SMB: Implement encryption, cleanup RequireSignature

Author: gpotter2

.config/codespell_ignore.txt

@@ -7,6 +7,7 @@ browseable
 byteorder
 cace
 cas
+ciph
 componet
 comversion
 cros

doc/scapy/layers/smb.rst

@@ -5,8 +5,6 @@ Scapy provides pretty good support for SMB 2/3 and very partial support of SMB1.
 
 You can use the :class:`~scapy.layers.smb2.SMB2_Header` to dissect or build SMB2/3, or :class:`~scapy.layers.smb.SMB_Header` for SMB1.
 
-.. warning:: Encryption is currently not supported in neither the client nor server.
-
 .. _client:
 
 SMB 2/3 client
@@ -94,6 +92,12 @@ You might be wondering if you can pass the ``HashNT`` of the password of the use
 
 If you pay very close attention, you'll notice that in this case we aren't using the :class:`~scapy.layers.spnego.SPNEGOSSP` wrapper. You could have used ``ssp=SPNEGOSSP([t.ssp(1)])``.
 
+**smbclient forcing encryption**:
+
+.. code:: python
+
+   >>> smbclient("server1.domain.local", "admin", REQUIRE_ENCRYPTION=True)
+
 .. note::
 
     It is also possible to start the :class:`~scapy.layers.smbclient.smbclient` directly from the OS, using the following::

scapy/layers/ntlm.py

@@ -1680,9 +1680,7 @@ def GSS_Accept_sec_context(self, Context: CONTEXT, val=None):
                         EncryptedRandomSessionKey = b"\x00" * 16
                     else:
                         EncryptedRandomSessionKey = auth_tok.EncryptedRandomSessionKey
-                    ExportedSessionKey = RC4K(
-                        KeyExchangeKey, EncryptedRandomSessionKey
-                    )
+                    ExportedSessionKey = RC4K(KeyExchangeKey, EncryptedRandomSessionKey)
                 else:
                     ExportedSessionKey = KeyExchangeKey
                 Context.ExportedSessionKey = ExportedSessionKey
@@ -1800,6 +1798,7 @@ def _getSessionBaseKey(self, Context, auth_tok):
             return NTLMv2_ComputeSessionBaseKey(
                 ResponseKeyNT, auth_tok.NtChallengeResponse.NTProofStr
             )
+        log_runtime.debug("NTLMSSP: Bad credentials for %s" % username)
         return None
 
     def _checkLogin(self, Context, auth_tok):

scapy/layers/smb.py

@@ -67,7 +67,9 @@
 )
 from scapy.layers.smb2 import (
     STATUS_ERREF,
+    SMB2_Compression_Transform_Header,
     SMB2_Header,
+    SMB2_Transform_Header,
 )
 
 
@@ -919,11 +921,9 @@ def dispatch_hook(cls, _pkt=None, *args, **kargs):
             elif _pkt[0] == 0x13:  # LOGON_SAM_USER_RESPONSE
                 try:
                     i = _pkt.index(b"\xff\xff\xff\xff")
-                    NtVersion = (
-                        NETLOGON_SAM_LOGON_RESPONSE_NT40.fields_desc[-3].getfield(
-                            None, _pkt[i - 4:i]
-                        )[1]
-                    )
+                    NtVersion = NETLOGON_SAM_LOGON_RESPONSE_NT40.fields_desc[
+                        -3
+                    ].getfield(None, _pkt[i - 4 : i])[1]
                     if NtVersion.V1 and not NtVersion.V5:
                         return NETLOGON_SAM_LOGON_RESPONSE_NT40
                 except Exception:
@@ -1013,6 +1013,7 @@ class NETLOGON_SAM_LOGON_RESPONSE_NT40(NETLOGON):
 
 # [MS-ADTS] sect 6.3.1.8
 
+
 class NETLOGON_SAM_LOGON_RESPONSE(NETLOGON, DNSCompressedPacket):
     fields_desc = [
         LEShortEnumField("OpCode", 0x17, _NETLOGON_opcodes),
@@ -1085,8 +1086,7 @@ def pre_dissect(self, s):
         try:
             i = s.index(b"\xff\xff\xff\xff")
             self.fields["NtVersion"] = self.fields_desc[-3].getfield(
-                self,
-                s[i - 4:i]
+                self, s[i - 4 : i]
             )[1]
         except Exception:
             self.NtVersion = 0xB
@@ -1098,20 +1098,25 @@ def get_full(self):
 
 # [MS-BRWS] sect 2.2
 
+
 class BRWS(Packet):
     fields_desc = [
-        ByteEnumField("OpCode", 0x00, {
-            0x01: "HostAnnouncement",
-            0x02: "AnnouncementRequest",
-            0x08: "RequestElection",
-            0x09: "GetBackupListRequest",
-            0x0A: "GetBackupListResponse",
-            0x0B: "BecomeBackup",
-            0x0C: "DomainAnnouncement",
-            0x0D: "MasterAnnouncement",
-            0x0E: "ResetStateRequest",
-            0x0F: "LocalMasterAnnouncement",
-        }),
+        ByteEnumField(
+            "OpCode",
+            0x00,
+            {
+                0x01: "HostAnnouncement",
+                0x02: "AnnouncementRequest",
+                0x08: "RequestElection",
+                0x09: "GetBackupListRequest",
+                0x0A: "GetBackupListResponse",
+                0x0B: "BecomeBackup",
+                0x0C: "DomainAnnouncement",
+                0x0D: "MasterAnnouncement",
+                0x0E: "ResetStateRequest",
+                0x0F: "LocalMasterAnnouncement",
+            },
+        ),
     ]
 
     def mysummary(self):
@@ -1135,6 +1140,7 @@ def default_payload_class(self, payload):
 
 # [MS-BRWS] sect 2.2.1
 
+
 class BRWS_HostAnnouncement(BRWS):
     OpCode = 0x01
     fields_desc = [
@@ -1157,6 +1163,7 @@ def mysummary(self):
 
 # [MS-BRWS] sect 2.2.6
 
+
 class BRWS_BecomeBackup(BRWS):
     OpCode = 0x0B
     fields_desc = [
@@ -1170,6 +1177,7 @@ def mysummary(self):
 
 # [MS-BRWS] sect 2.2.10
 
+
 class BRWS_LocalMasterAnnouncement(BRWS_HostAnnouncement):
     OpCode = 0x0F
 
@@ -1193,6 +1201,10 @@ def dispatch_hook(cls, _pkt=None, *args, **kargs):
                 return SMB_Header
             if _pkt[:4] == b"\xfeSMB":
                 return SMB2_Header
+            if _pkt[:4] == b"\xfdSMB":
+                return SMB2_Transform_Header
+            if _pkt[:4] == b"\xfcSMB":
+                return SMB2_Compression_Transform_Header
         return cls