void ICMPv4::ping_reply(full_header* full_hdr, uint16_t size) {
auto packet_ptr = inet_.create_packet(size);
auto buf = packet_ptr->buffer();
icmp_header* hdr = &reinterpret_cast<full_header*>(buf)->icmp_hdr;
hdr->type = ICMP_ECHO_REPLY;
hdr->code = 0;
hdr->identifier = full_hdr->icmp_hdr.identifier;
hdr->sequence = full_hdr->icmp_hdr.sequence;
debug("<ICMP> Rest of header IN: 0x%lx OUT: 0x%lx\n",
full_hdr->icmp_hdr.rest, hdr->rest);
debug("<ICMP> Transmitting answer\n");
// Populate response IP header
auto ip4_pckt = static_unique_ptr_cast<PacketIP4>(std::move(packet_ptr));
ip4_pckt->init();
ip4_pckt->set_src(full_hdr->ip_hdr.daddr);
ip4_pckt->set_dst(full_hdr->ip_hdr.saddr);
ip4_pckt->set_protocol(IP4::IP4_ICMP);
ip4_pckt->set_ip_data_length(sizeof(icmp_header) + size - sizeof(full_header));
// Copy payload from old to new packet
uint8_t* payload = reinterpret_cast<uint8_t*>(hdr) + sizeof(icmp_header);
uint8_t* source = reinterpret_cast<uint8_t*>(&full_hdr->icmp_hdr) + sizeof(icmp_header);
memcpy(payload, source, size - sizeof(full_header));
hdr->checksum = 0;
hdr->checksum = net::checksum(reinterpret_cast<uint16_t*>(hdr),
size - sizeof(full_header) + sizeof(icmp_header));
network_layer_out_(std::move(ip4_pckt));
}
void UDP::transmit(UDP::Packet_ptr udp) {
debug2("<UDP> Transmitting %i bytes (seg=%i) from %s to %s:%i\n",
udp->length(), udp->ip4_segment_size(),
udp->src().str().c_str(),
udp->dst().str().c_str(), udp->dst_port());
assert(udp->length() >= sizeof(udp_header));
assert(udp->protocol() == IP4::IP4_UDP);
auto pckt = Packet::packet(udp);
network_layer_out_(pckt);
}
