Re: netlink socket does not accept SOCK_DGRAM

> On 16 Jan 2023, at 15:13, Alexander V. Chernikov <melifaro@ipfw.ru> wrote:
> 
> 
> 
>> 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.
Committed as 0079d177ab69.
>> 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