DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claims 1 and 14 have been amended.
The objections and rejections from the prior correspondence that are not restated herein are withdrawn.
Response to Arguments
Applicant’s argument filed on March 9, 2026 have been fully considered but are not persuasive. Applicant argues that the Examiner’s mapping of the claim limitation “obtain a measurement of the firmware” is legally insufficient because the claim requires the programmable read-only memory to obtain a measurement – an operation performed internally by the device at boot time, whereas KIM’s operations performed by the firmware generator are pre-distribution manufacturing activities, not operations performed by a device’s own programmable read-only memory during boot.
Examiner respectfully disagrees. First, claims 1 and 14 do not recite that the programmable read-only memory obtains a measurement but rather that the programmable read-only memory comprises instructions to obtain the measurement. Furthermore, KIM [0060] teaches controller 210 may execute software stored in the storage portion 220 to boot the electronic device 200 and use new (e.g., updated) firmware. For example, when the electronic device 200 is powered on and/or reset, the controller 210 may execute system software to verify the firmware code and the firmware certificate by loading the firmware image stored in the storage portion 220, and when the verification is successful, the controller 210 may execute the new firmware code using the electronic device 200; [0066] also teaches verification of firmware certificate and firmware code may be performed as part of a booting procedure by a ROM code. In other words, the step of verifying the firmware code and the firmware certificate are operations performed internally by the device at boot time and not pre-distribution manufacturing activities.
Applicant also argues that the claimed “measurement of the firmware” is a value derived from the firmware (e.g. a hash) that characterizes its state and that is stored for later interrogation by a host or external attestor, whereas KIM’s verification architecture is entirely different in purpose and function.
Examiner respectfully disagrees. As Applicant stated, “measurement of the firmware” is a value derived from the firmware (e.g. a hash) that characterizes its state, and KIM [0041] teaches generating a firmware certificate using the firmware hash value and a certificate private key, and [0070] teaches calculating a hash value of the firmware code and firmware signature in the firmware image (operation S320), and may compare the firmware hash value stored in the firmware certificate (e.g., the firmware hash value may be stored in the extended field of the firmware certificate) and the calculated hash value of the firmware code and the firmware signature (operation S330), which is analogous to Applicant’s admission that the “measurement of the firmware” is a value derived from the firmware (e.g. a hash) that characterizes its state.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., the measurement of the firmware “is stored for later interrogation by a host or external attestor” and is not a pass/fail binary authentication operation) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant’s remaining arguments with respect to claims 1 and 14 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-20 are rejected under 103 as being unpatentable over KIM (Pub No.: US 20250061202 A1), hereafter KIM, in view of RAO (US 20240202340 A1), hereafter RAO.
Regarding claim 1, KIM teaches:
A system comprising: a memory device accessible by a first device and a host device, wherein the first device is configured for use with the host device (KIM Fig. 8 & [0078] teach electronic device 800 (i.e. first device) may include a controller 810 and a memory device 820, and [0079] teaches controller 810 may control a memory operation of the memory device 820 by providing a signal to the memory device 820 in response to a request from a host system);
processing circuitry coupled to the memory device; and programmable read-only memory coupled to the memory device (KIM Fig. 5 and [0057] teach electronic device 200 may include a controller 210 and a storage portion 220, where storage portion 220 may include fixed memory such as a ROM and a flash memory),
the programmable read-only memory comprising instructions to, on each boot cycle of the system: initialize the first device; validate firmware that is to execute on the first device (KIM [0060] teaches controller 210 may execute software (e.g., system software such as, but not limited to, a bootstrap loader) stored in the storage portion 220 to boot the electronic device 200 (i.e. on each boot cycle of the system) and use new (e.g., updated) firmware. For example, when the electronic device 200 is powered on and/or reset, the controller 210 may execute system software to verify the firmware code and the firmware certificate by loading the firmware image stored in the storage portion 220, and when the verification is successful, the controller 210 may execute the new firmware code using the electronic device 200; [0066] also teaches verification of firmware certificate and firmware code may be performed as part of a booting procedure (i.e. on each boot cycle of the system) by a ROM code);
obtain a measurement of the firmware (KIM [0037] teaches generating a firmware signature using the firmware private key corresponding to the firmware public key, where the firmware public key stored in the running firmware may be used to verify a firmware signature of newly downloaded firmware; [0041] also teaches generating a firmware certificate using the firmware hash value and a certificate private key; see also [0044] & [0048]; alternatively, [0059] teaches verifying the downloaded firmware image by verifying a firmware signature, and when the verification is successful, the downloaded firmware image may be stored in the storage portion 220; see also [0063]);
initiate execution of the firmware (see KIM [0060] above);
and provide the measurement to the host device, wherein the host device does not interact with the firmware executing on the first device to access the measurement and verify the firmware with the measurement (KIM [0081] teaches electronic device (800) described with reference to Fig. 1-7 may be included in the host system, where controller 810 and/or the memory device 820, and as such, may verify the firmware code and/or firmware certificate).
KIM does not appear to explicitly teach store the measurement in the memory device; lock the measurement stored in the memory device prior to executing the firmware.
However, RAO teaches store the measurement in the memory device (RAO [0032] teaches the cryptographic hardware component executes a hashing algorithm to obtain a digest for all or any number of portions of the software images, and stores the one or more digests in hardware registers of the cryptographic hardware component (see [0033], [0059], and Fig. 2) that were secured during the initial boot configuration to be exclusively read by the secure entity, where [0045] teaches cryptographic hardware component 106 is a sub-chip hardware component of a system on a chip (SoC), which may include other components shown in FIG. 1, and therefore, an SoC comprising cryptographic hardware component 106, memory device 108, and secure entity 112 are seen together as the claimed memory device);
lock the measurement stored in the memory device prior to executing the firmware (RAO [0066] teaches the secure entity performs several actions as part of an initial secure boot configuration, where an example action is to configure, at step 306, a cryptographic hardware component to lock a portion of the hardware registers (e.g., the algorithm result registers 208 of FIG. 2) of the cryptographic hardware component as secured registers (e.g., the secured registers 216) for storing one or more digests calculated via execution of a hashing algorithm by the cryptographic hardware component as the image is being loaded from a storage device to the locked memory device portion (i.e. prior to executing the firmware). Locking the secured registers may include configuring a protection unit of the computing device to include an association between the secure entity and the secured registers such that the secured registers may only be read by the secure entity. Another example action is to configure the computing device such that relevant data paths (e.g., transmit and/or receive direct memory access queues, buffers, etc.) between the storage device and the memory device, including through the cryptographic hardware component, are locked such that they may only be used for obtaining the image from storage, storing the image in memory, and being accessed by the secure entity).
Accordingly, it would have been obvious to a person having ordinary skill in the art at the time of the effective filing of the invention, having the teachings of KIM and RAO before them, to include RAO’s trusted access control for secure boot in KIM’s system distributing firmware image. One would have been motivated to make such a combination in order to provide authentication of software images at different stages and offload certain aspects of the secure boot process to various hardware components as taught by RAO ([0002]).
Regarding claim 14, the claim recites similar limitation as corresponding claim 1 and is rejected for similar reasons as claim 1 using similar teachings and rationale.
Regarding claim 2, KIM in view of RAO teaches the elements of claim 1 as outlined above. KIM also teaches wherein to initialize the first device, the programmable read-only memory is configured to perform an integrity check of the first device (KIM [0070] teaches the controller 210 may calculate a hash value of the firmware code and firmware signature in the firmware image (operation S320), and may compare the firmware hash value stored in the firmware certificate (e.g., the firmware hash value may be stored in the extended field of the firmware certificate) and the calculated hash value of the firmware code and the firmware signature (operation S330)).
Regarding claim 3, KIM in view of RAO teaches the elements of claim 1 as outlined above. KIM also teaches wherein to initialize the first device, the programmable read-only memory is configured to check the memory device to ensure that it has been cleared (KIM [0070] teaches the controller 210 may calculate a hash value of the firmware code and firmware signature in the firmware image (operation S320), and may compare the firmware hash value stored in the firmware certificate (e.g., the firmware hash value may be stored in the extended field of the firmware certificate) and the calculated hash value of the firmware code and the firmware signature (operation S330)).
Regarding claim 4, KIM in view of RAO teaches the elements of claim 1 as outlined above. KIM also teaches wherein to validate the firmware, the programmable read-only memory is configured to: fetch a firmware image of the firmware, the firmware image having a firmware signature; and validate the firmware signature (KIM [0070] teaches the controller 210 may calculate a hash value of the firmware code and firmware signature in the firmware image (operation S320), and may compare the firmware hash value stored in the firmware certificate (e.g., the firmware hash value may be stored in the extended field of the firmware certificate) and the calculated hash value of the firmware code and the firmware signature (operation S330)).
Regarding claim 5, KIM in view of RAO teaches the elements of claim 4 as outlined above. KIM also teaches wherein the firmware image is a bootloader firmware image (KIM [0060] teaches the controller 210 may execute software (e.g., system software such as, but not limited to, a bootstrap loader) stored in the storage portion 220 to boot the electronic device 200).
Regarding claim 6, KIM in view of RAO teaches the elements of claim 4 as outlined above. KIM also teaches wherein the firmware image is a device firmware image (KIM [0066] teaches executing the electronic device 200 using the firmware image of which verification has been successful).
Regarding claim 7, KIM in view of RAO teaches the elements of claim 4 as outlined above. KIM also teaches wherein to validate the firmware signature, the programmable read-only memory is configured to: execute a hash algorithm using at least a portion of the firmware image as input to the hash algorithm, the hash algorithm producing a hash; and compare the hash to the firmware signature (KIM [0070] teaches the controller 210 may calculate a hash value of the firmware code and firmware signature in the firmware image (operation S320), and may compare the firmware hash value stored in the firmware certificate (e.g., the firmware hash value may be stored in the extended field of the firmware certificate) and the calculated hash value of the firmware code and the firmware signature (operation S330)).
Regarding claim 8, KIM in view of RAO teaches the elements of claim 7 as outlined above. KIM also teaches:
wherein to compare the hash to the firmware signature, the programmable read-only memory is configured to: obtain a public key associated with a provider of the firmware image (KIM [0037] teaches the firmware public key stored in the running firmware may be used to verify a firmware signature of newly downloaded firmware);
decrypt the firmware signature with the public key to produce a decrypted hash; and compare the hash to the decrypted hash (KIM [0063] teaches performing verification on the firmware signature in the firmware image using the firmware public key, where the controller 210 may use one or more algorithms to decrypt the firmware signature, such as, but not limited to, an elliptic curve cryptography (ECC) algorithm, a secure hash algorithm (SHA), and the like; [0068] also teaches decoding the firmware certificate signature of the firmware certificate in the firmware image using a certificate public key to verify the firmware certificate, where the controller 210 may use the ECC algorithm and/or SHA, and the like to decrypt the firmware signature).
Regarding claim 9, KIM in view of RAO teaches the elements of claim 1 as outlined above. KIM also teaches wherein to obtain the measurement of the firmware, the programmable read-only memory is configured to execute a hash algorithm on a portion of a firmware image of the firmware, to produce an unencrypted measurement (KIM [0036] teaches generating a hash value for the firmware code and encrypting the hash value of the firmware code (i.e. unencrypted prior to encrypting) using a firmware private key for firmware signature, thereby generating the firmware signature; [0044] also teaches calculating the hash value of the firmware certificate and encrypting the calculated hash value using the certificate private key to generate a certificate signature of the certificate; see also [0048]).
Regarding claim 10, KIM in view of RAO teaches the elements of claim 9 as outlined above. KIM also teaches wherein to obtain the measurement of the firmware, the programmable read-only memory is configured to encrypt the unencrypted measurement to produce an encrypted measurement (see KIM [0036], [0044], and [0048] as taught above in claim 9; see also [0050] & [0063]).
Regarding claim 11, KIM in view of RAO teaches the elements of claim 1 as outlined above. RAO also teaches:
wherein to store the measurement in the memory device, the programmable read-only memory is configured to write the measurement to a platform configuration register (see RAO [0032-0033], [0059], [0066], and Fig. 2 as taught above in claim 1).
The same motivation that was utilized for combining KIM and RAO as set forth in claim 1 is equally applicable to claim 11.
Regarding claim 12, KIM in view of RAO teaches the elements of claim 11 as outlined above. RAO also teaches:
wherein the memory device is a hardware register (see RAO [0032-0033], [0059], [0066], and Fig. 2 as taught above in claim 1).
The same motivation that was utilized for combining KIM and RAO as set forth in claim 1 is equally applicable to claim 12.
Regarding claim 13, KIM in view of RAO teaches the elements of claim 1 as outlined above. KIM also teaches wherein to initiate execution of the firmware, the programmable read-only memory is configured to initiate execution of a bootloader firmware image (KIM [0060] teaches the controller 210 may execute software (e.g., system software such as, but not limited to, a bootstrap loader) stored in the storage portion 220 to boot the electronic device 200).
Regarding claim 15, the claim recites similar limitation as corresponding claim 2 and is rejected for similar reasons as claim 2 using similar teachings and rationale.
Regarding claim 16, the claim recites similar limitation as corresponding claim 3 and is rejected for similar reasons as claim 3 using similar teachings and rationale.
Regarding claim 17, the claim recites similar limitation as corresponding claim 4 and is rejected for similar reasons as claim 4 using similar teachings and rationale.
Regarding claim 18, the claim recites similar limitation as corresponding claim 5 and is rejected for similar reasons as claim 5 using similar teachings and rationale.
Regarding claim 19, the claim recites similar limitation as corresponding claim 6 and is rejected for similar reasons as claim 6 using similar teachings and rationale.
Regarding claim 20, the claim recites similar limitation as corresponding claim 7 and is rejected for similar reasons as claim 7 using similar teachings and rationale.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
CHENG (Pub. No.: US 20230214491 A1) – “FIRMWARE VERIFICATION SYSTEM AND FIRMWARE VERIFICATION METHOD” relates to calculating hash value of the first public key is the same as the first initial public key hash value in the first entry, the bootloader calculates a hash value of a first firmware according to the first length of the firmware and the first storage address of the firmware included in the first entry, then uses the first public key to decrypt a first digital signature of the first firmware to obtain a decryption result, and compares a hash value of the first firmware with the decryption result; when the hash value of the first firmware is the same as the decryption result, it is determined that the first digital signature is correct; when the hash value of the first firmware is different from the decryption result, it is determined that the content of the first firmware is wrong, and the bootloader stores firmware error information in the first firmware information and directly reads the second entry.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW J JUNG whose telephone number is 571-270-3779. The examiner can normally be reached on Monday through Friday from 9am to 5pm.
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/ANDREW J JUNG/Supervisory Patent Examiner, Art Unit 2175
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