Provided by: tpm2-tools_5.4-1_amd64 bug

NAME

       tpm2_getcommandauditdigest(1) - Retrieve the command audit attestation data from the TPM.

SYNOPSIS

       tpm2_getcommandauditdigest [OPTIONS]

DESCRIPTION

       tpm2_getcommandauditdigest(1)  - Retrieve the command audit attestation data from the TPM.
       The attestation data includes the audit digest of the commands in the setlist setup  using
       the  command tpm2_setcommandauditstatus.  Also the attestation data includes the digest of
       the list of commands setup  for  audit.   The  audit  digest  algorith  is  setup  in  the
       tpm2_setcommandauditstatus.

OPTIONS

-P, --hierarchy-auth=AUTH:

         Specifies the authorization value for the endorsement hierarchy.

       • -c, --key-context=OBJECT:

         Context object for the signing key that signs the attestation data.

       • -p, --auth=AUTH:

         Specifies the authorization value for key specified by option -c.

       • -q, --qualification=HEX_STRING_OR_PATH:

         Data  given  as  a  Hex  string  or binary file to qualify the quote, optional.  This is
         typically used to add a nonce against replay attacks.

       • -s, --signature=FILE:

         Signature output file, records the signature in the format specified via the -f option.

       • -m, --message=FILE:

         Message output file, records the quote message that makes up the data that is signed  by
         the TPM.  This is the command audit digest attestation data.

       • -f, --format=FORMAT:

         Format selection for the signature output file.

       • -g, --hash-algorithm:

         Hash algorithm for signature.  Defaults to sha256.

       • --scheme=ALGORITHM:

         The  signing  scheme used to sign the message.  Optional.  Signing schemes should follow
         the “formatting standards”, see  section  “Algorithm  Specifiers”.   Also,  see  section
         “Supported  Signing  Schemes”  for a list of supported signature schemes.  If specified,
         the signature scheme must match the key type.  If left unspecified, a default  signature
         scheme for the key type will be used.

   References

Context Object Format

       The type of a context object, whether it is a handle or file name, is determined according
       to the following logic in-order:

       • If the argument is a file path, then the file is loaded  as  a  restored  TPM  transient
         object.

       • If the argument is a prefix match on one of:

         • owner: the owner hierarchy

         • platform: the platform hierarchy

         • endorsement: the endorsement hierarchy

         • lockout: the lockout control persistent object

       • If  the  argument  argument  can  be  loaded  as  a number it will be treat as a handle,
         e.g. 0x81010013 and used directly._OBJECT_.

Authorization Formatting

       Authorization for use of an object in TPM2.0 can come in 3 different forms:  1.   Password
       2.  HMAC 3.  Sessions

       NOTE: “Authorizations default to the EMPTY PASSWORD when not specified”.

   Passwords
       Passwords are interpreted in the following forms below using prefix identifiers.

       Note:  By  default  passwords are assumed to be in the string form when they do not have a
       prefix.

   String
       A string password, specified by prefix “str:” or it’s absence (raw string without  prefix)
       is not interpreted, and is directly used for authorization.

   Examples
              foobar
              str:foobar

   Hex-string
       A  hex-string  password,  specified  by prefix “hex:” is converted from a hexidecimal form
       into a byte array form, thus allowing passwords with  non-printable  and/or  terminal  un-
       friendly characters.

   Example
              hex:1122334455667788

   File
       A file based password, specified be prefix “file:” should be the path of a file containing
       the password to be read by the tool or a “-” to use stdin.   Storing  passwords  in  files
       prevents  information  leakage,  passwords  passed as options can be read from the process
       list or common shell history features.

   Examples
              # to use stdin and be prompted
              file:-

              # to use a file from a path
              file:path/to/password/file

              # to echo a password via stdin:
              echo foobar | tpm2_tool -p file:-

              # to use a bash here-string via stdin:

              tpm2_tool -p file:- <<< foobar

   Sessions
       When using a policy session to authorize the use of an object, prefix the option  argument
       with  the  session  keyword.  Then indicate a path to a session file that was created with
       tpm2_startauthsession(1).  Optionally, if the session requires an auth value  to  be  sent
       with the session handle (eg policy password), then append a + and a string as described in
       the Passwords section.

   Examples
       To use a session context file called session.ctx.

              session:session.ctx

       To use a session context file called session.ctx AND send the authvalue mypassword.

              session:session.ctx+mypassword

       To use a session context file called session.ctx AND send the HEX authvalue 0x11223344.

              session:session.ctx+hex:11223344

   PCR Authorizations
       You can satisfy a PCR policy using the “pcr:” prefix and the PCR  minilanguage.   The  PCR
       minilanguage is as follows: <pcr-spec>=<raw-pcr-file>

       The PCR spec is documented in in the section “PCR bank specifiers”.

       The  raw-pcr-file is an optional argument that contains the output of the raw PCR contents
       as returned by tpm2_pcrread(1).

       PCR bank specifiers

   Examples
       To satisfy a PCR policy of sha256 on banks 0, 1, 2 and 3 use a specifier of:

              pcr:sha256:0,1,2,3

       specifying AUTH.

Signature Format Specifiers

       Format selection for the signature output file.  tss (the default) will  output  a  binary
       blob  according  to  the  TPM  2.0  specification and any potential compiler padding.  The
       option plain will output the plain signature data as defined  by  the  used  cryptographic
       algorithm.  signature FORMAT.

COMMON OPTIONS

       This  collection  of options are common to many programs and provide information that many
       users may expect.

       • -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 support not using a TCTI.  Tools  that  do  not  support  it  will  error  when
         attempted  to  be used without a TCTI 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 being 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 “default-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 separated 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

              tpm2_getcommandauditdigest -P ekpass -c key.ctx -p keypass -m att.data -s att.sig

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.

BUGS

       Github Issues (https://github.com/tpm2-software/tpm2-tools/issues)

HELP

       See the Mailing List (https://lists.linuxfoundation.org/mailman/listinfo/tpm2)