Fix IPv6 for domain names #4
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| if self.use_udp: | ||
| s.send(b'') | ||
| s.sendto(b'', socket_address) |
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Just tested and received the following error. I'm investigating, but sharing in case you have any immediate insight:
C:\Users\martin\Desktop>knock.py -u ipv6.netconfigs.com 12345
Traceback (most recent call last):
File "C:\Users\martin\Desktop\knock.py", line 68, in <module>
Knocker(sys.argv[1:]).knock()
File "C:\Users\martin\Desktop\knock.py", line 56, in knock
s.sendto(b'', socket_address)
OSError: [WinError 10057] A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied
C:\Users\martin\Desktop>
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Yes, of course, second argument is flags, try putting None as second argument ... Strange thing is that on my system it didn't throw the error. The socket implementations are really strangely inconsistent.
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Oh, now I see that it's possible to pass just the address ... well, try passing the None - maybe it's a Windows-thing
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Got it: self.address_family, self.socket_type, _, _, socket_address = socket.getaddrinfo(
host=args.host,
port=None,
- type=0,
+ type=socket.SOCK_DGRAM if self.use_udp else socket.SOCK_STREAM,
- proto=socket.IPPROTO_UDP if self.use_udp else socket.IPPROTO_TCP,
+ proto=0,
flags=socket.AI_ADDRCONFIG
)[0] |
| host=args.host, | ||
| port=None, | ||
| type=0, | ||
| proto=socket.IPPROTO_UDP if self.use_udp else socket.IPPROTO_TCP, |
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should be
type=socket.SOCK_DGRAM if self.use_udp else socket.SOCK_STREAM,
proto=0,There was a problem hiding this comment.
Yep, I actually spend a few minutes thinking about those two ... what's the difference? To me it looked like proto is kind of more general or something like that ... but I'm not really sure and obviously it matters a lot.
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The type and proto inputs to socket.getaddrinfo() seem to emerg as items 2 and 3 in the tuple. Not sure they affect anything else, but the call to socket.socket() need the SOCK_DGRAM or SOCK_STREAM to create the right type. As you passed in type=0 to socket.getaddrino(), that was arriving at socket.socket() and like creating a SOCK_STREAM by default,
BTW, I'm testing on Windows 10 Python 3.5.2 against a CentOS6 linux and using tcpdump to verify the packet arrival.
My server has 3 types of addresses, IPv4, IPv6 and 6to4 (a transition variant of IPv6):
- ipv4.netconfigs.com
- ipv6.netconfigs.com
- 6to4.netconfigs.com
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Strange ... alright, I changed it to filter by type instead - I'm happy that it works for you. Thank you very much for the thorough testing :)
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I've just done a full matrix of tests of my two line fix suggestion:
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Resolves #3