AI_FeedbackCipher

 

 

 

 

Table 2-1Algorithm methods for block ciphers

 

 

 

 

 

 

 

 

 

Algorithm methods to

 

 

 

encryptionMethodName

include in chooser

Parameters

Key Size

 

 

 

 

 

Decryption

 

 

 

 

“des”

AM_DES_DECRYPT;

null

8 bytes

“des_ede”

AM_DES_EDE_DECRYPT;

null

24 bytes

“desx”

AM_DESX_DECRYPT;

null

24 bytes

“rc2”

AM_RC2_DECRYPT;

Pointer to an

1 - 128 bytes

 

 

A_RC2_PARAMS structure

 

 

“rc5”

AM_RC5_DECRYPT;

Pointer to an

0 - 255 bytes;

 

 

A_RC5_PARAMS structure

32-bit word

“rc5_64”

AM_RC5_64DECRYPT;

Pointer to an

0 - 255 bytes;

 

 

A_RC5_PARAMS structure

64-bit word

"rc6"

AM_RC6_DECRYPT;

Pointer to an

 

 

 

 

A_RC6_PARAMS structure

 

 

 

 

The RC2 algorithm methods, AM_RC2_ENCRYPT and AM_RC2_DECRYPT, require an

A_RC2_PARAMS structure:

 

 

 

 

 

 

 

 

 

typedef struct {

 

 

 

 

unsigned int effectiveKeyBits;

/* effective key size in bits */

 

} A_RC2_PARAMS;

 

 

 

 

 

 

 

 

 

The RC5 algorithm methods, AM_RC5_ENCRYPT, AM_RC564_ENCRYPT, AM_RC5_DECRYPT, and AM_RC564_DECRYPT, require an A_RC5_PARAMS structure. Note that the 64-bit versions of the RC5 algorithm, AM_RC5_64_ENCRYPT and AM_RC5_64_DECRYPT, are evaluation implementations and are not optimized in Crypto-C 4.3:

typedef struct

{

 

 

 

unsigned int

version; / * currently version 1.0

-- defined as 0x10

*/

unsigned int

rounds;

/* number of rounds (0 - 255) */

unsigned int

wordSizeInBits;

/* 32 for “rc5”

or 64 for “rc5_64”

*/

}A_RC5_PARAMS;

The RC6 algorithm methods, AM_RC6_ENCRYPT and AM_RC6_DECRYPT, require an

C h a p t e r 2 A l g o r i t h m I n f o Ty p e s

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RSA Security 5 manual AIFeedbackCipher