摘要:
The present invention provides for authenticating a message. A security function is performed upon the message. The message is sent to a target. The output of the security function is sent to the target. At least one publicly known constant is sent to the target. The received message is authenticated as a function of at least a shared key, the received publicly known constants, the security function, the received message, and the output of the security function. If the output of the security function received by the target is the same as the output generated as a function of at least the received message, the received publicly known constants, the security function, and the shared key, neither the message nor the constants have been altered.
摘要:
A method and system for encrypting and verifying the integrity of a message using a three-phase encryption process is provided. A source having a secret master key that is shared with a target receives the message and generates a random number. The source then generates: a first set of intermediate values from the message and the random number; a second set of intermediate values from the first set of values; and a cipher text from the second set of values. At the three phases, the values are generated using the encryption function of a block cipher encryption/decryption algorithm. The random number and the cipher text are transmitted to the target, which decrypts the cipher text by reversing the encryption process. The target verifies the integrity of the message by comparing the received random number with the random number extracted from the decrypted cipher text.
摘要:
A system for secure communication. A random value generator is configured to generate a random value. A message validation code generator is coupled to the random value generator and configured to generate a message validation code based on a predetermined key, a message, and the random value. A one-time pad generator is coupled to the random number generator and configured to generate a one-time pad based on the random value and the predetermined key. And a masked message generator is coupled to the one-time pad generator and configured to generate a masked message based on the one-time pad and the message. In a particular aspect, a protected message envelope generator is coupled to the random value generator, the message validation code generator, and the masked message generator, and is configured to generate a protected message envelope based on the random value, the message validation code, and the masked message. In another aspect, a protected message envelope reader is configured to receive a protected message envelope and generate a random value, a masked message, and a first message validation code based on the received protected message envelope. A one-time pad generator is coupled to the protected message envelope reader and is configured to generate a one-time pad based on the random value and a predetermined key. A message unmasker is coupled to the one-time pad generator and protected message envelope reader, and is configured to generate an unmasked message based on the one-time pad and the masked message.
摘要:
A system for secure communication is provided. A random value generator is configured to generate a random value. A message validation code generator is coupled to the random value generator and configured to generate a message validation code based on a predetermined key, a message, and the random value. A one-time pad generator is coupled to the random number generator and configured to generate a one-time pad based on the random value and the predetermined key. And a masked message generator is coupled to the one-time pad generator and configured to generate a masked message based on the one-time pad and the message. A protected message envelope generator is coupled to the random value generator, the message validation code generator, and the masked message generator, and is configured to generate a protected message envelope based on the random value, the message validation code, and the masked message.
摘要:
A method, an apparatus, and a computer program are provided for efficiently determining an inverse multiplicative modulo. In many public-key cryptographic algorithms, an inverse modulo is usually calculated in key generation. However, because many Reduced Instruction Set Computers (RISCs) do not have the hardware support for division, good results are often not yielded. Therefore, to efficiently calculate a inverse modulo, an modified algorithm that utilizes a minimum of 3 division and 2 multiplications in conjunction with shifts and addition/subtractions is employed. The modified algorithm then is able to efficiently utilize the properties of the RISC processors to yield good results, especially when developing keys for public-key cryptographic algorithms.
摘要:
The present invention provides for authenticating a message, A security function is performed upon the message, The message is sent to a target. The output of the security function is sent to the target. At least one publicly known constant is sent to the target. The received message is authenticated as a function of at least a shared key, the received publicly known constants, the security function, the received message, and the output of the security function. If the output of the security function received by the target is the same as the output generated as a function of at least the received message, the received publicly known constants, the security function, and the shared key, neither the message nor the constants have been altered.
摘要:
A technique for tracking one or more thresholds relating to the blocking of a particular screen name used on an IM system is disclosed. If the number of people who have blocked a particular screen name reaches a threshold amount, a determination is made that the screen name is being used by a spimmer or other bothersome person, and disciplinary action can be taken. In a preferred embodiment, the email address associated with a user name of a suspected spimmer is identified and all screen names associated with that email address are also subjected to disciplinary action, if desired. Thus, an IM company can suspend all screen names of a spimmer that are tied to the same email address, even though not all (or even none) of the screen names individually have reached a threshold level for discipline/suspension.
摘要:
The present invention provides for authenticating a message. A security function is performed upon the message. The message is sent to a target. The output of the security function is sent to the target. At least one publicly known constant is sent to the target. The received message is authenticated as a function of at least a shared key, the received publicly known constants, the security function, the received message, and the output of the security function. If the output of the security function received by the target is the same as the output generated as a function of at least the received message, the received publicly known constants, the security function, and the shared key, neither the message nor the constants have been altered.
摘要:
A system to exchange and authenticate public cryptographic keys between parties that share a common but secret password, using a pair of random numbers, a pair of Diffie-Hellman public keys computed from the random numbers and the password, a Diffie-Hellman symmetric secret key computed from the Diffie-Hellman public keys and the random numbers, and hashed values of arguments that depend upon these elements.
摘要:
A time stamping protocol has two stages referred to as the ticketing stage and the certification stage. During the ticketing stage, the document or other identifying data is sent to the TSA. The TSA generates a “ticket” based on the document or other identifying data and a time indication derived from a trusted clock. The ticket, which serves as an unsigned time stamp receipt, is transmitted back to the document originator. During the certification stage, the holder of the ticket requests a certified time stamp receipt by presenting the ticket to the TSA. The TSA verifies the ticket and generates a signed time stamp receipt, called the ticket stub, which is then transmitted back to the document originator. The ticket stub serves as a “universal time-stamp” that the holder of the ticket stub can use to prove the date of the document.