Files
firegex-traffic-viewer/backend/modules/firewall/nftables.py
2023-09-26 17:24:04 +02:00

126 lines
6.4 KiB
Python

from modules.firewall.models import Rule
from utils import nftables_int_to_json, ip_parse, ip_family, NFTableManager
class FiregexHijackRule():
def __init__(self, proto:str, ip_src:str, ip_dst:str, port_src_from:int, port_dst_from:int, port_src_to:int, port_dst_to:int, action:str, target:str, id:int):
self.id = id
self.target = target
self.proto = proto
self.ip_src = ip_src
self.ip_dst = ip_dst
self.port_src_from = min(port_src_from, port_src_to)
self.port_dst_from = min(port_dst_from, port_dst_to)
self.port_src_to = max(port_src_from, port_src_to)
self.port_dst_to = max(port_dst_from, port_dst_to)
self.action = action
def __eq__(self, o: object) -> bool:
if isinstance(o, FiregexHijackRule) or isinstance(o, Rule):
return self.action == o.action and self.proto == o.proto and\
ip_parse(self.ip_src) == ip_parse(o.ip_src) and ip_parse(self.ip_dst) == ip_parse(o.ip_dst) and\
int(self.port_src_from) == int(o.port_src_from) and int(self.port_dst_from) == int(o.port_dst_from) and\
int(self.port_src_to) == int(o.port_src_to) and int(self.port_dst_to) == int(o.port_dst_to)
return False
class FiregexTables(NFTableManager):
rules_chain_in = "firewall_rules_in"
rules_chain_out = "firewall_rules_out"
def init_comands(self, policy:str="accept", policy_out:str="accept", allow_loopback=False, allow_established=False):
return [
{"add":{"chain":{
"family":"inet",
"table":self.table_name,
"name":self.rules_chain_in,
"type":"filter",
"hook":"prerouting",
"prio":-150,
"policy":policy
}}},
{"add":{"chain":{
"family":"inet",
"table":self.table_name,
"name":self.rules_chain_out,
"type":"filter",
"hook":"postrouting",
"prio":-150,
"policy":policy_out
}}},
] + ([
{ "add":{ "rule": {
"family": "inet", "table": self.table_name, "chain": self.rules_chain_out,
"expr": [{ "match": { "op": "==", "left": { "meta": { "key": "iif"}}, "right": "lo"}},{"accept": None}]
}}},
{ "add":{ "rule": {
"family": "inet", "table": self.table_name, "chain": self.rules_chain_in,
"expr": [{ "match": { "op": "==", "left": { "meta": { "key": "iif"}}, "right": "lo"}},{"accept": None}]
}}}
] if allow_loopback else []) + ([
{ "add":{ "rule": {
"family": "inet", "table": self.table_name, "chain": self.rules_chain_in,
"expr": [{ "match": {"op": "in", "left": { "ct": { "key": "state" }},"right": ["established"]} }, { "accept": None }]
}}}
] if allow_established else [])
def __init__(self):
super().__init__(self.init_comands(),[
{"flush":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_in}}},
{"delete":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_in}}},
{"flush":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_out}}},
{"delete":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_out}}},
])
def set(self, srvs:list[Rule], policy:str="accept", allow_loopback=False, allow_established=False):
srvs = list(srvs)
self.reset()
if policy == "reject":
policy = "drop"
srvs.append(Rule(
proto="any",
ip_src="any",
ip_dst="any",
port_src_from=1,
port_dst_from=1,
port_src_to=65535,
port_dst_to=65535,
action="reject",
mode="I"
))
rules = self.init_comands(policy, allow_loopback=allow_loopback, allow_established=allow_established) + self.get_rules(*srvs)
self.cmd(*rules)
def get_rules(self,*srvs:Rule):
rules = []
for srv in srvs:
ip_filters = []
if srv.ip_src.lower() != "any" and srv.ip_dst.lower() != "any":
ip_filters = [
{'match': {'left': {'payload': {'protocol': ip_family(srv.ip_src), 'field': 'saddr'}}, 'op': '==', 'right': nftables_int_to_json(srv.ip_src)}},
{'match': {'left': {'payload': {'protocol': ip_family(srv.ip_dst), 'field': 'daddr'}}, 'op': '==', 'right': nftables_int_to_json(srv.ip_dst)}},
]
port_filters = []
if srv.proto != "any":
if srv.port_src_from != 1 or srv.port_src_to != 65535: #Any Port
port_filters.append({'match': {'left': {'payload': {'protocol': str(srv.proto), 'field': 'sport'}}, 'op': '>=', 'right': int(srv.port_src_from)}})
port_filters.append({'match': {'left': {'payload': {'protocol': str(srv.proto), 'field': 'sport'}}, 'op': '<=', 'right': int(srv.port_src_to)}})
if srv.port_dst_from != 1 or srv.port_dst_to != 65535: #Any Port
port_filters.append({'match': {'left': {'payload': {'protocol': str(srv.proto), 'field': 'dport'}}, 'op': '>=', 'right': int(srv.port_dst_from)}})
port_filters.append({'match': {'left': {'payload': {'protocol': str(srv.proto), 'field': 'dport'}}, 'op': '<=', 'right': int(srv.port_dst_to)}})
if len(port_filters) == 0:
port_filters.append({'match': {'left': {'payload': {'protocol': str(srv.proto), 'field': 'sport'}}, 'op': '!=', 'right': 0}}) #filter the protocol if no port is specified
end_rules = [{'accept': None} if srv.action == "accept" else {'reject': {}} if (srv.action == "reject" and not srv.output_mode) else {'drop': None}]
rules.append({ "add":{ "rule": {
"family": "inet",
"table": self.table_name,
"chain": self.rules_chain_out if srv.output_mode else self.rules_chain_in,
"expr": ip_filters + port_filters + end_rules
#If srv.output_mode is True, then the rule is in the output chain, so the reject action is not allowed
}}})
return rules
def add(self, *srvs:Rule):
self.cmd(*self.get_rules(*srvs))