EP2361416A1

EP2361416A1 - Secure storage device

Info

Publication number: EP2361416A1
Application number: EP09803915A
Authority: EP
Inventors: Isaac Hadad; Zvi Gam; Abraham Dahan
Original assignee: Walletex Microelectronics Ltd
Current assignee: Walletex Microelectronics Ltd
Priority date: 2008-11-10
Filing date: 2009-11-10
Publication date: 2011-08-31
Also published as: WO2010052722A1

Abstract

The present invention provides a secure handheld portable storage device comprising a nonvolatile memory, data communication connectivity means, a secure processor operated with a secure operating system, and interfacing means for interfacing between the secure processor and a data processing system and the nonvolatile memory, wherein the secure processor comprises a cpu, a secure memory, and optionally PKI, and/or encryption/decryption means.

Description

SECURE STORAGE DEVICE

Field of the Invention

The present invention generally relates to a handheld portable storage device having smart card capabilities and a relatively large rewritable memory which may be securely accessed by cryptographic means.

Background of the Invention

The present invention relates to a secure handheld portable storage device having smart card capabilities and a relatively large memory.

There are many types of portable memory devices available nowadays, which usually have no processing means, and which memories are accessed directly e.g., straight memory cards, and which have no data processing capabilities. These types of memory cards are not capable of identifying themselves, and their memories can be easily copied.

Some level of security is provided by protected memory devices which comprise access control circuitry for controlling card memory access. However, the security provided by these memory cards is usually limited to read/write access permission, usually through a password or system key, and thus they are not considered to be tamper-proof.

Smart card chip cards are handheld portable cards comprising processing means. These cards often comprise a tamper- resistant security system having a secure memory and secured cryptographic processor. These chip cards are designed to be tamper resistant, and thus often used for securely holding encryption keys, for digital signature and secure identification (e.g., ATM cards, SIMs) .

Smart cards may be categorized as stored value memory cards (e.g., telephone cards), multifunction smart cards, and contactless cards (communicates the reader by means of RFID induction) , which are equipped with chips powered with cryptographic PKI (public key infrastructure) functions, but all of which also have relatively little or no memory left for any other function, low processing capabilities, and relatively low communication rates.

Smart cards are designed to allow utilization of private cryptographic keys without exposing them to the external world. For example, multifunction smart cards have data processing means which manages data in organized file structures via a card operating system (COS), which controls memory access.

The smart card operating system is designed to avoid exposing the secret data such as cryptographic keys and passwords stored in the card memory. Namely, this operating system does not include commands that will reveal the values of such secret data, thereby preventing such secret data from being accessed via the smart card operating system (OS) . Further measures are often taken to secure the smart card against disassembly tampering.

WO 2009/130538 describes a storage device comprising a mass storage memory, a main controller capable of communicating with a personal computer over data communication interfacing means, and a smart card controller, wherein the main controller govern the operation of the device and its communication with the personal computer and the smartcard controller governs the access to the mass storage memory. Although this storage device may serve as secure storage means its operation speed is limited since the communicated data is firstly handled by the smartcard controller and thereafter by main controller before communicating it to the personal computer, and due to the relatively slow processing speeds of conventional smartcard chips.

The aforementioned devices have not yet provided suitable solutions for securely storing relatively large quantities of data in a portable handheld device.

It is therefore an object of the present invention to provide a storage device having relatively large memory capacity that can be protected against unauthorized access by cryptographic means .

It is another object of the present invention to provide a secure handheld portable storage device having mass storage memory that may be accessed via smart card protocols over conventional data communication links.

It is a further object of the present invention to provide a secure handheld storage device having smart card capabilities and increased processing capabilities and data communication rates .

Other objects and advantages of the invention will become apparent as the description proceeds. Summary of the Invention

It has now been found that it is possible to construct a handheld portable storage device (also referred to herein as a storage device) having substantially large memory capacity and smart card functionality with improved processing capabilities and data communication speeds, wherein said storage device is accessible via conventional data communication connectivity means and the data stored in its memory may be protected cryptographically without suffering the limitations associated with smart cards chips. This new storage device may therefore be used for storing and reading privileged and non-privileged data stored therein via conventional data processing systems (e.g., personal computers - PCs), where said privileged data is preferably stored in encrypted form and may be accessed once user identification is verified by means of the smart card functionality provided therein. Once user identification is verified, privileged data items may be securely stored in the device memory in an encrypted form, or decrypted and read therefrom.

The term privileged data used herein refers to classified information which may be accessed by authorized individuals only. The privileged data may comprise, but is not limited to, any type of private, sensitive, confidential, and/or proprietary information (e.g., financial/banking information, medical information) .

The term data communication connectivity means used herein refers to the means needed for establishing the physical and electrical connection required for allowing data communication with a computer system. Typically this term refers to the communication connectors (or ports) and any additional wiring or circuitry which may be further needed for their operation. The term data communication link used herein refers to the data communication established between data processing devices once connectivity in the physical and the logical layers is obtained between them.

The term secure processor used herein refers to a type of processors having internal memory that can not be accessed by traditional user/privileged processor states (secure memory), said internal memory is typically used for storing secret information, such as but not limited to passwords and cryptographic key, which may be accessed by safe routines employing special processor states. Preferably, the secure processor complies with security criteria defined by a secure operating system to be used therewith. Typically, such secure processors further comprise protections against hardware and software attacks.

The term secure operating system used herein refers to a type of hardware-based operating system wherein the security is based on hardware support capable of authenticating users and preventing read and write access to data and thereby protect against tampering and unauthorized access. The secure operating system thus requires a suitable secure processor for running it that is capable of providing the needed hardware support .

The present invention is thus primarily directed to a handheld portable storage device comprising a nonvolatile read/write memory, data communication connectivity means, and secure processor means comprising a cpu (central processing means), a secure memory, PKI functionality (optional) , encryption/decryption means (optional) , and suitable interfacing means for interfacing between said secure processor and a data processing system via said data communication connectivity means, and for interfacing between said secure processor and said nonvolatile memory, a secure operating system (e.g., smart card operating system complying with the ISO 7816 specification standard, or a modified version thereof) to be ran by said secure processor, user identification data such as passwords and cryptographic keys stored in the secure memory (also referred to herein as secret data) , and file management information and other data and executable code stored in the nonvolatile memory and which is needed for its operation.

The hand held storage device may optionally further comprise a hash (or MAC) module implemented in the secure processor by hardware or firmware, or by a combination thereof, adapted for generating digital signatures, which may be utilized for testing the validity of the data stored in the nonvolatile memory by generating a digital signature for data items stored therein and storing the same in the secure memory. In this way, whenever needed, the integrity of stored data items may be verified by generating a digital signature for a stored data item and comparing it with the corresponding digital signature stored in the secure memory.

According to one preferred embodiment of the invention the storage device is implemented in a form of a storage card having geometrical dimensions of a credit card, but of course, any other suitable geometry may be used instead. Advantageously, the storage device can be accessed for securely reading and/or storing data items by means of conventional data communication connectivity means provided therein by employing its smart card functionality for verifying user's identity, such that smart card reader may not be needed. Furthermore, by utilizing s suitable secure processor in the storage device the processing capabilities of the device can be substantially improved, such that the resulting storage device may appear and behave as a smart card, but with substantially greater memory capacity and improved processing power and data communication speeds.

According to one non-limiting example, a preferred embodiment of the invention may comprise a nonvolatile memory implemented by a flash memory having 32GB, data communication connector, and a secure processor comprising secure memory, cpu, interfacing means suitable for interfacing between said cpu and a data processing system (e.g., PC) via the data communication connector and between said cpu and said flash memory, PKI (e.g., RSA) functionality, hash (e.g., shal) (or mac) module, and encryption decryption means (e.g., AES), wherein said secure processor is operated by a secure operating system (e.g., smartcard operating system) stored in its secure memory, said secure memory further comprises secret data (e.g., passwords, cryptographic keys) and other information needed for the operation of the device, thereby providing a storage device having smart card functionality wherein the storage device is having substantially improved processing capabilities, increased memory capacity and improved data communication rates in comparison to conventional smart card devices. Preferably, the data communication connectivity is implemented employing the USB (universal serial bus) protocol and connectivity, such that the storage device may be accessed by means of conventional USB hosts systems. It is understood that the storage device of the invention may be also accessed via a smart card connector optionally provided therein. Optionally, the storage device may be accessed via a USB connector or a smart card connector provided thereon, for example as described in WO 2007/138570 of the same applicant hereof, the description of which is incorporated herein by reference.

According to a specific preferred embodiment the storage device of the invention is a type of a flash card storage device managed by a secure processor running a smart card operating system complying with the ISO 7816 standard, or a modified version thereof, thus providing said flash card storage device smart card security features, improved processing capabilities, augmented memory capacity, and improved data communication rates, wherein data items stored in said flash card are stored in a concealed or unconcealed form, and wherein the access to concealed data items is allowed once user identification is positively verified by means of the smart card functionality. The secure processor may further comprise PKI functionality and hash (or MAC) module, said hash (or MAC) module is employed for carrying out data integrity tests. The PKI functionality and/or hash module may be implemented by firmware or hardware, or by a combination thereof.

According to one aspect the present invention is directed to a handheld portable storage device comprising a nonvolatile memory (e.g., flash memory), data communication connectivity means (e.g., a USB connector, a serial/parallel UART connector and/or a smartcard connector) , and secure processor means comprising: processing means, memory, interfacing means capable of interfacing between the secure processor and a data processing system over the data communication connectivity means and between the secure processor and the nonvolatile memory, a secure operating system, user identification data (secret data e.g., passwords and cryptographic keys) stored in the secure memory, file management information and other data and executable code stored in the nonvolatile memory. Advantageously, the secure processor may further comprise a PKI module, encryption/decryption means, and/or hash or MAC module implemented in the secure processor by hardware or firmware, or a combination thereof. Preferably, the secure operating system is a smart card operating system complying with the ISO 7816 specification standard, or a modified version thereof.

The handheld portable storage device may further comprise digital signatures stored in the memory of the secure processing means, wherein the digital signatures are associated with data items stored in the nonvolatile memory. Additionally, the handheld portable storage device may further comprise security detector (s) capable of detecting hardware attacks .

Alternatively, the data communication connectivity means may be implemented by a type of wireless communication means, such as, but not limited to, Bluetooth, RFID, WiFi, IrDA, and the like. Accordingly, if the storage device is equipped with such wireless data communication means the data processing system preferably also include corresponding wireless data communication means suitable for wirelessly communicating with the storage device. In another aspect the present invention is directed to a method for securely handling data with a data processing system capable of storing or accessing data in an external nonvolatile memory, the method comprising:

Providing an external handheld portable storage device comprising said nonvolatile memory (e.g., flash memory), data communication connectivity means (e.g., serial/parallel UART PC port, USB port, and/or smart card port) , a secure processor comprising a cpu, a secure memory, PKI means, encryption/decryption means, and interfacing means suitable for interfacing between said secure processor and said data processing system over said data communication connectivity means and between said secure processor and said nonvolatile memory, wherein said secure memory comprises a secured operating system (e.g., smart card operating system), user identification data such as passwords and/or cryptographic keys, file management information, and other data or executable code needed for the device operation;

Once establishing a data communication link between said storage device and said data processing system by means of its data communication connectivity means reading and executing by said secure processor instructions of said secure operating system, or other executable code stored in said secure memory;

Whenever needed allowing access to non-privileged data items stored in said nonvolatile memory via said data processing system;

Whenever privileged data needs to be stored or read, performing a user authentication procedure such as provided in said secure operating system, and upon positive user authentication :

- whenever storing a privileged data item in said nonvolatile memory receiving said privileged data item via said data communication link, encrypting said privileged data item by said secure processor, and storing the encrypted item in said nonvolatile memory; and

- whenever retrieving a privileged data item, reading said privileged data item from said nonvolatile memory, decrypting it, and transferring the decrypted item by said secure processor to said data processing system over said data communication link.

The method may further comprise providing said storage device hash (or MAC) capabilities for verifying the integrity of the stored data items, by performing the following steps: generating a digital signature for each data item stored in said nonvolatile memory and storing said digital signatures in said secure memory; and whenever the integrity of a stored data item is to be checked, generating a digital signature for said data item and verifying that said digital signature and the corresponding digital signature stored in said secure memory are identical.

Optionally, the access to both privileged and non-privileged data items may require user authentication. The method may further comprise establishing a secure channel between the storage device and the data processing system for accessing the privileged data items stored in the storage device.

According to yet another aspect the present invention is directed to a system comprising: a handheld portable storage device according to any one of embodiments described hereinabove or hereinbelow, a computerized system comprising data communication connectivity means suitable for establishing a data communication link with said storage device and a secure module capable of carrying user authentication as specified by the secure operating system provided in said handheld portable storage device. Advantageously, the security module may be further adapted to establish a secure link with the storage device over the data communication link, wherein the secure link is used for securely accessing privileged data items stored in the storage device .

Brief Description of the Drawings

The present invention is illustrated by way of example in the accompanying drawings, in which similar references consistently indicate similar elements and in which:

Fig. 1 is a block diagram illustrating a preferred embodiment of the storage device of the invention; and Fig. 2 is a block diagram illustrating a specific embodiment employing USB and smart card connectivity; Fig. 3 is a flowchart demonstrating a preferred data write flow scheme in the storage device of the invention; and

Fig. 4 is a flowchart demonstrating a preferred data read flow scheme in the storage device of the invention.

It is noted that the embodiments exemplified in the figures are not intended to be in scale and are in diagram form to facilitate ease of understanding and description. Detailed Description of Preferred Embodiments

The present invention provides a secure handheld portable storage device having relatively large memory capacity which behaves and performs like a conventional smart-card but with increased processing capabilities and memory capacity. In general, the storage device of the invention comprises a nonvolatile memory, data communication connectivity means, a secure processor operated with a smart card operating system, wherein the secure processor comprises a cpu, a secure memory, PKI and encryption/decryption means, and interfacing means for interfacing between the secure processor and a data processing system over the data communication connectivity means and between the secure processor and the nonvolatile memory.

Typically, smartcard devices provide storage memory of about 64 kilo bytes (64 KB) to 1 mega bytes (1 MB), and data communication rates of a bout 9.6 KB/sec to 300 KB/sec. Therefore typical smartcard devices have limited implementations and they are not suitable for applications requiring storage of documents and/or images, and/or applications requiring data processing and communication of such documents and/or images. On the other hand, typical smart card devices provide attractive functionality and features which are widely accepted nowadays as a standard in banking, healthcare, security, and other implementations requiring personal identification and secure handling of confidential and secret information.

The storage device of the invention provides a smart-card-like device which overcomes the memory capacity, processor performance, and communication rate, limitations of conventional smart card chips, and which does not require a smart card reader. Specific designs of the storage device of the invention may be adapted to provide nonvolatile memory- storage of about 16 to 64 GB, and data communication rates of a bout 60 MB/sec. The memory capacity of the storage device of the invention may be however adapted per design according to specific application needs, such that it may be constructed to comprise a smaller memory, if so needed (e.g., of few MBs) .

In a specific preferred embodiment of the invention there is provided a secure storage device having USB connectivity and a nonvolatile memory optionally providing a large amount of storage capacity, said secure storage device having embedded secure processing capabilities for cryptographic functions and optional additional (security and other) firmware applications, by using embedded smart card operating system (SCOS), with no need for using smart card chip. The device may also include standard, non-secure, large memory components (e.g., Flash memory) . The data stored in those unsecured memory components may be accessed only via the secure processor, which can encrypt it and which can also securely store the encryption keys and secret data inside the secure memory, such that the data stored in the large memory component becomes protected. On a similar level to the data stored in a smart card, but without the need for a smart card chip .

Accordingly, by using an embedded such a smart card operating system (SCOS) complying with the ISO 7816 specification standard in the storage device of the invention, there is no need in using a smartcard chip for implementing the smart card functionality needed for the device security. Fig. 1 is a block diagram illustrating a preferred embodiment of a storage device 10 of the invention. In general, storage device 10 comprises a secure processor 16 configured to handle and store secure data, such as passwords and cryptographic keys 13a, in an internal secure memory unit 13, and perform cryptographic tasks, such as digital signature and data encryption/decryption, by means of cpu 19, PKI unit 12, and encrypt/decrypt unit 4. Processor 16 is further adapted to communicate with external computerized units via communication port 11 by means of communication interface 14a, and with an onboard nonvolatile memory 18 by means of external memory interface 14b.

Secure memory 13 is an internal memory provided integrally in secure processor 16, and it is used for storing secret data 13a, such as passwords and cryptographic keys, a secure operating system (OS) 13c, file management information 13d, and optionally (indicated by a dashed line) data items signatures 13b, as will be explained hereinbelow.

Secure processor 16 is preferably implemented by a secure and preferably fast chip processor integrally comprising internal secure memory 13, PKI unit 12, an optional (indicated by a dashed line) hash (or MAC) unit 15, security detector (s) 17 for detecting and preventing hardware attacks, communication interfacing means 14a (e.g., complying with the USB protocol specification) and external memory interfacing means 14b. Nonvolatile memory unit 18 is preferably a type of flash memory, such as but not limited to Samsung NAND flash, having memory capacity of about 16GB to 64 GB, or greater (according to developments in the memory devices industry) . Communication port 11 comprises the connectivity means capable of providing access to the storage device 10 and the power supply needed for its functionality, otherwise, an internal power source (not shown) may be further embedded in the device. Most preferably, communication port 11 is adapted to comply with the USB protocol specification i.e., using USB connector.

The operating system 13c stored in secure memory 13 is used by processor 16 for managing the data stored in storage device 10, for handling the security and cryptographic tasks, and for communicating with external devices over the a communication data link. In a preferred embodiment of the invention operating system 13c is a smart card operating system (COS) complying with the ISO 7816 standard, such that storage device 10 behaves and appears to external data processing systems connected to it as a regular smart card.

File management information 13d comprises properties of stored data items, such as for example, file types, access permissions, indications concerning encryption, or other protection, if used. This information is preferably stored and managed by means of the standard file management schemes used in smart cards.

This implementation of the storage device is particularly advantageous since it provides a device having all smart card functionalities and protections which may be used in smart card applications, such as banking applications and any application requiring smart card personal identification, but with improved processing power and substantially increased memory capacity and data communication rates.

The data stored in nonvolatile memory unit 18 may be concealed or unconcealed. The concealed data is preferably stored in an encrypted form in order to restrict access thereof only to authorized users. As will be now described in details, stored data items are concealed in nonvolatile memory 18 by encrypting them by means of processor 16. A digital signature 13b of the stored concealed data may optionally (indicated by a dashed line) be generated and stored in the secure memory 13 for future validity tests.

Storage device 10 may be implemented utilizing any suitable read/write nonvolatile memory device to be used as its nonvolatile memory 18, such as but not limited to a flash memory as manufactured by Samsung (NAND Flash memory) . Secure processor 16 may be implemented by a type of secure processor such as but not limited to a type of ARM7 processor.

Fig. 2 is a block diagram illustrating a specific embodiment 10a employing USB connectivity 11a and smart card connectivity lib, such that device 10a can be accessed via the USB connector 11a or via the smart card connector lib provided therein. By way of example, storage device 10a may be connected to a data processing system 20 (e.g., personal computer - PC) , by means of standard USB connector and interfacing means 20a provided in data processing system 20. Once data communication link 20c is established between storage device 10a and data processing system 20 application programs 2Op running in data processing system 20 may access data items stored the nonvolatile memory 18 provide in storage device 10a.

Nonvolatile memory 18 may comprise secured data items 18s (also referred to herein as privileged data items) stored therein in an encrypted form, and non-secured data items 18n (also referred to herein as non-privileged data items) stored therein in a non-concealed form. Accordingly, application programs 2Op in data processing system 20 may fetch secured and non-secured data items, 18s and 18n, directly (indicated by solid straight arrowed line 20k) through data communication link 20c. While the non-secured data items 18n can be read and processed by application programs 2Op by such direct access attempts, since they are stored in a non-concealed form, any attempt to process secured data items 18s in such direct accesses will result in obtaining data stored in a concealed form, which is non-readable by application programs 2Op, since the data in the secured data items 18s is encrypted. In order to provide authorized users access to the secure data items 18s a security module 20m may be provided in data processing system 20, wherein security module 20m is adapted to carry out the user authentication procedure required by the secure operating system. The security criteria implemented in the storage device 10a may require transmission of privileged data over a secure channel, and in this case security module 20m is further adapted to establishing a secure channel (e.g., SSL, diffie-helman) with the storage device over communication link 20c and thereafter for communicating the privileged data thereover.

According to one specific embodiment of the invention the access to both secure and non-secure data items stored in the storage device may require user authentication. For example, the nonvolatile memory of the storage device may be partitioned such that certain, or all of the, memory partitions can be access only by authenticated user(s) .

Fig. 3 is a flowchart illustrating a preferred data write flow scheme employed in the storage device (10) of the invention. The write operation is initiated in step 30, wherein write request is issued by the data processing system connected to the storage device. In step 31 the validity of the write request is checked and user authentication process is performed. According to one specific preferred embodiment of the invention, the access to non-privileged data items (e.g., 18n in Fig. 2) stored in the nonvolatile memory via the data processing system is permitted (not shown) , whenever needed, while the access to privileged data items (18s in Fig. 2) stored in the storage device (10 or 10a) is permitted after positively passing the user authentication in step 31, typically by comparing a user password provided via the external data processing system to a user password stored in secure memory (13) . If a mismatch is determined in step 32, the access to the storage device is denied as the control is passed to block 33.

If access to privileged data items is permitted in step 32, the process proceeds in block 34 wherein encryption key is generated by the secure processor (16) and stored in the secure memory (18) . Step 34 is however optional since it is not necessary to generate a new encryption key to each data item to be stored in the nonvolatile memory of the device, namely, a previously generated encryption key may be used.

In step 35 the secure processor (16) in the storage device receives the data to be stored over the data communication link (20c in Fig. 2) and encrypts the received data, and then in step 37 stores the encrypted data in the nonvolatile memory (18) . If data integrity tests are desired, step 35 is followed by optional (indicated by a dashed line) step 36 wherein the processor generates a signature of the encrypted data item, and in this case after storing the encrypted data in step 37, in optional step 38 the signature is stored in the secure memory of the device. Fig. 4 is a flowchart illustrating a preferred data read flow scheme which may be employed in the storage device (10) of the invention. Read operation is initiated in step 40 whenever a read request is received from the data processing system. In step 41 the validity of the read request is checked and user authentication process is performed. According to one specific preferred embodiment of the invention the access to non- privileged data items (18n) stored in the nonvolatile memory via the data processing system is permitted (not shown) without requiring authentication, and for accessing privileged data items (18s) it is permitted only after positively passing the user authentication in step 41. If read access is denied in step 42 the process is terminated in step 43.

If read access is permitted in step 42, in step 44 the requested data item is read from the nonvolatile memory (18) and the respective decryption key is generated instantly or read from the secure memory, and in step 48 the secure data item is decrypted by the processor (16) . In step 49 the decrypted data is transferred to the computerized data processing system over the data communication link. If optional (indicated by a dashed line) data integrity test is needed, the control is passed from block 44 to step 45, wherein the processor generates a digital signature of the requested data item stored in the nonvolatile memory, and in step 46 compares it to the corresponding signature stored in the secure memory (18) . If it is determined in the validity check performed in step 47 that the signatures are identical i.e., data was not tampered with, the control is passed to step 48 wherein the requested data item is decrypted and thereafter, in step 49, the decrypted data is transferred to the data processing system over the data communication link (20c) . If signatures mismatch is determined in the validity test of step 47, in step 50 an alert is issued for indicating that the data item stored in the nonvolatile memory has been tampered with.

The data flows shown in Figs. 3 and 4 may be easily modified to allow encrypted data to be written and read form the data processing system. In this way privileged data may be stored external to the storage device, such that whenever this data is needed it may be accessed by decrypting it by means of secure processor and cryptographic keys of the storage device after positive user identification. Furthermore, the data transfer between storage device and the external data processing system may be transferred over a secured channel (e.g., Public-key cryptography) by employing the smart card functionality of the storage device.

According to another specific preferred embodiment of the invention any access to the non-volatile memory is permitted only after positively authenticating the user. Namely, in such specific preferred embodiment the access to both secure and non-secure data items requires user authentication. Accordingly, any attempt to access the non-volatile memory for writing secure or non-secure data items also requires authenticating the user first.

While the storage device of the present invention may be implemented in various different ways (e.g., secured disks), it is preferably implemented as a personal handheld portable storage card (e.g., having credit-card dimensions) allowing users to securely store and quickly process substantially big data files. Of course, the data may be stored in the storage device in a compressed and encrypted format. This implementation substantially augments the range of applications and usages of the secure data storage device of the invention. For example, in a particular embodiment of the invention the storage device of the invention is used as user card in healthcare services, allowing to securely store all the healthcare data records (e.g., patient history, x-ray, MRI, CT scans, etc.) on the users' personal storage cards, while benefiting the conventional smart cad security and identification capabilities.

Furthermore, the storage device of the invention may be modified to allow it to wirelessly communicate (e.g., Bluetooth, RFID, WiFi, IrDA, and the like) with the data processing system. This wireless communication may be provided in addition to, or instead of, the data communication connectivity of the device. Such modifications are within the skills of data communication engineers.

The above examples and description have of course been provided only for the purpose of illustration, and are not intended to limit the invention in any way. As will be appreciated by the skilled person, the invention can be carried out in a great variety of ways, employing more than one technique from those described above, all without exceeding the scope of the invention.

Claims

1. A handheld portable storage device comprising a nonvolatile memory, data communication connectivity means, and secure processor means comprising: processing means, memory, interfacing means capable of interfacing between said secure processor over said data communication connectivity means and with said nonvolatile memory, a secure operating system, user identification data stored in the secure memory, file management information and other data and/or executable code.

2. The handheld portable storage device according to claim 1, wherein the secure processor further comprises a PKI module.

3. The handheld portable storage device according to claim 1, wherein the secure processor further comprises encryption/decryption means.

4. The handheld portable storage device according to claims 1, 2 and 3, wherein the secure operating system is a smart card operating system complying with the ISO 7816 specification standard, or a modified version thereof.

5. The handheld portable storage device according to claims 1, 2 and 3, wherein the user identification data comprise passwords and cryptographic keys.

6. The handheld portable storage device according to claims 1, 2 and 3, further comprising a hash or MAC module implemented in the secure processor by hardware or firmware, or a combination thereof.

7. The handheld portable storage device according to claim 6 further comprising digital signatures stored in the memory of the secure processing means, wherein said digital signatures are associated with data items stored in the nonvolatile memory.

8. The handheld portable storage device according to claims 4, 5 or 7 implemented in a form of a storage card having geometrical dimensions of a credit card.

9. The handheld portable storage device according to claim 1 or 8 wherein the data communication connectivity comprises, a USB connector, a serial/parallel UART connector, a smartcard connector, and/or wireless communication means.

10. The handheld portable storage device according to claim 1 or 9 wherein the nonvolatile memory is a type of a flash memory .

11. A method for securely handling data in a data processing system employing the handheld portable storage device according to any one of claims 1 to 10, the method comprising:

Establishing a data communication link between said storage device and said data processing system;

Reading and executing by the secure processor instructions of the secure operating system, and/or other executable code stored in the secure memory;

Whenever privileged data needs to be stored or read, performing a user authentication procedure such as provided in said secure operating system, and upon positive user authentication : * whenever storing a privileged data item in said nonvolatile memory receiving said privileged data item via said data communication link, encrypting said privileged data item by said secure processor, and storing the encrypted item in said nonvolatile memory; and

* whenever retrieving a privileged data item, reading said privileged data item from said nonvolatile memory, decrypting it, and transferring the decrypted item to said data processing system over said data communication link.

12. The method according to claim 11 further comprising: generating a digital signature for each data item stored in the nonvolatile memory; storing said digital signatures in the secure memory; and whenever the integrity of a stored data item is to be checked, generating a digital signature for said data item and verifying that said digital signature and the corresponding digital signature stored in said secure memory are identical.

13. The method according to claim 11 further comprising establishing a secure channel between the storage device and the data processing system, wherein said secure channel is used for accessing privileged data items stored in the storage device .

14. The method according to claim 11 further comprising generating a cryptographic key whenever storing a secured data item.

15. A comprising: a storage device according to any one of claims 1 to 10, a computerized system comprising data communication connectivity means suitable for establishing a data communication link with said storage device and a secure module capable of carrying user authentication as specified in the secure operating system provided in said storage device.

16. The system according to claim 15 wherein the security module is further adapted to establish a secure link with the storage device over the data communication link.