Received: from hoffman.proper.com (localhost [127.0.0.1]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OLHWVn094338 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 24 Jun 2010 14:17:32 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) Received: (from majordom@localhost) by hoffman.proper.com (8.14.4/8.13.5/Submit) id o5OLHWpo094337; Thu, 24 Jun 2010 14:17:32 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) X-Authentication-Warning: hoffman.proper.com: majordom set sender to owner-ietf-openpgp@mail.imc.org using -f Received: from mail-ew0-f43.google.com (mail-ew0-f43.google.com [209.85.215.43]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OLHUJs094332 for ; Thu, 24 Jun 2010 14:17:31 -0700 (MST) (envelope-from nagydani@epointsystem.org) Received: by ewy9 with SMTP id 9so571247ewy.16 for ; Thu, 24 Jun 2010 14:17:29 -0700 (PDT) Received: by 10.87.30.35 with SMTP id h35mr6145278fgj.73.1277414249305; Thu, 24 Jun 2010 14:17:29 -0700 (PDT) Received: from [10.77.0.151] (78-131-55-134.static.hdsnet.hu [78.131.55.134]) by mx.google.com with ESMTPS id 3sm15999316fge.5.2010.06.24.14.17.28 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 24 Jun 2010 14:17:28 -0700 (PDT) Message-ID: <4C23CB67.3000703@epointsystem.org> Date: Thu, 24 Jun 2010 23:17:27 +0200 From: "Daniel A. Nagy" User-Agent: Thunderbird 2.0.0.24 (X11/20100317) MIME-Version: 1.0 To: Brian Lewis CC: ietf-openpgp@imc.org Subject: Re: ElGamal, EME-PKCS1-v1_5 References: <20100624173119.GJ25604@brian.internal.monetra.com> In-Reply-To: <20100624173119.GJ25604@brian.internal.monetra.com> X-Enigmail-Version: 0.95.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enig292AE4AE63723EB91C7C45D9" Sender: owner-ietf-openpgp@mail.imc.org Precedence: bulk List-Archive: List-Unsubscribe: List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig292AE4AE63723EB91C7C45D9 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hello, Brian Lewis wrote: > So I need m =3D EME-PKCS1-v1_5(...). According to > http://tools.ietf.org/html/rfc3447#section-7.2.1, PS is k - mLen > - 3 random nonzero bytes, where k is the length of RSA n in bytes. But = I > don't have RSA n. I have ElGamal p, g, and y. >=20 > In EME-PKCS1-v1_5, what is k if I'm using ElGamal? You should use the length of ElGamal p. --=20 Daniel --------------enig292AE4AE63723EB91C7C45D9 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEAREIAAYFAkwjy2cACgkQoeH/BzqmYjg4IQCgpw5+KIAXiDH97ZZaaxhyis/Z dPIAn3OwEwKusanHea7oOhwLldg2B8dk =RNIV -----END PGP SIGNATURE----- --------------enig292AE4AE63723EB91C7C45D9-- Received: from hoffman.proper.com (localhost [127.0.0.1]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OK8tvi090410 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 24 Jun 2010 13:08:55 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) Received: (from majordom@localhost) by hoffman.proper.com (8.14.4/8.13.5/Submit) id o5OK8tU6090409; Thu, 24 Jun 2010 13:08:55 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) X-Authentication-Warning: hoffman.proper.com: majordom set sender to owner-ietf-openpgp@mail.imc.org using -f Received: from mail.mainstreetsoftworks.com (mail.mainstreetsoftworks.com [216.155.111.4]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OK8sW1090402 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO) for ; Thu, 24 Jun 2010 13:08:55 -0700 (MST) (envelope-from brian@monetra.com) Received: from localhost (shop.monetra.com [216.155.101.90]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.mainstreetsoftworks.com (Postfix) with ESMTPSA id A9E1584402F; Thu, 24 Jun 2010 16:08:47 -0400 (EDT) Date: Thu, 24 Jun 2010 16:10:26 -0400 From: Brian Lewis To: Marko Kreen Cc: ietf-openpgp@imc.org Subject: Re: ElGamal, EME-PKCS1-v1_5 Message-ID: <20100624201026.GL25604@brian.internal.monetra.com> References: <20100624173119.GJ25604@brian.internal.monetra.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-monetra-com-MailScanner-Information: Please contact the ISP for more information X-monetra-com-MailScanner-ID: A9E1584402F.A3E16 X-monetra-com-MailScanner: Found to be clean X-monetra-com-MailScanner-SpamCheck: not spam, SpamAssassin (not cached, score=-8.899, required 4.7, ALL_TRUSTED -1.80, BAYES_00 -2.60, USER_IN_WHITELIST -4.50) X-monetra-com-MailScanner-From: brian@monetra.com X-Spam-Status: No Sender: owner-ietf-openpgp@mail.imc.org Precedence: bulk List-Archive: List-Unsubscribe: List-ID: On Thursday, 24.06.10 at 22:52, Marko Kreen wrote: > On 6/24/10, Brian Lewis wrote: > > I'm trying to generate a tag 1 (public-key encrypted session key) > > packet. > > > > I'm using ElGamal, so the algorithm-specific fields are, according to > > http://tools.ietf.org/html/rfc4880#section-5.1, > > MPI g**k mod p > > MPI m * y**k mod p > > > > So I need m = EME-PKCS1-v1_5(...). According to > > http://tools.ietf.org/html/rfc3447#section-7.2.1, PS is k - mLen > > - 3 random nonzero bytes, where k is the length of RSA n in bytes. But I > > don't have RSA n. I have ElGamal p, g, and y. > > > > In EME-PKCS1-v1_5, what is k if I'm using ElGamal? > > mod p ~ mod n I don't understand. Could you elaborate? Received: from hoffman.proper.com (localhost [127.0.0.1]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OJqdAk089528 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 24 Jun 2010 12:52:39 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) Received: (from majordom@localhost) by hoffman.proper.com (8.14.4/8.13.5/Submit) id o5OJqdAY089527; Thu, 24 Jun 2010 12:52:39 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) X-Authentication-Warning: hoffman.proper.com: majordom set sender to owner-ietf-openpgp@mail.imc.org using -f Received: from mail-ww0-f43.google.com (mail-ww0-f43.google.com [74.125.82.43]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OJqbjC089521 for ; Thu, 24 Jun 2010 12:52:38 -0700 (MST) (envelope-from markokr@gmail.com) Received: by wwd20 with SMTP id 20so106574wwd.16 for ; Thu, 24 Jun 2010 12:52:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=xGI9otJ2ud5zIZCBqoZqZIuimrt/rALrSE1J7JEU3Jw=; b=N7ITyQTPPLV2hQj12RpnSw8AwK3IwwkO9QEwKVUy9B8ECoQPuLjzlx/Wv9qMeCJdEf KzAkKhr3oAonwKqDnMzCiNsqcn3MbGZKxhlE0xKXahpuGyFbZDBVpxhmkuuXL6zJAacy aLeURW9eQw8KQDNlx/eiSHVUR1Xe5N+zQRKFo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=V4bPWg3hhYng9fpszYG1lwNQYDsaG1OceqCw5xnt4cHUyA2DbHAec6xLDciEZsXMJh 9ArbXOEkrXfPLGZjPQzVeiaIL3EoxItpeX1yuUUWiLVOpIZokO3huMequs2KmvoiLj3e pi4QHuKrIpS45x9GRh9WH9GA/3J0TCFHMmB/o= MIME-Version: 1.0 Received: by 10.216.160.132 with SMTP id u4mr7319871wek.19.1277409156055; Thu, 24 Jun 2010 12:52:36 -0700 (PDT) Received: by 10.216.175.69 with HTTP; Thu, 24 Jun 2010 12:52:35 -0700 (PDT) In-Reply-To: <20100624173119.GJ25604@brian.internal.monetra.com> References: <20100624173119.GJ25604@brian.internal.monetra.com> Date: Thu, 24 Jun 2010 22:52:35 +0300 Message-ID: Subject: Re: ElGamal, EME-PKCS1-v1_5 From: Marko Kreen To: Brian Lewis Cc: ietf-openpgp@imc.org Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-ietf-openpgp@mail.imc.org Precedence: bulk List-Archive: List-Unsubscribe: List-ID: On 6/24/10, Brian Lewis wrote: > I'm trying to generate a tag 1 (public-key encrypted session key) > packet. > > I'm using ElGamal, so the algorithm-specific fields are, according to > http://tools.ietf.org/html/rfc4880#section-5.1, > MPI g**k mod p > MPI m * y**k mod p > > So I need m = EME-PKCS1-v1_5(...). According to > http://tools.ietf.org/html/rfc3447#section-7.2.1, PS is k - mLen > - 3 random nonzero bytes, where k is the length of RSA n in bytes. But I > don't have RSA n. I have ElGamal p, g, and y. > > In EME-PKCS1-v1_5, what is k if I'm using ElGamal? mod p ~ mod n -- marko Received: from hoffman.proper.com (localhost [127.0.0.1]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OHTlVe080697 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 24 Jun 2010 10:29:47 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) Received: (from majordom@localhost) by hoffman.proper.com (8.14.4/8.13.5/Submit) id o5OHTlv4080696; Thu, 24 Jun 2010 10:29:47 -0700 (MST) (envelope-from owner-ietf-openpgp@mail.imc.org) X-Authentication-Warning: hoffman.proper.com: majordom set sender to owner-ietf-openpgp@mail.imc.org using -f Received: from mail.mainstreetsoftworks.com (mail.mainstreetsoftworks.com [216.155.111.4]) by hoffman.proper.com (8.14.4/8.14.3) with ESMTP id o5OHTklN080684 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO) for ; Thu, 24 Jun 2010 10:29:47 -0700 (MST) (envelope-from brian@monetra.com) Received: from localhost (shop.monetra.com [216.155.101.90]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mail.mainstreetsoftworks.com (Postfix) with ESMTPSA id 1DFB484402F for ; Thu, 24 Jun 2010 13:29:40 -0400 (EDT) Date: Thu, 24 Jun 2010 13:31:19 -0400 From: Brian Lewis To: ietf-openpgp@imc.org Subject: ElGamal, EME-PKCS1-v1_5 Message-ID: <20100624173119.GJ25604@brian.internal.monetra.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-monetra-com-MailScanner-Information: Please contact the ISP for more information X-monetra-com-MailScanner-ID: 1DFB484402F.A2D5F X-monetra-com-MailScanner: Found to be clean X-monetra-com-MailScanner-SpamCheck: not spam, SpamAssassin (not cached, score=-8.899, required 4.7, ALL_TRUSTED -1.80, BAYES_00 -2.60, USER_IN_WHITELIST -4.50) X-monetra-com-MailScanner-From: brian@monetra.com X-Spam-Status: No Sender: owner-ietf-openpgp@mail.imc.org Precedence: bulk List-Archive: List-Unsubscribe: List-ID: I'm trying to generate a tag 1 (public-key encrypted session key) packet. I'm using ElGamal, so the algorithm-specific fields are, according to http://tools.ietf.org/html/rfc4880#section-5.1, MPI g**k mod p MPI m * y**k mod p So I need m = EME-PKCS1-v1_5(...). According to http://tools.ietf.org/html/rfc3447#section-7.2.1, PS is k - mLen - 3 random nonzero bytes, where k is the length of RSA n in bytes. But I don't have RSA n. I have ElGamal p, g, and y. In EME-PKCS1-v1_5, what is k if I'm using ElGamal? Thank you.