path: root/tests/test_generator.py

# SPDX-License-Identifier: BSD-2-Clause
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# Copyright (c) 2020-2026, Simeon Simeonov
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"""Tests for otp2289.generator"""

import pytest

import otp2289


def test_caller_exceptions() -> None:
    """Tests the exceptions when calling an initialized object"""
    gen = otp2289.OTPGenerator(
        b'This is a test.', 'TeSt', otp2289.OTP_ALGO_MD5
    )
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        gen.generate_otp_response('3')  # ty: ignore[invalid-argument-type]
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'Step value MUST be an int'
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        gen.generate_otp_response(-1)
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'Step value MUST be >= 0'
    with pytest.raises(otp2289.OTPChallengeError) as exc_info:
        gen.generate_otp_response_from_challenge(
            b'md5 fbd TeSt'  # ty: ignore[invalid-argument-type]
        )
    assert exc_info.type is otp2289.OTPChallengeError
    assert exc_info.value.args[0] == 'Challenge must be str'
    with pytest.raises(otp2289.OTPChallengeError) as exc_info:
        gen.generate_otp_response_from_challenge('md5 fbd TeSt')
    assert exc_info.type is otp2289.OTPChallengeError
    assert exc_info.value.args[0] == 'Invalid challenge'
    with pytest.raises(otp2289.OTPChallengeError) as exc_info:
        gen.generate_otp_response_from_challenge('otp-md5 fbd TeSt')
    assert exc_info.type is otp2289.OTPChallengeError
    assert exc_info.value.args[0] == 'Invalid challenge'


def test_constructor_exceptions() -> None:
    """
    Tests the exceptions when initializing a new object (in the constructor)
    """
    # test the otp2289.OTPGenerator __init__ and validators
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(
            b'This is a test.',
            'TeStø'.encode(),  # ty: ignore[invalid-argument-type]
            otp2289.OTP_ALGO_MD5,
        )
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'Seed must be a string'
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(
            b'This is a test.', 'TeStøtEsTteSTteStTest', otp2289.OTP_ALGO_SHA1
        )
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == (
        'The seed MUST be of 1 to 16 characters in length'
    )
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(
            b'This is a test.', 'TeStø', otp2289.OTP_ALGO_SHA1
        )
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == (
        'The seed MUST consist of purely alphanumeric characters'
    )
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(b'This is a test.', 'TeSt', 9)
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == (
        'hash_algo is not among the known algorithms'
    )
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(
            b'This is a test.',
            'TeSt',
            b'md5',  # ty: ignore[invalid-argument-type]
        )
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'hash_algo must be an int or a str'
    # test the package structure as well
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(b'This is a test.', 'TeSt', 'foo')
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == (
        'foo is not supported by this version of the hashlib module'
    )
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(
            '1234567',  # ty: ignore[invalid-argument-type]
            'TeSt',
            otp2289.OTP_ALGO_MD5,
        )
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'Password must be a byte-string'
    with pytest.raises(otp2289.OTPGeneratorError) as exc_info:
        otp2289.OTPGenerator(b'1234567', 'TeSt', otp2289.OTP_ALGO_MD5)
    assert exc_info.type is otp2289.OTPGeneratorError
    assert exc_info.value.args[0] == 'Password must be longer than 10 bytes'


def test_md5() -> None:
    """
    Tests the MD5 functionality of the OTPGenerator as described in the RFC

    Those are the tests from 'RFC-2289 Appendix C - OTP Verification Examples'
    """
    # We could run this in a loop, but I guess "Readability counts."
    # pass='This is a test.', seed='TeSt'
    gen = otp2289.OTPGenerator(
        b'This is a test.', 'TeSt', otp2289.OTP_ALGO_MD5
    )
    response = gen.generate_otp_response(0)
    assert isinstance(response, otp2289.OTPResponse)
    assert isinstance(response.words, str)
    assert isinstance(response.hexdigest, str)
    assert response.hexdigest == '0x9e876134d90499dd'
    assert response.words == 'INCH SEA ANNE LONG AHEM TOUR'

    # step 1
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0x7965e05436f5029f'
    assert response.words == 'EASE OIL FUM CURE AWRY AVIS'
    assert (
        gen.generate_otp_response_from_challenge('otp-md5 1   TeSt').hexdigest
        == '0x7965e05436f5029f'
    )
    assert (
        gen.generate_otp_response_from_challenge('otp-md5 1 TeSt').words
        == 'EASE OIL FUM CURE AWRY AVIS'
    )

    # step 99
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0x50fe1962c4965880'
    assert response.words == 'BAIL TUFT BITS GANG CHEF THY'
    assert (
        gen.generate_otp_response_from_challenge('otp-md5 99   TeSt').hexdigest
        == '0x50fe1962c4965880'
    )
    assert (
        gen.generate_otp_response_from_challenge('otp-md5 99   TeSt').words
        == 'BAIL TUFT BITS GANG CHEF THY'
    )

    # iterator test
    hexdigests = list(gen.otp_response_range(105))  # testing the range itself
    words = list(gen.otp_response_range(99))
    hexdigests.reverse()
    words.reverse()
    assert hexdigests[0].hexdigest == '0x9e876134d90499dd'
    assert hexdigests[1].hexdigest == '0x7965e05436f5029f'
    assert hexdigests[99].hexdigest == '0x50fe1962c4965880'
    assert words[0].words == 'INCH SEA ANNE LONG AHEM TOUR'
    assert words[1].words == 'EASE OIL FUM CURE AWRY AVIS'
    assert words[99].words == 'BAIL TUFT BITS GANG CHEF THY'

    # pass='AbCdEfGhIjK', seed='alpha1'
    gen = otp2289.OTPGenerator(b'AbCdEfGhIjK', 'alpha1', otp2289.OTP_ALGO_MD5)
    response = gen.generate_otp_response(0)
    assert response.hexdigest == '0x87066dd9644bf206'
    assert response.words == 'FULL PEW DOWN ONCE MORT ARC'
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0x7cd34c1040add14b'
    assert response.words == 'FACT HOOF AT FIST SITE KENT'
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0x5aa37a81f212146c'
    assert response.words == 'BODE HOP JAKE STOW JUT RAP'

    # pass="OTP's are good", seed='correct'
    gen = otp2289.OTPGenerator(
        b"OTP's are good", 'correct', otp2289.OTP_ALGO_MD5
    )
    response = gen.generate_otp_response(0)
    assert response.hexdigest == '0xf205753943de4cf9'
    assert response.words == 'ULAN NEW ARMY FUSE SUIT EYED'
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0xddcdac956f234937'
    assert response.words == 'SKIM CULT LOB SLAM POE HOWL'
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0xb203e28fa525be47'
    assert response.words == 'LONG IVY JULY AJAR BOND LEE'


def test_otp_response() -> None:
    """Tests OTPResponse"""
    gen = otp2289.OTPGenerator(
        b'This is a test.', 'TeSt', otp2289.OTP_ALGO_MD5
    )
    response = gen.generate_otp_response(0)
    assert response.response_bytes == bytes(response)

    # From 'RFC-2289 Appendix C - OTP Verification Examples'
    # hexdigest: 9e876134d90499dd
    # words: INCH SEA ANNE LONG AHEM TOUR
    response_from_tokens = otp2289.OTPResponse.from_tokens(
        'INCH SEA ANNE LONG AHEM TOUR'
    )
    response_from_hex1 = otp2289.OTPResponse.from_hex('9e876134d90499dd')
    response_from_hex2 = otp2289.OTPResponse.from_hex('0x9e876134d90499dd')
    assert (
        response_from_tokens.response_bytes
        == response_from_hex1.response_bytes
    )
    assert (
        response_from_tokens.response_bytes
        == response_from_hex2.response_bytes
    )

    # same tests, only using __eq__
    assert response_from_tokens == response_from_hex1
    assert response_from_tokens == response_from_hex2


def test_otp_response_exceptions() -> None:
    """Tests OTPResponse exceptions"""
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_hex(
            b'9e876134d90499dd'  # ty: ignore[invalid-argument-type]
        )
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == 'OT-hex must be a str'
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_hex('9e876134d90499d')
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == (
        'The length of the hex should be 16 (representing 64 bits digest)'
    )
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_hex('9e876134d90499dg')
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == 'Invalid OT-hex'

    # .from_tokens
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_tokens(
            b'INCH SEA ANNE LONG AHEM TOUR'  # ty: ignore[invalid-argument-type]
        )
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == 'tokens must be a str'
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_tokens('INCH SEA ANNE LONG AHEM')
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == 'Tokens-string does not contain 6 tokens'
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_tokens('INCH SEA ANNE LONG AHEM SIMEON')
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == (
        'One or more words not present in RFC1760'
    )
    with pytest.raises(otp2289.OTPResponseError) as exc_info:
        otp2289.OTPResponse.from_tokens('INCH SEA ANNE LONG AHEM LEE')
    assert exc_info.type is otp2289.OTPResponseError
    assert exc_info.value.args[0] == 'Invalid bit checksum'


def test_sha1() -> None:
    """
    Tests the SHA-1 functionality of the OTPGenerator as described in the RFC

    Those are the tests from 'RFC-2289 Appendix C - OTP Verification Examples'
    """
    # pass='This is a test.', seed='TeSt'
    gen = otp2289.OTPGenerator(
        b'This is a test.', 'TeSt', otp2289.OTP_ALGO_SHA1
    )
    response = gen.generate_otp_response(step=0)
    assert isinstance(response, otp2289.OTPResponse)
    assert isinstance(response.words, str)
    assert isinstance(response.hexdigest, str)
    assert response.hexdigest == '0xbb9e6ae1979d8ff4'
    assert response.words == 'MILT VARY MAST OK SEES WENT'
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0x63d936639734385b'
    assert response.words == 'CART OTTO HIVE ODE VAT NUT'
    assert (
        gen.generate_otp_response_from_challenge('otp-sha1 1 TeSt').hexdigest
        == '0x63d936639734385b'
    )
    assert (
        gen.generate_otp_response_from_challenge('otp-sha1 1 TeSt').words
        == 'CART OTTO HIVE ODE VAT NUT'
    )
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0x87fec7768b73ccf9'
    assert response.words == 'GAFF WAIT SKID GIG SKY EYED'
    assert (
        gen.generate_otp_response_from_challenge(
            'otp-sha1 99   TeSt'
        ).hexdigest
        == '0x87fec7768b73ccf9'
    )
    assert (
        gen.generate_otp_response_from_challenge('otp-sha1 99  TeSt').words
        == 'GAFF WAIT SKID GIG SKY EYED'
    )

    # iterator test
    hexdigests = list(gen.otp_response_range(105))
    words = list(gen.otp_response_range(99))
    hexdigests.reverse()
    words.reverse()
    assert hexdigests[0].hexdigest == '0xbb9e6ae1979d8ff4'
    assert hexdigests[1].hexdigest == '0x63d936639734385b'
    assert hexdigests[99].hexdigest == '0x87fec7768b73ccf9'
    assert words[0].words == 'MILT VARY MAST OK SEES WENT'
    assert words[1].words == 'CART OTTO HIVE ODE VAT NUT'
    assert words[99].words == 'GAFF WAIT SKID GIG SKY EYED'

    # pass='AbCdEfGhIjK', seed='alpha1'
    gen = otp2289.OTPGenerator(b'AbCdEfGhIjK', 'alpha1', otp2289.OTP_ALGO_SHA1)
    response = gen.generate_otp_response(0)
    assert response.hexdigest == '0xad85f658ebe383c9'
    assert response.words == 'LEST OR HEEL SCOT ROB SUIT'
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0xd07ce229b5cf119b'
    assert response.words == 'RITE TAKE GELD COST TUNE RECK'
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0x27bc71035aaf3dc6'
    assert response.words == 'MAY STAR TIN LYON VEDA STAN'

    # pass="OTP's are good", seed='correct'
    gen = otp2289.OTPGenerator(
        b"OTP's are good", 'correct', otp2289.OTP_ALGO_SHA1
    )
    response = gen.generate_otp_response(0)
    assert response.hexdigest == '0xd51f3e99bf8e6f0b'
    assert response.words == 'RUST WELT KICK FELL TAIL FRAU'
    response = gen.generate_otp_response(1)
    assert response.hexdigest == '0x82aeb52d943774e4'
    assert response.words == 'FLIT DOSE ALSO MEW DRUM DEFY'
    response = gen.generate_otp_response(99)
    assert response.hexdigest == '0x4f296a74fe1567ec'
    assert response.words == 'AURA ALOE HURL WING BERG WAIT'