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Streebog
Streebog () is a cryptographic hash function defined in the Russian national standard GOST R 34.11-2012 ''Information Technology – Cryptographic Information Security – Hash Function''. It was created to replace an obsolete GOST hash function defined in the old standard GOST R 34.11-94, and as an asymmetric reply to SHA-3 competition by the US National Institute of Standards and Technology. The function is also described in RFC 6986 and one out of hash functions in ISO/IEC 10118-3:2018. Description Streebog operates on 512-bit blocks of the input, using the Merkle–Damgård construction to handle inputs of arbitrary size. The high-level structure of the new hash function resembles the one from GOST R 34.11-94, however, the compression function was changed significantly. The compression function operates in Miyaguchi–Preneel mode and employs a 12-round AES-like cipher with a 512-bit block and 512-bit key. (It uses an 8×8 matrix of bytes rather than AES's 4×4 matrix.) S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
GOST (hash Function)
The GOST hash function, defined in the standards GOST R 34.11-94 and GOST 34.311-95 is a 256-bit cryptographic hash function. It was initially defined in the Russian national standard GOST R 34.11-94 ''Information Technology – Cryptographic Information Security – Hash Function''. The equivalent standard used by other member-states of the Commonwealth of Independent States, CIS is GOST 34.311-95. This function must not be confused with a different Streebog hash function, which is defined in the new revision of the standard GOST R 34.11-2012. The GOST hash function is based on the GOST (block cipher), GOST block cipher. Algorithm GOST processes a variable-length message into a fixed-length output of 256 bits. The input message is broken up into chunks of 256-bit blocks (eight 32-bit endianness, little endian integers); the message is padding (cryptography), padded by appending as many zeros to it as are required to bring the length of the message up to 256 bits. The remaining ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hash Function Security Summary
This article summarizes publicly known attacks against cryptographic hash functions. Note that not all entries may be up to date. For a summary of other hash function parameters, see comparison of cryptographic hash functions. Table color key Common hash functions Collision resistance Chosen prefix collision attack Preimage resistance Length extension *Vulnerable: MD5, SHA1, SHA256, SHA512 *Not vulnerable: SHA384, SHA-3, BLAKE2 Less-common hash functions Collision resistance Preimage resistance Attacks on hashed passwords Hashes described here are designed for fast computation and have roughly similar speeds. Because most users typically choose short passwords formed in predictable ways, passwords can often be recovered from their hashed value if a fast hash is used. Searches on the order of 100 billion tests per second are possible with high-end graphics processors. Special hashes called key derivation functions have been created to slow brute for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Second Preimage Attack
In cryptography, a preimage attack on cryptographic hash functions tries to find a message that has a specific hash value. A cryptographic hash function should resist attacks on its preimage (set of possible inputs). In the context of attack, there are two types of preimage resistance: * ''preimage resistance'': for essentially all pre-specified outputs, it is computationally infeasible to find any input that hashes to that output; i.e., given , it is difficult to find an such that . * ''second-preimage resistance'': for a specified input, it is computationally infeasible to find another input which produces the same output; i.e., given , it is difficult to find a second input such that . These can be compared with a collision resistance, in which it is computationally infeasible to find any two distinct inputs , that hash to the same output; i.e., such that . Collision resistance implies second-preimage resistance. Second-preimage resistance implies preimage resistance only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |