Re-structuring on new model

This commit is contained in:
Domingo Dirutigliano
2025-02-14 01:04:29 +01:00
parent ec3bd84aaf
commit 63e7f73139
12 changed files with 366 additions and 116 deletions

View File

@@ -1,5 +1,5 @@
#ifndef PROXY_TUNNEL_CPP
#define PROXY_TUNNEL_CPP
#ifndef PROXY_TUNNEL_CLASS_CPP
#define PROXY_TUNNEL_CLASS_CPP
#include <linux/netfilter/nfnetlink_queue.h>
#include <libnetfilter_queue/libnetfilter_queue.h>
@@ -12,88 +12,157 @@
#include <linux/netfilter/nfnetlink.h>
#include <linux/types.h>
#include <stdexcept>
#include <thread>
#include <hs.h>
#include <syncstream>
#include <iostream>
#include "../classes/netfilter.cpp"
#include <functional>
#include "stream_ctx.cpp"
#include "settings.cpp"
using Tins::TCPIP::Stream;
using Tins::TCPIP::StreamFollower;
using namespace std;
typedef Tins::TCPIP::StreamIdentifier stream_id;
class SocketTunnelQueue: public NfQueueExecutor {
class PyProxyQueue: public NfQueueExecutor {
public:
StreamFollower follower;
stream_ctx sctx;
void before_loop() override {
follower.new_stream_callback(bind(on_new_stream, placeholders::_1));
follower.stream_termination_callback(bind(on_stream_close, placeholders::_1));
sctx.follower.new_stream_callback(bind(on_new_stream, placeholders::_1, &sctx));
sctx.follower.stream_termination_callback(bind(on_stream_close, placeholders::_1, &sctx));
}
void * callback_data_fetch() override{
return nullptr;
return &sctx;
}
static bool filter_action(){
static bool filter_action(packet_info& info){
shared_ptr<PyCodeConfig> conf = config;
auto stream_search = info.sctx->streams_ctx.find(info.sid);
pyfilter_ctx stream_match;
if (stream_search == info.sctx->streams_ctx.end()){
// TODO: New pyfilter_ctx
}else{
stream_match = stream_search->second;
}
bool has_matched = false;
//TODO exec filtering action
if (has_matched){
// Say to firegex what filter has matched
//osyncstream(cout) << "BLOCKED " << rules_vector[match_res.matched] << endl;
return false;
}
return true;
}
//If the stream has already been matched, drop all data, and try to close the connection
static void keep_fin_packet(stream_ctx* sctx){
sctx->match_info.matching_has_been_called = true;
sctx->match_info.already_closed = true;
}
static void on_data_recv(Stream& stream, string data, bool is_input) {
bool result = filter_action();
static void on_data_recv(Stream& stream, stream_ctx* sctx, string data) {
sctx->match_info.matching_has_been_called = true;
sctx->match_info.already_closed = false;
bool result = filter_action(*sctx->match_info.pkt_info);
if (!result){
stream.ignore_client_data();
stream.ignore_server_data();
sctx->clean_stream_by_id(sctx->match_info.pkt_info->sid);
stream.client_data_callback(bind(keep_fin_packet, sctx));
stream.server_data_callback(bind(keep_fin_packet, sctx));
}
sctx->match_info.result = result;
}
//Input data filtering
static void on_client_data(Stream& stream) {
on_data_recv(stream, string(stream.client_payload().begin(), stream.client_payload().end()), true);
static void on_client_data(Stream& stream, stream_ctx* sctx) {
sctx->match_info.pkt_info->is_input = true;
on_data_recv(stream, sctx, string(stream.client_payload().begin(), stream.client_payload().end()));
}
//Server data filtering
static void on_server_data(Stream& stream) {
on_data_recv(stream, string(stream.server_payload().begin(), stream.server_payload().end()), false);
static void on_server_data(Stream& stream, stream_ctx* sctx) {
sctx->match_info.pkt_info->is_input = false;
on_data_recv(stream, sctx, string(stream.server_payload().begin(), stream.server_payload().end()));
}
// A stream was terminated. The second argument is the reason why it was terminated
static void on_stream_close(Stream& stream) {
static void on_stream_close(Stream& stream, stream_ctx* sctx) {
stream_id stream_id = stream_id::make_identifier(stream);
sctx->clean_stream_by_id(stream_id);
}
static void on_new_stream(Stream& stream) {
static void on_new_stream(Stream& stream, stream_ctx* sctx) {
stream.auto_cleanup_payloads(true);
if (stream.is_partial_stream()) {
return;
//TODO take a decision about this...
stream.enable_recovery_mode(10 * 1024);
}
stream.client_data_callback(bind(on_client_data, placeholders::_1));
stream.server_data_callback(bind(on_server_data, placeholders::_1));
stream.stream_closed_callback(bind(on_stream_close, placeholders::_1));
stream.client_data_callback(bind(on_client_data, placeholders::_1, sctx));
stream.server_data_callback(bind(on_server_data, placeholders::_1, sctx));
stream.stream_closed_callback(bind(on_stream_close, placeholders::_1, sctx));
}
template<typename T>
static void build_verdict(T packet, uint8_t *payload, uint16_t plen, nlmsghdr *nlh_verdict, nfqnl_msg_packet_hdr *ph){
sctx->tcp_match_util.matching_has_been_called = false;
static void build_verdict(T packet, uint8_t *payload, uint16_t plen, nlmsghdr *nlh_verdict, nfqnl_msg_packet_hdr *ph, stream_ctx* sctx, bool is_ipv6){
Tins::TCP* tcp = packet.template find_pdu<Tins::TCP>();
if (!tcp){
throw invalid_argument("Only TCP and UDP are supported");
}
Tins::PDU* application_layer = tcp->inner_pdu();
u_int16_t payload_size = 0;
if (application_layer != nullptr){
payload_size = application_layer->size();
}
packet_info pktinfo{
payload: string(payload+plen - payload_size, payload+plen),
sid: stream_id::make_identifier(packet),
is_ipv6: is_ipv6,
sctx: sctx,
packet_pdu: &packet,
tcp: tcp,
};
sctx->match_info.matching_has_been_called = false;
sctx->match_info.pkt_info = &pktinfo;
sctx->follower.process_packet(packet);
if (sctx->tcp_match_util.matching_has_been_called && !sctx->tcp_match_util.result){
Tins::PDU* data_layer = tcp->release_inner_pdu();
if (data_layer != nullptr){
delete data_layer;
// Do an action only is an ordered packet has been received
if (sctx->match_info.matching_has_been_called){
bool empty_payload = pktinfo.payload.empty();
//In this 2 cases we have to remove all data about the stream
if (!sctx->match_info.result || sctx->match_info.already_closed){
#ifdef DEBUG
cerr << "[DEBUG] [NetfilterQueue.build_verdict] Stream matched, removing all data about it" << endl;
#endif
sctx->clean_stream_by_id(pktinfo.sid);
//If the packet has data, we have to remove it
if (!empty_payload){
Tins::PDU* data_layer = tcp->release_inner_pdu();
if (data_layer != nullptr){
delete data_layer;
}
}
//For the first matched data or only for data packets, we set FIN bit
//This only for client packets, because this will trigger server to close the connection
//Packets will be filtered anyway also if client don't send packets
if ((!sctx->match_info.result || !empty_payload) && is_input){
tcp->set_flag(Tins::TCP::FIN,1);
tcp->set_flag(Tins::TCP::ACK,1);
tcp->set_flag(Tins::TCP::SYN,0);
}
//Send the edited packet to the kernel
nfq_nlmsg_verdict_put_pkt(nlh_verdict, packet.serialize().data(), packet.size());
}
tcp->set_flag(Tins::TCP::FIN,1);
tcp->set_flag(Tins::TCP::ACK,1);
tcp->set_flag(Tins::TCP::SYN,0);
nfq_nlmsg_verdict_put_pkt(nlh_verdict, packet.serialize().data(), packet.size());
}
nfq_nlmsg_verdict_put(nlh_verdict, ntohl(ph->packet_id), NF_ACCEPT );
}
static int queue_cb(const nlmsghdr *nlh, const mnl_socket* nl, void *data_ptr) {
stream_ctx* sctx = (stream_ctx*)data_ptr;
//Extract attributes from the nlmsghdr
nlattr *attr[NFQA_MAX+1] = {};
@@ -116,23 +185,25 @@ class SocketTunnelQueue: public NfQueueExecutor {
struct nlmsghdr *nlh_verdict;
nlh_verdict = nfq_nlmsg_put(buf, NFQNL_MSG_VERDICT, ntohs(nfg->res_id));
// Check IP protocol version
if ( (payload[0] & 0xf0) == 0x40 ){
build_verdict(Tins::IP(payload, plen), payload, plen, nlh_verdict, ph);
build_verdict(Tins::IP(payload, plen), payload, plen, nlh_verdict, ph, sctx, false);
}else{
build_verdict(Tins::IPv6(payload, plen), payload, plen, nlh_verdict, ph);
build_verdict(Tins::IPv6(payload, plen), payload, plen, nlh_verdict, ph, sctx, true);
}
if (mnl_socket_sendto(nl, nlh_verdict, nlh_verdict->nlmsg_len) < 0) {
throw runtime_error( "mnl_socket_send" );
}
return MNL_CB_OK;
}
SocketTunnelQueue(int queue) : NfQueueExecutor(queue, &queue_cb) {}
PyProxyQueue(int queue) : NfQueueExecutor(queue, &queue_cb) {}
~PyProxyQueue() {
sctx.clean();
}
};
#endif // PROXY_TUNNEL_CPP
#endif // PROXY_TUNNEL_CLASS_CPP