* [dm-crypt] Feitian PKI donation to dm-crypt projetc
@ 2010-11-03 18:26 Jean-Michel Pouré - GOOZE
2010-11-03 20:29 ` Christoph Anton Mitterer
` (2 more replies)
0 siblings, 3 replies; 16+ messages in thread
From: Jean-Michel Pouré - GOOZE @ 2010-11-03 18:26 UTC (permalink / raw)
To: dm-crypt
Dear friends,
We would be happy to offer three Feitian PKI smartcards to the dm-crypt
project. Free Software developer can register here:
http://gooze.eu/feitian-pki-free-software-developer-card
Also, we are currently writing a HOWTO to publish on GOOZE.
Is there a way to enable dm-crypt using opensc-pkcs11.so on startup?
The idea is to have a complete encrypted system on boot.
This probably involves creating an initrd with OpenSSL and OpenSC
included. Did anyone succeed in this?
Kind regards,
Jean-Michel POURE
--
Jean-Michel Pouré - Gooze - http://www.gooze.eu
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 18:26 [dm-crypt] Feitian PKI donation to dm-crypt projetc Jean-Michel Pouré - GOOZE @ 2010-11-03 20:29 ` Christoph Anton Mitterer 2010-11-03 22:34 ` Arno Wagner 2010-11-04 8:52 ` Milan Broz 2 siblings, 0 replies; 16+ messages in thread From: Christoph Anton Mitterer @ 2010-11-03 20:29 UTC (permalink / raw) To: jmpoure; +Cc: dm-crypt [-- Attachment #1: Type: text/plain, Size: 489 bytes --] On Wed, 2010-11-03 at 19:26 +0100, Jean-Michel Pouré - GOOZE wrote: > Is there a way to enable dm-crypt using opensc-pkcs11.so on startup? > The idea is to have a complete encrypted system on boot. > > This probably involves creating an initrd with OpenSSL and OpenSC > included. Did anyone succeed in this? e.g. Debian includes some very basic scripts to use those two, although they're dis-functional in several cases, you can use them as starting point. Cheers, Chris. [-- Attachment #2: smime.p7s --] [-- Type: application/x-pkcs7-signature, Size: 3387 bytes --] ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 18:26 [dm-crypt] Feitian PKI donation to dm-crypt projetc Jean-Michel Pouré - GOOZE 2010-11-03 20:29 ` Christoph Anton Mitterer @ 2010-11-03 22:34 ` Arno Wagner 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE ` (2 more replies) 2010-11-04 8:52 ` Milan Broz 2 siblings, 3 replies; 16+ messages in thread From: Arno Wagner @ 2010-11-03 22:34 UTC (permalink / raw) To: dm-crypt On Wed, Nov 03, 2010 at 07:26:12PM +0100, Jean-Michel Pour? - GOOZE wrote: > Dear friends, > > We would be happy to offer three Feitian PKI smartcards to the dm-crypt > project. Free Software developer can register here: > http://gooze.eu/feitian-pki-free-software-developer-card > > Also, we are currently writing a HOWTO to publish on GOOZE. > > Is there a way to enable dm-crypt using opensc-pkcs11.so on startup? > The idea is to have a complete encrypted system on boot. > > This probably involves creating an initrd with OpenSSL and OpenSC > included. Did anyone succeed in this? Having a not completely encrypted initrd and kernel does not qualify as "completely encrypted system on boot". Anyways, this is not really in the dm-crypt/LUKS focus, although some people go the way of having an initrd that does set-up an encrypted root. They typically find it painful and difficult to set-up, but it is possible. The main dm-crypt/LUKS focus is encrypted partitions in an otherwise not encrypted system. The only interface for integrating external keys is by reading them from file or stdin and that is by desing to keep things simple. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 22:34 ` Arno Wagner @ 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE 2010-11-05 13:48 ` Christoph Anton Mitterer 2010-11-07 22:44 ` Arno Wagner 2010-11-04 8:45 ` Milan Broz 2010-11-04 12:16 ` Heinz Diehl 2 siblings, 2 replies; 16+ messages in thread From: Jean-Michel Pouré - GOOZE @ 2010-11-04 5:31 UTC (permalink / raw) To: dm-crypt Le mercredi 03 novembre 2010 à 23:34 +0100, Arno Wagner a écrit : > The main dm-crypt/LUKS focus is encrypted partitions in > an otherwise not encrypted system. Thank you for answers. Reading them, I understand I did not explain correctly. I would like to encrypt a whole system using dm-crypt. The problem is that I have to run pcsc prior to mounting partitions. But then pcsc will need access to libraries, which need to be on a mounted partition. Is there a way around? Kind regards, -- Jean-Michel Pouré - Gooze - http://www.gooze.eu ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE @ 2010-11-05 13:48 ` Christoph Anton Mitterer 2010-11-05 14:21 ` Arno Wagner 2010-11-05 16:29 ` Ma Begaj 2010-11-07 22:44 ` Arno Wagner 1 sibling, 2 replies; 16+ messages in thread From: Christoph Anton Mitterer @ 2010-11-05 13:48 UTC (permalink / raw) To: jmpoure; +Cc: dm-crypt [-- Attachment #1: Type: text/plain, Size: 634 bytes --] On Thu, 2010-11-04 at 06:31 +0100, Jean-Michel Pouré - GOOZE wrote: > I would like to encrypt a whole system using dm-crypt. The problem is > that I have to run pcsc prior to mounting partitions. But then pcsc will > need access to libraries, which need to be on a mounted partition. > > Is there a way around? Simply include all required stuff (binaries libraries, etc) in the initramfs image. The (actually booting) kernel and initramfs image need to be unencrypted anyways. E.g. Debian brings you nice tools to include something in initramfs images + its (library)dependencies (copy_exec). Cheers, Chris. [-- Attachment #2: smime.p7s --] [-- Type: application/x-pkcs7-signature, Size: 3387 bytes --] ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-05 13:48 ` Christoph Anton Mitterer @ 2010-11-05 14:21 ` Arno Wagner 2010-11-05 15:14 ` Viorel Tabara 2010-11-05 16:29 ` Ma Begaj 1 sibling, 1 reply; 16+ messages in thread From: Arno Wagner @ 2010-11-05 14:21 UTC (permalink / raw) To: dm-crypt On Fri, Nov 05, 2010 at 02:48:52PM +0100, Christoph Anton Mitterer wrote: > On Thu, 2010-11-04 at 06:31 +0100, Jean-Michel Pour?? - GOOZE wrote: > > I would like to encrypt a whole system using dm-crypt. The problem is > > that I have to run pcsc prior to mounting partitions. But then pcsc will > > need access to libraries, which need to be on a mounted partition. > > > > Is there a way around? > > Simply include all required stuff (binaries libraries, etc) in the > initramfs image. > > The (actually booting) kernel and initramfs image need to be unencrypted > anyways. > > E.g. Debian brings you nice tools to include something in initramfs > images + its (library)dependencies (copy_exec). An alternative would also be a static compile with the library functions in the executable. That can be a bit painful to do at thimes though and the executable will be pretty large. You will also need to the the static libraries for that, AFAIK. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-05 14:21 ` Arno Wagner @ 2010-11-05 15:14 ` Viorel Tabara 0 siblings, 0 replies; 16+ messages in thread From: Viorel Tabara @ 2010-11-05 15:14 UTC (permalink / raw) To: dm-crypt On Fri, 5 Nov 2010 15:21:34 +0100, Arno Wagner <arno@wagner.name> wrote to dm-crypt@saout.de and CC-ed to : > On Fri, Nov 05, 2010 at 02:48:52PM +0100, Christoph Anton Mitterer wrote: > > On Thu, 2010-11-04 at 06:31 +0100, Jean-Michel Pour?? - GOOZE wrote: > > > I would like to encrypt a whole system using dm-crypt. The problem is > > > that I have to run pcsc prior to mounting partitions. But then pcsc will > > > need access to libraries, which need to be on a mounted partition. > > > > > > Is there a way around? > > > > Simply include all required stuff (binaries libraries, etc) in the > > initramfs image. > > > > The (actually booting) kernel and initramfs image need to be unencrypted > > anyways. > > > > E.g. Debian brings you nice tools to include something in initramfs > > images + its (library)dependencies (copy_exec). > > An alternative would also be a static compile with the library > functions in the executable. That can be a bit painful to do > at thimes though and the executable will be pretty large. You > will also need to the the static libraries for that, AFAIK. > Sources of inspiration I used: http://en.gentoo-wiki.com/wiki/Booting_encrypted_system_from_USB_stick#Preparing_the_USB_stick http://en.gentoo-wiki.com/wiki/DM-Crypt_with_LUKS http://en.gentoo-wiki.com/wiki/DM-Crypt HTH, Viorel ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-05 13:48 ` Christoph Anton Mitterer 2010-11-05 14:21 ` Arno Wagner @ 2010-11-05 16:29 ` Ma Begaj 2010-11-06 18:16 ` Jean-Michel Pouré - GOOZE 1 sibling, 1 reply; 16+ messages in thread From: Ma Begaj @ 2010-11-05 16:29 UTC (permalink / raw) To: dm-crypt Am 5. November 2010 14:48 schrieb Christoph Anton Mitterer <christoph.anton.mitterer@physik.uni-muenchen.de>: > On Thu, 2010-11-04 at 06:31 +0100, Jean-Michel Pouré - GOOZE wrote: >> I would like to encrypt a whole system using dm-crypt. The problem is >> that I have to run pcsc prior to mounting partitions. But then pcsc will >> need access to libraries, which need to be on a mounted partition. >> >> Is there a way around? > > Simply include all required stuff (binaries libraries, etc) in the > initramfs image. > > The (actually booting) kernel and initramfs image need to be unencrypted > anyways. > two additional ideas to make it more secure: 1. You can put your initramfs image ona usb stick to have it even more secure. 2. A script on a encrypted root partition could compare (upon decryption) md5 checksum of initramfs with the saved md5 checksum (with md5sum) and show alert message if sums do not match. ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-05 16:29 ` Ma Begaj @ 2010-11-06 18:16 ` Jean-Michel Pouré - GOOZE 2010-11-08 21:58 ` Mario 'BitKoenig' Holbe 0 siblings, 1 reply; 16+ messages in thread From: Jean-Michel Pouré - GOOZE @ 2010-11-06 18:16 UTC (permalink / raw) To: dm-crypt Le vendredi 05 novembre 2010 à 17:29 +0100, Ma Begaj a écrit : > A script on a encrypted root partition could compare (upon decryption) > md5 > checksum of initramfs with the saved md5 checksum (with md5sum) and > show > alert message if sums do not match. When using smartcards, secrets are not displayed. So why should we need to crypt the initramfs at first stage? We only need to boot in first stage, non-encrypted, and then request secrets from PKCS#11 and uncrypt the complete system. What do you think? -- Jean-Michel Pouré - Gooze - http://www.gooze.eu ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-06 18:16 ` Jean-Michel Pouré - GOOZE @ 2010-11-08 21:58 ` Mario 'BitKoenig' Holbe 0 siblings, 0 replies; 16+ messages in thread From: Mario 'BitKoenig' Holbe @ 2010-11-08 21:58 UTC (permalink / raw) To: dm-crypt Jean-Michel Pouré - GOOZE <jmpoure@gooze.eu> wrote: > When using smartcards, secrets are not displayed. So why should we need > to crypt the initramfs at first stage? We only need to boot in first > stage, non-encrypted, and then request secrets from PKCS#11 and uncrypt > the complete system. Well, what you should need does primarily depend on what you want to have, i.e. on your security goals. If your only security goal is the typical "stolen notebook" scenario, i.e. prevent off-line access to your data, you don't need to care about crypted initramfs or whatever. If your security goals go further and you want to prevent secrets (keys, passphrases) from being stolen you have to care about things like root-access, backdoors, loggers, etc. An untrusted initramfs is able to install such backdoors or loggers - so are untrusted boot-loaders, BIOSes and hardwares. If your security goal is to establish a full trust-chain, you have to care about lot more things. regards Mario -- As a rule, the more bizarre a thing is, the less mysterious it proves to be. -- Sherlock Holmes by Arthur Conan Doyle ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE 2010-11-05 13:48 ` Christoph Anton Mitterer @ 2010-11-07 22:44 ` Arno Wagner 1 sibling, 0 replies; 16+ messages in thread From: Arno Wagner @ 2010-11-07 22:44 UTC (permalink / raw) To: dm-crypt On Thu, Nov 04, 2010 at 06:31:53AM +0100, Jean-Michel Pour? - GOOZE wrote: > Le mercredi 03 novembre 2010 ?? 23:34 +0100, Arno Wagner a ??crit : > > The main dm-crypt/LUKS focus is encrypted partitions in > > an otherwise not encrypted system. > > Thank you for answers. Reading them, I understand I did not explain > correctly. > > I would like to encrypt a whole system using dm-crypt. The problem is > that I have to run pcsc prior to mounting partitions. But then pcsc will > need access to libraries, which need to be on a mounted partition. > > Is there a way around? No. You have to read something from disk in order to boot and that something needs to be unencrypted. You can do an initrd that is unencrypted or a boot-sector like TrueCrypt (and grub 2?), but neither quelifies as full system encryption. For dm-crypt, the initrd is the means of coice. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 22:34 ` Arno Wagner 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE @ 2010-11-04 8:45 ` Milan Broz 2010-11-04 12:16 ` Heinz Diehl 2 siblings, 0 replies; 16+ messages in thread From: Milan Broz @ 2010-11-04 8:45 UTC (permalink / raw) To: dm-crypt On 11/03/2010 11:34 PM, Arno Wagner wrote: > The only interface for integrating external keys is by > reading them from file or stdin and that is by desing > to keep things simple. I am maintaining it with the basic idea that libcrypsetup/cryptsetup is simple tool to configure encrypted partitions using kernel crypto. Nothing more, nothing less. New api in libcrypsetup provides two trivial interfaces to get passphrase or key - directly provided buffer (owned by application) or keyfile. For the compatibility reasons it fallbacks to read from terminal/stdin but the focus is to move passphrase reading into application responsibility. IOW if anyone want to handle LUKS mapping in program (imagine e.g. systemd - issue of these days) it can use libcryptsetup and handle safe password reading dialog in application. (Using stdin in cryptsetup in scripts is problematic - you cannot control and wipe all buffers. But this option will be always there. I mean constructions like echo "password" | cryptsetup luksOpen ...) Handling of various tokens and cards is always wrapper around cryptsetup - (either scripts or binaries linked to libcryptsetup). Maybe one day these scripts will be part of upstream tarball, currently it is up to the distribution to add them. Milan ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 22:34 ` Arno Wagner 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE 2010-11-04 8:45 ` Milan Broz @ 2010-11-04 12:16 ` Heinz Diehl 2010-11-04 12:57 ` Mario 'BitKoenig' Holbe 2 siblings, 1 reply; 16+ messages in thread From: Heinz Diehl @ 2010-11-04 12:16 UTC (permalink / raw) To: dm-crypt On 04.11.2010, Arno Wagner wrote: > Having a not completely encrypted initrd and kernel does > not qualify as "completely encrypted system on boot". How would you boot such a system when initramfs / initrd is encrypted? I'm just curious. ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-04 12:16 ` Heinz Diehl @ 2010-11-04 12:57 ` Mario 'BitKoenig' Holbe 2010-11-04 16:40 ` Arno Wagner 0 siblings, 1 reply; 16+ messages in thread From: Mario 'BitKoenig' Holbe @ 2010-11-04 12:57 UTC (permalink / raw) To: dm-crypt Heinz Diehl <htd@fancy-poultry.org> wrote: > On 04.11.2010, Arno Wagner wrote: >> Having a not completely encrypted initrd and kernel does > How would you boot such a system when initramfs / initrd is encrypted? Enable your boot-loader to decrypt it. Meanwhile, grub can do this. This somewhat reduces but, of course, not eliminates the trust-problem: instead of having to trust your hardware, BIOS, boot-loader, kernel, and initramfs, you now have to trust your hardware, BIOS, and boot-loader only. regards Mario -- Wine is fine, but wiskey is quicker. Suicide is slow with liquor. -- Ozzy Osbourne ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-04 12:57 ` Mario 'BitKoenig' Holbe @ 2010-11-04 16:40 ` Arno Wagner 0 siblings, 0 replies; 16+ messages in thread From: Arno Wagner @ 2010-11-04 16:40 UTC (permalink / raw) To: dm-crypt On Thu, Nov 04, 2010 at 01:57:23PM +0100, Mario 'BitKoenig' Holbe wrote: > Heinz Diehl <htd@fancy-poultry.org> wrote: > > On 04.11.2010, Arno Wagner wrote: > >> Having a not completely encrypted initrd and kernel does > > How would you boot such a system when initramfs / initrd is encrypted? > > Enable your boot-loader to decrypt it. Meanwhile, grub can do this. One other option is trusted hardware, that can do the initial decryption. > This somewhat reduces but, of course, not eliminates the trust-problem: > instead of having to trust your hardware, BIOS, boot-loader, kernel, and > initramfs, you now have to trust your hardware, BIOS, and boot-loader > only. I completely agree. And with trusted hardware, you still have to trust the hardware. However, there is some (limited) benefit, namely the earlier in the boot process, the harder it gets for an attacker, i.e. the more expensive. Also, with good trusted hardware, remote attacks become infeasible and you have to physically access the hardware. The same could be done with booting from a write-protected memory stick or CD/DVD. In all cases a class vulnerability remains, namely that everything is open once the system runs. This is one reason, why encrypted root is basically only worthwhile if the attacker _has_ physical access. But in that case a whole set of new attacks become possible, that encryption does not help against, such as hardware-keyloggers, patched BIOSes, changes to your read-only boot-medium, etc.. I doubt that system encryption does help a lot in cases other than when the complete system gets stolen (laptop). But then normal system encryption for Windoes (e.g. TrueCrytp), and data+tmp+var+swap encryption for Linux is quite enough. Side note: Benefit of a chipcard in the scope of disk encryption is that people that have trouble with passwords do not need to remember them. I really don't see any other. This can be a valid application, though. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [dm-crypt] Feitian PKI donation to dm-crypt projetc 2010-11-03 18:26 [dm-crypt] Feitian PKI donation to dm-crypt projetc Jean-Michel Pouré - GOOZE 2010-11-03 20:29 ` Christoph Anton Mitterer 2010-11-03 22:34 ` Arno Wagner @ 2010-11-04 8:52 ` Milan Broz 2 siblings, 0 replies; 16+ messages in thread From: Milan Broz @ 2010-11-04 8:52 UTC (permalink / raw) To: jmpoure; +Cc: dm-crypt On 11/03/2010 07:26 PM, Jean-Michel Pouré - GOOZE wrote: > We would be happy to offer three Feitian PKI smartcards to the dm-crypt > project. Free Software developer can register here: > http://gooze.eu/feitian-pki-free-software-developer-card > > Also, we are currently writing a HOWTO to publish on GOOZE. > > Is there a way to enable dm-crypt using opensc-pkcs11.so on startup? > The idea is to have a complete encrypted system on boot. Hi, see my response later in this thread - it is not directly cryptsetup/dm-crypt job but it is closely related. > This probably involves creating an initrd with OpenSSL and OpenSC > included. Did anyone succeed in this? I can probably send this to people who maintain such things in Fedora distro, but maybe you already did that. Milan ^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2010-11-08 21:59 UTC | newest] Thread overview: 16+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2010-11-03 18:26 [dm-crypt] Feitian PKI donation to dm-crypt projetc Jean-Michel Pouré - GOOZE 2010-11-03 20:29 ` Christoph Anton Mitterer 2010-11-03 22:34 ` Arno Wagner 2010-11-04 5:31 ` Jean-Michel Pouré - GOOZE 2010-11-05 13:48 ` Christoph Anton Mitterer 2010-11-05 14:21 ` Arno Wagner 2010-11-05 15:14 ` Viorel Tabara 2010-11-05 16:29 ` Ma Begaj 2010-11-06 18:16 ` Jean-Michel Pouré - GOOZE 2010-11-08 21:58 ` Mario 'BitKoenig' Holbe 2010-11-07 22:44 ` Arno Wagner 2010-11-04 8:45 ` Milan Broz 2010-11-04 12:16 ` Heinz Diehl 2010-11-04 12:57 ` Mario 'BitKoenig' Holbe 2010-11-04 16:40 ` Arno Wagner 2010-11-04 8:52 ` Milan Broz
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