detect change of remote page

[will taubin]

hi everyone,

i have some links on my site, i need to be absolutely sure that the
html has not been modified, even one character. i would rather not
rely on http headers, just the html (so it is not dependant on the
webserver). should i make a database to actually mirror the page, and
then check against my copy? any better ideas? :)

thanks

[Geoff Berrow]

Re: detect change of remote page

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Hash: SHA1

I noticed that Message-ID:
<aa5d813d.03112 01518.212dda20@ posting.google. com> from will taubin
contained the following:
[color=blue]
>i have some links on my site, i need to be absolutely sure that the
>html has not been modified, even one character. i would rather not
>rely on http headers, just the html (so it is not dependant on the
>webserver). should i make a database to actually mirror the page,
>and then check against my copy? any better ideas? :)[/color]

Don't know how you would do it, but a hash of the page may be
sufficient? A bit like PGP sig?

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Version: PGPfreeware 6.5.8 for non-commercial use <http://www.pgp.com>

iQA/AwUBP71VCmUsPVs ZRo4gEQK+cwCfUo GD8tF8SKmidE1E6 mjRtO0cJJ4An2Vd
x0Gv5k/DriaFBcxM7563Fe PJ
=2nYp
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--
Geoff Berrow (put thecat out to email)
It's only Usenet, no one dies.
My opinions, not the committee's, mine.
Simple RFDs http://www.ckdog.co.uk/rfdmaker/

[André Næss]

Re: detect change of remote page

will taubin:
[color=blue]
> hi everyone,
>
> i have some links on my site, i need to be absolutely sure that the
> html has not been modified, even one character. i would rather not
> rely on http headers, just the html (so it is not dependant on the
> webserver). should i make a database to actually mirror the page, and
> then check against my copy? any better ideas? :)[/color]

Checksum the file, and store the checksum locally. Then you can verify the
file against this checksum when you access it. md5() is ok for this
purpose.

André Næss

[will taubin]

Re: detect change of remote page

André Næss <andrena.spamre allysucks@ifi.u io.no> wrote in message news:<bpjkk3$h8 q$1@maud.ifi.ui o.no>...[color=blue]
> will taubin:
>[color=green]
> > hi everyone,
> >
> > i have some links on my site, i need to be absolutely sure that the
> > html has not been modified, even one character. i would rather not
> > rely on http headers, just the html (so it is not dependant on the
> > webserver). should i make a database to actually mirror the page, and
> > then check against my copy? any better ideas? :)[/color]
>
> Checksum the file, and store the checksum locally. Then you can verify the
> file against this checksum when you access it. md5() is ok for this
> purpose.
>
> André Næss[/color]

thanks, but if i generate a checksum, then later download the file
again to compare the checksums, will the timestamps affect the new
checksum? or is it generated only based on the content of the file?

[Irnis Haliullin]

Re: detect change of remote page

> Checksum the file, and store the checksum locally. Then you can verify the[color=blue]
> file against this checksum when you access it. md5() is ok for this
> purpose.
>[/color]
If you are using Windows, the Advanced CheckSum Verifier from
http://www.irnis.net is just for you :)

[André Næss]

Re: detect change of remote page

will taubin:
[color=blue]
> André Næss <andrena.spamre allysucks@ifi.u io.no> wrote in message
> news:<bpjkk3$h8 q$1@maud.ifi.ui o.no>...[color=green]
>> will taubin:
>>[color=darkred]
>> > hi everyone,
>> >
>> > i have some links on my site, i need to be absolutely sure that the
>> > html has not been modified, even one character. i would rather not
>> > rely on http headers, just the html (so it is not dependant on the
>> > webserver). should i make a database to actually mirror the page, and
>> > then check against my copy? any better ideas? :)[/color]
>>
>> Checksum the file, and store the checksum locally. Then you can verify
>> the file against this checksum when you access it. md5() is ok for this
>> purpose.
>>
>> André Næss[/color]
>
> thanks, but if i generate a checksum, then later download the file
> again to compare the checksums, will the timestamps affect the new
> checksum? or is it generated only based on the content of the file?[/color]

It's generated based on whatever you input, so as long as you only input the
contents, and this doesn't change, you're ok.

André Næss