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packet_handler.cpp
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packet_handler.cpp
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/*****************************************************************************
*
* GARGOYLE_PSCAND: Gargoyle - Protection for Linux
*
* packet handling code
*
* Copyright (c) 2016 - 2017, Bayshore Networks, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that
* the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
* following disclaimer.
*
* 2. 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.
*
* 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* 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 HOLDER 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 <iostream>
#include <algorithm>
#include <cstdlib>
#include <sstream>
#include <string>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <syslog.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <linux/netfilter.h>
#include <linux/tcp.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <sys/socket.h>
#include "iptables_wrapper_api.h"
#include "sqlite_wrapper_api.h"
#include "packet_handler.h"
#include "gargoyle_config_vals.h"
#include "ip_addr_controller.h"
#define MIN3(a, b, c) ((a) < (b) ? ((a) < (c) ? (a) : (c)) : ((b) < (c) ? (b) : (c)))
int FLAGS_LIST[] = {128, 64, 32, 16, 8, 4, 2, 1};
/*
* when ADD_RULES_KNOWN_SCAN_AGGRESSIVE is true
* automatic blocks will take place when known
* techniques (NULL, FIN, XMAS, etc) are
* detected
*/
bool ADD_RULES_KNOWN_SCAN_AGGRESSIVE = true;
bool SYSLOG_ALL_DETECTIONS = true;
bool DEBUG = true;
int BASE_TIME;
//int PROCESS_TIME_CHECK = 120;
int PROCESS_TIME_CHECK = 60;
size_t PH_SINGLE_IP_SCAN_THRESHOLD = 6;
size_t PH_SINGLE_PORT_SCAN_THRESHOLD = 5;
size_t PROCESSING_LIMIT = 200;
/////////////////////////////////////////////////////////////////////////////////
std::vector<int> calculate_flags(int dec) {
//std::cout << "INCMING FLAGS " << dec << std::endl;
std::vector<int> final;
int n;
for (n = 0; n < 8; ++n) {
if (dec >= FLAGS_LIST[n]) {
dec = dec - FLAGS_LIST[n];
final.push_back(FLAGS_LIST[n]);
}
}
return final;
}
static uint16_t checksum(const uint16_t* buf, unsigned int nbytes) {
uint32_t sum = 0;
for (; nbytes > 1; nbytes -= 2)
{
sum += *buf++;
}
if (nbytes == 1)
{
sum += *(unsigned char*) buf;
}
sum = (sum >> 16) + (sum & 0xFFFF);
sum += (sum >> 16);
return ~sum;
}
void *bayshoresubstring(size_t start, size_t stop, const char *src, char *dst, size_t size) {
if (!dst) return NULL;
int count = stop - start;
if ( count >= --size ) {
count = size;
}
sprintf(dst, "%.*s", count, src + start);
return dst;
}
int levenshtein(const char *s1, const char *s2) {
unsigned int s1len, s2len, x, y, lastdiag, olddiag;
s1len = strlen(s1);
s2len = strlen(s2);
unsigned int column[s1len+1];
for (y = 1; y <= s1len; y++)
column[y] = y;
for (x = 1; x <= s2len; x++) {
column[0] = x;
for (y = 1, lastdiag = x-1; y <= s1len; y++) {
olddiag = column[y];
column[y] = MIN3(column[y] + 1, column[y-1] + 1, lastdiag + (s1[y-1] == s2[x-1] ? 0 : 1));
lastdiag = olddiag;
}
}
return(column[s1len]);
}
/////////////////////////////////////////////////////////////////////////////////
GargoylePscandHandler::GargoylePscandHandler() {
BASE_TIME = (int) time(NULL);
ENFORCE = true;
PH_SINGLE_IP_SCAN_THRESHOLD = 6;
PH_SINGLE_PORT_SCAN_THRESHOLD = 5;
IGNORE_WHITE_LISTED_IP_ADDRS = false;
EPHEMERAL_LOW = 1024;
EPHEMERAL_HIGH = 65535;
IPTABLES_SUPPORTS_XLOCK = 0;
gargoyle_whitelist_shm = SharedIpConfig::Create(GARGOYLE_WHITELIST_SHM_NAME, GARGOYLE_WHITELIST_SHM_SZ);
gargoyle_blacklist_shm = SharedIpConfig::Create(GARGOYLE_BLACKLIST_SHM_NAME, GARGOYLE_BLACKLIST_SHM_SZ);
}
GargoylePscandHandler::~GargoylePscandHandler() {
if(gargoyle_whitelist_shm) {
delete gargoyle_whitelist_shm;
//gargoyle_whitelist_shm;
}
if(gargoyle_blacklist_shm) {
delete gargoyle_blacklist_shm;
//gargoyle_blacklist_shm;
}
}
int GargoylePscandHandler::packet_handle(struct nflog_g_handle *gh, struct nfgenmsg *nfmsg, struct nflog_data *nfa, void *ldata)
{
GargoylePscandHandler* _this = (GargoylePscandHandler *)ldata;
if (_this) {
int id = 0;
/*
struct nfulnl_msg_packet_hdr* ph = nflog_get_msg_packet_hdr(nfa);
if (ph)
{
//id = ntohl(ph->packet_id);
//printf("hw_protocol=0x%04x hook=%u id=%u ", ntohs(ph->hw_protocol), ph->hook, id);
}
*/
/*
struct nfulnl_msg_packet_hw* hwph = nflog_get_packet_hw(nfa);
if (hwph)
{
int i, hlen = ntohs(hwph->hw_addrlen);
printf("hw_src_addr=");
for (i = 0; i < hlen-1; i++)
printf("%02x:", hwph->hw_addr[i]);
printf("%02x ", hwph->hw_addr[hlen-1]);
}
*/
/*
u_int32_t mark = nflog_get_nfmark(nfa);
if (mark)
printf("mark=%u ", mark);
*/
/*
u_int32_t ifi = nflog_get_indev(nfa);
if (ifi)
printf("indev=%u ", ifi);
ifi = nflog_get_outdev(nfa);
if (ifi)
printf("outdev=%u ", ifi);
ifi = nflog_get_physindev(nfa);
if (ifi)
printf("physindev=%u ", ifi);
ifi = nflog_get_physoutdev(nfa);
if (ifi)
printf("physoutdev=%u ", ifi);
*/
char *data;
int ret = nflog_get_payload(nfa, &data);
if (ret < 0)
return 0;
if (ret >= sizeof(struct iphdr))
{
struct iphdr* ip = (struct iphdr*)(data);
// TCP
if (ip->protocol == IPPROTO_TCP) {
u_int16_t flags = ntohs(ip->frag_off);
struct tcphdr *tcp_info;
unsigned short dst_port;
unsigned short src_port;
unsigned short seq_num;
unsigned short ack_num;
tcp_info = (struct tcphdr*)(data + sizeof(*ip));
dst_port = ntohs(tcp_info->dest);
src_port = ntohs(tcp_info->source);
seq_num = ntohs(tcp_info->seq);
ack_num = ntohs(tcp_info->ack_seq);
/*
printf("\n ip { version=%d, ihl=%d, tos=%d, len=%d, id=%d, flags=%d frag_off=%d, ttl=%d, protocol=%d, check=%d } ",
ip->version, ip->ihl, ip->tos, ntohs(ip->tot_len), ip->id, flags >> 13, flags & 0x1FFF, ip->ttl, ip->protocol, ntohs(ip->check)
);
*/
// we don't ignore this port
if (!_this->ignore_this_port(dst_port)) {
/*
* in_addr - a statically allocated buffer, which subsequent calls overwrite
* so it can't be used twice in a function, have to write out results and
* do again
*/
struct in_addr src_addr = {ip->saddr};
std::string s_src(inet_ntoa(src_addr));
struct in_addr dst_addr = {ip->daddr};
std::string s_dst(inet_ntoa(dst_addr));
// we dont ignore this ip addr
if (!_this->is_white_listed_ip_addr(s_src)) {
/////////////////////////////////////////////////////////////////
/*
* if there is a hit that is on the list
* of "hot ports" then this warrants an
* immediate block action as this means
* the user wants no activity on the
* specified port
*/
if (_this->is_in_hot_ports(dst_port)) {
/*
* We will not query iptables here as that overhead
* is unacceptable, the analysis process should
* catch and cleanup any dupes in iptables if that
* situation arises
*/
// get ix for ip_addr
int added_host_ix = add_host(s_src.c_str(), _this->DB_LOCATION.c_str());
if (added_host_ix == -1) {
// get existing index
added_host_ix = get_host_ix(s_src.c_str(), _this->DB_LOCATION.c_str());
}
//std:cout << added_host_ix << std::endl;
if (added_host_ix > 0) {
_this->add_block_rule(s_src, 9);
_this->add_to_scanned_ports_dict(s_src.c_str(), dst_port);
}
return 0;
}
/////////////////////////////////////////////////////////////////
/*
printf("\n { src_ip=%s, dst_ip=%s, src_port=%d, dst_port=%d, seq_num=%d, ack_num=%d }\n",
s_src.c_str(),
s_dst.c_str(),
src_port,
dst_port,
seq_num,
ack_num
);
*/
/*
std::cout << "FLAGS: - " << flags << std::endl;
//std::vector<int> tcp_flags = calculate_flags(flags >> 13);
std::cout << "URG: " << tcp_info->urg << std::endl;
std::cout << "ACK: " << tcp_info->ack << std::endl;
std::cout << "PSH: " << tcp_info->psh << std::endl;
std::cout << "RST: " << tcp_info->rst << std::endl;
std::cout << "SYN: " << tcp_info->syn << std::endl;
std::cout << "FIN: " << tcp_info->fin << std::endl;
*/
/*
* U A P R S F
* 32 16 8 4 2 1
*/
std::vector<int> tcp_flags;
if (tcp_info->urg)
tcp_flags.push_back(32);
if (tcp_info->ack)
tcp_flags.push_back(16);
if (tcp_info->psh)
tcp_flags.push_back(8);
if (tcp_info->rst)
tcp_flags.push_back(4);
if (tcp_info->syn)
tcp_flags.push_back(2);
if (tcp_info->fin)
tcp_flags.push_back(1);
/*
std::cout << "FLAGS: - " << tcp_flags.size() << std::endl;
for (std::vector<int>::const_iterator i = tcp_flags.begin(); i != tcp_flags.end(); ++i) {
std::cout << *i << " ";
}
std::cout << std::endl;
*/
if (s_src.size() > 0 && src_port > 0 && s_dst.size() > 0 && dst_port > 0) {
std::ostringstream testdata_tmp;
testdata_tmp << s_src << ":" << src_port << "->" << s_dst << ":" << dst_port;
std::string testdata = testdata_tmp.str();
/*
std::cout << "SRC: " << s_src << ", LEN: " << s_src.size() << " - " << ip->saddr << std::endl;
std::cout << "SRCPORT: " << src_port << std::endl;
std::cout << "DST: " << s_dst << ", LEN: " << s_dst.size() << " - " << ip->daddr << std::endl;
std::cout << "DSTPORT: " << dst_port << std::endl;
std::cout << "SEQ: " << seq_num << std::endl;
std::cout << "ACK: " << ack_num << std::endl;
std::cout << testdata << std::endl;
std::cout << "FLAG LEN: " << tcp_flags.size() << std::endl;
if (tcp_flags.size() > 0) {
std::cout << "FLAGS: " << std::endl;
for (std::vector<int>::const_iterator i = tcp_flags.begin(); i != tcp_flags.end(); ++i) {
std::cout << *i << " ";
}
}
std::cout << std::endl << std::endl;
*/
bool is_in = _this->THREE_WAY_HANDSHAKE.find(testdata) != _this->THREE_WAY_HANDSHAKE.end();
if (!is_in)
_this->three_way_check(s_src,src_port,s_dst,dst_port,seq_num,ack_num,tcp_flags);
_this->main_port_scan_check(s_src,src_port,s_dst,dst_port,seq_num,ack_num,tcp_flags);
}
}
}
} // end of TCP handling
// UDP
// TODO
///////////////////////////////////////////////////////////////////////////////
/*
* process to run at certain intervals (see PROCESS_TIME_CHECK)
* this is what flushes data from memory and blocks stuff
* if appropriate
*/
if (((int)time(NULL) - BASE_TIME) >= PROCESS_TIME_CHECK) {
// are there any new white list entries in the DB?
_this->process_ignore_ip_list();
_this->process_blacklist_ip_list();
_this->add_block_rules();
BASE_TIME = (int)time(NULL);
}
///////////////////////////////////////////////////////////////////////////////
}
}
return 0;
}
void GargoylePscandHandler::three_way_check (
std::string src_ip,
int src_port,
std::string dst_ip,
int dst_port,
int seq_num,
int ack_num,
std::vector<int> tcp_flags) {
/*
std::cout << "TCP_FLAGS: " << tcp_flags.size() << std::endl;
for (std::vector<int>::const_iterator i = tcp_flags.begin(); i != tcp_flags.end(); ++i) {
std::cout << *i << " ";
}
*/
if (tcp_flags.size() == 1 && tcp_flags[0] == 2) { // flags = SYN - len flags = 1
if(seq_num > 0 and ack_num == 0) {
std::ostringstream str_tmp;
str_tmp << seq_num << "_" << ack_num << "_" << src_ip << ":" << src_port << "->" << dst_ip << ":" << dst_port;
WAITING.insert(str_tmp.str());
}
} else if ((tcp_flags.size() == 2) &&
(std::find(tcp_flags.begin(), tcp_flags.end(), 2) != tcp_flags.end()) &&
(std::find(tcp_flags.begin(), tcp_flags.end(), 16) != tcp_flags.end())) { // flags = SYN,ACK - len flags = 2
for(twh_it = WAITING.begin(); twh_it != WAITING.end(); twh_it++) {
std::size_t pos = (*twh_it).find("_");
int seq_old = atoi(((*twh_it).substr(0, pos)).c_str());
if (ack_num == (seq_old + 1)) {
WAITING.erase(*twh_it);
std::ostringstream str_tmp;
str_tmp << seq_num << "_" << ack_num << "_" << src_ip << ":" << src_port << "->" << dst_ip << ":" << dst_port;
WAITING.insert(str_tmp.str());
break;
}
}
} else if (tcp_flags.size() == 1 && tcp_flags[0] == 16) { // flags = ACK - len flags = 1
for(twh_it = WAITING.begin(); twh_it != WAITING.end(); twh_it++) {
std::size_t pos = (*twh_it).find("_");
int seq_old = atoi(((*twh_it).substr(0, pos)).c_str());
std::size_t pos2_inc = pos + 1;
std::size_t pos2 = (*twh_it).find("_", pos2_inc);
int ack_old = atoi(((*twh_it).substr(pos2_inc, pos2 - pos2_inc)).c_str());
if ((ack_num == (seq_old + 1)) && (seq_num == ack_old)) {
WAITING.erase(*twh_it);
std::ostringstream str_tmp;
str_tmp << src_ip << ":" << src_port << "->" << dst_ip << ":" << dst_port;
THREE_WAY_HANDSHAKE.insert(str_tmp.str());
break;
}
}
}
}
bool GargoylePscandHandler::is_in_waiting(std::string s) {
//if(std::find(WAITING.begin(), WAITING.end(), s) != WAITING.end())
if (WAITING.count(s) != 0)
return true;
return false;
}
bool GargoylePscandHandler::is_in_scanned_ports_cnt_dict(std::string s) {
if(SCANNED_PORTS_CNT_DICT.find(s) != SCANNED_PORTS_CNT_DICT.end())
return true;
return false;
}
bool GargoylePscandHandler::is_in_black_listed_hosts(std::string s) {
if (BLACK_LISTED_HOSTS.count(s) != 0)
return true;
return false;
}
bool GargoylePscandHandler::is_in_three_way_handshake(std::string s) {
if (THREE_WAY_HANDSHAKE.count(s) != 0)
return true;
return false;
}
bool GargoylePscandHandler::is_white_listed_ip_addr(std::string s) {
bool result;
gargoyle_whitelist_shm->Contains(s, &result);
if (result)
return true;
return false;
}
bool GargoylePscandHandler::is_in_ports_entries(int s) {
ports_iter = std::find(IGNORE_PORTS.begin(), IGNORE_PORTS.end(), s);
if (ports_iter != IGNORE_PORTS.end())
return true;
return false;
}
void GargoylePscandHandler::add_to_white_listed_entries(std::string s) {
gargoyle_whitelist_shm->Add(s);
}
void GargoylePscandHandler::add_to_ports_entries(int s) {
if (!is_in_ports_entries(s))
IGNORE_PORTS.push_back(s);
}
void GargoylePscandHandler::main_port_scan_check(
std::string src_ip,
int src_port,
std::string dst_ip,
int dst_port,
int seq_num,
int ack_num,
std::vector<int> tcp_flags) {
/*
std::cout << "IP: " << src_ip << std::endl;
std::cout << "SZ: " << tcp_flags.size() << std::endl;
std::cout << "DST PORT: " << dst_port << std::endl << std::endl;
*/
clear_three_way_check_dat();
three_way_check_dat << src_ip << ":" << src_port << "->" << dst_ip << ":" << dst_port;
//three_way_check_dat = "{}:{}->{}:{}".format(src_ip, str(src_port), dst_ip, str(dst_port))
clear_reverse_three_way_check_dat();
reverse_three_way_check_dat << dst_ip << ":" << dst_port << "->" << src_ip << ":" << src_port;
//reverse_three_way_check_dat = "{}:{}->{}:{}".format(dst_ip, str(dst_port), src_ip, str(src_port))
clear_src_ip_dst_ip_dat();
src_ip_dst_ip_dat << src_ip << "->" << dst_ip;
//src_ip_dst_ip_dat = "{}->{}".format(src_ip, dst_ip)
clear_reverse_src_ip_dst_ip_dat();
reverse_src_ip_dst_ip_dat << dst_ip << "->" << src_ip;
//reverse_src_ip_dst_ip_dat = dst_ip + "->" + src_ip
size_t tcp_flags_sz = tcp_flags.size();
if (tcp_flags_sz == 0) {
int null_scan_ret = null_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
//std::cout << "null_scan_ret: " << null_scan_ret << std::endl;
if (null_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "NULL port scan detected");
return;
}
} else if (tcp_flags_sz == 1) {
int fin_scan_ret = fin_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
//std::cout << "fin_scan_ret: " << fin_scan_ret << std::endl;
if (fin_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "FIN port scan detected");
return;
}
} else if (tcp_flags_sz == 3) {
int xmas_scan_ret = xmas_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
if (xmas_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "XMAS port scan detected");
return;
}
}
/*
if (tcp_flags.size() == 3) {
int xmas_scan_ret = xmas_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
if (xmas_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "XMAS port scan detected");
return;
}
}
*/
/*
//int fin_scan_ret;
//if (xmas_scan_ret == 1) {
// fin_scan_ret = fin_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
if (tcp_flags.size() == 1) {
int fin_scan_ret = fin_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
//std::cout << "fin_scan_ret: " << fin_scan_ret << std::endl;
if (fin_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "FIN port scan detected");
return;
}
}
*/
/*
//int null_scan_ret;
//if (fin_scan_ret == 1) {
// null_scan_ret = null_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
if (tcp_flags.size() == 0) {
int null_scan_ret = null_scan(src_ip,src_port,dst_ip,dst_port,seq_num,ack_num,tcp_flags);
//std::cout << "null_scan_ret: " << null_scan_ret << std::endl;
if (null_scan_ret == 0) {
syslog(LOG_INFO | LOG_LOCAL6, "%s - %s", (three_way_check_dat.str()).c_str(), "NULL port scan detected");
return;
}
}
*/
/*
* if we are here that means that none of the
* previous checks yielded anything, but we will
* keep track of the data in SCANNED_PORTS_CNT_DICT anyway
*
* But we ignore locally bound ip addr's if that flag is set
*/
if (IGNORE_WHITE_LISTED_IP_ADDRS) {
if (!is_white_listed_ip_addr(src_ip)) {
add_to_scanned_ports_dict(src_ip, dst_port);
}
}
//std::cout << "WTF1 -" << three_way_check_dat.str() << std::endl << reverse_three_way_check_dat.str() << std::endl << src_ip_dst_ip_dat.str() << std::endl << reverse_src_ip_dst_ip_dat.str() << "WTF2" << std::endl;
}
void GargoylePscandHandler::add_to_scanned_ports_dict(std::string the_ip, int the_port) {
/*
display_local_ip_addr();
display_scanned_ports_dict();
*/
/*
* SCANNED_PORTS_CNT_DICT example:
* 192.168.1.115:64 :: 2 :: 1482869817
* 192.168.1.117:5558 :: 11 :: 1482869646
* 192.168.1.117:5559 :: 4 :: 1482869673
*
*
* structure is:
*
* key = ip:port
* value = hit_count:last_timestamp
*/
if (IGNORE_WHITE_LISTED_IP_ADDRS) {
if (is_white_listed_ip_addr(the_ip) == true) {
return;
}
}
if (the_ip.size() > 0 && the_port > 0) {
/*
* we ignore ephemeral ports as blocking them will disrupt
* legitimate functionality on the running host
*/
//if (the_port < EPHEMERAL_LOW || the_port > EPHEMERAL_HIGH) {
if (!ignore_this_port(the_port)) {
int tstamp = (int) time(NULL);
std::ostringstream tkey;
tkey << the_ip << ":" << the_port;
if (is_in_scanned_ports_cnt_dict(tkey.str())) {
std::pair <int,int> foo;
foo = SCANNED_PORTS_CNT_DICT[tkey.str()];
//std::cout << foo.first << " - " << foo.second << std::endl;
//std::cout << "REPLACING - " << tkey.str() << std::endl;
std::pair <int, int> cnt_tstamp;
cnt_tstamp = std::make_pair (foo.first + 1, tstamp);
SCANNED_PORTS_CNT_DICT[tkey.str()] = cnt_tstamp;
} else {
//std::cout << "ADDING - " << tkey.str() << std::endl;
std::pair <int, int> cnt_tstamp;
cnt_tstamp = std::make_pair (1, tstamp);
SCANNED_PORTS_CNT_DICT.insert(std::make_pair(tkey.str(), cnt_tstamp));
}
}
}
}
void GargoylePscandHandler::set_ignore_local_ip_addrs(bool val) {
IGNORE_WHITE_LISTED_IP_ADDRS = val;
}
void GargoylePscandHandler::set_ephemeral_low(size_t val) {
if (val)
EPHEMERAL_LOW = val;
}
void GargoylePscandHandler::set_ephemeral_high(size_t val) {
if (val)
EPHEMERAL_HIGH = val;
}
void GargoylePscandHandler::clear_three_way_check_dat() {
three_way_check_dat.str("");
three_way_check_dat.clear();
}
void GargoylePscandHandler::clear_reverse_three_way_check_dat() {
reverse_three_way_check_dat.str("");
reverse_three_way_check_dat.clear();
}
void GargoylePscandHandler::clear_src_ip_dst_ip_dat() {
src_ip_dst_ip_dat.str("");
src_ip_dst_ip_dat.clear();
}
void GargoylePscandHandler::clear_reverse_src_ip_dst_ip_dat() {
reverse_src_ip_dst_ip_dat.str("");
reverse_src_ip_dst_ip_dat.clear();
}
void GargoylePscandHandler::display_scanned_ports_dict() {
std::map< std::string, std::pair <int, int> >::iterator it = SCANNED_PORTS_CNT_DICT.begin();
while(it != SCANNED_PORTS_CNT_DICT.end()) {
std::cout << it->first << " :: " << it->second.first << " :: " << it->second.second << std::endl;
it++;
}
std::cout << std::endl << std::endl;
}
void GargoylePscandHandler::display_hot_ports() {
for (std::vector<int>::const_iterator i = HOT_PORTS.begin(); i != HOT_PORTS.end(); ++i) {
std::cout << *i << " ";
}
std::cout << std::endl << std::endl;
}
void GargoylePscandHandler::set_chain_name(std::string s) {
if (s.size() > 0)
CHAIN_NAME = s;
}
void GargoylePscandHandler::add_block_rule(std::string the_ip, int detection_type) {
if (the_ip.size() > 0) {
// don't process internally bound ip addresses
if (IGNORE_WHITE_LISTED_IP_ADDRS) {
if (is_white_listed_ip_addr(the_ip) == true) {
if (is_in_black_listed_hosts(the_ip)) {
BLACK_LISTED_HOSTS.erase(the_ip);
}
return;
}
}
std::set<std::string> ip_tables_entries;
std::set<std::string>::iterator it;
/*
const char *tok1 = ">";
char *token1;
char *token1_save;
*/
const char *tok1 = "\n";
char *token1;
char *token1_save;
/*
int resp;
size_t dst_buf_sz = SMALL_DEST_BUF;
char *l_hosts = (char*) malloc(dst_buf_sz+1);
size_t dst_buf_sz1 = LOCAL_BUF_SZ;
char *host_ip = (char*) malloc(dst_buf_sz1+1);
*/
int added_host_ix = 0;
int tstamp;
size_t d_buf_sz = DEST_BUF_SZ * 2;
char *l_hosts = (char*) malloc(d_buf_sz);
*l_hosts = 0;
size_t dst_buf_sz1 = LOCAL_BUF_SZ;
char *host_ip = (char*) malloc(dst_buf_sz1+1);
*host_ip = 0;
const char *dash_dash = "-- ";
size_t dash_dash_len = 4;
const char *w_space = " ";
char *s_lchains3;
char *s_lchains4;
// whats active in iptables?
iptables_list_chain(GARGOYLE_CHAIN_NAME, l_hosts, d_buf_sz, IPTABLES_SUPPORTS_XLOCK);
if (l_hosts) {
token1 = strtok_r(l_hosts, tok1, &token1_save);
while (token1 != NULL) {
s_lchains3 = strstr (token1, dash_dash);
if (s_lchains3) {
size_t position1 = s_lchains3 - token1;
s_lchains4 = strstr (token1 + position1 + dash_dash_len, w_space);
size_t position2 = s_lchains4 - token1;
*host_ip = 0;
if (bayshoresubstring(position1 + dash_dash_len, position2, token1, host_ip, 16)) {
ip_tables_entries.insert(host_ip);
}
}
token1 = strtok_r(NULL, tok1, &token1_save);
}
}
if (ip_tables_entries.count(the_ip) == 0) {
/*
* !! ENFORCE - if ip in question has been flagged as doing
* something blatantly stupid then block this bitch
*/
added_host_ix = do_block_actions(the_ip, detection_type, DB_LOCATION, IPTABLES_SUPPORTS_XLOCK, ENFORCE, (void *)gargoyle_whitelist_shm);
if (is_in_black_listed_hosts(the_ip) == true) {
BLACK_LISTED_HOSTS.erase(the_ip);
}
}
free(l_hosts);
free(host_ip);
}
}
int GargoylePscandHandler::add_ip_to_hosts_table(std::string the_ip) {
int added_host_ix;
added_host_ix = 0;
if (the_ip.size() > 0) {
// add blacklisted ip to db
/*
* if add_host is successful then it returns
* the ix of the DB row it added. Otherwise
* it returns 0 (zero) or -1. if -1 is returned then
* there is probably an existing record for the
* ip addr in question, so try to get its ix
* value via get_host
*/
added_host_ix = add_host(the_ip.c_str(), DB_LOCATION.c_str());
// already exists
if (added_host_ix == -1) {
// get existing index
added_host_ix = get_host_ix(the_ip.c_str(), DB_LOCATION.c_str());
}
}
return added_host_ix;
}
int GargoylePscandHandler::xmas_scan(
std::string src_ip,
int src_port,
std::string dst_ip,
int dst_port,
int seq_num,
int ack_num,
std::vector<int> tcp_flags) {
if (!ignore_this_port(dst_port) || !is_white_listed_ip_addr(src_ip)) {
if((tcp_flags.size() == 3) &&
(std::find(tcp_flags.begin(), tcp_flags.end(), 1) != tcp_flags.end()) &&
(std::find(tcp_flags.begin(), tcp_flags.end(), 8) != tcp_flags.end()) &&
(std::find(tcp_flags.begin(), tcp_flags.end(), 32) != tcp_flags.end())) { // flags = FIN,URG,PSH - len flags = 3
if (ADD_RULES_KNOWN_SCAN_AGGRESSIVE) {
add_block_rule(src_ip, 3);
int host_ix = add_ip_to_hosts_table(src_ip);
if (host_ix > 0) {
add_to_hosts_port_table(src_ip, dst_port, 1, DB_LOCATION);
}
}
add_to_scanned_ports_dict(dst_ip, src_port);
if (!is_in_black_listed_hosts(src_ip)) {
BLACK_LISTED_HOSTS.insert(src_ip);
}
return 0;
}
}
return 1;
}
int GargoylePscandHandler::fin_scan(
std::string src_ip,
int src_port,
std::string dst_ip,
int dst_port,
int seq_num,
int ack_num,
std::vector<int> tcp_flags) {
if (!ignore_this_port(dst_port) || !is_white_listed_ip_addr(src_ip)) {
if (!is_in_three_way_handshake(three_way_check_dat.str())) {
if(tcp_flags.size() == 1 && tcp_flags[0] == 1) { // flags = FIN - len flags = 1
if (ADD_RULES_KNOWN_SCAN_AGGRESSIVE) {
add_block_rule(src_ip, 2);