From c92fb3da1ce6f7b003c165bd3352d8c804e978c0 Mon Sep 17 00:00:00 2001
From: Pierre LALET <pierre.lalet@cea.fr>
Date: Sat, 21 Jan 2017 14:34:40 +0100
Subject: [PATCH] Handle FlagValue fields changes with .raw_packet_cache
---
scapy/fields.py | 9 +++++++++
scapy/packet.py | 2 +-
test/regression.uts | 24 ++++++++++++++++++++++++
3 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/scapy/fields.py b/scapy/fields.py
index cecd8761..d4e5f4ca 100644
--- a/scapy/fields.py
+++ b/scapy/fields.py
@@ -26,6 +26,7 @@ class Field(object):
__slots__ = ["name", "fmt", "default", "sz", "owners"]
__metaclass__ = Field_metaclass
islist = 0
+ ismutable = False
holds_packets = 0
def __init__(self, name, default, fmt="H"):
self.name = name
@@ -1008,6 +1009,8 @@ class FlagValue(object):
self.value &= ~(2 ** self.names.index(attr))
else:
return super(FlagValue, self).__setattr__(attr, value)
+ def copy(self):
+ return self.__class__(self.value, self.names)
class FlagsField(BitField):
@@ -1031,6 +1034,7 @@ class FlagsField(BitField):
:param size: number of bits in the field
:param names: (list or dict) label for each flag, Least Significant Bit tag's name is written first
"""
+ ismutable = True
__slots__ = ["multi", "names"]
def __init__(self, name, default, size, names):
self.multi = isinstance(names, list)
@@ -1041,6 +1045,11 @@ class FlagsField(BitField):
return type(x)(None if v is None else FlagValue(v, self.names)
for v in x)
return None if x is None else FlagValue(x, self.names)
+ def m2i(self, pkt, x):
+ if isinstance(x, (list, tuple)):
+ return type(x)(None if v is None else FlagValue(v, self.names)
+ for v in x)
+ return None if x is None else FlagValue(x, self.names)
def i2repr(self, pkt, x):
if isinstance(x, (list, tuple)):
return repr(type(x)(
diff --git a/scapy/packet.py b/scapy/packet.py
index e2935ddb..9a6d73ec 100644
--- a/scapy/packet.py
+++ b/scapy/packet.py
@@ -589,7 +589,7 @@ Creates an EPS file describing a packet. If filename is not provided a temporary
s, fval = f.getfield(self, s)
# We need to track fields with mutable values to discard
# .raw_packet_cache when needed.
- if f.islist or f.holds_packets:
+ if f.islist or f.holds_packets or f.ismutable:
self.raw_packet_cache_fields[f.name] = f.do_copy(fval)
self.fields[f.name] = fval
assert(raw.endswith(s))
diff --git a/test/regression.uts b/test/regression.uts
index 393df949..b87cfb8a 100644
--- a/test/regression.uts
+++ b/test/regression.uts
@@ -7532,3 +7532,27 @@ assert not any(getattr(pkt.flags, f) for f in 'FSRECN')
pkt.flags = 50
assert all(getattr(pkt.flags, f) for f in 'SAU')
assert not any(getattr(pkt.flags, f) for f in 'FRPECN')
+
+= Flag values mutation with .raw_packet_cache
+~ IP TCP
+
+pkt = IP(str(IP(flags="MF")/TCP(flags="SA")))
+assert pkt.raw_packet_cache is not None
+assert pkt[TCP].raw_packet_cache is not None
+assert pkt.flags.MF
+assert not pkt.flags.DF
+assert not pkt.flags.evil
+assert pkt[TCP].flags.S
+assert pkt[TCP].flags.A
+assert not any(getattr(pkt[TCP].flags, f) for f in 'FRPUECN')
+pkt.flags.MF = 0
+pkt.flags.DF = 1
+pkt[TCP].flags.U = True
+pkt[TCP].flags.S = False
+pkt = IP(str(pkt))
+assert not pkt.flags.MF
+assert pkt.flags.DF
+assert not pkt.flags.evil
+assert pkt[TCP].flags.A
+assert pkt[TCP].flags.U
+assert not any(getattr(pkt[TCP].flags, f) for f in 'FSRPECN')
--
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