NODE f19e8621arcfour
Steve Reid <root@edmweb.com>Sun, 30 Jun 1996 15:32:48 +0800
A few questions about RC4...
I understand that RC4 is like a one-time-pad, in that a key can not be
used more than once. What about adding a different salt to the key for
each encryption? Would that be sufficent, even if the salt (but not the
rest of the key) were known to an attacker?
Is there any way to identify and weed out weak keys?
Does anyone have any sample data I can use to test an RC4 implementation?
A key and the first few bytes of the stream should be sufficent.
Thanks...
=====================================================================
| Steve Reid - SysAdmin & Pres, EDM Web (http://www.edmweb.com/) |
| Email: steve@edmweb.com Home Page: http://www.edmweb.com/steve/ |
| PGP (2048/9F317269) Fingerprint: 11C89D1CD67287E68C09EC52443F8830 |
| -- Disclaimer: JMHO, YMMV, TANSTAAFL, IANAL. -- |
===================================================================:)
NODE 531eb8c4Re: arcfour
"Mark M." <markm@voicenet.com>Mon, 1 Jul 1996 15:46:13 +0800
-----BEGIN PGP SIGNED MESSAGE-----
On Sat, 29 Jun 1996, Steve Reid wrote:
> A few questions about RC4...
>
> I understand that RC4 is like a one-time-pad, in that a key can not be
> used more than once. What about adding a different salt to the key for
> each encryption? Would that be sufficent, even if the salt (but not the
> rest of the key) were known to an attacker?
Probably.
>
> Is there any way to identify and weed out weak keys?
Keys starting with the sequence "00 00 FD", and "03 FD FC" are weak.
>
> Does anyone have any sample data I can use to test an RC4 implementation?
> A key and the first few bytes of the stream should be sufficent.
There are a few test vectors included in the original alleged-RC4 file
available on the usual crypto FTP sites.
- -- Mark
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
markm@voicenet.com | finger -l for PGP key 0xe3bf2169
http://www.voicenet.com/~markm/ | d61734f2800486ae6f79bfeb70f95348
"Freedom is the freedom to say that two plus two make four. If that
is granted, all else follows." --George Orwell, _1984_
-----BEGIN PGP SIGNATURE-----
Version: 2.6.3
Charset: noconv
iQCVAwUBMdbm/LZc+sv5siulAQHksQP9GkdqWiJ7s2ST4QF9ZwcFtFxzTk/PJskh
ReNuvXEmWFChkP0AVHJq8USFJDL4CuN4GI7d3sQpn+2HjFw+bcklCuH9zJrret2Y
mD7boKcYhzvi/abaKY9FF9/BNtC33yahrjhEIxYFx6QNTLGM9KCjBZIG7/sOAQvq
aMSYbfVhvz8=
=cgR3
-----END PGP SIGNATURE-----