Ex Parte Butler et al

Patent Trial and Appeal Board

Aug 30, 2017

12851046 (P.T.A.B. Aug. 30, 2017)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/851,046 08/05/2010 Kevin R. Butler PST-47302/36 1997
25006 7590 09/01/2017
DTNSMORF fr SHOHT T T P
EXAMINER
900 Wilshire Drive TRAORE, FATOUMATA
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TROY, MI 48084 ART UNIT PAPER NUMBER
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NOTIFICATION DATE DELIVERY MODE
09/01/2017 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
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PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KEVIN R. BUTLER, STEPHEN E. McLAUGHLIN, and
PATRICK D. McDANIEL
Appeal 2016-001280
Application 12/851,0461
Technology Center 2400
Before JUSTIN BUSCH, JAMES W. DEJMEK, and
JOYCE CRAIG, Administrative Patent Judges.
DEJMEK, Administrative Patent Judge.
DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134(a) from a Non-Final
Rejection of claims 1—12. Oral arguments were heard on August 17, 2017.
A transcript of the hearing will be placed in the record in due course. We
have jurisdiction over the pending claims under 35 U.S.C. § 6(b). Ex parte
Lemoine, 46 USPQ2d 1420, 1423 (BPAI 1994) (precedential).
We affirm.
1 Appellants identify The Penn State Research Foundation as the real party
in interest. App. Br. 1.
Appeal 2016-001280
Application 12/851,046
STATEMENT OF THE CASE
Introduction
Appellants’ disclosed and claimed invention is directed to rootkit-
resistant disks (RRDs) that prevent rootkit persistence. Spec. 12.
According to the Specification, rootkits are used to exploit vulnerabilities in
operating systems and allow the perpetrator of the rootkit to gain control of a
victim host. Spec. 13. Rootkits compromise a host system by replacing or
modifying system images, call tables, binaries, or configurations with
malicious code. Spec. H 3^4. In a disclosed embodiment, write access to
the system image is tightly controlled and enforced at the disk processor,
rather than in the operating system. Spec. 19. In Appellants’disclosed
invention, control over the system image may be achieved by using an
administrative token during the installation (or upgrade) of the system
image. Spec. 110. The token labels blocks of memory associated with the
system image as being immutable during installation. Spec. 110.
According to the Specification, when the token is not present, attempts to
write to blocks labeled as immutable are blocked. Spec. 110.
Claim 1 is representative of the subject matter on appeal and is
reproduced below with the disputed limitations emphasized in italics'.
1. In a computer system wherein a host processor communicates
with a storage device operated by a storage-device controller, a method
of protecting the storage device against rootkit exploitation, comprising
the steps of:
installing a physical token in the storage device during the
installation of an operating system on the host processor or during a
system upgrade, such that regions of the storage device are labeled as
immutable by the token',
wherein the token is installed directly into the storage device,
bypassing the host processor, and
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Application 12/851,046
whereby, following the installation or upgrade, any attempted
modification of an immutable region during normal operation of the
host processor is blocked by the storage device controller.
The Examiner’s Rejections
1. Claims 1, 2, and 4—12 stand rejected under 35 U.S.C. § 103(a)
as being unpatentable over Thibadeau (US 2005/0262361 Al; Nov. 24,
2005) and Bress et al. (US 6,813,682 B2; Nov. 2, 2004) (“Bress”). Non-
Final Act. 3—7.
2. Claim 3 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Thibadeau, Bress, and Parkinson et al. (US 2008/0056496
Al; Mar. 6, 2008) (“Parkinson”). Non-Final Act. 7—8.
ANALYSIS2
Claims 1, 2, and 4^12
Appellants contend Thibadeau fails to teach or suggest the limitation
“such that regions of the storage device are labeled as immutable by the
token,” as recited in claim 1. App. Br. 2—3; Reply Br. 1—2. Instead,
Appellants assert Thibadeau discloses the use of a physical token in order to
access encrypted data stored on the hard drive. App. Br. 2—3 (citing
Thibadeau Tflf 66—67, Fig. 5). Appellants argue the token of Thibadeau
merely allows or denies access to the data on the storage device, but does not
2 Throughout this Decision we have considered the Appeal Brief, filed
March 23, 2015 (“App. Br.”); the Reply Brief, filed October 21, 2015
(“Reply Br.”); the Examiner’s Answer, mailed on August 21, 2015 (“Ans.”);
the Non-Final Office Action, mailed August 28, 2014 (“Non-Final Act.”),
from which this Appeal is taken; and Appellant’s arguments made during the
Oral Hearing held August 17, 2017.
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Application 12/851,046
perform any specific functions (i.e., labeling regions as immutable) on the
storage device. App. Br. 3; Reply Br. 2. In other words, Appellants contend
the token of Thibadeau functions as an ON/OFF switch to gain or deny
access to the storage device. App. Br. 3.
When construing claim terminology during prosecution before the
Office, claims are to be given their broadest reasonable interpretation
consistent with the Specification, reading claim language in light of the
Specification as it would be interpreted by one of ordinary skill in the art.
In re Am. Acad. ofSci. Tech. Ctr., 367 F.3d 1359, 1364 (Fed. Cir. 2004).
We are mindful, however, that limitations are not to be read into the claims
from the Specification. In re Van Geuns, 988 F.2d 1181, 1184 (Fed.
Cir. 1993). Because “applicants may amend claims to narrow their scope, a
broad construction during prosecution creates no unfairness to the applicant
or patentee.” In re ICON Health and Fitness, Inc., 496 F.3d 1374, 1379
(Fed. Cir. 2007) (citation omitted). Additionally, absent an express intent to
impart a novel meaning to a claim term, the words take on the ordinary and
customary meanings attributed to them by those of ordinary skill in the
art. Brookhill-Wilk 1, LLC v. Intuitive Surgical, Inc., 334 F.3d 1294, 1298
(Fed. Cir. 2003) (citation omitted).
Here, Appellants have not clearly expressed an intent to assign a
unique definition to labeling regions of the storage device as immutable by
the token. See Helmsderfer v. Bobrick Washroom Equip., Inc., 527 F.3d
1379, 1381 (Fed. Cir. 2008). According to the Specification, a label
indicates whether the corresponding block of memory is immutable. Spec.
110, see also Spec. 128 (describing data blocks that are written when a
token is present are immutable), Spec. 142 (describing a storage disk as a
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Application 12/851,046
set of contiguous ranges and assigning a label to range). Thus, consistent
with the Specification, we construe “regions of the storage device are
labeled as immutable by the token” as the token is used to identify regions of
the storage device as immutable.
Thibadeau generally relates to the “safe disposal of magnetic storage
media,” particularly when such media contain information that is both
confidential and recoverable. Thibadeau Tflf 1—2. Specifically, the disclosed
invention of Thibadeau relates to a controller to control data transfers
between a host system and the storage media. Thibadeau 121. In particular,
the controller is adapted to encrypt and decrypt data written to or read from
the storage media using an encryption key. Thibadeau 121. In a disclosed
embodiment, the encryption key may be based on a removable token.
Thibadeau H 25, 65—67, Fig. 5. Thibadeau discloses the removable token
may be a USB dongle that integrates with a port of the storage device during
execution in order to verify its presence. Thibadeau 1 66. Thus, the token
(i.e., USB dongle) serves as a hardware key to unlock the drive. Thibadeau
1 66. If the token is not present, access to the encrypted data stored on the
storage device (i.e., storage media) is prevented. Thibadeau 1 67.
Thibadeau further discloses the storage device may be partitioned and a
particular partition may be encrypted in accordance with the encryption key
of the removable token. Thibadeau H 74—75.
Bress also relates to controlling user access to storage devices. Bress,
col. 1,11. 13—15. In particular, Bress discloses using a blocking device
inserted between a host computer and a storage device. Bress, col. 3,11. 50—
55, see also Bress, col. 5,11. 24—31, Figs. 2, 3. The blocking device only
allows commands that are safe (i.e., will not modify the drive) to pass.
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Bress, col. 6,11. 30-33. Additionally, Bress discloses an embodiment
wherein selective write commands are blocked. Bress, col. 10,1. 32—col. 11,
I. 23. Under the selective blocking embodiment, Bress discloses a user may
specify areas of a storage device (e.g., a range of sectors) for which to block
write access. Bress, col. 10,1. 65—col. 11,1. 5, see also Bress, col. 11,11. 16—
20 (describing a list of areas of the drive that require authorization to
access). Bress further discloses by selectively blocking portions of the
storage device (e.g., portions containing the operating system), the user may
be protected from an attack by a malicious user or software. Bress, col. 11,
II. 6-14.
In rejecting claim 1, the Examiner finds, inter alia, Thibadeau
discloses a physical token is used to label regions of the storage device as
immutable. Non-Final Act. 3 (citing Thibadeau H 65—67). Additionally,
the Examiner responds that the combination of Thibadeau and Bress also
teaches or suggests the disputed limitation. Ans. 4—5 (citing Thibadeau
11 65-67, Bress, col. 3,11. 50-67, col. 6,11. 16-33).
We are unpersuaded of Examiner error because, as described supra,
Thibadeau discloses using a token having an encryption key to encrypt data
being written. See Thibadeau H 65—67. Additionally, Thibadeau describes
preventing write access to the storage device (or partitions thereof) if the
token having the encryption key is not present. See Thibadeau H 67, 74—75.
Thus, by preventing write access when a token is not present to those
regions of the storage device that have been encrypted when the token was
present, we agree with the Examiner that Thibadeau teaches, or reasonably
suggests, the token identifying (i.e., labeling) regions of the storage device
as immutable (i.e., not allowing write access). Further, Bress also describes
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blocking write access by a blocking device to particular regions of a storage
device (e.g., regions containing the operating system files). Bress, col. 10,1.
32—col. 11,1. 23.
Regarding the limitation of claim 1 “whereby . . . any attempted
modification of an immutable region during normal operation of the host
processor is blocked by the storage device controller,” Appellants contend
Bress does not recite an “immutable region” or “normal operation.” App.
Br. 3. Instead, Appellants argue Bress does not use a token to determine
whether writes are blocked and that Bress teaches the use of a user interface
that allows for custom programming of the memory. App. Br. 4 (citing
Bress Selective Blocking Device (i.e., col. 10,1. 32—col. 11,1. 23), Fig. 9).
Obviousness is not an ipsissimis verbis test. Rather, a prima facie
case of obviousness is established when the prior art, itself, would appear to
have suggested the claimed subject matter to a person of ordinary skill in the
art. In re Rinehart, 531 F.2d 1048, 1051 (CCPA 1976). As discussed supra,
Bress describes a range of sectors for which write access is blocked by the
blocking device. See Bress, col. 10,1. 65—col. 11,1. 5, see also Bress,
col. 11,11. 16—20. Thus, we find Appellants’ argument unpersuasive and
agree with the Examiner that Bress teaches an immutable region (i.e., Bress’
range of sectors) for which write access is blocked.
Appellants also contend Thibadeau fails to teach “the token is
installed directly into the storage device, bypassing the host processor.”
App. Br. 3. Appellants assert the token of Thibadeau controls data between
the host and storage device and, therefore, does not bypass the host. App.
Br. 3.
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As illustrated in Figure 5 of Thibadeau, the removable token is
inserted into the controller of the storage system. See Thibadeau 121,
Fig. 5. The token (and its information) does not pass through the host
processor and, accordingly, bypasses the host processor. See Thibadeau
65—67. Accordingly, we find Appellants’ argument unpersuasive of
Examiner error.
Appellants assert the Examiner’s reason to combine the teachings of
Thibadeau and Bress—i.e., to enhance the security of the storage device—
lacks support. App. Br. 4; Reply Br. 2. Appellants argue “Thibadeau
already provides the ultimate in security insofar as if the token is lost or
destroyed, the storage medium cannot be accessed at all.” App. Br. 4.
Appellants contend such a system would be difficult to enhance. App. Br. 4.
The U.S. Supreme Court has held the relevant inquiry in an
obviousness analysis is whether the Examiner has set forth “some articulated
reasoning with some rational underpinning to support the legal conclusion of
obviousness.” In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006) (cited with
approval in KSR Int 7 Co. v. Teleflex, Inc., 550 U.S. 398, 418 (2007)).
Contrary to Appellants’ assertions, we agree with the Examiner that
an ordinarily-skilled artisan would have been motivated to combine the
teachings of Thibadeau and Bress in order to enhance the security of the
storage system. For instance, rather than rendering the entire storage system
inaccessible in the event the token is lost or destroyed, as suggested by
Appellants, the requirement of a token to access the storage device as in
Thibadeau could be limited to the range of sectors as in Bress—thereby
avoiding having the entire storage device be inaccessible if the token were
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Application 12/851,046
lost or destroyed (i.e., enhancing the security of the storage device). Thus,
we are unpersuaded of Examiner error.
For the reasons discussed supra, we are unpersuaded of Examiner
error. Accordingly, we sustain the Examiner’s rejection of independent
claim 1. For similar reasons, we also sustain the Examiner’s rejection of
independent claim 8, which recites similar limitations and was not argued
separately. See App. Br. 2—\. Additionally, we sustain the Examiner’s
rejection of claims 2, 4—7, and 9—12, which depend therefrom and were not
argued separately. See App. Br. 2-4.
Claim 3
In contesting the Examiner’s rejection of claim 3, Appellants advance
a similar argument to that presented with respect to claim 1 regarding the
Examiner’s rationale to combine, inter alia, Thibadeau and Bress. For the
reasons discussed previously, we are unpersuaded of Examiner error.
Accordingly, we sustain the Examiner’s rejection of claim 3.
DECISION
We affirm the Examiner’s decision rejecting claims 1—12.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 41.50(f).
AFFIRMED
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