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Change tcp_ip directory structure

This commit is contained in:
Matias Fontanini
2016-02-09 19:56:30 -08:00
parent 69fc5ff54b
commit 3b848060aa
10 changed files with 399 additions and 265 deletions

521
src/tcp_ip/stream.cpp Normal file
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/*
* Copyright (c) 2016, Matias Fontanini
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "tcp_ip/stream.h"
#if TINS_IS_CXX11
#include <limits>
#include <algorithm>
#include "memory.h"
#include "ip_address.h"
#include "ipv6_address.h"
#include "tcp.h"
#include "ip.h"
#include "ipv6.h"
#include "ethernetII.h"
#include "rawpdu.h"
#include "exceptions.h"
#include "memory_helpers.h"
using std::make_pair;
using std::bind;
using std::pair;
using std::runtime_error;
using std::numeric_limits;
using std::max;
using std::swap;
using Tins::Memory::OutputMemoryStream;
using Tins::Memory::InputMemoryStream;
namespace Tins {
namespace TCPIP {
// As defined by RFC 1982 - 2 ^ (SERIAL_BITS - 1)
static const uint32_t seq_number_diff = 2147483648U;
// Compares sequence numbers as defined by RFC 1982.
int seq_compare(uint32_t seq1, uint32_t seq2) {
if (seq1 == seq2) {
return 0;
}
if (seq1 < seq2) {
return (seq2 - seq1 < seq_number_diff) ? -1 : 1;
}
else {
return (seq1 - seq2 > seq_number_diff) ? -1 : 1;
}
}
// Flow
Flow::Flow(const IPv4Address& dest_address, uint16_t dest_port,
uint32_t sequence_number)
: seq_number_(sequence_number), dest_port_(dest_port), state_(UNKNOWN),
is_v6_(false), ignore_data_packets_(false) {
OutputMemoryStream output(dest_address_.data(), dest_address_.size());
output.write(dest_address);
}
Flow::Flow(const IPv6Address& dest_address, uint16_t dest_port,
uint32_t sequence_number)
: seq_number_(sequence_number), dest_port_(dest_port), state_(UNKNOWN),
is_v6_(true), ignore_data_packets_(false) {
OutputMemoryStream output(dest_address_.data(), dest_address_.size());
output.write(dest_address);
}
void Flow::data_callback(const data_available_callback_type& callback) {
on_data_callback_ = callback;
}
void Flow::out_of_order_callback(const out_of_order_callback_type& callback) {
on_out_of_order_callback_ = callback;
}
void Flow::process_packet(PDU& pdu) {
TCP* tcp = pdu.find_pdu<TCP>();
RawPDU* raw = pdu.find_pdu<RawPDU>();
// If we sent a packet with RST or FIN on, this flow is done
if (tcp) {
update_state(*tcp);
}
if (ignore_data_packets_) {
return;
}
if (!tcp || !raw) {
return;
}
const uint32_t chunk_end = tcp->seq() + raw->payload_size();
// If the end of the chunk ends after our current sequence number, process it.
if (seq_compare(chunk_end, seq_number_) >= 0) {
bool added_some = false;
uint32_t seq = tcp->seq();
// If we're going to buffer this and we have a buffering callback, execute it
if (seq > seq_number_ && on_out_of_order_callback_) {
on_out_of_order_callback_(*this, seq, raw->payload());
}
// If it starts before our sequence number, slice it
if (seq_compare(seq, seq_number_) < 0) {
const uint32_t diff = seq_number_ - seq;
raw->payload().erase(
raw->payload().begin(),
raw->payload().begin() + diff
);
seq = seq_number_;
}
// Store this payload
store_payload(seq, move(raw->payload()));
// Keep looping while the fragments seq is lower or equal to our seq
buffered_payload_type::iterator iter = buffered_payload_.find(seq_number_);
while (iter != buffered_payload_.end() && seq_compare(iter->first, seq_number_) <= 0) {
// Does this fragment start before our sequence number?
if (seq_compare(iter->first, seq_number_) < 0) {
uint32_t fragment_end = iter->first + iter->second.size();
int comparison = seq_compare(fragment_end, seq_number_);
// Does it end after our sequence number?
if (comparison > 0) {
// Then slice it
payload_type& payload = iter->second;
payload.erase(
payload.begin(),
payload.begin() + (seq_number_ - iter->first)
);
store_payload(seq_number_, move(iter->second));
iter = erase_iterator(iter);
}
else {
// Otherwise, we've seen this part of the payload. Erase it.
iter = erase_iterator(iter);
}
}
else {
// They're equal. Add this payload.
payload_.insert(
payload_.end(),
iter->second.begin(),
iter->second.end()
);
seq_number_ += iter->second.size();
iter = erase_iterator(iter);
added_some = true;
// If we don't have any other payload, we're done
if (buffered_payload_.empty()) {
break;
}
}
}
if (added_some) {
if (on_data_callback_) {
on_data_callback_(*this);
}
}
}
}
void Flow::store_payload(uint32_t seq, payload_type payload) {
buffered_payload_type::iterator iter = buffered_payload_.find(seq);
// New segment, store it
if (iter == buffered_payload_.end()) {
buffered_payload_.insert(make_pair(seq, move(payload)));
}
else if (iter->second.size() < payload.size()) {
// If we already have payload on this position but it's a shorter
// chunk than the new one, replace it
iter->second = move(payload);
}
}
Flow::buffered_payload_type::iterator Flow::erase_iterator(buffered_payload_type::iterator iter) {
buffered_payload_type::iterator output = iter;
++output;
buffered_payload_.erase(iter);
if (output == buffered_payload_.end()) {
output = buffered_payload_.begin();
}
return output;
}
void Flow::update_state(const TCP& tcp) {
if ((tcp.flags() & TCP::FIN) != 0) {
state_ = FIN_SENT;
}
else if ((tcp.flags() & TCP::RST) != 0) {
state_ = RST_SENT;
}
else if (state_ == SYN_SENT && (tcp.flags() & TCP::ACK) != 0) {
state_ = ESTABLISHED;
seq_number_++;
}
else if (state_ == UNKNOWN && (tcp.flags() & TCP::SYN) != 0) {
state_ = SYN_SENT;
seq_number_ = tcp.seq();
}
}
bool Flow::is_v6() const {
return is_v6_;
}
bool Flow::is_finished() const {
return state_ == FIN_SENT || state_ == RST_SENT;
}
bool Flow::packet_belongs(const PDU& packet) const {
if (is_v6()) {
const IPv6* ip = packet.find_pdu<IPv6>();
if (!ip || ip->dst_addr() != dst_addr_v6()) {
return false;
}
}
else {
const IP* ip = packet.find_pdu<IP>();
if (!ip || ip->dst_addr() != dst_addr_v4()) {
return false;
}
}
const TCP* tcp = packet.find_pdu<TCP>();
return tcp && tcp->dport() == dport();
}
IPv4Address Flow::dst_addr_v4() const {
InputMemoryStream stream(dest_address_.data(), dest_address_.size());
return stream.read<IPv4Address>();
}
IPv6Address Flow::dst_addr_v6() const {
InputMemoryStream stream(dest_address_.data(), dest_address_.size());
return stream.read<IPv6Address>();
}
uint16_t Flow::dport() const {
return dest_port_;
}
const Flow::payload_type& Flow::payload() const {
return payload_;
}
Flow::State Flow::state() const {
return state_;
}
uint32_t Flow::sequence_number() const {
return seq_number_;
}
const Flow::buffered_payload_type& Flow::buffered_payload() const {
return buffered_payload_;
}
Flow::buffered_payload_type& Flow::buffered_payload() {
return buffered_payload_;
}
Flow::payload_type& Flow::payload() {
return payload_;
}
void Flow::state(State new_state) {
state_ = new_state;
}
void Flow::ignore_data_packets() {
ignore_data_packets_ = true;
}
// Stream
Stream::Stream(const PDU& packet)
: client_flow_(extract_client_flow(packet)),
server_flow_(extract_server_flow(packet)), auto_cleanup_(true) {
const TCP& tcp = packet.rfind_pdu<TCP>();
// If it's a SYN, set the proper state
if (tcp.flags() == TCP::SYN) {
client_flow().state(Flow::SYN_SENT);
}
const EthernetII* eth = packet.find_pdu<EthernetII>();
if (eth) {
client_hw_addr_ = eth->src_addr();
server_hw_addr_ = eth->dst_addr();
}
}
void Stream::process_packet(PDU& packet) {
if (client_flow_.packet_belongs(packet)) {
client_flow_.process_packet(packet);
}
else if (server_flow_.packet_belongs(packet)) {
server_flow_.process_packet(packet);
}
if (is_finished() && on_stream_closed_) {
on_stream_closed_(*this);
}
}
Flow& Stream::client_flow() {
return client_flow_;
}
const Flow& Stream::client_flow() const {
return client_flow_;
}
Flow& Stream::server_flow() {
return server_flow_;
}
const Flow& Stream::server_flow() const {
return server_flow_;
}
void Stream::stream_closed_callback(const stream_callback_type& callback) {
on_stream_closed_ = callback;
}
void Stream::client_data_callback(const stream_callback_type& callback) {
on_client_data_callback_ = callback;
}
void Stream::server_data_callback(const stream_callback_type& callback) {
on_server_data_callback_ = callback;
}
void Stream::client_out_of_order_callback(const out_of_order_callback_type& callback) {
on_client_out_of_order_callback_ = callback;
}
void Stream::server_out_of_order_callback(const out_of_order_callback_type& callback) {
on_server_out_of_order_callback_ = callback;
}
void Stream::ignore_client_data() {
client_flow().ignore_data_packets();
}
void Stream::ignore_server_data() {
server_flow().ignore_data_packets();
}
bool Stream::is_finished() const {
const Flow::State client_state = client_flow_.state();
const Flow::State server_state = server_flow_.state();
// If either peer sent a RST then the stream is done
if (client_state == Flow::RST_SENT || server_state == Flow::RST_SENT) {
return true;
}
else {
// Otherwise, only finish if both sent a FIN
return client_state == Flow::FIN_SENT && server_state == Flow::FIN_SENT;
}
}
bool Stream::is_v6() const {
return server_flow().is_v6();
}
IPv4Address Stream::client_addr_v4() const {
return server_flow().dst_addr_v4();
}
IPv6Address Stream::client_addr_v6() const {
return server_flow().dst_addr_v6();
}
const Stream::hwaddress_type& Stream::client_hw_addr() const {
return client_hw_addr_;
}
const Stream::hwaddress_type& Stream::server_hw_addr() const {
return server_hw_addr_;
}
IPv4Address Stream::server_addr_v4() const {
return client_flow().dst_addr_v4();
}
IPv6Address Stream::server_addr_v6() const {
return client_flow().dst_addr_v6();
}
uint16_t Stream::client_port() const {
return server_flow().dport();
}
uint16_t Stream::server_port() const {
return client_flow().dport();
}
const Stream::payload_type& Stream::client_payload() const {
return client_flow().payload();
}
Stream::payload_type& Stream::client_payload() {
return client_flow().payload();
}
const Stream::payload_type& Stream::server_payload() const {
return server_flow().payload();
}
Stream::payload_type& Stream::server_payload() {
return server_flow().payload();
}
Flow Stream::extract_client_flow(const PDU& packet) {
const TCP* tcp = packet.find_pdu<TCP>();
if (!tcp) {
// TODO: define proper exception
throw runtime_error("No TCP");
}
if (const IP* ip = packet.find_pdu<IP>()) {
return Flow(ip->dst_addr(), tcp->dport(), tcp->seq());
}
else if (const IPv6* ip = packet.find_pdu<IPv6>()) {
return Flow(ip->dst_addr(), tcp->dport(), tcp->seq());
}
else {
// TODO: define proper exception
throw runtime_error("No valid layer 3");
}
}
Flow Stream::extract_server_flow(const PDU& packet) {
const TCP* tcp = packet.find_pdu<TCP>();
if (!tcp) {
// TODO: define proper exception
throw runtime_error("No TCP");
}
if (const IP* ip = packet.find_pdu<IP>()) {
return Flow(ip->src_addr(), tcp->sport(), tcp->ack_seq());
}
else if (const IPv6* ip = packet.find_pdu<IPv6>()) {
return Flow(ip->src_addr(), tcp->sport(), tcp->ack_seq());
}
else {
// TODO: define proper exception
throw runtime_error("No valid layer 3");
}
}
void Stream::setup_flows_callbacks() {
using namespace std::placeholders;
client_flow_.data_callback(bind(&Stream::on_client_flow_data, this, _1));
server_flow_.data_callback(bind(&Stream::on_server_flow_data, this, _1));
client_flow_.out_of_order_callback(bind(&Stream::on_client_out_of_order,
this, _1, _2, _3));
server_flow_.out_of_order_callback(bind(&Stream::on_server_out_of_order,
this, _1, _2, _3));
}
void Stream::auto_cleanup_payloads(bool value) {
auto_cleanup_ = value;
}
void Stream::on_client_flow_data(const Flow& /*flow*/) {
if (on_client_data_callback_) {
on_client_data_callback_(*this);
}
if (auto_cleanup_) {
client_payload().clear();
}
}
void Stream::on_server_flow_data(const Flow& /*flow*/) {
if (on_server_data_callback_) {
on_server_data_callback_(*this);
}
if (auto_cleanup_) {
server_payload().clear();
}
}
void Stream::on_client_out_of_order(const Flow& flow,
uint32_t seq,
const payload_type& payload) {
if (on_client_out_of_order_callback_) {
on_client_out_of_order_callback_(*this, seq, payload);
}
}
void Stream::on_server_out_of_order(const Flow& flow,
uint32_t seq,
const payload_type& payload) {
if (on_server_out_of_order_callback_) {
on_server_out_of_order_callback_(*this, seq, payload);
}
}
} // TCPIP
} // Tins
#endif // TINS_IS_CXX11