Пример #1
0
def encode_dss_signature(r, s):
    return encode_der(
        SEQUENCE,
        encode_der(INTEGER, encode_der_integer(r)),
        encode_der(INTEGER, encode_der_integer(s)),
    )
Пример #2
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def test_der():
    # This input is the following structure, using
    # https://github.com/google/der-ascii
    #
    # SEQUENCE {
    #   SEQUENCE {
    #     NULL {}
    #     INTEGER { 42 }
    #     OCTET_STRING { "hello" }
    #   }
    # }
    der = b"\x30\x0e\x30\x0c\x05\x00\x02\x01\x2a\x04\x05\x68\x65\x6c\x6c\x6f"
    reader = DERReader(der)
    with pytest.raises(ValueError):
        reader.check_empty()

    with pytest.raises(ValueError):
        with reader:
            pass

    with pytest.raises(ZeroDivisionError):
        with DERReader(der):
            raise ZeroDivisionError

    # Parse the outer element.
    outer = reader.read_element(SEQUENCE)
    reader.check_empty()
    assert outer.data.tobytes() == der[2:]

    # Parse the outer element with read_any_element.
    reader = DERReader(der)
    tag, outer2 = reader.read_any_element()
    reader.check_empty()
    assert tag == SEQUENCE
    assert outer2.data.tobytes() == der[2:]

    # Parse the outer element with read_single_element.
    outer3 = DERReader(der).read_single_element(SEQUENCE)
    assert outer3.data.tobytes() == der[2:]

    # read_single_element rejects trailing data.
    with pytest.raises(ValueError):
        DERReader(der + der).read_single_element(SEQUENCE)

    # Continue parsing the structure.
    inner = outer.read_element(SEQUENCE)
    outer.check_empty()

    # Parsing a missing optional element should work.
    assert inner.read_optional_element(INTEGER) is None

    null = inner.read_element(NULL)
    null.check_empty()

    # Parsing a present optional element should work.
    integer = inner.read_optional_element(INTEGER)
    assert integer is not None
    assert integer.as_integer() == 42

    octet_string = inner.read_element(OCTET_STRING)
    assert octet_string.data.tobytes() == b"hello"

    # Parsing a missing optional element should work when the input is empty.
    inner.check_empty()
    assert inner.read_optional_element(INTEGER) is None

    # Re-encode the same structure.
    der2 = encode_der(
        SEQUENCE,
        encode_der(
            SEQUENCE,
            encode_der(NULL),
            encode_der(INTEGER, encode_der_integer(42)),
            encode_der(OCTET_STRING, b"hello"),
        ),
    )
    assert der2 == der
Пример #3
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def test_integer(value, der):
    assert encode_der_integer(value) == der
    assert DERReader(der).as_integer() == value
Пример #4
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def test_invalid_integer_encode():
    with pytest.raises(ValueError):
        encode_der_integer(-1)

    with pytest.raises(ValueError):
        encode_der_integer("not an integer")  # type: ignore[arg-type]
Пример #5
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def encode_dss_signature(r: int, s: int) -> bytes:
    return encode_der(
        SEQUENCE,
        encode_der(INTEGER, encode_der_integer(r)),
        encode_der(INTEGER, encode_der_integer(s)),
    )