# Patent

## Title
Network based temporary trust extension to a remote or mobile device enabled via specialized cloud services

## Abstract

A method of executing a trusted application on a trusted security zone enabled electronic device. The method comprises responsive to a trusted security subzone not being provisioned on the electronic device, generating, by a server, a temporary trust token, transmitting the temporary trust token to the electronic device, and comparing the temporary trust token with a plurality of trust tokens stored in the electronic device to determine the trustworthiness of the temporary trust token. The method further comprises responsive to the temporary trust token being determined to be trustworthy, provisioning the non-provisioned trusted security subzone on the electronic device to be a temporary trust enablement, transmitting the trusted application through an encrypted channel to the temporary trust enablement, executing the trusted application in the temporary trust enablement, and removing the trusted application, the temporary trust enablement, and the temporary trust token when the trusted application is completed.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
Not applicable.
BACKGROUND
Network capable electronic devices are becoming increasingly prevalent in our daily lives. More and more electronic devices that did not have network capabilities are now built to be network capable. Cloud computing (network computing) where a program or application runs on a connected server or servers instead of on a local computing device is evolving into an era when high speed media content exchange is more and more involved in cloud computing systems.
SUMMARY
In an embodiment, a method of executing a trusted application on a trusted security zone enabled electronic device is disclosed. The method comprises examining a provisioning status of a trusted security subzone on the electronic device, and responsive to a trusted security subzone not being provisioned on the electronic device, generating, by a server, a temporary trust token. The method further comprises transmitting the temporary trust token to the electronic device, comparing the temporary trust token with a plurality of trust tokens stored in the electronic device to determine the trustworthiness of the temporary trust token, and responsive to the temporary trust token being determined to be trustworthy, provisioning the non-provisioned trusted security subzone on the electronic device to be a temporary trust enablement. The method further comprises transmitting the trusted application through an encrypted channel to the temporary trust enablement, executing the trusted application in the temporary trust enablement, and removing the trusted application, the temporary trust enablement, and the temporary trust token when the trusted application is completed.
In an embodiment, a method of executing a trusted application on a mobile communication device without a trusted security zone hardware partition is disclosed. The method comprises examining a provisioning status of a trusted security subzone on the mobile communication device, and responsive to no trusted security zone hardware partition being found on the mobile communication device, generating, by a server, an encrypted key. The method further comprises transmitting the encrypted key to the mobile communication device, comparing the encrypted key with a plurality of trust keys stored in the mobile communication device to determine the trustworthiness of the encrypted key, and responsive to the encrypted key being determined to be trustworthy, installing a temporary trust enablement application on the mobile communication device. The method further comprises transmitting the trusted application through an encrypted channel to the temporary trust enablement, blocking, by the temporary trust enablement, at least part of a processor of the mobile communication device every other predefined number of clock cycles to execute the trusted application, and restricting the trusted application to a subset of application programming interfaces (API) and hardware peripherals of the mobile communication device. The method further comprises releasing the at least part of the processor when the trusted application is completed and removing the trusted application, the temporary trust enablement, and the encrypted key when the trusted application is completed.
In an embodiment, a method of installing and uninstalling a trusted application on an electronic device without a trusted security zone hardware partition is disclosed. The method comprises examining a provisioning status of a trusted security subzone on the electronic device, and responsive to no trusted security zone hardware partition being found on the electronic device, installing a temporary trust enablement application on the electronic device. The method further comprises transmitting the trusted application through an encrypted channel to the temporary trust enablement and blocking, by the temporary trust enablement, at least part of a processor of the electronic device to execute the trusted application. The method further comprises releasing the at least part of the processor when the trusted application is completed, and removing the trusted application when the trusted application is completed.
These and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims.



BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts.
FIG. 1 is an illustration of a communication system according to an embodiment of the disclosure.
FIG. 2 is a flow chart illustrating a method according to an embodiment of the disclosure.
FIG. 3 is a flow chart illustrating another method according to an embodiment of the disclosure.
FIG. 4 is flow chart illustrating a third method according to an embodiment of the disclosure.
FIG. 5 is an illustration of a mobile communication device according to an embodiment of the disclosure.
FIG. 6 is a block diagram of a mobile communication device according to an embodiment of the disclosure.
FIG. 7A is a block diagram of a software architecture of a mobile communication device according to an embodiment of the disclosure.
FIG. 7B is a block diagram of another software architecture of a mobile communication device according to an embodiment of the disclosure.
FIG. 8 is a block diagram of a computer system according to an embodiment of the disclosure.



DETAILED DESCRIPTION
It should be understood at the outset that although illustrative implementations of one or more embodiments are illustrated below, the disclosed systems and methods may be implemented using any number of techniques, whether currently known or not yet in existence. The disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, but may be modified within the scope of the appended claims along with their full scope of equivalents.
With the rapid development of media creation and content distribution via wireless communication networks through cloud computing systems (Cloud), concerns are rising over security throughout the cloud systems. For example, content distribution through cloud computing systems may be unsecure and unsafe. When confidential, privacy related, and/or premium content related services are delivered through a cloud computing system, safe and secure services may be desirable. Some of these services may not desire as high security as financial transactions, medical records, or the like, but may desire higher level of secure execution than normal applications. For example, charged online gaming services, premium media streaming services, web album services, or the like, may desire some level of secure services across the cloud computing systems.
Mobile communication devices with a trusted security zone hardware partition may perform secure execution of applications with server computers maintained by a wireless communications service provider or a wireless carrier that is a home carrier for the mobile communication device. However, electronic devices, other than mobile communication devices, may not be equipped with a trusted security zone hardware partition. Those electronic devices may not be able to perform secure execution of applications or data exchange, especially with server computers maintained by a non-home carrier. The present disclosure teaches a system and method for installing a temporary trust enablement application on an electronic device for secure execution of trusted applications.
For example, a provisioning status of trusted security subzone(s) on an electronic device may be examined by a server trusted security zone on the server or by a trusted application in the server trusted security zone on the server when the electronic device requests services from the server, where those services desire secure execution or data exchange. The electronic device and the server may communicate with each other through a wired network, a wireless network, or some combination of the two. The server may be maintained by a home carrier of the electronic device or not. Based on whether or not a non-provisioned trusted security subzone is detected on the electronic device, the server may perform a variety of actions.
For example, when no trusted security zone hardware partition has been found on the electronic device, an encrypted key may be generated by the server. The encrypted key may be transmitted to the electronic device by the server. At the electronic device, the encrypted key may be compared with a plurality of stored trust keys by a kernel of an operating system of the electronic device or by a relevant application in the operating system of the electronic device to determine the trustworthiness of the encrypted key. The plurality of stored trust keys may have been generated and transmitted to the electronic device before the electronic device requested the service. The kernel of the operating system may be requested by the server to perform a variety of action for secure execution of a trusted application related to the service the electronic device requested from the server. When the encrypted key is determined by the electronic device to be trustworthy, a temporary trust enablement application may be installed by the server on the electronic device. The temporary trust enablement application may be a software application and may be executed by a processor of the electronic device. The trusted application may be transmitted by the server through an encrypted channel to the temporary trust enablement application on the electronic device.
The trusted application may be executed in the temporary trust enablement. The trusted application may be restricted to a subset of application programming interfaces (APIs) and hardware peripherals of the electronic device. Access to at least part of the processor may be blocked to other untrusted applications while the trusted application is executed. The at least part of the processor that was blocked while the trusted application was executed may be released when the trusted application execution is completed, for example when the premium media streaming is completed. The trusted application, the temporary trust enablement, and the encrypted key may be removed when the trusted application is completed.
On the other hand, when the electronic device requests services from the server, wherein those services desire secure execution, and when at least one trusted security subzone that has not been provisioned is found on the electronic device, a temporary trust token may be generated by the server. The electronic device may comprise more than one trusted security subzone, wherein some of the trusted security subzone may have been provisioned. When at least one trusted security subzone that has not been provisioned is found, a temporary trust token may be generated by the server. The temporary trust token may be transmitted to the electronic device after the temporary trust token has been generated by the server. The temporary trust token may be compared by a trusted security zone installer on the electronic device with a plurality of stored trust tokens to determine the trustworthiness of the temporary trust token. The plurality of stored trust keys may have been generated and transmitted to the electronic device before the electronic device requested the service. When the temporary trust token is determined to be trustworthy by the trusted security zone installer, the trusted security zone installer may transmit a notification to the server indicating that the trusted security subzone is ready to be provisioned. The server may then provision the non-provisioned trusted security subzone to be a temporary trust enablement, for example by transmitting a notification to the trusted security zone installer requesting the trusted security zone installer to provision the non-provisioned trusted security subzone into a temporary trust enablement.
After the non-provisioned trusted security subzone is provisioned with the temporary trust enablement, the trusted security zone installer may transmit a message or notification to the server indicating the temporary trust enablement is ready to receive a trusted application relevant to the service the electronic device requested. The server may then transmit the trusted application through an encrypted channel to the temporary trust enablement. The trusted application may be executed in the temporary trust enablement in a way similar to how a trusted application is executed in a trusted security zone, except that the trusted application has restricted access to a subset of APIs and hardware peripherals of the electronic device. The trusted application, the temporary trust enablement, and the temporary trust token may be removed when the trusted application is completed.
Turning now to FIG. 1, a communication system 100 is described. In an embodiment, the communication system 100 comprises a plurality of electronic devices 124, a data store 106, and a server 102. The server 102 may comprise a server trusted security zone 104. The electronic device 124 may comprise a processor 108, an operating system 122, and a memory 120. The memory 120 may comprise a trusted security zone portion 110 and a permissive sector 118. The trusted security zone 110 may be a trusted security subzone 110. Said in other words, the memory 120 may comprise more than one trusted security subzone 110 instead of only one trusted security zone 110. The trusted security zone 110 may comprise a plurality of trusted applications 112 and a plurality of trust keys 114. The permissive sector 118 may comprise a plurality of non-trusted applications 116. The electronic device 124 may be configured to establish a wireless or wired communication link with a network 126. The server 102 and the data store 106 may also have access to the network 126. The network 126 may comprise any combination of private and public networks.
It is understood that the system 100 may comprise any number of electronic devices 124, any number of data stores 106, and any number of servers 102. The electronic device 124 may be any of a server computer, a desktop computer, a laptop computer, a notebook computer, a tablet computer, a mobile phone, a personal digital assistant (PDA), a media player, a headset computer, a wearable computer, a game console, an Internet digital media streaming device, a television, or another network/communications capable device. The server 102 and the data store 106 may be server computers. The server 102 and the data store 106 may locate in one computer—for example a server computer, in two different computers—for example, a server computer for the server 102 and another computer for the data store 106, in multiple different computers—for example, multiple server computers for the server 102 and other multiple computers for the data store 106, or in some other combination of computers. When the server 102 and the data store 106 do not locate in one computer, the server 102 and the data store 106 may share the same wired or wireless local area network.
Non-trusted applications 116 are normal applications in the electronic device 124. When trusted applications 112 are executed in the trusted security zone 110 or a temporary trust enablement of the electronic device 124, peripherals and data of the electronic device 124 may not be accessible to the non-trusted applications 116. The non-trusted applications 116 may be stored in a permissive sector 118 in the memory 120. The permissive sector 118 of the memory 120 is the normal partition in the memory 120. When the memory 120 is not partitioned into trusted security zone(s) 110 and a permissive sector 118, the non-trusted applications 116 may be stored in the memory 120. Additionally, non-secure resources may be stored in the permissive sector 118 in the memory 120.
The server trusted security zone 104 may be stored in a memory of the server 102. The server trusted security zone 104 may communicate, manage, and/or manipulate the trusted security zone 110 on the electronic device 124. For example, the server trusted security zone 104 may provision the trusted security zone 110 to be a temporary trust enablement under predefined circumstances. After the trusted security zone 110 is provisioned to be the temporary trust enablement, the server trusted security zone 104 may communicate with relevant application(s) on the electronic device 124 and/or manage the temporary trust enablement.
For example, a security monitor 130 on the electronic device 124 may ask the server trusted security zone 104 about the trustworthiness of the temporary trust enablement. The server trusted security zone 104 or a trusted application in the server trusted security zone 104 may communicate with the security monitor 130 on the electronic device 124 to assure that the temporary trust enablement is trusted or deny that the temporary trust enablement is trusted based on the trustworthiness of the temporary trust enablement. When the temporary trust enablement is determined to be trustworthy, the server trusted security zone 104 may transmit a trusted application 112 to the electronic device 124. During the execution of the trusted application 112 on the electronic device 124, the server trusted security zone 104 and/or the security monitor 130 may monitor the status of the trusted application 112 and communicate with each other about the status of the trusted application 112.
In an embodiment, the trusted security zone 110 is more than just a segment of memory. The trusted security zone 110 may also have a dimension of processing. The trusted security zone 110 may be enabled but not provisioned at the original equipment manufacturer (OEM). When provisioned, for example at the OEM, the trusted security zone 110 may provide the secure execution environment for trusted applications 112 where only trusted applications 112 may operate, safe from attacks. The trusted security zone 110 may be implemented by partitioning both hardware and software resources of the electronic device 124 into two partitions: a secure partition and a normal partition. The secure partition may be implemented by a distinct, separate, or dedicated physical processor, usually the first processor, from the processor by which the normal partition may be implemented, usually the second processor. Alternatively, the secure partition may be implemented by a distinct, separate, or dedicated virtual processor from the virtual processor by which the normal partition may be implemented. A server trusted security zone 104 may be a server-side trusted security zone and may communicate with the trusted security zone 110.
When the trusted security zone 110 is not provisioned at the OEM, the trusted security zone 110 may be provisioned, for example by the server 102, to be a temporary trust enablement after the electronic device 124 reaches the customer side under predefined circumstances. A temporary trust enablement may perform a variety of functionality similar to a trusted security zone 110 except that a trusted application 112 in the temporary trust enablement may have restricted access to a subset of application programming interfaces (API) and hardware peripherals of the electronic device 124. Also, the temporary trust enablement, unlike a trusted security zone 110, may be allowed to exist for a limited period of time and may be removed after the execution of the trusted application 112 is completed.
In an embodiment, provisioning status of trusted security subzone(s) 110 on the electronic device 124 may be examined by the server 102, for example by the server trusted security zone 104 or by a trusted application in the server trusted security zone 104 on the server 102, under predefined circumstances. For example, the provisioning status of trusted security subzone(s) 110 may be examined after the electronic device 124 requests premium media content download or another service from the server 102. The application in the server trusted security zone 104 may transmit a message to the operating system 122 of the electronic device 124 to inquire about the provisioning status of trusted security subzone(s) 110 on the electronic device 124. The server trusted security zone 104 may take different action depending on the provisioning status of the trusted security subzone(s) 110 on the electronic device 124.
For example, when at least one trusted security (sub)zone 110 is found to not have been provisioned on the electronic device 124, a temporary trust token may be generated by the server 102. The temporary trust token may be transmitted to the electronic device 124 by the server 102. The temporary trust token may be compared by a trusted security zone installer 128 on the electronic device 124 or some other relevant trusted application in the trusted security zone hardware partition with a plurality of trust tokens or trust keys 114 stored on the electronic device 124 to determine the trustworthiness of the temporary trust token. The trust keys 114 may be stored in the same trusted security (sub)zone 110 that has been found to not be provisioned. If the temporary trust token matches any of the stored trust keys 114, the temporary trust token may be determined to be trustworthy. The trusted security zone installer 128 may transmit a notification to the server 102 indicating that the non-provisioned trusted security (sub)zone 110 is ready to be provisioned after the temporary trust token has been determined to be trustworthy.
The non-provisioned trusted security (sub)zone 110 on the electronic device 124 may be provisioned to be a temporary trust enablement by the server 102. For example, the server 102 may transmit a message or notification of provisioning the temporary trust enablement to the trusted security zone installer 128 on the electronic device 124. The provisioned temporary trust enablement may be referred to as the temporary trust enablement 110 hereinafter. After the temporary trust enablement 110 is provisioned on the electronic device 124, a trusted application 112 may be transmitted by the server 102 through an encrypted channel to the temporary trust enablement 110, for example the trusted application 112 may be encrypted and then sent to the temporary trust enablement 110. The trusted application 112 may be an application that renders the service requested by the electronic device 124 or an application among a plurality of applications that cooperate to render the service requested by the electronic device 124. The trusted application 112 may be stored in the temporary trust enablement 110 in the memory 120 and may be executed in the temporary trust enablement 110.
When the trusted application 112 is executed, only trusted application(s) 112 may operate and non-trusted applications may be prohibited from executing. Security may be further promoted by restricting access of non-trusted applications to peripherals, such as data inputs and data outputs, while the trusted application 112 is running in the temporary trusted enablement 110. The temporary trust enablement 110 may be monitored by the security monitor 130 application. For example, the security monitor 130 may monitor the execution status of the trusted application 112 and/or may communicate with the server trusted security zone 104 about the observed execution status of the trusted application 112.
When the trusted application 112 is executed in the temporary trust enablement, access to at least part of the processor 108 may be blocked, for example to non-trusted applications 116. In an embodiment, instead of executing the trusted application continuously, the trusted application 112 may be executed in a discrete manner, for example every other predefined number of clock cycles of the electronic device 124. The operating system 122 of the electronic device 124 may be suspended when the trusted application 112 is executed. However, some operating system 122 interrupt routines may still interrupt the execution of the trusted application 112, for example incoming phone rings.
The trusted application 112 may have restricted access to a subset of APIs and hardware peripherals of the electronic device 124. For example, the trusted application 112 may have restricted access to input and output ports of the electronic device 124 related to video streaming when the trusted application 112 is an application related to premium video streaming services. For example, the trusted application 112 may be an application that downloads premium media content from the server 102 or the data store 106. The trusted application 112 may be an application that uploads private media content to the server 102 or the data store 106. The trusted application 112 may be an application that provides charged online gaming services. The trusted application 112 may be an application that provides building access credentials. The trusted application 112 may be an application that provides web album services, or the like. The trusted application 112, the temporary trust enablement 110, and the temporary trust token may be removed when the trusted application 112 is execution completed, for example when the premium video streaming is completed.
On the other hand, if no trusted security zone hardware partition is found on the electronic device 124 when the provisioning status of trusted security subzone(s) 110 on the electronic device 124 is examined by the server 102, an encrypted key may be generated by the server 102. When no trusted security zone hardware partition is found on the electronic device 124, the memory 120 may comprise only a permissive sector. A kernel of the operating system 122 may be utilized to block the at least part of the processor 108 when a trusted application transmitted to the electronic device 124 is executed. The server 102 may interrogate the electronic device 124 to determine which suspend modes of the processor 108 the kernel of the operating system 122 supports. When the suspend modes are determined and transmitted back to the server 102, the server 102 may transmit the encrypted key to the electronic device 124.
The encrypted key may be compared with a plurality of stored trust keys 114 to determine the trustworthiness of the encrypted key, for example by the kernel of the operating system 122 of the electronic device 124 or by a relevant application in the operating system 122. The trusted keys 114 may be stored in the memory 120 of the electronic device 124. When the encrypted key matches any of the plurality of the stored trust keys 114, the encrypted key may be determined to be trustworthy. The operating system 122 or the application in environment supported by the operating system 122 may transmit a notification or message to the server 102 indicating that the electronic device 124 is ready to be installed with a temporary trust enablement application after the encrypted key is determined to be trustworthy. The temporary trust enablement application may be installed on the electronic device 124 by the server 102. For example, the server 102 may transmit a notification to the operating system 122 to request the operating system 122 or the application in the operating system 122 to install the temporary trust enablement application. The temporary trust enablement application may be a software application and may be executed by the processor 108.
A trusted application 112 may be transmitted by the server 102 through an encrypted channel to the temporary trust enablement application on the electronic device 124. Access to at least part of the processor 108 of the electronic device 124 may be blocked, for example to non-trusted applications 116, by the temporary trust enablement when the trusted application 112 is executed. The trusted application 112 may not execute continuously. Instead, the trusted application 112 may be executed every other predefined number of clock cycles of the electronic device 124. Thus, the at least part of the processor 108 may be blocked every other predefined number of clock cycles while the trusted application 112 is executed. However, some operating system 122 interrupt routines may still interrupt the execution of the trusted application 112, for example incoming phone rings. The trusted application 112 may be restricted to a subset of APIs and hardware peripherals of the electronic device 124.
The temporary trust enablement application may block access to the at least part of the processor 108 to non-trusted applications 116 while the trusted application 112 is executed. Alternatively, the kernel of the operating system 122 may be utilized by the temporary trust enablement to block the at least part of the processor 108. The at least part of the processor 108 that was blocked while the trusted application was executed may be released when the trusted application 112 execution is completed. The trusted application 112, the temporary trust enablement, and the encrypted key may be removed when the trusted application 112 execution is completed. When a second trusted application is about to be executed on the electronic device 124, a second encrypted key may be generated by the server 102 and transmitted to the electronic device 124 for trustworthiness validation.
Turning now to FIG. 2, a method 200 is described. At block 202, a provisioning status of a trusted security subzone on the electronic device is examined. For example, provisioning statuses of trusted security subzones 110 on the electronic device 124 may be examined by the server 102. At block 204, responsive to a trusted security subzone not being provisioned on the electronic device, a temporary trust token is generated by a server. For example, when a trusted security subzone 110 is found to have not been provisioned on the electronic device 124, a temporary trust token may be generated by the server 102, for example by the server trusted security zone 104 or a trusted application in the server trusted security zone 104. At block 206, the temporary trust token is transmitted to the electronic device 124.
At block 208, the temporary trust token is compared with a plurality of trust tokens stored in the electronic device to determine the trustworthiness of the temporary trust token. For example, the temporary trust token may be compared with a plurality of stored trust tokens or trust keys 114 to determine the trustworthiness of the temporary trust token. The stored trust keys 114 may have been transmitted from the server 102 to the electronic device 124 before examining the provisioning status of trusted security subzones 110 on the electronic device 124. For example, when the user or owner of an electronic device 124 travels to a building and desires access to the building, a trusted application may be installed on the electronic device 124 for the building access. Before the user of the electronic device 124 arrives at the building, the server 102 may transmit at least one trust key to the electronic device 124. The trust key(s) from the server 102 may be stored in non-provisioned trusted security subzone(s) 110.
At block 210, responsive to the temporary trust token being determined to be trustworthy, the non-provisioned trusted security subzone 110 on the electronic device 124 is provisioned to be a temporary trust enablement 110. At block 212, the trusted application 112 is transmitted through an encrypted channel to the temporary trust enablement 110. At block 214, the trusted application 112 is executed in the temporary trust enablement 110. At block 216, the trusted application 112, the temporary trust enablement 110, and the temporary trust token are removed when the trusted application is completed.
Turning now to FIG. 3, a method 300 is described. At block 302, a provisioning status of a trusted security subzone on the mobile communication device 124 is examined. In FIG. 3, the mobile communication device 124 may be referred to as a mobile communication device 124. At block 304, responsive to no trusted security zone hardware partition being found on the mobile communication device 124, an encrypted key is generated by a server 102. At block 306, the encrypted key is transmitted to the mobile communication device 124.
At block 308, the temporary trust token is compared with a plurality of trust keys 114 stored in the mobile communication device to determine the trustworthiness of the encrypted key. At block 310, responsive to the encrypted key being determined to be trustworthy, a temporary trust enablement application is installed on the mobile communication device 124. At block 312, the trusted application 112 is transmitted through an encrypted channel to the temporary trust enablement.
At block 314, at least part of a processor 108 of the mobile communication device 124 is blocked by the temporary trust enablement every other predefined number of clock cycles to execute the trusted application 112. At block 316, the trusted application 112 is restricted to a subset of application programming interfaces (API) and hardware peripherals of the mobile communication device 124. At block 318, the at least part of the processor 108 is released when the trusted application 112 is completed. At block 320, the trusted application 112, the temporary trust enablement, and the encrypted key are removed when the trusted application 112 is completed.
Turning now to FIG. 4, a method 410 is described. At block 401, a provisioning status of a trusted security subzone on the electronic device 124 is examined. At block 403, responsive to no trusted security zone hardware partition being found on the electronic device 124, a temporary trust enablement application is installed on the electronic device 124. At block 406, the trusted application 112 is transmitted through an encrypted channel to the temporary trust enablement. At block 408, at least part of a processor 108 of the electronic device 124 is blocked by the temporary trust enablement to execute the trusted application 112. At block 410, the at least part of the processor 108 is released when the trusted application 112 is completed. At block 412, the trusted application 112 is removed when the trusted application 112 is completed.
FIG. 5 depicts the mobile device 400, which is operable for implementing aspects of the present disclosure, but the present disclosure should not be limited to these implementations. Though illustrated as a mobile phone, the mobile device 400 may take various forms including a wireless handset, a pager, a personal digital assistant (PDA), a gaming device, or a media player. The mobile device 400 includes a display 402 and a touch-sensitive surface and/or keys 404 for input by a user. The mobile device 400 may present options for the user to select, controls for the user to actuate, and/or cursors or other indicators for the user to direct. The mobile device 400 may further accept data entry from the user, including numbers to dial or various parameter values for configuring the operation of the handset. The mobile device 400 may further execute one or more software or firmware applications in response to user commands. These applications may configure the mobile device 400 to perform various customized functions in response to user interaction. Additionally, the mobile device 400 may be programmed and/or configured over-the-air, for example from a wireless base station, a wireless access point, or a peer mobile device 400. The mobile device 400 may execute a web browser application which enables the display 402 to show a web page. The web page may be obtained via wireless communications with a base transceiver station, a wireless network access node, a peer mobile device 400 or any other wireless communication network or system.
FIG. 6 shows a block diagram of the mobile device 400. While a variety of known components of handsets are depicted, in an embodiment a subset of the listed components and/or additional components not listed may be included in the mobile device 400. The mobile device 400 includes a digital signal processor (DSP) 502 and a memory 504. As shown, the mobile device 400 may further include an antenna and front end unit 506, a radio frequency (RF) transceiver 508, a baseband processing unit 510, a microphone 512, an earpiece speaker 514, a headset port 516, an input/output interface 518, a removable memory card 520, a universal serial bus (USB) port 522, an infrared port 524, a vibrator 526, a keypad 528, a touch screen liquid crystal display (LCD) with a touch sensitive surface 530, a touch screen/LCD controller 532, a camera 534, a camera controller 536, and a global positioning system (GPS) receiver 538. In an embodiment, the mobile device 400 may include another kind of display that does not provide a touch sensitive screen. In an embodiment, the DSP 502 may communicate directly with the memory 504 without passing through the input/output interface 518. Additionally, in an embodiment, the mobile device 400 may comprise other peripheral devices that provide other functionality.
The DSP 502 or some other form of controller or central processing unit operates to control the various components of the mobile device 400 in accordance with embedded software or firmware stored in memory 504 or stored in memory contained within the DSP 502 itself. In addition to the embedded software or firmware, the DSP 502 may execute other applications stored in the memory 504 or made available via information carrier media such as portable data storage media like the removable memory card 520 or via wired or wireless network communications. The application software may comprise a compiled set of machine-readable instructions that configure the DSP 502 to provide the desired functionality, or the application software may be high-level software instructions to be processed by an interpreter or compiler to indirectly configure the DSP 502.
The DSP 502 may communicate with a wireless network via the analog baseband processing unit 510. In some embodiments, the communication may provide Internet connectivity, enabling a user to gain access to content on the Internet and to send and receive e-mail or text messages. The input/output interface 518 interconnects the DSP 502 and various memories and interfaces. The memory 504 and the removable memory card 520 may provide software and data to configure the operation of the DSP 502. Among the interfaces may be the USB port 522 and the infrared port 524. The USB port 522 may enable the mobile device 400 to function as a peripheral device to exchange information with a personal computer or other computer system. The infrared port 524 and other optional ports such as a Bluetooth® interface or an IEEE 802.11 compliant wireless interface may enable the mobile device 400 to communicate wirelessly with other nearby handsets and/or wireless base stations. In an embodiment, the device 400 may comprise a near field communication (NFC) transceiver. The NFC transceiver may be used to complete payment transactions with point-of-sale terminals or other communications exchanges. In an embodiment, the device 400 may comprise a radio frequency identify (RFID) reader and/or writer device.
The keypad 528 couples to the DSP 502 via the input/output interface 518 to provide one mechanism for the user to make selections, enter information, and otherwise provide input to the mobile device 400. Another input mechanism may be the touch screen LCD 530, which may also display text and/or graphics to the user. The touch screen LCD controller 532 couples the DSP 502 to the touch screen LCD 530. The GPS receiver 538 is coupled to the DSP 502 to decode global positioning system signals, thereby enabling the mobile device 400 to determine its position.
FIG. 7A illustrates a software environment 602 that may be implemented by the DSP 502. The DSP 502 executes operating system software 604 that provides a platform from which the rest of the software operates. The operating system software 604 may provide a variety of drivers for the handset hardware with standardized interfaces that are accessible to application software. The operating system software 604 may be coupled to and interact with application management services (AMS) 606 that transfer control between applications running on the mobile device 400. Also shown in FIG. 7A are a web browser application 608, a media player application 610, and JAVA applets 612. The web browser application 608 may be executed by the mobile device 400 to browse content and/or the Internet, for example when the mobile device 400 is coupled to a network via a wireless link. The web browser application 608 may permit a user to enter information into forms and select links to retrieve and view web pages. The media player application 610 may be executed by the mobile device 400 to play audio or audiovisual media. The JAVA applets 612 may be executed by the mobile device 400 to provide a variety of functionality including games, utilities, and other functionality.
FIG. 7B illustrates an alternative software environment 620 that may be implemented by the DSP 502. The DSP 502 executes operating system kernel (OS kernel) 628 and an execution runtime 630. The DSP 502 executes applications 622 that may execute in the execution runtime 630 and may rely upon services provided by the application framework 624. Applications 622 and the application framework 624 may rely upon functionality provided via the libraries 626.
A trusted security zone provides chipsets with a hardware root of trust, a secure execution environment for applications, and secure access to peripherals. A hardware root of trust means the chipset should only execute programs intended by the device manufacturer or vendor and resists software and physical attacks, and therefore remains trusted to provide the intended level of security. The chipset architecture is designed to promote a programmable environment that allows the confidentiality and integrity of assets to be protected from specific attacks. Trusted security zone capabilities are becoming features in both wireless and fixed hardware architecture designs. Providing the trusted security zone in the main mobile device chipset and protecting the hardware root of trust removes the need for separate secure hardware to authenticate the device or user. To ensure the integrity of the applications requiring trusted data, such as a mobile financial services application, the trusted security zone also provides the secure execution environment where only trusted applications can operate, safe from attacks. Security is further promoted by restricting access of non-trusted applications to peripherals, such as data inputs and data outputs, while a trusted application is running in the secure execution environment. In an embodiment, the trusted security zone may be conceptualized as hardware assisted security.
A complete Trusted Execution Environment (TEE) may be implemented through the use of the trusted security zone hardware and software architecture. The Trusted Execution Environment is an execution environment that is parallel to the execution environment of the main mobile device operating system. The Trusted Execution Environment and/or the trusted security zone may provide a base layer of functionality and/or utilities for use of applications that may execute in the trusted security zone. For example, in an embodiment, trust tokens may be generated by the base layer of functionality and/or utilities of the Trusted Execution Environment and/or trusted security zone for use in trusted end-to-end communication links to document a continuity of trust of the communications. Through standardization of application programming interfaces (APIs), the Trusted Execution Environment becomes a place to which scalable deployment of secure services can be targeted. A device which has a chipset that has a Trusted Execution Environment on it may exist in a trusted services environment, where devices in the trusted services environment are trusted and protected against attacks. The Trusted Execution Environment can be implemented on mobile phones and tablets as well as extending to other trusted devices such as personal computers, servers, sensors, medical devices, point-of-sale terminals, industrial automation, handheld terminals, automotive, etc.
The trusted security zone is implemented by partitioning all of the hardware and software resources of the mobile device into two partitions: a secure partition and a normal partition. The secure partition may be implemented by a first physical processor, and the normal partition may be implemented by a second physical processor. Alternatively, the secure partition may be implemented by a first virtual processor, and the normal partition may be implemented by a second virtual processor. Placing sensitive resources in the secure partition can protect against possible attacks on those resources. For example, resources such as trusted software applications may run in the secure partition and have access to hardware peripherals such as a touchscreen or a secure location in memory. Less secure peripherals such as wireless radios may be disabled completely while the secure partition is being accessed, while other peripherals may only be accessed from the secure partition. While the secure partition is being accessed through the Trusted Execution Environment, the main mobile operating system in the normal partition is suspended, and applications in the normal partition are prevented from accessing the secure peripherals and data. This prevents corrupted applications or malware applications from breaking the trust of the device.
The trusted security zone is implemented by partitioning the hardware and software resources to exist in a secure subsystem which is not accessible to components outside the secure subsystem. The trusted security zone is built into the processor architecture at the time of manufacture through hardware logic present in the trusted security zone which enables a perimeter boundary between the secure partition and the normal partition. The trusted security zone may only be manipulated by those with the proper credential and, in an embodiment, may not be added to the chip after it is manufactured. Software architecture to support the secure partition may be provided through a dedicated secure kernel running trusted applications. Trusted applications are independent secure applications which can be accessed by normal applications through an application programming interface in the Trusted Execution Environment on a chipset that utilizes the trusted security zone.
In an embodiment, the normal partition applications run on a first virtual processor, and the secure partition applications run on a second virtual processor. Both virtual processors may run on a single physical processor, executing in a time-sliced fashion, removing the need for a dedicated physical security processor. Time-sliced execution comprises switching contexts between the two virtual processors to share processor resources based on tightly controlled mechanisms such as secure software instructions or hardware exceptions. The context of the currently running virtual processor is saved, the context of the virtual processor being switched to is restored, and processing is restarted in the restored virtual processor. Time-sliced execution protects the trusted security zone by stopping the execution of the normal partition while the secure partition is executing.
The two virtual processors context switch via a processor mode called monitor mode when changing the currently running virtual processor. The mechanisms by which the processor can enter monitor mode from the normal partition are tightly controlled. The entry to monitor mode can be triggered by software executing a dedicated instruction, the Secure Monitor Call (SMC) instruction, or by a subset of the hardware exception mechanisms such as hardware interrupts, which can be configured to cause the processor to switch into monitor mode. The software that executes within monitor mode then saves the context of the running virtual processor and switches to the secure virtual processor.
The trusted security zone runs a separate operating system that is not accessible to the device users. For security purposes, the trusted security zone is not open to users for installing applications, which means users do not have access to install applications in the trusted security zone. This prevents corrupted applications or malware applications from executing powerful instructions reserved to the trusted security zone and thus preserves the trust of the device. The security of the system is achieved at least in part by partitioning the hardware and software resources of the mobile phone so they exist in one of two partitions, the secure partition for the security subsystem and the normal partition for everything else. Placing the trusted security zone in the secure partition and restricting access from the normal partition protects against software and basic hardware attacks. Hardware logic ensures that no secure partition resources can be accessed by the normal partition components or applications. A dedicated secure partition operating system runs in a virtual processor separate from the normal partition operating system that likewise executes in its own virtual processor. Users may install applications on the mobile device which may execute in the normal partition operating system described above. The trusted security zone runs a separate operating system for the secure partition that is installed by the mobile device manufacturer or vendor, and users are not able to install new applications in or alter the contents of the trusted security zone.
FIG. 8 illustrates a computer system 380 suitable for implementing one or more embodiments disclosed herein. The computer system 380 includes a processor 382 (which may be referred to as a central processor unit or CPU) that is in communication with memory devices including secondary storage 384, read only memory (ROM) 386, random access memory (RAM) 388, input/output (I/O) devices 390, and network connectivity devices 392. The processor 382 may be implemented as one or more CPU chips.
It is understood that by programming and/or loading executable instructions onto the computer system 380, at least one of the CPU 382, the RAM 388, and the ROM 386 are changed, transforming the computer system 380 in part into a particular machine or apparatus having the novel functionality taught by the present disclosure. It is fundamental to the electrical engineering and software engineering arts that functionality that can be implemented by loading executable software into a computer can be converted to a hardware implementation by well-known design rules. Decisions between implementing a concept in software versus hardware typically hinge on considerations of stability of the design and numbers of units to be produced rather than any issues involved in translating from the software domain to the hardware domain. Generally, a design that is still subject to frequent change may be preferred to be implemented in software, because re-spinning a hardware implementation is more expensive than re-spinning a software design. Generally, a design that is stable that will be produced in large volume may be preferred to be implemented in hardware, for example in an application specific integrated circuit (ASIC), because for large production runs the hardware implementation may be less expensive than the software implementation. Often a design may be developed and tested in a software form and later transformed, by well-known design rules, to an equivalent hardware implementation in an application specific integrated circuit that hardwires the instructions of the software. In the same manner as a machine controlled by a new ASIC is a particular machine or apparatus, likewise a computer that has been programmed and/or loaded with executable instructions may be viewed as a particular machine or apparatus.
The secondary storage 384 is typically comprised of one or more disk drives or tape drives and is used for non-volatile storage of data and as an over-flow data storage device if RAM 388 is not large enough to hold all working data. Secondary storage 384 may be used to store programs which are loaded into RAM 388 when such programs are selected for execution. The ROM 386 is used to store instructions and perhaps data which are read during program execution. ROM 386 is a non-volatile memory device which typically has a small memory capacity relative to the larger memory capacity of secondary storage 384. The RAM 388 is used to store volatile data and perhaps to store instructions. Access to both ROM 386 and RAM 388 is typically faster than to secondary storage 384. The secondary storage 384, the RAM 388, and/or the ROM 386 may be referred to in some contexts as computer readable storage media and/or non-transitory computer readable media.
I/O devices 390 may include printers, video monitors, liquid crystal displays (LCDs), touch screen displays, keyboards, keypads, switches, dials, mice, track balls, voice recognizers, card readers, paper tape readers, or other well-known input devices.
The network connectivity devices 392 may take the form of modems, modem banks, Ethernet cards, universal serial bus (USB) interface cards, serial interfaces, token ring cards, fiber distributed data interface (FDDI) cards, wireless local area network (WLAN) cards, radio transceiver cards such as code division multiple access (CDMA), global system for mobile communications (GSM), long-term evolution (LTE), worldwide interoperability for microwave access (WiMAX), and/or other air interface protocol radio transceiver cards, and other well-known network devices. These network connectivity devices 392 may enable the processor 382 to communicate with the Internet or one or more intranets. With such a network connection, it is contemplated that the processor 382 might receive information from the network, or might output information to the network in the course of performing the above-described method steps. Such information, which is often represented as a sequence of instructions to be executed using processor 382, may be received from and outputted to the network, for example, in the form of a computer data signal embodied in a carrier wave.
Such information, which may include data or instructions to be executed using processor 382 for example, may be received from and outputted to the network, for example, in the form of a computer data baseband signal or signal embodied in a carrier wave. The baseband signal or signal embedded in the carrier wave, or other types of signals currently used or hereafter developed, may be generated according to several methods well known to one skilled in the art. The baseband signal and/or signal embedded in the carrier wave may be referred to in some contexts as a transitory signal.
The processor 382 executes instructions, codes, computer programs, scripts which it accesses from hard disk, floppy disk, optical disk (these various disk based systems may all be considered secondary storage 384), ROM 386, RAM 388, or the network connectivity devices 392. While only one processor 382 is shown, multiple processors may be present. Thus, while instructions may be discussed as executed by a processor, the instructions may be executed simultaneously, serially, or otherwise executed by one or multiple processors. Instructions, codes, computer programs, scripts, and/or data that may be accessed from the secondary storage 384, for example, hard drives, floppy disks, optical disks, and/or other device, the ROM 386, and/or the RAM 388 may be referred to in some contexts as non-transitory instructions and/or non-transitory information.
In an embodiment, the computer system 380 may comprise two or more computers in communication with each other that collaborate to perform a task. For example, but not by way of limitation, an application may be partitioned in such a way as to permit concurrent and/or parallel processing of the instructions of the application. Alternatively, the data processed by the application may be partitioned in such a way as to permit concurrent and/or parallel processing of different portions of a data set by the two or more computers. In an embodiment, virtualization software may be employed by the computer system 380 to provide the functionality of a number of servers that is not directly bound to the number of computers in the computer system 380. For example, virtualization software may provide twenty virtual servers on four physical computers. In an embodiment, the functionality disclosed above may be provided by executing the application and/or applications in a cloud computing environment. Cloud computing may comprise providing computing services via a network connection using dynamically scalable computing resources. Cloud computing may be supported, at least in part, by virtualization software. A cloud computing environment may be established by an enterprise and/or may be hired on an as-needed basis from a third party provider. Some cloud computing environments may comprise cloud computing resources owned and operated by the enterprise as well as cloud computing resources hired and/or leased from a third party provider.
In an embodiment, some or all of the functionality disclosed above may be provided as a computer program product. The computer program product may comprise one or more computer readable storage medium having computer usable program code embodied therein to implement the functionality disclosed above. The computer program product may comprise data structures, executable instructions, and other computer usable program code. The computer program product may be embodied in removable computer storage media and/or non-removable computer storage media. The removable computer readable storage medium may comprise, without limitation, a paper tape, a magnetic tape, magnetic disk, an optical disk, a solid state memory chip, for example analog magnetic tape, compact disk read only memory (CD-ROM) disks, floppy disks, jump drives, digital cards, multimedia cards, and others. The computer program product may be suitable for loading, by the computer system 380, at least portions of the contents of the computer program product to the secondary storage 384, to the ROM 386, to the RAM 388, and/or to other non-volatile memory and volatile memory of the computer system 380. The processor 382 may process the executable instructions and/or data structures in part by directly accessing the computer program product, for example by reading from a CD-ROM disk inserted into a disk drive peripheral of the computer system 380. Alternatively, the processor 382 may process the executable instructions and/or data structures by remotely accessing the computer program product, for example by downloading the executable instructions and/or data structures from a remote server through the network connectivity devices 392. The computer program product may comprise instructions that promote the loading and/or copying of data, data structures, files, and/or executable instructions to the secondary storage 384, to the ROM 386, to the RAM 388, and/or to other non-volatile memory and volatile memory of the computer system 380.
In some contexts, the secondary storage 384, the ROM 386, and the RAM 388 may be referred to as a non-transitory computer readable medium or a computer readable storage media. A dynamic RAM embodiment of the RAM 388, likewise, may be referred to as a non-transitory computer readable medium in that while the dynamic RAM receives electrical power and is operated in accordance with its design, for example during a period of time during which the computer system 380 is turned on and operational, the dynamic RAM stores information that is written to it. Similarly, the processor 382 may comprise an internal RAM, an internal ROM, a cache memory, and/or other internal non-transitory storage blocks, sections, or components that may be referred to in some contexts as non-transitory computer readable media or computer readable storage media.
While several embodiments have been provided in the present disclosure, it should be understood that the disclosed systems and methods may be embodied in many other specific forms without departing from the spirit or scope of the present disclosure. The present examples are to be considered as illustrative and not restrictive, and the intention is not to be limited to the details given herein. For example, the various elements or components may be combined or integrated in another system or certain features may be omitted or not implemented.
Also, techniques, systems, subsystems, and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other items shown or discussed as directly coupled or communicating with each other may be indirectly coupled or communicating through some interface, device, or intermediate component, whether electrically, mechanically, or otherwise. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the spirit and scope disclosed herein.

## Claims

1. A method of executing a trusted application on a trusted security zone enabled electronic device, comprising:
examining a provisioning status of a trusted security subzone on the electronic device;
responsive to a trusted security subzone not being provisioned on the electronic device, generating, by a server, a temporary trust token;
transmitting the temporary trust token to the electronic device;
comparing the temporary trust token with a plurality of trust tokens stored in the electronic device to determine the trustworthiness of the temporary trust token;
responsive to the temporary trust token being determined to be trustworthy, provisioning the non-provisioned trusted security subzone on the electronic device to be a temporary trust enablement;
transmitting the trusted application through an encrypted channel to the temporary trust enablement;
executing the trusted application in the temporary trust enablement, wherein the temporary trust enablement selectively blocks at least part of a processor of the electronic device to execute the trusted application, and wherein the trusted application has restricted access to a subset of application programming interfaces and hardware peripherals of the electronic device;
releasing the at least part of the processor when the trusted application is completed; and
removing the trusted application, the temporary trust enablement, and the temporary trust token when the trusted application is completed.

2. The method of claim 1, further comprising, monitoring, by a security monitor application, the temporary trust enablement.

3. The method of claim 1, wherein the trusted application is an application that downloads premium media content from the server.

4. The method of claim 1, wherein the trusted application is an application that uploads private media content to the server.

5. The method of claim 1, wherein the processor of the electronic device operates at a clock speed based on a predefined number of clock cycles, and the trusted application is executed in the temporary trust enablement during every other clock cycle.

6. The method of claim 5, wherein an operating system of the electronic device is suspended when the trusted application is executed.

7. A method of executing a trusted application on a mobile communication device without a trusted security zone hardware partition, comprising:
examining a provisioning status of a trusted security subzone on the mobile communication device;
responsive to no trusted security zone hardware partition being found on the mobile communication device, generating, by a server, an encrypted key;
transmitting the encrypted key to the mobile communication device;
comparing the encrypted key with a plurality of trust keys stored in the mobile communication device to determine the trustworthiness of the encrypted key;
responsive to the encrypted key being determined to be trustworthy, installing a temporary trust enablement application on the mobile communication device;
transmitting the trusted application through an encrypted channel to the temporary trust enablement;
blocking, by the temporary trust enablement, at least part of a processor of the mobile communication device every other predefined number of clock cycles to execute the trusted application;
restricting the trusted application to a subset of application programming interfaces and hardware peripherals of the mobile communication device;
releasing the at least part of the processor when the trusted application is completed; and
removing the trusted application, the temporary trust enablement, and the encrypted key when the trusted application is completed.

8. The method of claim 7, further comprising, monitoring, by a server trusted security zone on the server, the temporary trust enablement application.

9. The method of claim 7, wherein a kernel of an operating system of the electronic device is utilized by the temporary trust enablement to block the at least part of the processor.

10. The method of claim 9, wherein the server interrogates the electronic device to determine which suspend modes of the processor the kernel supports.

11. The method of claim 10, wherein when the suspend modes is determined, the server transmits the encrypted key to the electronic device.

12. The method of claim 7, wherein the server trusted security zone installs the temporary trust enablement application on the electronic device.

13. The method of claim 7, wherein the electronic device is one of a server computer, a desktop computer, a laptop computer, a notebook computer, a tablet computer, a mobile phone, a personal digital assistant, a media player, a headset computer, a wearable computer, a game console, an Internet digital media streaming device, a television, or another network/communications capable device.