mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
400 lines
13 KiB
C++
400 lines
13 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/analysis/ViewPureChecker.h>
|
|
|
|
#include <libevmasm/SemanticInformation.h>
|
|
|
|
#include <libsolidity/inlineasm/AsmData.h>
|
|
#include <libsolidity/ast/ExperimentalFeatures.h>
|
|
|
|
#include <functional>
|
|
|
|
using namespace std;
|
|
using namespace dev;
|
|
using namespace dev::solidity;
|
|
|
|
namespace
|
|
{
|
|
|
|
class AssemblyViewPureChecker: public boost::static_visitor<void>
|
|
{
|
|
public:
|
|
explicit AssemblyViewPureChecker(std::function<void(StateMutability, SourceLocation const&)> _reportMutability):
|
|
m_reportMutability(_reportMutability) {}
|
|
|
|
void operator()(assembly::Label const&) { }
|
|
void operator()(assembly::Instruction const& _instruction)
|
|
{
|
|
checkInstruction(_instruction.location, _instruction.instruction);
|
|
}
|
|
void operator()(assembly::Literal const&) {}
|
|
void operator()(assembly::Identifier const&) {}
|
|
void operator()(assembly::FunctionalInstruction const& _instr)
|
|
{
|
|
checkInstruction(_instr.location, _instr.instruction);
|
|
for (auto const& arg: _instr.arguments)
|
|
boost::apply_visitor(*this, arg);
|
|
}
|
|
void operator()(assembly::ExpressionStatement const& _expr)
|
|
{
|
|
boost::apply_visitor(*this, _expr.expression);
|
|
}
|
|
void operator()(assembly::StackAssignment const&) {}
|
|
void operator()(assembly::Assignment const& _assignment)
|
|
{
|
|
boost::apply_visitor(*this, *_assignment.value);
|
|
}
|
|
void operator()(assembly::VariableDeclaration const& _varDecl)
|
|
{
|
|
if (_varDecl.value)
|
|
boost::apply_visitor(*this, *_varDecl.value);
|
|
}
|
|
void operator()(assembly::FunctionDefinition const& _funDef)
|
|
{
|
|
(*this)(_funDef.body);
|
|
}
|
|
void operator()(assembly::FunctionCall const& _funCall)
|
|
{
|
|
for (auto const& arg: _funCall.arguments)
|
|
boost::apply_visitor(*this, arg);
|
|
}
|
|
void operator()(assembly::If const& _if)
|
|
{
|
|
boost::apply_visitor(*this, *_if.condition);
|
|
(*this)(_if.body);
|
|
}
|
|
void operator()(assembly::Switch const& _switch)
|
|
{
|
|
boost::apply_visitor(*this, *_switch.expression);
|
|
for (auto const& _case: _switch.cases)
|
|
{
|
|
if (_case.value)
|
|
(*this)(*_case.value);
|
|
(*this)(_case.body);
|
|
}
|
|
}
|
|
void operator()(assembly::ForLoop const& _for)
|
|
{
|
|
(*this)(_for.pre);
|
|
boost::apply_visitor(*this, *_for.condition);
|
|
(*this)(_for.body);
|
|
(*this)(_for.post);
|
|
}
|
|
void operator()(assembly::Block const& _block)
|
|
{
|
|
for (auto const& s: _block.statements)
|
|
boost::apply_visitor(*this, s);
|
|
}
|
|
|
|
private:
|
|
std::function<void(StateMutability, SourceLocation const&)> m_reportMutability;
|
|
void checkInstruction(SourceLocation _location, solidity::Instruction _instruction)
|
|
{
|
|
if (eth::SemanticInformation::invalidInViewFunctions(_instruction))
|
|
m_reportMutability(StateMutability::NonPayable, _location);
|
|
else if (eth::SemanticInformation::invalidInPureFunctions(_instruction))
|
|
m_reportMutability(StateMutability::View, _location);
|
|
}
|
|
};
|
|
|
|
}
|
|
|
|
bool ViewPureChecker::check()
|
|
{
|
|
vector<ContractDefinition const*> contracts;
|
|
|
|
for (auto const& node: m_ast)
|
|
{
|
|
SourceUnit const* source = dynamic_cast<SourceUnit const*>(node.get());
|
|
solAssert(source, "");
|
|
contracts += source->filteredNodes<ContractDefinition>(source->nodes());
|
|
}
|
|
|
|
// Check modifiers first to infer their state mutability.
|
|
for (auto const& contract: contracts)
|
|
for (ModifierDefinition const* mod: contract->functionModifiers())
|
|
mod->accept(*this);
|
|
|
|
for (auto const& contract: contracts)
|
|
contract->accept(*this);
|
|
|
|
return !m_errors;
|
|
}
|
|
|
|
|
|
|
|
bool ViewPureChecker::visit(FunctionDefinition const& _funDef)
|
|
{
|
|
solAssert(!m_currentFunction, "");
|
|
m_currentFunction = &_funDef;
|
|
m_bestMutabilityAndLocation = {StateMutability::Pure, _funDef.location()};
|
|
return true;
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(FunctionDefinition const& _funDef)
|
|
{
|
|
solAssert(m_currentFunction == &_funDef, "");
|
|
if (
|
|
m_bestMutabilityAndLocation.mutability < _funDef.stateMutability() &&
|
|
_funDef.stateMutability() != StateMutability::Payable &&
|
|
_funDef.isImplemented() &&
|
|
!_funDef.isConstructor() &&
|
|
!_funDef.isFallback() &&
|
|
!_funDef.annotation().superFunction
|
|
)
|
|
m_errorReporter.warning(
|
|
_funDef.location(),
|
|
"Function state mutability can be restricted to " + stateMutabilityToString(m_bestMutabilityAndLocation.mutability)
|
|
);
|
|
m_currentFunction = nullptr;
|
|
}
|
|
|
|
bool ViewPureChecker::visit(ModifierDefinition const& _modifier)
|
|
{
|
|
solAssert(m_currentFunction == nullptr, "");
|
|
m_bestMutabilityAndLocation = {StateMutability::Pure, _modifier.location()};
|
|
return true;
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(ModifierDefinition const& _modifierDef)
|
|
{
|
|
solAssert(m_currentFunction == nullptr, "");
|
|
m_inferredMutability[&_modifierDef] = std::move(m_bestMutabilityAndLocation);
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(Identifier const& _identifier)
|
|
{
|
|
Declaration const* declaration = _identifier.annotation().referencedDeclaration;
|
|
solAssert(declaration, "");
|
|
|
|
StateMutability mutability = StateMutability::Pure;
|
|
|
|
bool writes = _identifier.annotation().lValueRequested;
|
|
if (VariableDeclaration const* varDecl = dynamic_cast<VariableDeclaration const*>(declaration))
|
|
{
|
|
if (varDecl->isStateVariable() && !varDecl->isConstant())
|
|
mutability = writes ? StateMutability::NonPayable : StateMutability::View;
|
|
}
|
|
else if (MagicVariableDeclaration const* magicVar = dynamic_cast<MagicVariableDeclaration const*>(declaration))
|
|
{
|
|
switch (magicVar->type()->category())
|
|
{
|
|
case Type::Category::Contract:
|
|
solAssert(_identifier.name() == "this" || _identifier.name() == "super", "");
|
|
if (!dynamic_cast<ContractType const&>(*magicVar->type()).isSuper())
|
|
// reads the address
|
|
mutability = StateMutability::View;
|
|
break;
|
|
case Type::Category::Integer:
|
|
solAssert(_identifier.name() == "now", "");
|
|
mutability = StateMutability::View;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
reportMutability(mutability, _identifier.location());
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(InlineAssembly const& _inlineAssembly)
|
|
{
|
|
AssemblyViewPureChecker{
|
|
[=](StateMutability _mutability, SourceLocation const& _location) { reportMutability(_mutability, _location); }
|
|
}(_inlineAssembly.operations());
|
|
}
|
|
|
|
void ViewPureChecker::reportMutability(
|
|
StateMutability _mutability,
|
|
SourceLocation const& _location,
|
|
boost::optional<SourceLocation> const& _nestedLocation
|
|
)
|
|
{
|
|
if (_mutability > m_bestMutabilityAndLocation.mutability)
|
|
m_bestMutabilityAndLocation = MutabilityAndLocation{_mutability, _location};
|
|
if (!m_currentFunction || _mutability <= m_currentFunction->stateMutability())
|
|
return;
|
|
|
|
// Check for payable here, because any occurrence of `msg.value`
|
|
// will set mutability to payable.
|
|
if (_mutability == StateMutability::View || (
|
|
_mutability == StateMutability::Payable &&
|
|
m_currentFunction->stateMutability() == StateMutability::Pure
|
|
))
|
|
{
|
|
m_errorReporter.typeError(
|
|
_location,
|
|
"Function declared as pure, but this expression (potentially) reads from the "
|
|
"environment or state and thus requires \"view\"."
|
|
);
|
|
m_errors = true;
|
|
}
|
|
else if (_mutability == StateMutability::NonPayable)
|
|
{
|
|
m_errorReporter.typeError(
|
|
_location,
|
|
"Function declared as " +
|
|
stateMutabilityToString(m_currentFunction->stateMutability()) +
|
|
", but this expression (potentially) modifies the state and thus "
|
|
"requires non-payable (the default) or payable."
|
|
);
|
|
m_errors = true;
|
|
}
|
|
else if (_mutability == StateMutability::Payable)
|
|
{
|
|
// We do not warn for library functions because they cannot be payable anyway.
|
|
// Also internal functions should be allowed to use `msg.value`.
|
|
if (m_currentFunction->isPublic() && m_currentFunction->inContractKind() != ContractDefinition::ContractKind::Library)
|
|
{
|
|
if (_nestedLocation)
|
|
m_errorReporter.typeError(
|
|
_location,
|
|
SecondarySourceLocation().append("\"msg.value\" appears here inside the modifier.", *_nestedLocation),
|
|
"This modifier uses \"msg.value\" and thus the function has to be payable or internal."
|
|
);
|
|
else
|
|
m_errorReporter.typeError(
|
|
_location,
|
|
"\"msg.value\" can only be used in payable public functions. Make the function "
|
|
"\"payable\" or use an internal function to avoid this error."
|
|
);
|
|
m_errors = true;
|
|
}
|
|
}
|
|
else
|
|
solAssert(false, "");
|
|
|
|
solAssert(
|
|
m_currentFunction->stateMutability() == StateMutability::View ||
|
|
m_currentFunction->stateMutability() == StateMutability::Pure ||
|
|
m_currentFunction->stateMutability() == StateMutability::NonPayable,
|
|
""
|
|
);
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(FunctionCall const& _functionCall)
|
|
{
|
|
if (_functionCall.annotation().kind != FunctionCallKind::FunctionCall)
|
|
return;
|
|
|
|
StateMutability mut = dynamic_cast<FunctionType const&>(*_functionCall.expression().annotation().type).stateMutability();
|
|
// We only require "nonpayable" to call a payble function.
|
|
if (mut == StateMutability::Payable)
|
|
mut = StateMutability::NonPayable;
|
|
reportMutability(mut, _functionCall.location());
|
|
}
|
|
|
|
bool ViewPureChecker::visit(MemberAccess const& _memberAccess)
|
|
{
|
|
// Catch the special case of `this.f.selector` which is a pure expression.
|
|
ASTString const& member = _memberAccess.memberName();
|
|
if (
|
|
_memberAccess.expression().annotation().type->category() == Type::Category::Function &&
|
|
member == "selector"
|
|
)
|
|
if (auto const* expr = dynamic_cast<MemberAccess const*>(&_memberAccess.expression()))
|
|
if (auto const* exprInt = dynamic_cast<Identifier const*>(&expr->expression()))
|
|
if (exprInt->name() == "this")
|
|
// Do not continue visiting.
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(MemberAccess const& _memberAccess)
|
|
{
|
|
StateMutability mutability = StateMutability::Pure;
|
|
bool writes = _memberAccess.annotation().lValueRequested;
|
|
|
|
ASTString const& member = _memberAccess.memberName();
|
|
switch (_memberAccess.expression().annotation().type->category())
|
|
{
|
|
case Type::Category::Address:
|
|
if (member == "balance")
|
|
mutability = StateMutability::View;
|
|
break;
|
|
case Type::Category::Magic:
|
|
{
|
|
using MagicMember = pair<MagicType::Kind, string>;
|
|
set<MagicMember> static const pureMembers{
|
|
{MagicType::Kind::ABI, "decode"},
|
|
{MagicType::Kind::ABI, "encode"},
|
|
{MagicType::Kind::ABI, "encodePacked"},
|
|
{MagicType::Kind::ABI, "encodeWithSelector"},
|
|
{MagicType::Kind::ABI, "encodeWithSignature"},
|
|
{MagicType::Kind::Block, "blockhash"},
|
|
{MagicType::Kind::Message, "data"},
|
|
{MagicType::Kind::Message, "sig"}
|
|
};
|
|
set<MagicMember> static const payableMembers{
|
|
{MagicType::Kind::Message, "value"}
|
|
};
|
|
|
|
auto const& type = dynamic_cast<MagicType const&>(*_memberAccess.expression().annotation().type);
|
|
MagicMember magicMember(type.kind(), member);
|
|
|
|
if (!pureMembers.count(magicMember))
|
|
mutability = StateMutability::View;
|
|
if (payableMembers.count(magicMember))
|
|
mutability = StateMutability::Payable;
|
|
break;
|
|
}
|
|
case Type::Category::Struct:
|
|
{
|
|
if (_memberAccess.expression().annotation().type->dataStoredIn(DataLocation::Storage))
|
|
mutability = writes ? StateMutability::NonPayable : StateMutability::View;
|
|
break;
|
|
}
|
|
case Type::Category::Array:
|
|
{
|
|
auto const& type = dynamic_cast<ArrayType const&>(*_memberAccess.expression().annotation().type);
|
|
if (member == "length" && type.isDynamicallySized() && type.dataStoredIn(DataLocation::Storage))
|
|
mutability = writes ? StateMutability::NonPayable : StateMutability::View;
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
reportMutability(mutability, _memberAccess.location());
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(IndexAccess const& _indexAccess)
|
|
{
|
|
if (!_indexAccess.indexExpression())
|
|
solAssert(_indexAccess.annotation().type->category() == Type::Category::TypeType, "");
|
|
else
|
|
{
|
|
bool writes = _indexAccess.annotation().lValueRequested;
|
|
if (_indexAccess.baseExpression().annotation().type->dataStoredIn(DataLocation::Storage))
|
|
reportMutability(writes ? StateMutability::NonPayable : StateMutability::View, _indexAccess.location());
|
|
}
|
|
}
|
|
|
|
void ViewPureChecker::endVisit(ModifierInvocation const& _modifier)
|
|
{
|
|
solAssert(_modifier.name(), "");
|
|
if (ModifierDefinition const* mod = dynamic_cast<decltype(mod)>(_modifier.name()->annotation().referencedDeclaration))
|
|
{
|
|
solAssert(m_inferredMutability.count(mod), "");
|
|
auto const& mutAndLocation = m_inferredMutability.at(mod);
|
|
reportMutability(mutAndLocation.mutability, _modifier.location(), mutAndLocation.location);
|
|
}
|
|
else
|
|
solAssert(dynamic_cast<ContractDefinition const*>(_modifier.name()->annotation().referencedDeclaration), "");
|
|
}
|
|
|