Provided by: tpm2-tools_5.6-1build4_amd64 
NAME
tpm2_policyor(1) - logically OR’s two policies together.
SYNOPSIS
tpm2_policyor [OPTIONS]
DESCRIPTION
tpm2_policyor(1) - Generates a policy_or event with the TPM. It expects a session to be already estab‐
lished via tpm2_startauthsession(1). If the input session is a trial session this tool generates a poli‐
cy digest that compounds two or more input policy digests such that the resulting policy digest requires
at least one of the policy events being true. If the input session is real policy session tpm2_policy‐
or(1) authenticates the object successfully if at least one of the policy events are true.
OPTIONS
• -L, --policy=FILE:
File to save the compounded policy digest.
• -S, --session=FILE:
The policy session file generated via the -S option to tpm2_startauthsession(1).
• ARGUMENT the command line argument specifies the list of files for the policy digests that has to be
compounded resulting in individual policies being added to final policy digest that can authenticate
the object. The list begins with the policy digest hash alg. Example sha256:policy1,policy2
• -l, --policy-list=POLICY_FILE_LIST:
This option is DEPRECATED yet is retained for backwards compatibility. Use the argument method in‐
stead. NOTE: When -l and an argument is specified it’s the same as specifying it all at once. For in‐
stance: tpm2_policyor -l sha256:file1 sha256:file2 is the same as tpm2_policyor sha256:file1,file2.
References
COMMON OPTIONS
This collection of options are common to many programs and provide information that many users may ex‐
pect.
• -h, --help=[man|no-man]: Display the tools manpage. By default, it attempts to invoke the manpager for
the tool, however, on failure will output a short tool summary. This is the same behavior if the “man”
option argument is specified, however if explicit “man” is requested, the tool will provide errors from
man on stderr. If the “no-man” option if specified, or the manpager fails, the short options will be
output to stdout.
To successfully use the manpages feature requires the manpages to be installed or on MANPATH, See
man(1) for more details.
• -v, --version: Display version information for this tool, supported tctis and exit.
• -V, --verbose: Increase the information that the tool prints to the console during its execution. When
using this option the file and line number are printed.
• -Q, --quiet: Silence normal tool output to stdout.
• -Z, --enable-errata: Enable the application of errata fixups. Useful if an errata fixup needs to be
applied to commands sent to the TPM. Defining the environment TPM2TOOLS_ENABLE_ERRATA is equivalent.
information many users may expect.
TCTI Configuration
The TCTI or “Transmission Interface” is the communication mechanism with the TPM. TCTIs can be changed
for communication with TPMs across different mediums.
To control the TCTI, the tools respect:
1. The command line option -T or --tcti
2. The environment variable: TPM2TOOLS_TCTI.
Note: The command line option always overrides the environment variable.
The current known TCTIs are:
• tabrmd - The resource manager, called tabrmd (https://github.com/tpm2-software/tpm2-abrmd). Note that
tabrmd and abrmd as a tcti name are synonymous.
• mssim - Typically used for communicating to the TPM software simulator.
• device - Used when talking directly to a TPM device file.
• none - Do not initalize a connection with the TPM. Some tools allow for off-tpm options and thus sup‐
port not using a TCTI. Tools that do not support it will error when attempted to be used without a TC‐
TI connection. Does not support ANY options and MUST BE presented as the exact text of “none”.
The arguments to either the command line option or the environment variable are in the form:
<tcti-name>:<tcti-option-config>
Specifying an empty string for either the <tcti-name> or <tcti-option-config> results in the default be‐
ing used for that portion respectively.
TCTI Defaults
When a TCTI is not specified, the default TCTI is searched for using dlopen(3) semantics. The tools will
search for tabrmd, device and mssim TCTIs IN THAT ORDER and USE THE FIRST ONE FOUND. You can query what
TCTI will be chosen as the default by using the -v option to print the version information. The “de‐
fault-tcti” key-value pair will indicate which of the aforementioned TCTIs is the default.
Custom TCTIs
Any TCTI that implements the dynamic TCTI interface can be loaded. The tools internally use dlopen(3),
and the raw tcti-name value is used for the lookup. Thus, this could be a path to the shared library, or
a library name as understood by dlopen(3) semantics.
TCTI OPTIONS
This collection of options are used to configure the various known TCTI modules available:
• device: For the device TCTI, the TPM character device file for use by the device TCTI can be specified.
The default is /dev/tpm0.
Example: -T device:/dev/tpm0 or export TPM2TOOLS_TCTI=“device:/dev/tpm0”
• mssim: For the mssim TCTI, the domain name or IP address and port number used by the simulator can be
specified. The default are 127.0.0.1 and 2321.
Example: -T mssim:host=localhost,port=2321 or export TPM2TOOLS_TCTI=“mssim:host=localhost,port=2321”
• abrmd: For the abrmd TCTI, the configuration string format is a series of simple key value pairs sepa‐
rated by a `,' character. Each key and value string are separated by a `=' character.
• TCTI abrmd supports two keys:
1. `bus_name' : The name of the tabrmd service on the bus (a string).
2. `bus_type' : The type of the dbus instance (a string) limited to `session' and `system'.
Specify the tabrmd tcti name and a config string of bus_name=com.example.FooBar:
\--tcti=tabrmd:bus_name=com.example.FooBar
Specify the default (abrmd) tcti and a config string of bus_type=session:
\--tcti:bus_type=session
NOTE: abrmd and tabrmd are synonymous. the various known TCTI modules.
EXAMPLES
Create an authorization policy for a sealing object that compounds a pcr policy and a policypassword in
an OR fashion and show satisfying either policies could unseal the secret.
Create policypcr as first truth value for compounding the policies
tpm2_startauthsession -S session.ctx
tpm2_policypcr -S session.ctx -L policy.pcr -l sha256:0,1,2,3
tpm2_flushcontext session.ctx
Create policypassword as second truth value for compounding the policies
tpm2_startauthsession -S session.ctx
tpm2_policypassword -S session.ctx -L policy.pass
tpm2_flushcontext session.ctx
Compound the two policies in an OR fashion with tpm2_policyor command
tpm2_startauthsession -S session.ctx
tpm2_policyor -S session.ctx -L policy.or sha256:policy.pass,policy.pcr
tpm2_flushcontext session.ctx
Create a sealing object and attach the auth policy from tpm2_policyor command
tpm2_createprimary -c prim.ctx -Q
echo "secret" | tpm2_create -C prim.ctx -c key.ctx -u key.pub -r key.priv \
-L policy.or -i-
Satisfy auth policy using password and unseal the secret
tpm2_startauthsession -S session.ctx --policy-session
tpm2_policypassword -S session.ctx
tpm2_policyor -S session.ctx sha256:policy.pass,policy.pcr
tpm2_unseal -c key.ctx -p session:session.ctx
tpm2_flushcontext session.ctx
Satisfy auth policy using pcr and unseal the secret
tpm2_startauthsession -S session.ctx --policy-session
tpm2_policypcr -S session.ctx -l sha256:0,1,2,3
tpm2_policyor -S session.ctx sha256:policy.pass,policy.pcr
tpm2_unseal -c key.ctx -p session:session.ctx
tpm2_flushcontext session.ctx
Returns
Tools can return any of the following codes:
• 0 - Success.
• 1 - General non-specific error.
• 2 - Options handling error.
• 3 - Authentication error.
• 4 - TCTI related error.
• 5 - Non supported scheme. Applicable to tpm2_testparams.
Limitations
It expects a session to be already established via tpm2_startauthsession(1) and requires one of the fol‐
lowing:
• direct device access
• extended session support with tpm2-abrmd.
Without it, most resource managers will not save session state between command invocations.
BUGS
Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)
HELP
See the Mailing List (https://lists.linuxfoundation.org/mailman/listinfo/tpm2)
tpm2-tools tpm2_policyor(1)