#1800 - Fixed routing and processing of ICMP packets in the Router class
This commit is contained in:
Chris McCarthy
@@ -744,14 +744,12 @@ class ICMP:
|
||||
:param frame: The Frame containing the ICMP packet to process.
|
||||
"""
|
||||
if frame.icmp.icmp_type == ICMPType.ECHO_REQUEST:
|
||||
self.sys_log.info(f"Received echo request from {frame.ip.src_ip}")
|
||||
if not is_reattempt:
|
||||
self.sys_log.info(f"Received echo request from {frame.ip.src_ip}")
|
||||
target_mac_address = self.arp.get_arp_cache_mac_address(frame.ip.src_ip)
|
||||
|
||||
src_nic = self.arp.get_arp_cache_nic(frame.ip.src_ip)
|
||||
if not src_nic:
|
||||
print(self.sys_log.hostname)
|
||||
print(frame.ip.src_ip)
|
||||
self.arp.show()
|
||||
self.arp.send_arp_request(frame.ip.src_ip)
|
||||
self.process_icmp(frame=frame, from_nic=from_nic, is_reattempt=True)
|
||||
return
|
||||
@@ -932,14 +930,13 @@ class Node(SimComponent):
|
||||
|
||||
def show(self):
|
||||
"""Prints a table of the NICs on the Node."""
|
||||
table = PrettyTable(["MAC Address", "Address", "Default Gateway", "Speed", "Status"])
|
||||
table = PrettyTable(["MAC Address", "Address", "Speed", "Status"])
|
||||
table.title = f"{self.hostname} Network Interface Cards"
|
||||
for nic in self.nics.values():
|
||||
table.add_row(
|
||||
[
|
||||
nic.mac_address,
|
||||
f"{nic.ip_address}/{nic.ip_network.prefixlen}",
|
||||
nic.gateway,
|
||||
nic.speed,
|
||||
"Enabled" if nic.enabled else "Disabled",
|
||||
]
|
||||
|
||||
@@ -69,14 +69,14 @@ class AccessControlList(SimComponent):
|
||||
return self._acl
|
||||
|
||||
def add_rule(
|
||||
self,
|
||||
action: ACLAction,
|
||||
protocol: Optional[IPProtocol] = None,
|
||||
src_ip: Optional[Union[str, IPv4Address]] = None,
|
||||
src_port: Optional[Port] = None,
|
||||
dst_ip: Optional[Union[str, IPv4Address]] = None,
|
||||
dst_port: Optional[Port] = None,
|
||||
position: int = 0,
|
||||
self,
|
||||
action: ACLAction,
|
||||
protocol: Optional[IPProtocol] = None,
|
||||
src_ip: Optional[Union[str, IPv4Address]] = None,
|
||||
src_port: Optional[Port] = None,
|
||||
dst_ip: Optional[Union[str, IPv4Address]] = None,
|
||||
dst_port: Optional[Port] = None,
|
||||
position: int = 0,
|
||||
) -> None:
|
||||
if isinstance(src_ip, str):
|
||||
src_ip = IPv4Address(src_ip)
|
||||
@@ -96,12 +96,12 @@ class AccessControlList(SimComponent):
|
||||
raise ValueError(f"Position {position} is out of bounds.")
|
||||
|
||||
def is_permitted(
|
||||
self,
|
||||
protocol: IPProtocol,
|
||||
src_ip: Union[str, IPv4Address],
|
||||
src_port: Optional[Port],
|
||||
dst_ip: Union[str, IPv4Address],
|
||||
dst_port: Optional[Port],
|
||||
self,
|
||||
protocol: IPProtocol,
|
||||
src_ip: Union[str, IPv4Address],
|
||||
src_port: Optional[Port],
|
||||
dst_ip: Union[str, IPv4Address],
|
||||
dst_port: Optional[Port],
|
||||
) -> Tuple[bool, Optional[Union[str, ACLRule]]]:
|
||||
if not isinstance(src_ip, IPv4Address):
|
||||
src_ip = IPv4Address(src_ip)
|
||||
@@ -112,23 +112,23 @@ class AccessControlList(SimComponent):
|
||||
continue
|
||||
|
||||
if (
|
||||
(rule.src_ip == src_ip or rule.src_ip is None)
|
||||
and (rule.dst_ip == dst_ip or rule.dst_ip is None)
|
||||
and (rule.protocol == protocol or rule.protocol is None)
|
||||
and (rule.src_port == src_port or rule.src_port is None)
|
||||
and (rule.dst_port == dst_port or rule.dst_port is None)
|
||||
(rule.src_ip == src_ip or rule.src_ip is None)
|
||||
and (rule.dst_ip == dst_ip or rule.dst_ip is None)
|
||||
and (rule.protocol == protocol or rule.protocol is None)
|
||||
and (rule.src_port == src_port or rule.src_port is None)
|
||||
and (rule.dst_port == dst_port or rule.dst_port is None)
|
||||
):
|
||||
return rule.action == ACLAction.PERMIT, rule
|
||||
|
||||
return self.implicit_action == ACLAction.PERMIT, f"Implicit {self.implicit_action.name}"
|
||||
|
||||
def get_relevant_rules(
|
||||
self,
|
||||
protocol: IPProtocol,
|
||||
src_ip: Union[str, IPv4Address],
|
||||
src_port: Port,
|
||||
dst_ip: Union[str, IPv4Address],
|
||||
dst_port: Port,
|
||||
self,
|
||||
protocol: IPProtocol,
|
||||
src_ip: Union[str, IPv4Address],
|
||||
src_port: Port,
|
||||
dst_ip: Union[str, IPv4Address],
|
||||
dst_port: Port,
|
||||
) -> List[ACLRule]:
|
||||
if not isinstance(src_ip, IPv4Address):
|
||||
src_ip = IPv4Address(src_ip)
|
||||
@@ -140,11 +140,11 @@ class AccessControlList(SimComponent):
|
||||
continue
|
||||
|
||||
if (
|
||||
(rule.src_ip == src_ip or rule.src_ip is None)
|
||||
or (rule.dst_ip == dst_ip or rule.dst_ip is None)
|
||||
or (rule.protocol == protocol or rule.protocol is None)
|
||||
or (rule.src_port == src_port or rule.src_port is None)
|
||||
or (rule.dst_port == dst_port or rule.dst_port is None)
|
||||
(rule.src_ip == src_ip or rule.src_ip is None)
|
||||
or (rule.dst_ip == dst_ip or rule.dst_ip is None)
|
||||
or (rule.protocol == protocol or rule.protocol is None)
|
||||
or (rule.src_port == src_port or rule.src_port is None)
|
||||
or (rule.dst_port == dst_port or rule.dst_port is None)
|
||||
):
|
||||
relevant_rules.append(rule)
|
||||
|
||||
@@ -247,11 +247,11 @@ class RouteTable(SimComponent):
|
||||
pass
|
||||
|
||||
def add_route(
|
||||
self,
|
||||
address: Union[IPv4Address, str],
|
||||
subnet_mask: Union[IPv4Address, str],
|
||||
next_hop: Union[IPv4Address, str],
|
||||
metric: float = 0.0,
|
||||
self,
|
||||
address: Union[IPv4Address, str],
|
||||
subnet_mask: Union[IPv4Address, str],
|
||||
next_hop: Union[IPv4Address, str],
|
||||
metric: float = 0.0,
|
||||
):
|
||||
"""Add a route to the routing table.
|
||||
|
||||
@@ -367,36 +367,46 @@ class RouterICMP(ICMP):
|
||||
# determine if request is for router interface or whether it needs to be routed
|
||||
|
||||
for nic in self.router.nics.values():
|
||||
if nic.ip_address == frame.ip.dst_ip and nic.enabled:
|
||||
# reply to the request
|
||||
self.sys_log.info(f"Received echo request from {frame.ip.src_ip}")
|
||||
target_mac_address = self.arp.get_arp_cache_mac_address(frame.ip.src_ip)
|
||||
src_nic = self.arp.get_arp_cache_nic(frame.ip.src_ip)
|
||||
tcp_header = TCPHeader(src_port=Port.ARP, dst_port=Port.ARP)
|
||||
if nic.ip_address == frame.ip.dst_ip:
|
||||
if nic.enabled:
|
||||
# reply to the request
|
||||
if not is_reattempt:
|
||||
self.sys_log.info(f"Received echo request from {frame.ip.src_ip}")
|
||||
target_mac_address = self.arp.get_arp_cache_mac_address(frame.ip.src_ip)
|
||||
src_nic = self.arp.get_arp_cache_nic(frame.ip.src_ip)
|
||||
tcp_header = TCPHeader(src_port=Port.ARP, dst_port=Port.ARP)
|
||||
|
||||
# Network Layer
|
||||
ip_packet = IPPacket(src_ip=nic.ip_address, dst_ip=frame.ip.src_ip, protocol=IPProtocol.ICMP)
|
||||
# Data Link Layer
|
||||
ethernet_header = EthernetHeader(src_mac_addr=src_nic.mac_address, dst_mac_addr=target_mac_address)
|
||||
icmp_reply_packet = ICMPPacket(
|
||||
icmp_type=ICMPType.ECHO_REPLY,
|
||||
icmp_code=0,
|
||||
identifier=frame.icmp.identifier,
|
||||
sequence=frame.icmp.sequence + 1,
|
||||
)
|
||||
frame = Frame(ethernet=ethernet_header, ip=ip_packet, tcp=tcp_header, icmp=icmp_reply_packet)
|
||||
self.sys_log.info(f"Sending echo reply to {frame.ip.dst_ip}")
|
||||
# Network Layer
|
||||
ip_packet = IPPacket(src_ip=nic.ip_address, dst_ip=frame.ip.src_ip, protocol=IPProtocol.ICMP)
|
||||
# Data Link Layer
|
||||
ethernet_header = EthernetHeader(src_mac_addr=src_nic.mac_address, dst_mac_addr=target_mac_address)
|
||||
icmp_reply_packet = ICMPPacket(
|
||||
icmp_type=ICMPType.ECHO_REPLY,
|
||||
icmp_code=0,
|
||||
identifier=frame.icmp.identifier,
|
||||
sequence=frame.icmp.sequence + 1,
|
||||
)
|
||||
frame = Frame(ethernet=ethernet_header, ip=ip_packet, tcp=tcp_header, icmp=icmp_reply_packet)
|
||||
self.sys_log.info(f"Sending echo reply to {frame.ip.dst_ip}")
|
||||
|
||||
src_nic.send_frame(frame)
|
||||
src_nic.send_frame(frame)
|
||||
return
|
||||
|
||||
# Route the frame
|
||||
self.router.route_frame(frame, from_nic)
|
||||
|
||||
elif frame.icmp.icmp_type == ICMPType.ECHO_REPLY:
|
||||
self.sys_log.info(f"Received echo reply from {frame.ip.src_ip}")
|
||||
if not self.request_replies.get(frame.icmp.identifier):
|
||||
self.request_replies[frame.icmp.identifier] = 0
|
||||
self.request_replies[frame.icmp.identifier] += 1
|
||||
for nic in self.router.nics.values():
|
||||
if nic.ip_address == frame.ip.dst_ip:
|
||||
if nic.enabled:
|
||||
self.sys_log.info(f"Received echo reply from {frame.ip.src_ip}")
|
||||
if not self.request_replies.get(frame.icmp.identifier):
|
||||
self.request_replies[frame.icmp.identifier] = 0
|
||||
self.request_replies[frame.icmp.identifier] += 1
|
||||
|
||||
return
|
||||
# Route the frame
|
||||
self.router.route_frame(frame, from_nic)
|
||||
|
||||
|
||||
class Router(Node):
|
||||
@@ -436,25 +446,34 @@ class Router(Node):
|
||||
pass
|
||||
|
||||
def route_frame(self, frame: Frame, from_nic: NIC, re_attempt: bool = False) -> None:
|
||||
if not re_attempt:
|
||||
# Check if src ip is on network of one of the NICs
|
||||
nic = self.arp.get_arp_cache_nic(frame.ip.dst_ip)
|
||||
target_mac = self.arp.get_arp_cache_mac_address(frame.ip.dst_ip)
|
||||
if not nic:
|
||||
self.arp.send_arp_request(frame.ip.dst_ip)
|
||||
return self.route_frame(frame=frame, from_nic=from_nic, re_attempt=True)
|
||||
for nic in self.nics.values():
|
||||
if nic.enabled and frame.ip.dst_ip in nic.ip_network:
|
||||
from_port = self._get_port_of_nic(from_nic)
|
||||
to_port = self._get_port_of_nic(nic)
|
||||
self.sys_log.info(f"Routing frame to internally from port {from_port} to port {to_port}")
|
||||
frame.decrement_ttl()
|
||||
frame.ethernet.src_mac_addr = nic.mac_address
|
||||
frame.ethernet.dst_mac_addr = target_mac
|
||||
nic.send_frame(frame)
|
||||
return
|
||||
else:
|
||||
# Check if src ip is on network of one of the NICs
|
||||
nic = self.arp.get_arp_cache_nic(frame.ip.dst_ip)
|
||||
target_mac = self.arp.get_arp_cache_mac_address(frame.ip.dst_ip)
|
||||
|
||||
if re_attempt and not nic:
|
||||
self.sys_log.info(f"Destination {frame.ip.dst_ip} is unreachable")
|
||||
return
|
||||
|
||||
if not nic:
|
||||
self.arp.send_arp_request(frame.ip.dst_ip)
|
||||
return self.route_frame(frame=frame, from_nic=from_nic, re_attempt=True)
|
||||
|
||||
if not nic.enabled:
|
||||
# TODO: Add sys_log here
|
||||
return
|
||||
|
||||
if frame.ip.dst_ip in nic.ip_network:
|
||||
from_port = self._get_port_of_nic(from_nic)
|
||||
to_port = self._get_port_of_nic(nic)
|
||||
self.sys_log.info(f"Routing frame to internally from port {from_port} to port {to_port}")
|
||||
frame.decrement_ttl()
|
||||
frame.ethernet.src_mac_addr = nic.mac_address
|
||||
frame.ethernet.dst_mac_addr = target_mac
|
||||
nic.send_frame(frame)
|
||||
return
|
||||
else:
|
||||
pass
|
||||
# TODO: Deal with routing from route tables
|
||||
|
||||
def receive_frame(self, frame: Frame, from_nic: NIC):
|
||||
"""
|
||||
|
||||
Reference in New Issue
Block a user