1tpm2_commit(1) General Commands Manual tpm2_commit(1)
2
6 tpm2_commit(1) - Performs the first part of an ECC anonymous signing
7 operation.
8
10 tpm2_commit [OPTIONS]
11
13 tpm2_commit(1) - Performs the first part of an ECC anonymous signing
14 operation. The TPM will perform the point multiplications on the pro‐
15 vided points and return intermediate signing values. The signing key
16 is an ECC key. The key cannot be a sign+decrypt key and must have an
17 anonymous signing scheme. TPM_ALG_ECDAA is the only supported anony‐
18 mous scheme.
19
21 • ARGUMENT=FILE:
22 Specify the input data used to derive the x coordinate of the base‐
24 point.
25 • --basepoint-y=FILE:
27 Specify the y coordinate of the basepoint.
29 • --eccpoint-P=FILE:
31 Specify a point on the curve used by sign handle.
33 • --eccpoint-K=FILE:
35 Output ECC point K ≔ [ds](x2, y2).
37 • --eccpoint-L=FILE:
39 Output ECC point L ≔ [r](x2, y2).
41 • -u, --public=FILE:
43 Output ECC point E ≔ [r]P1.
45 • -t, --counter=FILE
47 Specify file path to save the least-significant 16 bits of commit
49 count.
50 • -p, --auth=AUTH:
52 The authorization value for the created object.
54 • -c, --context=FILE:
56 Context object pointing to the the key used for signing. Either a
58 file or a handle number. See section “Context Object Format”.
59 • --cphash=FILE
61 File path to record the hash of the command parameters. This is com‐
63 monly termed as cpHash. NOTE: When this option is selected, The tool
64 will not actually execute the command, it simply returns a cpHash.
65 References
68 Options that take algorithms support “nice-names”.
69 There are two major algorithm specification string classes, simple and
71 complex. Only certain algorithms will be accepted by the TPM, based on
72 usage and conditions.
73 Simple specifiers
75 These are strings with no additional specification data. When creating
76 objects, non-specified portions of an object are assumed to defaults.
77 You can find the list of known “Simple Specifiers” below.
78 Asymmetric
80 • rsa
81 • ecc
83 Symmetric
85 • aes
86 • camellia
88 • sm4
90 Hashing Algorithms
92 • sha1
93 • sha256
95 • sha384
97 • sha512
99 • sm3_256
101 • sha3_256
103 • sha3_384
105 • sha3_512
107 Keyed Hash
109 • hmac
110 • xor
112 Signing Schemes
114 • rsassa
115 • rsapss
117 • ecdsa
119 • ecdaa
121 • ecschnorr
123 • sm2
125 Asymmetric Encryption Schemes
127 • oaep
128 • rsaes
130 • ecdh
132 Modes
134 • ctr
135 • ofb
137 • cbc
139 • cfb
141 • ecb
143 Misc
145 • null
146 Complex Specifiers
148 Objects, when specified for creation by the TPM, have numerous algo‐
149 rithms to populate in the public data. Things like type, scheme and
150 asymmetric details, key size, etc. Below is the general format for
151 specifying this data: <type>:<scheme>:<symmetric-details>
152 Type Specifiers
154 This portion of the complex algorithm specifier is required. The re‐
155 maining scheme and symmetric details will default based on the type
156 specified and the type of the object being created.
157 • aes - Default AES: aes128
159 • aes128<mode> - 128 bit AES with optional mode (ctr|ofb|cbc|cfb|ecb).
161 If mode is not specified, defaults to null.
162 • aes192<mode> - Same as aes128<mode>, except for a 192 bit key size.
164 • aes256<mode> - Same as aes128<mode>, except for a 256 bit key size.
166 • sm4 - Default SM4: sm4128
168 • sm4128 or sm4_128 <mode> - 128 bit SM4 with optional mode
170 (ctr|ofb|cbc|cfb|ecb). If mode is not specified, defaults to null.
171 • ecc - Elliptical Curve, defaults to ecc256.
173 • ecc192 or ecc_nist_p192 - 192 bit ECC NIST curve
175 • ecc224 or ecc_nist_p224 - 224 bit ECC NIST curve
177 • ecc256 or ecc_nist_p256 - 256 bit ECC NIST curve
179 • ecc384 or ecc_nist_p384 - 384 bit ECC NIST curve
181 • ecc521 or ecc_nist_p521 - 521 bit ECC NIST curve
183 • ecc_sm2 or ecc_sm2_p256 - 256 bit SM2 curve
185 • rsa - Default RSA: rsa2048
187 • rsa1024 - RSA with 1024 bit keysize.
189 • rsa2048 - RSA with 2048 bit keysize.
191 • rsa3072 - RSA with 3072 bit keysize.
193 • rsa4096 - RSA with 4096 bit keysize.
195 Scheme Specifiers
197 Next, is an optional field, it can be skipped.
198 Schemes are usually Signing Schemes or Asymmetric Encryption Schemes.
200 Most signing schemes take a hash algorithm directly following the sign‐
201 ing scheme. If the hash algorithm is missing, it defaults to sha256.
202 Some take no arguments, and some take multiple arguments.
203 Hash Optional Scheme Specifiers
205 These scheme specifiers are followed by a dash and a valid hash algo‐
206 rithm, For example: oaep-sha256.
207 • oaep
209 • ecdh
211 • rsassa
213 • rsapss
215 • ecdsa
217 • ecschnorr
219 • sm2
221 Multiple Option Scheme Specifiers
223 This scheme specifier is followed by a count (max size UINT16) then
224 followed by a dash(-) and a valid hash algorithm. * ecdaa For example,
225 ecdaa4-sha256. If no count is specified, it defaults to 4.
226 No Option Scheme Specifiers
228 This scheme specifier takes NO arguments. * rsaes
229 Symmetric Details Specifiers
231 This field is optional, and defaults based on the type of object being
232 created and it’s attributes. Generally, any valid Symmetric specifier
233 from the Type Specifiers list should work. If not specified, an asym‐
234 metric objects symmetric details defaults to aes128cfb.
235 Examples
237 Create an rsa2048 key with an rsaes asymmetric encryption scheme
238 tpm2_create -C parent.ctx -G rsa2048:rsaes -u key.pub -r key.priv
239 Create an ecc256 key with an ecdaa signing scheme with a count of 4 and
241 sha384 hash
242 /tpm2_create -C parent.ctx -G ecc256:ecdaa4-sha384 -u key.pub -r
243 key.priv cryptographic algorithms ALGORITHM.
244
246 This collection of options are common to many programs and provide in‐
247 formation that many users may expect.
248 • -h, --help=[man|no-man]: Display the tools manpage. By default, it
250 attempts to invoke the manpager for the tool, however, on failure
251 will output a short tool summary. This is the same behavior if the
252 “man” option argument is specified, however if explicit “man” is re‐
253 quested, the tool will provide errors from man on stderr. If the
254 “no-man” option if specified, or the manpager fails, the short op‐
255 tions will be output to stdout.
256 To successfully use the manpages feature requires the manpages to be
258 installed or on MANPATH, See man(1) for more details.
259 • -v, --version: Display version information for this tool, supported
261 tctis and exit.
262 • -V, --verbose: Increase the information that the tool prints to the
264 console during its execution. When using this option the file and
265 line number are printed.
266 • -Q, --quiet: Silence normal tool output to stdout.
268 • -Z, --enable-errata: Enable the application of errata fixups. Useful
270 if an errata fixup needs to be applied to commands sent to the TPM.
271 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
272 formation many users may expect.
273
275 The TCTI or “Transmission Interface” is the communication mechanism
276 with the TPM. TCTIs can be changed for communication with TPMs across
277 different mediums.
278 To control the TCTI, the tools respect:
280 1. The command line option -T or --tcti
282 2. The environment variable: TPM2TOOLS_TCTI.
284 Note: The command line option always overrides the environment vari‐
286 able.
287 The current known TCTIs are:
289 • tabrmd - The resource manager, called tabrmd
291 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
292 abrmd as a tcti name are synonymous.
293 • mssim - Typically used for communicating to the TPM software simula‐
295 tor.
296 • device - Used when talking directly to a TPM device file.
298 • none - Do not initalize a connection with the TPM. Some tools allow
300 for off-tpm options and thus support not using a TCTI. Tools that do
301 not support it will error when attempted to be used without a TCTI
302 connection. Does not support ANY options and MUST BE presented as
303 the exact text of “none”.
304 The arguments to either the command line option or the environment
306 variable are in the form:
307 <tcti-name>:<tcti-option-config>
309 Specifying an empty string for either the <tcti-name> or <tcti-op‐
311 tion-config> results in the default being used for that portion respec‐
312 tively.
313 TCTI Defaults
315 When a TCTI is not specified, the default TCTI is searched for using
316 dlopen(3) semantics. The tools will search for tabrmd, device and
317 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
318 what TCTI will be chosen as the default by using the -v option to print
319 the version information. The “default-tcti” key-value pair will indi‐
320 cate which of the aforementioned TCTIs is the default.
321 Custom TCTIs
323 Any TCTI that implements the dynamic TCTI interface can be loaded. The
324 tools internally use dlopen(3), and the raw tcti-name value is used for
325 the lookup. Thus, this could be a path to the shared library, or a li‐
326 brary name as understood by dlopen(3) semantics.
327
329 This collection of options are used to configure the various known TCTI
330 modules available:
331 • device: For the device TCTI, the TPM character device file for use by
333 the device TCTI can be specified. The default is /dev/tpm0.
334 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI=“de‐
336 vice:/dev/tpm0”
337 • mssim: For the mssim TCTI, the domain name or IP address and port
339 number used by the simulator can be specified. The default are
340 127.0.0.1 and 2321.
341 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
343 TI=“mssim:host=localhost,port=2321”
344 • abrmd: For the abrmd TCTI, the configuration string format is a se‐
346 ries of simple key value pairs separated by a `,' character. Each
347 key and value string are separated by a `=' character.
348 • TCTI abrmd supports two keys:
350 1. `bus_name' : The name of the tabrmd service on the bus (a
352 string).
353 2. `bus_type' : The type of the dbus instance (a string) limited to
355 `session' and `system'.
356 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
358 ample.FooBar:
359 \--tcti=tabrmd:bus_name=com.example.FooBar
361 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
363 sion:
364 \--tcti:bus_type=session
366 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
368 ules.
369
371 tpm2_createprimary -C o -c prim.ctx -Q
372 tpm2_create -C prim.ctx -c key.ctx -u key.pub -r key.priv -G ecc256:ecdaa
374 tpm2_commit -c key.ctx -t count.er \
376 --eccpoint-K K.bin --eccpoint-L L.bin -u E.bin
377
379 Tools can return any of the following codes:
380 • 0 - Success.
382 • 1 - General non-specific error.
384 • 2 - Options handling error.
386 • 3 - Authentication error.
388 • 4 - TCTI related error.
390 • 5 - Non supported scheme. Applicable to tpm2_testparams.
392
394 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
395
397 See the Mailing List (https://lists.linuxfoundation.org/mailman/listin‐
398 fo/tpm2)
399tpm2-tools tpm2_commit(1)