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#1 2015-02-15 03:48 PM

RobSeace
Administrator
From: Boston, MA
Registered: 2002-06-12
Posts: 3,826
Website

Disappearing thread?

Did a thread just disappear from Networking?  I just responded to a new post from justin777 (not the "impacket" one, but a new one), and now it seems to be gone...  WTF?

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#2 2015-02-15 04:01 PM

justin777
Member
Registered: 2015-02-10
Posts: 6

Re: Disappearing thread?

Hi, sorry I deleted that post like last 30 mins because yeah I found out the question is quite stupid and I am just frustrated on my research findings.

I read your answer from my email:
Multicast TCP??  That's just not something that's possible...  TCP requires a one-to-one stream to work...  It can't work one-to-many or many-to-many!
But, I'm failing to even grasp how the code you show is at all related to TCP, since you seem to be trying to send raw ICMPv6 based on the args for socket()...  ICMP is not at all based on TCP, so I'm not sure what you're talking about there...
Also, since you're using an AF_INET6/SOCK_RAW/ICMPv6 socket, you are expected to provide full IPv6 headers and ICMPv6 headers in the message sent, not just a simple string like you're trying to send over the socket now...  That was obviously taken from the UDP-based example...  With a normal UDP socket, you aren't expected to provide headers, so that will work...
But, if this is still related to the other question where you needed to include a VLAN marker in the Ethernet headers, then you still need to be using AF_PACKET/SOCK_RAW sockets rather than AF_INET6/SOCK_RAW...  You won't be able to send Ethernet headers over an AF_INET6 socket...
I'm not seeing where "maddr" gets set in your code...  In the original UDP-based code you link to, it's set to a valid IPv6 multicast address ("ff12::4242", and port 4242)...  This is a link-local multicast address which won't be routed off-LAN...
As for the bind() error, are you sure you're using the assigned IPv6 address of your Ethernet interface?
(On an off-topic side-note, mainly intended for i3839 to read: I just discovered that apparently Comcast has enabled IPv6 on our router!  I was just doing an "ifconfig" and noticed I suddenly have a globally routable IPv6 address now!  Ah, the magic of auto-configuring IPv6...  And, it seemingly works to reach the IPv6 Net at large...  Holy shit!  It's cool and all, but I really wish they would've let us know they were doing it...  Who knows how long I could've been playing around with this!)

Thanks for that.

Technically I was confuse because I want to send a raw packet with VLAN Headers, because I am not sure if I send in a Multicast if it will receive by all computers in the network. If you are interested on my problem, I posted a topic on Network Engineering StackOverflow because my problem now is on logic side of the network

http://networkengineering.stackexchange … g-computer

I will take a break for a while, I am rushing my Thesis because it is almost my deadline and I cant think straight now

Last edited by justin777 (2015-02-15 04:06 PM)

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#3 2015-02-15 04:09 PM

RobSeace
Administrator
From: Boston, MA
Registered: 2002-06-12
Posts: 3,826
Website

Re: Disappearing thread?

Ah, cool...  I just wondered if I or another admin accidently deleted it, or if the database was having problems, or something...

(And, I'm still stoked about finally having true IPv6 access! ;-))

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#4 2015-02-15 04:15 PM

justin777
Member
Registered: 2015-02-10
Posts: 6

Re: Disappearing thread?

Nice, I am in a third world country so no IPv6 for me. hopefully in the future

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#5 2015-02-15 10:00 PM

i3839
Oddministrator
From: Amsterdam
Registered: 2003-06-07
Posts: 2,230

Re: Disappearing thread?

Actually, if you're in a third world country I think the chance of you getting IPv6 sooner that most others is likely because that are probably the countries that don't have enough IPv4 addresss to begin with. But I might be wrong. Lucky you Rob! Although some providers give IPv6 addresses over here, it's mostly a novelty thing.

(Today I deleted one spam post.)

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#6 2015-02-16 02:12 PM

RobSeace
Administrator
From: Boston, MA
Registered: 2002-06-12
Posts: 3,826
Website

Re: Disappearing thread?

It's pretty novel over here, too...  I knew Comcast was rolling out dual-stack setups lots of places, but I hadn't heard anything about it coming to our area...  Plus, I heard they were concentrating on consumer connections rather than business ones (we've got business class Internet, just for the reliability, and lack of any port blocking and other nonsense, and static IPs so we can run servers)...  Now, I'm just wondering how damn long we've had this IPv6 without knowing it!  I suspect it happened a couple weekends ago...  All cable services (Internet, phone, TV) went down for a few hours...  I bet that's when they made the change to the router...  After that, it presumably sent out its multicast router greeting, and my machine must've seen it and auto-generated its own IPv6...  They've only given us a /64 it looks like, but that's plenty for us, anyway...  But, it's no surprise they're giving out the bare minimum they can, despite the recommendations to hand out /48s or /56s to everyone...  In reality, almost no one will have a need for /48, I doubt...  Huge companies, maybe...  For most, a single subnet with 2^64 hosts will be plenty, I suspect... ;-)  If only we could subnet on the lower 64 bits of the address to divide that up further, there would be no need for anyone to get more than a /64...  But, oh well...

[agrajag]$ traceroute6 www.google.com
traceroute to www.google.com (2607:f8b0:4006:80d::1014), 30 hops max, 40 byte packets
1  2601:6:4381:b300::1 (2601:6:4381:b300::1)  0.651 ms  1.511 ms  1.690 ms
2  2001:558:4023:8b::1 (2001:558:4023:8b::1)  10.789 ms  14.608 ms  14.815 ms
3  te-0-1-0-3-sur01.brockton.ma.boston.comcast.net (2001:558:202:22a::1)  14.925 ms  15.008 ms  15.089 ms
4  be-96-ar01.woburn.ma.boston.comcast.net (2001:558:200:1a8::1)  17.398 ms  19.856 ms  18.831 ms
5  * * *
6  he-0-10-0-1-pe04.350ecermak.il.ibone.comcast.net (2001:558:0:f8cd::2)  44.595 ms  37.247 ms  39.127 ms
7  as15169-5-c.350ecermak.il.ibone.comcast.net (2001:559::37a)  38.732 ms  38.941 ms  37.676 ms
8  2001:4860::1:0:84a0 (2001:4860::1:0:84a0)  44.063 ms  46.725 ms 2001:4860::1:0:84b4 (2001:4860::1:0:84b4)  43.909 ms
9  2001:4860::8:0:8458 (2001:4860::8:0:8458)  44.120 ms 2001:4860::8:0:5900 (2001:4860::8:0:5900)  43.556 ms 2001:4860::8:0:833f (2001:4860::8:0:833f)  43.641 ms
10  2001:4860::8:0:4397 (2001:4860::8:0:4397)  42.399 ms  41.384 ms 2001:4860::8:0:4398 (2001:4860::8:0:4398)  39.768 ms
11  2001:4860:0:1::121c (2001:4860:0:1::121c)  40.305 ms  38.320 ms  40.073 ms
12  2001:4860:0:1::121d (2001:4860:0:1::121d)  42.200 ms  41.149 ms  40.498 ms
13  2607:f8b0:4006:80d::f (2607:f8b0:4006:80d::f)  38.848 ms 2607:f8b0:8000:4f::3 (2607:f8b0:8000:4f::3)  36.597 ms 2607:f8b0:4006:80d::f (2607:f8b0:4006:80d::f)  38.496 ms

;-)

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#7 2015-03-27 11:49 AM

RobSeace
Administrator
From: Boston, MA
Registered: 2002-06-12
Posts: 3,826
Website

Re: Disappearing thread?

Hmph...  Since yesterday morning, the IPv6 connectivity has been down, and I've been forced to change "/etc/gai.conf" to give IPv4 priority over IPv6, in order to access a lot of hosts...  I hope it's a temporary thing, but I don't know...  It's not like we can really complain, since they never even announced we had it or advertised it as a feature in the first place...  Dammit, Comcast, I was just starting to think you weren't evil bastards!

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#8 2015-03-28 02:41 PM

RobSeace
Administrator
From: Boston, MA
Registered: 2002-06-12
Posts: 3,826
Website

Re: Disappearing thread?

Whew, thankfully it was only a temporary outage and things are working again today...  I was worried they were just going to yank it away completely, like they made a mistake giving it to us in the first place!

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