Re: [Sks-devel] Re: zero-length MPIs (was: Re: mpi error with check-trustdb in 1.4.2 - resolved)

[Peter Palfrader]

On Thu, 11 Aug 2005, Jason Harris wrote:

> On Thu, Aug 11, 2005 at 09:54:59PM +0200, Peter Palfrader wrote:
> > On Thu, 11 Aug 2005, Jason Harris wrote:
> > > Fetching them from keyserver.kjsl.com is now possible with gnupg-1.4.2.
> > > To patch pks, add this to the middle of decode_mpi() (in pgputil.c):
> > > 
> > >   /* skip packets with 0-length MPIs for GPG's benefit (gnupg-1.4.2) */
> > >   if (mpi->nbits == 0) {
> > >     return (0);
> > >   }
> > 
> > can we do that in SKS too?  please!
> 
> Try the patch below.

Ok, that seems to work great.

Yaron, will you accept this patch?   I wonder what the effects on
syncing is.

Can we also have one that filters most 'buffer shorter than subpacket'
problems?  Such keys have become a real problem since also popular keys
are affected,  For instance CA57AD7C (PGP Global Directory Verification
Key).

> ===================================================================
> RCS file: parsePGP.ml,v
> retrieving revision 1.1
> diff -u -r1.1 parsePGP.ml
> --- parsePGP.ml       2005/08/12 00:03:16     1.1
> +++ parsePGP.ml       2005/08/12 00:03:54
> @@ -23,6 +23,7 @@
>  open Printf
>  
>  exception Overlong_mpi
> +exception Zerolen_mpi
>  exception Partial_body_length of int
>  
>  (********************************************************)
> @@ -109,6 +110,7 @@
>    try
>      let byte2 = cin#read_byte in
>      let length = (byte1 lsl 8) + byte2 in
> +    if length <= 0 then raise Zerolen_mpi;
>      let data = cin#read_string 
>                ((length + 7)/8)
>      in
> 


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