[FS#656] IPv6 relay mode does not work

Sun Mar 26 14:25:15 PDT 2017

A new Flyspray task has been opened.  Details are below. 

User who did this - Matt Longbrake (mlongbrake) 

Attached to Project - LEDE Project
Summary - IPv6 relay mode does not work
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Medium
Priority - Very Low
Reported Version - lede-17.01
Due in Version - Undecided
Due Date - Undecided
Details - My ISP does not support DHCPv6, so I need to use IPv6 relay mode to enable my devices to obtain IPv6 addresses via SLAAC.  I have configured relay mode as indicated in the documentation on a HooToo TM-02 for the time being.  If I can get all this to work I will upgrade to a more capable device.

Running tcpdump on the WLAN interface I can see the router solicitation requests coming from my clients.  When I run tcpdump on the WAN interface I don't see any router solicitations and, therefore, no router advertisements coming back from my ISP modem.  The router itself gets an address from the modem, but the relaying of requests from clients is not happening.

I have posted my config files below, but they are basically stock.  Is this a problem with the DHCPv6 server or some kind of firewall problem preventing the requests from getting out?

/etc/config/network:

config interface 'loopback'
	option ifname 'lo'
	option proto 'static'
	option ipaddr '127.0.0.1'
	option netmask '255.0.0.0'

config globals 'globals'
	option ula_prefix 'fd20:0787:2c66::/48'

config interface 'lan'
	option proto 'static'
	option ipaddr '192.168.1.1'
	option netmask '255.255.255.0'
	option _orig_ifname 'eth0'
	option _orig_bridge 'false'
	option ip6assign '64'

config device 'lan_dev'
	option name 'eth0'
	option macaddr '00:1c:c2:13:6f:05'

config switch
	option name 'switch0'
	option reset '1'
	option enable_vlan '0'

config interface 'wan'
	option proto 'dhcp'
	option ifname 'eth0'

config interface 'wan6'
	option proto 'dhcpv6'
	option ifname 'eth0'
	option reqaddress 'try'
	option reqprefix 'auto'

/etc/config/dhcp:

config dnsmasq
	option domainneeded '1'
	option boguspriv '1'
	option filterwin2k '0'
	option localise_queries '1'
	option rebind_protection '1'
	option rebind_localhost '1'
	option local '/lan/'
	option domain 'lan'
	option expandhosts '1'
	option nonegcache '0'
	option authoritative '1'
	option readethers '1'
	option leasefile '/tmp/dhcp.leases'
	option resolvfile '/tmp/resolv.conf.auto'
	option localservice '1'

config dhcp 'lan'
	option interface 'lan'
	option start '100'
	option limit '150'
	option leasetime '12h'
	option dhcpv6 'relay'
	option ra 'relay'
	option ndp 'relay'

config dhcp 'wan'
	option interface 'wan'
	option ignore '1'

config dhcp 'wan6'
	option dhcpv6 'relay'
	option ra 'relay'
	option ndp 'relay'
	option master '1'

config odhcpd 'odhcpd'
	option maindhcp '0'
	option leasefile '/tmp/hosts/odhcpd'
	option leasetrigger '/usr/sbin/odhcpd-update'

/etc/config/firewall:

config defaults
	option syn_flood '1'
	option input 'ACCEPT'
	option output 'ACCEPT'
	option forward 'REJECT'

config zone
	option name 'lan'
	list network 'lan'
	option input 'ACCEPT'
	option output 'ACCEPT'
	option forward 'ACCEPT'

config zone
	option name 'wan'
	list network 'wan'
	list network 'wan6'
	option input 'REJECT'
	option output 'ACCEPT'
	option forward 'REJECT'
	option masq '1'
	option mtu_fix '1'

config forwarding
	option src 'lan'
	option dest 'wan'

config rule
	option name 'Allow-DHCP-Renew'
	option src 'wan'
	option proto 'udp'
	option dest_port '68'
	option target 'ACCEPT'
	option family 'ipv4'

config rule
	option name 'Allow-Ping'
	option src 'wan'
	option proto 'icmp'
	option icmp_type 'echo-request'
	option family 'ipv4'
	option target 'ACCEPT'

config rule
	option name 'Allow-IGMP'
	option src 'wan'
	option proto 'igmp'
	option family 'ipv4'
	option target 'ACCEPT'

config rule
	option name 'Allow-DHCPv6'
	option src 'wan'
	option proto 'udp'
	option src_ip 'fc00::/6'
	option dest_ip 'fc00::/6'
	option dest_port '546'
	option family 'ipv6'
	option target 'ACCEPT'

config rule
	option name 'Allow-MLD'
	option src 'wan'
	option proto 'icmp'
	option src_ip 'fe80::/10'
	list icmp_type '130/0'
	list icmp_type '131/0'
	list icmp_type '132/0'
	list icmp_type '143/0'
	option family 'ipv6'
	option target 'ACCEPT'

config rule
	option name 'Allow-ICMPv6-Input'
	option src 'wan'
	option proto 'icmp'
	list icmp_type 'echo-request'
	list icmp_type 'echo-reply'
	list icmp_type 'destination-unreachable'
	list icmp_type 'packet-too-big'
	list icmp_type 'time-exceeded'
	list icmp_type 'bad-header'
	list icmp_type 'unknown-header-type'
	list icmp_type 'router-solicitation'
	list icmp_type 'neighbour-solicitation'
	list icmp_type 'router-advertisement'
	list icmp_type 'neighbour-advertisement'
	option limit '1000/sec'
	option family 'ipv6'
	option target 'ACCEPT'

config rule
	option name 'Allow-ICMPv6-Forward'
	option src 'wan'
	option dest '*'
	option proto 'icmp'
	list icmp_type 'echo-request'
	list icmp_type 'echo-reply'
	list icmp_type 'destination-unreachable'
	list icmp_type 'packet-too-big'
	list icmp_type 'time-exceeded'
	list icmp_type 'bad-header'
	list icmp_type 'unknown-header-type'
	option limit '1000/sec'
	option family 'ipv6'
	option target 'ACCEPT'

config include
	option path '/etc/firewall.user'

config rule
	option src 'wan'
	option dest 'lan'
	option proto 'esp'
	option target 'ACCEPT'

config rule
	option src 'wan'
	option dest 'lan'
	option dest_port '500'
	option proto 'udp'
	option target 'ACCEPT'

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=656