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tpm_clear(8)		     System Manager's Manual		    tpm_clear(8)

			   TPM Management - tpm_clear

NAME
     tpm_clear	-  return the TPM to the default state (unowned, disabled, inac-
     tive)

SYNOPSIS
     tpm_clear [OPTION]

DESCRIPTION
     tpm_clear requests that the system's TPM perform a clear (via the	TPM_Own-
     erClear  API)  wiping  out all ownership information, in effect invalidaing
     all keys and data tied to the TPM, as well as  disabling  and  deactivating
     the  TPM.	 This operation will prompt for the owner password.  The --force
     option relies on Phyiscal	Presence  to  authorize  the  command  (via  the
     TPM_ForceClear API) skipping the owner password prompt.  The TPM OwnerClear
     API  can  be  disabled until the current owner is cleared, requiring use of
     the --force with tpm_setclearable command.   The TPM_ForceClear API can  be
     disabled  for  the  current  boot	cycle with the tpm_setclearable command.
     This command requires a reboot to complete the operation.

     -h, --help
	    Display command usage info.

     -v, --version
	    Display command version info.

     -l, --log [none|error|info|debug]
	    Set logging level.

     -u, --unicode
	    Use TSS UNICODE encoding for passwords to comply  with  applications
	    using TSS popup boxes

     -f, --force
	    Rely  on  Physical	Presence  for  authorization;  therefore, do not
	    prompt for owner password.

     -z, --well-known
	    Authenticate using 20 bytes of zeros as owner password (the  default
	    TSS Well Known Secret), instead of prompting for an owner password.

SEE ALSO
     tpm_version(1),   tpm_takeownership(8),   tpm_setclearable(8),   tpm_setac-
     tive(8), tpm_setenable(8), tcsd(8)

REPORTING BUGS
     Report bugs to <trousers-users@lists.sourceforge.net>

TPM Management			   2005-05-05			    tpm_clear(8)

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