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]
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 · -p, --ek-auth=AUTH:
27 The authorization value for the primary object (endorsement key) cre‐
29 ated.
30 · -w, --owner-auth=AUTH
32 The authorization value for the owner hierarchy.
34 · -c, --ek-context=OBJECT or FILE:
36 Either a file path or a persistent handle value to save the endorse‐
38 ment key.
39 If a value of - is passed the tool will find a vacant persistent han‐
41 dle to use and print out the automatically selected handle.
42 If one saves the context file via this option and the public key via
44 the -u option, the EK can be restored via a call to tpm2_loadexter‐
45 nal(1).
46 · -G, --key-algorithm=ALGORITHM:
48 The endorsement key algorithm. Supports:
49 · ecc - An P256 key.
51 · rsa - An RSA2048 key.
53 · keyedhash - hmac key.
55 · -u, --public=FILE:
57 The optional input for a file to save the public portion of endorse‐
59 ment key.
60 · -t, --template=FILE:
62 The optional manufacturer defined endorsement key template and nonce
64 from fixed NV Indices to populate the TPM2B_PUBLIC public area. See
65 the TCG EK Credential Profile specification for more information:
66 https://trustedcomputinggroup.org/wp-content/uploads/ TCG_IWG_Creden‐
67 tial_Profile_EK_V2.1_R13.pdf
68 · -f, --format=FORMAT:
70 Public key format.
72 References
75 The type of a context object, whether it is a handle or file name, is
76 determined according to the following logic in-order:
77 · If the argument is a file path, then the file is loaded as a restored
79 TPM transient object.
80 · If the argument is a prefix match on one of:
82 · owner: the owner hierarchy
84 · platform: the platform hierarchy
86 · endorsement: the endorsement hierarchy
88 · lockout: the lockout control persistent object
90 · If the argument argument can be loaded as a number it will be treat
92 as a handle, e.g. 0x81010013 and used directly.OBJECT.
93
95 Authorization for use of an object in TPM2.0 can come in 3 different
96 forms: 1. Password 2. HMAC 3. Sessions
97 NOTE: "Authorizations default to the EMPTY PASSWORD when not speci‐
99 fied".
100 Passwords
102 Passwords are interpreted in the following forms below using prefix
103 identifiers.
104 Note: By default passwords are assumed to be in the string form when
106 they do not have a prefix.
107 String
109 A string password, specified by prefix "str:" or it's absence (raw
110 string without prefix) is not interpreted, and is directly used for au‐
111 thorization.
112 Examples
114 foobar
115 str:foobar
116 Hex-string
118 A hex-string password, specified by prefix "hex:" is converted from a
119 hexidecimal form into a byte array form, thus allowing passwords with
120 non-printable and/or terminal un-friendly characters.
121 Example
123 hex:0x1122334455667788
124 File
126 A file based password, specified be prefix "file:" should be the path
127 of a file containing the password to be read by the tool or a "-" to
128 use stdin. Storing passwords in files prevents information leakage,
129 passwords passed as options can be read from the process list or common
130 shell history features.
131 Examples
133 # to use stdin and be prompted
134 file:-
135 # to use a file from a path
137 file:path/to/password/file
138 # to echo a password via stdin:
140 echo foobar | tpm2_tool -p file:-
141 # to use a bash here-string via stdin:
143 tpm2_tool -p file:- <<< foobar
145 Sessions
147 When using a policy session to authorize the use of an object, prefix
148 the option argument with the session keyword. Then indicate a path to
149 a session file that was created with tpm2_startauthsession(1). Option‐
150 ally, if the session requires an auth value to be sent with the session
151 handle (eg policy password), then append a + and a string as described
152 in the Passwords section.
153 Examples
155 To use a session context file called session.ctx.
156 session:session.ctx
158 To use a session context file called session.ctx AND send the authvalue
160 mypassword.
161 session:session.ctx+mypassword
163 To use a session context file called session.ctx AND send the HEX auth‐
165 value 0x11223344.
166 session:session.ctx+hex:11223344
168 PCR Authorizations
170 You can satisfy a PCR policy using the "pcr:" prefix and the PCR mini‐
171 language. The PCR minilanguage is as follows:
172 <pcr-spec>=<raw-pcr-file>
173 The PCR spec is documented in in the section "PCR bank specifiers".
175 The raw-pcr-file is an optional the output of the raw PCR contents as
177 returned by tpm2_pcrread(1).
178 PCR bank specifiers (common/pcr.md)
180 Examples
182 To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifi‐
183 er of:
184 pcr:sha256:0,1,2,3
186 specifying AUTH.
188
190 Options that take algorithms support "nice-names".
191 There are two major algorithm specification string classes, simple and
193 complex. Only certain algorithms will be accepted by the TPM, based on
194 usage and conditions.
195 Simple specifiers
197 These are strings with no additional specification data. When creating
198 objects, non-specified portions of an object are assumed to defaults.
199 You can find the list of known "Simple Specifiers Below".
200 Asymmetric
202 · rsa
203 · ecc
205 Symmetric
207 · aes
208 · camellia
210 Hashing Algorithms
212 · sha1
213 · sha256
215 · sha384
217 · sha512
219 · sm3_256
221 · sha3_256
223 · sha3_384
225 · sha3_512
227 Keyed Hash
229 · hmac
230 · xor
232 Signing Schemes
234 · rsassa
235 · rsapss
237 · ecdsa
239 · ecdaa
241 · ecschnorr
243 Asymmetric Encryption Schemes
245 · oaep
246 · rsaes
248 · ecdh
250 Modes
252 · ctr
253 · ofb
255 · cbc
257 · cfb
259 · ecb
261 Misc
263 · null
264 Complex Specifiers
266 Objects, when specified for creation by the TPM, have numerous algo‐
267 rithms to populate in the public data. Things like type, scheme and
268 asymmetric details, key size, etc. Below is the general format for
269 specifying this data: <type>:<scheme>:<symmetric-details>
270 Type Specifiers
272 This portion of the complex algorithm specifier is required. The re‐
273 maining scheme and symmetric details will default based on the type
274 specified and the type of the object being created.
275 · aes - Default AES: aes128
277 · aes128<mode> - 128 bit AES with optional mode (ctr|ofb|cbc|cfb|ecb).
279 If mode is not specified, defaults to null.
280 · aes192<mode> - Same as aes128<mode>, except for a 192 bit key size.
282 · aes256<mode> - Same as aes128<mode>, except for a 256 bit key size.
284 · ecc - Elliptical Curve, defaults to ecc256.
286 · ecc192 - 192 bit ECC
288 · ecc224 - 224 bit ECC
290 · ecc256 - 256 bit ECC
292 · ecc384 - 384 bit ECC
294 · ecc521 - 521 bit ECC
296 · rsa - Default RSA: rsa2048
298 · rsa1024 - RSA with 1024 bit keysize.
300 · rsa2048 - RSA with 2048 bit keysize.
302 · rsa4096 - RSA with 4096 bit keysize.
304 Scheme Specifiers
306 Next, is an optional field, it can be skipped.
307 Schemes are usually Signing Schemes or Asymmetric Encryption Schemes.
309 Most signing schemes take a hash algorithm directly following the sign‐
310 ing scheme. If the hash algorithm is missing, it defaults to sha256.
311 Some take no arguments, and some take multiple arguments.
312 Hash Optional Scheme Specifiers
314 These scheme specifiers are followed by a dash and a valid hash algo‐
315 rithm, For example: oaep-sha256.
316 · oaep
318 · ecdh
320 · rsassa
322 · rsapss
324 · ecdsa
326 · ecschnorr
328 Multiple Option Scheme Specifiers
330 This scheme specifier is followed by a count (max size UINT16) then
331 folloed by a dash(-) and a valid hash algorithm. * ecdaa For example,
332 ecdaa4-sha256. If no count is specified, it defaults to 4.
333 No Option Scheme Specifiers
335 This scheme specifier takes NO arguments. * rsaes
336 Symmetric Details Specifiers
338 This field is optional, and defaults based on the type of object being
339 created and it's attributes. Generally, any valid Symmetric specifier
340 from the Type Specifiers list should work. If not specified, an asym‐
341 metric objects symmetric details defaults to aes128cfb.
342 Examples
344 Create an rsa2048 key with an rsaes asymmetric encryption scheme
345 tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv
346 Create an ecc256 key with an ecdaa signing scheme with a count of 4
348 and sha384 hash
349 /tpm2_create -C parent.ctx -G ecc256:ec‐
351 daa4-sha384 -u key.pub -r key.priv cryptographic algorithms ALGORITHM.
352
354 This collection of options are common to many programs and provide in‐
355 formation that many users may expect.
356 · -h, --help=[man|no-man]: Display the tools manpage. By default, it
358 attempts to invoke the manpager for the tool, however, on failure
359 will output a short tool summary. This is the same behavior if the
360 "man" option argument is specified, however if explicit "man" is re‐
361 quested, the tool will provide errors from man on stderr. If the
362 "no-man" option if specified, or the manpager fails, the short op‐
363 tions will be output to stdout.
364 To successfully use the manpages feature requires the manpages to be
366 installed or on MANPATH, See man(1) for more details.
367 · -v, --version: Display version information for this tool, supported
369 tctis and exit.
370 · -V, --verbose: Increase the information that the tool prints to the
372 console during its execution. When using this option the file and
373 line number are printed.
374 · -Q, --quiet: Silence normal tool output to stdout.
376 · -Z, --enable-errata: Enable the application of errata fixups. Useful
378 if an errata fixup needs to be applied to commands sent to the TPM.
379 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
380 formation many users may expect.
381
383 The TCTI or "Transmission Interface" is the communication mechanism
384 with the TPM. TCTIs can be changed for communication with TPMs across
385 different mediums.
386 To control the TCTI, the tools respect:
388 1. The command line option -T or --tcti
390 2. The environment variable: TPM2TOOLS_TCTI.
392 Note: The command line option always overrides the environment vari‐
394 able.
395 The current known TCTIs are:
397 · tabrmd - The resource manager, called tabrmd
399 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
400 abrmd as a tcti name are synonymous.
401 · mssim - Typically used for communicating to the TPM software simula‐
403 tor.
404 · device - Used when talking directly to a TPM device file.
406 · none - Do not initalize a connection with the TPM. Some tools allow
408 for off-tpm options and thus support not using a TCTI. Tools that do
409 not support it will error when attempted to be used without a TCTI
410 connection. Does not support ANY options and MUST BE presented as
411 the exact text of "none".
412 The arguments to either the command line option or the environment
414 variable are in the form:
415 <tcti-name>:<tcti-option-config>
417 Specifying an empty string for either the <tcti-name> or <tcti-op‐
419 tion-config> results in the default being used for that portion respec‐
420 tively.
421 TCTI Defaults
423 When a TCTI is not specified, the default TCTI is searched for using
424 dlopen(3) semantics. The tools will search for tabrmd, device and
425 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
426 what TCTI will be chosen as the default by using the -v option to print
427 the version information. The "default-tcti" key-value pair will indi‐
428 cate which of the aforementioned TCTIs is the default.
429 Custom TCTIs
431 Any TCTI that implements the dynamic TCTI interface can be loaded. The
432 tools internally use dlopen(3), and the raw tcti-name value is used for
433 the lookup. Thus, this could be a path to the shared library, or a li‐
434 brary name as understood by dlopen(3) semantics.
435
437 This collection of options are used to configure the various known TCTI
438 modules available:
439 · device: For the device TCTI, the TPM character device file for use by
441 the device TCTI can be specified. The default is /dev/tpm0.
442 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI="de‐
444 vice:/dev/tpm0"
445 · mssim: For the mssim TCTI, the domain name or IP address and port
447 number used by the simulator can be specified. The default are
448 127.0.0.1 and 2321.
449 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
451 TI="mssim:host=localhost,port=2321"
452 · abrmd: For the abrmd TCTI, the configuration string format is a se‐
454 ries of simple key value pairs separated by a ',' character. Each
455 key and value string are separated by a '=' character.
456 · TCTI abrmd supports two keys:
458 1. 'bus_name' : The name of the tabrmd service on the bus (a
460 string).
461 2. 'bus_type' : The type of the dbus instance (a string) limited to
463 'session' and 'system'.
464 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
466 ample.FooBar:
467 \--tcti=tabrmd:bus_name=com.example.FooBar
469 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
471 sion:
472 \--tcti:bus_type=session
474 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
476 ules.
477
479 Create an Endorsement Key and make it persistent
480 tpm2_createek -P abc123 -w abc123 -p passwd -c 0x81010001 -G rsa -u ek.pub
481 Create a transient Endorsement Key, flush it, and reload it.
483 tpm2_createek -G rsa -u ek.pub
484 # Check that it is loaded in transient memory
486 tpm2_getcap handles-transient
487 - 0x80000000
488 # Flush the handle
490 tpm2_flushcontext 0x80000000
491 # Note that it is flushed
493 tpm2_getcap handles-transient
494 <null output>
495 # Reload it via loadexternal
497 tpm2_loadexternal -C o -u ek.pub -c ek.ctx
498 # Check that it is re-loaded in transient memory
500 tpm2_getcap handles-transient
501 - 0x80000000
502
504 Tools can return any of the following codes:
505 · 0 - Success.
507 · 1 - General non-specific error.
509 · 2 - Options handling error.
511 · 3 - Authentication error.
513 · 4 - TCTI related error.
515 · 5 - Non supported scheme. Applicable to tpm2_testparams.
517
519 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
520
522 See the Mailing List (https://lists.01.org/mailman/listinfo/tpm2)
523tpm2-tools tpm2_createek(1)