3rd-party/libtins
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Code Issues Releases Wiki Activity

Solved conflicts.

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This commit is contained in:
Matias F
2011-08-12 20:24:51 -03:00
parent 35c1a6e65d 2cdf0f6b29
commit 81bcdeb402
7 changed files with 124 additions and 35 deletions
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42
src/tcp.cpp
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@@ -21,10 +21,12 @@
#include <cstring>
#include <cassert>
#include <iostream> //borrame
#ifndef WIN32
#include <netinet/in.h>
#endif
#include "tcp.h"
#include "ip.h"
#include "utils.h"
@@ -126,10 +128,28 @@ void Tins::TCP::add_option(Options tcp_option, uint8_t length, uint8_t *data) {
_total_options_size = (padding) ? _options_size - padding + 4 : _options_size;
}
uint16_t Tins::TCP::do_checksum(uint8_t *start, uint8_t *end) const {
unsigned checksum(0);
while(start < end)
checksum += *(start++);
uint32_t Tins::TCP::do_checksum(uint8_t *start, uint8_t *end) const {
uint32_t checksum(0);
uint16_t *ptr = (uint16_t*)start, *last = (uint16_t*)end, padding(0);
if(((end - start) & 1) == 1) {
last = (uint16_t*)end - 1;
padding = *(end - 1) << 8;
}
while(ptr < last)
checksum += Utils::net_to_host_s(*(ptr++));
return checksum + padding;
}
uint32_t Tins::TCP::pseudoheader_checksum(uint32_t source_ip, uint32_t dest_ip) const {
uint32_t checksum(0), len(header_size());
source_ip = Utils::net_to_host_l(source_ip);
dest_ip = Utils::net_to_host_l(dest_ip);
uint16_t *ptr = (uint16_t*)&source_ip;
checksum += *ptr + ptr[1];
ptr = (uint16_t*)&dest_ip;
checksum += *ptr + ptr[1];
checksum += IPPROTO_TCP + len;
return checksum;
}
@@ -137,7 +157,7 @@ uint32_t Tins::TCP::header_size() const {
return sizeof(tcphdr) + _payload_size + _total_options_size;
}
void Tins::TCP::write_serialization(uint8_t *buffer, uint32_t total_sz) {
void Tins::TCP::write_serialization(uint8_t *buffer, uint32_t total_sz, PDU *parent) {
assert(total_sz >= header_size());
uint8_t *tcp_start = buffer;
buffer += sizeof(tcphdr);
@@ -154,8 +174,16 @@ void Tins::TCP::write_serialization(uint8_t *buffer, uint32_t total_sz) {
}
memcpy(buffer, _payload, _payload_size);
if(!_tcp.check)
_tcp.check = Utils::net_to_host_s(do_checksum(tcp_start + sizeof(tcphdr), buffer));
buffer += _payload_size;
IP *ip_packet = dynamic_cast<IP*>(parent);
if(ip_packet) {
_tcp.check = 0;
uint32_t checksum = pseudoheader_checksum(ip_packet->source_address(), ip_packet->dest_address()) +
do_checksum(tcp_start + sizeof(tcphdr), buffer) + do_checksum((uint8_t*)&_tcp, ((uint8_t*)&_tcp) + sizeof(tcphdr));
while (checksum >> 16)
checksum = (checksum & 0xffff)+(checksum >> 16);
_tcp.check = Utils::net_to_host_s(~checksum);
}
memcpy(tcp_start, &_tcp, sizeof(tcphdr));
}