摘要:
Methods and apparatus are provided for authenticating communications between a user computer and a server via a data communications network. A security device has memory containing security data, and security logic to use the security data to generate an authentication response to an authentication message received from the server in use. An interface device communicates with the security device. The interface device has a receiver for receiving from the user computer an authentication output containing the authentication message sent by the server to the user computer in use, and interface logic adapted to extract the authentication message from the authentication output and to send the authentication message to the security device. Includes a communications interface for connecting to the server via a communications channel bypassing the user computer. Either the security device or interface device sends the authentication response to the server via the communications channel bypassing the user computer.
摘要:
The invention is directed to a method for a software provider to enable a software-acquiring entity to arrive from an existent first signed piece of code at a second signed piece of code. Both pieces of code were generated at the software provider by use of a first software archive generator under use of generation instructions. The software provider provides to the software-acquiring entity a difference code that comprises the steps necessary to arrive from the first signed piece of code at the second signed piece of code. The difference code is combinable at the software-acquiring entity with the first signed piece of code by a second software archive generator to generate the second signed piece of code. The second software archive generator is therefor to be fed with those generation instructions that were used by the first software archive generator for the generation of both pieces of code.
摘要:
A space-efficient and flexible mechanism for implementing a virtual machine in a resource-constrained environment such as a smartcard is proposed. The virtual machine is designed for interpreting or carrying out instructions which are identified by an instruction code, also called opcode. Both, the addresses, respectively identifiers, of the functions implementing the instruction codes, respectively opcodes, which the virtual machine interprets, as well as parameters to those functions are kept within lookup tables.
摘要:
Provides a data processing system comprising a processor and encrypted information in a first persistent memory whose level of information leakage is higher than that of a second persistent memory. The second persistent memory stores a cryptographic key for decrypting the encrypted information, generating therefrom unencrypted information that is usable by the processor for executing an operation. The cryptographic key may be used for encrypting the unencrypted information, generating the encrypted information. Also provided is a method of processing such a data-processing system with an operating system, comprising writing unencrypted information into the first persistent memory, encrypting the unencrypted information under use of the first cryptographic key, creating therefrom encrypted information in the first persistent memory, and setting the data-processing system to a state in which writing into the first persistent memory is controlled by the operating system.
摘要:
The invention is directed to a method for a software provider to enable a software-acquiring entity to arrive from an existent first signed piece of code at a second signed piece of code. Both pieces of code were generated at the software provider by use of a first software archive generator under use of generation instructions. The software provider provides to the software-acquiring entity a difference code that comprises the steps necessary to arrive from the first signed piece of code at the second signed piece of code. The difference code is combinable at the software-acquiring entity with the first signed piece of code by a second software archive generator to generate the second signed piece of code. The second software archive generator is therefor to be fed with those generation instructions that were used by the first software archive generator for the generation of both pieces of code.
摘要:
A method for creating an object in a non-persistent memory is proposed. From an instruction code sequence, a first instruction code is read out which effects the execution of a first function which effects the choice of a non-persistent memory as the location for the next object to be created. This object creation is effected by the execution of a second function which is effected by reading out a second instruction code. Furthermore it is proposed to store a pointer to a transient object in the stack memory and to provide a mechanism for writing this pointer to and reading it from a persistent memory.
摘要:
A method for transactional writing of data into a data space in a persistent memory. The data space has a data space header which signals that the data space is free. A data header is generated when there is a writing transaction in the data space. After successful completion of the transactional writing, the data header signals that the data space is occupied by the written data. The data is written directly to the persistent memory, and in the case the transactional writing is not successfully completed, the data space header is valid for the data space. If the transactional writing is successfully completed, the data header is valid for the written data in the data space. A persistent buffer serves for storing validity information for ensuring the validity of the data header or the data space header as appropriate.
摘要:
The invention is directed to a method for a software provider to enable a software-acquiring entity to arrive from an existent first signed piece of code at a second signed piece of code. Both pieces of code were generated at the software provider by use of a first software archive generator under use of generation instructions. The software provider provides to the software-acquiring entity a difference code that comprises the steps necessary to arrive from the first signed piece of code at the second signed piece of code. The difference code is combinable at the software-acquiring entity with the first signed piece of code by a second software archive generator to generate the second signed piece of code. The second software archive generator is therefor to be fed with those generation instructions that were used by the first software archive generator for the generation of both pieces of code.
摘要:
Scheme for the distinguishing of reachable objects and non-reachable objects used by an object-based application in a system with volatile memory of limited size. The object-based application operates on n objects whereby Z objects thereof are root objects. The following steps are carried out for each root object: (a) traversing from said root object to any other object that can be reached from said root object; (b) marking all objects that were reached from said root object and storing, while marking, in said volatile memory a description of the path from said root object to the currently visited object; if the marking phase reaches an object and the respective path does not fit into said volatile memory, then this object is not marked but identified as an object which has to be processed later; and continuing the marking phase until all root objects identified as objects which have to be processed later are processed.
摘要:
A technique for language verification of a Java® card CAP file is provided. The Java® card CAP file is converted from an original Java® code file while conserving its original Java® semantics. The Java® card CAP file is converted into a corresponding converted Java® code file that is semantically identical to the Java® card CAP file. In a language-verification step, the converted Java® code file is then verified if it has been found to comply with a predetermined language specification.