Windows Sandbox - Alpha version (#4905)

- 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).

codex-rs/cli/src/debug_sandbox.rs

@@ -11,6 +11,7 @@ use codex_protocol::config_types::SandboxMode;
 
 use crate::LandlockCommand;
 use crate::SeatbeltCommand;
+use crate::WindowsCommand;
 use crate::exit_status::handle_exit_status;
 
 pub async fn run_command_under_seatbelt(
@@ -51,9 +52,29 @@ pub async fn run_command_under_landlock(
     .await
 }
 
+pub async fn run_command_under_windows(
+    command: WindowsCommand,
+    codex_linux_sandbox_exe: Option<PathBuf>,
+) -> anyhow::Result<()> {
+    let WindowsCommand {
+        full_auto,
+        config_overrides,
+        command,
+    } = command;
+    run_command_under_sandbox(
+        full_auto,
+        command,
+        config_overrides,
+        codex_linux_sandbox_exe,
+        SandboxType::Windows,
+    )
+    .await
+}
+
 enum SandboxType {
     Seatbelt,
     Landlock,
+    Windows,
 }
 
 async fn run_command_under_sandbox(
@@ -87,6 +108,63 @@ async fn run_command_under_sandbox(
     let stdio_policy = StdioPolicy::Inherit;
     let env = create_env(&config.shell_environment_policy);
 
+    // Special-case Windows sandbox: execute and exit the process to emulate inherited stdio.
+    if let SandboxType::Windows = sandbox_type {
+        #[cfg(target_os = "windows")]
+        {
+            use codex_windows_sandbox::run_windows_sandbox_capture;
+
+            let policy_str = match &config.sandbox_policy {
+                codex_core::protocol::SandboxPolicy::DangerFullAccess => "workspace-write",
+                codex_core::protocol::SandboxPolicy::ReadOnly => "read-only",
+                codex_core::protocol::SandboxPolicy::WorkspaceWrite { .. } => "workspace-write",
+            };
+
+            let sandbox_cwd = sandbox_policy_cwd.clone();
+            let cwd_clone = cwd.clone();
+            let env_map = env.clone();
+            let command_vec = command.clone();
+            let res = tokio::task::spawn_blocking(move || {
+                run_windows_sandbox_capture(
+                    policy_str,
+                    &sandbox_cwd,
+                    command_vec,
+                    &cwd_clone,
+                    env_map,
+                    None,
+                )
+            })
+            .await;
+
+            let capture = match res {
+                Ok(Ok(v)) => v,
+                Ok(Err(err)) => {
+                    eprintln!("windows sandbox failed: {err}");
+                    std::process::exit(1);
+                }
+                Err(join_err) => {
+                    eprintln!("windows sandbox join error: {join_err}");
+                    std::process::exit(1);
+                }
+            };
+
+            if !capture.stdout.is_empty() {
+                use std::io::Write;
+                let _ = std::io::stdout().write_all(&capture.stdout);
+            }
+            if !capture.stderr.is_empty() {
+                use std::io::Write;
+                let _ = std::io::stderr().write_all(&capture.stderr);
+            }
+
+            std::process::exit(capture.exit_code);
+        }
+        #[cfg(not(target_os = "windows"))]
+        {
+            anyhow::bail!("Windows sandbox is only available on Windows");
+        }
+    }
+
     let mut child = match sandbox_type {
         SandboxType::Seatbelt => {
             spawn_command_under_seatbelt(
@@ -115,6 +193,9 @@ async fn run_command_under_sandbox(
             )
             .await?
         }
+        SandboxType::Windows => {
+            unreachable!("Windows sandbox should have been handled above");
+        }
     };
     let status = child.wait().await?;