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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#include <config.h>
#include <cassert>
#include <iostream>
#include <random>
#include <Common.hpp>
#include <Protocol.hpp>
#include <Unit.hpp>
#include <Util.hpp>
#include <Poco/Net/HTTPServerRequest.h>
// Inside the WSD process
class UnitFuzz : public UnitWSD
{
std::random_device _rd;
std::mt19937 _mt;
std::uniform_int_distribution<> _dist;
public:
UnitFuzz() :
UnitWSD("fuzz"),
_mt(_rd()),
_dist(0, 1000)
{
std::cerr << "\n\nYour WSD process is being randomly fuzzed\n\n\n";
setHasKitHooks();
setTimeout(std::chrono::hours(1));
}
std::string corruptString(const std::string &str)
{
std::string ret;
for (auto it = str.begin(); it != str.end(); ++it)
{
int op = _dist(_mt);
if (op < 10) {
switch (op) {
case 0:
ret += 0xff;
break;
case 1:
case 3:
ret += *it & 0x80;
break;
default:
ret += *it ^ _dist(_mt);
break;
}
}
}
return ret;
}
/*
* Note: Fuzzers are fragile and their performance is rather
* sensitive. Please avoid random code tweaking in this method.
*/
virtual bool filterSessionInput(Session *, const char *buffer,
int length,
std::unique_ptr< std::vector<char> > &replace) override
{
// Avoid fuzzing most messages
if (_dist(_mt) < 875)
return false;
std::unique_ptr<std::vector<char>> fuzzed(new std::vector<char>());
fuzzed->assign(buffer, buffer+length);
int resize = _dist(_mt);
if (resize < 50) { // truncate
size_t shrink = (fuzzed->size() * _dist(_mt))/1000;
fuzzed->resize(shrink);
} else if (resize < 200) {
bool prepend = resize < 100;
bool middle = resize < 150;
size_t count = 1 + _dist(_mt)/100;
for (size_t i = 0; i < count; ++i)
{
char c = (_dist(_mt) * 256 / 1000);
if (prepend)
fuzzed->insert(fuzzed->begin(), c);
else if (middle)
fuzzed->insert(fuzzed->begin() + fuzzed->size()/2, c);
else
fuzzed->push_back(c);
}
}
int numCorrupt = (_dist(_mt) / 100) - 75;
for (int i = 0; i < numCorrupt; ++i)
{
size_t offset = (_dist(_mt) * fuzzed->size() - 1) / 1000;
char c = (*fuzzed)[offset];
int change = _dist(_mt);
if (change < 256)
c ^= change;
else if (c >= '0' && c <= '9')
c = '0' + (change - 256)/100;
else
c |= 0x80;
}
replace = std::move(fuzzed);
return true;
}
};
// Inside the forkit & kit processes
class UnitKitFuzz : public UnitKit
{
public:
UnitKitFuzz() : UnitKit("fuzz")
{
std::cerr << "\n\nYour Kit process has fuzzing hooks\n\n\n";
setTimeout(std::chrono::hours(1));
}
virtual bool filterKitMessage(WebSocketHandler *, std::string & /* message */) override
{
return false;
}
};
UnitBase *unit_create_wsd(void)
{
return new UnitFuzz();
}
UnitBase *unit_create_kit(void)
{
return new UnitKitFuzz();
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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