openclaw/src/infra/tmp-openclaw-dir.ts

import fs from "node:fs";
import os from "node:os";
import path from "node:path";

export const POSIX_OPENCLAW_TMP_DIR = "/tmp/openclaw";

type ResolvePreferredOpenClawTmpDirOptions = {
  accessSync?: (path: string, mode?: number) => void;
  lstatSync?: (path: string) => {
    isDirectory(): boolean;
    isSymbolicLink(): boolean;
    mode?: number;
    uid?: number;
  };
  mkdirSync?: (path: string, opts: { recursive: boolean; mode?: number }) => void;
  getuid?: () => number | undefined;
  tmpdir?: () => string;
};

type MaybeNodeError = { code?: string };

function isNodeErrorWithCode(err: unknown, code: string): err is MaybeNodeError {
  return (
    typeof err === "object" &&
    err !== null &&
    "code" in err &&
    (err as MaybeNodeError).code === code
  );
}

export function resolvePreferredOpenClawTmpDir(
  options: ResolvePreferredOpenClawTmpDirOptions = {},
): string {
  const accessSync = options.accessSync ?? fs.accessSync;
  const lstatSync = options.lstatSync ?? fs.lstatSync;
  const mkdirSync = options.mkdirSync ?? fs.mkdirSync;
  const getuid =
    options.getuid ??
    (() => {
      try {
        return typeof process.getuid === "function" ? process.getuid() : undefined;
      } catch {
        return undefined;
      }
    });
  const tmpdir = options.tmpdir ?? os.tmpdir;
  const uid = getuid();

  const isSecureDirForUser = (st: { mode?: number; uid?: number }): boolean => {
    if (uid === undefined) {
      return true;
    }
    if (typeof st.uid === "number" && st.uid !== uid) {
      return false;
    }
    // Avoid group/other writable dirs when running on multi-user hosts.
    if (typeof st.mode === "number" && (st.mode & 0o022) !== 0) {
      return false;
    }
    return true;
  };

  const fallback = (): string => {
    const base = tmpdir();
    const suffix = uid === undefined ? "openclaw" : `openclaw-${uid}`;
    return path.join(base, suffix);
  };

  const isTrustedPreferredDir = (st: {
    isDirectory(): boolean;
    isSymbolicLink(): boolean;
    mode?: number;
    uid?: number;
  }): boolean => {
    return st.isDirectory() && !st.isSymbolicLink() && isSecureDirForUser(st);
  };

  const resolvePreferredState = (
    requireWritableAccess: boolean,
  ): "available" | "missing" | "invalid" => {
    try {
      const preferred = lstatSync(POSIX_OPENCLAW_TMP_DIR);
      if (!isTrustedPreferredDir(preferred)) {
        return "invalid";
      }
      if (requireWritableAccess) {
        accessSync(POSIX_OPENCLAW_TMP_DIR, fs.constants.W_OK | fs.constants.X_OK);
      }
      return "available";
    } catch (err) {
      if (isNodeErrorWithCode(err, "ENOENT")) {
        return "missing";
      }
      return "invalid";
    }
  };

  const existingPreferredState = resolvePreferredState(true);
  if (existingPreferredState === "available") {
    return POSIX_OPENCLAW_TMP_DIR;
  }
  if (existingPreferredState === "invalid") {
    return fallback();
  }

  try {
    accessSync("/tmp", fs.constants.W_OK | fs.constants.X_OK);
    // Create with a safe default; subsequent callers expect it exists.
    mkdirSync(POSIX_OPENCLAW_TMP_DIR, { recursive: true, mode: 0o700 });
    if (resolvePreferredState(true) !== "available") {
      return fallback();
    }
    return POSIX_OPENCLAW_TMP_DIR;
  } catch {
    return fallback();
  }
}