test_api.py

# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.

import datetime
import enum
import re
import sys
import typing
from typing import Annotated

import pytest

from cryptography.hazmat import asn1


class TestTypesAPI:
    def test_repr_printable_string(self) -> None:
        my_string = "MyString"
        assert (
            repr(asn1.PrintableString(my_string))
            == f"PrintableString({my_string!r})"
        )

    def test_printable_string_as_str(self) -> None:
        my_string = "MyString"
        assert asn1.PrintableString(my_string).as_str() == my_string

    def test_invalid_printable_string(self) -> None:
        with pytest.raises(ValueError, match="invalid PrintableString: café"):
            asn1.PrintableString("café")

    def test_repr_ia5_string(self) -> None:
        my_string = "MyString"
        assert repr(asn1.IA5String(my_string)) == f"IA5String({my_string!r})"

    def test_ia5_string_as_str(self) -> None:
        my_string = "MyString"
        assert asn1.IA5String(my_string).as_str() == my_string

    def test_invalid_ia5_string(self) -> None:
        with pytest.raises(ValueError, match="invalid IA5String: café"):
            asn1.IA5String("café")

    def test_utc_time_as_datetime(self) -> None:
        dt = datetime.datetime(
            2000, 1, 1, 10, 10, 10, tzinfo=datetime.timezone.utc
        )
        assert asn1.UTCTime(dt).as_datetime() == dt

    def test_repr_utc_time(self) -> None:
        dt = datetime.datetime(
            2000, 1, 1, 10, 10, 10, tzinfo=datetime.timezone.utc
        )
        assert repr(asn1.UTCTime(dt)) == f"UTCTime({dt!r})"

    def test_invalid_utc_time(self) -> None:
        with pytest.raises(
            ValueError,
            match="cannot initialize with naive datetime object",
        ):
            # We don't allow naive datetime objects
            asn1.UTCTime(datetime.datetime(2000, 1, 1, 10, 10, 10))

        with pytest.raises(ValueError, match="invalid UTCTime"):
            # UTCTime does not support dates before 1950
            asn1.UTCTime(
                datetime.datetime(
                    1940, 1, 1, 10, 10, 10, tzinfo=datetime.timezone.utc
                )
            )

        with pytest.raises(ValueError, match="invalid UTCTime"):
            # UTCTime does not support dates after 2050
            asn1.UTCTime(
                datetime.datetime(
                    2090, 1, 1, 10, 10, 10, tzinfo=datetime.timezone.utc
                )
            )

        with pytest.raises(
            ValueError,
            match="invalid UTCTime: fractional seconds are not supported",
        ):
            # UTCTime does not support fractional seconds
            asn1.UTCTime(
                datetime.datetime(
                    2020,
                    1,
                    1,
                    10,
                    10,
                    10,
                    500000,
                    tzinfo=datetime.timezone.utc,
                )
            )

    def test_generalized_time_as_datetime(self) -> None:
        dt = datetime.datetime(
            2000, 1, 1, 10, 10, 10, 300000, tzinfo=datetime.timezone.utc
        )
        assert asn1.GeneralizedTime(dt).as_datetime() == dt

    def test_repr_generalized_time(self) -> None:
        dt = datetime.datetime(
            2000, 1, 1, 10, 10, 10, 300000, tzinfo=datetime.timezone.utc
        )
        assert repr(asn1.GeneralizedTime(dt)) == f"GeneralizedTime({dt!r})"

    def test_invalid_generalized_time(self) -> None:
        with pytest.raises(
            ValueError,
            match="cannot initialize with naive datetime object",
        ):
            # We don't allow naive datetime objects
            asn1.GeneralizedTime(datetime.datetime(2000, 1, 1, 10, 10, 10))

    def test_bitstring_getters(self) -> None:
        data = b"\x01\x02\x30"
        bt = asn1.BitString(data=data, padding_bits=2)

        assert bt.as_bytes() == data
        assert bt.padding_bits() == 2

    def test_repr_bitstring(self) -> None:
        data = b"\x01\x02\x30"
        assert (
            repr(asn1.BitString(data, 2))
            == f"BitString(data={data!r}, padding_bits=2)"
        )

    def test_invalid_bitstring(self) -> None:
        with pytest.raises(
            ValueError,
            match="invalid BIT STRING",
        ):
            # Padding bits cannot be > 7
            asn1.BitString(data=b"\x01\x02\x03", padding_bits=8)

        with pytest.raises(
            ValueError,
            match="invalid BIT STRING",
        ):
            # Padding bits have to be zero
            asn1.BitString(data=b"\x01\x02\x03", padding_bits=2)

    def test_setof_as_list(self) -> None:
        my_list = [1, 2, 3]
        assert asn1.SetOf(my_list).as_list() == my_list

    def test_repr_setof(self) -> None:
        assert repr(asn1.SetOf([1, 2, 3])) == "SetOf([1, 2, 3])"

    def test_repr_null(self) -> None:
        assert repr(asn1.Null()) == "Null()"


class TestSequenceAPI:
    def test_fail_unsupported_field(self) -> None:
        # Not a sequence
        class Unsupported:
            foo: int

        with pytest.raises(TypeError, match="cannot handle type"):

            @asn1.sequence
            class Example:
                foo: Unsupported

    def test_fail_init_incorrect_field_name(self) -> None:
        @asn1.sequence
        class Example:
            foo: int

        with pytest.raises(
            TypeError, match="got an unexpected keyword argument 'bar'"
        ):
            Example(bar=3)  # type: ignore[call-arg]

    def test_fail_init_missing_field_name(self) -> None:
        @asn1.sequence
        class Example:
            foo: int

        expected_err = (
            "missing 1 required keyword-only argument: 'foo'"
            if sys.version_info >= (3, 10)
            else "missing 1 required positional argument: 'foo'"
        )

        with pytest.raises(TypeError, match=expected_err):
            Example()  # type: ignore[call-arg]

    def test_fail_positional_field_initialization(self) -> None:
        @asn1.sequence
        class Example:
            foo: int

        # The kw-only init is only enforced in Python >= 3.10, which is
        # when the parameter `kw_only` for `dataclasses.datalass` was
        # added.
        if sys.version_info < (3, 10):
            assert Example(5).foo == 5  # type: ignore[misc]
        else:
            with pytest.raises(
                TypeError,
                match="takes 1 positional argument but 2 were given",
            ):
                Example(5)  # type: ignore[misc]

    def test_fail_malformed_root_type(self) -> None:
        @asn1.sequence
        class Invalid:
            foo: int

        setattr(Invalid, "__asn1_root__", int)

        with pytest.raises(TypeError, match="unsupported root type"):

            @asn1.sequence
            class Example:
                foo: Invalid

    def test_fail_unsupported_annotation(self) -> None:
        with pytest.raises(
            TypeError, match="unsupported annotation: some annotation"
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[int, "some annotation"]

    def test_fail_unsupported_size_annotation(self) -> None:
        with pytest.raises(
            TypeError,
            match="field 'invalid' has a SIZE annotation, but SIZE "
            "annotations are only supported for fields of types: ",
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[int, asn1.Size(min=0, max=3)]

    def test_fail_multiple_default_annotations(self) -> None:
        with pytest.raises(
            TypeError,
            match="multiple DEFAULT annotations found in field 'invalid'",
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[
                    int, asn1.Default(value=8), asn1.Default(value=9)
                ]

    def test_fail_multiple_implicit_annotations(self) -> None:
        with pytest.raises(
            TypeError,
            match="multiple IMPLICIT/EXPLICIT annotations found in field "
            "'invalid'",
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[int, asn1.Implicit(0), asn1.Implicit(1)]

    def test_fail_multiple_explicit_annotations(self) -> None:
        with pytest.raises(
            TypeError,
            match="multiple IMPLICIT/EXPLICIT annotations found in field "
            "'invalid'",
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[int, asn1.Explicit(0), asn1.Explicit(1)]

    def test_fail_multiple_size_annotations(self) -> None:
        with pytest.raises(
            TypeError,
            match="multiple SIZE annotations found in field 'invalid'",
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[
                    int, asn1.Size(min=1, max=2), asn1.Size(min=1, max=2)
                ]

    def test_fail_optional_with_default_field(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "optional (`X | None`) types should not have a "
                "DEFAULT annotation"
            ),
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[
                    typing.Union[int, None], asn1.Default(value=9)
                ]

    def test_fail_optional_with_annotations_inside(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "optional (`X | None`) types cannot have `X` "
                "annotated: annotations must apply to the union (i.e: "
                "`Annotated[X | None, annotation]`)"
            ),
        ):

            @asn1.sequence
            class Example2:
                invalid: typing.Union[
                    Annotated[int, asn1.Default(value=9)], None
                ]

    def test_fail_choice_with_inconsistent_types(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "When using `asn1.Variant` in a union, all the other "
                "types in the union must also be `asn1.Variant`"
            ),
        ):

            @asn1.sequence
            class Example2:
                invalid: typing.Union[
                    int, asn1.Variant[bool, typing.Literal["myTag"]]
                ]

    def test_fail_choice_with_duplicate_tags(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "When using `asn1.Variant` in a union, the tags used "
                "must be unique"
            ),
        ):

            @asn1.sequence
            class Example2:
                invalid: typing.Union[
                    asn1.Variant[int, typing.Literal["myTag"]],
                    asn1.Variant[bool, typing.Literal["myTag"]],
                ]

    def test_fields_of_variant_type(self) -> None:
        from cryptography.hazmat.bindings._rust import declarative_asn1

        # Needed for coverage of the `_0`, `_1`, etc fields generated
        # for tuple enum variants
        seq = declarative_asn1.Type.Sequence(type(None), {})
        assert seq._0 is type(None)
        assert seq._1 == {}

        set = declarative_asn1.Type.Set(type(None), {})
        assert set._0 is type(None)
        assert set._1 == {}

        ann_type = declarative_asn1.AnnotatedType(
            seq, declarative_asn1.Annotation()
        )
        opt = declarative_asn1.Type.Option(ann_type)
        assert opt._0 == ann_type

        seq_of = declarative_asn1.Type.SequenceOf(ann_type)
        assert seq_of._0 is ann_type

        set_of = declarative_asn1.Type.SetOf(ann_type)
        assert set_of._0 is ann_type

        my_list: list[int] = list()
        choice = declarative_asn1.Type.Choice(my_list)
        assert choice._0 is my_list

        value_set = declarative_asn1.Type.ValueSet(type(None), ann_type)
        assert value_set._0 is type(None)
        assert value_set._1 is ann_type

    def test_fields_of_variant_encoding(self) -> None:
        from cryptography.hazmat.bindings._rust import declarative_asn1

        # Needed for coverage of the `_0`, `_1`, etc fields generated
        # for tuple enum variants
        implicit = declarative_asn1.Encoding.Implicit(0)
        explicit = declarative_asn1.Encoding.Explicit(0)
        assert implicit._0 == 0
        assert explicit._0 == 0

    def test_fail_choice_with_implicit_encoding(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "CHOICE (`X | Y | ...`) types should not have an IMPLICIT "
                "annotation"
            ),
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[typing.Union[int, bool], asn1.Implicit(0)]

    def test_fail_choice_with_non_literal_tag(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "When using `asn1.Variant` in a type annotation, the second "
                "type parameter must be a `typing.Literal` type. E.g: "
                '`Variant[int, typing.Literal["MyInt"]]`.'
            ),
        ):

            @asn1.sequence
            class Example:
                foo: typing.Union[
                    Annotated[
                        asn1.Variant[int, str],
                        asn1.Implicit(0),
                    ],
                    Annotated[
                        asn1.Variant[int, typing.Literal["IntB"]],
                        asn1.Implicit(1),
                    ],
                ]

    def test_fail_tlv_with_implicit_encoding(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "field 'invalid' has an IMPLICIT annotation, but IMPLICIT "
                "annotations are not supported for TLV types."
            ),
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[asn1.TLV, asn1.Implicit(0)]

    def test_fail_tlv_with_default_encoding(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "field 'invalid' has a DEFAULT annotation, but DEFAULT "
                "annotations are not supported for TLV types."
            ),
        ):

            @asn1.sequence
            class Example:
                invalid: Annotated[asn1.TLV, asn1.Default(value=9)]

    def test_fail_optional_tlv(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "optional TLV types (`TLV | None`) are not currently supported"
            ),
        ):

            @asn1.sequence
            class Example:
                invalid: typing.Union[asn1.TLV, None]


class TestSetAPI:
    def test_fail_unsupported_field(self) -> None:
        class Unsupported:
            foo: int

        with pytest.raises(TypeError, match="cannot handle type"):

            @asn1.set
            class Example:
                foo: Unsupported

    def test_fail_init_incorrect_field_name(self) -> None:
        @asn1.set
        class Example:
            foo: int

        with pytest.raises(
            TypeError, match="got an unexpected keyword argument 'bar'"
        ):
            Example(bar=3)  # type: ignore[call-arg]

    def test_fail_init_missing_field_name(self) -> None:
        @asn1.set
        class Example:
            foo: int

        expected_err = (
            "missing 1 required keyword-only argument: 'foo'"
            if sys.version_info >= (3, 10)
            else "missing 1 required positional argument: 'foo'"
        )

        with pytest.raises(TypeError, match=expected_err):
            Example()  # type: ignore[call-arg]

    def test_fail_positional_field_initialization(self) -> None:
        @asn1.set
        class Example:
            foo: int

        # The kw-only init is only enforced in Python >= 3.10, which is
        # when the parameter `kw_only` for `dataclasses.datalass` was
        # added.
        if sys.version_info < (3, 10):
            assert Example(5).foo == 5  # type: ignore[misc]
        else:
            with pytest.raises(
                TypeError,
                match="takes 1 positional argument but 2 were given",
            ):
                Example(5)  # type: ignore[misc]

    def test_fail_malformed_root_type(self) -> None:
        @asn1.set
        class Invalid:
            foo: int

        setattr(Invalid, "__asn1_root__", int)

        with pytest.raises(TypeError, match="unsupported root type"):

            @asn1.set
            class Example:
                foo: Invalid


class TestValueSetAPI:
    def test_fail_non_enum(self) -> None:
        with pytest.raises(
            TypeError,
            match=re.escape(
                "value sets can only be defined from enum.Enum subclasses"
            ),
        ):

            @asn1.value_set(int)
            class Example:
                pass

    def test_fail_empty_enum(self) -> None:
        with pytest.raises(
            TypeError,
            match="value set 'Example' must have at least one member",
        ):

            @asn1.value_set(int)
            class Example(enum.Enum):
                pass

    def test_fail_member_value_of_wrong_type(self) -> None:
        with pytest.raises(
            TypeError,
            match="member 'B' of value set 'Example' must have a value "
            "of type 'int', got: 'str'",
        ):

            @asn1.value_set(int)
            class Example(enum.Enum):
                A = 1
                B = "b"

    def test_fail_unsupported_value_type(self) -> None:
        with pytest.raises(
            TypeError,
            match="cannot handle type",
        ):
            asn1.value_set(float)