litellm - 💡(How to fix) Fix Follow-up: OWASP ASI06 memory guard — prototype callback hook implementation

from litellm import completion
from litellm.integrations.custom_logger import CustomLogger
import re

class MemoryGuardCallback(CustomLogger):
    """OWASP ASI06 memory poisoning defense as a LiteLLM callback."""
    
    INJECTION_PATTERNS = [
        r"ignore (previous|prior|all) instructions",
        r"disregard (your|all) (previous |prior )?(instructions|rules|guidelines)",
        r"you are now (a |an )?(different|new|another)",
        r"system prompt",
        r"jailbreak",
        r"DAN mode",
    ]
    
    def async_pre_call_hook(self, user_api_key_dict, cache, data, call_type):
        messages = data.get("messages", [])
        for msg in messages:
            content = msg.get("content", "")
            if isinstance(content, str):
                for pattern in self.INJECTION_PATTERNS:
                    if re.search(pattern, content, re.IGNORECASE):
                        raise ValueError(f"ASI06: Memory poisoning pattern detected: '{pattern}'")
        return data

# Register the callback
import litellm
litellm.callbacks = [MemoryGuardCallback()]