Beispiel #1
0
def parse_call(expression, caller_context):
    src = expression['src']
    if caller_context.is_compact_ast:
        attributes = expression
        type_conversion = expression['kind'] == 'typeConversion'
        type_return = attributes['typeDescriptions']['typeString']

    else:
        attributes = expression['attributes']
        type_conversion = attributes['type_conversion']
        type_return = attributes['type']

    if type_conversion:
        type_call = parse_type(UnknownType(type_return), caller_context)

        if caller_context.is_compact_ast:
            type_info = expression['expression']
            assert len(expression['arguments']) == 1
            expression_to_parse = expression['arguments'][0]
        else:
            children = expression['children']
            assert len(children) == 2
            type_info = children[0]
            expression_to_parse = children[1]
            assert type_info['name'] in [
                'ElementaryTypenameExpression', 'ElementaryTypeNameExpression',
                'Identifier', 'TupleExpression', 'IndexAccess', 'MemberAccess'
            ]

        expression = parse_expression(expression_to_parse, caller_context)
        t = TypeConversion(expression, type_call)
        t.set_offset(src, caller_context.slither)
        return t

    if caller_context.is_compact_ast:
        called = parse_expression(expression['expression'], caller_context)
        arguments = []
        if expression['arguments']:
            arguments = [
                parse_expression(a, caller_context)
                for a in expression['arguments']
            ]
    else:
        children = expression['children']
        called = parse_expression(children[0], caller_context)
        arguments = [
            parse_expression(a, caller_context) for a in children[1::]
        ]

    if isinstance(called, SuperCallExpression):
        sp = SuperCallExpression(called, arguments, type_return)
        sp.set_offset(expression['src'], caller_context.slither)
        return sp
    call_expression = CallExpression(called, arguments, type_return)
    call_expression.set_offset(src, caller_context.slither)
    return call_expression
Beispiel #2
0
def parse_call(expression, caller_context):
    attributes = expression['attributes']

    type_conversion = attributes['type_conversion']

    children = expression['children']
    if type_conversion:
        assert len(children) == 2

        type_call = parse_type(UnknownType(attributes['type']), caller_context)
        type_info = children[0]
        assert type_info['name'] in [
            'ElementaryTypenameExpression', 'ElementaryTypeNameExpression',
            'Identifier', 'TupleExpression', 'IndexAccess', 'MemberAccess'
        ]

        expression = parse_expression(children[1], caller_context)
        t = TypeConversion(expression, type_call)
        return t

    assert children

    type_call = attributes['type']
    called = parse_expression(children[0], caller_context)
    arguments = [parse_expression(a, caller_context) for a in children[1::]]

    if isinstance(called, SuperCallExpression):
        return SuperCallExpression(called, arguments, type_call)
    return CallExpression(called, arguments, type_call)
Beispiel #3
0
def parse_expression(expression, caller_context):
    """

    Returns:
        str: expression
    """
    #  Expression
    #    = Expression ('++' | '--')
    #    | NewExpression
    #    | IndexAccess
    #    | MemberAccess
    #    | FunctionCall
    #    | '(' Expression ')'
    #    | ('!' | '~' | 'delete' | '++' | '--' | '+' | '-') Expression
    #    | Expression '**' Expression
    #    | Expression ('*' | '/' | '%') Expression
    #    | Expression ('+' | '-') Expression
    #    | Expression ('<<' | '>>') Expression
    #    | Expression '&' Expression
    #    | Expression '^' Expression
    #    | Expression '|' Expression
    #    | Expression ('<' | '>' | '<=' | '>=') Expression
    #    | Expression ('==' | '!=') Expression
    #    | Expression '&&' Expression
    #    | Expression '||' Expression
    #    | Expression '?' Expression ':' Expression
    #    | Expression ('=' | '|=' | '^=' | '&=' | '<<=' | '>>=' | '+=' | '-=' | '*=' | '/=' | '%=') Expression
    #    | PrimaryExpression

    # The AST naming does not follow the spec
    name = expression[caller_context.get_key()]
    is_compact_ast = caller_context.is_compact_ast

    if name == 'UnaryOperation':
        if is_compact_ast:
            attributes = expression
        else:
            attributes = expression['attributes']
        assert 'prefix' in attributes
        operation_type = UnaryOperationType.get_type(attributes['operator'],
                                                     attributes['prefix'])

        if is_compact_ast:
            expression = parse_expression(expression['subExpression'],
                                          caller_context)
        else:
            assert len(expression['children']) == 1
            expression = parse_expression(expression['children'][0],
                                          caller_context)
        unary_op = UnaryOperation(expression, operation_type)
        return unary_op

    elif name == 'BinaryOperation':
        if is_compact_ast:
            attributes = expression
        else:
            attributes = expression['attributes']
        operation_type = BinaryOperationType.get_type(attributes['operator'])

        if is_compact_ast:
            left_expression = parse_expression(expression['leftExpression'],
                                               caller_context)
            right_expression = parse_expression(expression['rightExpression'],
                                                caller_context)
        else:
            assert len(expression['children']) == 2
            left_expression = parse_expression(expression['children'][0],
                                               caller_context)
            right_expression = parse_expression(expression['children'][1],
                                                caller_context)
        binary_op = BinaryOperation(left_expression, right_expression,
                                    operation_type)
        return binary_op

    elif name == 'FunctionCall':
        return parse_call(expression, caller_context)

    elif name == 'TupleExpression':
        """
            For expression like
            (a,,c) = (1,2,3)
            the AST provides only two children in the left side
            We check the type provided (tuple(uint256,,uint256))
            To determine that there is an empty variable
            Otherwhise we would not be able to determine that
            a = 1, c = 3, and 2 is lost

            Note: this is only possible with Solidity >= 0.4.12
        """
        if is_compact_ast:
            expressions = [
                parse_expression(e, caller_context) if e else None
                for e in expression['components']
            ]
        else:
            if 'children' not in expression:
                attributes = expression['attributes']
                components = attributes['components']
                expressions = [
                    parse_expression(c, caller_context) if c else None
                    for c in components
                ]
            else:
                expressions = [
                    parse_expression(e, caller_context)
                    for e in expression['children']
                ]
        # Add none for empty tuple items
        if "attributes" in expression:
            if "type" in expression['attributes']:
                t = expression['attributes']['type']
                if ',,' in t or '(,' in t or ',)' in t:
                    t = t[len('tuple('):-1]
                    elems = t.split(',')
                    for idx in range(len(elems)):
                        if elems[idx] == '':
                            expressions.insert(idx, None)
        t = TupleExpression(expressions)
        return t

    elif name == 'Conditional':
        if is_compact_ast:
            if_expression = parse_expression(expression['condition'],
                                             caller_context)
            then_expression = parse_expression(expression['trueExpression'],
                                               caller_context)
            else_expression = parse_expression(expression['falseExpression'],
                                               caller_context)
        else:
            children = expression['children']
            assert len(children) == 3
            if_expression = parse_expression(children[0], caller_context)
            then_expression = parse_expression(children[1], caller_context)
            else_expression = parse_expression(children[2], caller_context)
        conditional = ConditionalExpression(if_expression, then_expression,
                                            else_expression)
        return conditional

    elif name == 'Assignment':
        if is_compact_ast:
            left_expression = parse_expression(expression['leftHandSide'],
                                               caller_context)
            right_expression = parse_expression(expression['rightHandSide'],
                                                caller_context)

            operation_type = AssignmentOperationType.get_type(
                expression['operator'])

            operation_return_type = expression['typeDescriptions'][
                'typeString']
        else:
            attributes = expression['attributes']
            children = expression['children']
            assert len(expression['children']) == 2
            left_expression = parse_expression(children[0], caller_context)
            right_expression = parse_expression(children[1], caller_context)

            operation_type = AssignmentOperationType.get_type(
                attributes['operator'])
            operation_return_type = attributes['type']

        assignement = AssignmentOperation(left_expression, right_expression,
                                          operation_type,
                                          operation_return_type)
        return assignement

    elif name == 'Literal':
        assert 'children' not in expression

        if is_compact_ast:
            value = expression['value']
            if not value:
                value = '0x' + expression['hexValue']
        else:
            value = expression['attributes']['value']
            if value is None:
                # for literal declared as hex
                # see https://solidity.readthedocs.io/en/v0.4.25/types.html?highlight=hex#hexadecimal-literals
                assert 'hexvalue' in expression['attributes']
                value = '0x' + expression['attributes']['hexvalue']
        literal = Literal(value)
        return literal

    elif name == 'Identifier':
        assert 'children' not in expression

        t = None

        if caller_context.is_compact_ast:
            value = expression['name']
            t = expression['typeDescriptions']['typeString']
        else:
            value = expression['attributes']['value']
            if 'type' in expression['attributes']:
                t = expression['attributes']['type']

        if t:
            found = re.findall(
                '[struct|enum|function|modifier] \(([\[\] ()a-zA-Z0-9\.,_]*)\)',
                t)
            assert len(found) <= 1
            if found:
                value = value + '(' + found[0] + ')'
                value = filter_name(value)

        var = find_variable(value, caller_context)

        identifier = Identifier(var)
        return identifier

    elif name == 'IndexAccess':
        if is_compact_ast:
            index_type = expression['typeDescriptions']['typeString']
            left = expression['baseExpression']
            right = expression['indexExpression']
        else:
            index_type = expression['attributes']['type']
            children = expression['children']
            assert len(children) == 2
            left = children[0]
            right = children[1]
        left_expression = parse_expression(left, caller_context)
        right_expression = parse_expression(right, caller_context)
        index = IndexAccess(left_expression, right_expression, index_type)
        return index

    elif name == 'MemberAccess':
        if caller_context.is_compact_ast:
            member_name = expression['memberName']
            member_type = expression['typeDescriptions']['typeString']
            member_expression = parse_expression(expression['expression'],
                                                 caller_context)
        else:
            member_name = expression['attributes']['member_name']
            member_type = expression['attributes']['type']
            children = expression['children']
            assert len(children) == 1
            member_expression = parse_expression(children[0], caller_context)
        if str(member_expression) == 'super':
            super_name = parse_super_name(expression, is_compact_ast)
            if isinstance(caller_context, Contract):
                inheritance = caller_context.inheritance
            else:
                assert isinstance(caller_context, Function)
                inheritance = caller_context.contract.inheritance
            var = None
            for father in inheritance:
                try:
                    var = find_variable(super_name, father)
                    break
                except VariableNotFound:
                    continue
            if var is None:
                raise VariableNotFound(
                    'Variable not found: {}'.format(super_name))
            return SuperIdentifier(var)
        member_access = MemberAccess(member_name, member_type,
                                     member_expression)
        if str(member_access) in SOLIDITY_VARIABLES_COMPOSED:
            return Identifier(SolidityVariableComposed(str(member_access)))
        return member_access

    elif name == 'ElementaryTypeNameExpression':
        # nop exression
        # uint;
        if is_compact_ast:
            value = expression['typeName']
        else:
            assert 'children' not in expression
            value = expression['attributes']['value']
        t = parse_type(UnknownType(value), caller_context)

        return ElementaryTypeNameExpression(t)

    # NewExpression is not a root expression, it's always the child of another expression
    elif name == 'NewExpression':

        if is_compact_ast:
            type_name = expression['typeName']
        else:
            children = expression['children']
            assert len(children) == 1
            type_name = children[0]

        if type_name[caller_context.get_key()] == 'ArrayTypeName':
            depth = 0
            while type_name[caller_context.get_key()] == 'ArrayTypeName':
                # Note: dont conserve the size of the array if provided
                # We compute it directly
                if is_compact_ast:
                    type_name = type_name['baseType']
                else:
                    type_name = type_name['children'][0]
                depth += 1
            if type_name[caller_context.get_key()] == 'ElementaryTypeName':
                if is_compact_ast:
                    array_type = ElementaryType(type_name['name'])
                else:
                    array_type = ElementaryType(
                        type_name['attributes']['name'])
            elif type_name[caller_context.get_key()] == 'UserDefinedTypeName':
                if is_compact_ast:
                    array_type = parse_type(UnknownType(type_name['name']),
                                            caller_context)
                else:
                    array_type = parse_type(
                        UnknownType(type_name['attributes']['name']),
                        caller_context)
            else:
                logger.error('Incorrect type array {}'.format(type_name))
                exit(-1)
            array = NewArray(depth, array_type)
            return array

        if type_name[caller_context.get_key()] == 'ElementaryTypeName':
            if is_compact_ast:
                elem_type = ElementaryType(type_name['name'])
            else:
                elem_type = ElementaryType(type_name['attributes']['name'])
            new_elem = NewElementaryType(elem_type)
            return new_elem

        assert type_name[caller_context.get_key()] == 'UserDefinedTypeName'

        if is_compact_ast:
            contract_name = type_name['name']
        else:
            contract_name = type_name['attributes']['name']
        new = NewContract(contract_name)
        return new

    elif name == 'ModifierInvocation':

        if is_compact_ast:
            called = parse_expression(expression['modifierName'],
                                      caller_context)
            arguments = []
            if expression['arguments']:
                arguments = [
                    parse_expression(a, caller_context)
                    for a in expression['arguments']
                ]
        else:
            children = expression['children']
            called = parse_expression(children[0], caller_context)
            arguments = [
                parse_expression(a, caller_context) for a in children[1::]
            ]

        call = CallExpression(called, arguments, 'Modifier')
        return call

    logger.error('Expression not parsed %s' % name)
    exit(-1)
Beispiel #4
0
def parse_call(expression, caller_context):
    src = expression['src']
    if caller_context.is_compact_ast:
        attributes = expression
        type_conversion = expression['kind'] == 'typeConversion'
        type_return = attributes['typeDescriptions']['typeString']

    else:
        attributes = expression['attributes']
        type_conversion = attributes['type_conversion']
        type_return = attributes['type']

    if type_conversion:
        type_call = parse_type(UnknownType(type_return), caller_context)

        if caller_context.is_compact_ast:
            assert len(expression['arguments']) == 1
            expression_to_parse = expression['arguments'][0]
        else:
            children = expression['children']
            assert len(children) == 2
            type_info = children[0]
            expression_to_parse = children[1]
            assert type_info['name'] in [
                'ElementaryTypenameExpression', 'ElementaryTypeNameExpression',
                'Identifier', 'TupleExpression', 'IndexAccess', 'MemberAccess'
            ]

        expression = parse_expression(expression_to_parse, caller_context)
        t = TypeConversion(expression, type_call)
        t.set_offset(src, caller_context.slither)
        return t

    call_gas = None
    call_value = None
    call_salt = None
    if caller_context.is_compact_ast:
        called = parse_expression(expression['expression'], caller_context)
        # If the next expression is a FunctionCallOptions
        # We can here the gas/value information
        # This is only available if the syntax is {gas: , value: }
        # For the .gas().value(), the member are considered as function call
        # And converted later to the correct info (convert.py)
        if expression['expression'][
                caller_context.get_key()] == 'FunctionCallOptions':
            call_with_options = expression['expression']
            for idx, name in enumerate(call_with_options.get('names', [])):
                option = parse_expression(call_with_options['options'][idx],
                                          caller_context)
                if name == 'value':
                    call_value = option
                if name == 'gas':
                    call_gas = option
                if name == 'salt':
                    call_salt = option
        arguments = []
        if expression['arguments']:
            arguments = [
                parse_expression(a, caller_context)
                for a in expression['arguments']
            ]
    else:
        children = expression['children']
        called = parse_expression(children[0], caller_context)
        arguments = [
            parse_expression(a, caller_context) for a in children[1::]
        ]

    if isinstance(called, SuperCallExpression):
        sp = SuperCallExpression(called, arguments, type_return)
        sp.set_offset(expression['src'], caller_context.slither)
        return sp
    call_expression = CallExpression(called, arguments, type_return)
    call_expression.set_offset(src, caller_context.slither)

    # Only available if the syntax {gas:, value:} was used
    call_expression.call_gas = call_gas
    call_expression.call_value = call_value
    call_expression.call_salt = call_salt
    return call_expression
def parse_expression(expression: Dict, caller_context: CallerContext) -> "Expression":
    # pylint: disable=too-many-nested-blocks,too-many-statements
    """

    Returns:
        str: expression
    """
    #  Expression
    #    = Expression ('++' | '--')
    #    | NewExpression
    #    | IndexAccess
    #    | MemberAccess
    #    | FunctionCall
    #    | '(' Expression ')'
    #    | ('!' | '~' | 'delete' | '++' | '--' | '+' | '-') Expression
    #    | Expression '**' Expression
    #    | Expression ('*' | '/' | '%') Expression
    #    | Expression ('+' | '-') Expression
    #    | Expression ('<<' | '>>') Expression
    #    | Expression '&' Expression
    #    | Expression '^' Expression
    #    | Expression '|' Expression
    #    | Expression ('<' | '>' | '<=' | '>=') Expression
    #    | Expression ('==' | '!=') Expression
    #    | Expression '&&' Expression
    #    | Expression '||' Expression
    #    | Expression '?' Expression ':' Expression
    #    | Expression ('=' | '|=' | '^=' | '&=' | '<<=' | '>>=' | '+=' | '-=' | '*=' | '/=' | '%=') Expression
    #    | PrimaryExpression
    # The AST naming does not follow the spec
    name = expression[caller_context.get_key()]
    is_compact_ast = caller_context.is_compact_ast
    src = expression["src"]

    if name == "UnaryOperation":
        if is_compact_ast:
            attributes = expression
        else:
            attributes = expression["attributes"]
        assert "prefix" in attributes
        operation_type = UnaryOperationType.get_type(attributes["operator"], attributes["prefix"])

        if is_compact_ast:
            expression = parse_expression(expression["subExpression"], caller_context)
        else:
            assert len(expression["children"]) == 1
            expression = parse_expression(expression["children"][0], caller_context)
        unary_op = UnaryOperation(expression, operation_type)
        unary_op.set_offset(src, caller_context.slither)
        return unary_op

    if name == "BinaryOperation":
        if is_compact_ast:
            attributes = expression
        else:
            attributes = expression["attributes"]
        operation_type = BinaryOperationType.get_type(attributes["operator"])

        if is_compact_ast:
            left_expression = parse_expression(expression["leftExpression"], caller_context)
            right_expression = parse_expression(expression["rightExpression"], caller_context)
        else:
            assert len(expression["children"]) == 2
            left_expression = parse_expression(expression["children"][0], caller_context)
            right_expression = parse_expression(expression["children"][1], caller_context)
        binary_op = BinaryOperation(left_expression, right_expression, operation_type)
        binary_op.set_offset(src, caller_context.slither)
        return binary_op

    if name in "FunctionCall":
        return parse_call(expression, caller_context)

    if name == "FunctionCallOptions":
        # call/gas info are handled in parse_call
        if is_compact_ast:
            called = parse_expression(expression["expression"], caller_context)
        else:
            called = parse_expression(expression["children"][0], caller_context)
        assert isinstance(called, (MemberAccess, NewContract, Identifier, TupleExpression))
        return called

    if name == "TupleExpression":
        #     For expression like
        #     (a,,c) = (1,2,3)
        #     the AST provides only two children in the left side
        #     We check the type provided (tuple(uint256,,uint256))
        #     To determine that there is an empty variable
        #     Otherwhise we would not be able to determine that
        #     a = 1, c = 3, and 2 is lost
        #
        #     Note: this is only possible with Solidity >= 0.4.12
        if is_compact_ast:
            expressions = [
                parse_expression(e, caller_context) if e else None for e in expression["components"]
            ]
        else:
            if "children" not in expression:
                attributes = expression["attributes"]
                components = attributes["components"]
                expressions = [
                    parse_expression(c, caller_context) if c else None for c in components
                ]
            else:
                expressions = [parse_expression(e, caller_context) for e in expression["children"]]
        # Add none for empty tuple items
        if "attributes" in expression:
            if "type" in expression["attributes"]:
                t = expression["attributes"]["type"]
                if ",," in t or "(," in t or ",)" in t:
                    t = t[len("tuple(") : -1]
                    elems = t.split(",")
                    for idx, _ in enumerate(elems):
                        if elems[idx] == "":
                            expressions.insert(idx, None)
        t = TupleExpression(expressions)
        t.set_offset(src, caller_context.slither)
        return t

    if name == "Conditional":
        if is_compact_ast:
            if_expression = parse_expression(expression["condition"], caller_context)
            then_expression = parse_expression(expression["trueExpression"], caller_context)
            else_expression = parse_expression(expression["falseExpression"], caller_context)
        else:
            children = expression["children"]
            assert len(children) == 3
            if_expression = parse_expression(children[0], caller_context)
            then_expression = parse_expression(children[1], caller_context)
            else_expression = parse_expression(children[2], caller_context)
        conditional = ConditionalExpression(if_expression, then_expression, else_expression)
        conditional.set_offset(src, caller_context.slither)
        return conditional

    if name == "Assignment":
        if is_compact_ast:
            left_expression = parse_expression(expression["leftHandSide"], caller_context)
            right_expression = parse_expression(expression["rightHandSide"], caller_context)

            operation_type = AssignmentOperationType.get_type(expression["operator"])

            operation_return_type = expression["typeDescriptions"]["typeString"]
        else:
            attributes = expression["attributes"]
            children = expression["children"]
            assert len(expression["children"]) == 2
            left_expression = parse_expression(children[0], caller_context)
            right_expression = parse_expression(children[1], caller_context)

            operation_type = AssignmentOperationType.get_type(attributes["operator"])
            operation_return_type = attributes["type"]

        assignement = AssignmentOperation(
            left_expression, right_expression, operation_type, operation_return_type
        )
        assignement.set_offset(src, caller_context.slither)
        return assignement

    if name == "Literal":

        subdenomination = None

        assert "children" not in expression

        if is_compact_ast:
            value = expression["value"]
            if value:
                if "subdenomination" in expression and expression["subdenomination"]:
                    subdenomination = expression["subdenomination"]
            elif not value and value != "":
                value = "0x" + expression["hexValue"]
            type_candidate = expression["typeDescriptions"]["typeString"]

            # Length declaration for array was None until solc 0.5.5
            if type_candidate is None:
                if expression["kind"] == "number":
                    type_candidate = "int_const"
        else:
            value = expression["attributes"]["value"]
            if value:
                if (
                    "subdenomination" in expression["attributes"]
                    and expression["attributes"]["subdenomination"]
                ):
                    subdenomination = expression["attributes"]["subdenomination"]
            elif value is None:
                # for literal declared as hex
                # see https://solidity.readthedocs.io/en/v0.4.25/types.html?highlight=hex#hexadecimal-literals
                assert "hexvalue" in expression["attributes"]
                value = "0x" + expression["attributes"]["hexvalue"]
            type_candidate = expression["attributes"]["type"]

        if type_candidate is None:
            if value.isdecimal():
                type_candidate = ElementaryType("uint256")
            else:
                type_candidate = ElementaryType("string")
        elif type_candidate.startswith("int_const "):
            type_candidate = ElementaryType("uint256")
        elif type_candidate.startswith("bool"):
            type_candidate = ElementaryType("bool")
        elif type_candidate.startswith("address"):
            type_candidate = ElementaryType("address")
        else:
            type_candidate = ElementaryType("string")
        literal = Literal(value, type_candidate, subdenomination)
        literal.set_offset(src, caller_context.slither)
        return literal

    if name == "Identifier":
        assert "children" not in expression

        t = None

        if caller_context.is_compact_ast:
            value = expression["name"]
            t = expression["typeDescriptions"]["typeString"]
        else:
            value = expression["attributes"]["value"]
            if "type" in expression["attributes"]:
                t = expression["attributes"]["type"]

        if t:
            found = re.findall("[struct|enum|function|modifier] \(([\[\] ()a-zA-Z0-9\.,_]*)\)", t)
            assert len(found) <= 1
            if found:
                value = value + "(" + found[0] + ")"
                value = filter_name(value)

        if "referencedDeclaration" in expression:
            referenced_declaration = expression["referencedDeclaration"]
        else:
            referenced_declaration = None

        var = find_variable(value, caller_context, referenced_declaration)

        identifier = Identifier(var)
        identifier.set_offset(src, caller_context.slither)
        return identifier

    if name == "IndexAccess":
        if is_compact_ast:
            index_type = expression["typeDescriptions"]["typeString"]
            left = expression["baseExpression"]
            right = expression.get("indexExpression", None)
        else:
            index_type = expression["attributes"]["type"]
            children = expression["children"]
            left = children[0]
            right = children[1] if len(children) > 1 else None
        # IndexAccess is used to describe ElementaryTypeNameExpression
        # if abi.decode is used
        # For example, abi.decode(data, ...(uint[]) )
        if right is None:
            ret = parse_expression(left, caller_context)
            # Nested array are not yet available in abi.decode
            if isinstance(ret, ElementaryTypeNameExpression):
                old_type = ret.type
                ret.type = ArrayType(old_type, None)
            return ret

        left_expression = parse_expression(left, caller_context)
        right_expression = parse_expression(right, caller_context)
        index = IndexAccess(left_expression, right_expression, index_type)
        index.set_offset(src, caller_context.slither)
        return index

    if name == "MemberAccess":
        if caller_context.is_compact_ast:
            member_name = expression["memberName"]
            member_type = expression["typeDescriptions"]["typeString"]
            # member_type = parse_type(
            #     UnknownType(expression["typeDescriptions"]["typeString"]), caller_context
            # )
            member_expression = parse_expression(expression["expression"], caller_context)
        else:
            member_name = expression["attributes"]["member_name"]
            member_type = expression["attributes"]["type"]
            # member_type = parse_type(UnknownType(expression["attributes"]["type"]), caller_context)
            children = expression["children"]
            assert len(children) == 1
            member_expression = parse_expression(children[0], caller_context)
        if str(member_expression) == "super":
            super_name = parse_super_name(expression, is_compact_ast)
            var = find_variable(super_name, caller_context, is_super=True)
            if var is None:
                raise VariableNotFound("Variable not found: {}".format(super_name))
            sup = SuperIdentifier(var)
            sup.set_offset(src, caller_context.slither)
            return sup
        member_access = MemberAccess(member_name, member_type, member_expression)
        member_access.set_offset(src, caller_context.slither)
        if str(member_access) in SOLIDITY_VARIABLES_COMPOSED:
            id_idx = Identifier(SolidityVariableComposed(str(member_access)))
            id_idx.set_offset(src, caller_context.slither)
            return id_idx
        return member_access

    if name == "ElementaryTypeNameExpression":
        return _parse_elementary_type_name_expression(expression, is_compact_ast, caller_context)

    # NewExpression is not a root expression, it's always the child of another expression
    if name == "NewExpression":

        if is_compact_ast:
            type_name = expression["typeName"]
        else:
            children = expression["children"]
            assert len(children) == 1
            type_name = children[0]

        if type_name[caller_context.get_key()] == "ArrayTypeName":
            depth = 0
            while type_name[caller_context.get_key()] == "ArrayTypeName":
                # Note: dont conserve the size of the array if provided
                # We compute it directly
                if is_compact_ast:
                    type_name = type_name["baseType"]
                else:
                    type_name = type_name["children"][0]
                depth += 1
            if type_name[caller_context.get_key()] == "ElementaryTypeName":
                if is_compact_ast:
                    array_type = ElementaryType(type_name["name"])
                else:
                    array_type = ElementaryType(type_name["attributes"]["name"])
            elif type_name[caller_context.get_key()] == "UserDefinedTypeName":
                if is_compact_ast:
                    array_type = parse_type(UnknownType(type_name["name"]), caller_context)
                else:
                    array_type = parse_type(
                        UnknownType(type_name["attributes"]["name"]), caller_context
                    )
            elif type_name[caller_context.get_key()] == "FunctionTypeName":
                array_type = parse_type(type_name, caller_context)
            else:
                raise ParsingError("Incorrect type array {}".format(type_name))
            array = NewArray(depth, array_type)
            array.set_offset(src, caller_context.slither)
            return array

        if type_name[caller_context.get_key()] == "ElementaryTypeName":
            if is_compact_ast:
                elem_type = ElementaryType(type_name["name"])
            else:
                elem_type = ElementaryType(type_name["attributes"]["name"])
            new_elem = NewElementaryType(elem_type)
            new_elem.set_offset(src, caller_context.slither)
            return new_elem

        assert type_name[caller_context.get_key()] == "UserDefinedTypeName"

        if is_compact_ast:

            # Changed introduced in Solidity 0.8
            # see https://github.com/crytic/slither/issues/794

            # TODO explore more the changes introduced in 0.8 and the usage of pathNode/IdentifierPath
            if "name" not in type_name:
                assert "pathNode" in type_name and "name" in type_name["pathNode"]
                contract_name = type_name["pathNode"]["name"]
            else:
                contract_name = type_name["name"]
        else:
            contract_name = type_name["attributes"]["name"]
        new = NewContract(contract_name)
        new.set_offset(src, caller_context.slither)
        return new

    if name == "ModifierInvocation":

        if is_compact_ast:
            called = parse_expression(expression["modifierName"], caller_context)
            arguments = []
            if expression.get("arguments", None):
                arguments = [parse_expression(a, caller_context) for a in expression["arguments"]]
        else:
            children = expression["children"]
            called = parse_expression(children[0], caller_context)
            arguments = [parse_expression(a, caller_context) for a in children[1::]]

        call = CallExpression(called, arguments, "Modifier")
        call.set_offset(src, caller_context.slither)
        return call

    if name == "IndexRangeAccess":
        # For now, we convert array slices to a direct array access
        # As a result the generated IR will lose the slices information
        # As far as I understand, array slice are only used in abi.decode
        # https://solidity.readthedocs.io/en/v0.6.12/types.html
        # TODO: Investigate array slices usage and implication for the IR
        base = parse_expression(expression["baseExpression"], caller_context)
        return base

    # Introduced with solc 0.8
    if name == "IdentifierPath":

        if caller_context.is_compact_ast:
            value = expression["name"]

            if "referencedDeclaration" in expression:
                referenced_declaration = expression["referencedDeclaration"]
            else:
                referenced_declaration = None

            var = find_variable(value, caller_context, referenced_declaration)

            identifier = Identifier(var)
            identifier.set_offset(src, caller_context.slither)
            return identifier

        raise ParsingError("IdentifierPath not currently supported for the legacy ast")

    raise ParsingError("Expression not parsed %s" % name)
def parse_call(expression: Dict, caller_context):  # pylint: disable=too-many-statements
    src = expression["src"]
    if caller_context.is_compact_ast:
        attributes = expression
        type_conversion = expression["kind"] == "typeConversion"
        type_return = attributes["typeDescriptions"]["typeString"]

    else:
        attributes = expression["attributes"]
        type_conversion = attributes["type_conversion"]
        type_return = attributes["type"]

    if type_conversion:
        type_call = parse_type(UnknownType(type_return), caller_context)

        if caller_context.is_compact_ast:
            assert len(expression["arguments"]) == 1
            expression_to_parse = expression["arguments"][0]
        else:
            children = expression["children"]
            assert len(children) == 2
            type_info = children[0]
            expression_to_parse = children[1]
            assert type_info["name"] in [
                "ElementaryTypenameExpression",
                "ElementaryTypeNameExpression",
                "Identifier",
                "TupleExpression",
                "IndexAccess",
                "MemberAccess",
            ]

        expression = parse_expression(expression_to_parse, caller_context)
        t = TypeConversion(expression, type_call)
        t.set_offset(src, caller_context.slither)
        return t

    call_gas = None
    call_value = None
    call_salt = None
    if caller_context.is_compact_ast:
        called = parse_expression(expression["expression"], caller_context)
        # If the next expression is a FunctionCallOptions
        # We can here the gas/value information
        # This is only available if the syntax is {gas: , value: }
        # For the .gas().value(), the member are considered as function call
        # And converted later to the correct info (convert.py)
        if expression["expression"][caller_context.get_key()] == "FunctionCallOptions":
            call_with_options = expression["expression"]
            for idx, name in enumerate(call_with_options.get("names", [])):
                option = parse_expression(call_with_options["options"][idx], caller_context)
                if name == "value":
                    call_value = option
                if name == "gas":
                    call_gas = option
                if name == "salt":
                    call_salt = option
        arguments = []
        if expression["arguments"]:
            arguments = [parse_expression(a, caller_context) for a in expression["arguments"]]
    else:
        children = expression["children"]
        called = parse_expression(children[0], caller_context)
        arguments = [parse_expression(a, caller_context) for a in children[1::]]

    if isinstance(called, SuperCallExpression):
        sp = SuperCallExpression(called, arguments, type_return)
        sp.set_offset(expression["src"], caller_context.slither)
        return sp
    call_expression = CallExpression(called, arguments, type_return)
    call_expression.set_offset(src, caller_context.slither)

    # Only available if the syntax {gas:, value:} was used
    call_expression.call_gas = call_gas
    call_expression.call_value = call_value
    call_expression.call_salt = call_salt
    return call_expression
Beispiel #7
0
def parse_expression(expression, caller_context):
    """

    Returns:
        str: expression
    """
    #  Expression
    #    = Expression ('++' | '--')
    #    | NewExpression
    #    | IndexAccess
    #    | MemberAccess
    #    | FunctionCall
    #    | '(' Expression ')'
    #    | ('!' | '~' | 'delete' | '++' | '--' | '+' | '-') Expression
    #    | Expression '**' Expression
    #    | Expression ('*' | '/' | '%') Expression
    #    | Expression ('+' | '-') Expression
    #    | Expression ('<<' | '>>') Expression
    #    | Expression '&' Expression
    #    | Expression '^' Expression
    #    | Expression '|' Expression
    #    | Expression ('<' | '>' | '<=' | '>=') Expression
    #    | Expression ('==' | '!=') Expression
    #    | Expression '&&' Expression
    #    | Expression '||' Expression
    #    | Expression '?' Expression ':' Expression
    #    | Expression ('=' | '|=' | '^=' | '&=' | '<<=' | '>>=' | '+=' | '-=' | '*=' | '/=' | '%=') Expression
    #    | PrimaryExpression

    # The AST naming does not follow the spec
    name = expression['name']

    if name == 'UnaryOperation':
        attributes = expression['attributes']
        assert 'prefix' in attributes
        operation_type = UnaryOperationType.get_type(attributes['operator'],
                                                     attributes['prefix'])

        assert len(expression['children']) == 1
        expression = parse_expression(expression['children'][0],
                                      caller_context)
        unary_op = UnaryOperation(expression, operation_type)
        return unary_op

    elif name == 'BinaryOperation':
        attributes = expression['attributes']
        operation_type = BinaryOperationType.get_type(attributes['operator'])

        assert len(expression['children']) == 2
        left_expression = parse_expression(expression['children'][0],
                                           caller_context)
        right_expression = parse_expression(expression['children'][1],
                                            caller_context)
        binary_op = BinaryOperation(left_expression, right_expression,
                                    operation_type)
        return binary_op

    elif name == 'FunctionCall':
        return parse_call(expression, caller_context)

    elif name == 'TupleExpression':
        if 'children' not in expression:
            attributes = expression['attributes']
            components = attributes['components']
            expressions = [
                parse_expression(c, caller_context) if c else None
                for c in components
            ]
        else:
            expressions = [
                parse_expression(e, caller_context)
                for e in expression['children']
            ]
        t = TupleExpression(expressions)
        return t

    elif name == 'Conditional':
        children = expression['children']
        assert len(children) == 3
        if_expression = parse_expression(children[0], caller_context)
        then_expression = parse_expression(children[1], caller_context)
        else_expression = parse_expression(children[2], caller_context)
        conditional = ConditionalExpression(if_expression, then_expression,
                                            else_expression)
        #print(conditional)
        return conditional

    elif name == 'Assignment':
        attributes = expression['attributes']
        children = expression['children']
        assert len(expression['children']) == 2

        left_expression = parse_expression(children[0], caller_context)
        right_expression = parse_expression(children[1], caller_context)
        operation_type = AssignmentOperationType.get_type(
            attributes['operator'])
        operation_return_type = attributes['type']

        assignement = AssignmentOperation(left_expression, right_expression,
                                          operation_type,
                                          operation_return_type)
        return assignement

    elif name == 'Literal':
        assert 'children' not in expression
        value = expression['attributes']['value']
        literal = Literal(value)
        return literal

    elif name == 'Identifier':
        assert 'children' not in expression
        value = expression['attributes']['value']
        if 'type' in expression['attributes']:
            t = expression['attributes']['type']
            if t:
                found = re.findall(
                    '[struct|enum|function|modifier] \(([\[\] ()a-zA-Z0-9\.,_]*)\)',
                    t)
                assert len(found) <= 1
                if found:
                    value = value + '(' + found[0] + ')'
                    value = filter_name(value)

        var = find_variable(value, caller_context)

        identifier = Identifier(var)
        return identifier

    elif name == 'IndexAccess':
        index_type = expression['attributes']['type']
        children = expression['children']
        assert len(children) == 2
        left_expression = parse_expression(children[0], caller_context)
        right_expression = parse_expression(children[1], caller_context)
        index = IndexAccess(left_expression, right_expression, index_type)
        return index

    elif name == 'MemberAccess':
        member_name = expression['attributes']['member_name']
        member_type = expression['attributes']['type']
        children = expression['children']
        assert len(children) == 1
        member_expression = parse_expression(children[0], caller_context)
        if str(member_expression) == 'super':
            super_name = parse_super_name(expression)
            if isinstance(caller_context, Contract):
                inheritance = caller_context.inheritance
            else:
                assert isinstance(caller_context, Function)
                inheritance = caller_context.contract.inheritance
            var = None
            for father in inheritance:
                try:
                    var = find_variable(super_name, father)
                    break
                except VariableNotFound:
                    continue
            if var is None:
                raise VariableNotFound(
                    'Variable not found: {}'.format(super_name))
            return SuperIdentifier(var)
        member_access = MemberAccess(member_name, member_type,
                                     member_expression)
        if str(member_access) in SOLIDITY_VARIABLES_COMPOSED:
            return Identifier(SolidityVariableComposed(str(member_access)))
        return member_access

    elif name == 'ElementaryTypeNameExpression':
        # nop exression
        # uint;
        assert 'children' not in expression
        value = expression['attributes']['value']
        t = parse_type(UnknownType(value), caller_context)

        return ElementaryTypeNameExpression(t)

    # NewExpression is not a root expression, it's always the child of another expression
    elif name == 'NewExpression':
        new_type = expression['attributes']['type']

        children = expression['children']
        assert len(children) == 1
        #new_expression = parse_expression(children[0])

        child = children[0]

        if child['name'] == 'ArrayTypeName':
            depth = 0
            while child['name'] == 'ArrayTypeName':
                # Note: dont conserve the size of the array if provided
                #assert len(child['children']) == 1
                child = child['children'][0]
                depth += 1

            if child['name'] == 'ElementaryTypeName':
                array_type = ElementaryType(child['attributes']['name'])
            elif child['name'] == 'UserDefinedTypeName':
                array_type = parse_type(
                    UnknownType(child['attributes']['name']), caller_context)
            else:
                logger.error('Incorrect type array {}'.format(child))
                exit(-1)
            array = NewArray(depth, array_type)
            return array

        if child['name'] == 'ElementaryTypeName':
            elem_type = ElementaryType(child['attributes']['name'])
            new_elem = NewElementaryType(elem_type)
            return new_elem

        assert child['name'] == 'UserDefinedTypeName'

        contract_name = child['attributes']['name']
        new = NewContract(contract_name)
        return new

    elif name == 'ModifierInvocation':

        children = expression['children']
        called = parse_expression(children[0], caller_context)
        arguments = [
            parse_expression(a, caller_context) for a in children[1::]
        ]

        call = CallExpression(called, arguments, 'Modifier')
        return call

    logger.error('Expression not parsed %s' % name)
    exit(-1)