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    <p>I assume you mean a TPM version 1.2 on a PC platform, so the following specification documents are of interest for you:</p> <ul> <li><a href="http://www.trustedcomputinggroup.org/resources/tpm_main_specification">TPM Main Part 2 TPM Structures</a></li> <li><a href="http://www.trustedcomputinggroup.org/resources/pc_client_work_group_pc_client_specific_tpm_interface_specification_tis">TCG PC Client Specific TPM Interface Specification (TIS)</a></li> </ul> <p>Now to your questions:</p> <ol> <li><p>"How to extend the running application into PCR?"</p> <p>You need some piece of software that identifies "<em>the running application</em>" (=<em>measure</em>) and issue a <code>TPM_Extend</code> command to the TPM. Usually this is done through a TSS, but you can also do that with a self written program, the <code>TPM_Extend</code> command is not that complex.</p> <p><em>Identifying</em> means calculating a SHA-1 hash in most cases, but the TPM does not care. The description of the data you provide is:</p> <pre><code>The 160 bit value representing the event to be recorded. </code></pre></li> <li><p>"Which PCR can be used for it?"</p> <p>This depends on your actual environment. Access to PCRs are controlled by <em>localities</em>. Here is a table showing which PCR can be extended in which locality:</p> <pre><code>PCR Alias (description) Extendable in localities ----------------------------------------------------------------- 0-15 Static RTM 4,3,2,1,0 16 Debug 4,3,2,1,0 17 Locality 4 4,3,2 18 Locality 3 4,3,2 19 Locality 2 3,2 20 Locality 1 3,2,1 21 Dynamic OS controlled 2 22 Dynamic OS controlled 2 23 Application Specific 4,3,2,1,0 </code></pre> <p>Which locality you are in depends on your environment. If you are in a Linux userspace, for exmaple, you have locality 0.</p> <p>If you are designing a trusted architecture you will also have to consider how the PCRs can be reset (in which localities).</p> <p>The localities are described in <em><a href="http://www.trustedcomputinggroup.org/resources/pc_client_work_group_pc_client_specific_tpm_interface_specification_tis">TCG PC Client Specific TPM Interface Specification (TIS)</a></em>:</p> <ul> <li><p>Locality 4: Trusted hardware component. This is used by the D-CRTM to establish the Dynamic RTM.</p></li> <li><p>Locality 3: Auxiliary components. Use of this is optional and, if used, it is implementation dependent.</p></li> <li><p>Locality 2: Dynamically Launched OS (Dynamic OS) “runtime” environment.</p></li> <li><p>Locality 1: An environment for use by the Dynamic OS.</p></li> <li><p>Locality 0: The Static RTM, its chain of trust and its environment.</p></li> </ul></li> </ol>
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    1. POHow to extend the running application into PCR?
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    1. COI am unclear on this SHA-1 hash calculation: Calculating SHA-1 of all the files of the Application or Just Binary?
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    2. COThis depends on your desired system architecture. For a trusted system you would have to measure everything that can affect system behavior.
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    3. COcan you shed some light on localities, what they are? by some example!
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