fix: harden debug logging and LLM endpoint validation

SECURITY.md

@@ -27,7 +27,7 @@ Include:
 
 ## Security Notes
 
-- The app sends audio and text directly to OpenAI when you use the remote workflows.
+- Normal transcription is performed locally. Only transcribed text is optionally sent to OpenAI, OpenRouter, or a configured custom LLM endpoint for rewrite workflows.
 - Your OpenAI API key is read from the environment. Put it in `~/.config/blitztext-linux/secrets.env` (chmod `600`) or export the configured environment variable before launch.
 - Temporary audio files may exist briefly during processing.
 - Auto-paste uses `ydotool` to inject `Ctrl+V` into the focused application.

SUPPORT.md

@@ -5,7 +5,7 @@ BlitztextLinux is an experimental Linux desktop app. There is no service-level a
 ## Before Asking For Help
 
 - Make sure you can install the app with `bash scripts/install.sh`.
-- Confirm that your OpenAI API key is entered in the app settings if you use online workflows.
+- Set your API key in the environment variable configured in the app settings before using online workflows. Settings stores only that variable's name, not the API key itself.
 - Verify that `bash scripts/verify.sh` succeeds.
 - If you expect auto-paste, make sure `ydotool.service` is running and your session has access to the `input` group.
 - Read [docs/privacy.md](docs/privacy.md) before testing with sensitive content.

app/blitztext_linux.py

@@ -275,6 +275,17 @@ def init_ui(self) -> None:
         self.edit_base_url.setText(self.config.llm_base_url)
         self.edit_base_url.setPlaceholderText("https://openrouter.ai/api/v1")
         self.edit_base_url.setEnabled(self.config.llm_provider != "openai")
+        base_url_layout = QVBoxLayout()
+        base_url_layout.addWidget(self.edit_base_url)
+        if self.config.has_unsafe_llm_base_url:
+            self.lbl_unsafe_llm_base_url_notice = QLabel(
+                t("settings.base_url.unsafe_legacy_notice")
+            )
+            self.lbl_unsafe_llm_base_url_notice.setWordWrap(True)
+            self.lbl_unsafe_llm_base_url_notice.setStyleSheet("color: #b26a00; font-size: 10px;")
+            base_url_layout.addWidget(self.lbl_unsafe_llm_base_url_notice)
+        else:
+            self.lbl_unsafe_llm_base_url_notice = None
 
         self.edit_llm_model = QLineEdit()
         self.edit_llm_model.setText(self.config.llm_model)
@@ -347,7 +358,7 @@ def init_ui(self) -> None:
 
         form_llm.addRow(t("settings.llm_provider.label"), self.combo_llm_provider)
         form_llm.addRow(create_help_label(t("settings.llm_provider.help")))
-        form_llm.addRow(t("settings.base_url.label"), self.edit_base_url)
+        form_llm.addRow(t("settings.base_url.label"), base_url_layout)
         form_llm.addRow(create_help_label(t("settings.base_url.help")))
         form_llm.addRow(t("settings.llm_model.label"), self.edit_llm_model)
         form_llm.addRow(create_help_label(t("settings.llm_model.help")))

app/config.py

@@ -7,12 +7,15 @@
 from __future__ import annotations
 
 import copy
+import ipaddress
 import json
 import logging
 import os
 import re
+import unicodedata
 from pathlib import Path
 from typing import Any
+from urllib.parse import urlsplit
 
 from app.writing_presets import (
     DEFAULT_PRESET_KEY,
@@ -69,7 +72,12 @@
 VALID_TTS_PROVIDERS = {"piper", "openai"}
 VALID_OPENAI_TTS_VOICES = {"alloy", "ash", "ballad", "coral", "echo", "fable", "nova", "onyx", "sage", "shimmer", "verse", "marin", "cedar"}
 VALID_UI_LANGUAGES = set(I18N_LANGUAGES)
-BASE_URL_RE = re.compile(r"^https?://", re.IGNORECASE)
+PRIVATE_IPV4_NETWORKS = (
+    ipaddress.ip_network("10.0.0.0/8"),
+    ipaddress.ip_network("172.16.0.0/12"),
+    ipaddress.ip_network("192.168.0.0/16"),
+)
+NUMERIC_HOST_PART_RE = re.compile(r"(?:0x[0-9a-f]+|0[0-7]*|[0-9]+)", re.IGNORECASE)
 VALID_HOTKEY_KEYS = {
     "KEY_LEFTALT", "KEY_RIGHTALT", "KEY_RIGHTCTRL", "KEY_LEFTCTRL",
     "KEY_F13", "KEY_F14", "KEY_F15", "KEY_F16",
@@ -93,6 +101,7 @@ def __init__(self, config_dir: Path | None = None) -> None:
         self.config_file = self.config_dir / "config.json"
         self._legacy_openai_api_key_present = False
         self._legacy_openai_api_key_value = ""
+        self._has_unsafe_llm_base_url = False
 
         self._data = self._load()
         self._validate_and_sanitize()
@@ -144,6 +153,7 @@ def save(self) -> None:
             self._data = payload
             self._legacy_openai_api_key_present = False
             self._legacy_openai_api_key_value = ""
+            self._has_unsafe_llm_base_url = False
         except OSError as exc:
             raise ConfigError(f"Config konnte nicht gespeichert werden: {exc}") from exc
 
@@ -170,6 +180,10 @@ def resolve_openai_api_key(self) -> str:
     def has_legacy_openai_api_key(self) -> bool:
         return self._legacy_openai_api_key_present
 
+    @property
+    def has_unsafe_llm_base_url(self) -> bool:
+        return self._has_unsafe_llm_base_url
+
     @property
     def llm_provider(self) -> str:
         value = self._data.get("llm_provider", DEFAULTS["llm_provider"])
@@ -183,7 +197,7 @@ def llm_provider(self, value: str) -> None:
 
     @property
     def llm_base_url(self) -> str:
-        return _normalize_base_url(self._data.get("llm_base_url", ""))
+        return self._data.get("llm_base_url", "")
 
     @llm_base_url.setter
     def llm_base_url(self, value: str) -> None:
@@ -489,7 +503,12 @@ def _validate_and_sanitize(self) -> None:
 
         if self._data.get("llm_provider") not in VALID_LLM_PROVIDERS:
             self._data["llm_provider"] = DEFAULTS["llm_provider"]
-        self._data["llm_base_url"] = _normalize_base_url(self._data.get("llm_base_url", ""))
+        try:
+            self._data["llm_base_url"] = _normalize_base_url(self._data.get("llm_base_url", ""))
+        except ValueError:
+            self._data["llm_base_url"] = ""
+            self._has_unsafe_llm_base_url = True
+            logger.warning("Removed unsafe LLM base URL from configuration")
         self._data["llm_model"] = _normalize_model(self._data.get("llm_model", DEFAULTS["llm_model"]))
 
         if "workflows" not in self._data or not isinstance(self._data["workflows"], dict):
@@ -528,11 +547,62 @@ def _normalize_env_var_name(value: Any) -> str:
 
 def _normalize_base_url(value: Any) -> str:
     if not isinstance(value, str):
-        return ""
+        raise ValueError("LLM base URL must be a string")
     candidate = value.strip()
-    if not candidate or not BASE_URL_RE.match(candidate):
+    if not candidate:
         return ""
-    return candidate
+    if any(char.isspace() or unicodedata.category(char) in {"Cc", "Cf"} for char in candidate):
+        raise ValueError("LLM base URL must not contain whitespace or control characters")
+
+    try:
+        parsed = urlsplit(candidate)
+        hostname = parsed.hostname
+        port = parsed.port
+    except ValueError as exc:
+        raise ValueError("LLM base URL must contain a valid host and port") from exc
+
+    if parsed.scheme.lower() not in {"http", "https"}:
+        raise ValueError("LLM base URL must use http or https")
+    if not hostname or parsed.username is not None or parsed.password is not None:
+        raise ValueError("LLM base URL must not contain credentials and requires a host")
+    if "%" in hostname:
+        raise ValueError("LLM base URL must not use an encoded host")
+    if port is not None and not 0 <= port <= 65535:
+        raise ValueError("LLM base URL must contain a valid port")
+
+    if _looks_like_alternate_numeric_ipv4(hostname):
+        raise ValueError("LLM base URL must use a canonical IP address")
+    if parsed.scheme.lower() == "https":
+        return candidate
+
+    if hostname.lower() == "localhost":
+        return candidate
+
+    try:
+        address = ipaddress.ip_address(hostname)
+    except ValueError as exc:
+        raise ValueError("LLM base URL requires HTTPS for non-local endpoints") from exc
+
+    if str(address) != hostname:
+        raise ValueError("LLM base URL must use a canonical IP address")
+    if address.version == 6 and str(address) == "::1":
+        return candidate
+    if address.version == 4 and (
+        str(address) == "127.0.0.1" or any(address in network for network in PRIVATE_IPV4_NETWORKS)
+    ):
+        return candidate
+    raise ValueError("LLM base URL requires HTTPS for non-local endpoints")
+
+
+def _looks_like_alternate_numeric_ipv4(hostname: str) -> bool:
+    parts = hostname.split(".")
+    if not parts or not all(NUMERIC_HOST_PART_RE.fullmatch(part) for part in parts):
+        return False
+    try:
+        address = ipaddress.IPv4Address(hostname)
+    except ValueError:
+        return True
+    return str(address) != hostname
 
 
 def _normalize_model(value: Any) -> str:

app/hotkey_service.py

@@ -58,12 +58,6 @@ def hotkey_display_name(key_name: str) -> str:
 # Alle bekannten Meta- und Shift-Keycodes (als Namen; werden zur Laufzeit in Codes umgewandelt)
 _ALL_META_KEY_NAMES = ("KEY_LEFTMETA", "KEY_RIGHTMETA")
 _ALL_SHIFT_KEY_NAMES = ("KEY_LEFTSHIFT", "KEY_RIGHTSHIFT")
-_DEBUG_MODIFIER_KEY_NAMES = (
-    "KEY_LEFTALT", "KEY_RIGHTALT",
-    "KEY_LEFTCTRL", "KEY_RIGHTCTRL",
-    "KEY_LEFTMETA", "KEY_RIGHTMETA",
-    "KEY_LEFTSHIFT", "KEY_RIGHTSHIFT",
-)
 
 
 def _modifier_match(
@@ -96,11 +90,7 @@ def _modifier_match(
         result = False
         reason = "unexpected_shift"
 
-    logger.debug(
-        "modifier_match result=%s reason=%s pressed=%s required_meta=%s required_shift=%s all_meta=%s all_shift=%s",
-        result, reason, sorted(pressed), sorted(meta_codes), sorted(shift_codes),
-        sorted(all_meta_codes), sorted(all_shift_codes),
-    )
+    logger.debug("modifier_match result=%s reason=%s", result, reason)
     return result
 
 
@@ -216,10 +206,6 @@ def run(self) -> None:
         all_shift_codes = {
             getattr(ec, k) for k in _ALL_SHIFT_KEY_NAMES if hasattr(ec, k)
         }
-        debug_modifier_codes = {
-            getattr(ec, k): k for k in _DEBUG_MODIFIER_KEY_NAMES if hasattr(ec, k)
-        }
-
         hotkeys = []
         for workflow, tkey, mod_names in _HOTKEY_MAP:
             if workflow == WorkflowType.TRANSCRIPTION:
@@ -303,16 +289,6 @@ def run(self) -> None:
                         elif value == 0:
                             pressed.discard(code)
 
-                        key_name = _key_name(ec, code)
-                        active_modifiers = sorted(
-                            name for mod_code, name in debug_modifier_codes.items()
-                            if mod_code in pressed
-                        )
-                        logger.debug(
-                            "evdev key event device=%s key=%s code=%s value=%s active_modifiers=%s",
-                            getattr(dev, "path", "<unknown>"), key_name, code, value, active_modifiers,
-                        )
-
                         # --- Hold-Modus: KEY_UP des aktiven Trigger-Keys stoppt ---
                         if self._mode == "hold" and value == 0 and _hold_active is not None:
                             for wf, tcode, _, _ in hotkeys:
@@ -456,15 +432,6 @@ def _refresh_keyboard_devices(fd_to_dev: Dict[int, Any], transcription_key: str,
     return {dev.fd: dev for dev in devices}
 
 
-def _key_name(ecodes, code: int) -> str:
-    name = ecodes.KEY.get(code) if hasattr(ecodes, "KEY") else None
-    if isinstance(name, list):
-        return "/".join(str(part) for part in name)
-    if name:
-        return str(name)
-    return str(code)
-
-
 def _group_names() -> Set[str]:
     try:
         import grp

app/i18n.py

@@ -43,7 +43,8 @@
         "settings.llm_provider.custom_endpoint": "Eigener Endpunkt",
         "settings.llm_provider.help": "OpenAI = Standard. OpenRouter und 'Eigener Endpunkt' nutzen das OpenAI-kompatible API über eine eigene Basis-URL und ein eigenes Modell.",
         "settings.base_url.label": "Basis-URL (base_url):",
-        "settings.base_url.help": "Leer = OpenAI-Standard. Für OpenRouter: https://openrouter.ai/api/v1. Muss mit http:// oder https:// beginnen.",
+        "settings.base_url.help": "Leer = OpenAI-Standard. Öffentliche Endpunkte müssen https:// verwenden; http:// ist nur für localhost, 127.0.0.1, ::1 und private IPv4-Netze erlaubt.",
+        "settings.base_url.unsafe_legacy_notice": "Eine unsichere HTTP-Basis-URL aus der Konfiguration wurde entfernt. Verwende für öffentliche Endpunkte HTTPS.",
         "settings.llm_model.label": "LLM-Modell:",
         "settings.llm_model.help": "Modellname beim Anbieter, z. B. 'gpt-4o-mini' (OpenAI) oder 'openai/gpt-4o' (OpenRouter).",
         "settings.tone.label": "Ziel-Tonfall:",
@@ -241,7 +242,8 @@
         "settings.llm_provider.custom_endpoint": "Custom endpoint",
         "settings.llm_provider.help": "OpenAI = default. OpenRouter and 'Custom endpoint' use the OpenAI-compatible API with a custom base URL and custom model.",
         "settings.base_url.label": "Base URL (base_url):",
-        "settings.base_url.help": "Empty = OpenAI default. For OpenRouter: https://openrouter.ai/api/v1. Must start with http:// or https://.",
+        "settings.base_url.help": "Empty = OpenAI default. Public endpoints must use https://; http:// is only allowed for localhost, 127.0.0.1, ::1, and private IPv4 networks.",
+        "settings.base_url.unsafe_legacy_notice": "An unsafe HTTP base URL from the configuration was removed. Use HTTPS for public endpoints.",
         "settings.llm_model.label": "LLM model:",
         "settings.llm_model.help": "Model name at the provider, e.g. 'gpt-4o-mini' (OpenAI) or 'openai/gpt-4o' (OpenRouter).",
         "settings.tone.label": "Target tone:",

docs/privacy.md

@@ -2,18 +2,18 @@
 
 ## BlitztextLinux
 
-BlitztextLinux stores the OpenAI API key in:
+BlitztextLinux stores only the configured API-key environment-variable name in:
 
 ```text
 ~/.config/blitztext-linux/config.json
 ```
 
-That file is written with restrictive permissions (`0600`) so only the current user can read it.
+That file is written with restrictive permissions (`0600`) so only the current user can read it. The API key itself is read from the configured environment variable or from `~/.config/blitztext-linux/secrets.env`, which must use permissions `0600`.
 
 ## Data flow
 
 - Local transcription workflows stay on the machine.
-- LLM workflows send the transcribed text to OpenAI for rewriting.
+- LLM workflows optionally send the transcribed text to OpenAI, OpenRouter, or a configured custom endpoint for rewriting.
 - Temporary audio files are created during processing and are removed when the workflow finishes or is cancelled.
 - Workflow output may be placed on the clipboard so you can paste it into another app.
 

tests/test_config.py

@@ -200,6 +200,88 @@ def test_save_never_writes_api_key_with_provider_fields(self, config_dir):
         assert saved["llm_provider"] == "openrouter"
 
 
+class TestLLMBaseUrlSecurity:
+    @pytest.mark.parametrize(
+        ("value", "expected"),
+        [
+            ("https://api.example.com/v1", "https://api.example.com/v1"),
+            ("https://8.8.8.8/v1", "https://8.8.8.8/v1"),
+            ("https://[2001:4860:4860::8888]/v1", "https://[2001:4860:4860::8888]/v1"),
+            ("http://localhost:11434/v1", "http://localhost:11434/v1"),
+            ("http://127.0.0.1:11434/v1", "http://127.0.0.1:11434/v1"),
+            ("http://[::1]:11434/v1", "http://[::1]:11434/v1"),
+            ("http://10.0.0.1/v1", "http://10.0.0.1/v1"),
+            ("http://172.16.0.1/v1", "http://172.16.0.1/v1"),
+            ("http://192.168.1.1/v1", "http://192.168.1.1/v1"),
+        ],
+    )
+    def test_direct_setter_accepts_https_and_explicit_local_http_ranges(self, config, value, expected):
+        config.llm_base_url = value
+        assert config.llm_base_url == expected
+
+    @pytest.mark.parametrize(
+        "value",
+        [
+            "http://api.example.com/v1",
+            "http://8.8.8.8/v1",
+            "http://172.32.0.1/v1",
+            "http://127.0.0.2/v1",
+            "http://169.254.1.1/v1",
+            "http://[::ffff:127.0.0.1]/v1",
+            "http://2130706433/v1",
+            "http://0x7f000001/v1",
+            "http://0177.0.0.1/v1",
+            "http://%31%32%37.0.0.1/v1",
+            "http:///v1",
+            "http://local\nhost/v1",
+            "https://user:password@example.com/v1",
+            "https://example.com:99999/v1",
+            "https://0177.0.0.1/v1",
+            "https://127.000.000.001/v1",
+            "https://999.1.1.1/v1",
+            "https://api.example.com/\x7f",
+            "https://api.example.com/\u0080",
+        ],
+    )
+    def test_direct_setter_rejects_unsafe_or_malformed_urls(self, config, value):
+        with pytest.raises(ValueError, match="LLM base URL"):
+            config.llm_base_url = value
+
+    @pytest.mark.parametrize(
+        "unsafe_url",
+        [
+            "https://0177.0.0.1/v1",
+            "https://999.1.1.1/v1",
+        ],
+    )
+    def test_stored_noncanonical_numeric_https_url_is_cleared(self, config_dir, unsafe_url):
+        config_dir.mkdir(parents=True, exist_ok=True)
+        (config_dir / "config.json").write_text(
+            json.dumps({"llm_base_url": unsafe_url}), encoding="utf-8"
+        )
+
+        loaded = BlitztextConfig(config_dir=config_dir)
+
+        assert loaded.llm_base_url == ""
+        assert loaded.has_unsafe_llm_base_url is True
+
+    def test_legacy_public_http_url_is_cleared_and_warned_without_echoing_url(self, config_dir, caplog):
+        config_dir.mkdir(parents=True, exist_ok=True)
+        unsafe_url = "http://api.example.com/v1"
+        (config_dir / "config.json").write_text(
+            json.dumps({"llm_base_url": unsafe_url}), encoding="utf-8"
+        )
+
+        with caplog.at_level(logging.WARNING, logger="blitztext.config"):
+            loaded = BlitztextConfig(config_dir=config_dir)
+
+        assert loaded.llm_base_url == ""
+        assert loaded.has_unsafe_llm_base_url is True
+        records = [record for record in caplog.records if "unsafe LLM base URL" in record.message]
+        assert len(records) == 1
+        assert unsafe_url not in records[0].message
+
+
 class TestTranscriptionHotkey:
     def test_valid_hotkey_is_accepted(self, config):
         config.transcription_hotkey = "KEY_F13"