[PATCH] chomp to remove '\r' as well

[PATCH] chomp to remove '\r' as well

[Mads Martin Joergensen]

Hey together,

Anyone object to this behaviour? Just heard on irc someone got bitten by
this:

--- chomp.c     20 Feb 2006 05:00:09 -0000      1.4
+++ chomp.c     11 Sep 2006 12:34:28 -0000
@@ -38,7 +38,7 @@

        i = strlen(str) - 1;

-       while(str[i] = '\n') {
+       while(str[i] = '\n' || str[i] = '\r') {
                str[i] = 0;
                i--;
        }

-- 
Mads Martin Joergensen, http://mmj.dk
"Why make things difficult, when it is possible to make them cryptic
 and totally illogical, with just a little bit more effort?"
                                 -- A. P. J.

Re: [PATCH] chomp to remove '\r' as well

[Joel Aelwyn]

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On Mon September 11 2006 06:35, Mads Martin Joergensen Mads Martin 
Joergensen <mmj@mmj.dk> wrote:
> Hey together,
>
> Anyone object to this behaviour? Just heard on irc someone got bitten
> by this:
>
> --- chomp.c     20 Feb 2006 05:00:09 -0000      1.4
> +++ chomp.c     11 Sep 2006 12:34:28 -0000
> @@ -38,7 +38,7 @@
>
>         i = strlen(str) - 1;
>
> -       while(str[i] == '\n') {
> +       while(str[i] == '\n' || str[i] == '\r') {
>                 str[i] = 0;
>                 i--;
>         }

As far as I recall, getting anything with \r\n as an EOL pretty much 
grossly violates the SMTP RFCs, so I'll make two suggestions about 
this:

1) Limit it *strictly* to a single \r\n, not any random combination of 
the two characters. You'll drastically reduce your chances of subtle 
and nasty misbehaviours being introduced when (not if) some software 
comes along and relies on things obeying the RFCs.

2) Make it a configurable option. Call it 'broken-CRLF-support' or 
somesuch, because it most assuredly is.

Outlook is one of the primary offenders in this arena, for what it's 
worth; DJB had -- probably has -- a rant up about it and why qmail 
does/did not support a similar feature (it's been years since I used 
qmail, but the combination of the two provided no end of headaches back 
when I had to deal with them both at my workplace... and, to a one, 
they were caused by Outlook blatantly violating the protocol 
specifications.

-- 
Joel Aelwyn <joel@lightbearer.com>

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Re: [PATCH] chomp to remove '\r' as well

[Mads Martin Joergensen]

* Joel Aelwyn <joel@lightbearer.com> [Sep 11. 2006 15:12]:
> > Anyone object to this behaviour? Just heard on irc someone got bitten
> > by this:
> >
> > --- chomp.c     20 Feb 2006 05:00:09 -0000      1.4
> > +++ chomp.c     11 Sep 2006 12:34:28 -0000
> > @@ -38,7 +38,7 @@
> >
> >         i = strlen(str) - 1;
> >
> > -       while(str[i] = '\n') {
> > +       while(str[i] = '\n' || str[i] = '\r') {
> >                 str[i] = 0;
> >                 i--;
> >         }
> 
> As far as I recall, getting anything with \r\n as an EOL pretty much 
> grossly violates the SMTP RFCs, so I'll make two suggestions about 
> this:
> 
> 1) Limit it *strictly* to a single \r\n, not any random combination of 
> the two characters. You'll drastically reduce your chances of subtle 
> and nasty misbehaviours being introduced when (not if) some software 
> comes along and relies on things obeying the RFCs.
> 
> 2) Make it a configurable option. Call it 'broken-CRLF-support' or 
> somesuch, because it most assuredly is.
> 
> Outlook is one of the primary offenders in this arena, for what it's 
> worth; DJB had -- probably has -- a rant up about it and why qmail 
> does/did not support a similar feature (it's been years since I used 
> qmail, but the combination of the two provided no end of headaches back 
> when I had to deal with them both at my workplace... and, to a one, 
> they were caused by Outlook blatantly violating the protocol 
> specifications.

Ah, this has nothing to do with the smtp layer. SMTP always have to have
\r\n, and that's handled in send.

Problem is that when I for instance read a subscriber from a subscribers
file with the old behaviour and match

"mmj@mmj.dk" with "mmj@mmj.dk^M", they're different.

Same thing when reading control files.

-- 
Mads Martin Joergensen, http://mmj.dk
"Why make things difficult, when it is possible to make them cryptic
 and totally illogical, with just a little bit more effort?"
                                 -- A. P. J.

Re: [PATCH] chomp to remove '\r' as well

[Joel Aelwyn]

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On Mon September 11 2006 07:18, Mads Martin Joergensen Mads Martin 
Joergensen <mmj@mmj.dk> wrote:
> * Joel Aelwyn <joel@lightbearer.com> [Sep 11. 2006 15:12]:
> > > Anyone object to this behaviour? Just heard on irc someone got
> > > bitten by this:
> > >
> > > --- chomp.c     20 Feb 2006 05:00:09 -0000      1.4
> > > +++ chomp.c     11 Sep 2006 12:34:28 -0000
> > > @@ -38,7 +38,7 @@
> > >
> > >         i = strlen(str) - 1;
> > >
> > > -       while(str[i] == '\n') {
> > > +       while(str[i] == '\n' || str[i] == '\r') {
> > >                 str[i] = 0;
> > >                 i--;
> > >         }
> >
> > As far as I recall, getting anything with \r\n as an EOL pretty
> > much grossly violates the SMTP RFCs, so I'll make two suggestions
> > about this:
> >
> > 1) Limit it *strictly* to a single \r\n, not any random combination
> > of the two characters. You'll drastically reduce your chances of
> > subtle and nasty misbehaviours being introduced when (not if) some
> > software comes along and relies on things obeying the RFCs.
> >
> > 2) Make it a configurable option. Call it 'broken-CRLF-support' or
> > somesuch, because it most assuredly is.
> >
> > Outlook is one of the primary offenders in this arena, for what
> > it's worth; DJB had -- probably has -- a rant up about it and why
> > qmail does/did not support a similar feature (it's been years since
> > I used qmail, but the combination of the two provided no end of
> > headaches back when I had to deal with them both at my workplace...
> > and, to a one, they were caused by Outlook blatantly violating the
> > protocol specifications.
>
> Ah, this has nothing to do with the smtp layer. SMTP always have to
> have \r\n, and that's handled in send.
>
> Problem is that when I for instance read a subscriber from a
> subscribers file with the old behaviour and match
>
> "mmj@mmj.dk" with "mmj@mmj.dk^M", they're different.
>
> Same thing when reading control files.

Ah, ick. But, in that case, being fancy is probably not warranted... 
anyone who would get bitten by the broader behaviour is already doing 
something they need to be smacked for. Comments withdrawn, or at least 
deferred into the 'nice idea, maybe, but then again maybe not' 
bucket. :)
-- 
Joel Aelwyn <joel@lightbearer.com>

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Re: [PATCH] chomp to remove '\r' as well

[Morten K. Poulsen]

On Mon, 11 Sep 2006 14:35:59 +0200, Mads Martin Joergensen <mmj@mmj.dk> wrote:
> Anyone object to this behaviour?
[snip]
> -       while(str[i] = '\n') {
> +       while(str[i] = '\n' || str[i] = '\r') {

Fine by me.

Was the guy using the twisted BSD variant from Apple Computer, which uses \r and not \n?

Morten

-- 
Morten K. Poulsen <morten@afdelingp.dk>
http://www.afdelingp.dk/

Re: [PATCH] chomp to remove '\r' as well

[Mads Martin Joergensen]

* Morten K. Poulsen <morten@afdelingp.dk> [Sep 11. 2006 20:14]:
> 
> On Mon, 11 Sep 2006 14:35:59 +0200, Mads Martin Joergensen <mmj@mmj.dk> wrote:
> > Anyone object to this behaviour?
> [snip]
> > -       while(str[i] = '\n') {
> > +       while(str[i] = '\n' || str[i] = '\r') {
> 
> Fine by me.
> 
> Was the guy using the twisted BSD variant from Apple Computer, which uses \r and not \n?

No, his sysadmins based on windows added ^M's. BSD wouldn't even think
of such--albeit Apply have touched it :)

-- 
Mads Martin Joergensen, http://mmj.dk
"Why make things difficult, when it is possible to make them cryptic
 and totally illogical, with just a little bit more effort?"
                                 -- A. P. J.

Re: [PATCH] chomp to remove '\r' as well

[Morten K. Poulsen]

Mads Martin Joergensen <mmj@mmj.dk> wrote:
> * Morten K. Poulsen <morten@afdelingp.dk> [Sep 11. 2006 20:14]:
>> Was the guy using the twisted BSD variant from Apple Computer, which
>> uses \r and not \n?
>
> No, his sysadmins based on windows added ^M's. BSD wouldn't even think
> of such--albeit Apply have touched it :)

Hehe, I see. I thought the Macintoshes still used only \r, but they stopped doing that in Mac OS X. Probably a wise decision :)

Morten

--
Morten K. Poulsen <morten@afdelingp.dk>
http://www.afdelingp.dk/