Wireshark · Ethereal-dev: Re: [ethereal-dev] Error in certificate request parsing in packet-isakmp.c

[Guy Harris <gharris@xxxxxxxxxxxx>]

On Sun, Jul 02, 2000 at 09:40:06AM +0200, Yaniv Kaul wrote:
> Attached is the Config draft from which I've taken the data.
> 1. reserved2 is 1 byte long only!
> 2. identifier is indeed in network order and should be converted.

...and length is, as I suspected, 2 bytes long:

3.2. Attribute Payload

   A new payload is defined to carry attributes as well as the type of
   transaction message.

                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     ! Next Payload  !   RESERVED    !         Payload Length        !
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     !     Type      !   RESERVED    !           Identifier          !
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     !                                                               !
     ~                           Attributes                          ~
     !                                                               !
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

so

	struct cfg_hdr {
	  guint8 next_payload;
	  guint8 reserved;
	  guint8 length[2];
	  guint8 type;
	  guint8 reserved2;
	  guint8 identifier[2];
	};

which is what I checked in (and which is in my patch), is correct.

> 3. What about cert_hdr structure? It is identical to certreq_hdr structure,
> so possibly "suffers" from the same problem.

The code I checked in (and put in the patch) changes all the headers to
use arrays of "guint8" to represent integral fields bigger than 2 bytes,
so "cert_hdr" is

	struct cert_hdr {
	  guint8	next_payload;
	  guint8	reserved;
	  guint8	length[2];
	  guint8	cert_enc;
	};