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tpm2_encryptdecrypt(1)	    General Commands Manual	tpm2_encryptdecrypt(1)

       tpm2_encryptdecrypt(1) -	Performs symmetric encryption or decryption.

       tpm2_encryptdecrypt [OPTIONS] [ARGUMENT]

       tpm2_encryptdecrypt(1)  -  Performs  symmetric encryption or decryption
       with a specified	symmetric key on the contents of FILE.	If FILE	is not
       specified, defaults to stdin.

       o -c, --key-context=OBJECT:

	 The encryption	key object.

       o -p, --auth=AUTH:

	 The authorization value for the encryption key	object.

       o -d, --decrypt:

	 Perform a decrypt operation.  Defaults	to encryption when this	option
	 is not	specified.

       o -e, --pad:

	 Enable	pkcs7 padding for applicable AES encryption modes cfb/cbc/ecb.
	 Applicable  only  to  encryption  and	for input data with last block
	 shorter than encryption block length.

       o -o, --output=FILE or STDOUT:

	 The output file path for either the encrypted or decrypted data.   If
	 not specified,	defaults to stdout.

       o -G, --mode=ALGORITHM:

	 The  key  algorithm  associated with this object.  Defaults to	object
	 properties or CFB if not defined.

       o -t, --iv=FILE:

	 Optional initialization vector	to use.	 Defaults to 0's.  Syntax  al-
	 lows  for  an input file and output file source to be specified.  The
	 input file path is first, optionally followed by a colon ":" and  the
	 output	 iv  path.   This  output iv can be saved for subsequent calls
	 when chaining.

       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 input	file path FILE
	 of the	data to	encrypt	or decrypt.

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.

Algorithm Specifiers
       Options that take algorithms support "nice-names".

       There  are two major algorithm specification string classes, simple and
       complex.	 Only certain algorithms will be accepted by the TPM, based on
       usage and conditions.

   Simple specifiers
       These are strings with no additional specification data.	 When creating
       objects,	non-specified portions of an object are	assumed	 to  defaults.
       You can find the	list of	known "Simple Specifiers Below".

       o rsa

       o ecc

       o aes

       o camellia

   Hashing Algorithms
       o sha1

       o sha256

       o sha384

       o sha512

       o sm3_256

       o sha3_256

       o sha3_384

       o sha3_512

   Keyed Hash
       o hmac

       o xor

   Signing Schemes
       o rsassa

       o rsapss

       o ecdsa

       o ecdaa

       o ecschnorr

   Asymmetric Encryption Schemes
       o oaep

       o rsaes

       o ecdh

       o ctr

       o ofb

       o cbc

       o cfb

       o ecb

       o null

   Complex Specifiers
       Objects,	 when  specified  for creation by the TPM, have	numerous algo-
       rithms to populate in the public	data.  Things like  type,  scheme  and
       asymmetric  details,  key  size,	 etc.  Below is	the general format for
       specifying this data: <type>:<scheme>:<symmetric-details>

   Type	Specifiers
       This portion of the complex algorithm specifier is required.   The  re-
       maining	scheme	and  symmetric	details	will default based on the type
       specified and the type of the object being created.

       o aes - Default AES: aes128

       o aes128<mode> -	128 bit	AES with optional mode	(ctr|ofb|cbc|cfb|ecb).
	 If mode is not	specified, defaults to null.

       o aes192<mode> -	Same as	aes128<mode>, except for a 192 bit key size.

       o aes256<mode> -	Same as	aes128<mode>, except for a 256 bit key size.

       o ecc - Elliptical Curve, defaults to ecc256.

       o ecc192	- 192 bit ECC

       o ecc224	- 224 bit ECC

       o ecc256	- 256 bit ECC

       o ecc384	- 384 bit ECC

       o ecc521	- 521 bit ECC

       o rsa - Default RSA: rsa2048

       o rsa1024 - RSA with 1024 bit keysize.

       o rsa2048 - RSA with 2048 bit keysize.

       o rsa4096 - RSA with 4096 bit keysize.

   Scheme Specifiers
       Next, is	an optional field, it can be skipped.

       Schemes	are  usually Signing Schemes or	Asymmetric Encryption Schemes.
       Most signing schemes take a hash	algorithm directly following the sign-
       ing  scheme.   If the hash algorithm is missing,	it defaults to sha256.
       Some take no arguments, and some	take multiple arguments.

   Hash	Optional Scheme	Specifiers
       These scheme specifiers are followed by a dash and a valid  hash	 algo-
       rithm, For example: oaep-sha256.

       o oaep

       o ecdh

       o rsassa

       o rsapss

       o ecdsa

       o ecschnorr

   Multiple Option Scheme Specifiers
       This  scheme  specifier	is  followed by	a count	(max size UINT16) then
       folloed by a dash(-) and	a valid	hash algorithm.	 * ecdaa For  example,
       ecdaa4-sha256.  If no count is specified, it defaults to	4.

   No Option Scheme Specifiers
       This scheme specifier takes NO arguments.  * rsaes

   Symmetric Details Specifiers
       This  field is optional,	and defaults based on the type of object being
       created and it's	attributes.  Generally,	any valid Symmetric  specifier
       from  the Type Specifiers list should work.  If not specified, an asym-
       metric objects symmetric	details	defaults to aes128cfb.

   Create an rsa2048 key with an rsaes asymmetric encryption scheme
       tpm2_create -C parent.ctx -G rsa2048:rsaes -u -r	key.priv

   Create an ecc256 key	with an	ecdaa signing scheme with a count of 4
       and sha384 hash

       /tpm2_create -C parent.ctx -G ecc256:ec-
       daa4-sha384 -u -r key.priv cryptographic	algorithms ALGORITHM.

       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-

Create an AES key
	      tpm2_createprimary -c primary.ctx
	      tpm2_create -C primary.ctx -Gaes128 -u -r	key.priv
	      tpm2_load	-C primary.ctx -u -r key.priv -c key.ctx

Encrypt	and Decrypt some data
	      echo "my secret" > secret.dat
	      tpm2_encryptdecrypt -c key.ctx -o	secret.enc secret.dat
	      tpm2_encryptdecrypt -d -c	key.ctx	-o secret.dec secret.enc
	      cat secret.dec
	      my secret

       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_encryptdecrypt(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | Context Object Format | Authorization Formatting | Algorithm Specifiers | COMMON OPTIONS | TCTI Configuration | TCTI OPTIONS | EXAMPLES | Create an AES key | Encrypt and Decrypt some data | Returns | BUGS | HELP

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