Re: Openbsd 5.7: IPv6 autoconf not working
Em 18-08-2015 23:34, Alexandre Westfahl escreveu:
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
This seems odd to me. It looks like the packet is mangled. I can see the
multicast address, the link-local address. But I don't see any valid
global prefixes. Check your card and cables?
I have on my settings sheet the DNS and the prefix I'm delegated.
You know if this router advertises the DNS through SLAAC? It doesn't
seem to be the case.
I tried wide dhcpv6 and it works but I would like if possible to go without
it.
The modem brand is Huawei but i don't have the model here.
I have a huawei here, and it works both through SLAAC and DHCPv6. But,
there is a catch. My ISP can remotely configure which LAN ports works
and which doesn't. In mine, only the 3 first ethernet ports work, the
remaining doesn't. Check if you're using the first port, try changing
them. And ask your provider to enable the other ports if it doesn't.
Cheers,
Giancarlo Razzolini
Re: Openbsd 5.7: IPv6 autoconf not working
On Wed, Aug 19, 2015 at 10:54 PM, Giancarlo Razzolini grazzol...@gmail.com
wrote:
Em 18-08-2015 23:34, Alexandre Westfahl escreveu:
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
This seems odd to me. It looks like the packet is mangled. I can see the
multicast address, the link-local address. But I don't see any valid
global prefixes. Check your card and cables?
âMy card and cable are doing well since I have no problem on IPv4 and
IPv6
works if I use wide DHCPv6.
â
I have on my settings sheet the DNS and the prefix I'm delegated.
You know if this router advertises the DNS through SLAAC? It doesn't
seem to be the case.
âit doesn't seems to but â
âI have the information so I can set it in resolv.conf if needed.
â
I tried wide dhcpv6 and it works but I would like if possible to go
without
it.
The modem brand is Huawei but i don't have the model here.
I have a huawei here, and it works both through SLAAC and DHCPv6. But,
there is a catch. My ISP can remotely configure which LAN ports works
and which doesn't. In mine, only the 3 first ethernet ports work, the
remaining doesn't. Check if you're using the first port, try changing
them. And ask your provider to enable the other ports if it doesn't.
âThe first port is the main one I have to use according to their request
so the port is not faulty. I'm starting to think that they have a
implemented advertisement system which makes dhcpv6 compulsory...â
âThanks,
Alexâ
Cheers,
Giancarlo Razzolini
Re: Openbsd 5.7: IPv6 autoconf not working
On 18/08/15(Tue) 10:41, Alexandre Westfahl wrote: Hi, Thank you for your explanations. I activated debug but don't get any output anywhere. Since I couldn't find anything, I tried a global grep but without success (cat /var/log/* |grep inet6 and ipv6). Since my tcpdump result are not changed, it means I have to install dhcpv6client? I need the wide one or another one? No idea, maybe someone else can share her/his experience. M.
Re: Openbsd 5.7: IPv6 autoconf not working
Em 17-08-2015 22:41, Alexandre Westfahl escreveu: I activated debug but don't get any outputâ anywhere. Since I couldn't find anything, I tried a global grep but without success (cat /var/log/* |grep inet6 and ipv6). Kernel messages will appear on /var/log/messages, IIRC. And on dmesg and on the console. So I guess that, if there was any, you'd see them. Since my tcpdump result are not changed, it means I have to install dhcpv6client? I need the wide one or another one? Can you try to capture the whole packet? Try setting a snaplen of 1500. I believe it is too early to give up on SLAAC. But you might need DHCPv6 anyway, if your router don't advertise the dns servers. See if you ain't getting malformed packets from the router, or if it's advertising, but with no actual prefixes/routes. Per RFC 7084 [0], a router should stop advertising when it doesn't have global IPv6 connectivity. But, not every manufacturer is fond of RFC's. Cheers, Giancarlo Razzolini [0] https://tools.ietf.org/html/rfc7084
Re: Openbsd 5.7: IPv6 autoconf not working
@Michael: I deactivate PF to make my tests (I want to have IPv6 working
before I think of fw rules)
@Giancarlo: yes, I have no log even with debug
Please find below the new tcpdump:
11:25:26.017135 fe80::200:24ff:fed1:86bc ff02::2: icmp6: router
solicitation (src lladdr: 00:00:24:d1:86:bc) [icmp6 cksum ok] (len 16, hlim
255)
6000 0010 3aff fe80
0200 24ff fed1 86bc ff02
0002 8500 2413
0101 24d1 86bc
11:25:26.031216 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO
router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr:
fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32,
hlim 255)
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
11:26:00.025990 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO
router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr:
fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32,
hlim 255)
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
11:26:04.025295 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO
router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr:
fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32,
hlim 255)
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
11:26:26.016515 fe80::200:24ff:fed1:86bc ff02::2: icmp6: router
solicitation (src lladdr: 00:00:24:d1:86:bc) [icmp6 cksum ok] (len 16, hlim
255)
6000 0010 3aff fe80
0200 24ff fed1 86bc ff02
0002 8500 2413
0101 24d1 86bc
11:26:26.022949 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO
router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr:
fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32,
hlim 255)
6c00 0020 3aff fe80
0001 ff02
0001 8600 fa6d 40c0 0708
0101 fc48 efc3 41fe
0501 05dc
Can you try to capture the whole packet? Try setting a snaplen of 1500. I
believe it is too early to give up on SLAAC. But you might need DHCPv6
anyway, if your router don't advertise the dns servers. See if you ain't
getting malformed packets from the router, or if it's advertising, but with
no actual prefixes/routes. Per RFC 7084 [0], a router should stop
advertising when it doesn't have global IPv6 connectivity. But, not every
manufacturer is fond of RFC's.
I have on my settings sheet the DNS and the prefix I'm delegated.
I tried wide dhcpv6 and it works but I would like if possible to go without
it.
The modem brand is Huawei but i don't have the model here.
Thanks,
Alex
On Wed, Aug 19, 2015 at 2:26 AM, Giancarlo Razzolini grazzol...@gmail.com
wrote:
Em 17-08-2015 22:41, Alexandre Westfahl escreveu:
I activated debug but don't get any outputââ¬â¹ anywhere. Since I
couldn't find
anything, I tried a global grep but without success (cat */var/log/**
|grep
inet6 and ipv6).
Kernel messages will appear on /var/log/messages, IIRC. And on dmesg and
on the console. So I guess that, if there was any, you'd see them.
Since my tcpdump result are not changed, it means I have to install
dhcpv6client? I need the wide one or another one?
Can you try to capture the whole packet? Try setting a snaplen of 1500. I
believe it is too early to give up on SLAAC. But you might need DHCPv6
anyway, if your router don't advertise the dns servers. See if you ain't
getting malformed packets from the router, or if it's advertising, but with
no actual prefixes/routes. Per RFC 7084 [0], a router should stop
advertising when it doesn't have global IPv6 connectivity. But, not every
manufacturer is fond of RFC's.
Cheers,
Giancarlo Razzolini
[0] https://tools.ietf.org/html/rfc7084
Re: Openbsd 5.7: IPv6 autoconf not working
Alexandre Westfahl wrote: I have a problem with IPv6, I'm not getting public IP but router advertisement/solicitations are being exchanged. Are you sure pf isn't interfering? What does your pf.conf look like? I've had that problem in the past with IPv6.
Re: Openbsd 5.7: IPv6 autoconf not working
On 17/08/15(Mon) 15:55, Alexandre Westfahl wrote: Hello, I have a problem with IPv6, I'm not getting public IP but router advertisement/solicitations are being exchanged. My interface has following configuration: # ifconfig em0 em0: flags=208843UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,*AUTOCONF6* mtu 1500 lladdr 00:0*86:bc priority: 0 groups: egress media: Ethernet 1000baseT (1000baseT full-duplex) status: active inet 118.192 netmask 0xff80 broadcast 118.*255 *inet6* fe80::200:24**86bc%em0 prefixlen 64 scopeid 0x1 and tcpdump gives below output: Are you stripping NDP options (prefix info) from this output? If not, you can try bumping net.inet6.icmp6.nd6_debug and see if you get any useful info in syslog. tcpdump -vvnli em0 icmp6 05:09:27.184840 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO ^^ Otherwise it might be that your router only sends you advertisement to tell you to use DHCPv6. router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr: fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32, hlim 255)
Re: Openbsd 5.7: IPv6 autoconf not working
âHi, Thank you for your explanations. I activated debug but don't get any outputâ anywhere. Since I couldn't find anything, I tried a global grep but without success (cat /var/log/* |grep inet6 and ipv6). Since my tcpdump result are not changed, it means I have to install dhcpv6client? I need the wide one or another one? Thanks, Alex On Mon, Aug 17, 2015 at 11:23 PM, Martin Pieuchot m...@openbsd.org wrote: On 17/08/15(Mon) 21:42, Alexandre Westfahl wrote: Hi Martin, It's just an ifconfig with char replacement with *. Is NDP available in 5.7? Sorry if I was unclear, I was talking about the tcpdump output. For example: 15:56:41.186643 fe80::ce05:23ff:feac:4e39 ff02::1: icmp6: router advertisement(chlim=255, O router_ltime=1800, reachable_time=0, retrans_time=0)(prefix info: LA valid_ltime=7200, preferred_ltime=3600, prefix=fd00::/64)[ndp opt] (len 88, hlim 255) See the [ndp opt] part? That means that the output of this RA is truncated. In your dump there's a MTU and a Source lladdr option: router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr: fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32, hlim 255) So I justed wanted to know if you edited the output or not :) For the router part, I have in tcpdump advertisement and sollicitation so it should work out of the box no? I also disabled pf to be sure there is no impact. Did you increase net.inet6.icmp6.nd6_debug and see if you've got any error? What do you mean for the router part? Are you configuring the router sending advertisements too? My guess is that your router does not include any prefix information in it's advertisement which would explain why you do not get any address. This is coherent why the 'M' bit set in the advertisement which indicates that address configuration should be retrieve via a stateful protocol (DHCPv6). Martin
Re: Openbsd 5.7: IPv6 autoconf not working
On 17/08/15(Mon) 21:42, Alexandre Westfahl wrote: Hi Martin, It's just an ifconfig with char replacement with *. Is NDP available in 5.7? Sorry if I was unclear, I was talking about the tcpdump output. For example: 15:56:41.186643 fe80::ce05:23ff:feac:4e39 ff02::1: icmp6: router advertisement(chlim=255, O router_ltime=1800, reachable_time=0, retrans_time=0)(prefix info: LA valid_ltime=7200, preferred_ltime=3600, prefix=fd00::/64)[ndp opt] (len 88, hlim 255) See the [ndp opt] part? That means that the output of this RA is truncated. In your dump there's a MTU and a Source lladdr option: router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr: fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32, hlim 255) So I justed wanted to know if you edited the output or not :) For the router part, I have in tcpdump advertisement and sollicitation so it should work out of the box no? I also disabled pf to be sure there is no impact. Did you increase net.inet6.icmp6.nd6_debug and see if you've got any error? What do you mean for the router part? Are you configuring the router sending advertisements too? My guess is that your router does not include any prefix information in it's advertisement which would explain why you do not get any address. This is coherent why the 'M' bit set in the advertisement which indicates that address configuration should be retrieve via a stateful protocol (DHCPv6). Martin
Re: Openbsd 5.7: IPv6 autoconf not working
Hi Martin, It's just an ifconfig with char replacement with *. Is NDP available in 5.7? For the router part, I have in tcpdump advertisement and sollicitation so it should work out of the box no? I also disabled pf to be sure there is no impact. Alex On Mon, Aug 17, 2015 at 6:31 PM, Martin Pieuchot m...@openbsd.org wrote: On 17/08/15(Mon) 15:55, Alexandre Westfahl wrote: Hello, I have a problem with IPv6, I'm not getting public IP but router advertisement/solicitations are being exchanged. â â âMy interface has following configuration: â # ifconfig em0 em0: flags=208843UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,*AUTOCONF6* mtu 1500 lladdr 00:0*86:bc priority: 0 groups: egress media: Ethernet 1000baseT (1000baseT full-duplex) status: active inet 118.192 netmask 0xff80 broadcast 118.*255 *inet6* fe80::200:24**86bc%em0 prefixlen 64 scopeid 0x1 â âand â tcpdump gives below output: Are you stripping NDP options (prefix info) from this output? If not, you can try bumping net.inet6.icmp6.nd6_debug and see if you get any useful info in syslog. tcpdump -vvnli em0 icmp6 05:09:27.184840 fe80::1 ff02::1: icmp6: router advertisement(chlim=64, MO ^^ Otherwise it might be that your router only sends you advertisement to tell you to use DHCPv6. router_ltime=1800, reachable_time=0, retrans_time=0)(src lladdr: fc:48:ef:c3:41:fe)(mtu: mtu=1500) [icmp6 cksum ok] [class 0xc0] (len 32, hlim 255)
Re: Openbsd 5.7: IPv6 autoconf not working
On Mon, Aug 17, 2015 at 03:55:09PM +0900, Alexandre Westfahl wrote: Hello, I have a problem with IPv6, I'm not getting public IP but router advertisement/solicitations are being exchanged. I believe your problem is that OpenBSD 5.7 does not accept router advertisements (RA) if IPv6 forwarding is enabled. Do you have IPv6 forwarding enabled? Before 5.7, acceptance of RA was controlled by a single flag which affected all interfaces. So accepting RA on a router was dangerous since RAs are not authenticated and change the routing tables. OpenBSD 5.7 moved to a AUTOCONF6 flag per interface. The second change you need, which is to accept RA with forwarding enabled, was committed after 5.7. So please try again with a -current snapshot which at the moment is pretty close to what 5.8 will be.
Re: Openbsd 5.7: IPv6 autoconf not working
Hello, Forwarding is not enabled, I have the following sysctl extract: # sysctl |grep inet6 net.inet6.ip6.forwarding=0 net.inet6.ip6.redirect=0 net.inet6.ip6.hlim=64 net.inet6.ip6.mrtproto=103 net.inet6.ip6.maxfragpackets=200 net.inet6.ip6.log_interval=5 net.inet6.ip6.hdrnestlimit=10 net.inet6.ip6.dad_count=1 net.inet6.ip6.auto_flowlabel=1 net.inet6.ip6.defmcasthlim=1 net.inet6.ip6.use_deprecated=1 net.inet6.ip6.rr_prune=5 net.inet6.ip6.v6only=1 net.inet6.ip6.maxfrags=200 net.inet6.ip6.mforwarding=0 net.inet6.ip6.multipath=0 net.inet6.ip6.multicast_mtudisc=0 net.inet6.ip6.neighborgcthresh=2048 net.inet6.ip6.maxifprefixes=16 net.inet6.ip6.maxifdefrouters=16 net.inet6.ip6.maxdynroutes=4096 net.inet6.ip6.dad_pending=0 net.inet6.ip6.mtudisctimeout=600 net.inet6.ip6.ifq.len=0 net.inet6.ip6.ifq.maxlen=256 net.inet6.ip6.ifq.drops=0 net.inet6.icmp6.redirtimeout=600 net.inet6.icmp6.nd6_prune=1 net.inet6.icmp6.nd6_delay=5 net.inet6.icmp6.nd6_umaxtries=3 net.inet6.icmp6.nd6_mmaxtries=3 net.inet6.icmp6.errppslimit=100 net.inet6.icmp6.nd6_maxnudhint=0 net.inet6.icmp6.mtudisc_hiwat=1280 net.inet6.icmp6.mtudisc_lowat=256 net.inet6.icmp6.nd6_debug=0 net.inet6.divert.recvspace=65636 net.inet6.divert.sendspace=65636 Thanks, Alex On Mon, Aug 17, 2015 at 4:15 PM, Stefan Sperling s...@stsp.name wrote: On Mon, Aug 17, 2015 at 03:55:09PM +0900, Alexandre Westfahl wrote: Hello, I have a problem with IPv6, I'm not getting public IP but router advertisement/solicitations are being exchanged. I believe your problem is that OpenBSD 5.7 does not accept router advertisements (RA) if IPv6 forwarding is enabled. Do you have IPv6 forwarding enabled? Before 5.7, acceptance of RA was controlled by a single flag which affected all interfaces. So accepting RA on a router was dangerous since RAs are not authenticated and change the routing tables. OpenBSD 5.7 moved to a AUTOCONF6 flag per interface. The second change you need, which is to accept RA with forwarding enabled, was committed after 5.7. So please try again with a -current snapshot which at the moment is pretty close to what 5.8 will be.
