🛡️ Sentinel: Fix configuration injection and enhance security linting

- Add input validation to `scripts/rename.py` to prevent injection in configuration files.
- Sanitize double quotes in description for TOML compatibility.
- Use literal replacement in `re.sub` to prevent regex backreference injection.
- Enable `flake8-bandit` (S) rules in `ruff` for automated security checks.
- Add security journal entry in `.jules/sentinel.md`.

Author: google-labs-jules[bot]

pyproject.toml

@@ -36,7 +36,7 @@ build-backend = "hatchling.build"
 line-length = 120
 
 [tool.ruff.lint]
-select = ["E", "I"]
+select = ["E", "I", "S"]
 
 [tool.coverage.run]
 branch = true

scripts/rename.py

@@ -13,12 +13,27 @@
 @option("--email", required=True, help="Author email")
 @option("--github", required=True, help="GitHub username")
 def main(name: str, description: str, author: str, email: str, github: str):
-    # Validate name to prevent directory traversal or other injection
+    # Validate inputs to prevent configuration injection
+    for label, value in [
+        ("name", name),
+        ("description", description),
+        ("author", author),
+        ("email", email),
+        ("github", github),
+    ]:
+        if "\n" in value or "\r" in value:
+            raise UsageError(f"Invalid {label}: newlines are not allowed.")
+        if label != "description" and '"' in value:
+            raise UsageError(f"Invalid {label}: double quotes are not allowed.")
+
     if not re.match(r"^[a-zA-Z0-9_-]+$", name):
         raise UsageError(
             f"Invalid project name '{name}'. Only alphanumeric characters, dashes, and underscores are allowed."
         )
 
+    # Sanitize description for TOML double-quoted strings
+    description = description.replace('"', '\\"')
+
     source = name.replace("-", "_").lower()
 
     echo(f"Initializing project '{name}' (source: '{source}')...")
@@ -51,7 +66,8 @@ def main(name: str, description: str, author: str, email: str, github: str):
             continue
 
         content = path.read_text()
-        new_content = re.sub(pattern, replacement, content, flags=re.MULTILINE)
+        # Use a lambda for replacement to avoid regex backreference injection
+        new_content = re.sub(pattern, lambda _: replacement, content, flags=re.MULTILINE)
         path.write_text(new_content)
         echo(f"Updated {filepath}")