IPv6 support

[jg1uaa]

Hello,

Current code is strongly dependent on sockaddr_in and limited to IPv4 support.
I am trying to rewrite with sockaddr_storage to add IPv6 support.
There is a modified code at https://github.com/jg1uaa/DAPNETGateway and tested with MMDVM-POCSAG emulator http://www.uaa.org.uk/gomitext/2019/20190923/fakemmdvmhost-pocsag.c
At least they looks working on Linux/OpenBSD (Windows and MacOS not tested), I hope they will be a hint to future expansion of DAPNETGateway/MMDVMHost.

[g4klx]

I like it! I haven't spent much time looking at IPv6, my fault. If it's that simple then it needs to be rolled out into the whole suite of MMDVM programs for future proofing. You're code looks good.

[jg1uaa]

Changed some lines for Windows/VisualStudio 2019. No problem for compiling
but not tested yet.

Current code does not have IPv4<-->IPv6 fallback. Do we have to implement
this function? At least there is no need to with using IP address directly
like XLX/BrandMeister.

If there is no problem, I want to issue pull-request. But is there any
development (experimental) branch?

[phl0]

I have added an "IPv6" branch for testing purposes.

[jg1uaa]

Now I issuing pull request to IPv6 branch.
I uploaded MMDVM-POCSAG emulator to https://github.com/jg1uaa/fakemmdvmhost-pocsag and IPv6 capable XLX reflector to https://github.com/jg1uaa/xlxd .

[phl0]

@jg1uaa I did compile the IPv6 branch successfully but get a TCP error 97 when trying to use an IPv6 address in DAPNETGateway.ini. Is there any format we need to have in the .ini? Using a domain name yields the same result ... :(

[jg1uaa]

@phl0 this is my DAPNETGateway.ini

[General]
Callsign=jg1uaa
#WhiteList=12345,78901
#BlackList=
#BlacklistRegexfile=/tmp/blregexes.txt
#WhitelistRegexfile=/tmp/wlregexes.txt
RptAddress=::1
RptPort=3800
LocalAddress=::1
LocalPort=4800
Daemon=0

[Log]
# Logging levels, 0=No logging
DisplayLevel=1
FileLevel=1
FilePath=.
FileRoot=DAPNETGateway

[DAPNET]
Address=dapnet.afu.rwth-aachen.de
Port=43434
AuthKey=************
Debug=0

dapnet.afu.rwth-aachen.de has IPv4 address only.
If you use other (IPv6-capable) server, please tell me.

[phl0]

Jepp, I have an own instance of DAPNET running on my own server. That is IPv6 capable and the core process listens on IPv6 socket. I did try with that host.
Let me know if I should give you access to that and how I can supply you with credentials..

[jg1uaa]

@phl0 oh, it is bug of TCPSocket.cpp. It always creates IPv4 socket...
I uploaded fixed code to my repo, please test this code jg1uaa@8af07c3
If there is no problem I will issue pull request.

[phl0]

@jg1uaa roger that. Just tested successfully. Go ahead an PR that. My DAPNETGateway is noch connected to my test instance using IPv6: