Private /tmp, no display, git over SSH and netlock check fixes

- /tmp: the agent gets its own (<state>/tmp, files older than 7 days are
  removed on start) — the host's /tmp holds sockets that lead out of the
  sandbox (tmux, X11, browsers' singleton sockets, other tools).
  OCSB_TMP=shared keeps the old behaviour. /tmp is mounted before the
  project and state binds so they stay visible if they live under /tmp
- DISPLAY, WAYLAND_DISPLAY, XAUTHORITY are empty in the sandbox and
  ~/.Xauthority is hidden; browsers must run headless
- GIT_SSH_COMMAND uses -F ~/.ssh/config: in the user namespace root-owned
  system ssh configs look owned by nobody and ssh refuses them
- netlock self-test checks that the proxy opens the tunnel, not that a
  remote site answers; failed self-tests now say so instead of exiting
  silently
- doctor: no false error for opencode outside a project
- skill and READMEs: worktrees only for code changes, private /tmp,
  headless browsers, troubleshooting entries

README.md

@@ -124,6 +124,7 @@ files are read, so you can use it in values. Relative paths are relative to the
 | `OCSB_PLUGINS` | skill-compact-resurrect | plugin files from `plugins/` (or absolute paths) |
 | `OCSB_PANEL` | `1` | "Tokens" panel in the web UI |
 | `OCSB_NOTIFICATIONS` | `1` | desktop notifications through a filtered D-Bus proxy |
+| `OCSB_TMP` | `private` | `private`: the agent's own `/tmp` in the state directory; `shared`: the host's `/tmp` |
 | `OCSB_SANDBOX` | `1` | `0` = filter and netlock only, no bubblewrap |
 | `OCSB_WORKTREES_DIR` | `../<project>-worktrees` | where worktrees go |
 | `OCSB_WT_PREFIX` | — | worktree directory = `<prefix><slug>` |
@@ -226,7 +227,11 @@ browser → :4196 (context panel inside OpenCode) → :4197
 Inside the sandbox:
 
 - **Writable:** the project, the worktrees directory, the state directory, `OCSB_RW`,
-  `OCSB_RW_HOME`, `/tmp`. Everything else is read-only.
+  `OCSB_RW_HOME` and a private `/tmp`. Everything else is read-only.
+- **Private `/tmp`:** the host's `/tmp` holds sockets that lead out of a sandbox (tmux, X11,
+  browsers' singleton sockets, other tools), so the agent gets its own, stored in
+  `<state>/tmp` (files older than 7 days are removed on start). Look there for its screenshots
+  and logs. Docker mounts of `/tmp` paths would point at the host's `/tmp` — mount project paths.
 - **Hidden:** `OCSB_HIDE_HOME`, `OCSB_HIDE`, private keys in `~/.ssh` (`config`, `known_hosts`
   and `*.pub` stay visible; the host's ssh-agent signs).
 - **Network:** `HTTP(S)_PROXY` point to the filter. `GIT_SSH_COMMAND` sends ssh through it with
@@ -238,8 +243,9 @@ Inside the sandbox:
 - **Session bus:** replaced by `xdg-dbus-proxy` that talks only to
   `org.freedesktop.Notifications`; the real bus would let the agent start processes outside
   the sandbox with `systemd-run --user`.
-- **Browser:** `xdg-open` is disabled for the agent; the UI is opened by `run` from your
-  normal session.
+- **No display:** `DISPLAY`, `WAYLAND_DISPLAY` and `XAUTHORITY` are empty and the X cookie is
+  hidden, so GUI programs cannot reach your desktop; run browsers (Playwright MCP, Chrome)
+  headless. `xdg-open` is disabled; the UI is opened by `run` from your normal session.
 - **No silent fallback:** with `OCSB_SANDBOX=1` and no working bubblewrap, `run` refuses to
   start.
 
@@ -260,7 +266,7 @@ place, requests to production — not to hold a determined attacker.
 - **Allowed hosts are a channel.** Data can leave through any host the rules allow.
 - **The project is writable.** Mistakes inside it are real; cc-safety-net blocks the common
   destructive commands, git keeps history — commit often.
-- `/tmp` is shared with the host.
+- With `OCSB_TMP=shared` the host's `/tmp` and its sockets are reachable.
 
 ## Troubleshooting
 
@@ -275,6 +281,8 @@ place, requests to production — not to hold a determined attacker.
 | `bubblewrap cannot create a sandbox` | unprivileged user namespaces are disabled (`kernel.unprivileged_userns_clone`, AppArmor userns restrictions) |
 | no "Tokens" panel | open port 4196, not 4197; see `<state>/data/opencode/log/context-panel.log` |
 | no notifications | install `xdg-dbus-proxy` |
+| browser tools fail (`Missing X server`, `Failed to connect to Wayland display`) | no display in the sandbox: run the browser headless (Playwright MCP: `--headless`) |
+| can't find a file the agent put in `/tmp` | it is in `~/.local/share/opencode-sandbox/<name>/tmp` |
 | `docker build` fails pulling images | the proxy reaches registries through squid: check `egress logs` |
 
 ## Uninstall

README.ru.md

@@ -123,6 +123,7 @@ squid.conf.
 | `OCSB_PLUGINS` | skill-compact-resurrect | файлы плагинов из `plugins/` (или абсолютные пути) |
 | `OCSB_PANEL` | `1` | панель «Токены» в веб-интерфейсе |
 | `OCSB_NOTIFICATIONS` | `1` | уведомления через фильтрующий прокси D-Bus |
+| `OCSB_TMP` | `private` | `private` — свой `/tmp` агента в каталоге состояния; `shared` — `/tmp` хоста |
 | `OCSB_SANDBOX` | `1` | `0` — только фильтр и netlock, без bubblewrap |
 | `OCSB_WORKTREES_DIR` | `../<проект>-worktrees` | куда класть worktree |
 | `OCSB_WT_PREFIX` | — | каталог дерева = `<префикс><slug>` |
@@ -225,8 +226,12 @@ opencode-sandbox run
 
 Внутри песочницы:
 
-- **На запись:** проект, каталог worktree, каталог состояния, `OCSB_RW`, `OCSB_RW_HOME`,
-  `/tmp`. Всё остальное — только чтение.
+- **На запись:** проект, каталог worktree, каталог состояния, `OCSB_RW`, `OCSB_RW_HOME` и
+  собственный `/tmp`. Всё остальное — только чтение.
+- **Свой `/tmp`:** в `/tmp` хоста лежат сокеты, через которые можно выйти из песочницы
+  (tmux, X11, сокеты браузеров, других программ), поэтому у агента свой `/tmp` — в
+  `<состояние>/tmp` (файлы старше 7 дней удаляются при запуске). Скриншоты и логи агента ищите
+  там. Docker смонтирует путь из `/tmp` из `/tmp` хоста — монтируйте пути проекта.
 - **Скрыто:** `OCSB_HIDE_HOME`, `OCSB_HIDE`, приватные ключи в `~/.ssh` (`config`,
   `known_hosts` и `*.pub` видны; подписывает ssh-agent хоста).
 - **Сеть:** `HTTP(S)_PROXY` указывают на фильтр. `GIT_SSH_COMMAND` пускает ssh через него
@@ -239,7 +244,9 @@ opencode-sandbox run
 - **Сессионная шина:** заменена на `xdg-dbus-proxy`, который пропускает только
   `org.freedesktop.Notifications`; настоящая шина позволила бы агенту запускать процессы вне
   песочницы через `systemd-run --user`.
-- **Браузер:** `xdg-open` агенту отключён; интерфейс открывает `run` из вашей обычной сессии.
+- **Нет экрана:** `DISPLAY`, `WAYLAND_DISPLAY` и `XAUTHORITY` пустые, cookie X скрыт — графические
+  программы до вашего рабочего стола не доберутся; браузеры (Playwright MCP, Chrome) — только
+  headless. `xdg-open` отключён; интерфейс открывает `run` из вашей обычной сессии.
 - **Без тихого отката:** при `OCSB_SANDBOX=1` и неработающем bubblewrap `run` не запустится.
 
 **Netlock** (`netlock setup`, sudo) создаёт группу `opencode-sandbox`, добавляет в неё вас и
@@ -260,7 +267,7 @@ opencode-sandbox run
   правила.
 - **Проект доступен на запись.** Ошибки внутри него настоящие; cc-safety-net блокирует
   типичные разрушительные команды, git хранит историю — коммитьте чаще.
-- `/tmp` общий с хостом.
+- С `OCSB_TMP=shared` доступны `/tmp` хоста и его сокеты.
 
 ## Решение проблем
 
@@ -275,6 +282,8 @@ opencode-sandbox run
 | `bubblewrap cannot create a sandbox` | отключены непривилегированные user namespaces (`kernel.unprivileged_userns_clone`, ограничения AppArmor) |
 | нет панели «Токены» | открывайте порт 4196, а не 4197; журнал — `<состояние>/data/opencode/log/context-panel.log` |
 | нет уведомлений | установите `xdg-dbus-proxy` |
+| браузерные инструменты падают (`Missing X server`, `Failed to connect to Wayland display`) | в песочнице нет экрана: запускайте браузер headless (Playwright MCP: `--headless`) |
+| не найти файл, который агент положил в `/tmp` | он в `~/.local/share/opencode-sandbox/<имя>/tmp` |
 | `docker build` не скачивает образы | реестры доступны через squid: смотрите `egress logs` |
 
 ## Удаление

lib/common.sh

@@ -19,7 +19,7 @@ ocsb_info() { echo "→ $*"; }
 
 OCSB_SCALARS=(
   OCSB_NAME OCSB_WEB_PORT OCSB_EGRESS_PORT OCSB_NETLOCK_GROUP OCSB_SANDBOX OCSB_PANEL
-  OCSB_NOTIFICATIONS OCSB_OPENCODE_BIN OCSB_ENV_FILE OCSB_KUBECONFIG OCSB_PASSWORD_FILE
+  OCSB_NOTIFICATIONS OCSB_TMP OCSB_OPENCODE_BIN OCSB_ENV_FILE OCSB_KUBECONFIG OCSB_PASSWORD_FILE
   OCSB_WORKTREES_DIR OCSB_WT_PREFIX OCSB_WT_BASE OCSB_WT_SLUG_REGEX OCSB_DOCKER_GW
   OCSB_STATE_DIR OCSB_OPENCODE_CONFIG OCSB_EGRESS_BASE
 )
@@ -33,6 +33,7 @@ ocsb_defaults() {
   OCSB_SANDBOX=1               # bubblewrap; 0 = egress filter and netlock only
   OCSB_PANEL=1                 # "Tokens" panel in the web UI (plugins/context-panel)
   OCSB_NOTIFICATIONS=1         # desktop notifications through a filtered D-Bus proxy
+  OCSB_TMP=private             # private: own /tmp in the state dir; shared: the host's /tmp
   OCSB_OPENCODE_BIN=""         # default: `opencode` from PATH
   OCSB_ENV_FILE=""             # KEY=VALUE file with tokens, exported to OpenCode
   OCSB_KUBECONFIG=""           # kubeconfig for the agent (~/.kube/config stays hidden)
@@ -53,7 +54,7 @@ ocsb_defaults() {
   OCSB_HIDE_HOME=(.gnupg .aws .azure .config/gcloud .kube/config .docker/config.json .netrc
     .git-credentials .config/gh/hosts.yml .password-store .local/share/keyrings .mozilla
     .config/google-chrome .config/chromium .config/BraveSoftware .claude .codex
-    .config/opencode .local/share/opencode)
+    .config/opencode .local/share/opencode .Xauthority)
   OCSB_SKILLS=(opencode-sandbox)  # skills mounted for the agent (names of skill directories)
   OCSB_SKILL_DIRS=()           # extra directories to look for skills in
   OCSB_PLUGINS=(skill-compact-resurrect/skill-compact-resurrect.v2.ts)  # files in plugins/

lib/run.sh

@@ -124,11 +124,23 @@ ocsb_bwrap_args() {
   OCSB_BWRAP=(
     --die-with-parent --new-session --unshare-pid --unshare-ipc --unshare-uts
     --ro-bind / / --dev /dev --proc /proc
-    --bind /tmp /tmp
+    --tmpfs "/run/user/${uid}"
+  )
+  # /tmp: the host's holds sockets that lead out of the sandbox (tmux, X11, browsers,
+  # other agents) — by default the agent gets its own, kept in the state directory.
+  # Mounted before the project and the state, so they stay visible if they live under /tmp
+  if [[ ${OCSB_TMP} == shared ]]; then
+    OCSB_BWRAP+=(--bind /tmp /tmp)
+  else
+    mkdir -p "${OCSB_STATE_DIR}/tmp"
+    chmod 700 "${OCSB_STATE_DIR}/tmp"
+    find "${OCSB_STATE_DIR}/tmp" -mindepth 1 -mtime +7 -delete 2>/dev/null || true
+    OCSB_BWRAP+=(--bind "${OCSB_STATE_DIR}/tmp" /tmp)
+  fi
+  OCSB_BWRAP+=(
     --bind "${OCSB_PROJECT_DIR}" "${OCSB_PROJECT_DIR}"
     --bind "${OCSB_WORKTREES_DIR}" "${OCSB_WORKTREES_DIR}"
     --bind "${OCSB_STATE_DIR}" "${OCSB_STATE_DIR}"
-    --tmpfs "/run/user/${uid}"
   )
   for p in "${OCSB_RW[@]}"; do
     p=$(ocsb_abs "${p}")
@@ -243,6 +255,8 @@ ocsb_run() {
     # No permission prompts in the sandbox: permission rules from all configs form one
     # list, the last match wins, and OPENCODE_CONFIG_CONTENT is the last document.
     # Denies are repeated after "*" so they still win.
+    # No display: GUI programs fail fast; browsers must run headless
+    env+=("DISPLAY=" "WAYLAND_DISPLAY=" "XAUTHORITY=")
     env+=('OPENCODE_CONFIG_CONTENT={"permission":{"bash":{"*":"allow","systemd-run *":"deny","sudo *":"deny"},"external_directory":{"*":"allow"}}}')
     echo "  sandbox: writable ${OCSB_PROJECT_DIR}, ${OCSB_WORKTREES_DIR}${OCSB_RW[*]:+, ${OCSB_RW[*]}}; the rest of the system is read-only"
   fi

skills/opencode-sandbox/SKILL.md

@@ -14,7 +14,7 @@ sandbox is on.
 |---|---|
 | The project, its worktrees directory, paths from `OCSB_RW` in `.opencode-sandbox/sandbox.conf` | read-write, real disk |
 | Toolchain caches in `~` (`.cache`, `.npm`, `.asdf`, `.bundle`, `.gem`, …) | read-write |
-| `/tmp` | read-write, shared with the host |
+| `/tmp` | read-write, **private** to the sandbox (on the host it is `<state>/tmp`; files older than 7 days are cleaned) |
 | Everything else | read-only |
 | Private SSH keys, `~/.gnupg`, cloud CLI credentials, `~/.kube/config`, browser profiles, other agents' configs, `OCSB_HIDE` paths | hidden (empty) |
 
@@ -39,6 +39,7 @@ sandbox is on.
 ## Things you cannot do
 
 - Open a browser (`xdg-open` is disabled): print the link for the user.
+- Run GUI programs: there is no display. Browsers (Playwright, Chrome) must run headless.
 - `sudo`, `systemd-run`: denied.
 - Start processes outside the sandbox through the session bus: only desktop notifications
   are reachable.
@@ -46,7 +47,8 @@ sandbox is on.
 ## Docker
 
 The Docker socket is available, so Docker can see the whole host. Mount only paths inside
-the project or its worktrees; never mount `/`, `~` or system directories.
+the project or its worktrees; never mount `/`, `~` or system directories. Do not mount `/tmp`
+paths: the Docker daemon sees the host's `/tmp`, not your private one.
 
 ## Worktrees