Hermes-agent

agent/ssl_guard.py

@@ -0,0 +1,94 @@
+"""Preventive SSL CA certificate checks for Hermes Agent.
+
+This module catches broken CA bundle paths before OpenAI/httpx turns them into
+opaque ``FileNotFoundError: [Errno 2] No such file or directory`` failures.
+"""
+
+from __future__ import annotations
+
+import logging
+import os
+import ssl
+from pathlib import Path
+
+from agent.errors import SSLConfigurationError
+
+logger = logging.getLogger(__name__)
+
+_CA_BUNDLE_ENV_VARS = (
+    "HERMES_CA_BUNDLE",
+    "SSL_CERT_FILE",
+    "REQUESTS_CA_BUNDLE",
+    "CURL_CA_BUNDLE",
+)
+
+_SKIP_VALUES = {"1", "true", "yes", "on"}
+
+
+def _skip_ssl_guard_enabled() -> bool:
+    return os.getenv("HERMES_SKIP_SSL_GUARD", "").strip().lower() in _SKIP_VALUES
+
+
+def _repair_hint() -> str:
+    return (
+        "Repair: python -m pip install --force-reinstall certifi openai httpx\n"
+        "If you configured a custom corporate CA bundle, fix or unset the "
+        "broken CA bundle environment variable."
+    )
+
+
+def _ssl_err(message: str) -> SSLConfigurationError:
+    """Create a consistent, user-actionable SSL configuration error."""
+    return SSLConfigurationError(f"{message}\n{_repair_hint()}")
+
+
+def _validate_bundle_path(label: str, value: str, *, require_substantial: bool = False) -> None:
+    path = Path(value).expanduser()
+    if not path.exists():
+        raise _ssl_err(f"{label} points to a missing CA bundle: {value}")
+    if not path.is_file():
+        raise _ssl_err(f"{label} does not point to a CA bundle file: {value}")
+    if require_substantial and path.stat().st_size < 1024:
+        raise _ssl_err(f"{label} at {value} appears corrupted (too small)")
+    try:
+        ctx = ssl.create_default_context(cafile=str(path))
+    except Exception as exc:
+        raise _ssl_err(f"{label} CA bundle at {value} cannot be loaded: {exc}") from exc
+    if not ctx.get_ca_certs():
+        raise _ssl_err(f"{label} CA bundle at {value} did not load any certificates")
+
+
+def verify_ca_bundle() -> None:
+    """Verify configured and bundled CA certificates are present and loadable.
+
+    Raises:
+        SSLConfigurationError: If an explicit CA-bundle environment variable
+            points at a bad path, or if certifi's bundled ``cacert.pem`` is
+            missing/corrupt.
+    """
+    if _skip_ssl_guard_enabled():
+        logger.debug("SSL CA bundle guard skipped via HERMES_SKIP_SSL_GUARD")
+        return
+
+    for env_var in _CA_BUNDLE_ENV_VARS:
+        value = os.getenv(env_var)
+        if value:
+            _validate_bundle_path(env_var, value)
+
+    try:
+        import certifi
+    except Exception as exc:
+        raise _ssl_err(f"certifi is not importable: {exc}") from exc
+
+    ca_bundle = str(certifi.where())
+    _validate_bundle_path("certifi", ca_bundle, require_substantial=True)
+
+
+def verify_ca_bundle_with_fallback() -> None:
+    """Backward-compatible wrapper for older call sites.
+
+    The old PR name mentioned a platform fallback, but allowing startup with a
+    broken certifi bundle still leaves httpx/OpenAI and requests call sites
+    failing later. Keep the wrapper name but enforce the same check.
+    """
+    verify_ca_bundle()