Fix for issue #1199

[polybassa]

No description provided.

[codecov-io]

Codecov Report

Merging #1276 into master will decrease coverage by 5.53%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1276      +/-   ##
==========================================
- Coverage   84.79%   79.25%   -5.54%     
==========================================
  Files         160      159       -1     
  Lines       38322    37544     -778     
==========================================
- Hits        32495    29757    -2738     
- Misses       5827     7787    +1960

Impacted Files	Coverage Δ
scapy/sendrecv.py	40.26% <100%> (-38%)	⬇️
scapy/layers/tls/automaton.py	15.78% <0%> (-64.92%)	⬇️
scapy/arch/pcapdnet.py	12.62% <0%> (-56.15%)	⬇️
scapy/as_resolvers.py	32.07% <0%> (-49.06%)	⬇️
scapy/layers/tls/automaton_srv.py	26.2% <0%> (-45.67%)	⬇️
scapy/layers/tls/automaton_cli.py	31.88% <0%> (-45.15%)	⬇️
scapy/supersocket.py	38.96% <0%> (-40.26%)	⬇️
scapy/modules/nmap.py	57.46% <0%> (-39.56%)	⬇️
scapy/arch/linux.py	36.5% <0%> (-37.37%)	⬇️
... and 41 more

[guedou]

Thanks for the PR. Could you provide unit tests?

For example:

>>> packet = IP(dst="8.8.8.8")/ICMP() ; r = sr(packet); packet.sent_time is not None
>>> packet = IP(dst="8.8.8.8")/ICMP() ; r = sr1(packet); packet.sent_time is not None

[guedou]

It was only examples. Please remove the ';' and add assert before the tests for None. Thanks.

[polybassa]

Sorry

[gpotter2]

Your first proposal list was correct, this one isn’t. A packet may be a generator, a list...

[karpierz]

Why not?:
tobesent = list(pkt) if hasattr(pkt, "__iter__") else pkt

[gpotter2]

I think it's safe to call simply list(pkt):

• if pkt is a list, list() returns the same object
• if pkt is a packet, or a generator, iter is implicitly called

[polybassa]

Now I got a problem. If I do the following:
tobesent = [pkt]
this issue is fixed, but some other unit test will fail.
if I do
tobesent = list(pkt)
this issue is still present, but other unit test will not fail.

[gpotter2]

This means that the fix is incorrect. this line is more complex than it looks, knowing that a packet can generate others depending on its parameters

[karpierz]

I think it's safe to call simply list(pkt):
if pkt is a list, list() returns the same object

It is not quite true.
list(list_object) returns a new list object (copy of list_object). Try:
a = [1,2,3,4]
b = list(a)
a is b

[polybassa]

ok, the problem is probably somewhere inside packet.__iter__

[polybassa]

unfortunately, I don't know enough internals of scapy, to fix this issue

[karpierz]

I will try to help you.
UPDATE: Solved. See at #1282