feat: introduce sandbox-aware filesystem abstraction

codex-rs/core/src/bin/config_schema.rs

@@ -1,5 +1,6 @@
 use anyhow::Result;
 use clap::Parser;
+use codex_fs_ops::CODEX_CORE_FS_OPS_ARG1;
 use std::path::PathBuf;
 
 /// Generate the JSON Schema for `config.toml` and write it to `config.schema.json`.
@@ -11,6 +12,15 @@ struct Args {
 }
 
 fn main() -> Result<()> {
+    let mut args = std::env::args_os();
+    let _program_name = args.next();
+    if matches!(
+        args.next().as_deref(),
+        Some(flag) if flag == std::ffi::OsStr::new(CODEX_CORE_FS_OPS_ARG1)
+    ) {
+        return codex_fs_ops::run_from_args(args);
+    }
+
     let args = Args::parse();
     let out_path = args
         .out

codex-rs/core/src/lib.rs

@@ -112,6 +112,7 @@ pub mod default_client;
 pub mod project_doc;
 mod rollout;
 pub(crate) mod safety;
+mod sandboxed_fs;
 pub mod seatbelt;
 pub mod shell;
 pub mod shell_snapshot;

codex-rs/core/src/sandboxed_fs.rs

@@ -0,0 +1,276 @@
+use crate::codex::Session;
+use crate::codex::TurnContext;
+use crate::exec::ExecExpiration;
+use crate::sandboxing::CommandSpec;
+use crate::sandboxing::SandboxPermissions;
+use crate::sandboxing::execute_env;
+use crate::sandboxing::merge_permission_profiles;
+use crate::tools::sandboxing::SandboxAttempt;
+use crate::tools::sandboxing::SandboxablePreference;
+use base64::Engine;
+use base64::engine::general_purpose::STANDARD as BASE64_STANDARD;
+use codex_fs_ops::CODEX_CORE_FS_OPS_ARG1;
+use codex_fs_ops::FsError;
+use codex_fs_ops::FsErrorKind;
+use codex_fs_ops::FsPayload;
+use codex_fs_ops::FsResponse;
+use codex_protocol::models::PermissionProfile;
+use std::collections::HashMap;
+use std::path::Path;
+use std::path::PathBuf;
+use std::sync::Arc;
+use std::time::Duration;
+
+const SANDBOXED_FS_TIMEOUT: Duration = Duration::from_secs(30);
+
+#[derive(Debug, thiserror::Error)]
+pub(crate) enum SandboxedFsError {
+    #[error("failed to determine codex executable: {message}")]
+    ResolveExe { message: String },
+    #[error("sandboxed fs helper timed out while accessing `{path}`")]
+    TimedOut { path: PathBuf },
+    #[error("sandboxed fs helper exited with code {exit_code} while accessing `{path}`: {message}")]
+    ProcessFailed {
+        path: PathBuf,
+        exit_code: i32,
+        message: String,
+    },
+    #[error("sandboxed fs helper returned invalid output for `{path}`: {message}")]
+    InvalidResponse { path: PathBuf, message: String },
+    #[error("sandboxed fs helper could not access `{path}`: {error}")]
+    Operation { path: PathBuf, error: FsError },
+}
+
+impl SandboxedFsError {
+    pub(crate) fn operation_error_kind(&self) -> Option<&FsErrorKind> {
+        match self {
+            Self::Operation { error, .. } => Some(&error.kind),
+            _ => None,
+        }
+    }
+
+    pub(crate) fn operation_error_message(&self) -> Option<&str> {
+        match self {
+            Self::Operation { error, .. } => Some(error.message.as_str()),
+            _ => None,
+        }
+    }
+
+    #[allow(dead_code)]
+    pub(crate) fn to_io_error(&self) -> std::io::Error {
+        match self {
+            Self::Operation { error, .. } => error.to_io_error(),
+            Self::TimedOut { .. } => {
+                std::io::Error::new(std::io::ErrorKind::TimedOut, self.to_string())
+            }
+            Self::ResolveExe { .. } | Self::ProcessFailed { .. } | Self::InvalidResponse { .. } => {
+                std::io::Error::other(self.to_string())
+            }
+        }
+    }
+}
+
+pub(crate) async fn read_bytes(
+    session: &Arc<Session>,
+    turn: &Arc<TurnContext>,
+    path: &Path,
+) -> Result<Vec<u8>, SandboxedFsError> {
+    let path_buf = path.to_path_buf();
+    let payload = run_request(session, turn, "read_bytes", &path_buf).await?;
+    let FsPayload::Bytes { base64 } = payload else {
+        return Err(SandboxedFsError::InvalidResponse {
+            path: path_buf,
+            message: "expected bytes payload".to_string(),
+        });
+    };
+    BASE64_STANDARD
+        .decode(base64)
+        .map_err(|error| SandboxedFsError::InvalidResponse {
+            path: path.to_path_buf(),
+            message: format!("failed to decode base64 payload: {error}"),
+        })
+}
+
+#[allow(dead_code)]
+pub(crate) async fn read_text(
+    session: &Arc<Session>,
+    turn: &Arc<TurnContext>,
+    path: &Path,
+) -> Result<String, SandboxedFsError> {
+    let path_buf = path.to_path_buf();
+    let payload = run_request(session, turn, "read_text", &path_buf).await?;
+    let FsPayload::Text { text } = payload else {
+        return Err(SandboxedFsError::InvalidResponse {
+            path: path_buf,
+            message: "expected text payload".to_string(),
+        });
+    };
+    Ok(text)
+}
+
+async fn run_request(
+    session: &Arc<Session>,
+    turn: &Arc<TurnContext>,
+    operation: &str,
+    path: &Path,
+) -> Result<FsPayload, SandboxedFsError> {
+    let exe = resolve_codex_exe(turn)?;
+    let additional_permissions = effective_granted_permissions(session).await;
+    let sandbox_manager = crate::sandboxing::SandboxManager::new();
+    let attempt = SandboxAttempt {
+        sandbox: sandbox_manager.select_initial(
+            &turn.file_system_sandbox_policy,
+            turn.network_sandbox_policy,
+            SandboxablePreference::Auto,
+            turn.windows_sandbox_level,
+            /*has_managed_network_requirements*/ false,
+        ),
+        policy: &turn.sandbox_policy,
+        file_system_policy: &turn.file_system_sandbox_policy,
+        network_policy: turn.network_sandbox_policy,
+        enforce_managed_network: false,
+        manager: &sandbox_manager,
+        sandbox_cwd: &turn.cwd,
+        codex_linux_sandbox_exe: turn.codex_linux_sandbox_exe.as_ref(),
+        use_legacy_landlock: turn.features.use_legacy_landlock(),
+        windows_sandbox_level: turn.windows_sandbox_level,
+        windows_sandbox_private_desktop: turn.config.permissions.windows_sandbox_private_desktop,
+    };
+    let exec_request = attempt
+        .env_for(
+            CommandSpec {
+                program: exe.to_string_lossy().to_string(),
+                args: vec![
+                    CODEX_CORE_FS_OPS_ARG1.to_string(),
+                    operation.to_string(),
+                    path.to_string_lossy().to_string(),
+                ],
+                cwd: turn.cwd.clone(),
+                env: HashMap::new(),
+                expiration: ExecExpiration::Timeout(SANDBOXED_FS_TIMEOUT),
+                sandbox_permissions: SandboxPermissions::UseDefault,
+                additional_permissions,
+                justification: None,
+            },
+            None,
+        )
+        .map_err(|error| SandboxedFsError::ProcessFailed {
+            path: path.to_path_buf(),
+            exit_code: -1,
+            message: error.to_string(),
+        })?;
+    let output =
+        execute_env(exec_request, None)
+            .await
+            .map_err(|error| SandboxedFsError::ProcessFailed {
+                path: path.to_path_buf(),
+                exit_code: -1,
+                message: error.to_string(),
+            })?;
+
+    if output.timed_out {
+        return Err(SandboxedFsError::TimedOut {
+            path: path.to_path_buf(),
+        });
+    }
+    if output.exit_code != 0 {
+        let stderr = output.stderr.text.trim();
+        let stdout = output.stdout.text.trim();
+        let message = if !stderr.is_empty() {
+            stderr.to_string()
+        } else if !stdout.is_empty() {
+            stdout.to_string()
+        } else {
+            "no error details emitted".to_string()
+        };
+        return Err(SandboxedFsError::ProcessFailed {
+            path: path.to_path_buf(),
+            exit_code: output.exit_code,
+            message,
+        });
+    }
+
+    let response: FsResponse =
+        serde_json::from_str(output.stdout.text.trim()).map_err(|error| {
+            SandboxedFsError::InvalidResponse {
+                path: path.to_path_buf(),
+                message: format!("failed to parse helper response: {error}"),
+            }
+        })?;
+
+    match response {
+        FsResponse::Success { payload } => Ok(payload),
+        FsResponse::Error { error } => Err(SandboxedFsError::Operation {
+            path: path.to_path_buf(),
+            error,
+        }),
+    }
+}
+
+async fn effective_granted_permissions(session: &Session) -> Option<PermissionProfile> {
+    let granted_session_permissions = session.granted_session_permissions().await;
+    let granted_turn_permissions = session.granted_turn_permissions().await;
+    merge_permission_profiles(
+        granted_session_permissions.as_ref(),
+        granted_turn_permissions.as_ref(),
+    )
+}
+
+fn resolve_codex_exe(turn: &TurnContext) -> Result<PathBuf, SandboxedFsError> {
+    #[cfg(target_os = "windows")]
+    {
+        let current_exe =
+            std::env::current_exe().map_err(|error| SandboxedFsError::ResolveExe {
+                message: error.to_string(),
+            })?;
+        if is_codex_launcher(&current_exe) {
+            return Ok(current_exe);
+        }
+        if let Some(helper) = sibling_fs_helper_launcher(&current_exe)
+            && helper.is_file()
+        {
+            return Ok(helper);
+        }
+        Ok(codex_windows_sandbox::resolve_current_exe_for_launch(
+            &turn.config.codex_home,
+            "codex.exe",
+        ))
+    }
+    #[cfg(not(target_os = "windows"))]
+    {
+        let _ = turn;
+        let current_exe =
+            std::env::current_exe().map_err(|error| SandboxedFsError::ResolveExe {
+                message: error.to_string(),
+            })?;
+        if is_codex_launcher(&current_exe) {
+            return Ok(current_exe);
+        }
+        if let Some(helper) = sibling_fs_helper_launcher(&current_exe)
+            && helper.is_file()
+        {
+            return Ok(helper);
+        }
+        Ok(current_exe)
+    }
+}
+
+fn sibling_fs_helper_launcher(current_exe: &Path) -> Option<PathBuf> {
+    let bin_dir = current_exe.parent()?.parent()?;
+    #[cfg(target_os = "windows")]
+    let helper_name = "codex-write-config-schema.exe";
+    #[cfg(not(target_os = "windows"))]
+    let helper_name = "codex-write-config-schema";
+    Some(bin_dir.join(helper_name))
+}
+
+fn is_codex_launcher(path: &Path) -> bool {
+    path.file_name()
+        .and_then(std::ffi::OsStr::to_str)
+        .is_some_and(|name| {
+            matches!(
+                name,
+                "codex" | "codex.exe" | "codex-exec" | "codex-exec.exe"
+            )
+        })
+}

codex-rs/core/src/tools/handlers/view_image.rs

@@ -2,16 +2,16 @@ use async_trait::async_trait;
 use codex_protocol::models::ContentItem;
 use codex_protocol::models::FunctionCallOutputContentItem;
 use codex_protocol::models::ImageDetail;
-use codex_protocol::models::local_image_content_items_with_label_number;
+use codex_protocol::models::local_image_content_items_from_bytes_with_label_number;
 use codex_protocol::openai_models::InputModality;
 use codex_utils_image::PromptImageMode;
 use serde::Deserialize;
-use tokio::fs;
 
 use crate::function_tool::FunctionCallError;
 use crate::original_image_detail::can_request_original_image_detail;
 use crate::protocol::EventMsg;
 use crate::protocol::ViewImageToolCallEvent;
+use crate::sandboxed_fs;
 use crate::tools::context::FunctionToolOutput;
 use crate::tools::context::ToolInvocation;
 use crate::tools::context::ToolPayload;
@@ -88,20 +88,6 @@ impl ToolHandler for ViewImageHandler {
         };
 
         let abs_path = turn.resolve_path(Some(args.path));
-
-        let metadata = fs::metadata(&abs_path).await.map_err(|error| {
-            FunctionCallError::RespondToModel(format!(
-                "unable to locate image at `{}`: {error}",
-                abs_path.display()
-            ))
-        })?;
-
-        if !metadata.is_file() {
-            return Err(FunctionCallError::RespondToModel(format!(
-                "image path `{}` is not a file",
-                abs_path.display()
-            )));
-        }
         let event_path = abs_path.clone();
 
         let can_request_original_detail =
@@ -114,9 +100,17 @@ impl ToolHandler for ViewImageHandler {
             PromptImageMode::ResizeToFit
         };
         let image_detail = use_original_detail.then_some(ImageDetail::Original);
+        let image_bytes = sandboxed_fs::read_bytes(&session, &turn, &abs_path)
+            .await
+            .map_err(|error| {
+                FunctionCallError::RespondToModel(render_view_image_read_error(&abs_path, &error))
+            })?;
 
-        let content = local_image_content_items_with_label_number(
-            &abs_path, /*label_number*/ None, image_mode,
+        let content = local_image_content_items_from_bytes_with_label_number(
+            &abs_path,
+            image_bytes,
+            /*label_number*/ None,
+            image_mode,
         )
         .into_iter()
         .map(|item| match item {
@@ -142,3 +136,30 @@ impl ToolHandler for ViewImageHandler {
         Ok(FunctionToolOutput::from_content(content, Some(true)))
     }
 }
+
+fn render_view_image_read_error(
+    path: &std::path::Path,
+    error: &sandboxed_fs::SandboxedFsError,
+) -> String {
+    let operation_message = error
+        .operation_error_message()
+        .map(str::to_owned)
+        .unwrap_or_else(|| error.to_string());
+    match error.operation_error_kind() {
+        Some(codex_fs_ops::FsErrorKind::IsADirectory) => {
+            format!("image path `{}` is not a file", path.display())
+        }
+        Some(codex_fs_ops::FsErrorKind::NotFound) => {
+            format!(
+                "unable to locate image at `{}`: {operation_message}",
+                path.display()
+            )
+        }
+        Some(_) | None => {
+            format!(
+                "unable to read image at `{}`: {operation_message}",
+                path.display()
+            )
+        }
+    }
+}