1tpm2_createek(1) General Commands Manual tpm2_createek(1)
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6 tpm2_createek(1) - Generate TCG profile compliant endorsement key.
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9 tpm2_createek [OPTIONS]
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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=FORMAT:
65 Public key format.
67 References
70 The type of a context object, whether it is a handle or file name, is
71 determined according to the following logic in-order:
72 · If the argument is a file path, then the file is loaded as a restored
74 TPM transient object.
75 · If the argument is a prefix match on one of:
77 · owner: the owner hierarchy
79 · platform: the platform hierarchy
81 · endorsement: the endorsement hierarchy
83 · lockout: the lockout control persistent object
85 · If the argument argument can be loaded as a number it will be treat
87 as a handle, e.g. 0x81010013 and used directly.OBJECT.
88
90 Authorization for use of an object in TPM2.0 can come in 3 different
91 forms: 1. Password 2. HMAC 3. Sessions
92 NOTE: "Authorizations default to the EMPTY PASSWORD when not speci‐
94 fied".
95 Passwords
97 Passwords are interpreted in the following forms below using prefix
98 identifiers.
99 Note: By default passwords are assumed to be in the string form when
101 they do not have a prefix.
102 String
104 A string password, specified by prefix "str:" or it's absence (raw
105 string without prefix) is not interpreted, and is directly used for au‐
106 thorization.
107 Examples
109 foobar
110 str:foobar
111 Hex-string
113 A hex-string password, specified by prefix "hex:" is converted from a
114 hexidecimal form into a byte array form, thus allowing passwords with
115 non-printable and/or terminal un-friendly characters.
116 Example
118 hex:0x1122334455667788
119 File
121 A file based password, specified be prefix "file:" should be the path
122 of a file containing the password to be read by the tool or a "-" to
123 use stdin. Storing passwords in files prevents information leakage,
124 passwords passed as options can be read from the process list or common
125 shell history features.
126 Examples
128 # to use stdin and be prompted
129 file:-
130 # to use a file from a path
132 file:path/to/password/file
133 # to echo a password via stdin:
135 echo foobar | tpm2_tool -p file:-
136 # to use a bash here-string via stdin:
138 tpm2_tool -p file:- <<< foobar
140 Sessions
142 When using a policy session to authorize the use of an object, prefix
143 the option argument with the session keyword. Then indicate a path to
144 a session file that was created with tpm2_startauthsession(1). Option‐
145 ally, if the session requires an auth value to be sent with the session
146 handle (eg policy password), then append a + and a string as described
147 in the Passwords section.
148 Examples
150 To use a session context file called session.ctx.
151 session:session.ctx
153 To use a session context file called session.ctx AND send the authvalue
155 mypassword.
156 session:session.ctx+mypassword
158 To use a session context file called session.ctx AND send the HEX auth‐
160 value 0x11223344.
161 session:session.ctx+hex:11223344
163 PCR Authorizations
165 You can satisfy a PCR policy using the "pcr:" prefix and the PCR mini‐
166 language. The PCR minilanguage is as follows:
167 <pcr-spec>=<raw-pcr-file>
168 The PCR spec is documented in in the section "PCR bank specifiers".
170 The raw-pcr-file is an optional the output of the raw PCR contents as
172 returned by tpm2_pcrread(1).
173 PCR bank specifiers (common/pcr.md)
175 Examples
177 To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifi‐
178 er of:
179 pcr:sha256:0,1,2,3
181 specifying AUTH.
183
185 Options that take algorithms support "nice-names".
186 There are two major algorithm specification string classes, simple and
188 complex. Only certain algorithms will be accepted by the TPM, based on
189 usage and conditions.
190 Simple specifiers
192 These are strings with no additional specification data. When creating
193 objects, non-specified portions of an object are assumed to defaults.
194 You can find the list of known "Simple Specifiers Below".
195 Asymmetric
197 · rsa
198 · ecc
200 Symmetric
202 · aes
203 · camellia
205 Hashing Algorithms
207 · sha1
208 · sha256
210 · sha384
212 · sha512
214 · sm3_256
216 · sha3_256
218 · sha3_384
220 · sha3_512
222 Keyed Hash
224 · hmac
225 · xor
227 Signing Schemes
229 · rsassa
230 · rsapss
232 · ecdsa
234 · ecdaa
236 · ecschnorr
238 Asymmetric Encryption Schemes
240 · oaep
241 · rsaes
243 · ecdh
245 Modes
247 · ctr
248 · ofb
250 · cbc
252 · cfb
254 · ecb
256 Misc
258 · null
259 Complex Specifiers
261 Objects, when specified for creation by the TPM, have numerous algo‐
262 rithms to populate in the public data. Things like type, scheme and
263 asymmetric details, key size, etc. Below is the general format for
264 specifying this data: <type>:<scheme>:<symmetric-details>
265 Type Specifiers
267 This portion of the complex algorithm specifier is required. The re‐
268 maining scheme and symmetric details will default based on the type
269 specified and the type of the object being created.
270 · aes - Default AES: aes128
272 · aes128<mode> - 128 bit AES with optional mode (ctr|ofb|cbc|cfb|ecb).
274 If mode is not specified, defaults to null.
275 · aes192<mode> - Same as aes128<mode>, except for a 192 bit key size.
277 · aes256<mode> - Same as aes128<mode>, except for a 256 bit key size.
279 · ecc - Elliptical Curve, defaults to ecc256.
281 · ecc192 - 192 bit ECC
283 · ecc224 - 224 bit ECC
285 · ecc256 - 256 bit ECC
287 · ecc384 - 384 bit ECC
289 · ecc521 - 521 bit ECC
291 · rsa - Default RSA: rsa2048
293 · rsa1024 - RSA with 1024 bit keysize.
295 · rsa2048 - RSA with 2048 bit keysize.
297 · rsa4096 - RSA with 4096 bit keysize.
299 Scheme Specifiers
301 Next, is an optional field, it can be skipped.
302 Schemes are usually Signing Schemes or Asymmetric Encryption Schemes.
304 Most signing schemes take a hash algorithm directly following the sign‐
305 ing scheme. If the hash algorithm is missing, it defaults to sha256.
306 Some take no arguments, and some take multiple arguments.
307 Hash Optional Scheme Specifiers
309 These scheme specifiers are followed by a dash and a valid hash algo‐
310 rithm, For example: oaep-sha256.
311 · oaep
313 · ecdh
315 · rsassa
317 · rsapss
319 · ecdsa
321 · ecschnorr
323 Multiple Option Scheme Specifiers
325 This scheme specifier is followed by a count (max size UINT16) then
326 folloed by a dash(-) and a valid hash algorithm. * ecdaa For example,
327 ecdaa4-sha256. If no count is specified, it defaults to 4.
328 No Option Scheme Specifiers
330 This scheme specifier takes NO arguments. * rsaes
331 Symmetric Details Specifiers
333 This field is optional, and defaults based on the type of object being
334 created and it's attributes. Generally, any valid Symmetric specifier
335 from the Type Specifiers list should work. If not specified, an asym‐
336 metric objects symmetric details defaults to aes128cfb.
337 Examples
339 Create an rsa2048 key with an rsaes asymmetric encryption scheme
340 tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv
341 Create an ecc256 key with an ecdaa signing scheme with a count of 4
343 and sha384 hash
344 /tpm2_create -C parent.ctx -G ecc256:ec‐
346 daa4-sha384 -u key.pub -r key.priv cryptographic algorithms ALGORITHM.
347
349 This collection of options are common to many programs and provide in‐
350 formation that many users may expect.
351 · -h, --help=[man|no-man]: Display the tools manpage. By default, it
353 attempts to invoke the manpager for the tool, however, on failure
354 will output a short tool summary. This is the same behavior if the
355 "man" option argument is specified, however if explicit "man" is re‐
356 quested, the tool will provide errors from man on stderr. If the
357 "no-man" option if specified, or the manpager fails, the short op‐
358 tions will be output to stdout.
359 To successfully use the manpages feature requires the manpages to be
361 installed or on MANPATH, See man(1) for more details.
362 · -v, --version: Display version information for this tool, supported
364 tctis and exit.
365 · -V, --verbose: Increase the information that the tool prints to the
367 console during its execution. When using this option the file and
368 line number are printed.
369 · -Q, --quiet: Silence normal tool output to stdout.
371 · -Z, --enable-errata: Enable the application of errata fixups. Useful
373 if an errata fixup needs to be applied to commands sent to the TPM.
374 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
375 formation many users may expect.
376
378 The TCTI or "Transmission Interface" is the communication mechanism
379 with the TPM. TCTIs can be changed for communication with TPMs across
380 different mediums.
381 To control the TCTI, the tools respect:
383 1. The command line option -T or --tcti
385 2. The environment variable: TPM2TOOLS_TCTI.
387 Note: The command line option always overrides the environment vari‐
389 able.
390 The current known TCTIs are:
392 · tabrmd - The resource manager, called tabrmd
394 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
395 abrmd as a tcti name are synonymous.
396 · mssim - Typically used for communicating to the TPM software simula‐
398 tor.
399 · device - Used when talking directly to a TPM device file.
401 · none - Do not initalize a connection with the TPM. Some tools allow
403 for off-tpm options and thus support not using a TCTI. Tools that do
404 not support it will error when attempted to be used without a TCTI
405 connection. Does not support ANY options and MUST BE presented as
406 the exact text of "none".
407 The arguments to either the command line option or the environment
409 variable are in the form:
410 <tcti-name>:<tcti-option-config>
412 Specifying an empty string for either the <tcti-name> or <tcti-op‐
414 tion-config> results in the default being used for that portion respec‐
415 tively.
416 TCTI Defaults
418 When a TCTI is not specified, the default TCTI is searched for using
419 dlopen(3) semantics. The tools will search for tabrmd, device and
420 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
421 what TCTI will be chosen as the default by using the -v option to print
422 the version information. The "default-tcti" key-value pair will indi‐
423 cate which of the aforementioned TCTIs is the default.
424 Custom TCTIs
426 Any TCTI that implements the dynamic TCTI interface can be loaded. The
427 tools internally use dlopen(3), and the raw tcti-name value is used for
428 the lookup. Thus, this could be a path to the shared library, or a li‐
429 brary name as understood by dlopen(3) semantics.
430
432 This collection of options are used to configure the various known TCTI
433 modules available:
434 · device: For the device TCTI, the TPM character device file for use by
436 the device TCTI can be specified. The default is /dev/tpm0.
437 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI="de‐
439 vice:/dev/tpm0"
440 · mssim: For the mssim TCTI, the domain name or IP address and port
442 number used by the simulator can be specified. The default are
443 127.0.0.1 and 2321.
444 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
446 TI="mssim:host=localhost,port=2321"
447 · abrmd: For the abrmd TCTI, the configuration string format is a se‐
449 ries of simple key value pairs separated by a ',' character. Each
450 key and value string are separated by a '=' character.
451 · TCTI abrmd supports two keys:
453 1. 'bus_name' : The name of the tabrmd service on the bus (a
455 string).
456 2. 'bus_type' : The type of the dbus instance (a string) limited to
458 'session' and 'system'.
459 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
461 ample.FooBar:
462 \--tcti=tabrmd:bus_name=com.example.FooBar
464 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
466 sion:
467 \--tcti:bus_type=session
469 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
471 ules.
472
474 Create an Endorsement Key and make it persistent
475 tpm2_createek -P abc123 -w abc123 -c 0x81010001 -G rsa -u ek.pub
476 Create a transient Endorsement Key, flush it, and reload it.
478 tpm2_createek -G rsa -u ek.pub
479 # Check that it is loaded in transient memory
481 tpm2_getcap handles-transient
482 - 0x80000000
483 # Flush the handle
485 tpm2_flushcontext 0x80000000
486 # Note that it is flushed
488 tpm2_getcap handles-transient
489 <null output>
490 # Reload it via loadexternal
492 tpm2_loadexternal -C o -u ek.pub -c ek.ctx
493 # Check that it is re-loaded in transient memory
495 tpm2_getcap handles-transient
496 - 0x80000000
497
499 Tools can return any of the following codes:
500 · 0 - Success.
502 · 1 - General non-specific error.
504 · 2 - Options handling error.
506 · 3 - Authentication error.
508 · 4 - TCTI related error.
510 · 5 - Non supported scheme. Applicable to tpm2_testparams.
512
514 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
515
517 See the Mailing List (https://lists.01.org/mailman/listinfo/tpm2)
518tpm2-tools tpm2_createek(1)