WIP QUIC: Improving initial packet dissection and building.

scapy/layers/quic/__init__.py

@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# This file is part of Scapy
+# See https://scapy.net/ for more information
+
+"""
+[QUIC] Tools for handling QUIC packets and sessions.
+
+TODO:
+- Rework organization of QUIC layers. (e.g., layers for QUIC packet, QUIC payload, QUIC frame, etc.)
+- Implement cryptographic features for QUIC, including initial encryption contexts based on QUIC Version.
+- Implement automaton for Handshake, sessions, etc.
+- And more...
+"""

scapy/layers/quic/all.py

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# This file is part of Scapy
+# See https://scapy.net/ for more information
+
+"""
+Aggregate top level objects from all QUIC modules.
+"""
+
+from scapy.layers.quic.packet import *

scapy/layers/quic.py → scapy/layers/quic/basefields.py

@@ -1,40 +1,27 @@
 # SPDX-License-Identifier: GPL-2.0-only
 # This file is part of Scapy
 # See https://scapy.net/ for more information
-# Copyright (C) Gabriel Potter <gabriel[]potter[]fr>
 
 """
-QUIC
-
-The draft of a very basic implementation of the structures from [RFC 9000].
-This isn't binded to UDP by default as currently too incomplete.
-
-TODO:
-- payloads.
-- encryption.
-- automaton.
-- etc.
+QUIC base fields, used for QUIC packet parsing/building.
 """
-
 import struct
 
 from scapy.packet import (
     Packet,
 )
+
 from scapy.fields import (
     _EnumField,
-    BitEnumField,
     BitField,
-    ByteEnumField,
     ByteField,
     EnumField,
     Field,
     FieldLenField,
-    FieldListField,
     IntField,
     MultipleTypeField,
+    PacketListField,
     ShortField,
-    StrLenField,
     ThreeBytesField,
 )
 
@@ -69,6 +56,14 @@
     0x1E: "HANDSHAKE_DONE",
 }
 
+# QUIC Versions
+# https://www.iana.org/assignments/quic/quic.xhtml#quic-versions
+_quic_versions = {
+    0x00000000: "QUIC Version Negotiaion", # RFC9000 sect 17.2.1
+    0x00000001: "QUIC v1", # RFC9000 sect 15
+    0x6b3342cf: "QUIC v2", # RFC9369 sect 3.1
+}
+
 
 # RFC9000 sect 16
 class QuicVarIntField(Field[int, int]):
@@ -144,53 +139,24 @@ def i2repr(
 # RFC9000 sect 17 abstraction
 
 
-class QUIC(Packet):
-    match_subclass = True
 
-    @classmethod
-    def dispatch_hook(cls, _pkt=None, *args, **kargs):
-        """
-        Returns the right class for the given data.
-        """
-        if _pkt:
-            hdr = _pkt[0]
-            if hdr & 0x80:
-                # Long Header packets
-                if hdr & 0x40 == 0:
-                    return QUIC_Version
-                else:
-                    typ = (hdr & 0x30) >> 4
-                    return {
-                        0: QUIC_Initial,
-                        1: QUIC_0RTT,
-                        2: QUIC_Handshake,
-                        3: QUIC_Retry,
-                    }[typ]
+class QuicPacketNumberBitFieldLenField(BitField):
+    def i2m(self, pkt, x):
+        if x is None and pkt is not None:
+            PacketNumber = pkt.PacketNumber or 0
+            if PacketNumber < 0 or PacketNumber > 0xFFFFFFFF:
+                raise struct.error("requires 0 <= number <= 0xFFFFFFFF")
+            if PacketNumber < 0x100:
+                return 0
+            elif PacketNumber < 0x10000:
+                return 1
+            elif PacketNumber < 0x1000000:
+                return 2
             else:
-                # Short Header packets
-                return QUIC_1RTT
-        return QUIC_Initial
-
-    def mysummary(self):
-        return self.name
-
-
-# RFC9000 sect 17.2.1
-
-
-class QUIC_Version(QUIC):
-    name = "QUIC - Version Negotiation"
-    fields_desc = [
-        BitEnumField("HeaderForm", 1, 1, _quic_long_hdr),
-        BitField("Unused", 0, 7),
-        IntField("Version", 0),
-        FieldLenField("DstConnIDLen", None, length_of="DstConnID", fmt="B"),
-        StrLenField("DstConnID", "", length_from=lambda pkt: pkt.DstConnIDLen),
-        FieldLenField("SrcConnIDLen", None, length_of="SrcConnID", fmt="B"),
-        StrLenField("SrcConnID", "", length_from=lambda pkt: pkt.SrcConnIDLen),
-        FieldListField("SupportedVersions", [], IntField("", 0)),
-    ]
-
+                return 3
+        elif x is None:
+            return 0
+        return x
 
 # RFC9000 sect 17.2.2
 
@@ -227,116 +193,3 @@ class QUIC_Version(QUIC):
     ],
     ByteField(name, default),
 )
-
-
-class QuicPacketNumberBitFieldLenField(BitField):
-    def i2m(self, pkt, x):
-        if x is None and pkt is not None:
-            PacketNumber = pkt.PacketNumber or 0
-            if PacketNumber < 0 or PacketNumber > 0xFFFFFFFF:
-                raise struct.error("requires 0 <= number <= 0xFFFFFFFF")
-            if PacketNumber < 0x100:
-                return 0
-            elif PacketNumber < 0x10000:
-                return 1
-            elif PacketNumber < 0x1000000:
-                return 2
-            else:
-                return 3
-        elif x is None:
-            return 0
-        return x
-
-
-class QUIC_Initial(QUIC):
-    name = "QUIC - Initial"
-    Version = 0x00000001
-    fields_desc = (
-        [
-            BitEnumField("HeaderForm", 1, 1, _quic_long_hdr),
-            BitField("FixedBit", 1, 1),
-            BitEnumField("LongPacketType", 0, 2, _quic_long_pkttyp),
-            BitField("Reserved", 0, 2),
-            QuicPacketNumberBitFieldLenField("PacketNumberLen", None, 2),
-        ]
-        + QUIC_Version.fields_desc[2:7]
-        + [
-            QuicVarLenField("TokenLen", None, length_of="Token"),
-            StrLenField("Token", "", length_from=lambda pkt: pkt.TokenLen),
-            QuicVarIntField("Length", 0),
-            QuicPacketNumberField("PacketNumber", 0),
-        ]
-    )
-
-
-# RFC9000 sect 17.2.3
-class QUIC_0RTT(QUIC):
-    name = "QUIC - 0-RTT"
-    LongPacketType = 1
-    fields_desc = QUIC_Initial.fields_desc[:10] + [
-        QuicVarIntField("Length", 0),
-        QuicPacketNumberField("PacketNumber", 0),
-    ]
-
-
-# RFC9000 sect 17.2.4
-class QUIC_Handshake(QUIC):
-    name = "QUIC - Handshake"
-    LongPacketType = 2
-    fields_desc = QUIC_0RTT.fields_desc
-
-
-# RFC9000 sect 17.2.5
-class QUIC_Retry(QUIC):
-    name = "QUIC - Retry"
-    LongPacketType = 3
-    Version = 0x00000001
-    fields_desc = (
-        QUIC_Initial.fields_desc[:3]
-        + [
-            BitField("Unused", 0, 4),
-        ]
-        + QUIC_Version.fields_desc[2:7]
-    )
-
-
-# RFC9000 sect 17.3
-class QUIC_1RTT(QUIC):
-    name = "QUIC - 1-RTT"
-    fields_desc = [
-        BitEnumField("HeaderForm", 0, 1, _quic_long_hdr),
-        BitField("FixedBit", 1, 1),
-        BitField("SpinBit", 0, 1),
-        BitField("Reserved", 0, 2),
-        BitField("KeyPhase", 0, 1),
-        QuicPacketNumberBitFieldLenField("PacketNumberLen", None, 2),
-        # FIXME - Destination Connection ID
-        QuicPacketNumberField("PacketNumber", 0),
-    ]
-
-
-# RFC9000 sect 19.1
-class QUIC_PADDING(Packet):
-    fields_desc = [
-        ByteEnumField("Type", 0x00, _quic_payloads),
-    ]
-
-
-# RFC9000 sect 19.2
-class QUIC_PING(Packet):
-    fields_desc = [
-        ByteEnumField("Type", 0x01, _quic_payloads),
-    ]
-
-
-# RFC9000 sect 19.3
-class QUIC_ACK(Packet):
-    fields_desc = [
-        ByteEnumField("Type", 0x02, _quic_payloads),
-    ]
-
-
-# Bindings
-# bind_bottom_up(UDP, QUIC, dport=443)
-# bind_bottom_up(UDP, QUIC, sport=443)
-# bind_layers(UDP, QUIC, dport=443, sport=443)