1tpm2_policylocality(1) General Commands Manual tpm2_policylocality(1)
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6 tpm2_policylocality(1) - Restrict TPM object authorization to specific
7 localities.
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10 tpm2_policylocality [OPTIONS] [ARGUMENT]
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13 tpm2_policylocality(1) - Restricts TPM object authorization to specific
14 TPM locality. Useful when you want to allow only specific locality
15 with the TPM object. A locality indicates the source of the command,
16 for example it could be from the application layer or the driver layer,
17 each would have it’s own locality integer. Localities are hints to the
18 TPM and are enforced by the software communicating to the TPM. Thus
19 they are not trusted inputs on their own and are implemented in plat‐
20 form specific ways.
21 As an argument it takes the LOCALITY as an integer or friendly name.
23 Localities are fixed to a byte in size and have two representations,
25 locality and extended locality.
26 Localities 0 through 4 are the normal locality representation and are
28 represented as set bit indexes. Thus locality 0 is indicated by 1<<0
29 and locality 4 is indicated by 1<<4. Rather then using raw numbers,
30 these localities can also be specified by the friendly names of: - ze‐
31 ro: locality 0 or 1<<0 - one: locality 1 or 1<<1 - two: locality 2 or
32 1<<2 - three: locality 3 or 1<<3 - four: locality 4 or 1<<4
33 Anything from the range 32 - 255 are extended localities.
35
37 • -S, --session=FILE:
38 A session file from tpm2_startauthsession(1)’s -S option.
40 • -L, --policy=FILE:
42 File to save the policy digest.
44 • ARGUMENT the command line argument specifies the locality number.
46 • --cphash=FILE
48 File path to record the hash of the command parameters. This is com‐
50 monly termed as cpHash. NOTE: When this option is selected, The tool
51 will not actually execute the command, it simply returns a cpHash.
52 References
55 This collection of options are common to many programs and provide in‐
56 formation that many users may expect.
57 • -h, --help=[man|no-man]: Display the tools manpage. By default, it
59 attempts to invoke the manpager for the tool, however, on failure
60 will output a short tool summary. This is the same behavior if the
61 “man” option argument is specified, however if explicit “man” is re‐
62 quested, the tool will provide errors from man on stderr. If the
63 “no-man” option if specified, or the manpager fails, the short op‐
64 tions will be output to stdout.
65 To successfully use the manpages feature requires the manpages to be
67 installed or on MANPATH, See man(1) for more details.
68 • -v, --version: Display version information for this tool, supported
70 tctis and exit.
71 • -V, --verbose: Increase the information that the tool prints to the
73 console during its execution. When using this option the file and
74 line number are printed.
75 • -Q, --quiet: Silence normal tool output to stdout.
77 • -Z, --enable-errata: Enable the application of errata fixups. Useful
79 if an errata fixup needs to be applied to commands sent to the TPM.
80 Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent. in‐
81 formation many users may expect.
82
84 The TCTI or “Transmission Interface” is the communication mechanism
85 with the TPM. TCTIs can be changed for communication with TPMs across
86 different mediums.
87 To control the TCTI, the tools respect:
89 1. The command line option -T or --tcti
91 2. The environment variable: TPM2TOOLS_TCTI.
93 Note: The command line option always overrides the environment vari‐
95 able.
96 The current known TCTIs are:
98 • tabrmd - The resource manager, called tabrmd
100 (https://github.com/tpm2-software/tpm2-abrmd). Note that tabrmd and
101 abrmd as a tcti name are synonymous.
102 • mssim - Typically used for communicating to the TPM software simula‐
104 tor.
105 • device - Used when talking directly to a TPM device file.
107 • none - Do not initalize a connection with the TPM. Some tools allow
109 for off-tpm options and thus support not using a TCTI. Tools that do
110 not support it will error when attempted to be used without a TCTI
111 connection. Does not support ANY options and MUST BE presented as
112 the exact text of “none”.
113 The arguments to either the command line option or the environment
115 variable are in the form:
116 <tcti-name>:<tcti-option-config>
118 Specifying an empty string for either the <tcti-name> or <tcti-op‐
120 tion-config> results in the default being used for that portion respec‐
121 tively.
122 TCTI Defaults
124 When a TCTI is not specified, the default TCTI is searched for using
125 dlopen(3) semantics. The tools will search for tabrmd, device and
126 mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query
127 what TCTI will be chosen as the default by using the -v option to print
128 the version information. The “default-tcti” key-value pair will indi‐
129 cate which of the aforementioned TCTIs is the default.
130 Custom TCTIs
132 Any TCTI that implements the dynamic TCTI interface can be loaded. The
133 tools internally use dlopen(3), and the raw tcti-name value is used for
134 the lookup. Thus, this could be a path to the shared library, or a li‐
135 brary name as understood by dlopen(3) semantics.
136
138 This collection of options are used to configure the various known TCTI
139 modules available:
140 • device: For the device TCTI, the TPM character device file for use by
142 the device TCTI can be specified. The default is /dev/tpm0.
143 Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI=“de‐
145 vice:/dev/tpm0”
146 • mssim: For the mssim TCTI, the domain name or IP address and port
148 number used by the simulator can be specified. The default are
149 127.0.0.1 and 2321.
150 Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TC‐
152 TI=“mssim:host=localhost,port=2321”
153 • abrmd: For the abrmd TCTI, the configuration string format is a se‐
155 ries of simple key value pairs separated by a `,' character. Each
156 key and value string are separated by a `=' character.
157 • TCTI abrmd supports two keys:
159 1. `bus_name' : The name of the tabrmd service on the bus (a
161 string).
162 2. `bus_type' : The type of the dbus instance (a string) limited to
164 `session' and `system'.
165 Specify the tabrmd tcti name and a config string of bus_name=com.ex‐
167 ample.FooBar:
168 \--tcti=tabrmd:bus_name=com.example.FooBar
170 Specify the default (abrmd) tcti and a config string of bus_type=ses‐
172 sion:
173 \--tcti:bus_type=session
175 NOTE: abrmd and tabrmd are synonymous. the various known TCTI mod‐
177 ules.
178
180 Start a policy session and extend it with a specific locality number
181 (like 3). Attempts to perform other operations would fail.
182 Create an policy restricted by locality 3
184 tpm2_startauthsession -S session.dat
185 tpm2_policylocality -S session.dat -L policy.dat three
187 tpm2_flushcontext session.dat
189 Create the object with auth policy
191 tpm2_createprimary -C o -c prim.ctx
192 tpm2_create -C prim.ctx -u sealkey.pub -r sealkey.priv -L policy.dat \
194 -i- <<< "SEALED-SECRET"
195 Try unseal operation
197 tpm2_load -C prim.ctx -u sealkey.pub -r sealkey.priv -n sealkey.name \
198 -c sealkey.ctx
199 tpm2_startauthsession \--policy-session -S session.dat
201 tpm2_policylocality -S session.dat -L policy.dat three
203 # Change to locality 3, Note: this operation varies on different platforms
205 tpm2_unseal -p session:session.dat -c sealkey.ctx
207 tpm2_flushcontext session.dat
209
211 Tools can return any of the following codes:
212 • 0 - Success.
214 • 1 - General non-specific error.
216 • 2 - Options handling error.
218 • 3 - Authentication error.
220 • 4 - TCTI related error.
222 • 5 - Non supported scheme. Applicable to tpm2_testparams.
224
226 It expects a session to be already established via tpm2_startauthses‐
227 sion(1) and requires one of the following:
228 • direct device access
230 • extended session support with tpm2-abrmd.
232 Without it, most resource managers will not save session state between
234 command invocations.
235
237 Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
238
240 See the Mailing List (https://lists.linuxfoundation.org/mailman/listin‐
241 fo/tpm2)
242tpm2-tools tpm2_policylocality(1)