摘要:
A system and method of creating and managing encryption keys in a data processing device generates subsequent encryption keys by combining the existing encryption key with an existing password and seed value. In the preferred embodiment, the initial encryption key is embedded during manufacture and is unknown to the user and manufacturer, thus ensuring that all subsequent encryption keys are derived from an unknown value. When a subsequent encryption key is generated, all data encrypted using the existing encryption key is decrypted using the existing encryption key and re-encrypted using the subsequent encryption key before the existing encryption key is overwritten. In a further aspect, during encryption/decryption the encryption key is combined with the sector address of the data to be encrypted/decrypted in order to generate a unique key for each sector of data to be encrypted/decrypted.
摘要:
The present invention provides a secure JTAG interface to an application-specific integrated circuit (ASIC). In the preferred embodiment the invention operates through the combined efforts of a Security Module (SM) comprising a state machine that controls the security modes for the ASIC, and a Test Control Module (TCM) which contains the JTAG interface. The TCM operates in either a restricted mode or an unrestricted mode, depending on the state of the SM state machine. In a restricted mode, only limited access to memory content is permitted. In an unrestricted mode, full access to memory content is permitted.
摘要:
A method and device for authenticating software stored in non-volatile memory in a data processing device. The processor comprises an internal immutable memory, preferably a read only memory (ROM), and during the boot up procedure the software in external memory is authenticated using code that is stored in the internal ROM. The on-chip ROM is physically integrated with the processor itself, so the code stored in ROM can neither be tampered with nor replaced, and can therefore be assumed at all times to be authentic. Thus, in the method and device of the invention known good code is used to authenticate the untrusted code in external memory, so the integrity of the system is significantly improved.
摘要:
During generation of a signature on a message to create a signed message, a signer determines one of the signature components such that particular information can be extracted from the signature component. The particular information may be related to one or more of the signer and the message to be signed. After receiving a signed message purported to be signed by the signer, a verifier can extract the particular information from the signature component.
摘要:
A smart card reader receives an Answer to Reset (ATR) from a smart card and transmits the ATR over a communication link to a computing device without waiting for an ATR request from the computing device. The computing device may cache the ATR and use it for subsequent communication sessions with the smart card.
摘要:
Various embodiments are described for providing password approval on a device. The password approval includes getting the user password, generating at least one symbolically equivalent password and then comparing the at least one symbolically equivalent password with at least one specified forbidden password. The user password is disapproved if one of the symbolically equivalent passwords corresponds to the at least one forbidden password.
摘要:
A certificate from a smart card is imported into a computerized device via a smart card reader. The computerized device calculates a hash of the imported certificate and stores the hash in memory. The hash may be stored in a region of the memory that is unaffected by upgrades to the device.
摘要:
A system and method for processing certificates located in a certificate search. Certificates located in a certificate search are processed at a data server (e.g. a mobile data server) coupled to a computing device (e.g. a mobile device) to determine status data that can be used to indicate the status of those certificates to a user of the computing device, without having to download those certificates to the computing device in their entirety. The data server is further adapted to transmit the status data to the computing device. In one embodiment, at least one status property of the certificates is verified at the data server in determining the status data. In another embodiment, additional certificate data is determined and transmitted to the computing device, which can be used by the computing device to verify, at the computing device, at least one other status property of the certificates.
摘要:
A handheld data processing device includes stored data that is intended to be kept secure from unauthorized access. The handheld data processing device includes applications that store such secure data and which make use of plain text data corresponding to the secure data. An identifier is defined to be associated with defined plain text data. When the handheld data processing device is placed in a locked or secure state, code executable on the device is able to search for plain text identifiers. Code executable on the device is consequently able to display to the user whether plain text data is stored on the device or not.
摘要:
Increasing security for a hand-held data processing device with communication functionality where such a device includes an access-ordered memory cache relating to communications carried out by the device. The hand-held data processing device has a locked state that is entered by the device receiving or initiating a trigger. On occurrence of the trigger to enter the locked state the memory cache is reordered so as to disrupt the access-ordering of the cache to obscure device traffic information and thus increase the security of the device in the locked state.