From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.physik.uni-muenchen.de (mail.physik.uni-muenchen.de [192.54.42.129]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.saout.de (Postfix) with ESMTPS for ; Wed, 25 Aug 2010 11:36:40 +0200 (CEST) Received: from localhost (localhost.localdomain [127.0.0.1]) by mail.physik.uni-muenchen.de (Postfix) with ESMTP id 0E01C27DA0 for ; Wed, 25 Aug 2010 11:36:40 +0200 (CEST) Received: from mail.physik.uni-muenchen.de ([127.0.0.1]) by localhost (mail.physik.uni-muenchen.de [127.0.0.1]) (amavisd-new, port 10024) with LMTP id s10MVCKbMjde for ; Wed, 25 Aug 2010 11:36:39 +0200 (CEST) Received: from [192.168.0.100] (ppp-88-217-57-6.dynamic.mnet-online.de [88.217.57.6]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.physik.uni-muenchen.de (Postfix) with ESMTP id B6BCC27C5C for ; Wed, 25 Aug 2010 11:36:39 +0200 (CEST) From: Christoph Anton Mitterer In-Reply-To: <20100823004635.GA19317@tansi.org> References: <1280097464.3309.192.camel@fermat.scientia.net> <4C4CD361.4080000@redhat.com> <1280176686.3266.106.camel@fermat.scientia.net> <4C4E9CF4.3030308@redhat.com> <1280240110.11350.11.camel@etppc09.garching.physik.uni-muenchen.de> <4C4FED84.3040201@redhat.com> <1282338708.3231.53.camel@fermat.scientia.net> <20100821002257.GA12482@tansi.org> <1282481432.3241.44.camel@fermat.scientia.net> <20100823004635.GA19317@tansi.org> Content-Type: multipart/signed; micalg="sha1"; protocol="application/x-pkcs7-signature"; boundary="=-4Qoije4KHFMIvWG0CkHG" Date: Wed, 25 Aug 2010 11:36:38 +0200 Message-ID: <1282728998.3243.51.camel@fermat.scientia.net> Mime-Version: 1.0 Subject: Re: [dm-crypt] XTS cipher mode limitations (FAQ additions) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dm-crypt@saout.de --=-4Qoije4KHFMIvWG0CkHG Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Arno. Thanks for the other changes =3D) On Mon, 2010-08-23 at 02:46 +0200, Arno Wagner wrote: > Since I typically insist on that, I should have done this in=20 > the first place. ;-) > Diexed also for MB and kB. (No GB in there) Yeah,.. I meant of course all of them =3D) > > May I further suggest, that in all references to 2TB, we add "(=3D 2^32= * > > 512 bytes)"? > > There's always that problem that one never knows whether TB really mean= s > > TB or TiB. > Instead changed all 2TB to 2TiB.=20 I guess it could be still nice to show the "forumla"... so that people know how that 2 TiB come together... (guess many don't know that dmcrypt _always_ uses 512 byte blocks). btw: That might even qualify for its own FAQ entry,... that it uses always 512byte blocks, and that e.g. the number in the payload offset from luksDump are also blocks. > Well, if it comes up again, I can look at it. I will=20 > however not start to distribute my own FUD and I am=20 > not a good enough cryptographer for a really thorough > analysis of the issue. I am willing to read a paper on > it if somebody else provides the link ;-) Once you should add it... don't forget (which I just realised recently ^^) that it's about the written data in blocks,... not just the written data itself, at least if I understand it correctly. So say we _would_ have a hard limit on 1TB, and I'd just write 1 bit, I'd still have "used up" 512 bytes from my safety buffer, before having to re-encode, right? btw: Milan, do you know about any paper dealing with that issue? Cheers, Chris. --=-4Qoije4KHFMIvWG0CkHG Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIKnjCCBUsw ggQzoAMCAQICAimIMA0GCSqGSIb3DQEBBQUAMDYxCzAJBgNVBAYTAkRFMRMwEQYDVQQKEwpHZXJt YW5HcmlkMRIwEAYDVQQDEwlHcmlkS2EtQ0EwHhcNMTAwMjAyMTUzODQyWhcNMTEwMzA0MTUzODQy WjBTMQswCQYDVQQGEwJERTETMBEGA1UEChMKR2VybWFuR3JpZDEMMAoGA1UECxMDTE1VMSEwHwYD VQQDExhDaHJpc3RvcGggQW50b24gTWl0dGVyZXIwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEK AoIBAQDB2Qx+2tMdrECcbeWidmr8n6M307ZhmRkijL2L4fSfD0tq5dgd6/upKPl/yZszPA9uRnCa GJBX+AA5+3GXG9sL/zE88t7c1LdD1rJcO23OO3Z35bWj3zMzhiXFq+rlgqLTixeS4YjEJ45J58BQ nvdZW9enAwtF+loQguehemyOv7GTpsbTBzwBcrM2YOdX1DdFBdspvjv/zGbgA8qcVNqKPZ/j1Om0 nLwDK/q+5yUO4v1m50Y6ApgmGuH9+xCBwKiBhjwR575utKfIBoAYAAZ4GAO0RWB6tsXrLV6OTSj0 Cvx97+6FbI7btHtLDz62r3KJKHt3YVhLufPPurr6moKfAgMBAAGjggJEMIICQDAMBgNVHRMBAf8E AjAAMA4GA1UdDwEB/wQEAwIE8DAdBgNVHQ4EFgQU6mpOncVXSCbY9n7zHlYWcvVMAGcwXgYDVR0j BFcwVYAUxnXJKKzRC/w8/7m1HtNfO4BiEjShOqQ4MDYxCzAJBgNVBAYTAkRFMRMwEQYDVQQKEwpH ZXJtYW5HcmlkMRIwEAYDVQQDEwlHcmlkS2EtQ0GCAQAwOgYDVR0RBDMwMYEvY2hyaXN0b3BoLmFu dG9uLm1pdHRlcmVyQHBoeXNpay51bmktbXVlbmNoZW4uZGUwHwYDVR0SBBgwFoEUZ3JpZGthLWNh QGl3ci5memsuZGUwNQYDVR0fBC4wLDAqoCigJoYkaHR0cDovL2dyaWQuZnprLmRlL2NhL2dyaWRr YS1jcmwuZGVyMBoGA1UdIAQTMBEwDwYNKwYBBAGUNqssAQEBBTARBglghkgBhvhCAQEEBAMCBaAw TgYJYIZIAYb4QgENBEEWP0NlcnRpZmljYXRlIGlzc3VlZCB1bmRlciBDUC9DUFMgdi4gMS41IGF0 IGh0dHA6Ly9ncmlkLmZ6ay5kZS9jYTAkBglghkgBhvhCAQIEFxYVaHR0cDovL2dyaWQuZnprLmRl L2NhMDMGCWCGSAGG+EIBCAQmFiRodHRwOi8vZ3JpZC5memsuZGUvY2EvZ3JpZGthLWNwcy5wZGYw MwYJYIZIAYb4QgEDBCYWJGh0dHA6Ly9ncmlkLmZ6ay5kZS9jYS9ncmlka2EtY3JsLmRlcjANBgkq hkiG9w0BAQUFAAOCAQEAx4bax1WiHpkiGAtCHawUp7+4CJfRDnrRv5B477+h8ILTY0mzHNumC5Ru +RpnfUi4zcbFA8uEnKifTRFeZH6kflC+xhLfg2kiN00Qqy0+IvYcTYo/ZGUhKLV3Q22R8tKpTjuY o4svWK0PQoSgcrVccGp7ZzHknKAS3dZjQTSg5JXfeLKrh0JZVRQ2S3CaOGBzTb8hXPSP1iAJ3klw hAApYZux9NQmBlEW7DeK5DwKiny+dbuipMrXwASz4tgnI/s9wwEml8tGXjnQDbyz4uRMa2Xyrzg4 iq+vWHLUsRGC1Api5FsBfBVTQPqRE1isyk8rPYcBoDk7dirgswhHwcK97TCCBUswggQzoAMCAQIC AimIMA0GCSqGSIb3DQEBBQUAMDYxCzAJBgNVBAYTAkRFMRMwEQYDVQQKEwpHZXJtYW5HcmlkMRIw EAYDVQQDEwlHcmlkS2EtQ0EwHhcNMTAwMjAyMTUzODQyWhcNMTEwMzA0MTUzODQyWjBTMQswCQYD VQQGEwJERTETMBEGA1UEChMKR2VybWFuR3JpZDEMMAoGA1UECxMDTE1VMSEwHwYDVQQDExhDaHJp c3RvcGggQW50b24gTWl0dGVyZXIwggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDB2Qx+ 2tMdrECcbeWidmr8n6M307ZhmRkijL2L4fSfD0tq5dgd6/upKPl/yZszPA9uRnCaGJBX+AA5+3GX G9sL/zE88t7c1LdD1rJcO23OO3Z35bWj3zMzhiXFq+rlgqLTixeS4YjEJ45J58BQnvdZW9enAwtF +loQguehemyOv7GTpsbTBzwBcrM2YOdX1DdFBdspvjv/zGbgA8qcVNqKPZ/j1Om0nLwDK/q+5yUO 4v1m50Y6ApgmGuH9+xCBwKiBhjwR575utKfIBoAYAAZ4GAO0RWB6tsXrLV6OTSj0Cvx97+6FbI7b tHtLDz62r3KJKHt3YVhLufPPurr6moKfAgMBAAGjggJEMIICQDAMBgNVHRMBAf8EAjAAMA4GA1Ud DwEB/wQEAwIE8DAdBgNVHQ4EFgQU6mpOncVXSCbY9n7zHlYWcvVMAGcwXgYDVR0jBFcwVYAUxnXJ KKzRC/w8/7m1HtNfO4BiEjShOqQ4MDYxCzAJBgNVBAYTAkRFMRMwEQYDVQQKEwpHZXJtYW5Hcmlk MRIwEAYDVQQDEwlHcmlkS2EtQ0GCAQAwOgYDVR0RBDMwMYEvY2hyaXN0b3BoLmFudG9uLm1pdHRl cmVyQHBoeXNpay51bmktbXVlbmNoZW4uZGUwHwYDVR0SBBgwFoEUZ3JpZGthLWNhQGl3ci5memsu ZGUwNQYDVR0fBC4wLDAqoCigJoYkaHR0cDovL2dyaWQuZnprLmRlL2NhL2dyaWRrYS1jcmwuZGVy MBoGA1UdIAQTMBEwDwYNKwYBBAGUNqssAQEBBTARBglghkgBhvhCAQEEBAMCBaAwTgYJYIZIAYb4 QgENBEEWP0NlcnRpZmljYXRlIGlzc3VlZCB1bmRlciBDUC9DUFMgdi4gMS41IGF0IGh0dHA6Ly9n cmlkLmZ6ay5kZS9jYTAkBglghkgBhvhCAQIEFxYVaHR0cDovL2dyaWQuZnprLmRlL2NhMDMGCWCG SAGG+EIBCAQmFiRodHRwOi8vZ3JpZC5memsuZGUvY2EvZ3JpZGthLWNwcy5wZGYwMwYJYIZIAYb4 QgEDBCYWJGh0dHA6Ly9ncmlkLmZ6ay5kZS9jYS9ncmlka2EtY3JsLmRlcjANBgkqhkiG9w0BAQUF AAOCAQEAx4bax1WiHpkiGAtCHawUp7+4CJfRDnrRv5B477+h8ILTY0mzHNumC5Ru+RpnfUi4zcbF A8uEnKifTRFeZH6kflC+xhLfg2kiN00Qqy0+IvYcTYo/ZGUhKLV3Q22R8tKpTjuYo4svWK0PQoSg crVccGp7ZzHknKAS3dZjQTSg5JXfeLKrh0JZVRQ2S3CaOGBzTb8hXPSP1iAJ3klwhAApYZux9NQm BlEW7DeK5DwKiny+dbuipMrXwASz4tgnI/s9wwEml8tGXjnQDbyz4uRMa2Xyrzg4iq+vWHLUsRGC 1Api5FsBfBVTQPqRE1isyk8rPYcBoDk7dirgswhHwcK97TGCAl8wggJbAgEBMDwwNjELMAkGA1UE BhMCREUxEzARBgNVBAoTCkdlcm1hbkdyaWQxEjAQBgNVBAMTCUdyaWRLYS1DQQICKYgwCQYFKw4D AhoFAKCB+TAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0xMDA4MjUw OTM2MzhaMCMGCSqGSIb3DQEJBDEWBBRW3dHGSekPbADgpZZ+MpVdeUWP5DBLBgkrBgEEAYI3EAQx PjA8MDYxCzAJBgNVBAYTAkRFMRMwEQYDVQQKEwpHZXJtYW5HcmlkMRIwEAYDVQQDEwlHcmlkS2Et Q0ECAimIME0GCyqGSIb3DQEJEAILMT6gPDA2MQswCQYDVQQGEwJERTETMBEGA1UEChMKR2VybWFu R3JpZDESMBAGA1UEAxMJR3JpZEthLUNBAgIpiDANBgkqhkiG9w0BAQEFAASCAQAj2XER8Eq/OlRy LKsWTnnRuui0AVXLygYLwlst/DHvp6w5HYBR4wJVIjT2lPpaaq5rZcNbqPYJwMdvhSM9WgpEkgBZ vfgdZ94CJMJAaG1n7suQLGbe9ZnQ4L47BETLH8PpxHn9+6gYgvz6LWL9AqdC7/Ng1Pm76nl6vzIG L/+d8DlE/ZpI1A3rWaY4lOynbN50L8jVvSM7pFYk4N4DXFYIYRFBI6Li132AZgs5ycnR6QS1WoWL Bzl0z6jeib7fSx5+tSQr1Ehbaz+bpjdS6tducJpqLY93chazniqbkjeICLGrttdPhFMXS3RTj5Us 2HhgR2UpCJblWWubbXm98r+/AAAAAAAA --=-4Qoije4KHFMIvWG0CkHG--