On the Security of EPOC and TSH-ESIGN
نویسندگان
چکیده
We submitted a public-key encryption scheme, EPOC, and digital signature scheme, TSH-ESIGN, to IEEE P1363a. The security of EPOC and TSH-ESIGN is based on the intractability of factoring n = pq, where p and q are primes. TSH-ESIGN is also based on the intractability of the approximate e-th root (AERP) assumption, which is the approximate version of the RSA assumption. This draft describes the latest research status on the intractability of factoring n = pq and the approximate e-th root assumption, and concludes that these problems are considered to be almost as intractable as those of factoring n = pq and of inverting the RSA function (i.e., solving the e-th root). 1 Security of EPOC and TSH-ESIGN 1.1 Security of EPOC EPOC (EPOC-2 with one-time padding) [9] is proven to be secure in the strongest sense (nonmalleable against chosen ciphertext attacks: NM-CCA2) under the random oracle model and the factoring assumption of n = p2q. That is, EPOC is as secure as factoring n = p2q (in the strongest sense in the random oracle model). Schemes Security Number-theoretical Random function against CCA assumption assumption EPOC-2(with OTP) Secure (NM-CCA) Factoring Truly random OAEP Secure (NM-CCA) RSA Truly random Cramer-Shoup Secure (NM-CCA) DDH UOWHF 1.2 Security of TSH-ESIGN TSH-ESIGN [7] is proven to be secure in the strongest sense (existentially unforgeable against adaptive chosen message attacks: EUF-CMA) under the random oracle model and the approximate e-th root (AERP) assumption (with modulus n = p2q), which is the approximate version of the RSA assumption. That is, TSH-ESIGN is as secure as AERP (in the strongest sense in the random oracle model).
منابع مشابه
How to Repair ESIGN
The ESIGN signature scheme was provided with an inadequate proof of security. We propose two techniques to repair the scheme, which we name ESIGN-D and ESIGN-R. Another improvement of ESIGN is encouraged, where the public key is hashed together with the message. This allows to have a security proof in the multi key setting. Additionally, the lower security of ESIGN compared to RSA-PSS leads to ...
متن کاملAlmost Uniform Density of Power Residues and the Provable Security of ESIGN
ESIGN is an efficient signature scheme that has been proposed in the early nineties (see [14]). Recently, an effort was made to lay ESIGN on firm foundations, using the methodology of provable security. A security proof [15] in the random oracle model, along the lines of [2], appeared in support for ESIGN. However, several unexpected difficulties were found. Firstly, it was observed in [20], th...
متن کاملA Survey of ESIGN: State of the Art and Proof of Security
RSA, ESIGN, cryptography, digital signature, encryption, decryption, factoring RSA [1] generates digital signatures and cipher text, S, by performing exponentiation on a message, M, to the e-th power of the form M mod(n), where n is based on large prime numbers. RSA has been proven to be fundamentally secure, given the complexity of the e-th root mod(n) problem that RSA presents. Unfortunately,...
متن کاملQ in Esign
ESIGN signature scheme uses a particular modulus with a square factor. Each factor has the same number of bits. The goal of this study is to evaluate the security of this kind of modulus. Its security against known algorithms and other attacks which exploit its characteristics or not is studied.
متن کاملThe Insecurity of Esign in Practical Implementations
Provable security usually makes the assumption that a source of perfectly random and secret data is available. However, in practical applications, and especially when smart cards are used, random generators are often far from being perfect or may be monitored using probing or electromagnetic analysis. The consequence is the need of a careful evaluation of actual security when idealized random g...
متن کامل