Security review fixes

python/obsidian_rag/embedder.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import time
+import urllib.parse
 from typing import TYPE_CHECKING
 
 import httpx
@@ -21,6 +22,10 @@ class OllamaUnavailableError(EmbeddingError):
     """Raised when Ollama is unreachable."""
 
 
+class SecurityError(Exception):
+    """Raised when security validation fails."""
+
+
 class OllamaEmbedder:
     """Client for Ollama /api/embed endpoint (mxbai-embed-large, 1024-dim)."""
 
@@ -29,7 +34,20 @@ class OllamaEmbedder:
         self.model = config.embedding.model
         self.dimensions = config.embedding.dimensions
         self.batch_size = config.embedding.batch_size
+        self.local_only = config.security.local_only
         self._client = httpx.Client(timeout=DEFAULT_TIMEOUT)
+        self._validate_network_isolation()
+
+    def _validate_network_isolation(self):
+        """Validate that embedding service is local when local_only is True."""
+        if not self.local_only:
+            return
+        
+        parsed = urllib.parse.urlparse(self.base_url)
+        if parsed.hostname not in ['localhost', '127.0.0.1', '::1']:
+            raise SecurityError(
+                f"Remote embedding service not allowed when local_only=True: {self.base_url}"
+            )
 
     def is_available(self) -> bool:
         """Check if Ollama is reachable and has the model."""