I have OpenWrt running on a raspberry pi 3 and need to be able to configure the IPv6 address lease options.

The main configuration options I'm looking for are:
1) IPv6 Lease Type (Disabled / SLAAC + Stateless DHCPv6 / Stateful DHCPv6)
2) Lease Duration
3) LAN IPv6 Address
4) IPv6 Gateway Address

I have an old D-Link DIR-825 which has all of this configurability, and am looking to use the raspberry pi as a replacement if these options are configurable.

The Network->DHCP and DNS panel in OpenWrt's web interface doesn't have options like I need. Is there some other way that this functionality can be configured?

You can edit most of those settings for each interface in Network->Interfaces.

If you are running odhcpd as part of OpenWRT, it allows you to set up lease times:

https://github.com/sbyx/odhcpd

Yes odhcpd is in our build, but it seems the options that we need are just not presented in the web interface.

Our use case requires convenient editing of the configuration via the web interface, so unfortunately modifying config files by hand won't suffice.

Thanks for the replies! It's starting to look like the configuration options we need are available to be configured by hand in config files, but apparently there's no way (yet) to do this conveniently via the web interface.

That's unfortunate, since LuCI doesn't support all configuration on OpenWRT. Perhaps you may want to make a request to the LuCI devs.