1tpm2_createek(1) General Commands Manual tpm2_createek(1)
2
6 tpm2_createek(1) - Generate TCG profile compliant endorsement key.
7
9 tpm2_createek [OPTIONS]
10
12 tpm2_createek(1) - Generate TCG profile compliant endorsement key (EK),
13 which is the primary object of the endorsement hierarchy.
14 If a transient object is generated the tool outputs a context file
16 specified with -c.
17 Refer to: <http://www.trustedcomputinggroup.org/files/stat‐
19 ic_page_files/7CAA5687-1A4B-B294-D04080D058E86C5F>
20
22 • -P, --eh-auth=AUTH:
23 The authorization value for the endorsement hierarchy
25 • -w, --owner-auth=AUTH
27 The authorization value for the owner hierarchy.
29 • -c, --ek-context=OBJECT or FILE:
31 Either a file path or a persistent handle value to save the endorse‐
33 ment key.
34 If a value of - is passed the tool will find a vacant persistent han‐
36 dle to use and print out the automatically selected handle.
37 If one saves the context file via this option and the public key via
39 the -u option, the EK can be restored via a call to tpm2_loadexter‐
40 nal(1).
41 • -G, --key-algorithm=ALGORITHM:
43 The endorsement key algorithm. Supports:
44 • ecc - An P256 key.
46 • rsa - An RSA2048 key.
48 • keyedhash - hmac key.
50 • -u, --public=FILE:
52 The optional input for a file to save the public portion of endorse‐
54 ment key.
55 • -t, --template:
57 The optional manufacturer defined endorsement key template and nonce
59 from fixed NV Indices to populate the TPM2B_PUBLIC public area. See
60 the TCG EK Credential Profile specification for more information:
61 https://trustedcomputinggroup.org/wp-content/uploads/ TCG_IWG_Creden‐
62 tial_Profile_EK_V2.1_R13.pdf
63 • -f, --format:
65 Format selection for the public key output file. `tss' (the default)
67 will output a binary blob according to the TPM 2.0 Specification.
68 `pem' will output an OpenSSL compatible PEM encoded public key.
69 `der' will output an OpenSSL compatible DER encoded public key.
70 `tpmt' will output a binary blob of the TPMT_PUBLIC struct referenced
71 by TPM 2.0 specs.
72 Public key format.
74 References
77 The type of a context object, whether it is a handle or file name, is
78 determined according to the following logic in-order:
79 • If the argument is a file path, then the file is loaded as a restored
81 TPM transient object.
82 • If the argument is a prefix match on one of:
84 • owner: the owner hierarchy
86 • platform: the platform hierarchy
88 • endorsement: the endorsement hierarchy
90 • lockout: the lockout control persistent object
92 • If the argument argument can be loaded as a number it will be treat
94 as a handle, e.g. 0x81010013 and used directly._OBJECT_.
95
97 Authorization for use of an object in TPM2.0 can come in 3 different
98 forms: 1. Password 2. HMAC 3. Sessions
99 NOTE: “Authorizations default to the EMPTY PASSWORD when not speci‐
101 fied”.
102 Passwords
104 Passwords are interpreted in the following forms below using prefix
105 identifiers.
106 Note: By default passwords are assumed to be in the string form when
108 they do not have a prefix.
109 String
111 A string password, specified by prefix “str:” or it’s absence (raw
112 string without prefix) is not interpreted, and is directly used for au‐
113 thorization.
114 Examples
116 foobar
117 str:foobar
118 Hex-string
120 A hex-string password, specified by prefix “hex:” is converted from a
121 hexidecimal form into a byte array form, thus allowing passwords with
122 non-printable and/or terminal un-friendly characters.
123 Example
125 hex:0x1122334455667788
126 File
128 A file based password, specified be prefix “file:” should be the path
129 of a file containing the password to be read by the tool or a “-” to
130 use stdin. Storing passwords in files prevents information leakage,
131 passwords passed as options can be read from the process list or common
132 shell history features.
133 Examples
135 # to use stdin and be prompted
136 file:-
137 # to use a file from a path
139 file:path/to/password/file
140 # to echo a password via stdin:
142 echo foobar | tpm2_tool -p file:-
143 # to use a bash here-string via stdin:
145 tpm2_tool -p file:- <<< foobar
147 Sessions
149 When using a policy session to authorize the use of an object, prefix
150 the option argument with the session keyword. Then indicate a path to
151 a session file that was created with tpm2_startauthsession(1). Option‐
152 ally, if the session requires an auth value to be sent with the session
153 handle (eg policy password), then append a + and a string as described
154 in the Passwords section.
155 Examples
157 To use a session context file called session.ctx.
158 session:session.ctx
160 To use a session context file called session.ctx AND send the authvalue
162 mypassword.
163 session:session.ctx+mypassword
165 To use a session context file called session.ctx AND send the HEX auth‐
167 value 0x11223344.
168 session:session.ctx+hex:11223344
170 PCR Authorizations
172 You can satisfy a PCR policy using the “pcr:” prefix and the PCR mini‐
173 language. The PCR minilanguage is as follows:
174 <pcr-spec>=<raw-pcr-file>
175 The PCR spec is documented in in the section “PCR bank specifiers”.
177 The raw-pcr-file is an optional argument that contains the output of
179 the raw PCR contents as returned by tpm2_pcrread(1).
180 PCR bank specifiers (pcr.md)
182 Examples
184 To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifi‐
185 er of:
186 pcr:sha256:0,1,2,3
188 specifying AUTH.
190
192 Options that take algorithms support “nice-names”.
193 There are two major algorithm specification string classes, simple and
195 complex. Only certain algorithms will be accepted by the TPM, based on
196 usage and conditions.
197 Simple specifiers
199 These are strings with no additional specification data. When creating
200 objects, non-specified portions of an object are assumed to defaults.
201 You can find the list of known “Simple Specifiers Below”.
202 Asymmetric
204 • rsa
205 • ecc
207 Symmetric
209 • aes
210 • camellia
212 Hashing Algorithms
214 • sha1
215 • sha256
217 • sha384
219 • sha512
221 • sm3_256
223 • sha3_256
225 • sha3_384
227 • sha3_512
229 Keyed Hash
231 • hmac
232 • xor
234 Signing Schemes
236 • rsassa
237 • rsapss
239 • ecdsa
241 • ecdaa
243 • ecschnorr
245 Asymmetric Encryption Schemes
247 • oaep
248 • rsaes
250 • ecdh
252 Modes
254 • ctr
255 • ofb
257 • cbc
259 • cfb
261 • ecb
263 Misc
265 • null
266 Complex Specifiers
268 Objects, when specified for creation by the TPM, have numerous algo‐
269 rithms to populate in the public data. Things like type, scheme and
270 asymmetric details, key size, etc. Below is the general format for
271 specifying this data: <type>:<scheme>:<symmetric-details>
272 Type Specifiers
274 This portion of the complex algorithm specifier is required. The re‐
275 maining scheme and symmetric details will default based on the type
276 specified and the type of the object being created.
277 • aes - Default AES: aes128
279 • aes128<mode> - 128 bit AES with optional mode (ctr|ofb|cbc|cfb|ecb).
281 If mode is not specified, defaults to null.
282 • aes192<mode> - Same as aes128<mode>, except for a 192 bit key size.
284 • aes256<mode> - Same as aes128<mode>, except for a 256 bit key size.
286 • ecc - Elliptical Curve, defaults to ecc256.
288 • ecc192 - 192 bit ECC
290 • ecc224 - 224 bit ECC
292 • ecc256 - 256 bit ECC
294 • ecc384 - 384 bit ECC
296 • ecc521 - 521 bit ECC
298 • rsa - Default RSA: rsa2048
300 • rsa1024 - RSA with 1024 bit keysize.
302 • rsa2048 - RSA with 2048 bit keysize.
304 • rsa4096 - RSA with 4096 bit keysize.
306 Scheme Specifiers
308 Next, is an optional field, it can be skipped.
309 Schemes are usually Signing Schemes or Asymmetric Encryption Schemes.
311 Most signing schemes take a hash algorithm directly following the sign‐
312 ing scheme. If the hash algorithm is missing, it defaults to sha256.
313 Some take no arguments, and some take multiple arguments.
314 Hash Optional Scheme Specifiers
316 These scheme specifiers are followed by a dash and a valid hash algo‐
317 rithm, For example: oaep-sha256.
318 • oaep
320 • ecdh
322 • rsassa
324 • rsapss
326 • ecdsa
328 • ecschnorr
330 Multiple Option Scheme Specifiers
332 This scheme specifier is followed by a count (max size UINT16) then
333 followed by a dash(-) and a valid hash algorithm. * ecdaa For example,
334 ecdaa4-sha256. If no count is specified, it defaults to 4.
335 No Option Scheme Specifiers
337 This scheme specifier takes NO arguments. * rsaes
338 Symmetric Details Specifiers
340 This field is optional, and defaults based on the type of object being
341 created and it’s attributes. Generally, any valid Symmetric specifier
342 from the Type Specifiers list should work. If not specified, an asym‐
343 metric objects symmetric details defaults to aes128cfb.
344 Examples
346 Create an rsa2048 key with an rsaes asymmetric encryption scheme
347 tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv
348 Create an ecc256 key with an ecdaa signing scheme with a count of 4 and
350 sha384 hash
351 /tpm2_create -C parent.ctx -G ecc256:ecdaa4-sha384 -u key.pub -r
352 key.priv cryptographic algorithms ALGORITHM.
353
355 This collection of options are common to many programs and provide in‐
356 formation that many users may expect.
357 • -h, --help=[man|no-man]: Display the tools manpage. By default, it
359 attempts to invoke the manpager for the tool, however, on failure
360 will output a short tool summary. This is the same behavior if the
361 “man” option argument is specified, however if explicit “man” is re‐
362 quested, the tool will provide errors from man on stderr. If the
363 “no-man” option if specified, or the manpager fails, the short op‐
364 tions will be output to stdout.
365 To successfully use the manpages feature requires the manpages to be
367 installed or on MANPATH, See man(1) for more details.
368 • -v, --version: Display version information for this tool, supported
370 tctis and exit.
371 • -V, --verbose: Increase the information that the tool prints to the
373 console during its execution. When using this option the file and
374 line number are printed.
375 • -Q, --quiet: Silence normal tool output to stdout.
377 • -Z, --enable-errata: Enable the application of errata fixups. Useful
379 if an errata fixup needs to be applied to commands sent to the TPM.
380 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
381 formation many users may expect.
382
384 The TCTI or “Transmission Interface” is the communication mechanism
385 with the TPM. TCTIs can be changed for communication with TPMs across
386 different mediums.
387 To control the TCTI, the tools respect:
389 1. The command line option -T or --tcti
391 2. The environment variable: TPM2TOOLS_TCTI.
393 Note: The command line option always overrides the environment vari‐
395 able.
396 The current known TCTIs are:
398 • tabrmd - The resource manager, called tabrmd
400 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
401 abrmd as a tcti name are synonymous.
402 • mssim - Typically used for communicating to the TPM software simula‐
404 tor.
405 • device - Used when talking directly to a TPM device file.
407 • none - Do not initalize a connection with the TPM. Some tools allow
409 for off-tpm options and thus support not using a TCTI. Tools that do
410 not support it will error when attempted to be used without a TCTI
411 connection. Does not support ANY options and MUST BE presented as
412 the exact text of “none”.
413 The arguments to either the command line option or the environment
415 variable are in the form:
416 <tcti-name>:<tcti-option-config>
418 Specifying an empty string for either the <tcti-name> or <tcti-op‐
420 tion-config> results in the default being used for that portion respec‐
421 tively.
422 TCTI Defaults
424 When a TCTI is not specified, the default TCTI is searched for using
425 dlopen(3) semantics. The tools will search for tabrmd, device and
426 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
427 what TCTI will be chosen as the default by using the -v option to print
428 the version information. The “default-tcti” key-value pair will indi‐
429 cate which of the aforementioned TCTIs is the default.
430 Custom TCTIs
432 Any TCTI that implements the dynamic TCTI interface can be loaded. The
433 tools internally use dlopen(3), and the raw tcti-name value is used for
434 the lookup. Thus, this could be a path to the shared library, or a li‐
435 brary name as understood by dlopen(3) semantics.
436
438 This collection of options are used to configure the various known TCTI
439 modules available:
440 • device: For the device TCTI, the TPM character device file for use by
442 the device TCTI can be specified. The default is /dev/tpm0.
443 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI=“de‐
445 vice:/dev/tpm0”
446 • mssim: For the mssim TCTI, the domain name or IP address and port
448 number used by the simulator can be specified. The default are
449 127.0.0.1 and 2321.
450 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
452 TI=“mssim:host=localhost,port=2321”
453 • abrmd: For the abrmd TCTI, the configuration string format is a se‐
455 ries of simple key value pairs separated by a `,' character. Each
456 key and value string are separated by a `=' character.
457 • TCTI abrmd supports two keys:
459 1. `bus_name' : The name of the tabrmd service on the bus (a
461 string).
462 2. `bus_type' : The type of the dbus instance (a string) limited to
464 `session' and `system'.
465 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
467 ample.FooBar:
468 \--tcti=tabrmd:bus_name=com.example.FooBar
470 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
472 sion:
473 \--tcti:bus_type=session
475 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
477 ules.
478
480 Create an Endorsement Key and make it persistent
481 tpm2_createek -P abc123 -w abc123 -c 0x81010001 -G rsa -u ek.pub
482 Create a transient Endorsement Key, flush it, and reload it.
484 tpm2_createek -G rsa -u ek.pub
485 # Check that it is loaded in transient memory
487 tpm2_getcap handles-transient
488 - 0x80000000
489 # Flush the handle
491 tpm2_flushcontext 0x80000000
492 # Note that it is flushed
494 tpm2_getcap handles-transient
495 <null output>
496 # Reload it via loadexternal
498 tpm2_loadexternal -C o -u ek.pub -c ek.ctx
499 # Check that it is re-loaded in transient memory
501 tpm2_getcap handles-transient
502 - 0x80000000
503
505 Tools can return any of the following codes:
506 • 0 - Success.
508 • 1 - General non-specific error.
510 • 2 - Options handling error.
512 • 3 - Authentication error.
514 • 4 - TCTI related error.
516 • 5 - Non supported scheme. Applicable to tpm2_testparams.
518
520 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
521
523 See the Mailing List (https://lists.01.org/mailman/listinfo/tpm2)
524tpm2-tools tpm2_createek(1)