Re: [9fans] Inferno plug-in security

Re: [9fans] Inferno plug-in security

[erik quanstrom]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 2329 bytes --]

if i understand, you are addressing a situation like
a web page which may have all kinds of unknown modules,
etc.

if that is the case, then i don't believe that signing is
security. just because the module came from microsoft and
was signed with the super-private microsoft key, doesn't
mean that the module doesn't do things that you don't allow.
hey, the key could have been stolen (what would be the chances ;-)
or it might just be buggy (what would be the chances).

i think that you are going to have to run dis modules loaded
in a situation like a web browser into a sandbox that has
very restricted premissions in order to avoid security issues.
in that case, there's not much point to all the complication
of signing.

erik

----------------

//the basic idea in all Plan 9 and Inferno is, that even network connections
//are services offered by directories which are called "file systems"

you're correct, of cource. but think about it in terms of a normal file system,
like local disk or such. different users have different permissions to different
things, right? we can tell these users are different people because they have a
certain key/passwd/response. without signing on a dis module, we face two
problems, both of which exist in any system with no authentication. first,
when someone does something we don't like, we don't know who to blame.
if someone's doing things i don't like on my system, i want to know about it.
similarly, if i load a dis module that does things i don't like, i want to know
who wrote it and/or who gave it to me. second, without any reasonable
method of telling who's who, if i want to restrict _someone_ from doing
something, i have to restrict _everyone_. if, for example, i trust myself, VN,
and the Labs to write modules that make network connections, but not
anyone else, i need to tell who wrote a given module, right? otherwise it's
all-or-none. i'm either too restrictive or too permissive.

security consists of (at least?) two parts: authentication (who am i) and
authorization (what can i do). the file system model is an excelent way of
taking care of authorization, but something still needs to be done for
authentication, so i can trust people are who they say they are. dis signing
is one suggestion of how to do it.
-α.

[9fans] Highlighting in Acme

[Dharani Vilwanathan]

Hi,

If I have to highlight a portion of text, say character 4 to 8 in line 5, in
a window in Acme, how can I do it through Acme interface?

Thanks
dharani

Re: [9fans] Highlighting in Acme

[Dan Cross]

> When the new distribution happens, very soon I hope, this and many other
> bugs will be fixed, along with the addition of lots of new ones.

Does this man that Plan 9 is approaching some kind of steady state
of equalibrium where the number of bugs fixed is exactly equal to
the number of bugs introduced in any given release?

	- Dan C.

Re: [9fans] Highlighting in Acme

[Dharani Vilwanathan]

Rob,

> You can fix the silly acme bug by adding the second condition
> in this if from number() in /sys/src/cmd/acme/addr.c
>
> Forward:
> while(line>0 && q1<t->file->nc)
> if(textreadc(t, q1++) == '\n' || q1==t->file->nc)
> if(--line > 0)
> q0 = q1;
>
> When the new distribution happens, very soon I hope, this and many other
> bugs will be fixed, along with the addition of lots of new ones.

Thanks for the quick response and fix.

Regards
dharani

Re: [9fans] Highlighting in Acme

[rob pike, esq.]

You can fix the silly acme bug by adding the second condition
in this if from number() in /sys/src/cmd/acme/addr.c

	Forward:
		while(line>0 && q1<t->file->nc)
			if(textreadc(t, q1++) == '\n' || q1==t->file->nc)
				if(--line > 0)
					q0 = q1;

When the new distribution happens, very soon I hope, this and many other
bugs will be fixed, along with the addition of lots of new ones.

-rob

Re: [9fans] Highlighting in Acme

[rob pike, esq.]

OK, I think it all works if the file has a newline on the end.
Without the newline, 3-#0 is mishandled by acme.  I'll keep
digging.

-rob

Re: [9fans] Highlighting in Acme

[rob pike, esq.]

>    % echo '2-#0+#5,3-#0+#4' > /mnt/acme/9/addr
>    echo: write error: bad address syntax

The syntax error is because you need to say echo -n.
Then you get
	echo: write error: address out of range
because of some stupid bug that stops 3-#0 working
right even though 2-#0 works fine.  I'm digging.

-rob

Re: [9fans] Highlighting in Acme

[Dharani Vilwanathan]

rog,

Sorry for bringing up this topic too late. I had a question on Acme
highlighting and you answered it long back.

I tried this option and it didnt seem to work for me with the file
interface. It does work with the right button.

This is what I did. I created a 3 line file say test1:

    % cat test1
    1234567890
    1234567890
    1234567890

Then I opened this file in acme and wrote the following:

    % echo '2-#0+#5,3-#0+#4' > /mnt/acme/9/addr
    echo: write error: bad address syntax
    % echo ':2-#0+#5,3-#0+#4' > /mnt/acme/9/addr
    echo: write error: bad address syntax

Both the writes are failing. Sweeping ":2-#0+#5,3-#0+#4" with right button
pressed works, however.

Am I making any mistake?

Next, I noticed limbo compiler produces something like "test.b:10.5..." in
test.s output. But Acme didnt recognize this addressing properly. Is it that
the corresponding code is not in Acme yet? If so, when will it be available?
Will it be available in both Plan 9 and Inferno versions?

Actually this is an elegant addition to Acme. Addressing a text with
lpos1:cpos1 and lpos2:cpos2 is appealing. This will make things clean.

Thanks
dharani


> bell-labs.com!dharani wrote:
> > If I have to highlight a portion of text, say character 4 to 8 in line
5, in
> > a window in Acme, how can I do it through Acme interface?
>
> when you say "Acme interface" i don't know whether you mean the Acme
> user interface or the Acme program (filesystem) interface.
>
> you've chosen a task that's possible, but not elegant from the user
> interface:  right button click on the text:
> :5-#0+#4,5-#0+#8
> or alternatively:
> :5-#0+#4;+#4
>
> you can give an arbitrary sam-style address there.
> given that the Limbo compiler holds file positions in line.charpos
> format, i was considering adding a hack to my local acme
> that would understand:
>
> :5.4,5.8
>
> and then the compiler could spit out more detailed positions
> that acme could understand (having the compiler spit
> out:
>
> file.b:100-#0+#20,101-#0+#30: some error
>
> seems a bit uncomfortable).
> if you want to do this through the filesystem interface,
> write the address to the addr file, and write "dot=addr" to
> the ctl file.
>
> read the manual.
>
>   cheers,
>     rog.
>

Re: [9fans] Highlighting in Acme

[rog]

bell-labs.com!dharani wrote:
> If I have to highlight a portion of text, say character 4 to 8 in line 5, in
> a window in Acme, how can I do it through Acme interface?

when you say "Acme interface" i don't know whether you mean the Acme
user interface or the Acme program (filesystem) interface.

you've chosen a task that's possible, but not elegant from the user
interface:  right button click on the text:
	:5-#0+#4,5-#0+#8
or alternatively:
	:5-#0+#4;+#4

you can give an arbitrary sam-style address there.
given that the Limbo compiler holds file positions in line.charpos
format, i was considering adding a hack to my local acme
that would understand:

	:5.4,5.8

and then the compiler could spit out more detailed positions
that acme could understand (having the compiler spit
out:

	file.b:100-#0+#20,101-#0+#30: some error

seems a bit uncomfortable).
if you want to do this through the filesystem interface,
write the address to the addr file, and write "dot=addr" to
the ctl file.

read the manual.

  cheers,
    rog.