ARIA (cipher)

This article is about the block cipher. For other uses, see ARIA (disambiguation).

ARIA

General
First published	2003
Derived from	AES
Certification	South Korean standard
Cipher detail
Key sizes	128, 192, or 256 bits
Block sizes	128 bits
Structure	Substitution-permutation network
Rounds	12, 14, or 16
Best public cryptanalysis
Meet-in-the-middle attack on 8 rounds with data complexity 256

In cryptography, ARIA is a block cipher designed in 2003 by a large group of South Korean researchers. In 2004, the Korean Agency for Technology and Standards selected it as a standard cryptographic technique.

The algorithm uses a substitution-permutation network structure based on AES. The interface is the same as AES: 128-bit block size with key size of 128, 192, or 256 bits. The number of rounds is 12, 14, or 16, depending on the key size. ARIA uses two 8×8-bit S-boxes and their inverses in alternate rounds; one of these is the Rijndael S-box.

The key schedule processes the key using a 3-round 256-bit Feistel cipher, with the binary expansion of 1/π as a source of "nothing up my sleeve numbers".

Standardization

• KATS
  • KS X 1213:2004
• IETF
  • Algorithm
    • RFC 5794: A Description of the ARIA Encryption Algorithm
  • TLS/SSL
    • RFC 6209: Addition of the ARIA Cipher Suites to Transport Layer Security (TLS)

External links

• ARIA home
• Lazarus/Delphi port of ARIA