In cryptography, CMAC (Cipher-based Message Authentication Code) is a block cipher-based message authentication code algorithm. It may be used to provide assurance of the authenticity and, hence, the integrity of binary data. This mode of operation fixes security deficiencies of CBC-MAC (CBC-MAC is secure only for fixed-length messages).
The core of the CMAC algorithm is a variation of CBC-MAC that Black and Rogaway proposed and analyzed under the name XCBC and submitted to NIST. The XCBC algorithm efficiently addresses the security deficiencies of CBC-MAC, but requires three keys. Iwata and Kurosawa proposed an improvement of XCBC and named the resulting algorithm One-Key CBC-MAC (OMAC) in their papers. They later submitted OMAC1, a refinement of OMAC, and additional security analysis. The OMAC algorithm reduces the amount of key material required for XCBC. CMAC is equivalent to OMAC1.
To generate an ℓ-bit CMAC tag (t) of a message (m) using a b-bit block cipher (E) and a secret key (k), one first generates two b-bit sub-keys (k1 and k2) using the following algorithm (this is equivalent to multiplication by x and x2 in a finite field GF(2b)). Let ≪ denote the standard left-shift operator and ⊕ denote exclusive or:
The Constellation Brands-Marvin Sands Performing Arts Center (CMAC), originally the Finger Lakes Performing Arts Center (FLPAC) is an outdoor concert venue in the Town of Hopewell, New York, just east of the City of Canandaigua, on the grounds of Finger Lakes Community College.
The amphitheater opened in 1983, with a mix of seating under the open air roof and on the hillside lawn looking down into the facility. It is the summer home of the Rochester Philharmonic Orchestra and is managed by SMG (the same firm that manages the Blue Cross Arena in Rochester, New York).
Between the 2005 and 2006 seasons the amphitheater was rebuilt at a cost of about $13 million, to add 54 elevated luxury booths (seating capacity of 4 per booth), expand the general seating under the amphitheater roof from 2,600 to 5,000, and install new state of the art house lighting and sound systems.
The center is named after Constellation Brands, a wine company, and Marvin Sands, founder of the Canandaigua Brands winery.
CMAC usually refers to "Cipher-based Message Authentication Code", a cryptographic algorithm.
CMAC may also refer to: