bool TCPStream::generic_process(uint32_t& my_seq,
uint32_t& /*other_seq*/,
payload_type& pload,
fragments_type& frags,
TCP* tcp) {
bool added_some(false);
if (tcp->get_flag(TCP::FIN) || tcp->get_flag(TCP::RST)) {
fin_sent_ = true;
}
RawPDU* raw = static_cast<RawPDU*>(tcp->release_inner_pdu());
if (raw) {
const uint32_t chunk_end = add_sequence_numbers(tcp->seq(), raw->payload_size());
// If the end of the chunk ends after our current sequence number, process it.
if (compare_seq_numbers(chunk_end, my_seq) >= 0) {
uint32_t seq = tcp->seq();
// If it starts before our sequence number, slice it
if (compare_seq_numbers(seq, my_seq) < 0) {
const uint32_t diff = subtract_sequence_numbers(my_seq, seq);
raw->payload().erase(
raw->payload().begin(),
raw->payload().begin() + diff
);
seq = my_seq;
}
safe_insert(frags, seq, raw);
fragments_type::iterator it = frags.find(my_seq);
// Keep looping while the fragments seq is lower or equal to our seq
while (it != frags.end() && compare_seq_numbers(it->first, my_seq) <= 0) {
// Does this fragment start before our sequence number?
if (compare_seq_numbers(it->first, my_seq) < 0) {
uint32_t fragment_end = add_sequence_numbers(it->first, it->second->payload_size());
int comparison = compare_seq_numbers(fragment_end, my_seq);
// Does it end after our sequence number?
if (comparison > 0) {
// Then slice it
RawPDU::payload_type& payload = it->second->payload();
payload.erase(
payload.begin(),
payload.begin() + subtract_sequence_numbers(my_seq, it->first)
);
safe_insert(frags, my_seq, it->second);
it = erase_iterator(it, frags);
}
else {
// Otherwise, we've seen this part of the payload. Erase it.
delete it->second;
it = erase_iterator(it, frags);
}
}
else {
// They're equal. Add this payload.
pload.insert(
pload.end(),
it->second->payload().begin(),
it->second->payload().end()
);
my_seq += it->second->payload_size();
delete it->second;
it = erase_iterator(it, frags);
added_some = true;
if (frags.empty()) {
break;
}
}
}
}
else {
delete raw;
}
}
return added_some;
}
