1tpm2_import(1) General Commands Manual tpm2_import(1)
2
6 tpm2_import(1) - Imports an external key into the tpm as a TPM managed
7 key object.
8
10 tpm2_import [OPTIONS]
11
13 tpm2_import(1) - Imports an external generated key as TPM managed key
14 object. It requires that the parent key object be a RSA key. Can also
15 import a TPM managed key object created by the tpm2_duplicate tool.
16
18 These options control the key importation process:
19 • -G, --key-algorithm=ALGORITHM:
21 The algorithm used by the key to be imported. Supports:
22 • aes - AES 128, 192 or 256 key.
24 • rsa - RSA 1024 or 2048 key.
26 • ecc - ECC NIST P192, P224, P256, P384 or P521 public and private
28 key.
29 • hmac - HMAC key.
31 • -g, --hash-algorithm=ALGORITHM:
33 The hash algorithm for generating the objects name. This is optional
35 and defaults to sha256 when not specified. Algorithms should follow
36 the “formatting standards”, see section “Algorithm Specifiers”. Al‐
37 so, see section “Supported Hash Algorithms” for a list of supported
38 hash algorithms.
39 • -i, --input=FILE:
41 Specifies the filename of the key to be imported. For AES keys, this
43 file is the raw key bytes. For assymetric keys in PEM or DER format.
44 A typical file is generated with openssl genrsa.
45 • -C, --parent-context=OBJECT:
47 The parent key object.
49 • -U, --parent-public=FILE:
51 Optional. Specifies the parent key public data file input. This can
53 be read with tpm2_readpublic(1) tool. If not specified, the tool in‐
54 vokes a tpm2_readpublic on the parent object.
55 • -k, --encryption-key=FILE:
57 Optional. Specifies the file containing the symmetric algorithm key
59 that was used for the inner wrapper. If the file is specified the
60 tool assumes the algorithm is AES 128 in CFB mode otherwise none.
61 • -r, --private=FILE:
63 Specifies the file path required to save the encrypted private por‐
65 tion of the object imported as key.
66 When importing a duplicated object this option specifies the file
68 containing the private portion of the object to be imported. # Pro‐
69 tection Details
70 Objects that can move outside of TPM need to be protected (confiden‐
72 tiality and integrity). For instance, transient objects require that
73 TPM protected data (key or seal material) be stored outside of the TPM.
74 This is seen in tools like tpm2_create(1), where the -r option outputs
75 this protected data. This blob contains the sensitive portions of the
76 object. The sensitive portions of the object are protected by the par‐
77 ent object, using the parent’s symmetric encryption details to encrypt
78 the sensitive data and HMAC it.
79 In-depth details can be found in sections 23 of:
81 • https://trustedcomputinggroup.org/wp-content/up‐
83 loads/TPM-Rev-2.0-Part-1-Architecture-01.38.pdf
84 Notably Figure 20, is relevant, even though it’s specifically referring
86 to duplication blobs, the process is identical.
87 If the output is from tpm2_duplicate(1), the output will be slightly
89 different, as described fully in section 23.
90 • -u, --public=FILE:
92 Specifies the file path required to save the public portion of the
94 object imported as key
95 When importing a duplicated object this option specifies the file
97 containing the public portion of the object to be imported.
98 • -a, --attributes=ATTRIBUTES:
100 The object attributes, optional.
102 • -P, --parent-auth=AUTH:
104 The authorization value for using the parent key specified with -C.
106 • -p, --key-auth=AUTH:
108 The authorization value for the imported key, optional.
110 • -L, --policy=POLICY_FILE:
112 The policy file.
114 • -s, --seed=FILE:
116 Specifies the file containing the encrypted seed of the duplicated
118 object.
119 • --passin=OSSL_PEM_FILE_PASSWORD
121 An optional password for an Open SSL (OSSL) provided input file. It
123 mirrors the -passin option of OSSL and is known to support the pass,
124 file, env, fd and plain password formats of openssl. (see man(1)
125 openssl) for more.
126 • --cphash=FILE
128 File path to record the hash of the command parameters. This is com‐
130 monly termed as cpHash. NOTE: When this option is selected, The tool
131 will not actually execute the command, it simply returns a cpHash.
132 References
135 The type of a context object, whether it is a handle or file name, is
136 determined according to the following logic in-order:
137 • If the argument is a file path, then the file is loaded as a restored
139 TPM transient object.
140 • If the argument is a prefix match on one of:
142 • owner: the owner hierarchy
144 • platform: the platform hierarchy
146 • endorsement: the endorsement hierarchy
148 • lockout: the lockout control persistent object
150 • If the argument argument can be loaded as a number it will be treat
152 as a handle, e.g. 0x81010013 and used directly._OBJECT_.
153
155 Authorization for use of an object in TPM2.0 can come in 3 different
156 forms: 1. Password 2. HMAC 3. Sessions
157 NOTE: “Authorizations default to the EMPTY PASSWORD when not speci‐
159 fied”.
160 Passwords
162 Passwords are interpreted in the following forms below using prefix
163 identifiers.
164 Note: By default passwords are assumed to be in the string form when
166 they do not have a prefix.
167 String
169 A string password, specified by prefix “str:” or it’s absence (raw
170 string without prefix) is not interpreted, and is directly used for au‐
171 thorization.
172 Examples
174 foobar
175 str:foobar
176 Hex-string
178 A hex-string password, specified by prefix “hex:” is converted from a
179 hexidecimal form into a byte array form, thus allowing passwords with
180 non-printable and/or terminal un-friendly characters.
181 Example
183 hex:0x1122334455667788
184 File
186 A file based password, specified be prefix “file:” should be the path
187 of a file containing the password to be read by the tool or a “-” to
188 use stdin. Storing passwords in files prevents information leakage,
189 passwords passed as options can be read from the process list or common
190 shell history features.
191 Examples
193 # to use stdin and be prompted
194 file:-
195 # to use a file from a path
197 file:path/to/password/file
198 # to echo a password via stdin:
200 echo foobar | tpm2_tool -p file:-
201 # to use a bash here-string via stdin:
203 tpm2_tool -p file:- <<< foobar
205 Sessions
207 When using a policy session to authorize the use of an object, prefix
208 the option argument with the session keyword. Then indicate a path to
209 a session file that was created with tpm2_startauthsession(1). Option‐
210 ally, if the session requires an auth value to be sent with the session
211 handle (eg policy password), then append a + and a string as described
212 in the Passwords section.
213 Examples
215 To use a session context file called session.ctx.
216 session:session.ctx
218 To use a session context file called session.ctx AND send the authvalue
220 mypassword.
221 session:session.ctx+mypassword
223 To use a session context file called session.ctx AND send the HEX auth‐
225 value 0x11223344.
226 session:session.ctx+hex:11223344
228 PCR Authorizations
230 You can satisfy a PCR policy using the “pcr:” prefix and the PCR mini‐
231 language. The PCR minilanguage is as follows:
232 <pcr-spec>=<raw-pcr-file>
233 The PCR spec is documented in in the section “PCR bank specifiers”.
235 The raw-pcr-file is an optional argument that contains the output of
237 the raw PCR contents as returned by tpm2_pcrread(1).
238 PCR bank specifiers (pcr.md)
240 Examples
242 To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifi‐
243 er of:
244 pcr:sha256:0,1,2,3
246 specifying AUTH.
248
250 Options that take algorithms support “nice-names”.
251 There are two major algorithm specification string classes, simple and
253 complex. Only certain algorithms will be accepted by the TPM, based on
254 usage and conditions.
255 Simple specifiers
257 These are strings with no additional specification data. When creating
258 objects, non-specified portions of an object are assumed to defaults.
259 You can find the list of known “Simple Specifiers Below”.
260 Asymmetric
262 • rsa
263 • ecc
265 Symmetric
267 • aes
268 • camellia
270 Hashing Algorithms
272 • sha1
273 • sha256
275 • sha384
277 • sha512
279 • sm3_256
281 • sha3_256
283 • sha3_384
285 • sha3_512
287 Keyed Hash
289 • hmac
290 • xor
292 Signing Schemes
294 • rsassa
295 • rsapss
297 • ecdsa
299 • ecdaa
301 • ecschnorr
303 Asymmetric Encryption Schemes
305 • oaep
306 • rsaes
308 • ecdh
310 Modes
312 • ctr
313 • ofb
315 • cbc
317 • cfb
319 • ecb
321 Misc
323 • null
324 Complex Specifiers
326 Objects, when specified for creation by the TPM, have numerous algo‐
327 rithms to populate in the public data. Things like type, scheme and
328 asymmetric details, key size, etc. Below is the general format for
329 specifying this data: <type>:<scheme>:<symmetric-details>
330 Type Specifiers
332 This portion of the complex algorithm specifier is required. The re‐
333 maining scheme and symmetric details will default based on the type
334 specified and the type of the object being created.
335 • aes - Default AES: aes128
337 • aes128<mode> - 128 bit AES with optional mode (ctr|ofb|cbc|cfb|ecb).
339 If mode is not specified, defaults to null.
340 • aes192<mode> - Same as aes128<mode>, except for a 192 bit key size.
342 • aes256<mode> - Same as aes128<mode>, except for a 256 bit key size.
344 • ecc - Elliptical Curve, defaults to ecc256.
346 • ecc192 - 192 bit ECC
348 • ecc224 - 224 bit ECC
350 • ecc256 - 256 bit ECC
352 • ecc384 - 384 bit ECC
354 • ecc521 - 521 bit ECC
356 • rsa - Default RSA: rsa2048
358 • rsa1024 - RSA with 1024 bit keysize.
360 • rsa2048 - RSA with 2048 bit keysize.
362 • rsa4096 - RSA with 4096 bit keysize.
364 Scheme Specifiers
366 Next, is an optional field, it can be skipped.
367 Schemes are usually Signing Schemes or Asymmetric Encryption Schemes.
369 Most signing schemes take a hash algorithm directly following the sign‐
370 ing scheme. If the hash algorithm is missing, it defaults to sha256.
371 Some take no arguments, and some take multiple arguments.
372 Hash Optional Scheme Specifiers
374 These scheme specifiers are followed by a dash and a valid hash algo‐
375 rithm, For example: oaep-sha256.
376 • oaep
378 • ecdh
380 • rsassa
382 • rsapss
384 • ecdsa
386 • ecschnorr
388 Multiple Option Scheme Specifiers
390 This scheme specifier is followed by a count (max size UINT16) then
391 followed by a dash(-) and a valid hash algorithm. * ecdaa For example,
392 ecdaa4-sha256. If no count is specified, it defaults to 4.
393 No Option Scheme Specifiers
395 This scheme specifier takes NO arguments. * rsaes
396 Symmetric Details Specifiers
398 This field is optional, and defaults based on the type of object being
399 created and it’s attributes. Generally, any valid Symmetric specifier
400 from the Type Specifiers list should work. If not specified, an asym‐
401 metric objects symmetric details defaults to aes128cfb.
402 Examples
404 Create an rsa2048 key with an rsaes asymmetric encryption scheme
405 tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv
406 Create an ecc256 key with an ecdaa signing scheme with a count of 4 and
408 sha384 hash
409 /tpm2_create -C parent.ctx -G ecc256:ecdaa4-sha384 -u key.pub -r
410 key.priv cryptographic algorithms ALGORITHM.
411
413 Object Attributes are used to control various properties of created ob‐
414 jects. When specified as an option, either the raw bitfield mask or
415 “nice-names” may be used. The values can be found in Table 31 Part 2
416 of the TPM2.0 specification, which can be found here:
417 <https://trustedcomputinggroup.org/wp-content/uploads/TPM-
419 Rev-2.0-Part-2-Structures-01.38.pdf>
420 Nice names are calculated by taking the name field of table 31 and re‐
422 moving the prefix TPMA_OBJECT_ and lowercasing the result. Thus, TP‐
423 MA_OBJECT_FIXEDTPM becomes fixedtpm. Nice names can be joined using
424 the bitwise or “|” symbol.
425 For instance, to set The fields TPMA_OBJECT_FIXEDTPM, TPMA_OBJECT_NODA,
427 and TPMA_OBJECT_SIGN_ENCRYPT, the argument would be:
428 fixedtpm|noda|sign specifying the object attributes ATTRIBUTES.
430
432 This collection of options are common to many programs and provide in‐
433 formation that many users may expect.
434 • -h, --help=[man|no-man]: Display the tools manpage. By default, it
436 attempts to invoke the manpager for the tool, however, on failure
437 will output a short tool summary. This is the same behavior if the
438 “man” option argument is specified, however if explicit “man” is re‐
439 quested, the tool will provide errors from man on stderr. If the
440 “no-man” option if specified, or the manpager fails, the short op‐
441 tions will be output to stdout.
442 To successfully use the manpages feature requires the manpages to be
444 installed or on MANPATH, See man(1) for more details.
445 • -v, --version: Display version information for this tool, supported
447 tctis and exit.
448 • -V, --verbose: Increase the information that the tool prints to the
450 console during its execution. When using this option the file and
451 line number are printed.
452 • -Q, --quiet: Silence normal tool output to stdout.
454 • -Z, --enable-errata: Enable the application of errata fixups. Useful
456 if an errata fixup needs to be applied to commands sent to the TPM.
457 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
458 formation many users may expect.
459
461 The TCTI or “Transmission Interface” is the communication mechanism
462 with the TPM. TCTIs can be changed for communication with TPMs across
463 different mediums.
464 To control the TCTI, the tools respect:
466 1. The command line option -T or --tcti
468 2. The environment variable: TPM2TOOLS_TCTI.
470 Note: The command line option always overrides the environment vari‐
472 able.
473 The current known TCTIs are:
475 • tabrmd - The resource manager, called tabrmd
477 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
478 abrmd as a tcti name are synonymous.
479 • mssim - Typically used for communicating to the TPM software simula‐
481 tor.
482 • device - Used when talking directly to a TPM device file.
484 • none - Do not initalize a connection with the TPM. Some tools allow
486 for off-tpm options and thus support not using a TCTI. Tools that do
487 not support it will error when attempted to be used without a TCTI
488 connection. Does not support ANY options and MUST BE presented as
489 the exact text of “none”.
490 The arguments to either the command line option or the environment
492 variable are in the form:
493 <tcti-name>:<tcti-option-config>
495 Specifying an empty string for either the <tcti-name> or <tcti-op‐
497 tion-config> results in the default being used for that portion respec‐
498 tively.
499 TCTI Defaults
501 When a TCTI is not specified, the default TCTI is searched for using
502 dlopen(3) semantics. The tools will search for tabrmd, device and
503 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
504 what TCTI will be chosen as the default by using the -v option to print
505 the version information. The “default-tcti” key-value pair will indi‐
506 cate which of the aforementioned TCTIs is the default.
507 Custom TCTIs
509 Any TCTI that implements the dynamic TCTI interface can be loaded. The
510 tools internally use dlopen(3), and the raw tcti-name value is used for
511 the lookup. Thus, this could be a path to the shared library, or a li‐
512 brary name as understood by dlopen(3) semantics.
513
515 This collection of options are used to configure the various known TCTI
516 modules available:
517 • device: For the device TCTI, the TPM character device file for use by
519 the device TCTI can be specified. The default is /dev/tpm0.
520 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI=“de‐
522 vice:/dev/tpm0”
523 • mssim: For the mssim TCTI, the domain name or IP address and port
525 number used by the simulator can be specified. The default are
526 127.0.0.1 and 2321.
527 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
529 TI=“mssim:host=localhost,port=2321”
530 • abrmd: For the abrmd TCTI, the configuration string format is a se‐
532 ries of simple key value pairs separated by a `,' character. Each
533 key and value string are separated by a `=' character.
534 • TCTI abrmd supports two keys:
536 1. `bus_name' : The name of the tabrmd service on the bus (a
538 string).
539 2. `bus_type' : The type of the dbus instance (a string) limited to
541 `session' and `system'.
542 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
544 ample.FooBar:
545 \--tcti=tabrmd:bus_name=com.example.FooBar
547 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
549 sion:
550 \--tcti:bus_type=session
552 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
554 ules.
555
557 To import a key, one needs to have a parent key
558 tpm2_createprimary -Grsa2048:aes128cfb -C o -c parent.ctx
559 Create your key and and import it. If you already have a key, just use
561 that and skip creating it.
562 Import an AES 128 key
564 dd if=/dev/urandom of=sym.key bs=1 count=16
565 tpm2_import -C parent.ctx -G aes -i sym.key -u key.pub -r key.priv
567 Import an RSA key
569 openssl genrsa -out private.pem 2048
570 tpm2_import -C parent.ctx -G rsa -i private.pem -u key.pub -r key.priv
572 Import an ECC key
574 openssl ecparam -name prime256v1 -genkey -noout -out private.ecc.pem
575 tpm2_import -C parent.ctx -G ecc -i private.ecc.pem -u key.pub -r key.priv
577 Import a duplicated key
579 tpm2_import -C parent.ctx -i key.dup -u key.pub -r key.priv -L policy.dat
580
582 • The TPM requires that the name algorithm of the child be smaller than
583 the parent.
584
586 Tools can return any of the following codes:
587 • 0 - Success.
589 • 1 - General non-specific error.
591 • 2 - Options handling error.
593 • 3 - Authentication error.
595 • 4 - TCTI related error.
597 • 5 - Non supported scheme. Applicable to tpm2_testparams.
599
601 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
602
604 See the Mailing List (https://lists.01.org/mailman/listinfo/tpm2)
605tpm2-tools tpm2_import(1)