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Code Issues Releases Wiki Activity

UDP PDU is now working.

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This commit is contained in:
Matias
2011-08-12 21:17:44 -03:00
parent 81bcdeb402
commit 398ba31111
8 changed files with 121 additions and 44 deletions
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36
src/tcp.cpp
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@@ -128,36 +128,11 @@ void Tins::TCP::add_option(Options tcp_option, uint8_t length, uint8_t *data) {
_total_options_size = (padding) ? _options_size - padding + 4 : _options_size;
}
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;
}
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, PDU *parent) {
void Tins::TCP::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *parent) {
assert(total_sz >= header_size());
uint8_t *tcp_start = buffer;
buffer += sizeof(tcphdr);
@@ -175,11 +150,10 @@ void Tins::TCP::write_serialization(uint8_t *buffer, uint32_t total_sz, PDU *par
memcpy(buffer, _payload, _payload_size);
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));
const IP *ip_packet = dynamic_cast<const IP*>(parent);
if(!_tcp.check && ip_packet) {
uint32_t checksum = PDU::pseudoheader_checksum(ip_packet->source_address(), ip_packet->dest_address(), header_size(), IPPROTO_TCP) +
PDU::do_checksum(tcp_start + sizeof(tcphdr), buffer) + PDU::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);