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Groups > comp.lang.c > #379419
| From | bart <bc@freeuk.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Inconsistent... |
| Date | 2023-10-31 18:35 +0000 |
| Organization | i2pn2 (i2pn.org) |
| Message-ID | <uhrhdm$3edkt$1@i2pn2.org> (permalink) |
| References | (1 earlier) <uhpdrm$3blvk$1@i2pn2.org> <uhpndq$3c4tj$1@i2pn2.org> <87lebjqb6g.fsf@bsb.me.uk> <uhr28e$3dnb9$1@i2pn2.org> <87fs1qrcns.fsf@bsb.me.uk> |
[Another repost as i2pn2 not always sending my messges]
On 31/10/2023 16:15, Ben Bacarisse wrote:
> bart <bc@freeuk.com> writes:
>
>> [Reposting as the original reply seems to have vanished, but it may
>> reappear]
>>
>> On 31/10/2023 11:32, Ben Bacarisse wrote:
>>> bart <bc@freeuk.com> writes:
>>>
>>>> On 30/10/2023 23:22, bart wrote:
>>>>> On 30/10/2023 21:01, Chris M. Thomasson wrote:
>>>
>>>>> I tweaked the source code (used explicit assignment to fields of some
>>>>> structs) to be able to use my compilers.
>>>>> Then I tried these compilers:
>>>>> gcc 13.2.0 - this worked. (I assume it is supposed to show some
>>>>> plaintext, encrypted text starting "fog.IiQ' U'?zDjP))v$oN)?z<xT
>>>>> CAPNKUfB...", then the identical plaintext)
>>>>> tcc - failed. The encrypted text started
>>>>> "xy,$}lu~@NM*a%^z1YA+'N@9yrV]E...", and the decrypted was:
>>>>>
>>
"dEjtkuXVjq5*uzqpWXE6tkzXVjq5czuqpWXE!t9zX\j35czu30/XE!tkuX\!qocuu3pWXEjtkzXVj3oczuq4WXE!0
>>>>> kz.Vjqocuu3p/TEj0ku.Vj31cuz3pWXEjtkzXVj3o*uzq4W."
>>>>
>>>> Regarding tcc, a few things differ internally, but I think one clue is
>> here:
>>>>
>>>> #define CT_MBROT_ABET_LOOKUP(mp_char) \
>>>> ((strchr(CT_MBROT_ABET, (mp_char))) - CT_MBROT_ABET)
>>>>
>>>> This is effectively doing the following (to get an offset into the
>> string?):
>>>>
>>>> str("ABC", c) - "ABC";
>>>>
>>>> It is assuming that both string literals have the same address.
>>>
>>> This is an unwarranted assumption.
>>>
>>> But the result is also undefined when mp_char does not occur in the
>>> string which can happen for two printable ASCII characters.
>>>
>>> Chris, you should test your code more thoroughly.
>>>
>>>> If I move that string into a variable, then Tcc starts to work. So
does
>>>> bcc.
>>>
>>> Saying that tcc starts to work when you fix the bug suggests that tcc
>>> was not working before, but it's the code that was not working. tcc
>>> (and presumably bcc) were working fine all along.
>>>
>>>> lccwin32 still has a problem.
>>>
>>> What's the problem? Are you sure it's lccwin32 and not the source code
>>> that has the problem?
>>
>> When I say that compiler X has a problem, obviously I mean that the
program
>> built with X shows an error.
>
> That's a very odd way of putting it. My guess is that the
> program has multiple meanings (and in some cases none). The compiler is
> (probably) correctly picking one of them.
>
>> That is, the results are incorrect.
>
> Ah, then you know more that I. What are the correct results?
No spec is given. But I would say one requirement is that encrypting and
then decrypting a piece of plain text should produce the original text.
Another is that encrypted text should be secret, but lccwin32 for
example had that be the same as the plaintext! I assumed that was wrong.
There may be others to do with quality of the encryption, as well as
consistency of the encrpted data across compilers, but those two are
what stood out for me when I ran the program and which seemed obviously
wrong.
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Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:01 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:11 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 14:30 -0700
Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-10-30 22:01 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-30 15:09 -0700
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-30 23:22 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-30 23:44 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 02:05 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-31 11:32 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 14:16 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-31 16:15 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 18:35 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 14:05 -0700
Re: Inconsistent... bart <bc@freeuk.com> - 2023-10-31 22:29 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 00:39 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 10:35 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:29 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:52 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 14:30 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 13:37 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 00:44 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 20:26 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 11:05 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 10:59 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-01 13:01 +0100
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:52 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-01 20:12 +0100
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:52 -0700
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 10:04 +0100
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 10:51 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 11:02 -0700
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 20:02 +0100
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 12:03 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 23:57 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-04 00:11 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 20:28 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-03 10:23 +0100
[OT] Encryption (Was: Inconsistent...) Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-03 10:10 +0000
Re: [OT] Encryption (Was: Inconsistent...) David Brown <david.brown@hesbynett.no> - 2023-11-03 15:01 +0100
Re: [OT] Encryption (Was: Inconsistent...) scott@slp53.sl.home (Scott Lurndal) - 2023-11-03 16:52 +0000
Re: [OT] Encryption (Was: Inconsistent...) "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 15:12 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-03 15:11 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 13:43 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 12:53 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 20:08 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 13:12 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:12 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 14:16 -0700
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:43 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-01 16:02 -0700
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-01 22:59 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-10-30 23:52 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 13:45 -0700
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-10-31 14:29 -0700
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 10:10 +0100
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 09:52 +0000
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 11:31 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 13:52 +0100
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 14:07 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 16:53 +0100
Re: Inconsistent... bart <bc@freeuk.com> - 2023-11-02 19:15 +0000
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-03 10:33 +0100
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-02 20:43 +0000
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-02 13:47 -0700
Re: Inconsistent... David Brown <david.brown@hesbynett.no> - 2023-11-02 13:34 +0100
Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-11-01 20:32 +0000
Re: Inconsistent... Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-11-01 21:36 +0000
Re: Inconsistent... Richard Harnden <richard.nospam@gmail.invalid> - 2023-11-01 21:54 +0000
Re: Inconsistent... Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-11-09 15:54 -0800
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-09 01:16 -0800
Re: Inconsistent... "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2023-11-10 21:02 -0800
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