Re: IDN deployed in Sweden

[Patrik Fältström <patrik@xn--fltstrm-5wa1o.se>]

On 2003-11-06, at 15.07, Steven M. Bellovin wrote:

> In message 
> <F298286C-1038-11D8-82FB-000A959CF516@xn--fltstrm-5wa1o.se>, =?ISO-8
> 859-1?Q?Patrik_F=E4ltstr=F6m?= writes:
> > Now you know...
> >
> >    Patrik <patrik@fältström.se>
> >
> > P.S. Here above you see how difficult it will be to copy-and-paste
> > email addresses, because I presume your email client is not doing "the
> > right thing" and neither is the clipboard)
> Here's the bounce message I received from Postfix when I tried the
> cut-and-paste.

Exactly. What happens is that your "IDN-unaware" client tries to send 
to that email domain, it converts the domain name "fältström.se" into 
"Quoted-Printable" which is used in some headers according to the MIME 
standard. I.e. fältström.se -> =?iso-8859-1?Q?f=E4ltstr=F6m?=.se

IDNA say the conversion is to be fältström.se -> xn--fltstrm-5wa1o.se, 
so clients which doesn't follow this is simply doing the wrong thing.

Now, if we go back to another interesting discussion point, what would 
have happened if your client just tried to look up the 
=?iso-8859-1?Q?f=E4ltstr=F6m?=.se domain and the TLD operator of "se" 
had a wildcard in the "se" zone?

zx81>dig '=?iso-8859-1?Q?f=E4ltstr=F6m?=.se' any

; <<>> DiG 9.2.2 <<>> =?iso-8859-1?Q?f=E4ltstr=F6m?=.se any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 63028
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;=?iso-8859-1?Q?f=E4ltstr=F6m?=.se. IN  ANY

;; AUTHORITY SECTION:
se.                     10800   IN      SOA     
catcher-in-the-rye.nic-se.se. registry.nic-se.se. 2003110612 7200 3600 
2419200 86400

;; Query time: 47 msec
;; SERVER: 195.66.31.71#53(195.66.31.71)
;; WHEN: Thu Nov  6 15:13:42 2003
;; MSG SIZE  rcvd: 124

zx81>dig '=?iso-8859-1?Q?f=E4ltstr=F6m?=.museum' any

; <<>> DiG 9.2.2 <<>> =?iso-8859-1?Q?f=E4ltstr=F6m?=.museum any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13729
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;=?iso-8859-1?Q?f=E4ltstr=F6m?=.museum. IN ANY

;; ANSWER SECTION:
=?iso-8859-1?Q?f=E4ltstr=F6m?=.museum. 180 IN A 195.7.77.20

;; AUTHORITY SECTION:
museum.                 86400   IN      NS      ns1.getty.edu.
museum.                 86400   IN      NS      ns-ext.vix.com.
museum.                 86400   IN      NS      ns.icann.org.
museum.                 86400   IN      NS      nic.icom.org.
museum.                 86400   IN      NS      nic.museum.

;; ADDITIONAL SECTION:
ns1.getty.edu.          172800  IN      A       192.215.101.23
ns-ext.vix.com.         128941  IN      A       204.152.184.64
ns.icann.org.           129683  IN      A       192.0.34.126
nic.icom.org.           172800  IN      A       195.7.65.253
nic.museum.             172800  IN      A       130.242.24.5

;; Query time: 127 msec
;; SERVER: 195.66.31.71#53(195.66.31.71)
;; WHEN: Thu Nov  6 15:13:50 2003
;; MSG SIZE  rcvd: 310


...

     paf

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> <patrik@=?iso-8859-1?Q?f=E4ltstr=F6m?=.se>: bad host/domain syntax:
>     "=?iso-8859-1?Q?f=E4ltstr=F6m?=.se"
>
>
> 		--Steve Bellovin, http://www.research.att.com/~smb