java.lang.Object | |
↳ | org.bouncycastle.crypto.macs.CMac |
CMAC - as specified at www.nuee.nagoya-u.ac.jp/labs/tiwata/omac/omac.html
CMAC is analogous to OMAC1 - see also en.wikipedia.org/wiki/CMAC
CMAC is a NIST recomendation - see csrc.nist.gov/CryptoToolkit/modes/800-38_Series_Publications/SP800-38B.pdf
CMAC/OMAC1 is a blockcipher-based message authentication code designed and analyzed by Tetsu Iwata and Kaoru Kurosawa.
CMAC/OMAC1 is a simple variant of the CBC MAC (Cipher Block Chaining Message Authentication Code). OMAC stands for One-Key CBC MAC.
It supports 128- or 64-bits block ciphers, with any key size, and returns a MAC with dimension less or equal to the block size of the underlying cipher.
Public Constructors | |||||||||||
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create a standard MAC based on a CBC block cipher (64 or 128 bit block).
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create a standard MAC based on a block cipher with the size of the
MAC been given in bits.
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Public Methods | |||||||||||
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Compute the final stage of the MAC writing the output to the out
parameter.
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Return the name of the algorithm the MAC implements.
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Return the block size for this MAC (in bytes).
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Initialise the MAC.
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Reset the mac generator.
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add a single byte to the mac for processing.
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Inherited Methods | |||||||||||
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From class
java.lang.Object
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From interface
org.bouncycastle.crypto.Mac
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create a standard MAC based on a CBC block cipher (64 or 128 bit block). This will produce an authentication code the length of the block size of the cipher.
cipher | the cipher to be used as the basis of the MAC generation. |
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create a standard MAC based on a block cipher with the size of the MAC been given in bits.
Note: the size of the MAC must be at least 24 bits (FIPS Publication 81), or 16 bits if being used as a data authenticator (FIPS Publication 113), and in general should be less than the size of the block cipher as it reduces the chance of an exhaustive attack (see Handbook of Applied Cryptography).cipher | the cipher to be used as the basis of the MAC generation. |
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macSizeInBits | the size of the MAC in bits, must be a multiple of 8 and <= 128. |
Compute the final stage of the MAC writing the output to the out parameter.
doFinal leaves the MAC in the same state it was after the last init.
out | the array the MAC is to be output to. |
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outOff | the offset into the out buffer the output is to start at. |
Return the name of the algorithm the MAC implements.
Return the block size for this MAC (in bytes).
Initialise the MAC.
params | the key and other data required by the MAC. |
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Reset the mac generator.
add a single byte to the mac for processing.
in | the byte to be processed. |
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