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Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems]

From Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups linux.debian.user
Subject Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems]
Date 2021-03-05 07:40 +0100
Message-ID <BPchY-ak-5@gated-at.bofh.it> (permalink)
References (4 earlier) <BOLhM-8mE-5@gated-at.bofh.it> <BORQd-3YF-1@gated-at.bofh.it> <BP4DL-3LZ-1@gated-at.bofh.it> <BP8R3-6jY-1@gated-at.bofh.it> <BPbce-7Xi-3@gated-at.bofh.it>
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> AIUI compilers have been studied so extensively that their production is
> largely automated.

Oh, no.  There are some parts we know how to automate, but by and large
it's all hand written code.

> Create an EBNF specification, feed it through a tool
> chain (lex, yacc, cc, as, ld, etc.), and you end up with a compiler.

The EBNF specification only gives you the syntax of the source language.
It's barely sufficient for a pretty printer, but lacks all the
information about typing rules and dynamic semantics of the source
language, as well as any information about the syntax and semantics of
the target language, and doesn't say anything about to optimize the
code either.

The part you can automate with lex/yacc and friends is a tiny fraction
of a compiler, except for very naive toy compilers.

> The process is known and the results are predictable; especially with
> standards-based languages such as C.  So, a skilled attacker will know
> what you're doing, how you are doing it, and may be able to produce a
> 'cA' that infects both 'A' and 'T'.

That is a risk, indeed.

> If you are going to produce source code for a trusted compiler 'T', then you
> should also produce an executable 'cT'.

That could be significantly harder.

> AIUI this can be done by writing a simplified compiler in some other
> language 'a',

Indeed, actually your trusted compiler `T` doesn't need to be compiled
with `cA` (nor written in the same source language), it just needs to be
used somehow to compile `A` to `cA2` so it can be compared to `cA` to
see if there's a backdoor.


        Stefan

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Thread

Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-02 21:10 +0100
  Re: Installation problems Brian <ad44@cityscape.co.uk> - 2021-03-02 21:40 +0100
    Re: Installation problems Weaver <weaver@riseup.net> - 2021-03-02 22:20 +0100
      Re: Installation problems <tomas@tuxteam.de> - 2021-03-02 22:30 +0100
        Re: Installation problems Brian <ad44@cityscape.co.uk> - 2021-03-03 00:10 +0100
    Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-02 22:50 +0100
      Re: Installation problems "Andrew M.A. Cater" <amacater@einval.com> - 2021-03-02 23:20 +0100
        Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 02:40 +0100
          Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 02:50 +0100
      Re: Installation problems Keith Bainbridge <ke1thozgroups@gmx.com> - 2021-03-03 00:00 +0100
        Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 10:30 +0100
          Re: Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-03 15:40 +0100
            Re: Installation problems Celejar <celejar@gmail.com> - 2021-03-03 16:40 +0100
            Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 16:40 +0100
              Re: Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-03 22:40 +0100
                Re: Installation problems Joe <joe@jretrading.com> - 2021-03-03 23:00 +0100
                Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-04 13:00 +0100
                Re: Installation problems Tixy <tixy@yxit.co.uk> - 2021-03-04 13:30 +0100
                Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-04 14:00 +0100
                Re: Installation problems Felix Miata <mrmazda@earthlink.net> - 2021-03-04 17:30 +0100
    Re: Installation problems Keith Bainbridge <ke1thozgroups@gmx.com> - 2021-03-02 23:50 +0100
      Re: Installation problems David Wright <deblis@lionunicorn.co.uk> - 2021-03-03 03:50 +0100
        Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 10:50 +0100
          Re: Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 11:20 +0100
    Re: Installation problems Keith Bainbridge <ke1thozgroups@gmx.com> - 2021-03-03 00:00 +0100
  PARTIAL DIAGNOSIS of Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-03 16:30 +0100
    Re: PARTIAL DIAGNOSIS of Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-03 22:30 +0100
      Re: PARTIAL DIAGNOSIS of Installation problems Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-03 23:00 +0100
        Re: PARTIAL DIAGNOSIS of Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-04 02:50 +0100
          Re: PARTIAL DIAGNOSIS of Installation problems Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-04 03:50 +0100
            Re: PARTIAL DIAGNOSIS of Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-04 04:20 +0100
              Re: PARTIAL DIAGNOSIS of Installation problems Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-04 05:10 +0100
                Re: PARTIAL DIAGNOSIS of Installation problems <tomas@tuxteam.de> - 2021-03-04 10:00 +0100
          Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] <tomas@tuxteam.de> - 2021-03-04 09:50 +0100
            Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Joe <joe@jretrading.com> - 2021-03-04 10:50 +0100
              Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] <tomas@tuxteam.de> - 2021-03-04 14:20 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 15:30 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] tomas@tuxteam.de - 2021-03-04 16:20 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 17:20 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] tomas@tuxteam.de - 2021-03-04 19:10 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 19:30 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-04 23:20 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] <tomas@tuxteam.de> - 2021-03-04 23:40 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Joe <joe@jretrading.com> - 2021-03-04 23:50 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 15:30 +0100
              Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 14:20 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Joe <joe@jretrading.com> - 2021-03-04 16:10 +0100
                Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation  problems] Celejar <celejar@gmail.com> - 2021-03-04 17:20 +0100
                OT: Bathroom scales (was: Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems]) rhkramer@gmail.com - 2021-03-04 17:40 +0100
            Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] David Christensen <dpchrist@holgerdanske.com> - 2021-03-04 23:30 +0100
              [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-05 04:00 +0100
                Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of  Installation problems] David Christensen <dpchrist@holgerdanske.com> - 2021-03-05 06:30 +0100
                Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of  Installation problems] David Christensen <dpchrist@holgerdanske.com> - 2021-03-05 06:40 +0100
                Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] Stefan Monnier <monnier@iro.umontreal.ca> - 2021-03-05 07:40 +0100
                Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of  Installation problems] <tomas@tuxteam.de> - 2021-03-05 09:20 +0100
                Re: [OFFTOPIC] Re: Trusting trust [was: PARTIAL DIAGNOSIS of Installation problems] Gene Heskett <gheskett@shentel.net> - 2021-03-05 15:10 +0100
    Re: PARTIAL DIAGNOSIS of Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-04 13:30 +0100
      Re: PARTIAL DIAGNOSIS of Installation problems David Wright <deblis@lionunicorn.co.uk> - 2021-03-04 18:50 +0100
      Re: PARTIAL DIAGNOSIS of Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-04 23:50 +0100
        Re: PARTIAL DIAGNOSIS of Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-05 13:20 +0100
          Re: PARTIAL DIAGNOSIS of Installation problems David Christensen <dpchrist@holgerdanske.com> - 2021-03-05 21:30 +0100
            Re: PARTIAL DIAGNOSIS of Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-05 22:20 +0100
              Re: PARTIAL DIAGNOSIS of Installation problems Joe <joe@jretrading.com> - 2021-03-05 22:50 +0100
                Re: PARTIAL DIAGNOSIS of Installation problems Richard Owlett <rowlett@cloud85.net> - 2021-03-05 23:30 +0100
                Re: PARTIAL DIAGNOSIS of Installation problems Charles Curley <charlescurley@charlescurley.com> - 2021-03-06 00:40 +0100
                Re: PARTIAL DIAGNOSIS of Installation problems Celejar <celejar@gmail.com> - 2021-03-07 01:40 +0100
    Re: PARTIAL DIAGNOSIS of Installation problems David Wright <deblis@lionunicorn.co.uk> - 2021-03-06 02:50 +0100
    Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-08 13:10 +0100
      Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} "Andrew M.A. Cater" <amacater@einval.com> - 2021-03-08 13:30 +0100
      Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} songbird <songbird@anthive.com> - 2021-03-08 17:30 +0100
        Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-08 20:20 +0100
          Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} songbird <songbird@anthive.com> - 2021-03-09 02:10 +0100
        Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-09 13:40 +0100
          Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Anssi Saari <as@sci.fi> - 2021-03-09 14:00 +0100
            Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Joe <joe@jretrading.com> - 2021-03-09 14:20 +0100
          Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Andrei POPESCU <andreimpopescu@gmail.com> - 2021-03-09 14:10 +0100
            Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Joe <joe@jretrading.com> - 2021-03-09 14:20 +0100
            Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-09 21:40 +0100
              Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Andrei POPESCU <andreimpopescu@gmail.com> - 2021-03-10 10:50 +0100
                Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-10 11:30 +0100
                Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Andrei POPESCU <andreimpopescu@gmail.com> - 2021-03-10 14:40 +0100
                Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Richard Owlett <rowlett@cloud85.net> - 2021-03-10 15:50 +0100
                Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} Andrei POPESCU <andreimpopescu@gmail.com> - 2021-03-10 21:50 +0100
                Re: Status update {Re: PARTIAL DIAGNOSIS of Installation problems} "Andrew M.A. Cater" <amacater@einval.com> - 2021-03-11 00:20 +0100

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