From mboxrd@z Thu Jan 1 00:00:00 1970
From: Adolf Belka <adolf.belka@ipfire.org>
To: development@lists.ipfire.org
Subject: Re: [PATCH] logo.cgi: Fix for bug13795 - captive portal not
displaying uploaded logo
Date: Mon, 06 Jan 2025 18:51:45 +0100
Message-ID: <46c058e6-c1b5-4951-a50c-1ba0d5b9f464@ipfire.org>
In-Reply-To: <FB234067-C12C-4254-875E-716BD59EC1AC@ipfire.org>
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="===============1120444248710799027=="
List-Id: <development.lists.ipfire.org>
--===============1120444248710799027==
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Hi Michael,
On 06/01/2025 17:28, Michael Tremer wrote:
> Hello Adolf,
>=20
> I assume this might not fully fix the problem since we don=E2=80=99t know f=
or certain if the uploaded file is a JPEG file.
I am sorry, I had intended to put something about that into the commit=20
but I forgot to do it.
I had various image files which I could check the type of and I found a=20
jpg, a png and a tiff image file.
I uploaded each of these in turn and the same image/jpeg content type=20
successfully displayed the uploaded image onto the browser screen.
>=20
> I believe this is why have chosen something very generic instead of a speci=
fic image type. I assume that we would have to run something to check the cor=
rect MIME type of the file before we can send anything.
Of course it might be that how I have done it works for now for any=20
(most/some) image files but it could also change in the future.
>=20
> https://metacpan.org/release/FITZNER/File-LibMagic-0.96/view/LibMagic.pm
>=20
> This could do the job.
I can have a look at that link and modify the code if you would prefer that.
In the wiki we explicitly say jpg or png only, although as I said I was=20
able to successfully upload a tiff image file and it was displayed.
We can maybe discuss further in the conf call to finalise on what I=20
should do.
Regards,
Adolf.
>=20
> -Michael
>=20
>> On 6 Jan 2025, at 16:21, Adolf Belka <adolf.belka(a)ipfire.org> wrote:
>>
>> - Something changed in some package in CU188 that means that the existing =
method of
>> printing the content type to the browser no longer worked.
>> - I tested it in some stand alone code and even if using text/txt for the =
content-type
>> print statement the File::Copy::copy then resulted in an Internal Serve=
r Error with
>> the same message as with the image file which was "malformed header fro=
m script
>> 'logo.cgi': Bad header:".
>> - I tested it with text, html, image and application. In all cases the err=
or message
>> about a bad header was provided.
>> - Did some searching and found an alternative way to explicitly print the =
header info
>> which is what I have used in this patch change.
>> - With this approach, in the stand alone code, I was able to get an image,=
html code or
>> text shown in the browser correctly and without any error message.
>> - I then used this new method in the logo.cgi code as submitted here and t=
ested the
>> change in my vm testbed and the image was shown in the captive portal c=
orrectly.
>> - So this change fixes the problem with the logo not being shown but I hav=
e been unable
>> to identify what changed to stop the method that worked prior to CU188 =
from working
>> any more.
>>
>> Fixes: Bug13795
>> Tested-by: Adolf Belka <adolf.belka(a)ipfire.org>
>> Signed-off-by: Adolf Belka <adolf.belka(a)ipfire.org>
>> ---
>> html/cgi-bin/captive/logo.cgi | 9 +++++----
>> 1 file changed, 5 insertions(+), 4 deletions(-)
>>
>> diff --git a/html/cgi-bin/captive/logo.cgi b/html/cgi-bin/captive/logo.cgi
>> index 8f292b171..09fe784b8 100644
>> --- a/html/cgi-bin/captive/logo.cgi
>> +++ b/html/cgi-bin/captive/logo.cgi
>> @@ -2,9 +2,9 @@
>> ##########################################################################=
#####
>> # =
#
>> # IPFire.org - A linux based firewall =
#
>> -# Copyright (C) 2016 Alexander Marx alexander.marx(a)ipfire.org =
#
>> +# Copyright (C) 2016-2024 IPFire Team <info(a)ipfire.org> =
#
>> # =
#
>> -# This program is free software you can redistribute it and/or modify =
#
>> +# This program is free software: you can redistribute it and/or modify =
#
>> # it under the terms of the GNU General Public License as published by =
#
>> # the Free Software Foundation, either version 3 of the License, or =
#
>> # (at your option) any later version. =
#
>> @@ -29,6 +29,7 @@ use File::Copy;
>>
>> require '/var/ipfire/general-functions.pl';
>>
>> +my $q =3D new CGI;
>> my $logo =3D "${General::swroot}/captive/logo.dat";
>>
>> # Send 404 if logo was not uploaded and exit
>> @@ -37,8 +38,8 @@ if (!-e $logo) {
>> exit(0);
>> }
>>
>> -print "Content-Type: application/octet-stream\n\n";
>> -
>> # Send image data
>> +print $q->header(-type=3D>"image/jpeg");
>> +binmode STDOUT;
>> File::Copy::copy $logo, \*STDOUT;
>> exit(0);
>> --=20
>> 2.47.1
>>
>=20
--=20
Sent from my laptop
--===============1120444248710799027==--