Add TCP_server

[Maxmawt]

Add a TCP server as requested in #2083.

The server completes the 3way handshake by sending the SA and checking the receive of the resulting ack.

For unit testing, I thought adding it in the same file that the ones for the TCP_client but it did not find them.

[codecov]

Codecov Report

Merging #2409 into master will increase coverage by 0.23%.
The diff coverage is 42.85%.

@@            Coverage Diff            @@
##           master   #2409      +/-   ##
=========================================
+ Coverage   87.37%   87.6%   +0.23%     
=========================================
  Files         242     242              
  Lines       50656   50739      +83     
=========================================
+ Hits        44261   44452     +191     
+ Misses       6395    6287     -108

Impacted Files	Coverage Δ
scapy/layers/inet.py	71.25% <42.85%> (-1.89%)	⬇️
scapy/utils6.py	87.24% <0%> (+0.45%)	⬆️
scapy/arch/pcapdnet.py	70.7% <0%> (ø)	⬆️
scapy/autorun.py	82.64% <0%> (+4.13%)	⬆️
scapy/arch/bpf/core.py	87.25% <0%> (+5.88%)	⬆️
scapy/arch/common.py	89.39% <0%> (+13.63%)	⬆️
scapy/layers/dhcp6.py	85.75% <0%> (+21.51%)	⬆️
scapy/arch/bpf/supersocket.py	75.44% <0%> (-1.34%)	⬇️

[gpotter2]

Thanks for the PR !

You should make TCP_server a subclass of TCP_client, or a common parent. This way, each time a function is exactly the same in both, you don't have copy paste it. This will make things cleaner

[gpotter2]

closed for inactivity