Re: netlink socket does not accept SOCK_DGRAM
Date: Mon, 16 Jan 2023 15:13:56 UTC
> On 15 Jan 2023, at 13:09, Alexander V. Chernikov <melifaro@ipfw.ru> wrote:
>
>>
>> On 15 Jan 2023, at 02:26, User Ngor <ihor@antonovs.family> wrote:
>>
>> man 4 rtnetlink says:
>>
>> int socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
>>
>>
>>
>> The following snippet fails
>>
>> int fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
>> if (fd < 0) {
>> perror("Failed to open netlink socket");
>> return -1;
>> }
>> printf("all good\n");
>> close(fd);
>> return 0;
>>
>> I get: Failed to open netlink socket: Protocol wrong type for socket
>>
>>
>> but if I change
>> int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
>>
>> I get "all good"
>>
>> Am I doing something wrong or is this a bug?
> It’s a bug. The manage should state SOCK_RAW, but both options should be supported, which is not the case ATM.
> I’ll fix it in a couple of days.
Raised https://reviews.freebsd.org/D38075 with a fix.
> Meanwhile it may be worth looking into snl(3) which abstracts issues like this one.
>>
>>
>>
>> $ uname -a FreeBSD zen.hq 14.0-CURRENT FreeBSD 14.0-CURRENT #0 main-n259967-11b5b9e8a520: Sat Jan 7 16:39:30 UTC 2023 root@releng1.nyi.freebsd.org:/usr/obj/usr/src/amd64.amd64/sys/GENERIC amd64
>>
>> $ kldstat | grep netl
>> 39 1 0xffffffff839fc000 14af8 netlink.ko
>>
>>
>> --
>> Ihor Antonov