2 sent pkts have tag for vlan 10 & 20, one should be received on socket created on eth1.10 and another on socket for eth1.20. But it doesn't happen

bobby

12/25/22, 1:57 AM

The packets sent with vlan tag 10 & 20 are received on both sockets. Why I am receiving 4 packets while only 2 packets were sent and also all received packets are untagged (without vlan tag)? What might be the issue?

here is the relevant code: Create: sock = socket(AF_PACKET, SOCK_RAW, htons(MY_ETHTYPE));

memset(&if_opts, 0, sizeof(if_opts));
strncpy(if_opts.ifr_name, "eth1.10", IFNAMSIZ - 1);
setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, (void *)&if_opts, sizeof(if_opts);
ioctl(sock, SIOCGIFFLAGS, &if_opts);
if_opts.ifr_flags |= IFF_PROMISC;
ioctl(sock, SIOCSIFFLAGS, &if_opts);

setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE,
                  "eth1.10",
                  sizeof("eth1.10"));

Recv: size = recvfrom(sock, buf, BUF_SIZE, MSG_DONTWAIT, NULL, NULL);

0 + 7

tag

vlan

David

12/25/22, 5:57 AM

You have not given any info on the version of Ubuntu. How are you sending these packets what exact commands.

bobby

12/25/22, 5:50 PM

To find the version, I used the command uname -srm. Here is the dump:

bobby

12/25/22, 6:05 PM

To find the version, I used the command uname -srm. Here is the dump: Linux 4.19.0-xilinx-v2019.1 aarch64. Now for packet send: A socket is created using sock = socket(AF_PACKET, SOCK_RAW, htons(MY_ETHTYPE)); packet is sent with dmac 0xffff.ffff.ffff and smac is local interface mac. Packet is tagged with 0x8100000a or 0x81000014, ethertype as MY_ETHTYPE followed by payload. Packet is sent using call sendto(xmtSock, buf, bufSize, 0, (struct sockaddr *)sa_raw, sizeof(sa_raw)); sa_raw has sll_ifindex, sll_halen & sll_addr fields filed in.

David

12/26/22, 5:24 AM

There is no version info in that. A version would be like Ubuntu 18.04

bobby

12/26/22, 10:01 PM

Hi David, Which command I could use to find the version number?

David

12/27/22, 5:15 AM

Open your terminal either by using the Ctrl+Alt+T keyboard shortcut or by clicking on the terminal icon. Use the lsb_release -a command to display the Ubuntu version. Your Ubuntu version will be shown in the Description line. BTW a quick search on google could have given you this info.

bobby

12/28/22, 1:24 AM

lsb_release was not being supported. I found /etc/os-release after googling. Here is the dump: ID ="petalinux" Version="2019.1 (thud)". I guess it means it is not ubuntu. But still if you could point me to changes that might be needed to make the similar code to work on ubuntu, I will really appreciate. thanks

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: 2 sent pkts have tag for vlan 10 & 20, one should be received on socket created on eth1.10 and another on socket for eth1.20. But it doesn't happen

TH: 2 pkts ที่ส่งมีแท็กสำหรับ vlan 10 & 20 หนึ่งอันควรได้รับบนซ็อกเก็ตที่สร้างขึ้นบน eth1.10 และอีกอันบนซ็อกเก็ตสำหรับ eth1.20 แต่มันไม่เกิดขึ้น

RO: 2 pachete trimise au etichetă pentru vlan 10 și 20, unul ar trebui să fie primit pe socket-ul creat pe eth1.10 și altul pe socket pentru eth1.20. Dar nu se întâmplă

RU: 2 отправленных пакета имеют тег для vlan 10 и 20, один должен быть получен на сокете, созданном на eth1.10, а другой на сокете для eth1.20. Но этого не происходит

VI: 2 gói đã gửi có thẻ cho vlan 10 & 20, một gói sẽ được nhận trên ổ cắm được tạo trên eth1.10 và một gói khác trên ổ cắm cho eth1.20. Nhưng nó không xảy ra

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