RIPEMD320 hash

 

About RIPEMD320 hash

RIPEMD-320 (RACE Integrity Primitives Evaluation Message Digest) is a cryptographic hash function that extends the RIPEMD family to provide a longer 320-bit hash output. It was developed as an enhancement over RIPEMD-128, RIPEMD-160, and RIPEMD-256 to offer increased security and resistance against collision attacks.

Characteristics of RIPEMD-320

  1. Fixed-Length Output:

    • RIPEMD-320 produces a fixed-length output of 320 bits (40 bytes), regardless of the input data's length.

  2. Input Padding:

    • Similar to other members of the RIPEMD family, RIPEMD-320 pads the input message so that its length is congruent to 448 modulo 512 bits. Padding involves appending a single '1' bit followed by '0' bits until the message length is 64 bits short of a multiple of 512. The length of the original message (before padding) is then appended as a 64-bit integer.

  3. Processing in Blocks:

    • RIPEMD-320 processes the input message in 512-bit (64-byte) blocks.

  4. Initialization Vector (IV):

    • RIPEMD-320 uses an initial vector (IV) consisting of ten 32-bit words:
      • IV0 = 0x67452301
      • IV1 = 0xEFCDAB89
      • IV2 = 0x98BADCFE
      • IV3 = 0x10325476
      • IV4 = 0xC3D2E1F0
      • IV5 = 0x76543210
      • IV6 = 0xFEDCBA98
      • IV7 = 0x89ABCDEF
      • IV8 = 0x01234567
      • IV9 = 0x3C2D1E0F

  5. Compression Function:

    • The compression function of RIPEMD-320 involves multiple rounds of operations, including bitwise logical functions (AND, OR, XOR, NOT), additions modulo 2^32, rotations, and bitwise shifts.

Algorithm Steps

  1. Initialization:

    • Initialize the state variables (A, B, C, D, E, F, G, H, I, J) to the IV values.

  2. Padding:

    • Pad the input message according to the specified padding rules.

  3. Processing:

    • Divide the padded message into 512-bit blocks.
    • For each block, perform the rounds of the compression function, updating the state variables.

  4. Output:

    • After processing all blocks, concatenate the state variables (A, B, C, D, E, F, G, H, I, J) to produce the final 320-bit hash value.

Security and Usage

  • Security:

    • RIPEMD-320 is designed to provide strong security against collision attacks and preimage attacks. Its 320-bit output size provides a higher level of security compared to shorter variants like RIPEMD-128, RIPEMD-160, and RIPEMD-256.

  • Usage:

    • RIPEMD-320 has been used in various cryptographic applications where a longer hash output and increased security assurances are required. However, its adoption has been limited compared to more widely accepted hash functions like SHA-2 and SHA-3, which offer similar or higher security guarantees and are more standardized in modern cryptographic protocols.

Summary

RIPEMD-320 is a cryptographic hash function that produces a 320-bit hash value, designed to provide strong security properties against collision attacks and preimage attacks. It extends the RIPEMD family to offer a longer hash output compared to its predecessors, making it suitable for applications requiring higher security assurances. However, its usage has been less prevalent in modern cryptographic applications compared to other established hash functions.