code push

fgex-lib/firegex/nfproxy/internals/__init__.py

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+from inspect import signature
+from firegex.nfproxy.internals.models import Action, FullStreamAction
+from firegex.nfproxy.internals.models import FilterHandler, PacketHandlerResult
+import functools
+from firegex.nfproxy.internals.data import DataStreamCtx
+from firegex.nfproxy.internals.exceptions import NotReadyToRun
+from firegex.nfproxy.internals.data import RawPacket
+
+def context_call(glob, func, *args, **kargs):
+    glob["__firegex_tmp_args"] = args
+    glob["__firegex_tmp_kargs"] = kargs
+    glob["__firege_tmp_call"] = func
+    res = eval("__firege_tmp_call(*__firegex_tmp_args, **__firegex_tmp_kargs)", glob, glob)
+    del glob["__firegex_tmp_args"]
+    del glob["__firegex_tmp_kargs"]
+    del glob["__firege_tmp_call"]
+    return res
+
+def generate_filter_structure(filters: list[str], proto:str, glob:dict) -> list[FilterHandler]:
+    from firegex.nfproxy.models import type_annotations_associations
+    if proto not in type_annotations_associations.keys():
+        raise Exception("Invalid protocol")
+    res = []
+    valid_annotation_type = type_annotations_associations[proto]
+    def add_func_to_list(func):
+        if not callable(func):
+            raise Exception(f"{func} is not a function")
+        sig = signature(func)
+        params_function = {}
+        
+        for k, v in sig.parameters.items():
+            if v.annotation in valid_annotation_type.keys():
+                params_function[v.annotation] = valid_annotation_type[v.annotation]
+            else:
+                raise Exception(f"Invalid type annotation {v.annotation} for function {func.__name__}")
+        
+        res.append(
+            FilterHandler(
+                func=func,
+                name=func.__name__,
+                params=params_function,
+                proto=proto
+            )
+        )
+    
+    for filter in filters:
+        if not isinstance(filter, str):
+            raise Exception("Invalid filter list: must be a list of strings")
+        if filter in glob.keys():
+            add_func_to_list(glob[filter])
+        else:
+            raise Exception(f"Filter {filter} not found")
+    return res
+
+def get_filters_info(code:str, proto:str) -> list[FilterHandler]:
+    glob = {}
+    exec(code, glob, glob)
+    exec("import firegex.nfproxy", glob, glob)
+    filters = eval("firegex.nfproxy.get_pyfilters()", glob, glob)
+    try:
+        return generate_filter_structure(filters, proto, glob)
+    finally:
+        exec("firegex.nfproxy.clear_pyfilter_registry()", glob, glob)
+        
+
+def get_filter_names(code:str, proto:str) -> list[str]:
+    return [ele.name for ele in get_filters_info(code, proto)]    
+
+def handle_packet(glob: dict) -> None:
+    internal_data = DataStreamCtx(glob)
+    print("I'm here", flush=True)
+    cache_call = {} # Cache of the data handler calls
+    
+    pkt_info = RawPacket._fetch_packet(internal_data)
+    internal_data.current_pkt = pkt_info
+    cache_call[RawPacket] = pkt_info
+    
+    final_result = Action.ACCEPT
+    data_size = len(pkt_info.data)
+    
+    result = PacketHandlerResult(glob)
+    
+    if internal_data.stream_size+data_size > internal_data.stream_max_size:
+        match internal_data.full_stream_action:
+            case FullStreamAction.FLUSH:
+                internal_data.stream = []
+                internal_data.stream_size = 0
+                for func in internal_data.flush_action_set:
+                    func()
+            case FullStreamAction.ACCEPT:
+                result.action = Action.ACCEPT
+                return result.set_result()
+            case FullStreamAction.REJECT:
+                result.action = Action.REJECT
+                result.matched_by = "@MAX_STREAM_SIZE_REACHED"
+                return result.set_result()
+            case FullStreamAction.REJECT:
+                result.action = Action.DROP
+                result.matched_by = "@MAX_STREAM_SIZE_REACHED"
+                return result.set_result()
+    
+    internal_data.stream.append(pkt_info)
+    internal_data.stream_size += data_size
+    
+    func_name = None
+    mangled_packet = None
+    for filter in internal_data.filter_call_info:
+        final_params = []
+        skip_call = False
+        for data_type, data_func in filter.params.items():
+            if data_type not in cache_call.keys():
+                try:
+                    cache_call[data_type] = data_func(internal_data)
+                except NotReadyToRun:
+                    cache_call[data_type] = None
+                    skip_call = True
+                    break
+            final_params.append(cache_call[data_type])
+        if skip_call:
+            continue
+        res = context_call(glob, filter.func, *final_params)
+        
+        if res is None:
+            continue #ACCEPTED
+        if not isinstance(res, Action):
+            raise Exception(f"Invalid return type {type(res)} for function {filter.name}")
+        if res == Action.MANGLE:
+            mangled_packet = pkt_info.raw_packet
+        if res != Action.ACCEPT:
+            func_name = filter.name
+            final_result = res
+            break
+    
+    result.action = final_result
+    result.matched_by = func_name
+    result.mangled_packet = mangled_packet
+    
+    return result.set_result()
+
+
+def compile(glob:dict) -> None:
+    internal_data = DataStreamCtx(glob)
+
+    glob["print"] = functools.partial(print, flush = True)
+    
+    filters = glob["__firegex_pyfilter_enabled"]
+    proto = glob["__firegex_proto"]
+    
+    internal_data.filter_call_info = generate_filter_structure(filters, proto, glob)
+
+    if "FGEX_STREAM_MAX_SIZE" in glob and int(glob["FGEX_STREAM_MAX_SIZE"]) > 0:
+        internal_data.stream_max_size = int(glob["FGEX_STREAM_MAX_SIZE"])
+    else:
+        internal_data.stream_max_size = 1*8e20 # 1MB default value
+    
+    if "FGEX_FULL_STREAM_ACTION" in glob and isinstance(glob["FGEX_FULL_STREAM_ACTION"], FullStreamAction):
+        internal_data.full_stream_action = glob["FGEX_FULL_STREAM_ACTION"]
+    else:
+        internal_data.full_stream_action = FullStreamAction.FLUSH
+    
+    PacketHandlerResult(glob).reset_result()
+