solidity/libsolidity/formal/SMTLib2Interface.cpp
2020-05-14 23:32:29 +02:00

282 lines
7.8 KiB
C++

/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libsolidity/formal/SMTLib2Interface.h>
#include <libsolutil/Keccak256.h>
#include <boost/algorithm/string/join.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <array>
#include <fstream>
#include <iostream>
#include <memory>
#include <stdexcept>
#include <string>
#include <utility>
using namespace std;
using namespace solidity;
using namespace solidity::util;
using namespace solidity::frontend;
using namespace solidity::frontend::smt;
SMTLib2Interface::SMTLib2Interface(
map<h256, string> const& _queryResponses,
ReadCallback::Callback _smtCallback
):
m_queryResponses(_queryResponses),
m_smtCallback(std::move(_smtCallback))
{
reset();
}
void SMTLib2Interface::reset()
{
m_accumulatedOutput.clear();
m_accumulatedOutput.emplace_back();
m_variables.clear();
m_userSorts.clear();
write("(set-option :produce-models true)");
write("(set-logic ALL)");
}
void SMTLib2Interface::push()
{
m_accumulatedOutput.emplace_back();
}
void SMTLib2Interface::pop()
{
solAssert(!m_accumulatedOutput.empty(), "");
m_accumulatedOutput.pop_back();
}
void SMTLib2Interface::declareVariable(string const& _name, SortPointer const& _sort)
{
solAssert(_sort, "");
if (_sort->kind == Kind::Function)
declareFunction(_name, _sort);
else if (!m_variables.count(_name))
{
m_variables.emplace(_name, _sort);
write("(declare-fun |" + _name + "| () " + toSmtLibSort(*_sort) + ')');
}
}
void SMTLib2Interface::declareFunction(string const& _name, SortPointer const& _sort)
{
solAssert(_sort, "");
solAssert(_sort->kind == smt::Kind::Function, "");
// TODO Use domain and codomain as key as well
if (!m_variables.count(_name))
{
auto const& fSort = dynamic_pointer_cast<FunctionSort>(_sort);
string domain = toSmtLibSort(fSort->domain);
string codomain = toSmtLibSort(*fSort->codomain);
m_variables.emplace(_name, _sort);
write(
"(declare-fun |" +
_name +
"| " +
domain +
" " +
codomain +
")"
);
}
}
void SMTLib2Interface::addAssertion(smt::Expression const& _expr)
{
write("(assert " + toSExpr(_expr) + ")");
}
pair<CheckResult, vector<string>> SMTLib2Interface::check(vector<smt::Expression> const& _expressionsToEvaluate)
{
string response = querySolver(
boost::algorithm::join(m_accumulatedOutput, "\n") +
checkSatAndGetValuesCommand(_expressionsToEvaluate)
);
CheckResult result;
// TODO proper parsing
if (boost::starts_with(response, "sat\n"))
result = CheckResult::SATISFIABLE;
else if (boost::starts_with(response, "unsat\n"))
result = CheckResult::UNSATISFIABLE;
else if (boost::starts_with(response, "unknown\n"))
result = CheckResult::UNKNOWN;
else
result = CheckResult::ERROR;
vector<string> values;
if (result == CheckResult::SATISFIABLE && result != CheckResult::ERROR)
values = parseValues(find(response.cbegin(), response.cend(), '\n'), response.cend());
return make_pair(result, values);
}
string SMTLib2Interface::toSExpr(smt::Expression const& _expr)
{
if (_expr.arguments.empty())
return _expr.name;
std::string sexpr = "(";
if (_expr.name == "const_array")
{
solAssert(_expr.arguments.size() == 2, "");
auto sortSort = std::dynamic_pointer_cast<SortSort>(_expr.arguments.at(0).sort);
solAssert(sortSort, "");
auto arraySort = dynamic_pointer_cast<ArraySort>(sortSort->inner);
solAssert(arraySort, "");
sexpr += "(as const " + toSmtLibSort(*arraySort) + ") ";
sexpr += toSExpr(_expr.arguments.at(1));
}
else if (_expr.name == "tuple_get")
{
solAssert(_expr.arguments.size() == 2, "");
auto tupleSort = dynamic_pointer_cast<TupleSort>(_expr.arguments.at(0).sort);
unsigned index = std::stoi(_expr.arguments.at(1).name);
solAssert(index < tupleSort->members.size(), "");
sexpr += "|" + tupleSort->members.at(index) + "| " + toSExpr(_expr.arguments.at(0));
}
else if (_expr.name == "tuple_constructor")
{
auto tupleSort = dynamic_pointer_cast<TupleSort>(_expr.sort);
solAssert(tupleSort, "");
sexpr += "|" + tupleSort->name + "|";
for (auto const& arg: _expr.arguments)
sexpr += " " + toSExpr(arg);
}
else
{
sexpr += _expr.name;
for (auto const& arg: _expr.arguments)
sexpr += " " + toSExpr(arg);
}
sexpr += ")";
return sexpr;
}
string SMTLib2Interface::toSmtLibSort(Sort const& _sort)
{
switch (_sort.kind)
{
case Kind::Int:
return "Int";
case Kind::Bool:
return "Bool";
case Kind::Array:
{
auto const& arraySort = dynamic_cast<ArraySort const&>(_sort);
solAssert(arraySort.domain && arraySort.range, "");
return "(Array " + toSmtLibSort(*arraySort.domain) + ' ' + toSmtLibSort(*arraySort.range) + ')';
}
case Kind::Tuple:
{
auto const& tupleSort = dynamic_cast<TupleSort const&>(_sort);
string tupleName = "|" + tupleSort.name + "|";
if (!m_userSorts.count(tupleName))
{
m_userSorts.insert(tupleName);
string decl("(declare-datatypes ((" + tupleName + " 0)) (((" + tupleName);
solAssert(tupleSort.members.size() == tupleSort.components.size(), "");
for (unsigned i = 0; i < tupleSort.members.size(); ++i)
decl += " (|" + tupleSort.members.at(i) + "| " + toSmtLibSort(*tupleSort.components.at(i)) + ")";
decl += "))))";
write(decl);
}
return tupleName;
}
default:
solAssert(false, "Invalid SMT sort");
}
}
string SMTLib2Interface::toSmtLibSort(vector<SortPointer> const& _sorts)
{
string ssort("(");
for (auto const& sort: _sorts)
ssort += toSmtLibSort(*sort) + " ";
ssort += ")";
return ssort;
}
void SMTLib2Interface::write(string _data)
{
solAssert(!m_accumulatedOutput.empty(), "");
m_accumulatedOutput.back() += move(_data) + "\n";
}
string SMTLib2Interface::checkSatAndGetValuesCommand(vector<smt::Expression> const& _expressionsToEvaluate)
{
string command;
if (_expressionsToEvaluate.empty())
command = "(check-sat)\n";
else
{
// TODO make sure these are unique
for (size_t i = 0; i < _expressionsToEvaluate.size(); i++)
{
auto const& e = _expressionsToEvaluate.at(i);
solAssert(e.sort->kind == Kind::Int || e.sort->kind == Kind::Bool, "Invalid sort for expression to evaluate.");
command += "(declare-const |EVALEXPR_" + to_string(i) + "| " + (e.sort->kind == Kind::Int ? "Int" : "Bool") + ")\n";
command += "(assert (= |EVALEXPR_" + to_string(i) + "| " + toSExpr(e) + "))\n";
}
command += "(check-sat)\n";
command += "(get-value (";
for (size_t i = 0; i < _expressionsToEvaluate.size(); i++)
command += "|EVALEXPR_" + to_string(i) + "| ";
command += "))\n";
}
return command;
}
vector<string> SMTLib2Interface::parseValues(string::const_iterator _start, string::const_iterator _end)
{
vector<string> values;
while (_start < _end)
{
auto valStart = find(_start, _end, ' ');
if (valStart < _end)
++valStart;
auto valEnd = find(valStart, _end, ')');
values.emplace_back(valStart, valEnd);
_start = find(valEnd, _end, '(');
}
return values;
}
string SMTLib2Interface::querySolver(string const& _input)
{
h256 inputHash = keccak256(_input);
if (m_queryResponses.count(inputHash))
return m_queryResponses.at(inputHash);
if (m_smtCallback)
{
auto result = m_smtCallback(ReadCallback::kindString(ReadCallback::Kind::SMTQuery), _input);
if (result.success)
return result.responseOrErrorMessage;
}
m_unhandledQueries.push_back(_input);
return "unknown\n";
}