fix(security): decrypt callback_vars on use, add roundtrip tests

tests/test_litellm/proxy/common_utils/test_callback_utils.py

@@ -6,6 +6,7 @@ sys.path.insert(
 )  # Adds the parent directory to the system path
 
 from litellm.proxy.common_utils.callback_utils import (
+    encrypt_logging_callback_vars,
     get_remaining_tokens_and_requests_from_request_data,
     normalize_callback_names,
     redact_sensitive_logging_metadata,
@@ -80,7 +81,11 @@ def test_normalize_callback_names_none_returns_empty_list():
 
 
 def test_normalize_callback_names_lowercases_strings():
-    assert normalize_callback_names(["SQS", "S3", "CUSTOM_CALLBACK"]) == ["sqs", "s3", "custom_callback"]
+    assert normalize_callback_names(["SQS", "S3", "CUSTOM_CALLBACK"]) == [
+        "sqs",
+        "s3",
+        "custom_callback",
+    ]
 
 
 # ---------------------------------------------------------------------------
@@ -141,7 +146,9 @@ def test_redact_does_not_mutate_original():
     }
     original_value = metadata["logging"][0]["callback_vars"]["langfuse_secret_key"]
     redact_sensitive_logging_metadata(metadata)
-    assert metadata["logging"][0]["callback_vars"]["langfuse_secret_key"] == original_value
+    assert (
+        metadata["logging"][0]["callback_vars"]["langfuse_secret_key"] == original_value
+    )
 
 
 def test_redact_returns_none_for_none_input():
@@ -173,3 +180,77 @@ def test_redact_mixed_env_and_real_values():
     assert vars_["langfuse_public_key"] == "os.environ/LANGFUSE_PUBLIC_KEY"
     assert vars_["langfuse_secret_key"] == "***"
 
+
+# ---------------------------------------------------------------------------
+# encrypt_logging_callback_vars tests
+# ---------------------------------------------------------------------------
+
+
+def _make_metadata(callback_vars: dict) -> dict:
+    return {
+        "logging": [
+            {
+                "callback_name": "langfuse",
+                "callback_type": "success_and_failure",
+                "callback_vars": callback_vars,
+            }
+        ]
+    }
+
+
+def test_encrypt_returns_none_for_none():
+    assert encrypt_logging_callback_vars(None) is None
+
+
+def test_encrypt_returns_unchanged_when_no_logging_key():
+    metadata = {"other_key": "value"}
+    result = encrypt_logging_callback_vars(metadata)
+    assert result == {"other_key": "value"}
+
+
+def test_encrypt_leaves_env_var_pointers_unchanged(monkeypatch):
+    monkeypatch.setenv("LITELLM_SALT_KEY", "test-salt-key-1234567890123456")
+    metadata = _make_metadata({"langfuse_secret_key": "os.environ/LANGFUSE_SECRET_KEY"})
+    result = encrypt_logging_callback_vars(metadata)
+    assert (
+        result["logging"][0]["callback_vars"]["langfuse_secret_key"]
+        == "os.environ/LANGFUSE_SECRET_KEY"
+    )
+
+
+def test_encrypt_real_values_are_changed(monkeypatch):
+    monkeypatch.setenv("LITELLM_SALT_KEY", "test-salt-key-1234567890123456")
+    plaintext = "sk-lf-supersecret"
+    metadata = _make_metadata({"langfuse_secret_key": plaintext})
+    result = encrypt_logging_callback_vars(metadata)
+    encrypted = result["logging"][0]["callback_vars"]["langfuse_secret_key"]
+    assert encrypted != plaintext
+    assert isinstance(encrypted, str)
+
+
+def test_encrypt_then_decrypt_roundtrip(monkeypatch):
+    """Encrypt a value and confirm decrypt_value_helper returns the original."""
+    monkeypatch.setenv("LITELLM_SALT_KEY", "test-salt-key-1234567890123456")
+    from litellm.proxy.common_utils.encrypt_decrypt_utils import decrypt_value_helper
+
+    plaintext = "pk-lf-abc123"
+    metadata = _make_metadata({"langfuse_public_key": plaintext})
+    encrypt_logging_callback_vars(metadata)
+    encrypted = metadata["logging"][0]["callback_vars"]["langfuse_public_key"]
+    assert encrypted != plaintext
+
+    recovered = decrypt_value_helper(
+        value=encrypted, key="langfuse_public_key", return_original_value=True
+    )
+    assert recovered == plaintext
+
+
+def test_encrypt_mutates_in_place(monkeypatch):
+    """encrypt_logging_callback_vars modifies the dict in-place."""
+    monkeypatch.setenv("LITELLM_SALT_KEY", "test-salt-key-1234567890123456")
+    metadata = _make_metadata({"langfuse_secret_key": "sk-lf-real"})
+    returned = encrypt_logging_callback_vars(metadata)
+    assert returned is metadata
+    assert (
+        metadata["logging"][0]["callback_vars"]["langfuse_secret_key"] != "sk-lf-real"
+    )