Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
  • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
  • H04L9/3247—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving digital signatures
  • H04L9/3249—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving digital signatures using RSA or related signature schemes, e.g. Rabin scheme
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
  • H04L9/30—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
  • H04L9/3006—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy underlying computational problems or public-key parameters
  • H04L9/302—Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy underlying computational problems or public-key parameters involving the integer factorization problem, e.g. RSA or quadratic sieve [QS] schemes
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
  • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
  • H04L9/3234—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token

Definitions

• the invention relates to a method for the secure distribution of data and / or programs according to the preamble of claim 1.
• Methods for distributing software SW from an issuing point to a large number of terminals of the same type or to chip cards are used more and more in particular due to the possibilities of remote data transmission.
• the issuing body generates an electronic signature of the software SW using a public key procedure to ensure the authenticity of the software SW.
• the issuing body uses a generally known method to calculate a certificate M of the software SW to be signed, which, in addition to other data, contains above all a hash value H (SW) which is dependent on the software.
• H (SW) is a publicly known hash method.
• the issuing agency encrypts the certificate M with its private key D. The result of this encryption is the electronic signature S.
• the terminal or the chip card calculates the hash value H (SW) of the software SW and checks whether H (SW) is correctly entered in the certificate M. If this is the case, the receiving agency accepts the software SW, otherwise it rejects the software SW.
• the best known public key procedure for the generation of electronic signatures is the RSA procedure.
• a variant of the RSA method is the Rabin method or a variant of the Rabin method according to Williams.
• the issuing agency calculates the signature
• the receiving agency can verify the signature by
• the security of the Rabin method resides in that taking the square root of a number modulo a prime (if one exists) is easy, while taking the square root of a random number modulo a composite number is at least as difficult to factorize that composite number .
• the issuing body To sign a message M, the issuing body first checks which of the four values M, N-M, N / 2 or N-N / 2 is the quadratic remainder mod P and mod Q. This can be done effectively by calculating the Jacobi symbols (N / P) and (M / Q):
• Terminal B first calculates the value
• M 4 mod 8
• Modular multiplication is required to verify a signature on the chip card or Terminal B; i.e. the receiving agency calculates:
• Montgomery a method according to Montgomery is used for the verification of the electronic signature.
• L is the basis on which the long number arithmetic is performed.
• L 2 8 is used for an 8-bit processor
• L 2 16 for a 16-bit processor, etc.
• the value i must be at least so large that the condition is satisfied.
• the modular exponentiation is thus traced back to a sequence of squarings and multiplications with the basis A (mod N).
• A0 A 1 * L 1 can easily be calculated by repeatedly squaring and multiplying by AO, the value A E * L 1 .
• a further Montgomery multiplication of the intermediate result A E * L 1 by 1 supplies the desired final result A E.
• the signature check When downloading software to a terminal or a chip card, the signature check must be carried out there. Since the terminal generally has little computing power, the signature check must be carried out as simply as possible.
• signature S is transferred to Terminal B.
• Terminal B calculates:
• the following modification is therefore carried out, which compared to the conventional method is a Montgomery multiplication and the storage of the value - 8th -
• the signature check therefore only requires a Montgomery multiplication on the terminal.

Landscapes

• Engineering & Computer Science (AREA)
• Computer Security & Cryptography (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Computing Systems (AREA)
• Theoretical Computer Science (AREA)
• Storage Device Security (AREA)
• Stored Programmes (AREA)
• Information Transfer Between Computers (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7867089

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (18)

Citations (2)

Family Cites Families (14)

• 1998
  • 1998-05-08 DE DE19820605A patent/DE19820605A1/de not_active Withdrawn
• 1999
  • 1999-04-19 AT AT99920709T patent/ATE305683T1/de not_active IP Right Cessation
  • 1999-04-19 WO PCT/EP1999/002630 patent/WO1999059287A1/de not_active Ceased
  • 1999-04-19 DE DE59912605T patent/DE59912605D1/de not_active Expired - Lifetime
  • 1999-04-19 JP JP2000548992A patent/JP4708565B2/ja not_active Expired - Lifetime
  • 1999-04-19 EP EP99920709A patent/EP1080559B1/de not_active Expired - Lifetime
  • 1999-04-19 US US09/673,657 patent/US6405923B1/en not_active Expired - Lifetime

Patent Citations (2)

Non-Patent Citations (1)

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