RAHHH

backend/lib/python3.12/site-packages/twisted/pair/ip.py

@@ -0,0 +1,78 @@
+# -*- test-case-name: twisted.pair.test.test_ip -*-
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE for details.
+
+#
+
+
+"""Support for working directly with IP packets"""
+
+import socket
+import struct
+
+from zope.interface import implementer
+
+from twisted.internet import protocol
+from twisted.pair import raw
+
+
+class IPHeader:
+    def __init__(self, data):
+        (
+            ihlversion,
+            self.tos,
+            self.tot_len,
+            self.fragment_id,
+            frag_off,
+            self.ttl,
+            self.protocol,
+            self.check,
+            saddr,
+            daddr,
+        ) = struct.unpack("!BBHHHBBH4s4s", data[:20])
+        self.saddr = socket.inet_ntoa(saddr)
+        self.daddr = socket.inet_ntoa(daddr)
+        self.version = ihlversion & 0x0F
+        self.ihl = ((ihlversion & 0xF0) >> 4) << 2
+        self.fragment_offset = frag_off & 0x1FFF
+        self.dont_fragment = frag_off & 0x4000 != 0
+        self.more_fragments = frag_off & 0x2000 != 0
+
+
+MAX_SIZE = 2**32
+
+
+@implementer(raw.IRawPacketProtocol)
+class IPProtocol(protocol.AbstractDatagramProtocol):
+    def __init__(self):
+        self.ipProtos = {}
+
+    def addProto(self, num, proto):
+        proto = raw.IRawDatagramProtocol(proto)
+        if num < 0:
+            raise TypeError("Added protocol must be positive or zero")
+        if num >= MAX_SIZE:
+            raise TypeError("Added protocol must fit in 32 bits")
+        if num not in self.ipProtos:
+            self.ipProtos[num] = []
+        self.ipProtos[num].append(proto)
+
+    def datagramReceived(self, data, partial, dest, source, protocol):
+        header = IPHeader(data)
+        for proto in self.ipProtos.get(header.protocol, ()):
+            proto.datagramReceived(
+                data=data[20:],
+                partial=partial,
+                source=header.saddr,
+                dest=header.daddr,
+                protocol=header.protocol,
+                version=header.version,
+                ihl=header.ihl,
+                tos=header.tos,
+                tot_len=header.tot_len,
+                fragment_id=header.fragment_id,
+                fragment_offset=header.fragment_offset,
+                dont_fragment=header.dont_fragment,
+                more_fragments=header.more_fragments,
+                ttl=header.ttl,
+            )