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Why APP or ICMPv6 packets are not processed by Linux TAP

I open a TAP device using

p->fd = open("/dev/net/tun", O_RDWR);

// skipping error handling code

ifr.ifr_flags = IFF_TAP | IFF_ONE_QUEUE | IFF_NO_PI;
strncpy(ifr.ifr_name, p->name, IFNAMSIZ-1);
result = ioctl(p->fd, TUNSETIFF, &ifr);

// skipping error handling and setting ipv4 address & netmask code

ifr.ifr_flags = (IFF_UP | IFF_RUNNING);
result = ioctl(dummySock, SIOCSIFFLAGS, &ifr);

The problem I ran into is when an application (like mozilla) wants to send a packet through a tap device, it needs to get the dst mac address. Thus, the kernel sends an ARP request. The application I am writing redirects an arp request (via a raw socket on a physical device) and receives an arp response. This arp response is sent back to the crane device, but the kernel refuses to accept it. If I add the arp entry manually, the arp request will not be created, and there is a two-way ip exchange (mozilla glad).

Wireshark . ICMPv6 ( ). , , . ​​ ARP/ICMP.

: ​​ arp reply/ICMPv6? ioctl, ?

Edit:

( tshark) "ethgress" ,

  9  16.548328    fc00:1::2 -> ff02::1:ff00:1 ICMPv6 86 Neighbor Solicitation
 10  17.243247  fc00:1::100 -> fc00:1::2    ICMPv6 86 Neighbor Advertisement
 11  17.548652    fc00:1::2 -> ff02::1:ff00:1 ICMPv6 86 Neighbor Solicitation
 12  17.668736  fc00:1::100 -> fc00:1::2    ICMPv6 86 Neighbor Advertisement

ifconfig "ethgress"

ethgress  Link encap:Ethernet  HWaddr 00:01:02:03:04:05
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:83 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:10000
          RX bytes:0 (0.0 b)  TX bytes:7062 (6.8 KiB)

, ​​ ICMPv6 . tx .

"ethgress" IPv6 fc00: 1:: 2, fc00: 1:: 1. fc00: 1:: 1 , fc00: 1:100, ( ip fc00: 1:: 1 ) mac. Tcpdump , wirehark/tshark . Rx arp. ARP-.

2:

. , . . . , , . TAP. IP-. TAP IPv4, IPv6. , mozilla, . ​​ ARP-/ . . ARP ARP, TAP. arp tcpdump, ​​ arp. MAC- TAP .

.

cat /proc/sys/net/ipv4/conf/all/log_martians
0
cat /proc/sys/net/ipv4/conf/all/rp_filter
1
cat /proc/sys/net/ipv4/conf/all/arp_filter
0
+5
1

.

( TUN TAP https://security.stackexchange.com/questions/46442/openvpn-tap-vs-tun-mode)

TAP, ARP, .. Ethernet. ARP ICMPv6 - HW dst src. RP , , , .

TUN: ARP .., "" IP-.

0

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