mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
302 lines
8.9 KiB
C++
302 lines
8.9 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/>.
|
|
*/
|
|
/**
|
|
* @author Federico Bond <federicobond@gmail.com>
|
|
* @date 2016
|
|
* Static analyzer and checker.
|
|
*/
|
|
|
|
#include <libsolidity/analysis/StaticAnalyzer.h>
|
|
#include <libsolidity/analysis/ConstantEvaluator.h>
|
|
#include <libsolidity/ast/AST.h>
|
|
#include <libsolidity/interface/ErrorReporter.h>
|
|
#include <memory>
|
|
|
|
using namespace std;
|
|
using namespace dev;
|
|
using namespace dev::solidity;
|
|
|
|
bool StaticAnalyzer::analyze(SourceUnit const& _sourceUnit)
|
|
{
|
|
_sourceUnit.accept(*this);
|
|
return Error::containsOnlyWarnings(m_errorReporter.errors());
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(ContractDefinition const& _contract)
|
|
{
|
|
m_library = _contract.isLibrary();
|
|
m_currentContract = &_contract;
|
|
return true;
|
|
}
|
|
|
|
void StaticAnalyzer::endVisit(ContractDefinition const&)
|
|
{
|
|
m_library = false;
|
|
m_currentContract = nullptr;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(FunctionDefinition const& _function)
|
|
{
|
|
const bool isInterface = m_currentContract->contractKind() == ContractDefinition::ContractKind::Interface;
|
|
|
|
if (_function.noVisibilitySpecified())
|
|
m_errorReporter.warning(
|
|
_function.location(),
|
|
"No visibility specified. Defaulting to \"" +
|
|
Declaration::visibilityToString(_function.visibility()) +
|
|
"\"." +
|
|
(isInterface ? " In interfaces it defaults to external." : "")
|
|
);
|
|
if (_function.isImplemented())
|
|
m_currentFunction = &_function;
|
|
else
|
|
solAssert(!m_currentFunction, "");
|
|
solAssert(m_localVarUseCount.empty(), "");
|
|
m_nonPayablePublic = _function.isPublic() && !_function.isPayable();
|
|
m_constructor = _function.isConstructor();
|
|
return true;
|
|
}
|
|
|
|
void StaticAnalyzer::endVisit(FunctionDefinition const&)
|
|
{
|
|
m_currentFunction = nullptr;
|
|
m_nonPayablePublic = false;
|
|
m_constructor = false;
|
|
for (auto const& var: m_localVarUseCount)
|
|
if (var.second == 0)
|
|
{
|
|
if (var.first.second->isCallableParameter())
|
|
m_errorReporter.warning(
|
|
var.first.second->location(),
|
|
"Unused function parameter. Remove or comment out the variable name to silence this warning."
|
|
);
|
|
else
|
|
m_errorReporter.warning(var.first.second->location(), "Unused local variable.");
|
|
}
|
|
|
|
m_localVarUseCount.clear();
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(Identifier const& _identifier)
|
|
{
|
|
if (m_currentFunction)
|
|
if (auto var = dynamic_cast<VariableDeclaration const*>(_identifier.annotation().referencedDeclaration))
|
|
{
|
|
solAssert(!var->name().empty(), "");
|
|
if (var->isLocalVariable())
|
|
m_localVarUseCount[make_pair(var->id(), var)] += 1;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(VariableDeclaration const& _variable)
|
|
{
|
|
if (m_currentFunction)
|
|
{
|
|
solAssert(_variable.isLocalVariable(), "");
|
|
if (_variable.name() != "")
|
|
// This is not a no-op, the entry might pre-exist.
|
|
m_localVarUseCount[make_pair(_variable.id(), &_variable)] += 0;
|
|
}
|
|
else if (_variable.isStateVariable())
|
|
{
|
|
set<StructDefinition const*> structsSeen;
|
|
if (structureSizeEstimate(*_variable.type(), structsSeen) >= bigint(1) << 64)
|
|
m_errorReporter.warning(
|
|
_variable.location(),
|
|
"Variable covers a large part of storage and thus makes collisions likely. "
|
|
"Either use mappings or dynamic arrays and allow their size to be increased only "
|
|
"in small quantities per transaction."
|
|
);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(Return const& _return)
|
|
{
|
|
// If the return has an expression, it counts as
|
|
// a "use" of the return parameters.
|
|
if (m_currentFunction && _return.expression())
|
|
for (auto const& var: m_currentFunction->returnParameters())
|
|
if (!var->name().empty())
|
|
m_localVarUseCount[make_pair(var->id(), var.get())] += 1;
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(ExpressionStatement const& _statement)
|
|
{
|
|
if (_statement.expression().annotation().isPure)
|
|
m_errorReporter.warning(
|
|
_statement.location(),
|
|
"Statement has no effect."
|
|
);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(MemberAccess const& _memberAccess)
|
|
{
|
|
if (MagicType const* type = dynamic_cast<MagicType const*>(_memberAccess.expression().annotation().type.get()))
|
|
{
|
|
if (type->kind() == MagicType::Kind::Message && _memberAccess.memberName() == "gas")
|
|
m_errorReporter.typeError(
|
|
_memberAccess.location(),
|
|
"\"msg.gas\" has been deprecated in favor of \"gasleft()\""
|
|
);
|
|
else if (type->kind() == MagicType::Kind::Block && _memberAccess.memberName() == "blockhash")
|
|
m_errorReporter.typeError(
|
|
_memberAccess.location(),
|
|
"\"block.blockhash()\" has been deprecated in favor of \"blockhash()\""
|
|
);
|
|
}
|
|
|
|
if (m_nonPayablePublic && !m_library)
|
|
if (MagicType const* type = dynamic_cast<MagicType const*>(_memberAccess.expression().annotation().type.get()))
|
|
if (type->kind() == MagicType::Kind::Message && _memberAccess.memberName() == "value")
|
|
m_errorReporter.warning(
|
|
_memberAccess.location(),
|
|
"\"msg.value\" used in non-payable function. Do you want to add the \"payable\" modifier to this function?"
|
|
);
|
|
|
|
if (_memberAccess.memberName() == "callcode")
|
|
if (auto const* type = dynamic_cast<FunctionType const*>(_memberAccess.annotation().type.get()))
|
|
if (type->kind() == FunctionType::Kind::BareCallCode)
|
|
m_errorReporter.typeError(
|
|
_memberAccess.location(),
|
|
"\"callcode\" has been deprecated in favour of \"delegatecall\"."
|
|
);
|
|
|
|
if (m_constructor)
|
|
{
|
|
auto const* expr = &_memberAccess.expression();
|
|
while(expr)
|
|
{
|
|
if (auto id = dynamic_cast<Identifier const*>(expr))
|
|
{
|
|
if (id->name() == "this")
|
|
m_errorReporter.warning(
|
|
id->location(),
|
|
"\"this\" used in constructor. "
|
|
"Note that external functions of a contract "
|
|
"cannot be called while it is being constructed.");
|
|
break;
|
|
}
|
|
else if (auto tuple = dynamic_cast<TupleExpression const*>(expr))
|
|
{
|
|
if (tuple->components().size() == 1)
|
|
expr = tuple->components().front().get();
|
|
else
|
|
break;
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(InlineAssembly const& _inlineAssembly)
|
|
{
|
|
if (!m_currentFunction)
|
|
return true;
|
|
|
|
for (auto const& ref: _inlineAssembly.annotation().externalReferences)
|
|
{
|
|
if (auto var = dynamic_cast<VariableDeclaration const*>(ref.second.declaration))
|
|
{
|
|
solAssert(!var->name().empty(), "");
|
|
if (var->isLocalVariable())
|
|
m_localVarUseCount[make_pair(var->id(), var)] += 1;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(BinaryOperation const& _operation)
|
|
{
|
|
if (
|
|
_operation.rightExpression().annotation().isPure &&
|
|
(_operation.getOperator() == Token::Div || _operation.getOperator() == Token::Mod)
|
|
)
|
|
if (auto rhs = dynamic_pointer_cast<RationalNumberType const>(
|
|
ConstantEvaluator(m_errorReporter).evaluate(_operation.rightExpression())
|
|
))
|
|
if (rhs->isZero())
|
|
m_errorReporter.typeError(
|
|
_operation.location(),
|
|
(_operation.getOperator() == Token::Div) ? "Division by zero." : "Modulo zero."
|
|
);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool StaticAnalyzer::visit(FunctionCall const& _functionCall)
|
|
{
|
|
if (_functionCall.annotation().kind == FunctionCallKind::FunctionCall)
|
|
{
|
|
auto functionType = dynamic_pointer_cast<FunctionType const>(_functionCall.expression().annotation().type);
|
|
solAssert(functionType, "");
|
|
if (functionType->kind() == FunctionType::Kind::AddMod || functionType->kind() == FunctionType::Kind::MulMod)
|
|
{
|
|
solAssert(_functionCall.arguments().size() == 3, "");
|
|
if (_functionCall.arguments()[2]->annotation().isPure)
|
|
if (auto lastArg = dynamic_pointer_cast<RationalNumberType const>(
|
|
ConstantEvaluator(m_errorReporter).evaluate(*(_functionCall.arguments())[2])
|
|
))
|
|
if (lastArg->isZero())
|
|
m_errorReporter.typeError(
|
|
_functionCall.location(),
|
|
"Arithmetic modulo zero."
|
|
);
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bigint StaticAnalyzer::structureSizeEstimate(Type const& _type, set<StructDefinition const*>& _structsSeen)
|
|
{
|
|
switch (_type.category())
|
|
{
|
|
case Type::Category::Array:
|
|
{
|
|
auto const& t = dynamic_cast<ArrayType const&>(_type);
|
|
return structureSizeEstimate(*t.baseType(), _structsSeen) * (t.isDynamicallySized() ? 1 : t.length());
|
|
}
|
|
case Type::Category::Struct:
|
|
{
|
|
auto const& t = dynamic_cast<StructType const&>(_type);
|
|
bigint size = 1;
|
|
if (!_structsSeen.count(&t.structDefinition()))
|
|
{
|
|
_structsSeen.insert(&t.structDefinition());
|
|
for (auto const& m: t.members(nullptr))
|
|
size += structureSizeEstimate(*m.type, _structsSeen);
|
|
}
|
|
return size;
|
|
}
|
|
case Type::Category::Mapping:
|
|
{
|
|
return structureSizeEstimate(*dynamic_cast<MappingType const&>(_type).valueType(), _structsSeen);
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
return bigint(1);
|
|
}
|