from modules.firewall.models import Rule, Protocol, Mode, Action from utils import nftables_int_to_json, ip_family, NFTableManager, is_ip_parse import copy class FiregexTables(NFTableManager): rules_chain_in = "firewall_rules_in" rules_chain_out = "firewall_rules_out" rules_chain_fwd = "firewall_rules_fwd" def init_comands(self, policy:str=Action.ACCEPT, allow_loopback=False, allow_established=False, allow_icmp=False): return [ {"add":{"chain":{ "family":"inet", "table":self.table_name, "name":self.rules_chain_in, "type":"filter", "hook":"prerouting", "prio":0, "policy":policy }}}, {"add":{"chain":{ "family":"inet", "table":self.table_name, "name":self.rules_chain_fwd, "type":"filter", "hook":"forward", "prio":0, "policy":policy }}}, {"add":{"chain":{ "family":"inet", "table":self.table_name, "name":self.rules_chain_out, "type":"filter", "hook":"postrouting", "prio":0, "policy":Action.ACCEPT }}}, ] + ([ { "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 []) + ([ { "add":{ "rule": { "family": "inet", "table": self.table_name, "chain": self.rules_chain_in, "expr": [{ "match": { "op": "==", "left": { "meta": { "key": "l4proto" } }, "right": "icmp"} }, { "accept": None }] }}}, { "add":{ "rule": { "family": "inet", "table": self.table_name, "chain": self.rules_chain_fwd, "expr": [{ "match": { "op": "==", "left": { "meta": { "key": "l4proto" } }, "right": "icmp"} }, { "accept": None }] }}}, { "add":{ "rule": { "family": "inet", "table": self.table_name, "chain": self.rules_chain_in, "expr": [{ "match": { "op": "==", "left": { "meta": { "key": "l4proto" } }, "right": "ipv6-icmp"} }, { "accept": None }] }}}, { "add":{ "rule": { "family": "inet", "table": self.table_name, "chain": self.rules_chain_fwd, "expr": [{ "match": { "op": "==", "left": { "meta": { "key": "l4proto" } }, "right": "ipv6-icmp"} }, { "accept": None }] }}} ] if allow_icmp 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}}}, {"flush":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_fwd}}}, {"delete":{"chain":{"table":self.table_name,"family":"inet", "name":self.rules_chain_fwd}}}, ]) def set(self, srvs:list[Rule], policy:str="accept", allow_loopback=False, allow_established=False, allow_icmp=False): srvs = list(srvs) self.reset() if policy == Action.REJECT: policy = Action.DROP srvs.append(Rule( proto=Protocol.ANY, src="", dst="", port_src_from=1, port_dst_from=1, port_src_to=65535, port_dst_to=65535, action=Action.REJECT, mode=Mode.IN )) rules = self.init_comands(policy, allow_loopback=allow_loopback, allow_established=allow_established, allow_icmp=allow_icmp) + self.get_rules(*srvs) self.cmd(*rules) def get_rules(self,*srvs:Rule): rules = [] final_srvs:list[Rule] = [] for ele in srvs: if ele.proto == Protocol.BOTH: udp_rule = copy.deepcopy(ele) udp_rule.proto = Protocol.UDP.value ele.proto = Protocol.TCP.value final_srvs.append(udp_rule) final_srvs.append(ele) for srv in final_srvs: ip_filters = [] if srv.src != "": if is_ip_parse(srv.src): ip_filters.append({'match': {'left': {'payload': {'protocol': ip_family(srv.src), 'field': 'saddr'}}, 'op': '==', 'right': nftables_int_to_json(srv.src)}}) else: ip_filters.append({"match": { "op": "==", "left": { "meta": { "key": "iifname" } }, "right": srv.src} }) if srv.dst != "": if is_ip_parse(srv.dst): ip_filters.append({'match': {'left': {'payload': {'protocol': ip_family(srv.dst), 'field': 'daddr'}}, 'op': '==', 'right': nftables_int_to_json(srv.dst)}}) else: ip_filters.append({"match": { "op": "==", "left": { "meta": { "key": "oifname" } }, "right": srv.dst} }) port_filters = [] if not srv.proto in [Protocol.ANY, Protocol.BOTH]: 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': {'meta': {'key': 'l4proto'}}, 'op': '==', 'right': srv.proto}}) #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 if srv.input_mode else self.rules_chain_fwd, "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))