mirror of
https://github.com/mfontanini/libtins
synced 2026-01-23 02:35:57 +01:00
69 lines
2.3 KiB
C++
69 lines
2.3 KiB
C++
/*
|
|
* libtins is a net packet wrapper library for crafting and
|
|
* interpreting sniffed packets.
|
|
*
|
|
* Copyright (C) 2011 Nasel
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#ifndef WIN32
|
|
#include <netinet/in.h>
|
|
#endif
|
|
#include <cassert>
|
|
#include <cstring>
|
|
#include "utils.h"
|
|
#include "udp.h"
|
|
#include "ip.h"
|
|
#include "rawpdu.h"
|
|
|
|
Tins::UDP::UDP(uint16_t sport, uint16_t dport) : PDU(IPPROTO_UDP) {
|
|
_udp.sport = sport;
|
|
_udp.dport = dport;
|
|
_udp.check = 0;
|
|
_udp.len = 0;
|
|
}
|
|
|
|
void Tins::UDP::payload(uint8_t *new_payload, uint32_t new_payload_size) {
|
|
inner_pdu(new RawPDU(new_payload, new_payload_size));
|
|
_udp.len = Utils::net_to_host_s(sizeof(udphdr) + new_payload_size);
|
|
}
|
|
|
|
void Tins::UDP::dport(uint16_t new_dport) {
|
|
_udp.dport = new_dport;
|
|
}
|
|
|
|
void Tins::UDP::sport(uint16_t new_sport) {
|
|
_udp.sport = new_sport;
|
|
}
|
|
|
|
uint32_t Tins::UDP::header_size() const {
|
|
return sizeof(udphdr);
|
|
}
|
|
|
|
void Tins::UDP::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *parent) {
|
|
assert(total_sz >= sizeof(udphdr));
|
|
const IP *ip_packet = dynamic_cast<const IP*>(parent);
|
|
if(!_udp.check && ip_packet) {
|
|
uint32_t checksum = PDU::pseudoheader_checksum(ip_packet->source_address(), ip_packet->dest_address(), size(), IPPROTO_UDP) +
|
|
PDU::do_checksum(buffer + sizeof(udphdr), buffer + total_sz) + PDU::do_checksum((uint8_t*)&_udp, ((uint8_t*)&_udp) + sizeof(udphdr));
|
|
while (checksum >> 16)
|
|
checksum = (checksum & 0xffff)+(checksum >> 16);
|
|
_udp.check = Utils::net_to_host_s(~checksum);
|
|
}
|
|
std::memcpy(buffer, &_udp, sizeof(udphdr));
|
|
}
|
|
|