stopped using mktemp

Dockerfile

@@ -1,5 +1,6 @@
 FROM python:3.8-alpine as builder
 
+RUN apk update
 RUN apk add --no-cache \
     linux-headers \
     tcpdump \

kube_hunter/modules/discovery/hosts.py

@@ -1,13 +1,14 @@
-import json
 import os
-import sys
+import struct
 import socket
 import logging
 import itertools
 import requests
 
+from pathlib import Path
 from enum import Enum
 from netaddr import IPNetwork, IPAddress, AddrFormatError
+from psutil import net_if_addrs
 
 from kube_hunter.conf import get_config
 from kube_hunter.modules.discovery.kubernetes_client import list_all_k8s_cluster_nodes
@@ -141,7 +142,7 @@ class FromPodHostDiscovery(Discovery):
 
             gateway_subnet = self.gateway_discovery()
             if gateway_subnet:
-                subnets.append(gateway_subnet)
+                subnets += gateway_subnet
 
             should_scan_apiserver = False
             if self.event.kubeservicehost:
@@ -225,22 +226,20 @@ class FromPodHostDiscovery(Discovery):
         # netifaces currently does not have a maintainer. so we backported to linux support only for this cause.
         # TODO: implement WMI queries for windows support
         # https://stackoverflow.com/a/6556951
-        if sys.platform in ["linux", "linux2"]:
-            try:
-                from pyroute2 import IPDB
+        if not Path("/proc/net/route").exists():
+            logging.debug("Error getting default gateway from /proc/net/route. not runnning in linux environment")
+            return False
 
-                ip = IPDB()
-                gateway_ip = ip.routes["default"]["gateway"]
-                ip.release()
-                return [gateway_ip, "24"]
-            except Exception as x:
-                logging.debug(f"Exception while fetching default gateway from container - {x}")
-            finally:
-                ip.release()
-        else:
-            logging.debug("Not running in a linux env, will not scan default subnet")
-
-        return False
+        try:
+            with open("/proc/net/route") as fh:
+                for line in fh:
+                    fields = line.strip().split()
+                    if fields[1] != "00000000" or not int(fields[3], 16) & 2:
+                        # If not default route or not RTF_GATEWAY, skip it
+                        continue
+                return [socket.inet_ntoa(struct.pack("<L", int(fields[2], 16))), "24"]
+        except Exception as x:
+            logging.debug(f"Exception when parsing /proc/net/route to figure default gateway: {x}")
 
     # querying AWS's interface metadata api v1 | works only from a pod
     def aws_metadata_v1_discovery(self):
@@ -361,61 +360,21 @@ class HostDiscovery(Discovery):
 
     # generate all subnets from all internal network interfaces
     def generate_interfaces_subnet(self, sn="24"):
-        if sys.platform == "win32":
-            return self.generate_interfaces_subnet_windows()
-        elif sys.platform in ["linux", "linux2"]:
-            return self.generate_interfaces_subnet_linux()
-
-    def generate_interfaces_subnet_linux(self, sn="24"):
-        try:
-            from pyroute2 import IPRoute
-
-            ip = IPRoute()
-            for i in ip.get_addr():
-                # whitelist only ipv4 ips
-                if i["family"] == socket.AF_INET:
-                    ipaddress = i[0].get_attr("IFA_ADDRESS")
-                    # TODO: add this instead of hardcoded 24 subnet, (add a flag for full scan option)
-                    # subnet = i['prefixlen']
-
+        ifaces = net_if_addrs()
+        for _, ifaceAddresses in ifaces.items():
+            # filter only ipv4 addresses on interface
+            ipv4_addresses = list(filter(lambda x: x.family == socket.AF_INET, ifaceAddresses))
+            if ipv4_addresses:
+                for address in ipv4_addresses:
                     # unless specified explicitly with localhost scan flag, skip localhost ip addresses
-                    if not self.event.localhost and ipaddress.startswith(InterfaceTypes.LOCALHOST.value):
+                    if not self.event.localhost and address.address.__str__().startswith(
+                        InterfaceTypes.LOCALHOST.value
+                    ):
                         continue
 
-                    ip_network = IPNetwork(f"{ipaddress}/{sn}")
+                    ip_network = IPNetwork(f"{address.address}/{sn}")
                     for ip in ip_network:
                         yield ip
-        except Exception as x:
-            logging.debug(f"Exception while generating subnet scan from local interfaces: {x}")
-        finally:
-            ip.release()
-
-    def generate_interfaces_subnet_windows(self, sn="24"):
-        from subprocess import check_output
-
-        local_subnets = (
-            check_output(
-                "powershell -NoLogo -NoProfile -NonInteractive -ExecutionPolicy bypass -Command "
-                ' "& {'
-                "Get-NetIPConfiguration | Get-NetIPAddress | Where-Object {$_.AddressFamily -eq 'IPv4'}"
-                " | Select-Object -Property IPAddress, PrefixLength | ConvertTo-Json "
-                ' "}',
-                shell=True,
-            )
-            .decode()
-            .strip()
-        )
-        try:
-            subnets = json.loads(local_subnets)
-            for subnet in subnets:
-                if not self.event.localhost and subnet["IPAddress"].startswith(InterfaceTypes.LOCALHOST.value):
-                    continue
-                ip_network = IPNetwork(f"{subnet['IPAddress']}/{sn}")
-                for ip in ip_network:
-                    yield ip
-
-        except Exception as x:
-            logging.debug(f"ERROR: Could not extract interface information using powershell - {x}")
 
 
 # for comparing prefixes

setup.cfg

@@ -31,7 +31,7 @@ zip_safe = False
 packages = find:
 install_requires =
     netaddr
-    pyroute2
+    psutil
     requests
     PrettyTable
     urllib3>=1.24.3