ETHER_HEADER_LENGTH
ETHER_HEADER_LENGTH + offsetof(struct ip, ip_p),
ETHER_HEADER_LENGTH + offsetof(struct ip6_hdr, ip6_nxt),
device->mtu = ETHER_MAX_FRAME_SIZE - ETHER_HEADER_LENGTH;
device->header_length = ETHER_HEADER_LENGTH;
if (buffer->size > device->frame_size || buffer->size < ETHER_HEADER_LENGTH)
if (mtu > device->frame_size - ETHER_HEADER_LENGTH
|| mtu <= ETHER_HEADER_LENGTH + 10)
if (mtu > device->frame_size - ETHER_HEADER_LENGTH - 8
|| mtu <= ETHER_HEADER_LENGTH + 8 + 10)
#define PPP_HEADER_LENGTH (8 + ETHER_HEADER_LENGTH)