On 8/6/20 2:55 AM, Xin Long wrote:
> On Thu, Aug 6, 2020 at 10:50 AM Hideaki Yoshifuji
> <hideaki.yoshif...@miraclelinux.com> wrote:
>>
>> Hi,
>>
>> 2020年8月4日(火) 0:35 Xin Long <lucien....@gmail.com>:
>>>
>>> This is to add an ip_dev_find like function for ipv6, used to find
>>> the dev by saddr.
>>>
>>> It will be used by TIPC protocol. So also export it.
>>>
>>> Signed-off-by: Xin Long <lucien....@gmail.com>
>>> ---
>>> include/net/addrconf.h | 2 ++
>>> net/ipv6/addrconf.c | 39 +++++++++++++++++++++++++++++++++++++++
>>> 2 files changed, 41 insertions(+)
>>>
>>> diff --git a/include/net/addrconf.h b/include/net/addrconf.h
>>> index 8418b7d..ba3f6c15 100644
>>> --- a/include/net/addrconf.h
>>> +++ b/include/net/addrconf.h
>>> @@ -97,6 +97,8 @@ bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
>>>
>>> int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev);
>>>
>>> +struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr
>>> *addr);
>>> +
>>
>> How do we handle link-local addresses?
> This is what "if (!result)" branch meant to do:
>
> + if (!result) {
> + struct rt6_info *rt;
> +
> + rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
> + if (rt) {
> + dev = rt->dst.dev;
> + ip6_rt_put(rt);
> + }
> + } else {
> + dev = result->idev->dev;
> + }
>
the stated purpose of this function is to find the netdevice to which an
address is attached. A route lookup should not be needed. Walking the
address hash list finds the address and hence the netdev or it does not.
