-root expansion. Send explicit path grants directly to BaseContainer, which enforces path and symlink/junction alias precedence.
Document the resulting limitations:
- Hard-link names retain independent permissions, so an allowed name can access the same file through a less restrictive grant.
- Volume roots expand using their declared access without first reconciling aliases. A writable root can therefore generate more-specific writable grants that override a read-only root alias.
GitOrigin-RevId: de0b2d7b5b98eaa358a97156c02e9f7f85860335
## Why
Windows MXC needs valid host startup variables, while an empty child environment must remain empty for the SDK to select Windows user-profile defaults.
## What changed
- Replace caller overrides of `SystemDrive` and `LOCALAPPDATA` case-insensitively with nonempty Unicode host values, failing before launch if either is unavailable.
- Track whether the original child environment was empty, ignoring launcher transport keys. Supply host `SystemRoot` for launcher bootstrap in that case, then clear the bootstrap environment before the SDK selects defaults.
## Testing
Extend transport tests to cover host-value replacement and preservation of empty child environments. Strengthen the PowerShell fallback RPC test to require `SystemDrive`, `LOCALAPPDATA`, `USERPROFILE`, and `PATH` in the child.
GitOrigin-RevId: a097e1079069ef897ebb5ba5e63546328c5faeaa
## Why
PSEC API symbols can be present on transitional Windows builds where MXC is not enabled. Availability detection needs to verify that a native process security environment can actually be created.
## What changed
- Replace `mxc-sdk` with pinned `appcontainer_common`, `learning_mode_windows`, and `wxc_common` dependencies, and update Cargo and Bazel dependency metadata.
- Use MXC's cached create/close probe for `is_available()` and query native deny-path support through `SecurityEnvironmentApi` before launching requests with denied paths.
- Adapt request construction and the existing policy test to the vector-based environment field, and update the sandbox documentation.
GitOrigin-RevId: e8cc6a35d46884d0a069b747d33e711512ec1596
## What changed
- Replace the separate MXC crates with the pinned `mxc-sdk` 1.0.0 dependency and update Cargo and Bazel lockfiles.
- Use the cached PSEC API-set check for availability and the SDK's native deny-path capability check before launch. Native creation and request-specific capabilities are validated at launch.
- Map empty environments to `None` to retain Windows user-profile defaults, while keeping nonempty environments explicit. Document the SDK's `SystemRoot` and `LOCALAPPDATA` requirements.
- Configure Bazel's LLVM resource compiler for Windows GNU builds, document Cargo's `RC_PATH` requirement, and add `libproc` and `libsandbox` to the macOS SDK libraries.
## Testing
Update the request-building test to verify that nonempty environments remain explicit and empty environments become `None`.
GitOrigin-RevId: f3ccbb92ceaa71f16c5d6cb185a7602a5bb8da53
## What changed
Add the default-off `features.prefer_mxc` flag to select MXC for local Windows execution when native support is available and effective network settings do not explicitly forbid local binding. Otherwise, retain the configured backend and legacy setup behavior.
Resolve the preference during config loading and use the effective local backend for execution, network proxy setup, sandbox diagnostics, and `windowsSandbox/readiness`. Preserve the configured backend for remote executors and `config/read`. Explicit `windows.sandbox = "mxc"` remains strict, and command failures do not trigger backend fallback.
## Testing
Add coverage for preference resolution, startup readiness without rewriting configuration, local and remote backend selection across environment updates and child threads, and workspace-write permission context in an agent turn.
GitOrigin-RevId: b51178f0371d38ebb58e41af54a068fca67fa316
## Why
MXC's native host-loopback access is bidirectional, so it cannot enforce `allow_local_binding = false`. Treating an omitted setting as `false` prevents managed networking from working with the default configuration.
## What changed
- Preserve an omitted `allow_local_binding` until the executor's sandbox policy is known. Default to `true` for Windows MXC and `false` elsewhere, including remote execution.
- Reject an effective `false` for MXC managed networking after applying policy restrictions, without enabling disabled networking.
- Use the executor's resolved value for remote network approval decisions while preserving explicit controller restrictions.
- Document that local binding permits local servers and direct host-loopback connections and skips additional private-network destination checks; proxy domain rules still apply.
## Testing
Add coverage for per-executor defaults, explicit values, MXC rejection of `false`, and remote network review cleanup with the resolved policy.
GitOrigin-RevId: 0fa7c1eaec68bebada2b8f7af45688315eea70a9
## What changed
- Add explicit MXC backend selection and carry its identity through exec-server process reporting and sandbox violation classification.
- Launch MXC through the Codex executable with the effective permission profile and command environment.
- Reject exec-server MXC requests when native MXC is unavailable or when they request a TTY, an `arg0` override, or managed networking. Reject private desktop isolation during MXC preparation.
- Allow an explicitly empty child environment and avoid exposing request payload values in launcher decode errors.
## Testing
Add coverage for sandbox selection and unsupported-request rejection, plus Windows RPC tests for stdin writes and temporary-directory permissions derived from the command environment. Native MXC tests skip when MXC is unavailable.
GitOrigin-RevId: 3626ff0f9ad7f9b812ce09b68c31ea9a5a9c72b1
## What changed
- Dispatch `--__codex-windows-mxc` before normal CLI parsing, launch the decoded request, and propagate the child exit code.
- Build the native request from the helper's environment and working directory, discovered Windows platform directories, and volume roots, including UNC working-directory roots. Reject non-Unicode environment values and empty child environments.
- Allow Win32k calls and desktop handles needed for PowerShell startup while retaining clipboard, input-injection, and desktop/system-control restrictions.
- Keep policy, transport, and native launch internals private, and report an explicit error when the helper is invoked outside Windows.
## Testing
Add a wrapper regression test covering exact argument preservation, Windows quoting, separate policy and command working directories, and explicit environment forwarding.
GitOrigin-RevId: 674d0d61a3265bd517b77da9f9de2cd9fad62917
## What changed
Add `create_command_args()` to encode argv, permissions, policy cwd, and optional managed network context through the existing bounded environment transport.
For managed networking, generate a policy that allows IPv4 and IPv6 loopback while denying direct non-loopback egress and general inbound access. Require nonempty, nonzero proxy ports and reject `allow_local_binding=false` at both launcher and policy boundaries because native host-loopback access is bidirectional.
Document the MXC launch contract, platform requirements, and limitations.
## Testing
Add portable tests covering managed network transport and policy translation, plus rejection of missing proxy ports, zero ports, and unsupported local-binding restrictions at both boundaries.
GitOrigin-RevId: 8d31b98f94a2ba3769369aa50de8e53dc143bac4