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tpm2_nvdefine(1)	    General Commands Manual	      tpm2_nvdefine(1)

       tpm2_nvdefine(1)	- Define a TPM Non-Volatile (NV) index.

       tpm2_nvdefine [OPTIONS] [ARGUMENT]

       tpm2_nvdefine(1)	- Define an NV index with given	auth value.  The index
       is specified as an argument.  It	can be specified as raw	handle	or  an
       offset  value  to  the nv handle	range "TPM2_HR_NV_INDEX".  If an index
       isn't specified,	the tool uses the first	free index.  The tool  outputs
       the nv index defined on success.

       o -C, --hierarchy=OBJECT:
	 Specifies the handle used to authorize.  Defaults to o, TPM_RH_OWNER,
	 when no value has been	specified.  Supported options are:

	 o o for TPM_RH_OWNER


	 o <num> where a hierarchy handle or nv-index may be used.

       +o -s, --size=NATURAL_NUMBER:

	 Specifies the size of data area in  bytes.   Defaults	to  MAX_NV_IN-
	 DEX_SIZE which	is typically 2048.

       o -a, --attributes=ATTRIBUTES

	 Specifies  the	 attribute values for the nv region used when creating
	 the entity.  Either the raw bitfield  mask  or	 "nice-names"  may  be
	 used.	 See  section "NV Attributes" for more details.	 If not	speci-
	 fied, the attributes default to various selections based on the hier-
	 archy	the  index is defined in.  For the owner hiearchy the defaults


	 o TPMA_NV_OWNERREAD For the platform hiearchy,	the defaults are:


	 o TPMA_NV_PPREAD If a policy file is specified, the  hiearchy	chosen
	   default attributes are bitwise or'd with:


	 o TPMA_NV_POLICYREAD  If a policy file	is NOT specified, the hiearchy
	   chosen default attributes are bitwise or'd with:



       o -P, --hierarchy-auth=AUTH:

	 Specifies the authorization value for the  hierarchy.	 Authorization
	 values	 should	 follow	 the "authorization formatting standards", see
	 section "Authorization	Formatting".

       o -p, --index-auth=AUTH:

	 Specifies the password	of NV Index when created.  HMAC	 and  Password
	 authorization	values	should	follow	the  "authorization formatting
	 standards", see section "Authorization	Formatting".

       o -L, --policy=FILE:

	 Specifies the policy digest file for policy based authorizations.

       o --cphash=FILE

	 File path to record the hash of the command parameters.  This is com-
	 monly termed as cpHash.  NOTE:	When this option is selected, The tool
	 will not actually execute the command,	it simply returns a cpHash.

       o ARGUMENT the command line argument specifies the NV index  or	offset

Context	Object Format
       The  type  of a context object, whether it is a handle or file name, is
       determined according to the following logic in-order:

       o If the	argument is a file path, then the file is loaded as a restored
	 TPM transient object.

       o If the	argument is a prefix match on one of:

	 o owner: the owner hierarchy

	 o platform: the platform hierarchy

	 o endorsement:	the endorsement	hierarchy

	 o lockout: the	lockout	control	persistent object

       o If  the  argument argument can	be loaded as a number it will be treat
	 as a handle, e.g.  0x81010013 and used	directly.OBJECT.

Authorization Formatting
       Authorization for use of	an object in TPM2.0 can	come  in  3  different
       forms: 1.  Password 2.  HMAC 3.	Sessions

       NOTE:  "Authorizations  default	to  the	EMPTY PASSWORD when not	speci-

       Passwords are interpreted in the	following  forms  below	 using	prefix

       Note:  By  default  passwords are assumed to be in the string form when
       they do not have	a prefix.

       A string	password, specified by prefix  "str:"  or  it's	 absence  (raw
       string without prefix) is not interpreted, and is directly used for au-


       A hex-string password, specified	by prefix "hex:" is converted  from  a
       hexidecimal  form  into a byte array form, thus allowing	passwords with
       non-printable and/or terminal un-friendly characters.


       A file based password, specified	be prefix "file:" should be  the  path
       of  a  file  containing the password to be read by the tool or a	"-" to
       use stdin.  Storing passwords in	files  prevents	 information  leakage,
       passwords passed	as options can be read from the	process	list or	common
       shell history features.

	      #	to use stdin and be prompted

	      #	to use a file from a path

	      #	to echo	a password via stdin:
	      echo foobar | tpm2_tool -p file:-

	      #	to use a bash here-string via stdin:

	      tpm2_tool	-p file:- <<< foobar

       When using a policy session to authorize	the use	of an  object,	prefix
       the  option argument with the session keyword.  Then indicate a path to
       a session file that was created with tpm2_startauthsession(1).  Option-
       ally, if	the session requires an	auth value to be sent with the session
       handle (eg policy password), then append	a + and	a string as  described
       in the Passwords	section.

       To use a	session	context	file called session.ctx.


       To use a	session	context	file called session.ctx	AND send the authvalue


       To use a	session	context	file called session.ctx	AND send the HEX auth-
       value 0x11223344.


   PCR Authorizations
       You  can	satisfy	a PCR policy using the "pcr:" prefix and the PCR mini-
       language.      The     PCR     minilanguage     is     as      follows:

       The PCR spec is documented in in	the section "PCR bank specifiers".

       The  raw-pcr-file  is an	optional the output of the raw PCR contents as
       returned	by tpm2_pcrread(1).

       PCR bank	specifiers (common/

       To satisfy a PCR	policy of sha256 on banks 0, 1,	2 and 3	use a specifi-
       er of:


       specifying AUTH.

Object Attributes
       Object Attributes are used to control various properties	of created ob-
       jects.  When specified as an option, either the raw  bitfield  mask  or
       "nice-names"  may  be used.  The	values can be found in Table 31	Part 2
       of the TPM2.0 specification, which can be found here:


       Nice  names are calculated by taking the	name field of table 31 and re-
       moving the prefix TPMA_OBJECT_ and lowercasing the result.   Thus,  TP-
       MA_OBJECT_FIXEDTPM  becomes  fixedtpm.	Nice names can be joined using
       the bitwise or "|" symbol.

       For instance, to	set The	fields TPMA_OBJECT_FIXEDTPM, TPMA_OBJECT_NODA,
       and TPMA_OBJECT_SIGN_ENCRYPT, the argument would	be:

       fixedtpm|noda|sign specifying the nv attributes ATTRIBUTES.

       This  collection	of options are common to many programs and provide in-
       formation that many users may expect.

       o -h, --help=[man|no-man]: Display the tools manpage.  By  default,  it
	 attempts  to  invoke  the  manpager for the tool, however, on failure
	 will output a short tool summary.  This is the	same behavior  if  the
	 "man"	option argument	is specified, however if explicit "man"	is re-
	 quested, the tool will	provide	errors from man	 on  stderr.   If  the
	 "no-man"  option  if  specified, or the manpager fails, the short op-
	 tions will be output to stdout.

	 To successfully use the manpages feature requires the manpages	to  be
	 installed or on MANPATH, See man(1) for more details.

       o -v,  --version:  Display version information for this tool, supported
	 tctis and exit.

       o -V, --verbose:	Increase the information that the tool prints  to  the
	 console  during  its  execution.  When	using this option the file and
	 line number are printed.

       o -Q, --quiet: Silence normal tool output to stdout.

       o -Z, --enable-errata: Enable the application of	errata fixups.	Useful
	 if  an	 errata	fixup needs to be applied to commands sent to the TPM.
	 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent.   in-
	 formation many	users may expect.

TCTI Configuration
       The  TCTI  or  "Transmission  Interface"	is the communication mechanism
       with the	TPM.  TCTIs can	be changed for communication with TPMs	across
       different mediums.

       To control the TCTI, the	tools respect:

       1. The command line option -T or	--tcti

       2. The environment variable: TPM2TOOLS_TCTI.

       Note:  The  command  line option	always overrides the environment vari-

       The current known TCTIs are:

       o tabrmd	    -	  The	  resource     manager,	    called	tabrmd
	 (	  Note that tabrmd and
	 abrmd as a tcti name are synonymous.

       o mssim - Typically used	for communicating to the TPM software  simula-

       o device	- Used when talking directly to	a TPM device file.

       o none  - Do not	initalize a connection with the	TPM.  Some tools allow
	 for off-tpm options and thus support not using	a TCTI.	 Tools that do
	 not  support  it  will	error when attempted to	be used	without	a TCTI
	 connection.  Does not support ANY options and MUST  BE	 presented  as
	 the exact text	of "none".

       The  arguments  to  either  the	command	line option or the environment
       variable	are in the form:


       Specifying an empty string for  either  the  <tcti-name>	 or  <tcti-op-
       tion-config> results in the default being used for that portion respec-

   TCTI	Defaults
       When a TCTI is not specified, the default TCTI is  searched  for	 using
       dlopen(3)  semantics.   The  tools  will	 search	for tabrmd, device and
       mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND.  You  can	 query
       what TCTI will be chosen	as the default by using	the -v option to print
       the version information.	 The "default-tcti" key-value pair will	 indi-
       cate which of the aforementioned	TCTIs is the default.

   Custom TCTIs
       Any TCTI	that implements	the dynamic TCTI interface can be loaded.  The
       tools internally	use dlopen(3), and the raw tcti-name value is used for
       the lookup.  Thus, this could be	a path to the shared library, or a li-
       brary name as understood	by dlopen(3) semantics.

       This collection of options are used to configure	the various known TCTI
       modules available:

       o device: For the device	TCTI, the TPM character	device file for	use by
	 the device TCTI can be	specified.  The	default	is /dev/tpm0.

	 Example:   -T	 device:/dev/tpm0   or	 export	   TPM2TOOLS_TCTI="de-

       _o mssim:	 For  the  mssim  TCTI,	the domain name	or IP address and port
	 number	used by	the simulator  can  be	specified.   The  default  are and 2321.

	 Example:  -T  mssim:host=localhost,port=2321  or export TPM2TOOLS_TC-

       _o abrmd:	For the	abrmd TCTI, the	configuration string format is	a  se-
	 ries  of  simple  key value pairs separated by	a ',' character.  Each
	 key and value string are separated by a '=' character.

	 o TCTI	abrmd supports two keys:

	   1. 'bus_name' : The name of	the  tabrmd  service  on  the  bus  (a

	   2. 'bus_type' : The type of the dbus	instance (a string) limited to
	      'session'	and 'system'.

	 Specify the tabrmd tcti name and a config string of  bus_name=com.ex-


	 Specify the default (abrmd) tcti and a	config string of bus_type=ses-


	 NOTE: abrmd and tabrmd	are synonymous.	 the various known  TCTI  mod-

	      tpm2_nvdefine   0x1500016	-C 0x40000001 -s 32 -a 0x2000A

	      tpm2_nvdefine   0x1500016	-C 0x40000001 -s 32 \
	      -a ownerread|ownerwrite|policywrite -p 1a1b1c

       Tools can return	any of the following codes:

       o 0 - Success.

       o 1 - General non-specific error.

       o 2 - Options handling error.

       o 3 - Authentication error.

       o 4 - TCTI related error.

       o 5 - Non supported scheme.  Applicable to tpm2_testparams.

       Github Issues (

       See the Mailing List (

tpm2-tools						      tpm2_nvdefine(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | Context Object Format | Authorization Formatting | Object Attributes | COMMON OPTIONS | TCTI Configuration | TCTI OPTIONS | EXAMPLES | Returns | BUGS | HELP

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