Re: [Bug 204567] New: base64 -d doesn't accept base64 output

[Jim Meyering]

In https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=204567,

James Antill wrote:
> Summary: base64 -d doesn't accept base64 output
>
> Description of problem:
>  base64 -d doesn't accept returns (which the base64 encoding should put
>  every 76 characters and at the end of the encoding).
>
> Version-Release number of selected component (if applicable):
>  coreutils-5.97-6
>
> How reproducible:
>  Always
>
> Steps to Reproduce:
> 1. echo x | base64 | base64 -d
> 2. perl -le 'print "a" x 80' | base64 | base64 -d
>
> Additional info:
>  base64 -id does work but (IMNSHO) the output of base64 and what the rfc says
> you should do should hardly be clasified as garbage. However this does present
> the obvious fix of looking for '\n' (and skipping it) on the else clause of 
> the
> ignore_garbage check.

Thanks for the report and the patch.

I suspect you know it already, but for the record,
an alternative is to filter out newlines before running base64 -d
or to encode with --wrap=0, to avoid emitting newlines altogether.
But your point is valid.

> ------- Additional Comments From address@hidden
> Created an attachment (id=135184)
> --> 
> (https://bugzilla.redhat.com/bugzilla/attachment.cgi?id=135184&action=view)
> Simple fix for base64 decoding return's
>
>  This is a simple fix, although not very efficient and allows some things
> through that shouldn't be allowed without -i. On the other hand it's so simple
> it's obviously OK to apply.

I agree that implying base64-added newlines are "garbage" is not
aesthetically pleasing :)  I'd prefer a change that adds an option to
ignore newlines (or maybe an arbitrary set of bytes) efficiently.
Of course, that would require more invasive changes.

Simon Josefsson (Cc'd) wrote both the program and much of the base64
gnulib module, so maybe he'll be interested in looking at this.