Re: ldap cert retrieval and pem encoding

[Ulf Stegemann <ulf@zeitform.de>]

Arne Jørgensen <arne@arnested.dk> wrote:

> I have implemented the above strategy.

Great!

> I had no way to test it (except that it still works with DER encoded
> certificates).
>
> The attached patch also includes the patch for LDAP handling in XEmacs
> (from some weeks ago).

Okay, I had to change two things (s.b.) and now it works very well ... for
both PEM and DER encoded certs.

[...]

> Index: lisp/smime.el
> ===================================================================
> RCS file: /usr/local/cvsroot/gnus/lisp/smime.el,v
> retrieving revision 7.11
> diff -u -p -r7.11 smime.el
> --- lisp/smime.el	17 May 2005 08:02:16 -0000	7.11
> +++ lisp/smime.el	31 May 2005 09:17:51 -0000
> @@ -578,9 +578,20 @@ A string or a list of strings is returne
>  				       host '("userCertificate") nil))
>  	(retbuf (generate-new-buffer (format "*certificate for %s*" mail)))
>  	cert)
> -    (if (> (length ldapresult) 1)
> +    (if (>= (length ldapresult) 1)
>  	(with-current-buffer retbuf
> -	  (setq cert (base64-encode-string (nth 1 (car (nth 1 ldapresult))) t))
> +	  ;; Certificates on LDAP servers _should_ be in DER format,
> +	  ;; but there are some servers out there that distributes the
> +	  ;; certificates in PEM format (with or without
> +	  ;; header/footer) so we try to handle them anyway.
> +	  (if (or (string= (substring (cadaar ldapresult) 0 27)
> +			   "-----BEGIN CERTIFICATE-----")
> +		  (condition-case nil
> +		      (base64-decode-string (cadaar ldapresult))
> +		    (error nil)))
> +	      (setq cert
> +		    (replace-regexp-in-string "\\(\n\||\r\\|-----BEGIN CERTIFICATE-----\\|-----END CERTIFICATE-----\\)" "" (cadaar ldapresult) t))

It seems that replace-regexp-in-string is not known to xemacs but only to
emacs.  Furthermore, there's a typo in the regex ('\||\r' instead of '\\|\r').
The following replacement does the job here (XEmacs 21.4 (patch 17)):

  (replace-in-string 
   (cadaar ldapresult) 
   "\\(\n\\|\r\\|-----BEGIN CERTIFICATE-----\\|-----END CERTIFICATE-----\\)"
   "" t))

> +	    (setq cert (base64-encode-string (cadaar ldapresult) t)))
>  	  (insert "-----BEGIN CERTIFICATE-----\n")
>  	  (let ((i 0) (len (length cert)))
>  	    (while (> (- len 64) i)


Ulf