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PAPERKEY(1)		    General Commands Manual		   PAPERKEY(1)

NAME
       paperkey	- extract secret information out of OpenPGP secret keys

SYNOPSIS
       paperkey	[--secret-key=FILE] [--output=FILE] [--output-type=base16|raw]
       [--output-width=WIDTH]

       paperkey	--pubring=FILE [--secrets=FILE]	[--input-type=auto|base16|raw]
       [--output=FILE] [--ignore-crc-error] [--comment=STRING] [--file-format]

       paperkey	--version

MOTIVATION
       As  with	 all  data,  secret keys should	be backed up.  In fact,	secret
       keys should be backed up	even better than other data, because they  are
       impossible  to  recreate	should they ever be lost.  All files encrypted
       to lost keys are	forever	(or at least for a long	time)  undecipherable.
       In addition to keeping backups of secret	key information	on digital me-
       dia  such as USB-sticks or CDs it is reasonable to keep an if-all-else-
       fails copy on plain old paper, for use should your digital  media  ever
       become  unreadable for whatever reason.	Stored properly, paper is able
       to keep information for several decades or longer.

       With GnuPG, PGP,	or other OpenPGP implementations the secret  key  usu-
       ally  contains  a lot more than just the	secret numbers that are	impor-
       tant.  They also	hold all the public values of key pairs, user ids, ex-
       piration	times and more.	 In order to minimize the information that has
       to be entered manually or with the help of  OCR,	 QR  code  or  similar
       software,  paperkey extracts just the secret information	out of OpenPGP
       secret keys.  For recovering a secret key it is assumed that the	public
       key is still available, for instance from public	Internet keyservers.

DESCRIPTION
       paperkey	has two	modes of operation:

       The first mode creates "paperkeys" by extracting	just the secret	infor-
       mation from a secret key, formatting the	data in	 a  way	 suitable  for
       printing	or in a	raw mode for further processing.

       The  other mode rebuilds	secret keys from such a	paperkey and a copy of
       the public key, also verifying the checksums embedded in	the  paperkey.
       This  mode  is selected when the	--pubring option is used, which	is re-
       quired in that case.  If	a passphrase was set on	 the  original	secret
       key, the	same passphrase	is set on the rebuilt key.

       Input  is  read	from standard-in except	when the --secret-key or --se-
       crets option is used; output is printed to standard-out,	unless changed
       with the	--output option.

SECURITY CONSIDERATIONS
       Please note that	paperkey does not change the protection	and encryption
       status of and security requirements for storing your secret key.	If the
       secret key was protected	by a passphrase	so is the  paperkey.   If  the
       secret key was unprotected the paperkey will not	be protected either.

OPTIONS
       --help, -h Display a short help message and exit	successfully.

       --version, -V
	      Print  version  information  and	copyright information and exit
	      successfully.

       --verbose, -v
	      Print status and progress	information  to	 standard-error	 while
	      processing the input.  Repeat for	even more output.

       --output=FILE, -o
	      Redirect	output	to the file given instead of printing to stan-
	      dard-output.

       --comment=STRING
	      Include the specified comment in the base16 output.

       --file-format
	      Paperkey automatically includes the file format it uses as  com-
	      ments  at	 the  top  of  the base16 output.  This	command	simply
	      prints out the file format and exits successfully.

OPTIONS	FOR EXTRACTING SECRET INFORMATION
       --output-type=base16, --output-type=raw
	      Select the output	type.  The base16 style	encodes	 the  informa-
	      tion  in the style of a classic hex-dump,	including line numbers
	      and per-line CRC checksums to facilitate	localizing  errors  in
	      the  input  file during the recovery phase.  The raw, or binary,
	      mode is just a raw dump of the secret information, intended  for
	      feeding to barcode generators or the like.

       --output-width=WIDTH
	      Choose  line width in the	base16 output mode.  The default is 78
	      characters.

       --secret-key=FILE
	      File to read the secret key from.	 If this option	is  not	 given
	      paperkey reads from standard-input.

OPTIONS	FOR RE-CREATING	PRIVATE	KEYS
       --input-type=auto, --input-type=base16, --input-type=raw
	      Specify that the given input is either in	base16 format, as pro-
	      duced  by	 paperkey, or in raw format.  The default, auto, tries
	      to automatically detect the format in use.

       --pubring=FILE
	      File to read public key information from.	 It  is	 assumed  that
	      the  user	can get	the public key from sources like public	Inter-
	      net keyservers.

       --secrets=FILE
	      File to read the extracted secrets, the paperkey,	from.  If this
	      is not given then	the information	is read	from standard-input.

       --ignore-crc-error
	      Do not reject corrupt input and continue despite any CRC errors.

EXAMPLES
       Take  the  secret  key  in   key.gpg   and   generate   a   text	  file
       to-be-printed.txt that contains the secret data:

       $ paperkey --secret-key my-secret-key.gpg --output to-be-printed.txt

       Take  the  secret  key data in my-key-text-file.txt and combine it with
       my-public-key.gpg to reconstruct	my-secret-key.gpg:

       $ paperkey --pubring my-public-key.gpg  --secrets  my-key-text-file.txt
       --output	my-secret-key.gpg

       If  --output  is	 not  specified,  the output goes to stdout.  If --se-
       cret-key	is not specified, the data is read from	stdin so  you  can  do
       things like:

       $ gpg --export-secret-key my-key	| paperkey | lpr

SEE ALSO
       gpg(1), http://www.jabberwocky.com/software/paperkey/

AUTHORS
       paperkey	is written by David Shaw <dshaw@jabberwocky.com>.

PAPERKEY			   June	2012			   PAPERKEY(1)

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